JPH086457A - Cartridge and image forming apparatus - Google Patents

Abstract

(57) [Summary] [Objective] A photosensitive body and a driven portion of a developing means are separated into cartridges, and a compact and inexpensive printer or facsimile can be realized by avoiding concentration of driving force. A removable cartridge comprises a photosensitive drum having a driven member for rotation and a developing roller 12 having an F # gear which is rotatably supported and rotatably driven about a fulcrum.
And an E # gear which is supported by the lower cartridge case 18 and is driven to rotate from the main body, and an urging means for urging the developing roller 12 toward the photosensitive drum.
The structure is such that the # gear is rotationally driven via the universal coupling 110, and the main body is provided with rotary drive means for rotationally driving the photosensitive drum and the E # gear, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an image forming apparatus for forming an image on a sheet material such as a printer or a facsimile, and more particularly to a detachable cartridge structure and a structure of an apparatus equipped with this cartridge. .

[0002]

2. Description of the Related Art As a typical example of a conventional image forming apparatus or cartridge, a structure as shown in Japanese Patent Publication No. 63-67185 and USP 4835565 is generally known. On the other hand, in USP 4835565,
A plurality of adjoining rotating bodies are arranged in a developing unit which is movable toward and away from the photosensitive body and is pressed and biased against the photosensitive body. The rotating body, which is supported by the developing unit case and is movable toward and away from the main body, is an Oldham coupling or the like that is provided at the end of the gear shaft that is driven by an idle gear that is driven from the main body. The drive structure is driven by the coupling means of FIG. 1 and is effective for rotationally driving a rotating body that can be moved in and out of contact, but when the idle gear provided in the developing unit case is driven from the main body side, the structure is arranged as described above. In the developing unit, the pressing force is changed by the action of the axial force generated by the pressure angle of the gear driven from the main body side, and the contact state with the photoconductor may become unstable.

In the main diagram of Japanese Examined Patent Publication No. 63-67185, the photosensitive member which is rotationally driven from the main body of the apparatus drives the developing means, and the driving force of the photosensitive member is uniform. The drive unit of the apparatus main body and the driven unit on the cartridge side are concentrated and are large in size and expensive because of the necessity of having high rigidity.

[0004]

As described above, according to the conventional technique, the pressing force is changed by the action of the axial force generated by the pressure angle of the gear driven from the main body side, and the contact state with the photosensitive member is changed. Not only becomes unstable and the apparatus becomes large, but also it is an expensive image forming apparatus.

By the way, the environment surrounding computers these days is accelerating downsizing due to the rise of small notebook type computers, and the market for personal use is expanding, so that personal computers can be placed on the table with a margin. As described above, there has been an increasing demand for miniaturization of external terminals such as printers and facsimiles corresponding to the miniaturization of computers and appearance of inexpensive products.

Therefore, the present invention is to solve the above problems, and an object of the present invention is to provide a driven portion of a cartridge driven from the main body of the image forming apparatus, a driven portion of a photosensitive member and a developing means. The driven parts of the cartridge are separated to avoid concentration of the driving force, and the driven parts on the cartridge side or the driving parts on the main body side are simplified, and The present invention is to meet the demands in the personal use market by developing a small and inexpensive image forming apparatus by constructing a stable driving relationship with little jitter.

[0007]

A cartridge detachable from an image forming apparatus main body according to the present invention is formed by exposing a photosensitive member having a driven member to be rotated and driven by the image forming apparatus. The latent image thus developed is developed with toner to visualize the latent image, and the developing device has a second rotationally driven device that is rotationally driven, a supporting device that supports the developing device, and a first rotational device that is rotationally driven from the image forming apparatus. It has a rotation driving means, a housing for supporting the photoconductor, the developing means, and the first rotation driven means, and a biasing means for biasing the developing means toward the photoconductor, and the supporting means is a fulcrum. Is rotatably supported about the second rotationally driven means, and the second rotationally driven means is configured to be rotationally driven from the first rotationally driven means via a universal coupling.

Further, the image forming apparatus of the present invention includes a photosensitive member having a rotationally driven unit which is rotationally driven by the image forming apparatus, and a latent image formed by exposing the photosensitive member to light to develop the toner to develop a visible image. And supports the developing means having the second rotationally driven means rotationally driven, the first rotationally driven means rotationally driven from the image forming apparatus, the photoconductor, the developing means and the first rotationally driven means. The support unit has a housing and a biasing unit that biases the developing unit toward the photosensitive member. The support unit is rotatably supported about a fulcrum, and the second rotation driven unit is the first driven unit. It is characterized in that it is provided with a rotation driving means which is rotationally driven from the rotation driving means through the universal coupling and rotationally drives the photoconductor and the second driven means.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to FIGS.

1 to 10 show a suitable embodiment of the (cartridge and) image forming apparatus of the present invention, FIGS. 11, 12 and 13 show other embodiments, and FIG. 1 shows the embodiment of the present invention. 2 is a cross-sectional view of a left side main part showing the entire image forming apparatus.
FIG. 3 is a sectional view of a front main part showing a cross section of the front main part.

FIG. 3 is a sectional view of a left side main part showing a left side main part of the cartridge of the present invention. 4 and 5 are cross-sectional views of the right side principal part of the image forming apparatus of the present invention, FIG. 4 is a first right side principal part sectional view, and FIG. 5 is a second right side principal part sectional view. The figures show cross-sections in different positions.

FIG. 6 is a developed cross-sectional view showing a part of the developed cross-section of the rotary drive transmission portion of the image forming apparatus of the present invention.

FIG. 7 is a sectional view of the principal part of the right side surface of the cartridge of the image forming apparatus according to the present invention, showing the rotational driven relationship.

FIG. 8 is a cross-sectional view of the main part of the upper surface of the cartridge of the image forming apparatus of the present invention.

FIG. 9 is a sectional view of the main part of the upper surface of the cartridge showing the rotational drive relationship of the cartridge of the image forming apparatus of the present invention.

10 to 13 are views for explaining the rotational drive relationship of the cartridge of the present invention. FIG. 10 is an explanatory view of the first rotary drive system, FIG. 11 is an explanatory view of the second rotary drive system, and FIG. 3 rotation drive system explanatory drawing, FIG. 13 is a 4th rotation drive system explanatory drawing.

First, the image forming section of this embodiment will be described with reference to FIG. 1 and other figures.

The main part of the image forming means of this embodiment is shown in FIG.
The photosensitive drum 1, the charging roller 2, the cleaner portion 90, the developing portion 10, which are arranged in the substantially central portion as shown in the sectional view of the left side of FIG.
It is configured by the toner transport units 30 and 30a.

The image forming process will be described in order with reference to FIGS. 1 and 3. The charging roller 2 in this embodiment is formed of a semiconductive elastic body such as rubber, and is a photosensitive member that rotates in the direction of the arrow in the figure. DC (-) 2k while following drum 1
When a bias of about v or less is applied, the photosensitive drum 1 can be charged to a charging potential of (−) 600V to (−) 700V.

The charging roller 2 is pressed and supported toward the photosensitive drum 1 by a pressing mechanism composed of a spring 3 and the like, and is pressed against the photosensitive drum 1 at a total pressure of about 1 kg.

Next, the photosensitive drum 1 is image-exposed to form a latent image by the light beam emitted from the exposing device 40 which will be described later in detail and entering from the optical path 49, and the potential of the image exposing portion is (-). ) 10V to (-) 150V.

Next, in the developing section 10, the supply roller 13 which is formed of a semiconductive elastic body such as foamed rubber and rotates in the direction of the arrow in the drawing is a toner which can be charged to the same polarity as the above-mentioned charging potential. The toner in the storage unit 11 for storing the toner is coated on the surface of the toner and rotated, and is rubbed against the developing roller 12 formed of a semiconductive elastic body such as a rubber material that rotates in the direction of the arrow in the figure to rub the toner. Is triboelectrically charged to the negative polarity, and the surface of the developing roller 12 is coated with toner.

The toner coated on the surface of the developing roller 12 is formed of an elastic body such as a stainless steel plate and is in contact with the outer periphery of the developing roller 12 at a total pressure of about 1 kg over substantially the entire axial direction. By rubbing the formed toner with a regulating blade 14 for regulating the coating layer having a predetermined thickness, the toner is approximately 10
The toner layer is regulated by a thin toner layer having a thickness of about μm, and is triboelectrically charged to a more uniform (−) polarity.

The developing roller 12 has a DC (-) 200
A bias of about V to (-) 400V is applied,
The thinned toner layer is conveyed to the photosensitive drum 1 and subjected to reversal development on the image exposure portion of the photosensitive drum 1 at and around the nip portion formed by the developing roller 12 and the photosensitive drum 1 being in pressure contact with each other.

By the way, the toner in the storage unit 11 is as shown in FIG.
As shown in detail in FIG.
Lower cartridge case 18, regulating blade 14, pressing member 16 of the regulating blade 14, and developing roller 12
The space surrounded by the supply roller 13 is stored in a narrow predetermined space partitioned by a seal 15 having elasticity and formed of, for example, a foam rubber material.

Next, the toner image reverse-developed on the image exposure portion of the photosensitive drum 1 is transferred by the transfer portion 80, which will be described in detail later. The transfer residual toner is a thin plate material such as mylar sheet material. The formed scooping sheet 91 slides through and is scraped off by the cleaning blade 92 that is in pressure contact with the photosensitive drum 1, and is stored in a predetermined space 93 formed by the scooping sheet 91 and the cleaning blade 92.

The cleaned photosensitive drum 1 can be transferred to the next image forming process again. After cleaning, if the potential remaining on the photosensitive drum 1 is removed by light irradiation or the like, the surface potential of the photosensitive drum 1 is removed. Can be brought closer to the initial state.

Here, the handling of toner will be described. In the conventional image forming apparatus, a predetermined amount of toner corresponding to the operating life of the main components such as the photoconductor is mounted as a cartridge enclosed in a casing of an integrated structure, which not only enlarges the entire apparatus but also replaces it. Although the image forming apparatus is expensive although the workability of maintenance is enhanced, the present embodiment has a configuration completely different from the conventional concept.

First, the amount of toner in the storage unit 11 is limited to the minimum necessary storage amount that does not hinder the image forming process, and the space space of the storage unit 11 is reduced. Then, the toner that decreases with the development is dropped and replenished from the toner transport unit 30a that transports the toner described later in the space of the storage unit 11.

On the other hand, the toner scraped off by the cleaning blade 92 is stored in a predetermined space 93 formed by the scooping sheet 91 and the cleaning blade 92, and the toner conveying portion 3 is increased as the storage amount increases.
Transition to 0.

Toners including endless coil springs 31 and 31a (which are endless and integrated, although they are described later in detail) are included in the toner conveying portions 30 and 30a. The toner transporting units 30 and 30a are provided with a mechanism for transporting toner by a transporting unit, and are disposed substantially horizontally and horizontally with the photosensitive drum 1 in the middle in the drawing. The toners of the toner conveying unit 30 and the toner conveying unit 30a which are connected to each other are circulated and conveyed.

Next, the toner circulation function will be described. With respect to the toner amount (developing toner amount) in the storage unit 11 consumed by the above-described development, the transfer residual toner amount scraped by the cleaning blade 92 and transferred to the toner conveying unit 30 (reproduced toner amount). In the present embodiment, the relationship is 10% to 30%. Even if the toner is circulated and conveyed as described above, the toner is consumed by the repeated development, and the toner is stored in the storage unit 11. Toner will decrease.

Therefore, in the present embodiment, in order to make up for the reduced toner, a toner replenishing means for dropping by its own weight is arranged in the conveying path for circulating the toner, which will be described in detail later, and the amount of the reduced toner is reduced. Toner is replenished and circulated and conveyed together with the above-mentioned recycled toner, and the toner is conveyed from the toner conveying section 30a to the storage section 1.
It is configured to be dropped and replenished to 1.

Next, referring to FIGS. 3, 8 and 9, regarding the stable structure of the nip portion constituted by the photosensitive drum 1 rotatably supported by the developing roller 12 and the cartridge lower case 18 in pressure contact with each other. explain.

The supply roller 13 formed of a semi-conductive elastic body such as foamed rubber and the developing roller 12 formed of a semi-conductive elastic body such as a rubber material are each made of metal as a core metal. Having a flexible rigid body portion and provided with supporting portions 12a and 13a extending at both ends of the elastic body, respectively, and these supporting portions 12a and 13a are rotatably supported by a supporting member 5 as shown in FIG. Has been done. Although the supply roller 13 and the developing roller 12 are shown supporting the right side in FIG. 9, the opposite side has the same supporting structure, and is rotatably supported by the supporting member 5A in FIG.

Incidentally, the supply roller 13 and the developing roller 12
3, the supply roller 13 and the developing roller 12 are supported at a fixed pitch that is narrower than the pitch at which the outer peripheries of the supply roller 13 and the developing roller 12 are in contact with each other. The positional relationship is shown in detail in the drawing.

Then, the supply roller 13 and the developing roller 12
Are rotationally driven in the directions of the arrows in the drawing to rub against each other, and if the above-mentioned support pitch is extremely narrowed, the rotational driving torque increases, and deterioration of the toner rubbed between both roller nips is caused. In view of absorption of variations in constituent members related to this support, in the present embodiment, the supply roller 13 and the developing roller 12 are supported at a fixed pitch that is 0.25 mm narrower than the pitch at which the outer circumferences of the supply roller 13 and the development roller 12 are in contact with each other.

The supporting member 5 and the supporting member 5A, which rotatably support both ends of the supply roller 13 and the developing roller 12, respectively,
The support member 5 is integrally connected through a connecting member 6 by a fixing means such as a screw, and the support member 5 is rotated by a support pin 5a which is inserted into a part of the cartridge lower case 18, as shown in FIG. It is movably supported, and FIG. 3 shows a state in which only one side is supported, but the other side has a similar support structure, and the support member 5 shown in FIG.
A is inserted through a part of the lower cartridge case 18 and is rotatably supported by a similar support pin 5Aa arranged at the same sectional position as the support pin 5a shown in FIG.

Then, the supply roller 13 and the developing roller 12
Both ends of which are rotatably supported and connected by the connecting member 6 together with the above-mentioned regulating blade 14 using the support pins 5a and 5Aa as supporting shafts so that the above-mentioned image forming process is not hindered. The toner can be integrally rotated with respect to the photosensitive drum 1 in the space of the toner storage unit 11 configured so that the storage amount is limited.

When the support pin 5a and the support pin 5Aa are arranged at the above-described positions, the cartridge lower case 18, the support member 5, and the support member 5A are arranged so that they can be easily rotated on the basis of the integral structure. The relationship is such that a gap is formed so as to be free in the rotational direction, and this gap is blocked by a sealing member having elasticity (not shown) to prevent toner leakage.

On the other hand, in order to form a stable nip portion by pressing the developing roller 12 and the photosensitive drum 1 in the above state, the developing roller 12 is rotated about the supporting pin 5a and the supporting pin 5Aa as a supporting shaft so that the developing roller 12 is exposed to light. Springs 8 and 8A for urging toward the drum 1 are provided between the lower cartridge case 18 and the supporting member 5 and the supporting member 5A.

By the way, with respect to the support structure of the support member 5 and the support member 5A by the support pin 5a and the support pin 5Aa, in this embodiment, as a means for preventing the rotation failure even if the left and right support positions are misaligned. In one of the support portions, the insertion portion through which the cartridge lower case 18 and the support pin 5a of the support member 5 are inserted is formed so as to be rotatable while supporting the support pin 5a in a desired relationship. The case 18 and the insertion portion through which the support pin 5Aa of the support member 5A is inserted are not illustrated in detail, but the support pin 5Aa is not shown.
Is provided with a desired clearance so that it can be moved toward and away from the photosensitive drum 1 to prevent the rotation defect of the above-mentioned configuration from occurring.

Although the desired clearance is provided in the support portion of the support pin 5a in this embodiment, the desired clearance may be provided in the support pin 5Aa, or the support pin 5a and the support pin 5 may be provided.
Even if it is provided on both sides of Aa, the occurrence of the rotation defect of the above configuration is prevented.

Here, the toner replenishing means and the toner conveying means for circulating and conveying the toner will be described with reference to FIGS. 2, 7 and 8.

As shown in FIG. 3, the endless coil springs 31 and 31a that circulate and convey the toner are enclosed by the upper cartridge case 17 and the lower cartridge case 18, and the toner tank 20 can be freely attached / detached (attachment / detachment mechanism). Is omitted from the detailed description in the drawing), and a predetermined amount of toner is enclosed therein, and the toner is replenished by being mounted in a toner-enclosed state, and when this toner is consumed, it is replaced with a new toner tank 20. It is configured.

The endless coil springs 31 and 31a that circulate and convey the toner are formed endlessly and integrally, although the reference numerals are different for convenience of explanation in the drawing.

The main part of the toner tank 20 is a cylindrical tank case 21 having a bottom portion in the lower part of the figure, a cover 22 fixed to the upper portion to seal the toner, and the tank case 21 and the cover 22. A plurality of blades 23 that are sealed together with the toner to stir the rotatable toner
and an agitator 23 having b, and an endless coil spring 31, which circulates and conveys toner,
A detachable operation is possible with respect to the state in which 31a is enclosed by the cartridge upper case 17 and the cartridge lower case 18 (the detachment mechanism is omitted in the detailed description of the drawing).

On the other hand, in order to drive the endless coil springs 31 and 31a which circulate and convey the toner in the direction of the arrow in FIG. 8, an endless coil enclosed by a cartridge upper case 17 and a cartridge lower case 18 so as to be circulatively movable. The drive means 25 for the coil springs 31 and 31a is arranged in a part of the arrangement path of the springs 31 and 31a, and the protruding portion 25a having a wedge-shaped protruding end is formed in a part of the drive means 25 so that the rotatable convex portion 25a is provided.
When the toner tank 20 is attached to the predetermined position, the rotatable convex portion 25a formed in a wedge shape and the concave portion 23c formed at one end of the one agitator 23 are engaged with each other to be rotationally driven. It

As the driving means 25 for the endless coil springs 31 and 31a that circulates and conveys the toner, any rotating body that can engage with the coil springs 31 and 31a can be driven, but in the present embodiment, the coil springs are used. A helical gear having a twist angle close to the lead angle of the stretched state of 31, 31a is employed to stabilize the engagement relationship with the coil springs 31, 31a.

The toner agitated by the rotation of the agitator 23 is circulated and conveyed through the opening 21a formed at the bottom of the tank case 21 and the opening 17a of the cartridge upper case 17 provided opposite to the opening 21a. Endless coil springs 31 and 31a
Is configured to drop by itself in the toner circulating and conveying path, and the opening 2 is interlocked with the attachment / detachment of the toner tank 20.
The opening 1a and the opening 17a are opened and closed. (Not shown) The toner dropped by its own weight in the toner circulating and conveying path in which the coil springs 31 and 31a are arranged is circulated and conveyed in the direction of the arrow in FIG. Although the toner drops from the upper portion of 13 by its own weight and is stored in the toner storage unit 11 described above with reference to FIG. 3, the toner storage unit 11 is extremely narrow as described above, and therefore the toner storage unit 11 can store different toner depending on the image form. Due to the relationship between the consumption amount and the supply amount, the toner storage unit 11 may become full. In this state, the toner is circulated and conveyed by the coil springs 31 and 31a without falling by its own weight.
The toner drop from the toner tank 20 described above is also suspended.

The above is the main part of the image forming means of the present embodiment, in which the photosensitive drum 1, the charging roller 2, the cleaner part 90, the developing part 10, and the toner conveying parts 30, 30a are arranged in the above-mentioned relationship. A cartridge lower case 18 mainly responsible for the main part and a cartridge upper case 17 also responsible for the cover thereof are detachable from the main body as a cartridge having these as a unit structure, and are integrated during maintenance of the above structure part. It is configured to be removed and repaired or replaced.

With respect to the relationship between the cartridge and the main body, predetermined positioning is performed by a positioning means (not shown), and the cartridge is fixed by a fixing means (not shown).

Next, the transfer section 80 for transferring the reversal-developed toner image to the image exposure section of the photosensitive drum 1 will be described with reference to FIG.

The main portion of the transfer portion 80 of this embodiment is pressed toward the photosensitive drum 1 from below by a pressing mechanism 82 with a total pressure of several 100 g, and the latent image in the image exposure portion of the photosensitive drum 1 is reversely developed. DC1K with the opposite polarity to the toner image
A rotatable transfer roller 81 which is provided with a bias voltage of about V and is formed of a conductive or semi-conductive elastic body such as rubber, and a main part of the sheet material conveying unit 70 described in detail later. It is composed of a sheet material conveying base 71 that supports the transfer roller 81 together with the constituent members, and the sheet material conveying base 71 engages the positioned portion with the positioning portion formed on the main chassis 100 that serves as a reference for the internal configuration of the apparatus ( It is positioned at a predetermined position (not shown), and is fixed to the main chassis 100 by a fixing means such as a screw.

Then, the toner image conveyed to the nip portion formed by the pressing action of the photosensitive drum 1 and the transfer roller 81 forms the sheet material fed from the sheet material conveying portion 70, which will be described later, in the nip portion. It is merged and transferred.

Next, the fixing unit 60 for feeding the sheet material onto which the toner image on the photosensitive drum 1 has been transferred and fixing it will be described.

The main part of the fixing unit 60 of the present embodiment is arranged on the downstream side in the sheet material conveying direction and has a heating element such as a halogen heater as a heat generating means built in the hollow portion of the aluminum pipe material and is rotatable. 63 and a toner image transferred onto the sheet material as a pressing means for pressing the sheet material toward the fixing roller 63 by a pressing mechanism such as a spring 66 with a total pressure of several Kg. A pressure roller 67, which has a semi-conductive elastic body formed on at least the surface thereof and is rotatable at the same peripheral speed as the fixing roller 63, is provided, and a pair of discharge rollers for discharging the conveyed sheet material to the outside of the apparatus. 61 and a fixing base 64 that supports the above-mentioned structural members and takes charge of the fixing unit 60 as a unit structure. The fixing base 64 serves as a main system that serves as a standard for the internal structure of the apparatus. Is fixed to the main chassis 100 by chromatography by engagement of the positioning portion (not shown) for positioning portion formed in the sheet 100 is positioned at a predetermined position, for example, screws or the like fixing means.

The toner image transferred from the transfer portion 80 to the sheet material and conveyed to the nip portion formed by the pressing action of the fixing roller 63 and the pressure roller 67 is formed on the sheet material at a predetermined temperature at this nip portion. It is fixed.

Next, the paper feed unit 70 for feeding a sheet material such as paper toward the transfer unit 80 will be described.

A sheet feeding tray 72, which accommodates a large number of sheet materials P such as paper and is arranged at the rear of the apparatus, feeds the sheet material P at the lower end thereof with a high friction resistance material such as rubber. Part 7
A well-known pressing mechanism 74 that selectively presses the rotatable sheet feeding roller 73 of 0 is provided.

The sheet feeding section 70 on the main body side of the apparatus is arranged so as to face the sheet feeding roller 73 with the sheet material P interposed therebetween, and only the uppermost one sheet material from the many sheet materials P is fed by the sheet feeding roller 73. A sheet material feeding control mechanism 75 for preventing the feeding of the sheet material such that the sheet material is separated by the rotation of 73 and the second and subsequent sheet materials are not fed, and the sheet feeding section 70 to the transfer section. A sheet material detecting means 77 including a photosensor or the like arranged in a sheet material conveying path for feeding a sheet material such as paper toward 80, and a main part of the sheet material conveying section 70. The sheet material conveying base 71 that supports the transfer roller 81 described above together with the constituent mechanism is provided. Further, although not shown, a mechanism for releasing the pressing of the transfer roller 81 against the photosensitive drum 1 is also provided, and the sheet feeding unit 70 and Transfer unit 80 The sheet material transport base 71 is carried by the unit configuration, and as described above, the sheet material transport base 71 engages the positioned portion with the positioning portion formed on the main chassis 100 that serves as a reference for the internal configuration of the apparatus (illustrated). It is positioned at a predetermined position by (omission) and is fixed to the main chassis 100 by fixing means such as a screw.

When the paper feed roller 73 is driven to rotate in the above-described structure, one sheet of material follows the sheet material conveying path and is fed to the transfer section 80.

Here, the feeding control of the sheet material will be described. The sheet feeding roller 73 is rotationally driven by a desired command to feed one sheet of material into the sheet material conveying path, and the sheet feeding roller 73 is responsive to the detection signal of the sheet material detecting unit 77.
The sheet material is sandwiched and stopped to stand by for the above-mentioned transfer.

The stop timing of the paper feed roller 73 may be stopped by a detection signal of the sheet material detecting means 77, but a delay means such as a timer from this detection signal stops and waits for a predetermined time. May be.

That is, the toner image reverse-developed on the image exposing portion of the photosensitive drum 1 at the nip portion formed by the developing roller 12 and the photosensitive drum 1 which are in pressure contact with each other is transferred to the photosensitive drum 1 by the rotation of the photosensitive drum 1. The time for the roller 81 to reach the transfer portion 80 that forms the nip portion formed by pressure contact,
It suffices if the time for which the sheet material is fed from the standby state and the sheet material reaches the transfer portion 80 can be controlled in a desired relationship,
In this embodiment, the latter is adopted.

By the way, in the present embodiment, the sheet material detecting means 77 including a photo sensor for detecting the presence or absence of the sheet material is arranged in the sheet material conveying path of the sheet feeding section 70, and the fixing section 60 of the fixing section 60 is provided on the other side. Fixing roller 63 and pressure roller 6
A second sheet material detecting means 65 similar to the downstream side in the sheet material conveying direction from the nip portion formed by the pressing action of 7 is provided to detect the sheet material conveying state and to detect the sheet material detecting means 77 and the second sheet material detecting means 77. The detection signal from the sheet material detecting means 65 is processed in a predetermined relationship to monitor the jam condition in the apparatus.

As described above, in the image forming apparatus of this embodiment,
The sheet material conveying path through which the sheet material P is ejected from the sheet feeding section 70, the transfer section 80, and the fixing section 60 including the sheet ejection roller pair 61 is arranged in the lower part of the cartridge at approximately the center of the entire apparatus. Is.

Next, the exposure device 40 for exposing the photosensitive drum 1 to a latent image will be described. The main part of the exposure device 40 is a motor 41 that rotates at 10,000 rpm, a control circuit board (not shown) that controls the rotation of the motor 41, and the motor 41.
A deflection scanning means 43 which is mounted on the output shaft of the optical disc 1 and rotates to deflect and scan a light beam emitted from a light emitting element such as a semiconductor laser (not shown); and an optical path 49 for irradiating the light beam toward the photosensitive drum 1. A reflection mirror 44 and the like to be formed,
The exposure unit case 42 is configured by accommodating the above-mentioned main components into a unit, and the exposure unit case 42 engages the positioned portion with the positioning portion formed on the main chassis 100 that serves as a reference for the internal configuration of the apparatus. It is positioned at a predetermined position by (not shown) and is fixed to the main chassis 100 by fixing means such as a screw.

Regarding the deflection scanning means 43, Japanese Patent Application No. 5-121995 filed previously by the present applicant.
As described in detail in the above, the optical scanning is small and inexpensive. In this embodiment, the optical path length from the deflection scanning means 43 to the photosensitive drum 1 is set to about 160 mm, but about 140 mm. It is also possible to correspond to the short optical path length.

Next, the control section 50 which controls the above-mentioned respective mechanical sections will be described with reference to FIGS. 1, 2 and 8. The main part of the controller 50 is a first control circuit board 51 which is arranged at the lowermost end of the device and has at least a power supply circuit section and an operation control circuit section of each mechanism section, and the first control circuit board 51. In contrast to the second control circuit board 52, which is arranged substantially vertically to the left end of the device and is joined by a joining means such as a connector 53, the connector means for receiving a signal from the outside is connected to the second control circuit board 52 in a compact and centralized manner. There is.

The second control circuit board is mainly provided with a controller for controlling the control related to image formation, and has a memory expansion circuit 54 including, for example, a RAM or the like and an interface expansion having a connection interface function with an external device. The circuit and the like are configured to be detachable from the left end side of the device.

By the way, the first control circuit board 51 is disposed between the main chassis 100 made of metal sheet metal and the lower shield plate 55 made of metal sheet metal arranged at the lowermost end portion of the device to enhance the device rigidity and to have a shielding function. Has been placed,
Intrusion of electromagnetic noise from the outside or outflow of electromagnetic noise to the outside is prevented.

In the main chassis 100, the upward squeezing portion 10 corresponding to a component having a large mounting height such as a power transformer mounted on the first control circuit board 51.
0a is formed to improve the plane accuracy and rigidity of the main chassis 100, hold the fixing unit 60, the paper feeding unit 70, the transfer unit 80, and the like in a stable relationship, and also to control the first control circuit board. The mounting space of 51 is effectively produced, which contributes to the miniaturization of the entire apparatus.

The first control circuit board 51 needs to be connected to each mechanical section, and the wiring connector 10 provided at the end of the lead wire of the drive motor 103 for simplifying the connection.
3b and the like are intensively connected, or the lead terminals 57 having elasticity are pressed to be electrically connected to each other to electrically connect to respective points.

On the other hand, the second control circuit board 52 is arranged to face the main chassis 100 made of metal sheet metal, and
It is protected by a shield case that surrounds the periphery thereof, and like the first control circuit board 51, electromagnetic wave noise intrusion from the outside or electromagnetic wave noise outflow to the outside is prevented.

From here, referring to FIG. 2 and FIG. 4, FIG. 5 and FIG. 6, FIG. 7, FIG. 8, FIG. 9, FIG. 10, FIG. explain.

The main part of the drive transmission portion of this embodiment is the second control circuit board 5 with the first control circuit board 51 substantially at the center.
The wheel train first receiver 101 and the wheel train second receiver 1 are centrally arranged on the right side surface of the main chassis 100 on the side opposite to the side 2.
02 are provided in opposition to each other, and a drive motor 103 having a drive gear 103a on an output shaft and a plurality of drive gear trains described in detail later are rotatably supported by these two train wheel receivers to form a unit structure. Main chassis 100 that is the basis of the configuration
The position of the screw 10 is adjusted to a predetermined position by engagement (not shown) of the positioned portion with the positioning portion formed on the screw 10.
It is fixed by fixing means such as 4.

In this embodiment, the train wheel first receiver 101 and the train wheel second receiver 102 are made of sheet metal, and as will be described later in detail, there is provided means for inexpensively constructing the characteristics. Is a feature.

In this embodiment, the first control circuit board 5 is used.
1 is arranged immediately below the above-mentioned sheet material conveying path with its plane area being substantially the same as that of the sheet material conveying path, and the second control circuit board 52 and the main part of the drive transmission portion are separated from this sheet material conveying path region. The sheet materials are arranged on one side and the other side, respectively, which are orthogonal to the sheet conveying direction, which contributes to downsizing of the device, which pursues the reduction of space space to the limit, and in particular to reduction in the height direction.

Further, regarding the disposition of the toner tank 20 described above, as in the case of the main parts of the second control circuit board 52 and the drive transmission portion, as shown in FIG. 2, it is orthogonal to the sheet material conveying direction deviated from the sheet material conveying path area. In addition to being placed on one side, it can be mounted so as to project from the outer case of the apparatus, which not only contributes to downsizing of the apparatus in order to reduce the space space, but also the outer case and the like when mounting the toner tank 20. It does not need to be released and is extremely easy to wear.

The entire drive system of this embodiment will be described with reference to FIGS. 4 and 5. 4 and 5 show a suitable embodiment of a drive system used in the image forming apparatus of the present invention, and each drawing is a cross-sectional view at a different position. In FIGS. 4 and 5, the rotation center position of each gear is shown. Is marked with + in the figure.
(The same applies to FIG. 7) First, referring to FIG. 5, regarding the drive system of the present embodiment, individual drive starting from the common A # gear driven by the drive gear 103a provided on the output shaft of the drive motor 103 Explain by system.

<First Drive System> The first drive system for rotationally driving the photosensitive drum 1 is A # gear → J # gear → K #.
The L # gear is driven in the order of gears → L # gear, and the L # gear is a gear fixed to one end of the photosensitive drum 1 by a fixing means such as an adhesive. , Connect to or disconnect from this first drive system.

The attachment / detachment of the cartridge of this embodiment is performed by moving the cartridge in the vertical direction in the figure.

<Second Drive System> The second drive system for rotationally driving the developing roller 12 which is the main constituent member of the developing unit 10 is A # gear → B # gear → C # gear → D # gear → E.
The #G gear is driven in this order, and the E # gear is rotatably supported by the cartridge lower case 18 at substantially the same axial center position as the developing roller 12, which will be described in detail later. The configuration is such that drive force is transmitted to an F # gear fixed to a projecting end of a supporting portion 12a extending to one end side of the developing roller 12 by a fixing means such as press-fitting. 2 Connect to or disconnect from the drive system.

<Third Drive System> The third drive system for rotationally driving the supply roller 13, which is the main constituent member of the developing unit 10, is driven in the order of F # gear → G gear → H # gear, and H The # gear is a gear fixed to the protruding end of the support portion 13a extending to the one end side of the supply roller 13 by a fixing means such as press fitting.

<Fourth drive system> The drive means 25 for driving the endless coil springs 31 and 31a for circulating and conveying the toner and the agitator 2 of the toner tank 20 are described.
A fourth drive system for rotating 3 is shown in FIGS. 4 and 7, and is driven in the order of E # gear → M gear → N # gear,
The N # gear is a helical gear fixed to one end side of the driving means 25 by a fixing means such as press fitting,
The M # gear that drives this is a helical gear that is rotatably supported by the cartridge lower case 18 described above.

<Fifth Drive System> A fifth drive system for rotationally driving the paper feed roller 73 is shown in FIG.
The B # gear, the C # gear, the P # gear, the Q # gear, and the R # gear are driven in this order, and the R # gear is a gear mounted on the clutch disposed on one end side of the above-described paper feed roller 73, and is always It is connected to the fifth drive system.

<Sixth Drive System> The sixth drive system for rotationally driving the fixing roller 63 is A # gear → S # gear → T.
The gears are driven in the order of # gear → U # gear, and the U # gear is a gear mounted on one end side of the fixing roller 63 described above.

<Seventh drive system> The pair of paper discharge rollers 61 described above.
The seventh drive system for rotationally driving is driven in the order of U # gear-> V # gear-> W # gear, and the W # gear is a gear mounted on one end side of the paper discharge roller pair 61.

Next, the main part of the drive system will be described in detail.

<First drive system> A # gear → J # gear → K
The first drive system for rotationally driving the photosensitive drum 1 driven in the order of # gear → L # gear has a structure shown in detail in FIG. 6, and FIG. 6 is an exploded sectional view of this first drive system.

The drive gear 103a provided on the output shaft of the drive motor 103 mounted on the first train wheel train receiver 101 faces each of the first train wheel train receiver 101 and the second train wheel train receiver 102 and has a mirror-like outer peripheral portion. A rotatably supported by the projection portions 101a and 102a formed in the state
The # gear is driven, and the K # gear is driven via the J # gear rotatably supported by the projection unit 101b formed on the first train wheel bridge receiver 101 with the outer peripheral portion being in a mirror surface state. Leading to.

Incidentally, the J # gear is the projection unit 101.
The bush 105 attached to the protruding end of b prevents the projection portion 101b from being detached.

Regarding the K # gear support structure, A #
Similar to the gears, the train wheel first receiver 101 and the train wheel second receiver 10
It is rotatably supported by projection portions 101c and 102c formed so as to face each of the two and have an outer peripheral portion in a mirror-like state, and has an extremely simple and inexpensive structure in which a support shaft, a bearing member and the like are unnecessary. .

On the other hand, the first train wheel bridge receiver 1 provided opposite to each other.
01 and the projection unit 10 of the train wheel second receiver 102
1a and 102a, projection units 101c and 102
c, the relative positional relationship between the projection portion 101b and the corresponding relative positional relationship must be ensured so that each gear can rotate stably, and in the present embodiment, in order to achieve the above object, A plurality of projection parts 101d from the first receiving part 101 and a plurality of projection parts 102d from the second train wheel second receiving part 102 are provided so as to face each other, and an engaging recessed part 101e is provided at a projection end of the projection part 101d.
At the projection end of the projection portion 102d.
01e is formed to engage with each other to perform positioning, and the first and second wheel train bridges 10 are formed by engaging both of them.
1 and the second train wheel bridge receiver 102 are united by a screw 106 while maintaining a predetermined positional relationship and a relative interval.

Regarding the engaging concave portion 101e or the engaging convex portion 102e, although not shown, the engaging concave portion is the projection portion 102d, the engaging convex portion is the projection portion 101d, or the contrary to the above configuration. , The plurality of projection units 101d and 102d may be configured by combining the above-mentioned contents, and the projection units 101a and 1a of the train wheel first receiver 101 and the train wheel second receiver 102 may be combined.
02a, the projection portions 101c and 102c, and the projection portion 101b have a predetermined relative positional relationship easily by pressing the train wheel first receiver 101 and the train wheel second receiver 102 of the sheet metal structure with a progressive die or the like. Is configurable.

The above structure has been described by taking the above-mentioned first drive system as an example, but in the present embodiment, although not shown in the drawings, it is also applied to the other drive systems described above.

The drive motor 103 of this embodiment is
An inexpensive PM type stepping motor is used, and smooth continuous rotation drive is possible by controlling the input pulse and current.

<Second Drive System> and <Third Drive System> The developing roller 12 which is a main constituent member of the developing unit 10 described above.
The main parts of the second drive system for rotationally driving and the third drive system for rotationally driving the supply roller 13 are the structures shown in detail in FIGS. 10, 11, 12 and 13, and FIG. FIG. 11, FIG. 12 and FIG. 13 show another embodiment, and the points of FIG. 11, FIG. 12 and FIG. 13 which are different from FIG. 10 are shown in section AA and section BB in the figure. Since the other parts are configured in the same manner, they will be described using the same reference numerals.

The D # gear of the second drive system, which is driven in the order of A # gear → B # gear → C # gear → D # gear → E # gear, has been described by taking the first drive system as an example. Similar to the gear, the first train wheel receiver 101 and the second train wheel receiver 102 are rotatably supported by projection portions 101f and 102f that are formed so that their outer peripheral portions are mirror-finished and face each other. The E # gear, which is connected to or detached from the D # gear by attachment / detachment, is firmly connected by a fixing means such as a screw via the connecting member 6 described above with reference to FIGS.
a and a supporting member 5 rotatably supported by the supporting pin 5Aa, and a fixing means such as press-fitting to a projecting end of a supporting portion 12a extending to one end of the developing roller 12 rotatably supported by the supporting member 5A. F fixed by
Opposed to the # gear, it is rotatably supported by a support shaft 19 provided by a fixing means such as press-fitting in a cartridge lower case 18 at an axial center position of the developing roller 12.

Similarly, the H # gear fixed to the projecting end of the supporting portion 13a extending to one end of the supply roller 13 rotatably supported by the supporting member 5 and the supporting member 5A by a fixing means such as press fitting. Is a configuration in which the drive is transmitted from the F # gear to the H # gear via the G # gear rotatably supported by the shaft portion 5b protruding from the support member 5,
The developing roller 12 and the supply roller 13 are rotatably supported by the support member 5 and the support member 5A, and together with the above-mentioned regulation blade 14, the support pin 5a and the support pin 5Aa.
Is integrally rotatably supported by the developing roller 12 by the springs 8 and 8A for biasing the developing roller 12 toward the photosensitive drum 1 as described above with reference to FIGS. 3, 8 and 9. The pressure roller 1 is in pressure contact with 1 to form a stable nip portion, and the position of the developing roller 12 is influenced by, for example, the outer diameter of the photosensitive drum 1 and the developing roller 12, variations in the rotational axis center deviation, and the like.

Therefore, in this embodiment, from the E # gear to the F
In order to stably transmit the rotational driving force to the # gear, in the embodiment of FIG. 10, the convex portion E parallel to the line symmetry orthogonal to the rotation axis is formed on the BB cross section of one E # gear. #A is formed, and a convex portion F # a parallel to the rotational axis which is orthogonal to the axis of rotation is formed in the A-A cross section of the other F # gear. #A which engages with #a and which is slidable and is orthogonal
A so-called universal coupling 110 for transmitting the rotational driving force from the E # gear to the F # gear in the direction of the arrow in the drawing is formed with the piece member 26 having a and 26b interposed therebetween.
In addition to absorbing the misalignment of the rotational shafts of the gear and the F # gear, for example, in the case of gear meshing drive, the nip portion formed by pressing the developing roller 12 and the photosensitive drum 1 by the axial force generated by the pressure angle It becomes unstable,
In the present embodiment, the above phenomenon is reduced.

In this embodiment, in order to facilitate the assembling of the universal coupling 110, a contour portion E # b is formed in the BB cross section of the E # gear, and the concave portion 26a is formed in the convex portion E # a. The piece member 26 engaged with is prevented from coming off, and when the F # gear protruding toward the E # gear side from the members such as the H # gear and the G # gear near the F # gear is slid in the radial direction, it is projected. This facilitates engagement with the portion F # a.

By the way, the universal coupling 110 constructed as shown in FIG. 10 has the above-mentioned points, but the improvement of drive transmission efficiency and the reduction of the axial force can be achieved by the convex portion E # a of the E # gear and the piece member. 26 of 26 and piece member 26
This is achieved by reducing the sliding friction loss between the concave portion 26b and the convex portion F # a of the F # gear and by effectively transmitting the driving force.

Therefore, in another embodiment shown in FIG. 11, a concave portion having planes E # c which are parallel to each other and symmetrical about the rotational axis is formed in the BB cross section of one E # gear and the other F gear is formed. # The planes F # which are parallel to each other and are symmetrical with respect to the rotation axis center point in the AA cross section of the gear
a concave portion having c is formed, and a piece member 27 having convex portions 27a and 27b intervening by engaging the concave portion having both surfaces E # c and the concave portion having surface F # c is interposed. A universal coupling 110 for transmitting a rotational driving force from the E # gear to the F # gear in the direction of the arrow in the figure.
10 and achieves the same operation as described above with reference to FIG. 10. Particularly, in the structure shown in FIG. 11, rotational drive transmission from the surface E # c to the convex portion 27a and transmission from the convex portion 27b to the surface F # c.
As for the rotational drive transmission to the rotary drive transmission, the operating directions at the operating points of the rotational drive transmission are matched with the respective rotational directions, and the transmission efficiency is good.

Further, in the structure of FIG. 11, E # gear and F #
The # gear is formed of a resin such as polyacetal having a high slidability, and the piece member 27 is formed by die casting of zinc, aluminum, brass or the like to improve the sliding compatibility with the plastic.

In the embodiment of FIG. 11, as in the embodiment of FIG. 10, as a consideration of facilitating the assembly of the universal coupling 110, a contour portion E # b is formed in the BB cross section of the E # gear. And the convex portion 27a is formed in the concave portion having the surface E # c.
Is prevented from falling off, and the F # gear protruding toward the E # gear from the members such as the H # gear and the G # gear near the F # gear is slid in the radial direction, The concave portion having the F # gear surface F # c facilitates the engagement of the piece member 27 with the convex portion 27b. (At the time of this engagement, the convex portion 27b of the piece member 27 can enter and be set at a predetermined position while rotating the E # gear from one outer side of the continuous concave portion having the surface F # c.) Now, another improved embodiment will be described with reference to FIG. In another embodiment shown in FIG. 12, planes E # d which are parallel to each other symmetrically about the axis of rotation of the one E # gear at the BB cross section.
And a concave portion having a surface F # d parallel to each other in a rotational axis symmetry with respect to the axis AA of the other F # gear, and a concave portion having both surfaces E # d. Face F # d
The rotary driving force is transmitted from the E # gear to the F # gear in the direction of the arrow in the drawing through the intermediation of the piece member 28 which is engaged through the roller 29 rotatably supported in the recess having The so-called universal coupling 110 is configured to perform the same operation as described above with reference to FIG. 10, and in the structure shown in FIG.
With respect to the rotation drive transmission to the roller 9 and the rotation drive transmission from the roller 29 to the surface F # d, the action directions at the action points of the rotation drive transmission coincide with the respective rotation directions, and the transmission efficiency is good, and Sliding friction loss that occurs when the member 28 moves is extremely small due to rolling friction.

Further, in the structure of FIG. 12, the roller 29 is made of a resin such as polyacetal having a high slidability, and the piece member 2
7 is formed by die casting of zinc, aluminum, brass or the like to improve the sliding compatibility with plastic.

In the embodiment of FIG. 12, the surface E # d formed on the BB cross section of the E # gear is taken into consideration to facilitate the assembly of the universal coupling 110 as in the embodiment of FIG. The recessed portion has a discontinuity to prevent the piece member 28 engaged through the roller 29 from falling off.
When the F # gear that protrudes toward the E # gear from the members such as the H # gear and the G # gear near the gear is slid in the radial direction, the concave member having the F # gear surface F # d allows the piece member 28 to rotate. It facilitates the engagement with the roller 29 supported by. (During this engagement, the piece member 28 that rotatably supports the roller 29 may enter and be set at a predetermined position while rotating the E # gear from one outer side of the continuous recess having the surface F # d. Next, another improved embodiment will be described with reference to FIG. Another embodiment shown in FIG. 13 is a structure obtained by further improving the universal coupling 110 having the structure shown in FIG.
Only the part will be explained.

In a further improved embodiment shown in FIG. 13, one E # gear is provided with a concave portion having planes E # d which are parallel to each other and symmetrical with respect to the rotation axis center point, and the other is formed in the BB cross section. F
A concave portion having planes F # d which are parallel to each other and symmetrical with respect to the rotation axis is formed in the A-A cross section of the # gear, and the A-A cross section of the F # gear is formed between the E # gear and the F # gear. A concave portion similar to the surfaces F # d which are parallel to each other in the rotational axis center point symmetry and a surface E # d which is parallel to the rotational axis center point in the BB cross section of the E # gear. Floating member 1 having a similar recess
20 is arranged, and a recess having the surface E # d of the E # gear and a recess similar to the surface F # d of the floating member 120, and a recess similar to the surface Ed of the floating member 120 and the surface F # of the F # gear. Rotate in the direction of the arrow from the E # gear to the F # gear by interposing two piece members 28 that are engaged in the dented portion having d via a roller 29 rotatably supported and are slidable in the orthogonal direction. A so-called universal coupling 110 that transmits driving force is configured to perform the same operation as described above with reference to FIG.
In the structure shown in FIG. 13, regarding the rotational drive transmission from the surface E # d to the roller 29 and the rotational drive transmission from the roller 29 to the surface F # d, the action directions at the action points of the rotational drive transmission are the respective rotation directions. And the transmission efficiency is good, and the sliding friction loss generated when the piece member 28 moves is extremely small because of the rolling friction, and the rotating shaft cores of the E # gear and the F # gear are greatly different. Even if the floating member 120 is not restricted by anything, it floats and rotates flexibly and further stabilizes the nip portion formed by the developing roller 12 and the photosensitive drum 1 being in pressure contact with each other.

The structure of the universal coupling 110 having the floating member 120 is applicable not only to the improvement of the structure shown in FIG. 12 but also to the improvement of the structures shown in FIGS. 10 and 11. .

On the other hand, as in the above-mentioned <first drive system> and <second drive system>, the drive operation of the photosensitive drum 1 and the developing section 10 is dispersed in the drive of the cartridge in this embodiment, and The driven part or the drive part on the main body side does not have to be configured to have high rigidity, and there is no concentrated load condition on the driven part on the cartridge side or the drive part on the main body side. In this configuration, vibration and chattering are suppressed, and driving with little rotation jitter is possible.

Regarding the image forming apparatus or the cartridge of this embodiment described above, the points to be noted here will be summarized as follows.

<Regarding Cartridge Structure and Driving Relationship> The main parts of the image forming means are the photosensitive drum 1, charging roller 2, cleaner section 90, developing section 10, toner conveying section 30,
A book in which the units 30a are arranged in the above-described relationship, and the cartridge lower case 18 mainly responsible for the main part and the cartridge upper case 17 also responsible for the cover thereof are unitized to be detachable from the main body. In the cartridge of the embodiment, the supporting member 5 and the supporting member 5A, which rotatably support both ends of the supply roller 13 and the developing roller 12, which are the main parts of the developing unit 10, are fixed by a connecting member 6 such as screws. 3, the supporting member 5 is rotatably supported by a supporting pin 5a which is inserted through a part of the lower cartridge case 18, as shown in FIG. Although only one side is supported, the other side has the same support structure. The support member 5A shown in FIG. Similar support pins 5A which is arranged in the same cross-sectional position and support pins 5a shown in FIG. 3 by inserting a portion of the
It is rotatably supported by a, and is configured with the above-mentioned regulating blade 14 as a supporting shaft with the supporting pin 5a and the supporting pin 5Aa as a supporting shaft so that the storage amount is kept to the minimum necessary amount that does not hinder the image forming process. Toner storage unit 1
1 is configured to be rotatable integrally with the photosensitive drum 1 in the space of 1, and as described above with reference to FIGS. 3, 8 and 9, the spring 8 for biasing the developing roller 12 toward the photosensitive drum 1 is used. And 8A, the developing roller 12 moves the photosensitive drum 1
The position of the developing roller 12 is influenced by, for example, the outer diameter of the photosensitive drum 1 and the developing roller 12, variations in the rotational axis of the rotary shaft, and the like.

The supply roller 13 and the developing roller 1 are also
An H # gear and an F # gear are provided at one end of each of the two, and the H # gear is connected to the F # gear via a G # gear that is rotatably supported by a shaft portion 5b provided on the support member 5. Drive is transmitted from.

The E # gear for transmitting the rotational driving force to the F # gear is provided by a fixing means such as a press fit in the cartridge lower case 18 which is opposed to the F # gear and is substantially coaxial with the developing roller 12. It is rotatably supported by the supporting shaft 19, and the F # gear and the E # gear are shown in FIGS.
1, the so-called universal coupling 110 described in detail with reference to FIGS. 12 and 13 can be configured to drive by absorbing the misalignment of the rotational axes of the E # gear and the F # gear.

As described above, the photosensitive drum 1 is equipped with the L # gear as the driven means, and the cartridge lower case 18
Is equipped with an E # gear as a driven means for the supply roller 13 and the developing roller 12, and a K # gear, a D # gear, etc. are provided as means for driving the supply roller 13 and the developing roller 12 according to the attachment / detachment of the cartridge. Are configured to be engaged or disengaged correspondingly to each other, and are configured to be driven in a driven and driven relationship in the mounted state, and to drive the photosensitive drum 1 and the developing unit 10. The positions of action are dispersed,
Since the concentration of the driving force is not concentrated, the driven part on the cartridge side or the driving part on the main body side does not have to be upsized or have high rigidity.

Further, according to the above configuration, the conventional USP
As shown in 4835565, a plurality of adjoining rotating bodies are arranged in a developing unit that is movable toward and away from the photoconductor and is biased and pressed against the photoconductor.
One of the rotating bodies is supported so as to be relatively movable toward and away from it, and the movable body is movable toward and away from the end of the gear shaft driven by an idle gear that is provided in the developing unit case and driven from the main body. Unlike the drive structure driven by a coupling means such as an Oldham's joint, the cartridge lower case 18 in which the photosensitive drum 1 is rotatably supported is driven by the supply roller 13 and the developing roller 12 in this embodiment. E # gear is equipped as a means.
The structure is such that the # gear is driven by the D # gear mounted on the main body side, and the F # gear that is rotatable about the support pins 5a and 5Aa is not driven from the main body side. The phenomenon that the developing roller 12 and the photosensitive drum 1 are brought into pressure contact with each other to make the nip portion unstable due to the axial force generated by the pressure angle at the time of meshing is reduced.

Since there is no concentrated load on the driven part on the cartridge side or the drive part on the main body side,
Vibration and chatter are suppressed, driving with little rotation jitter is possible, and extremely stable image formation with little pitch variation and density variation of the image is performed, which is particularly effective for a high-resolution image forming apparatus.

Further, as described above, the developing unit 10 of the present embodiment.
The main part of the toner is rotated in the space of the toner storage unit 11 which is supported by the cartridge lower case 18 and has a minimum storage amount that does not hinder the image forming process with the support pin 5a as a support center. It has a structure in which it is dynamically moved and urged to move appropriately, and it has a toner hopper for storing a desired amount of toner in the developing portion as shown in the conventional example of Japanese Patent Publication No. 63-67185. Unlike the developing unit supported by inclusion, the supporting state of the developing unit does not change according to the change in the toner amount, and the relationship between the photosensitive drum 1 and the developing unit does not become unstable.

On the other hand, in the above-mentioned configuration of the present embodiment, the main portion of the developing unit 10 from the photosensitive drum 1 is set in the space of the toner storage unit 11 which is configured to have the necessary minimum storage amount that does not hinder the image forming process. The above-mentioned effect is explained based on the structure in which the toner is replenished to the toner storing portion 11 from the toner conveying portion 30a by the rotational movement of the portion and the corresponding movement. Toner transporting section 3 in section 11
It is not limited to the configuration in which the toner is replenished from 0a, and even in the structure in which a desired amount of toner is accommodated in the toner hopper as in the conventional example, in the toner hopper, the above-mentioned developing unit is The same effect can be obtained even if the structure is urged to rotate and moves accordingly.

Here, focusing on the drive relationship between the photosensitive drum 1 and the main part of the developing section 10, the developing section 1 of the present embodiment.
The main part of 0 is a structure which is supported by the lower cartridge case 18 and is urged to rotate and move about the support pins 5a and 5Aa as support centers. When the F # gear is driven via the universal coupling 110, each rotated body is driven in the direction of the arrow shown in FIG. 3, and is driven in this direction by the universal coupling 110 described above with reference to FIGS. Then, at a position away from the support pins 5a and 5Aa, E #
From the gear via universal coupling 110 to F #
The developing roller 1 is driven by the moment the gear is driven.
2, the developing unit 10 of the supply roller 13 and the regulating blade 14
The developing roller 12 is pressed against the photosensitive drum 1 by a moving force acting in a direction away from the photosensitive drum 1 in balance with the pressing force of the springs 8 and 8A to form a nip portion. Even if the driving torque changes due to changes in humidity or deterioration of durability, the developing roller 12 has a tendency to move in a direction away from the drum 1, so that the nip portion does not become unstable due to a biting phenomenon or chattering.

On the other hand, at a position away from the support pins 5a and 5Aa, the universal coupling 1 is moved from the E # gear to the universal coupling 1.
Due to the moment that the F # gear is driven via 10, the moving force that acts on the developing roller 12, the supply roller 13, and the main portion of the developing portion 10 of the regulating blade 14 in the direction away from the photosensitive drum 1 is simply F #. Compared to a structure in which gears are driven by gears, the structure is extremely small and stable with little fluctuation, and the stability of the nip portion is excellent.

The moving force is the same as that of the support pin 5 shown in FIG.
The distance between a and the developing roller 12 can be made smaller as it is made larger, and when this distance is set to a desired size and driven, the developing roller 12, the supply roller 13, and the regulating blade 14 are not necessarily removed from the photosensitive drum 1. The support pin 5a is provided at a position where a moving force acts in a direction in which the main part of the developing unit 10 separates.
It is possible to form a stable nip portion without arranging 5Aa and 5Aa. Although the arrangement of the support pins 5a and 5Aa is omitted in the drawing, it may be located below the developing roller 12 in FIG. .

In this embodiment, the developing roller 12 and the supply roller 13 are used for the main part of the developing unit 10. However, the supply roller 13 is not an essential condition of the above structure, but a one-component magnetic toner is used. Even if the developing unit 10 has a structure in which the main part of the developing unit 10 is composed of only the developing roller 12 as in the conventional example represented by the structure of the developing unit, the photosensitive drum 1 is not limited to the cylindrical drum shape. Not
Although not shown, for example, the above-described effects can be exhibited even with an endless belt-shaped photoreceptor.

The main part of the developing section 10 of this embodiment is
The relationship between driving and driven is explained based on the structure of being supported by the lower cartridge case 18 and being pivotally moved about the supporting pin 5a to perform a corresponding movement. On the other hand, this is an example in which the main part of the developing unit 10 can be moved relatively in position and can be configured in a small size, and is driven by the so-called universal coupling 110 described in detail with reference to FIGS. 10, 11, 12 and 13. With regard to the above, the above-described structure is not an essential condition, and the above-described effect is applied as long as it is a rotational drive for a rotating body that is configured to be movable relative to the photosensitive drum 1.

Further, in the present embodiment, the main parts of the image forming means such as the photosensitive drum 1, the charging roller 2, the cleaner section 90, the developing section 10, the toner conveying sections 30 and 30a are the cartridge lower case 18 and the cartridge upper case 17. It is configured so that it can be attached to and detached from the main body as a cartridge that is housed in a unit structure and is removably attached to the main body. In this embodiment, which has the above-described structure, there is no problem even if the cartridge structure is not detachable from the main body as described above but the structure is integrated with the main body.

[0128]

As described above, the cartridge of the present invention,
In the image forming apparatus, the cartridge that is detachable from the main body of the image forming apparatus includes a photosensitive member that has a driven member that is driven to rotate by the image forming apparatus, and a latent image formed by exposing the photosensitive member. Developing means having a second rotated driven means for developing and developing the toner to visualize the toner, supporting means for supporting the developing means, and first rotated driven means for rotationally driven from the image forming apparatus. A housing for supporting the photoconductor, the developing means and the first rotationally driven means, and a biasing means for pressing and biasing the developing means toward the photoconductor, and the supporting means rotates about a fulcrum. The second rotationally driven means is movably supported and is configured to be rotationally driven from the first rotationally driven means via a universal coupling.
Since the image forming apparatus is configured to include the rotation driving unit that rotationally drives the photoconductor and the developing unit, the driving action positions of the photoconductor and the developing unit are dispersed, and the concentration of the driving force is avoided. Since the driven part on the cartridge side or the drive part on the main body side does not need to be large in size or configured to have high rigidity, simplification of the device is extremely easy, and a compact structure and an inexpensive structure are provided. Is beneficial to
From the rise of small notebook type computers of recent years, downsizing has been spurred more and more, and the appearance of small and inexpensive printers and facsimiles that can be arranged with plenty of space on the personal desk suitable for the expanding personal use market has become possible. Since there is no load condition concentrated on the driven part on the cartridge side or the drive part on the main body side, not only vibration and chatter are suppressed and driving with less rotation jitter is possible, but also relative to the photoconductor. The developing means, which is rotatably supported and rotatably supported about a fulcrum, is rotationally driven from the first rotationally driven means supported by the housing through the universal coupling, so that the gear meshes. The phenomenon in which the nip portion formed by the developing means and the photosensitive member being in pressure contact with each other is unstable due to the axial force generated by the pressure angle is reduced. Further support structure developing unit is pivotally supported about a fulcrum to be moved relative to the photosensitive member is easy to miniaturize configuration not only can be constructed at low cost easy to very structure.

On the other hand, when the fulcrum position of the supporting means is arranged at a position where this driving force acts in the direction of separating the developing means from the photoconductor when the developing means and the photoconductor are rotationally driven, for example, Even if the driving torque changes due to changes in temperature and humidity or deterioration of durability, the nip part does not become unstable due to biting phenomenon or chattering.

The developing means includes a developing roller that is pressed against the photoconductor and rubs to convey the toner to the photoconductor, and a developing roller that rubs the developing roller with a predetermined nip amount. It has a supply roller for conveying toner and a blade for regulating the toner conveyance amount of the developing roller, and is structured so as to be supported and driven so as to be movable relative to the photosensitive member. Since the rubbing state of the roller and the relative relationship between the developing roller and the blade move as a unit, the predetermined relationship is maintained, and the drive torque changes due to changes in conditions such as temperature and humidity changes and durability deterioration. Even so, the above-mentioned change in axial force is small and the nip portion formed by the developing means and the photosensitive member in pressure contact is stable,
An extremely stable image is formed with little fluctuation in the pitch and density of the image, which is a particularly effective technique for a high-resolution image forming apparatus, and the practical effects of the present invention are extremely large.

[Brief description of drawings]

FIG. 1 is a sectional view of a left side main part showing an embodiment of an image forming apparatus of the present invention.

FIG. 2 is a cross-sectional view of a front main part showing an embodiment of the image forming apparatus of the present invention.

FIG. 3 is a cross-sectional view of an essential part of a left side surface showing an embodiment of the cartridge of the present invention.

FIG. 4 shows a first example of an image forming apparatus according to the present invention.
FIG.

FIG. 5 shows a second embodiment of the image forming apparatus of the present invention.
FIG.

FIG. 6 is a developed sectional view showing an embodiment of the image forming apparatus of the present invention.

FIG. 7 is a cross-sectional view of a right side main part showing an embodiment of the cartridge of the image forming apparatus of the present invention.

FIG. 8 is a cross-sectional view of an essential part of a top surface showing an embodiment of the cartridge and the image forming apparatus of the image forming apparatus of the present invention.

FIG. 9 is a cross-sectional view of a main part of the upper surface of a cartridge showing an embodiment of the cartridge of the image forming apparatus of the present invention.

FIG. 10 is a first rotation drive system explanatory diagram showing an embodiment of the cartridge of the present invention.

FIG. 11 is a second rotary drive system explanatory view showing another embodiment of the cartridge of the present invention.

FIG. 12 is a third rotary drive system explanatory diagram showing another embodiment of the cartridge of the present invention.

FIG. 13 is an explanatory view of a fourth rotation drive system showing another embodiment of the cartridge of the present invention.

[Explanation of symbols]

 1 Photosensitive Drum 2 Charging Roller 5, 5A Supporting Member 5a, 5Aa Supporting Pin 8, 8A Spring 10 Developing Section 12 Developing Roller 13 Supply Roller 17 Cartridge Upper Case 18 Cartridge Lower Case 20 Toner Tank 30, 30a Toner Conveying Section 31, 31a Coil Spring 40 Exposure unit 50 Control section 51 First control circuit board 52 Second control circuit board 60 Fixing section 64 Fixing base 70 Paper feeding section 71 Sheet material conveying base 72 Paper feeding tray 73 Paper feeding roller 80 Transfer section 81 Transfer roller 90 Cleaner Part 92 Cleaning blade 100 Main chassis 101 First wheel train receiver 102 Second wheel train receiver 103 Drive motor 110 Universal coupling

Claims (6)

[Claims] 1. A cartridge which is detachable from the main body of the image forming apparatus, and which has a photosensitive member having a rotationally driven unit which is rotationally driven by the image forming apparatus, and a latent image formed by exposing the photosensitive member. Developing means having a second rotated driving means for developing and developing the toner to rotate the toner, supporting means for supporting the developing means, and first rotated driven means for rotating the image forming apparatus. A casing that supports the photosensitive member, the developing unit, and the first rotationally driven unit,
Urging means for urging the developing means toward the photoconductor, the supporting means is rotatably supported about a fulcrum, and the second rotation driven means is 1. A cartridge having a structure in which it is rotationally driven from a rotationally driven means through a universal coupling. 2. A photosensitive member having rotationally driven means that is rotationally driven by an image forming apparatus, and a latent image formed by exposing the photosensitive member to light to develop and visualize the latent image, which is rotationally driven. 2 developing means having rotationally driven means, first rotationally driven means which is rotationally driven by the image forming apparatus, and a housing which supports the photoconductor, the developing means and the first rotationally driven means. Urging means for urging the developing means toward the photoconductor, the supporting means is rotatably supported about a fulcrum, and the second rotation driven means is the first rotating means. An image forming apparatus comprising: a rotation driving unit that is rotationally driven from a rotation driven unit through a universal coupling, and that rotationally drives the photoconductor and the second rotation driven unit, respectively. 3. The fulcrum position of the supporting means is arranged at a position where the driving force acts in a direction of separating the developing means from the photoconductor when the developing means and the photoconductor are rotationally driven. The cartridge according to claim 1, which is characterized in that. 4. The fulcrum position of the supporting means is arranged at a position where this driving force acts in a direction of separating the developing means from the photoconductor when the developing means and the photoconductor are rotationally driven. The image forming apparatus according to claim 2, which is characterized in that. 5. The developing device is rubbed by being pressed against the photoconductor to rub the photoconductor to convey toner to the photoconductor, and rub the photoconductor with a predetermined nip amount.
2. The cartridge according to claim 1, further comprising a supply roller that conveys toner to the developing roller, and a blade that regulates a toner conveyance amount of the developing roller. 6. The developing means is rubbed by being pressed against the photoconductor to rub it, and a developing roller that conveys toner to the photoconductor and the developing roller, which has a predetermined nip amount and rubs.
The image forming apparatus according to claim 2, further comprising: a supply roller that conveys toner to the developing roller, and a blade that regulates a toner conveyance amount of the developing roller.