Low-abrasion pump core structure and excavator hydraulic pump
By setting up an oil storage tank and expansion ring on the plunger, the wear problem caused by insufficient lubrication in the plunger pump is solved, and the lubrication effect with low wear is achieved, and the service life of the equipment is extended.
Patent Information
- Application Number
- CN202421986756.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Priority Date
- 2024-05-09
- Filing Date
- 2024-08-16
- Publication Date
- 2025-07-29
- Estimated Expiration
- 2034-08-16
AI Technical Summary
In the existing excavator hydraulic plunger pump, the wear problem between the plunger and the cylinder block is serious, especially when the oil pressure in the plunger cavity increases, the lubricating oil is scraped away, resulting in insufficient lubrication and aggravation of wear.
An oil storage tank is installed on the plunger and an expansion ring is installed with thermal expansion. Lubricating oil is stored in the oil storage tank. The expansion ring increases the pressure in the oil storage tank under the action of thermal expansion and contraction. The lubricating oil forms an oil film during the plunger movement to reduce wear.
By forming an oil film on the plunger and the inner wall of the cylinder, it can effectively reduce wear, improve lubrication effect, and extend the service life of the equipment.
Smart Images
Figure CN223164691U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of plunger pumps, and particularly relates to a low-wear pump core structure and an excavator hydraulic pump. Background Art
[0002] Almost all actions of an excavator are driven by a hydraulic system, and the core component of the hydraulic system is a hydraulic plunger pump, which provides sufficient oil pressure for the entire hydraulic system. The hydraulic motor that drives the excavator to move forward and the hydraulic cylinder that drives the movement of the excavating arm are all powered by the hydraulic plunger pump, and the hydraulic plunger pump is driven by the diesel engine of the excavator.
[0003] Axial plunger pumps are used in excavators, which have the advantages of simple structure, small size, low noise, high efficiency, long service life, and self-priming ability. However, since the axial plunger pump uses the reciprocating movement of the plunger in the cylinder block to achieve oil suction - oil pumping, the plunger will rub against the inner wall of the cylinder block. Currently, the distribution disk and plunger of the plunger pump are made of high-hardness materials, while the cylinder block is made of softer gray cast iron, aluminum alloy, or copper alloy materials. The purpose is to avoid mutual scratching caused by the same hardness, which results in easy wear of the cylinder block when the high-hardness plunger reciprocates in the softer cylinder block.
[0004] In order to reduce wear, it is necessary to fully lubricate between the plunger and the cylinder block. The existing lubrication method is to apply lubricating oil in the fitting clearance between the plunger and the cylinder block to form a lubricating oil layer between the plunger and the cylinder block. However, in order to reduce weight, enhance cooling, and reduce thermal expansion of materials, the plungers of larger-sized excavator hydraulic pumps are often hollow structures. Therefore, during the oil pumping process of the plunger pump, the oil pressure in the inner cavity of the plunger increases, resulting in an increase in the bulging diameter of the plunger. At this time, the clearance between the plunger and the plunger cavity decreases. During the oil pumping process of the plunger pump, the oil on the inner wall of the plunger cavity will be scraped to one end by the end of the plunger, resulting in a reduction in the lubricating oil between the plunger and the inner wall of the plunger cavity and insufficient lubrication, which exacerbates wear. Summary of the Utility Model
[0005] In view of the technical problems existing in the plunger in the prior art, the first aspect of the present utility model proposes a low-wear pump core structure, including:
[0006] A cylinder block, on which a plurality of plunger cavities are circumferentially and evenly distributed;
[0007] Plungers corresponding to the number of the plunger cavities are respectively arranged in the plunger cavities, and the plungers are arranged to reciprocate in the plunger cavities;
[0008] Wherein, one end of the plunger located in the plunger cavity is provided with an oil storage groove. When the plunger is installed in the plunger cavity, the oil storage groove is enclosed by the plunger cavity to form a cavity for storing lubricating oil. An expansion ring that can expand when heated is sleeved in the oil storage groove to increase the pressure in the oil storage groove.
[0009] Preferably, the thickness of the expansion ring is 1 / 2 of the depth of the oil storage groove.
[0010] Preferably, the distance between the outer diameter of the expansion ring and the outer diameter of the oil storage groove is 2.0 - 3.0 mm.
[0011] Preferably, the expansion ring is made of rubber.
[0012] Preferably, the expansion ring is arranged in two symmetric semi - circular ring structures, and the width of the expansion ring is the same as the width of the oil storage groove.
[0013] Preferably, a support ring for maintaining its semi - circular ring shape is fixed on the inner side wall of the expansion ring, and the width of the support ring is the same as the width of the oil storage groove.
[0014] Preferably, a plurality of evenly distributed magnets are provided on the support ring to adsorb the worn - off magnetic metal particles.
[0015] In a second aspect of the present utility model, an excavator hydraulic pump is proposed, including:
[0016] A pump body, one end of the pump body is provided with a pump cover, and a transmission shaft is arranged inside the pump body;
[0017] The above - mentioned low - wear pump core structure, wherein the cylinder block in the pump core structure is arranged on the transmission shaft and rotates synchronously with the transmission shaft;
[0018] A distribution disk, arranged on the pump cover and in sliding contact with the first end of the cylinder block. An oil inlet cavity and an oil discharge cavity corresponding to the plunger cavity are provided on the distribution disk;
[0019] An inclined disk, located at the second end of the cylinder block, and the plunger is connected to the inclined disk;
[0020] Wherein, when the cylinder block rotates one week, the plunger reciprocates once in the plunger cavity.
[0021] Preferably, a skid is provided between the plunger and the inclined disk. A spherical seat connected to the skid is provided on the plunger, and the plunger is connected to the inclined disk through the skid.
[0022] Preferably, a control valve component for adjusting the inclination angle of the inclined disk is provided on the pump body to change the reciprocating stroke of the plunger.
[0023] Compared with the prior art, the advantages of the present utility model are as follows:
[0024] 1. By providing an oil storage groove on the plunger, when the plunger is installed in the plunger cavity, the oil storage groove is enclosed by the plunger cavity to form a cavity for storing lubricating oil. During the process of the plunger sliding in the oil pumping direction, the lubricating oil inside the oil storage groove can lubricate the area where the plunger contacts the inner wall of the plunger cavity, forming an oil film between the plunger and the inner wall of the plunger cavity, and reducing wear;
[0025] 2. An expansion ring that can expand when heated is sleeved inside the oil storage groove. During the reciprocating movement of the plunger for oil suction - oil pumping, heat will be generated by friction. When the expansion ring is heated, under the action of thermal expansion and contraction, the expansion ring expands, the internal space of the oil storage groove decreases, and the lubricating oil inside the oil storage groove is squeezed against the inner wall of the plunger cavity, improving the lubrication effect. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The drawings are not intended to be drawn to scale. In the drawings, each identical or approximately identical component shown in each figure may be denoted by the same reference numeral. For clarity, not every component is labeled in each figure. Now, embodiments of various aspects of the present utility model will be described by way of examples and with reference to the drawings, wherein:
[0027] Figure 1 is a schematic diagram of the low - wear pump core structure and the structure of an excavator hydraulic pump shown in the present utility model;
[0028] Figure 2 is a schematic diagram of the low - wear pump core structure and the structure of the plunger in an excavator hydraulic pump shown in the present utility model;
[0029] Figure 3 is a schematic diagram of the low - wear pump core structure and the structure of the expansion ring and the support ring in an excavator hydraulic pump shown in the present utility model;
[0030] Figure 4 is a schematic diagram of the internal lubrication of the plunger cavity by the oil in the oil storage groove in the low - wear pump core structure and the excavator hydraulic pump shown in the present utility model.
[0031] 1. Pump body; 11. Pump cover; 2. Transmission shaft; 3. Cylinder block; 301. Plunger cavity; 4. Distribution disk; 5. Swash plate; 51. Sled; 6. Plunger; 61. Ball seat; 62. Expansion ring; 63. Support ring; 64. Magnet; 601. Oil storage groove; 7. Control valve component. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0032] In order to better understand the technical content of the present utility model, specific embodiments are hereby given and described in conjunction with the accompanying drawings as follows.
[0033] Combined with Figures 1-4As shown in the figure, the utility model provides a low-wear pump core structure, which includes a cylinder block 3 and a plunger 6.
[0034] A plurality of plunger cavities 301 evenly distributed circumferentially are formed on the cylinder block 3, and a plunger 6 slides in each plunger cavity 301. As the cylinder block 3 rotates, the plunger 6 reciprocates in the plunger cavity 301, and for each rotation of the cylinder block 3, the plunger 6 reciprocates once in the plunger cavity 301.
[0035] The existing lubrication method is to apply lubricating oil in the fitting clearance between the plunger and the cylinder block to form a lubricating oil layer between the plunger and the cylinder block. However, in order to reduce weight, enhance cooling, and reduce the thermal expansion of materials, the plungers of large-sized excavator hydraulic pumps are often designed as hollow structures. Therefore, during the oil pumping process of the plunger pump, the oil pressure in the inner cavity of the plunger increases, resulting in an increase in the bulging diameter at the end of the plunger. At this time, the clearance between the plunger and the plunger cavity decreases. During the oil pumping process of the plunger pump, the oil on the inner wall of the plunger cavity will be scraped to one end by the end of the plunger, resulting in a reduction in the lubricating oil between the plunger and the inner wall of the plunger cavity, insufficient lubrication, and increased wear.
[0036] Combined with Figure 2 and Figure 4 As shown in the figure, an oil storage groove 601 is formed at one end of the plunger 6 located in the plunger cavity 301. When the plunger 6 is installed in the plunger cavity 301, the oil storage groove 601 is enclosed by the plunger cavity 301 to form a cavity for storing lubricating oil. During the process of the plunger 6 sliding in the oil pumping direction, the lubricating oil inside the oil storage groove 601 can lubricate the contact area between the plunger 6 and the inner wall of the plunger cavity 301, forming an oil film between the plunger 6 and the inner wall of the plunger cavity 301 and reducing wear.
[0037] Furthermore, an expansion ring 62 that can expand when heated is sleeved inside the oil storage groove 601 to increase the pressure inside the oil storage groove 601. During the reciprocating movement of the plunger 6 for oil suction - oil pumping, heat will be generated by friction. When the expansion ring 62 is heated, under the action of thermal expansion and contraction, the expansion ring 62 expands, the internal space of the oil storage groove 601 decreases, and the lubricating oil inside the oil storage groove 601 is squeezed against the inner wall of the plunger cavity 301, improving the lubrication effect.
[0038] In an optional embodiment, the thickness of the expansion ring 62 is 1 / 2 of the depth of the oil storage groove 601, so that the expansion ring 62 has sufficient thermal expansion distance. The distance between the outer diameter of the expansion ring 62 and the outer diameter of the oil storage groove 601 is 2.0 - 3.0 mm, and the preferred distance is 3.0 mm, which can store more lubricating oil.
[0039] In a specific embodiment, the expansion ring 62 is made of rubber material. Compared with iron, rubber has a larger thermal expansion coefficient, good elasticity, better fatigue resistance, and longer service life.
[0040] Combined withFigure 2 and Figure 3 As shown in Figure 3 , the expansion ring 62 is arranged as two symmetrical semi-circular ring structures. During installation, it can be installed radially in the oil storage tank 601 to avoid stretching the expansion ring 62 during installation. The width of the expansion ring 62 is the same as that of the oil storage tank 601, so that the expansion ring 62 will not axially shake in the oil storage tank 601.
[0041] Furthermore, a support ring 63 for maintaining its semi-circular ring shape is fixed on the inner side wall of the expansion ring 62, so that the expansion ring 62 is always in a semi-circular ring shape and fits in the oil storage tank 601. The width of the support ring 63 is the same as that of the oil storage tank 601, so that the support ring 63 will not axially shake in the oil storage tank 601.
[0042] Combined with Figure 3 As shown in Figure 3 , a plurality of uniformly distributed magnets 64 are provided on the support ring 63, which can adsorb the worn and fallen magnetic metal particles to avoid the metal particles aggravating the wear. At the same time, the support ring 63 is connected to the inside of the oil storage tank 601 by magnetic suction force, which is convenient for installation and disassembly. The magnet 64 is a neodymium iron boron magnet, which has strong magnetism and the magnetic adsorption connection is relatively stable.
[0043] In the second aspect of the present utility model, an excavator hydraulic pump is proposed, which includes a pump body 1, a pump cover 11, a drive shaft 2, a distribution plate 4, a swash plate 5 and the above-mentioned low-wear pump core structure.
[0044] Among them, a pump cover 11 is provided at one end of the pump body 1. A drive shaft 2 is arranged inside the pump body 1. One end of the drive shaft 2 extends to the outside of the pump body 1 for connecting with the engine. The cylinder block 3 is coaxially arranged on the drive shaft 2 and rotates synchronously with the drive shaft 2. The engine of the excavator drives the cylinder block 3 to rotate through the drive shaft 2.
[0045] Combined with Figure 1 As shown in Figure 1 , a skid 51 is provided between the plunger 6 and the swash plate 5. A spherical seat 61 connected to the skid 51 is provided on the plunger 6. The plunger 6 is connected to the swash plate 5 through the skid 51. As the cylinder block 3 rotates, the plunger 6 reciprocates in the plunger cavity 301, and for each rotation of the cylinder block 3, the plunger 6 reciprocates once in the plunger cavity 301.
[0046] The distribution plate 4 is arranged on the pump cover 11 and is in sliding contact with the first end of the cylinder block 3. An oil inlet cavity and an oil discharge cavity corresponding to the plunger cavity 301 are provided on the distribution plate 4. Hydraulic oil flow channels corresponding to the oil inlet cavity and the oil discharge cavity are provided on the pump cover 11. When the cylinder block 3 rotates and the plunger cavity 301 is located in the oil inlet cavity area, the plunger 6 moves away from the distribution plate 4, and the volume of the plunger cavity 301 increases, sucking oil. When the cylinder block 3 rotates and the plunger cavity 301 is located in the oil discharge cavity area, the plunger 6 moves towards the distribution plate 4, and the volume of the plunger cavity 301 decreases, pumping out oil.
[0047] A control valve component 7 for adjusting the tilt angle of the swash plate 5 is provided on the pump body 1 to change the reciprocating stroke of the plunger 6.
[0048] In a specific embodiment, the control valve component 7 includes an electric valve and a linkage mechanism. The electric valve adjusts the tilt angle of the swash plate 5 through the linkage mechanism to change the reciprocating stroke of the plunger 6.
[0049] Combined with the above embodiments, by providing an oil storage groove 601 on the plunger 6, when the plunger 6 is installed in the plunger cavity 301, the oil storage groove 601 is enclosed by the plunger cavity 301 as a cavity for storing lubricating oil. The lubricating oil inside the oil storage groove 601 can lubricate the area where the plunger 6 contacts the inner wall of the plunger cavity 301 during the process of the plunger 6 sliding in the oil pumping direction, forming an oil film between the plunger 6 and the inner wall of the plunger cavity 301 and reducing wear.
[0050] An expansion ring 62 that can expand when heated is sleeved inside the oil storage groove 601 to increase the pressure inside the oil storage groove 601. During the process of the plunger 6 reciprocating for oil suction - oil pumping, heat will be generated by friction. When the expansion ring 62 is heated, under the action of thermal expansion and contraction, the expansion ring 62 expands, the internal space of the oil storage groove 601 decreases, and the lubricating oil inside the oil storage groove 601 is extruded against the inner wall of the plunger cavity 301, improving the lubrication effect.
[0051] Although the present utility model has been disclosed above with preferred embodiments, it is not intended to limit the present utility model. Those with ordinary knowledge in the technical field to which the present utility model pertains can make various modifications and refinements without departing from the spirit and scope of the present utility model. Therefore, the protection scope of the present utility model shall be subject to what is defined by the claims.
Claims
1. Low-wear pump core structure, characterized in that, Comprising: A cylinder block (3) having a plurality of plunger chambers (301) evenly distributed circumferentially thereon; Plungers (6) corresponding to the number of the plunger chambers (301), respectively disposed in the plunger chambers (301), and the plungers (6) are configured to reciprocate within the plunger chambers (301); Wherein, one end of the plunger (6) located within the plunger chamber (301) is provided with an oil storage groove (601). When the plunger (6) is installed into the plunger chamber (301), the oil storage groove (601) is enclosed by the plunger chamber (301) to form a cavity for storing lubricating oil. An expansion ring (62) capable of thermally expanding is sleeved within the oil storage groove (601) for increasing the pressure within the oil storage groove (601).
2. The low-wear pump core structure according to claim 1, wherein The thickness of the expansion ring (62) is 1 / 2 of the depth of the oil storage groove (601).
3. The low-wear pump core structure according to claim 1, characterized in that The spacing between the outer diameter of the expansion ring (62) and the outer diameter of the oil storage groove (601) is 2.0 - 3.0 mm.
4. The low-wear pump core structure according to claim 1, wherein, The expansion ring (62) is made of rubber material.
5. The low-wear pump core structure according to claim 1, characterized in that The expansion ring (62) is provided with two symmetrical semi - circular ring structures, and the width of the expansion ring (62) is the same as the width of the oil storage groove (601).
6. The low-wear pump core structure according to claim 1, characterized in that A support ring (63) for maintaining its semi - circular ring shape is fixed to the inner side wall of the expansion ring (62), and the width of the support ring (63) is the same as the width of the oil storage groove (601).
7. The low-wear pump core structure according to claim 6, wherein, A plurality of evenly distributed magnets (64) are provided on the support ring (63) for adsorbing worn - off magnetic metal particles.
8. The hydraulic pump of an excavator, characterized in that, Comprising: A pump body (1), one end of the pump body (1) is provided with a pump cover (11), and a transmission shaft (2) is disposed inside the pump body (1); The low - wear pump core structure according to any one of claims 1 - 7, wherein the cylinder block (3) in the pump core structure is disposed on the transmission shaft (2) and rotates synchronously with the transmission shaft (2); A distribution disk (4) is disposed on the pump cover (11) and is in sliding contact with the first end of the cylinder block (3). The distribution disk (4) is provided with an oil inlet chamber and an oil discharge chamber corresponding to the plunger chambers (301); An inclined disk (5) is located at the second end of the cylinder block (3), and the plunger (6) is connected to the inclined disk (5); Wherein, when the cylinder block (3) rotates one week, the plunger (6) reciprocates once within the plunger chamber (301).
9. The hydraulic pump of an excavator according to claim 8, characterized in that, A skid (51) is provided between the plunger (6) and the inclined disk (5). A spherical seat (61) connected to the skid (51) is provided on the plunger (6), and the plunger (6) is connected to the inclined disk (5) through the skid (51).
10. The hydraulic pump of an excavator according to claim 8, characterized in that, A control valve component (7) for adjusting the inclination angle of the inclined disk (5) is provided on the pump body (1) to change the reciprocating stroke of the plunger (6).