JP3025892B2 - Image forming device - Google Patents

Description

The present invention relates to an electrophotographic image forming apparatus for forming an image on a transfer material such as a copying machine or a printer.

[Background of the Invention]

In an image forming apparatus such as an analog copying machine using an electrophotographic method, a copying machine or a printer using a semiconductor laser / LED scanning system, when a photosensitive member having a durable life, a developer carrier, a cleaning member, and a developer toner are consumed. For replenishment / replacement, a part of the image forming means or a cartridge conventionally used in a personal copying machine, a small printer, or the like is formed, and an integral part of the image forming means is taken out of the apparatus for maintenance or maintenance. Are configured to perform an exchange. On the other hand, various configurations have been proposed in which a transfer path of a transfer material on which an image is formed by an image forming unit is opened so that the transfer material can be easily taken out during jam processing.

As a typical configuration thereof, a photosensitive drum, a developing device, a cleaner, and the like as disclosed in JP-B-58-54392 are integrally attached to a support member, and can be pulled out from the apparatus main body. Japanese Patent Application Laid-Open No. 57-154255 discloses a device which facilitates repair, and a device in which the main parts of these image forming means are integrated and disposable. JP-A-59-14 discloses a printer configuration for forming a latent image on a photoreceptor drum by dot exposure, scanning and writing.
No. 7366 discloses a configuration in which the upper casing of the divided structure is opened to open the transfer material transport path and take out the transfer material in the event of a jam, and further discloses the disposable cartridge described above. In this publication, a disposable process cartridge is replaceable in an upper housing having a two-part structure, and the operability of replacing the cartridge and the easiness of jam clearance are intended to be solved. With particular emphasis on the ease of replacement of the process cartridges, particularly the replenishment toner cartridge and the recovery toner cleaning cartridge, the process cartridge is divided into two parts, and especially the process cartridge is placed in the lower housing to improve the workability of maintenance. The above-mentioned method is disclosed in JP-A-58-1161.

In particular, the above structure is a vertical type.
Nos. 4058, 63-244059, 63-244064, JP-A-1-
Japanese Patent Application Publication No. 179168 and the like have proposed a device in which the same-direction operation and the improvement of jam processing are improved.

[Problems to be solved by the invention]

However, in a process cartridge in which the developing device and the image carrier can be exchanged with respect to the apparatus main body, loading and unloading to and from the apparatus main body are easy to handle, and the developing device is inserted into and removed from the apparatus main body. There has been no proposal of a compact image forming apparatus having a process cartridge free from such problems as leakage of toner or developer, scumming, and the like, and especially in the case of jam processing of a transfer material.

In particular, a disposable cartridge is provided in an upper housing of a two-part structure which facilitates the jam processing.
A process cartridge is provided in the lower housing in order to facilitate replacement of the toner supplied in JP-A-72159 and the replacement of the collected toner, and a process cartridge for developing, cleaning, and photosensitive drums is lifted upwards during jam processing. In the structure disclosed in Japanese Patent Application Laid-Open No. 58-1161, the workability of replacement and the ease of jam clearance are contradictory,
Furthermore, even if the process cartridge is replaced with a paper feed / transport system below these process cartridges, or the cartridges are strictly sealed by external vibration or impact to the machine body to prevent toner spillage, etc. Toner spills from the cleaner portion, which causes stains inside the apparatus and transfer paper.

Japanese Patent Application Laid-Open No. 58-190961 discloses a two-part structure, in which a process cartridge provided in the upper housing when the upper housing is opened is always kept horizontal as a measure against spilling of waste toner. However, although the loading / jam processing is easy, the problem is solved for toner bleeding / mocking etc. at the time of loading / jam processing from the downward developing section or cleaner section, or other maintenance replacement operation etc. It was not a simple and effective configuration to make it possible.

On the other hand, a printer as shown in FIG. 2 of Japanese Utility Model Application Laid-Open No. 63-195357 is disclosed as a configuration capable of avoiding such structural defects. The printer also has a built-in process cartridge therein and forms a flat feed conveyance path at the top. However, the toner image surface on which the image is transferred faces downward and is fixed from the transfer material separating portion of the photosensitive drum 1 at the same time. Department
The transport path up to 26 is limited, so the problem of the transport section has not been solved, and furthermore, the simplicity of jam clearance when splitting into two, and the overall compactness due to the stack paper feed configuration of the upstand In particular, the device is not always excellent in operability for a user, for example, when the shaft 27 is divided into two parts around the fulcrum, the opening angle of the upper housing is restricted.

In recent years, a configuration using a compact cartridge and solving the same problem of transportability, jam clearance, and configuration in the same direction have been disclosed in
No. 40850, No. 63-244059, etc., but a second paper feed roller (transfer material registration roller) for timing the transfer material sent from a normal paper feed cassette and the photosensitive drum is used. The structure should be timed only by the paper feed roller (transferring material feed roller). However, compactness and structure are not necessarily simplified. In particular, as shown in FIG. 5, the outline of the transfer material transport path is of a vertical type, which facilitates processing in the event of a jam. , Especially when pulling out the guide line 107
If a force is not applied in parallel, a squeezing force is generated between the guide members, and a smooth pulling action cannot be performed.

For this reason, it is difficult for the user to perform the mounting / dismounting operation or the inserting operation, and in particular, toner shading or leakage occurs due to the vibration of the loss at the guide end at the time of mounting / dismounting, and the user is not always provided with satisfactory operability.

As a result of solving and improving this point, the present invention facilitates replacement of consumables, maintenance and replacement of materials, and jam processing, and furthermore, all of the above operations can be performed from the same side of the apparatus. It is intended to provide an image forming apparatus.

[Means for solving the problem]

An object of the present invention is to provide a divisible image forming apparatus in which a process cartridge including at least a replaceable photosensitive member, a developing device, and a cleaning device can be inserted, wherein the process cartridge is housed in an openable housing, and The casing can be divided and opened while leaving the transfer unit at least on the image forming apparatus main body side, and in the closed state of the casing, the process cartridge is at the first position where image formation is possible; With the opening of the housing, the process cartridge rotates about a rotation fulcrum provided on a side surface and moves to a second position in which a gap between the developing device and the cleaning device and the photosensitive member is on the upper side. In the image forming apparatus, the process cartridge is capable of being inserted and removed upward in the second position.

〔Example〕

1 to 4 show an embodiment of the image forming apparatus according to the present invention.

In FIG. 1, reference numeral 1 denotes a photosensitive drum having an outer peripheral surface as a photosensitive member, reference numeral 2 denotes a charger, and reference numeral 3 denotes a scanning optical system for performing laser exposure by a device for writing a document image on the photosensitive member.

Reference numeral 4 denotes a developing device for developing the latent image on the photoconductor formed by the writing device 3, and reference numeral 5 denotes a cleaning device for cleaning residual toner on the photoconductor after image transfer.

On the other hand, 11 is a paper cassette for storing transfer paper, and 12 and 13
Is a roller for carrying out and feeding the transfer paper, 14 is a transfer unit, 15 is a separator, 16 is a fixing roller, and 17 and 18 are a discharge roller and a discharge tray.

The image forming and transferring processes in the image forming apparatus are performed as follows.

The photoreceptor drum 1 is applied with a potential to the photoreceptor by corona discharge of the charger 2 while rotating in the direction of the arrow by driving the shaft 1A.

The photosensitive member to which the potential is applied is subjected to exposure scanning of a document image based on a signal from a separate reading device in the writing device 3 to form an electrostatic latent image.

Next, the latent image is developed by the developing sleeve 4A of the developing device 4 to be a toner image, and is conveyed to the transfer section of the transfer device 14 by the rotation of the photosensitive drum 1.

On the other hand, the transfer paper is conveyed out one sheet by the operation of the unloading roller 12 from the paper feeding cassette 11, and the lower conveying unit 601A is synchronized with the toner image via the paper feeding roller 13 in timing.
And is fed to the transfer unit.

The fed transfer paper receives the charge of the transfer unit 14 in a state of being in close contact with the photoreceptor and transfers the toner image, and is then discharged by the separator 15 to be separated from the photoreceptor.
After being conveyed to the fixing roller 16 through the 601B to fuse the toner image, the toner image is discharged onto the discharge tray 18 via the discharge roller 17.

At the same time, the photosensitive drum 1 from which the transfer paper is separated removes and cleans the residual toner on the photosensitive member by the cleaning device 5 and enters the next image forming process.

The photosensitive drum 1 is housed in an integrated cartridge including a charging device 2, a developing device 4, and a cleaning device 5 having a cleaning blade 5A and a cleaning roller 5B, and the like. The image forming apparatus is also housed in a housing 10 constituting the left side of the image forming apparatus.

On the other hand, the paper feed cassette 11, the rollers 12 and 13 for conveyance and paper feed, the transfer device 14, and the separator 15 are further provided with a fixing roller 16, a paper discharge roller 17, a paper discharge tray 18 and the like in the image forming apparatus. It is individually incorporated in the apparatus main body 20 constituting the right side.

The housing 10 is opened from the apparatus main body 20 through a support shaft 10A as shown in FIG. 2 so as to be almost vertically, preferably after transfer / separation, to rub the toner on the transfer material. The transfer paper transport path configured by providing an inclination of several degrees to tens of degrees in the opposite direction to the body surface portion is connected to the lower transport section 60 of the housing 10.
The apparatus body 20 corresponding to each of the cartridge side transport unit 602A of the cartridge 1A and the cartridge side transport unit 602B of the upper transport unit 601B
The upper and lower transport plates 603A and 603B can be divided into left and right sides, so that the transfer paper can be easily cleared of jams, and at the same time, the process cartridge 6 is removed from the developing device 4 and the cleaning device 5 By bringing the gap between the photoreceptor drum 1 and the photosensitive drum 1 at the top of the opening when the toner is opened, it is possible to attach / detach / replace the toner without causing toner bleeding or leakage. The transfer material transfer surface of the cartridge side transfer units 602A and 602B is preferably formed of a surface having a plurality of ribs in parallel with the transfer direction in order to make the transfer material flow as good.

The process cartridge 6 is supported at a predetermined position in the apparatus by a mechanism shown in FIG.

The figure shows details of the mechanism provided in the housing 10 and the apparatus main body 20.
Is indicated by a dashed line. Upper / lower transport section 601A, 601
Although the passage side plate shown in B is an example provided in the apparatus main body 20, the side surface of the cartridge may be a transfer surface as shown in FIGS.

The process cartridge 6 includes a pair of support pins 6A on both outer surfaces thereof, and the support pins 6A are engaged with and supported by a pair of opposed U-shaped bearing portions 10B on the inner surface of the housing 10. It is supported so as to be able to swing around the support pin 6A as a fulcrum.

Further, when the protrusion 6B provided on the bottom surface of the process cartridge 6 is pressed by the pressure contact lever 19 on the apparatus main body 20 side, the process cartridge 6 comes into contact with a stopper 10C fixed to the housing 10 to regulate its posture, and Each image forming means including the drum 1 is set at a predetermined position.

That is, the press-contact lever 19 is constantly urged counterclockwise around the shaft 19A as a fulcrum by a strong tension spring 19B, thereby holding the process cartridge 6 to the support pin.
The cartridge 6 is rotated clockwise about the fulcrum 6A, and accurately holds the process cartridge 6 at the first position, that is, a position where image formation is possible.

In this state, the process cartridge 6 is positioned at the center of gravity W
Are biased clockwise more than immediately below the support pin 6A, and thus, a habit of rotating in the counterclockwise direction is given.

When the housing 10 is rotated counterclockwise with the support shaft 10A as a fulcrum as shown in FIG. 4 and the transfer paper conveyance path is opened, the process cartridge 6 is released from being pressed by the press-contact lever 19, and has its own center of gravity due to its own weight. Until the position W occupies the position immediately below the support shaft 10A, it rotates counterclockwise and is placed at the second position in a so-called suspended state. At this time, the regulating plate 20A formed by the apparatus main body 20 slides on the bottom surface of the process cartridge 6 to prevent rapid rotation at the beginning of rotation.

Further, as the process cartridge 6 rotates, the driven gear G1 fixed to the shaft 1A of the photosensitive drum 1 is separated from the drive gear G2 on the housing 10 side to automatically release the meshing relationship.

Therefore, in the above-mentioned second position, the process cartridge 6 has the balanced developing device 4 with the center of gravity position W directly below.
In addition, a stable posture is obtained in which the gap between the cleaning device 5 and the photosensitive member is directed upward, so that the attached handle 6C can be raised and easily removed or attached.

As the above-mentioned handle 6C, a handle that is always urged counterclockwise by a torsion spring or the like and automatically returns to a folded state after use is used.

Further, when the casing 10 is rotated clockwise from the state shown in FIG. 4 to close the casing 10, the process cartridge 6 starts to slide again on the bottom surface of the process plate 6A, so that the process cartridge 6 is closed as the closing proceeds. The cartridge 6 is forcibly rotated clockwise.

As a result, immediately before the process cartridge 6 returns to the first position, the projecting portion 6B enters the pressing range of the press-contact lever 19, and the press-contact and the cooperative action of the lever 19 and the regulating plate 20A cause the process cartridge 6 to move. 6 is restored to the first position shown in FIG. 3, whereby the driven gear G1 meshes with the drive gear G2 to return the photosensitive drum 1 to a position where power can be transmitted. In addition, as shown in FIG. 4, when the casing 10 is opened by a jam processing or the like, the upper and lower transport side plates 602'A, 602 '
It is also possible to set B at a position where the maintenance operation can be easily performed by rotating around the support shafts 604A and 604B in the state shown by a dashed line in the drawing by a connecting portion or a driving mechanism (not shown) with the opening. .

〔The invention's effect〕

According to the present invention, it is very easy to deal with transfer paper jams and other troubles, and at the same time, it is possible to easily attach / detach / replace the process cartridge including the photoconductor, and to prevent toner bleeding and leakage when the divided housing is open. As a result, the cartridge is located in a state where no cartridge is provided, and as a result, a high quality image can always be obtained by excellent handling and thorough maintenance.
Although an operation can be performed with a device configuration in which the front side in the drawing is the front side, an image forming apparatus that can easily perform one-way operation with the cassette insertion / discharge side facing the front is provided.

[Brief description of the drawings]

1 and 2 are cross-sectional views of the image forming apparatus of the present invention, FIGS. 3 and 4 are explanatory views showing the main components of the apparatus, and FIG. FIG. DESCRIPTION OF SYMBOLS 1 ... Photoreceptor drum, 2 ... Charger 3 ... Writing device 4, Developing device 5 ... Cleaning device 6 ... Process cartridge 6A ... Support pin, 6B ... Projection part 6C ... Handle, 10 ... Housing 10A ... Support shaft, 10B ... Bearing part 10C ... Stopper, 19 ... Press-contact lever 19B ... Tension spring, 20 ... Device body 20A ... Regulator plate G1 (G2) ... Drive (drive) )gear

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tadayoshi Ikeda 2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica Corporation (72) Inventor Hisao Sato 2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica Corporation Inspector Hideki Suzuki (56) reference Patent Sho 63-15262 (JP, a) JP Akira 56-144467 (JP, a) JP flat 2-64566 (JP, a) (58 ) investigated the field (Int.Cl. ⁷ G03G 15/00 550 G03G 21/16-21/18

Claims (2)

(57) [Claims] 1. A dividable image forming apparatus in which a process cartridge including at least a replaceable photosensitive member, a developing device, and a cleaning device can be inserted, wherein the process cartridge is housed in an openable housing. The casing can be divided and opened while leaving the transfer unit at least on the image forming apparatus main body side. When the casing is in the closed state, the process cartridge is at the first position where image formation is possible. A second position in which the process cartridge is rotated about a rotation fulcrum provided on a side surface with the opening of the housing, and a gap between the developing device and the cleaning device and the photosensitive member is positioned upward; To
An image forming apparatus, wherein the process cartridge can be inserted and removed upward in the second position. 2. The image forming apparatus according to claim 1, wherein a part of a transfer surface of a transfer paper transfer path is provided on a side surface of the housing.