Process cartridge

Abstract

The present application discloses a process cartridge. The process cartridge comprises a cartridge body, a developing roller and a resilient member; the cartridge body is provided with a powder compartment; the developing roller is rotatably arranged on the cartridge body and located at a powder outlet of the powder compartment; the resilient member is arranged on the cartridge body, and the resilient member is in contact with the developing roller and is used to limit the amount of toner powder carried by the developing roller and charge the toner powder carried by the developing roller; the arc length of the contact area between the developing roller and the resilient member is W, 1.5 mm ≤ W, and in the contact area between the developing roller and the resilient member, the horizontal component of the magnetic induction intensity of the surface of the developing roller in at least part of the contact area is larger than the vertical component. According to the present application, a thin toner powder layer having more uniform thickness and charge can be formed on the surface of the developing roller, so that when the thin toner powder layer reaches a developing position as the developing roller rotates, the toner powder involved in developing has higher charge, and can be more firmly adsorbed on paper during fixing and does not easily spread, thereby solving the problem of color blocks and rough edges on a printed image.

Description

Processing box

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on August 21, 2023, with application number 202311058664.9 and application name “Processing Box”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of image forming technology, and in particular to a processing box. Background Art

[0003] Laser printers are currently a common device used in offices and homes. The process cartridge is removably installed within the printer body and, driven by the printer, provides the printer with toner for forming images on paper. The process cartridge primarily comprises a photosensitive drum, a developing roller, a powder hopper housing, and a waste toner hopper housing. The photosensitive drum is installed within the waste toner hopper housing, while the developing roller is installed within the powder hopper housing, and the developing roller is magnetic. The powder hopper housing contains toner and has a long, strip-shaped powder outlet. A powder control scraper is also located within the powder hopper housing. Traditional powder control scrapers consist of a bracket and a blade. One end of the blade is fixed to the process cartridge housing via the bracket, while the other end of the blade contacts the surface of the developing roller.

[0004] When the existing processing cartridge is used in a laser printer, the image printed by the laser printer will have a problem of rough edges of color blocks. Especially in the late printing stage and in the low temperature in winter, the rough edge problem is more serious.

[0005] Application Contents

[0006] In order to overcome the problems existing in the above-mentioned prior art, the main purpose of the present application is to provide a processing box that can optimize the situation where color block burrs appear in images.

[0007] In order to achieve the above objectives, this application specifically adopts the following technical solutions:

[0008] The present application provides a process cartridge, comprising:

[0009] A box body, wherein the box body is provided with a powder bin;

[0010] a developing roller, the developing roller being rotatably disposed on the box body and located at the powder outlet of the powder bin;

[0011] an elastic member, the elastic member being provided on the box body and in contact with the developing roller, and being used for limiting the amount of toner carried by the developing roller and charging the toner carried by the developing roller;

[0012] The arc length of the contact area between the developing roller and the elastic member is W, 1.5 mm ≤ W, and in the contact area between the developing roller and the elastic member, the horizontal component of the magnetic induction intensity on the surface of the developing roller in at least part of the contact area is greater than the vertical component.

[0013] In some embodiments, the arc length W of the contact area between the developing roller and the elastic member is: 1.5 mm ≤ W ≤ W AB ;

[0014] Among them, W AB In order to ensure that the carbon powder in the powder bin is adsorbed to the surface of the developing roller and the thin layer of carbon powder passing through the elastic member can smoothly participate in the development, the elastic member can cover the arc length corresponding to the maximum area of ​​the developing roller from the powder outlet to the developing position without affecting the carbon powder in the powder bin to be adsorbed to the surface of the developing roller and the thin layer of carbon powder passing through the elastic member to smoothly participate in the development.

[0015] In some embodiments, an arc length W of a contact area between the developing roller and the elastic member is greater than or equal to 3 mm.

[0016] In some embodiments, in the contact area between the developing roller and the elastic member, along the circumference of the developing roller, a horizontal component of the magnetic induction intensity of the developing roller surface within an arc length of at least 1.5 mm is greater than a vertical component.

[0017] In some embodiments, in the contact area between the developing roller and the elastic member, along the circumference of the developing roller, a horizontal component of the magnetic induction intensity of the developing roller surface within an area of ​​at least 3 mm arc length is greater than a vertical component.

[0018] In some embodiments, the contact area between the developing roller and the elastic member includes a plurality of first sub-contact areas, and in each of the first sub-contact areas, the horizontal component of the magnetic induction intensity on the surface of the developing roller is greater than the vertical component.

[0019] In some embodiments, the contact area between the developing roller and the elastic member includes a second sub-contact area, and in the second sub-contact area, the horizontal component of the magnetic induction intensity on the surface of the developing roller is greater than the vertical component.

[0020] In some embodiments, the developing roller includes a magnetic core and an aluminum tube, the magnetic core is disposed on the box body, the aluminum tube is rotatably sleeved on the magnetic core, and the surface of the aluminum tube is in contact with the elastic member.

[0021] In some embodiments, the magnetic core is configured as a two-pole magnetic core, a three-pole magnetic core, or a four-pole magnetic core.

[0022] In some embodiments, the magnetic core is configured as a three-pole magnetic core.

[0023] In some embodiments, the processing box also includes a sealing structure, which is connected to the side wall of the powder bin and is located on one side of the powder outlet, and the elastic member is located on the other side of the powder outlet, one side of the developing roller abuts against the sealing structure, and the other side of the developing roller abuts against the elastic member.

[0024] In some embodiments, the elastic member extends along the axial direction of the developing roller, and in the axial direction of the developing roller, the length of the elastic member is greater than or equal to the length of the powder outlet.

[0025] In some embodiments, the processing box further includes a mounting boss, the mounting boss is provided on a side wall of the powder bin, and the elastic member is mounted on the mounting boss.

[0026] In some embodiments, the mounting boss extends along the axial direction of the developing roller.

[0027] In some embodiments, the mounting boss is provided with a mounting surface, the angle between the mounting surface and the side wall of the powder bin is θ, 0<θ≤90°, and the elastic member is mounted on the mounting surface.

[0028] In some embodiments, the surface of the elastic member in contact with the developing roller is an arc surface or a plane surface.

[0029] In some embodiments, a width of a surface of the elastic member in contact with the developing roller is greater than or equal to a width of a contact area of ​​the elastic member and the developing roller along a circumferential direction of the developing roller.

[0030] In some embodiments, the elastic member is configured as a sponge member.

[0031] In some embodiments, the sponge member is configured as a closed-cell sponge, or

[0032] A thin film is provided on the surface of the sponge member that contacts the developing roller.

[0033] In some embodiments, the elastic member is made of silicone or polyurethane.

[0034] Compared with the prior art, the contact area between the developing roller and the elastic member of the present application is larger, and in the contact area between the developing roller and the elastic member, the horizontal component of the magnetic induction intensity of the developing roller surface in at least part of the contact area is greater than the vertical component, so that the magnetic carbon powder adsorbed on the surface of the developing roller is rubbed by the developing roller surface and the elastic member over a longer distance in the direction of rotation of the developing roller. The friction is sufficient, so that the upper and lower layers of carbon powder adsorbed on the surface of the developing roller are fully exchanged, and finally a carbon powder thin layer with more uniform thickness and charge is formed on the surface of the developing roller. Then, when the carbon powder thin layer reaches the developing position as the developing roller rotates, the charge of the carbon powder participating in the development is higher, and it can be more firmly adsorbed on the paper during fixing and is not easy to spread, thereby optimizing the situation of color block burrs appearing in the printed image. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG1 is a partial internal structure diagram of a processing box provided by the prior art.

[0036] FIG2 is a partial internal structure diagram of the processing box provided in an embodiment of the present application.

[0037] FIG3 is a partial internal structure diagram of a processing box provided in another embodiment of the present application.

[0038] FIG4 is a partial internal structure diagram of a processing box provided in another embodiment of the present application.

[0039] FIG5 is a test diagram of the magnetic induction intensity on the surface of the developing roller provided in an embodiment of the present application.

[0040] FIG6 is a diagram showing the magnetic induction intensity distribution on the surface of the developing roller of the quadrupole magnetic core provided in an embodiment of the present application.

[0041] FIG. 7 is a diagram showing the magnetic induction intensity distribution on the surface of the developing roller of the three-pole magnetic core provided in an embodiment of the present application.

[0042] FIG8 is a diagram showing the distribution of magnetic induction intensity on the surface of the developing roller of the two-pole magnetic core provided in an embodiment of the present application.

[0043] Figure ID:

[0044] 1. Powder hopper; 11. Side wall; 12. Powder outlet; 2. Elastic member; 3. Developing roller; 31. Magnetic core; 32. Aluminum tube; 4. Sealing structure; 5. Mounting boss; 51. Mounting surface; 100. Processing box; 101. Photosensitive drum; 102. Developing roller; 103. Powder control assembly; 104. Toner; 105. Charging roller; 106. Transfer roller; 107. Laser source; 200. Paper. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0046] In the description of this application, unless otherwise expressly specified or limited, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance; unless otherwise specified or explained, the term "plurality" refers to two or more, and the term "multiple" refers to two or more; the terms "connected" and "fixed" should be understood in a broad sense. For example, "connected" can mean a fixed connection, a detachable connection, an integral connection, or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0047] In the description of this specification, it should be understood that the directional words such as "upper" and "lower" described in the embodiments of the present application are described from the perspectives shown in the accompanying drawings and should not be understood as limiting the embodiments of the present application. In addition, in the context, it should be understood that when it is mentioned that an element is connected to another element "on" or "under", it can not only be directly connected to the other element "on" or "under", but also indirectly connected to the other element "on" or "under" through an intermediate element.

[0048] In this application, the waste powder rate refers to the percentage of the total amount of waste powder generated at the end of the toner cartridge's life to the total amount of toner consumed; the transfer rate is one of the indicators to measure the effective utilization of toner, and the transfer rate = 1-waste powder rate.

[0049] Referring to Figure 1, Figure 1 is a partial internal structure diagram of a processing box provided by the prior art. A conventional processing box 100 using a magnetic system generally includes a box body, a photosensitive drum 101, a magnetic developing roller 102, and a powder control assembly 103. The box body is provided with a powder bin, in which magnetic toner 104 is stored. The developing roller 102, the photosensitive drum 101, and the powder control assembly 103 are all arranged in the box body, and the blade of the powder control assembly 103 is set as a PU blade. Among them, the developing roller 102 includes a magnetic core (not shown) and an aluminum tube (not shown). The magnetic core is arranged in the box body, and the aluminum tube is rotatably mounted on the magnetic core. During operation, the magnetic core does not move, and the aluminum tube can rotate around the magnetic core. Furthermore, the cross-section of the magnetic core is set to be cylindrical, and the magnetic core is uniformly magnetized to form multiple magnetic poles, generally four magnetic poles (S1, S2, N1, N2).

[0050] When the processing box is in working state, the toner 104, the aluminum tube of the developing roller 102 and the photosensitive drum 101 are all charged with the same charge (positive or negative). For example, the toner 104, the aluminum tube of the developing roller 102 and the photosensitive drum 101 are all charged negatively. The magnetic toner 104 supplied from the powder bin is charged by the friction of the aluminum tube and the PU knife on the surface of the aluminum tube of the developing roller 102 to form a thin layer of toner. The thin layer of toner will rotate with the aluminum tube, and the thin layer of toner is not completely stationary relative to the surface of the aluminum tube of the developing roller 102. Instead, part of the toner 104 is excited to jump, forming a layer of "toner cloud" structure around the aluminum tube of the developing roller 102.

[0051] The toner cloud forms as follows: Toner 104 is magnetically bound to the aluminum tube surface of developing roller 102 by the magnetic force of the developing roller's core. Simultaneously, toner 104 is also affected by the negative electric field of the developing roller's tube. The direction of the magnetic force on toner 104 is opposite to the direction of the electric force from developing roller 102. On the side of developing roller 102 facing photosensitive drum 101, the magnetic force on toner 104 is constant, but the electric force varies with the charging voltage of developing roller 102. The charge of the developing roller 102 continuously fluctuates within a certain range. When the charging voltage of the developing roller 102 is high, the electric field force on the toner 104 is greater than the magnetic force, and the toner 104 will break away from the developing roller 102 and fly out. When the charging voltage of the developing roller 102 is low, the electric field force on the toner 104 is less than the magnetic force, and the toner 104 is bound by the magnetic force and returns to the surface of the aluminum tube of the developing roller 102. Since the voltage of the developing roller 102 fluctuates rapidly, the toner 104 jumps rapidly, thereby forming a toner cloud around the aluminum tube of the developing roller 102.

[0052] On the photosensitive drum 101 side, the charging roller 105 uniformly charges the insulator drum surface of the photosensitive drum 101, making the drum surface of the photosensitive drum 101 uniformly negatively charged. When the optical semiconductor material on the drum surface is irradiated by laser light from the laser source 107, it instantly becomes conductive, loses its static electricity, and restores its insulation, forming a low-potential latent image. When the toner cloud approaches the drum surface of the photosensitive drum 101, the potential of the latent image portion is low, and the high-potential toner 104 forms electrostatic attraction with the low-potential drum surface of the photosensitive drum 101, producing a visible image (development process). The drum surface of the photosensitive drum 101 that is not irradiated by the laser has a high potential, which repels the charge of the high-potential toner 104 with the same charge. The toner 104 does not adhere to the charged drum surface and continues to participate in the toner 104 jumping. The visible image formed on the surface of the photosensitive drum 101 then rotates along the drum toward the paper 200 (direction A is the paper's transport direction). At this point, the negatively charged toner 104 is attracted by the positively charged transfer roller 106 inside the printer and transferred to the surface of the paper 200. Afterward, the toner is heated and pressurized by the printer's fixing device, where it penetrates the fibers of the paper 200 and solidifies onto the paper 200. After the visible image on the photosensitive drum 101 is transferred, any remaining toner 104 adhering to the surface of the drum 101 is scraped off by the cleaning device of the process cartridge 100 and removed to the waste toner bin.

[0053] However, in the prior art, when a laser printer uses the above-mentioned processing box 100 for printing, the printed image will have the problem of color blocks and rough edges. This problem is particularly serious in the later stages of printing and in low temperatures in winter. This is mainly because when the traditional PU blade charges the magnetic toner 104, the toner layer is subjected to friction from two completely different materials, the blade and the aluminum tube surface of the developing roller 102. The charge of the toner layer is necessarily stratified. The lower layer of toner 104 in contact with the aluminum tube surface has a high charge, while the upper layer of toner 104 in contact with the PU blade has a low charge. In addition, the contact area between the PU blade and the aluminum tube surface of the developing roller 102 is very small and can be regarded as linear contact. During the powder control and friction process, the upper and lower toner layers do not exchange sufficiently, and the charge stratification cannot be significantly improved. Furthermore, the low-charge toner 104 in the upper layer is strongly attracted by the magnetic field of the magnetic core of the developing roller 102, which also exerts pressure on the high-charge toner 104 in the lower layer, preventing it from jumping. As a result, when the photosensitive drum 101 is developing, the toner 104 with a low charge on the upper layer often jumps to the surface of the photosensitive drum 101 to participate in the development. Since the toner 104 participating in the development has a low charge, it cannot be firmly adsorbed to the paper during the subsequent fixing process, causing the toner 104 to spread, resulting in print quality issues such as rough edges in the color blocks.

[0054] Especially in winter or when the weather is dry, the lower layer of magnetic carbon powder 104 is more likely to carry too high a charge. After the magnetic carbon powder 104 rubs against the aluminum tube, the two remain motionless during the subsequent rotation. Therefore, the electrostatic adsorption force generated by the two will always exist. In winter, the static electricity generated by the magnetic carbon powder 104 and the surface of the aluminum tube may reach thousands or tens of thousands of volts, which is much larger than the external electric field on the surface of the aluminum tube (generally the instantaneous peak is about 1400V). Therefore, the lower layer of magnetic carbon powder 104 with a high charge on the surface of the aluminum tube is basically impossible to jump onto the photosensitive drum 101.

[0055] Referring to Figure 2, Figure 2 is a partial internal structure diagram of the processing box provided in an embodiment of the present application. The embodiment of the present application discloses a processing box, which includes a box body, a developing roller 3 and an elastic member 2. The box body is provided with a powder bin 1, and the powder bin 1 is provided with a powder outlet 12. The developing roller 3 is rotatably arranged in the box body and is located at the powder outlet 12 of the powder bin 1. The elastic member 2 is provided in the box body, and the elastic member 2 is in contact with the developing roller 3, and is used to limit the amount of carbon powder carried by the developing roller 3 and to charge the carbon powder carried by the developing roller 3, that is, the function of the powder control scraper is realized by the elastic member 2. Wherein, the arc length of the contact area between the developing roller 3 and the elastic member 2 is W, 1.5mm≤W≤W AB , and in the contact area between the developing roller 3 and the elastic member 2, the horizontal component of the magnetic induction intensity on the surface of the developing roller 3 in at least part of the contact area is greater than the vertical component, W AB To ensure that the toner in the powder hopper 1 is not affected by adsorption to the surface of the developing roller 3 and that the thin layer of toner passing through the elastic member 2 can smoothly participate in the development process, the arc length corresponding to the maximum area of ​​the developing roller 3 that the elastic member 2 can cover between the powder outlet 12 and the developing position is sufficient. That is, in this embodiment, the arc length of the elastic member 2 covering the aluminum tube surface of the developing roller 3 is greater than the arc length of a conventional PU blade covering the aluminum tube surface of the developing roller 3. Moreover, in at least a portion of the contact area between the elastic member 2 and the aluminum tube surface of the developing roller 3, the horizontal component of the magnetic induction intensity on the surface of the developing roller 3 is greater than the vertical component.

[0056] Specifically, the developing roller 3 includes a magnetic core 31 and an aluminum tube 32. The magnetic core 31 is disposed in the box body, and the aluminum tube 32 is rotatably sleeved on the magnetic core 31, with the surface of the aluminum tube 32 abutting against the elastic member 2. In this embodiment, the magnetic core 31 is configured as a three-pole magnetic core (including one S pole and two N poles or one N pole and two S poles). It is understood that in other embodiments, the magnetic core 31 can also be configured as a four-pole magnetic core or a two-pole magnetic core.

[0057] In this embodiment, the contact area between the developing roller 3 and the elastic member 2 is larger, and in the contact area between the developing roller 3 and the elastic member 2, the horizontal component of the magnetic induction intensity on the surface of the developing roller 3 in at least part of the contact area is greater than the vertical component, so that the magnetic carbon powder adsorbed on the surface of the developing roller 3 is rubbed by the surface of the developing roller 3 and the elastic member 2 over a longer distance in the rotation direction of the developing roller 3. The friction is sufficient, so that the upper and lower layers of carbon powder are fully exchanged, and finally a carbon powder thin layer with more uniform thickness and charge is formed on the surface of the developing roller 3. Then, when the carbon powder thin layer reaches the developing position as the developing roller 3 rotates, the charge of the carbon powder participating in the development is higher, and it can be more firmly adsorbed on the paper during fixing and is not easy to spread, thereby optimizing the problem of burrs.

[0058] In some embodiments, the arc length W of the contact area between the developing roller 3 and the elastic member 2 is greater than or equal to 2 mm. Specifically, the arc length W of the contact area between the developing roller 3 and the elastic member 2 can be 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, etc.; and in the contact area between the developing roller 3 and the elastic member 2, along the circumference of the developing roller 3, the horizontal component of the magnetic induction intensity on the surface of the developing roller 3 in at least an arc length area of ​​2 mm is greater than the vertical component. In order to balance the cost, in the contact area between the developing roller 3 and the elastic member 2, along the circumference of the developing roller 3, preferably within a 3 mm arc length area, the horizontal component of the magnetic induction intensity on the surface of the developing roller 3 is greater than the vertical component.

[0059] In some embodiments, the contact area between the developing roller 3 and the elastic member 2 includes a plurality of first sub-contact areas, wherein the horizontal component of the magnetic induction intensity on the surface of the aluminum tube 32 of the developing roller 3 in each first sub-contact area is greater than the vertical component, and the sum of the arc lengths W1 of all the first sub-contact areas satisfies: 1.5 mm ≤ W1 ≤ W AB Alternatively, the contact area between the developing roller 3 and the elastic member 2 includes a second sub-contact area, in which the horizontal component of the magnetic induction intensity on the surface of the aluminum tube 32 of the developing roller 3 is greater than the vertical component, and the arc length W2 of the second sub-contact area satisfies: 1.5mm≤W2≤W AB .

[0060] Continuing with Figure 2, the contact area between the elastic member 2 and the aluminum tube 32 of the developing roller 3 is A = L * W, where L is the length of the contact area between the elastic member 2 and the aluminum tube 32 along the axis of the developing roller 3, and W is the arc length of the contact area on the developing roller 3 surface between the upstream and downstream ends of the aluminum tube 32 in the rotational direction of the aluminum tube 32. Given that the arc length of the aluminum tube 32 of the developing roller 3 is difficult to measure, a process cartridge can be placed in a printer, printed a certain amount of work, then removed and disassembled. A rectangular print mark will be formed on the contact surface between the elastic member 2 and the developing roller 3. This rectangular print mark has a length of L and a width of W. If a process cartridge using a conventional PU blade is used, the contact area between the PU blade and the developing roller 3 surface can also be determined using the same method. For a developing roller 3 with a diameter of 12 mm, for example, the contact area between the PU blade and the developing roller 3 surface is approximately a straight line, approximately 1 mm wide. (Since the mark is formed by toner and has smudged edges, the width of the entire print mark will be uneven, so the average value is used, with a reasonable error range of plus or minus 0.3 mm.) In order to improve the problem of color block burrs appearing in images printed by a processing box using a traditional PU knife, in the present application, an elastic part 2 is used to replace the traditional PU knife, so that the arc length W of the elastic part 2 covering the aluminum tube 32 is greater than or equal to 1.5 mm, thereby increasing the distance in which the carbon powder layer is rubbed between the aluminum tube 32 and the elastic part 2 in the rotation direction of the aluminum tube 32, so that the upper and lower layers of carbon powder adsorbed on the surface of the developing roller 3 are fully exchanged, and finally a carbon powder layer with more uniform thickness and charge is formed on the surface of the aluminum tube 32.

[0061] In some embodiments, the developer roller 3 can also have other diameters, such as 16 mm and 20 mm. As the diameter of the developer roller 3 increases, the arc length W of the contact area between the elastic member 2 and the aluminum tube 32 also increases. Furthermore, to further enhance the performance compared to conventional PU blades, for a developer roller 3 with a diameter of 12 mm, the arc length W of the elastic member 2 covering the aluminum tube 32 of the developer roller 3 can also be greater than or equal to 3 mm. To balance costs, the arc length of the elastic member 2 covering the aluminum tube 32 is preferably 3 mm.

[0062] Currently, a multi-pole magnetic core 31 is typically obtained by magnetizing the magnetic core 31. Due to the different magnetic poles of the magnetic core 31, the distribution of magnetic flux density on the surface of the aluminum tube 32 also varies. Some areas of the aluminum tube 32 have a stronger horizontal component of magnetic flux density, while others have a stronger vertical component. Charges in a magnetic field are affected by magnetic forces. In areas with a stronger vertical component, the thin layer of charged carbon powder on the surface of the aluminum tube 32 is more firmly adsorbed on the surface of the aluminum tube 32, hindering the exchange of carbon powder layers between the upper and lower layers. Therefore, in the present application, within the area where the elastic member 2 covers the surface of the aluminum tube 32, at least in some areas, the horizontal component of the magnetic flux density on the surface of the aluminum tube 32 is greater than the vertical component.

[0063] Furthermore, the process cartridge also includes a sealing structure 4 and a mounting boss 5. The sealing structure 4 is connected to the side wall 11 of the powder hopper 1 and is located on one side of the powder outlet 12. The mounting boss 5 is provided on the side wall 11 of the powder hopper 1 and is located on the other side of the powder outlet 12. The mounting boss 5 extends axially along the developing roller 3 and has a mounting surface 51. The angle between the mounting surface 51 and the side wall 11 of the powder hopper 1 is θ (shown in FIG. 3 ), where 0 < θ ≤ 90°. An elastic member 2 is mounted on the mounting surface 51 of the mounting boss 5 and extends axially along the developing roller 3. In the axial direction of the developing roller 3, the length of the elastic member 2 is greater than or equal to the length of the powder outlet 12, that is, the elastic member 2 covers the entire length of the powder outlet 12 along the axial direction of the developing roller 3. One side of the developing roller 3 abuts the sealing structure 4, and the other side of the developing roller 3 abuts the elastic member 2.

[0064] In some embodiments, the surface where the elastic member 2 contacts the developing roller 3 is a plane. In this case, the cross-section of the elastic member 2 can be set to a rectangle, a triangle, etc.; or, the surface where the elastic member 2 contacts the developing roller 3 is set to an arc surface. In this case, the elastic member 2 can be set to an arc structure.

[0065] In some embodiments, to prevent the elastic member 2 from curling during use, the width of the elastic member 2 can be increased so that the width of the surface of the elastic member 2 in contact with the developing roller 3 is greater than or equal to the circumferential width of the contact area between the elastic member 2 and the developing roller 3. This allows the elastic member 2 to have a surplus width beyond the contact width with the developing roller 3. For example, the overall width of the sponge member can be set to 8 mm, with the central portion of the sponge member in contact with the developing roller surface having a width of 3 mm.

[0066] Due to the different characteristics of different elastic materials, such as different rebound times, the thickness of the elastic part 2 and the pressure of the elastic part 2 in contact with the surface of the developing roller 3 (which can also be measured by torque) can be adjusted to ensure that the arc length of the elastic part 2 covering the surface of the aluminum tube 32 is greater than the arc length of the traditional PU knife covering the surface of the developing roller 3.

[0067] In this embodiment, the elastic member 2 is configured as a sponge. Preferably, the sponge is configured as a closed-pore sponge with a relatively flat surface. It is understood that in other embodiments, the surface of the sponge that contacts the developing roller 3 may be provided with a thin film. This is because ordinary sponges have small pores on their surface. To prevent residual powder from affecting the quality of the sponge, a thin film may be applied to the surface of the sponge that contacts the aluminum tube 32, thereby forming a relatively flat contact surface. Alternatively, the elastic member 2 may be made of silicone or polyurethane. Continuing with FIG2 , due to the physical properties of the sponge, when the sponge contacts the surface of the aluminum tube 32 of the developing roller 3 (direction B in the figure is the rotation direction of the aluminum tube 32), a certain degree of bending deformation occurs, allowing the sponge to cover a larger area of ​​the surface of the aluminum tube 32.

[0068] In this embodiment, the mounting surface 51 of the mounting boss 5 is a plane perpendicular to the side wall 11 of the powder bin 1.

[0069] That is, the angle θ between the mounting surface 51 of the mounting boss 5 and the side wall of the powder hopper 1 is 90°, as shown in FIG2 ; in other embodiments, the mounting surface 51 of the mounting boss 5 can also be set as an inclined surface, that is, the angle θ between the mounting surface 51 of the mounting boss 5 and the side wall of the powder hopper 1 is an acute angle, as shown in FIG3 . Theoretically, without affecting the carbon powder in the powder hopper 1 adsorbed to the surface of the aluminum tube 32 of the developing roller 3 and the thin layer of carbon powder passing through the sponge member can smoothly participate in the development, the sponge member can cover most of the area of ​​the developing roller 3 between the powder outlet 12 of the powder hopper 1 and the developing position S. However, due to the constraints of the available installation space inside the processing box, the rectangular sponge member cannot cover such a large area. Therefore, as shown in FIG4 , the sponge member is set as a curved surface structure to meet the demand for a larger coverage area of ​​the developing roller 3. Specifically, according to the actual product requirements, the area on the mounting surface 51 of the mounting boss 5 for mounting the sponge part, the angle between the mounting surface 51 and the side wall 11 of the powder hopper 1, and the distance from the sponge part to the axis core of the developing roller 3 can be selected to achieve the expected area of ​​the sponge part covering the surface of the developing roller 3 between the powder outlet 12 of the powder hopper 1 and the developing position.

[0070] In some embodiments, to ensure sealing, sealing felt is provided at both ends of the powder outlet 12. The ends of the elastic member 2 can be tightly connected to the sealing felt to achieve a seal at both ends of the powder outlet 12 and prevent powder leakage. Alternatively, if the elastic member 2 is a sponge, the ends of the sponge can be appropriately extended, so that the elongated sponge can replace not only the traditional powder control knife but also the sealing felt structure at both ends of the powder control blade.

[0071] When detecting the magnetic induction intensity on the surface of the aluminum tube 32 of the developing roller 3, taking a traditional four-pole magnetic core as an example, it has two S poles and two N poles, namely, S1 pole, S2 pole, N1 pole and N2 pole. At S1, S2, N1 and N2, the vertical component of the magnetic induction intensity is the largest, and the horizontal component of the magnetic induction intensity between the S pole and the N pole is greater than the vertical component. The S1 pole is the main pole, facing the photosensitive drum, and the S2 pole is near the powder outlet 12. The distribution of the magnetic induction intensity (also known as magnetic flux density or flux density) on the surface of the aluminum tube 32 can be measured by a Gaussmeter with a probe. Generally, the Gaussmeter has a rod-shaped axial probe connected to the main component of the Gaussmeter. During the specific measurement, the aluminum tube 32 is fixed in a horizontal position and the magnetic core 31 can be rotated. The aluminum tube 32 and the magnetic core 31 are concentric, and the gap between the magnetic core 31 and the aluminum tube 32 is a constant regardless of the peripheral position on the magnetic core 31. Therefore, by rotating the magnetic core 31 while maintaining the relative position of the probe and the aluminum tube 32 unchanged, the magnetic flux density at all circumferential positions of the aluminum tube 32 can be measured. Furthermore, a gauss meter is required to measure the horizontal and vertical components of the magnetic flux density at all circumferential positions of the aluminum tube 32.

[0072] As shown in FIG5 , for example, the horizontal and vertical components of the magnetic flux density on the surface of the aluminum tube 32 can be measured using a YDX-14AB magnetic tester from Zhuhai Yida Automation Equipment Co., Ltd. A rod-shaped probe is fixed horizontally approximately 2.5 mm above the surface of the aluminum tube 32, so that the center of the probe's detection point E is aligned with the center of the surface of the aluminum tube 32 (as shown in position F1 in FIG5 ). While maintaining the relative position of the probe's detection point E and the surface of the aluminum tube 32 unchanged, the magnetic core 31 is gradually rotated by a fixed angle until it completes one rotation, for example, by 5° each rotation. The vertical component of the magnetic flux density at various angles along the circumference of the aluminum tube 32 (i.e., the magnetic flux density in the direction normal to the surface of the aluminum tube 32) is measured. The rotation angle of the magnetic core 31 is recorded in correspondence with the vertical component of the magnetic flux density detected by the probe. After measuring the vertical component of one rotation (i.e., the magnetic core 31 has returned to the 0-degree position), the rod-shaped probe is kept fixed horizontally and adjusted to the center of the aluminum tube 32, contacting the surface of the aluminum tube 32 (as shown in position F2 in FIG5 ). Because the probe's detection point E is 2.5 mm from the edge of aluminum tube 32, the probe detects the horizontal component of the magnetic flux density approximately 2.5 mm from the surface of aluminum tube 32 (i.e., the magnetic flux density value in the tangential direction of the surface of aluminum tube 32). Similarly, the magnetic core 31 is gradually rotated by a fixed angle until it completes one rotation. The rotation angle of the magnetic core 31 is recorded in correspondence with the horizontal component of the magnetic flux density detected by the probe. Finally, the measured horizontal and vertical components of the magnetic flux density are aligned to a coordinate system, resulting in the magnetic flux density distribution diagrams shown in Figures 6 to 8.

[0073] Alternatively, the horizontal and vertical components of magnetic induction intensity can be measured using a Bell 9900 series Gaussmeter with a rod-shaped probe, A-99-153. During measurement, the aluminum tube 32 is fixed in a horizontal position, and the magnetic core 31 is rotatably supported. When the Gaussmeter probe is oriented normal to the surface of the aluminum tube 32, the vertical component is measured. Simply rotate the probe 90° toward a tangent to the surface of the aluminum tube 32 to measure the horizontal component at the same position.

[0074] Using a YDX-14AB magnetic tester, the above method was used to measure the magnetic flux density distribution of the four-pole magnetic core and the aluminum tube 32 of the developing roller 3 with a diameter of 12 mm, as shown in Figure 6. In the figure, the solid line is the vertical component of the magnetic flux density, and the dotted line is the horizontal component of the magnetic flux density. As can be seen from Figure 6, there are two areas in the AB region where the horizontal component of the magnetic flux density is greater than the vertical component (i.e., the area surrounded by the straight lines C1 and D1 and the area surrounded by the straight lines C2 and D2 in Figure 6). For the four-pole magnetic core, from the perspective of structural simplicity and cost savings, it is preferred that the elastic member 2 is arranged near the powder outlet 12, and of the arc length W of the elastic member 2 covering the surface of the aluminum tube 32 of the developing roller 3, at least 1.5 mm of the arc length is located in the area surrounded by the straight lines C2 and D2.

[0075] In some embodiments, the magnetic flux density distribution on the surface of the aluminum tube 32 of the developing roller 3 (S1 being the main pole) of the three-pole magnetic core (S1, N1, N2) was measured using the same equipment, as shown in FIG7 (note that since the magnetic flux density measured is on the surface of the aluminum tube 32, the peak values ​​of the vertical components corresponding to N1 and N2 are displayed as the same, equivalent to N in FIG7 ). Similarly, the arc length W of the elastic member 2 covering the surface of the aluminum tube 32 of the developing roller 3 must satisfy the following relationship: 1.5 mm ≤ W ≤ W AB , and the horizontal component of the magnetic induction intensity on the surface of the aluminum tube 32 in at least part of the area within the arc length W is greater than the vertical component (such as the area enclosed by the straight line C and the straight line D in Figure 7). Preferably, the horizontal component of the magnetic induction intensity on the surface of the aluminum tube 32 in at least a 1.5mm area within the arc length W is greater than the vertical component (such as the area directly enclosed by C1 and D1 in the area enclosed by the straight line C and D in Figure 7). In addition, the three-pole magnetic core can also use one N pole and two S poles (i.e., N1, S1, S2), in which case N is the main pole. In some embodiments, the magnetic induction intensity distribution on the surface of the aluminum tube 32 of the developing roller 3 (S1 is the main pole) of the two-pole magnetic core (S1, N1) is measured using the same equipment as shown in Figure 8. Similarly, the arc length W of the elastic member 2 covering the surface of the aluminum tube 32 of the developing roller 3 needs to satisfy the relationship: 1.5mm≤W≤W AB, and the horizontal component of the magnetic flux density on the surface of the aluminum tube 32 in at least a portion of the arc length W is greater than the vertical component (such as the area enclosed by lines C and D in FIG8 ). Preferably, the horizontal component of the magnetic flux density on the surface of the aluminum tube 32 in at least a 1.5 mm area of ​​the arc length W is greater than the vertical component.

[0076] By comparing the elastic member 2 with a quadrupole core, a tripolar core, and a secondary core, this application found that when using a tripolar core, the area where the horizontal component of the magnetic flux density on the surface of the aluminum tube 32 exceeds the vertical component in the region corresponding to AB is larger, the curve is smoother, and the horizontal component value is larger. Therefore, when the elastic member 2 is the same, it is preferred to use a tripolar core. In addition, because the area where the horizontal component of the magnetic flux density on the surface of the aluminum tube 32 exceeds the vertical component in the region corresponding to AB is the largest with a tripolar core, the matching design requirements for the mounting boss 5 and the elastic member 2 are lower.

[0077] Compared to the approximately linear contact between the conventional PU blade and the surface of the developing roller 3, the elastic member 2 of the present application has a larger contact area with the surface of the developing roller 3. Furthermore, in at least a portion of the covered area on the surface of the aluminum tube 32, the horizontal component of the magnetic induction intensity of the magnetic core 31 is greater than the vertical component. Thus, the magnetic toner adsorbed on the surface of the developing roller 3 is rubbed by both the surface of the aluminum tube 32 and the elastic member 2 over a relatively long distance in the direction of rotation of the developing roller 3. The friction is sufficient, and in at least a portion of this distance, the horizontal component of the induction intensity on the surface of the aluminum tube 32 is greater than the vertical component. The upper and lower layers of toner adsorbed on the surface of the developing roller are fully exchanged, ultimately forming a thin layer of toner with a more uniform thickness and charge on the surface of the developing roller 3. When the thin layer of toner reaches the developing position directly opposite the photosensitive drum (OPC) as the developing roller 3 rotates, the toner participating in the OPC development has a higher charge, allowing it to be more firmly adsorbed on the paper during fixing and less likely to spread, thereby optimizing the problem of burrs.

[0078] In addition, since the thin layer of toner reaching the developing position has a high and uniform charge, less toner is needed to fill the voltage of the OPC electrostatic latent image. While reducing the toner consumption, the transfer rate is improved, the waste toner rate is reduced, and the grayscale quality is better.

[0079] In some embodiments, a coating that can increase the charge of carbon powder and / or increase friction can be applied to the surface of the sponge to further enhance the burr optimization effect, increase the transfer rate, and reduce the waste powder rate.

[0080] Taking a rectangular sponge and a 12mm diameter developer roller 3 as an example, the sponge is a closed-cell sponge. The width of contact between the developer roller 3 surface and the sponge is 3mm (average value, i.e., the arc length W of the aluminum tube 32 covered is 3mm). Furthermore, the horizontal component of the magnetic flux density of the magnetic core 31 in the area of ​​the aluminum tube 32 covered by the sponge is greater than the vertical component. Comparative experiments revealed the print quality of process cartridges using three different combinations of magnetic cores and sponges, as shown in the table below.

[0081] Table 1 is a comparison table of the printing quality of the process cartridges with three types of magnetic cores and sponge parts.

[0082] Generally, traditional processing boxes use PU knives and the developing rollers use four-pole magnetic cores, which result in obvious burrs. When the processing box of the present application uses a four-pole magnetic core, the burrs are significantly improved compared to traditional processing boxes. In addition, when the processing box of the present application uses two-pole and three-pole magnetic cores, compared to traditional processing boxes, the waste powder rate is significantly lower and the transfer rate is improved while significantly improving the burrs. Among them, the sponge part is combined with the three-pole magnetic core to obtain the best printing quality.

[0083] The above description is merely a preferred embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A processing box, characterized in that: include: A box body, wherein the box body is provided with a powder bin; A developing roller, which is rotatably disposed on the box body and located at the powder outlet of the powder bin; an elastic member, the elastic member being arranged on the box body and in contact with the developing roller, and being used for limiting the amount of carbon powder carried by the developing roller and charging the carbon powder carried by the developing roller; The arc length of the contact area between the developing roller and the elastic member is W, 1.5 mm ≤ W, and in the contact area between the developing roller and the elastic member, the horizontal component of the magnetic induction intensity on the surface of the developing roller in at least part of the contact area is greater than the vertical component.

2. The process cartridge according to claim 1, wherein: The arc length W of the contact area between the developing roller and the elastic member is: 1.5 mm ≤ W ≤ W AB ; Among them, W AB In order to ensure that the toner in the powder bin is adsorbed to the surface of the developing roller without affecting the toner layer passing through the elastic member and can smoothly participate in the development, the elastic member can cover the arc length corresponding to the maximum area of ​​the developing roller from the powder outlet to the developing position.

3. The process cartridge according to claim 2, wherein: An arc length W of a contact area between the developing roller and the elastic member is greater than or equal to 3 mm.

4. The process cartridge according to claim 1, wherein: In the contact area between the developing roller and the elastic member, along the circumference of the developing roller, the horizontal component of the magnetic flux density on the surface of the developing roller in an area of ​​at least 1.5 mm arc length is greater than the vertical component.

5. The process cartridge according to claim 4, wherein: In the contact area between the developing roller and the elastic member, along the circumference of the developing roller, the horizontal component of the magnetic flux density on the surface of the developing roller in an area of ​​at least 3 mm arc length is greater than the vertical component.

6. The process cartridge according to claim 1, wherein: The contact area between the developing roller and the elastic member includes a plurality of first sub-contact areas, and the horizontal component of the magnetic induction intensity on the surface of the developing roller in each of the first sub-contact areas is greater than the vertical component.

7. The process cartridge according to claim 1, wherein: The contact area between the developing roller and the elastic member includes a second sub-contact area. In the second sub-contact area, the horizontal component of the magnetic induction intensity on the surface of the developing roller is greater than the vertical component.

8. The process cartridge according to any one of claims 1 to 7, characterized in that: The developing roller comprises a magnetic core and an aluminum tube, wherein the magnetic core is arranged on the box body, the aluminum tube is rotatably sleeved on the magnetic core, and the surface of the aluminum tube abuts against the elastic member.

9. The process cartridge according to claim 8, wherein: The magnetic core is configured as a two-pole magnetic core, a three-pole magnetic core or a four-pole magnetic core.

10. The process cartridge according to claim 8, wherein: The magnetic core is configured as a three-pole magnetic core.

11. The process cartridge according to claim 1, wherein: The processing box also includes a sealing structure, which is connected to the side wall of the powder bin and located on one side of the powder outlet, and the elastic member is located on the other side of the powder outlet, one side of the developing roller abuts against the sealing structure, and the other side of the developing roller abuts against the elastic member.

12. The process cartridge according to claim 1, wherein: The elastic member extends along the axial direction of the developing roller, and in the axial direction of the developing roller, the length of the elastic member is greater than or equal to the length of the powder outlet.

13. The process cartridge according to claim 12, wherein: The processing box further comprises a mounting boss, the mounting boss is arranged on the side wall of the powder bin, and the elastic member is mounted on the mounting boss.

14. The process cartridge according to claim 13, wherein: The mounting boss extends along the axial direction of the developing roller.

15. The process cartridge according to claim 13, wherein: The mounting boss is provided with a mounting surface, the included angle between the mounting surface and the side wall of the powder bin is θ, 0<θ≤90°, and the elastic member is mounted on the mounting surface.

16. The process cartridge according to claim 1, wherein: The surface of the elastic member contacting the developing roller is an arc surface or a plane surface.

17. The process cartridge according to claim 1, wherein: The width of the surface of the elastic member contacting the developing roller is greater than or equal to the width of the contact area of ​​the elastic member and the developing roller along the circumferential direction of the developing roller.

18. The process cartridge according to claim 1, wherein: The elastic member is configured as a sponge member.

19. The process cartridge according to claim 18, wherein: The sponge member is a closed-cell sponge, or A film is provided on the surface of the sponge member contacting the developing roller.

20. The process cartridge according to claim 1, wherein: The elastic member is made of silicone or polyurethane.

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