High-voltage circuit and image forming device
By introducing a voltage protection module into the high-voltage circuit of the image forming device, the problem of the high-voltage circuit being disturbed by external voltage is solved, and the reliability and image quality of the circuit are improved.
Patent Information
- Application Number
- CN202421661707.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-12
- Publication Date
- 2025-05-23
- Estimated Expiration
- 2034-07-12
Smart Images
Figure CN222896355U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of image forming, in particular to a high voltage circuit and an image forming device. Background Art
[0002] A color laser printer is a type of image forming device (including but not limited to printers, copiers, fax machines, scanners, and multifunction machines that integrate printing, copying, faxing, scanning, etc., whose function is to print images or text on imaging media). It adopts a secondary transfer imaging mode, that is, the charger of the laser printer will first charge the surface of the image carrier, and then transfer the toner of the developing component to the image carrier to form an image. After that, the toner is transferred to the intermediate transfer body through the potential difference between the primary transfer component of the intermediate transfer body and the surface of the image carrier, completing the first transfer in the imaging step. However, during the first transfer process, the surface of the image carrier is in contact with the intermediate transfer body and the primary transfer component, resulting in the voltage on the surface of the image carrier being transmitted to the primary transfer component through the intermediate transfer body, and the output end of the primary transfer high-voltage circuit is connected to the primary transfer component, so that the output end of the primary transfer high-voltage circuit carries the voltage, which leads to a failure of the primary transfer high-voltage circuit, affecting its normal startup and causing the printed image to be lighter or even white spots on the image. Utility Model Content
[0003] In view of the deficiencies in the prior art, the utility model provides a high-voltage circuit and an image forming device, which are used to solve the problem that the high-voltage circuit is disturbed by external voltage and its normal operation is affected.
[0004] According to a first aspect of the present utility model, a high voltage circuit is provided, which is applied to an image forming device, comprising:
[0005] Control module;
[0006] A high-voltage driving module, the input end of which is connected to the output end of the control module, and is used to control the output of the driving voltage according to the control signal;
[0007] A high-voltage conversion module, the input end of which is connected to the output end of the high-voltage driving module, and is used to convert the output voltage of the high-voltage driving module into an alternating high-voltage sine wave and output it;
[0008] A voltage doubling module, the input end of which is connected to the output end of the high-voltage conversion module, and is used to convert the alternating high-voltage sine wave output by the high-voltage conversion module into a voltage of a predetermined volt value;
[0009] A voltage protection module, the input end of the voltage protection module is connected to the output end of the voltage doubling module, the output end of the voltage protection module is used to connect an external component, and the voltage protection module is used to prevent the voltage received by the external component from flowing back into the high-voltage circuit.
[0010] A possible implementation includes:
[0011] The voltage protection module is a voltage stabilizing module, the input end of the voltage stabilizing module serves as the input end of the voltage protection module, and the output end of the voltage stabilizing module serves as the output end of the voltage protection module.
[0012] A possible implementation includes:
[0013] The voltage stabilizing module comprises a voltage stabilizing diode, a first end of the voltage stabilizing diode serves as an input end of the voltage stabilizing module, and a second end of the voltage stabilizing diode serves as an output end of the voltage stabilizing module.
[0014] A possible implementation includes:
[0015] The cathode end of the voltage stabilizing diode is connected to the output end of the voltage doubling module as the input end of the voltage stabilizing module, and the anode end of the voltage stabilizing diode is connected to the external component as the output end of the voltage stabilizing module.
[0016] A possible implementation includes:
[0017] The anode terminal of the voltage stabilizing diode is connected to the output terminal of the voltage doubling module as the input terminal of the voltage stabilizing module, and the cathode terminal of the voltage stabilizing diode is connected to the external component as the output terminal of the voltage stabilizing module.
[0018] A possible implementation includes:
[0019] The external component is a primary transfer component, a charger, a developing component, or a fixing assembly of the image forming apparatus.
[0020] A possible implementation includes:
[0021] A feedback module, wherein the input end of the feedback module is connected to the output end of the voltage doubling module, and the output end of the feedback module is connected to the feedback end of the high-voltage driving module, and is used to feed back the voltage output by the voltage doubling module to the high-voltage driving module.
[0022] A possible implementation includes:
[0023] A feedback module, wherein the input end of the feedback module is connected to the output end of the voltage protection module, and the output end of the feedback module is connected to the feedback end of the high-voltage driving module, and is used to feed back the voltage output by the voltage protection module to the high-voltage driving module.
[0024] A possible implementation method includes:
[0025] The high-voltage driving module includes an operational amplifier driving unit, a first input end of the operational amplifier driving unit serves as an input end of the high-voltage driving module, and a second input end of the operational amplifier driving unit serves as a feedback end of the high-voltage driving module.
[0026] According to a second aspect of the present invention, there is provided an image forming device, comprising:
[0027] An image carrier for carrying a toner image;
[0028] A primary transfer member, used for transferring the toner image on the image carrier to an intermediate transfer body;
[0029] an intermediate transfer body for carrying the toner image transferred from the image bearing body at the primary transfer position;
[0030] The primary transfer component is powered by the high-voltage circuit described in any embodiment of the first aspect of claim 1, and a voltage protection module of the high-voltage circuit is used to prevent the voltage of the intermediate transfer body from flowing back through the primary transfer component.
[0031] Compared with the prior art, the high-voltage circuit and image forming device provided by the utility model, the high-voltage circuit includes a control module, a high-voltage driving module, a high-voltage conversion module, a voltage doubling module and a voltage protection module. While providing high voltage to external components through the control module, the high-voltage driving module, the high-voltage conversion module and the voltage doubling module, the voltage protection module is connected to the high-voltage output end, so as to prevent the voltage received by the external components from flowing into the original voltage output of the high-voltage circuit through some means, thereby preventing the damage to the components of the high-voltage circuit and affecting its normal operation. The various embodiments of the present application help to improve the reliability of the high-voltage circuit, and are particularly suitable for image forming devices, which is beneficial to ensuring the image quality and improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Figure 1 A schematic diagram of the structure of an image forming device provided by an embodiment of the utility model;
[0033] Figure 2 A schematic diagram of a high voltage circuit structure provided for an embodiment of the utility model;
[0034] Figure 3A high voltage circuit diagram provided for an embodiment of the utility model;
[0035] Figure 4 A schematic diagram of a high voltage circuit structure provided for an embodiment of the utility model;
[0036] Figure 5 A high voltage circuit diagram provided for an embodiment of the utility model;
[0037] Figure 6 A high voltage circuit diagram provided for an embodiment of the utility model;
[0038] Figure 7 A high voltage circuit diagram provided for an embodiment of the utility model. DETAILED DESCRIPTION
[0039] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.
[0040] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.
[0041] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.
[0042] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.
[0043] Figure 1 Schematic diagram of the structure of an image forming device provided in an embodiment of the present application. Figure 1 As shown in , the image forming apparatus includes: an image carrier 101, a primary transfer component 102, a secondary transfer component 103, a first cleaning component 104, a second cleaning component 105, a control module 106, an intermediate transfer body 107, a laser scanning unit 108, a paper box 109 and a fixing assembly 110.
[0044] Image carriers 101, each image carrier is used to carry an electrostatic latent image, and the electrostatic latent image is developed by a single color toner to form a toner image. In an image forming device, both OPC and transfer belt can be used to carry a toner image. The image carrier 101 in the embodiment of the present invention specifically refers to an OPC of four colors (cyan, magenta, yellow and black) of CMYK. Among them, the first image carrier 101K is a black OPC.
[0045] The primary transfer member 102 is used to transfer the toner image on the image carrier 101 to the intermediate transfer member 107. In the present invention, the primary transfer member 102 specifically refers to a primary transfer roller. The number of primary transfer members in different image forming devices may be different. Figure 1 The number of primary transfer members 102 in the image forming apparatus shown is 4. Among them, the first primary transfer member 102K is a primary transfer member corresponding to the black OPC.
[0046] The secondary transfer member 103 is used to transfer the toner image on the intermediate transfer body 107 to the transfer material. The transfer material refers to a transfer material such as paper. The secondary transfer member 103 in the embodiment of the present invention specifically refers to a secondary transfer roller. Its function is to press the paper with the toner or the carbon ribbon during the imaging process, so that the text and the image are more vivid, and at the same time, it can prevent the deviation or misalignment during the imaging process.
[0047] The first cleaning member 104 is used to clean the residual toner on the intermediate transfer body 107. In the embodiment of the present invention, the first cleaning member 04 can be specifically implemented in the form of a cleaning scraper, which contacts the intermediate transfer body 107 to scrape off the residual toner on the intermediate transfer body 107.
[0048] The second cleaning member 105 is used to clean the residual carbon powder on the image carrier 101. In the embodiment of the present invention, the second cleaning member can be specifically implemented in the form of a cleaning scraper. Since there are four image carriers 101, four corresponding second cleaning members 105 can be configured to clean the image carriers 101 of four colors.
[0049] The control module 106 is used to control the image forming device to complete the imaging action. Alternatively, the control module 106 can also control the first driving component 115 to drive the primary transfer component 102 to drive the intermediate transfer body 107 to abut and / or separate from the image carrier 101 according to the received imaging instruction. Among them, the control module 106 can be specifically implemented in the form of a central processing unit of the image forming device. Alternatively, it can be implemented in the form of a processing unit that is independent of the central processing unit of the image forming device.
[0050] The intermediate transfer body 107 is used to carry the toner image transferred from the image carrier 101. The intermediate transfer body 107 in the embodiment of the present invention can be implemented in the form of an intermediate transfer belt. When color correction is required, a correction image needs to be formed on the intermediate transfer belt. The correction image is generally only formed on the transfer belt for color correction and will not be printed.
[0051] The laser scanning unit 108 is used to expose the image carrier 101 which has been uniformly charged to form an electrostatic latent image.
[0052] The paper box 109 is used to store transfer materials such as paper.
[0053] The fixing assembly 110 is used to print the toner image transferred onto the transfer material onto the transfer material. The fixing assembly 110 heats the paper to melt the toner transferred onto the paper and allow the toner to penetrate into the paper fibers, thereby completing the imaging process on the paper.
[0054] The charger 112 is used to charge the surface of the image carrier 101. The charger 112 can be a charging roller or a corona component close to the OPC.
[0055] The developing charging component 113 is used to apply a developing voltage to the developing component 114 .
[0056] The developing unit 114 is used for developing and forming corresponding toner images on the surface of at least one image carrier 101 .
[0057] The first driving component 115 is used to drive the primary transfer component 102 to move, and drive the intermediate transfer body 107 to switch between the state of contact with and separation from the image carrier 101. The first driving component 115 can be a pressurizing motor driving the ITU (intermediate transfer unit).
[0058] The de-static component 116 can de-staticize the paper by applying a de-static bias voltage to prevent the paper from being attached to the image carrier 101 due to static electricity on the toner band. The de-static component 116 can be a de-static needle.
[0059] like Figure 1In the image forming apparatus shown in , during the imaging process, the laser scanning unit 108 exposes the charged image carrier 101, thereby forming an electrostatic latent image on the image carrier 101. The developing unit (not shown) is generally provided with developing components 114 (such as developing rollers) corresponding to four colors. The four developing rollers are used to develop and form corresponding toner images on the OPC surface of four colors (cyan, magenta, yellow and black). Afterwards, the image forming apparatus controls the primary transfer component to abut against the photosensitive drum, so that the intermediate transfer body 107 contacts the image carrier 101, and drives the image carrier 101 and the intermediate transfer body 107 to rotate, thereby completely transferring the toner image on the image carrier 101 to the intermediate transfer body 107. As the intermediate transfer body 107 rotates, the toner image on the intermediate transfer body 107 contacts the transfer material transported from the paper box 109, and the toner image is completely transferred from the intermediate transfer body 107 to the transfer material under the action of the secondary transfer component 103. Therefore, when the image forming device stops due to abnormality during the imaging process, it is necessary to clean the residual toner on the intermediate transfer body 107 and the image carrier 101 after recovery to avoid affecting the subsequent printing effect.
[0060] The powder cartridge 111 is located above the intermediate transfer body 107. It is understandable that a color image forming apparatus is generally provided with toners of four colors (cyan, magenta, yellow and black). The stored toners are supplied to a developing unit (not shown) of an OPC including four colors (cyan, magenta, yellow and black) for imaging through a toner replenishing mechanism (not shown).
[0061] It is understood that the developing unit generally forms an image using a two-component toner including a toner and a carrier.
[0062] The control module 106 controls the first cleaning member 104 to clean the residual toner on the intermediate transfer body 107. Specifically, the first cleaning member 104 contacts the intermediate transfer body 107, and the control module 106 controls the intermediate transfer body 107 to rotate to clean the residual toner on the intermediate transfer body 107.
[0063] For the residual toner on the image carrier 101, the control module 106 needs to first confirm whether the state of each primary transfer component 102 is in the contact state. If so, the control module 107 needs to first control each primary transfer component 102 to separate from each image carrier 101, and then control each second cleaning component 105 to clean the residual toner on each image carrier 101. The primary transfer component 102 can be switched from the contact state to the standby state, which means that the primary transfer component 102 is completely separated from the four OPCs (image carrier 101), and the four OPCs do not need to rotate with the primary transfer component 102, which is convenient for toner cleaning, reduces the rotation of the OPCs, and prevents the residual toner on the intermediate transfer body 107 from being stained on the image carrier 101.
[0064] When the image forming device is set to color mode, the first driving component 115 can drive the CMYK four-color primary transfer component 102. In the standby state, the primary transfer component 102 is in a separated state, at which time the primary transfer component 102 is completely separated from the image carrier 101; when the control module 106 issues an instruction to start the imaging work, it is necessary to switch the separated state to the contact state. The control module 106 issues an instruction, the image carrier 101 starts to rotate, and the charger 112 starts to charge the image carrier 101, applying a uniform charge on the surface of the image carrier 101; when the image carrier 101 is fully charged, the developing and charging component 113 applies voltage to the developing component 114, and at the same time controls the first driving component 115 to turn on, driving the primary transfer component 102 to drive the intermediate transfer body 107 to abut against one side of the image carrier 101; after the first driving component 115 is turned on, the primary transfer component 102 moves to the first predetermined position, and the intermediate transfer body 107 is pressed by the primary transfer component 102 and the image carrier 101 is clamped, at which time the first driving component is controlled to be closed, and the intermediate transfer unit enters a contact state; due to the potential difference between the primary transfer component 102 and the surface of the image carrier 101, the colorant on the image carrier 101 is transferred to the intermediate transfer body 107; and after the colorant image on the intermediate transfer body is transferred to the transfer material, the neutralizing component 116 is turned on, and a neutralizing bias is applied to neutralize the transfer material; when the transfer work is completed, the neutralizing component 116 is turned off, and at the same time the first driving component 115 is controlled to be turned on, driving the primary transfer component 102 to drive the intermediate transfer body 107 to separate from the image carrier 101 and move to the side away from the image carrier 101; after the first driving component 115 is turned on, the primary transfer component 102 moves to the second predetermined position, and the intermediate transfer body 107 is driven by the primary transfer component 102 to separate from the image carrier 101, and at the same time the first driving component 115 is controlled to be closed, and the primary transfer component 102 returns to the standby state. During this process, the surface of the image carrier is in contact with the intermediate transfer body and the primary transfer component, causing the negative high voltage on the surface of the image carrier to be transmitted to the primary transfer component 102 through the intermediate transfer body, and the output end of the primary transfer high voltage circuit is connected to the primary transfer component 102, so that the output end of the primary transfer high voltage circuit carries the negative high voltage on the surface of the image carrier. The primary transfer high voltage circuit is in an overloaded state and cannot be started normally to complete the imaging work.
[0065] To solve the above problems, the present application embodiment proposes a high voltage circuit structure schematic diagram, such as Figure 2As shown, the high-voltage circuit 20 includes a high-voltage driving module 210, a high-voltage conversion module 220, a voltage doubling module 230, a voltage protection module 240 and a control module 106. Specifically, the input end of the high-voltage driving module 210 is connected to the output end of the control module 106, and is used to output the driving voltage according to the control signal output by the control module 106; the input end of the high-voltage conversion module 220 is connected to the output end of the high-voltage driving module 210, and is used to convert the output voltage of the high-voltage driving module 210 into an alternating high-voltage sine wave and output it; the input end of the voltage doubling module 230 is connected to the output end of the high-voltage conversion module 220, and is used to convert the alternating high-voltage sine wave output by the high-voltage conversion module 220 into a voltage of a predetermined volt value and output it; the input end of the voltage protection module 240 is connected to the output end of the voltage doubling module 230, and the output end of the voltage protection module 240 is used to connect external components to prevent the voltage received by the external components from being backflowed into the high-voltage circuit 20, so that the high-voltage circuit 20 is in an overload state and cannot be started normally. The external components may be the primary transfer component 102, the charger 112, the developer component 114 and the fixing assembly 110. The high voltage circuit 20 further includes a feedback module 250, which is connected to the output end of the voltage multiplier module 230 and is used to feed back the stable high voltage output by the voltage multiplier module 230 to the high voltage driving module 210.
[0066] Voltage backflow refers to the situation in a circuit where, when there is an external input voltage, the external input voltage flows into the output end of the voltage output circuit through some means, and the voltage output by the voltage output circuit is lower than the external input voltage, resulting in a malfunction or damage to the device or circuit. Specifically, the first transfer process of the image forming device is used as an example: the image forming device needs to apply a negative high voltage to the surface of the image carrier 101 to form an electrostatic latent image. At the first transfer position, since the surface of the image carrier 101 is in contact with the intermediate transfer body 107 and the first transfer component 102, and the output end of the first transfer high voltage circuit is connected to the first transfer component 102, at this time, since the first transfer high voltage circuit is not working, there is a negative high voltage on the surface of the image carrier 101 backflowing into the output end of the first transfer high voltage circuit, causing the first transfer high voltage circuit to malfunction. In this regard, the embodiment of the present application solves the problem of voltage backflow by setting a voltage protection module. The voltage protection module can be a circuit with a voltage interception function, such as a voltage zener diode, or a voltage limiter, or an optocoupler isolator, or a filter circuit. Here, a voltage zener diode is used for detailed description.
[0067] The high-voltage circuit proposed in the present application provides high voltage to external components through a control module, a high-voltage driving module, a high-voltage conversion module and a voltage doubling module, and at the same time, is connected to a voltage protection module at the high-voltage output end, thereby preventing the voltage received by the external components from flowing into the original voltage output of the high-voltage circuit through some means, thereby preventing the voltage from being received by the external components from flowing into the original voltage output of the high-voltage circuit, thereby causing damage to the components of the high-voltage circuit and affecting their normal operation, thereby helping to improve the reliability of the high-voltage circuit, and is particularly suitable for image forming equipment, which is beneficial to ensuring image quality and improving user experience.
[0068] Figure 3Schematic diagram of a single transfer high voltage circuit of an embodiment of the present application, the high voltage driving module 210 includes an operational amplifier driving unit, the operational amplifier driving unit may be an operational amplifier, specifically, the high voltage driving module 210 includes an operational amplifier U1B, a capacitor C8, a capacitor C9, a resistor R7 and a resistor R8, wherein 1THV PWM is a control signal transmitted from the control module 106 to the high voltage driving module 210, and the control signal 1THV PWM is filtered by an RC filter circuit composed of R8 and C9, and a stable DC voltage is output and transmitted to the non-inverting input terminal of the operational amplifier U1B as the first input source of the operational amplifier U1B. The operational amplifier U1B adjusts the voltage output according to the input voltage of the non-inverting input terminal; the feedback module 250 includes a feedback resistor R2, the input terminal of the feedback resistor R2 is connected to the output terminal of the voltage doubling module 230, and the output terminal of the feedback resistor R2 is connected to the input terminal of the high-voltage driving module 210. The stable high voltage output by the voltage doubling module 230 is fed back to the reverse input terminal of the operational amplifier U1B through the feedback resistor R2 as the second input source of the operational amplifier U1B; the high-voltage conversion module 220 includes a transformer T1, resistors R4, R5, R6, capacitor C2 and transistor Q1, the output voltage of operational amplifier U1B drives transistor Q1 to conduct, so that the voltage across 1-5 on the primary winding side of transformer T1 changes. Due to the electromagnetic induction of the transformer, an AC high-voltage sine wave is generated across the secondary winding 10-6 of transformer T1. The feedback winding 2-4 of transformer T1 synchronously generates a feedback sine wave according to the secondary winding situation and inputs it to the base of transistor Q1, thereby forming a closed-loop negative feedback and starting oscillation; the voltage doubling module 230 includes capacitors C1, C3 and diodes D2, D3. The AC high voltage generated on the secondary side of transformer T1 is rectified by the voltage doubling module 230 to generate a stable positive high voltage across capacitor C3, so that a positive high voltage is output in a single transfer process;The voltage protection module 240 includes a voltage zener diode ZD1, the cathode end of the voltage zener diode ZD1 is connected to the voltage doubling module 230, specifically, connected to the capacitor C3 of the voltage doubling module 230, and the anode end is connected to the primary transfer high voltage output terminal 1THV. Due to the characteristics of the voltage zener diode itself, even if the primary transfer high voltage output terminal 1THV is backflowed with high voltage, the voltage zener diode ZD1 is not reversely broken down. At this time, the voltage zener diode ZD1 connected to the filter capacitor C3 and the feedback resistor R2 can be regarded as a resistor with a large resistance value, thereby preventing the primary transfer high voltage output terminal 1THV from being backflowed with negative high voltage before it is turned on. The primary transfer high voltage output terminal 1THV is overloaded and is equivalent to a short circuit to the ground, which becomes The secondary side of the transformer T1 is pulled down, and the sinusoidal high voltage cannot be output normally, resulting in no output of the feedback winding 2-4, and the base voltage of the transistor Q1 cannot be changed, which eventually causes the high-voltage conversion circuit 12 to be unable to oscillate, and the primary transfer high-voltage output terminal 1THV has no high-voltage output. The primary transfer high-voltage output terminal 1THV always maintains the negative voltage value of the reverse injection, and because the feedback resistor R2 is connected to the primary transfer high-voltage output terminal 1THV through the voltage stabilizing diode ZD1, when the primary transfer high-voltage circuit is turned on, the control module 106 can obtain the voltage value at the connection between the filter capacitor C3 and the feedback resistor R2, and thus accurately adjust the size of the control signal 1THV PWM according to the voltage value and the voltage stabilizing value of the voltage stabilizing diode ZD1, thereby indirectly adjusting the output voltage of the primary transfer high-voltage output terminal 1THV, ensuring that when the primary transfer high-voltage circuit is working, the stable high voltage generated by the voltage doubling module 230 can flow through the voltage stabilizing diode ZD1 and be transmitted to the primary transfer component 102. ;
[0069] Through this embodiment, while high voltage is provided to external components through the control module, the high-voltage drive module, the high-voltage conversion module and the voltage doubling module, a voltage protection module is connected to the high-voltage output end, thereby preventing the voltage received by the external components from flowing into the original voltage output of the high-voltage circuit through some means, causing damage to the components of the high-voltage circuit and affecting its normal operation. This helps to improve the reliability of the high-voltage circuit, is particularly suitable for image forming equipment, is beneficial to ensuring image quality, improving user experience, ensuring the quality of printed images, and helping to improve user experience.
[0070] Since the voltage stabilization accuracy of the voltage stabilization value of the voltage stabilization diode ZD1 may have errors, it is impossible to achieve accurate regulation of the voltage value of the primary transfer high-voltage output terminal 1THV. Therefore, another embodiment of the present application proposes a high-voltage circuit structure schematic diagram, such as Figure 4 The input end of the feedback module 250 is connected to the output end of the voltage protection module 240, and the output end of the feedback module 250 is connected to the input end of the high-voltage driving module 210, so that the output end voltage of the voltage protection module 240 is transmitted to the input end of the high-voltage driving module 210. Specifically, Figure 5As shown, the cathode terminal of the voltage zener diode ZD1 is connected to the filter capacitor C3, and the anode terminal is connected to the feedback resistor R2 and the first transfer high-voltage output terminal 1THV. By directly transmitting the voltage value of the first transfer high-voltage output terminal 1THV to the reverse input terminal of the operational amplifier U1B of the medium and high voltage driving module 210, as the second input source of the operational amplifier U1B, and when the first transfer high-voltage circuit is turned on, the control module 106 can accurately control the size of the control signal 1THV PWM through the voltage value at the connection between the first transfer high-voltage output terminal 1THV and the feedback resistor R2, and indirectly control the output voltage of the first transfer high-voltage output terminal 1THV. Through this embodiment, it can not only be ensured that during the first transfer process, the high voltage carried by the image carrier 101 cannot be backflowed through the first transfer component to the output end of the first transfer high voltage circuit, thereby causing the output end of the first transfer high voltage circuit to be overloaded and unable to start normally to output the first transfer high voltage, resulting in the printed image being lighter or even having white spots, thereby ensuring the quality of the printed image and improving the user experience, but also the control signal size can be accurately adjusted by the feedback of the voltage value of the first transfer high voltage output end, avoiding the deviation of the control signal due to the influence of the accuracy of the voltage regulator diode, thereby achieving accurate control of the voltage value of the first transfer high voltage output point, making the imaging process more stable.
[0071] During the imaging process, since the charger 112 needs to contact the image carrier 101 for charging, and during the first transfer process, the primary transfer component 102 contacts the image carrier 101 through the intermediate transfer body 107, the transfer positive voltage carried by the primary transfer component 102 may be transmitted to the image carrier 101, and then backflow to the output end of the charging high-voltage circuit of the charger 112, causing the charging high-voltage circuit to overload and fail to work normally. In order to solve the problem of the primary transfer positive high voltage backflowing into the charging high-voltage circuit, as shown in FIG. Figure 6 As shown, the anode terminal of the voltage-stabilizing diode ZD1 is connected to the filter capacitor C3 and the feedback resistor R2 of the voltage-doubling module 230, and the cathode terminal is connected to the charging high-voltage output terminal MHV. Since the backflow of the primary transfer positive high voltage is smaller than the voltage-stabilizing value of the voltage-stabilizing diode ZD1, the voltage-stabilizing diode ZD1 will not be broken down. Therefore, it is possible to prevent the primary transfer positive high voltage from backflowing into the output terminal of the charging high-voltage circuit, causing the charging high-voltage circuit to be overloaded and unable to start normally. Other modules are consistent with the above-mentioned embodiments and will not be described in detail here.
[0072] Since the voltage stabilization accuracy of the voltage stabilization value of the voltage stabilization diode ZD1 may have errors, it is impossible to achieve accurate regulation of the voltage value of the charging high voltage output terminal MHV. Figure 7As shown, the anode terminal of the voltage zener diode ZD1 is connected to the filter capacitor C3 of the voltage doubling module 230, and the cathode terminal is connected to the feedback resistor R2 and the charging high voltage output terminal MHV. By directly transmitting the voltage value of the charging high voltage output terminal MHV to the reverse input terminal of the operational amplifier U1B of the medium and high voltage driving module 210, it is used as the second input source of the operational amplifier U1B. When the charging high voltage circuit is turned on, the control module 106 can accurately control the size of the control signal MHV PWM through the voltage value at the connection between the charging high voltage output terminal MHV and the feedback resistor R2, and through the real voltage value of the charging high voltage output terminal MHV, thereby indirectly controlling the output voltage of the charging high voltage output terminal MHV. The size of the control signal MHV PWM is accurately controlled by the real voltage value of the charging high voltage output terminal MHV, thereby indirectly controlling the output voltage of the charging high voltage output terminal MHV.
[0073] The embodiment of the present application also provides an image forming device, which includes an image carrier 101 for carrying a toner image; a primary transfer component 102 for transferring the toner image on the image carrier 101 to an intermediate transfer body; and an intermediate transfer body 107 for carrying the toner image transferred from the image carrier 101 at the primary transfer position. During the imaging process, the primary transfer component 102 is powered by the primary transfer high-voltage circuit described in any of the above embodiments. During the first transfer process, the surface of the image carrier 101 is in contact with the intermediate transfer body 107 and the primary transfer component 102. The primary transfer high-voltage circuit intercepts the negative high voltage carried by the surface of the image carrier 101 through a voltage stabilizing diode, thereby avoiding the problem that the primary transfer high-voltage output terminal is overloaded due to the backflow of the negative high voltage, resulting in failure to start normally and abnormal printing of the image.
[0074] The above are only some embodiments of the present invention. For those skilled in the art, several modifications and improvements can be made without departing from the creative concept of the present invention, which all belong to the protection scope of the present invention.
Claims
1. A high voltage circuit, characterized in that: Applicable to image forming devices, including: Control module; A high-voltage driving module, the input end of which is connected to the output end of the control module, and is used to control the output of the driving voltage according to the control signal; A high-voltage conversion module, the input end of which is connected to the output end of the high-voltage driving module, and is used to convert the output voltage of the high-voltage driving module into an alternating high-voltage sine wave and output it; A voltage doubling module, the input end of which is connected to the output end of the high-voltage conversion module, and is used to convert the alternating high-voltage sine wave output by the high-voltage conversion module into a voltage of a predetermined volt value; A voltage protection module, the input end of the voltage protection module is connected to the output end of the voltage doubling module, the output end of the voltage protection module is used to connect an external component, and the voltage protection module is used to prevent the voltage received by the external component from flowing back into the high-voltage circuit.
2. The high voltage circuit according to claim 1, characterized in that: The voltage protection module is a voltage stabilizing module, the input end of the voltage stabilizing module serves as the input end of the voltage protection module, and the output end of the voltage stabilizing module serves as the output end of the voltage protection module.
3. The high voltage circuit according to claim 2, characterized in that: The voltage stabilizing module comprises a voltage stabilizing diode, a first end of the voltage stabilizing diode serves as an input end of the voltage stabilizing module, and a second end of the voltage stabilizing diode serves as an output end of the voltage stabilizing module.
4. The high voltage circuit according to claim 3, characterized in that: The cathode end of the voltage stabilizing diode is connected to the output end of the voltage doubling module as the input end of the voltage stabilizing module, and the anode end of the voltage stabilizing diode is connected to the external component as the output end of the voltage stabilizing module.
5. The high voltage circuit according to claim 3, characterized in that: The anode terminal of the voltage stabilizing diode is connected to the output terminal of the voltage doubling module as the input terminal of the voltage stabilizing module, and the cathode terminal of the voltage stabilizing diode is connected to the external component as the output terminal of the voltage stabilizing module.
6. The high voltage circuit according to claim 1, characterized in that: The external component is a primary transfer component, a charger, a developing component, or a fixing assembly of the image forming apparatus.
7. The high voltage circuit according to claim 1, characterized in that: Also includes: A feedback module, wherein the input end of the feedback module is connected to the output end of the voltage doubling module, and the output end of the feedback module is connected to the feedback end of the high-voltage driving module, and is used to feed back the voltage output by the voltage doubling module to the high-voltage driving module.
8. The high voltage circuit according to claim 1, characterized in that: Also includes: A feedback module, wherein the input end of the feedback module is connected to the output end of the voltage protection module, and the output end of the feedback module is connected to the feedback end of the high-voltage driving module, and is used to feed back the voltage output by the voltage protection module to the high-voltage driving module.
9. The high voltage circuit according to any one of claims 7 or 8, characterized in that: The high-voltage driving module includes an operational amplifier driving unit, a first input end of the operational amplifier driving unit serves as an input end of the high-voltage driving module, and a second input end of the operational amplifier driving unit serves as a feedback end of the high-voltage driving module.
10. An image forming device, characterized in that: include: An image carrier for carrying a toner image; A primary transfer member, used for transferring the toner image on the image carrier to an intermediate transfer body; an intermediate transfer body for carrying the toner image transferred from the image bearing body at the primary transfer position; in, The primary transfer component is powered by the high-voltage circuit according to any one of claims 1 to 9, and a voltage protection module of the high-voltage circuit is used to prevent the voltage of the intermediate transfer body from flowing back through the primary transfer component.