Cylinder body assembly of hydraulic pump of excavator

By setting up a spiral oil groove on the inner wall of the copper sleeve, the oil pressure when the plunger pumps oil is used to transport oil into the oil groove to form oil film lubrication, which solves the wear problem caused by the oil pressure when the plunger pumps oil, and achieves a better lubrication effect and a wear reduction effect.

CN222615558UActive Publication Date: 2025-03-14WUXI MST TECH CO LTD
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Patent Information

Application Number
CN202421495638.2
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-06-27
Publication Date
2025-03-14
Estimated Expiration
2034-06-27

AI Technical Summary

Technical Problem

When the plunger pump is pumping oil, the plunger expands due to the oil pressure, which extrudes the lubricating oil, resulting in a lubricating oil film not being formed between the plunger and the copper sleeve, increasing wear.

Method used

A spiral-shaped first oil groove is arranged on the inner wall of the copper sleeve, and the opening end is arranged on one end face of the copper sleeve facing the bottom of the plunger hole. The copper sleeve does not completely cover the plunger hole, forming a gap for oil supply to pass. When the plunger pumps oil, the oil pressure is used to transport oil into the spiral-shaped first oil groove to form an oil film lubrication.

Benefits of technology

By forming an oil film lubrication, the friction between the plunger and the copper sleeve is reduced, wear is reduced, and the lubrication effect is enhanced.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model relates to the technical field of plunger pumps, in particular to an excavator hydraulic pump cylinder body assembly which comprises a cylinder body and a copper sleeve, the length of the copper sleeve is 2 / 3 of the depth of a plunger hole, the copper sleeve is located at the end, close to an opening, of the plunger hole, a first oil groove is formed in the inner wall of the copper sleeve, and a second oil groove is formed in the inner wall of the copper sleeve. The first oil groove is a spiral groove which is formed in the length direction of the first oil groove, one end of the spiral groove is open, the other end of the spiral groove is closed, and the open end of the first oil groove is arranged on the end face of the end, facing the bottom of the plunger hole, of the copper sleeve; when the plunger moves towards the bottom of the plunger hole to pump oil, the oil pressure is increased, and the oil enters the first oil groove through the opening of the first oil groove formed in the end face of the copper sleeve, so that when the plunger pumps the oil, the oil is conveyed into the spiral first oil groove through the oil pumping pressure, and when the plunger and the copper sleeve are in sliding friction, the oil is conveyed into the first oil groove. And an oil film can be formed between the plunger and the copper sleeve, so that the plunger and the copper sleeve are fully lubricated.
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Description

Technical Field

[0001] The utility model relates to the technical field of plunger pumps, in particular to an excavator hydraulic pump cylinder assembly. Background Art

[0002] Almost all the movements of the excavator are driven by the hydraulic system, and the core component of the hydraulic system is the hydraulic piston pump, which provides sufficient oil pressure for the entire hydraulic system. The hydraulic motor that drives the excavator forward and the hydraulic cylinder that drives the digging arm are all powered by the hydraulic piston pump, which is driven by the excavator's diesel engine.

[0003] Excavators all use axial piston pumps, which have the advantages of simple structure, small size, low noise, high efficiency, long life and self-priming ability. The plunger is connected to the inclined plate at a certain angle through a sliding shoe. As the cylinder body rotates, the plunger reciprocates in the plunger hole of the cylinder body, playing the role of sucking and pumping oil.

[0004] During the reciprocating motion of the plunger, the plunger will rub against the plunger hole of the cylinder body. By embedding a softer copper sleeve in the plunger hole, the friction can be reduced and the wear can be reduced. However, when the plunger is pumping oil, the oil pressure will cause the plunger to expand. The expanded plunger squeezes the copper sleeve, causing the lubricating oil between the plunger and the copper sleeve to be squeezed out, and it is difficult for external oil to enter between the plunger and the copper sleeve, resulting in a lubricating oil film that cannot be formed between the plunger and the copper sleeve, and then wear occurs. Utility Model Content

[0005] In view of the technical problems existing in the cylinder body in the prior art, the first aspect of the utility model proposes an excavator hydraulic pump cylinder body assembly, comprising:

[0006] A cylinder body, wherein a shaft hole for connecting with a rotating shaft is provided at the center of the cylinder body;

[0007] The cylinder body is provided with a plurality of plunger holes which are distributed in an annular pattern around the axial hole and are used for the plunger to reciprocate and absorb oil and pump oil, and an oil delivery hole for oil flow is provided between the bottom of the plunger hole and the end surface of the cylinder body;

[0008] Copper sleeves corresponding to the number of the plunger holes are respectively embedded in the plunger holes;

[0009] Wherein, the length of the copper sleeve is 2 / 3 of the depth of the plunger hole, and the copper sleeve is located at one end of the plunger hole close to the opening;

[0010] The inner wall of the copper sleeve is provided with a first oil groove, which is arranged to be a spiral groove opened along the length direction of the first oil groove and with one end open and the other end closed. The open end of the first oil groove is arranged on an end surface of the copper sleeve facing the bottom of the plunger hole, so that the oil in the plunger hole can enter the first oil groove along the end surface opening.

[0011] Preferably, the inner wall of the copper sleeve is provided with a second oil groove, and the second oil groove is arranged to be parallel to the path of the first oil groove and is a spiral groove with one end open and the other end closed. The open end of the second oil groove is arranged on an end surface of the copper sleeve facing the plunger hole opening, so that the shell oil can enter the second oil groove along the end surface opening.

[0012] Preferably, the number of spiral turns of the first oil groove and the second oil groove is at least one turn.

[0013] Preferably, the spiral length of the first oil groove and the second oil groove is at least 4 / 5 of the length of the copper sleeve.

[0014] Preferably, the depth of the first oil groove and the second oil groove is 1 / 2 of the thickness of the copper sleeve.

[0015] Preferably, the width of the first oil groove and the second oil groove is 1.0-3.0 mm.

[0016] Preferably, a flange for limiting the position of the copper sleeve is provided at one end of the copper sleeve facing the opening of the plunger hole.

[0017] Preferably, the outer wall of the copper sleeve is provided with an elastic sleeve for increasing the elastic restoring force of the copper sleeve.

[0018] Preferably, the elastic sleeve is made of nitrile rubber.

[0019] Preferably, the thickness of the elastic sleeve is at least 0.5 mm.

[0020] Compared with the prior art, the advantages of the utility model are:

[0021] A spiral first oil groove is arranged on the inner wall of the copper sleeve, the open end of the first oil groove is arranged on an end face of the copper sleeve facing the bottom of the plunger hole, the copper sleeve is arranged in the plunger hole, and the copper sleeve does not completely cover the plunger hole. Therefore, when the plunger slides in the copper sleeve, a gap for oil to pass through can be formed between the side wall of the bottom of the plunger hole and the plunger. When the plunger moves toward the bottom of the plunger hole to pump oil, the oil pressure in the gap increases, and the oil pressure acts on the end face of the copper sleeve and enters the first oil groove through the opening of the first oil groove opened on the end face of the copper sleeve. Therefore, whenever the plunger pumps oil, the oil pumping pressure is used to transport oil to the spiral first oil groove. When the plunger and the copper sleeve slide and rub, an oil film can be formed between the plunger and the copper sleeve, so that the plunger and the copper sleeve are fully lubricated and wear is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are not intended to be drawn to scale. In the accompanying drawings, each identical or nearly identical component shown in various figures may be represented by the same reference numeral. For the sake of clarity, not every component is labeled in each figure. Now, embodiments of various aspects of the utility model will be described by way of example and with reference to the accompanying drawings, in which:

[0023] Figure 1 It is a schematic diagram of the structure of the hydraulic pump cylinder assembly of an excavator shown in the utility model;

[0024] Figure 2 It is a cross-sectional view of a cylinder in an excavator hydraulic pump cylinder assembly shown in the utility model;

[0025] Figure 3 It is a structural schematic diagram of a copper sleeve in an excavator hydraulic pump cylinder assembly shown in the utility model;

[0026] Figure 4 It is a cross-sectional view of a copper sleeve in an excavator hydraulic pump cylinder assembly shown in the utility model.

[0027] 1. Cylinder body; 101. Shaft hole; 102. Plunger hole; 103. Oil delivery hole; 2. Copper sleeve; 21. Flange; 201. First oil groove; 202. Second oil groove; 3. Elastic sleeve. DETAILED DESCRIPTION

[0028] In order to better understand the technical content of the present invention, specific embodiments are described below in conjunction with the accompanying drawings.

[0029] Combination Figure 1-Figure 4 As shown, the utility model provides an excavator hydraulic pump cylinder assembly, comprising a cylinder 1 and a copper sleeve 2. The center of the cylinder 1 is provided with an axial hole 101 for connecting with a rotating shaft, and the cylinder 1 is driven to rotate by rotation;

[0030] The cylinder body 1 is provided with a plurality of plunger holes 102 distributed in an annular pattern around the axial hole 101. An oil delivery hole 103 for oil flow is provided between the bottom of the plunger hole 102 and the end surface of the cylinder body 1. The reciprocating motion of the plunger in the plunger hole 102 realizes the action of sucking and pumping oil.

[0031] Combination Figure 2 As shown, copper sleeves 2 corresponding to the number of plunger holes 102 are respectively embedded in the plunger holes 102. The copper sleeves 2 are soft in texture and have a small friction coefficient, which can reduce the wear of the reciprocating motion of the plunger.

[0032] However, when the plunger is pumping oil, the oil pressure will cause the plunger to expand. The expanded plunger squeezes the copper sleeve, causing the lubricating oil between the plunger and the copper sleeve to be squeezed out, and it is difficult for external oil to enter between the plunger and the copper sleeve, resulting in a lubricating oil film that cannot be formed between the plunger and the copper sleeve, which leads to increased wear.

[0033] Combination Figure 2 and Figure 3 As shown, the length of the copper sleeve 2 is 2 / 3 of the depth of the plunger hole 102, and the copper sleeve 2 is located at one end of the plunger hole 102 close to the opening;

[0034] The inner wall of the copper sleeve 2 is provided with a first oil groove 201, which is arranged to be a spiral groove opened along the length direction of the first oil groove 201 and closed at one end. The open end of the first oil groove 201 is arranged on an end surface of the copper sleeve 2 facing the bottom of the plunger hole 102. When the plunger pumps oil, the oil in the plunger hole 102 can enter the first oil groove 201 along the end surface opening.

[0035] It should be understood that since the copper sleeve 2 does not completely cover the plunger hole 102, when the plunger slides in the copper sleeve 2, a gap for oil to pass through can be formed between the bottom side wall of the plunger hole 102 and the plunger. When the plunger moves toward the bottom of the plunger hole 102 to pump oil, the oil pressure in the gap increases, and the oil pressure acts on the end face of the copper sleeve 2 and enters the first oil groove 201 through the opening of the first oil groove 201 opened on the end face of the copper sleeve 2.

[0036] In this way, whenever the plunger pumps oil, the pumping oil pressure is used to transport oil into the spiral first oil groove 201. When the plunger and the copper sleeve 2 slide and rub, an oil film can be formed between the plunger and the copper sleeve 2, so that the plunger and the copper sleeve 2 are fully lubricated and wear is reduced.

[0037] Furthermore, a second oil groove 202 is provided on the inner wall of the copper sleeve 2. The second oil groove 202 is arranged to be parallel to the path of the first oil groove 201 and is a spiral groove with one end open and the other end closed. The open end of the second oil groove 202 is arranged on an end face of the copper sleeve 2 that opens toward the plunger hole 102, so that the shell oil can enter the second oil groove 202 along the end face opening.

[0038] It should be understood that the open end of the second oil groove 202 is connected to the inside of the pump casing, and the oil in the pump casing can enter the second oil groove 202 along the open end of the second oil groove 202. When the plunger pump initially rotates, the oil pressure is small and cannot enter the first oil groove 201. The oil in the second oil groove 202 lubricates the plunger and the copper sleeve 2, reducing the wear of the plunger pump during initial rotation.

[0039] Combination Figure 3 and Figure 4 As shown, the number of spiral turns of the first oil groove 201 and the second oil groove 202 is at least one turn, so that the first oil groove 201 and the second oil groove 202 can cover a circle of the plunger, generate a lubricating oil film around the plunger, and improve the lubrication effect.

[0040] Furthermore, the spiral length of the first oil groove 201 and the second oil groove 202 is at least 4 / 5 of the length of the copper sleeve 2, which can cover the plunger along the length to the maximum extent and make the oil film distribution more uniform.

[0041] Furthermore, the depth of the first oil groove 201 and the second oil groove 202 is 1 / 2 of the thickness of the copper sleeve 2, and the width of the first oil groove 201 and the second oil groove 202 is 1.0-3.0 mm. Preferably, the width of the first oil groove 201 and the second oil groove 202 is 3.0 mm, so that the first oil groove 201 and the second oil groove 202 can store sufficient oil to fully lubricate the plunger and the copper sleeve 2.

[0042] Combination Figure 4 As shown, the outer wall of the copper sleeve 2 is provided with an elastic sleeve 3 for increasing the elastic restoring force of the copper sleeve 2. When the plunger pump oil expands and squeezes the copper sleeve 2, the copper sleeve 2 compresses the elastic sleeve 3 and can expand outward synchronously to reduce the friction between the copper sleeve 2 and the plunger. At the same time, when there is no oil pressure, the elastic sleeve 3 can shrink and recover the copper sleeve 2, fit and seal with the plunger to avoid permanent deformation of the copper sleeve 2. The thickness of the elastic sleeve 3 is at least 0.5 mm, so that the elastic sleeve 3 has sufficient elastic deformation distance.

[0043] In an optional embodiment, the elastic sleeve 3 is made of nitrile rubber, which not only has good elasticity but also has good oil resistance and can be used in an oil environment for a long time.

[0044] Combination Figure 3 As shown, the end of the copper sleeve 2 opening toward the plunger hole 102 is provided with a flange 21 for limiting the copper sleeve 2, and the open end of the plunger hole 102 is provided with a step groove corresponding to the flange 21. The flange 21 is embedded in the step groove and will not protrude from the surface of the cylinder body 1 to avoid interference.

[0045] In combination with the above embodiments, a spiral first oil groove 201 is provided on the inner wall of the copper sleeve 2, and the open end of the first oil groove 201 is provided on an end surface of the copper sleeve 2 facing the bottom of the plunger hole 102. The copper sleeve 2 is provided in the plunger hole 102, and the copper sleeve 2 does not completely cover the plunger hole 102. Therefore, when the plunger slides in the copper sleeve 2, a gap for oil to pass through can be formed between the side wall at the bottom of the plunger hole 102 and the plunger. When the plunger moves toward the bottom of the plunger hole 102 to pump oil, the oil pressure in the gap increases, and the oil pressure acts on the end surface of the copper sleeve 2, and enters the first oil groove 201 through the opening of the first oil groove 201 provided on the end surface of the copper sleeve 2;

[0046] In this way, whenever the plunger pumps oil, the pumping oil pressure is used to transport oil into the spiral first oil groove 201. When the plunger and the copper sleeve 2 slide and rub, an oil film can be formed between the plunger and the copper sleeve 2, so that the plunger and the copper sleeve 2 are fully lubricated and wear is reduced.

[0047] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. A person with ordinary knowledge in the technical field to which the present invention belongs may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the definition of the claims.

Claims

1. Excavator hydraulic pump cylinder assembly, characterized in that: include: A cylinder body (1), wherein a shaft hole (101) for connecting to a rotating shaft is provided at the center of the cylinder body (1); The cylinder body (1) is provided with a plurality of plunger holes (102) distributed in an annular pattern around the axial hole (101) and used for the plunger to reciprocate and absorb oil and pump oil, and an oil delivery hole (103) for oil flow is provided between the bottom of the plunger hole (102) and the end surface of the cylinder body (1); Copper sleeves (2) corresponding in number to the plunger holes (102) are respectively embedded in the plunger holes (102); The length of the copper sleeve (2) is 2 / 3 of the depth of the plunger hole (102), and the copper sleeve (2) is located at one end of the plunger hole (102) close to the opening; The inner wall of the copper sleeve (2) is provided with a first oil groove (201), and the first oil groove (201) is arranged as a spiral groove opened along the length direction of the first oil groove (201) and having one end open and the other end closed. The open end of the first oil groove (201) is arranged on an end surface of the copper sleeve (2) facing the bottom of the plunger hole (102), so that the oil in the plunger hole (102) can enter the first oil groove (201) along the end surface opening.

2. The excavator hydraulic pump cylinder assembly according to claim 1, characterized in that: The inner wall of the copper sleeve (2) is provided with a second oil groove (202), the second oil groove (202) being arranged to be parallel to the path of the first oil groove (201) and being a spiral groove with one end open and the other end closed, the open end of the second oil groove (202) being arranged on an end surface of the copper sleeve (2) that is open toward the plunger hole (102), so that the housing oil can enter the second oil groove (202) along the end surface opening.

3. The excavator hydraulic pump cylinder assembly according to claim 2, characterized in that: The number of spiral turns of the first oil groove (201) and the second oil groove (202) is at least one turn.

4. The excavator hydraulic pump cylinder assembly according to claim 2, characterized in that: The spiral length of the first oil groove (201) and the second oil groove (202) is at least 4 / 5 of the length of the copper sleeve (2).

5. The excavator hydraulic pump cylinder assembly according to claim 2, characterized in that: The depth of the first oil groove (201) and the second oil groove (202) is 1 / 2 of the thickness of the copper sleeve (2).

6. The excavator hydraulic pump cylinder assembly according to claim 2, characterized in that: The width of the first oil groove (201) and the second oil groove (202) is 1.0-3.0 mm.

7. The excavator hydraulic pump cylinder assembly according to claim 1, characterized in that: One end of the copper sleeve (2) that opens toward the plunger hole (102) is provided with a flange (21) for limiting the position of the copper sleeve (2).

8. The excavator hydraulic pump cylinder assembly according to claim 1, characterized in that: The outer wall of the copper sleeve (2) is provided with an elastic sleeve (3) for increasing the elastic restoring force of the copper sleeve (2).

9. The excavator hydraulic pump cylinder assembly according to claim 8, characterized in that: The elastic sleeve (3) is made of nitrile rubber.

10. The excavator hydraulic pump cylinder assembly according to claim 8, characterized in that: The thickness of the elastic sleeve (3) is at least 0.5 mm.