JP3432074B2 - Photoconductor holding device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for holding a photoconductor in an image forming apparatus, and more particularly, it suppresses rotation of the photoconductor during attachment / detachment and eliminates the difficulty of attachment / detachment of the photoconductor due to accompanying rotation. The present invention relates to a photoconductor holding device.

[0002]

2. Description of the Related Art An image forming apparatus using an electrophotographic system such as a copying machine and a facsimile uses a drum-shaped photoreceptor. Then, a charging device, a developing device, a transfer device, etc. are arranged around the photoconductor, and while the photoconductor is rotated, a document image is formed on the photoconductor to form an electrostatic latent image, which is developed. After forming a toner image by the device, it is transferred onto a sheet.

Further, in a color image forming apparatus, a plurality of units in which a charging device, a developing device and the like are arranged around a photoconductor are provided, and an image of an original document is color-separated to form an image for each color. A color image is formed by transferring them on the same sheet in an overlapping manner.

In order to rotate such a plurality of photoconductors, a conventional drive system drives a plurality of units with a single motor. Then, the photosensitive member is fixed by tightening the drum shaft (driving shaft) with a knob having a screw.

Therefore, when any one of the photoconductors is attached or detached, even if the screw of the knob is loosened, the photoconductor to be worked does not rotate with the load of the other image forming unit, and the photoconductor to be operated does not rotate. The work did not become difficult due to the surroundings.

However, when a plurality of photoconductors are rotated by one driving means, uneven rotation due to load fluctuations of other units is caused, which causes a slight deterioration in image quality. Due to the recent demand for image quality improvement, the influence of this rotation unevenness has become a problem.

Therefore, in order to solve this problem, a structure in which each photoconductor is driven by an independent motor has been adopted. With such a structure, it becomes possible to improve the image quality by cutting off the influence of the uneven rotation of other photoconductors.

[0008]

However, because of the above structure, when the knob is screwed or loosened when fixing the photoconductor to the drive shaft or removing it from the drive shaft, the drive shaft of the photoconductor is moved together with the knob. Also, there has been a problem that the photoconductor itself is rotated around, making it extremely difficult to attach and detach the photoconductor. The present invention solves this problem by
The purpose is to suppress rotation when the photoconductor is detached.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a photosensitive member holding device which detachably holds independently driven photosensitive members in an image forming apparatus main body. Rotation preventing means for preventing the rotation of the photoconductor when the device is attached to or detached from the apparatus, and the rotation suppressing means is provided on the main body of the image forming apparatus, and a stopper pin movable toward and away from the photoconductor; And a hole through which the stopper pin enters.

[0010]

A configuration in which a plurality of the holes are formed along the circumference of the side surface of the photoconductor, a configuration in which a guide slope for guiding the stopper pin into the hole is formed in the circumference, A configuration in which the stopper pin has an elastic play in the advancing / retreating direction, a configuration in which the advancing / retreating of the stopper pin has a push latch structure, and the stopper pin entering the hole of the photoconductor It is desirable to provide a detecting means for detecting, and to inhibit the operation of the image forming apparatus when the detecting means detects the rotation restrained state of the photoconductor.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. FIG. 1 shows a schematic structure of a photoreceptor holding device of the present invention. The photoconductor 1 has a front flange 2 on the left and right.
And a rear flange 3 are connected to each other, and are supported by a drive shaft 4 which penetrates the center. Both ends of the drive shaft 4 are fixed to a frame 7 and a face plate 8 as an image forming apparatus main body by bearing holders 5 and 6, and one end of the drive shaft 4 penetrates the bearing holder 5 and a driving means via a coupling 9 ( Motor) 10.

The rear flange 3 is fixed to the drive shaft 4 via a taper bush 11. The front flange 2 has a recess 2a, and the spring 12 is fitted between the recess 2a and the spring holder 12a. Bearing holder 5 for drive shaft 4
The screw 4a is engraved on the end of the side, and from here the knob 1
By screwing in 3, the load of the spring 12 is applied to the rear flange 3 via the front flange 2, and the rotation of the drive shaft 4 is transmitted to the photoconductor 1.

The front and rear frames 7, 7 of the photosensitive member 1 are integrally connected by a stay 14. The face plate 8 is the photoreceptor 1.
Which serves as a loading and unloading port for inserting the frame into the frame, and which is attached to the frame 7, but has a hole 8a.
Which has a positioning pin 1 formed on the stay 14
The face plate 8 is positioned by penetrating the plate 5.

The face plate 8 is provided with rotation suppressing means 17. The rotation suppressing means 17 includes a stopper pin 18 that can move back and forth toward the photoconductor 1, and the stopper pin 18
The button 19 provided on the rear side of the hook, the hook 20, and the hole 2b formed in the photoconductor 1.

FIG. 2 is a diagram showing the details of the hole 2b. A plurality of (six in this embodiment) holes 2b are formed on the side surface (front flange 2) of the photoconductor 1 along the circumference 2c. And between the adjacent holes 2b and 2b,
There is a guide slope 2d, and the hole 2b has exactly two guide slopes 2.
It is located at the valley bottom formed by d and 2d.
Even with this structure, the stopper pin 18 is
When it advances toward, the tip of the stopper pin 18 is guided by the guide slope 2d and easily enters the hole 2b.

FIG. 3 is a diagram showing a structure of a main part of the rotation suppressing means 17. The housing 21 is attached to the face plate 8, and the hollow cylindrical portion 19 a of the button 19 is installed in the housing 21.
Has been inserted through. A large-diameter spring 22 is fitted between the housing 21 and the button 19 and biased so as to separate the two. The housing 21 has a claw 21a at the tip thereof, and the claw 21a abuts against the tip of a locking groove 19b formed in the hollow cylindrical portion 19a to prevent the button 19 from falling off.

A stopper pin 18 is provided in the hollow cylindrical portion 19a.
Is slidably fitted. A small-diameter spring 23 is fitted between the rear end of the stopper pin 18 and the button 19 and is urged to separate the two. The stopper pin 18 has a groove 18a.
A claw 19c formed at the tip of the hollow cylindrical portion 19a is fitted in a to prevent the stopper pin 18 from falling off. The small-diameter spring 23 provides play (escape) when the stopper pin 18 does not enter the hole 2b of the photoconductor 1.
When the photoreceptor 1 is rotated by being screwed into the knob 13 and the stopper pin 18 is aligned with any of the holes 2b, the stopper pin 18 gives a force to enter the hole 2b.

When the photoconductor 1 is removed, first, the button 19 of the rotation suppressing means 17 is slightly rotated so that the projection 19d and the hook 20 do not interfere with each other, and then the push-in operation is performed to insert the stopper pin 18 into the hole 2b of the photoconductor. Intrude. When the positions of the stopper pin 18 and the hole 2b do not coincide with each other, if the knob 13 is held and the knob 13 is gripped and the photoconductor 1 is slightly rotated, one of the holes 2b comes to the front of the stopper pin 18. Then, the stopper pin 18 enters the hole 2b by the action of the small diameter spring 23. After that, if the button 19 is rotated in the reverse direction so that the protrusion 19d is locked to the hook 20, the backward movement of the button 19 is prevented, and thereafter, the photoconductor 1 is in a state in which the rotation is suppressed.

In this state, the knob 13 is rotated and removed, the bearing holder 5 is removed from the drive shaft 4, the face plate 8, the spring holder 12a and the spring 12 are removed, and the photoconductor 1 is extracted along the drive shaft 4. When mounting the photoconductor 1,
You can reverse this.

FIG. 4 is a diagram showing a second embodiment of the present invention.
This is an embodiment in which the operability of the button 19 is improved by preventing the button 19 from returning when the button 19 is pushed in, even if the pushed force is removed. In order to achieve such an object, in this embodiment, a push latch structure having a heart cam type groove is adopted.

FIG. 4 is a block diagram of the push latch, FIG. 5 is a view of the push latch groove viewed from above, FIG. 6 is a conceptual diagram showing a sectional structure of the push latch groove, and FIG. 7 is a push latch structure. It is a perspective view which shows the whole rotation suppression means provided.

As shown in FIG. 4, the housing 21 has a guide pin 25 made of a leaf spring, and its tip is urged so as to come into pressure contact with the hollow cylindrical portion 19a of the button 19. On the other hand, a push latch groove (hereinafter referred to as “groove”) 26 is formed in the hollow cylindrical portion 19a, and the guide pin 2
The tip of 5 is fitted in the push latch groove 26.
The hollow cylindrical portion in this embodiment has a square cross section.

FIG. 5 is a view showing the shape of the groove 26. As shown in the figure, the groove 26 has a heart shape as a whole,
It has four parts a, b, c, and d, each part is gentle, and a step is formed at the boundary thereof. FIG. 6 is a diagram conceptually showing a stepped state of each part a, b, c, d.

In FIG. 4, when the button 19 is pushed in,
The guide pin 25 moves in the a portion of the groove 26 and reaches the b portion at the position where the tip of the stopper pin 18 enters the hole 2b. When the stopper pin 18 enters the hole 2b and the rotation of the photoconductor 1 is blocked, the guide pin 25 reaches the portion c,
The button 19 does not move backward and is in a stable state.

When the photoconductor 1 is removed or attached, the button 19 is further pushed. Then, the guide pin 25 in the c section enters the d section. When the force applied to the button 19 in this state is removed, the guide pin 25 climbs up the slope of the d portion of the groove 26 shown in FIG. 6 and returns to the a portion, the stopper pin 18 comes out of the hole 2b, and the button 19 Returns to the initial state.

The guide pin 25 is blocked by the step, and
It can move only in the direction of b → c → d → a, and the operator can switch between the state in which the rotation of the photoconductor 1 is blocked and the state in which the photoconductor 1 is free to rotate, just by pushing the button 19. .

Further, in this embodiment, the shutter 28 is attached to the button 19 and the detecting means 29 is provided on the apparatus main body side. The detection means 29 is provided with a sensor 30 such as a photocoupler. When the button 19 is pushed in and the stopper pin 18 enters the hole 2b, the shutter 28 blocks the sensor 30 and exposes it to a control device (not shown). Informs that the body 1 is in a state where rotation is blocked.

Therefore, when the machine is powered on while the button 19 is being pushed in (the photosensitive member is being restrained from rotating) and a rotation operation is to be performed, a signal from the sensor 30 causes a message to appear on the operation panel. In addition to being configured to display a warning, it is possible to prevent the operation of the machine and prevent the failure of the machine.

[0030]

As described above, according to the present invention,
In a photoconductor holding device that detachably holds a photoconductor that is independently driven to rotate in an image forming apparatus main body, a configuration is provided in which a rotation suppressing unit that prevents rotation of the photoconductor when the photoconductor is attached to and detached from the device is provided. Therefore, it is possible to prevent the photoconductor from rotating around when the photoconductor is attached and detached from the main body of the image forming apparatus, and to easily attach and detach the photoconductor.

Further, the rotation suppressing means is composed of a stopper pin provided on the main body of the image forming apparatus and movable back and forth toward the photoconductor, and a hole formed in the photoconductor and into which the stopper pin enters. If so, the rotation of the photoconductor can be suppressed with a simple configuration.

If a plurality of the above holes are formed along the circumference,
It is possible to reduce the amount of rotation of the photoconductor when suppressing the rotation. By forming a guide slope on the circumference for guiding the stopper pin into the hole, even if the stopper pin and the hole do not coincide with each other, the hole can be easily reached by rotating the photoconductor. If the stopper pin has an elastic play in the advancing / retreating direction, the stopper pin and the hole can coincide with each other and the stopper pin can enter the hole at the same time.
It becomes easy to handle.

If the stopper pin has a push-latch structure for advancing and retreating, it is possible to alternately switch between a state in which the rotation of the photoconductor is blocked and a state in which the photoconductor is rotatable by pressing a button.

Detecting means for detecting that the stopper pin has entered the hole of the photoconductor is provided, and when the detecting means detects the rotation restrained state of the photoconductor, the operation of the image forming apparatus is prohibited. With the configuration, it is possible to prevent the image forming apparatus from being operated by mistake when the rotation of the photoconductor is suppressed.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a configuration of a photoreceptor holding device of the present invention.

FIG. 2A is a partially cutaway perspective view showing a hole of a photoconductor, and FIG. 2B is a sectional view of a circumferential portion of FIG.

FIG. 3 is a cross-sectional view showing a configuration of a main part of rotation suppressing means.

FIG. 4 is a cross-sectional view showing a main part of a rotation suppressing means according to another embodiment of the present invention.

FIG. 5 is a top view of a push latch groove.

FIG. 6 is a conceptual diagram illustrating a step difference in a push latch groove.

FIG. 7 is a perspective view showing a main part of rotation suppressing means.

[Explanation of symbols]

1 photoconductor 2b hole 2c circumference 2d guide slope 17 Rotation suppression means 18 Stopper pin 29 Detection means

Front page continuation (72) Inventor Toshio Shimazaki 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Co., Ltd. (56) Reference JP-A-7-199732 (JP, A) JP-A-55-32052 (JP, A) JP-A-8-6471 (JP, A) JP-A-6-329305 (JP, A) Actual development Sho 59-161166 (JP, U) (58) Fields investigated (Int. Cl. ⁷⁾ , DB name) G03G 21/16 G03G 21/00 350 G03G 21/00 370-540 G03G 15/00 550 F16H 49/00

Claims (6)

(57) [Claims] 1. A photoconductor holding device that detachably holds a photoconductor that is independently driven to rotate in an image forming apparatus main body, and prevents rotation of the photoconductor when the photoconductor is detached from the device. Means for providing the rotation suppressing means, the stopper pin being provided on the main body of the image forming apparatus and capable of moving forward and backward toward the photoconductor; and a hole formed in the photoconductor and into which the stopper pin enters. photoreceptor holding device shall be the features. 2. A photosensitive member holding device according to claim 1, wherein said hole is characterized in that the plurality bored along the circumference of the side surface of the photoconductor. 3. The photoconductor holding device according to claim 2 , wherein a guide slope is formed on the circumference for guiding the stopper pin into the hole. Wherein said stopper pin photoreceptor holding device according to any of claims 1 to 3, characterized in that it has an elastic play in the forward and backward direction. Wherein forward and backward in the stopper pin, claim 1, characterized in that has a push latch structure 4
7. The photoreceptor holding device according to any one of 1. 6. A detection means for detecting that the stopper pin has entered the hole of the photoconductor is provided, and when the detection means detects the rotation restrained state of the photoconductor, the operation of the image forming apparatus is started. photoreceptor holding device according to claim 1, characterized in that prohibited 5.