JP2021022968A - Driving control device, driving device, sheet transfer device, and image formation device - Google Patents

Abstract

To achieve energy saving and a long life of a driving source when controlling a plurality of driving sources for driving the same driving object.SOLUTION: A driving control device 90 includes control means for controlling a plurality of driving sources 101, 102 that drive the same driving object 108. The control means selects and executes a first driving mode in which the same driving object is driven by the plurality of driving sources in a state of enabling the driving of the same driving object by the plurality of driving sources or a second driving mode in which the same driving object is driven by some of the plurality of driving sources.SELECTED DRAWING: Figure 5

Description

The present invention relates to a drive control device, a drive device, a sheet transfer device, and an image forming device.

Conventionally, a drive control device including a control means for controlling a plurality of drive sources for driving the same drive target has been known.

For example, in Patent Document 1, in a drive control device that controls two motors (drive sources) that drive a rotating body (same drive target), when one motor fails, the rotation is performed only by the other motor. It is disclosed to control the body to drive.

However, in the conventional drive control device that controls a plurality of drive sources that drive the same drive target, there is no control for the purpose of saving energy and extending the life of the drive source.

In order to solve the above-mentioned problems, the present invention is a drive control device including control means for controlling a plurality of drive sources for driving the same drive target, wherein the control means is based on the plurality of drive sources. A first drive mode in which the same drive target is driven by the plurality of drive sources while the same drive target can be driven, or a part of the same drive target among the plurality of drive sources. It is characterized in that a second drive mode driven by a drive source is selected and executed.

According to the present invention, when controlling a plurality of drive sources that drive the same drive target, it is possible to save energy and extend the life of the drive sources.

The schematic block diagram of the printer which concerns on embodiment. The schematic explanatory view of the image-forming part for yellow of four image-making parts in the printer. The explanatory view of the vicinity of the side frame in the state which opened the side frame from the printer in the state of FIG. Schematic diagram of the paper feed device in the printer. The explanatory view which shows the drive device which drives the feed roller of the paper feed device. The block diagram which shows an example of the conventional drive control device. The block diagram which shows an example of the drive control device of embodiment. The block diagram of the drive control device of an embodiment. The block diagram of the drive control device at the time of execution of the 2nd mode which drives only the 1st motor. The block diagram of the drive control device at the time of execution of the 3rd mode which drives only the 2nd motor. The flowchart which shows an example of the mode selection procedure in an embodiment. The flowchart which shows the flow of control during execution of the 2nd mode or 3rd mode which drives a feed roller by only one motor. Explanatory drawing which showed the display content of the touch panel which is a printer operation part when a user selects a paper type information. Explanatory drawing which showed the display content of the touch panel when a user selects a transport speed. An explanatory diagram showing the display contents of the touch panel displayed when notifying the user of a motor failure.

Hereinafter, an embodiment in which the drive control device of the present invention is applied to a color laser printer (hereinafter, simply referred to as “printer 500”) which is a tandem type image forming device in which a plurality of photoconductors are arranged in parallel will be described. This will be described with reference to FIGS. 1 to 3.
The present invention can also be applied to an image forming apparatus such as a copier, a facsimile, or a multifunction device having any two or three functions of a copier, a facsimile, and a printer other than a color laser printer. Further, the image forming method is not limited to the electrophotographic method, and can be applied to an image forming apparatus such as an inkjet method and a stencil printing method. It can also be applied to an image reading device that does not have an image forming device. Further, any device provided with a drive device for driving the drive target can be applied to any device other than an image forming device and an image reading device.

FIG. 1 is a schematic configuration diagram of a printer 500 according to the present embodiment.
The printer 500 includes an image forming unit 200, a paper feeding unit 300 arranged under the image forming unit 200, and the like. Inside the apparatus of the printer 500, four image forming units 1 (1Y) are used as image forming units for forming images of each color of yellow (Y), cyan (C), magenta (M), and black (Bk). , 1M, 1C, 1Bk). The image forming unit 1 (1Y, 1M, 1C, 1Bk) is provided with a drum-shaped photoconductor 2 (2Y, 2M, 2C, 2Bk), and the four photoconductors 2 (2Y, 2M, 2C, 2Bk) are In the image forming unit 200, they are arranged in parallel at equal intervals in the left-right direction in the drawing. Each photoconductor 2 (2Y, 2M, 2C, 2Bk) rotates in the direction of the arrow when the drive is transmitted from the drive source during the operation of the printer 500.

Around each photoconductor 2 (2Y, 2M, 2C, 2Bk), members and devices necessary for electrophotographic image formation, such as a developing device, are arranged, and four image forming units 1 (1Y, 1M, 1C) are provided. 1Bk) is configured. In the description of the present embodiment, for convenience, Y (yellow), C (cyan), and M (cyan) representing the colors are added after the numbers indicating the constituent members of each image-forming unit 1 so as to correspond to the toner color of the image to be imaged. (Magenta) and Bk (black) will be added as subscripts. In particular, in general description, these subscripts may be omitted.

In the printer 500, all four image forming units 1 (1Y, 1M, 1C, 1Bk) have almost the same configuration except that the colors of the toners used are different.

FIG. 2 is a schematic explanatory view of the image forming section 1Y for yellow among the four image forming sections 1 (1Y, 1M, 1C, 1Bk).
As shown in FIG. 2, in the image forming unit 1Y, image forming members such as a charging device 4Y, a developing device 5Y, and a cleaning device 3Y are sequentially arranged around the photoconductor 2Y according to an electrostatic photographic process. The charging device 4Y includes a charging roller 4aY facing the photoconductor 2Y, and the developing device 5Y includes a developing roller 5aY, a developing blade 5bY, a screw 5cY, and the like. Further, the cleaning device 3Y includes a cleaning brush 3aY, a cleaning blade 3bY, a recovery screw 3cY, and the like.

As the photoconductor 2Y, for example, one having a layer structure in which an organic semiconductor layer which is a photoconducting substance is provided on the surface of an aluminum cylinder having a diameter of about 30 to 120 [mm] can be used. It is also possible to use a belt-shaped photoconductor.

As shown in FIG. 1, below the photoconductor 2 (2Y, 2C, 2M, 2Bk), a laser beam 8 corresponding to image data of each color is applied to each photoconductor 2 uniformly charged by each charging device 4. An exposure device 80 is provided as a latent image forming means for scanning the surface to form an electrostatic latent image. An elongated space is secured between each charging device 4 and each developing device 5 in the direction of the rotation axis of the photoconductor 2 so that the laser beam 8 irradiated by the exposure device 80 enters toward the photoconductor 2. ing.

The exposure device 80 shown in FIG. 1 is a laser scan type exposure device using a laser light source, a polygon mirror, or the like, and is a laser beam 8 (8Y, 8C) modulated from four semiconductor lasers according to image data to be formed. , 8M, 8Bk). The exposure apparatus 80 houses optical parts and control parts in a metal or resin housing, and is provided with a translucent dustproof member at the outlet on the upper surface. Although the printer 500 shown in FIG. 1 is composed of one housing, a plurality of exposure devices may be individually provided in each image forming unit. Further, in addition to the exposure apparatus that employs laser light, an exposure apparatus that combines a known LED array and an imaging means can also be adopted.

When each color toner of yellow (Y), cyan (C), magenta (M), and black (Bk) is consumed by the developing device 5 (5Y, 5C, 5M, 5Bk) that handles each color, it is detected by the toner detecting means. Will be done. Then, the toner cartridges 40 (40Y, 40C, 40M, 40Bk) containing the toners of each color provided in the upper part of the printer 500 are supplied to each developing apparatus 5 by the toner replenishing means.

The outer shell of each toner cartridge 40 is a container made of resin, paper, or the like, and has a discharge port in a part thereof, and can be easily attached to and detached from the mounting portion 400 of the printer 500. When attached, this outlet is coupled to an individual toner replenishment means provided in the printer 500 body. Further, in the printer 500, the shapes of the mounting portion 400 and the toner cartridge 40 are erroneously set so that the toner cartridges 40 of each color are not erroneously mounted and the toner is not replenished to the developing device that handles different colors. Wearing prevention means are provided.

The developing apparatus 5 is provided with two screws 5cY for stirring and transporting the toner and the carrier, as typically shown by the image forming unit 1Y for yellow in FIG. When the developing device 5Y is mounted on the printer 500, one end of the toner replenishing means described above is connected to the upper part of the screw 5cY on the left side in FIG. The toner is supplied to the developing roller 5aY rotating in the direction of the arrow by the screw 5cY, and the thickness of the toner layer on the surface of the developing roller 5aY is regulated by the developing blade 5bY so as to have a predetermined thickness.

The developing roller 5aY is a cylinder made of stainless steel or aluminum, and is supported by a frame of the developing device 5Y so as to be rotatable and a regular distance from the photoconductor 2Y, and a predetermined magnetic field line is formed inside. It is equipped with a magnet. The electrostatic latent image for each color formed on the surface of each photoconductor 2 by the laser beam 8 is developed by a developing device 5 that handles toner of a predetermined color and becomes a manifest image.

An intermediate transfer unit 6 is provided above the photoconductor 2 (2Y, 2C, 2M, 2Bk). An intermediate transfer belt 6a as an image carrier hung on a plurality of rollers 6b, 6c, 6d, 6e is provided, and the intermediate transfer belt 6a rotates in the direction of the arrow as the roller 6b whose drive is transmitted by the drive source rotates. Run. The intermediate transfer belt 6a is endless and is hung so that the surfaces of the photoconductors 2 after passing through the portion facing the developing apparatus 5 come into contact with each other. Four primary transfer rollers 7 (7Y, 7C, 7M, 7Bk) are provided on the inner peripheral portion of the belt so as to face each photoconductor 2.

A belt cleaning device 6h is provided on the outer peripheral portion of the intermediate transfer belt 6a at a position facing the cleaning facing roller 6e. The belt cleaning device 6h wipes off unnecessary toner and foreign matter such as paper dust remaining on the surface of the intermediate transfer belt 6a. The cleaning facing roller 6e facing the belt cleaning device 6h includes a mechanism for applying tension to the intermediate transfer belt 6a. Although it always moves to secure an appropriate belt tension, the belt cleaning device 6h facing the intermediate transfer belt 6a of the cleaning facing roller 6e can also move in conjunction with the movement.

As the intermediate transfer belt 6a, for example, a belt having a resin film or rubber as a substrate having a thickness of 50 to 600 [μm] is suitable. The belt has a resistance value that enables the toner image carried by each photoconductor 2 to be electrostatically transferred to the belt surface by a bias applied to each primary transfer roller 7. Each member related to the intermediate transfer belt 6a included in the printer 500 is integrally supported with the intermediate transfer belt 6a and is configured as an intermediate transfer unit 6, and can be attached to and detached from the printer 500.

As an example of the intermediate transfer belt, the intermediate transfer belt 6a is obtained by dispersing carbon in polyamide and adjusting the volume resistance value to about 10 ⁶ to 10 ¹² [Ωcm]. Further, the intermediate transfer belt 6a is provided with belt retaining ribs on one side or both side ends of the belt to stabilize the running of the belt.

As an example of the primary transfer roller, the primary transfer roller 7 of the printer 500 has a surface of a metal roller serving as a core metal coated with a conductive rubber material, and a bias is applied to the core metal portion from a power source. Conductive rubber material carbon is dispersed in urethane rubber, the resistance to volume resistivity 10 5 ^[Ωcm] degree is adjusted. As the primary transfer roller, a metal roller having no rubber layer can also be adopted. A secondary transfer roller 14a is provided on the outer periphery of the intermediate transfer belt 6a at a position facing the secondary transfer opposing roller 6b as a support roller with the intermediate transfer belt 6a sandwiched between them. The secondary transfer roller 14a is a metal roller whose core metal is a metal roller coated with conductive rubber, and a bias is applied to the core metal portion from the power supply 14b. Wherein the conductive rubber and the carbon is dispersed, the volume resistivity are those resistant to 10 7 ^[Ωcm] degree is adjusted.

The secondary transfer roller 14a abuts on the intermediate transfer belt 6a at a position facing the secondary transfer facing roller 6b to form a secondary transfer nip as a secondary transfer portion. In the secondary transfer nip, the toner image carried by the intermediate transfer belt 6a is generated by applying a bias while passing the transfer paper S (paper) which is a recording medium between the intermediate transfer belt 6a and the secondary transfer roller 14a. It is electrostatically transferred to the transfer paper S.

A plurality of stages, for example, two stages of paper feed cassettes 9A and 9B are arranged in a paper feed unit 300 below the exposure apparatus 80 so that they can be pulled out. The transfer paper S stored in these paper feed cassettes is selectively sent out by the rotation of the corresponding calling rollers 10A and 10B, and is sent to the paper feed path P1 by the separation rollers 11A and 11B and the transfer rollers 12A and 12B. Sent.

The paper feed path P1 is provided with a timing roller pair 13 composed of a pair of rollers in order to take a feeding timing for feeding the transfer paper S to the secondary transfer unit. The transfer paper S is conveyed from the timing roller pair 13 toward the secondary transfer nip composed of the intermediate transfer belt 6a and the secondary transfer roller 14a.

The printer 500 is provided with a manual feed tray 25 as a manual paper feed unit on the right side in FIG. 1, and the manual feed tray 25 is rotated when not in use to form a side frame F which is a part of the printer 500 main body. Can be stored in. The uppermost transfer paper S stored in the manual feed tray 25 is fed by the manual feed calling roller 26. Then, it is separated by the reverse roller 27 as a separation means so that only one sheet is reliably conveyed, and is sent to the timing roller pair 13 via the paper feed path P1 by the transfer roller pairs 22 and 24.

A fixing device 15 having a heating means is provided above the secondary transfer nip. The fixing device 15 included in the printer 500 includes a fixing roller 15a having a built-in heater and a pressure roller 15b that comes into contact with the fixing roller 15a while applying pressure. The fixing device is not limited to such a configuration, and a belt-based type and a heating method that employs IH can be appropriately adopted.

The switching guide 63 is rotatable and is in the state shown in the drawing, so that the transfer paper S that has been fixed is guided to the guide member 61a that forms the paper ejection path. The transfer paper S guided by the guide member 61a is discharged as shown by an arrow D in FIG. 1 by the rotation of the paper ejection roller 62, and is stacked on the output tray 60 above the printer 500.

The printer 500 of FIG. 1 has a double-sided unit provided with a re-feeding path and rollers for reversing and re-feeding the transfer paper S so that an image can be automatically formed on both sides of the transfer paper S. doing. Specifically, the switching guide 63, which is provided with the switchback path P5 and the re-feeding path P6 inside the side frame F, and conveys the transfer paper S having finished image formation to the feeding path P1 on one side. A second switching guide G2 and a third switching guide G3 are provided.

Further, it is provided with a reversing roller 18a, a reversing roller 22 and the like which are connected to a drive source and can be reversed (forward / reverse rotation) by controlling the drive source. The rollers 23 and 24 are in contact with the reversing roller 22. When the reversing roller 22 rotates clockwise, the paper is conveyed from the bypass tray 25 in cooperation with the roller 24. Further, when rotating in the counterclockwise direction, the transfer paper S in the re-feeding path P6 is re-fed in the direction of the timing roller pair 13 in cooperation with the roller 23.

When the switching guide 63 rotates clockwise from the state shown in the drawing, the transfer paper S that has been fixed is guided to the reversing transfer path P4 by the roller pair 17, and is conveyed to the reversing roller pair 18 via the second switching guide G2. And once sent to the switchback path P5. After the transfer paper S is sent to the switchback path P5, the reversing roller 18a of the reversing roller pair 18 rotates counterclockwise, and the second switching guide G2 rotates counterclockwise, whereby the transfer paper S Is sent from the switchback path P5 to the refeed path P6. In the refeed path P6, the transfer paper S conveyed by the roller pairs 15c and 20 and the roller pairs 14c and 21 is further conveyed to the roller pairs 22 and 23 and reaches the timing roller pair 13.

The printer 500 shown in FIG. 1 is provided with a paper feed device 50, which is an additional paper feed unit, below the paper feed unit 300. The paper feed device 50 shown in FIG. 1 is provided with two paper feed cassettes 9C and 9D, but a larger number of types can also be adopted, and a type with a built-in paper feed cassette with a larger number of paper storages can also be adopted. Good.

In the printer 500, the third switching guide G3 located above the fixing device 15 and downstream in the transport direction of the roller pair 17 rotates counterclockwise from the state shown in FIG. 1 to guide the transfer paper S after fixing. It can be conveyed to the paper ejection path P3 and discharged to another paper ejection device. As another paper ejection device, for example, a bin tray having several stages of paper ejection trays.

Next, the operation at the time of single-sided printing in which an image is formed on one side of the transfer paper S by the printer 500 will be described.
First, an electrostatic latent image is obtained by irradiating the surface of the photoconductor 2Y uniformly charged by the charging roller 4aY with the laser beam 8Y corresponding to the image data for yellow emitted from the semiconductor laser by the operation of the exposure apparatus 80. Is formed. This electrostatic latent image is developed by the developing roller 5aY and developed with yellow toner to become a visible image, which is transferred to the surface of the intermediate transfer belt 6a that moves in synchronization with the photoconductor 2Y by the primary transfer roller 7Y. Is primary transferred. Such latent image formation, development, and primary transfer operations are sequentially performed in the same manner on the other photoconductors 2 (2C, 2M, 2Bk) at the same timing.

As a result, the yellow Y, cyan C, magenta M, and black Bk color toner images are supported on the surface of the intermediate transfer belt 6a as four-color toner images that are sequentially overlapped, and the intermediate surface moves in the direction of the arrow. It is conveyed together with the transfer belt 6a. On the other hand, the cleaning device 3 cleans the surface of the photoconductor 2 that has passed through the position facing the primary transfer roller 7 with the intermediate transfer belt 6a sandwiched between them for residual toner and foreign matter.

The four-color toner image formed on the intermediate transfer belt 6a is transferred onto the transfer paper S which is conveyed in synchronization with the intermediate transfer belt 6a under the transfer action of the secondary transfer roller 14a. Then, on the intermediate transfer belt 6a side, the surface thereof is cleaned by the belt cleaning device 6h to prepare for the next image formation / transfer step. The transfer paper S on which the image is transferred is subjected to a fixing action by the fixing device 15, and is discharged to the paper ejection tray 60 by the paper ejection roller 62 with the image surface facing downward (face down).

Next, an operation during double-sided printing in which an image is formed on both sides of the transfer paper S by the printer 500 will be described.
The image is transferred from the intermediate transfer belt 6a to one side by the same operation as in the single-sided printing described above, and the transfer paper S that has passed through the fixing device 15 is guided toward the roller pair 17 by the switching guide 63. The transfer paper S advancing upward of the second switching guide G2 at the rotation position in FIG. 1 via the third switching guide G3 and the reversing transport path P4 provided on the downstream side in the transport direction of the roller pair 17 is the reversing roller pair. It is conveyed to the switchback path P5 by 18.

At this time, the reversing roller 18a is rotationally driven in the clockwise direction. The roller pair 19 in the switchback path P5 is also a roller pair capable of forward and reverse rotation, and once the transfer paper S is received in the switchback path P5, it is reversed and the transfer paper S is fed back. When the rotation directions of the roller pair 19 and the reversing roller pair 18 are reversed, the second switching guide G2 rotates counterclockwise from the posture shown in FIG.

Then, the rear end of the transfer paper S until it enters the switchback path P5 is used as the front end, and the roller pairs 15c and 20 and the roller pairs 14c and 21 convey the paper in the refeeding path P6 toward the feeding path P1. To reach the timing roller pair 13. After that, the transfer paper S having an image on one side is transported again toward the secondary transfer nip where the secondary transfer roller 14a and the intermediate transfer belt 6a face each other by timing with the timing roller pair 13. The toner image on the intermediate transfer belt 6a is transferred to the other side of the transfer paper S.

The images to be formed on the second surface of the transfer paper S are sequentially formed by the image-drawing process that is started when the transfer paper S is conveyed to a predetermined place. The image forming step in this case is also the same as the full-color toner image formation at the time of single-sided printing described above, and the full-color toner image is supported on the intermediate transfer belt 6a. However, since the transfer paper S is inverted in the front-rear direction on the transport path, the image data emitted from the exposure apparatus 80 is created so that the image is imaged from the opposite direction in the paper transport direction when the image is first imaged. Is controlled and executed.

The transfer paper S on which the full-color toner image is transferred on both sides in this way is again subjected to the fixing process by the fixing device 15 and then discharged onto the paper ejection tray 60 by the paper ejection roller 62. In the printer 500, in order to improve the efficiency of double-sided image drawing, several sheets of transfer paper S can be simultaneously conveyed to the transfer path. Further, the formation timing of the image to be formed on the front and back of the transfer paper S is executed by the control means.

Further, in the printer 500, the polarity of the toner image formed on the photoconductor 2 is negative, and by giving a positive charge to the primary transfer roller 7, the toner image on the photoconductor 2 is transferred to the surface of the intermediate transfer belt 6a. Will be done. Further, by applying a positive charge to the secondary transfer roller 14a, the toner image on the surface of the intermediate transfer belt 6a is transferred to the transfer paper S.

Although these single-sided printing and double-sided printing operations have been described with an example of executing full-color printing, there are some photoconductors that are not used during monochrome printing using black. Not only does the unused photoconductor 2 (2Y, 2M, 2C) and the developing device 5 (5Y, 5M, 5C) not operate, but also these unused photoconductors 2 (2Y, 2M, 2C) and the intermediate transfer belt 6a It is equipped with a mechanism to keep it in non-contact. In the printer 500, the inner frame 6f that supports the rollers 6d and the primary transfer rollers 7Y, 7C, and 7M is rotatably supported around the frame shaft 6g.

During monochrome printing, the internal frame 6f is rotated in a direction away from the photoconductor 2 (2Y, 2M, 2C) (clockwise in FIG. 1) so that only the photoconductor 2Bk comes into contact with the intermediate transfer belt 6a. By performing the image process, a monochrome image with black toner is created. In this way, the photoconductor 2 (2Y, 2M, 2C) of the image forming unit 1 (1Y, 1M, 1C), which is not used during monochrome printing, is separated from the intermediate transfer belt 6a, and the photoconductor 2 (2Y, 2M, 2C). And stopping the developing device 5 (5Y, 5M, 5C) is advantageous in terms of improving the life of the image forming unit 1 (1Y, 1M, 1C).

In the printer 500, when maintenance or parts replacement is required, the exterior cover or the like is opened and maintenance is performed. At the time of this maintenance, operability is improved by replacing each member constituting the image forming unit 1 shown in FIG. 1 as a unitized process cartridge by integrally supporting the members.

Further, when the image forming unit 1 shown in FIG. 1 is configured as a process cartridge, a guide unit and a handle for mounting on the printer 500 are provided to facilitate attachment / detachment. In addition, if a storage device (for example, an IC tag) that stores the characteristics and operating status of the process cartridge is provided, it serves as a guideline for maintenance and enhances the convenience of maintenance management of the process cartridge.

Further, when the intermediate transfer unit 6 is to be maintained or replaced, the intermediate transfer belt 6a and each photoconductor 2 may be separated from each other so that the intermediate transfer unit 6 is pulled out from the printer 500 main body.

FIG. 3 is an explanatory view of the vicinity of the side frame F in a state where the side frame F is opened from the printer 500 in the state of FIG. The side frame F includes a double-sided unit 30 and a secondary transfer unit 14, and is rotatable with respect to the printer 500 with the lower rotation shaft Fa as the center of rotation, and is lateral from the state shown in FIG. As shown in FIG. 3, the structure is such that the upper part can be opened when the frame F is rotated.

Further, an engaging projection 71 as an engaged member is provided on the upper surface of the side frame F. The engaging projection 71 is an engaging portion of a pull-in device 70 provided on the upper part of the printer 500 when the secondary transfer unit 14 and the double-sided unit 30 are moved in the closing direction in order to mount the secondary transfer unit 14 and the double-sided unit 30 on the printer 500. Engage with. When the engaging projection 71, which is the engaged member of the side frame F, engages with the engaging portion of the pulling device 70, the pulling device 70 pulls the side frame F toward the printer 500.

When the frame is pulled in by the pulling device 70, the guide portion 31a of the stopper member 31 comes into contact with the blocking member 32. Then, the stopper member 31 is rotated by the pulling force of the pulling device 70 to get over the blocking member 32, the side frame F is closed, and the secondary transfer unit 14 and the double-sided unit 30 are mounted at the mounting positions.

Prior to opening the side frame F, the stopper member 31 provided on the side frame F is rotated by operating the lock lever to remove the stopper member 31 from the blocking member 32 provided on the printer 500 side. Release the function and open it. As shown in FIG. 3, since a plurality of transport paths (P1, P2, P6) can be opened by opening the side frame F, it is easy to treat the jam transfer paper S generated in these transport paths. it can.

The secondary transfer unit 14 in which the transfer path P2 and the refeed path P6 are formed on both sides of the transfer path P2 has the center of the roller 23 as the center of rotation, and when the side frame F is opened as shown in FIG. The next transfer roller 14a separates from the intermediate transfer belt 6a. Further, the secondary transfer unit 14 is provided with a rotational habit so that the roller 14c is separated from the roller 21. The secondary transfer unit 14 is a unit having a power supply 14b inside and a transfer paper S transfer function outside the case.

The fixing device 15 also has a transport roller 15c and a transport guide surface, and a part of the fixing device 15 constitutes a re-feeding path P6. The fixing device 15 is supported so as to be pulled out to the right side of the drawing in the state of FIG. Therefore, the paper jam generated inside the fixing device 15 can be easily processed.

The transport roller 15c is urged to the roller 20 side by a spring, and the transport roller 14c is urged to the roller 21 side by a spring. Further, the rollers on the printer 500 side of the transfer rollers 12A and 12B are urged by springs on the rollers 12Aa and 12Ba on the side frame F side of the transfer rollers 12A and 12B.

As a result, when the side frame F is in the closed position shown in FIG. 1, the side frame F is opened by the transfer roller 15c, the transfer roller 14c, and the transfer roller pairs 12A and 12B on the printer 500 side. Be urged. As a result, the stopper surface 31b of the stopper member 31 and the blocking member 32 come into contact with each other, and the side frame F is positioned.

Next, a paper feeding device as a sheet transporting device used in the printer 500 of the present embodiment will be described in more detail.
FIG. 4 is a schematic configuration diagram of the paper feeding device 50 according to the present embodiment.
Generally, the FRR paper feeding method and the RF paper feeding method are known as the paper feeding methods of the paper feeding device. In the FRR method (Feed and Reverse Roller method), a reverse torque is applied to a separate roller as a separating member in order to feed the sheets one by one. The RF method (Roller Friction method) does not apply reverse torque to the separate roller. The paper feed device 50 of this embodiment adopts the FRR method.

In FIG. 4, reference numeral 51 is a paper feed tray, reference numeral 52 is a paper guide, reference numeral 53 is a bottom plate, reference numeral 54 is a calling roller, reference numeral 55 is a feed roller, reference numeral 56 is a separate roller, reference numeral 58 is a grip roller, and reference numeral K1 is a front end. The detection means, reference numeral K2 is a paper detection means, reference numeral P is a bundle of papers, reference numeral P1 is a preceding paper, and reference numeral P2 is a next paper.

The FRR method has a feed roller 55 and a separate roller 56 that presses against the feed roller 55, and the feed roller 55 rotates in the feeding direction of the transfer paper S (paper), but the separate roller 56 feeds via a torque limiter. A driving force (reverse torque) is applied in the direction opposite to the direction. Since the FRR method applies reverse torque, the separation performance is higher than that of the RF method. Both methods have an advantage that the paper separation performance is not affected even if the positional relationship between the front edge position of the paper and the pressure contact portion (feed nip) between the feed roller 55 and the separate roller 56 is rough. Therefore, no extra cost is required to improve the position accuracy, and the paper feed method is suitable for the front loading type paper feed tray, which has become the mainstream in recent years.

In FRR-type and RF-type paper feed devices, paper is usually called from a bundle of paper by rotation of a calling roller 54 gear-connected to a feed roller 55. The calling roller 54 comes into contact with the uppermost paper of the paper bundle P, and feeds the paper (preceding paper S1) downstream in the transport direction. Then, the unwound leading paper S1 is fed to the downstream side in the transport direction by the feed roller 55 located on the downstream side of the paper feed tray 51. Even before the rear end of the leading paper S1 passes through the contact point of the calling roller 54, when the front end of the leading paper S1 reaches the grip roller 58 provided further downstream, the calling roller 54 is separated from the paper surface of the leading paper (or not). I'm trying to drive it. Then, when the front end of the preceding paper S1 is detected by the paper detecting means K2 located further downstream of the grip roller 58, the calling roller 54 is called to the maximum of the paper feed tray 51 in order to feed out the next paper S2 using this paper detection as a trigger. It is designed to come into contact with (or redrive) the paper surface of the upper paper (next paper S2).

On the other hand, the feed roller 55 is driven and stopped before the rear end of the preceding paper S1 crosses the feed nip in order to prevent paper jam. A one-way clutch is connected to the rotation shaft of the feed roller 55, and even if the drive of the feed roller 55 is stopped, the feed roller 55 itself rotates in the transport direction of the paper transported by the grip roller 58 (driven rotation). ). By stopping the drive of the feed roller 55 and rotating the separate roller 56 in the reverse direction, even if the front end of the next paper S2 reaches the feed nip following the rear end of the leading paper S1, the paper is surely separated. Paper jam does not occur due to uncontrollability between the preceding paper S1 and the next paper S2.

The start timing of the next paper S2 is triggered by the detection of the front edge of the preceding paper S1 by the paper detecting means K2 provided downstream of the grip roller 58 where the behavior of the paper is stable (the slip ratio is lowered). The trigger is set to start driving the calling roller 54 and the feed roller 55 at a predetermined timing that does not collide with the rear end of the preceding paper S1 and satisfies a predetermined print productivity.

By the way, in recent years, copiers and printers need to keep the paper speed at the time of image formation low for the purpose of high image quality and low power consumption, while high print speed (high print productivity) is also required. There is. For this reason, the paper speed is kept low, but the space between the papers in the paper feed section is set narrow to achieve both high image quality and high print productivity.

As described above, the FRR method and the RF method are cost-effective and suitable for the front loading type. However, in the conventional FRR method and RF method, as described above, the leading paper S1 and the next paper S2 of the paper feed tray 51 are fed out by using the front edge detection of the leading paper S1 by the front edge detecting means as a trigger. The space between the papers between S2 was relatively wide.

On the other hand, the distance from the front end position of the paper loading portion of the paper feed tray 51 to the feed nip of the feed roller 55 is the front wall 1a of the paper feed tray 51, the paper guide 52, and the paper cassette bottom plate 53 when a small amount of paper is loaded. It varies between 15 and 30 [mm] due to the retracting of the front edge of the paper bundle due to the rise. For this reason, a large variation occurs in the start position depending on whether or not the preceding paper S1 and the next paper S2 are taken out due to friction. That is, when there is take-out due to friction, the next paper S2 taken out due to friction with the preceding paper S1 may have already reached the feed roller 55 at the start of the next paper S2.

The start timing of the next paper S2 must be determined at a late timing so that the paper taken out to the position of the earliest feed roller 55 does not collide with the rear end of the preceding paper S1. Then, the actual space between the next paper S2 and the preceding paper S1 starting from the rearmost paper feed tray 51 becomes about 30 [mm] larger than the target paper, and the printing speed becomes large. It was a factor that hindered the speeding up of.

Therefore, in view of such a problem, in the present embodiment, as shown in FIG. 4, the front edge detecting means K1 of the paper is provided on the downstream side of the feed roller 55, and the speed of the next paper S2 is increased up to the front edge detecting means K1. I am trying to transport at the same transport speed.

In the paper feed device 50 of the present embodiment, after the rear end of the leading paper S1 exceeds the front edge detecting means K1, the front edge detecting means K1 detects the front edge of the next paper S2, and the leading paper S1 and the next paper S2 It is determined whether or not the minimum paper spacing δ that can be detected by the paper detecting means K2 is secured between them. That is, the paper spacing δ is calculated from the time when the front edge of the preceding paper S1 is detected by the paper detecting means K2, the length of the paper, and the time when the front edge of the next paper S2 is detected by the front edge detecting means K1. Then, the feeding state of the feed roller 55 is controlled so that the minimum paper spacing δ is formed when the front end of the next paper S2 reaches the paper detecting means K2 downstream of the grip roller 58. Further, when the front end of the next paper S2 is detected by the front end detecting means K1, if the front end of the preceding paper S1 has not reached the paper detecting means K2, the conveying of the next paper S2 is temporarily stopped and the start position of the next paper S2 is determined. I was doing it.

However, once the feeding of the next sheet S2 is stopped, a time loss occurs due to this stop. In order to make up for this time loss, a considerable increase in speed is required for the subsequent restart of feeding, and in order to support this increase in speed, a fairly large stepping motor is required for both the feed roller 55 and the grip roller 58, which causes a cost increase. Was there.

In the present embodiment, two motors for driving the feed roller 55 are provided, and by adopting a configuration in which the two motors drive the feed roller 55, which is the same drive target, the size and cost increase are suppressed.

FIG. 5 is an explanatory view showing a drive device 100 that drives the feed roller 55, which is a sheet transport member.
In this embodiment, an example in which the same drive target is driven by two motors will be described, but the same drive target may be driven by three or more motors. Further, a plurality of motors having the same drive target may have different motor capacities, types, and the like.

As shown in FIG. 5, the drive device 100 includes two motors, a first motor 101 and a second motor 102, as drive sources. The first gear 105 press-fitted into the motor shaft 101a of the first motor 101 meshes with the output gear 107, and the second gear has the same shape as the first gear 105 press-fitted into the motor shaft 102a of the second motor 102. 106 meshes with the output gear 107. The first gear 105 and the second gear 106 are meshed with the output gear 107 having a large number of teeth provided on the shaft 108 of the feed roller 55, which is the same drive target.

The driving force of the first motor 101 is transmitted to the shaft 108 of the feed roller 55 by decelerating the rotational motion by the first gear 105 and the output gear 107. The driving force of the second motor 102 is transmitted to the shaft 108 of the feed roller 55 by decelerating the rotational motion by the second gear 106 and the output gear 107. As a result, the feed roller 55 rotates by the driving force of the first motor 101 and the second motor 102. In this way, by driving the feed roller 55 using the two motors, a large driving torque can be generated, and it is possible to cope with the speed increase. In addition, it is possible to support speed increase at a lower cost than when a single high-output motor supports speed increase.

Further, an encoder 103 for detecting the axis angle of the motor shaft 101a is mounted coaxially with the motor shaft 101a of the first motor 101. The shaft angle information detected by the encoder 103 is transmitted to the drive control device 90 that drives and controls the first motor 101 and the second motor 102. The drive control device 90 performs drive control of the two motors 101 and 102 without interfering with the torques of the two motors by performing feedback control using the output information of the encoder 103. The means for detecting the shaft angle is not limited to the encoder, and any means such as a potentiometer that can detect the shaft angle of the motor may be used.

FIG. 6 is a block diagram showing an example of the conventional drive control device 90X.
The conventional drive control device 90X has a first control unit 91aX that controls the drive of the first motor 101, and a second control unit 91bX that controls the drive of the second motor 102. Each control unit performs PID control, which is a kind of feedback control.

The first control unit 91aX feeds back the position signal x1det and the angular velocity v1det from the encoder 103 that detects the axis angle of the motor shaft 101a of the first motor 101, and obtains the deviation between the position target value xtgt and the angular velocity vtgt. Then, based on the deviation, a current value or a voltage value as a drive control signal for driving the first motor 101 is output. The second control unit 91bX feeds back the position signal x2det and the angular velocity v2det from the encoder 104 that detects the axis angle of the motor shaft 102a of the second motor 102, and obtains the deviation between the position target value xtgt and the angular velocity vtgt. Then, based on the deviation, a current value or a voltage value as a drive control signal for driving the second motor 102 is output.

However, in the conventional drive control device 90X shown in FIG. 6, by providing a control unit that performs PID control for each motor, precise operations that differ for each motor (for example, when stopped, the first motor 101 and the second motor 102 are operated. It is possible to perform backlash correction by slightly offsetting the motor). However, on the other hand, it is necessary to provide a means for detecting an axial angle such as an encoder for performing PID control for each motor, a control circuit and a control board for performing PID control, and cost increase and equipment due to an increase in the number of parts. May lead to an increase in size. In addition, there is a drawback that the hardware configuration and control method become complicated.

Therefore, in the present embodiment, one PID control unit is used to drive and control a plurality of motors with the same drive control signal (voltage value or current value). As a result, drive control can be performed based on signals from a common encoder in a plurality of drive sources, and a control circuit and a control board for performing PID control can be integrated into one, so that the device can be miniaturized and the device can be used. It is possible to reduce the cost of. Therefore, it can be suitably used for an apparatus in which cost and miniaturization of the apparatus are prioritized over the functional aspect.

Here, in controlling the two motors 101 and 102 that drive the feed rollers 55 that are the same drive target, conventionally, only one of these motors 101 and 102 is used for reasons other than motor failure. There is no one that implements the control of driving the feed roller 55.

However, the drive load applied to the feed roller 55 or the drive torque required to drive the feed roller 55 is required depending on the type of paper (thickness, surface roughness, etc.) to be conveyed by the feed roller 55. It depends on the difference in paper transport speed. For example, when transporting thin types of paper or when transporting paper at a low transport speed, the drive torque required to drive the feed roller 55 is small, and the drive force of only one motor is sufficient. In some cases, the feed roller 55 can be driven. In such a case, if it is driven by only one motor, energy saving can be realized as much as the other motor is not driven, and the life of the other motor can be extended.

Therefore, in the present embodiment, even in a state where the feed rollers 55, which are the same drive targets, can be driven by the two motors 101 and 102 (a state in which neither motor has failed), these motors Only one of the 101 and 102 motors can be driven.

FIG. 7 is a block diagram showing an example of the drive control device 90'of the present embodiment.
The drive control device 90'of the example shown in FIG. 7 excludes the encoder 104 that detects the axial angle of the motor shaft 102a of the second motor 102 with respect to the conventional drive control device 90X shown in FIG. The position signal x2det and the angular velocity v2det of 102 are not fed back to the second control unit 91bX. As a result, the feedback signals are only the position signal x1det and the angular velocity v1det from the encoder 103 that detects the shaft angle of the motor shaft 101a of the first motor 101. By feedback control with a single feedback signal in this way, the feed roller 55, which is the same drive target, is driven by both the two motors 101 and 102 while preventing torque interference between the two motors 101 and 102. can do.

As the feedback signal, only the position signal x1det of the first motor 101 may be used, and the angular velocities v1det and v2det of the respective motors 101 and 102 may be used as the speed signal. In this case, the vibration damping performance of the device can be improved, and the control characteristics of the motors 101 and 102 can be adjusted according to the characteristics of the motors 101 and 102 and the required characteristics of the device.

Here, the conventional drive control device 90X shown in FIG. 6 and the drive control device 90'of the example shown in FIG. 7 are provided with a control unit that performs PID control for each motor, so that the precise operation differs for each motor. For example, when the first motor 101 and the second motor 102 are slightly offset when stopped, backlash correction can be performed). However, on the other hand, it is necessary to provide a means for detecting an axial angle such as an encoder for performing PID control for each motor, a control circuit and a control board for performing PID control, and cost increase and equipment due to an increase in the number of parts. May lead to an increase in size. In addition, there is a drawback that the hardware configuration and control method become complicated.

Therefore, in the present embodiment, one PID control unit drives and controls two motors 101 and 102 with the same drive control signal (voltage value and current value). As a result, drive control can be performed based on a signal from the encoder 103 common to the two motors 101 and 102, and a control circuit and a control board for performing PID control can be integrated into one, so that the device can be made compact. It is possible to reduce the cost of the equipment and the equipment. Therefore, it can be suitably used for an apparatus in which cost and miniaturization of the apparatus are prioritized over the functional aspect.

FIG. 8 is a block diagram of the drive control device 90 of the present embodiment.
As shown in FIG. 8, the drive control device 90 of the present embodiment has a control unit 91 common to the motors 101 and 102 that perform PID control, and a first mode for driving both the first motor 101 and the second motor 102. (First drive mode), second mode (second drive mode) that drives only the first motor 101, and third mode (second drive mode) that drives only the second motor 102. It has 92 and.

The mode switching unit 92 controls the first three-state buffer 94a as a signal blocking means arranged in the transmission path of the drive control signal between the control unit 91 and the first predriver 95a for driving the first motor 101. In the second three-state buffer 94b as a signal blocking means arranged in the transmission path of the drive control signal between the unit 91 and the second predriver 95b for driving the second motor 102, and the three-state buffers 94a and 94b, respectively. It is provided with a state command unit 93 that transmits a state command signal.

The state command unit 93 outputs a state command signal: High / Low to the three-state buffers 94a and 94b. The three-state buffers 94a and 94b block the drive control signal transmitted from the control unit 91 when the state command signal: Low is input, and control when the state command signal: High is input. The drive control signal transmitted from the unit 91 is transmitted to the pre-driver.

The example shown in FIG. 8 shows the state in the first mode for driving both the first motor 101 and the second motor 102, and the state command signal: High is input to the three-state buffers 94a and 94b. Has been done.

The control unit 91 feeds back the position signal xdet and the angular velocity vdet from the encoder 103 for detecting the shaft angle of the motor shaft 101a, and obtains the deviation between the position target value xtgt and the angular velocity vtgt. Then, based on the deviation, a drive command signal (PWM signal) and a direction command signal (DIR signal) as a common drive control signal for each motor are generated and transmitted to the motors 101 and 102. In the present embodiment, the PWM signal is used as the drive command signal, but the drive command signal may be a current value, a voltage value, or a combination thereof.

In the first mode set at the time of feeding, which is the normal operation, the state command signal: High is input to the three-state buffers 94a and 94b. Therefore, the drive command signal (PWM) as the drive control signal transmitted from the control unit to the motors 101 and 102 is transmitted to the pre-drivers 95a and 95b. As a result, the first motor 101 and the second motor 102 are driven, and the feed roller 55 is driven by both the first motor 101 and the second motor 102.

As described above, in the first mode, since both the first motor 101 and the second motor 102 are driven, a large driving force and a large driving torque can be obtained. Further, by providing a single negative feedback using a single control unit 91, a large driving force can be obtained with a simple and inexpensive configuration.

However, in the present embodiment, only a single drive control signal and a single negative feedback are viewed. Therefore, in the first mode, even if one of the two motors 101 and 102 fails, that Failure may not be detected properly.

Specifically, when one of the two motors 101 and 102 fails while driving under a high drive load state, the position signal xdet from the encoder 103 is significantly delayed due to the torque decrease. It occurs, or the drive command signal (current value, etc.) generated by the control unit 91 increases significantly. Therefore, the failure can be detected based on the position signal xdet and the drive command signal from the encoder 103. However, it is not possible to identify which motor is the failed motor.

Further, when one of the two motors 101 and 102 fails while driving under a low drive load state, the position signal xdet from the encoder 103 is not significantly delayed, so that the motor failure itself. Cannot be detected.

As described above, in the first mode, the failed motor may not be identified, or the motor failure itself may not be detected. Therefore, in the present embodiment, the inspection mode is provided, the second mode and the third mode are executed, and the failure detection of the motor is performed.

FIG. 9 is a block diagram of the drive control device 90 at the time of executing the second mode that drives only the first motor 101.
The second mode shown in FIG. 9 is set at the time of failure inspection of the first motor 101. At this time, the state command unit 93 inputs the state command signal: High to the first three-state buffer 94a, and inputs the state command signal: Low to the second three-state buffer 94b. As a result, the drive command signal (PWM signal) transmitted from the control unit 91 to the first motor 101 is transmitted to the first pre-driver 95a, and the first motor 101 is driven. On the other hand, the second three-state buffer 94b to which the state command signal: Low is input cuts off the drive command signal (PWM signal) from the control unit. As a result, the drive command signal (PWM signal) is not input to the second pre-driver 95b, and the second motor 102 is not driven. As a result, only the first motor 101 is driven.

FIG. 10 is a block diagram of the drive control device 90 at the time of executing the third mode, which drives only the second motor 102.
The third mode shown in FIG. 10 is set at the time of failure inspection of the second motor 102. At this time, the state command unit 93 inputs the state command signal: High to the second three-state buffer 94b, and inputs the second state command signal: Low to the first three-state buffer 94a. As a result, the drive command signal (PWM signal) transmitted from the control unit 91 to the second motor 102 is transmitted to the second pre-driver 95b, and the second motor 102 is driven. On the other hand, the first three-state buffer 94a to which the state command signal: Low is input cuts off the drive command signal (PWM signal) from the control unit. As a result, the drive command signal (PWM signal) is not input to the first pre-driver 95a, and the first motor 101 is not driven. As a result, only the second motor 102 is driven.

In the inspection mode of the present embodiment, first, the second mode is executed for a specified time, and the presence or absence of failure of the first motor 101 is detected. At this time, the control unit 91 monitors whether or not there is an abnormality in the output of the encoder 103. When the control unit 91 determines that the output of the encoder is abnormal, it determines that the first motor 101 has failed.

On the other hand, when it is determined that there is no abnormality in the first motor 101, the third mode is executed for a specified time and the presence or absence of failure of the second motor 102 is detected. When it is determined that the output of the encoder 103 is abnormal, it is determined that the second motor 102 has failed.

In the present embodiment, the failure inspection of the second motor 102 is performed after the failure inspection of the first motor 101, but the failure inspection of the first motor 101 is performed after the failure inspection of the second motor 102. You may go.

Further, in the motor failure determination, even if the drive command signal such as the drive current value and the PWM value generated by the control unit 91 is monitored and the motor failure is determined by comparing with the normal operation or a predetermined threshold value. Good.

Such an inspection mode may be performed at the time of the initialization operation as the initial operation performed when the device power is turned on or when the device is restored from the standby state. Further, the inspection mode may be executed at the end of paper feeding. By not executing the inspection mode during the initialization operation but executing the inspection mode only at the end of paper feeding, the preparation period at the time of startup can be shortened.

Further, the inspection mode may be executed when the feed roller 55 is temporarily stopped during paper feeding. When the inspection mode is executed when the feed roller 55 is temporarily stopped, the direction command signal (DIR) transmitted by the control unit 91 is set in the direction opposite to the direction in which the feed roller 55 is fed (rotational drive direction during normal operation). It is a direction command signal (DIR) to be driven to rotate. As a result, in the inspection mode, the first motor 101 and the second motor 102 are rotationally driven in the direction opposite to that at the time of feeding. As described above, since the one-way clutch is connected to the rotating shaft 108 of the feed roller 55, when the motors 101 and 102 are driven in reverse rotation, the driving force of the motor is not transmitted to the feed roller 55. As a result, even if the inspection mode is executed with the paper sandwiched between the feed roller 55 and the separate roller 56, the paper is not conveyed and the feeding is not affected. Further, by executing the inspection mode when the feed roller 55 is temporarily stopped, it is possible to frequently inspect the motor for failure.

Further, the feed roller 55 is configured to be detachable from the separate roller 56, and when the inspection mode is executed when the feed roller 55 is paused during paper feeding, the feed roller is provided to the separate roller 56. The inspection mode may be executed at a distance. With such a configuration, the motor can be inspected without affecting the paper sandwiched between the feed roller 55 and the separate roller 56.

Further, in the inspection mode, the second mode and the third mode are executed to inspect the operation of both the first motor 101 and the second motor 102, but only one of the motors is inspected for operation. May be good. In this case, when the operation inspection is performed on the first motor 101, it is preferable that the operation inspection is performed on the second motor 102 in the next inspection mode, and the motor to be inspected is different from the previous one. ..

Further, switching between the first mode in which all the motors are driven using the three-state buffer, which is a simple integrated circuit, the second mode in which only the first motor 101 is driven, and the third mode in which only the second motor 102 is driven. Can be done. This makes it possible to provide a drive device that can switch the operation mode with a simple and inexpensive configuration.

Further, in the present embodiment, a three-state buffer is arranged in the transmission path of each drive command signal between the control unit and each drive source, and the cutoff / transmission of the drive command signal from the control unit is switched. Not limited to this. For example, the drive command signal may be cut off / transmitted by arranging a switch instead of the three-state buffer and switching ON / OFF of the switch. The ON / OFF of such a switch may be manually performed by the user or may be controlled by the device.

Further, in the present embodiment, the encoder 103 detects the shaft angle of the motor shaft 101a of the first motor 101, but the present invention is not limited to this, and for example, the encoder 103 detects the shaft angle of the motor shaft 102a of the second motor 102. Alternatively, the axis angle of the axis 108 of the feed roller 55 may be detected.

Further, the encoder 103 may be built in the motor, or the position signal xdet and the angular velocity vdet may be generated by using the internal signal of the motor and fed back to the control unit 91. Further, both the first motor 101 and the second motor 102 are provided in the encoders, and the position signals xdet and the angular velocity vdets of a plurality of encoders are selectively or calculated by averaging and then fed back to the control unit 91. May be good. As described above, when the encoder is provided for each motor, the cost of the device is increased as compared with the case where one encoder common to each motor described above is provided. However, since the control unit that generates and transmits the drive control signal and detects the failure is one control unit common to each motor, the cost is lower and the device is smaller than the conventional technology in which the control unit is provided for each motor. Can be achieved.

FIG. 11 is a flowchart showing an example of the mode selection procedure in the present embodiment.
First, the drive control device 90 performs the above-mentioned motor failure inspection to determine whether or not there is a failed motor (S1). When there is a failed motor (Yes in S1), the drive control device 90 sends motor failure information including the fact that a motor failure has occurred from the communication network to the customer service management device via the control unit of the printer main body. Notify (S2).

After that, the drive control device 90 further determines whether or not all the motors 101 and 102 are out of order (S3), and if all the motors 101 and 102 are out of order (Yes in S3), feeds. Since the roller 55 cannot be driven, a notification (notification) is given to the user to urge maintenance or replacement of the motor, and a control unit of the printer main body is notified to stop the system (S4).

On the other hand, if the failed motor is only a part of the motors (No in S3), the feed roller 55 can be driven only by the part of the motors that have not failed. Therefore, if the first motor 101 is out of order, the third mode that uses only the second motor 102 is selected, and if the second motor 102 is out of order, the second mode that uses only the first motor 101 is selected. Is selected to operate (S6).

At this time, the paper type information and the setting of the transport speed that can be selected are limited to those that can be operated by only one motor, so if the selection is not made by the user, change to the one that can be operated. The user is notified on the touch panel through the control unit of the printer body (S5). However, if the paper type information that can be operated by one motor has already been selected and the transfer speed is switched to one that can be operated by one motor, the operation by one motor becomes possible. In such a state, only the transport speed may be automatically switched to execute the operation (second mode or third mode) with one motor without notifying the user at all. In this case, it is possible to continue using the system without making the user feel a failure as much as possible.

On the other hand, when there is no failed motor (No in S1), is the drive control device 90 capable of operating the paper type information and the transfer speed setting selected by the user through the control unit of the printer main body with only one motor? It is determined whether or not (S7, S8). That is, in this determination, either the first condition that the drive load applied to the feed roller 55, which is the same drive target, is a predetermined value ≧, or the drive load applied to the feed roller 55, which is the same drive target, is less than the predetermined value. Judge whether the second condition is satisfied.

In this determination, for example, the selected paper type information is thin paper, the transport speed is low speed mode (energy saving mode), and the operation can be performed by only one motor (that is, the second condition is satisfied). When it is determined (Yes in S7, Yes in S8), a second mode or a third mode in which driving is performed by only one motor is selected and executed (S6). For example, when the selected paper type information is thick paper or the transport speed is in the high-speed mode, and it is determined that the paper cannot be operated by only one motor (that is, the first condition is satisfied). (No in S7, No in S8) The first mode in which both of the two motors 101 and 102 drive is selected and executed (S9).

The above-mentioned flowchart is an example assuming the case where there are two motors, but the same applies even when there are three or more motors.
Further, it is preferable to determine whether to feed the paper having a low torque required for feeding in the second mode or the third mode based on the frequency of use of the motor.

In the present embodiment, as described above, it is determined whether the first condition or the second condition is satisfied based on the paper type (paper type) and the transport speed, and the first mode, the second mode, and the third mode are determined. Is selected and executed, but the present invention is not limited to this, and it may be determined whether or not the first condition or the second condition is satisfied based on other information.

For example, when a high-speed mode and a low-speed mode (power saving mode) are provided, in the high-speed mode, the feed roller is set in the first mode in order to perform the high-speed feed control that requires the speed-up control of the feed roller described above. When the 55 is driven and the low speed mode (power saving mode) is set, the feed roller 55 may be driven in the second mode or the third mode without performing the high speed feeding control.

Further, for example, in the high-speed feed control, the feed roller 55 is driven in the first mode only when the speed is increased when the feed is restarted after the feed of the next paper S2 is temporarily stopped, and in other cases, the second paper is second. The feed roller 55 may be driven in either the mode or the third mode.

FIG. 12 is a flowchart showing a flow of control during execution of the second mode or the third mode in which the feed roller 55 is driven by only one motor.
When the second mode or the third mode (here, it is assumed to be the second mode) in which the feed roller 55 is driven by only one motor is selected and executed (S6), the drive control device 90 is driven. It is monitored whether or not the driving amount (here, converted to the paper transport distance) of one of the motors (first motor 101) exceeds the specified distance (for example, 100 [m]) (S11). Then, when the paper transport distance of one motor (first motor 101) exceeds the specified distance (Yes in S11), one of the driving motors (first motor 101) is driven by the other non-driving motor. In order to switch to the motor (second motor 102), the third mode is selected and executed (S14).

At the time of this switching, the drive control device 90 refers to the failure presence / absence determination result of the other non-driving motor (second motor 102), and if the other motor (second motor 102) is not failed (2nd motor 102). S12 No), the third mode is selected and executed in order to switch to the other non-driving motor (second motor 102) (S14). If the other motor (second motor 102) is out of order (Yes in S12), the switch to the other non-driving motor (second motor 102) is not performed (S13), and the second mode is performed. Is left selected, and the driving of one of the motors (first motor 101) being driven is continued.

When the third mode is selected and switched to the other motor (second motor 102) (S14), and when the paper transport distance of the other motor (second motor 102) after switching exceeds the specified distance (S11). ), This time, the second mode is selected and the original motor (first motor 101) is switched to (S14).

By alternately driving the two motors 101 and 102 one by one in this way, only one of the two motors 101 and 102 is not overused, and the two motors 101 and 102 The amount of drive can be equalized. As a result, the period until one of the two motors fails can be extended, and the life can be extended.

In the present embodiment, the two motors 101 and 102 are used alternately to equalize the driving amounts of the two motors 101 and 102. In this case, the two motors 101 and 102 are used at the same time. There is a high possibility that it will break down. In such a case, the drive amounts of the two motors 101 and 102 may be made non-uniform. For example, when driving only one motor, only the second mode for driving the first motor 101 may always be selected.

FIG. 13 is an explanatory diagram showing the display contents of the touch panel which is the printer operation unit when the user selects the paper type information.
When the user displays the paper type selection screen as shown in FIG. 13 on the touch panel, the user can select and determine the paper type of the paper to be used from a plurality of paper types on the paper type selection screen. it can. In the example of FIG. 13, the paper types that can be driven by only one motor are "My Paper" and "Thin Paper".

FIG. 14 is an explanatory diagram showing the display contents of the touch panel when the user selects the transport speed.
When the transport speed setting screen as shown in FIG. 14 is displayed on the touch panel, the user can select and determine the transport speed to be used from a plurality of transport speeds on the transport speed setting screen. In the example of FIG. 14, the transport speed that can be driven by only one motor is only "low speed".

FIG. 15 is an explanatory diagram showing the display contents of the touch panel displayed when notifying the user of the motor failure.
The example of FIG. 15 is an image example displayed on the touch panel when the first motor 101 (motor 1) of the two motors 101 and 102 for driving the feed roller 55 fails. This display informs the user which motor has failed and encourages maintenance and replacement of the motor. Further, in this display, it is notified that the paper type and the transport speed that can be used are limited when the printer is continuously used by using only one motor that has not failed, and is shown in FIGS. 13 and 14. On the screen, you will be guided to select a limited paper type and transport speed.

The display indicating that all the motors 101 and 102 have failed indicates which motor has failed and prompts the maintenance and replacement of the motors, but does not indicate the continuation of use of the printer.

What has been described above is an example, and each of the following aspects produces a unique effect.
[First aspect]
The first aspect includes control means (for example, control unit 91, mode switching unit, etc.) for controlling a plurality of drive sources (for example, two motors 101 and 102) for driving the same drive target (for example, feed roller 55). In the drive control devices 90, 90', the control means drives the same drive target with the plurality of drive sources in a state in which the same drive target can be driven by the plurality of drive sources. Select a drive mode (for example, first mode) or a second drive mode (for example, second mode or third mode) in which the same drive target is driven by a part of the plurality of drive sources. It is characterized by executing.
According to this aspect, even in a state where the same drive target can be driven by a plurality of drive sources, a second drive mode in which the same drive target is driven by a part of the drive sources among the plurality of drive sources is selected. Can be executed. Therefore, when it is not necessary to drive the same drive target with a plurality of drive sources, the drive of other drive sources can be stopped by selecting and executing the second drive mode, which saves energy. Can be achieved, and the life of the other drive source can be extended.

[Second aspect]
In the second aspect, in the first aspect, the control means sets the first drive mode when the first condition (for example, thick paper, high speed mode) in which the drive load applied to the same drive target is equal to or more than a predetermined value is satisfied. It is characterized in that the second drive mode is selected when the second condition (for example, thin paper, low speed mode) in which the drive load applied to the same drive target is less than the predetermined value is satisfied.
According to this, in a situation where the drive load is large, the drive is stabilized by selecting and executing the first drive mode in which the same drive target is driven by a plurality of drive sources, while the drive load is small. Then, it can be said that energy saving is realized by selecting and executing the second drive mode in which the drive target is driven by only a part of the drive sources.

[Third aspect]
In the third aspect, in the second aspect, the control means uses the type identification information (for example, paper type information) of the transported object (for example, transfer paper S) conveyed by the same driving object or the driving of the same driving object. It is characterized in that it is determined whether or not the first condition or the second condition is satisfied based on the speed information (for example, the information of the transport speed).
According to this, it is possible to easily determine whether the drive load is large or small.

[Fourth aspect]
A fourth aspect is characterized in that, in any one of the first to third aspects, the control means switches the drive source to be driven according to a predetermined switching condition during execution of the second drive mode. ..
According to this, it is possible to prevent the part of the drive sources from having a short life without overusing only a part of the drive sources.

[Fifth aspect]
A fifth aspect is characterized in that, in the fourth aspect, the predetermined switching condition is a condition that the driving source to be driven is switched for each predetermined driving amount (for example, paper transport distance).
According to this, each usage amount (driving amount) of the plurality of drive sources can be equalized, and the life of the drive device can be extended.

[Sixth aspect]
A sixth aspect is, in any one of the first to fifth aspects, when the control means is in a state in which any of the plurality of drive sources cannot be driven (for example, a failure state). It is characterized in that the same drive target is driven by the remaining drive sources.
According to this, downtime can be reduced.

[7th aspect]
A seventh aspect, in the sixth aspect, is characterized in that the control means performs a notification process for notifying the user that the driveless state has been reached.
According to this, it is possible to prompt the user to replace or maintain the motor that has become undriveable, and it is possible to recover the motor at an early stage.

[8th aspect]
The eighth aspect is characterized in that, in the sixth or seventh aspect, the control means performs a notification process for notifying the management device via the communication network that the driveless state has been reached. Is what you do.
According to this, it becomes possible to recover earlier.

[9th aspect]
A ninth aspect is a drive device 100 including a plurality of drive sources that drive the same drive object, and is characterized by including the drive control device according to any one of the first to eighth aspects.
According to this, in a situation where it is not necessary to drive the same drive target with a plurality of drive sources, the drive of another drive source can be stopped by selecting and executing the second drive mode. It is possible to achieve energy saving, and it is possible to extend the life of the other drive source.

[10th aspect]
A tenth aspect is a sheet conveying device (for example, a paper feeding device 50), which is characterized by including the driving device of the ninth aspect.
According to this, in a situation where it is not necessary to drive the same drive target with a plurality of drive sources, the drive of another drive source can be stopped by selecting and executing the second drive mode. It is possible to provide a sheet transfer device capable of achieving energy saving and extending the life of the other drive source.

[11th aspect]
The eleventh aspect is an image forming apparatus (for example, a printer 500), characterized in that the driving device of the ninth aspect is provided.
According to this, in a situation where it is not necessary to drive the same drive target with a plurality of drive sources, the drive of another drive source can be stopped by selecting and executing the second drive mode. It is possible to provide an image forming apparatus capable of achieving energy saving and extending the life of the other drive source.

1: Image-creating unit 2: Photoreceptor 3: Cleaning device 4: Charging device 5: Developing device 6: Intermediate transfer unit 6a: Intermediate transfer belt 7: Primary transfer rollers 9A to 9D: Paper cassettes 10A, 10B: Calling rollers 11A , 11B: Separation roller 12A, 12B: Conveying roller pair 14: Secondary transfer unit 14a: Secondary transfer roller 15: Fixing device 30: Double-sided unit 40: Toner cartridge 50: Paper feed device 51: Paper feed tray 52: Paper guide 53: Paper cassette bottom plate 54: Calling roller 55: Feed roller 56: Separate roller 58: Grip roller 60: Paper ejection tray 80: Exposure device 90, 90': Drive control device 91: Control unit 92: Mode switching unit 93: Status Command unit 100: Drive device 101: First motor 102: Second motor 103, 104: Encoder 105: First gear 106: Second gear 107: Output gear 108: Rotating shaft 200: Image forming unit 300: Paper feeding unit 400 : Mounting part 500: Printer

Japanese Unexamined Patent Publication No. 2006-42483

Claims (11)

A drive control device including a control means for controlling a plurality of drive sources that drive the same drive target.
The control means has a first drive mode in which the same drive target is driven by the plurality of drive sources in a state where the same drive target can be driven by the plurality of drive sources, or the same drive target. A drive control device characterized in that a second drive mode driven by a part of the plurality of drive sources is selected and executed. In the drive control device according to claim 1,
The control means selects the first drive mode when the first condition that the drive load applied to the same drive target is equal to or greater than a predetermined value is satisfied, and the drive load applied to the same drive target is less than the predetermined value. A drive control device, characterized in that the second drive mode is selected when the second condition is satisfied. In the drive control device according to claim 2,
The control means determines whether or not the first condition or the second condition is satisfied based on the type identification information of the transported object conveyed by the same drive target or the drive speed information of the same drive target. A drive control device characterized by In the drive control device according to any one of claims 1 to 3,
The control means is a drive control device, characterized in that, during execution of the second drive mode, the drive source to be driven is switched according to a predetermined switching condition. In the drive control device according to claim 4,
The drive control device is characterized in that the predetermined switching condition is a condition that the driving drive source to be driven is switched for each predetermined driving amount. In the drive control device according to any one of claims 1 to 5,
The control means is a drive control device, characterized in that, when any of the plurality of drive sources becomes undriveable, the same drive target is driven by the remaining drive sources. .. In the drive control device according to claim 6,
The control means is a drive control device that performs a notification process for notifying the user that the drive cannot be driven. In the drive control device according to claim 6 or 7.
The control means is a drive control device that performs a notification process for notifying the management device of the fact that the drive cannot be driven. A drive device having a plurality of drive sources for driving the same drive target.
A drive device including the drive control device according to any one of claims 1 to 8. A sheet transfer device including the drive device according to claim 9. An image forming apparatus including the driving device according to claim 9.

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