JPH085490Y2 - Cleaning device with elastic blade - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cleaning device having an elastic blade mounted on a process unit equipped in an image forming apparatus.

[Prior art and its drawbacks]

An image forming apparatus such as an electrostatic copying apparatus or a laser beam printer includes a cleaning device that removes toner remaining on the surface of a photoconductor of a so-called rotating drum. As a cleaning device, a device including an elastic blade that acts on a photoconductor has been widely put into practical use in recent years.

However, this type of cleaning device has the following problems to be solved. In the image forming apparatus, a sheet member such as recording paper may be wound around the peripheral surface of the rotating drum as a kind of so-called jam. In the case of such a jam, when the elastic blade is pressed against the rotating drum, the sheet member is sandwiched between the elastic blade and the rotating drum, and a part of the sheet member is broken during the jam processing and remains in the machine, or The sheet member to be removed causes problems such as scratches on the photoconductor.

[Purpose of device]

The present invention has been made in view of the above facts, and its main purpose is to allow the elastic blade to be separated from the surface of the photosensitive member by an operation of gripping the process unit when the process unit is detached from the apparatus main body. An object is to provide an improved cleaning device.

<Means for Solving the Invention> According to the present invention, in order to achieve the above-mentioned main object, the apparatus moves between a working position acting on a photoconductor disposed in a unit frame of a process unit and a non-working position separated from the photoconductor. In a cleaning device comprising an elastic blade freely mounted in the unit frame and a biasing means for biasing the elastic blade toward the working position, a pair of upwardly projecting walls is provided on an upper wall of the unit frame. An operation for moving the elastic blade to the non-acting position against the action of the biasing means, provided with a handle recess formed by the projecting wall and a connecting wall connecting the upper ends of the pair of projecting walls. A cleaning device, wherein an intermediate portion of a lever is rotatably attached to the pair of protruding walls, and an operation portion of the operation lever is operably disposed in the handle recess.

[Specific example of device]

 Hereinafter, further details will be described with reference to the accompanying drawings.

In FIG. 1 showing a part of an image forming apparatus such as an electrostatic copying apparatus having a specific example of a cleaning apparatus according to the present invention, a process unit 2 shown in the figure is detachably attached to an apparatus main body of the image forming apparatus. The unit frame body 4 is provided. The unit frame body 4 is composed of a pair of end walls 6 arranged at intervals in a predetermined direction (direction perpendicular to the paper surface in FIG. 1).
(Only one of which is shown in FIG. 1) having a pair of such end walls 6
In between, rotating drum 10, charging corona discharger 12, developing device
14 and a cleaning device 16 are provided.

In the specific example, the rotary drum 10 is a hollow cylindrical drum body.
Shafts 17 (not shown) provided at both ends of the drum body 17 are rotatably mounted between the end walls 6. An electrostatic photoconductor is arranged on the peripheral surface of the drum body 17. Further, an upper wall 18 is provided between the upper ends of the pair of end walls 6, and downwardly depending hanging walls 20 and 22 are provided on the lower surface of the upper wall 18, and a part of the upper wall 18 and the hanging wall are provided. The walls 20 and 22 serve as the housing for the charging corona discharger 12. Corona wire 24 is stretched in this housing,
A mesh-shaped metal plate 26 for controlling the electric charge applied to the rotary drum 10 is arranged in the opening of the housing.

Further, the developing device 14 includes the pair of end walls 6 of the unit frame body 4.
It has a developing housing 28 mounted between them. An opening 30 is formed on the left side of the developing housing 28 in FIG. 1, and a magnetic brush mechanism 32 is arranged in this opening. The magnetic brush mechanism 32 is composed of a sleeve 36 which is rotated in a direction indicated by an arrow 34 and a permanent magnet 38 which is disposed inside the sleeve 36. A blade 40 is further provided in the opening of the developing housing 28, and the free end of the blade 40 is pressed against the surface of the sleeve 36. At the bottom of the developing housing 28, there is provided a stirring portion 42 for feeding the one-component developer consisting of only magnetic toner toward the magnetic brush mechanism 32 while stirring. In the developing device 14, the developer is magnetically held on the surface of the sleeve 36 by the action of the permanent magnet 38. Then, the developer thus held is conveyed in the direction indicated by the arrow 34 by the rotation of the sleeve 36, and the blade 40 removes the excess developer.
36 Remove from surface.

Next, the cleaning device 16 will be described. The illustrated cleaning device 16 includes a housing wall 46.
Both ends of the housing wall 46 are connected to the pair of end walls 6 of the unit frame body 4. A lower part of the housing wall 46 defines a toner collecting chamber 48, and an elastic blade 50 is arranged above the toner collecting chamber 48. Referring also to FIG. 2, the base portion of the elastic blade 50 is fixed to the substantially L-shaped support plate 52. The support plate 52 is movably attached to the rotary drum 10 in a direction of approaching and separating from the rotary drum 10.
Between the upper bent portion 52a of 52 and the upper end of the housing wall 46,
A pair of biasing springs 54 (constituting biasing means) are arranged at intervals in the longitudinal direction of the support plate 52. Therefore, the support plate 52 is located at the position shown in FIG.
The rear end 52 abuts the inner surface of the housing wall 46 to prevent movement beyond the above position) and the position shown in FIG. 1 and is elastic in the position shown in FIG. 50 is held in a non-working position away from the rotating drum 10, while in the position shown in FIG. 1, the elastic blade 50 is held in its working position where its free end is pressed into contact with the surface of the rotating drum 10, By the action of the biasing spring 54, the elastic blade 50 is held in the above-mentioned action position.

The cleaning device 16 further includes an operation lever 56 for moving the elastic blade 50 to the non-acting position. In the specific example, the upper wall 18 of the unit frame body has a pair of protruding walls 58a and 58b protruding upward and the pair of protruding walls 58a and 5b.
A handle recess formed by a connecting wall 58c that connects the upper end of the handle 8b is provided, and a through hole formed in the protruding walls 58a and 58b forming the handle recess is provided in the middle of the operation lever 56. A pair of shafts 59 (only one of which is shown) are rotatably mounted. At one end of the operating lever 56, an operating portion 60 extending between the protruding walls 58a and 58b is provided.
The operating portion 60 is operably disposed in the handle recess. In addition, an operating portion 62 extending downward is provided at the other end of the operating lever 56. As described above, the protruding walls 58a and 58b that form the handle recess and the connecting wall 58c that connects the upper ends of the protruding walls 58a and 58b function as a handle when the process unit 2 is attached to or removed from the apparatus main body. Since the operating portion 60 of the operating lever 56 is arranged along the inner surface of the connecting wall 58c, the operating portion 60 can be easily operated while holding the connecting wall 58c. In addition, a rectangular opening 64 is formed in the center of the support plate 52 in the longitudinal direction, and the operating portion 62 of the operating lever 56 is received in the opening 64 through an opening 66 formed in the upper wall of the housing wall 46. ing. Therefore, by operating the operation portion 60 of the operation lever 56, the elastic blade 50 can be moved as described later.

In the image forming apparatus including the process unit 2, the rotary drum 10 is rotated in the direction indicated by the arrow 68,
During such rotation, the charging corona discharger 12 is rotated by the rotating drum 10.
A charge of characteristic polarity is given to the surface of the. Then, light having image information is projected onto the surface of the rotating drum 10 as indicated by the one-dot chain line arrow in FIG. 1, thus forming an electrostatic latent image corresponding to the image information on the surface of the photoconductor of the rotating drum 10. It
The developing device 14 supplies toner to the electrostatic latent image on the photoconductor, and thus the electrostatic latent image is developed into a toner image. The toner image is transferred to a sheet member such as recording paper. The elastic blade 50 in the cleaning device 16 is held in the operating position shown in FIG. 1 by the action of the biasing spring 54,
Therefore, its free end acts on the surface of the photoconductor of the rotary drum 10 with a required pressure to remove the toner remaining on the photoconductor after transfer from the surface, and the removed toner is collected in the toner collecting chamber 48. It

To release the pressed state of the elastic blade 50, the operating lever 56 is indicated by an arrow 70 (FIG. 1) by grasping the connecting wall 58c that constitutes the upper wall 18 of the unit frame and the operating portion 60 of the operating lever 56. Just turn it in the direction. As a result, as shown in FIG. 3, the operating portion 62 of the operating lever 56 acts on the support plate 52, and the elastic blade 50 is moved via the support plate 52 in the direction away from the rotary drum 10, thus the elastic blade 50. Are held in the inoperative position shown in FIG. Since it is as described above, in order to release the pressed state of the elastic blade 50, it is sufficient to operate the operation lever 56.
When the sheet member is wrapped around the elastic member 50, the operation state of the elastic blade 50 can be released by operating the operating lever 56 as described above. It can be easily removed without damaging it.

Although one specific example of the cleaning device according to the present invention has been described above, the present invention is not limited to this specific example, and various modifications and corrections can be made without departing from the scope of the present invention.

<Effect of the Invention> Since the cleaning device having the elastic blade according to the present invention is configured as described above, when the sheet member wound around the photoconductor is removed, the process unit is provided in the unit frame to remove it from the main body of the device. When grasping the connecting wall that forms the recess for the handle, the operation portion of the operation lever is also operated at the same time. Therefore, it is possible to release the pressure contact state of the elastic blade by operating the operation portion of the operation lever at the same time only by grasping the connecting wall that constitutes the recessed portion for the handle of the unit frame. And can be removed quickly.

[Brief description of drawings]

FIG. 1 is a sectional view showing an essential part of a process unit including a cleaning device according to the present invention. 2 is a perspective view showing an operation lever for releasing the pressure contact state of the elastic blade and its vicinity in the cleaning device of FIG. FIG. 3 is a sectional view showing a main part of the process unit shown in FIG. 1 in a state where the elastic blade is in a non-acting position. 2 …… Process unit 10 …… Rotating drum 14 …… Developing device 16 …… Cleaning device 50 …… Elastic blade 52 …… Support plate 54 …… Biasing spring 56 …… Operating lever

Claims (1)

[Scope of utility model registration request] 1. An elastic blade movably mounted in a unit frame of a process unit so as to be movable between a working position acting on a photoconductor and a non-working position separated from the photoconductor, A cleaning device comprising a biasing means for biasing an elastic blade toward the operating position, wherein a pair of projecting walls projecting upward and an upper end of the pair of projecting walls are connected to an upper wall of the unit frame. A handle recess formed by the wall and an intermediate portion of an operating lever that moves the elastic blade to the non-acting position against the action of the biasing means is rotatably attached to the pair of projecting walls. A cleaning device, characterized in that the cleaning device is mounted and the operation part of the operation lever is operably disposed in the handle recess.