JP7200592B2 - IMAGE FORMING APPARATUS, IMAGE FORMING APPARATUS CONTROL METHOD, AND IMAGE FORMING APPARATUS CONTROL PROGRAM - Google Patents

Description

The present disclosure relates to an image forming apparatus, an image forming apparatus control method, and an image forming apparatus control program, and in particular, an image forming apparatus suitable for failure detection, an image forming apparatus control method, and an image forming apparatus Concerning the control program.

As a paper feed tray for an image forming apparatus, a push-up plate is arranged on the bottom surface, and the paper stacked thereon is pushed up by the push-up plate so that the uppermost paper comes into contact with the paper feed roller. things are commonly known. In the paper feed tray having such a configuration, the push-up plate is pushed up by the lift-up drive, and the upper limit sensor installed in the paper feed tray detects that the uppermost paper comes into contact with the paper feed roller.

On the other hand, when an abnormality occurs in the lift-up of the lift-up plate of the paper feed tray, it is necessary to identify the defective parts that caused the abnormality, such as the lift-up motor, the connecting gear between the lift-up plate and the lift-up motor, the upper limit sensor, etc. is important for reducing maintenance time for service personnel and preventing unnecessary parts replacement.

Japanese Patent Application Laid-Open No. 2002-200001 discloses an image forming apparatus that controls the elevation of a plurality of paper feed trays by one lift-up motor and an electromagnetic clutch provided for each paper feed tray. In this image forming apparatus, in order to reduce the torque of the lift-up motor, the elevation control of each paper feed tray is performed at exclusive timing.

Further, Japanese Patent Application Laid-Open No. 2002-200003 discloses an image forming apparatus that detects a lift-up abnormality using a failure detection sensor of a paper feed tray. In this image forming apparatus, the failure state is recorded, and if the failure state continues in the standby state after the power is turned on, the insertion/removal of the paper feed tray is displayed.

JP 2008-127117 A Japanese Patent Application Laid-Open No. 2008-110861

In the image forming apparatus disclosed in Patent Document 2, each paper feed tray is provided with a sensor for detecting a failure. Further, Japanese Patent Application Laid-Open No. 2002-200000 describes sharing a drive unit among the paper feed trays, but does not particularly consider failure detection. In order to reliably detect failures in a plurality of paper feed trays, manufacturing costs cannot be reduced if a configuration for detecting failures is provided for each of the plurality of paper feed trays.

This disclosure has been made to solve the above-described problems, and one of the purposes of this disclosure is to provide an image forming apparatus capable of reliably detecting a failure of a paper feeding device while reducing manufacturing costs. An object of the present invention is to provide a control method for a forming apparatus and a control program for an image forming apparatus.

In order to achieve the above object, according to one aspect of the present disclosure, an image forming apparatus includes: a plurality of sheet feeding devices; and a control unit for controlling the At least part of the failure confirmation unit is shared by a plurality of sheet feeders. The failure confirmation unit confirms a failure when the control unit is operating one of the plurality of paper feeders.

Preferably, the paper feeder includes a drive unit for moving the paper stored in the paper feeder to a paper feedable position. The failure confirmation unit includes a drive failure confirmation unit that confirms a failure of the drive unit. At least a portion of the drive failure confirmation unit is shared by a plurality of paper feeders.

More preferably, the paper feeding device includes a paper detection unit that detects whether or not the paper stored in the paper feeding device has been moved to a position where paper can be fed. The failure confirmation unit includes a detection failure confirmation unit that confirms failure of the paper detection unit. At least a portion of the detection/failure confirmation unit is shared by a plurality of sheet feeding devices. More preferably, the failure confirmation unit confirms failure of the paper detection unit before failure of the drive unit.

Preferably, the failure confirmation unit confirms the failure at a timing when the operations of the plurality of paper feeders do not overlap. Preferably, the control section prohibits the operation of other sheet feeding devices when the failure confirmation section confirms that the sheet feeding device is malfunctioning.

Preferably, when confirming failures in at least two of the plurality of paper feeders, the controller sequentially operates the two or more paper feeders for which failures are to be confirmed. The failure confirmation unit sequentially confirms failures of the paper feeders operated by the control unit.

Preferably, the control unit can execute control to feed paper from one of the paper feeders. The failure confirmation unit prohibits failure confirmation of the paper feeding device when the control unit is executing paper feeding control.

Preferably, when paper is replenished in the paper feeder, the control unit moves the paper to a position where paper can be fed even if the failure confirmation unit confirms that another paper feeder is malfunctioning. control the drive unit to

According to another aspect of the present disclosure, a control method includes a plurality of paper feeders, a failure confirmation section for checking failure of the plurality of paper feeders, and a control section for controlling the plurality of paper feeders. A control method for a forming apparatus. At least part of the failure confirmation unit is shared by a plurality of sheet feeders. The control method includes a step in which the control unit operates one of the plurality of paper feeders, and a step in which the failure confirmation unit detects a failure while the control unit is operating one of the plurality of paper feeders. and controlling to confirm.

According to still another aspect of the present disclosure, a control program includes a plurality of paper feeders, a failure confirmation section that checks for failures in the plurality of paper feeders, and a control section that controls the plurality of paper feeders. A control program executed by a control unit in an image forming apparatus. At least part of the failure confirmation unit is shared by a plurality of sheet feeders. The control program causes the control unit to perform the steps of operating one of the plurality of paper feeders, and controlling to confirm a failure while operating one of the plurality of paper feeders. let it run.

According to this disclosure, it is possible to provide an image forming apparatus, a control method for the image forming apparatus, and a control program for the image forming apparatus that can reliably detect a failure of the paper feeding device while reducing manufacturing costs. can.

1 is a diagram showing a schematic configuration of a printer according to an embodiment; FIG. 4 is a diagram showing a schematic configuration of a paper feed tray mechanism; FIG. 3 is a control block diagram of the printer according to the embodiment; FIG. 3 is a control block diagram of the paper feed tray according to the embodiment; FIG. 4 is a flow chart showing the flow of processing according to the first embodiment; It is a flow chart which shows a flow of lift up control processing of a 1st embodiment. 4 is a flow chart showing the flow of faulty component identification control processing according to the first embodiment; It is a flow chart which shows a flow of lift-up control processing of a modification of a 1st embodiment. 9 is a flow chart showing the flow of processing according to the second embodiment; FIG. 11 is a flow chart showing the flow of faulty component identification control processing according to the second embodiment; FIG.

Embodiments of the present disclosure will be described below with reference to the drawings. In the following description, identical parts and components are given identical reference numerals. Their names and functions are also the same. A detailed description thereof will therefore not be repeated.

In the present embodiment, a case where the image forming apparatus according to the present disclosure is a tandem digital color printer (hereinafter referred to as a printer) will be described.

FIG. 1 is a diagram showing a schematic configuration of a printer 10 according to this embodiment. Referring to FIG. 1, printer 10 includes transfer belt 12 as an intermediate transfer body, imaging units 20Y, 20M, 20C and 20K, temporary transfer rollers 30Y, 30M, 30C and 30K, and secondary transfer roller 34. , a cleaner blade 38 , paper feed trays 60 and 70 , a timing roller pair 48 , a fixing unit 50 and a paper output tray 11 .

The transfer belt 12 is an endless belt, supported by rollers 14 and 16 so as not to loosen, and rotated counterclockwise in FIG. 1 in the direction of arrow A at a predetermined speed. .

Imaging units 20Y, 20M, 20C, and 20K (hereinafter collectively referred to as imaging units 20) contain basic color toners of yellow (Y), magenta (M), cyan (C), and black (K). , and is positioned below the lower horizontal portion of the transfer belt 12 . Imaging unit 20 includes photoreceptor drum 22 , charger 24 , print head 26 , developer 28 , primary transfer roller 30 and cleaner 32 . A charger 24 , a print head 26 , a developer 28 , a primary transfer roller 30 and a cleaner 32 are provided around the photosensitive drum 22 . The imaging unit 20 is configured to be movable between a position (pressure contact position) where the photosensitive drum 22 contacts the transfer belt 12 (pressure contact position) and a position where it does not contact (separate position) by a pressure contact/separation motor (not shown). .

The charger 24 uniformly charges the surface of the photosensitive drum 22 . The print head 26 outputs a laser beam to the photosensitive drum 22 based on each color data constituting the image data, and exposes the uniformly charged surface of the photosensitive drum 22 according to the image data to statically. Forms an electrostatic latent image. The developing device 28 develops the electrostatic latent image formed on the surface of the photosensitive drum 22 with toner of each color to form a toner image. The primary transfer roller 30 faces the photosensitive drum 22 with the transfer belt 12 interposed therebetween, and electrostatically attracts the toner image formed on the surface of the photosensitive drum 22 to primarily transfer it onto the transfer belt 12 . The cleaner 32 collects and cleans the toner remaining on the surface of the photosensitive drum 22 after the primary transfer.

The secondary transfer roller 34 faces the roller 14 with the transfer belt 12 interposed therebetween. (separated position). The secondary transfer roller 34 is moved to the pressure contact position and is applied with a high positive transfer voltage, thereby electrostatically transferring the toner image formed on the transfer belt 12 onto the paper conveyed to the transfer area 36 . secondary transfer by attracting

The cleaner blade 38 is pressed against the portion of the transfer belt 12 supported by the roller 16 , scrapes the toner remaining on the transfer belt 12 after the secondary transfer, and collects it in the waste toner box 40 .

The paper feed trays 60 and 70 are detachably arranged in a two-stage configuration (the paper feed tray 60 is the upper stage and the paper feed tray 70 is the lower stage) in the lower part of the printer 10, and the paper sheets S, which are recording media, are stacked and stored. do. The details of the paper feed trays 60 and 70 will be described later. The paper sheets S accommodated in the paper feed trays 60 and 70 are sent to the transport path 46 one by one from the uppermost one by the rotation of the paper feed rollers 62 and 72 . The transport path 46 extends from the paper feed trays 60 and 70 through the nip portion of the timing roller pair 48 , the transfer area 36 and the fixing unit 50 to the paper discharge tray 11 . Sheets S sent from the sheet feeding trays 60 and 70 are fed to the transfer area 36 in synchronization with the toner image on the transfer belt 12 by the timing roller pair 48, and the toner image is secondarily transferred in the transfer area 36. be done. After that, the secondarily-transferred toner image is fixed on the sheet S by heat melting by the fixing unit 50 , and the sheet S with the toner image fixed thereon is discharged to the discharge tray 11 .

FIG. 2 is a diagram showing a schematic configuration of the mechanism of the paper feed tray 60. As shown in FIG. In FIG. 2, the paper feed tray 60 will be described as an example, but the paper feed tray 70 has the same configuration. 1 and 2, paper feed tray 60 includes a push-up plate 61, a paper feed roller 62, regulation plates 63A and 63B, a lift-up motor (not shown), and an upper limit sensor 64. As shown in FIG. The regulation plate 63</b>A regulates the position of the sheets S stacked on the push-up plate 61 in the width direction, and is movable in the width direction of the paper feed tray 60 . The regulation plate 63B regulates the position of the trailing edge of the sheet S and is movable in the sheet feeding direction of the sheet feeding tray 60 .

When the sheet S is stacked on the push-up plate 61 and the paper feed tray 60 is inserted into the printer 10, the lift-up motor is rotationally driven, and the push-up plate 61 is raised and held with the support shaft 61A as the fulcrum. The sheet S contacts the upper limit sensor 64, and the light shielding plate shields the light from the photointerrupter, thereby detecting the upper limit position. When the upper limit position of the sheet S is detected, the lift-up motor is stopped and the push-up plate 61 stops rising. The position of this push-up plate 61 is the paper feeding position. On the other hand, when the paper feed tray 60 is pulled out from the printer 10 , the hold of the push-up plate 61 is released, and the push-up plate 61 is lowered to the bottom surface of the paper feed tray 60 . The position of this push-up plate 61 is the standby position. Failure of the lift-up motor can be detected by monitoring the motor driver overcurrent signal during rotation. Further, the upper limit sensor failure can be detected by monitoring the sensor logic when an LED (light emitting diode) of the photointerrupter is turned on/off.

FIG. 3 is a control block diagram of the printer 10 of this embodiment. Referring to FIG. 3, printer 10 includes control unit 100, image forming unit 110, operation panel unit 130, upper paper feed tray 60, lower paper feed tray 70, conveying unit 140, and an ejection unit. and a paper section 150 .

The control unit 100 includes a CPU (Central Processing Unit) for controlling the entire printer 10, a ROM (Read Only Memory) for storing programs to be executed by the control unit 100, and a program by the control unit 100. RAM (Random Access Memory) used as a work area required for execution. A hard disk drive or memory card may be used as an auxiliary storage device for supplementing the storage area of the RAM. Also, the control unit 100 transmits and receives data to and from an external device such as a PC via a communication network.

Operation panel unit 130 includes a display, a plurality of operation buttons for causing printer 10 to execute predetermined functions, and a touch pad superimposed on the display. The display is composed of a liquid crystal display device (hereafter referred to as "LCD" (Liquid Crystal Display)) or the like, and displays an image received from the control unit 100, which indicates the state of the printer 10 and the operation buttons of the touch pad. . An operation signal indicating the operation content input to the printer 10 is transferred to the control unit 100 by operating the operation button and the touch pad.

The image forming unit 110 has the components shown in FIG. The image forming section 110 performs primary transfer and secondary transfer of the toner image formed on the photosensitive drum 22, as shown in FIG. The transport section 140 transports the paper from the transport path 46 to the fixing unit 50 through the pair of timing rollers 48 . The paper discharge section 150 discharges the paper that has passed through the fixing unit 50 to the paper discharge tray 11 .

The paper feed tray 60 includes a push-up plate 61, a paper feed roller 62, regulation plates 63A and 63B, an upper limit sensor 64, and a lift-up motor 65, as shown in FIGS. The paper feed tray 70 also includes a configuration similar to that of the paper feed tray 60 .

FIG. 4 is a control block diagram of the paper feed trays 60 and 70 of this embodiment. Referring to FIG. 4, the upper upper limit sensor 64 is composed of a photointerrupter, and specifically includes an infrared LED 64A that emits infrared light and a phototransistor 64B that detects the light from the infrared LED 64A. Like the upper limit sensor 64, the lower upper limit sensor 74 also includes an infrared LED 74A and a phototransistor 74B.

Infrared LED 64A and infrared LED 74A are connected to output port 102A of control unit 100 via signal line 104A, and share signal line 104A. Infrared LED 64A and infrared LED 74A emit infrared light in accordance with the ON-state upper limit sensor (upper/lower) LED output signal output from control unit 100 to light up, and the OFF-state upper limit sensor (upper/lower) LED is turned on. It turns off according to the output signal. The on-state signal is, for example, a high-level (eg, 5V) signal. An off-state signal is, for example, a low-level (eg, 0 V) signal.

The phototransistor 64B is connected to the input port 103A of the control section 100 and the signal line 104B. The phototransistor 74B is connected to the input port 103B of the control section 100 via a signal line 104C. The light blocking plate is configured to be movable between a position that blocks light incident on the phototransistor 64B from the infrared LED 64A and a position that does not block the light. The light blocking plate is moved to a position where the light is blocked by the paper S when the paper S is lifted by the push-up plate 61 and reaches the upper limit, and returns to a position where the light is not blocked when the paper S is not moved. When the light shielding plate blocks the light from the infrared LED 64A, the phototransistor 64B outputs an on-state upper limit sensor (upper) detection signal indicating that the sheet S has reached the upper limit, while the light is not blocked. When the sheet S has not reached the upper limit, an off-state upper limit sensor (upper stage) detection signal is output. Like the phototransistor 64B, the phototransistor 74B also outputs the upper limit sensor (lower stage) detection signal in the ON state or the OFF state.

In this way, the paper feed trays 60 and 70 can separately detect that the number of sheets S has reached the upper limit. However, when the upper limit sensor (upper/lower stage) LED output signal is turned off in order to detect a failure of one of the upper limit sensors 64, 74, both the upper and lower infrared LEDs 64A, 74A are extinguished. Since the infrared LED that does not detect the failure is also extinguished, even if the sheet S has not reached the upper limit, an ON-state upper limit sensor detection signal indicating that the upper limit has been reached is output. This state is called a fixed upper limit state.

The upper lift-up motor 65 is connected to channel 1 of the motor driver IC 101 via signal lines 104G and 104H. The lower lift-up motor 75 is connected to channel 2 of the motor driver IC 101 by signal lines 104J and 104K. The motor driver IC 101 is connected to the output port 102B of the control unit 100 via a signal line 104D, to the output port 102C via a signal line 104F, and to the input port 103C via a signal line 104E.

The control unit 100 outputs a lift-up motor (upper stage) drive signal for driving the lift-up motor 65 from the output port 102B to the motor driver IC 101 via the signal line 104D. Motor driver IC 101 transmits a motor drive signal for driving upper lift-up motor 65 from channel 1 to lift-up motor 65 via signal line 104G in accordance with a lift-up motor (upper) drive signal from control unit 100. output to The lift-up motor 65 is driven according to this motor drive signal. When detecting overcurrent, the lift-up motor 65 outputs an overcurrent signal to channel 1 of the motor driver IC 101 via the signal line 104H. Motor driver IC 101 outputs a lift-up motor (upper/lower stage) over-current signal to input port 103C of control unit 100 via signal line 104E according to the over-current signal from lift-up motor 65 .

Thus, the motor driver IC 101 is controlled by the control unit 100 to drive the lift-up motor 65 using channel 1, detect an abnormality of the lift-up motor 65, and transmit it to the control unit 100. FIG. Similarly, the motor driver IC 101 is controlled by the control unit 100 to drive the lower lift-up motor 75 using channel 2, detect an abnormality of the lift-up motor 75, and transmit the detected abnormality to the control unit 100.

Thereby, the lift-up motors 65 and 75 are independently controlled. However, a signal indicating an abnormality of the plurality of lift-up motors 65 and 75 (here, an overcurrent signal) is input to the control section 100 through one signal line 104E. Therefore, if a plurality of lift-up motors 65, 75 are driven at the same time, it cannot be determined which lift-up motor 65, 75 the overcurrent signal is caused by.

As shown in FIG. 4, by sharing at least a part of the configuration for checking the failure of the printer 10 with the plurality of paper feed trays 60 and 70, the number of input ports and output ports used in the control unit 100 can be reduced. can be reduced and the number of parts can be reduced, so the manufacturing cost can be reduced. However, as described above, problems occur in the detection of failures.

Therefore, the printer 10 according to this disclosure includes a plurality of paper feed trays 60 and 70, and a failure check section (control section 100, upper limit sensors 64 and 74, lift-up motor 65) that checks failure of the plurality of paper feed trays 60 and 70. , 75, motor driver IC 101, signal lines 104A to 104K), and a control unit 100 for controlling a plurality of paper feed trays. At least a portion of the failure checking section is shared by the plurality of paper feed trays 60 and 70 . The failure confirmation unit confirms a failure when the control unit 100 is operating one of the plurality of paper feed trays 60 and 70 . As a result, failures of the paper feed trays 60 and 70 can be reliably detected while reducing manufacturing costs.

[First embodiment]
FIG. 5 is a flow chart showing the flow of processing in the first embodiment. Referring to FIG. 5, the processing shown in FIG. 5 is periodically executed. The control unit 100 initializes the faulty component identification flag to an off state (step S1). The faulty component identification flag is a flag indicating that the faulty component identification control process is to be executed if it is on.

The control unit 100 determines whether or not one of the plurality of paper feed trays 60 and 70 has been inserted into the printer 10 (step S2). If it is determined that one of the plurality of paper feed trays 60 and 70 has been inserted (YES in step S2), the control unit 100 confirms whether faulty parts are being identified for other paper feed trays (step S3). If it is determined that the faulty component is being identified (YES in step S3), the control unit 100 waits until the faulty component is identified. As a result, erroneous detection of an overcurrent signal due to simultaneous driving of the lift-up motors 65 and 75 can be prevented. Further, erroneous detection of the upper limit sensor detection signal due to the infrared LEDs 64A, 74A of the upper limit sensors 64, 74 being turned off can be prevented.

If it is determined that the failure component has been identified (YES in step S3), the control unit 100 determines whether or not the failure component identification flag is on, thereby determining whether it is necessary to identify the failure component. (step S4). If it is determined that the faulty part identification flag is off and the faulty part does not need to be identified (NO in step S4), the control unit 100 performs normal lift-up control of the inserted paper feed tray ( step S5).

Next, the control unit 100 determines whether or not a lift-up abnormality has occurred during the lift-up control (step S6). If it is determined that a lift-up abnormality has occurred (YES in step S6), the control unit 100 sets the faulty part identification flag to ON (step S7), removes and inserts the paper feed tray, and sets the paper S incorrectly. A message is displayed on the operation panel unit 130 to prompt the user to confirm whether or not there is any error (step S8). The controller 100 determines whether or not the paper feed tray has been pulled out (step S9). If it is determined that the paper feed tray has been pulled out (YES in step S9), the control unit 100 determines again whether or not the paper feed tray has been inserted (step S2).

If it is determined that a paper feed tray has been inserted (YES in step S2) and it is determined that other paper feed trays are not being identified as faulty parts (NO in step S3), the faulty part identification flag is on ( If it is determined to be YES in step S4), the control section 100 determines whether or not printing is being performed from another paper feed tray (step S10). If it is determined that printing is being performed from another paper feed tray (YES in step S10), control unit 100 waits for the end of printing. During printing, each paper feed tray must be lifted so that the uppermost portion of the paper S is always placed at the paper feed position. If it is determined that printing has ended (NO in step S10), a faulty part identification control process is executed (step S11).

FIG. 6 is a flow chart showing the flow of lift-up control processing according to the first embodiment. This lift-up control process is called and executed at step S5 in FIG. Referring to FIG. 6, control unit 100 first initializes the lift-up abnormal state (step S5-1). Next, the control section 100 drives the lift-up motor (step S5-2).

The control unit 100 determines whether or not a predetermined abnormal lift-up time has elapsed (step S5-3). If it is determined that the abnormal lift-up time has not elapsed (NO in step S5-3), the control unit 100 receives an on-state upper limit sensor detection signal indicating that the sheet S has reached the upper limit from the upper limit sensor. (step S5-4). When determining that the upper limit sensor signal indicating that the upper limit has been reached has not been received (NO in step S5-4), control unit 100 repeats steps S5-3 and S5-4.

When determining that the upper limit sensor signal indicating that the upper limit has been reached has been received (YES in step S5-4), the control unit 100 determines that the paper S has reached the paper feed position, and stops the lift-up motor. (step S5-5).

If it is determined that the abnormal lift-up time has elapsed by the time the upper limit sensor signal indicating that the upper limit has been reached is received (YES in step S5-3), the control unit 100 indicates that the abnormal lift-up state has occurred. A flag is set (step S5-6), and the lift-up motor is stopped (step S5-5). After step S5-5, the control unit 100 returns the process to be executed to the caller process of the lift-up control process.

FIG. 7 is a flow chart showing the flow of faulty component identification control processing according to the first embodiment. This faulty component identification control process is called and executed at step S11 in FIG. Referring to FIG. 7, control unit 100 first turns off the infrared LED of the upper limit sensor in order to detect failure of the upper limit sensor (step S11-1). As described above, when the infrared LED is turned off, the upper limit sensor is in a fixed upper limit state. The control unit 100 monitors the upper limit sensor while the upper limit is fixed, and determines whether or not the phototransistor outputs an ON-state upper limit sensor detection signal indicating that the sheet S has reached the upper limit (step S11-2). If it is determined that the ON state upper limit sensor detection signal is not output (NO in step S11-2), it is determined that the upper limit sensor is faulty (step S11-5), and this faulty component identification control process is executed. Terminate and return the processing to be performed to the caller.

If it is determined that the ON state upper limit sensor detection signal is output (YES in step S11-2), the control unit 100 lights the infrared LED of the upper limit sensor (step S11-3). The control unit 100 determines whether or not an off-state upper limit sensor detection signal indicating that the sheet S has not reached the upper limit is output from the phototransistor (step S11-4). In order for the user to check that the sheet S is set incorrectly immediately before, the paper feed tray is removed and inserted, and the hold of the push-up plate is released, and the push-up plate is lowered to the bottom surface of the paper feed tray. Therefore, the paper S should not have reached the upper limit. If it is determined that the upper limit sensor detection signal in the off state is not output (NO in step S11-4), the control unit 100 determines that the upper limit sensor is faulty (step S11-5), and Terminates the component specific control process and returns the process to be executed to the caller.

Next, in order to detect failure of the lift-up motor, the control unit 100 drives the lift-up motor (step S11-6). The control unit 100 monitors the overcurrent signal of the lift-up motor and determines whether or not there is an abnormality in the lift-up motor (step S11-7).

If it is determined that there is no abnormality in the lift-up motor (NO in step S11-7), the control unit 100 determines whether or not a predetermined lift-up abnormality time has elapsed (step S11-9). If it is determined that the abnormal lift-up time has not passed (NO in step S11-9), the control unit 100 receives an on-state upper limit sensor detection signal indicating that the sheet S has reached the upper limit from the upper limit sensor. (step S11-11). When determining that the upper limit sensor signal indicating that the upper limit has been reached has not been received (NO in step S11-11), control unit 100 repeats steps S11-7, S11-9 and S11-11.

When determining that the upper limit sensor signal indicating that the upper limit has been reached has been received (YES in step S11-11), the control unit 100 determines that the paper S has reached the paper feed position, and stops the lift-up motor. (step S11-12).

If it is determined that an abnormality has been detected by the time the upper limit sensor signal indicating that the upper limit has been reached is received (YES in step S11-7), the control unit 100 determines that the lift-up motor is out of order ( Step S11-8), the lift-up motor is stopped (step S11-12), and the processing to be executed is returned to the caller of this processing.

If it is determined that the lift-up abnormal time has elapsed by the time the upper limit sensor signal indicating that the upper limit has been reached is received (YES in step S11-9), the control unit 100 controls the lift-up mechanism (for example, the lift-up plate and The connection gear of the lift-up motor) is determined to be abnormal (step S11-10), and the lift-up motor is stopped (step S11-12). Returns the process to be executed to the process that called this process.

[Modification of First Embodiment]
FIG. 8 is a flow chart showing the flow of lift-up control processing according to a modification of the first embodiment. Referring to FIG. 8, the description of the parts common to FIG. 6 will not be repeated. Steps S5-21 and S5-22 are the same as steps S5-1 and S5-2 in FIG.

After step S5-2, it is determined whether or not the lift-up motor is driven for another paper feed tray (step S5-23). If it is determined that the lift-up motors of the other paper feed trays are not driven (NO in step S5-23), the control unit 100 monitors the overcurrent signal of the lift-up motors and detects an abnormality in the lift-up motors. (step S5-24). If it is determined that there is no abnormality in the lift-up motor (NO in step S5-24), the control section 100 executes the processes from step S5-26 onward. The processing after step S5-26 is the same as the processing after step S5-3 in FIG.

If it is determined that an abnormality has been detected before the upper limit sensor signal indicating that the upper limit has been reached (YES in step S5-24), the control unit 100 determines that the lift-up motor is out of order ( Step S5-25), the lift-up motor is stopped (step S5-29), and the process to be executed is returned to the caller of this process.

If it is determined that the lift-up motors of other paper feed trays are driven (YES in step S5-23), it is determined in which lift-up motor the abnormality has occurred, as shown in FIG. Since it is not possible, the control unit 100 skips the process of step S5-24 and executes the process of step S5-26.

[Second embodiment]
In the first embodiment, as shown in FIG. 5, the lift-up control process is not executed when faulty parts are being identified for other paper feed trays. In the second embodiment, since it is rare for a plurality of parts to fail at the same time, the lift-up control process is allowed to be executed at the timing when a plurality of paper feed trays overlap.

FIG. 9 is a flow chart showing the flow of processing in the second embodiment. Referring to FIG. 9, when it is determined that one of the plurality of paper feed trays 60 and 70 has been inserted into printer 10 (step S22), control unit 100 determines that the other paper feed tray is a malfunctioning part. A lift-up control process is executed regardless of whether it is in the middle or not (step S5). Also, regardless of whether or not printing is being performed from another paper feed tray, the faulty component identification control process is executed (step S28). Other than these processes, the processes are the same as those shown in FIG.

FIG. 10 is a flow chart showing the flow of faulty component identification control processing according to the second embodiment. The control unit 100 first confirms whether or not faulty parts are being identified for other paper feed trays (step S28-1). If it is determined that the faulty part is being identified (YES in step S28-1), the control unit 100 waits for the end of faulty part identification. If it is determined that the faulty part has been identified (NO in step S28-1), the lift-up motor is driven (step S28-2).

The control unit 100 determines whether or not the lift-up motor is driven by the lift-up control in another paper feed tray (step S28-3). If it is determined that the lift-up motors of other paper feed trays are being driven (YES in step S28-3), control unit 100 determines in step S528-4 whether there is an abnormality in the lift-up motors. Instead, the process to be executed proceeds to step S28-6. The processing after step S28-6 is the same as the processing after step S11-9 in FIG. It should be noted that in step S11-10 in FIG. 7, it is determined that there is an abnormality in the lift-up mechanism, but in corresponding step S28-8 in FIG.

[Modification]
(1) In the above embodiments, the image forming apparatus is the printer 10, which is a tandem digital color printer. However, the image forming apparatus is not limited to the printer 10, and may be a tandem facsimile apparatus, an MFP (Multi Function Peripherals), or the like. Also, the printing method is not limited to the tandem method or the digital method, and may be a monochrome printer instead of a color printer.

(2) In the above-described embodiment, the signal line 104E for transmitting the lift-up motor overcurrent signal from the motor driver IC 101 to the control unit 100 and the control unit 100 are shared by the plurality of paper feed trays 60 and 70. input port 103C. However, it is not limited to this, and the plurality of paper feed trays 60 and 70 may share other configurations. It may be a line and an output port of the control unit 100 .

(3) In the above-described embodiment, what is shared by the plurality of paper feed trays 60 and 70 is the signal line 104A for output signals from the control unit 100 to the infrared LEDs 64A and 74A of the upper limit sensors 64 and 74 and the control line 104A. It is assumed that the output port 102A is the output port 102A. However, the configuration is not limited to this, and the plurality of paper feed trays 60 and 70 may share other configurations. and the input port of the control unit 100.

(4) In the above-described embodiment, the control unit 100 of the printer 10 executes the software shown in each flow chart, so that the control unit 100 realizes a plurality of predetermined functions. However, the present invention is not limited to this, and at least some of these predetermined functions may be realized by hardware circuits inside the control unit 100 .

(5) In the above embodiments, the disclosure has been made as an image forming apparatus such as the printer 10 . However, the present invention is not limited to this, and the disclosure may be regarded as a control method as shown in each of the flowcharts described above executed by an image forming apparatus such as the printer 10. The disclosure may be regarded as a control program for executing the processing shown in each flowchart.

Further, the disclosure can be regarded as a computer-readable recording medium recording the control program. This recording medium includes magnetic disks such as magnetic tapes, flexible disks and hard disks, CD-ROMs, CD-Rs, CD-RWs, DVD-ROMs, DVD-Rs, DVD-RWs, DVD-RAMs, DVD+Rs and DVD+RWs. It may be a medium such as an optical disk, a magneto-optical disk such as an MO, a memory card, or a USB memory that holds the program fixedly, or a server such as an ASP (Application Service Provider) through a communication network. It may be a medium that carries the program in a fluid manner so as to be downloaded.

(6) The techniques described in the embodiments and modifications are intended to be implemented independently or in combination as much as possible.

[effect]
(1) As shown in FIGS. 1 to 4, the printer 10 includes a plurality of paper feed trays 60 and 70 and a failure confirmation unit (control unit 100, upper limit sensors 64, 74, lift-up motors 65, 75, motor driver IC 101, signal lines 104A to 104K), and a control unit 100 for controlling a plurality of paper feed trays 60, . As shown in FIG. 4 , at least part of the failure checking section (output port 102A, signal line 104A, input port 103C, signal line 104F) is shared by the multiple paper feed trays 60 and 70 . As shown in steps S11-6 and after in FIG. 7 and step S28-2 and after in FIG. Check for faults when

As a result, at least part of the failure checking section is shared by the plurality of paper feed trays 60 and 70, so that the manufacturing cost can be prevented from increasing. Further, even when at least a part of the failure confirmation unit is shared by the plurality of paper feed trays 60 and 70, the control unit 100 operates one of the plurality of paper feed trays 60 and 70. Since the failure is confirmed when the paper feed trays 60 and 70 are on, the failure of the paper feed trays 60 and 70 can be detected. As a result, failures in the paper feed trays 60 and 70 can be reliably detected while reducing manufacturing costs.

(2) As shown in FIGS. 3 and 4, the paper feed trays 60 and 70 have a lift-up motor 65 for moving the paper S stored in the paper feed trays 60 and 70 to a position where paper can be fed; 75 included. As shown in FIG. 4, the failure confirmation unit is a drive failure confirmation unit (control unit 100, lift-up motors 65, 75, motor driver IC 101, signal lines 104D to 104K) that confirms failure of lift-up motors 65, 75. including. As shown in FIG. 4 , at least part of the drive failure checking section (input port 103C, signal line 104F) is shared by the plurality of paper feed trays 60 and 70 .

As a result, failures of the paper feed trays 60 and 70 can be reliably detected while reducing manufacturing costs.

(3) As shown in FIGS. 3 and 4, the paper feed trays 60 and 70 have an upper limit for detecting whether or not the paper S accumulated in the paper feed trays 60 and 70 has been moved to a position where paper can be fed. Includes sensors 64 , 74 . The failure confirmation unit includes a detection failure confirmation unit (control unit 100, upper limit sensors 64, 74, signal lines 104A to 104C) that confirms failure of upper limit sensors 64, 74. FIG. At least part of the detection/failure confirmation unit (output port 102A, signal line 104A) is shared by the plurality of paper feed trays 60 and 70 .

As a result, failures of the paper feed trays 60 and 70 can be reliably detected while reducing manufacturing costs.

(4) As shown in FIG. 7, the failure checking unit checks failure of the upper limit sensors 64, 74 before failure of the lift-up motors 65, 75.

As a result, since it is first confirmed that there is no abnormality in the upper limit sensors 64, 74, and then abnormality in the lift-up motors 65, 75 is confirmed, failure can be detected efficiently and reliably.

(5) As shown in step S3 in FIG. 5, the failure checking unit checks for failures at timings when the operations of the plurality of paper feed trays 60 and 70 do not overlap.

As a result, it is possible to reliably detect the failure of the paper feed tray without being affected by the confirmation of the failure of other paper feed trays.

(6) As shown in steps S3 and S5 in FIG. 5, when the failure confirmation unit confirms that the paper feed trays 60 and 70 are out of order, the control unit 100 operation is prohibited.

As a result, the operation of the paper feed trays 60 and 70 can be prevented from affecting the confirmation of failure of other paper feed trays.

(7) As shown in steps S3 and S11 of FIG. 5 and FIG. 7, the controller 100 confirms that at least two of the plurality of paper feed trays 60 and 70 are out of order. The two or more paper feed trays 60 and 70 to be checked are operated in order (specifically, after the operation during identification of the defective parts of the other paper feed trays in step S3 is completed, the relevant paper feed in step S11 An action is initiated to identify the faulty part in the tray). As shown in steps S3 and S11 in FIG. 5 and in FIG. 7, the failure confirmation unit sequentially confirms failure of the paper feed trays 60 and 70 operated by the control unit.

As a result, the operation of the paper feed trays 60 and 70 can be prevented from affecting the confirmation of failure of other paper feed trays.

(8) As shown in FIGS. 1 and 3, the control section 100 can perform control to feed the paper S from one of the paper feed trays 60 and 70 . As shown in steps S10 and S11 in FIG. 5, the failure confirmation unit prohibits failure confirmation of the paper feed trays 60 and 70 when the control unit 100 is executing the control to feed the paper S. do.

As a result, the operation of the paper feed trays 60 and 70 can be prevented from affecting the confirmation of failure of other paper feed trays. Further, since the control for feeding the paper S is not interrupted to confirm the failure of the paper feed trays 60 and 70, the downtime of printing using the paper S can be suppressed.

(9) As shown in steps S22 and S5 in FIG. 9, when the paper feed trays 60 and 70 are replenished with the paper S, the control section 100 causes the failure checking section to cause the other paper feed trays 60 and 70 to The lift-up motors 65 and 75 are controlled so as to move the paper S to a position where the paper S can be fed even when the failure of the motor is confirmed.

As a result, when the sheets S are replenished in the sheet feeding trays 60 and 70, the sheets S can be efficiently moved to a position where they can be fed.

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present disclosure is indicated by the scope of the claims rather than the above description, and is intended to include all modifications within the scope and meaning of equivalents of the scope of the claims.

10 printer, 11 discharge tray, 12 transfer belt, 14, 16 rollers, 20, 20C, 20K, 20M, 20Y imaging unit, 22 photoreceptor drum, 24 charger, 26 print head, 28 developer, 30 primary transfer roller , 30C, 30K, 30M, 30Y temporary transfer roller, 32 cleaner, 34 secondary transfer roller, 36 transfer area, 38 cleaner blade, 40 waste toner box, 46 conveyance path, 48 timing roller pair, 50 fixing unit, 60,70 Paper feed tray 61 push-up plate 61A spindle 62, 72 paper feed roller 63A, 63B regulation plate 64, 74 upper limit sensor 64A, 74A infrared LED 64B, 74B phototransistor 65, 75 lift-up motor 100 control unit 101 motor driver IC 102A, 102B, 102C output port 103A, 103B, 103C input port 104A, 104B, 104C, 104D, 104E, 104F, 104G, 104H, 104J, 104K signal line 110 image formation section, 130 operation panel section, 140 transport section, 150 paper discharge section.

Claims (10)

a plurality of paper feeders;
a failure checking unit that checks for failures in the plurality of sheet feeding devices;
A control unit that controls a plurality of the paper feeders,
at least part of the failure confirmation unit is shared by a plurality of the paper feeders;
The failure confirmation unit confirms the failure while the control unit is operating one of the plurality of paper feeders;
The paper feeding device
including a paper detection unit that detects whether or not the paper stored in the paper feed device has been moved to a position where paper can be fed;
The failure confirmation unit includes a detection failure confirmation unit that confirms failure of the paper detection unit,
The image forming apparatus , wherein at least part of the detection/failure confirmation unit is shared by a plurality of the sheet feeding devices. The paper feeding device
including a driving unit for moving the paper stored in the paper feeder to a paper feedable position;
The failure confirmation unit includes a drive failure confirmation unit that confirms a failure of the drive unit,
2. The image forming apparatus according to claim 1, wherein at least a portion of said drive failure confirmation unit is shared by a plurality of said sheet feeding devices. 3. The image forming apparatus according to claim 2 , wherein said failure confirming unit confirms failure of said paper detecting unit prior to failure of said driving unit. 2. The image forming apparatus according to claim 1, wherein the failure confirmation unit confirms the failure at a timing when operations of the plurality of paper feeders do not overlap. 2. The image forming apparatus according to claim 1, wherein said control section prohibits operation of other said sheet feeding devices when said failure confirmation section confirms that said sheet feeding device is malfunctioning. When confirming failure of at least two or more of a plurality of paper feeders, the control unit sequentially operates the two or more paper feeders whose failures are to be confirmed,
2. The image forming apparatus according to claim 1, wherein said failure confirmation unit sequentially confirms failures of said sheet feeding devices operated by said control unit. The control unit is capable of executing control to feed paper from one of the paper feeders,
2. The image forming apparatus according to claim 1, wherein said failure confirmation unit prohibits failure confirmation of said paper feed device when said control unit is executing control to feed paper. When the sheet feeding device is replenished with paper, the control unit moves the sheet to a position where it can be fed even if the failure confirmation unit confirms that another sheet feeding device is malfunctioning. 3. The image forming apparatus of claim 2, wherein the drive unit is controlled to move. A control method for an image forming apparatus comprising: a plurality of sheet feeding devices; a failure confirmation section for confirming failure of the plurality of sheet feeding devices; and a control section for controlling the plurality of sheet feeding devices,
at least part of the failure confirmation unit is shared by a plurality of the paper feeders;
The control method is
a step in which the control unit operates one of the plurality of paper feeders;
a step in which the failure confirmation unit controls to confirm a failure when the control unit is operating one of the plurality of paper feeders;
The paper feeding device
including a paper detection unit that detects whether or not the paper stored in the paper feed device has been moved to a position where paper can be fed;
The failure confirmation unit includes a detection failure confirmation unit that confirms failure of the paper detection unit,
The control method of the image forming apparatus, wherein at least part of the detection/failure confirmation unit is shared by a plurality of the sheet feeding devices . A control program executed by the controller in an image forming apparatus comprising: a plurality of sheet feeding devices; a failure confirmation section for confirming failure of the plurality of sheet feeding devices; and a control section for controlling the plurality of sheet feeding devices. and
at least part of the failure confirmation unit is shared by a plurality of the paper feeders;
The control program is
operating one of the plurality of paper feeders;
causing the control unit to perform a step of controlling to confirm a failure while operating one of the plurality of paper feeders ;
The paper feeding device
including a paper detection unit that detects whether or not the paper stored in the paper feed device has been moved to a position where paper can be fed;
The failure confirmation unit includes a detection failure confirmation unit that confirms failure of the paper detection unit,
A control program for an image forming apparatus, wherein at least part of the detection/failure confirmation unit is shared by a plurality of the sheet feeding apparatuses .

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