Abstract: An image forming apparatus includes: an image forming unit configured to form an image; a transfer circuit configured to generate a transfer voltage, and supply the transfer voltage to transfer roller for transferring the image onto a sheet; a door provided to a mounting portion onto which the image forming unit is mounted; a sensor configured to detect an open/closed state of the door; an interlock switch configured to interrupt voltage to be supplied to the transfer circuit, in a case where the sensor detects an open state in which the door is opened; and a controller configured to: determine whether a failure has occurred or not based on a detection result of the sensor and a supplying/interrupting state of the voltage of the interlock switch; and determine, in a case where determining that the failure has occurred, which of the sensor and the interlock switch is failed.

Abstract: The image forming apparatus includes the power supply board for generating a +24V power supply voltage and a driver board for driving a load for forming an image, and an engine control board for controlling an operation of a driver board. The driver board includes a fuse which receives the 24V power supply voltage supplied from the power supply board. The driver board drives the load by +24V_FU1 voltage output from the fuse. The engine control board identifies, when an abnormality occurs in an operation of the load, a board that is a cause of the abnormality according to a voltage value of the +24V_FU1 voltage and the voltage value of the power supply voltage.

Abstract: An image forming apparatus includes: an image forming unit configured to form an image; a transfer circuit configured to generate a transfer voltage, and supply the transfer voltage to transfer roller for transferring the image onto a sheet; a door provided to a mounting portion onto which the image forming unit is mounted; a sensor configured to detect an open/closed state of the door; an interlock switch configured to interrupt voltage to be supplied to the transfer circuit, in a case where the sensor detects an open state in which the door is opened; and a controller configured to: determine whether a failure has occurred or not based on a detection result of the sensor and a supplying/interrupting state of the voltage of the interlock switch; and determine, in a case where determining that the failure has occurred, which of the sensor and the interlock switch is failed.

Abstract: An image forming apparatus capable of reducing execution time of a process for shifting the image forming apparatus from a normal operation mode to a low-power consumption operation mode. A sub interrupt controller 113 is connected to units and performs notification to a sub CPU in accordance with occurrence of a return trigger in any of the units. When shifting from the normal operation mode to the low-power consumption operation mode, a main CPU transmits mode instruction information indicative of the low-power consumption operation mode to the sub CPU. The sub CPU stores one or a plurality of units associated with the low-power consumption operation mode in advance, and sets one or a plurality of units in the sub interrupt controller, based on the mode instruction information and the plurality of units stored in association with the low-power consumption operation mode.

Abstract: An image forming apparatus capable of reducing execution time of a process for shifting the image forming apparatus from a normal operation mode to a low-power consumption operation mode. A sub interrupt controller 113 is connected to units and performs notification to a sub CPU in accordance with occurrence of a return trigger in any of the units. When shifting from the normal operation mode to the low-power consumption operation mode, a main CPU transmits mode instruction information indicative of the low-power consumption operation mode to the sub CPU. The sub CPU stores one or a plurality of units associated with the low-power consumption operation mode in advance, and sets one or a plurality of units in the sub interrupt controller, based on the mode instruction information and the plurality of units stored in association with the low-power consumption operation mode.

Abstract: An image forming apparatus includes a plurality of functions for forming an image, which are implemented by a power supply, a signal output unit, a control circuit, and a load operation unit operating in cooperation with one another. The load operation unit includes a sensor for detecting an abnormality. When the sensor has detected an abnormality, the image forming apparatus identifies a failure portion being a cause of the abnormality by checking failure portions of the power supply and the signal output unit, checking a failure portion of the control circuit when there is no failure portion in the power supply and the signal output unit, and checking a failure portion of the load operation unit when there is no failure portion in the control circuit.

Abstract: An image forming apparatus includes a laser scanner unit, an engine controller, and an image controller. The laser scanner unit includes a polygon mirror configured to reflect a laser beam to scan a photosensitive drum, and a BD sensor configured to detect the laser beam reflected by the polygon mirror to output a BD signal. The engine controller generates an image formation BD signal synchronized with the BD signal. The image controller identifies a reference reflection face based on the number of times of low levels of an image formation BD signal that has been sampled for a predetermined period from a falling edge of the image formation BD signal. The image controller corrects image data based on the identified reflection face to control image formation processing.

Abstract: The image forming apparatus includes the power supply board for generating a +24V power supply voltage and a driver board for driving a load for forming an image, and an engine control board for controlling an operation of a driver board. The driver board includes a fuse which receives the 24V power supply voltage supplied from the power supply board. The driver board drives the load by +24V_FU1 voltage output from the fuse. The engine control board identifies, when an abnormality occurs in an operation of the load, a board that is a cause of the abnormality according to a voltage value of the +24V_FU1 voltage and the voltage value of the power supply voltage.

Abstract: An image forming apparatus includes a plurality of functions for forming an image, which are implemented by a power supply, a signal output unit, a control circuit, and a load operation unit operating in cooperation with one another. The load operation unit includes a sensor for detecting an abnormality. When the sensor has detected an abnormality, the image forming apparatus identifies a failure portion being a cause of the abnormality by checking failure portions of the power supply and the signal output unit, checking a failure portion of the control circuit when there is no failure portion in the power supply and the signal output unit, and checking a failure portion of the load operation unit when there is no failure portion in the control circuit.

Abstract: An image forming apparatus includes a laser scanner unit, an engine controller, and an image controller. The laser scanner unit includes a polygon mirror configured to reflect a laser beam to scan a photosensitive drum, and a BD sensor configured to detect the laser beam reflected by the polygon mirror to output a BD signal. The engine controller generates an image formation BD signal synchronized with the BD signal. The image controller identifies a reference reflection face based on the number of times of low levels of an image formation BD signal that has been sampled for a predetermined period from a falling edge of the image formation BD signal. The image controller corrects image data based on the identified reflection face to control image formation processing.

Abstract: An image forming apparatus which can control to turn on/off a light emitting element depending on a sheet state on a manual sheet tray is provided. The image forming apparatus includes the manual feed tray on which the sheet is placed. The image forming apparatus is configured to be switchable between normal power mode and power saving mode. In the normal power mode, normal power is supplied. In the power saving mode, less power is consumed as compared to the power consumed in the normal power mode. The image forming apparatus includes a manual sheet feeding sensor which detects presence/absence of the sheet on the manual feed tray. The image forming apparatus includes a sheet length sensor S and a sheet length sensor L which include the light emitting element and a light receiving element to detect approximate sheet length of sheet placed on the manual feed tray in a conveying direction.

Abstract: An image forming apparatus includes an image forming portion; a discharge portion configured to discharge a recording material on which an image is formed by the image forming portion, wherein a delivery conveyance portion having a power source circuit is mountable in a space adjacent to the image forming portion and configured to convey the recording material to a post-processing apparatus; a detection unit configured to detect a temperature; a cooling unit configured to cool the image forming portion; and a control unit configured to control, in a case where the delivery conveyance portion is mounted, rotation of the cooling unit based on the temperature detected by the detection unit in a standby state in which an image forming operation is not performed.

Abstract: A sheet feeding apparatus includes a stacking member, an optical sensor, a detected member, and a control unit. As an amount of sheets stacked on the stacking member decreases, the detected member moves from a first position in which optical sensor light is not interrupted, then once interrupts the light, and then moves to a second position in which the light is not interrupted. Information regarding an amount of sheets transmitted by the control unit, when stored information is about the detected member in the second position, is information notifying that an amount of sheets stacked on the stacking member is less than that of information regarding an amount of sheets stacked on the stacking member transmitted by the control unit when stored information is about the detected member is in the first position.

Abstract: An image forming apparatus, including: an image forming portion; a discharge portion configured to discharge a recording material on which an image is formed by the image forming portion, wherein a delivery conveyance portion having a power source circuit is mountable in a space adjacent to the image forming portion and configured to convey the recording material to a post-processing apparatus; a detection unit configured to detect a temperature; a cooling unit configured to cool the image forming portion; and a control unit configured to control, in a case where the delivery conveyance portion is mounted, rotation and stop of the cooling unit based on the temperature detected by the detection unit in a second state in which start of an operation of forming the image is waited for after a first state in which the image is formed on the recording material by the image forming portion.

Abstract: An image forming apparatus which can control to turn on/off a light emitting element depending on a sheet state on a manual sheet tray is provided. The image forming apparatus includes the manual feed tray on which the sheet is placed. The image forming apparatus is configured to be switchable between normal power mode and power saving mode. In the normal power mode, normal power is supplied. In the power saving mode, less power is consumed as compared to the power consumed in the normal power mode. The image forming apparatus includes a manual sheet feeding sensor which detects presence/absence of the sheet on the manual feed tray. The image forming apparatus includes a sheet length sensor S and a sheet length sensor L which include the light emitting element and a light receiving element to detect approximate sheet length of sheet placed on the manual feed tray in a conveying direction.

Abstract: An image forming unit forms a toner image on an image carrier, and transfers the toner image to a recording medium. A voltage generation circuit generates a high voltage used for the image forming unit. A control circuit is connected to the voltage generation circuit via a cable, and controls the high voltage generated by the voltage generation circuit. A detection unit detects a current flowing in a load of the image forming unit to which the high voltage generated by the voltage generation circuit is applied. A determination unit determines an error in accordance with a current range in which the current detected by the detection unit falls. The current range is included among a plurality of current ranges that are in one-to-one correspondence with a plurality of errors.

Abstract: An image forming apparatus including: a reading device; an operating portion; a light source; a rotary polygon mirror; a motor configured to rotate the rotary polygon mirror; and a motor control portion configured to start the motor to control the motor at a first rotation speed in response to a fact that a predetermined action is performed on one of the operating portion and the reading device in a stopped state of the rotary polygon mirror, and then to control the motor at a second rotation speed higher than the first rotation speed in response to an instruction to start image formation from the operating portion, the motor control portion being configured to control the motor at the second rotation speed, without controlling the motor at the first rotation speed, in response to a fact that the receiving portion receives image data before the motor reaches the first rotation speed.

Abstract: An image forming apparatus which can control to turn on/off a light emitting element depending on a sheet state on a manual sheet tray is provided. The image forming apparatus includes the manual feed tray on which the sheet is placed. The image forming apparatus is configured to be switchable between normal power mode and power saving mode. In the normal power mode, normal power is supplied. In the power saving mode, less power is consumed as compared to the power consumed in the normal power mode. The image forming apparatus includes a manual sheet feeding sensor which detects presence/absence of the sheet on the manual feed tray. The image forming apparatus includes a sheet length sensor S and a sheet length sensor L which include the light emitting element and a light receiving element to detect approximate sheet length of sheet placed on the manual feed tray in a conveying direction.

Abstract: An image forming unit forms a toner image on an image carrier, and transfers the toner image to a recording medium. A voltage generation circuit generates a high voltage used for the image forming unit. A control circuit is connected to the voltage generation circuit via a cable, and controls the high voltage generated by the voltage generation circuit. A detection unit detects a current flowing in a load of the image forming unit to which the high voltage generated by the voltage generation circuit is applied. A determination unit determines an error in accordance with a current range in which the current detected by the detection unit falls. The current range is included among a plurality of current ranges that are in one-to-one correspondence with a plurality of errors.

Abstract: An image forming apparatus which can control to turn on/off the light emitting element depending on a sheet state on a manual sheet tray is provided. The image forming apparatus includes the manual feed tray on which sheet is placed. The image forming apparatus is configured to be switchable between normal power mode and power saving mode. In the normal power mode, normal power is supplied. In the power saving mode, less power is consumed as compared to the power consumed in the normal power mode. The image forming apparatus includes a manual sheet feeding sensor which detects presence/absence of the sheet on the manual feed tray. The image forming apparatus includes a sheet length sensor S and a sheet length sensor L which include light emitting element and light receiving element to detect approximate sheet length of sheet placed on the manual feed tray in a conveying direction.