Developing roller convenient for heat dissipation and used for laser printer

Abstract

The developing roller comprises a conductive shaft core, a heat dissipation transition layer, a conductive elastic layer and a surface heat dissipation developing layer, the conductive shaft core is of a hollow structure, and a main heat dissipation channel penetrating in the axial direction is formed in the conductive shaft core; according to the developing roller facilitating heat dissipation for the laser printer, the heat dissipation efficiency is extremely high, overheating aging is avoided, a complete heat dissipation system of surface dissipation, middle transmission and internal export is constructed, the heat dissipation area is increased through a surface net-shaped heat dissipation structure, the heat dissipation efficiency is improved, and the heat dissipation efficiency is improved. The heat dissipation transition layer rapidly transfers heat, and the hollow conductive shaft core and the heat dissipation fins at the two ends accelerate export of internal heat, so that friction heat and Joule heat generated in the working process of the developing roller can be rapidly dissipated, aging and deformation of parts caused by heat accumulation are avoided, and the service life of the developing roller is prolonged.

Description

Technical Field

[0001] This invention relates to the field of laser printer components and related products, specifically a developing roller for laser printers that facilitates heat dissipation. Background Technology

[0002] The developing roller is the core component of a laser printer, enabling toner transfer and image formation. Its working state directly determines the print quality. During continuous operation of a laser printer, the developing roller generates a large amount of frictional heat due to high-speed friction with the photosensitive drum and toner. At the same time, Joule heating is generated when current flows through its internal conductive structure. The combined effect of these two types of heat causes the overall temperature of the developing roller to rise. If the heat cannot be dissipated in time, it can lead to a series of problems.

[0003] Currently, the developing rollers used in conventional laser printers on the market generally suffer from heat dissipation design defects, mainly manifested in the following ways: First, the conductive shaft core is mostly a solid structure, or simply a hollow structure, lacking a dedicated heat dissipation channel, making it easy for heat to accumulate inside; Second, the functional layers (elastic layer, developing layer) are made of materials with poor thermal conductivity, making it difficult for heat to be efficiently transferred between layers, and there is no dedicated heat dissipation structure on the surface, so heat cannot be quickly dissipated to the outside; Third, there is a lack of heat dissipation transition structure, resulting in low heat transfer efficiency between the conductive shaft core and the conductive elastic layer, failing to form a complete heat dissipation path; Fourth, the end caps installed at both ends only serve a fixing function and have no auxiliary heat dissipation function, further limiting the heat dissipation effect. Summary of the Invention

[0004] The purpose of this invention is to provide a developing roller for laser printers that facilitates heat dissipation, in order to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a developing roller for a laser printer with convenient heat dissipation, comprising a conductive shaft core, a heat dissipation transition layer, a conductive elastic layer, and a surface heat dissipation developing layer. The conductive shaft core has a hollow structure with an axially penetrating main heat dissipation channel inside. A plurality of radial heat dissipation holes communicating with the main heat dissipation channel are uniformly opened on the outer peripheral wall of the conductive shaft core. The heat dissipation transition layer tightly covers the outer periphery of the conductive shaft core, the conductive elastic layer covers the outer periphery of the heat dissipation transition layer, and the surface heat dissipation developing layer covers the outer periphery of the conductive elastic layer.

[0006] The heat dissipation transition layer is made of a high thermal and electrical conductivity composite material. It has several axially extending auxiliary heat dissipation channels evenly distributed inside. One end of the auxiliary heat dissipation channel is connected to the radial heat dissipation hole, and the other end extends to the contact surface between the heat dissipation transition layer and the conductive elastic layer.

[0007] As a preferred embodiment of the present invention, the conductive elastic layer comprises silicone rubber, carbon black, and thermally conductive filler.

[0008] As a preferred embodiment of the present invention, the surface heat dissipation developing layer is made of thermally and electrically conductive polyurethane material, and a plurality of annular heat dissipation grooves are uniformly formed on its surface. The annular heat dissipation grooves are arranged along the circumference of the surface heat dissipation developing layer. The surface of the surface heat dissipation developing layer is also provided with a plurality of axial heat dissipation patterns. The axial heat dissipation patterns are arranged along the axial direction of the surface heat dissipation developing layer and intersect with the annular heat dissipation grooves to form a mesh heat dissipation structure.

[0009] As a preferred embodiment of the present invention, the conductive shaft core is provided with mounting end caps at both ends, the mounting end caps having ventilation holes communicating with the main heat dissipation channel, and heat dissipation fins being provided on the inner side of the mounting end caps, the heat dissipation fins extending into the main heat dissipation channel and being tightly fitted to the inner wall of the conductive shaft core.

[0010] As a preferred embodiment of the present invention, the conductive shaft is made of 6061 aluminum alloy.

[0011] Preferably, the heat dissipation transition layer is made of a graphite-copper powder-epoxy resin composite material.

[0012] As a preferred embodiment of the present invention, the thermally conductive filler contained in the conductive elastic layer is a mixture of flake-shaped boron nitride powder and aluminum powder.

[0013] As a preferred embodiment of the present invention, the mounting end cover is made of thermally conductive plastic, the heat dissipation fins are distributed in a ring array, and the surface of the heat dissipation fins is provided with tiny heat dissipation protrusions.

[0014] As a preferred embodiment of the present invention, the surface of the heat dissipation and development layer is further provided with a wear-resistant conductive coating, which is made of polyimide-graphene composite material.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] This laser printer developing roller, designed for efficient heat dissipation, boasts extremely high heat dissipation efficiency, preventing overheating and aging. It features a complete heat dissipation system that integrates surface dissipation, intermediate transfer, and internal exhaust. The surface mesh structure increases the heat dissipation area, the heat transfer transition layer rapidly transfers heat, and the hollow conductive shaft core and end-heat dissipation fins accelerate the exhaust of internal heat. This system can quickly dissipate the frictional and Joule heat generated during the developing roller's operation, preventing heat accumulation that could lead to component aging and deformation, and extending the developing roller's lifespan. Attached Figure Description

[0017] Fig. 1 This is a schematic diagram of the structure of a heat dissipation-friendly developing roller for a laser printer according to the present invention;

[0018] Fig. 2 This is a schematic diagram of the conductive shaft core structure of a developing roller for a laser printer, which facilitates heat dissipation, according to the present invention.

[0019] Fig. 3 This is a schematic diagram of the surface heat dissipation developing layer structure of a developing roller for a laser printer, which facilitates heat dissipation according to the present invention.

[0020] In the diagram: 1. Conductive shaft core; 2. Heat dissipation transition layer; 3. Conductive elastic layer; 4. Surface heat dissipation layer; 5. Main heat dissipation channel; 6. Radial heat dissipation hole; 7. Auxiliary heat dissipation channel; 8. Annular heat dissipation groove; 9. Axial heat dissipation texture; 10. Mounting end cap; 11. Ventilation hole; 12. Heat dissipation fins; 13. Wear-resistant conductive coating; 14. Micro heat dissipation protrusions. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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 the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] Please see Figs. 1-3 The present invention provides an embodiment of a developing roller for a laser printer that facilitates heat dissipation, comprising a conductive shaft core 1, a heat dissipation transition layer 2, a conductive elastic layer 3, and a surface heat dissipation developing layer 4, with each layer sequentially covering the other from the inside out, and working together to achieve the functions of conductivity, developing and heat dissipation.

[0025] The conductive shaft core 1 has a hollow structure with an axially penetrating main heat dissipation channel 5 inside. The main heat dissipation channel 5 provides the main outlet channel for the heat inside the developing roller, which can quickly dissipate the heat accumulated inside. Several radial heat dissipation holes 6 are evenly opened on the outer peripheral wall of the conductive shaft core 1, which are connected to the main heat dissipation channel 5. The radial heat dissipation holes 6 can guide the heat transferred from the heat dissipation transition layer 2 into the main heat dissipation channel 5, realizing the rapid conduction of heat. At the same time, the conductive shaft core 1, as the core support component of the developing roller, undertakes the functions of conduction and support, ensuring the overall structural stability of the developing roller.

[0026] The heat dissipation transition layer 2 tightly wraps around the outer periphery of the conductive shaft core 1, serving as a heat transfer and transition layer while ensuring the continuity of conductivity. The heat dissipation transition layer 2 is made of a high thermal and electrical conductivity composite material, which can quickly conduct the heat transferred from the outer layer to the conductive shaft core 1, preventing heat from accumulating between layers. Several axially extending auxiliary heat dissipation channels 7 are evenly distributed inside the auxiliary heat dissipation channel 7. One end of the auxiliary heat dissipation channel 7 is connected to the radial heat dissipation hole 6, and the other end extends to the contact surface between the heat dissipation transition layer 2 and the conductive elastic layer 3. This allows for the rapid collection of heat transferred from the conductive elastic layer 3 and the surface heat dissipation layer 4, which is then introduced into the main heat dissipation channel 5 through the radial heat dissipation hole 6, thereby improving the heat transfer efficiency.

[0027] The conductive elastic layer 3 covers the outer periphery of the heat dissipation transition layer 2, mainly playing the roles of conductivity, buffering and toner adsorption assistance, ensuring good contact between the developing roller and the photosensitive drum, and ensuring stable toner transfer; at the same time, the conductive elastic layer 3 has a certain thermal conductivity, which can conduct the heat transferred from the surface heat dissipation developing layer 4 to the heat dissipation transition layer 2, and participate in the overall heat dissipation process.

[0028] The surface heat dissipation developing layer 4 is wrapped around the outer periphery of the conductive elastic layer 3. It is the part that directly contacts the developing roller with the toner and the photosensitive drum, and undertakes the core functions of toner adsorption, transfer and developing. At the same time, it has good thermal conductivity, which can quickly dissipate the frictional heat and electrostatic heat generated during the operation to the outside, reduce heat accumulation and ensure developing accuracy.

[0029] Furthermore, the conductive elastic layer 3 comprises silicone rubber, carbon black, and thermally conductive filler. The silicone rubber has excellent elasticity and high temperature resistance, which can ensure good contact between the developing roller and the photosensitive drum. The carbon black is used to improve the conductivity of the conductive elastic layer 3 and ensure the stability of electrostatic adsorption of toner. The thermally conductive filler can enhance the thermal conductivity of the conductive elastic layer 3, accelerate heat transfer, and prevent heat from accumulating in the elastic layer.

[0030] Furthermore, the surface heat dissipation developing layer 4 is made of thermally and electrically conductive polyurethane material. This material has excellent thermal conductivity, electrical conductivity, and wear resistance, which can quickly dissipate surface heat while ensuring the developing function. Several annular heat dissipation grooves 8 are uniformly formed on its surface, and these grooves are arranged along the circumference of the surface heat dissipation developing layer 4. The surface of the surface heat dissipation developing layer 4 is also provided with several axial heat dissipation patterns 9, which are arranged along the axial direction of the layer and intersect with the annular heat dissipation grooves 8 to form a mesh heat dissipation structure. This mesh heat dissipation structure can significantly increase the heat dissipation area of ​​the surface heat dissipation developing layer 4, accelerate the dissipation of surface heat to the outside, and improve heat dissipation efficiency.

[0031] Furthermore, each end of the conductive shaft core 1 is provided with a mounting end cap 10. The mounting end cap 10 is used to install and fix the developing roller inside the laser printer, and at the same time, it seals the main heat dissipation channel 5 and assists in heat dissipation. The mounting end cap 10 is provided with a ventilation hole 11 that communicates with the main heat dissipation channel 5. The ventilation hole 11 allows the main heat dissipation channel 5 to circulate with the outside air, accelerating the dissipation of heat in the main heat dissipation channel 5. The inner side of the mounting end cap 10 is provided with heat dissipation fins 12. The heat dissipation fins 12 extend into the main heat dissipation channel 5 and are tightly fitted with the inner wall of the conductive shaft core 1. The heat dissipation fins 12 can increase the contact area with the air in the main heat dissipation channel 5, quickly absorb the heat from the inner wall of the conductive shaft core 1, and conduct it out through the ventilation hole 11, further improving the internal heat dissipation effect.

[0032] Furthermore, the conductive shaft core 1 is made of 6061 aluminum alloy. 6061 aluminum alloy has excellent thermal conductivity, electrical conductivity and mechanical strength, which can quickly dissipate heat, while ensuring the structural stability of the developing roller. It is also lightweight and easy to install and rotate.

[0033] Furthermore, the heat dissipation transition layer 2 is made of graphite-copper powder-epoxy resin composite material. Graphite and copper powder have extremely high thermal conductivity, which can significantly improve the heat transfer efficiency of the heat dissipation transition layer 2. Epoxy resin is used to bond graphite and copper powder, ensuring the structural integrity of the heat dissipation transition layer 2 and its adhesion to adjacent layers, while ensuring its electrical conductivity, so as to realize the synchronous transfer of heat and current.

[0034] Furthermore, the thermally conductive filler contained in the conductive elastic layer 3 is a mixture of flake-shaped boron nitride powder and aluminum powder. The flake-shaped boron nitride powder has excellent thermal conductivity and insulation properties, which can improve thermal conductivity while avoiding abnormal toner adsorption caused by excessive conductivity of the conductive elastic layer 3. The aluminum powder has good thermal conductivity and electrical conductivity. When combined with the flake-shaped boron nitride powder, it can achieve a balance between thermal conductivity and electrical conductivity, further improving the heat dissipation effect and stability of the conductive elastic layer 3.

[0035] Furthermore, the mounting end cap 10 is made of thermally conductive plastic, which has good thermal conductivity and lightweight advantages, and can quickly dissipate the heat absorbed by the heat dissipation fins 12. The heat dissipation fins 12 are arranged in a ring array, which allows the heat dissipation fins 12 to evenly absorb the heat in the main heat dissipation channel 5 and avoid local heat accumulation. The surface of the heat dissipation fins 12 is provided with tiny heat dissipation protrusions 14, which can further increase the heat dissipation area of ​​the heat dissipation fins 12, accelerate heat dissipation, and improve the auxiliary heat dissipation effect.

[0036] Furthermore, the surface of the heat dissipation developing layer 4 is also provided with a wear-resistant conductive coating 13. The wear-resistant conductive coating 13 is made of polyimide-graphene composite material. Polyimide has excellent wear resistance and high temperature resistance, which can extend the service life of the surface heat dissipation developing layer 4 and avoid damage caused by long-term friction. Graphene has excellent thermal conductivity and electrical conductivity, which can further improve the heat dissipation efficiency and electrical conductivity of the surface, ensure the stability of toner adsorption and transfer, and reduce surface heat accumulation.

[0037] The working principle of this heat-dissipating developing roller for laser printers is described in detail below:

[0038] Heat generation and transfer: When the developing roller is working, the surface heat dissipation developing layer 4 generates frictional heat by rubbing against the photosensitive drum and toner. At the same time, electrostatic action and current flow generate Joule heat. The heat first accumulates on the surface heat dissipation developing layer 4. The thermally and electrically conductive polyurethane material of the surface heat dissipation developing layer 4 quickly transfers the heat to the inner conductive elastic layer 3. Some of the heat is directly dissipated to the outside through the surface mesh heat dissipation structure (annular heat dissipation grooves 8 and axial heat dissipation patterns 9).

[0039] Intermediate heat conduction: The conductive elastic layer 3 rapidly transfers heat to the heat dissipation transition layer 2 through the internal thermally conductive filler (a mixture of flake-shaped boron nitride powder and aluminum powder); the heat dissipation transition layer 2 is made of graphite-copper powder-epoxy resin composite material, which has extremely high thermal conductivity. Its internal auxiliary heat dissipation channel 7 rapidly collects heat and introduces it into the main heat dissipation channel 5 inside the conductive shaft core 1 through the radial heat dissipation holes 6 on the outer periphery of the conductive shaft core 1.

[0040] Internal heat dissipation: The conductive shaft core 1 is made of 6061 aluminum alloy, which can quickly conduct heat in the main heat dissipation channel 5; the annular array heat dissipation fins 12 on the inner side of the end caps 10 installed at both ends are tightly attached to the inner wall of the conductive shaft core 1, absorbing the heat in the main heat dissipation channel 5, and then dissipating the heat to the outside air through the ventilation holes 11 on the end caps 10, so as to achieve rapid dissipation of internal heat.

[0041] Auxiliary protection and heat dissipation: The polyimide-graphene wear-resistant conductive coating 13 on the surface of the heat dissipation developing layer 4 not only improves wear resistance and conductivity, but also further assists in the dissipation of surface heat; the mounting end cap 10 is made of thermally conductive plastic, which can assist the heat dissipation fins 12 in dissipating heat, ensuring the efficient and stable operation of the entire heat dissipation system and preventing the developing roller from overheating.

[0042] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A heat-dissipating developing roller for a laser printer, comprising a conductive shaft core (1), a heat-dissipating transition layer (2), a conductive elastic layer (3), and a surface heat-dissipating developing layer (4), characterized in that: The conductive shaft core (1) is a hollow structure with an axially penetrating main heat dissipation channel (5) inside. A plurality of radial heat dissipation holes (6) communicating with the main heat dissipation channel (5) are uniformly opened on the outer peripheral wall of the conductive shaft core (1). The heat dissipation transition layer (2) tightly covers the outer periphery of the conductive shaft core (1), the conductive elastic layer (3) covers the outer periphery of the heat dissipation transition layer (2), and the surface heat dissipation development layer (4) covers the outer periphery of the conductive elastic layer (3). The heat dissipation transition layer (2) is made of a high thermal conductivity and electrical conductivity composite material. It has a number of axially extending auxiliary heat dissipation channels (7) evenly distributed inside. One end of the auxiliary heat dissipation channel (7) is connected to the radial heat dissipation hole (6), and the other end extends to the contact surface between the heat dissipation transition layer (2) and the conductive elastic layer (3).

2. The developing roller for a laser printer with easy heat dissipation according to claim 1, characterized in that: The conductive elastic layer (3) comprises silicone rubber, carbon black and thermally conductive filler.

3. The developing roller for a laser printer with easy heat dissipation according to claim 1, characterized in that: The surface heat dissipation developing layer (4) is made of thermally and electrically conductive polyurethane material, and a number of annular heat dissipation grooves (8) are uniformly opened on its surface. The annular heat dissipation grooves (8) are arranged along the circumference of the surface heat dissipation developing layer (4). The surface of the surface heat dissipation developing layer (4) is also provided with a number of axial heat dissipation patterns (9). The axial heat dissipation patterns (9) are arranged along the axial direction of the surface heat dissipation developing layer (4) and intersect with the annular heat dissipation grooves (8) to form a mesh heat dissipation structure.

4. A developing roller for a laser printer with easy heat dissipation according to claim 1, characterized in that: The conductive shaft core (1) is provided with mounting end caps (10) at both ends. The mounting end caps (10) are provided with ventilation holes (11) that communicate with the main heat dissipation channel (5). The inner side of the mounting end caps (10) is provided with heat dissipation fins (12). The heat dissipation fins (12) extend into the main heat dissipation channel (5) and are tightly attached to the inner wall of the conductive shaft core (1).

5. A developing roller for a laser printer with easy heat dissipation according to claim 1, characterized in that: The conductive shaft (1) is made of 6061 aluminum alloy.

6. A developing roller for a laser printer with easy heat dissipation according to claim 1, characterized in that: The heat dissipation transition layer (2) is made of graphite-copper powder-epoxy resin composite material.

7. A developing roller for a laser printer with easy heat dissipation according to claim 2, characterized in that: The thermally conductive filler contained in the conductive elastic layer (3) is a mixture of flake-shaped boron nitride powder and aluminum powder.

8. A heat-dissipating developing roller for a laser printer according to claim 4, characterized in that: The mounting end cap (10) is made of thermally conductive plastic, the heat dissipation fins (12) are arranged in a ring array, and the surface of the heat dissipation fins (12) is provided with tiny heat dissipation protrusions (14).

9. A developing roller for a laser printer with easy heat dissipation according to claim 1, characterized in that: The surface of the heat dissipation and development layer (4) is further provided with a wear-resistant conductive coating (13), which is made of polyimide-graphene composite material.

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