JPH08123281A - Image forming device - Google Patents

Abstract

PURPOSE: To provide an image forming device capable of realizing the press contact-separation of a blade and the toner receiving member corresponding to the image carrier at a low cost and with a small sized structure. CONSTITUTION: The image forming device is provided with the blade equipped with the cam follower 35 for scraping off the residual toner on the image carrier at the time of coming in press contact with the image carrier and while integrally rocking, the toner receiving member equipped with the cam follower 43 for receiving the toner scraped off by the blade at the time of press contact with the image carrier and while integrally rocking, the blade cam 51 capable of coming in contact with the cam follower 35 of the blade, holding the blade in press contact with the image carrier at the time of scraping off the residual toner and separating after scraping off, and the receiving member cam 52 capable of coming in contact with the cam follower 43 of the toner receiving member, holding the toner receiving member in press contact with the image carrier precedingly with respect to the blade and separating from the image carrier laggingly with respect to the blade.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as an electrophotographic copying machine, a printer or a facsimile. More specifically, the residual toner on the image carrier after transfer is scraped by pressing a blade. The present invention relates to an image forming apparatus for removing and removing.

[0002]

2. Description of the Related Art As an image forming method for a color copying machine, a color printer, a facsimile or the like, for example, an electrostatic latent image forming step and a developing step are repeated a plurality of times while the image bearing member is rotated a plurality of times, so that the image bearing member is formed. A method has been proposed in which toner images of several different colors are superposed on the peripheral surface and are collectively transferred to a sheet (Japanese Patent Laid-Open No. 60-75850). This method has the advantages that the entire apparatus is small and simple and the cost is low.

By the way, residual toner adheres to the peripheral surface of the image carrier after the toner image is transferred onto the paper. Therefore, after the residual toner is removed from the image carrier by the cleaning means, a new electrostatic latent image is formed and an image is formed. As such a cleaning means, a blade made of a material such as rubber having an appropriate hardness has been conventionally used. In this blade, one edge portion of the blade is brought into pressure contact with the surface of the image carrier with an appropriate pressing force due to its elastic force to scrape off the residual toner. There is also an apparatus in which a toner receiving member having an elastic thin plate such as rubber is pressed against the image carrier below the blade to receive the residual toner scraped off by the blade.

Here, in the method of forming a toner image by rotating the image carrier a plurality of times, the blade and the toner receiving member are separated from the image carrier so as not to damage the toner image during the formation of the toner image. The blade and the toner receiving member are brought into pressure contact with the image carrier only during cleaning, and the drive thereof is generally performed by a solenoid. Moreover, in order to surely receive the toner scraped off by the blade by the toner receiving member, the toner receiving member is pressed against the image bearing member in advance of the blade, and the toner receiving member is delayed from the blade and separated from the image bearing member. Therefore, the blade and the toner receiving member are respectively provided with solenoids separately.

[0005]

However, as described above, when the solenoid is used for the pressure contact / separation of the blade and the toner receiving member of the image carrier, a considerable space is required for the arrangement, and the cost is low. Since it is expensive, there is a problem that the device becomes large and the cost is high. Moreover, since the blade and the toner receiving member need to be provided with solenoids separately, the above problem is further increased.

On the other hand, the blade also has a problem that the toner becomes cylindrical in the pressure contact portion with the image bearing member and is easily accumulated and fixed. Particularly, the pressure contact position of the blade is the horizontal center of the image bearing member. In the case where the toner is arranged above the line, the accumulated toner is unlikely to peel off and fall due to its own weight, so that such toner fixation is remarkable. When the lump of toner fixed to the blade in this way is sandwiched between the image carrier and the blade, the state of pressure contact between the blade and the image carrier becomes poor, and the residual toner may be scraped off completely. I can't.

The present invention has been made in view of the above circumstances, and its first object is to form an image in which the blade and the toner receiving member can be pressed / separated from the image carrier with an inexpensive and compact structure. A second object is to provide an image forming apparatus capable of reliably removing the toner attached to the blade with a simple configuration.

[0008]

In order to achieve the above first object, the first invention is such that the toner is swingable so as to come into pressure contact with and separate from an image carrier, and remains on the image carrier at the time of pressure contact. Is scraped off by the movement of the image carrier, and a blade provided with a cam follower that swings integrally with the image carrier is swingable so as to come into pressure contact with and separate from the image carrier, and is scraped by the blade at the time of pressure contact. And a toner receiving member that is provided with a cam follower that swings integrally with the blade, and a cam follower of the blade that can come into contact with the toner receiving member, and when the residual toner is scraped off, the blade is moved through the cam follower. Can be contacted with the cam for the blade and the cam for the blade, which is pressed against the image carrier and oscillated so as to be separated from the image carrier after being scraped off. And a cam for the toner receiving member that causes the toner receiving member to come into pressure contact with the image carrier prior to the blade via the cam follower and oscillates so as to be separated from the image carrier behind the blade. It is characterized by having.

In order to achieve the above-mentioned second object, the second invention is such that it can swing so as to come into pressure contact with and separate from the image carrier.
The toner remaining on the image carrier at the time of press contact is scraped off by the movement of the image carrier, and a blade provided with a cam follower that integrally swings is abuttable to the cam follower, and the residual toner is removed. When scraped off, the blade is pressed against the image carrier via the cam follower, and after scraped off, the blade cam is oscillated so as to separate from the image carrier, and the blade is separated from the image carrier. In this state, a part of the blade cam that abuts the cam follower is formed in a convex shape or a concave shape, and an impact generating means that gives an impact to the blade when passing through the cam follower is provided.

[0010]

According to the first aspect of the present invention, the toner receiving member cam is brought into pressure contact with the image bearing member through the cam follower capable of abutting against the toner receiving member cam, and then the blade receiving cam contacts the image bearing member. The blade is pressed against the image bearing member via a contactable cam follower to scrape off the residual toner on the image bearing member by this blade, and the toner receiving member receives the scraped residual toner. Then, after scraping off, the blade cam separates the blade from the image bearing member, and after this, the toner receiving member cam separates the toner receiving member from the image bearing member. in this way,
A blade cam, a cam follower capable of abutting on the blade cam, a receiving member cam, and a cam follower capable of abutting the receiving member cam without requiring a considerable space for its arrangement and using a high cost solenoid. The above-mentioned operation can be realized with this configuration.

According to the second aspect of the present invention, the impact generating means formed in the cam for the blade in a convex or concave shape impacts the blade via the cam follower when the blade is separated from the image carrier. By giving, the toner attached to the blade drops from the blade. Moreover, since the impact generating means is formed by forming a convex shape or a concave shape on the blade cam as described above,
The configuration is simple.

[0012]

【Example】

A. First Embodiment (1) Configuration of First Embodiment A first embodiment according to the first invention will be described below with reference to FIGS. 1 to 4. FIG. 1 shows a main configuration of a multicolor image forming apparatus (image forming apparatus) of the present embodiment. In FIG. 1, reference numeral 10 is provided so as to be rotatable in one direction (clockwise in FIG. 1). 3 illustrates a photosensitive drum as an image bearing member.

An image writing device 13 for irradiating the photosensitive drum 10 with the exposure beam 12 from the laser generator 11 is arranged above the photosensitive drum 10. Further, below the photoconductor drum 10, a paper feed / conveyance device 14 which is arranged at a position on the front side of the rotation of the photoconductor drum 10 and supplies the paper toward the photoconductor drum 10, and a paper feeding / conveyance device 14 which exposes paper to the photoconductor drum 10. A sheet discharging and conveying device 1 which is arranged at the rear side position of the body drum 10 and receives a sheet from the photosensitive drum 10 and discharges the sheet to the outside.
5 and 5 are arranged.

A charging device 17 for charging the photoconductor drum 10 to a predetermined electric charge is opposed to the outer peripheral surface of the photoconductor drum 10 at a position in front of the exposure beam irradiation position by the image writing device 13 of the photoconductor drum 10 so as to be charged. A latent image is formed on the photosensitive drum 10 which is arranged and charged by the charger 17 by irradiation of the exposure beam 12 of the image writing device 13.

Then, the sheet feeding / conveying device 14 is located at the position after the rotation of the photosensitive drum 10 from the exposure beam irradiation position.
A developing device 18 that develops the latent image formed on the photoconductor drum 10 by the image writing device 13 into a color image to form a toner image is arranged at a position closer to the front. The developing device 18 includes a yellow developing device 18 a and a magenta developing device 1 which are sequentially arranged along the rotation direction of the photosensitive drum 10.
8b, cyan developing device 18c and black developing device 1
It is composed of 8d. Here, the photosensitive drum 10 may be provided between the developing device 18 and the paper feeding / conveying device 14 if necessary.
A pre-transfer charger 19 that charges or removes electricity to an optimum state for transfer is disposed.

In addition, the sheet feeding / conveying device 14 is provided at a position downstream of the sheet feeding / conveying device 14 in the rotation direction of the photosensitive drum 10.
A transfer device 21 for transferring the toner image carried on the photoconductor drum 10 to the paper supplied from is arranged, and a separator 22 for separating the paper from the photoconductor drum 10 is further provided at a position downstream thereof. It is arranged in front of the paper transport device 15. Further, a cleaning device 24 for removing the residual toner on the photoconductor drum 10 is arranged at a position downstream of the paper discharge / conveyance device 15, and an image of the photoconductor drum 10 is further provided at a position downstream thereof. A static eliminator 25 for removing electric charges is arranged in front of the charger 17.

Next, the cleaning device 24 of this embodiment will be described. As shown in FIGS. 2 to 4, the cleaning device 24 includes a housing 26 arranged in parallel to the horizontal side of the photoconductor drum 10, a blade 28 and a sealing mechanism (toner receiving member) arranged in the housing 26. And 29. An opening 30 is formed in the housing 26 on the side facing the photoconductor drum 10. Here, the width of the opening 30 in the direction along the axial direction of the photosensitive drum 10 is set to be wider than the width of the image forming area of the photosensitive drum 10 in the same direction.

The blade 28 includes a blade support shaft 32 rotatably supported in the housing 26 in parallel with the photosensitive drum 10, a blade support member 33 fixed to the blade support shaft 32, and one end edge side. And a blade main body 34 that is attached and fixed to the blade support body 33 in a state of protruding. Here, the blade support 33 is formed of a steel plate having a thickness of about 1.5 mm, and the blade main body 34 is formed of hard polyurethane having a thickness of about 2 mm. Then, when the blade support shaft 32 rotates in a predetermined direction, the blade body 34 and the blade support body 33 swing, whereby the blade body 3
Reference numeral 4 has one end edge portion pressed against the photosensitive drum 10 in a state along the axial direction of the photosensitive drum 10. The blade main body 34 is separated from the photosensitive drum 10 by rotating the blade support shaft 32 in the opposite direction.

In this embodiment, a stopper (not shown) for limiting the swinging range of the blade support 33 is arranged. When the blade support 33 is in contact with the stopper, the blade main body 34 is pressed against the photosensitive drum 10 with a predetermined force and can move to the photosensitive drum 10 side from the swing limit position. There is no such thing.

When the photosensitive drum 10 rotates with the blade main body 34 in pressure contact, the photosensitive drum 1
The toner remaining at 0 is scraped off by the blade body 34. Therefore, the blade main body 34 and the blade support 33 have a width equal to or slightly wider than the width of the image forming area in the axial direction of the photosensitive drum 10, and the position in the width direction is also aligned with the position of the image forming area. Has been.

One end of the blade support shaft 32 is projected outward from the housing 26, and a blade release lever (cam follower) 35 is fixed to this projected portion. The blade release lever 35 is disposed orthogonally to the blade support shaft 32, and has a bent shape having two substantially vertical side portions 36 and 37 as shown in FIG. The blade release lever 35 is urged in a predetermined swing direction by a blade spring 38 having one end engaged with the housing 26 and the other end engaged with the end of one side 36, whereby the blade is released. Body 34
Is urged toward the photoconductor drum 10. And
In the state where only this biasing force acts, the blade 28 comes into contact with the stopper and is positioned at the swing limit position described above.

The seal mechanism 29 has a support shaft 40 for sealing which is supported by the housing 26 so as to be rotatable below the support shaft 32 for blades in parallel with the support shaft 32 for blades. It has a sealing support body 41 fixed in 26 and a seal main body 42 fixed to the sealing support body 41 in a state where one end side is projected. The sealing support 41 is made of a steel plate having a thickness of about 0.8 mm, and the sealing body 42 has a thickness of 0.1 mm.
It is formed of a strip-shaped polyurethane film of about mm.

When the seal support shaft 40 rotates in a predetermined direction, the seal body 42 and the seal support body 41 oscillate, whereby the seal body 42 moves.
One end edge portion of the photosensitive drum 10 is lightly pressed against the photosensitive drum 10 along the axial direction. Also, by rotating the sealing support shaft 40 in the opposite direction to the above,
The seal body 42 is separated from the photosensitive drum 10. In this embodiment, a stopper (not shown) that limits the swing of the sealing support 41 is arranged. Then, in the state where the sealing support 41 is in contact with the stopper, the seal body 42 is pressed against the photosensitive drum 10 with a predetermined force, and does not move to the photosensitive drum 10 side from the swing limit position. It is like this.

The seal body 42 receives the toner scraped off and dropped by the blade 28 in a state of being pressed against the photosensitive drum 10. Therefore, the seal main body 42 and the seal support 41 have a width larger than the width of the image forming area in the axial direction of the photosensitive drum 10, and the center position in the width direction is the center of the image forming area in the width direction. It is aligned with the position.

One end of the sealing support shaft 40 is projected outward from the housing 26, and a sealing release lever (cam follower) 43 is fixed to this projecting portion. The seal release lever 43 is arranged orthogonal to the seal support shaft 40, and has a bent shape having two substantially right-angled side portions 44 and 45 as shown in FIG. The sealing spring 46, one end of which is engaged with the housing 26 and the other end of which is engaged with the end portion of the one side portion 44, has the seal main body 4 via the seal supporting shaft 40.
2 is biased toward the photosensitive drum 10, and the seal mechanism 29 is in contact with the stopper and is positioned at the swing limit position in a state where only this biasing force acts.

The blade release levers 35 are arranged so as to be displaced from each other so as to be located farther from the housing 26 than the seal release lever 43. When the blade 28 is located at the rocking limit position, the blade release lever 35 extends the side portion 37 opposite to the side portion 36 engaged with the blade spring 38 in a diagonally downward direction. There is. Further, the seal release lever 43, when the seal mechanism 29 is located at the swing limit position described above,
A side portion 45 opposite to the side portion 44 with which the sealing spring 46 is engaged extends obliquely upward. Moreover, in this state, the side portion 37 and the side portion 45 are arranged so that the positions of the extending tip end portions of the tip end portions 37a and 45a on the tip end side of the swing direction by the urging force of the springs 38 and 46 are the same. There is.

Such a cleaning device 24 is unitized integrally with the photosensitive drum 10 to form a drawer unit 47, which is mounted with the blade release lever 35 and the seal release lever 43 side being the front end side. The image forming apparatus main body 48 is detachably attached so as to be pulled out in the direction.

When the photosensitive drum 10 and the unitized cleaning device 24 are properly attached to the image forming apparatus main body 48, the tip portion 37a of the blade release lever 35 and the tip portion 45a of the seal release lever 43 are provided.
A compound cam 50 supported on the image forming apparatus main body 48 side is disposed on the side of the. The composite cam 50 is rotatably supported by the shaft portion 49 on the image forming apparatus main body 48 side, and has a blade cam 51 arranged on the image forming apparatus main body 48 side and a sealing cam 52 arranged on the housing 26 side. And are integrally formed, and rotate in the clockwise direction in FIG. Here, the blade cam 51 is
The blade release lever 35 urged by the blade spring 38 can be brought into contact with the blade release lever 35 with its axial position aligned. Further, the sealing cam 52 can be brought into contact with the sealing release lever 43 urged by the sealing spring 46 while aligning the axial position thereof.

The shape of the cam surface 51a of the blade cam 51 is such that the height from the center of rotation is the minimum and the starting point P (the upper end position in FIG. 4) coincident with the sealing cam 52 is directed toward the rear side in the rotational direction. The height gradually increases and reaches a maximum at about 90 degrees with respect to the starting point P, and thereafter it is constant until the end point Q at the 180 degree position (lower end position in FIG. 4) and further from the end point Q at the 180 degree position to about 270 degree position. Then, the position is gradually decreased to the position of the starting point P thereafter.

The shape of the cam surface 52a of the sealing cam 52 is such that the height from the center of rotation is substantially constant from the starting point P to a position of approximately 60 degrees rearward in the rotational direction, and thereafter increases to an end point Q of approximately 180 degrees. Is the maximum that matches the blade cam 51,
Further, it gradually decreases from the end point Q of the 180 degree position to the position of approximately 300 degrees, and thereafter becomes constant until the position of the start point P.

The blade cam 51 and the seal cam 52 have the same shape from the starting point P to the 180 ° position in both clockwise and counterclockwise directions in FIG. 4, in other words, the starting point P and the end point Q. It has a mirror-symmetrical shape with respect to the line connecting and. Further, in the state where the starting point P is opposed to the tip end portion 37a of the blade release lever 35 and the tip end portion 45a of the seal release lever 43, these tip end portions 37 at the rocking limit position described above.
There is a slight gap between a and 45a. As a result, the drawer unit 47 can be easily attached to the image forming apparatus main body 48. Further, the compound cam 50 is rotated by a drive motor (not shown) provided on the image forming apparatus main body 48 side, and this drive motor moves the compound cam 50 from the position of the start point P to the position of the end point Q by one drive signal. , Or vice versa, it is rotated by 180 degrees from the position of the end point Q to the position of the start point P.

(2) Operation of First Embodiment First, the overall operation of the image forming apparatus of the first embodiment will be described. The photoconductor drum 10 is rotationally driven, and the charger 1
After being uniformly charged by 7, the latent image corresponding to the toner image of each color is formed by the exposure beam 12 emitted from the laser generator 11 of the image writing device 13, and then the photosensitive drum of the developing device 18 is formed. Toner having the same polarity as the surface potential polarity of 10 adheres to the exposed portion to develop the toner image. Then, such charging, latent image formation, and development are repeated once for each color of toner, a total of four times, and a color toner image is formed on the photoconductor drum 10 in the order of yellow, magenta, cyan, and black.

Then, when the photosensitive drum 10 is charged or discharged by the pre-transfer charger 19 to the optimum state for transfer as required, the color toner image is fed from the paper feeding and conveying device 14. The image is transferred onto the transfer device 21. The paper on which the color toner image is transferred is separated by the separator 22.
After being peeled off from the photoconductor drum 10 by the above, it is sent to a fixing device (not shown) by the paper discharge conveying device 15, and the toner images of four colors are fixed on the paper and then discharged to the outside. In this way, by combining the four color toner images on the photosensitive drum 10 and transferring them on the paper at once, a good image without color misregistration can be obtained. The residual toner on the surface of the photosensitive drum 10 after the transfer is removed by the cleaning device 24.

Next, the operation of the cleaning device 24 will be described. In the state where a color toner image is formed on the photosensitive drum 10 as described above, the cleaning device 2
The composite cam 50 of No. 4 has its end point Q at the tip end portion 37a of the release lever for blade 35 and the release lever for sealing 43,
It is located on the 45a side. As a result, the blade release lever 35 and the seal release lever 43 both come into contact with the composite cam 50 and are pressed to swing against the biasing forces of the blade spring 38 and the seal spring 46, and the blade body 34. The seal body 42 and the seal body 42 are both separated from the photosensitive drum 10. The blade body 34 and the seal body 42 maintain this separated state at least until the untransferred toner image before transfer passes so as not to disturb the toner image.

Then, at a predetermined timing after the untransferred toner image has passed through the cleaning device 24 and immediately before the residual toner reaches the cleaning device 24, a drive motor (not shown) is driven by a single drive signal to generate a composite image. Cam 5
0 starts rotation from the position where the end point Q is horizontal (the position at 9 o'clock in FIG. 4). Then, the height from the center of rotation does not change from the start of rotation to 90.degree.
The blade cam 51 having the blade release lever 3
5 is left as it is, the sealing cam 52 having the cam surface 52a whose height is lowered in advance swings the sealing release lever 43 and presses the sealing body 42 against the rotating photosensitive drum 10. Let

Further, the compound cam 50 continues to rotate over 90 degrees, which delays the height of the cam surface 51a of the blade cam 51 and delays the blade release lever 3.
5, the blade body 34 is pressed against the photosensitive drum 10. Then, the compound cam 50 rotates 180 ° from the initial position and stops at the position where the starting point P is lateral (at 9 o'clock in FIG. 4). In this state, by continuing the rotation of the photosensitive drum 10, the blade body 34
Scrapes off the toner remaining on the photosensitive drum 10. The toner that has fallen in this way will be transferred to the lower seal body 42.
And is guided to the bottom collecting portion 54 of the housing 26.

Then, after the photosensitive drum 10 rotates while the blade body 34 is in pressure contact with the blade to perform cleaning, the composite cam 50 is rotated again at a predetermined timing by a drive motor (not shown). Then, the sealing cam 52 having the cam surface 52a whose height does not change from the start of rotation to 60 ° is increased in advance while the sealing release lever 43 is left as it is.
The blade cam 51 having a comes into contact with the tip portion 37a of the blade release lever 35 and swings it. Then, when the blade body 34 is rotated by 90 degrees, the blade main body 34 is separated from the photosensitive drum 10 whose cleaning is completed by the maximum distance.

Further, the compound cam 50 continues to rotate, and the sealing cam 5 having the cam surface 52a whose height becomes higher later.
2 abuts on the tip end portion 45a of the seal release lever 43 and swings the tip end portion 45a, and at the time when the seal release lever 43 rotates 180 degrees, the seal main body 42 is separated from the photosensitive drum 10 by the maximum distance. After that, the compound cam 50 stops at the position where the end point Q is horizontal (the position at 9 o'clock in FIG. 4). Then, the formation of the next color toner image on the photosensitive drum 10 is started.
The blade main body 34 and the seal main body 42 are provided at least before the first toner image (yellow) carried on the photoconductor drum 10 reaches the cleaning device 24 so as not to disturb the toner image. Drum 10
It is designed to be separated from.

While the image forming apparatus is stopped, the fulcrum P of the compound cam 50 is located at the 9 o'clock position in FIG. 4, and the fulcrum P, the tip portion 37a of the blade release lever 35 and the seal release lever 43 are disposed. There is a gap between the front end portion 45a and the front end portion 45a. Therefore, the cleaning device 24 unitized with the photosensitive drum 10 can be freely pulled out from the image forming apparatus main body 48. what if,
If the fulcrum P is not located at the 9 o'clock position (for example, 3
(When it is arranged at the hour position), the drive motor is rotated by operating an operation stop switch (not shown) or the like, and the composite cam 50 is driven so that its starting point P is at the 9 o'clock position in FIG. To do. When an image is formed after the drawer unit 47 is loaded in the image forming apparatus main body 48, the drive motor is rotated by operating a start switch (not shown) or the like, and the end position Q of the composite cam 50 is set to the blade release lever 35 or the blade release lever 35. It is placed at the 9 o'clock position on the seal release lever 43 side, and thereafter, the formation of a toner image or the like is started.

According to the image forming apparatus of the first embodiment described above, the sealing mechanism 29 is preliminarily pressed against the photosensitive drum 10 by the sealing cam 52 via the sealing release lever 43 which can abut against it. And then the blade cam 5
1, the blade release lever 35 that can come into contact with the blade release lever 35
By pressing the blade 28 against the photosensitive drum 10 via the blade, the blade 28 scrapes off the residual toner on the photosensitive drum 10, and the seal mechanism 29 receives the scraped residual toner. Then, after scraping off, the blade 28 moves the blade 28 by the blade cam 51.
The seal mechanism 29 is separated from the photosensitive drum 10 by the sealing cam 52 after this. Thus, in the above embodiment, the blade cam 5
The above-described operation can be realized with a simple configuration including the blade release lever 35, the sealing cam 52, and the sealing release lever 43, which can abut on the blade. The structure can be greatly simplified and downsized, and the manufacturing cost can be reduced, as compared with the case where a considerable space is required and an expensive solenoid is used.

Particularly in the above embodiment, the blade cam 51 is used.
Since the sealing cam 52 is the coaxially-integrated composite cam 50, the space required for the arrangement can be further reduced, and thus the size can be further reduced.

Further, in the above embodiment, the blade 28 provided with the blade release lever 35 and the seal mechanism 29 provided with the seal release lever 43 are freely drawn out from the image forming apparatus main body 48. Drawer unit 4
7, a composite cam 50 having a blade cam 51 and a sealing cam 52 is provided in the image forming apparatus main body 48. For this reason, when the pull-out unit 47 is pulled out and attached to the image forming apparatus main body 48, the drive force transmission system is disconnected and connected by the blade cam 51 and the seal cam 52, the blade release lever 35, and the seal cam. This is performed with the release lever 43. Therefore, the phase alignment at the time of connection, which is indispensable when disconnecting and connecting the drive force transmission system at the time of attaching and detaching the draw-out unit using gears that mesh with each other, is unnecessary, and the draw-out unit 47 can be easily mounted. . In the above embodiment, the drawer unit 4
7 is pulled out and mounted, the composite cam 50 has a slight gap as described above with respect to the tip portions 37a and 45a of the blade release lever 35 and the seal release lever 43, so that they may interfere with each other. None at all, so
Furthermore, the loading becomes easier.

B. Second Embodiment Next, referring to FIG. 5 and FIG. 6, the second embodiment of the second invention
An example will be described. In the second embodiment, only the blade cam 51 of the composite cam 50 is different from the first embodiment, so the description will focus on this difference, and the same parts as in the first embodiment are the same. And the description thereof will be omitted.

(3) Configuration of the Second Embodiment In the contact portion of the blade cam 51 with the blade release lever 35, that is, the cam surface 51a, a position of about 60 degrees on the rear side in the rotational direction from the starting point and about 300. Convex portions 55 that project outward in the radial direction are respectively formed at the positions of degrees. With this configuration, when the cam surface 51a passes by the rotation of the blade cam 51, the convex portion 55 suddenly reciprocates the tip portion 37a of the blade release lever 35 that comes into contact with the convex portion 55 to impact the blade 28. give.

(4) Operation of the Second Embodiment Similar to the first embodiment, the composite cam 50 is placed at the starting point P at the 9 o'clock position in FIG. 5 and stopped, and the blade body 34 is attached to the photosensitive drum 10. The blade body 3 in the pressed state
By 4, the toner remaining on the photoconductor drum 10 is scraped off. After cleaning in this manner, the composite cam 50 is rotated again at a predetermined timing by a drive motor (not shown). Then, the sealing cam 52 having the cam surface 52a whose height does not change from the start of rotation to 60 ° rotates ahead of the cam surface 51a whose height becomes high while keeping the sealing release lever 43 in the same state. The cam surface 51a of the blade cam 51 that it has comes into contact with the tip portion 37a of the blade release lever 35 to swing it.

When the blade main body 34 is separated from the photosensitive drum 10 which has been rotated by about 60 degrees and completed cleaning, the tip end portion 3 of the blade release lever 35 is released.
7a is rapidly reciprocated along the convex portion 55. This gives an impact to the blade body 34, so that the toner attached to the tip of the blade body 34 drops due to this impact. Further, the composite cam 50 continues to rotate, and when it rotates 90 degrees, the blade main body 34 is separated from the photosensitive drum 10 by the maximum distance, and when the composite cam 50 is rotated up to nearly 180 degrees, the seal main body 42 moves. After that, the end point Q is placed at the 9 o'clock position in FIG. 5 and stopped.

For cleaning, the composite cam 50
Even when the end point Q rotates from the 9 o'clock position to the start point P at the 9 o'clock position, at a time after the seal body 42 is pressed against the photosensitive drum 10 and before the blade body 34 is pressed against the photosensitive drum 10. , The tip portion 37a of the blade release lever 35
Is rapidly reciprocated along the convex portion 55. As a result, the blade body 34 is again impacted, and the toner attached to the tip of the blade body 34 drops.

According to the image forming apparatus of the second embodiment described above, the same effect as that of the first embodiment can be obtained, and the convex portion 55 formed on the cam surface 51a of the blade cam 51 is provided. However, in a state where the blade body 34 is separated from the photoconductor drum 10, by impacting the blade body 34 via the blade release lever 35, the toner attached to the tip of the blade body 34 is surely removed. be able to. Moreover, since it can be realized with a simple structure in which the convex portion 55 is provided on the blade cam 51, it is inexpensive and space-saving, and no impact noise is generated.

(3) Modification Example As shown in FIG. 6, the convex portion 55 serves as an impact generating means.
Alternatively, the blade 28 can be impacted by forming a recess 56 that is recessed radially inward.
Further, the impact generating means 55, 56 may be provided at least at one place, but if a plurality of places are provided as described above, the toner removing effect can be enhanced. Furthermore, the configuration of the second embodiment as described above can also be applied to the cleaning device 24 that does not include the sealing mechanism 29 and the sealing cam 52.

In addition, the first and second embodiments have been described by taking as an example an image forming apparatus of the type in which different types of toner images are superposed on the photosensitive drum 10 described above, but the present invention is not limited to this. For example, the present invention can be applied to other image forming apparatuses in which an intermediate transfer body is provided between the photoconductor drum 10 and a sheet, and different types of toner images are once superposed on the intermediate transfer body and are collectively transferred to the sheet. However, in this case, the present invention is applied to the cleaning device for the intermediate transfer member, not the cleaning device for the photosensitive drum 10 as described above. Also, the blade 28
Although the doctor blade method has been described as an example, it is also applicable to the wiper blade method. Furthermore, although the photoconductor drum 10 has been described as an example of the image carrier, the present invention can be applied to a photoconductor belt.

[0051]

As described above in detail, according to the image forming apparatus of the first aspect of the present invention, the toner receiving member cam is provided by the toner receiving member cam via the cam follower capable of contacting the cam. Is pressed against the image bearing member in advance, and then the blade cam is pressed against the image bearing member via a cam follower capable of contacting the blade cam to scrape off the residual toner on the image bearing member with this blade. The toner receiving member receives the scraped residual toner. And
After scraping off, the blade cam separates the blade from the image carrier, and after this, the toner receiver cam separates the toner receiver from the image carrier. As described above, the above operation can be realized with a simple configuration of the cam for the blade and the cam follower, the cam for the toner receiving member, and the cam follower capable of contacting the cam for the toner receiving member, and a considerable space is required for the arrangement. In addition, the structure can be significantly downsized and simplified as compared with the case where an expensive solenoid is used, and the manufacturing cost can be reduced.

According to the image forming apparatus of the fourth aspect of the present invention, in the state where the blade is separated from the image carrier, the impact generating means is formed on the blade cam in a convex or concave shape. Since it is configured to give an impact to the blade via the cam follower, the toner attached to the blade can be reliably dropped and removed from the blade with an extremely simple configuration.

[Brief description of drawings]

FIG. 1 is a side sectional view schematically showing an overall configuration of an image forming apparatus of a first embodiment according to the first invention.

FIG. 2 is a side sectional view schematically showing a cleaning device and a photosensitive drum of the image forming apparatus of the first embodiment according to the first invention.

3 is a cross-sectional arrow view taken along the line AA shown in FIG.

4 is a cross-sectional arrow view taken along the line BB shown in FIG.

FIG. 5 is a cross-sectional view taken along the line corresponding to the line BB shown in FIG. 3 of the image forming apparatus according to the second exemplary embodiment of the present invention.

FIG. 6 is a diagram showing another example of the blade cam of the image forming apparatus of the second embodiment according to the second invention.

[Explanation of symbols]

10 ... Photosensitive drum (image bearing member), 28 ... Blade 29
... Sealing mechanism (toner receiving member), 35 ... Blade release lever (cam follower), 43 ... Seal release lever (cam follower), 47 ... Drawout unit, 48 ... Image processing apparatus main body, 50 ... Compound cam, 51 ... Blade cam,
52 ... Sealing cam (receiving member cam), 55 ... Convex portion (impact generating means), 56 ... Recessed portion (impact generating means).

Front Page Continuation (72) Inventor Kazunori Numao 2274 Hongo, Ebina City, Kanagawa Prefecture Fuji Xerox Co., Ltd.

Claims (4)

[Claims] 1. A cam follower, which is swingable so as to come into contact with and separate from an image bearing member, scrapes off toner remaining on the image bearing member by the movement of the image bearing member at the time of pressure contact, and swings integrally. A toner receiving member that is configured to be swingable so as to come into pressure contact with and separate from the image carrier and to receive the toner scraped off by the blade at the time of pressure contact, and a cam follower that integrally swings. A blade contactable with the cam follower of the blade, when the residual toner is scraped off, the blade is brought into pressure contact with the image carrier through the cam follower, and is shaken so as to be separated from the image carrier after the scraping. The blade cam to be moved and the cam follower of the toner receiving member can be brought into contact with each other, and the toner receiving member is moved through the cam follower. And a cam for the toner receiving member that is pressed against the image carrier prior to the card and oscillates so as to move away from the image carrier after the blade. . 2. The image forming apparatus according to claim 1, wherein the blade cam and the toner receiving member cam are integrated cams. 3. The blade and the toner receiving member are provided in a drawing unit that can be drawn out from the apparatus main body, and the blade cam and the toner receiving member cam are
The image forming apparatus according to claim 1, wherein the image forming apparatus is provided in the apparatus main body. 4. A cam follower which is swingable so as to come into pressure contact with and separate from an image carrier, scrapes off toner remaining on the image carrier during the pressure contact by the movement of the image carrier, and swings integrally. A blade that is provided and is capable of contacting the cam follower.When scraping off residual toner, the blade is brought into pressure contact with the image carrier via the cam follower, and after scraping away from the image carrier. And a cam for the blade that is swung so that the blade comes into contact with the cam follower in a state in which the blade is separated from the image bearing member. An image forming apparatus comprising: an impact generating unit that sometimes impacts the blade.