JP7378955B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus that includes an image forming control board that controls an image forming unit, and a paper transport control board that controls a paper transport unit.

Generally, an image forming apparatus includes a housing, a drive unit that drives an image forming section provided in the housing, and an electrical board (control board) that includes a power supply board and a controller board for controlling the drive unit. ing. Normally, the control board is integrated into one board, and together with the drive unit, is arranged side by side on the outer surface of the rear plate at the rear of the housing, and is housed in an enclosure.

JP2015-087627A

However, in recent years, in high-productivity, high-speed image forming apparatuses, the number of loads to be driven, including FANs, motors, sensors, and sensors for monitoring the loads has increased. For this reason, it is not possible to mount all the control circuits on one control board, and a plurality of divided control boards are used. For example, in an image forming apparatus that uses multiple control boards, if a photoreceptor becomes unable to drive, it can be immediately determined whether the problem is with the photoreceptor drive unit or with one of the multiple control boards. There is a problem that it is difficult to judge and the downtime becomes long.

The present invention provides an image forming apparatus that can reduce downtime as much as possible even when a drive member becomes unable to drive and it is not clear whether the problem is with the drive unit or the control unit that controls the drive unit. The purpose is to provide

In order to solve the above problem, an image forming apparatus according to a first aspect of the present invention includes a photosensitive drum, an image forming means for forming an image on the photosensitive drum and transferring the image to a recording material, and an image forming means for forming an image on the photosensitive drum and transferring the image to a recording material; a drum motor that drives the body drum; a first support member that supports the drum motor; a first control board that controls driving of the drum motor; a conveyance roller that conveys the recording material; and a conveyance roller that drives the conveyance roller. a second support member that supports the transport motor; and a second control board that controls the transport motor, and the first control board is attached to the first support member. , the second control board is attached to the second support member.

According to the present invention , the driving means and the control board for controlling the driving means can be integrally replaced together with the support member .

1 is a vertical cross-sectional view showing a schematic configuration of an image forming apparatus according to an embodiment. 2 is a block diagram showing a control configuration of the image forming apparatus shown in FIG. 1. FIG. 2 is a rear view showing the positional relationship between each component and a control board that controls the component in the image forming apparatus of FIG. 1. FIG.

Hereinafter, embodiments will be described in detail with reference to the drawings.

FIG. 1 is a vertical cross-sectional view showing a schematic configuration of an image forming apparatus according to an embodiment.

In FIG. 1, an image forming apparatus 100 includes a document reading apparatus 120 and a user interface (UI) 126 for a user to operate the image forming apparatus 100. The image forming apparatus 100 is an electrophotographic full-color apparatus, and includes four process cartridges 103Y, 103M, 103C, and 103K as image forming members. The process cartridges 103Y to 103K are arranged substantially horizontally at regular intervals, and form yellow, magenta, cyan, and black images, respectively. The process cartridges 103Y to 103K have the same configuration, and are configured to be removably attached to the main body of the apparatus.

The process cartridges 103Y-K include drum-shaped electrophotographic photoreceptors (hereinafter referred to as "photoreceptor drums") 104Y-K as image carriers. The photoreceptor drums 104Y to 104K are negatively charged OPC photoreceptors, and are provided with a photoconductive layer on a drum base made of aluminum. The photosensitive drums 104Y to 104K are rotationally driven at a predetermined process speed by a drive device (not shown) which will be described later.

A primary charger 109 (Y-K), a developing device 105 (Y-K), and a drum cleaner 112 (Y-K) are arranged around the photoreceptor drums 104Y-K, respectively. A laser scanner unit 108 having a laser exposure section corresponding to each of the photoreceptor drums 104Y-K is arranged below between the primary charger 109 (Y-K) and the developing device 105 (Y-K).

The primary chargers 109 (Y-K) charge the surfaces of the corresponding photosensitive drums 104Y-K to a predetermined negative potential using a charging bias applied from a charging bias power source (not shown).

The laser scanner unit 108 is a laser emitting unit that emits laser light corresponding to time-series electric digital pixel signals of given image information. The laser scanner unit 108 irradiates laser light from each laser exposure section to expose the corresponding photoreceptor drums 104Y to 104K, thereby forming an electrostatic latent image on the surface of each of the photoreceptor drums 104Y to 104K in accordance with image information. form.

The developing devices 105 (Y to K) contain toner as a developer, and supply the toner to the electrostatic latent images formed on the photoreceptor drums 104 to visualize them as toner images. Toner bottles (containers) 130Y, 130M, 130C, and 130K are arranged to correspond to the developing devices 105 (Y to K). The toner bottles 130Y to 130K are configured to be removably attached to the image forming apparatus 100, respectively, and contain toner of a predetermined color to be supplied to the corresponding developing device 105 (Y to K). are supplied to the respective developing devices 105 (Y to K).

The drum cleaners 112 (Y to K) are equipped with cleaning blades. The drum cleaners 112 (Y to K) clean transfer residual toner remaining on the photoconductor drums 104Y to 104K when the toner images formed on the photoconductor drums 104Y to 104K are transferred to the intermediate transfer belt 101 described later. Collect.

An endless intermediate transfer belt 101 is arranged above each of the process cartridges 103Y to 103K, and rotates in contact with each of the photoreceptor drums 104Y to 104K. An intermediate transfer belt unit 115 is configured by the intermediate transfer belt 101 and its peripheral members. Primary transfer rollers 114 (Y to K) are arranged at positions that contact each of the photoreceptor drums 104Y to 104K via the intermediate transfer belt 101, respectively. That is, the primary transfer rollers 114 (Y to K) are arranged inside the intermediate transfer belt 101 so as to face each of the photoreceptor drums 104Y to K via the intermediate transfer belt 101, and They are configured to be biased toward each other. The primary transfer rollers 114 (Y to K) function as primary transfer means.

The intermediate transfer belt 101 is stretched between a drive roller 116 and a driven roller, and is rotationally driven by a drive gear on the main body of the apparatus (not shown). The drive roller 116 is a secondary transfer opposing roller, and is in contact with the secondary transfer roller 117 via the intermediate transfer belt 101. The nip portion where the drive roller 116 and the secondary transfer roller 117 come into contact becomes the secondary transfer portion Te. A transfer belt cleaner 107 is arranged to face the driven roller with the intermediate transfer belt 101 in between.

Further, an optical sensor 140 is arranged to face the belt surface of the intermediate transfer belt 101. The optical sensor 140 reads a toner patch for density detection or color misregistration correction formed on the intermediate transfer belt 101 on the upstream side in the rotational direction of the intermediate transfer belt 101 than the secondary transfer portion Te.

A paper feed cassette 121 and a manual feed tray 122 are arranged below the laser scanner unit 108. The paper feed cassette 121 and the manual feed tray 122 accommodate paper P as a recording material. The paper P is transported through a paper transport path 145 to a secondary transfer section Te, a fixing unit 400 (described later), and a paper output tray 125. The paper transport path 145 is a vertical path transport path that transports the paper P substantially vertically from below to above. The paper transport path 145 includes a transport roller as a transport member, and examples of the transport roller include a paper feed roller 135, a pull-out roller 136, a registration roller (registration roller) 123, and a paper discharge roller 124.

A fixing unit 400 is arranged downstream of the secondary transfer section Te in the paper transport path 145 in the paper transport direction. The fixing unit 400 includes a fixing roller 118 and a pressure roller 119, and fixes the transferred image on the paper P, and forms part of a vertical path transport path that transports the paper P in the vertical direction.

Next, a control configuration of the image forming apparatus shown in FIG. 1 will be explained.

FIG. 2 is a block diagram showing a control configuration of the image forming apparatus shown in FIG. In FIG. 2, the image forming apparatus 100 includes an image forming control board 200 and a paper conveyance control board 600 as control components. The image formation control board 200 functions as a control unit that controls the constituent members for image formation, and the paper conveyance control board 600 functions as a control unit that controls the constituent members for paper conveyance. The image forming control board 200 and the paper transport control board 600 are equipped with control circuits for image formation and paper transport, respectively.

The image forming control board 200 includes a CPU 201a, a ROM 201b, and a RAM 201c. Further, the image forming control board 200 has a built-in mechanical load control section A208. The CPU 201a is connected to the ROM 201b, the RAM 201c, and the mechanical load control unit A208 via an address bus or a data bus, respectively. The CPU 201a is also connected to a user interface (UI) 126 and a high voltage control section 501 of the high voltage unit 500 via an address bus or a data bus, respectively. Further, the CPU 201a is also connected to the heater 401 of the fixing unit 400 and the mechanical load control section B608 of the sheet conveyance control board 600, respectively, by an address bus or a data bus. The mechanical load control unit A208 is also connected to motors A211 as an image forming drive unit and sensors A214 for monitoring the motors via an address bus or a data bus, respectively.

On the other hand, the paper conveyance control board 600 includes a mechanical load control section B608. The mechanical load control section B608 is connected to motors B611 as a sheet conveyance drive section and sensors B614 for monitoring the motors by an address bus or a data bus, respectively.

In such a control configuration, the image forming control board 200 controls the image forming components of the image forming apparatus 100. That is, the image forming control board 200 drives each load for forming an image in the image forming apparatus 100, collects and analyzes information from sensors, and controls the image forming apparatus 100 and the user interface (UI) 126. It plays the role of exchanging data, etc. The CPU 201a of the image forming control board 200 executes various sequences related to a predetermined image forming sequence according to a program stored in the ROM 201b.

The CPU 201a communicates with the mechanical load control section A208 in the image forming control board 200 and the mechanical load control section B608 in the paper conveyance control board 600. That is, the CPU 201a controls the motors A 211 related to image formation and the motors B 611 related to paper transport based on signals from sensors A 214 related to image formation and sensors B 614 related to paper transport to execute an image forming operation. The ROM 201b is a storage unit that stores various data related to image formation.

The RAM 201c stores rewritable data that needs to be stored temporarily or permanently. That is, the RAM 201c stores, for example, high voltage setting values of the high voltage control unit 501, various data, image forming command information from the user interface (UI) 126, and the like. A user interface (UI) 126 acquires information such as copy magnification and density settings set by the user. Further, the user interface (UI) 126 sends data for notifying the user of the status of the image forming apparatus 100, such as the number of images to be formed, information on whether or not images are being formed, the occurrence and location of a jam, etc. .

The image forming apparatus 100 includes DC loads such as motors, and sensors such as photointerrupters and microswitches arranged at various locations inside the apparatus. An operation for forming an image is performed by driving a motor and each DC load as appropriate, and various sensors monitor the operation.

The high voltage unit 500 is composed of a unit including electric wires and wire springs for applying high voltage. The high voltage control unit 501 receives a command from the CPU 201a, controls the application of high voltage, and applies an appropriate high voltage to the primary charger 109 and the like. A heater 401 built into the fixing unit 400 is ON/OFF controlled by the CPU 201a.

Next, the operation of the image forming apparatus 100 having such a configuration will be explained.

When the document reading device 120 of the image forming apparatus 100 reads a document and an image formation start signal is issued, the rotating photoconductor drums 104Y to 104K of each process cartridge 103Y to 103K are charged with the corresponding primary chargers 109 (Y to K) to a uniform negative polarity. Next, each exposure section of the laser scanner unit 108 irradiates laser light corresponding to the color-separated image signal to expose the corresponding photoreceptor drums 104Y to 104K, and each color is printed on the photoreceptor drums 104Y to 104K. A corresponding electrostatic latent image is formed.

Next, from the developing devices 105 (Y to K) to which a developing bias of the same polarity as the charged polarity (negative polarity) of the photoconductor drum is applied, the electrostatic latent images on the photoconductor drums 104Y to 104K are applied respectively. Colored toners are provided and each electrostatic latent image is visualized as a toner image. The toner images formed on the photoreceptor drums 104Y to 104K are sequentially transferred to the intermediate transfer belt 101 by primary transfer rollers 114 (Y to K) to which a primary transfer bias (opposite polarity (positive polarity) to the toner) is applied. Ru.

The yellow, magenta, cyan, and black toner images transferred to the intermediate transfer belt 101 are superimposed on the intermediate transfer belt 101 to form a full-color toner image. At this time, the transfer residual toner remaining on the photoreceptor drums 104Y to 104K without being transferred to the intermediate transfer belt 101 is scraped off by the cleaning blade of the corresponding drum cleaner 112 (Y to K) and collected.

The full-color toner image formed on the intermediate transfer belt 101 moves as the intermediate transfer belt 101 rotates to the secondary transfer portion Te where the drive roller 116 and the secondary transfer roller 117 come into contact. At this time, the paper P is carried into the secondary transfer section Te in synchronization with the timing at which the leading edge of the toner image moves to the secondary transfer section Te.

That is, the paper P accommodated in the paper feed cassette 121 or the manual feed tray 122 is carried out by the paper feed roller 135, conveyed by the pull-out roller 136, and conveyed via the registration roller 123 to the secondary transfer section Te. The toner images on the intermediate transfer belt 101 are transferred all at once to the paper P carried into the secondary transfer portion Te by the secondary transfer roller 117 to which a secondary transfer bias is applied (secondary transfer). At this time, the secondary transfer bias applied to the secondary transfer roller 117 has a positive polarity opposite to that of the toner. During the secondary transfer, toner remaining on the intermediate transfer belt 101 without being transferred to the paper P is scraped off by the transfer belt cleaner 107 and collected as recovered toner.

The paper P on which the toner image has been transferred is carried into the fixing unit 400 on the downstream side in the paper transport direction, and the toner image is heated and pressed onto the paper P at the fixing nip where the fixing roller 118 and the pressure roller 119 come into contact. Fixed by heat. The paper P on which the toner image has been fixed is ejected onto a paper ejection tray 125 by a paper ejection roller 124 .

Next, a description will be given of the positional relationship between each component in the image forming apparatus 100 and a control board that controls the component.

FIG. 3 is a rear view showing the positional relationship between each component in the image forming apparatus of FIG. 1 and a control board that controls the component.

In FIG. 3, arrow A indicates vertically upward. In FIG. 3, portions indicated by broken lines indicate each component disposed between the front and rear side plates of the main body of the image forming apparatus 100. Each component is supported and fixed by fixing members attached to the front and rear side plates of the device main body.

That is, fixing members made of sheet metal or the like are attached to the front and rear side plates of the main body of the apparatus, and these fixing members allow the photosensitive drums 104 (Y to K), the developing devices 105 (Y to K), and the laser scanner to be connected to each other. The unit 108, intermediate transfer belt 101, etc. are fixed at predetermined positions.

The positional relationship between the photoreceptor drum 104 (Y to K) and each exposure section of the laser scanner unit 108 is defined so that the surface of the photoreceptor drum 104 (Y to K) can be exposed with high precision by the exposure section. ing. In addition, the positional relationship between the photoreceptor drums 104 (Y to K) and the developing device 105 (Y to K) and the positional relationship between the photoreceptor drums 104 (Y to K) and the intermediate transfer belt 101 are also precisely controlled by the fixing member. stipulated in

A paper feed cassette 121 is disposed at the bottom of the apparatus main body, and the paper feed cassette 121 is arranged horizontally so that the paper stored therein is substantially parallel to the bottom plate of the apparatus main body. The paper feed cassette 121 is arranged vertically below the laser scanner unit 108. A process cartridge 103 (YK) including a photoreceptor drum 104 (YK) and a developing device 105 (YK) is arranged vertically above the laser scanner unit 108.

An intermediate transfer belt 101 is arranged above the process cartridges 103 (Y to K). Inside the endless intermediate transfer belt 101, primary transfer rollers 114 (Y to K) are positioned so as to face the photoreceptor drums 104 (Y to K), respectively. Furthermore, the positions of toner bottles 130Y to 130K are defined above the process cartridge 103 (Y to K) in the vertical direction. The position of the paper discharge tray 125 is defined above the toner bottles 130Y to 130K.

The motors A211 that drive the photosensitive drums 104 (Y to K), the developing devices 105 (Y to K), the intermediate transfer belt 101, the primary transfer rollers 114 (Y to K), etc. are main drives that are image forming support members. It is incorporated in unit 222. The main drive unit 222 also incorporates gears that transmit the driving force of the motors A211 to each component, and sensors A214 that monitor the motors A211.

The developing motor 211a drives the developing screw of the developing device 105 (YK). The color drum motor 211b drives the photosensitive drums 104Y, 104M, and 104C corresponding to colors other than black (Bk). The Bk drum ITB motor 211c drives the black (Bk) photosensitive drum 104K and the drive roller of the intermediate transfer belt 101.

The developing motor 211a, the color drum motor 211b, and the Bk drum ITB motor 211c are arranged near the components they drive, and the sensors A214 are also arranged near the motors they monitor. This allows the image forming components to be integrated and the device to be more compact.

The image forming control board 200 functions as an image forming control section that controls the driving of motors A211 such as the developing motor 211a, the color drum motor 211b, and the Bk drum ITB motor 211c. The image forming control board 200 is also attached to the main drive unit 222 so as to be integrated with the main drive unit 222. This allows the motors A211 and the control unit that controls them to be handled as one unit.

In FIG. 3, the power supply board 202 is disposed on the lower rear side of the apparatus main body, facing the paper feed cassette 121 below the main drive unit 222. The power supply board 202 distributes or converts AC power input from a commercial power source into DC power. Therefore, the power supply board 202 is placed at the bottom of the device body closest to the cable 220 that supplies commercial power.

On the other hand, a user interface (UI) 126 is arranged on the front of the upper left part of the apparatus main body. Further, a high voltage unit 500 is arranged above the intermediate transfer belt 101 and on the upper right side of the image forming control board 200 when viewed from the back side. Further, a fixing unit 400 is arranged at the upper left of the image forming control board 200 when viewed from the back, and a fixing motor 215 is arranged near the fixing unit 400. The fixing motor 215 rotationally drives at least one of the fixing roller 118 and the pressure roller 119 of the fixing unit 400.

According to this embodiment, the motors A211 that drive image forming components such as the photosensitive drums 104 (Y to K) and the developing devices 105 (Y to K) are collectively supported by the main drive unit 222. ing. As a result, the device can be made more compact, and they can be attached to or removed from the device body as one unit. The image forming control board 200 is also integrated into the main drive unit 222 . The image formation control board 200 controls drive members for image formation.

By integrating the motors and the control board that controls the motors, the image forming motors A211 and the image forming control board that controls them can be attached to or removed from the apparatus body as one unit. be able to.

Therefore, since the motors and the control section are integrated, for example, if one photoconductor drum does not operate normally, there is no need to determine whether the problem is with the motor or the control section, and the entire main drive unit 222 can be replaced with a new one. The problem can be resolved by replacing it. In addition, at this time, the replacement work is easier and faster than replacing the motor that drives the photoreceptor drum or the control board individually, so it is possible to reduce downtime of the image forming apparatus. .

Next, a description will be given of the positional relationship between the structural members related to sheet conveyance and the control board that controls the structural members.

A paper feed roller 135, a pull-out roller 136, a registration roller 123, etc. provided in a paper transport path 145 are defined at predetermined positions by fixing members provided on the front and rear side plates of the apparatus main body. The paper feeding rollers 135 start feeding the paper P in the paper cassette 121, the pulling rollers 136 transport the fed paper P, and the registration rollers 123 adjust the inclination of the transported paper P. Each positional relationship is specified to be corrected.

Motors B611 that drive the paper feed roller 135, pull-out roller 136, registration roller 123, etc. are collectively incorporated into a transport drive unit 666, which is a paper transport support member. The transport drive unit 666 also incorporates gears that transmit the driving force of the motors B611 to each component, and sensors B614 that monitor the motors B611.

The drive motor 611a drives a paper feed roller (135 in FIG. 1), and the drive motor 611b drives a pull-out roller (136 in FIG. 1) downstream of the paper feed roller. Further, the drive motor 611c drives a registration roller (numeral 123 in FIG. 1). The drive motors 611a, 611b, and 611c are arranged near the rollers to be driven, respectively, and the sensors B614 are also arranged near the motors to be monitored. As a result, the structural members for paper conveyance are integrated, and the apparatus is made more compact.

The paper conveyance control board 600 functions as a conveyance control section that controls driving of motors B611 such as drive motors 611a, 611b, and 611c. The paper conveyance control board 600 is also attached to the conveyance drive unit 666 so as to be integrated with the conveyance drive unit 666. This allows the motors B611 and the control unit that controls them to be handled as one unit.

According to this embodiment, the motors B611 that drive the paper feed roller 135, the pull-out roller 136, the registration roller 123, etc. are collectively supported by the transport drive unit 666. Thereby, the motors B611 can be attached to or detached from the apparatus main body as one unit. A paper conveyance control board 600 is also integrated into the conveyance drive unit 666. A paper conveyance control board 600 controls a drive member for conveying paper.

By integrating the motors and the control unit that controls the motors, the paper transport motors B611 and the paper transport control board that controls them can be attached or removed as one unit from the apparatus main body. be able to.

Therefore, according to the present embodiment, for example, if one conveyance roller does not operate normally, the problem can be solved by replacing the entire conveyance drive unit 666 with a new one without determining whether the problem is with the motor or the control unit. can be resolved. In addition, at this time, the replacement work is easier and faster than replacing the motors that drive the transport rollers or their control boards individually, and can be done in a short time, reducing downtime when the main body of the device cannot be operated. It can be shortened as much as possible.

In this embodiment, the paper transport path is preferably a vertical path transport path. As shown in FIG. 3, the vertical path conveyance path allows the motors that drive the conveyance rollers to be concentrated in a compact manner, for example, at one location on the lower left side of the image forming apparatus 100. Therefore, it becomes easier to support the motors B611 together on the transport drive unit 666, and it becomes easier to integrate the motors B611 and the control board that controls them.

In this embodiment, the CPU 201a, ROM 201b, and RAM 201c are built into the image forming control board 200, but the CPU 201a, ROM 201b, and RAM 201c can also be arranged outside the image forming control board 200. Further, in this embodiment, the quantities of various motors and sensors are not particularly limited, and the same effect can be obtained even if the quantities are changed.

In the present embodiment, the image forming apparatus 100 can be equipped with various devices applied to bookbinding, inserter, punching, stapling, etc. as a post-processing device, and in this case, similar effects can be obtained. can be played.

100 Image forming device 101 Intermediate transfer belt 103 Process cartridge 104 Photosensitive drum 105 Developing device 200 Image forming control board 211 Motors A
214 Sensors A
222 Main drive unit 600 Paper transport control board 611 Motors B
614 Sensors B
666 Transport drive unit

Claims (6)

an image forming means having a photoreceptor drum, forming an image on the photoreceptor drum, and transferring the image to a recording material;
a drum motor that drives the photoreceptor drum;
a first support member that supports the drum motor;
a first control board that controls driving of the drum motor;
a conveyance roller that conveys the recording material;
a conveyance motor that drives the conveyance roller;
a second support member that supports the transport motor;
a second control board that controls the transport motor;
has
The image forming apparatus is characterized in that the first control board is attached to the first support member, and the second control board is attached to the second support member. The conveyance roller conveys the recording material to a conveyance path,
2. The image forming apparatus according to claim 1, wherein the conveyance path is a vertical path conveyance path that conveys the recording material upwardly of the image forming apparatus. 3. The image forming apparatus according to claim 1, wherein the image forming means includes a developing device that develops the electrostatic latent image formed on the photosensitive drum. 4. The image forming apparatus according to claim 3, wherein the first control board further controls a developing motor that drives a developing screw provided in the developing device. 5. The image forming apparatus according to claim 1, wherein the first support member is provided with a gear that transmits the driving force of the drum motor to the photosensitive drum. 6. The image forming apparatus according to claim 1, wherein the second support member is provided with a gear that transmits the driving force of the transport motor to the transport roller.

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