JPH04366980A - Image forming device - Google Patents

Abstract

PURPOSE:To regulate the vertical movement when a developing device is attached/detached to/from the main body by a simple method and to prevent the contact of a developing sleeve with a photosensitive body. CONSTITUTION:The developing device 1 is supported on a guide rail 3 provided with a supporting face 31 and a guiding 32 which are attached to a main body frame 12 with the flat surface 12a of a flange part 12. The developing device 1 is positioned in such a manner that the developing sleeve 11 faces the photosensitive body 4 with a fixed fine gap. A bias terminal 13 is attached to the fixed shaft of the developing sleeve 11. Its lead wire 14 is led from the front to the back and connected to main body side in the back to be biased. The lead wire 14 is covered with a bias terminal cover 16. Its upper face 16a is made to face the guide surface 32 of the guide rail 3 with the fine gap delta by which they do not contact with each other. Therefore, the vertical movement of the developing device is prevented at the times of its attachment/detachment, a cover member can also be used as the member for regulating the vertical movement, and the reduction in the cost can be achieved by means of the simple structure.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a guide technique for attaching and detaching a developing device to an image forming apparatus such as a copying machine and a printer, which is equipped with a developing device that is detachable from the main body.

0002

2. Description of the Related Art In conventional image forming devices such as copying machines, service personnel perform periodic maintenance, and users replace the developing device for monochrome copies with the developing device containing color toner. Since color copies are often made, it is essential that the image forming apparatus be able to be inserted into and removed from the main body of the image forming apparatus. Various methods have been used for this insertion and removal, one of which is the guide rail method which is low in cost and has a simple structure.

[0003] As a guide rail type copying machine, when the developing device is inserted into and removed from the main body of the image forming apparatus, the developing device is slid toward the photoreceptor side during insertion to prevent contact with the photoreceptor. It has been proposed (Japanese Patent Laid-Open No. 1986-
201371, 63-191352).

FIG. 7 shows the arrangement of a photoreceptor and a developing device in an image forming apparatus of this type. There is a guide rail 3' on the copying machine main body side, and the developing device 1' is inserted from the front side to the back side along the guide rail 3'. In this case, guide rail 3'
The supported portion 12' of the developing device has a structure as shown in FIGS. 8(a), (b) and 9(a), (b),
When the supported part 12' is inserted into the guide rail 3',
As shown in FIGS. 0 and 11, the developing device is set at a predetermined position with respect to the photoreceptor by being aligned in the direction of the photoreceptor. Reference numeral 5' indicates a stopper.

[0005] Also, in this developing device, FIGS. 7, 12 and 1
As shown in Fig. 3, a terminal 13' is attached to the shaft 11'a on the non-rotating front side of the developing sleeve 11', and a lead wire is led to the rear of the copying machine body where the power source is located, thereby providing a stable bias. is adopted. Then, cover member 16' is installed to prevent the lead wire from entering the user's view.
covered with

However, in the conventional developing device as described above, the height of the cover member 16' is low and the distance A between the top surface of the cover member 16' and the bottom surface of the guide rail 3' is large. When inserting and removing the developing device from the guide rail 3', the vertical position is not regulated and there is a large amount of play, and the photoconductor and the developing sleeve tend to come into contact with each other due to the vertical movement of the sleeve, so care must be taken when inserting and removing the developing device. It was inconvenient to operate.

In this case, it is conceivable to provide the guide rail itself with a member for regulating the vertical movement of the developing device, but this would complicate the structure of the guide rail and increase costs. Particularly, as shown in FIG. 7, when the guide rail is integrally formed from a sheet metal, providing a member for restricting upward movement of the supported portion 12' complicates the structure and is not preferable in terms of processing.

[0008]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems in the prior art and regulates the vertical movement of the developing device when it is attached to and detached from the main body using a simple method without causing an increase in cost.
It is an object of the present invention to provide an image forming apparatus with good operability without fear of a developing sleeve coming into contact with a photoreceptor.

[0009]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the invention of claim 1 provides an image forming apparatus comprising a photoreceptor, a developing device, and a support member for supporting the developing device. The photoreceptor extends from one side of the image forming apparatus to the other side, and the developing device includes a supported portion that is a portion on which the developing device is supported. a developing sleeve that faces the surface of the photoreceptor with a gap therebetween; an electric wire that is led from the one side to the other side and applies a bias to the developing sleeve; and a surface that covers the electric wire is opposite to the surface that covers the electric wire. a cover member whose side surface faces the flat surface of the supported part at a predetermined distance, and is removable from one side to the other side or from the other side to one side, and the supporting member In the image forming apparatus, the image forming apparatus includes a plate-shaped portion fixed to the forming apparatus main body and having a flat surface supporting the flat surface of the supported portion and an opposite flat surface parallel to the flat surface. In addition to the above, the invention of claim 2 is characterized in that the opposite surface and the opposite flat surface of the support member face each other with a gap sufficient to allow smooth attachment and detachment of the developing device. The invention of claim 3 is characterized in that the other end of the opposite surface of the cover member has an inclined surface inclined in a direction away from the support member, In addition to the feature, the starting point of the inclined surface reaches one side end of the supported portion before the other side plate of the developing device reaches the image area of the photoreceptor when the developing device is mounted. The invention of claim 4 is characterized in that, in addition to the features of the invention of claims 1 to 3, the supported portion is a surface opposite to the flat surface to be supported, which is both ends of the one side and the other side. The support member is provided with a protrusion that protrudes to the side, and when the protrusion hits a position at the end of the one side that abuts the protrusion when the developing device is attached, the support member retreats from the mounting direction and is retracted from the protrusion when pulled out. It is characterized by having a stop member that stops the stop member when it comes into contact with the stop member.

0010

According to the invention as claimed in claim 1, the opposite surface of the cover member and the opposite flat surface of the support member are disposed facing each other with a gap sufficient to allow smooth attachment and detachment of the developing device. The plate-shaped portion of the support member is sandwiched between the opposite surface of the cover member and the flat surface of the supported portion, and vertical movement of the developing device is prevented during attachment and detachment.

According to the invention of claim 2, in addition to the above,
Since the other end of the opposite side surface of the cover member is formed into an inclined surface that is inclined in a direction away from the support member, the cover member opens when being attached, making it easy to insert the cover member into the support member.

According to the invention of claim 3, in addition to the effect of the invention of claim 2, when the developing device is mounted, the other side plate of the developing device is aligned with the image area of the photoreceptor. Since the side plate reaches one side edge of the supported part before reaching the image plane, the image surface of the photoreceptor will not be damaged even if it moves up and down during installation, and the slope ends when the side plate reaches the image surface. There will be no rattling and will not damage the image surface.

According to the invention of claim 4, claims 1 to 3
In addition to the effects of the invention, there are protrusions that protrude on the opposite side of the flat surface to be supported at both ends of the supported part, and a projection that is located at the end of one side of the support member and is A stop member is provided that retreats from the installation direction when the protrusion hits the protrusion when the device is attached, and stops the developing device when it comes into contact with the protrusion when being pulled out, thereby preventing the developing device from slipping out and falling when being pulled out. be done. In this case, it becomes difficult to regulate the vertical position of the supported part, but this is made possible by the cover member.

[0014]

Embodiment FIG. 1 is a side view of the photoreceptor and developing device portions of an image forming apparatus such as a copying machine to which the present invention can be applied, and FIG. 2 is a side view of the developing device when it is attached to the main body of the image forming apparatus. FIG. The developing device 1 is supported by a guide rail 3 serving as a support member attached to a main body frame 2 of the image forming apparatus by welding or the like, and a developing sleeve 11 faces a drum-shaped photoreceptor 4 with a certain minute gap therebetween. It is positioned and installed. That is, the guide rail 3 has a plate-shaped portion consisting of a support surface 31 that is a flat surface and a guide surface 32 that is a flat surface on the opposite side, and the guide rail 3 has a plate-shaped portion that is composed of a support surface 31 that is a flat surface and a guide surface 32 that is a flat surface on the opposite side.
2a is supported by the support surface 31.

Further, on the upper surface of the flange portion 12, a front projection 12b and a rear projection 12c are provided at the front and rear ends, respectively. On the other hand, a stopper 5 as a stopping member is provided at the front end of the guide rail 3 at a position where the projections 12b, 12c come into contact when the guide rail 3 is mounted. The stopper 5 is
It is attached to the side surface of the guide rail 3, and is bendable so as to retreat from the mounting direction when the front projection 12b and the rear projection 12c come into contact with it when the developing device is mounted. In this combination of protrusion and stopper, the front protrusion 12b is set in the main body of the developing device, and the rear protrusion 12c is
is used to prevent the developing device from falling when pulled out from the main body.

The application of bias to the developing sleeve 11 is as follows:
As shown in FIG. 3, the bias terminal 13 is attached to the non-rotating shaft 11a of the developing sleeve 11, and its lead wire 1
4 from the front side to the rear side, and when the developing device is inserted into the main body of the copying machine, the bias receptacle 1 on the main body side is connected to the rear side.
This is done by combining with 5.

The bias lead wire 14 is covered with a bias terminal cover 16 as a cover member. Then, place the surface 16a of the bias terminal cover 16 opposite to the surface covering the lead wires to face the guide surface 32 of the guide rail 3, and bring it as close as possible without touching the guide surface 32, as shown in FIG. , the developing device 1 is disposed so as to have a small gap δ that allows the developing device 1 to be smoothly attached and detached.

The rear end of the surface 16a of the bias terminal cover 16 is an inclined surface 16b that is inclined in a direction away from the guide surface 32, that is, in a downward direction.

The length x of this inclined surface 16b in the attachment/detachment direction is
As shown in FIG. 5, when the developing device is installed, before the rear side plate 17, which is the other side plate of the developing device, reaches the effective image width L, which is the image area of the photoreceptor 4, the starting point 16 of the inclined surface
The length is such that b-1 reaches the front end of the guide rail.

With this configuration, as shown in FIG. 6, when the flange portion 12 of the developing device is inserted into the guide rail 3, the slope 16b is provided, so that the flange portion 12 and the bias terminal cover 16 are not connected to each other. The opening widens to facilitate insertion.

On the other hand, after insertion, the slope ends before the rear side plate 17 enters the image effective width L, so the distance between the guide surface 32 of the guide rail 3 and the surface 16a of the bias terminal cover 16 becomes small (δ ) Absorbs vertical play, and prevents the rear plate 17 from hitting the image area surface of the photoreceptor 4 and damaging it.

As shown in FIG. 2, if a stopper device is provided above the flange portion 12 and above the support surface 31 of the guide rail, it becomes possible to precisely regulate the widthwise position of the developing device. On the other hand, it becomes difficult to control the vertical position of the flange portion 12 from the top or side surface of the guide rail. However, according to the present invention, since the surface 16a of the bias terminal cover 16 is brought close to the guide surface 32 as described above, the vertical position of the developing device when it is attached or detached can be easily regulated. However, it goes without saying that the present invention can also be effectively applied to devices in which the developing device is slid toward the photoreceptor after insertion, as shown in FIGS. 7 to 11.

In the above-described copying machine, a part of which is shown in FIG. 1, an original image is formed as an electrostatic latent image on the photoreceptor 4 by exposure using various devices (not shown) and a normal image forming process. The toner image is developed by the developing device 1, transferred to a copy sheet being conveyed, and then heat-fixed thereon to complete the image, and then discharged to the outside to make a copy.

[0024]

As described above, according to the present invention, in the invention of claim 1, the opposite surface of the cover member and the opposite flat surface of the support member are connected to each other by a distance sufficient to allow the developing device to be smoothly attached and detached. Since the developing devices are disposed facing each other with a gap between them, vertical movement of the developing device is prevented during attachment and detachment. In this case, since the cover member is also used as a vertical movement regulating member, cost reduction can be achieved with a simple structure.

In the invention of claim 2, in addition to the above, the other end of the opposite side of the cover member is formed into an inclined surface inclined in a direction away from the support member, so that insertion into the support member is facilitated. can do.

[0026] In the third aspect of the invention, when the developing device is installed, the inclined surface is made to have no loose ends before the side plate reaches the image surface, so that damage to the image surface can be prevented. can.

In the fourth aspect of the invention, since the protrusion protruding from the supported portion and the stop member are provided at a position abutting the protrusion of the support member, it is possible to prevent the developing device from coming off and falling when pulled out. In this case, the presence of the protrusion makes it difficult to regulate the vertical position of the supported part, but this can be made possible by the cover member.

[Brief explanation of the drawing]

FIG. 1 is a side view of a photoreceptor and a developing device portion of an image forming apparatus according to an embodiment.

FIG. 2 is a perspective view showing a state in which the developing device is attached to the main body of the image forming apparatus.

FIG. 3 is a sectional view of a developing sleeve of the developing device.

FIG. 4 is a side view of the developing device.

FIG. 5 is an explanatory diagram of the length of the inclined surface of the bias terminal cover of the developing device.

FIG. 6 is a side view showing a state in which the developing device is attached to the main body of the image forming apparatus.

FIG. 7 is a side view of a photoreceptor and a developing device portion of a conventional image forming apparatus.

FIG. 8 shows a guide rail of a conventional developing device, (a)
is a plan view and (b) is a side view.

FIG. 9 shows a flange portion of a conventional developing device, with (a) being a plan view and (b) being a side view.

FIG. 10 is a plan view showing a state in which a flange portion of a conventional developing device is inserted into a guide rail and slid toward a photoreceptor.

FIG. 11 is a plan view showing a state in which a flange portion of a conventional developing device is inserted into a guide rail and slid toward a photoreceptor.

FIG. 12 is a sectional view of the developing sleeve of the developing device.

FIG. 13 is a side view of the developing device.

[Explanation of symbols]

1 Developing device 2 Main body frame (main body of image forming apparatus) 3
Guide rail (supporting member) 4
Photoreceptor 5 Stopper (stop member) 11 Developing sleeve 12 Flange portion (supported portion) 12a Flat surface 12b Front projection 12c Rear projection 14 Lead wire (electric wire) 16 Bias terminal cover (cover member) 16a
Opposite surface 16b Inclined surface 16b-1 Starting point of inclined surface 31 Support surface (flat surface) 32 Guide surface (opposite flat surface) δ
interval

Claims (4)

[Claims] 1. An image forming apparatus comprising a photoconductor, a developing device, and a support member supporting the developing device, wherein the photoconductor extends from one side of the image forming device to the other side, and the developing device The device includes: a supported portion having a flat surface extending from the one side to the other side and serving as a portion on which the developing device is supported; a developing sleeve facing the surface of the photoreceptor with a gap therebetween; an electric wire that is introduced on the other side and applies a bias to the developing sleeve; and a cover member whose surface opposite to the surface covering the electric wire faces the flat surface of the supported portion at a predetermined distance. and is removable from one side to the other side or from the other side to one side,
The image forming apparatus, wherein the support member is fixed to the image forming apparatus main body and has a plate-shaped portion having a flat surface that supports the flat surface of the supported portion and an opposite flat surface that is parallel to the flat surface. An image forming apparatus characterized in that the opposite surface of the cover member and the opposite flat surface of the support member face each other with a gap sufficient to allow smooth attachment and detachment of the developing device. 2. The image forming apparatus according to claim 1, wherein the other end of the opposite surface of the cover member has an inclined surface inclined in a direction away from the support member. 3. When the developing device is mounted, the starting point of the inclined surface reaches one side end of the supported portion before the other side plate of the developing device reaches the image area of the photoreceptor. The image forming apparatus according to claim 2, characterized in that: 4. The supported part includes a protrusion that protrudes at both ends of the one side and the other side opposite to the flat surface to be supported; 2. The developing device further comprises a stop member that retreats from the mounting direction when the developing device hits the projection when the developing device is mounted, and stops the developing device when it comes into contact with the projection when the developing device is pulled out. 3. The image forming apparatus according to 3.