JPH0727315B2 - Release mechanism for cleaning member in image forming apparatus - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device in an image forming apparatus such as an electrophotographic copying machine, and in particular, a device in which a photoconductor, a cleaning device, a developing device and the like are combined into one unit. The present invention relates to a cleaning member releasing mechanism for an electrophotographic copying machine, which has a structure that is detachable from a main body.

(Prior Art) Conventionally, for example, an electrophotographic copying machine including a photosensitive drum, a developing device, a cleaning device, and the like, which are integrated with each other and are provided with a process unit configured to be detachably attached to a copying machine main body, has been proposed. Known (for example, JP-A-57-2111)
81). In such an electrophotographic copying machine, when the color of an image to be copied on a copy sheet is changed, the process unit having a developing device accommodating a desired toner color is replaced and the photoconductor drum reaches its service life. In this case, the process unit having a new photosensitive drum can be replaced and used again.

However, since the cleaning blade of the cleaning device in the process unit is in constant contact with the surface of the photosensitive drum at a predetermined blade pressure, the process unit is stored in a dedicated storage box and left unused for a long time, for example. If so, permanent distortion of the blade may occur, or the material of the drum at the contact portion between the blade and the photoconductor drum may change (drum film crack, etc.), which may shorten the life of the cleaning blade and the photoconductor. .

(Object of the Invention) The present invention solves the above-mentioned technical problem, and when the process unit is housed in the storage box, the contact of the cleaning member is not released to shorten the life of the cleaning member and the photoconductor. An object of the present invention is to provide a cleaning member releasing mechanism in an image forming apparatus.

(Structure of the Invention) According to the present invention, a process unit having at least a photosensitive member and a cleaning device having a cleaning member for removing residual toner contacting the surface of the photosensitive member is detachably provided to an apparatus main body. In the image forming device
A cleaning member is provided on a rotatably supported shaft, and an urging means for bringing the cleaning member into contact with the surface of the photosensitive member is provided, and the process unit is detached from the apparatus main body and accommodated in a storage box on the shaft. When this is done, an operating piece is provided for rotating the shaft in a direction in which the cleaning member comes into contact with the protrusion of the storage box and releases the contact of the cleaning member with the photosensitive member.

With this configuration, when the process unit is detached from the apparatus main body and housed in the storage box, the contact of the cleaning member is released, and the cleaning member is separated from the surface of the photoconductor.

(Embodiment) FIG. 1 is an overall configuration diagram of an electrophotographic copying machine in which a cleaning blade releasing mechanism of the present invention is adopted.

In FIG. 1, a contact glass 2 on which an original is placed is provided on an upper part of a housing 1 of an electrophotographic copying machine.
A document retainer 3 is arranged above the contact glass 2. A document irradiation lamp 4, a reflector plate 5, and a condenser lens assembly 6 are provided in the housing 1, and these components constitute an optical system. Around the photosensitive drum 7 that receives light from this optical system, the main charging device 8, the developing device 9, the transfer device 10, and the charge eliminating brush 1 are arranged in this order in the rotation direction.
1, a cleaning device 12 and the like are provided. The photosensitive drum 7, the main charging device 8, the developing device 9 and the cleaning device 12 are housed in a unit case 13 and are detachable from the housing 1 of the copying machine body.
Make up 14.

The developing device 9 includes a toner hopper 15 having a toner supply roller 15a and containing toner, and a developing container 16 having a toner stirring roller 16a and a developing roller 16b. The cleaning device 12 includes a shaft 17 rotatably supported by a cleaning case 12a, and a shaft 17
Is provided with a cleaning blade 18 for removing the residual toner on the photosensitive drum 7, an operating member 19 (see FIG. 2) described later provided at the tip of the shaft 17, and the like.

On the downstream side of the developing device 9 in the rotation direction of the photoconductor drum 7 and on the upstream side of the transfer device 10 in the copy paper conveyance direction, relatively,
A transport roller 20 for transporting the copy paper to the transfer device 10 is provided near the periphery of the photoconductor drum 7, and a peeling pad 22 is provided on the upstream side of the transport roller 20 in the copy paper transport direction via a guide plate 21. A conveyance roller 23 whose outer periphery is in contact with is provided. A paper feed tray 25 to which the copy paper is sent by a paper feed roller 24 is provided on the upstream side of the carry roller 23 in the copy paper carrying direction.
Is set.

A transport belt assembly 26 is provided on the downstream side of the static elimination brush 11 in the transport direction of the copy paper, and further, a fixing device 27 having a heat roller 27a is provided, and a discharge roller 28 is provided on the downstream side of the fixing device 27. A paper discharge tray 29 for receiving copy paper via is set.

2 (a), (b) and (c) are a sectional view of a cleaning device, a side view of the cleaning device, and a perspective view of an operating member for explaining a cleaning blade releasing mechanism that is a feature of the present invention. FIG. 3 is a perspective view of the process unit and a partial sectional perspective view of the dedicated storage box, and FIG. 4 is a side sectional view showing a state in which the process unit is stored in the dedicated storage box.

In each of the above drawings, one end of the cleaning blade 18 is attached to the shaft 17 by the pin 18a via the attachment member 18b. The operating member 19 is attached to the tip of a shaft 17 protruding from the side surface of the cleaning case 12a to the outside, and one end of which is locked to the cleaning case 12a.
An engaging piece 19a engaged with the other end of a spring (urging means) 31 for bringing the surface of the blade into contact with a predetermined blade pressure, and an operating piece for rotating the shaft 17 in a direction for releasing the blade pressure as described later. It consists of 19b. The engaging piece 19a of this operating member 19
The cleaning blade 18 is brought into contact with the surface of the photosensitive drum 7 by the spring 31 engaging with the shaft 31, and the back surface of the operating piece 19b is rotated by the shaft 17.
When is pressed counterclockwise, the cleaning blade 18 is separated from the surface of the photosensitive drum 7. At both ends of the cleaning case 12a, there are a seal member 12b for receiving the toner scraped off by the cleaning blade 18 so as not to leak to the outside, and a toner scraped off by the cleaning blade 18 and remaining on the surface of the photosensitive drum 7. A seal member 12c is provided to prevent leakage to the outside.

The cleaning device 12 is housed in a unit case 13 as shown in FIG. However, this unit case
In addition, the process unit such as the photoconductor drum 7, the main charging device 8, and the developing device 9 is accommodated in the inside of 13, as described above. The unit case 13 is provided with an opening 13a for irradiating the original image from the condenser lens assembly 6 onto the photosensitive drum 7 and a handle band 13b used when carrying the unit case 13 on the upper part thereof. A fan-shaped actuating hole 13c that allows the tip of the actuating piece 19b of the actuating member 19 to protrude to the outside and be rotatable by a predetermined angle is provided on the side portion, and a handle 13d.

In the exclusive storage box 41 in which the unit case 13 is stored,
A projection 42 for rotating the shaft 17 in a direction for releasing the blade pressure (contact) of the cleaning blade 18 is provided inside of which the back surface of the operating piece 19b protruding from the operating hole 13c of the unit case 13 abuts.

Next, the operation of the cleaning blade 18 when the process unit 14 attached to the housing 1 of the copying machine main body is removed and stored in the dedicated storage box 41 in order to change the color to be copied on copy paper, for example, will be described. To do.

The unit case 13 of the process unit 14 is removed from the main body housing 1, and the unit case 13 is housed in the dedicated storage box 41 so that the back surface of the operating piece 19b abuts and presses the projection 42 of the dedicated storage box 41. As a result, the back surface of the operating piece 19b is pressed, and the shaft 17 is rotated counterclockwise. Therefore, the blade pressure of the cleaning blade 18 is released,
The tip of the blade 18 is separated from the surface of the photosensitive drum 7, and the process unit 14 is stored and stored in the dedicated storage box 41 in this state. In this way, since the cleaning blade 18 is stored with the blade pressure released, the permanent distortion of the blade 18 may occur or the material of the drum 18 may change at the contact portion of the photosensitive drum 7. Is prevented.

Although the cleaning blade is used as the cleaning member in the above embodiment, the cleaning brush is not limited to the cleaning blade and may be used. Further, although the above-described embodiment is adopted in the electrophotographic copying machine, the invention is not limited to this, and may be adopted in other image forming apparatus such as a facsimile.

(Effects of the Invention) As described above, according to the present invention, in an image forming apparatus including a process unit detachably attached to the apparatus body, the process unit is detached from the apparatus body and stored in a storage box. At this time, by providing an operating piece that abuts the protrusion of the storage box and rotates the shaft of the cleaning member in the direction of releasing the contact of the cleaning member with respect to the photoconductor against the urging force from the urging means, When the process unit is housed in the storage box, the cleaning member separates from the surface of the photoconductor, so that it is possible to prevent permanent distortion of the cleaning member and change of the photoconductor material at the contact portion between the cleaning member and the photoconductor. The life of the member and the photoconductor is not shortened.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an electrophotographic copying machine adopting a cleaning blade releasing mechanism according to an embodiment of the present invention, and FIG. 2 (a) is a sectional view of a cleaning device provided in the electrophotographic copying machine. 2 (b) is a side view of the cleaning device, FIG. 2 (c) is a perspective view of an operating member included in the cleaning device, and FIG. 3 is a process unit included in the electrophotographic copying machine. FIG. 4 is a perspective view of a unit case and a storage box for storing the process unit, and FIG. 4 is a side sectional view showing a state in which the process unit is stored in the storage box. 1 ... Housing (apparatus main body), 7 ... Photoconductor drum (photoconductor), 12 ... Cleaning device, 14 ... Process unit, 17 ... Shaft, 18 ... Cleaning blade (cleaning member), 19b ... Actuator, 13 ...... Spring (biasing means), 41 …… Storage box, 42 …… Projection.

Claims (1)

[Claims] 1. An image forming apparatus in which a process unit having at least a photoconductor and a cleaning device provided with a cleaning member that comes into contact with the surface of the photoconductor and removes residual toner is detachably attached to the apparatus main body. At
A cleaning member is provided on a rotatably supported shaft, and a biasing means for bringing the cleaning member into contact with the surface of the photosensitive member is provided. The process unit is provided on the shaft in a storage box removed from the apparatus main body. When housed,
A mechanism for releasing a cleaning member in an image forming apparatus, comprising an operation piece for rotating the shaft in a direction of releasing contact of the cleaning member with the photoconductor by contacting a protrusion of the storage box.