Fixing device and printer

Abstract

A fixing device includes a heating roller, a pressure roller, and a compensation roller. Wherein the heating roller is provided with a central axis in the length direction of the heating roller, and the heating roller can rotate around the central axis; the pressure roller is parallel to the heating roller, and the circumferential face of the pressure roller makes contact with the circumferential face of the heating roller so that pressure in the radial direction of the heating roller can be applied to the heating roller. The compensation roller is parallel to the heating roller, the circumferential face of the compensation roller makes contact with the circumferential face of the heating roller, and the compensation roller is used for applying compensation force in the radial direction of the heating roller to the heating roller so as to offset at least part of pressure. The flexural deflection generated by the heating roller under the action of pressure can be reduced, the service life of equipment is prolonged, and the image quality of a printed draft is improved. The invention further discloses a printer.

Description

Technical Field

[0001] This application relates to the field of printing apparatus technology, and particularly to a fixing device and a printer. Background Art

[0002] With the rapid development of economy and communication technology, printers, as terminal products, have broken through the traditional commercial office scenarios and entered consumers' home lives. Laser printers, as a high-tech product, have gained popularity among consumers and are widely used in many countries due to their fast printing speed, high quality, and cost-effectiveness. Laser printers are output devices that combine laser scanning technology and electronic imaging technology. During the imaging process of a laser printer, image processors such as the paper feeding mechanism, optical engine, and developing module transfer toner onto the recording material through a transfer method, and fix the unfixed image of the target image information onto the surface of the recording material as a permanent image.

[0003] Currently, laser printers tend to have a gradual decline in print quality after a period of use. When the print quality fails to meet consumer needs, the printer can no longer be used. Therefore, existing laser printers suffer from poor print quality stability and short lifespan. Summary of the Invention

[0004] This application provides a fixing device and a printer that can improve the stability of printed image quality and extend the lifespan of the printer.

[0005] In a first aspect, this application provides a fixing apparatus, including a heating roller, a pressure roller, and a compensating roller. The heating roller has a central axis along its length and is rotatable about the central axis. The pressure roller is parallel to the heating roller, and its circumferential surface contacts the circumferential surface of the heating roller to apply radial pressure to the heating roller. The compensating roller is parallel to the heating roller, and its circumferential surface contacts the circumferential surface of the heating roller. The compensating roller applies a radial compensating force to the heating roller to counteract at least a portion of the pressure.

[0006] This application, by setting a compensation roller, can apply a compensating force to the heating roller to counteract at least part of the pressure from the pressure roller, thereby reducing the amount of flexural deformation of the heating roller under pressure, improving the stability of the printed image quality and the service life of the printer.

[0007] This application does not specifically limit the number of compensating rollers. Any number of compensating rollers that can offset at least part of the pressure based on the above technical solutions are within the scope of protection of this application. In some implementations of this application, the number of compensating rollers is one, and the compensating roller and the pressure roller are arranged radially opposite to each other on both sides of the heating roller. The inventors have discovered that when the compensating roller contacts the heating roller, it disperses the heat of the heating roller. Therefore, by setting only one compensating roller, the heat loss of the heating roller can be reduced, and the heating efficiency of the heating roller can be improved. In other implementations of this application, the number of compensating rollers is at least two, and each compensating roller is arranged circumferentially around the heating roller. The plane where the axis of the heating roller and the axis of the pressure roller are located is the reference plane. When the number of compensating rollers is even, each compensating roller is mirror-symmetrically distributed on both sides of the reference plane. When the number of compensating rollers is odd, the axis of one compensating roller is located on the reference plane, and the remaining compensating rollers are mirror-symmetrically distributed on both sides of the reference plane. By setting multiple compensating rollers, the deformation at multiple positions of the heating roller can be compensated, improving the compensation effect. However, since setting up multiple compensation rollers takes up a lot of space and the compensation rollers will disperse a lot of heat from the heating rollers, the number of compensation rollers should be set according to the space inside the printer and the actual heating efficiency.

[0008] This application does not specifically limit the shape of the compensating roller. Any shape of compensating roller that can offset at least part of the pressure based on the above technical solutions is within the scope of protection of this application. In some implementations of this application, the compensating roller is cylindrical. A cylinder is easy to process and can subject the heating roller to a uniform compensating force distributed along its axial direction. In other implementations of this application, the compensating roller is spindle-shaped, with its diameter gradually decreasing from the middle to both ends. The inventors have discovered that after the compensating roller applies a compensating force to the heating roller for a long time, the compensating roller may also undergo flexural deformation, and the middle section of the compensating roller will bend away from the heating roller. Therefore, the middle section of the compensating roller cannot apply an effective compensating force to the heating roller. This implementation sets the compensating roller to a spindle shape. Since the diameter of the middle section of the spindle is relatively large, when the compensating roller undergoes flexural deformation, the middle section of the compensating roller can still provide an effective compensating force to the heating roller.

[0009] In some implementations of this application, the compensating roller includes a first roller core and a first elastic layer wrapped around the circumferential surface of the first roller core. The first elastic layer is capable of elastic deformation under stress. By providing the first elastic layer, the compensating roller can undergo elastic deformation when pressing the heating roller, thereby increasing the clamping area and preventing damage to the compensating roller due to excessive compensating force.

[0010] In some implementations of this application, the first roller core is made of a metal material, and the first elastic layer is made of rubber or sponge.

[0011] In some implementations of this application, a first anti-stick layer is provided on the circumferential surface of the first elastic layer. The first anti-stick layer is used to prevent toner from sticking to the circumferential surface of the compensation roller, causing paper contamination and affecting image quality.

[0012] In some implementations of this application, the first anti-stick layer is made by drying PTFE resin powder or PFA resin powder applied to the surface of the first elastic layer.

[0013] In some implementations of this application, the heating roller includes a cylinder and a heater disposed inside the cylinder, the heater being used to provide heat to the cylinder.

[0014] In some implementations of this application, the pressure roller includes a second roller core and a second elastic layer wrapped around the circumferential surface of the second roller core. The second elastic layer is capable of elastic deformation under stress. By providing the second elastic layer, the pressure roller can undergo elastic deformation when pressing the heating roller, forming an arc-shaped clamping area, thereby increasing the clamping width between the pressure roller and the heating roller, improving the toner pressing effect, and preventing damage to the pressure roller.

[0015] Secondly, this application provides a printer that includes a fixing device as described in the first aspect. Attached Figure Description

[0016] Figure 1 The following diagram illustrates the structure of the fixing device in some embodiments of this application. Figure 1 ;

[0017] Figure 2 It shows Figure 1 Side view;

[0018] Figure 3 A schematic diagram of the forces acting on the heating roller in some embodiments of this application is shown;

[0019] Figure 4 A simplified diagram of the forces acting on the heating roller in some embodiments of this application is shown;

[0020] Figure 5(a) shows a schematic diagram of the clamping width of one end of the heating roller in some embodiments of this application;

[0021] Figure 5(b) shows a schematic diagram of the clamping width of the middle section of the heating roller in some embodiments of this application;

[0022] Figure 5(c) shows a schematic diagram of the clamping width at the other end of the heating roller in some embodiments of this application;

[0023] Figure 6 The diagram shows the axial distribution of clamping pressure and clamping width of the heating roller in some embodiments of this application;

[0024] Figure 7 The following diagram illustrates the structure of the fixing device in some embodiments of this application. Figure 2 ;

[0025] Figure 8(a) shows a perspective view of a fixing device in some embodiments of this application;

[0026] Figure 8(b) shows the front view of Figure 8(a);

[0027] Figure 9 A schematic diagram of a heating roller in some embodiments of this application is shown;

[0028] Figure 10 Cross-sectional views of heating rollers and pressure rollers in some embodiments of this application are shown;

[0029] Figure 11(a) shows a schematic diagram of the structure of a fixing device having a compensation roller in some embodiments of this application;

[0030] Figure 11(b) shows a cross-sectional view of a fixing device having a compensation roller in some embodiments of this application;

[0031] Figure 12(a) shows a schematic diagram of a fixing device with two compensation rollers in some embodiments of this application;

[0032] Figure 12(b) shows a cross-sectional view of a fixing device with two compensation rollers in some embodiments of this application;

[0033] Figure 12(c) shows a perspective view of a fixing device with two compensation rollers in some embodiments of this application;

[0034] Figure 13 A schematic diagram of a fixing device with three compensation rollers is shown in some embodiments of this application;

[0035] Figure 14(a) shows a schematic diagram of the compensation roller in some embodiments of this application. Figure 1 ;

[0036] Figure 14(b) shows a schematic diagram of the compensation roller in some other embodiments of this application. Figure 2 ;

[0037] Figure 15(a) shows Figure 10 A magnified view of part A in the middle;

[0038] Figure 15(b) shows Figure 10 A magnified view of part B in the middle section.

[0039] Figure 16(a) shows a schematic diagram of the fixing device in the compression process in some embodiments of this application;

[0040] Figure 16(b) shows a schematic diagram of the fixing device in the heat transfer process in some embodiments of this application;

[0041] Figure 16(c) shows a schematic diagram of the fixing device in the softening and bonding process in some embodiments of this application;

[0042] Figure 16(d) shows a schematic diagram of the fixing device in some embodiments of this application during the flow expansion process;

[0043] Figure 16(e) shows a schematic diagram of the fixing device in the crimping penetration process in some embodiments of this application;

[0044] Figure 16(f) shows a schematic diagram of the fixing device in the separation and cooling process in some embodiments of this application.

[0045] Explanation of reference numerals in the attached figures:

[0046] 1-Heating roller; 11-Central axis; 12-Cylinder; 121-Interface; 13-Third elastic layer; 14-Third anti-stick layer; 15-Heater; 16-Third support component;

[0047] 2-Pressure roller; 21-Second roller core; 22-Second elastic layer; 23-Second anti-stick layer; 24-Second support member;

[0048] 3-Compensation roller; 31-First roller core; 32-First elastic layer; 33-First anti-stick layer; 34-First support member;

[0049] 4-Reference plane;

[0050] 5-Transmission mechanism;

[0051] 100 - Paper;

[0052] 200-Toner. DETAILED DESCRIPTION

[0053] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0054] This application provides a fixing device disposed within a printer, used to fix an unfixed image of target image information as a permanent fixed image onto the surface of a recording material. Exemplarily, the recording material can be paper. The fixing device heats and presses the paper, which has been electrostatically adsorbed with toner and passed from an upstream module, to solidify the toner onto the paper, thereby achieving the fixing purpose. (Reference) Figure 1 and Figure 2In some embodiments, the fixing device includes a heating roller 1 and a pressure roller 2. The heating roller 1 has a central axis 11 along its length and is rotatable about the central axis 11. The pressure roller 2 is parallel to the heating roller 1 and contacts the circumferential surface of the heating roller 1. The pressure roller 2 applies radial pressure to the heating roller 1 to compress the paper 100 and toner 200 passing between the pressure roller 2 and the heating roller 1. As the paper 100 passes between the pressure roller 2 and the heating roller 1, the heating roller 1 and the pressure roller 2 clamp and convey the paper 100. The heating roller 1 heats the paper 100, melting the toner 200 on the surface of the paper 100. Simultaneously, the pressure roller 2 and the heating roller 1 compress the paper 100, causing the toner 200 to penetrate into the paper 100 and solidify on the paper 100, forming a firm image. However, printers equipped with the aforementioned fixing device will experience a gradual decline in print quality after a period of use. When the print quality can no longer meet the needs of consumers, the printer can no longer be used, which leads to poor stability of print quality and a short lifespan for the printer.

[0055] The inventors discovered that the main reason for the gradual deterioration of print quality after a period of use is that the heating roller 1 in the fuser unit continuously bears pressure from the pressure roller 2, causing it to bend and deform after prolonged use. (Reference) Figure 3 and Figure 4 , Figure 3 A schematic diagram of the forces acting on the heating roller 1 in the fixing mechanism is shown. Figure 4 A simplified force diagram of the heating roller 1 in the fixing mechanism is shown. The pressure applied by the pressure roller 2 to the heating roller 1 is as follows: Figure 3 and Figure 4 As shown by the pressure F, when the heating roller 1 undergoes flexural deformation under the action of pressure F, the deformation state of the heating roller 1 is as follows. Figure 3 and Figure 4 As shown by the dotted lines in the figure, as the amount of bending deformation of the heating roller 1 increases, the clamping pressure and clamping width of the heating roller 1 and the pressure roller 2 on the paper 100 will be unevenly distributed. For example, dimension D1 in Figure 5(a) and dimension D3 in Figure 5(c) represent the clamping width at both ends of the heating roller 1, respectively, and dimension D2 in Figure 5(b) represents the clamping width in the middle section of the heating roller 1. As can be seen from Figures 5(a), 5(b), and 5(c), when the heating roller 1 undergoes bending deformation, the clamping width at both ends of the heating roller 1 is significantly greater than the clamping width in the middle section of the heating roller 1. Furthermore, Figure 6 This is an axial distribution diagram of the clamping pressure and clamping width of heating roller 1, from... Figure 6It can be seen that the clamping pressure at both ends of heating roller 1 is significantly greater than the clamping pressure in the middle section of heating roller 1. Uneven distribution of clamping width and clamping pressure will affect the stability of print quality and the lifespan of the printer.

[0056] To address the issues of poor print quality stability and short printer lifespan, some implementations in this application reference... Figure 7 The fixing device also includes a compensating roller 3, which is parallel to the heating roller 1 and can rotate around its own axis. The circumferential surface of the compensating roller 3 is in contact with the circumferential surface of the heating roller 1. The compensating roller 3 is used to apply a compensating force along the radial direction of the heating roller 1 to the heating roller 1 to counteract at least part of the pressure from the pressure roller 2 (such as...). Figure 7 (As shown in the pressure F). Since the middle section of the heating roller 1 is supported by the compensation roller 3, this application can reduce the amount of deflection deformation of the heating roller 1 under pressure by setting the compensation roller 3, so that the clamping pressure and clamping width between the heating roller 1 and the pressure roller 2 are evenly distributed along the axial direction, thereby improving the service life of the equipment and the stability of the printed image quality. In addition, by setting the compensation roller 3 to reduce the deformation of the heating roller 1, the strength of the heating roller 1 can also be appropriately reduced, thereby reducing the thickness and mass of the heating roller 1, reducing the heat capacity of the heating roller 1, and realizing fast response printing.

[0057] In some implementations of this application, referring to FIG8(a), a third support member 16 is provided at each end of the heating roller 1, and the heating roller 1 and the third support member 16 are hinged to each other. A second support member 24 is provided at each end of the pressure roller 2, and the pressure roller 2 and the second support member 24 are hinged to each other. A first support member 34 is provided at each end of the compensation roller 3, and the compensation roller 3 and the first support member 34 are hinged to each other.

[0058] In the actual operation of the product, the compensation roller 3 is generally located above the heating roller 1, and the pressure roller 2 is generally located below the heating roller 1.

[0059] Furthermore, referring to Figure 8(b), the heating roller 1 is connected to the transmission mechanism 5, which is used to drive the heating roller 1 to rotate so that the heating roller 1 can drive the pressure roller 2 and the compensation roller 3 to rotate.

[0060] Furthermore, refer to Figure 8(b) and Figure 9 The heating roller 1 may be provided with an interface 121 at its end. The interface 121 is used to connect with the transmission mechanism 5 so that the heating roller 1 can be connected to the transmission mechanism 5.

[0061] Further reference Figure 9 and Figure 10The heating roller 1 includes a cylinder 12 and a heater 15 disposed within the cylinder 12. The cylinder 12 can be made of a metal with good thermal conductivity and rigidity (e.g., aluminum, iron, or stainless steel). The heater 15 can be a halogen lamp. The heater 15 is mounted inside the cylinder 12 via a bracket and is used to provide heat to the cylinder 12 to heat the carbon powder 200 passing between the heating roller 1 and the pressure roller 2. Figure 10 As shown, when the fixing unit is working, the module upstream of the fixing unit transfers the paper 100 with toner 200 adsorbed onto it between the heating roller 1 and the pressure roller 2. The paper 100 passes between the heating roller 1 and the pressure roller 2 under the rotation of the heating roller 1. During this process, the heating roller 1 and the pressure roller 2 compress the paper 100 and the toner 200.

[0062] Figures 16(a) to 16(d) The diagram illustrates the state of paper 100 and toner 200 during the fixing process. As shown in Figure 16(a), when the toner 200 on the surface of paper 100 and paper 100 are initially squeezed by heating roller 1 and pressure roller 2, the originally randomly arranged toner 200 tends to become flat and evenly distributed. Simultaneously, heating roller 1 transfers heat outward to heat the toner 200, as shown in Figure 16(b). The heated toner 200 softens, as shown in Figure 16(c), and after softening and combining, it expands outward, as shown in Figure 16(d). The expanded toner 200, under the squeezing action of heating roller 1 and pressure roller 2, is pressed and penetrates onto paper 100, as shown in Figure 16(e), and solidifies on paper 100 to form the target image. After solidification, heating roller 1 and pressure roller 2 convey paper 100 to the next process, separating paper 100 from heating roller 1 and pressure roller 2, as shown in Figure 16(f), to allow paper 100 to cool.

[0063] This application does not specifically limit the number of compensating rollers 3. Any number of compensating rollers 3 that can offset at least part of the pressure based on the above technical solutions are within the scope of protection of this application. In some implementations of this application, as shown in Figures 11(a) and 11(b), the number of compensating rollers 3 is one, and the compensating roller 3 and the pressure roller 2 are arranged opposite each other on both sides of the heating roller 1 along the radial direction. The inventors have discovered that when the compensating roller 3 comes into contact with the heating roller 1, the compensating roller 3 will disperse the heat of the heating roller 1. Therefore, by setting only one compensating roller 3, the heat loss of the heating roller 1 can be reduced and the heating efficiency of the heating roller 1 can be improved. In other implementations of this application, the number of compensating rollers 3 is at least two, and each compensating roller 3 is arranged at intervals along the circumference of the heating roller 1. The plane in which the axis of the heating roller 1 and the axis of the pressure roller 2 are located is the reference plane 4. When the number of compensating rollers 3 is even, as shown in Figures 12(a), 12(b), and 12(c), each compensating roller 3 is distributed on both sides of the reference plane 4. More preferably, each compensating roller 3 is distributed mirror-symmetrically on both sides of the reference plane 4. When the number of compensating rollers 3 is an odd number greater than 2, such as... Figure 13 As shown, the axis of one compensation roller 3 is located on the reference plane 4, and the remaining compensation rollers 3 are distributed on both sides of the reference plane 4. More preferably, the remaining compensation rollers 3 are symmetrically distributed on both sides of the reference plane 4. By setting multiple compensation rollers 3, the deformation at multiple positions of the heating roller 1 can be compensated, thereby improving the compensation effect. However, compared to setting a single compensation roller, setting multiple compensation rollers occupies more space, and the compensation rollers distribute the heat of the heating roller 1 more. Therefore, the number of compensation rollers 3 should be set according to the space inside the printer and the actual heating efficiency.

[0064] This application does not specifically limit the shape of the compensating roller 3. Any shape of the compensating roller 3 that can offset at least part of the pressure based on the above technical solutions is within the scope of protection of this application. In some implementations of this application, as shown in FIG14(a), the compensating roller 3 is cylindrical. A cylinder is easy to process and can make the heating roller 1 receive a uniform compensating force distributed along its axial direction. In other implementations of this application, as shown in FIG14(b), the compensating roller 3 is spindle-shaped, and the diameter of the compensating roller 3 gradually decreases from the middle to both ends. The inventors have discovered that after the compensating roller 3 applies a compensating force to the heating roller 1 for a long time, the compensating roller 3 may also undergo flexural deformation, and the middle section of the compensating roller 3 will bend away from the heating roller 1. Therefore, the middle section of the compensating roller 3 cannot apply an effective compensating force to the heating roller 1. This implementation sets the compensating roller 3 to a spindle shape. Since the diameter of the middle section of the spindle shape is large, when the compensating roller 3 undergoes flexural deformation, the middle section of the compensating roller 3 can still provide an effective compensating force to the heating roller 1.

[0065] In some implementations of this application, as shown in Figures 11(b) and 12(b), the compensation roller 3 includes a first roller core 31 and a first elastic layer 32 wrapped around the circumferential surface of the first roller core 31. The first elastic layer 32 is capable of elastic deformation under stress. Exemplarily, the first roller core 31 is made of a metal material, and the first elastic layer 32 is made of rubber or sponge. By providing the first elastic layer 32, the compensation roller 3 can undergo elastic deformation when pressing the heating roller 1, thereby increasing the clamping area between the heating roller 1 and the compensation roller 3, improving the stress-bearing effect of the heating roller 1, and preventing damage to the compensation roller 3 due to excessive compensation force.

[0066] In some implementations of this application, as shown in Figures 11(b) and 12(b), a first anti-stick layer 33 is provided on the circumferential surface of the first elastic layer 32. The first anti-stick layer 33 is used to prevent the toner 200 from sticking to the circumferential surface of the compensation roller 3, causing contamination of the paper 100 conveyed subsequently, and thus affecting the printing quality. Exemplarily, the first anti-stick layer 33 is made by drying PTFE resin powder or PFA resin powder coated on the surface of the first elastic layer 32.

[0067] In some implementations of this application, as shown in FIG15(a), the pressure roller 2 includes a second roller core 21 and a second elastic layer 22 wrapped around the circumferential surface of the second roller core 21. The second roller core 21 can be made of a metal with excellent rigidity (e.g., aluminum, iron, or stainless steel), and the second elastic layer 22 can undergo elastic deformation under stress. A second anti-stick layer 23 is provided on the outer circumferential surface of the second elastic layer 22 to prevent the toner 200 from sticking to the circumferential surface of the pressure roller 2. Exemplarily, the second elastic layer 22 can be made of rubber with good oil resistance, such as silicone rubber, fluororubber, etc. By providing the second elastic layer 22, when the pressure roller 2 presses the heating roller 1, the second elastic layer 22 can undergo elastic deformation to form an arc-shaped clamping area, thereby increasing the clamping width between the pressure roller 2 and the heating roller 1, improving the toner pressing effect, and preventing damage to the pressure roller 2. The second anti-stick layer 23 is manufactured in the same way as the first anti-stick layer 33. By setting the second anti-stick layer 23, the toner 200 can be prevented from sticking to the circumferential surface of the pressure roller 2, causing paper contamination and affecting the image quality.

[0068] In some implementations of this application, as shown in FIG15(b), a third elastic layer 13 is provided on the outer circumferential surface of the cylinder 12. The third elastic layer 13 is capable of elastic deformation under stress. A third anti-stick layer 14 is provided on the outer circumferential surface of the third elastic layer 13. The third anti-stick layer 14 is used to prevent the toner 200 from sticking to the circumferential surface of the heating roller 1. Exemplarily, the third elastic layer 13 can be made of rubber with good oil resistance, such as silicone rubber, fluororubber, etc. By providing the third elastic layer 13, the pressure roller 2 can prevent the heating roller 1 from being damaged when it is pressing the heating roller 1. The third anti-stick layer 14 is manufactured in the same way as the first anti-stick layer 33. By providing the third anti-stick layer 14, the toner 200 can be prevented from sticking to the circumferential surface of the heating roller 1, causing paper 100 contamination and affecting image quality.

[0069] This application also provides a printer, including the one described in the foregoing embodiments. Figure 1-1 6. Any of the fixing devices described.

[0070] In some implementations of this application, the printer can be a laser printer. A laser printer is an output device that combines laser scanning technology and electro-imaging technology. While the functions of different laser printer models may vary, their operating sequence and principles are essentially the same. The operating steps of a laser printer are as follows:

[0071] When a user sends a print command to the printer through the computer operating system, the printer driver first converts the graphic information to be printed into binary information and then transmits it to the main control board.

[0072] The main control board receives binary information from the driver program, interprets it, and modulates it onto the laser beam, controlling the laser emission based on this information. Simultaneously, the surface of the photosensitive drum is charged by a charging device, and then a laser scanning mechanism generates a laser beam carrying graphic information to expose the photosensitive drum, forming an electrostatic latent image on the surface of the drum after exposure.

[0073] After the drum comes into contact with the developing unit, the latent image becomes a visible image. When it passes through the transfer unit, the toner is transferred onto the paper under the action of the electric field of the transfer unit.

[0074] After the transfer is complete, the paper comes into contact with the electrostatic oscillator teeth and releases the charge on the paper towards the ground. Finally, the paper with toner adsorbed enters the fixing device provided in this application. After the fixing device heats and squeezes the paper and toner, the image formed by the toner is fused onto the paper.

[0075] After printing the graphic information, the cleaning device removes the toner that has not been transferred, and then the next work cycle begins.

[0076] All of the above processes require seven steps: charging, exposure, development, transfer, static elimination, fixing, and cleaning.

[0077] The specific embodiments described above illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Although the description of this application is presented in conjunction with some embodiments, this does not mean that the features of this application are limited to this embodiment. On the contrary, the purpose of describing the application in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of this application. This application may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of this application, some specific details have been omitted in the description. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0078] In the embodiments of this application, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.

[0079] In the embodiments of this application, "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0080] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. The directional terms mentioned in the embodiments of this application, such as "left," "right," "inner," and "outer," are only for reference to the directions in the accompanying drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of this application, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. "Multiple" refers to at least two.

[0081] In the description of this application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "outer", "inner", "circumferential", "radial", "axial", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0082] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "set," "install," "connect," and "fit" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0083] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A fixing device, characterized in that: include: A heating roller having a central axis along its length, the heating roller being rotatable around the central axis; a pressure roller, parallel to the heating roller, wherein the circumferential surface of the pressure roller contacts the circumferential surface of the heating roller so as to apply pressure to the heating roller in the radial direction of the heating roller; The compensation roller is parallel to the heating roller, the circumferential surface of the compensation roller contacts the circumferential surface of the heating roller, and the compensation roller is used to apply a compensation force to the heating roller along the radial direction of the heating roller to offset at least part of the pressure.

2. The fixing device according to claim 1, characterized in that: The number of the compensation roller is one, and the compensation roller and the pressure roller are arranged on both sides of the heating roller opposite to each other along the radial direction of the heating roller.

3. The fixing device according to claim 1, characterized in that: The number of the compensation rollers is at least two, and the compensation rollers are arranged at intervals along the circumference of the heating roller, and the plane where the axis of the heating roller and the axis of the pressure roller are located together is the reference plane; when the number of the compensation rollers is an even number, the compensation rollers are distributed on both sides of the reference plane; when the number of the compensation rollers is an odd number, the axis of one of the compensation rollers is located on the reference plane, and the remaining compensation rollers are distributed on both sides of the reference plane.

4. The fixing device according to claim 3, characterized in that: The number of the compensation rollers distributed on both sides of the reference plane is equal and they are arranged in a mirror-symmetrical manner with respect to the reference plane.

5. The fixing device according to claim 1, characterized in that: The compensation roller is in the shape of a cylinder.

6. The fixing device according to claim 1, characterized in that: The shape of the compensation roller is spindle-shaped, and the diameter of the compensation roller gradually decreases from the middle to both ends.

7. The fixing device according to claim 1, characterized in that: The compensation roller comprises: A first roller core; The first elastic layer is wrapped on the circumferential surface of the first roller core, and the first elastic layer can generate elastic deformation when subjected to force.

8. The fixing device according to claim 7, characterized in that: The first roller core is made of metal material, and the first elastic layer is made of rubber or sponge.

9. The fixing device according to claim 7, characterized in that: A first anti-sticking layer is disposed on the circumferential surface of the first elastic layer, and the first anti-sticking layer is used to prevent carbon powder from adhering to the circumferential surface of the compensation roller.

10. The fixing device according to claim 9, characterized in that: The first anti-sticking layer is made of PTFE resin powder or PFA resin powder coated on the surface of the first elastic layer and then dried.

11. The fixing device according to any one of claims 1 to 10, characterized in that: The heating roller comprises: Cylinder; A heater is arranged in the cylinder, and the heater is used to provide heat for the cylinder.

12. The fixing device according to any one of claims 1 to 10, characterized in that: The pressure roller comprises: The second roller core, The second elastic layer is wrapped on the circumferential surface of the second roller core, and the second elastic layer can generate elastic deformation under the condition of being subjected to force.

13. A printer, characterized in that: The fixing device comprises the fixing device according to any one of claims 1 to 12.

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