Plunger pump for low-viscosity medium

Abstract

The utility model relates to the technical field of hydraulic pressure, and discloses a plunger pump for a low-viscosity medium, which comprises a pump shell, a cylinder body, a rear cover, a transmission shaft, a swash plate, a plunger and a sliding shoe, the swash plate is fixed to the pump shell, plunger cavities and oil passing ports communicated with the plunger cavities are formed in the circumference of the cylinder body, one ends of the plungers are hinged to the sliding shoes, and the other ends of the plungers are arranged in the plunger cavities in a sliding mode. The piston shoe abuts against the swash plate, the cylinder body rotates to pass through the oil passing port to be communicated with the oil distribution window on the rear cover, the cylinder body is composed of a first metal framework, the two end faces of the cylinder body, the inner wall of the plunger cavity and the inner wall of the oil passing port are all provided with first injection molding layers, and the first injection molding layers are matched with the end faces of the cylinder body and the plunger cavity in shape. According to the scheme, the cylinder body adopts the metal framework so as to ensure that parts cannot generate large deformation under high pressure; by adopting an injection molding wrapping method, the friction part is completely wrapped by plastic, the friction is reduced by utilizing the lubricity of the plastic, and higher mechanical efficiency and volumetric efficiency can be realized at the same time.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulics, in particular to a plunger pump used for low-viscosity media. Background Art

[0002] For low-viscosity media, typically pure water or seawater pumps, there are currently two types: one is a low-pressure water pump, in which the friction pair can be made of engineering plastics. Since plastics lubricate well in water, they can achieve higher mechanical efficiency. However, due to the low strength of plastics, deformation under pressure will cause a sharp drop in volumetric efficiency; the other is a high-pressure water pump, in which the friction pair is made of metal with a plating layer. This can avoid the problem of engineering plastics deforming under large stress and maintain a relatively high volumetric efficiency. However, this structure will result in lower mechanical efficiency due to the high friction coefficient. Utility Model Content

[0003] The utility model aims to provide a plunger pump for low-viscosity media, so as to solve the problem that current water pumps cannot maintain high volumetric efficiency and high mechanical efficiency at the same time.

[0004] To achieve the above-mentioned purpose, the utility model adopts the following technical solution: a plunger pump for low-viscosity media, comprising: a pump housing, a cylinder body, a rear cover, a transmission shaft, a swash plate, a plunger and a sliding shoe; the transmission shaft is rotatably arranged in the pump housing, the swash plate is fixed to the pump housing, a plurality of plunger cavities are provided on the circumference of the cylinder body, one end of the plunger is hinged to the sliding shoe, and the other end is slidably arranged in the plunger cavity; the sliding shoe abuts against the swash plate, a plurality of oil passages are provided on the circumference of the cylinder body, the oil passages are communicated with the plunger cavity, and the oil passages are arranged in a one-to-one correspondence with the plunger cavity, the cylinder body abuts against the inner side surface of the rear cover, and the oil passages are communicated with the oil distribution window on the rear cover during the rotation of the cylinder body, the cylinder body is composed of a first metal frame, and the end faces of both ends of the cylinder body, the inner wall of the plunger cavity and the inner wall of the oil passage are all provided with a first injection molded layer, and the shape of the first injection molded layer matches the shape of the cylinder body end face and the shape of the plunger cavity.

[0005] Preferably, the first injection molded layer of the end faces of the cylinder body, the inner wall of the plunger cavity, and the inner wall of the oil port are integrally molded. Integral molding is more convenient, and the first injection molded layers at both ends are used to limit the position of the middle injection molded layer, making the first metal skeleton and the first injection molded layer more tightly connected.

[0006] Preferably, the inner wall of the plunger cavity is provided with a first groove. Providing the first groove can increase the contact area between the first metal skeleton and the first injection-molded layer, thereby enhancing the strength and stability of the connection and reducing stress concentration at the connection. The first groove design can effectively prevent slippage between the first metal skeleton and the first injection-molded layer, especially when subjected to lateral force or vibration.

[0007] Preferably, the first groove is annular. The annular groove can make the connection surface more evenly stressed, reduce stress concentration, and help improve the reliability and durability of the connection.

[0008] Preferably, there is at least one first groove, and the first groove is evenly arranged along the axial direction of the plunger cavity. Multiple annular grooves can better disperse the force and improve the strength and stability of the overall connection.

[0009] Preferably, a second groove is provided on the end surface of the cylinder body near the oil port. Providing the second groove can increase the contact area between the first metal frame and the first injection-molded layer, thereby enhancing the strength and stability of the connection and reducing stress concentration at the connection. The second groove design can effectively prevent slippage between the first metal frame and the first injection-molded layer, especially when subjected to lateral force or vibration.

[0010] Preferably, there is at least one second groove, and the second groove is arranged along the radial direction of the cylinder body. Multiple grooves can better disperse the force and improve the strength and stability of the overall connection.

[0011] Preferably, the side surface and outer surface of the oil passage are both provided with a second groove.

[0012] Preferably, the shoe is constructed from a second metal frame, with a second injection-molded layer applied to the end surface where the shoe connects to the plunger, and a second injection-molded layer applied to the outer wall of the shoe. Using a metal frame and coating the outer surface of the metal frame with plastic prevents significant deformation under high pressure, while also utilizing the lubricity of the plastic to reduce friction within the metal frame.

[0013] Preferably, a third groove is provided at the connection surface between the sliding shoe and the second injection-molded layer. The third groove increases the contact area between the second metal frame and the second injection-molded layer, thereby enhancing the strength and stability of the connection and reducing stress concentration at the connection. The third groove design effectively prevents slippage between the second metal frame and the second injection-molded layer, especially when subjected to lateral force or vibration.

[0014] This solution adopts a metal skeleton to ensure that the parts will not produce large deformation under high pressure; it adopts the method of injection molding to wrap all the friction parts with plastic, and uses the lubricity of plastic to reduce friction. The utility model designs a cylinder body and sliding shoe with a special structure, which can achieve high mechanical efficiency and volumetric efficiency at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the cylinder structure of an embodiment of the present utility model.

[0016] Figure 2 It is a cross-sectional schematic diagram of a cylinder body according to an embodiment of the present utility model.

[0017] Figure 3 This is a schematic diagram of the sliding shoe structure of an embodiment of the present utility model.

[0018] Figure 4 Schematic cross-sectional view of a sliding shoe according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The following is further described in detail through specific implementation methods:

[0020] The reference numerals in the drawings of the specification include: first metal skeleton 1, plunger cavity 2, oil port 3, first injection layer 4, first groove 5, second groove 6, second metal skeleton 7, second injection layer 8, and third groove 9.

[0021] Example:

[0022] A plunger pump for low-viscosity media includes: a pump housing, a cylinder body, a rear cover, a transmission shaft, a swash plate, a plunger and a slipper. The transmission shaft is rotatably arranged in the pump housing, the swash plate is fixed on the pump housing, and a mounting cavity for mounting the transmission shaft is provided in the middle of the cylinder body. Specifically, a spline connection can be adopted between the transmission shaft and the mounting cavity. A plurality of plunger cavities 2 are provided on the circumference of the cylinder body, one end of the plunger is hinged to the slipper, and the other end is slidably arranged in the plunger cavity 2; the slipper abuts against the swash plate, and a plurality of oil ports 3 are provided on the circumference of the cylinder body, the oil ports 3 are connected to the plunger cavity 2, and the oil ports 3 are arranged in a one-to-one correspondence with the plunger cavity 2. The cylinder body abuts against the inner side surface of the rear cover. During the rotation of the cylinder body, the oil ports 3 are connected to the oil distribution window on the rear cover. The more detailed position connection relationship of the above-mentioned component structures has been recorded in the application number CN202322285988.8 document and will not be described in detail here.

[0023] As attached Figure 1 and attached Figure 2 As shown, the cylinder body is composed of a first metal skeleton 1, and the end faces of the cylinder body, the inner wall of the plunger cavity 2 and the inner wall of the oil port 3 are provided with a first injection layer 4. The shape of the first injection layer 4 matches the shape of the cylinder body end face and the shape of the plunger cavity 2. The plunger cavity 2 and the oil port 3 are respectively provided at both ends of the cylinder body. After the first injection layer 4 is connected to the first metal skeleton 1, the structural shape of the cylinder body is not changed.

[0024] The inner wall of the plunger cavity 2 is provided with a first groove 5. The provision of the first groove 5 increases the contact area between the first metal skeleton 1 and the first injection-molded layer 4, thereby enhancing the strength and stability of the connection and reducing stress concentration at the connection. The design of the first groove 5 effectively prevents slippage between the first metal skeleton 1 and the first injection-molded layer 4, especially when subjected to lateral forces or vibrations.

[0025] There is at least one first groove 5, which is evenly distributed axially along the plunger cavity 2. Multiple annular grooves can better disperse the force, improving the strength and stability of the overall connection. The first groove 5 is annular. The annular groove can make the force on the connection surface more uniform, reduce stress concentration, and help improve the reliability and durability of the connection. In this embodiment, four annular grooves are evenly distributed axially within the plunger cavity 2.

[0026] The first injection-molded layer 4, which forms the end faces of the cylinder body, the inner wall of the plunger cavity 2, and the inner wall of the oil port 3, is integrally molded. This integrated molding facilitates manufacturing, and the first injection-molded layers 4 at both ends serve to position the central injection-molded layer, ensuring a tighter connection between the first metal skeleton 1 and the first injection-molded layer 4. The first injection-molded layer 4 is made of engineering plastic, which lubricates well in water and achieves high mechanical efficiency.

[0027] A second groove 6 is provided on the end surface of the cylinder body near the oil port 3. The provision of the second groove 6 increases the contact area between the first metal skeleton 1 and the first injection-molded layer 4, thereby enhancing the strength and stability of the connection and reducing stress concentration at the connection. The design of the second groove 6 effectively prevents slippage between the first metal skeleton 1 and the first injection-molded layer 4, especially when subjected to lateral forces or vibrations.

[0028] Preferably, there is at least one second groove 6, and the second groove 6 is arranged along the radial direction of the cylinder body. Multiple grooves can better disperse the force and improve the strength and stability of the overall connection.

[0029] Preferably, the side and outer surfaces of the oil port 3 are both provided with a second groove 6, which is also an annular groove. Liquid will flow through the oil port 3, and the second groove 6 is provided on the side and outer surfaces of the oil port 3 to ensure the connection strength between the first metal skeleton 1 and the first injection layer 4 on both sides of the oil port 3.

[0030] As attached Figure 3 and attached Figure 4 As shown, the shoe is constructed from a second metal frame 7, with a second injection-molded layer 8 applied to the end surface where the shoe connects to the plunger, and also to the outer wall of the shoe. Using a metal frame and coating the outer surface of the metal frame with plastic prevents significant deformation under high pressure, while also utilizing the lubricity of the plastic to reduce friction within the metal frame. The second injection-molded layer 8 is composed of engineering plastic, which lubricates well in water, resulting in high mechanical efficiency.

[0031] A third groove 9 is provided at the connection surface between the sliding shoe and the second injection-molded layer 8. The third groove 9 increases the contact area between the second metal frame 7 and the second injection-molded layer 8, thereby enhancing the strength and stability of the connection and reducing stress concentration at the connection. The third groove 9 effectively prevents slippage between the second metal frame 7 and the second injection-molded layer 8, especially when subjected to lateral forces or vibrations.

[0032] This proposal designs a cylinder block and sliding shoe with a special structure. Both use a metal skeleton to form their structural shape to ensure that the parts will not undergo significant deformation under high pressure. The injection molding method is adopted to wrap all the friction parts with plastic, and the lubricity of the plastic is used to reduce friction, which can achieve higher mechanical efficiency and volumetric efficiency at the same time.

[0033] The above is only an embodiment of the present invention. The remaining components of the plunger pump can also adopt a metal skeleton and injection molding layer structure, which can be adjusted and improved according to actual conditions. The common knowledge such as the specific technical solutions and / or characteristics in the scheme are not described in detail here. It should be pointed out that for those skilled in the art, several variations and improvements can be made without departing from the technical solution of the present invention. In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be a connection between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The scope of protection claimed by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A plunger pump for low-viscosity media, comprising: Pump housing, cylinder block, rear cover, drive shaft, swash plate, plunger and slipper; The transmission shaft is rotatably arranged in the pump housing, the swash plate is fixed on the pump housing, a plurality of plunger cavities are provided on the circumference of the cylinder body, one end of the plunger is hinged to the sliding shoe, and the other end is slidably arranged in the plunger cavity; the sliding shoe abuts against the swash plate, and a plurality of oil ports are provided on the circumference of the cylinder body, the oil ports are communicated with the plunger cavity, and the oil ports and the plunger cavities are arranged in a one-to-one correspondence, the cylinder body abuts against the inner side surface of the rear cover, and the oil ports are communicated with the oil distribution window on the rear cover during the rotation of the cylinder body, and it is characterized in that: the cylinder body is composed of a first metal skeleton, and the end faces of the two ends of the cylinder body, the inner wall of the plunger cavity and the inner wall of the oil port are all provided with a first injection molding layer, and the shape of the first injection molding layer matches the shape of the cylinder end face and the shape of the plunger cavity.

2. A plunger pump for low-viscosity media according to claim 1, characterized in that: The end surfaces at both ends of the cylinder body, the inner wall of the plunger cavity and the first injection molding layer of the inner wall of the oil passage are integrally formed.

3. The plunger pump for low-viscosity media according to claim 1, characterized in that: The inner wall of the plunger cavity is provided with a first groove.

4. A plunger pump for low-viscosity media according to claim 3, characterized in that: The first groove is annular.

5. The plunger pump for low-viscosity media according to claim 4, characterized in that: There is at least one first groove, and the first grooves are evenly arranged along the axial direction of the plunger cavity.

6. The plunger pump for low-viscosity media according to claim 1, characterized in that: A second groove is provided on the end surface of the cylinder body close to the oil passage end.

7. The plunger pump for low-viscosity media according to claim 6, characterized in that: There is at least one second groove, and the second groove is arranged along the radial direction of the cylinder body.

8. The plunger pump for low-viscosity media according to claim 6, characterized in that: The side surface and outer surface of the oil passage are both provided with a second groove.

9. The plunger pump for low-viscosity media according to claim 1, characterized in that: The sliding shoe is composed of a second metal frame, and a second injection molding layer is provided on the inner wall and the outer wall of the sliding shoe.

10. The plunger pump for low-viscosity media according to claim 9, characterized in that: A third groove is provided on the connecting surface between the sliding shoe and the second injection molding layer.

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