JPH0962073A - Image forming device - Google Patents

Abstract

(57) An object of the present invention is to provide an image forming apparatus capable of forming an appropriate image while reducing the occupied area. A supply roller 210 for supplying a toner for developing a latent image formed on the surface of a photoconductor 101 from a developing chamber 201 is provided, and a rotation axis of the supply roller is in a vertical direction or a direction inclined from the vertical direction. In the image forming apparatus to be arranged, the developing chamber 201 includes an ultrasonic oscillator 240a that vibrates and causes the toner in the developing chamber to fly and adhere to the supply roller 210.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a printer, a copying machine or a facsimile, which forms a toner image on a sheet. More specifically, the present invention relates to an image forming apparatus capable of reducing an occupied area during use, and mainly relates to a structure of a developing chamber thereof.

[0002]

2. Description of the Related Art Generally, since an image forming apparatus for forming a toner image on a sheet is designed to convey the sheet in a horizontal state, it has a drawback that it occupies a large area.

On the other hand, a conventional image forming apparatus for reducing the occupied area is disclosed in Japanese Patent Laid-Open No. 6-2.
The one described in Japanese Patent No. 02390 is known.

FIG. 5 is a perspective view showing the arrangement of each member inside the image forming apparatus described in the publication, and FIG. 6 is a top view of the apparatus.

As shown in these drawings, the apparatus has a sheet storage unit 1, a paper feed roller 2, a sheet conveying path 3, an image forming unit 4, a fixing device 5, a pair of paper discharge rollers 6 and the like, which are substantially upright. The sheet S is configured to be substantially upright and conveyed by being provided.

With such a configuration, the device can be set in a vertically long state, and the installation area can be reduced.

[0007]

SUMMARY OF THE INVENTION The above-mentioned JP-A-6-2
The publication No. 02390 does not disclose the structure around the developing chamber in the image forming unit 4.

On the other hand, in the structure of a generally known developing device, as shown in FIG. 7, for example, a toner T stored in a predetermined amount in a case 10 is supplied onto a developing roller 12 by a supply roller 11. The developing roller 12 supplies toner to the surface of the photoconductor (photosensitive drum in the figure) 13 to develop the latent image on the surface of the photoconductor to form a toner image. The toner image formed on the surface of the photoconductor 13 is transferred to the sheet S conveyed in the horizontal state. 1
4 is an agitator for stirring the toner in the case, 15
Is a blade that regulates the amount of toner on the developing roller 12.

However, in order to apply the structure of such a developing device to the image forming apparatus described in the above-mentioned Japanese Patent Laid-Open No. 6-202390, the standing state, that is, the rotation axis of the supply roller 11 or the like is in the vertical direction. With this arrangement, the toner T in the case 10 is biased to the bottom portion, the toner is not supplied to the upper portions of the supply roller 11 and the developing roller 12, and a toner image can be formed on the upper portion of the photoconductor 13. Disappear.

That is, in the prior art, if the image forming apparatus is arranged so that the rotation axis of the supply roller is in the vertical direction, there is a problem that an appropriate image cannot be formed.

An object of the present invention is to solve the above problems and to provide an image forming apparatus capable of forming an appropriate image while reducing the occupied area.

[0012]

In order to achieve the above object, an image forming apparatus according to a first aspect of the present invention is a supply roller for supplying a toner for developing a latent image formed on the surface of a photoconductor from a developing chamber. And an image forming apparatus in which the rotation axis of the supply roller is arranged in the vertical direction or in a direction inclined from the vertical direction, wherein the developing chamber vibrates the toner in the developing chamber to fly. It is characterized in that it is provided with an ultrasonic transducer attached to the supply roller.

An image forming apparatus according to a second aspect is the image forming apparatus according to the first aspect.
In the image forming apparatus described above, the ultrasonic transducer is a bottom surface or an inclination of the developing chamber when the image forming apparatus is arranged such that a rotation axis of the supply roller is oriented in a vertical direction or a direction inclined from the vertical direction. It is characterized by being arranged on the surface.

The image forming apparatus according to claim 3 is the image forming apparatus according to claim 1.
Alternatively, in the image forming apparatus according to the second aspect, the image forming apparatus may be arranged such that the rotation axis of the supply roller is oriented in the horizontal direction, and the ultrasonic transducer is such that the rotation axis of the supply roller is in the horizontal direction. The image forming apparatus is arranged on the bottom surface of the developing chamber when the image forming apparatus is arranged to face.

An image forming apparatus according to a fourth aspect of the present invention is the image forming apparatus according to the first, second, or third aspects, wherein the supply roller is made of a porous elastic body.

According to a fifth aspect of the present invention, in the image forming apparatus according to the first, second, third, or fourth aspect, the developing chamber is provided with a toner supply port. .

The image forming apparatus according to claim 6 is the image forming apparatus according to claim 5.
In the image forming apparatus described above, the replenishing port is provided at a position facing the ultrasonic transducer in the developing chamber.

The image forming apparatus according to claim 7 is the image forming apparatus according to claim 5.
Or the amount of toner replenished from the replenishing port is such that the toner is thinly deposited on the ultrasonic transducer disposed on the bottom surface when the operation of the apparatus is stopped. Is characterized in that.

An image forming apparatus according to an eighth aspect is the image forming apparatus according to the second, third, fourth, fifth, sixth or seventh aspect, wherein the bottom surface is an ultrasonic transducer arranged on the bottom surface. It is characterized in that it is inclined downwards.

An image forming apparatus according to a ninth aspect is the image forming apparatus according to the second, third, fourth, fifth, sixth, seventh, or eighth aspect in which ultrasonic waves are also applied to a wall surface of the developing chamber facing the supply roller. A vibrator is provided.

[0021]

According to the image forming apparatus of the present invention, the rotation axis of the supply roller for supplying the toner for developing the latent image formed on the surface of the photosensitive member from the developing chamber is vertical or inclined from the vertical direction. Since the sheet is arranged in the vertical direction, the sheet on which the image is formed can be conveyed in the vertical direction or in a state of being inclined from the vertical direction, and therefore, the occupied area can be reduced.

To the supply roller whose rotation axis is arranged in the vertical direction or in the direction inclined from the vertical direction, the toner in the developing chamber is supplied by the toner flying inside the developing chamber. Toner is attached from the upper end side to the lower end side of the roller.

Therefore, the toner is supplied from the upper end side to the lower end side of the supply roller, the toner image is not formed on the upper portion of the photoconductor, and a proper image is formed.

That is, according to the image forming apparatus of the first aspect, the occupied area can be reduced and at the same time,
A proper image can be formed.

According to the image forming apparatus of the second aspect, in the image forming apparatus of the first aspect, the ultrasonic transducer is oriented in a direction in which the rotation axis of the supply roller is vertical or inclined from the vertical direction. As described above, since the image forming apparatus is arranged on the bottom surface or the inclined surface of the developing chamber when the image forming apparatus is arranged, the toner in the developing chamber can effectively fly and adhere to the supply roller.

According to the image forming apparatus of the third aspect, in the image forming apparatus of the first or second aspect, the image forming apparatus can be arranged such that the rotation axis of the supply roller is oriented in the horizontal direction. Yes, since the ultrasonic transducer is arranged on the bottom surface of the developing chamber when the image forming apparatus is arranged so that the rotation axis of the supply roller is oriented in the horizontal direction, the ultrasonic transducer is arranged in the horizontal direction. However, it is possible to effectively fly the toner in the developing chamber and attach it to the supply roller.

According to the image forming apparatus of the fourth aspect, in the image forming apparatus of the first, second or third aspect, since the supply roller is made of a porous elastic body,
The flying toner adheres to the supply roller more efficiently.

According to the image forming apparatus of the fifth aspect, in the image forming apparatus of the first, second, third, or fourth aspect, the developing chamber is provided with a toner replenishing port, so that The toner consumed by adhering to the roller can be replenished through the replenishing port.

In the structure in which the toner in the developing chamber is made to fly by the ultrasonic vibrator, if a relatively large amount of toner is stored in the developing chamber as in the prior art shown in FIG. It is desirable to store a relatively small amount of toner in the developing chamber because the toner will not fly well. However, if the amount of toner in the developing chamber is low, it is difficult to form an image on a large number of sheets.

On the other hand, according to the image forming apparatus of the fifth aspect, the toner can be appropriately replenished through the replenishing port, so that the image can be formed on a large number of sheets.

According to the image forming apparatus of the sixth aspect, in the image forming apparatus of the fifth aspect, the replenishing port is provided at a position facing the ultrasonic transducer in the developing chamber. The toner replenished from the mouth will drop toward the ultrasonic transducer. Therefore, the toner is efficiently ejected by the ultrasonic vibrator.

According to the image forming apparatus of the seventh aspect, in the image forming apparatus of the fifth aspect or the sixth aspect, the amount of toner replenished from the replenishing port is set to the bottom surface when the operation of the apparatus is stopped. Since the amount is such that the toner is thinly deposited on the ultrasonic transducer arranged, it is possible to reliably fly the toner.

If the amount of toner supplied from the supply port is
If the amount of toner is such that the toner is relatively thickly deposited on the ultrasonic transducer disposed on the bottom surface when the operation of the apparatus is stopped, when the apparatus is activated again, There is a possibility that the toner that is deposited in a thick layer may interfere with the vibration of the ultrasonic vibrator and the flying of the toner, and the toner may not fly well.

On the other hand, according to the image forming apparatus of the seventh aspect, in the image forming apparatus of the fifth or sixth aspect, the amount of toner replenished from the replenishing port is determined when the operation of the apparatus is stopped. Since the amount of toner is such that the toner is thinly deposited on the ultrasonic vibrator disposed on the bottom surface, the toner deposited on the ultrasonic vibrator hinders vibration of the ultrasonic vibrator and flying of the toner. No longer,
Reliable flight of toner is obtained.

According to the image forming apparatus of the eighth aspect, in the image forming apparatus of the second, third, fourth, fifth, sixth or seventh aspect, the bottom surface is an ultrasonic vibration disposed on the bottom surface. Since it is inclined downward toward the child, the toner accumulated on the bottom surface and the toner that has fallen off will slide down toward the ultrasonic vibrator due to vibration. The toner that has slipped off is scattered by the ultrasonic vibrator, so that the toner can fly more efficiently.

According to the image forming apparatus of the ninth aspect, in the image forming apparatus of the second, third, fourth, fifth, sixth, seventh or eighth aspect, the wall surface of the developing chamber facing the supply roller is also provided. Since the ultrasonic vibrator is provided, the toner flying in the developing chamber acts on the supply roller by the vibration of the ultrasonic vibrator, and adheres to the supply roller more efficiently.

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan sectional view showing an image forming unit which is a main part of an embodiment of an image forming apparatus according to the present invention, FIG. 2 is a partially omitted sectional view taken along line II-II in FIG. 1, and FIG. 3 is a partially omitted sectional view taken along line III-III in FIG.

The image forming unit U can be applied to, for example, the image forming unit 4 in the image forming apparatus shown in FIG.

As shown in FIG. 1, the image forming unit U
Is a photosensitive drum 101, which is a photoconductor, and a charging roller 10.
2 and the developing device 200 which is a characteristic part of this embodiment,
The cleaning blade 103 and the cleaning blade 103 are incorporated into the case 110 to form a single unit. The axes of the rotating bodies in the image forming unit U are all oriented in the vertical direction. That is, as shown in FIGS. 2 and 3, the image forming unit U is in a vertically placed state.

First, the entire unit will be described.
Next, the developing device 200, which is a characteristic part, will be described in detail.

The photosensitive drum 101 is constructed by forming a photosensitive layer made of an organic photosensitive body on a conductive base made of an aluminum drum, and is rotatably supported by the case 110.
It is rotationally driven in the direction of arrow a by a drive mechanism (not shown). Note that the photosensitive member may be configured by a photosensitive belt or the like other than the photosensitive drum.

The charging roller 102 is pressed against the photosensitive drum 101 by a pressing mechanism (not shown), and charges the photosensitive drum 101 while following the photosensitive drum 101. A bias voltage is applied to the charging roller 102.

The charged photosensitive drum 101 is scanned by a laser beam LB emitted from an optical unit (not shown), whereby a latent image is formed on the surface of the photosensitive drum 101.

The case 110 has an upper wall 111 (see FIG. 2), a bottom wall 112, and a peripheral wall 113, and a slit 114 for beam scanning is formed in the peripheral wall 113.

The developing device 200 includes the case 110,
The developing chamber 201 formed to be long in the vertical direction, and the upper wall 111 and the bottom wall 11 in a state of facing the developing chamber 201.
2, a supply roller 210 that is rotatably provided, a developing roller 220 that is also rotatably provided on the upper wall 111 and the bottom wall 112, and a regulating blade 230 that is in contact with the peripheral surface of the developing roller 220. And ultrasonic transducers 240a and 240b provided on the inner wall surface of the developing chamber 201. The supply roller 210 and the developing roller 220 are
The drive mechanism interlocking with the drive mechanism of the photosensitive drum 101 is rotationally driven in the direction of the arrow in FIG. The regulation blade 230 is made of an elastic body such as a stainless steel plate,
It is attached to the case 110 by the attachment member 231.

A relatively small amount of toner is stored in the developing chamber 201, and when the ultrasonic vibrators 240a and 240b are operated, the toner is ejected by the vibration. The flying toner fills the developing chamber 201, and the supply roller 2
It adheres to the surface of 10. The supply roller 210 coats the surface of the developing roller 220 with the toner attached to the surface thereof. The toner coated on the surface of the developing roller 220 is brought into sliding contact with the regulation blade 230 to be thinned and frictionally charged. A bias voltage is applied to the developing roller 220, the thinned toner is conveyed to the photosensitive drum 101, and the photosensitive drum 101 is nipped at the nip portion formed by the pressure contact portion between the developing roller 220 and the photosensitive drum 101. The latent image is reversely developed.
As a result, the latent image on the surface of the photosensitive drum 101 is developed and a toner image is formed.

The toner image formed on the surface of the photosensitive drum 101 is transferred to the sheet S which is conveyed by being sandwiched between the transfer roller 106 to which a bias voltage having a polarity opposite to that of the toner image is applied and the photosensitive drum 101. It

The cleaning blade 103 is attached to the mounting member 1.
It is attached to the case 110 by 03a. One end edge 103b of the cleaning blade 103 is in contact with the peripheral surface of the photosensitive drum 101, and the toner image is transferred to the sheet S.
The residual toner adhering to the surface of the photosensitive drum 101 after being transferred to is scraped off.

The photosensitive drum 101, which has been cleaned by scraping off the residual toner, returns to the above-mentioned image forming process.

In FIG. 1, 107 is a film seal which is in sliding contact with the photosensitive drum 101, and 108 is a film seal which is in sliding contact with the developing roller 220.

Next, the developing device 200 will be described in detail with reference to FIGS. 1 to 3.

The developing chamber 201 includes a case 110 and partition walls 115, 115 integrally formed in the case 110.
And the supply roller 210 arranged between the partition walls 115.

The supply roller 210 is made of a material to which toner easily adheres, for example, a porous elastic body. In this embodiment, it is made of a sponge.

As shown in FIGS. 1 and 2, the ultrasonic vibrator 240a is attached to the bottom surface 201a of the developing chamber 201 when the image forming apparatus is arranged so that the rotation axis of the supply roller 210 is oriented in the vertical direction. Has been.

The image forming unit U of this embodiment is
It is also possible to arrange and use the supply roller 210 such that the rotation axis of the supply roller 210 is oriented in the horizontal direction (in a state in which FIG. 1 is viewed from the front). Development chamber 20 when arranged as
A plurality (two in the figure) are attached to the bottom surface 201b of one.

These ultrasonic transducers 240a and 240b
Is for vibrating and flying toner (not shown) in the developing chamber 201 so that the toner adheres to the supply roller 201. The toner is driven by a drive circuit (not shown) and vibrates.

In the developing chamber 201, a toner supply port 250
a, 250b, 250b are provided. Supply port 25
0a is provided at a position facing the ultrasonic oscillator 240a, and the supply ports 250b and 250b are provided at the ultrasonic oscillator 24a.
0b and 240b are provided at opposite positions.

A toner supply path 251 is provided in the supply ports 250a and 250b. The supply path 251 is formed in a tubular shape that is integral with the case 110, and communicates with all the supply ports 250a and 250b.

Inside the replenishing path 251, a toner conveying means 252 is provided. In this embodiment, the conveying means 252 is composed of a screw, but it may be composed of a coil spring. The transport unit 252 is rotationally driven by a drive mechanism that is interlocked with the drive mechanism of the photosensitive drum 101. A toner tank (not shown) is provided at an appropriate position on the supply path 251, and toner is supplied from the toner tank to the supply path 251. The supplied toner is conveyed in the replenishing path 251 by the conveying means 252 in the order of arrows T1, T2 and T3, and each replenishing port 250 is supplied.
a, 250b to the developing chamber 201. When the device is used in a vertically installed state (the rotation axis of the supply roller 210 is oriented in the vertical direction), the supply port 250 is used.
The toner that has flowed out of the a will drop toward the ultrasonic vibrator 240a, and will be replenished when the device is used in a state in which the device is placed horizontally (the rotation axis of the supply roller 210 is oriented in the horizontal direction). The toner flowing out from the opening 250b falls toward the ultrasonic vibrator 240b.

The amount of toner replenished into the developing chamber 201 through the replenishing port is determined by the bottom surface (20) when the operation of the apparatus is stopped.
1a or 201b) the ultrasonic transducer 2
The amount is set such that the toner is thinly deposited on 40a or 240b.

Next, the operation of the developing device 200 will be described. It should be noted that the basic operation is the same whether the device is in the vertical position or in the horizontal position, but there are some differences, so the operation in the vertical position will be described first, and then The operation in the horizontal state will be described.

<When the apparatus is vertically installed> (i) In the state where the operation of the apparatus is stopped, the toner existing in the developing chamber 201 remains on the bottom surface 201a and the ultrasonic vibrator 240a. It is in a state of being thinly deposited (to a thickness of about 1 mm).

(Ii) When the device operates, the photosensitive drum 1
01, the supply roller 210, and the developing roller 220 rotate, or at the same time as or before the ultrasonic vibrators 240a and 240b are driven, the screw 252 rotates. When the ultrasonic vibrators 240a and 240b are driven, the toner accumulated on the ultrasonic vibrator 240a is vibrated and flies, and the developing chamber 201 is filled with the toner. As a result, the toner adheres to the surface of the supply roller 210. The toner is supplied by the supply roller 21.
0 is attached from one end side to the other end side almost evenly.

When the screw 252 rotates, the toner is conveyed in the order of arrows T1, T2 and T3 and flows out from the replenishing ports 250a and 250b into the developing chamber 201. The toner flowing out from the replenishing port 250a is transferred to the ultrasonic vibrator 240.
Since it falls toward a, most of it will be scattered in the process, and it will fly efficiently. The toner flowing out from the replenishing port 250b is partly scattered by the action of the ultrasonic vibrators 240a and 240b, but the remaining part reaches the bottom surface 201a. Therefore,
In order to obtain a more efficient flying state of toner, FIG.
It is desirable that the bottom surface 201a be a downward slope facing the ultrasonic transducer 240a, as indicated by a virtual line 201a '. With such a configuration, the toner (and the accumulated toner) that has fallen on the bottom surface 201a 'slides down toward the ultrasonic oscillator 240a due to vibration and is scattered by the ultrasonic oscillator 240a, so that the efficiency is further improved. The toner will fly well.

Further, in order to make the toner filled in the developing chamber 201 adhere to the supply roller 210 more efficiently,
It is desirable to provide an appropriate number of ultrasonic transducers 240c on the side surface 201c facing the supply roller 210. With such a configuration, the flying toner may cause the ultrasonic transducer 2 to
The vibration of 40c acts so as to hit the supply roller 210, and efficiently adheres to the supply roller.

(Iii) When the sheet is fed to the image forming apparatus and the photosensitive drum 101, the supply roller 210, and the developing roller 220 rotate at a predetermined timing with respect to the conveyed sheet, as described above. Toner is supplied from the inside of the developing chamber 201 to the surface of the developing roller 220 by the supply roller 210, and the latent image on the photosensitive drum 101 is reversely developed. The toner image formed on the surface of the photosensitive drum 101 is transferred to the sheet S, and then passes through a fixing device (not shown) to be fixed on the sheet S.

By supplying the toner to the surface of the developing roller 220 via the supplying roller 210, the developing chamber 20
The toner in 1 is consumed, but the supply ports 250a, 250
Since the toner is replenished from b as described above, it is possible to continuously form images on a plurality of sheets.

Therefore, the amount of toner replenished into the developing chamber 201 through the replenishment ports 250a and 250b is such that an image can be continuously formed on a plurality of sheets, and the operation of the apparatus is When stopped, bottom surface 201a
The amount is set to such a degree that the toner is thinly deposited on the ultrasonic vibrator 240a arranged at.

(Iv) When the operation of the apparatus is stopped after the predetermined image formation is completed, the operations of the ultrasonic transducers 240a and 240b are also stopped. Therefore, the toner flying in the developing chamber 201 gradually falls, is thinly deposited on the bottom surface 201a, and returns to the state of (i) described above.

The above operations (i) to (iv) can be obtained even when the axis of the rotating body in the unit U is oriented in the direction V1 which is inclined by the angle θ from the vertical direction V shown in FIG. 3, for example. . In this case, the ultrasonic transducer 240a,
240b is arranged on the inclined surface of the developing chamber 201 when the image forming apparatus is arranged so that the rotation axis of the supply roller 210 is inclined from the vertical direction. In this case, since the toner is deposited on one of the inclined surfaces 201a ′ and 201a ′ shown by imaginary lines in FIG. 3, it is also possible to provide an ultrasonic transducer on these inclined surfaces. desirable.

<When the apparatus is in a horizontal position> (i) When the operation of the apparatus is stopped, the toner existing in the developing chamber 201 is generated by the ultrasonic vibrator 240b.
It is in a state of being thinly deposited on the top.

(Ii) When the device is activated, the photosensitive drum 1
01, the supply roller 210, and the developing roller 220 rotate, or at the same time as or before the ultrasonic vibrators 240a and 240b are driven, the screw 252 rotates. When the ultrasonic vibrators 240a and 240b are driven, the toner accumulated on the ultrasonic vibrator 240b is vibrated and flies, and the developing chamber 201 is filled with the toner. As a result, the toner adheres to the surface of the supply roller 210. The toner is supplied by the supply roller 21.
0 is attached from one end side to the other end side almost evenly.

When the screw 252 rotates, the toner is conveyed in the order of arrows T1, T2 and T3, and the replenishment ports 250 are provided.
a, 250b to the developing chamber 201. Supply port 25
Since the toner flowing out from 0b drops toward the ultrasonic vibrator 240b, most of the toner will be scattered in the process, and the toner will fly efficiently. Supply port 25
Part of the toner flowing out from the 0a is the ultrasonic transducer 2
Although it will be scattered by the action of 40a and 240b, the remaining part reaches the bottom surface 201b. Therefore, in order to obtain a more efficient toner flying state, it is necessary to use
It is desirable that the bottom surface 201b is a downward slope facing the ultrasonic transducer 240b, as indicated by a virtual line 201b '. With such a configuration, the toner (and the accumulated toner) that has fallen on the bottom surface 201b ′ slides down toward the ultrasonic vibrator 240b due to vibration and is scattered by the ultrasonic vibrator 240b, so that the efficiency is further improved. The toner will fly well.

A side surface 201c facing the supply roller 210
As described above, it is desirable to provide an appropriate number of ultrasonic transducers 240c.

(Iii) A sheet is fed to the image forming apparatus, and when the photosensitive drum 101, the supply roller 210, and the developing roller 220 rotate at a predetermined timing with respect to the conveyed sheet, as described above. Toner is supplied from the inside of the developing chamber 201 to the surface of the developing roller 220 by the supply roller 210, and the latent image on the photosensitive drum 101 is reversely developed. The toner image formed on the surface of the photosensitive drum 101 is transferred to the sheet S, and then passes through a fixing device (not shown) to be fixed on the sheet S.

By supplying the toner to the surface of the developing roller 220 via the supplying roller 210, the developing chamber 20
The toner in 1 is consumed, but the supply ports 250a, 250
Since the toner is replenished from b as described above, it is possible to continuously form images on a plurality of sheets.

Therefore, the amount of toner replenished into the developing chamber 201 through the replenishment ports 250a and 250b is such that images can be continuously formed on a plurality of sheets, and the operation of the apparatus is When stopped, bottom surface 201b
The amount is set to such a degree that the toner is thinly deposited on the ultrasonic transducer 240b arranged at.

Here, provisionally, supply ports 250a and 250b are provided.
If the rotation speed of the screw 252 is the same in the case where the apparatus is in the vertical installation state and the case where the apparatus is in the horizontal installation state, There is a problem that the amount of toner flowing into the developing chamber 201 is different from that in a certain case.

This is because the amount of toner flowing out from the replenishing port located on the upper surface of the developing chamber 201 is different from that from the replenishing port located on the side surface. In this embodiment, the upper surface in the case of vertical placement. This is because there is one replenishment port 250a located on the upper side and there are two replenishment ports 250b located on the upper surface in the case of being placed horizontally. More specifically, in the vertical state as shown in FIG. 3, the outflow amount from the replenishment port 250a located on the upper surface is the outflow amount from the replenishment port 250b (one) located on the side face. Compared to many. This is because the supply port 250a located on the upper surface faces the free fall direction of the toner, whereas the supply port 250b located on the side face faces in the direction orthogonal to the free fall direction of the toner. For the same reason, in the horizontally placed state (a state where FIG. 1 is viewed from the front), the outflow amount from the replenishment port 250b (one) located on the upper surface is
The amount is larger than the outflow amount from the supply port 250a located on the side surface.

In this embodiment, the number of the replenishing ports 250a is one, whereas the number of the replenishing ports 250b is two, so that the replenishing port 2 is temporarily provided.
If the diameters of 50a and 250b are the same and the number of rotations of the screw 252 is the same in the case where the device is in the vertical installation state and in the horizontal installation state, the case where the device is in the vertical installation state In the case of being placed, the developing chamber 2
Therefore, there arises a problem that the amount of toner flowing into the inside of 01 becomes different.

Such a problem is that the number of the supply ports 250a is two, and the diameter of the supply ports 250b is the same.
The number of rotations of the screw 252 is made smaller (for example, 1/2) than that when vertically installed (for example, 1/2), and the like. It can be solved by taking it.

In this embodiment, a detecting means is provided in the image forming apparatus to detect whether the apparatus is in the vertical installation state or the horizontal installation state. If the apparatus is in the horizontal installation state,
By halving the number of rotations of the screw 252, the amount of toner flowing into the developing chamber 201 becomes substantially the same regardless of whether the apparatus is in the vertical position or the horizontal position. There is. As the detecting means, a known one can be adopted. For example, the detection means 260 as shown in FIG. 4 can operate. The detecting means 260 includes a base 261, a swinging member 262 swingably supported by the base, and a photo sensor 263 for detecting the state of the swinging member.
The swing member 262 swings by its own weight when the installation posture of the image forming apparatus is changed, and the photo sensor 263 is turned on when its detection light is blocked by the swing member. It has become. The photo sensor 263 is connected to a control unit (not shown) that controls the operation of the entire image forming apparatus. Therefore, for example, the photo sensor 26
When 3 is OFF, it can be detected that it is in the vertical position, and when it is ON, it can be detected that it is in the horizontal position. The detecting means 260 is configured as one unit, and can be attached to a proper place in the image forming apparatus.

(Iv) When the predetermined image formation is completed and the operation of the apparatus is stopped, the driving of the ultrasonic transducers 240a and 240b is also stopped. Therefore, the toner flying in the developing chamber 201 gradually drops, and the bottom surface 201b
It is thinly deposited on the top and returns to the state of (i) described above.

According to the image forming apparatus having the unit U as described above, the following operational effects can be obtained.

(A) The rotation axis of the supply roller 210 for supplying the toner for developing the latent image formed on the surface of the photosensitive drum 101 from the developing chamber 201 is in the vertical direction V or the direction V1 inclined from the vertical direction. Since they are arranged, the sheet S on which an image is formed can be conveyed in the vertical direction or in a state of being inclined from the vertical direction, and therefore, the occupied area can be reduced.

For the supply roller 210 whose rotation axis is arranged in the vertical direction or in the direction inclined from the vertical direction, the ultrasonic vibrator 24 provided in the developing chamber 201 is provided.
When the toner in the same room flies due to 0a, etc.,
The toner is evenly attached from the upper end side to the lower end side of the supply roller 210.

Therefore, the toner is almost evenly supplied from the upper end side to the lower end side of the supply roller 210, and the toner image is not formed on the upper portion of the photosensitive drum 101, and a proper image is formed. Will be done.

That is, according to this image forming apparatus, the occupied area can be reduced, and at the same time, an appropriate image can be formed.

(B) The ultrasonic transducer 240a is a bottom surface or an inclined surface of the developing chamber 201 when the image forming apparatus is arranged so that the rotation axis of the supply roller 210 is oriented in the vertical direction or a direction inclined from the vertical direction. Since it is arranged at 201a, the toner in the developing chamber 201 can be effectively ejected and adhered to the supply roller 201.

(C) This image forming apparatus has the supply roller 2
The ultrasonic transducer 240b can be arranged so that the rotation axis of the supply roller 210 is oriented in the horizontal direction. Since it is arranged on the bottom surface 201b, the toner in the developing chamber 201 can be effectively ejected and adhered to the supply roller 210 even when arranged in the horizontal direction.

(D) Since the supply roller 210 is made of a porous elastic body, the flying toner adheres to the supply roller 210 more efficiently.

(E) Since the developing chamber 201 is provided with toner replenishing ports 250a and 250b, the toner consumed by adhering to the supply roller 210 can be replenished through the replenishing ports 250a and 250b. it can.

In the structure in which the toner in the developing chamber 201 is caused to fly by the ultrasonic vibrators 240a and 240b,
For example, if a relatively large amount of toner is stored in the developing chamber as in the prior art shown in FIG. 7, the ultrasonic transducer 24
It is desirable to store a relatively small amount of toner in the developing chamber 201, because the toner will not fly properly due to the toner particles 0a and 240b. However, if the amount of toner in the developing chamber 201 is low, there arises a problem that images cannot be formed on a large number of sheets.

On the other hand, according to this image forming apparatus,
Since toner can be appropriately supplied through the supply ports 250a and 250b, images can be formed on a large number of sheets S.

(F) Since the replenishment ports 250a and 250b are provided at the positions facing the ultrasonic transducers 240a and 240b in the developing chamber 201, the toner replenished from the replenishment ports is directed toward the ultrasonic transducers. It will fall. Therefore, the toner is efficiently ejected by the ultrasonic vibrator.

(G) The amount of toner replenished from the replenishing ports 250a and 250b is such that the toner is thinly deposited on the ultrasonic vibrator 240a or 250b disposed on the bottom surface when the operation of the apparatus is stopped. Since it is the amount, reliable flight of the toner can be obtained.

If the amount of toner replenished from the replenishing ports 250a and 250b is such that the toner is relatively thickly deposited on the ultrasonic vibrator 240a or 250b arranged on the bottom surface when the operation of the apparatus is stopped. When the apparatus is operated again, the toner thickly deposited on the ultrasonic vibrator 240a or 250b will be removed by the ultrasonic vibrator 2 when the apparatus is operated again.
The vibration of 40a or 250b and the flying of the toner may be hindered, and the toner may not fly well.

On the other hand, according to this image forming apparatus,
The amount of toner replenished from the replenishment ports 250a and 250b is
When the operation of the apparatus is stopped, the amount of toner is thinly deposited on the ultrasonic vibrator 240a or 250b arranged on the bottom surface. Therefore, the amount of toner deposited on the ultrasonic vibrator 240a or 250b is extremely small. No longer obstructing the vibration of the sound wave oscillator and the flying of the toner,
Reliable flight of toner is obtained.

(H) The bottom surfaces 201a and / or 201b of the developing chamber 201 are inclined surfaces 201a 'and 201b' which are inclined downward toward the ultrasonic transducer 240a or 240b arranged on the bottom surface. In this case, the toner that has accumulated on the bottom surface and the toner that has fallen off will slide down toward the ultrasonic vibrator due to vibration, and the toner that has slipped off will be scattered by the ultrasonic vibrator, so the toner will be even more efficient. Will fly.

(I) Supply roller 2 in developing chamber 201
Ultrasonic transducer 240c on the side surface 201c facing 10
In the case where the above is provided, the toner flying in the developing chamber 201 acts so as to collide with the supply roller 210 by the vibration of the ultrasonic vibrator 240c, and adheres to the supply roller 210 more efficiently.

That is, according to this embodiment, a proper image can be formed regardless of whether the image forming apparatus is arranged vertically or horizontally or diagonally.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be appropriately made within the scope of the gist of the present invention.

[0104]

According to the image forming apparatus of the present invention, the occupied area can be reduced and at the same time an appropriate image can be formed.

[0105]

[Brief description of drawings]

FIG. 1 is a plan sectional view showing an image forming unit which is a main part of an embodiment of an image forming apparatus according to the present invention.

FIG. 2 is a partially omitted II-II sectional view in FIG.

FIG. 3 is a partially omitted sectional view taken along line III-III in FIG.

FIG. 4 is a perspective view showing an example of detection means.

FIG. 5 is an explanatory diagram of a conventional technique.

FIG. 6 is an explanatory diagram of a conventional technique.

FIG. 7 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 S sheet 101 photosensitive drum 200 developing device 201 developing chamber 210 supply roller 220 developing roller 240a ultrasonic vibrator 240b ultrasonic vibrator 250a replenishing port 250b replenishing port

Claims (9)

[Claims] 1. A supply roller for supplying a toner for developing a latent image formed on the surface of a photoconductor from a developing chamber, wherein the rotation axis of the supply roller is arranged in a vertical direction or a direction inclined from the vertical direction. The image forming apparatus according to claim 1, wherein the developing chamber includes an ultrasonic vibrator that vibrates and causes the toner in the developing chamber to fly and adhere to the supply roller. . 2. The ultrasonic vibrator is provided on a bottom surface or an inclined surface of the developing chamber when the image forming apparatus is arranged so that a rotation axis of the supply roller is oriented in a vertical direction or a direction inclined from the vertical direction. The image forming apparatus according to claim 1, wherein the image forming apparatus is arranged. 3. The image forming apparatus can be arranged so that the rotation axis of the supply roller is oriented in the horizontal direction, and the ultrasonic transducer is arranged so that the rotation axis of the supply roller is oriented in the horizontal direction. The image forming apparatus according to claim 1, wherein the image forming apparatus is arranged on a bottom surface of the developing chamber when the image forming apparatus is arranged. 4. The supply roller is composed of a porous elastic body.
The image forming apparatus as described in the above. 5. The image forming apparatus according to claim 1, wherein the developing chamber is provided with a toner supply port. 6. The image forming apparatus according to claim 5, wherein the replenishing port is provided at a position facing the ultrasonic transducer in the developing chamber. 7. The amount of toner replenished from the replenishing port is
7. The image forming apparatus according to claim 5, wherein the amount is such that the toner is thinly deposited on the ultrasonic transducer disposed on the bottom surface when the operation of the apparatus is stopped. 8. The method according to claim 2, wherein the bottom surface is inclined downward toward the ultrasonic transducer arranged on the bottom surface. Image forming apparatus. 9. The image according to claim 2, wherein an ultrasonic transducer is also provided on a wall surface of the developing chamber facing the supply roller. Forming equipment.