JP2005326768A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus where a filming material formed on an image carrier is removed even in processing a job of many copies with inexpensive constitution. <P>SOLUTION: The image forming apparatus has the image carrier 6 for carrying a toner image, a cleaning device 9 for recovering toner remaining on the image carrier after the toner image is transferred to a transfer medium, and a grinding device 100 for removing the filming material on the surface of the image carrier. In the image forming apparatus, the grinding device 100 is constituted of a grinding means 130, a rocking lever 110, and a one-way clutch 120. Then, the image carrier 6 is moved between a working position and a standby position by a switching means. The rocking lever 110 is rocked according as the image carrier is moved between the working position and the standby position, and the grinding means 130 is rotated little by little by the one-way clutch 120 only at the time of rocking in one direction. Thus, the grinding means 130 changes its contact part with the image carrier 6 and maintains grinding ability. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus provided with a cleaning device for removing a filming material formed on an image carrier such as a photosensitive member or an intermediate transfer member.

  A color image forming apparatus generally forms an image as follows. First, an electrostatic latent image is formed by irradiating an original image on a drum-shaped photoreceptor surface provided for each color of Y, M, C, and K and uniformly charged. When the photosensitive member rotates and this electrostatic latent image reaches the developing device for each color of Y, M, C, and K, it is developed with toner and visualized. After the toner images for each color of Y, M, C, and K are transferred onto the intermediate transfer member, the toner images are transferred from the intermediate transfer member to a transfer sheet as a transfer medium, and the color toner on the transfer sheet is transferred. A color image is formed by fixing the image by melting it with a fixing device.

  The intermediate transfer member has an endless belt shape and is wound between a plurality of rollers including a belt driving roller and a tension roller. A color toner image is repeatedly formed on the intermediate transfer member, but a small amount of toner remaining on the intermediate transfer member after transfer is removed by a cleaning device. This cleaning device includes a cleaning blade and a cleaning roller.

  However, when fine toner or toner wax dissolved by heat, pressure, or the like is generated on the photosensitive member or intermediate transfer member, it cannot be completely removed by the blade or roller in the blade cleaning method, and gradually forms a filming product. This filming product has poor toner adhesion, and a white portion appears in the image.

  In particular, in the case of the double transfer method using an intermediate transfer member, the transfer efficiency is greatly reduced by the generation of a slight filming product. Further, when a filming material is formed on the image carrier, the friction coefficient between the blade and the image carrier increases, and therefore, the blade is likely to be caught when the counter blade system is used. Further, when the image carrier is a belt member stretched between a driving roller and a driven roller, the driving roller is idled due to an increase in frictional force between the blade and the image carrier.

  As a solution to this problem, Japanese Patent Application Laid-Open No. 5-273893 proposes an image forming apparatus provided with a rubbing member (filming removal brush) for polishing the surface of an image carrier. . This is because a sliding member is provided so as to be able to come into contact with and separate from the image carrier by a solenoid, and when the filming material is formed by detecting the formation of the filming material on the image carrier using the light emitting element and the light receiving element, The rubbing member is rotated by a motor and pressed against the image carrier by a solenoid to remove the film.

JP-A-5-273893 FIG. 1, claim 1, paragraph 0013

  However, the polishing apparatus described in Patent Document 1 uses an expensive motor, a light emitting element, and a light receiving element.

  An object of the present invention is to provide an image forming apparatus including a polishing apparatus that can remove a filming product formed on an image carrier with an inexpensive configuration.

  In order to achieve the above object, an image forming apparatus according to claim 1 of the present application includes an image carrier that carries a toner image, and remains on the image carrier after the toner image is transferred onto a transfer medium. In an image forming apparatus having a cleaning device for collecting toner and a polishing device for removing filming material on the surface of the image carrier, the polishing device comprises a polishing means and an intermittent drive means for the polishing means, The intermittent driving means is driven by the image carrier.

  In the image forming apparatus according to claim 2 of the present application, the intermittent driving means includes a swing lever and a one-way clutch provided on a swing shaft of the swing lever, and the image carrier is in an operating position. There is provided switching means for displacing the rotation position of the rocking lever with respect to the standby position, and the rocking lever is rocked by the operation of the switching means, and the one-way clutch intermittently turns the polishing means to 1 by the rocking. It is characterized by rotating in the direction.

  The image forming apparatus according to claim 3 of the present application is characterized in that the polishing means is an endless belt and is wound between a roller on the swing shaft and a roller on the tip side of the swing lever. It is said.

  An image forming apparatus according to claim 4 of the present application is an image carrier belt in which the image carrier is wound around a plurality of rollers, and at least one of the plurality of rollers is moved to an operating position by the operation of the switching means. It is characterized in that it moves between the standby positions, the trajectory of the image carrier belt is changed by the movement, and the swing lever is swung by the change of the trajectory.

  The image forming apparatus according to claim 5 of the present application is characterized in that the roller that moves between the operating position and the standby position is a tension roller.

  The image forming apparatus according to claim 6 of the present application is characterized in that the switching means includes a cam.

  The image forming apparatus according to claim 7 of the present application is characterized in that the swing lever includes a weight in the vicinity of the tip, and the polishing means is constantly pressed against the image carrier by the weight.

  The image forming apparatus according to claim 8 of the present application is characterized in that the image carrier belt is an intermediate transfer belt.

  The image forming apparatus according to claim 9 of the present application is characterized in that the image carrier belt is a photosensitive belt.

  The image forming apparatus according to claim 10 of the present application is characterized in that the image carrier belt is a transfer belt for a transfer medium.

According to the above means, the following operation can be obtained.
Toner remaining on the image carrier after transfer to a transfer medium such as transfer paper is removed by the cleaning roller and the cleaning blade of the cleaning device, but a trace amount of toner and wax that cannot be removed by these remains on the image carrier. These solidify on the image carrier to form a filming product. The filming product is removed by polishing the polishing means of the polishing apparatus in contact with the image carrier.

  However, if the same part of the polishing means is in contact with the image carrier for a long time, the polishing ability gradually decreases. Therefore, the polishing apparatus is intermittently driven by the image carrier to prevent the polishing power from being lowered by shifting the contact portion of the abrasive.

  The intermittent drive means comprises a swing lever and a one-way clutch, and the switching means moves the image carrier between the operating position and the standby position. The swing lever swings according to the movement between the operating position and the standby position of the image carrier, and the polishing means is rotated little by little only when one swing is performed by the one-way clutch. As a result, the polishing means changes the contact portion with the image carrier and maintains the polishing ability.

  According to the present invention, since the intermittent drive means is driven by the image carrier, a motor is not necessary. In addition, since the polishing means is intermittently rotated, a light emitting element and a light receiving element are not required, the mechanism can be simplified, and an excellent polishing apparatus can be obtained.

  If the polishing means is an endless belt, a large polishing surface can be secured as compared with the polishing roller, and it can be used for a long time.

  If the image carrier is an image carrier belt and at least one roller is moved between the operating position and the standby position by the operation of the switching means, the movement causes the swing lever to swing and the one-way clutch. The polishing means can be rotated intermittently.

  The roller that moves between the operating position and the standby position diverts the tension roller, thereby eliminating the need for special parts.

  When a weight is provided on the swing lever, the polishing means can be pressed against the image carrier with a desired pressure contact force, and an appropriate polishing pressure can be obtained.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a configuration of a color image forming apparatus provided with a polishing apparatus of the present invention. As shown in FIG. 1, the color image forming apparatus is called a tandem type color image forming apparatus, and includes an automatic document feeder 30, an image reading device 60, image writing devices 3Y, 3M, 3C, 3K, and a photoreceptor 1Y. , 1M, 1C, 1K, charging devices 2Y, 2M, 2C, 2K, developing devices 4Y, 4M, 4C, 4K, fixing device 24, image carrier 6 comprising an intermediate transfer belt, paper feed cassettes 20a, 20b, 20c, A conveyance system 22 and the like are included.

  5Y, 5M, 5C, and 5K are toner replenishing units that replenish new toner to the developing devices 4Y, 4M, 4C, and 4K, respectively.

  The automatic document conveying means 30 is means for automatically conveying a double-sided or single-sided original d. The image reading device 60 is a device that reads image information by a scanning optical system. The image reading device 60 reflects the contents of a large number of originals d fed from the original placement table by three movable mirrors 60c, and collects the condensing lens 60b. Thus, an image is formed on the image sensor 60a made of a CCD and read.

  The image forming unit 10Y that forms a yellow image includes a charging device 2Y, an image writing device 3Y, a developing device 4Y, and a cleaning device 8Y that are disposed around a photoreceptor 1Y as an image carrier. The image forming unit 10M that forms a magenta image includes a photoreceptor 1M as an image carrier, a charging device 2M, an image writing device 3M, a developing device 4M, and a cleaning device 8M. The image forming unit 10C that forms a cyan image includes a photoreceptor 1C as an image carrier, a charging device 2C, an image writing device 3C, a developing device 4C, and a cleaning device 8C. The image forming unit 10K that forms a black image includes a photoreceptor 1K as an image carrier, a charging device 2K, an image writing device 3K, a developing device 4K, and a cleaning device 8K. The charging device 2Y and the image writing device 3Y, the charging device 2M and the image writing device 3M, the charging device 2C and the image writing device 3C, and the charging device 2K and the image writing device 3K constitute a latent image forming unit.

  The image carrier 6 as an intermediate transfer belt is an endless belt, is stretched by a plurality of rollers, and is rotatably supported. The image carrier 6 is provided with a cleaning device 9. The cleaning device 9 includes a cleaning roller and a cleaning blade.

  A signal of image information formed on the image sensor 60a is sent to an image processing unit (not shown). The image processing unit performs analog processing, A / D conversion, shading correction, image compression processing, and the like, and then sends a signal for each color to the image writing devices 3Y, 3M, 3C, and 3K.

  In the image writing apparatuses 3Y, 3M, 3C, and 3K, a semiconductor laser is used as a laser light source, and a light beam emitted from the semiconductor laser is formed into a scanning light beam by an optical element such as a polygon mirror to be used as a photosensitive body as a scanning object. It enters the bodies 1Y, 1M, 1C, and 1K, and forms an electrostatic latent image of each color.

  The respective color images formed by the image forming units 10Y, 10M, 10C, and 10K are sequentially transferred onto the rotating image carrier 6 by transfer devices 7Y, 7M, 7C, and 7K as primary transfer devices (1). Next transfer), a synthesized color image is formed. The recording paper P accommodated in the paper feed cassettes 20a, 20b, and 20c is fed by the paper feed means 21a, 21b, and 21c, passes through the transport system 22, and is timed by the registration roller 23 as a secondary transfer device. The color image is transferred onto the recording paper P (secondary transfer). The recording paper P onto which the color image has been transferred is fixed by the fixing device 24, is sandwiched between the paper discharge rollers 25, and is placed on a paper discharge tray 26 outside the apparatus.

  On the other hand, after the color image is transferred onto the recording paper P by the transfer device 7a, the image carrier 6 from which the recording paper P has been separated is cleaned by the cleaning device 9, and the filming material is polished by the polishing device 100.

  FIG. 2 is an enlarged view of the image carrier 6 and the polishing apparatus 100 shown in FIG. FIG. 3 is the same view as FIG. 2 and shows a standby state.

  As shown in these drawings, the image carrier 6 is an endless belt and is wound around a driving roller 6a, a tension roller 6b, a roller 6c, and a roller 6d facing the transfer device 7a. A driving force from a motor (not shown) is transmitted to the driving roller 6a, and the image carrier 6 rotates in the clockwise direction in the figure. The tension roller 6b is urged upward in the figure by an elastic body (not shown).

  The image carrier 6 includes transfer devices 7Y, 7M, 7C, and 7K that come into contact with and separate from the photoconductors 1Y, 1M, 1C, and 1K. Of these, the transfer devices 7Y, 7M, and 7C are integrally connected by a connecting plate 7. doing. A cam 7b is provided at the lower end of the connecting plate 7, and the cam 7b is rotatable by a shaft 7d. That is, the switching means is constituted by the cam 7b, the shaft 7d, and a solenoid or motor (not shown) that rotates the shaft 7d. When the cam 7b is rotated to the position shown in FIG. 2, the connecting plate 7 is moved up to the uppermost position, and the transfer devices 7Y, 7M, and 7C are lifted all at once to come into contact with the photoconductors 1Y, 1M, and 1C. 6 goes into operation. When the cam 7b is rotated 90 ° clockwise to the position shown in FIG. 3, the connecting plate 7 is lowered to the lowest position, the transfer devices 7Y, 7M, and 7C are lowered and separated from the photoreceptors 1Y, 1M, and 1C, and the image The carrier 6 enters a standby state. Since the image carrier 6 is loosened in the standby state, the tension roller 6b is lifted to almost the same height as the drive roller 6a and applies tension so that the image carrier 6 does not loosen.

  The cleaning device 9 is the same as the conventional cleaning device, and includes a cleaning roller 9a and a cleaning blade 9b.

  The above is the same as the conventional image forming apparatus. The present invention is characterized by a polishing apparatus 100 that removes the filming material on the image carrier 6. The polishing apparatus 100 will be described below.

  4 is an exploded perspective view of the polishing apparatus 100, FIG. 5 is an assembly view of the polishing apparatus 100, and FIG. 6 is a perspective view of the swing lever 110.

  As shown in these drawings, the polishing apparatus 100 includes a left and right swing lever 110, a one-way clutch 120, an endless belt-shaped polishing means 130, and rollers 140 and 150 provided at both ends of the swing lever 110. And a weight 160 composed of two rollers, a mounting arm 170, and an E-ring 175.

  On the surface of the polishing means 130, an abrasive that can scrape off the filming material formed on the surface of the image carrier 6 is applied. Further, the width of the polishing means 130 has a width that can cover at least the image forming area of the image carrier 6, and is substantially the same as the width of the image carrier 6 in the embodiment.

  The swing lever 110 has a through hole 111 at one end, and a one-way clutch 120 is attached thereto. The one-way clutch 120 fixes the shaft 141 of the roller 140 to the inner diameter 121 thereof. The shaft 141 and the roller 140 have an integral structure. The center of the roller 140 is the swing axis a. There are three through holes on the distal end side of the swing lever 110, and the shaft portions at the distal ends of the roller 150 and the two weights 160 are fitted to each other. The rollers 150 and the weight 160 may be rotatable with respect to the swing lever 110 or may be fixed. The mounting arm 170 has a through-hole 171, and the through-hole 171 and the through-hole 111 of the swing lever 110 are overlapped to be coupled in a rotatable state by an appropriate method. For example, the length in the axial direction of the one-way clutch 120 may be increased and fitted with the through hole 171 of the mounting arm 170 together with the through hole 111 of the swing lever 110.

  One of the swing levers 110 and the mounting arm 170 is coupled, and the rollers 140 and 150 and the weight 160 are attached to this, and the state shown in FIG. 4 is obtained. The polishing means 130 is attached thereto, and the rollers 140 and 150 protruding from the front side of the polishing means 130 and the tip small diameter portion of the weight 160 are attached to the swing lever 110 and the mounting arm 170 on the opposite side, and the one-way clutch. When 120 is fitted and assembled in the state of FIG. 5, an E-ring 175 is attached to prevent it from coming off. The roller 140 is a driving roller for the polishing means 130 and the roller 150 is a driven roller.

  The mounting arm 170 has a bearing recess 172 and a recess 173 on both sides of the through hole 171. The bearing recess 172 is fitted to a shaft 9 c provided in the cleaning device 9 and holds the polishing device 100 at a predetermined position of the image carrier 6. A tension roller 180 is inserted into the recess 173. When the tension roller 180 applies an appropriate tension to the polishing means 130 and the roller 140 rotates, the polishing means 130 also rotates together.

  FIG. 7 is a schematic diagram for explaining the movement of the polishing apparatus 100 of the present invention. In the figure, the solid line indicates the state when the image carrier 6 is in operation, and the virtual line 6 ′ indicates the state during standby. When the cam 7b is in the rotational position shown in FIG. 2, a tension is applied to the image carrier 6, and the tension roller 6b is pulled downward in the figure and comes to the position shown by the solid line in FIG.

  The polishing means 130 is always in contact with the image carrier 6 because the swing lever 110 has a cantilever structure and has a weight 160. However, the image carrier 6 is in contact with the lowering of the tension roller 6b. Accordingly, the polishing means 130 also descends accordingly. Since the swing lever 110 is integral with the polishing means 130, the tip end side is lowered with the one-way clutch 120 as the center. In this state, since a color image is formed, the driving roller 6a rotates in the clockwise direction, and the image carrier 6 also rotates in the clockwise direction indicated by the arrow. The polishing means 130 is always in contact with the image carrier 6 while the job is being performed, and the surface thereof is polished to remove the filming material.

  When the job is completed, the cam 7b of the switching means rotates 90 ° clockwise, and the image carrier 6 enters the standby state shown in FIG. At this time, the trajectory of the image carrier 6 changes as indicated by an imaginary line 6 'in FIG. That is, the tension roller 6b rises to the position 6b 'indicated by the phantom line. Since the rocking lever 110 has the weight 160, it is always received from below by the image carrier 6. However, when the tension roller 6b moves to the position 6b ′, the rocking lever 110 also moves from the rotation position indicated by the solid line. The center of the one-way clutch 120 is rotated around the rotation position of 110 ′ indicated by the phantom line. At this time, the one-way clutch 120 rotates idly without transmitting the rotation to the roller 140.

  When the next job is started, the cam 7b rotates 90 ° counterclockwise, and the image carrier 6 is in the operating state shown in FIG. As a result, the tension roller 6b is lowered from the position of the phantom line 6 'in FIG. 7 to the position of the solid line 6, and the swing lever 110 is also rotated in the clockwise direction from the imaginary line 110' to the rotation position of the solid line 110. At this time, the one-way clutch 120 transmits the rotation of the swing lever 110 to the roller 140. Since an appropriate tension is applied to the polishing means 130 by the tension roller 180, the rotation of the roller 140 is transmitted to the polishing means 130 as it is, and the polishing means 130 rotates only slightly. As a result, the part of the polishing means 130 that has been in contact with the image carrier 6 moves, and the new part comes into contact with the image carrier 6. Therefore, it is possible to prevent the polishing ability from being reduced due to the contact of the same part by rotating the polishing means 130 intermittently. Thereafter, each time a new job is started, the polishing means 130 rotates slightly, and the contact portion is shifted for each job to contact the image carrier 6.

  In this embodiment, the one-way clutch transmits rotation to the polishing means 130 during standby → operation, but conversely, rotation may be transmitted during operation → standby.

  As can be seen from the above description, the swing lever 110 and the one-way clutch 120 constitute an intermittent drive means of the polishing apparatus 100 and are driven by the movement of the image carrier 6.

  Since the present invention is configured as described above, it is not necessary to use an expensive motor. In addition, the configuration is simple and inexpensive.

  In the above embodiment, an endless belt is exemplified as the polishing means 130, but the roller 140 can also be used as a polishing roller.

  Further, as a method of swinging the swing lever 110, in the above-described embodiment, the locus of the intermediate transfer belt is changed. However, it is not limited to this configuration. For example, even if a protrusion or the like is provided at one position of the image carrier 6 and is rocked every time it passes through the rocking lever, it can be driven intermittently. Although the intermediate transfer belt is exemplified as the image carrier 6, the image carrier 6 can be similarly applied to the photosensitive belt. Even a drum-type photoreceptor can be applied by changing the distance between the polishing apparatus at the operating position and the standby position, or by providing a protrusion and swinging the swing lever with this protrusion. is there. Furthermore, the present invention can also be applied to a belt that conveys a transfer medium such as transfer paper.

It is a figure which shows the structure of the color image forming apparatus provided with the grinding | polishing apparatus of this invention. FIG. 2 is an enlarged view of a part of the image carrier and the polishing apparatus in FIG. FIG. 2 is an enlarged view of the image carrier and the polishing apparatus in FIG. 1, and shows a standby state. It is a disassembled perspective view of a grinding | polishing apparatus. It is an assembly drawing of a grinding | polishing apparatus. It is a perspective view of a rocking lever. It is a mimetic diagram explaining movement of a polish device of the present invention.

Explanation of symbols

a Oscillating shaft 6 Image carrier 6b Tension roller 7b Cam (switching means)
7d Shaft 9 Cleaning device 100 Polishing device 110 Swing lever 120 One-way clutch 130 Polishing means 160 Weight

Claims (10)

An image carrier that carries a toner image, a cleaning device that collects toner remaining on the image carrier after the toner image is transferred onto a transfer medium, and a filming material on the surface of the image carrier. In an image forming apparatus having a polishing apparatus,
The image forming apparatus, wherein the polishing apparatus includes a polishing unit and an intermittent driving unit of the polishing unit, and the intermittent driving unit is driven by the image carrier.   The intermittent driving means includes a swing lever and a one-way clutch provided on a swing shaft of the swing lever, and the image carrier is configured to change a rotational position of the swing lever between an operating position and a standby position. 2. A switching means for displacing is provided, and the rocking lever is swung by operation of the switching means, and the one-way clutch intermittently rotates the polishing means in one direction by the rocking. The image forming apparatus described.   The image forming apparatus according to claim 2, wherein the polishing unit is an endless belt and is wound between a roller on the swing shaft and a roller on a tip side of the swing lever.   An image carrier belt in which the image carrier is wound around a plurality of rollers, and at least one of the plurality of rollers is moved between an operating position and a standby position by the operation of the switching means, 4. The image forming apparatus according to claim 2, wherein a trajectory of the image carrier belt is changed, and the swing lever is swung according to the change of the trajectory.   The image forming apparatus according to claim 4, wherein the roller that moves between the operating position and the standby position is a tension roller.   6. The image forming apparatus according to claim 2, wherein the switching unit includes a cam.   7. The image forming apparatus according to claim 2, wherein the swing lever includes a weight in the vicinity of a tip, and the polishing means is constantly pressed against the image carrier by the weight.   6. The image forming apparatus according to claim 4, wherein the image carrier belt is an intermediate transfer belt.   6. The image forming apparatus according to claim 4, wherein the image carrier belt is a photosensitive belt.   6. The image forming apparatus according to claim 4, wherein the image carrier belt is a transfer belt for a transfer medium.

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