Plunger pair oil film testing device capable of realizing high and low pressure switching

Abstract

The invention discloses a plunger pair oil film testing device capable of realizing high and low pressure switching. The plunger pair oil film testing device comprises a swash plate, a cylinder body and a valve block, a plunger is arranged in a plunger cavity of the cylinder body; one end of the plunger is connected with the cylinder body, and the other end abuts against the swash plate; the valve block is connected with the cylinder body, an oil way is arranged in the valve block, and an oil outlet of the oil way is communicated with a plunger cavity of the cylinder body. An oil supply port and an oil discharge port are formed in the surface of the valve block, and both the oil supply port and the oil discharge port are communicated with the oil way; the oil way is divided into an oil inlet way and an oil outlet way, an oil inlet one-way valve is arranged on the oil inlet way, and an oil outlet one-way valve and a first overflow valve are arranged on the oil outlet way. According to the testing device, high-pressure and low-pressure switching can be carried out in the plunger cavity, and the accuracy of a testing result is improved.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic component testing, and more particularly to a plunger auxiliary oil film testing device capable of realizing high-low pressure switching. Background Art

[0002] As one of the three key friction pairs in the plunger pump, the plunger pair (plunger-cylinder assembly) is a key component to maintain the energy conversion function of the plunger pump, and its lubrication state directly restricts the working performance of the plunger pump. Therefore, conducting experimental research on the oil film characteristics of the plunger pair can lay the foundation for improving the overall performance and life of the plunger pump and meeting the high-speed and high-pressure development trend of the axial plunger pump.

[0003] At present, there are two main experimental research methods for plunger pairs: one is to build a single plunger experimental platform; the other is to modify the actual pump and carry out relevant oil film tests in the modified model pump. Due to the complex internal structure of the actual pump, the installation and signal transmission of the sensor are extremely difficult, so a single plunger experimental platform is often chosen. However, in the existing single plunger experimental platform, the plunger cavity is often directly supplied with oil through the oil supply pipe, resulting in the pressure in the plunger cavity being determined by the oil supply source, and there is generally no high and low pressure switching, which is inconsistent with the engineering conditions of the actual operation process of the plunger pump.

[0004] Therefore, it is an urgent problem for technical personnel in this field to develop a plunger auxiliary oil film testing device that can switch between high and low pressures and improve the accuracy of test results. Summary of the invention

[0005] In view of this, the present invention provides a plunger auxiliary oil film testing device capable of high and low pressure switching to improve the accuracy of the test results.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A plunger auxiliary oil film testing device capable of realizing high and low pressure switching, comprising:

[0008] Swash plate,

[0009] A cylinder body, wherein a plunger is arranged in a plunger cavity of the cylinder body; one end of the plunger is connected to the cylinder body, and the other end abuts against the swash plate;

[0010] A valve block, the valve block is connected to the cylinder body, and an oil circuit is arranged inside the valve block, and the oil outlet of the oil circuit is communicated with the plunger cavity of the cylinder body; an oil supply port and an oil discharge port are arranged on the surface of the valve block, and the oil supply port and the oil discharge port are both communicated with the oil circuit; the oil circuit is divided into an oil inlet circuit and an oil discharge circuit, the oil inlet circuit is provided with an oil inlet check valve, and the oil discharge circuit is provided with an oil discharge check valve and a first overflow valve.

[0011] The beneficial effect of adopting the above technical scheme is that, in the present invention, the swash plate rotates, and when the distance between the swash plate and the plunger becomes larger, the plunger is pushed out by the oil to make a linear motion outward. At this time, the oil inlet check valve opens, the oil discharge check valve closes, and the oil enters the cylinder body from the valve block, so that the plunger cavity is filled with oil. At this time, the plunger cavity is a low-pressure area, and the pressure depends on the pressure of the oil supply port; when the plunger is pushed back inward by the swash plate to make a linear motion, the oil inlet check valve closes, the oil discharge check valve opens, and the oil in the plunger cavity is pushed back to the valve block from the oil discharge check valve and discharged to the oil tank through the oil discharge pipe. At this time, the plunger cavity is a high-pressure area, and the pressure depends on the overflow pressure set by the first overflow valve; the pressure in the plunger cavity in the present invention can realize the high-low pressure switching process, so that the experimental working conditions are more in line with the actual engineering conditions of the pump, thereby ensuring that the test results are more accurate.

[0012] Preferably, the connection end between the plunger and the swash plate is provided with a plunger ball head, the plunger ball head is hinged with a sliding shoe, and the sliding shoe fits the surface of the swash plate. The hinged connection between the plunger ball head and the sliding shoe can cooperate with the rotation of the swash plate to ensure that the sliding shoe always fits the swash plate.

[0013] Preferably, the plunger is placed in a bushing of the cylinder body and performs linear reciprocating motion along the bushing.

[0014] Preferably, a second overflow valve is further provided on the oil discharge oil circuit, and the first overflow valve and the second overflow valve are arranged in parallel. The second overflow valve can ensure that the oil can still be discharged normally when the first overflow valve fails to discharge the oil.

[0015] Preferably, a pressure measuring oil port is provided on the surface of the valve block, and the pressure measuring oil port is connected to the oil outlet end of the oil inlet circuit.

[0016] Preferably, a pressure sensor is connected to the pressure measuring oil port, and the pressure sensor can detect the pressure in the plunger cavity.

[0017] Preferably, an auxiliary cylinder is disposed outside the cylinder body, an auxiliary plunger is disposed inside the auxiliary cylinder body, the auxiliary plunger is hinged to the swash plate, and the plunger and the auxiliary plunger are symmetrically arranged on both sides of the swash plate. The auxiliary plunger can play the role of auxiliary support to ensure the balance of force during the rotation of the swash plate.

[0018] Preferably, an auxiliary oil supply port is provided on the surface of the valve block, the auxiliary oil supply port is communicated with the oil inlet circuit, and the auxiliary oil supply port is communicated with the plunger cavity of the auxiliary cylinder body through an auxiliary pipeline.

[0019] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a plunger auxiliary oil film testing device capable of realizing high and low pressure switching, and its beneficial effects are:

[0020] (1) In the present invention, the pressure in the plunger chamber of the plunger pump changes with the rotation period of the swash plate through the cooperation of the oil inlet check valve, the oil discharge check valve and the first relief valve, thereby generating a high-low pressure switching process, thereby solving the problem of the unchanged plunger chamber pressure of the single plunger test platform;

[0021] (2) The experimental working conditions of the test device in the present invention are more in line with the actual engineering conditions of the pump, so that the parameters such as the plunger auxiliary oil film pressure, thickness and temperature obtained subsequently are more accurate and more convincing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0023] Figure 1 A schematic diagram of the structure of the testing device provided by the present invention;

[0024] Figure 2 A top view of the testing device provided by the present invention;

[0025] Figure 3 A schematic diagram of the structure of the front side of the valve block provided by the present invention;

[0026] Figure 4 A schematic diagram of the structure of the back side of the valve block provided by the present invention;

[0027] Figure 5 A hydraulic principle diagram of the testing device provided by the present invention.

[0028] Among them, in the figure,

[0029] 1- swash plate; 2- cylinder block; 3- plunger;

[0030] 4-valve block;

[0031] 41- oil supply port; 42- oil discharge port; 43- oil inlet circuit; 44- oil discharge circuit; 45- oil inlet check valve; 46- oil discharge check valve; 47- first overflow valve; 48- second overflow valve; 49- auxiliary oil supply port;

[0032] 5- plunger ball head; 6- sliding shoe; 7- pressure sensor; 8- auxiliary cylinder; 9- auxiliary plunger; 10- auxiliary pipeline. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The embodiment of the present invention discloses a plunger auxiliary oil film testing device capable of realizing high and low pressure switching, comprising:

[0035] Swash plate 1,

[0036] A cylinder body 2, a plunger 3 is arranged in the plunger cavity of the cylinder body 2; one end of the plunger 3 is connected to the cylinder body 2, and the other end abuts against the swash plate 1;

[0037] The valve block 4 is connected to the cylinder body 2, and an oil circuit is arranged inside the valve block 4, and the oil outlet of the oil circuit is communicated with the plunger cavity of the cylinder body 2; the surface of the valve block 4 is provided with an oil supply port 41 and an oil discharge port 42, and the oil supply port 41 and the oil discharge port 42 are both communicated with the oil circuit; the oil circuit is divided into an oil inlet circuit 43 and an oil discharge circuit 44, and an oil inlet check valve 45 is arranged on the oil inlet circuit 43, and an oil discharge check valve 46 and a first overflow valve 47 are arranged on the oil discharge circuit 44.

[0038] In order to further optimize the above technical solution, the swash plate 1 is connected to a main shaft, and the swash plate 1 is driven to rotate by the rotation of the main shaft; the cylinder body 2 is fixed on the stand.

[0039] In order to further optimize the above technical solution, a plunger ball head 5 is provided at the connection end between the plunger 3 and the swash plate 1 , and the plunger ball head 5 is hinged with a sliding shoe 6 , which fits the surface of the swash plate 1 .

[0040] In order to further optimize the above technical solution, the plunger 3 is placed in the bushing of the cylinder body 2 and performs linear reciprocating motion along the bushing.

[0041] In order to further optimize the above technical solution, the oil tank is connected to the hydraulic pump through the motor to supply oil to the oil inlet circuit 44, and the oil discharged from the oil discharge line 44 will flow back into the oil tank.

[0042] In order to further optimize the above technical solution, a second overflow valve 48 is further provided on the oil discharge circuit 44, and the first overflow valve 47 and the second overflow valve 48 are arranged in parallel.

[0043] In order to further optimize the above technical solution, a pressure measuring oil port is opened on the surface of the valve block 4 , and the pressure measuring oil port is connected to the oil outlet end of the oil inlet oil circuit 43 .

[0044] In order to further optimize the above technical solution, a pressure sensor 7 is connected to the pressure measuring oil port.

[0045] In order to further optimize the above technical solution, an auxiliary cylinder body 8 is provided outside the cylinder body 2, and an auxiliary plunger 9 is provided inside the auxiliary cylinder body 8. The auxiliary plunger 9 abuts against the swash plate 1, and the plunger 3 and the auxiliary plunger 9 are symmetrically arranged on both sides of the swash plate 1.

[0046] In order to further optimize the above technical solution, an auxiliary oil supply port 49 is opened on the surface of the valve block 4, and the auxiliary oil supply port 49 is connected to the oil inlet circuit 43, and the auxiliary oil supply port 49 is connected to the plunger cavity of the auxiliary cylinder body 8 through the auxiliary pipeline 10.

[0047] Attached Figure 5 In the figure, P represents the oil supply port, T represents the oil drain port, P1 represents the oil outlet of the oil circuit, MP1 represents the pressure measuring port, and PQ represents the auxiliary oil supply port.

[0048] Working principle:

[0049] The oil enters the oil inlet circuit 43 and the auxiliary oil supply port 49 through the oil supply port 41, and the auxiliary oil supply port 4 is always connected to the oil supply port 41; an oil inlet check valve 45 is arranged in the valve block 4, and the plunger chamber oil supply port is connected to the oil inlet circuit 43 through the oil inlet check valve 45, and the oil enters the cylinder body 2 and the plunger chamber through the oil outlet P1. When the swash plate 1 rotates, the distance between the plunger 3 and the swash plate 1 becomes longer, and the plunger 3 moves outward under the push of the low-pressure oil in the plunger chamber until it is close to the surface of the swash plate 1. At this time, the plunger chamber is a low-pressure area, and the pressure is determined by the oil supply pressure; when the swash plate 1 rotates in the other half of the cycle, the plunger 3 is pushed back to the inside of the cylinder body 2 by the swash plate 1, and the oil returns to the oil discharge circuit 44 of the valve block 4, and flows from the oil discharge check valve 46 through the first relief valve 47. Since the oil is squeezed, the plunger chamber is a high-pressure area at this time, and the pressure depends on the opening pressure of the first relief valve 47. The valve block 4 is also provided with a pressure measuring port, which is connected to a pressure sensor 7, and the pressure sensor 7 is used to detect the plunger chamber pressure. The valve block 4 is also provided with a second relief valve 48, and the oil discharge oil circuit 44 where the second relief valve 48 is located is connected in parallel with the oil discharge oil circuit where the oil discharge check valve 46 and the first relief valve 47 are located, so that when the oil discharge oil circuits of the oil discharge check valve 46 and the first relief valve 47 fail, normal oil discharge can be ensured.

[0050] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0051] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A plunger auxiliary oil film testing device capable of realizing high and low pressure switching, characterized in that: include: Swash plate (1), A cylinder body (2), wherein a plunger (3) is arranged in a plunger cavity of the cylinder body (2); one end of the plunger (3) is connected to the cylinder body (2), and the other end is in contact with the swash plate (1); A valve block (4), the valve block (4) is connected to the cylinder body (2), and an oil circuit is arranged inside the valve block (4), and the oil outlet of the oil circuit is connected to the plunger cavity of the cylinder body (2); an oil supply port (41) and an oil discharge port (42) are arranged on the surface of the valve block (4), and the oil supply port (41) and the oil discharge port (42) are both connected to the oil circuit; the oil circuit is divided into an oil inlet circuit (43) and an oil discharge circuit (44), the oil inlet circuit (43) is provided with an oil inlet check valve (45), and the oil discharge circuit (44) is provided with an oil discharge check valve (46) and a first overflow valve (47).

2. A plunger auxiliary oil film testing device capable of realizing high and low pressure switching according to claim 1, characterized in that: The connection end between the plunger (3) and the swash plate (1) is provided with a plunger ball head (5), the plunger ball head (5) is hinged with a sliding shoe (6), and the sliding shoe (6) is in contact with the surface of the swash plate (1).

3. A plunger auxiliary oil film testing device capable of realizing high and low pressure switching according to claim 2, characterized in that: The plunger (3) is placed in the bushing of the cylinder body (2) and performs linear reciprocating motion along the bushing.

4. The plunger auxiliary oil film testing device capable of realizing high and low pressure switching according to claim 1, characterized in that: A second overflow valve (48) is also provided on the oil discharge circuit (44), and the first overflow valve (47) and the second overflow valve (48) are arranged in parallel.

5. The plunger auxiliary oil film testing device capable of realizing high and low pressure switching according to claim 1, characterized in that: A pressure measuring oil port is provided on the surface of the valve block (4), and the pressure measuring oil port is connected to the oil outlet end of the oil inlet circuit (43).

6. A plunger auxiliary oil film testing device capable of realizing high and low pressure switching according to claim 5, characterized in that: The pressure measuring oil port is connected to a pressure sensor (7).

7. The plunger auxiliary oil film testing device capable of realizing high and low pressure switching according to claim 1, characterized in that: An auxiliary cylinder body (8) is arranged outside the cylinder body (2), an auxiliary plunger (9) is arranged inside the auxiliary cylinder body (8), the auxiliary plunger (9) abuts against the swash plate (1), and the plunger (3) and the auxiliary plunger (9) are symmetrically arranged on both sides of the swash plate (1).

8. The plunger auxiliary oil film testing device capable of realizing high and low pressure switching according to claim 7, characterized in that: An auxiliary oil supply port (49) is provided on the surface of the valve block (4), the auxiliary oil supply port (49) is connected to the oil inlet circuit (43), and the auxiliary oil supply port (49) is connected to the plunger cavity of the auxiliary cylinder body (8) through an auxiliary pipeline (10).

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