JP2003345194A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming device for forming a stable image by preventing a carrier adhesion, jamming of transcribing material, image failure, or the like from occurring due to connection failure between a high voltage power source device and each load. <P>SOLUTION: The image forming apparatus having the high voltage power source device for supplying high voltages to an electrification means, a development means, a transcription means, and a separation means which are loads for forming image, is characterized in having a detection means for confirming the connection of each load to at least one or more outputs of the high voltage power source device. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging means, a developing means, a transfer means, which is a high-voltage contact and a load of a high-voltage power supply device,
A copying machine having a detecting means for confirming the connection with the separating means,
The present invention relates to an image forming apparatus such as a printer.

[0002]

2. Description of the Related Art In an image forming apparatus for forming an image by electrophotography, a high voltage power supply is used to charge, develop, transfer,
Image forming processing such as separation is performed. Here, the high-voltage power supply means a power supply that supplies a voltage higher than the voltage (100 V) of a general household power supply, and in such an image forming apparatus, 400 V or more, usually 1 kV to 6 kV.
It uses a high voltage power supply of the order.

In such an image forming apparatus, the charging means, developing means, transfer means, and separating means, which are loads, are connected to a high-voltage power supply device (hereinafter also referred to as a high-voltage power supply substrate) through at least one contact. Connected.

However, in the conventional image forming apparatus,
We have not checked the connection at all contacts including the charging grid.For example, if the charging grid contact or the contact of the developing bias is broken or misaligned, it is applied to the load. If the wire is disconnected before, or if the contact is forgotten to be connected during maintenance, the machine will operate but the grid voltage and development bias will not be applied, causing an abnormal phenomenon of carrier adhesion on the photoconductor. Damages the body and the developer, and sometimes even replaces the imaging system unit. Further, even when an abnormality occurs in the connection contact of the transfer unit or the separating unit other than the grid voltage and the developing bias, an image defect or a separation jam may occur.

Conventionally, in the case of abnormal connection, in a situation where abnormal discharge such as spark discharge occurs, the spark discharge detection circuit can detect and mechanical operation can be stopped, but otherwise (when no discharge occurs) it cannot be detected. There was a case where the carrier adhered.

[0006]

SUMMARY OF THE INVENTION The present invention prevents the occurrence of carrier adhesion, transfer material jamming, image defects, and the like due to poor connection between the high-voltage power supply device and each load as described above, and provides stable images. An object is to provide an image forming apparatus for forming.

[0007]

The above object can be achieved by the following constitution.

(1) In an image forming apparatus having a high voltage power supply device for supplying a high voltage to a charging means, a developing means, a transfer means and a separating means, which are loads for image formation, at least one of the high voltage power supply devices. An image forming apparatus (first invention) having a detection unit for confirming connection with each load for one or more outputs.

(2) In an image forming apparatus having a high voltage power supply device for supplying a high voltage to a charging means, a developing means, a transfer means and a separating means, which are loads for image formation, the output of the high voltage power supply device An image forming apparatus (second invention) having a detection unit for confirming connection with the charging grid and the developing bias.

(3) In an image forming apparatus having a high voltage power supply device for supplying a high voltage to a charging means, a developing means, a transfer means and a separating means, which are loads for image formation, an output contact of the high voltage power supply device. An image forming apparatus (third invention), wherein an optical sensor is used as a detection means at at least one of the connection contacts in order to confirm the connection between the load and the load.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an image forming apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

In the description of the embodiments of the present invention, the technical scope of the invention is not limited by the terms used in this specification.

FIG. 1 is a schematic diagram showing an example of the overall configuration of an image forming apparatus including a printer. In the figure, 10 is a photoconductor which is an image forming body, 11 is a charging device which is a charging unit, 12 is an exposure optical system which is an image writing unit, 13 is a developing device which is a developing unit, and 14 is the surface of the photoconductor 10. A cleaning blade for cleaning the cleaning device, 15 a cleaning blade, 16 a developing sleeve, 17 a transfer pole as a transfer means, 18 a separation pole as a means for separating the transfer material from the photoconductor 10, and 19 a photosensitive material for the transfer material. It is a separation claw for preventing wrapping around the body 10. The photoconductor 10, the charging device 11, the exposure optical system 12, the developing device 13, the transfer pole 17, the separation pole 18, the separation claw 19, the cleaning device 14, and the like constitute the image forming unit 1.

The photoconductor 10 is formed by forming a photoconductive layer such as a conductive layer, an a-Si layer or an organic photoconductive layer (OPC) on the outer periphery of a cylindrical metal base formed of, for example, an aluminum material. Is rotated in the clockwise direction as indicated by the arrow in the figure.

Reference numeral 20 is a conveyor belt having a plurality of holes, 21 is a driving roller, 22 is a driven roller, and 23 is a suction box. The surface contacting the conveyor belt 20 is provided with a plurality of holes. The transfer material P is connected to the illustrated duct, a suction fan, etc., and has a function of sucking the transfer material P onto the traveling conveyor belt 20. The conveying belt 20, the driving roller 21, the driven roller 22, the suction box 23 and the like form the conveying means 2.

Reference numeral 30 is a paper cassette, 31 is a sending roller, 32 and 33 are conveying roller pairs, 34 is a timing roller pair, 35 is a manual feeding roller, 36 is a manually feeding transfer material stacking section, 4 is a fixing device, 41 Is a heat fixing roller,
42 is a pressure bonding roller, and 70 is an image reading unit.

Next, the image forming process will be described with reference to the drawings. When a drive motor (not shown) starts rotating due to the start of image formation (recording), the photoconductor 10 rotates in the clockwise direction indicated by the arrow. At the same time, the charging device 11 starts applying a potential to the photoconductor 10.

After the electric potential is applied, on the photoconductor 10,
Image writing of an electric signal corresponding to the image data from the image reading device 70 is started through the exposure optical system 12,
An electrostatic latent image corresponding to the original image is formed on the surface of the photoconductor 10, and the electrostatic latent image is reversely developed by the developer conveyed by the developing sleeve 16 of the developing device 13 to form a toner image (visible image). Becomes

On the other hand, when the transfer material P is supplied from the paper cassette 30 stored in the machine, the transfer roller 31 is used.
Of the transfer roller 17 and the transfer roller pair 32, and is conveyed to the pair of timing rollers 34, and is sent out by the driving of the timing roller pair 34, synchronized with the toner image on the photoconductor 10, and transferred to the transfer pole 17 and the photoconductor 10. Delivered to the area between. Even in the case of manual feeding, the transfer material P on the manual feeding tray 36 is fed by the manual feeding roller 35, is conveyed to the timing roller 34 via the conveying roller pair 33, and is fed by the driving of the timing roller 34. The toner image on the photoconductor 10 is synchronized with the toner image, and the toner image is fed to the area between the transfer pole 17 and the photoconductor 10.

The toner image is transferred onto the transfer material P by the transfer pole 17 to which a voltage having a polarity opposite to that of the toner is applied.

Thereafter, the photoconductor 10 continues to rotate, is cleaned by the cleaning device 14, and is directed to the next image formation.

On the other hand, the transfer material P carrying the toner image is
The separation electrode 18 receives the charge removal action by the AC voltage, and the photoconductor 1
The attraction force with 0 is weakened, and the curvature is separated from the photoconductor 10. The transfer material P is affected by environmental humidity and the like, and
The separation claw 19 is provided for fear of being wound around 0.

The separated transfer material P is sent to the conveying means 2, is sucked by the conveying belt 20 by the suction box 23, and is conveyed to the fixing device 40. After that, the transfer material P is nipped and conveyed at the nip portion T between the heat fixing roller 41 and the pressure bonding roller 42, and heat and pressure are applied to the transfer material P, so that the toner image is melted and fixed on the transfer material P. The fixed transfer material P is discharged onto the discharge tray 71 by the fixing discharge roller 43.

Next, the present invention will be described. As described above, if the voltage from the high voltage power supply device is not applied to each of the charging, developing, transferring and separating means, the carrier adheres to the photoconductor, the image defect or the separation jam occurs.

In order to avoid the above problems, the present invention is characterized by providing a detection means for confirming the connection of the contact with each load for the output of the high voltage power supply device.

FIG. 2 is a diagram showing a connection state between the high-voltage power supply board and each load. In the figure, A is a connection contact that connects the charging wire of the charging device 11 and the output of the high-voltage power supply device (DC voltage of the same polarity as the toner). B is a charging device 11
A DC voltage having the same polarity as that of the toner is applied at the connection contact point between the grid and the output of the high-voltage power supply device in order to control the current flowing from the charging wire to the photoconductor 10. C is a connection contact between the developing sleeve 16 and the high-voltage power supply device, to which a developing bias in which a DC voltage and an AC voltage are superimposed is applied. D is a connection contact between the transfer wire of the transfer pole 17 and the high-voltage power supply device, to which a DC voltage having a polarity opposite to that of the toner is applied. E is a connection contact point between the separation wire of the separation electrode 18 and the high-voltage power supply device, to which an AC voltage superimposed with a DC voltage having the same polarity as the toner and the opposite polarity is applied. Reference numeral 50 denotes a high voltage power supply board which is a high voltage power supply device, and 100 denotes a high voltage output circuit for each load included in the high voltage power supply board 50, which supplies a predetermined voltage to each load. 101, 10
Numerals 2, 103, 104 and 105 are means for detecting the voltage or current of the charging output, grid bias, developing bias, transfer output, separation output output from the high voltage output circuit 100 and are mounted on the high voltage power supply substrate 50. ing.

The first invention is characterized in that detection means for confirming the connection of the contacts with each load is provided,
When it is confirmed that the connection with the load is not connected, the control unit 106 displays a warning message on the display unit 108 that the corresponding connection contact is not connected.

Next, the characteristics of the second invention will be described. If, in the existing circuit described above, there is a case where at least one of the connection contacts B and C is unconnected,
A corresponding detection means 102, 103 outputs a detection signal of a voltage higher than a predetermined voltage or no current, the detection signal is sent to the control unit 106, and the control unit 106
At the same time as instructing the display unit 108 to display a warning message that the corresponding connection contact is not connected,
Instruct 7 to stop machine operation.

Therefore, for example, when the charging grid is not connected, the detection means 102 displays a contact point and a warning message depending on whether the voltage is higher than a predetermined voltage or no current is applied. Then, the machine operation is stopped. If the mechanical operation continues without being stopped, the charging grid will no longer control the charging current, and unnecessary carriers will adhere to the surface of the photoconductor 10 to cause damage. The same applies to the case where the developing bias is not connected because the carrier adheres to the surface of the photoconductor 10.

FIG. 3 is a diagram showing a case where feedback is applied to the developing bias by the constant voltage circuit.

In the figure, a stable bias voltage is output from the high voltage output circuit 100 whose constant voltage is controlled and supplied to the developing sleeve 16. A detection circuit 109 is a bias voltage detection unit and is included in the control unit 106. The detection circuit 109 detects whether or not a predetermined voltage is stably output. When not connected, the bias voltage becomes 0 or an abnormal discharge waveform is detected, and the predetermined waveform is used as a reference. Detects whether the waveform is abnormal. If the high voltage output circuit 100 is under constant current control, the detection circuit 1
09 monitors the current value, and detects no current when not connected.

FIG. 4 is a flow chart when an existing circuit or a feedback circuit is used.

In the figure, after START of image recording, the corresponding high voltage output control signal is O in step S1.
N, the presence or absence of connection is detected in step S2. If the connection is YES in step S2 (within the predetermined voltage range),
Image formation is continued by the normal mechanical operation of step S4. If the connection is NO (overvoltage that is equal to or higher than the predetermined voltage) in step S2, the machine operation is stopped in step S3, and in step S5, a warning message indicating that the relevant part is not connected is displayed on the display unit. As a result, it is possible to avoid damage to the photoconductor and the developer due to unnecessary carrier adhesion.
Also, jams, abnormal images, abnormal discharge, etc. can be detected in advance.

The third invention is a method of physically detecting and confirming the connection between the load side and the high voltage power source side by using an optical sensor.

FIG. 5 is a diagram for explaining a method of detecting the connecting portion between the output contact and each load by an optical sensor.

In the figure, the alternate long and short dash line m side indicates the load side, and the alternate long and short dash line n side indicates the output side from the high voltage power supply device.

Reference numeral 201 denotes an electrode which is a connection contact on the load side,
Reference numeral 202 is a contactor which is a connection contact on the high voltage power source side.
An optical sensor 203 has a light emitting portion and a light receiving portion. The contactor 202 is a frame body 2 of the machine body via an insulating member 206.
However, it may be pulled out from the frame 205 together with the cable 207 for cleaning or the like during maintenance. The load part m slides in the direction of the arrow along a guide (not shown) to come into contact with and release from the contact 202.

If the contactor 202 is broken or misaligned, or if there is an abnormality such that the contactor 202 is forgotten to be attached to the frame 205 during maintenance, the optical sensor detects and makes a determination. The abnormality is confirmed by the section, and the abnormality signal is transmitted to the control section.

FIG. 6 is a flow chart when the optical sensor is used as the detecting means. In the figure, after START of image recording, the corresponding optical sensor 203 (see FIG. 5) is turned on in step S11, and the presence or absence of connection is detected in step S12. Contact 202 in step S12
If YES (see FIG. 5) is the normal connection position,
The process proceeds to step S14, and image formation is continued with normal mechanical operation. When the connection is NO in step S12 (when the contact 202 is not in the regular connection position), step S1
3, the machine operation is stopped, and in step S15, a warning message indicating that the relevant part is not connected is displayed on the display unit.

[0040]

EFFECT OF THE INVENTION By detecting the non-connection of the contacts before the operation of the image forming process by the high voltage power source and displaying the warning message on the display section after the machine is stopped, the photosensitive member and the developer can be unnecessarily attached to the carrier. You can avoid damage. Also,
Jam, abnormal images, abnormal discharge, etc. can be detected in advance.

[Brief description of drawings]

FIG. 1 is a schematic diagram illustrating an example of the overall configuration of an image forming apparatus including a printer.

FIG. 2 is a diagram showing a connection state between a high-voltage power supply board and each load.

FIG. 3 is a diagram showing a case where feedback is applied to a developing bias by a constant voltage circuit.

FIG. 4 is a flowchart when an existing circuit or a feedback circuit is used.

FIG. 5 is a diagram for explaining a method of detecting a connecting portion between an output contact and each load by an optical sensor.

FIG. 6 is a flowchart when an optical sensor is used as a detection means.

[Explanation of symbols]

10 photoconductor 11 Charging device 16 Development sleeve 17 Transfer pole 18 Separation pole 100 high voltage output circuit 101, 102, 103, 104, 105 Detection means

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 15/06 101 G03G 15/06 101 (72) Inventor Yoshifumi Sasamoto 2970 Ishikawacho, Hachioji, Tokyo Konica Stock Company (72) Inventor Yoshiteru Katayama 2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica Stock Company F-term (reference) 2H027 DA03 DA27 DE02 DE04 DE05 DE07 EA03 EC06 ED03 ED09 ED24 EF06 EH06 EK03 GA30 GB07 GB09 HA02 HA10 HA12 HA17 HB13 HB16 ZA05 2H073 AA01 AA05 BA04 BA13 BA27 BA41 BA45 2H200 FA11 GA16 GA18 GA23 GA34 GA57 GA59 GA60 HA12 HA29 HA30 HB03 HB28 HB48 JA02 JA28 JA29 JA30 KA07 KA28 KA29 KA30 NA02 NA06 NA09 PA27 PA29 PA30 PB02 PB02 P30

Claims (8)

[Claims] 1. A charging unit which is a load for image formation,
In an image forming apparatus having a high-voltage power supply device that supplies a high voltage to a developing device, a transfer device, and a separating device, detection for confirming connection with each load for at least one output of the high-voltage power device An image forming apparatus comprising means. 2. When the detection unit determines that the load is not connected, a message is displayed on the display unit so as to confirm the connection of the load corresponding to the disconnection. Image forming apparatus. 3. A charging unit which is a load for image formation,
An image forming apparatus having a high-voltage power supply device for supplying a high voltage to a developing device, a transfer device, and a separating device, and having a detection device for confirming the connection between the output of the high-voltage power device and the charging grid and the developing bias. An image forming apparatus characterized by. 4. When the detection means determines that no connection is made, all mechanical operations are stopped, and a message is displayed on the display unit to confirm the connection of the charging grid or the developing bias. The image forming apparatus according to claim 3, wherein the image forming apparatus is characterized in that: 5. When the high-voltage power supply device is a constant current type, the output of the high-voltage power supply device and the load are not connected because the applied voltage of the output stage is higher than a predetermined voltage. The image forming apparatus according to claim 3, further comprising a detection unit that confirms that 6. When the high-voltage power supply device is a constant voltage type, it is confirmed that the output of the high-voltage power supply device and the load are not connected because the current in the output stage is a predetermined current or more. The image forming apparatus according to claim 3, wherein the image forming apparatus comprises: 7. When the high-voltage output circuit of the high-voltage power supply device has a feedback circuit through a load, the feedback current at the time of high-voltage output is equal to or higher than a predetermined current. 5. It is confirmed that the output and the load are not connected to each other.
The image forming apparatus according to item 1. 8. A charging unit which is a load for image formation,
In an image forming apparatus having a high-voltage power supply device that supplies a high voltage to a developing device, a transfer device, and a separating device, at least one or more connection contacts for confirming connection between an output contact of the high-voltage power supply device and a load. An image forming apparatus characterized in that an optical sensor is used as a detecting means.