JPH01155366A - Image forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus such as an electrophotographic copying device, an electrostatic recording device, or a laser beam printer (LBP).

More specifically, the present invention relates to an image forming apparatus of a so-called detachable process cartridge type.

[Conventional technology]

Image forming apparatuses with removable process cartridges are equipped with 5 specific devices among all process devices for image formation, such as image carrier (electrophotographic photoreceptor, electrostatic recording dielectric, etc.), charging device, developing device, and cleaning device. etc., all of them are collectively assembled into a common housing (frame) in a predetermined mutual positional relationship as a unitary unit that can be freely attached to and detached from the main body of the image forming apparatus. .

The maintainability and serviceability of the image forming apparatus is improved by using the above-mentioned process cartridge attachment/detachment system for the image forming apparatus. ), and by attaching a cartridge with a desired function to the main body of the image forming apparatus and using it as a replacement, the image forming apparatus can be used for multiple functions.・It is already in practical use as one of the configuration methods for cheap and counterfeit image forming apparatuses.

The cartridge has an opening through which a portion of the image carrier surface of the cartridge faces the outside, and is provided with a protective cover that opens and closes with respect to the opening.

The protective cover is opened when the cartridge is installed in the image forming apparatus, and the predetermined process equipment such as the image transfer means on the image forming apparatus main body is exposed to the image bearing surface facing outside from the cartridge opening. Located opposite.

On the other hand, when the cartridge is removed from the image forming apparatus and stored, it is closed and the image bearing surface portion facing the outside from the cartridge opening is hidden and the image bearing surface portion is protected from damage caused by collisions with other objects and dirt. It serves to protect against stains due to adhesion of substances such as, and deterioration due to exposure to external light.

FIGS. 12(A) and 12(B) show conventional examples of process cartridges as described above.

Reference numeral 100 denotes a process cartridge, and the cartridge of this example includes an electrophotographic photosensitive drum l as an image carrier, a corona charger 2 as a charging device that uniformly charges the circumferential surface of the drum to a predetermined polarity, and a developing device. 3 and the cleaning device 4 are collectively housed in a common housing 10 as a unit that can be freely attached to and detached from the image forming apparatus main body (hereinafter referred to as the apparatus main body), not shown. They are assembled together in a predetermined mutual arrangement relationship.

The cartridge 100 is inserted and mounted in a predetermined manner in a predetermined position within the apparatus main body, and can be freely removed from the apparatus main body.

Reference numeral 5 denotes a drum cover (protective cover) having an arcuate cross section for opening and closing the photosensitive drum lower surface exposure opening 11 provided on the lower surface side of the housing.
Swinging arm 13 that can freely rotate around (Fig. 12 (B))
The free end 14 of the arm engages and supports the rear side end of the drum cover 5 in a freely rotatable manner, and the pin shaft 15 provided at the front side end of the drum cover 5 is attached to the free end 14 of the arm. Uzing 1
It is engaged and supported by an arc-shaped guide elongated hole 16 provided on the end plate side of 0. As the swinging arm 13 is rotated counterclockwise about the fulcrum 12, the drum cover 5 is rotated as shown in FIG.
), the opening 11 is moved sufficiently to the right of the opening 11, and the opening 11 becomes open, and conversely, by turning clockwise, it moves to the left, as shown in Figure 12 (B). opening 11
becomes closed.

When the cartridge 100 is removed from the apparatus main body and stored, the drum cover 5 keeps the opening 11 closed as shown in FIG. Protects against damage caused by impact, dirt caused by adhesion of dust, etc., and deterioration caused by exposure to external light.

The cartridge 100 can be installed into the main body of the apparatus by manually opening the drum cover 5, or by inserting the cartridge 100 into the main body of the apparatus.
00 into the apparatus main body, means such as a cam member provided on the apparatus main body side are attached to the drum cover 5 and the swing arm 13.
automatically opens in relation to

Reference numeral 6 denotes a slit-shaped window for exposing a light image formed on the top surface of the housing corresponding to the top surface of the drum l. Reference numeral 7 denotes an opening/closing shutter member for the exposure window 6. Cartridge 10
0 is removed from the device and stored, the first
As shown in Fig. 2 (B), the exposure window 6 is held in a closed state, and the drum surface facing the opening 6 is damaged due to collision with other objects, contamination due to adhesion of foreign matter such as dust, or intrusion. Protect from deterioration caused by exposure to external light.

When the cartridge 100 is fully inserted and installed in the device main body in a predetermined manner, the mechanical drive system and electric circuit system on both sides of the device main body and the cartridge 100 are connected via a mutual coupling member (not shown). Mechanically and electrically integrated.

FIG. 12(A) shows a state in which the cartridge 100 is installed in the main body of the apparatus, and the drum cover 5 is held open from the lower opening 11 of the cartridge lOO, and is exposed from the opening 11. The lower surface of the drum l faces the transfer charger 8 on the apparatus main body side. Further, the shutter member 7 for the exposure window 6 is also held open.

When the copy button is pressed, power is transmitted from a drive source provided in the main body of the apparatus to the drum 1 in the cartridge 100 and the developing roller (of the developing device 3) via a transmission system (not shown).
The developing sleeve/developing cylinder) is transmitted to the drum l.
The developing roller 3a and the developing roller 3a are each driven to rotate in the direction of the arrow (FIG. 12(A)) at a predetermined circumferential speed. Also cartridge 1
Corona charger 2 in 00 and developing roller 3a of developing device 3
A power supply circuit (not shown) is provided on the main body of the copying machine.
A predetermined driving voltage (discharging voltage/developing bias) is applied from there.

During the rotation process, the drum 1 is uniformly charged with a predetermined polarity by the corona charger 2, and is then subjected to light image exposure L (slit exposure of the original image, (laser beam scanning exposure, etc.). As a result, electrostatic latent images corresponding to the exposed image pattern are sequentially formed on the drum circumferential surface. The latent image is then developed as a toner image by the developing device 3, and the developed image is synchronized with the rotation of the drum 1 from a paper feed mechanism (not shown) via a conveyance path, and is transferred between the drum 1 and the transfer charger 8. The image-transferred copying material P is sequentially transferred onto the surface of the copying material P fed between the drums, and is separated from the surface of the drum and introduced into a fixing device (not shown) to undergo image fixation, and the image is fixed. formation (copy)
is output outside the device as On the other hand, the surface of the drum from which the copy material P has been separated after passing through the image transfer section 8 is cleaned by a cleaning device 4.
The cleaning blade 4 made of rubber plate etc. passes through the position of
In step (a), residual toner after transfer and other adhered contaminants are wiped off to form a clean surface, and the surface is repeatedly used for image formation.

In the developing device 3, 3b is a developing device that accommodates the developing roller 3a, 3C is a toner container provided above the developing device 3b, and the toner container 3C is connected to the communication hole 3 provided in the bottom surface of the toner container 3C.
The toner t in the toner container 3c is sequentially conveyed and replenished into the developing device 3b by gravity through the communication hole 3d.

[Problem that the invention seeks to solve]

By the way, regarding the opening/closing protective cover 5 (drum cover) provided in the cartridge 100, the conventional opening/closing mechanism has a swing arm 13, a bearing 12. Guide length 16. It requires many parts such as the engagement pin and the shaft 15, and it takes many man-hours to assemble the cover to the cartridge body, which poses problems in terms of manufacturing and cost.In addition, the opening/closing range of the cover 5 is quite large, which takes up a lot of space. There are problems in that the automatic opening/closing mechanism of the cover 5 is also complicated.

The present invention solves this problem.

[Means for solving problems]

The present invention provides an image forming apparatus in which a process cartridge containing at least an image bearing member is used by being attached to and removed from an apparatus main body, the process cartridge having a cartridge opening through which a part of the surface of the image bearing member inside faces the outside. The protective cover has a protective cover that can be rotated freely to open and close around one axis, and an interlocking mechanism that opens and closes the protective cover once is provided on the central axis of opening and closing of the protective cover and on the side of the main body of the device. This is an image forming apparatus characterized by the following.

[For production]

In other words, by providing the protective cover with respect to the opening as described above so that it can be freely rotated to open and close around one axis, the cover opening and closing mechanism is basically made up of two parts: the center shaft for opening and closing the cover and its bearing. Since it can be easily constructed using only parts, the number of parts and the number of assembly steps are reduced, and problems in terms of manufacturing and cost are solved. Furthermore, since the range of opening and closing rotation of the cover is reduced, space constraints are alleviated and the cartridge can be made smaller. Since it is possible to open and close the cover with a small torque, the mechanism for automatically opening and closing the cover during the process of attaching and detaching the cartridge to the main body of the image forming apparatus or after attaching the cartridge can be done using the simple interaction described above. It can be constructed with good reliability using an interlocking mechanism, and the means mechanism can be simplified.

〔Example〕

1 and 2 are cross-sectional side views of one embodiment of a process cartridge according to the present invention, in which FIG. 1 shows a state in which the protective cover is closed, and FIG. 2 shows a state in which the process cartridge is installed in the image forming apparatus main body. The protective cover is shown open. Conventional cartridge 1 shown in Figure 12 (A)-(B) above
Components common to 00 are given the same reference numerals and repeated explanations are omitted.

The photosensitive drum 1 as an image bearing member is arranged on the right side in the cartridge housing 10, and its right side faces outside from the opening 11 on the right side of the housing 10 as an image transfer process section. When the apparatus is taken out from the main body and stored, the protective cover (drum cover) 5 is closed to the opening 11 as shown in the first figure, and the surface of the photosensitive drum facing outside from the opening 11 is protected from other objects. This protects the device from damage caused by collision with objects, dirt caused by adhesion of dust, etc., and deterioration caused by exposure to external light.

The left side of the photosensitive drum l is provided as a photoimage exposure process section 19, and when the cartridge 100 is installed in the image forming apparatus main body 1 as shown in FIG. It is irradiated with optical image exposure light L (slit exposure of an original image, laser beam scanning exposure, etc.) that enters the housing opening substantially horizontally through a slit-shaped exposure window 6 provided on the left side of the IO.

The cleaning device M4 and the developing device 3 have a substantially horizontal optical image exposure optical path 17 from the exposure window 6 toward the optical image exposure process section 19 of the photoreceptor l, and a reproducing device 4 is provided above and below the optical path.・
They are arranged vertically close to each other as much as possible to ensure a required gap space 18 for the optical path 17 between the three.

The charging device i2 in this example is a contact charging roller or a frictional charging roller, and the bottom surface of the cleaning device 4 is recessed upward at a portion near the photosensitive drum l, and is disposed within the recessed portion 20. The direction of rotation of the photosensitive drum (
It contacts the photosensitive drum surface at a position on the upstream side (counterclockwise). Charger M2 may be a corona charger.

A cleaning blade 4a made of rubber acid or the like of the cleaning device 4 is in contact with the upper surface of the photosensitive drum on the upstream side of the charging roller 2 in the rotational direction of the photosensitive drum.

The developing roller 3a of the developing device 3 contacts or faces the lower surface of the photosensitive drum on the downstream side of the photosensitive drum rotation direction from the photoimage exposure process section 19 with a predetermined small gap therebetween.

In the state shown in FIG. 2 in which the Gartridge 100 is installed in the main body of the apparatus, the drum cover 5 is opened and is exposed to the right side surface of the photosensitive drum 1, which is the image transfer process section side, exposed to the outside through the housing opening IT. A transfer charger 8 on the apparatus main body side is located opposite to the transfer charger 8 . Also, the device body and cartridge 10
The mechanical drive system and electric circuit system on both sides of 0 are coupled via mutual coupling members to become mechanically and electrically integrated.

When the copy button is pressed in the installed state shown in Figure 2,
The photosensitive drum 1, the charging roller 2, the developing roller 3a, and the toner stirring rod 3e are each driven to rotate in the direction of the arrow. The charging roller 2 may be rotated, rotated, or not rotated by the photosensitive drum 1, or may be driven to rotate in the opposite direction. Further, required voltages (charging voltage, developing bias) are applied to the charging roller 2 and the developing roller 3a, respectively.

The rotating photosensitive drum 1 is uniformly charged positively or negatively by the charging roller 2 and subjected to photoimage exposure in the photoimage exposure process section 19 to form a latent image, and the latent image is transferred to the developing roller 3.
It is developed as a toner image in step a. Then, the toner images are sequentially transferred to the surface of a copying material P fed from a paper feeding mechanism (not shown) between the photosensitive drum 1 and the transfer charger 8 in an image transfer process section. After receiving the image transfer, the copying material P separated from the surface of the photosensitive drum is conveyed to a fixing device (not shown), where the image is fixed, and is discharged as a copy. After the image has been transferred, the surface of the photosensitive drum 1 is wiped off by the blade 4a of the cleaning device 4 to remove residual toner and other deposits, thereby making it a clean surface, and the surface is repeatedly used for image formation.

The developing device 3 includes a developing device 3b that accommodates a developing roller 3a.
and a toner container 3C connected to the left side thereof,
The developing device 3b and the toner container 3C communicate with each other via a communication hole 3d provided in a partition wall between the two. The toner t in the toner container 3b is stirred by the stirring rod 3e being driven to rotate at a predetermined speed, and a portion of the stored toner is removed from the communication hole 3d by the scoop sheet member 3f provided at the tip of the stirring rod. The toner is intermittently fed and replenished into the developing device 3b every rotation of the stirring rod 3e.

FIG. 3 shows the waste toner conveyance state within the cleaning device 4. As shown in FIG. The cleaning blade 4a is attached to the photosensitive drum 1
It is in contact with the upper surface of the drum in the counter direction with respect to the rotational direction of the drum. Further, a waste toner scooping sheet (flexible elastic thin sheet) 4b is disposed on the upstream side of the cleaning blade 4a in the rotational direction of the photosensitive drum in the forward direction with respect to the rotational direction of the drum. The upper surface is the inwardly curved inner surface 4 of the casing front wall of the cleaning device 4
It is connected to c.

The transfer residual toner ta on the surface of the photosensitive drum 1 passes through the lower surface side of the waste toner scooping sheet 4b and passes through the cleaning blade 4.
The waste toner tb is scraped off at the edge part a and successively accumulates between the edge part and the scooping sheet 4b. The accumulated waste toner tb is then scraped off from the photosensitive drum surface by the edge portion of the blade 4a, and is subjected to a pressing force in the direction of the scooping sheet 4b by the accumulated waste toner, so that the accumulated waste toner tb is scraped off from the upper surface of the scooping sheet 4b and the above-mentioned inward direction. The waste toner is naturally transported upward along the curved inner surface 4C as a guide surface, and accumulates on the upper surface of the blade 4a from the upper end of the curved inner surface 4c. As the amount of accumulated waste toner increases over time, the waste toner accumulation causes the waste toner storage chamber 4d on the opposite side of the blade 4a to collapse in the direction f, and the waste toner tb enters the waste toner storage chamber 4d.

In other words, the waste toner tb scraped off by the edge portion of the blade 4a on the surface of the photosensitive drum 1 is naturally transported and stored in the waste toner storage chamber 4d without any hindrance during the above-described transport process.

FIG. 4 is a perspective view of the opening/closing hinge portion of the cover 5, in which the shafts 5a provided at both ends of the upper side of the cover 5 are connected to the bearing notches WItl0a provided in the left and right end plates of the cartridge housing 10, respectively. The axis of the shaft 5a is parallel to the longitudinal direction of the opening 11 (the direction perpendicular to the generatrix direction of the photosensitive drum 1 or the feeding direction of the copy material P). The cover 5 rotates up and down to open and close around the shaft 5a. The cover 5 is a horizontally elongated plate with a substantially arc-shaped cross section, and when the cover 5 is in the closed state, the concave curved inner surfaces 5b of the left and right sides of the cover 5 are formed into convex curved surfaces corresponding to the concave curved inner surfaces.
is received by the front edge end faces 10b of the left and right end face plates, thereby preventing further rotation in the closing direction. When the cover 5 is fully opened and raised as shown in FIG.
The outer surface of the cover abuts and is received by the upper front surface 10c of the cartridge housing 10, thereby preventing further rotation in the opening direction.

Next, an example of an automatic opening/closing means mechanism for the cover 5 will be explained.

Example-1 (Figs. 5 to 8) In Figs. 5 and 6, 30 is the exterior casing 1.
31 is the inner body frame (device body chassis); 3
Reference numeral 2 denotes a device opening/closing door disposed on the right end side of the exterior casing 30. The chain ring 32 has its lower side connected to an arm plate 31a extending rightward from the main body frame 31, so that it can be raised and lowered freely around a support shaft 33, and the door 32 can be raised and rotated sufficiently. As a result, the right end surface side of the exterior housing 30 is closed by the chain ring as shown in FIG. 5, and the closed state is locked and maintained by a locking means (not shown). When the lock is released and the door 32 is folded down and rotated, the right end side of the exterior casing 30 is opened as shown in FIG. 6, and the inside of the device is opened. This door is opened and closed when installing and removing the process cartridge 100 into the apparatus main body, troubleshooting jam troubles, inspecting the inside of the apparatus, and the like.

Reference numeral 34 indicates three post parts protruding outward from the outer surface of the main body frame 31, and reference numeral 35 indicates a lower post part between two post parts 34 (a) and 34 (b) which are in a vertical relationship among the three boss parts. A sliding rod long in the left and right direction is disposed to support the weight of the side post 34(b), and 36 is a holding plate screwed to the three boss parts 34, and this holding plate 36 allows the rod 35 to be moved. It is prevented from coming off outward from between bosses 34 (a) and 34 (b). Figure 7 shows Figure 5 (7)-(
7) Shows an enlarged cross section along the line.

The right end of the rod 35 is provided with an elongated hole 35a, and the rod 35 is connected to the door 32 by engaging the pin shaft 37 on the door 32 side with the elongated hole 35a. The left end of the rod 35 is an upward hook portion 35b.

Reference numeral 38 denotes a rack provided on the main body frame 31, with elongated holes 38a in the left and right direction provided on the rack 38, and the elongated holes 3
It is free to slide in the left-right direction within a range restricted by the pin shaft 39 on the main body frame 31 side that engages with 8a. This rack 38 is constantly subjected to a backward force to the left by a tension coil spring 40.

A pinion 41 is rotatably supported by a bearing on the main body frame 31, and the rack 38 is always engaged with this pinion. When the rack 38 is moved forward to the right, the pinion 41 rotates clockwise, and when the rack 38 is moved backward to the left, it rotates counterclockwise.

When the opening/closing door 32 is closed, as shown in FIG. The edge is cut off from the rear end. Therefore, rack 38
is in a free state and is held in a state in which the right end of the elongated hole 38a is sufficiently retracted to the left by the tensile force of the spring 40 to a position where it is received by the pin shaft 39.

When the door 32 is opened from the closed state of FIG. 5 as shown in FIG. 6, the rod 35 is pulled out and moved to the right by the pin shaft 37 on the door 32 side. Hook part 35 on the left end side of rod 35 in the middle of
The front surface of b comes into contact with the rear end of the rack 38, and as the rod 35 continues to be pulled out to the right, the rack 38 is pushed by the hook portion 35b and moves to the right against the tensile force of the spring 40. When the door 32 is moved forward and opened sufficiently,
The hook portion 35b of the rod 35 is caught and locked by the upper boss portion 34(a) of the upper and lower boss portions 34(a) and 34(b) that guide the rod 35, and at that point, the door 32 is locked. Folding and opening rotation is prevented. Further, the rack 38 is held in a state in which it has moved sufficiently forward to the right until the left end of the elongated hole 38a is received by the pin shaft 39. The pinion 41 rotates clockwise due to the forward movement of the rack 38 in conjunction with the tilt/open rotation of the door 32.

Conversely, when the door 32 is raised and closed as shown in FIG. 6 from the folded-open state shown in FIG. . As the hook portion 35b moves backward to the left as the rod 35 is pushed in, the rack 38 also moves backward to the left by the tensile force of the spring 40 as the hook portion 35b moves backward. The rod 35 is moved back sufficiently to the left until the right end is received by the pin shaft 39.The rod 35 is then pushed to the left as the door 32 is rotated to open and close, and finally The state returns to the state shown in FIG. The pinion 41 rotates counterclockwise as the rack 38 moves backward in conjunction with the opening and closing rotation of the fi 32.

Process cartridge 10 inside the image forming apparatus main body
Attachment and detachment of the cartridge 10 is performed from the right end side of the device exterior casing 30, which is opened by folding down @32 as shown in FIG.
0 with your hand and insert it into the cartridge mounting part in the main body of the apparatus in the direction A of FIG. When fully inserted, the flat plate portion 5c provided at the end of the rotation center shaft 5a of the protective cover 5 of the cartridge 100 is positioned corresponding to the recess 9iI4@1I41a provided on the shaft side of the pinion 41, as shown in FIG. It fits and engages into the concave groove. At this time, the protective cover 5 of the cartridge 100 is still in the closed state.

Next, when the door 32 is closed with respect to the main body of the apparatus, the pinion 41 rotates counterclockwise due to the backward movement of the rack 38 in conjunction with the closing of the chain ring 32, as described above.
With one rotation, a counterclockwise rotational force is applied to the shaft 5a of the cover 5 through the concave groove portion 41a of the pinion and the flat plate portion 5c engaged therewith, and the cover 5 is automatically opened and rotated. As shown in FIG. 5, the right end of the elongated hole 38a of the rank 38
By retreating until it is received by the cover 9, the cover 5 is sufficiently opened and rotated as shown in the second figure, and the open state is maintained as long as the door 32 is closed.

Note that the corona charger 8 for transfer in FIG.
When the door 32 is closed, the cover 5 is placed opposite the opening 11 of the installed cartridge 100 which is automatically opened as described above. Further, an image exposure device, a paper feeding mechanism, a contact device, a driving source, a power source, etc. are also arranged inside the apparatus main body, inside the door 32, etc., but are omitted from the figure.

When the door 32 of the image forming apparatus in which the cartridge 100 is installed as shown in FIG. 5 is fully tilted open as shown in FIG. The pinion 41 rotates clockwise, and the rotation of the pinion 41 causes the concave groove 41a of the pinion to rotate.
The cover 5 is inserted through the flat plate portion 5c that engages with the cover 5c.
A clockwise rotational force is applied to the shaft 5a, and the cover 5 is automatically rotated to close.The operator inserts the cartridge 100 with the cover closed into the mounting direction A in FIG. is pulled out in the opposite direction B.

Example 2 (Fig. 9) In this example, a gear G1 is integrally attached to the shaft end of the opening/closing central shaft 5a of the cover 5, and when the cartridge 100 is installed in the image forming apparatus main body, the above-mentioned Gear G1 is brought into mesh with motor gear G2 provided on the device main body side. For example, based on the door closing operation detection signal from the opening/closing operation detection means of the device opening/closing door 32, the motor M is energized for normal rotation, and the gear G2 is rotated by a predetermined angle in the direction of the arrow a. The gear Gl, that is, the shaft 5a, is rotated counterclockwise, and the cover 5 is automatically rotated open about the shaft 5a and held in the open position shown in the second figure. In this cover open state, the motor M is energized in the reverse direction based on the door opening operation detection signal from the detection means, and the gear 02 is reversely rotated by a predetermined angle, so that the cover 5 is automatically rotated to close and placed in the closed state. will be returned to.

Example 3 (Fig. 10) In this example, a pinion 50 is integrally attached to the shaft end of the opening/closing central shaft 5a of the cover 5, and a cartridge 100
When the cartridge 100 is inserted and moved in the direction of arrow A to be installed in the main body of the image forming apparatus, the pinion 50 is moved from the middle of the insertion movement to the rack tooth 51 that is fixedly arranged in the direction of insertion and movement of the cartridge 100 on the side of the main body of the image forming apparatus. In the process of inserting and moving the cartridge 100, the pinion 50
moves counterclockwise on the rack teeth 51, and in conjunction with this, the cover 5 automatically opens and rotates.Finally, when the cartridge 100 is inserted and moved to the predetermined mounting position, the cover 5 is moved counterclockwise. It is fully opened and held in the open position shown in the second figure. Cartridge 100 in installed state
When the pinion 50 is moved in the direction B opposite to the input direction to take it out from the apparatus main body, the pinion 50 moves clockwise on the rack teeth 51 during the removal process, and The cover 5 automatically closes and rotates.

Example 4 (FIG. 11) In this example, rotation center shafts 5a are provided at both ends of the lower side of the cover 5, and the shafts 5a are connected to the cartridge housing 10, respectively.
The left and right end face plates are rotatably supported by bearings. In this case, contrary to the cases of Examples 1 to 3, the cover 5 is rotated counterclockwise around the shaft 5a to close the opening 11 and rotated clockwise. It is opened by this.

In this example, a gear G3 is integrally provided at the end of the shaft 5a, and a center shaft 33 for opening and closing the chain ring 32 is provided on the device opening/closing door 32 side.
A half-moon gear G4 is provided which rotates integrally with the door 32 around .

The door 32 is folded open as shown in FIG. 11(B), and the cartridge 100 with the cover 5 closed is mounted in the mounting portion in the main body of the apparatus.

Next, when the door 32 is closed, in the closing process, the half-moon gear G4 on the door 32 side rotates in a counterclockwise direction so that the gear G4 meshes with the gear G3 on the attached cartridge 100 side and rotates, thereby causing the gear G3 to rotate. When the cover 5 receives a clockwise rotational force, the cover 5 automatically opens and rotates clockwise about the shaft 5a. When the door 32 is sufficiently closed as shown in FIG. 11(A), the cover 5 is also sufficiently opened and rotated, so that the opening 11 of the installed cartridge 100 is held open.

From the closed state of the door shown in Fig. 11(A) to the closed state of the door 32 shown in Fig. 11CB
), during the opening process, the half-moon gear G4 rotates clockwise, causing the gear G3 to receive a counterclockwise rotational force, which causes the cover 5 to automatically rotate counterclockwise around the shaft 5a. It is closed and rotated.

〔Effect of the invention〕

By arranging the protective cover so that it can be freely rotated around one axis relative to the opening as described above, the cover opening/closing mechanism basically consists of only two parts: the central shaft for opening and closing the cover and its bearing. Since it can be easily configured, the number of parts and assembly man-hours are reduced, and problems in terms of manufacturing and cost are solved. Furthermore, since the range of opening and closing rotation of the cover is reduced, space constraints are alleviated and the cartridge can be made smaller. Since it is possible to open and close the cover with a small torque, it is also possible to simplify the mechanism for automatically opening and rotating the cover during or after installing the cartridge in the image forming apparatus main body. becomes.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the cartridge according to the embodiment with its protective cover closed, FIG.
The figure is an explanatory diagram of the waste toner conveyance path in the cleaning device.
Figure 4 is a perspective view of the cover hinge, Figures 5 and 6 are mechanical diagrams of the first example of the automatic cover opening/closing means, and Figure 7 is an enlarged view taken along line (7)-(7) in Figure 5. 8 is a perspective view of the rack and pinion portion, FIG. 9 is a mechanism diagram of the second example of the automatic cover opening/closing means, FIG. 10 is a mechanism diagram of the third example, and FIG.
Figures 1 (A) and (B) are mechanical diagrams of the fourth example, and Figure 12 (A).
) and (B) are a cross-sectional side view of an example of a conventional cartridge and a side view with the drum cover open. 1 is a photosensitive drum as an image carrier, 2 is a charging device, 3 is a developing device, 4 is a cleaning device, 5 is a protective cover, 5
11 is an opening, and 6 is an exposure window.

Claims (1)

[Claims] 1. An image forming apparatus in which a process cartridge containing at least an image bearing member is used by being attached to and removed from the apparatus main body, the process cartridge having a part of the surface of the image bearing member inside thereof exposed to the outside. It has a protective cover that can be freely rotated to open and close about one axis with respect to the cartridge opening facing the cartridge opening, and an interlocking mechanism that rotates the protective cover to open and close is provided on the central axis of opening and closing of the protective cover and on the side of the main body of the device. An image forming apparatus characterized by the following. 2. The interlocking mechanism operates in conjunction with the opening/closing operation of the opening/closing part of the device body to open/close the protective cover.
An image forming apparatus according to claim 1.