Axial plunger pump cylinder body and machining method

Abstract

The invention discloses an axial plunger pump cylinder body and a machining method. The axial plunger pump cylinder body comprises a cylinder body base body, a cylinder body plunger hole channel is formed in the cylinder body base body, a copper alloy layer is arranged on the inner wall of the cylinder body plunger hole channel, a double-spiral flow channel is formed in the copper alloy layer, and a cylinder body semicircular bottom face is arranged at the bottom of the cylinder body base body. According to the axial plunger pump cylinder body and the machining method, the high-heat-conduction material is adopted for machining, meanwhile, the inner hole is covered with the copper alloy layer, and the axial plunger pump cylinder body has the self-lubricating performance and is matched with the copper alloy layer, and the heat dissipation performance is good. Due to the double-spiral flow channel structure in the hole channel, the oil flow resistance is reduced, and the abrasion and the leakage rate of a friction pair of the cylinder body and the plunger are reduced. The working efficiency of the plunger pump is improved, the energy loss is reduced, the heat dissipation performance is improved, and the service life is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of construction machinery, and specifically to an axial piston pump cylinder block and a processing method thereof. Background Art

[0002] The piston pump is a core component in the hydraulic system, and its performance directly affects the efficiency and stability of the system. As one of the key components of the piston pump, the cylinder block bears the reciprocating motion of the piston and realizes the compression and transportation of the liquid. The traditional cylinder block mechanism has large energy losses: the internal channels of the cylinder block and the piston form a friction pair, and the friction between the two causes serious energy losses; poor heat dissipation performance: the cylinder block is prone to high temperature during operation, affecting the stable performance and service life of the pump; relatively complex structure: the traditional cylinder block design is complex, and the manufacturing and maintenance costs are relatively high.

[0003] In the existing technology, the structure of the piston pump cylinder block is mainly that a copper hollow cylindrical bushing is embedded in the cylinder block piston channel through a press-fitting process. The copper bushing and the cylinder block piston channel are in interference fit, and the bushing is slowly pressed into the cylinder block piston channel by a channel press-fitting tooling and a press, which can reduce friction and wear. However, this structure has high processing requirements for the cylinder block piston channel, and its processing dimensions and roughness need to be strictly controlled; at the same time, the copper bushing is embedded inside the channel, and deformation may occur, resulting in a gap between the two. Once the oil cleanliness is not high, the fine abrasive particles in the oil are likely to enter the mating surface of the bushing and the channel. Prolonged wear may cause the copper bushing to fall off, reducing the service life and increasing the maintenance cost. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the above deficiencies of the prior art and provide an axial piston pump cylinder block and a processing method thereof with simple structure and good effect.

[0005] The present invention is implemented as follows: an axial piston pump cylinder block includes a cylinder block base body. The cylinder block base body is provided with a cylinder block piston channel. The inner wall of the cylinder block piston channel is provided with a copper alloy layer. The copper alloy layer is provided with a double helix flow channel. The bottom of the cylinder block base body is provided with a cylinder block semi-circular bottom surface.

[0006] Furthermore: the material of the cylinder block base body is high-strength cast aluminum alloy.

[0007] The material model of the cylinder block base body is ZL205A.

[0008] The outer surface of the cylinder block base body is provided with a ceramic layer with a thickness of 20 - 25 µm and a surface hardness greater than HV1200.

[0009] The material of the copper alloy layer is tin bronze, and the thickness of the copper alloy layer is 1.5 mm.

[0010] The double helical flow channel includes an upper helical flow channel and a lower helical flow channel. The upper helical flow channel and the lower helical flow channel are parallel to each other. The distance between the two helical flow channels is 2 mm. The helix angle of the helical flow channel is 25° - 35°. The cross-section of the flow channel is a semi-circular cross-section with a diameter of 0.3 - 0.6 mm. The number of turns of the helical flow channel is 2 - 4 turns.

[0011] The helix angle of the helical flow channel is 30°. The cross-section of the flow channel is a semi-circular cross-section with a diameter of 0.4 mm. The number of turns of the helical flow channel is 3 turns.

[0012] The helical direction of the double helical flow channel is the same as the rotation direction of the plunger.

[0013] A processing method for the cylinder block of an axial piston pump For the cylinder block matrix, heat treatment is carried out using T6, including solution treatment and artificial aging; The outer surface of the cylinder block matrix is subjected to micro-arc oxidation treatment under the conditions of a voltage of 450 V and a frequency of 500 Hz to generate a ceramic layer; For the copper alloy layer, a casting process is used to cover the inner wall of the plunger hole of the cylinder block; After the double helical flow channel is processed, fluid polishing treatment is carried out.

[0014] The surface roughness Ra of the double helical flow channel after processing is ≤ 0.2 µm.

[0015] The present invention has the following advantages: For the cylinder block and processing method of the axial piston pump of the present invention, high thermal conductivity materials are used for processing. At the same time, the inner hole is covered with a copper alloy layer, which has self-lubricating properties and good heat dissipation performance in cooperation with the copper alloy layer. The double helical flow channel structure inside the hole reduces the oil flow resistance, reduces the wear and leakage of the friction pair between the cylinder block and the plunger. The working efficiency of the piston pump is improved, energy loss is reduced, heat dissipation performance is improved, and service life is extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings, as part of the present invention, are used to provide a further understanding of the present invention. The schematic embodiments and descriptions of the present invention are used to explain the present invention, but do not constitute an improper limitation to the present invention. Obviously, the drawings in the following description are only some embodiments. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] In the drawings: Figure 1 is a cross-sectional view of the internal structure of the cylinder block of the present invention; Figure 2 is a cross-sectional view of the cast copper alloy layer of the present invention.

[0018] In the figure: 1. Cylinder block base body; 2. Cylinder block plunger hole; 3. Copper alloy layer, 301. Upper spiral flow channel, 302. Lower spiral flow channel; 4. Semi-circular bottom surface of the cylinder block.

[0019] It should be noted that these drawings and textual descriptions are not intended to limit the scope of the concept of the present invention in any way, but to illustrate the concept of the present invention to those skilled in the art by referring to specific embodiments. Detailed implementation manners

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0021] In the description of the present invention, it should be noted that the orientation or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0022] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] As Figures 1 to 2 shown, an axial piston pump cylinder block includes a cylinder block base body 1. A cylinder block plunger hole 2 is provided inside the cylinder block base body 1. A copper alloy layer 3 is provided on the inner wall of the cylinder block plunger hole 2. A double spiral flow channel is provided on the copper alloy layer 3. A semi-circular bottom surface 4 of the cylinder block is provided at the bottom of the cylinder block base body 1. The material of the cylinder block base body 1 is high-strength cast aluminum alloy. For the axial piston pump cylinder block of the present invention, the inside of the cylinder block plunger hole is covered with a copper alloy layer through a casting process. Elements such as lead are added to the copper alloy, which gradually releases and forms a lubricating film during the operation of the cylinder block plunger hole and the plunger, having self-lubricating performance; at the same time, the cylinder block is processed with a high thermal conductivity material and cooperates with the copper alloy layer to improve the heat dissipation efficiency; a double spiral flow channel structure is designed inside the cylinder block plunger hole to reduce the oil flow resistance, reduce the wear and leakage of the friction pair between the cylinder block and the plunger. By optimizing the cylinder block structure design, the present invention aims to improve the working efficiency of the piston pump, reduce energy loss, improve heat dissipation performance, and extend the service life.

[0024] As shown Figure 1 in the figure, an axial piston pump cylinder block, the material model of the cylinder block base body 1 is ZL205A. The cylinder block base body material of the present invention is selected as high-strength cast aluminum alloy, such as ZL205A, and is finally processed by T6 heat treatment, so that the cylinder block base body has good thermal conductivity and can improve the heat dissipation performance of the cylinder block.

[0025] As shown Figures 1 to 2 in the figure, an axial piston pump cylinder block, a ceramic layer is provided on the outer surface of the cylinder block base body 1, with a thickness of 20 - 25 µm and a surface hardness greater than HV1200. An Al2O3 ceramic layer with a thickness of 20 - 25 µm is also provided outside the cylinder block base body of the present invention. It has high hardness. After the surface of the cylinder block base body is hardened, it has good wear resistance and heat dissipation performance, can effectively improve the outermost layer strength of the cylinder block base body, effectively protects the cylinder block base body, and prevents deformation caused by bumps, thereby affecting the use performance of the cylinder block.

[0026] As shown Figures 1 to 2 in the figure, an axial piston pump cylinder block, the material of the copper alloy layer 3 is tin bronze, and the thickness of the copper alloy layer 3 is 1.5 mm. The inner wall of the cylinder block piston hole of the present invention is cast with a copper alloy layer using tin bronze (ZCuPb10Sn10). After casting, the thickness of the copper alloy layer is 1.5 mm. The material of the copper alloy layer has good lubrication performance and plays a good buffering and lubricating role during the operation of the cylinder block piston hole and the piston; the tin bronze is processed onto the inner wall of the cylinder block piston hole by a casting process. The processing method is simple and effective, ensuring good adhesion and uniform thickness between the copper alloy layer and the inner wall of the cylinder block piston hole; the thickness of the copper alloy layer is specifically 1.5 mm. This thickness of the copper alloy layer can better meet the use requirements, that is, ensure effective lubrication between the cylinder block piston hole and the piston, and at the same time prevent the assembly accuracy between the cylinder block piston hole and the piston from being affected due to the large thickness of the copper alloy layer.

[0027] As shown Figures 1 to 2 in the figure, an axial piston pump cylinder block, the double spiral flow channel includes an upper spiral flow channel 301 and a lower spiral flow channel 302. The upper spiral flow channel 301 and the lower spiral flow channel 302 are parallel to each other. The distance between the two spiral flow channels is 2 mm. The spiral angle of the spiral flow channel is 25° - 35°. The cross-section of the flow channel is a semi-circular cross-section with a diameter of 0.3 - 0.6 mm, and the number of turns of the spiral flow channel is 2 - 4 turns. The double spiral flow channel inside the cylinder block of the present invention is composed of two parallel single spiral flow channels, namely the upper spiral flow channel and the lower spiral flow channel. They have certain parameters to meet the use requirements and maximize the role of the double spiral flow channel.

[0028] As shown Figures 1 to 2An axial piston pump cylinder block as shown, the spiral angle of the spiral flow channel is 30°, the cross-section of the flow channel is a semi-circular cross-section with a diameter of 0.4 mm, and the number of turns of the spiral flow channel is 3 turns. The spiral directions of the double spiral flow channels are the same as the rotation direction of the plunger. The number of turns of the spiral flow channel in the present invention is 3 turns. It should be noted here that 3 turns refer to 3 turns for each of the upper and lower spiral flow channels. In addition, the spiral flow channel is set to a smaller size to avoid internal leakage of the piston pump caused by too large a flow channel size. It should be noted that after the spiral flow channel is machined on the cylinder block plunger hole, fluid polishing treatment is required, and the surface roughness Ra ≤ 0.2 µm.

[0029] A processing method for an axial piston pump cylinder block The cylinder block base 1 is heat-treated by T6, including solution treatment and artificial aging; specifically, the solution treatment is carried out in the way of 515°C × 8 h + water cooling, and the artificial aging is carried out in the way of 175°C × 6 h + air cooling; The outer surface of the cylinder block base 1 is subjected to micro-arc oxidation treatment under the conditions of a voltage of 450 V and a frequency of 500 Hz to generate a ceramic layer; The copper alloy layer 3 is covered on the inner wall of the cylinder block plunger hole 2 by a casting process; After the double spiral flow channel is processed, fluid polishing treatment is carried out, and the surface roughness Ra of the processed double spiral flow channel ≤ 0.2 µm.

[0030] For the axial piston pump cylinder block and the processing method of the present invention, the cylinder block is made of a high thermal conductivity aluminum alloy material, the surface is hardened, and the wear resistance and heat dissipation performance are good; a copper alloy layer is cast inside the cylinder block plunger hole, and a double spiral flow channel structure is designed inside the cylinder block plunger hole, which improves the lubrication performance between the cylinder block plunger hole and the plunger, improves the heat dissipation performance and extends the service life.

[0031] In the specification provided here, a large number of specific details are described. However, it can be understood that the embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures, and technologies are not shown in detail so as not to obscure the understanding of this specification.

[0032] In addition, those skilled in the art can understand that although some embodiments described herein include certain features contained in other embodiments rather than other features, the combination of features of different embodiments also means being within the protection scope of the present invention and forming different embodiments. For example, in the above embodiments, those skilled in the art can use them in combination according to the known technical solutions and the technical problems to be solved by this application.

[0033] The above are only the preferred embodiments of the present invention, and there is no limitation to the present invention in any form. Although the present invention has been disclosed as above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art of this patent can make some changes or modifications to equivalent embodiments with equivalent changes by using the technical content prompted above within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the present invention's solution.

Claims

1. An axial piston pump cylinder, characterized in that: The invention comprises a cylinder base (1), wherein a cylinder plunger hole (2) is provided in the cylinder base (1), a copper alloy layer (3) is provided on the inner wall of the cylinder plunger hole (2), a double helical flow channel is provided on the copper alloy layer (3), and a cylinder semicircular bottom surface (4) is provided at the bottom of the cylinder base (1).

2. An axial piston pump cylinder according to claim 1, characterized in that: The material of the cylinder body matrix (1) is a high-strength cast aluminum alloy.

3. An axial piston pump cylinder according to claim 2, characterized in that: The material model of the cylinder body base (1) is ZL205A.

4. An axial piston pump cylinder according to claim 1, characterized in that: The outer surface of the cylinder body substrate (1) is provided with a ceramic layer with a thickness of 20-25 μm and a surface hardness greater than HV1200.

5. The axial piston pump cylinder according to claim 1, characterized in that: The material of the copper alloy layer (3) is tin bronze, and the thickness of the copper alloy layer (3) is 1.5 mm.

6. An axial piston pump cylinder according to claim 1, characterized in that: The double spiral flow channel comprises an upper spiral flow channel (301) and a lower spiral flow channel (302); the upper spiral flow channel (301) and the lower spiral flow channel (302) are parallel to each other; the spacing between the two spiral flow channels is 2 mm; the spiral angle of the spiral flow channel is 25°-35°; the flow channel cross section is a semicircular cross section with a diameter of 0.3-0.6 mm; and the number of turns of the spiral flow channel is 2-4.

7. An axial piston pump cylinder according to claim 6, characterized in that: The spiral flow channel has a helix angle of 30°, a flow channel cross section of a semicircular cross section with a diameter of 0.4 mm, and the number of turns of the spiral flow channel is 3.

8. An axial piston pump cylinder according to claim 1, characterized in that: The spiral direction of the double-helix flow channel is the same as the rotation direction of the plunger.

9. A method for processing the axial piston pump cylinder body according to claim 1, characterized in that: The cylinder body (1) is heat treated with T6, including solution treatment and artificial aging; The outer surface of the cylinder body substrate (1) is subjected to micro-arc oxidation treatment at a voltage of 450 V and a frequency of 500 Hz to form a ceramic layer; The copper alloy layer (3) is formed by a melting and casting process to cover the inner wall of the cylinder plunger hole (2); The double helix flow channel is processed and then subjected to fluid polishing.

10. The method for machining an axial piston pump cylinder body according to claim 9, characterized in that: The surface roughness of the double helical flow channel after processing is Ra≤0.2µm.

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