Image forming device

Abstract

To provide an image forming device capable of reducing the number of harnesses that electrically connect a main board and a high-voltage board.SOLUTION: An image forming device 1 includes a main body housing 10, a photosensitive drum, a charger 62 for charging the photosensitive drum, a high-voltage board 110 capable of outputting a charging voltage to the charger 62, a main board 120 capable of transmitting a control signal for causing the high-voltage board 110 to output the charging voltage, a first wireless communication unit 130 electrically connected to the high-voltage board 110 and capable of transmitting a signal output by the high-voltage board 110, and a second wireless communication unit 140 electrically connected to the main board 120 and capable of receiving the signal transmitted by the first wireless communication unit 130.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to an image forming apparatus. [Background technology]

[0002] Conventionally, an image forming device is known that includes a high-voltage board that applies high voltage to a charger, a main board that outputs control signals to the high-voltage board, and multiple harnesses that electrically connect the main board and the high-voltage board (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-24344 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if there are many harnesses electrically connecting the main board and the high-voltage board, there is a problem that it takes time and effort to replace the high-voltage board.

[0005] Therefore, it is desirable to be able to reduce the number of harnesses that electrically connect the main board and the high-voltage board. [Means for solving the problem]

[0006] The image forming apparatus includes a main body housing, a photosensitive drum, a charger, a high-voltage board, a main board, a first wireless communication unit, and a second wireless communication unit. The charger charges the photosensitive drum. The high-voltage substrate is capable of outputting a charging voltage to the charger. The main board is capable of transmitting a control signal to the high voltage board to cause it to output a charging voltage. The first wireless communication unit is electrically connected to the high-voltage board and is capable of transmitting a signal output from the high-voltage board. The second wireless communication unit is electrically connected to the main board and is capable of receiving signals transmitted by the first wireless communication unit.

[0007] Since signals from the high-voltage board can be transmitted to the main board via the first wireless communication unit and the second wireless communication unit, the harness that electrically connects the main board and the high-voltage board can be reduced.

[0008] The high-voltage board may be capable of transmitting a feedback signal according to the charging voltage to the main board via the first wireless communication unit and the second wireless communication unit. The main board can transmit a control signal to the high-voltage board in response to the feedback signal.

[0009] The high voltage board may include an output circuit, a voltage divider circuit, and an A / D converter. The output circuit is capable of outputting a charging voltage to the charger in accordance with the control signal. The voltage dividing circuit divides the charging voltage output from the output circuit. The A / D converter converts the voltage output by the voltage divider circuit from an analog value to a digital value.

[0010] The A / D converter may be capable of outputting a converted signal obtained by converting the voltage output by the voltage divider circuit from an analog value to a digital value. The high-voltage board can transmit the converted signal to the main board via the first wireless communication unit and the second wireless communication unit.

[0011] The main board may have a main CPU, and the high-voltage board may have a high-voltage board CPU. The main CPU can send a request signal to the high voltage board requesting a conversion signal. When the high-voltage board CPU receives the request signal, it transmits the converted signal to the main CPU via the first wireless communication unit and the second wireless communication unit.

[0012] The main CPU may send a request signal to the high-voltage board CPU when the image forming device is turned on, when the cover that opens and closes the opening of the main body housing is closed, when the temperature of the fixing unit of the image forming device is raised toward a predetermined target temperature, or when a print command is received.

[0013] The main CPU may execute a type determination process for determining the type of the high voltage substrate based on the received conversion signal.

[0014] The main CPU may execute the type determination process when the image forming apparatus is powered on or when a cover that opens and closes the opening of the main body housing is closed.

[0015] When the main CPU determines in the type determination process that the type of the high-voltage substrate is not a predetermined type, it may output a high-voltage substrate abnormality signal indicating an abnormality in the high-voltage substrate.

[0016] The second wireless communication unit may be capable of transmitting a signal output by the main board to the first wireless communication unit, and the first wireless communication unit may be capable of receiving a signal transmitted by the second wireless communication unit.

[0017] Since signals from the main board can be transmitted to the high-voltage board via the second wireless communication unit and the first wireless communication unit, the harness electrically connecting the main board and the high-voltage board can be further reduced.

[0018] The main board may be capable of transmitting a control signal to the high-voltage board via the second wireless communication unit and the first wireless communication unit.

[0019] The image forming apparatus may include a harness that electrically connects the main board and the high-voltage board and supplies a power supply voltage to the high-voltage board.

[0020] The high-voltage board may supply the power supply voltage supplied from the harness to the output circuit.

[0021] The high voltage board may include a DC / DC converter. The DC / DC converter is capable of converting the power supply voltage supplied from the harness into a voltage smaller in magnitude than the power supply voltage and outputting the converted voltage.

[0022] By including a DC / DC converter on the high-voltage board, the harness electrically connecting the main board and the high-voltage board can be further reduced.

[0023] The image forming apparatus may include a developing roller that supplies toner to the photosensitive drum, and the high-voltage board may be capable of outputting a developing voltage to the developing roller.

[0024] The image forming apparatus may include a transfer device that transfers a toner image formed on the photosensitive drum onto a sheet, and the high-voltage board may be capable of outputting a transfer voltage to the transfer device.

[0025] The first wireless communication unit may be located on a high-voltage substrate.

[0026] The second wireless communication unit may be located on the main board. [Effects of the Invention]

[0027] The harness that electrically connects the main board and the high-voltage board can be reduced. [Brief explanation of the drawings]

[0028] [Figure 1] FIG. 1 is a cross-sectional view showing an image forming apparatus. [Figure 2] FIG. 2 is a block diagram showing a main board, a high-voltage board, a first wireless communication unit, and a second wireless communication unit in the first embodiment. [Figure 3] 10 is a table showing threshold values ​​for board manufacturer determination, prototype stage determination, and abnormality determination. [Figure 4] 10 is a flowchart showing an example of the operation of the main board and the high-voltage board. [Figure 5] 10 is a flowchart illustrating an example of a board manufacturer determination process. [Figure 6] 10 is a flowchart illustrating an example of a prototype stage determination process. [Figure 7] 10 is a flowchart illustrating an example of a standby abnormality determination process. [Figure 8] 10 is a flowchart showing an example of the operation of the main board and the high-voltage board when a warm-up operation is performed and a print command is received. [Figure 9] 10 is a flowchart illustrating an example of an abnormality determination process during operation. [Figure 10] FIG. 10 is a block diagram showing a main board, a high-voltage board, a first wireless communication unit, and a second wireless communication unit in a second embodiment. [Figure 11] FIG. 10 is a block diagram showing a main board, a high-voltage board, a first wireless communication unit, and a second wireless communication unit in a modified example of the first embodiment. [Figure 12] FIG. 10 is a block diagram showing a main board, a high-voltage board, a first wireless communication unit, and a second wireless communication unit in a modified example of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0029] Next, a first embodiment will be described. 1, the image forming apparatus 1 is a printer capable of forming a monochrome image on a sheet S such as paper. The image forming apparatus 1 includes a main body housing 10, a cover 20, a sheet supply unit 30, an image forming unit 40, and a discharge roller 81.

[0030] The main body housing 10 has an opening 11 . The cover 20 opens and closes the opening 11 of the main body housing 10 .

[0031] The sheet supply unit 30 includes a sheet tray 31 and a sheet supply roller 32 . The sheet tray 31 accommodates the sheets S. The sheet supply roller 32 supplies the sheet S stored in the sheet tray 31 to the image forming unit 40.

[0032] The image forming section 40 includes an exposure unit 50, a process cartridge 60, and a fixing unit 70. The exposure unit 50, the process cartridge 60, and the fixing unit 70 are located inside the main body casing 10.

[0033] The exposure unit 50 includes a light source, a deflector, a lens, a mirror, etc. The exposure unit 50 emits a light beam as shown by the imaginary line to expose the surface of the photosensitive drum 61.

[0034] With the cover 20 open, the process cartridge 60 can be attached to and detached from the main body casing 10 through the opening 11. The process cartridge 60 includes a drum cartridge 60A and a developing cartridge 60B.

[0035] The drum cartridge 60A includes a photosensitive drum 61, a charger 62, and a transfer roller 63 as an example of a transfer device. A toner image is formed on the surface of the photosensitive drum 61 .

[0036] The developing cartridge 60B is detachably attached to the drum cartridge 60A and includes a developing roller 64, a supply roller 65, a layer thickness regulating blade 66, an agitator 67, and a toner containing portion 68.

[0037] The toner storage section 68 stores toner. The agitator 67 agitates the toner in the toner storage unit 68. The agitator 67 also supplies the toner to the supply roller 65. The supply roller 65 supplies the toner to the developing roller 64 . The layer thickness regulating blade 66 comes into contact with the surface of the developing roller 64 and regulates the thickness of the toner on the developing roller 64 to a constant thickness.

[0038] The fixing unit 70 includes a heating unit 71 , a pressure roller 72 , and an intermediate discharge roller 73 . The heating unit 71 includes a heater 71A, a fixing belt 71B, a nip plate, etc. The heating unit 71 heats the sheet S. The pressure roller 72 presses the sheet S against the heating unit 71 .

[0039] The charger 62 charges the surface of the photosensitive drum 61 . The exposure unit 50 emits a light beam onto the surface of the charged photosensitive drum 61, thereby forming an electrostatic latent image on the photosensitive drum 61 based on image data. The developing roller 64 supplies toner to the surface of the photosensitive drum 61 after exposure, thereby forming a toner image on the photosensitive drum 61.

[0040] The transfer roller 63 transfers the toner image formed on the photosensitive drum 61 onto the sheet S by conveying the sheet S supplied from the sheet supply unit 30 between the photosensitive drum 61 and the transfer roller 63. The fixing device 70 fixes the toner image transferred onto the sheet S by conveying the sheet S, onto which the toner image has been transferred, between the heating unit 71 and the pressure roller 72.

[0041] The intermediate discharge rollers 73 transport the sheet S on which the toner image has been fixed toward the discharge rollers 81. The discharge rollers 81 discharge the sheet S on which the image has been formed onto the discharge tray 13.

[0042] 2, the image forming apparatus 1 further includes a high-voltage board 110, a main board 120, a first wireless communication unit 130, a second wireless communication unit 140, and an alarm device 150. The high-voltage board 110, the main board 120, the first wireless communication unit 130, and the second wireless communication unit 140 are located inside the main body housing 10.

[0043] The high-voltage board 110 is a board capable of outputting a charging voltage to the charger 62. The charger 62 charges the photosensitive drum 61 by applying the charging voltage.

[0044] Furthermore, the high-voltage board 110 is capable of outputting a development voltage to the development roller 64. The development roller 64 supplies toner to the photosensitive drum 61 when the development voltage is applied thereto.

[0045] Furthermore, the high-voltage board 110 can output a transfer voltage to the transfer roller 63. The transfer roller 63 transfers the toner image formed on the photosensitive drum 61 onto the sheet S by applying the transfer voltage.

[0046] The high-voltage board 110 is electrically connected to a first grounding member 161. The first grounding member 161 is a member that serves as the ground level of the high-voltage board 110. As an example, the first grounding member 161 is a metal plate. The first grounding member 161 is located inside the main body housing 10. The high-voltage board 110 is fixed to the first grounding member 161.

[0047] The main board 120 is a board capable of transmitting a control signal for causing the high voltage board 110 to output a charging voltage.

[0048] The main board 120 is electrically connected to a second grounding member 162. The second grounding member 162 is a member that serves as the ground level of the main board 120. As an example, the second grounding member 162 is a metal plate. The second grounding member 162 is located inside the main body housing 10. The main board 120 is fixed to the second grounding member 162. In the embodiment, the second grounding member 162 is electrically connected to the first grounding member 161.

[0049] The first wireless communication unit 130 is a communication unit capable of performing wireless communication with the second wireless communication unit 140. The first wireless communication unit 130 is capable of performing short-range wireless communication with the second wireless communication unit 140. Standards for short-range wireless communication include, for example, Wi-Fi (registered trademark), BLUETOOTH (registered trademark), and ZIGBEE (registered trademark).

[0050] The first wireless communication unit 130 is electrically connected to the high-voltage substrate 110. In the embodiment, the first wireless communication unit 130 is located on the high-voltage substrate 110. The first wireless communication unit 130 can transmit a signal output by the high-voltage substrate 110 to the second wireless communication unit 140.

[0051] The second wireless communication unit 140 is electrically connected to the main board 120. In the embodiment, the second wireless communication unit 140 is located on the main board 120. The second wireless communication unit 140 is capable of receiving a signal transmitted by the first wireless communication unit 130. The second wireless communication unit 140 outputs the signal received from the first wireless communication unit 130 to the main board 120.

[0052] The high-voltage board 110 can output a feedback signal according to the output charging voltage. The high-voltage board 110 can transmit the feedback signal to the main board 120 via the first wireless communication unit 130 and the second wireless communication unit 140. The main board 120 can transmit a control signal to the high-voltage board 110 in response to the received feedback signal.

[0053] The notification device 150 is a device for notifying the user of the image forming apparatus 1 of information. The notification device 150 is, for example, a display such as a liquid crystal display, a speaker, a lamp, etc. The notification device 150 may also be configured by combining two or more displays, speakers, lamps, etc. The notification device 150 may be a display, a speaker, etc. provided in the image forming apparatus 1, or may be a display of a device separate from the image forming apparatus 1, such as a personal computer or a smartphone.

[0054] The image forming apparatus 1 further includes a first harness 171 and a second harness 172. The first harness 171 and the second harness 172 are located inside the main body housing 10. The first harness 171 and the second harness 172 electrically connect the main board 120 and the high-voltage board 110.

[0055] The first harness 171 is a harness for supplying a power supply voltage from the main board 120 to the high-voltage board 110. In the embodiment, the first harness 171 corresponds to the "harness." The power supply voltage may be, for example, a voltage supplied to the main board 120 from a low-voltage board (not shown) or a voltage obtained by converting an AC voltage supplied to the main board 120 from a commercial power source into a DC voltage.

[0056] The second harness 172 is a harness for transmitting signals output by the main board 120 to the high-voltage board 110. In the first embodiment, the main board 120 can transmit signals such as control signals to the high-voltage board 110 via the second harness 172.

[0057] The high-voltage board 110 has an output circuit 111, a voltage dividing circuit 112, a microcomputer 113, and a DC / DC converter 114. The high-voltage board 110 supplies the power supply voltage supplied from the first harness 171 to the output circuit 111 and the DC / DC converter 114.

[0058] The output circuit 111 can output a charging voltage to the charger 62. The output circuit 111 can output a developing voltage to the developing roller 64. The output circuit 111 can output a transfer voltage to the transfer roller 63. The output circuit 111 can output a high voltage according to a control signal from the main board 120.

[0059] The voltage dividing circuit 112 divides the voltage such as the charging voltage output from the output circuit 111. The voltage dividing circuit 112 can output a voltage according to the high voltage output from the output circuit 111.

[0060] The microcomputer 113 includes an A / D converter 115 and a high-voltage board CPU 116 . The A / D converter 115 converts the voltage output by the voltage dividing circuit 112 from an analog value to a digital value. The A / D converter 115 can output a converted signal obtained by converting the voltage output by the voltage dividing circuit 112 from an analog value to a digital value. The converted signal is a voltage value.

[0061] The high-voltage board 110 can transmit the converted signal to the main board 120 via the first wireless communication unit 130 and the second wireless communication unit 140. In particular, the high-voltage board CPU 116 can transmit the converted signal to the main board 120 via the first wireless communication unit 130 and the second wireless communication unit 140.

[0062] The DC / DC converter 114 is capable of converting the power supply voltage supplied from the first harness 171 into a voltage smaller than the power supply voltage and outputting the converted voltage. As an example, the DC / DC converter 114 is capable of converting the 24 V power supply voltage supplied from the first harness 171 into a 3.3 V voltage and outputting the converted voltage. The DC / DC converter 114 supplies the converted voltage to the voltage divider circuit 112, the microcomputer 113, and the first wireless communication unit 130.

[0063] The main board 120 includes a main CPU 121 . The main CPU 121 can transmit a request signal to the high-voltage board 110. The request signal is a signal that requests the converted signal output by the A / D converter 115.

[0064] The main CPU 121 transmits a request signal to the high-voltage board CPU 116 when (1) the image forming apparatus 1 is powered on, (2) the cover 20 is closed, (3) a warm-up operation is performed, or (4) a print command is received. The warm-up operation includes, for example, an operation to raise the temperature of the fixing device 70 to a predetermined target temperature, an operation to rotate the photosensitive drum 61, the developing roller 64, the agitator 67, etc., an operation to charge the surface of the photosensitive drum 61 to a predetermined potential, etc.

[0065] The main CPU 121 transmits a request signal to the high-voltage board CPU 116 via the second harness 172 .

[0066] When the high-voltage board CPU 116 receives the request signal, it transmits a conversion signal to the main CPU 121 via the first wireless communication unit 130 and the second wireless communication unit 140. When performing a warm-up operation, the conversion signal transmitted from the high-voltage board CPU 116 when a print command is received also serves as a feedback signal.

[0067] The main CPU 121 executes a type determination process when the image forming apparatus 1 is powered on or when the cover 20 is closed. The type determination process is a process for determining the type of the high-voltage board 110.

[0068] The main CPU 121 executes a type determination process based on the received conversion signal. In the embodiment, the main CPU 121 executes, as the type determination process, a substrate manufacturer determination process for determining the substrate manufacturer that manufactured the high-voltage substrate 110, and a prototype stage determination process for determining the prototype stage of the high-voltage substrate 110.

[0069] 3, in the board manufacturer determination process, if the converted signal VD is greater than the threshold value V1, the main CPU 121 determines that the board manufacturer is Company A. In the board manufacturer determination process, if the converted signal VD is equal to or less than the threshold value V1, the main CPU 121 determines that the board manufacturer is Company B.

[0070] Furthermore, in the prototype stage determination process, if the converted signal VD is equal to or greater than the threshold V21 and less than the threshold V22, the main CPU 121 determines that the prototype stage is S1 (stage 1). In the prototype stage determination process, if the converted signal VD is equal to or greater than the threshold V22 and less than the threshold V23, the main CPU 121 determines that the prototype stage is S2 (stage 2).

[0071] In the prototype stage determination process, if the converted signal VD is equal to or greater than the threshold V23 and less than the threshold V24, the main CPU 121 determines that the prototype stage is S3 (stage 3). In the prototype stage determination process, if the converted signal VD is equal to or greater than the threshold V24 and less than the threshold V25, the main CPU 121 determines that the prototype stage is S4 (stage 4).

[0072] The threshold values ​​V21 to V25 may be the same regardless of the board manufacturer, or may be different values ​​for each board manufacturer.

[0073] When the main CPU 121 determines in the type determination process that the type of the high-voltage substrate 110 is not a predetermined type, it outputs a high-voltage substrate abnormality signal indicating an abnormality in the high-voltage substrate 110. In the embodiment, the main CPU 121 outputs the high-voltage substrate abnormality signal to the alarm device 150 when the conversion signal VD is less than the threshold value V21 or when the conversion signal VD is equal to or greater than the threshold value V25 in the prototype stage determination process.

[0074] When the alarm device 150 receives the high-voltage substrate abnormality signal, it notifies the user of the abnormality in the high-voltage substrate 110. For example, the alarm device 150 displays a message to the effect that the high-voltage substrate 110 is abnormal, or emits a warning sound or voice.

[0075] The main CPU 121 executes an abnormality determination process based on the received conversion signal. The abnormality determination process is a process for determining whether or not the received conversion signal is abnormal. In the embodiment, the main CPU 121 executes the abnormality determination process after executing the type determination process. More specifically, the main CPU 121 executes the abnormality determination process after executing the board manufacturer determination process and the prototype stage determination process.

[0076] In the abnormality determination process, if the conversion signal VD is greater than the threshold value V3n (V31 to V38), the main CPU 121 outputs a voltage abnormality signal to the alarm device 150. In the embodiment, the threshold value V3n (V31 to V38) is set for each board manufacturer and each prototype stage.

[0077] When the alarm device 150 receives the voltage abnormality signal, it notifies the user of an abnormality in the voltage output from the high-voltage board 110. For example, the alarm device 150 displays a message to the effect that the converted signal from the high-voltage board 110 is abnormal, or emits a warning sound or voice.

[0078] Next, an example of the operation of the main board 120 and the high-voltage board 110 will be described with reference to a flowchart.

[0079] 4, when the image forming apparatus 1 is powered on or the cover 20 is closed, the main board 120 transmits a request signal to the high-voltage board 110 via the second harness 172 (S111). When the high-voltage board 110 receives the request signal, it reads the converted signal VD (S112). Next, the high-voltage board 110 transmits the converted signal VD to the main board 120 via the first wireless communication unit 130 and the second wireless communication unit 140 (S113).

[0080] When the main board 120 receives the converted signal VD, it executes a board manufacturer determination process (S120). More specifically, as shown in FIG. 5, the main board 120 determines whether the converted signal VD is equal to or less than a threshold value V1 (S121). If the converted signal VD is not equal to or less than the threshold value V1 (S121, No), the main board 120 determines that the board manufacturer is Company A (S122). If the converted signal VD is equal to or less than the threshold value V1 (S121, Yes), the main board 120 determines that the board manufacturer is Company B (S123).

[0081] 4, after executing the board manufacturer determination process (S120), the main board 120 transmits a request signal to the high-voltage board 110 via the second harness 172 (S131). The high-voltage board 110 reads the converted signal VD (S132). The high-voltage board 110 transmits the converted signal VD to the main board 120 via the first wireless communication unit 130 and the second wireless communication unit 140 (S133).

[0082] When the main board 120 receives the converted signal VD, it executes a prototype stage determination process (S140). Specifically, as shown in Fig. 6, the main board 120 determines whether the converted signal VD is equal to or greater than a threshold V21 and less than a threshold V22 (S141). If the converted signal VD is equal to or greater than the threshold V21 and less than the threshold V22 (S141, Yes), the main board 120 determines that the prototype stage is S1 (stage 1) (S142).

[0083] If the converted signal VD is not equal to or greater than the threshold V21 and less than the threshold V22 (S141, No), the main board 120 determines whether the converted signal VD is equal to or greater than the threshold V22 and less than the threshold V23 (S143). If the converted signal VD is equal to or greater than the threshold V22 and less than the threshold V23 (S143, Yes), the main board 120 determines that the prototype stage is S2 (stage 2) (S144).

[0084] If the converted signal VD is not equal to or greater than the threshold V22 and less than the threshold V23 (S143, No), the main board 120 determines whether the converted signal VD is equal to or greater than the threshold V23 and less than the threshold V24 (S145). If the converted signal VD is equal to or greater than the threshold V23 and less than the threshold V24 (S145, Yes), the main board 120 determines that the prototype stage is S3 (stage 3) (S146).

[0085] If the converted signal VD is not equal to or greater than the threshold V23 and less than the threshold V24 (S145, No), the main board 120 determines whether the converted signal VD is equal to or greater than the threshold V24 and less than the threshold V25 (S147). If the converted signal VD is equal to or greater than the threshold V24 and less than the threshold V25 (S147, Yes), the main board 120 determines that the prototype stage is S4 (stage 4) (S148).

[0086] If the conversion signal VD is not greater than or equal to the threshold V24 and less than the threshold V25 (S147, No), the main substrate 120 outputs a high-voltage substrate abnormality signal to the alarm device 150 (S149) and ends the processing. The alarm device 150 notifies the user of the abnormality in the high-voltage substrate 110.

[0087] 4, after determining the prototype stage in the prototype stage determination process (S140), the main board 120 transmits a request signal to the high-voltage board 110 via the second harness 172 (S151). The high-voltage board 110 reads the converted signal VD (S152). The high-voltage board 110 transmits the converted signal VD to the main board 120 via the first wireless communication unit 130 and the second wireless communication unit 140 (S153).

[0088] When the main board 120 receives the converted signal VD, it executes standby abnormality determination processing (S160). Specifically, as shown in Fig. 7, the main board 120 determines whether the converted signal VD is greater than a threshold value V3n (V31 to V38) according to the board manufacturer and the prototype stage (S161).

[0089] If the conversion signal VD is greater than the threshold value V3n (S161, Yes), the main board 120 outputs a voltage abnormality signal to the alarm device 150 (S162) and ends the process. The alarm device 150 notifies the user of the voltage abnormality. If the conversion signal VD is equal to or less than the threshold value V3n (S161, No), the main board 120 continues the process of the flowchart shown in FIG.

[0090] 4, if no abnormality is detected in the standby abnormality determination process (S160), the main board 120 executes a warm-up operation (S200). When the warm-up operation is completed, the main board 120 ends the process.

[0091] 8, when a warm-up operation is to be performed or a print command is received, main board 120 transmits a high-voltage output start signal to high-voltage board 110 via second harness 172 (S211). When high-voltage board 110 receives the high-voltage output start signal, it starts high-voltage output corresponding to the warm-up operation or the print operation (S212). Specifically, high-voltage board 110 outputs a charging voltage corresponding to the warm-up operation or the print operation to charger 62, for example.

[0092] When a predetermined time has elapsed since transmitting the high-voltage output start signal, the main board 120 transmits a request signal to the high-voltage board 110 via the second harness 172 (S221). When the high-voltage board 110 receives the request signal, it reads the conversion signal VD (S222). Next, the high-voltage board 110 transmits the conversion signal (feedback signal) VD to the main board 120 via the first wireless communication unit 130 and the second wireless communication unit 140 (S223).

[0093] When the main board 120 receives the converted signal VD, it executes an operation abnormality determination process (S240). Specifically, as shown in Fig. 9, the main board 120 determines whether the converted signal VD is greater than a threshold value V3n (V31 to V38) according to the board manufacturer and the prototype stage (S241).

[0094] If the conversion signal VD is greater than the threshold value V3n (S241, Yes), the main board 120 transmits a high voltage output stop signal to the high voltage board 110 via the second harness 172 (S242). When the high voltage board 110 receives the high voltage output stop signal, it stops the high voltage output (S243). In addition, the main board 120 outputs a voltage abnormality signal to the alarm device 150 (S244) and ends the processing. The alarm device 150 notifies the user of an abnormality in the voltage output from the high voltage board 110.

[0095] If the converted signal VD is equal to or less than the threshold value V3n (S241, No), the main board 120 continues the processing of the flowchart shown in FIG.

[0096] 8, if no abnormality is detected in the operation abnormality determination process (S240), the main board 120 determines whether the warm-up operation or printing has finished (S251). If the warm-up operation or printing has not finished (S251, No), the main board 120 calculates a control signal for high-voltage output according to the conversion signal (feedback signal) VD (S261). The main board 120 transmits the calculated control signal to the high-voltage board 110 via the second harness 172 (S262).

[0097] When the high-voltage board 110 receives the control signal, it controls the high-voltage output in accordance with the control signal (S263). Specifically, the high-voltage board 110 outputs a charging voltage in accordance with the control signal to, for example, the charger 62. The high-voltage board 110 reads the converted signal VD (S222). The high-voltage board 110 transmits the converted signal VD to the main board 120 via the first wireless communication unit 130 and the second wireless communication unit 140 (S223).

[0098] When main board 120 receives conversion signal VD, it executes an operation abnormality determination process (S240), and if no abnormality is detected, proceeds to step S251. In step S251, if the warm-up operation or printing is completed (Yes), main board 120 sends a high-voltage output stop signal to high-voltage board 110 via second harness 172 (S271). When high-voltage board 110 receives the high-voltage output stop signal, it stops high-voltage output (S272).

[0099] Next, the effects of the first embodiment will be described. Since signals from the high-voltage board 110 can be transmitted to the main board 120 via the first wireless communication unit 130 and the second wireless communication unit 140, it is possible to reduce the number of harnesses that electrically connect the main board 120 and the high-voltage board 110. This reduces the effort required when replacing the high-voltage board 110.

[0100] Furthermore, in the first embodiment, the first grounding member 161 and the second grounding member 162 are electrically connected to each other, and therefore a resistance exists between the first grounding member 161 and the second grounding member 162. When a current flows through the resistance between the first grounding member 161 and the second grounding member 162, a potential difference may occur between the ground level of the first grounding member 161 and the ground level of the second grounding member 162.

[0101] When a feedback signal from the high-voltage board 110 is transmitted to the main board 120 via a harness that electrically connects the main board 120 and the high-voltage board 110, for example, the feedback signal may be shifted by the above-mentioned potential difference. In the embodiment, the feedback signal is transmitted to the main board 120 via the first wireless communication unit 130 and the second wireless communication unit 140, thereby suppressing the effect of the above-mentioned potential difference on the feedback signal.

[0102] Furthermore, since the high-voltage board 110 has the DC / DC converter 114, there is no need to provide a harness that electrically connects the main board 120 and the high-voltage board 110 and supplies a voltage (e.g., 3.3 V) different from the power supply voltage (e.g., 24 V) supplied by the first harness 171 to the voltage divider circuit 112, the microcomputer 113, etc. This makes it possible to further reduce the number of harnesses that electrically connect the main board 120 and the high-voltage board 110.

[0103] Next, a second embodiment will be described. The following description will focus on differences from the previously described embodiment. The same components will be denoted by the same reference numerals and descriptions thereof will be omitted.

[0104] 10, in the second embodiment, the image forming apparatus 1 does not include the second harness 172 (see FIG. 2). In the second embodiment, the second wireless communication unit 140 can transmit a signal output from the main board 120 to the first wireless communication unit 130. In addition, the first wireless communication unit 130 can receive a signal transmitted by the second wireless communication unit 140.

[0105] The main board 120 can transmit signals such as control signals and request signals to the high-voltage board 110 via the second wireless communication unit 140 and the first wireless communication unit 130. In particular, the main CPU 121 can transmit signals such as control signals and request signals to the high-voltage board CPU 116 via the second wireless communication unit 140 and the first wireless communication unit 130.

[0106] In the second embodiment, in steps S111, S131, and S151 in Fig. 4 and step S221 in Fig. 8, the main board 120 transmits a request signal to the high-voltage board 110 via the second wireless communication unit 140 and the first wireless communication unit 130. In step S262 in Fig. 8, the main board 120 transmits a control signal to the high-voltage board 110 via the second wireless communication unit 140 and the first wireless communication unit 130.

[0107] In step S211 of Fig. 8, main board 120 transmits a high-voltage output start signal to high-voltage board 110 via second wireless communication unit 140 and first wireless communication unit 130. In step S271 of Fig. 8 and step S242 of Fig. 9, main board 120 transmits a high-voltage output stop signal to high-voltage board 110 via second wireless communication unit 140 and first wireless communication unit 130.

[0108] In the second embodiment, signals from the main board 120 can be transmitted to the high-voltage board 110 via the second wireless communication unit 140 and the first wireless communication unit 130, which further reduces the number of harnesses that electrically connect the main board 120 and the high-voltage board 110. Specifically, there is no need to provide the second harness 172 described in the first embodiment.

[0109] Although the embodiment has been described above, the image forming apparatus can be modified as appropriate as exemplified below.

[0110] In the above-described embodiment, the high-voltage substrate 110 has the DC / DC converter 114, but as shown in, for example, FIGS. 11 and 12, the high-voltage substrate 110 does not have to have a DC / DC converter.

[0111] 11 and 12, image forming apparatus 1 includes third harness 173 that electrically connects main board 120 and high-voltage board 110. Third harness 173 is a harness for supplying high-voltage board 110 with a second voltage (e.g., 3.3 V) that is different from the first voltage (e.g., 24 V) supplied by first harness 171. High-voltage board 110 supplies the second voltage supplied from third harness 173 to voltage divider circuit 112, microcomputer 113, and first wireless communication unit 130.

[0112] In the above-described embodiment, the microcomputer 113 has the A / D converter 115, but for example, the high-voltage board may have an A / D converter separate from the microcomputer. The high-voltage board may have an A / D converter outside the microcomputer.

[0113] In the above embodiment, the main CPU 121 executes the type determination process based on the conversion signal, but for example, the high-voltage substrate CPU may execute the type determination process based on the conversion signal.

[0114] In the above-described embodiment, the first wireless communication unit 130 is located on the high-voltage board 110, but for example, the first wireless communication unit may not be located on the high-voltage board but may be electrically connected to the high-voltage board by a harness. Similarly, in the above-described embodiment, the second wireless communication unit 140 is located on the main board 120, but for example, the second wireless communication unit may not be located on the main board but may be electrically connected to the main board by a harness.

[0115] In the above embodiment, the transfer roller 63 is exemplified as the transfer device, but the transfer device may be, for example, a transfer charger or the like.

[0116] In the above-described embodiment, the image forming apparatus 1 is a printer capable of forming only monochrome images, but the image forming apparatus may be, for example, a printer capable of forming color images, a copier, a multifunction peripheral, or the like.

[0117] The elements described in the above-described embodiment and modifications may be implemented in any combination. [Explanation of symbols]

[0118] 1. Image forming device 10 Main unit housing 61 Photosensitive drum 62 Charger 110 High-voltage board 120 Main board 130 First wireless communication unit 140 Second wireless communication unit

Claims

1. An image forming apparatus, A main body housing; A photosensitive drum; a charger that charges the photosensitive drum; a high-voltage substrate capable of outputting a charging voltage to the charger; a main board capable of transmitting a control signal for causing the high-voltage board to output the charging voltage; a first wireless communication unit electrically connected to the high-voltage board and capable of transmitting a signal output from the high-voltage board; an image forming apparatus comprising: a second wireless communication unit electrically connected to the main board, the second wireless communication unit being capable of receiving a signal transmitted by the first wireless communication unit;

2. the high-voltage board is capable of transmitting a feedback signal corresponding to the charging voltage to the main board via the first wireless communication unit and the second wireless communication unit; 2. The image forming apparatus according to claim 1, wherein the main board is capable of transmitting the control signal corresponding to the feedback signal to the high-voltage board.

3. The high-voltage substrate is an output circuit capable of outputting the charging voltage corresponding to the control signal to the charger; a voltage dividing circuit that divides the charging voltage output from the output circuit; 2. The image forming apparatus according to claim 1, further comprising an A / D converter for converting the voltage output from the voltage dividing circuit from an analog value to a digital value.

4. the A / D converter is capable of outputting a converted signal obtained by converting the voltage output by the voltage divider circuit from an analog value to a digital value; 4. The image forming apparatus according to claim 3, wherein the high-voltage board is capable of transmitting the converted signal to the main board via the first wireless communication unit and the second wireless communication unit.

5. the main board has a main CPU capable of transmitting a request signal requesting the conversion signal to the high-voltage board; 5. The image forming apparatus according to claim 4, wherein the high-voltage board has a high-voltage board CPU that, when receiving the request signal, transmits the converted signal to the main CPU via the first wireless communication unit and the second wireless communication unit.

6. The main CPU When the image forming device is turned on, When the cover for opening and closing the opening of the main body housing is closed, When the temperature of the fixing device of the image forming apparatus is increased toward a predetermined target temperature, or When a print command is received, 6. The image forming apparatus according to claim 5, wherein the request signal is transmitted to the high-voltage board CPU.

7. 6. The image forming apparatus according to claim 5, wherein the main CPU executes a type determination process for determining the type of the high-voltage board based on the received conversion signal.

8. The main CPU When the image forming device is turned on, or When the cover for opening and closing the opening of the main body housing is closed, The image forming apparatus according to claim 7 , wherein the type determination process is executed.

9. The image forming apparatus according to claim 7, wherein the main CPU outputs a high-voltage substrate abnormality signal indicating an abnormality in the high-voltage substrate when the type determination process determines that the type of the high-voltage substrate is not a predetermined type.

10. the second wireless communication unit is capable of transmitting a signal output from the main board to the first wireless communication unit; 10. The image forming apparatus according to claim 1, wherein the first wireless communication unit is capable of receiving a signal transmitted by the second wireless communication unit.

11. 11. The image forming apparatus according to claim 10, wherein the main board is capable of transmitting the control signal to the high-voltage board via the second wireless communication unit and the first wireless communication unit.

12. 4. The image forming apparatus according to claim 3, further comprising a harness electrically connecting the main board and the high-voltage board, the harness supplying a power supply voltage to the high-voltage board.

13. 13. The image forming apparatus according to claim 12, wherein the high-voltage board supplies the power supply voltage supplied from the harness to the output circuit.

14. 14. The image forming apparatus according to claim 13, wherein the high-voltage board has a DC / DC converter capable of converting the power supply voltage supplied from the harness into a voltage smaller than the power supply voltage and outputting the converted voltage.

15. a developing roller for supplying toner to the photosensitive drum; 2. The image forming apparatus according to claim 1, wherein the high-voltage board is capable of outputting a development voltage to the development roller.

16. a transfer device that transfers the toner image formed on the photosensitive drum onto a sheet; 2. The image forming apparatus according to claim 1, wherein the high-voltage board is capable of outputting a transfer voltage to the transfer device.

17. 2. The image forming apparatus according to claim 1, wherein the first wireless communication unit is located on the high-voltage board.

18. 2. The image forming apparatus according to claim 1, wherein the second wireless communication unit is located on the main board.

Images