JPH04311969A - Image formation device - Google Patents

Abstract

PURPOSE:To enable process cartridges of different sizes to be mounted. CONSTITUTION:A guide member 2 is free to move relative to another guide member 3 via a gap. The slant surface 2a of the guide member 2 is pushed by the slant surface 12a of a slider 12 exposed to the pressing force of a compression spring 11. As a result, a small process cartridge with the guide member 2 pressed to a stopper 10 can be mounted or demounted without any need of operation. When a large process cartridge is inserted, the end 12b of the slider 12 is pushed and an inlet guide section 2c is also pushed. The guide member 2 is thereby caused to retreat, and enter space between guide members 2 and 3. Then, a hook 2b is engaged with another hook 14. In this state, when the process cartridge is pulled out, a lever 18 projected from the guide member 2 to the front of the process cartridge is pushed, and a wire 39 is pulled, thereby pulling the rear end of the hook 14. As a result, the hooks 14 and 2b are separated from each other, thereby releasing a lock condition, and original state is restored due to the spring force of the compression spring 11.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to image forming apparatuses such as copying machines and printers employing an electrophotographic method.

0002

[Prior Art] In recent years, in image forming apparatuses employing electrophotography, process cartridges that integrate at least an image forming unit including a photoreceptor are increasingly being used for the purpose of downsizing the main body of the apparatus and making it maintenance-free. are doing. However, the types of process cartridges include black process cartridges and color (e.g. red, blue, green, etc.) process cartridges, and even the same black process cartridge can be used for various processes with different external sizes depending on the size of the device body. Cartridge is present.

0003

[Problems to be Solved by the Invention] However, if the external sizes of the various types of conventional process cartridges described above are the same, it is sufficient to fix the guide portion that guides the process cartridge to a predetermined position within the apparatus main body. , inconvenience occurs in the following cases.

[0004] For example, there are process cartridges of different sizes due to differences in the size of the main bodies of the apparatuses, and since they are not compatible due to the size differences, users have had to prepare process cartridges for each model. Further, although there is a high need for color process cartridges, there is also the problem that demand is low because they are more expensive than black process cartridges and are used less frequently than black process cartridges. To this end, there is a way to lower the price by reducing the number of copies of the color process cartridge (reducing the toner storage section, that is, reducing the external size). Conversely, it is also conceivable to increase the number of copies (increase in external size) in the black process cartridge in order to lower running costs and lengthen replacement intervals.

As described above, even if there are process cartridges with different external sizes, if the guide section of the process cartridge on the apparatus main body side is fixed, there is a big problem that only process cartridges with the same external size can be accommodated. There was a point.

[0006] The present invention provides an image forming apparatus in which a process cartridge is removably installed in an apparatus main body, by providing a movable guide means for guiding the process cartridge to a predetermined position within the apparatus main body. It is an object of the present invention to provide an image forming apparatus that is compatible with various process cartridges.

[0007]

[Means for Solving the Problems] A first aspect of the present invention is an image forming apparatus in which a process cartridge is removably installed in an apparatus main body. This is an image forming apparatus characterized by being provided with a guide means.

[0008] A second invention of the present invention is characterized in that the guide means has a fixing means for locking in a predetermined position.
This is an image forming apparatus according to the invention.

A third aspect of the present invention is the image forming apparatus according to the second aspect, wherein the guide means has a release means for releasing the fixing means when the process cartridge is attached to and removed from the apparatus main body. It is.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of an embodiment of the invention. Guide member 2
, 3 are used along the guide members 2 and 3 when the process cartridge 1 (FIG. 2) is inserted into and removed from the main body of the apparatus. In this embodiment, the guide member 2 is movable with respect to the side plate 19 of the main body, and the guide member 2 is mounted on a shaft that is perpendicular to the guide members 2 and 3 (parallel to the side plate 19) so that the distance between the guide members 2 and 3 changes. You will be guided by the illustrated guide. The guide member 3 is fixed to the side plate 19 at right angles. The positioning shaft 9 of the photoconductor 5 in the process cartridge 1 is located on the side plate 19.
is fixed. The stopper 10 is fixed to a side plate 19 and determines the position of the guide member 2. The compression spring 11 urges the slider 12 in the direction of arrow B. Slider 12 guided by guide 13 in a direction perpendicular to side plate 19
has a slope portion 12a whose tip is sloped in part, and presses against the slope 2a of the guide member 2. The guide 13 serves to guide the slider 12 movable in parallel to the guide member 2. The hook 14 is fitted onto a shaft 15 having a fixed intermediate portion and is rotatable around the shaft 15.
One end of the tension spring 17 is locked to the end opposite to 4a, and the other end of the tension spring 17 is locked to a stationary part, and the hook 14 is biased counterclockwise. The hook 14 is adapted to engage with a hook 2b protruding from the guide member 2. The bar 18, which is slidably fitted to the guide member 2, is connected to the end of the hook 14 on which the tension spring 17 is engaged, via the guide post 16, by a wire 39. The tip of the bar 18 has a hemispherical shape and maintains the position shown in FIG. 3 where it is pulled by the tension spring 17 via a wire 39.

FIG. 2 is a longitudinal cross-sectional view of an image forming apparatus embodying the present invention, in which a process cartridge 1 is connected to guide members 2 and 3.
It is guided and supported in a fixed position. The process cartridge 1 includes a developing section 4, a photoreceptor 5, a cleaning device 6, and a primary charger 7. Moreover, the broken line in FIG. 2 indicates the position of the guide member 2 after it has moved (after it has spread).

Next, how the process cartridge 1 is attached and detached will be explained using the plan views shown in FIGS. 3 to 5. In FIG. 3, a standard size process cartridge 20 is inserted in the direction of arrow A and attached to the main body of the apparatus. The position of the process cartridge 20 attached to the main body is indicated by a two-dot chain line. In this case, since the process cartridge 20 is of standard size, the guide member remains fixed without moving. In other words, since the slider 12 is biased in the direction of arrow B by the compression spring 11, the slope portion 12a of the slider 12 is biased toward the guide member 2.
The process cartridge 20 is pressed against the slope 2a of the process cartridge 20.
The guide member 2 is set so as not to move in the direction of arrow D when inserted in the direction of arrow A. This prevents the guide member 2 from moving when the process cartridge 20 is inserted,
Its purpose is to perform a normal guiding function.

FIG. 4 shows a process cartridge that is larger than a standard size process cartridge (such as a process cartridge with a larger toner accommodating section due to the increased number of copies, etc.).
This figure shows how the process cartridge 21 (process cartridge compatible with other models) is inserted. Since the width L2 of the process cartridge 21 is wider than the interval L1 between the guide members 2 and 3, the process cartridge 21 is inserted along the entrance guide portion 2c of the guide member 2. In this case, the tip end 12b of the slider 12 is pushed by the process cartridge 21, so it starts moving in the direction opposite to the arrow B direction, and at the same time, the process cartridge 21 pushes the inlet guide part 2c, so the guide member 2 moves in the arrow D direction. Moving. In other words, the distance between the guide members 2 and 3 is gradually widened. Furthermore, since the hook 14 is pulled in the direction of arrow C by the tension spring 17, the hook 2b and the hook 1 are moved as the hook 2b of the guide member 2 moves.
4 will engage once. At this point, the distance between the guide members 2 and 3 becomes L2, and the process cartridge 21 can be inserted. Then, the bar 18 whose tip is protruding from the guide member 2 is pushed and passed, and the bar 18 is projected by the force of the tension spring 17 in the state shown in FIG. At this time, the hooks 2b and 14 are once disengaged, but then engaged again. Moreover, as described above, since the guide member 2 is locked by the engagement of the hook 2b and the hook 14, the process cartridge 21
The guide member 2 does not move during insertion.

FIG. 5 shows a state in which the installation of the large-sized process cartridge 21 has been completed. Further, in this configuration, when the large-sized process cartridge 21 is pulled out from the main body of the apparatus, the state is automatically returned to the state (FIG. 3) in which a standard-sized process cartridge can be handled. In FIG. 5, when the large process cartridge 21 is removed from the apparatus main body (in the direction of arrow I), the bar 1
8 is pushed out in the direction of arrow E. Then, the wire 39 connected to the bar 18 is connected to the hook 1 via the guide post 16.
4 begins to rotate clockwise against the force of the tension spring 17 and is disengaged from the hook 2b. When the engagement is released, the guide member 2 becomes freely movable toward the guide member 3, and the slider 12, which has been pushed in the direction of arrow B by the compression spring 11, returns to its original state (FIG. 3), so that the guide member 2
It also begins to move in the opposite direction to the direction of arrow D, hits the stopper 10, and stops. With the above configuration, the guide member interval is automatically changed to enable attachment and detachment of process cartridges having different external sizes.

FIG. 6 shows an exploded perspective view of another embodiment. This moves the guide members 22 and 23. The guide members 22 and 23 are movable in the EF direction so as to change the interval by a guide (not shown). Guide member 22
, 23 are provided with protrusions 24, 28, 33, respectively, which engage with elongated holes 25, 32, 36 in the side plates 19, 31, 34. Elongated holes 25, 32, and 36 are positioning holes 2
The protrusion 24 has the same length as the pitch between 6, 27 and 37, 38,
The movement limit that 28 and 33 can move is determined. Also, positioning holes 26, 27, 37, 38 are also provided in the guide members 22, 23.
The positions of the guide members 22 and 23 can be changed by inserting and removing the positioning pins 30 and 35 (dotted line portion).

FIG. 7 shows a cross section of the positioning pin 30. The positioning pin 30 is biased in the direction of arrow H by a tension spring 40 whose one end is locked to the pin 30 and the other end is locked to the side plate 29, and is always engaged with the positioning hole 26, but the guide member 22, 23, pull the positioning pin 30 in the direction of arrow G (for example, by holding it by hand) until the positioning hole 26 is moved.
It is sufficient to take it out once, move the guide members 22 and 23, and then return the positioning pin 30 to its original position.

In another embodiment, as shown in FIG.
). Further, in the first embodiment of the present invention, only one of the two guide members is movable, but it goes without saying that both may be movable.

In the embodiment, there are two types of guide member intervals of the process cartridge, but it goes without saying that three types of intermediate positions may be used.

[0019]

Effects of the Invention As explained above, by making the guide member that guides the process cartridge movable when installing the process cartridge in the apparatus main body, it is possible to accommodate various process cartridges with different external sizes. be.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the invention.

FIG. 2 is a longitudinal sectional view of an image forming apparatus embodying the present invention.

FIG. 3 is a plan view showing when the process cartridge is inserted.

FIG. 4 is a plan view showing when the process cartridge is inserted.

FIG. 5 is a plan view showing when the process cartridge is inserted.

FIG. 6 is an exploded perspective view showing another embodiment.

FIG. 7 is a longitudinal sectional view of a positioning pin portion of another embodiment.

FIG. 8 is a front view of another embodiment.

[Explanation of symbols]

1 Process cartridge 2, 3 Guide member 2a Guide member slope 2b Hook 2c Entrance guide part 12 Slider 12a Slider slope 12b Slider tip

Claims (3)

[Claims] 1. An image forming apparatus in which a process cartridge is removably attached to an apparatus main body, further comprising a movable guide means for guiding the process cartridge to a predetermined position within the apparatus main body. Device. 2. The image forming apparatus according to claim 1, wherein the guide means has a fixing means that is locked in a predetermined position. 3. The image forming apparatus according to claim 2, wherein the guide means includes a release means for releasing the fixing means when the process cartridge is attached to and removed from the apparatus main body.