Control method and device, storage medium and program product

Abstract

The invention provides a control method and device of an image forming device, a storage medium and a program product. The method comprises the following steps: acquiring a historical coverage rate of a photosensitive drum; and if the historical coverage rate and the historical coverage rate threshold meet the preset relation, the transfer printing voltage of the secondary transfer printing roller is adjusted from the first transfer printing voltage to the second transfer printing voltage. In other words, it is determined whether the image forming apparatus performs a low-coverage image forming operation or a small-paper-type image forming operation for a long period of time through the historical coverage. When it is judged that the image forming device conducts low-coverage-rate image forming operation or small-paper-type image forming operation for a long time, the secondary transfer printing voltage of the secondary transfer printing roller is adjusted, the poor transfer printing phenomenon caused by the too high secondary transfer printing voltage is reduced as much as possible, the secondary transfer printing effect is improved, and then the portrait quality is improved.

Description

Technical Field

[0001] The present application relates to the field of image forming technology, and in particular to a control method, device, storage medium and program product for image formation. Background Art

[0002] The image forming apparatus is a device that forms an image on a recording sheet by the imaging principle, such as a printer, a copier, a fax machine, a multifunctional image making and copying apparatus, an electrostatic printing apparatus, and any other similar apparatus.

[0003] The image forming device usually includes functional modules such as a laser scanning unit, a photosensitive drum, a developing roller, a powder feeding roller, a primary transfer roller, an intermediate transfer unit, and a secondary transfer roller. Its working principle is as follows: when the image forming device performs an image forming operation, an electrostatic latent image is formed on the surface of the photosensitive drum through scanning by the laser scanning unit; the developing roller attaches the toner transported by the powder feeding roller to the electrostatic latent image area on the surface of the photosensitive drum to form a toner image; under the action of the primary transfer roller, the toner image on the surface of the photosensitive drum is transferred to the intermediate transfer unit, and this process is called "primary transfer"; under the action of the secondary transfer roller, the toner image on the intermediate transfer unit is transferred to the recording sheet, and this process is called "secondary transfer".

[0004] In actual applications, the applicant has found that when a low coverage image forming operation or a small paper size image forming operation is performed for a long time, secondary transfer failure may occur, resulting in poor image quality.

[0005] It should be pointed out that the information disclosed in the background technology section of this application is only intended to deepen the understanding of the general background technology of this application, and should not be regarded as an admission or suggestion in any form that the information constitutes prior art already known to those skilled in the art. Summary of the invention

[0006] The present application provides a control method, device, storage medium and program product for an image forming device, so as to solve the problem in the prior art that when a low-coverage image forming operation or a small-paper image forming operation is performed for a long time, secondary transfer failure will occur, thereby resulting in poor image quality.

[0007] In a first aspect, an embodiment of the present application provides a method for controlling an image forming device, comprising: Acquire a historical coverage rate of the photosensitive drum, wherein the historical coverage rate is the average number of ink dots of an image forming operation corresponding to each page of the image forming job in the completed image forming job; If the historical coverage rate and the historical coverage rate threshold value satisfy a preset relationship, adjusting the transfer voltage of the secondary transfer roller from the first transfer voltage to the second transfer voltage; The secondary transfer roller is used to transfer the toner image on the intermediate transfer unit to the recording sheet.

[0008] In a possible implementation, there are multiple photosensitive drums; The obtaining of the historical coverage of the photosensitive drum comprises: obtaining the historical coverage of each of the plurality of photosensitive drums; If the historical coverage rate and the historical coverage rate threshold satisfy a preset relationship, the transfer voltage of the secondary transfer roller is adjusted from the first transfer voltage to the second transfer voltage, including: if the historical coverage rate and the historical coverage rate threshold of any one of the photosensitive drums satisfy a preset relationship, the transfer voltage of the secondary transfer roller is adjusted from the first transfer voltage to the second transfer voltage.

[0009] In a possible implementation, adjusting the transfer voltage of the secondary transfer roller from the first transfer voltage to the second transfer voltage includes: According to the number of pages of the completed image forming job, the first transfer voltage of the secondary transfer roller is adjusted to obtain the second transfer voltage; adjusting the transfer voltage of the secondary transfer roller to the second transfer voltage; The number of pages of the completed image forming job is negatively correlated with the second transfer voltage.

[0010] In a possible implementation, adjusting the first transfer voltage of the secondary transfer roller according to the number of pages of the completed image forming job to obtain the second transfer voltage includes: If the number of pages of the completed image forming job and the threshold of the number of pages of the image forming job satisfy a preset relationship, adjusting the first transfer voltage of the secondary transfer roller according to the number of pages of the completed image forming job to obtain a second transfer voltage; If the number of pages of the completed image forming job does not satisfy a preset relationship with the image forming job page number threshold, the first transfer voltage of the secondary transfer roller is adjusted according to the image forming job page number threshold to obtain a second transfer voltage.

[0011] In a possible implementation, adjusting the transfer voltage of the secondary transfer roller from the first transfer voltage to the second transfer voltage includes: adjusting a first transfer voltage of the secondary transfer roller to obtain a second transfer voltage; If the second transfer voltage satisfies a preset relationship with the transfer voltage threshold, adjusting the transfer voltage of the secondary transfer roller to the transfer voltage threshold; If the second transfer voltage and the transfer voltage threshold do not satisfy a preset relationship, the transfer voltage of the secondary transfer roller is adjusted to the second transfer voltage.

[0012] In a possible implementation, the toner image on the photosensitive drum is used to transfer to the intermediate transfer unit, and the method further includes: The linear velocity of the photosensitive drum is controlled to be greater than or equal to the linear velocity of the developing roller and / or the linear velocity of the intermediate transfer unit.

[0013] In a possible implementation, there are multiple photosensitive drums, and the number of pages on which image forming jobs have been completed is an average value of the number of pages on which image forming jobs have been completed by the multiple photosensitive drums.

[0014] In a second aspect, an embodiment of the present application provides an image forming device, including: A controller, wherein the controller is configured to execute the method described in any one of the first aspects.

[0015] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described in any one of the first aspects is implemented.

[0016] In a fourth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the method described in any one of the first aspects.

[0017] The applicant has found through research that when a low-coverage image forming operation or a small-paper image forming operation is performed for a long time, the toner near the developing roller cannot be transferred to the intermediate transfer unit in time, which will cause toner accumulation. In the process of performing the image forming operation, the photosensitive drum, developing roller, powder feeding roller and other components are always in a rotating state. The accumulated toner and the friction between the above components will cause the physical properties of the toner to change, which will lead to poor secondary transfer and reduced image quality. In theory, the higher the secondary transfer voltage, the higher the mobility of the toner and the better the secondary transfer effect. However, in the actual secondary transfer process, an excessively high transfer voltage will cause the electrical properties of the toner to change, which will again affect the transfer effect and cause a reduction in image quality.

[0018] In an embodiment of the present application, it is determined by historical coverage whether the image forming device has been performing low-coverage image forming operations or small-paper image forming operations for a long time, and whether the secondary transfer voltage needs to be adjusted. When the secondary transfer voltage needs to be adjusted, the secondary transfer voltage of the secondary transfer roller is lowered to minimize the poor transfer effect and poor image quality caused by excessively high secondary transfer voltage, thereby improving the secondary transfer effect and the image quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Figure 1 A schematic diagram of the structure of an image forming device provided in an embodiment of the present application.

[0021] Figure 2 A flowchart of a control method for an image forming device provided in an embodiment of the present application.

[0022] Figure 3 A schematic flow chart of another method for controlling an image forming device provided in an embodiment of the present application.

[0023] Figure 4 A schematic flow chart of another method for controlling an image forming device provided in an embodiment of the present application.

[0024] Figure 5 A schematic flow chart of another method for controlling an image forming device provided in an embodiment of the present application.

[0025] Figure 6 A schematic diagram of force analysis of a photosensitive drum provided in an embodiment of the present application.

[0026] Figure 7 A schematic flow chart of another method for controlling an image forming device provided in an embodiment of the present application.

[0027] Figure 8 A schematic diagram of the structure of another image forming device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] To facilitate understanding, the specific structure and working principle of the image forming device are first exemplarily described below.

[0033] See also Figure 1 , is a schematic diagram of the structure of an image forming device provided in an embodiment of the present application. The image forming device 100 is used to perform image forming tasks, such as generating, printing, receiving and sending image data, and examples of the image forming device 100 include printers, scanners, copiers, fax machines, and multi-function peripherals (MFP, Multi-Functional Peripheral) that perform the above functions in a single device.

[0034] As an example of an image forming apparatus 100, the image forming apparatus 100 includes a photosensitive drum 101Y-K, a charging roller 102Y-K, a developing roller 103Y-K, a powder hopper 104Y-K, a transfer belt 105, a secondary transfer roller 106, a paper supply box 107, a manual paper feed tray 108, a pickup roller 109, a conveying roller 110, a paper detection sensor 120, a laser scanning unit (LSU, Laser Scanning Unit) 111, a heat roller 112, a pressure roller 113, a discharge roller 114, a discharge paper box 115, a powder feeding roller 116Y-K, and a primary transfer roller 117Y-K. Generally speaking, the process box YK includes a photosensitive drum 101Y-K, a charging roller 102Y-K, a developing roller 103Y-K, a powder hopper 104Y-K for holding toner, and a powder feeding roller 116Y-K.

[0035] LSU 111 is in the form of a single LSU, including four optical paths. Four charging rollers 102Y-K are used to charge the surfaces of four photosensitive drums 101Y-K respectively, and four powder feeding rollers 116Y-K are used to feed toner to four developing rollers 103Y-K respectively. The four optical paths of LSU 111 respectively emit laser beams to form electrostatic latent images on the surfaces of photosensitive drums 101Y-K, and the four developing rollers 103Y-K are used to develop and form a color toner image on the surfaces of photosensitive drums 101Y-K respectively. The image forming device 100 adopts a secondary transfer method, that is, the four photosensitive drums 101Y-K sequentially transfer the toner image to the transfer belt 105 via the primary transfer rollers 117Y-K, and then the color toner image formed on the transfer belt 105 is secondary transferred to the paper P via the secondary transfer rollers 106. The paper feed box 107 is used to store paper P, and the pickup roller 109 is used to transport the paper P stored in the paper feed box 107 to a transport path (hereinafter referred to as a paper path). The transport roller 110 is used to transport the paper P to the secondary transfer roller 106 .

[0036] The secondary transfer roller 106 conveys the imaged paper P to the clamping area of ​​the heat roller 112 and the pressure roller 113. The heat roller 112 and the pressure roller 113 are used to fix the toner image on the paper P. The heat roller 112 can adopt a ceramic heating method. The heat roller 112 and the pressure roller 113 convey the fixed paper P to the discharge roller 114. The discharge roller 114 discharges the paper P to the discharge paper box 115 and stacks it.

[0037] The laser scanning unit 111 obtains the optical analog image signal of the original / source document by exposing the optical print head. The paper detection sensor 120 is used to detect whether there is paper P in the paper path where it is located.

[0038] The paper supply box 107 is provided with a paper outlet, and the pickup roller 109 is specifically used to send the paper P contained in the paper supply box 107 from the paper outlet into the paper path channel for transfer needs. The image forming device 100 also includes a driving mechanism (not shown) for driving the pickup roller 109 to work. The driving mechanism is a driving motor, which is used to drive the pickup roller 109 to move to achieve the paper pickup operation. The driving mechanism 181 is electrically connected to the controller of the image forming device (not shown) to realize the controller's control of the driving mechanism. The controller is electrically connected to the paper detection sensor 120, and the paper detection sensor sends the detection result information of whether there is paper P on the paper path channel to the controller.

[0039] Image forming apparatus 100 further includes an operation panel (not shown), and the operation panel includes an operation unit (not shown) including various keys and a touch panel type display unit (not shown).

[0040] It can be understood that the image forming apparatus 100 listed above is only an example, and the component composition and component arrangement of the image forming apparatus 100 can be adjusted according to actual conditions without affecting the improvement ideas of the present invention.

[0041] It should be pointed out that Figure 1 The transfer belt 105 is only a specific implementation of the intermediate transfer unit provided in the embodiment of the present application. In practical applications, those skilled in the art can set other types of intermediate transfer units according to actual needs. In addition, the recording sheet may be made of other materials besides paper, and the embodiment of the present application does not make any specific restrictions on this.

[0042] As described above, when the image forming device performs an image forming operation, an electrostatic latent image is formed on the surface of the photosensitive drum through scanning by the laser scanning unit; the powder feeding roller conveys the toner in the powder bin to the developing roller, and the developing roller attaches the toner to the electrostatic latent image area on the surface of the photosensitive drum to form a toner image; under the action of the primary transfer roller, the toner image on the surface of the photosensitive drum is transferred to the intermediate transfer unit, and this process is called "primary transfer"; under the action of the secondary transfer roller, the toner image on the intermediate transfer unit is transferred to the recording sheet, and this process is called "secondary transfer".

[0043] In actual applications, the powder feeding roller conveys the toner in the powder bin to the developing roller at a certain rate. When the photosensitive drum performs low-coverage image forming operations or small-paper image forming operations for a long time, the toner near the developing roller cannot be transferred to the intermediate transfer unit in time, which will cause toner accumulation. In the process of performing image forming operations, the photosensitive drum, developing roller, powder feeding roller and other parts are always in a rotating state. The accumulated toner and the friction between the above parts will cause the amount of charge carried by the toner to increase. In the process of secondary transfer, the electric field force required to transfer the toner from the intermediate transfer unit to the recording sheet is constant. Due to the increase in the amount of charge carried by the toner, the secondary transfer is poor and the image quality is reduced.

[0044] Theoretically, the higher the secondary transfer voltage, the higher the mobility of the toner and the better the transfer effect. However, in the actual secondary transfer process, an excessively high secondary transfer voltage will cause the electrical properties of the toner to change, which will again affect the transfer effect and lead to a decrease in image quality.

[0045] In response to the above-mentioned problems, in an embodiment of the present application, it is determined through historical coverage whether the image forming device has been performing low-coverage image forming operations or small-paper image forming operations for a long time, and whether the secondary transfer voltage needs to be adjusted. When the secondary transfer voltage needs to be adjusted, the secondary transfer voltage of the secondary transfer roller is lowered to minimize the poor transfer effect and poor image caused by excessively high secondary transfer voltage, thereby improving the secondary transfer effect and improving the image quality.

[0046] Specifically, a detailed description is given below in conjunction with the accompanying drawings and specific embodiments.

[0047] See also Figure 2 , is a flow chart of a control method for an image forming device provided in an embodiment of the present application. The method can be applied to Figure 1 The image forming device shown in Figure 2 As shown, it specifically includes the following steps.

[0048] Step S201: Obtain the historical coverage of the photosensitive drum.

[0049] In actual applications, when the image forming device performs low-coverage image forming operations or small-paper image forming operations for a long time, it will lead to poor secondary transfer and poor image quality. Therefore, when the user issues an image forming task, it is necessary to determine whether the image forming device performs low-coverage image forming operations or small-paper image forming operations for a long time.

[0050] In order to determine whether the image forming device has been performing low coverage image forming operations or small paper size image forming operations for a long time, in the embodiment of the present application, after the user issues an image forming task, the historical coverage of the photosensitive drum is first obtained. The historical coverage is the average number of ink dots of the image forming operation corresponding to each page of the image forming operation in the completed image forming operation. Through the historical coverage, it can be determined whether the image forming device has been performing low coverage image forming operations or small paper size image forming operations for a long time.

[0051] Specifically, when the image forming device performs low coverage image forming operations for a long time, it will result in a low historical coverage. The "coverage" refers to the percentage of the area of ​​the recording sheet covered by toner to the total area of ​​the recording sheet. The area of ​​the recording sheet covered by toner is related to the number of ink dots. Generally speaking, the smaller the area of ​​the recording sheet covered by toner, the fewer the number of ink dots, and the lower the coverage. When the image forming device performs low coverage image forming operations for a long time, the average number of ink dots in the image forming operation corresponding to each page of image forming operation is small, that is, the historical coverage is low.

[0052] When the image forming device performs a small-paper image forming operation for a long time, the historical coverage rate will also be low. It can be understood that when the image forming device performs a small-paper image forming operation for a long time, since the total area of ​​the recording sheet of the small-paper is small, even if the image forming device performs a high-coverage image forming operation, the average number of ink dots of the image forming operation corresponding to each page of image forming job is still small, that is, the historical coverage rate is low.

[0053] In a possible implementation, the number of pages of the completed image forming job and the number of ink dots of the completed image forming operation can be first obtained, and then the number of ink dots of the completed image forming operation is divided by the number of pages of the completed image forming job to obtain the historical coverage rate. Exemplarily, when the number of pages of the completed image forming job is N and the number of ink dots of the completed image forming operation is Q, the historical coverage rate is Q / N. Step S202: If the historical coverage rate and the historical coverage rate threshold meet the preset relationship, the transfer voltage of the secondary transfer roller is adjusted from the first transfer voltage to the second transfer voltage.

[0054] Specifically, the preset relationship between the historical coverage rate and the threshold of the historical coverage rate is: the historical coverage rate is less than or equal to the historical coverage rate threshold. In an embodiment of the present application, in order to determine whether the image forming device performs low-coverage image forming operations or small-paper image forming operations for a long time based on the historical coverage rate, a historical coverage rate threshold can be preset. After obtaining the historical coverage rate, the historical coverage rate and the historical coverage rate threshold are compared, and based on the comparison result, it is determined whether the image forming device performs low-coverage image forming operations or small-paper image forming operations for a long time. Specifically, if the historical coverage rate is less than or equal to the preset historical coverage rate threshold, it is determined that the image forming device performs low-coverage image forming operations or small-paper image forming operations for a long time; on the contrary, if the historical coverage rate is greater than the preset historical coverage rate threshold, it is determined that the image forming device does not perform low-coverage image forming operations and small-paper image forming operations for a long time.

[0055] Among them, the historical coverage rate threshold can be 1068 kilopoints, 1780 kilopoints, 2848 kilopoints, 3560 kilopoints, 5340 kilopoints, etc. Technical personnel in this field can make adaptive choices according to actual needs, or set other historical coverage rate thresholds. The embodiments of the present application do not impose specific restrictions on this.

[0056] As described above, when the image forming device performs a low coverage image forming operation or a small paper image forming operation for a long time, failure to adjust the secondary transfer voltage may result in poor secondary transfer and thus poor image quality. Therefore, in the embodiment of the present application, when it is determined that the image forming device performs a low coverage image forming operation or a small paper image forming operation for a long time, the transfer voltage of the secondary transfer roller is adjusted from the first transfer voltage to the second transfer voltage.

[0057] In one embodiment, the first transfer voltage is greater than the second transfer voltage.

[0058] It should be noted that, in the embodiment of the present application, the first transfer voltage is the default transfer voltage when the image forming device performs an image forming operation. The first transfer voltages of image forming devices of different models may be the same or different, and the embodiment of the present application does not impose any specific limitation on this.

[0059] In practical applications, when the image forming device performs low coverage image forming operation or small paper size image forming operation for a long time, if the first transfer voltage is not adjusted, the transfer voltage of the secondary transfer roller will be too high, thereby affecting the secondary transfer effect. Therefore, it is necessary to adjust the first transfer voltage. It can be understood that the adjusted second transfer voltage is lower than the first transfer voltage.

[0060] In the embodiment of the present application, it is determined by the historical coverage whether the image forming device performs low coverage image forming operation or small paper size image forming operation for a long time. When it is determined that the image forming device performs low coverage image forming operation or small paper size image forming operation for a long time, the secondary transfer voltage of the secondary transfer roller is adjusted to reduce the transfer failure and poor image quality caused by the excessively high secondary transfer voltage as much as possible, improve the secondary transfer effect, and then improve the image quality.

[0061] See also Figure 3 , is a flow chart of another control method of an image forming device provided in an embodiment of the present application. Figure 3 As shown, the embodiment of the present application is Figure 2 Based on the illustrated embodiment, step S202 specifically includes the following steps.

[0062] Step S301: if the historical coverage rate and the historical coverage rate threshold value satisfy a preset relationship, the first transfer voltage of the secondary transfer roller is adjusted according to the number of pages of the completed image forming job to obtain a second transfer voltage.

[0063] In actual applications, when it is determined that the image forming device performs low-coverage image forming operations or small-paper image forming operations for a long time, the more pages that have completed the image forming job, the longer the friction time between the accumulated toner near the developing roller and the related components, which may lead to the accumulation of toner on both sides of the powder outlet and cause the physical properties of the accumulated toner (such as charging ability) to change.

[0064] It is understood that during the secondary transfer process, the physical properties of the toner change, the transfer effect changes, and the image quality presented on the recording sheet changes. Therefore, the transfer voltage of the secondary transfer roller can be adjusted according to the number of pages of the completed image forming job.

[0065] Specifically, the second transfer voltage of the secondary transfer roller can be determined according to the formula: V2=V1-(D×α). Wherein, V2 is the second transfer voltage, V1 is the first transfer voltage, D is the number of pages of the completed image forming job, and α is the adjustment coefficient. According to the above formula, the number of pages of the completed image forming job is negatively correlated with the second transfer voltage.

[0066] In a specific implementation, α can be 0.4, 0.5, 0.6, etc. Those skilled in the art can make an adaptive selection according to actual needs, or set other adjustment coefficients. The embodiments of the present application do not impose specific limitations on this.

[0067] As mentioned above, the number of pages of the completed image forming job is negatively correlated with the second transfer voltage. That is, the more pages of the completed image forming job, the smaller the second transfer voltage. However, if the second transfer voltage is too small, it may result in failure to complete the normal secondary transfer. Therefore, in the embodiment of the present application, a threshold value of the number of pages of the image forming job is set, and it is determined whether the number of pages of the completed image forming job and the threshold value of the number of pages of the image forming job meet a preset relationship, and the preset relationship is that the number of pages of the image forming job is less than or equal to the threshold value of the image forming job; then, the second transfer voltage is determined according to the judgment result.

[0068] It should be noted that the image forming job page number threshold may be 4500, 5000, 5500, etc., and those skilled in the art may make an adaptive selection according to actual needs, or set other image forming job page number thresholds. Of course, the image forming job page number threshold may also be the maximum number of pages of image forming jobs that the image forming device can complete the image forming operation. The embodiments of the present application do not impose specific restrictions on this.

[0069] In one possible implementation, if the number of pages of the completed image forming job is less than or equal to a preset image forming job page number threshold, the first transfer voltage of the secondary transfer roller is adjusted according to the number of pages of the completed image forming job to obtain the second transfer voltage; if the number of pages of the completed image forming job is greater than the image forming job page number threshold, the first transfer voltage of the secondary transfer roller is adjusted according to the image forming job page number threshold to obtain the second transfer voltage.

[0070] Exemplarily, the threshold value of the number of pages of the image forming job is 5000. When the number of pages of the completed image forming job is 4500, since 4500<5000, that is, the number of pages of the completed image forming job is less than the threshold value of the number of pages of the image forming job, at this time, the second transfer voltage V2=V1-(4500×α); when the number of pages of the completed image forming job is 5000, since 5000=5000, that is, the number of pages of the completed image forming job is equal to the threshold value of the number of pages of the image forming job, at this time, the second transfer voltage V2=V1-(5000×α). When the number of pages of the completed image forming job is 5500, since 5500>5000, that is, the number of pages of the completed image forming job is greater than the threshold value of the number of pages of the image forming job, at this time, the second transfer voltage V2=V1-(5000×α).

[0071] It can be understood that when the number of pages of the completed image forming job is greater than the image forming job page number threshold, the number of pages of the completed image forming job can be set as the image forming job page number threshold; and then the second transfer voltage is determined according to the above formula.

[0072] In an embodiment of the present application, when the number of pages of the completed image forming job exceeds the image forming job page number threshold, the second transfer voltage is determined based on the image forming job page number threshold, which can avoid the second transfer voltage being too low and ensure the image quality to a certain extent.

[0073] In addition, the number of photosensitive drums in the image forming device may be multiple. Each photosensitive drum corresponds to a color of toner. For example, a color image forming device may include four photosensitive drums, each corresponding to black, magenta, cyan and yellow. Of course, the number of photosensitive drums in the image forming device may be two, three, etc., and those skilled in the art can make adaptive choices according to actual needs, or set other numbers of photosensitive drums, and the embodiments of the present application do not make specific restrictions on this.

[0074] In one embodiment, when there are multiple photosensitive drums in the image forming device, the number of pages of the completed image forming jobs corresponding to different photosensitive drums may be the same or different. In the example of the present application, the average number of pages of the image forming jobs completed by the multiple photosensitive drums is taken as the number of pages of the completed image forming jobs.

[0075] For example, Figure 1 The image forming apparatus shown in the figure includes a photosensitive drum K, a photosensitive drum M, a photosensitive drum C, and a photosensitive drum Y. If the number of pages of the completed image forming job of the photosensitive drum KY is N, respectively k 、N m 、N c and N y , then the number of pages D of the completed image forming job is (N k +N m +N c +N y ) / 4.

[0076] In the embodiment of the present application, when there are multiple photosensitive drums in the image forming device, the average number of pages of the completed image forming job of each photosensitive drum is calculated, and the number of pages of the completed image forming job of each photosensitive drum is comprehensively considered to determine the transfer voltage suitable for each photosensitive drum, thereby ensuring the image quality. Step S302: Adjust the transfer voltage of the secondary transfer roller to the second transfer voltage.

[0077] In the embodiment of the present application, after the second transfer voltage is obtained, the transfer voltage of the secondary transfer roller is adjusted to the second transfer voltage. Under the action of the second transfer voltage, the overly high secondary transfer voltage is reduced as much as possible to cause the denatured toner to produce poor transfer during the secondary transfer, thereby allowing the toner on the intermediate transfer unit to be normally transferred to the recording sheet.

[0078] In the embodiment of the present application, a more accurate second transfer voltage can be determined according to the number of pages of the completed image forming job, thereby improving the secondary transfer effect and further improving the image quality.

[0079] It should be noted that other contents involved in the embodiments of the present application can be found in the above Figure 2 For the sake of brevity, the description in the illustrated embodiment will not be repeated here.

[0080] See also Figure 4 , is a flow chart of another control method of an image forming device provided in an embodiment of the present application. Figure 4 As shown, in Figure 2 Based on the illustrated embodiment, step S202 specifically includes the following steps.

[0081] Step S401: If the historical coverage rate and the historical coverage rate threshold satisfy a preset relationship, the first transfer voltage of the secondary transfer roller is adjusted to obtain a second transfer voltage.

[0082] In the embodiment of the present application, it is determined whether the image forming device performs a low coverage image forming operation or a small paper size image forming operation for a long time by using the historical coverage rate. If the historical coverage rate and the historical coverage rate threshold value satisfy a preset relationship, and the preset relationship is that the historical coverage rate is less than or equal to the historical coverage rate threshold value, it means that the image forming device performs a low coverage image forming operation or a small paper size image forming operation for a long time, then the first transfer voltage of the secondary transfer roller is adjusted to obtain the second transfer voltage.

[0083] However, if the second transfer voltage is too low, it may result in failure to complete normal secondary transfer. Therefore, in the embodiment of the present application, it is necessary to first determine whether the second transfer voltage is too low. In one possible implementation, a transfer voltage threshold can be set, and it can be determined whether the second transfer voltage and the transfer voltage threshold satisfy a preset relationship, where the preset relationship is that the second transfer voltage is less than or equal to the transfer voltage threshold; then, the second transfer voltage is determined based on the judgment result.

[0084] It should be pointed out that the transfer voltage threshold may be 800V, 1000V, 1200V, etc. Those skilled in the art may make an adaptive selection according to actual needs, or set other transfer voltage thresholds. The embodiments of the present application do not impose specific limitations on this.

[0085] Step S402: If the second transfer voltage and the transfer voltage threshold satisfy a preset relationship, the transfer voltage of the secondary transfer roller is adjusted to the transfer voltage threshold.

[0086] Specifically, the preset relationship is that the second transfer voltage is less than or equal to the transfer voltage threshold. In the embodiment of the present application, if the second transfer voltage and the transfer voltage threshold satisfy the preset relationship, it means that the image forming device cannot complete the normal secondary transfer or can just meet the normal secondary transfer, then the transfer voltage of the secondary transfer roller can be adjusted to the transfer voltage threshold.

[0087] Step S403: If the second transfer voltage and the preset transfer voltage threshold do not satisfy a preset relationship, the transfer voltage of the secondary transfer roller is adjusted to the second transfer voltage.

[0088] Specifically, the preset condition is that the second transfer voltage is less than or equal to the transfer voltage threshold.

[0089] It can be understood that if the second transfer voltage and the transfer voltage threshold do not satisfy the preset relationship, it can be considered that the second transfer voltage can enable the image forming device to complete the secondary transfer normally, and the transfer voltage of the secondary transfer roller is adjusted to the second transfer voltage.

[0090] In the embodiment of the present application, when the second transfer voltage is too low, the transfer voltage of the secondary transfer roller is adjusted to the minimum value of the transfer voltage, which can prevent the second transfer voltage from being too low and the transfer effect from being poor, thereby improving the image quality to a certain extent.

[0091] It should be noted that other contents involved in the embodiments of the present application can be found in the above Figures 2 to 4 The description in the illustrated embodiment is omitted for brevity. Before performing the secondary transfer, it is necessary to ensure that the primary transfer effect is good. Figure 5 , is a flow chart of another control method of an image forming device provided in an embodiment of the present application. Figure 5 As shown, the embodiment of the present application is Figure 2 Based on the illustrated embodiment, the following steps are also included.

[0092] Step S500: controlling the linear velocity of the photosensitive drum to be greater than or equal to the linear velocity of the developing roller and / or the linear velocity of the intermediate transfer unit.

[0093] As mentioned above, the developing roller is used to form a toner image on the surface of the photosensitive drum, and the toner image on the photosensitive drum is used to be transferred to the intermediate transfer unit. It can be understood that the photosensitive drum is in contact with the developing roller and the intermediate transfer unit.

[0094] In actual application, when the linear velocity of the photosensitive drum is less than the linear velocity of the developing roller and / or the intermediate transfer unit, the direction of the friction force on the photosensitive drum by the developing roller and / or the intermediate transfer unit is the same as the rotation direction of the photosensitive drum.

[0095] See also Figure 6 , is a schematic diagram of force analysis of a photosensitive drum provided in an embodiment of the present application. Figure 6 As shown, the photosensitive drum 101 is in contact with the developing roller 103 and the transfer belt 105. The photosensitive drum 101 rotates clockwise at a linear velocity of V1, the developing roller 103 rotates counterclockwise at a linear velocity of V3, and the transfer belt 105 rotates counterclockwise at a linear velocity of V5. When the linear velocity V1 of the photosensitive drum 101 is less than the linear velocity V3 of the developing roller 103, the direction of the friction force f3 of the developing roller 103 on the photosensitive drum 101 is the same as the direction of rotation of the photosensitive drum 101; when the linear velocity V1 of the photosensitive drum 101 is less than the linear velocity V5 of the transfer belt 105, the direction of the friction force f5 of the transfer belt 105 on the photosensitive drum 101 is the same as the direction of rotation of the photosensitive drum 101.

[0096] Since the photosensitive drum is subjected to the same friction force as the rotation direction of the photosensitive drum, it may provide driving force for the photosensitive drum. For example, when the friction force on the photosensitive drum is higher than the driving force of the photosensitive drum itself, the driving force of the photosensitive drum itself cannot provide driving force for the photosensitive drum. At this time, the driving force of the photosensitive drum comes from the developing roller and / or the intermediate transfer unit, rather than the driving force of the photosensitive drum itself, and the photosensitive drum is driven by the developing roller and / or the intermediate transfer unit.

[0097] However, when there is toner between the photosensitive drum and the developing roller and / or the intermediate transfer unit, the friction force on the photosensitive drum from the developing roller and / or the intermediate transfer unit will be reduced due to the lubrication of the toner. When the friction force on the photosensitive drum is lower than the driving force of the photosensitive drum itself, the friction force on the photosensitive drum cannot provide driving force for the photosensitive drum. At this time, the driving force of the photosensitive drum comes from the driving force of the photosensitive drum itself, not the developing roller and / or the intermediate transfer unit, and the photosensitive drum is not driven by the developing roller and / or the intermediate transfer unit.

[0098] As mentioned above, a toner image, i.e., toner, will be formed in the electrostatic latent image area on the surface of the photosensitive drum. It is understandable that there will be no toner in the non-electrostatic latent image area on the surface of the photosensitive drum. Therefore, during the imaging process of the photosensitive drum, the driving force of the photosensitive drum may be unstable, resulting in unstable rotation speed, affecting the primary transfer effect, and further affecting the image quality. Therefore, the linear speed of the photosensitive drum can be controlled to be greater than or equal to the linear speed of the developing roller and / or the linear speed of the intermediate transfer unit, so that the developing roller and the intermediate transfer unit cannot provide driving force for the photosensitive drum.

[0099] It can be understood that when the linear speed of the photosensitive drum is greater than the linear speed of the developing roller and / or the intermediate transfer unit, the friction force of the developing roller and / or the intermediate transfer unit on the photosensitive drum is opposite to the rotation direction of the photosensitive drum, and no driving force can be provided for the photosensitive drum; when the linear speed of the photosensitive drum is equal to the linear speed of the developing roller and / or the intermediate transfer unit, the photosensitive drum and the developing roller and / or the intermediate transfer unit are relatively stationary, and the photosensitive drum will not be driven by the developing roller and / or the intermediate transfer unit, that is, no driving force can be provided for the photosensitive drum.

[0100] In the embodiment of the present application, by controlling the linear velocity of the photosensitive drum to be greater than or equal to the linear velocity of the developing roller and / or the linear velocity of the intermediate transfer unit, the developing roller and / or the intermediate transfer unit can be prevented from providing driving force for the photosensitive drum. Therefore, the stability of the rotation speed of the photosensitive drum is not affected, thereby ensuring the stability of the rotation of the photosensitive drum, making the primary transfer effect good, and ensuring the image quality to a certain extent.

[0101] See also Figure 7 , is a flow chart of another control method of an image forming device provided in an embodiment of the present application. Figure 7 As shown, the embodiment of the present application is Figure 2 On the basis of the illustrated embodiment, step S201 includes step S701, and step S202 includes step S702.

[0102] Step S701: Obtain the historical coverage of each photosensitive drum among the plurality of photosensitive drums.

[0103] In actual applications, an image forming device may include multiple photosensitive drums. When there are multiple photosensitive drums in an image forming device, if one photosensitive drum performs low coverage image forming operation or small paper image forming operation for a long time, secondary transfer failure may occur, affecting the transfer effect and thus resulting in poor image quality.

[0104] For example, Figure 1 The image forming device shown includes four photosensitive drums, namely, photosensitive drum K, photosensitive drum M, photosensitive drum C and photosensitive drum Y. The toner colors corresponding to each photosensitive drum are black, magenta, cyan and yellow respectively. When the photosensitive drum K performs low coverage image forming operation or small paper image forming operation for a long time, the black toner may be reversely transferred, thereby affecting the image quality related to black; when the photosensitive drum K and the photosensitive drum M perform low coverage image forming operation or small paper image forming operation for a long time, the black and magenta toner may be poorly secondary transferred, thereby affecting the image quality related to black and magenta.

[0105] In an embodiment of the present application, when there are multiple photosensitive drums in the image forming device, it is necessary to determine whether there is at least one photosensitive drum that performs a low-coverage image forming operation or a small-paper-size image forming operation for a long time. As described above, in order to determine whether a photosensitive drum performs a low-coverage image forming operation or a small-paper-size image forming operation for a long time, it is necessary to first obtain the historical coverage. It is understandable that in order to determine whether there is at least one photosensitive drum that performs a low-coverage image forming operation or a small-paper-size image forming operation for a long time in the image forming device, it is necessary to obtain the historical coverage of each photosensitive drum.

[0106] As described above, the historical coverage rate can be obtained by the number of ink dots of the completed image forming operation and the number of pages of the completed image forming job. In the embodiment of the present application, in order to obtain the historical coverage rate of each photosensitive drum, it is first necessary to obtain the number of ink dots of the completed image forming operation and the number of pages of the completed image forming job of each photosensitive drum; then, according to the number of ink dots of the completed image forming operation of each photosensitive drum and the number of pages of the completed image forming job of each photosensitive drum, the historical coverage rate of each photosensitive drum is obtained.

[0107] For example, Figure 1 In the image forming apparatus shown in FIG. 1 , when the photosensitive drum K has completed the image forming operation, the number of ink dots is Q. k , the number of pages of the completed image forming job is N k When the historical coverage of the photosensitive drum K is Q k / N k ; When the number of ink dots on the photosensitive drum M that have completed the image forming operation is Q m , the number of pages of the completed image forming job is N m When the historical coverage of the photosensitive drum M is Q m / N m ; When the number of ink dots that the photosensitive drum C has completed the image forming operation is Q c , the number of pages of the completed image forming job is N c When the historical coverage of photosensitive drum C is Q c / N c ; When the number of ink dots on the photosensitive drum Y that have completed the image forming operation is Q y , the number of pages of the completed image forming job is N y When the historical coverage of photosensitive drum Y is Q y / N y .

[0108] Step S702: If the historical coverage of any photosensitive drum satisfies a preset relationship with the historical coverage threshold, the transfer voltage of the secondary transfer roller is adjusted from the first transfer voltage to the second transfer voltage.

[0109] Specifically, the preset relationship between the historical coverage and the threshold of the historical coverage is: the historical coverage is less than or equal to the threshold of the historical coverage. That is, if the historical coverage of any photosensitive drum is less than or equal to the threshold of the historical coverage, the transfer voltage of the secondary transfer roller is adjusted from the first transfer voltage to the second transfer voltage.

[0110] As described above, when there are multiple photosensitive drums in the image forming device, as long as one photosensitive drum performs a low coverage image forming operation or a small paper size image forming operation for a long time, secondary transfer failure may occur, affecting the transfer effect. Therefore, when there are multiple photosensitive drums in the image forming device, it is necessary to determine whether each photosensitive drum performs a low coverage image forming operation or a small paper size image forming operation for a long time.

[0111] In the embodiment of the present application, when it is determined that any one of the plurality of photosensitive drums performs a low-coverage image forming operation or a small-size image forming operation for a long time, the transfer voltage of the secondary transfer roller is reduced.

[0112] In the embodiment of the present application, when there are multiple photosensitive drums in the image forming device, it is determined whether each photosensitive drum in the image forming device is a photosensitive drum that performs low-coverage image forming operation or small-paper image forming operation for a long time through the historical coverage of each photosensitive drum. When it is determined that there is at least one photosensitive drum that performs low-coverage image forming operation or small-paper image forming operation for a long time in the image forming device, the secondary transfer voltage of the secondary transfer roller is adjusted to reduce the secondary transfer failure caused by any photosensitive drum that performs low-coverage image forming operation or small-paper image forming operation for a long time as much as possible, improve the secondary transfer effect, and then improve the image quality.

[0113] It should be noted that other contents involved in the embodiments of the present application can be found in the above Figures 2 to 5 For the sake of brevity, the description in the illustrated embodiment will not be repeated here.

[0114] Corresponding to the above embodiment, the embodiment of the present application further provides an image forming device.

[0115] See also Figure 8 , is a schematic diagram of the structure of another image forming device provided in an embodiment of the present application. Figure 8 As shown, the image forming apparatus 800 includes: a controller 801. The controller 801 is configured to execute the method embodiment described above, which will not be described in detail for the sake of brevity.

[0116] Corresponding to the above embodiment, the embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium may store a program, wherein when the program is running, the device where the computer-readable storage medium is located may be controlled to execute some or all of the steps in the above method embodiment. In a specific implementation, the computer-readable storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM).

[0117] Corresponding to the above-mentioned embodiment, the embodiment of the present application further provides a computer program product, which includes executable instructions. When the executable instructions are executed on a computer, the computer executes some or all of the steps in the above-mentioned method embodiment.

[0118] In the embodiments of the present application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0119] Those of ordinary skill in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented in a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0120] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0121] In several embodiments provided in the present application, if any function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0122] The above is only a specific implementation of the present application. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. The protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for controlling an image forming device, characterized in that: include: Acquire a historical coverage rate of the photosensitive drum, wherein the historical coverage rate is the average number of ink dots of an image forming operation corresponding to each page of the image forming job in the completed image forming job; If the historical coverage rate and the historical coverage rate threshold value satisfy a preset relationship, adjusting the transfer voltage of the secondary transfer roller from the first transfer voltage to the second transfer voltage; The secondary transfer roller is used to transfer the toner image on the intermediate transfer unit to the recording sheet.

2. The method according to claim 1, characterized in that The number of the photosensitive drums is multiple; The obtaining of the historical coverage of the photosensitive drum comprises: obtaining the historical coverage of each of the plurality of photosensitive drums; If the historical coverage rate and the historical coverage rate threshold satisfy a preset relationship, the transfer voltage of the secondary transfer roller is adjusted from the first transfer voltage to the second transfer voltage, including: if the historical coverage rate and the historical coverage rate threshold of any one of the photosensitive drums satisfy a preset relationship, the transfer voltage of the secondary transfer roller is adjusted from the first transfer voltage to the second transfer voltage.

3. The method according to claim 1, characterized in that The step of adjusting the transfer voltage of the secondary transfer roller from the first transfer voltage to the second transfer voltage comprises: According to the number of pages of the completed image forming job, the first transfer voltage of the secondary transfer roller is adjusted to obtain the second transfer voltage; adjusting the transfer voltage of the secondary transfer roller to the second transfer voltage; The number of pages of the completed image forming job is negatively correlated with the second transfer voltage.

4. The method according to claim 3, characterized in that The method of adjusting the first transfer voltage of the secondary transfer roller according to the number of pages of the completed image forming job to obtain the second transfer voltage includes: If the number of pages of the completed image forming job and the image forming job page number threshold satisfy a preset relationship, adjusting the first transfer voltage of the secondary transfer roller according to the number of pages of the completed image forming job to obtain a second transfer voltage; If the number of pages of the completed image forming job does not satisfy a preset relationship with the image forming job page number threshold, the first transfer voltage of the secondary transfer roller is adjusted according to the image forming job page number threshold to obtain a second transfer voltage.

5. The method according to claim 1, characterized in that The step of adjusting the transfer voltage of the secondary transfer roller from the first transfer voltage to the second transfer voltage comprises: adjusting a first transfer voltage of the secondary transfer roller to obtain a second transfer voltage; If the second transfer voltage satisfies a preset relationship with the transfer voltage threshold, adjusting the transfer voltage of the secondary transfer roller to the transfer voltage threshold; If the second transfer voltage and the transfer voltage threshold do not satisfy a preset relationship, the transfer voltage of the secondary transfer roller is adjusted to the second transfer voltage.

6. The method according to claim 1, characterized in that The toner image on the photosensitive drum is used to be transferred to the intermediate transfer unit, and the method further includes: The linear velocity of the photosensitive drum is controlled to be greater than or equal to the linear velocity of the developing roller and / or the linear velocity of the intermediate transfer unit.

7. The method according to claim 1, characterized in that The number of the photosensitive drums is plural, and the number of pages on which image forming jobs have been completed is an average value of the number of pages on which image forming jobs have been completed by the plural photosensitive drums.

8. An image forming device, characterized in that: include: A controller, wherein the controller is configured to execute the method according to any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

10. A computer program product, characterized in that The invention comprises a computer program, which, when executed by a processor, implements the method according to any one of claims 1 to 7.

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