Fixing unit and printing equipment

Abstract

The embodiment of the invention discloses a fixing unit and printing equipment. The printing apparatus may specifically be a laser printing apparatus, and the fixing unit may be used in the printing apparatus. The fixing unit includes a heating roller and a pressure bearing roller. The heating roller is used for providing heat. The pressure-bearing roller comprises a mandrel and a deformable pressure-bearing part, the pressure-bearing part is located on the radial outer side of the mandrel, and the pressure-bearing part is filled with a flowable medium. The pressure-bearing part filled with the flowable medium can provide larger deformation amount, the width of the formed elastic deformation area is obviously increased, then larger heating stroke and heat conduction efficiency can be provided, and rapid fixing and printing can be achieved. Moreover, the pressure-bearing part filled with the flowable medium can better solve the problem of stress concentration of the elastic clamping area, and is beneficial to ensuring the consistency of the fixing strength; meanwhile, according to the scheme, the heating stroke can be increased without replacing a pressure-bearing roller with a larger size, and miniaturization of the fixing unit and the printing equipment is facilitated.

Description

Technical Field

[0001] The present application relates to the technical field of printing equipment, and in particular to a fixing unit and a printing equipment. Background Art

[0002] The fixing unit is commonly found in printing devices such as laser printers, and is used to heat and melt the developer so as to penetrate the developer into the recording medium, thereby solidifying the developer on the recording medium.

[0003] In the related art, the fixing unit includes a heating roller and a rubber roller. When printing, the recording medium can be located between the heating roller and the rubber roller, the heating roller can press the rubber roller, and the surface of the rubber roller can form an elastic clamping area, and the recording medium and the developer attached to the surface of the recording medium can be heated by the heating roller in the elastic clamping area. The size of the elastic clamping area will directly affect the fixing quality and fixing efficiency. However, the elastic deformation of the rubber roller is limited. If the elastic clamping area is to be increased, the diameter of the rubber roller can only be increased, but this is not conducive to the miniaturization of the fixing unit and the printing device.

[0004] Therefore, how to provide a solution to overcome or alleviate the above-mentioned defects is still a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] The embodiments of the present application provide a fixing unit and a printing device, wherein the pressure roller of the fixing unit is deformed under pressure by means of a flowable medium, and can provide a greater elastic deformation, thereby providing a greater heating stroke and thermal conductivity efficiency, which is beneficial to improving the fixing efficiency, and can better solve the stress concentration problem in the elastic clamping area, can improve the consistency of the fixing strength, and can also improve the fixing quality.

[0006] In the first aspect, the present application provides a fixing unit which can be applied to a printing device in the form of a laser printer, etc., and includes a heating roller and a pressure roller. The heating roller is used to provide heat; the pressure roller includes a core shaft and a deformable pressure bearing portion, the pressure bearing portion is located radially outside the core shaft, and the pressure bearing portion is filled with a flowable medium.

[0007] During fixing, the heating roller can apply pressure to the pressure-bearing part through the recording medium, and the flowable medium in the pressure-bearing part can flow to form an elastic clamping area under the action of the heating roller. Different from the rubber roller in the related art, the pressure-bearing part filled with the flowable medium can provide a larger deformation amount, and the width of the elastic deformation area formed is significantly increased, which can provide a larger heating stroke and thermal conductivity efficiency, which is conducive to achieving rapid fixing and printing. In addition, the pressure-bearing part filled with the flowable medium can also better solve the stress concentration problem in the elastic clamping area, so that each position of the elastic clamping area can generate a relatively uniform rebound force, which is conducive to ensuring the consistency of the fixing strength, so as to improve the fixing and printing quality.

[0008] At the same time, the above solution does not require the replacement of a larger-sized pressure roller, that is, the heating stroke can be increased. Therefore, it can meet the miniaturization design requirements of the fixing unit and the printing equipment, which is conducive to the development of printing equipment towards civilian, home and portable directions.

[0009] The amount of the flowable medium in the pressure-bearing part is not limited in the present embodiment. That is, even if the pressure-bearing part is of the same size, those skilled in the art can selectively adjust the amount of the flowable medium in the pressure-bearing part, and thus provide a pressure-bearing part with different elastic properties to meet the requirements of use.

[0010] Based on the first aspect, the embodiment of the present application further provides a first implementation of the first aspect: the pressure-bearing portion includes a cylindrical bladder skin, the bladder skin outer shell is assembled on the core shaft, and the axial ends of the bladder skin are respectively fixed to the core shaft; the bladder skin and the core shaft enclose a mounting chamber, and the flowable medium is filled in the mounting chamber. In this case, the mounting chamber is formed by the bladder skin and the core shaft, and the amount of bladder skin used can be relatively small.

[0011] In this embodiment, a withdrawal port may be provided on the bladder skin so that the flowable medium can be injected or withdrawn through the withdrawal port; or, a connecting channel may be provided on the core shaft, and the connecting channel may be connected to the installation chamber, so that the flowable medium can be withdrawn through the connecting channel.

[0012] Based on the first aspect, the embodiment of the present application also provides a second implementation of the first aspect: the pressure-bearing portion includes an annular bladder, and the bladder jacket is assembled on the core shaft. At this time, the bladder itself can form an installation chamber for filling the flowable medium without being enclosed together with the core shaft, and the sealing is relatively easy to ensure. In this embodiment, a withdrawal port can be set on the bladder so that the flowable medium can be injected or extracted through the withdrawal port.

[0013] Based on the first aspect, or based on the first implementation or the second implementation of the first aspect, the embodiment of the present application further provides a third implementation of the first aspect: the flowable medium is a fluid medium or a bulk material.

[0014] The fluid medium can be, for example, a liquid or a gas. For example, if the fluid medium is a gas, the fluid medium can be air or nitrogen. For example, if the fluid medium is a liquid, the fluid medium can be water, oil, etc. The fluid medium can have better flow properties, and it is not easy to get clogged during the process of pumping the flowable medium in the pressure-bearing part; and the driving part in the pumping device only needs to use an ordinary driving pump, and the structure can be relatively simple, which is more conducive to implementation.

[0015] Bulk materials can be, for example, sand, grains, sawdust, etc. Compared with the above-mentioned fluid medium, the cost of bulk materials is lower, which is conducive to reducing the cost of the fixing unit provided in the embodiment of the present application; moreover, bulk materials are not prone to leakage, and the requirements for sealing are relatively low.

[0016] Based on the first aspect, or based on any one of the first to third embodiments of the first aspect, the embodiment of the present application also provides a fourth embodiment of the first aspect: the flowable medium is a fluid medium; the core shaft is provided with a connecting channel, the fixing unit also includes a medium source, the medium source is configured with a connecting pipeline, the connecting pipeline and the connecting channel are connected, and the fluid medium can flow into the pressure-bearing part through the connecting pipeline and the connecting channel, or flow out of the pressure-bearing part.

[0017] The mandrel is a rigid component, and it is relatively simple to process a connecting channel on it, and it can be easily connected to an external connecting pipeline, and the reliability of the connection is also easy to ensure. At the same time, providing a connecting channel on the mandrel will also reduce the weight of the mandrel, which itself is also conducive to the lightweight design of the fixing unit.

[0018] Depending on the type of fluid medium, the medium source can be selected between a gas source and a liquid source. The connecting pipeline can be equipped with a switch valve and a drive pump; the drive pump is used to provide a driving force for the connecting pipeline to realize the flow of the fluid medium to the pressure-bearing part or the medium source; the switch valve is used to adjust the flow rate and the connection state of the connecting pipeline.

[0019] Based on the fourth implementation of the first aspect, the present application also provides a fifth implementation of the first aspect: the mandrel is provided with a joint, and the joint is connected to the connecting pipeline. The joint can match the interface difference between the mandrel and the connecting pipeline, and can realize the switching of the mandrel and the connecting pipeline.

[0020] It should be understood that in some other implementations of the embodiments of the present application, the joint can also be replaced by a plug, which can block the connecting channel to achieve independent operation of the pressure roller under conditions without connecting pipelines.

[0021] Based on the first aspect, or based on any one of the first to fifth embodiments of the first aspect, the embodiment of the present application further provides a sixth embodiment of the first aspect: a second anti-sticking layer is provided on the outer wall surface of the pressure-bearing portion to reduce the adhesion of the developer and the like to the pressure-bearing portion during the fixing process. The material of the second anti-sticking layer can be polytetrafluoroethylene, soluble polytetrafluoroethylene, etc.; during specific manufacturing, polytetrafluoroethylene or soluble polytetrafluoroethylene can be powdered on the outer wall surface of the pressure-bearing portion, and then dried to form the above-mentioned second anti-sticking layer.

[0022] Similarly, the outer wall surface of the heating roller may also be provided with a first anti-sticking layer, which may also reduce the adsorption of the developer etc. by the heating roller during the fixing process. The material of the first anti-sticking layer may refer to the second anti-sticking layer mentioned above.

[0023] Based on the first aspect, or based on any one of the first to sixth embodiments of the first aspect, the embodiment of the present application further provides a seventh embodiment of the first aspect: the heating roller includes a roller and a first heater, at least part of the first heater is located on the inner side of the roller, and the heating roller presses the pressure roller through the roller. The first heater can specifically be a halogen lamp, a resistance heating wire, etc., and the first heater can indirectly transfer heat to the recording medium and the developer through the roller. In addition, since the roller is a circular cylinder, when the pressure roller is pressurized by the roller, the elastic clamping area formed is arc-shaped.

[0024] Based on the first aspect, or based on any one of the first to sixth embodiments of the first aspect, the embodiment of the present application further provides an eighth embodiment of the first aspect: the heating roller includes a fixing film and a second heater; the fixing film is cylindrical, and the second heater is plate-shaped; the second heater is located in the fixing film, and the second heater can be displaced in the fixing film; the second heater can abut the fixing film with one of its plate surfaces, and can pressurize the pressure roller through the fixing film. In this way, the elastic clamping area formed is roughly planar, which can reduce the bending deformation of the recording material.

[0025] In this embodiment, the heating roller may also be provided with a driving member, which may be in driving connection with the bracket to drive the bracket to perform linear displacement, and further drive the second heater to perform linear displacement. The driving member may specifically be a driving element that can directly output linear displacement, such as a cylinder or a hydraulic cylinder; or the driving member may also be a driving element in the form of a motor, in which case the driving member may also include a displacement conversion mechanism in the form of a gear rack mechanism, a lead screw mechanism, etc., so as to convert the rotational displacement output by the motor into the linear displacement required by the bracket.

[0026] In the second aspect, an embodiment of the present application further provides a printing device, which can be specifically a laser printing device, including a shell and a fixing unit, the fixing unit is arranged in the shell, and the fixing unit is the fixing unit involved in the first aspect or any one of the embodiments of the first aspect.

[0027] In the above printing device, the pressure-bearing part of the fixing unit is filled with a flowable medium, and the pressure-bearing deformation is carried out by the flowable medium, which can provide a larger deformation amount and ensure a relatively uniform resilience, which is conducive to ensuring printing efficiency and printing quality. At the same time, the fixing unit does not need to be equipped with a larger pressure roller, which can meet the design requirements of the miniaturization of the printing device, and is conducive to the development of the printing device in the direction of civilian, household and portable use. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of a structure of an implementation method of a printing device provided in an embodiment of the present application;

[0029] Figure 2 for Figure 1 The structural diagram of the printing module;

[0030] Figure 3 is a graph showing the relationship between the deformation of the rubber roller and the pressure it bears;

[0031] Figure 4 is a curve diagram of pressure variation at different positions of the elastic clamping area of ​​the rubber roller;

[0032] Figure 5 A simplified structural diagram of an implementation method of a fixing unit provided in an embodiment of the present application;

[0033] Figure 6 for Figure 5 Axial cross-sectional view of the heating roller and the pressure roller;

[0034] Figure 7 A pressure variation curve diagram of different positions of the elastic clamping area of ​​the pressure bearing roller in the embodiment of the present application;

[0035] Figure 8A simplified structural diagram of another implementation of the fixing unit provided in the embodiment of the present application;

[0036] Fig. 9 for Figure 8 Status diagram of the use of the fixing unit with different recording media;

[0037] Fig.10 A three-dimensional diagram of a fixing unit provided in an embodiment of the present application in one implementation manner;

[0038] Fig.11 for Fig.10 A cross-sectional view perpendicular to the axial direction;

[0039] Fig.12 for Fig.10 A front view of

[0040] Fig.13 for Fig.10 Axial cross-section of

[0041] Fig.14 for Fig.10 A schematic diagram of the structure of the heating roller;

[0042] Fig.15 It is a structural schematic diagram of another implementation method of the pressure roller in the embodiment of the present application;

[0043] Fig.16 It is a structural schematic diagram of another implementation method of the heating roller in the embodiment of the present application. DETAILED DESCRIPTION

[0044] In order to enable those skilled in the art to better understand the technical solution of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0045] In the description of the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0046] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. 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.

[0047] The directional terms mentioned in the embodiments of the present application, such as "inside", "outside", etc., are only references to the directions of the drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of the present application, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0048] In the description of the embodiments of the present application, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0049] Please refer to Figure 1 and Figure 2 , Figure 1 A schematic diagram of a structure of an implementation method of a printing device provided in an embodiment of the present application. Figure 2 for Figure 1 Schematic diagram of the structure of the printing module.

[0050] like Figure 1 and Figure 2 As shown, an embodiment of the present application provides a printing device 100 , which may be a laser printer, for example, including a housing 110 and a printing module 120 , and the printing module 120 may be disposed in the housing 110 .

[0051] The housing 110 is the outer frame of the printing device 100, and is used to realize the integrated assembly of the printing module 120 and to protect the printing module 120, thereby reducing the possibility of damage to the printing module 120 during installation and use. In addition, the housing 110 also basically determines the overall shape of the printing device 100. Figure 1 As shown, the housing 110 may be in the form of a rectangular parallelepiped. Of course, the housing 110 may also be in other structural forms as long as the realization of the printing function is not affected.

[0052] In some implementations, the housing 110 is also provided with a display screen and some operation buttons. The display screen is used to display the working status information of the printing device 100, and the operation buttons can be used to control the printing device 100. The display screen can be a touch screen, in which case the operation buttons can be virtual buttons located on the display screen. Alternatively, the display screen can also only have a display function, in which case the operation buttons can be physical buttons set on the housing 110. The number and setting positions of the display screen and the operation buttons are not limited here. In specific practice, those skilled in the art can design them according to actual needs.

[0053] The printing module 120 is a core module of the printing device 100, and is used to print the electronic version of the target image stored in the electronic device according to the printing command issued by the user through the electronic device in the form of a computer, a mobile phone, etc. Figure 2 As shown, in some implementations, the printing module 120 may include a control unit 121 , a scanning unit 122 , a photosensitive drum 123 , a charging unit 124 , a developing unit 125 , a transfer unit 126 , a fixing unit 127 , and a cleaning unit 128 .

[0054] It should be understood that the structure illustrated in the embodiment of the present application does not constitute a specific limitation on the printing module 120. In other embodiments of the present application, the printing module 120 may include more or fewer components than shown in the figure, or combine some components, or split some components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0055] The control unit 121 is the nerve center and command center of the printing module 120. The control unit 121 can generate control signals to control other unit modules so that the various unit modules work in coordination; that is, the control unit 121 can be connected to other unit modules that require electrical signal control by signals, so as to transmit signals between other unit modules; for example, the control unit 121 can be connected to the scanning unit 122 by signals to control the scanning unit 122 to work. In addition, the control unit 121 can also be connected to electronic devices in the form of computers, mobile phones, etc. by signals to receive printing commands from electronic devices.

[0056] The scanning unit 122 may be specifically a laser scanning unit (LSU), including a laser and a scanning component. The control unit 121 may convert the electronic version of the target image into binary information, and may modulate the laser beam generated by the laser in the scanning unit 122 according to the binary information to control the light amount and switching state of the laser beam generated by the laser. The scanning component in the scanning unit 122 may scan the laser beam generated by the laser on the photosensitive surface of the photosensitive drum 123 along the main scanning direction to form a row of scanning spots. The main scanning direction is parallel to the rotation axis of the photosensitive drum 123 (i.e., the central axis of the photosensitive drum 123).

[0057] In some implementations, the scanning assembly may include a collimating lens, a multi-faceted scanning mirror, and an f-θ lens. The collimating lens may collimate the laser beam generated by the laser, so that the laser beam becomes a substantially parallel beam after passing through the collimating lens; the multi-faceted scanning mirror may deflect and scan the laser beam passing through the collimating lens; and the f-θ lens may focus the laser beam passing through the multi-faceted scanning mirror onto the photosensitive surface of the photosensitive drum 123 to form the above-mentioned scanning spot.

[0058] The photosensitive drum 123 can rotate under the drive of a driving component in the form of a motor. Each time the scanning unit 122 completes a scan in the main scanning direction (i.e., scans a line), the photosensitive surface of the photosensitive drum 123 rotates a pixel distance, that is, the scanning spot on the photosensitive surface moves a pixel distance along the photosensitive surface; as the photosensitive drum 123 rotates, the photosensitive surface of the photosensitive drum 123 moves along the sub-scanning direction relative to the laser beam, thereby realizing scanning in the sub-scanning direction. The sub-scanning direction is perpendicular to the main scanning direction and is consistent with the rotation direction of the photosensitive drum 123.

[0059] The charging unit 124 is used to charge the photosensitive drum 123 so that a uniform negative charge is generated on the photosensitive surface of the photosensitive drum 123. The points on the photosensitive surface of the photosensitive drum 123 that are irradiated (i.e., exposed) by the laser beam are discharged, and the charges of the unexposed points remain unchanged. With the scanning of the scanning unit 122 and the rotation of the photosensitive drum 123, the photosensitive surface of the photosensitive drum 123 can form a latent image, i.e., an electrostatic latent image, under the action of the laser beam.

[0060] The developing unit 125 is located downstream of the exposure position of the photosensitive drum 123. As the photosensitive drum 123 rotates, the electrostatic latent image can be rotated to the developing position of the developing unit 125. The developing unit 125 contains a developer Q, which can be specifically carbon powder. The color of the carbon powder can be black, or can also be cyan, yellow, magenta, etc., which can be specifically determined according to the type of the printing device 100. The developer Q carries a negative charge; when the electrostatic latent image on the surface of the photosensitive drum 123 passes through the developing position, the developing unit 125 can apply the developer Q to the photosensitive surface of the photosensitive drum 123; the exposed points in the electrostatic latent image can absorb carbon powder, and the unexposed points repel carbon powder. In this way, under the action of the developer Q, the electrostatic latent image can be developed into a developed image.

[0061] The transfer unit 126 may include a transfer device and a de-electrification device. The transfer device may generate an electric field, and under the action of the transfer device, the developer Q attached to the surface of the photosensitive drum 123 may be transferred to the recording medium P; the recording medium P may specifically be paper in the form of electrostatic copy paper, coated paper, sulfuric acid paper, etc.; the recording medium P may be provided by a paper box (not shown in the figure) located on one side of the photosensitive drum 123, or may be manually fed in by a user. The de-electrification device is located downstream of the transfer device, and is used to neutralize the charges on the recording medium P and the developer Q, which is beneficial to ensure the position accuracy of the developer Q on the recording medium P before fixing.

[0062] The fixing unit 127 is located downstream of the photosensitive drum 123 and is used to melt the developer Q at high temperature so that the developer Q can penetrate into the recording medium P, thereby solidifying the developed image and completing the printing of the target image. The recording medium P after fixing can be transported to the outside of the printing device 100.

[0063] The cleaning unit 128 is used to remove the residual developer Q and charge on the photosensitive surface of the photosensitive drum 123, so that there is a clean photosensitive drum 123 in the next printing cycle. The cleaning unit 128 can be specifically a cleaning component in the form of a scraper, a brush, etc. to clean the photosensitive drum 123. The scraper can be specifically made of urea-formaldehyde resin, etc., to ensure a certain wear resistance and flexibility. The brush can be made of artificial fiber, etc. When the photosensitive drum 123 rotates, the brush rubs against the surface of the photosensitive drum 123 to sweep away the residual toner, and at the same time, the static electricity generated by the friction can be used to absorb the residual toner, so that the toner does not fly and pollute other components in the printing device 100.

[0064] In the above working process, the printing module 120 needs to go through the above seven steps of charging, exposure, development, transfer, de-charge, fixing, and cleaning. Among them, the fixing unit 127 belongs to the light engine component of the printing device 100, which is the heart of the printing device 100 and directly determines the image quality and printing speed of the printing device 100.

[0065] As described in the background technology section, in the related art, the fixing unit includes a heating roller and a rubber roller, and the recording medium can be located between the heating roller and the rubber roller. When printing, the heating roller can press the rubber roller and can form an elastic clamping area on the surface of the rubber roller. The larger the elastic clamping area, the larger the area where the recording medium is located between the heating roller and the rubber roller, which can have a larger heating stroke and thermal conductivity efficiency, which is beneficial to improving the fixing quality and fixing efficiency. On the contrary, the smaller the elastic clamping area, the smaller the area where the recording medium is located between the heating roller and the rubber roller, the heating stroke and thermal conductivity efficiency will be reduced, which will affect the fixing quality and fixing efficiency, and is not conducive to fast and efficient printing.

[0066] Please refer to Figure 3 and Figure 4 , Figure 3 This is the relationship between the deformation of the rubber roller and the pressure it bears. Figure 4 It is a curve diagram of pressure variation at different positions of the elastic clamping area of ​​the rubber roller.

[0067] like Figure 3 As shown, during the initial stress process of the rubber roller 01, the deformation of the rubber roller 01 changes significantly with the pressure, and the width W′ of the elastic clamping area 011 formed on the surface of the rubber roller 01 increases significantly. Figure 3 However, when the deformation of the rubber roller 01 reaches a certain threshold value (e.g., 25%), further increasing the pressure will only have a very limited effect on the deformation of the rubber roller 01 and the width W′ of the elastic clamping area 011. Figure 3 Thus, if the deformation of the rubber roller 01 is to be further increased, the diameter of the rubber roller 01 can only be increased, but this is not conducive to the miniaturization of the fixing unit and the printing device.

[0068] In addition, if Figure 4 As shown, in the elastic clamping area 011 formed by the rubber roller 01, the pressure concentration phenomenon is obvious. Specifically, the pressure is concentrated at the center of the elastic clamping area 011, while the pressure at other positions is obviously much lower. The low pressure position will reduce the fixing strength, resulting in a decrease in the fixing quality.

[0069] In view of this, the embodiment of the present application provides a fixing unit, which uses a flowable medium to deform under pressure. Compared with rubber in a fixed form, the flowable medium can flow under pressure, which can produce a larger elastic clamping area, and the rebound force at each position of the elastic clamping area is relatively uniform, which can achieve a larger heating stroke, higher thermal conductivity and relatively uniform fixing strength, thereby effectively improving the fixing quality and fixing efficiency, which is conducive to achieving fast printing. At the same time, the above solution does not need to increase the size of the fixing unit, can meet the miniaturization design requirements of the fixing unit and the printing device, and is conducive to the development of printing equipment in the direction of civilian, household and portable.

[0070] Please refer to Figure 5-Figure 7 , Figure 5 A simplified structural diagram of an implementation method of a fixing unit provided in an embodiment of the present application, Figure 6 for Figure 5 Axial cross-section of the heating roller and the pressure roller. Figure 7 It is a curve diagram of pressure variation at different positions of the elastic clamping area of ​​the pressure roller in the embodiment of the present application.

[0071] like Figure 5 and Figure 6 As shown, in the embodiment of the present application, the fixing unit 127 includes a heating roller 1 and a pressure roller 2 .

[0072] exist Figure 5 In the implementation mode, the heating roller 1 may include a roller 11 and a first heater 12. The roller 11 may be made of a rigid material, such as aluminum, iron or stainless steel, to ensure a certain strength. At least a portion of the first heater 12 may be located inside the roller 11. The first heater 12 may be a heating element in the form of a halogen lamp, a resistance heating wire, etc. The heat emitted by the first heater 12 may be transferred to the developer Q and the recording medium P through the roller 11.

[0073] The pressure roller 2 includes a core shaft 21 and a deformable pressure-bearing portion 22, the pressure-bearing portion 22 is located radially outside the core shaft 21, and the pressure-bearing portion 22 is filled with a flowable medium 221. The flowable medium 221 can be a fluid medium in the form of gas, liquid, etc., the gas can be, for example, air, nitrogen, etc., the liquid can be, for example, water, oil, etc. Alternatively, the flowable medium 221 can also be a bulk material, for example, sand, grains, wood chips, etc.

[0074] During operation, the heating roller 1 can apply pressure to the pressure-bearing portion 22 through the recording medium P, and the flowable medium 221 in the pressure-bearing portion 22 can flow to form an elastic clamping area 22a under the action of the heating roller 1. Figure 5 and Figure 6Under the action of the heating roller 1, the elastic clamping area 22a formed is roughly arc-shaped. Different from the rubber roller in the related art, the pressure-bearing part 22 filled with the flowable medium 221 can provide a larger deformation amount, and the width W of the elastic deformation area 22a formed is significantly increased, thereby providing a larger heating stroke and heat conduction efficiency, which is conducive to achieving rapid fixing and printing.

[0075] And, if Figure 7 As shown, the pressure-bearing portion 22 filled with the flowable medium 221 can also better solve the stress concentration problem of the elastic clamping area 22a, so that each position of the elastic clamping area 22a can provide a relatively uniform rebound force and interact with the recording medium P, which is beneficial to ensure the consistency of the fixing strength to improve the printing quality.

[0076] In some implementations, such as Figure 6 As shown, the pressure-bearing portion 22 may include a cylindrical bladder skin 222. The bladder skin 222 may be made of rubber with good oil resistance and wear resistance, such as silicone rubber, fluororubber, etc. Of course, the bladder skin 222 may also be made of other materials as long as they can meet the requirements of use.

[0077] The bladder skin 222 can be mounted on the core shaft 21, and both axial ends of the bladder skin 222 can be fixed to the core shaft 21. The specific fixing method includes but is not limited to clamp connection, bonding, etc., as long as the bladder skin 222 and the core shaft 21 can be reliably fixed and the sealing requirements can be met. Figure 6 In the implementation method, the core shaft 21 is provided with two bosses 21a, and the two bosses 21a can be arranged at intervals in the axial direction. The two bosses 21a are both provided with grooves (not marked in the figure), and the two ends of the bladder skin 222 can be respectively installed in the grooves of the two bosses 21a; the two bosses 21a can reduce the impact of the flowable medium 221 on the connection between the bladder skin 222 and the core shaft 21, which is beneficial to ensure the connection reliability between the bladder skin 222 and the core shaft 21, and the setting of the two bosses 21a can also reduce the usage of the bladder skin 222.

[0078] After installation, the capsule skin 222 and the core shaft 21 can enclose a mounting chamber, and the aforementioned flowable medium 221 can be filled in the mounting chamber. In this implementation, the mounting chamber is formed by the capsule skin 222 and the core shaft 21, and the amount of the capsule skin 222 used can be relatively small.

[0079] A connecting channel 211 may also be provided inside the mandrel 21, and the connecting channel 211 may be connected to the installation chamber to realize the injection and extraction of the flowable medium. The mandrel 21 is made of a rigid material, and it is relatively easy to process the connecting channel 211 inside it, and it can be conveniently connected to external pipes, joints, etc., and the reliability of the connection is also easy to ensure. At the same time, the setting of the connecting channel 211 can also reduce the weight of the mandrel 21, and can also achieve the technical purpose of lightweighting.

[0080] In addition, a suction port may be provided on the capsule skin 222 , so that the flowable medium 221 can be suctioned and injected.

[0081] The amount of the flowable medium 221 in the installation chamber can be fixed, that is, it will not change after the printing device 100 leaves the factory, so that only the communication channel 211 provided on the core shaft 21 or the injection port provided on the capsule skin 222 needs to be blocked to prevent the flowable medium 221 from leaking during use. The structure of the entire fixing unit 127 is relatively simple.

[0082] Please refer to Figure 8 and Fig. 9 , Figure 8 This is a simplified structural diagram of another implementation method of the fixing unit provided in the embodiment of the present application. Fig. 9 for Figure 8 Diagram of the state of the fixing unit when used with different recording media.

[0083] In other implementations, such as Figure 8 As shown, the fixing unit 127 may further include a medium source 3 and a connecting pipe 4, and the connecting pipe 4 may connect the medium source 3 and the communicating channel 211, so as to achieve real-time injection or real-time extraction of the flowable medium 221 in the pressure-bearing part 22. In this way, the elastic performance of the pressure-bearing part 22 may be adjusted online, so that recording media P of different thicknesses can be compatible for fixing printing, and the compatibility of the fixing unit 127 can be improved.

[0084] In the related art, such as the hp150 printer, it is only compatible with the paper within the thickness range of 70gsm-160gsm for printing. However, after adopting the fixing unit 127 provided in the embodiment of the present application, the printing device 100 can at least be compatible with the printing of paper within the thickness range of 50gsm-220gsm, and the compatibility can be greatly improved.

[0085] The medium source 3 may also be different depending on the type of the flowable medium 221. For example, when the flowable medium 221 is a gas, the medium source 3 may be a gas source in the form of a gas cylinder or an air bag; when the flowable medium 221 is a liquid, the medium source 3 may be a liquid source in the form of a liquid tank. In order to reduce the occurrence of blockage problems, in this implementation, the flowable medium 221 preferably uses a fluid medium in the form of gas, liquid, etc.; of course, if the volume of the printing device 100 is relatively large, the flow area of ​​the corresponding connecting channel 211 and other pipelines is relatively large, and the risk of blockage is relatively low, and the flowable medium 221 may also use a bulk material.

[0086] The connecting pipeline 4 may be provided with pipeline components such as connecting pipes, switch valves, and driving pumps, so as to realize the pumping of the flowable medium 221. Fig. 9 When the recording medium P is thin paper P1, the switch valve and the driving pump can be controlled to start, so that the flowable medium 221 can be pumped from the medium source 3 into the pressure-bearing part 22 to increase the internal pressure of the pressure-bearing part 22; when the recording medium P is thick paper P2, the switch valve and the driving pump can be controlled to start, so that the flowable medium 221 can flow from the pressure-bearing part 22 to the medium source 3 to reduce the internal pressure of the pressure-bearing part 22.

[0087] Please refer to Figure 10-Figure 14 , Fig.10 This is a three-dimensional diagram of a fixing unit provided in an embodiment of the present application in one implementation mode. Fig.11 for Fig.10 A cross-sectional view perpendicular to the axial direction, Fig.12 for Fig.10 The front view of Fig.13 for Fig.10 Axial cross-section diagram, Fig.14 for Fig.10 Schematic diagram of the structure of the heating roller.

[0088] In a specific implementation, Fig.11 As shown, in the heating roller 1, the outer wall surface of the roller 11 may also be provided with a first anti-sticking layer 111. The first anti-sticking layer 111 may specifically be polytetrafluoroethylene (PTFE) or the like, and is used to reduce the adhesion of the melted developer Q to the roller 11 during the fixing process.

[0089] Similarly, the outer wall surface of the capsule skin 222 may also be provided with a second anti-sticking layer 222a, which may also be used to reduce the adhesion of the developer Q, etc. The material of the second anti-sticking layer 222a may be PTFE, soluble polytetrafluoroethylene (Polyfluoroalkoxy, PFA), etc. During specific manufacturing, FTFE or PFA may be powdered on the outer wall surface of the capsule skin 222, and then dried to form the above-mentioned second anti-sticking layer 222a.

[0090] Combined with 10, Figure 12-14 , first supports 13 are provided at both axial ends of the roller 11, and the first supports 13 can be support members in the form of bearings, bushings, sleeves, etc., for supporting the roller 11 during operation. Similarly, second supports 23 can also be provided at both axial ends of the mandrel 21, and the second supports 23 can also be support members in the form of bearings, bushings, sleeves, etc., for supporting the mandrel 21.

[0091] The axial end of the roller 11 may also be provided with a transmission component 14, which may specifically be a transmission element in the form of a gear, a pulley, a sprocket, or the like. The transmission component 14 may be connected to an external drive unit (not shown) in the form of a motor, etc., in order to introduce a driving force, thereby driving the roller 11 to rotate. The installation method of the transmission component 14 on the roller 11 is not limited herein. In actual applications, those skilled in the art may select it according to specific needs, as long as it can meet the requirements of use. For example, the transmission component 14 may be installed on the roller 11 by means of interference fit, spline connection, or the like; or, Fig.14 In the implementation method, the roller 11 can be provided with a notch groove 112, and the transmission component 14 can be provided with a clamping portion (not shown in the figure), and the transmission component 14 can be clamped in the notch groove 112 through the clamping portion. In this way, when the transmission component 14 rotates, the roller 11 can be driven to rotate through the cooperation between the outer wall surface of the clamping portion and the inner wall surface of the notch groove 112.

[0092] One end of the mandrel 21 may also be provided with a joint 212, which is used to connect to the connecting pipeline 4. According to the difference in the structural form of the connecting pipeline 4, the joint 212 may be replaced to match the interface difference between the mandrel 21 and the connecting pipeline 4.

[0093] It should be understood that the above-mentioned joint 212 is not a component that must be set. For a solution in which the connecting pipeline 4 and the core shaft 21 can be directly connected, the above-mentioned joint 212 may not be set; in addition, for a solution that does not require the amount of the flowable medium 221 in the pressure-bearing part 22 to be adjusted, the above-mentioned joint 212 may also be replaced by a plug to achieve the blocking of the connecting channel 211, so that the fixing unit 127 can be independently operated under the condition of no connecting pipeline 4 and medium source 3.

[0094] Please refer to Fig.15 , Fig.15 It is a structural schematic diagram of another implementation method of the pressure roller in the embodiment of the present application.

[0095] Different from the above Figure 5-Figure 14 In the implementation method, this implementation method provides another pressure-bearing part 22.

[0096] Specifically, Fig.15 As shown, the pressure-bearing part 22 may also include an annular capsule 223, and the capsule 223 may be directly mounted on the core shaft 21. In this implementation, the capsule 223 itself may form an installation chamber for accommodating the flowable medium 221, and a corresponding extraction port may be provided on the capsule 223 to realize the extraction of the flowable medium 221, without processing the connecting channel 211 on the core shaft 21, and the processing and preparation of the entire pressure-bearing roller 2 may be relatively simple.

[0097] The capsule 223 can be mounted on the mandrel 21 by bonding. Alternatively, a stopper in the form of a shoulder or the like can be provided on the mandrel 21 to stop the capsule 223 in the axial direction through the stopper, so that the capsule 223 can be mounted and fixed on the mandrel 21.

[0098] Please refer to Fig.16 , Fig.16 It is a structural schematic diagram of another implementation method of the heating roller in the embodiment of the present application.

[0099] Different from the above Figure 5-Figure 15 In the implementation method, this implementation method provides another heating roller 1.

[0100] Specifically, Fig.16As shown, the heating roller 1 may include a fixing film 15, a second heater 16 and a bracket 17; the second heater 16 and the bracket 17 may be arranged inside the fixing film 15, and the second heater 16 may be installed with the bracket 17; the second heater 16 may be specifically in the form of a plate, such as a ceramic heating plate, etc.; the second heater 16 and the bracket 17 may be displaced inside the fixing film 15, so as to compress the fixing film 15 through the second heater 16, and then compress the pressure-bearing portion 22. Since the second heater 16 is in the form of a plate, when the pressure-bearing portion 22 is pressed by the second heater 16, a substantially planar elastic clamping area 22a may be formed, so that the bending deformation of the recording material P may be reduced.

[0101] In this embodiment, the heating roller 1 may also be provided with a driving member (not shown in the figure), which may be connected to the bracket 17 in a transmission manner to drive the bracket 17 to perform a linear displacement, thereby driving the second heater 16 to perform a linear displacement; the driving member may be arranged on the inner side of the fixing film 15 or on the outer side of the fixing film 15. The driving member may be a driving element that can directly output a linear displacement, such as a cylinder or a hydraulic cylinder; or the driving member may be a driving element in the form of a motor, etc. In this case, the driving member may also include a displacement conversion mechanism in the form of a gear rack mechanism, a lead screw mechanism, etc., so as to convert the rotational displacement output by the motor into the linear displacement required by the bracket 17.

[0102] Specific examples are used herein to illustrate the principles and implementation methods of the present application, and the description of the above embodiments is only used to help understand the method and core ideas of the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A fixing unit, characterized in that: include: Heating rollers; The pressure-bearing roller comprises a core shaft and a deformable pressure-bearing portion, wherein the pressure-bearing portion is located radially outside the core shaft and is filled with a flowable medium.

2. The fixing unit according to claim 1, characterized in that: The pressure-bearing part includes a cylindrical bladder skin, the bladder skin outer shell is assembled on the core shaft, the axial ends of the bladder skin are respectively fixed to the core shaft, the bladder skin and the core shaft enclose a mounting chamber, and the flowable medium is filled in the mounting chamber.

3. The fixing unit according to claim 1, characterized in that: The pressure-bearing part comprises a ring-shaped capsule, and the capsule outer sleeve is assembled on the core shaft.

4. The fixing unit according to any one of claims 1 to 3, characterized in that: The flowable medium is a fluid medium or a bulk material.

5. The fixing unit according to any one of claims 1 to 4, characterized in that: The flowable medium is a fluid medium, the core shaft is provided with a connecting channel, the fixing unit also includes a medium source, the medium source is configured with a connecting pipeline, the connecting pipeline is connected to the connecting channel, and the fluid medium can flow into the pressure-bearing part through the connecting pipeline and the connecting channel, or flow out of the pressure-bearing part.

6. The fixing unit according to claim 5, characterized in that: The core shaft is provided with a joint, and the joint is connected to the connecting pipeline.

7. The fixing unit according to any one of claims 1 to 6, characterized in that: The outer wall surface of the pressure-bearing part is provided with a second anti-sticking layer.

8. The fixing unit according to any one of claims 1 to 7, characterized in that: The heating roller includes a roller and a first heater, at least a portion of the first heater is located inside the roller, and the heating roller presses the pressure roller through the roller.

9. The fixing unit according to any one of claims 1 to 7, characterized in that: The heating roller includes a fixing film and a second heater, the fixing film is cylindrical, the second heater is plate-shaped, the second heater is located inside the fixing film, the second heater can be displaced inside the fixing film, the second heater can abut the fixing film with one of its plate surfaces, and can pressurize the pressure roller through the fixing film.

10. A printing device, characterized in that: The invention comprises a shell and a fixing unit, wherein the fixing unit is the fixing unit according to any one of claims 1 to 9.

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