JPH0480393B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a developing device used in a copying machine or the like capable of making multicolor monochrome copies.

<Prior Art> When replacing a developer tank with a developer tank containing a different color developer in a copying machine capable of making multi-color monochrome copies, the developer tank is replaced from the front of the copying machine. At this time, a method has been used in which the developer tank fixing device is released, the developer tank positioning device is then released, and the developer tank is slid to the front and taken out.

Here, the developer tank fixing device allows the developer tank to move freely in the sliding direction (direction perpendicular to the paper feeding direction).
A claw-like locking mechanism or a lid is required to prevent the developing tank from moving due to vibrations during use of the copying machine. The fixing device is a mechanism that prevents the developer tank from moving in the sliding direction.

Further, in the positioning device, the distance between the magnet roller of the developer tank and the photosensitive drum (hereinafter referred to as DSD) is an important dimension in order to obtain good image quality.
In order to obtain this DSD accurately, a positioning device is required. The positioning device holds collars at both ends of the roller shaft of the magnet roller, and secures DSD by bringing the collars into contact with the photosensitive drum so that there is a gap for DSD in the radial direction of the collar.

That is, the developer tank positioning device is for bringing the collar into pressure contact with the photoreceptor.

Conventionally, the developer tank was brought into pressure contact with the photoreceptor to ensure the above-mentioned DSD by using a lever or the like from behind the developer tank.

<Problems to be solved by the invention> As a result, there is a difference in the pressure applied to the color before and after the developer tank, and the pressure applied to the color before and after the developer tank becomes stable.
The drawback was that it was difficult to obtain DSD.

In view of the above problems, the present invention aims to provide a developing device that can stabilize the pressure applied to the front and rear spacing collars.

<Means for Solving the Problems> In order to solve the above-mentioned problems, the present invention releases the developer tank 3 in the axial direction a fixing plate 11 of a fixing device pivotably supported on the front part of the copying machine main body 9 so as to be fixed in the direction of rotation; A pair of front and rear positioning devices 6 are provided, each of the positioning devices 6 comprising: a rotary plate 13 rotatably supported on the copying machine main body 9 via a support shaft 12; Pin guide groove 1 formed on the bottom of
4, the guide groove 1 protruding from one end of the rotary plate 13;
4, an elastic body (spring 16) for biasing the pressure contact pin 15 in the direction of pressure contact with the developer tank; A connecting plate 22 is provided, which is composed of a spacing collar 17 for maintaining a predetermined distance from the circumferential surface of the body 2, and moves in the axial direction of the main shaft 1 in conjunction with the opening/closing operation of the fixed lid 11. The plate 22 has connection holes 23 into which the connection pins 21A and 21B at the other end of each rotating plate 13 are fitted.
A, 23B are formed, and the connecting holes 23A, 23B are such that when the fixed lid 11 is open, the connecting pins 21A, 21B abut against the hole walls of the connecting holes 23A, 23B, and when the fixed lid 11 is closed. In this state, the connecting pins 21A and 21B are connected to the connecting hole 2.
The position and size of the press pin 15 are set so that it fits loosely into the pins 3A and 23B, and when the fixed lid 11 is closed,
Each elastic body (spring 16) is configured to press the developing tank 3 independently.

<Function> In the above-mentioned means for solving the problem, a developer tank fixing device is provided to prevent the developer tank 3 from moving during the copying operation, but it is necessary to release this device when taking out the developer tank. The fixing device is released, and the rotating plate 13 connected to the connecting plate 22 is moved to the supporting shaft 12 in FIG.
When the developer tank 3 is rotated (counterclockwise) to the position shown by the solid line in FIG. , positioning is canceled before and after that. In this state, the developer tank 3 is pulled out of the main body 9 along the guide rail 4, and another developer tank 3 is inserted along the guide rail 4.

Then, when the fixing device 5 is closed, the rotary plate 13 is rotated around the support shaft 12 by the spring 16, and the pressure contact pin 15 is moved from the end of the linear groove 14B to the arcuate groove 14A.
The developer tank 3 is brought closer to the photoreceptor 2 by sliding toward the side (the state shown by the chain line in FIG. 4). The developer tank 3 is stopped and positioned at a position where the collar 17 of the magnet roller 8 and the photoreceptor 2 come into contact with each other. In this state, the developer tank 3 is urged toward the photoreceptor 2 by the spring 16 at its front and rear portions.

In this way, a spring 16 is attached to each of the two rotating plates 13.
By providing these, it becomes possible to apply independent pressure contact to the front and rear parts of the developer tank 3.

<Example> Hereinafter, an example of the present invention will be described based on FIGS. 1, 2, 3, and 4.

FIG. 1 is a side view of a fixing device, positioning device, and interlocking device showing one embodiment of the present invention, FIG. 2 is a front sectional view of a developing device, and FIG. 3 is a released state of the interlocking device and positioning device. FIG. 4 is a plan view showing the interlocking device and the positioning device in a press-contact state.

As shown in the figure, the developing device of the present invention includes a drum-shaped photoreceptor 2 that is rotatable around a main shaft 1, a developer tank 3 disposed close to the photoreceptor 2, and a developer tank 3 that is rotated in the axial direction of the main shaft 1. The photoreceptor 2 is provided with a guide rail 4 which can be freely pulled out in the X direction and which guides the photoreceptor 2 in a direction perpendicular to the main shaft 1 so as to be able to approach and move away from the photoreceptor 2.

The axial direction X of the main shaft 1 of the developer tank 3
a developer tank fixing device 5 for preventing movement to;
a pair of front and rear positioning devices 6 for positioning the developer tank 3 at a predetermined position in a direction perpendicular to the main shaft 1; An interlocking device 7 is provided for interlocking the fixing device 5 and the positioning device 6 so that the positioning device 6 performs a positioning operation in conjunction with the developer tank fixing operation of step 5.

The developer tank 3 is formed in a box shape with an open front.
A magnet roller 8 is supported inside.

The guide rail 4 is plate-shaped and is used to place and guide the developing tank 3.

The fixing device 5 consists of a fixed lid 11 whose lower part is pivotally supported on the front part of the copying machine body 9 via a left and right shaft 10 so as to be rotatable in opening and closing, and the upper end of the fixed lid 11 is in contact with the main body 9. Ru.

The positioning device 6 is provided at both the front and rear ends of the developer tank 3.
an L-shaped rotary plate 13 whose central bent portion is rotatably supported on the main body 9 via a support shaft 12; a pin guide groove 14 formed on the bottom surface of the developer tank 3;
The guide groove 14 is provided protrudingly from one end of the rotating plate 13.
A developer tank pressure contact pin 15 that is removably engaged with the developer tank 3; a spring 16 that biases the pressure contact pin 15 in the direction of pressure contact with the developer tank 3; and a disc-shaped collar 17 that comes into contact with the circumferential surface of the end portion of the photoreceptor 2.

The collar 17 is formed to have a diameter that optimizes the gap between the magnet roller 8 and the circumferential surface of the photoreceptor 2.

As shown by the chain line in FIG. 3, the guide groove 14 includes an anti-circular groove portion 14A centered on the support shaft 12, and a straight groove portion that allows the developer tank 3 to be drawn out in a straight line toward the front when the fixed lid 11 is open. It consists of 14B. Also,
An arcuate through hole 18 is formed in the guide rail 4 at a position corresponding to the arcuate groove 14A to allow the pressure pin 15 to swing in the arcuate groove 14A.

The interlocking device 7 connects the lower end of the fixed lid 11 and the other end of each rotary plate 13 with connecting pins 20, 21.
It is composed of a connecting plate 22 connected by A and 21B. A lower piece 22A is formed at the front end of the connecting plate 22, and the connecting pin 20 has an axial direction that is the same as the left-right axis 10, and connects the lower piece 22A to the lower end of the fixed lid 11. Also, the connecting pin 21A,
21B is the rotating plate 13 whose axial direction is the vertical direction.
is fixed to the other end.

On the other hand, the connecting plate 22 has the connecting pins 21A, 2
Square holes 23A and 23B are formed to engage 1B.

On the other hand, each of the tension springs 16
The other end side and the front protrusions 24A, 24B of the connecting plate 22
It is interposed between.

Then, when the pressure contact pin 15 is released, the connection pins 21A and 21B are connected to the square holes 23A and 23B.
The connecting pins 21A, 21B are configured to be in contact with the front hole wall of the square holes 23A, 23B in a loosely fitted state when the pressure contact pin 15 is in pressure contact.

In the above configuration, when replacing the developer tank 3 to change the developed color, it is necessary to remove it from the main body. If the collar 17 for DSD is pulled out while in contact with the photoreceptor 1, the photoreceptor 1 will be damaged, so the developing tank 3 must be removed after the positioning is released.

Furthermore, a fixed lid 11 is provided to fix the developer tank so that the developer tank 3 does not move during the copying operation, but this needs to be released. When the fixed cover 11 is opened and fixed, the fixed cover 11 rotates open around the left-right axis 10 and moves the connecting plate 22 of the interlocking device 7 rearward. Therefore, the rotary plate 13 connected to the connecting plate 22 rotates around the support shaft 12 (counterclockwise) in FIG. 3 and reaches the position shown by the solid line in FIG. 3. That is, the positioning device 6 of the developer tank 3, which was pressed against the developer tank 3 by the spring 16 in the photoreceptor proximity direction (photoreceptor positioning direction), is released. In this state, the developer tank 3 is pulled out of the main body 9 along the guide rail 4, and another developer tank 3 is pulled out from the guide rail 4.
Insert along.

Then, when the fixing lid 11 of the fixing device 5 is closed,
The rotary plate 13 is rotated around the support shaft 12 by the spring 16, and the press pin 15 slides from the end of the linear groove 14B toward the arcuate groove 14A, bringing the developer tank 3 close to the photoreceptor 2 (Fig. 4). (state shown by the dashed line). The developer tank 3 is stopped and positioned at a position where the collar 17 of the magnet roller 8 and the photoreceptor 2 come into contact with each other.
In this state, the developer tank 3 is urged toward the photoreceptor 2 by the spring 16 at its front and rear portions.

In this way, a spring 16 is attached to each of the two rotating plates 13.
By providing these, it becomes possible to apply independent pressure contact to the front and rear parts of the developer tank 3.

In the released state shown in FIG. 3, the connecting pins 21A and 21B are inserted into the square holes 23A and 23B on the connecting plate 22.
The rotating plate 13 is held in pressure contact with the support shaft 1.
2 to prevent it from swinging in the pressure contact direction.

In addition, in the press-contact state shown in FIG. 4, the connecting plate 22
By pulling in the direction of the arrow, the connecting pin 21A,
21B is released, and the rotary plate 13 is swung by each spring 16 to press the pressure contact pins 15 against the developer tank 3 independently.

That is, in the square holes 23A and 23B of the connecting plate that support the connecting pins 21A and 21B (points of emphasis) that operate the pressure rotary plate 13, by supporting only one direction and leaving the other direction free, the developing tank is exposed to light. After moving in parallel in the direction of approaching and separating the developer tank and pressing against the photoreceptor, the front and rear sides of the developer tank can be independently pressurized by freeing the support in the square holes 23A and 23B.

It should be noted that the present invention is not limited to the above embodiments, and it goes without saying that many modifications and changes can be made to the above embodiments within the scope of the present invention.

<Effects of the Invention> As is clear from the above explanation, in the present invention, when taking out the developer tank, the fixing device is released,
Rotating plates in front and behind the developer tank are rotated against the biasing force of an elastic body, and when the developer tank is inserted, the rotary plate is rotated around the spindle by the elastic body and the pressure contact pin slides in the guide groove. The developer tank is moved closer to the photoreceptor.
In other words, a pair of front and rear positioning devices are provided for positioning the developing tank near the photoreceptor, and the pair of positioning devices is deactivated in conjunction with the opening/closing operation of the fixing lid of the fixing device. It's easy to do. Moreover, since an elastic body (spring) is provided on each of the two rotary plates, it is possible to apply independent pressure to the front and rear parts of the developer tank, and the pressure applied to the collars at the front and rear of the developer tank is equalized. , it has excellent effects such as providing stable DSD.

[Brief explanation of drawings]

FIG. 1 is a side view of a fixing device, positioning device, and interlocking device showing one embodiment of the present invention, FIG. 2 is a front sectional view of a developing device, and FIG. 3 is a released state of the interlocking device and positioning device. FIG. 4 is a plan view showing the interlocking device and the positioning device in a press-contact state. 1...Spindle, 2...Photoreceptor, 3...Developer tank, 4
... Guide rail, 5 ... Fixing device, 6 ... Positioning device, 7 ... Interlocking device, 15 ... Pressure contact pin, 1
6... Spring, 17... Collar, 18... Through hole,
20, 21A, 21B... Connection pin, 22... Connection plate, 22A... Lower piece, 23A, 23B... Square hole, 24A, 24B... Front projection, X... Axial direction.

Claims (1)

[Scope of Claims] 1. A developer tank disposed close to a photoreceptor that is rotatable around a main shaft, and the developer tank can be freely drawn out in the axial direction of the main shaft and is attached to the photoreceptor in a direction orthogonal to the main shaft. There is a guide rail that guides the rollers so that they can be moved closer and closer together, and a guide rail that can be rotated to open and close at the front of the copying machine so that the developer tank is released in the axial direction of the main shaft in the open state and fixed in the axial direction of the main shaft in the closed state. a pivotally supported fixed lid; and a pair of front and rear positioning devices for positioning the developer tank at a position close to the photoreceptor in a direction perpendicular to the main shaft, each positioning device having a support shaft attached to the copying machine main body. a rotating plate rotatably supported via a pin guide groove formed on the bottom surface of the developing tank; a developing tank protruding from one end of the rotating plate and removably engaged with the guide groove. Consisting of a pressure contact pin, an elastic body for biasing the pressure contact pin in the developer tank pressure contact direction, and a spacing collar for maintaining the developer tank at a predetermined distance from the circumferential surface of the photoreceptor in the positioned state, A connecting plate is provided that moves in the axial direction of the main shaft in conjunction with the opening/closing operation of the fixed lid, and a connecting hole is formed in the connecting plate into which a connecting pin at the other end of each rotary plate is fitted. The connecting hole is positioned such that the connecting pin contacts the hole wall of the connecting hole when the fixed lid is open, and the connecting pin fits loosely into the connecting hole when the fixed lid is closed. and a size are set, and the pressing pin is configured to press the developing tank independently by each elastic body when the fixed lid is closed.