Plunger pair testing device of plunger pump

Abstract

The utility model relates to the technical field of plunger pumps, in particular to a plunger pump plunger pair testing device, which comprises a testing box body, a cylinder body and a transmission shaft, the testing box body comprises a left box body and a right box body, the cylinder body is fixed on the left box body through a bolt, and the transmission shaft is rotatably connected in the right box body through a bearing. The end part of the transmission shaft extends into the left box body and is connected with a swash plate (8); a plunger is arranged in a plunger cavity of the cylinder body, a return spring is further arranged between the plunger and the cylinder body, and a plunger head of the plunger is always in contact with the swash plate through the return spring. A balance cylinder body is further arranged in the left box body, a balance plunger is arranged in the balance cylinder body, and the balance plunger and the plunger are oppositely arranged along the center point of the swash plate. According to the utility model, the cylinder body is fixed in the left box body, and the plunger is always contacted with the swash plate through the return spring to simulate the reciprocating motion of the plunger in the plunger cavity under the action of the swash plate and oil pressure, so that an environment is provided for the oil film test of the plunger pair.

Description

Technical Field

[0001] The present application relates to the technical field of plunger pumps, and in particular to a plunger pump plunger pair testing device. Background Art

[0002] The axial piston pump is the most technologically advanced power and actuator in the hydraulic system. It can convert mechanical energy into hydraulic energy and is the representative of positive displacement hydraulic pumps. It has the advantages of large flow, small volume, high working pressure, high volumetric efficiency, and easy variable realization. It plays an irreplaceable role in transmission fields such as aerospace, engineering machinery, and servo hydraulic systems.

[0003] There are multiple sets of friction pairs inside the axial piston pump, among which the oil film of the piston pair is crucial to the performance of the pump. However, the characteristic parameters of the oil film can only be obtained through actual measurement. Due to the compactness and complexity of the axial piston pump structure, testing the piston pair is relatively difficult. Utility Model Content

[0004] The utility model aims to provide a plunger pump plunger pair testing device, which can provide a reliable environment for plunger pair oil film testing while realizing the real movement law of the plunger.

[0005] A plunger pump plunger pair testing device comprises a test box, a cylinder body and a transmission shaft, wherein the test box comprises a left box and a right box, the cylinder body is fixed to the left box by bolts, the transmission shaft is rotatably connected in the right box by a bearing, the end of the transmission shaft extends into the left box and is connected to a swash plate; a plunger is arranged in the plunger cavity of the cylinder body, a return spring is also arranged between the plunger and the cylinder body, and the plunger head of the plunger is always in contact with the swash plate through the return spring.

[0006] Furthermore, the left box body also includes a balancing cylinder body, in which a balancing plunger is arranged, and the balancing plunger is arranged opposite to the plunger along the center point of the swash plate.

[0007] Furthermore, the swash plate is connected to a swash plate frame via a combined bearing, and the swash plate frame is connected to a transmission shaft in an adjustable angle.

[0008] Furthermore, the combined bearing includes a thrust ball bearing and a deep groove ball bearing.

[0009] Furthermore, a parallel side plate is provided on the back of the swash plate frame, a main bolt hole and two secondary bolt holes are provided on the parallel side plate, an insert plate is provided on the end of the transmission shaft, a second main bolt hole corresponding to the main bolt hole and multiple groups of second secondary bolt holes corresponding to the two secondary bolt holes are provided on the insert plate, and the secondary bolt holes are connected with bolts of different groups of second secondary bolt holes to adjust the angle of the swash plate frame.

[0010] Furthermore, a sensor is fixed on the cylinder body, and the sensor includes a pressure sensor and a temperature sensor.

[0011] Furthermore, a friction bushing is provided in the plunger cavity of the cylinder body, and the thickness of the friction bushing is 2 mm.

[0012] Furthermore, the testing device also includes an oil supply pump station, which supplies oil to the cylinder body and the balancing cylinder body.

[0013] Beneficial effects of the utility model:

[0014] The utility model fixes the cylinder body in the left box body, and the plunger is always in contact with the inclined plate through the return spring to simulate the reciprocating motion of the plunger in the plunger cavity under the action of the inclined plate and oil pressure, thereby providing an environment for the oil film test of the plunger pair.

[0015] The swash plate structure of a single plunger is subjected to uneven force. The utility model further arranges a balancing cylinder 4 and a balancing plunger in the left housing. The balancing plunger and the plunger are symmetrically arranged relative to the swash plate, thereby offsetting the roll force of the single plunger on the swash plate, so that the swash plate can always maintain force balance during rotation.

[0016] The swash plate of the utility model is rigidly connected to the transmission shaft 11 through a swash plate frame. By arranging parallel side plates on the back of the swash plate frame and arranging multiple groups of second secondary bolt holes at the end of the transmission shaft, the connection angle between the swash plate frame and the end of the transmission shaft can be adjusted, thereby realizing an oil film test environment under different swash plate inclination angles. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the structure of the utility model;

[0018] Figure 2 It is a schematic diagram of the connection structure between the swash plate and the transmission shaft;

[0019] In the figure:

[0020] Cylinder body 1, left box body 2, right box body 3, balance cylinder body 4, plunger 5, sensor 6, return spring 7, swash plate 8, thrust ball bearing 81, deep groove ball bearing 82, swash plate frame 9, main bolt hole 91, auxiliary bolt hole 92, parallel side plate 93, transmission shaft 11. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying 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 direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0023] Embodiment 1:

[0024] like Figure 1 As shown, this embodiment discloses a plunger pump plunger pair test device, including a box body composed of a right-left box body 2 and a right box body 3, a cylinder body 1 fixed in the left box body, and a transmission shaft 11 fixed in the right box body 3. The cylinder body 1 is an axial piston pump cylinder structure, which is provided with a plunger cavity for the reciprocating motion of the plunger 5, and an oil hole leading to the plunger cavity. During the test, the oil hole provides high-pressure liquid oil through an external oil supply pump station. When the plunger pump is working, the plunger reciprocates in the plunger cavity under the action of the swash plate. In order to simulate this scenario, it is necessary to solve the problem of continuous contact between the plunger and the swash plate. The utility model sets a return spring between the plunger head of the plunger 5 and the cylinder body 1. When the transmission shaft 11 drives the swash plate 8 to rotate at high speed, the plunger head always presses against the swash plate 8 under the action of the return spring. Although the friction pair between the swash plate 8 and the plunger head is different from that in the actual operation of the plunger pump (with the force of the return spring), this embodiment is intended to test the plunger pair in the plunger cavity, and the friction pair between the plunger head and the swash plate is not a problem to be considered in this embodiment. Through the above scheme, the plunger 5 reciprocates in the plunger cavity under the action of the high-pressure oil and the return spring 7, thereby truly simulating the plunger motion law of the axial plunger pump.

[0025] When the single plunger pump is running, the swash plate 8 is subjected to the force of a plunger 5, which will cause the entire swash plate assembly and the shaft system to be unbalanced. Long-term testing will cause damage to the connection structure of the swash plate 8. For this reason, a balancing cylinder 4 is set in the left housing 2. The balancing cylinder 4 includes a second plunger cavity. A balancing plunger is set in the second plunger cavity. The balancing plunger also uses the same structure as the plunger 5 and is in close contact with the surface of the swash plate 8. During the test, the external oil supply pump station simultaneously provides high-pressure liquid oil to the balancing cylinder 4 and the cylinder 1. The balancing plunger and the plunger 5 are symmetrically arranged relative to the center of the swash plate 8, thereby offsetting the roll force of the single plunger 5 on the swash plate, so that the swash plate is always in a force balance state when rotating.

[0026] Embodiment 2:

[0027] like Figure 2As shown, this embodiment provides a connection structure between the swash plate 8 and the transmission shaft 11 with adjustable angle. The swash plate 8 is connected to the transmission shaft 11 through the parallel side plates 93 on the back of the swash plate frame 9. Specifically, the parallel side plates 93 are two parallel mounting plates, and the two mounting plates are provided with a main bolt hole 91 and two auxiliary bolt holes 92 at the same position. Figure 1 The end of the transmission shaft 11 shown is provided with an insert plate that can be inserted into the middle of the parallel side plates 93. The insert plate is provided with a second main bolt hole corresponding to the position of the main bolt hole 91, and a plurality of second secondary bolt holes, wherein the number of the second secondary bolt holes is greater than the secondary bolt holes 92. When connecting, the main bolt hole 91 is fixed with the second main bolt hole, and then the second secondary bolt hole fixed by the secondary bolt hole 92 is selected, thereby realizing the angle adjustment of the swash plate frame 9.

[0028] The swash plate frame 9 and the swash plate 8 are connected by a combination bearing of a thrust ball bearing 81 and a deep groove ball bearing 82. Because the plunger pump shaft system structure is complex and the forces between the transmission parts are interrelated, the combined bearing can reduce the rigidity of the swash plate-shaft system assembly, increase the flexibility of the entire mechanism, and reduce the impact on the working state of the plunger.

[0029] When testing the plunger pair, the plunger 5 and the plunger cavity will continue to wear. To address this issue, a wear-resistant bushing is provided between the plunger 5 and the plunger cavity. When severe wear problems occur, there is no need to replace the larger cylinder body, only the bushing needs to be replaced. This also facilitates the testing of the plunger pair under different material pairings.

[0030] In addition to the above embodiments, the present application also includes other implementation methods. Any technical solutions formed by equivalent transformation or equivalent replacement should fall within the protection scope of the claims of the present utility model.

Claims

1. A plunger pump plunger pair testing device, characterized in that: The invention comprises a test box, a cylinder (1) and a transmission shaft (11), wherein the test box comprises a left box (2) and a right box (3), wherein the cylinder (1) is fixed to the left box (2) by bolts, and the transmission shaft (11) is rotatably connected to the right box (3) by a bearing, and the end of the transmission shaft (11) extends into the left box (2) and is connected to a swash plate (8); a plunger (5) is arranged in a plunger cavity of the cylinder (1), and a return spring (7) is arranged between the plunger (5) and the cylinder (1), and the plunger head of the plunger (5) is always in contact with the swash plate (8) through the return spring.

2. A plunger pump plunger pair testing device according to claim 1, characterized in that: The left box body (2) is further provided with a balancing cylinder body (4), a balancing plunger is provided in the balancing cylinder body (4), and the balancing plunger and the plunger (5) are arranged opposite to each other along the center point of the swash plate (8).

3. A plunger pump plunger pair testing device according to claim 1, characterized in that: The swash plate (8) is connected to a swash plate frame (9) via a combined bearing, and the swash plate frame (9) is connected to a transmission shaft (11) in an angle-adjustable manner.

4. A plunger pump plunger pair testing device according to claim 3, characterized in that: The combined bearing comprises a thrust ball bearing (81) and a deep groove ball bearing (82).

5. A plunger pump plunger pair testing device according to claim 3, characterized in that: The back of the swash plate frame (9) is provided with a parallel side plate (93), and the parallel side plate (93) is provided with a main bolt hole (91) and two auxiliary bolt holes (92). The end of the transmission shaft (11) is provided with an insert plate, and the insert plate is provided with a second main bolt hole corresponding to the main bolt hole (91), and a plurality of groups of second auxiliary bolt holes corresponding to the two auxiliary bolt holes (92). The auxiliary bolt holes (92) are connected with bolts of different groups of second auxiliary bolt holes to adjust the angle of the swash plate frame (9).

6. A plunger pump plunger pair testing device according to any one of claims 1 to 5, characterized in that: The cylinder body (1) is provided with a sensor (6), and the sensor (6) comprises a pressure sensor and a temperature sensor.

7. A plunger pump plunger pair testing device according to any one of claims 1 to 5, characterized in that: A friction bushing is arranged in the plunger cavity of the cylinder body (1), and the thickness of the friction bushing is 2 mm.

8. A plunger pump plunger pair testing device according to any one of claims 1 to 5, characterized in that: The testing device also includes an oil supply pump station, which supplies oil to the cylinder body (1) and the balancing cylinder body (4).

Images