Plunger assembly lubricated by working medium and radial plunger pump

Abstract

The invention provides a plunger assembly lubricated by a working medium and a radial plunger pump, and belongs to the field of plunger pumps. The plunger assembly lubricated by the working medium comprises a pump body and a plunger, a plunger hole allowing the plunger to reciprocate and a pumping channel with the middle communicated with the plunger hole are formed in the pump body, the pump body is provided with a columnar structure, a guide sleeve is arranged on the columnar structure in a sleeving mode, and a liquid inlet channel allowing the working medium to flow into the guide sleeve from the outside in a one-way mode is formed in the pump body. And the end wall of the guide sleeve is provided with a lubricating through hole through which a working medium in an inner cavity of the guide sleeve flows to the outer surface of the end wall and provides lubrication during working. The radial plunger pump lubricated by the working medium comprises the plunger assembly lubricated by the working medium. According to the radial plunger pump, a new pump structure is designed in the plunger assembly, the pump structure can pump a working medium to a part needing to be lubricated, and the working medium is used for providing lubrication for the working process of the radial plunger pump.

Description

Technical Field

[0001] This invention belongs to the field of plunger pumps, and in particular relates to a plunger assembly for working medium lubrication and a radial plunger pump. Background Technology

[0002] Radial piston pumps can pressurize water to ultra-high pressure (e.g., above 100 MPa), directly utilizing its pressure energy for processing (such as waterjet processing, water-guided laser processing, etc.), and have become a revolutionary technology in the field of special processing. In addition to pressurizing water, radial piston pumps can also be used to pressurize working media such as water-ethylene glycol, emulsions, aviation kerosene, gasoline, and diesel.

[0003] Traditional radial piston pumps require a dedicated lubricating oil to lubricate their operation. A special storage space for the lubricating oil is needed inside the pump, which not only results in a larger product size and weight, but also requires regular lubrication. Furthermore, there is a problem of mutual penetration between the lubricating oil and the working medium, affecting the cleanliness of the working medium. Summary of the Invention

[0004] The purpose of this invention is to provide a plunger assembly for working medium lubrication, so as to solve the technical problem that the plunger pump in the prior art requires special lubricating oil for lubrication, which easily contaminates the working medium.

[0005] Another object of the present invention is to provide a radial piston pump lubricated by a working medium to solve the above-mentioned technical problems.

[0006] To achieve the above objectives, the technical solution for the working medium lubricated plunger assembly provided by the present invention is as follows: A plunger assembly for working medium lubrication includes a pump body and a plunger. The pump body has a plug hole for reciprocating motion of the plunger and a pumping channel communicating with the plug hole in the middle. The pump body has a columnar structure and a guide sleeve is fitted on the columnar structure. The plunger is located inside the guide sleeve and can move into the pump body under the push of the end wall of the guide sleeve. The pump body has an inlet channel for the working medium to flow unidirectionally into the guide sleeve from the outside. The end wall of the guide sleeve has a lubrication through hole for the working medium in its inner cavity to flow to the outer surface of the end wall and provide lubrication during operation. An elastic element is provided between the guide sleeve and the pump body for driving the guide sleeve to move away from the pump body. A reset traction structure is provided between the guide sleeve and the plunger, or an elastic push structure is provided between the pump body and the plunger so that the plunger can be reset with the guide sleeve.

[0007] As a further improvement, a lubrication groove for storing working medium is provided on the outer surface of the guide sleeve end wall, and the lubrication groove is connected to the lubrication through hole.

[0008] As a further improvement, the lubrication groove includes an annular groove distributed around the lubrication through hole and radial grooves distributed radially around the lubrication through hole, the radial grooves connecting the lubrication through hole and the annular groove.

[0009] As a further improvement, the pump body is provided with a rotating mating hole for rotatably mounting to the housing of the radial plunger pump via a mounting shaft. The outer surface of the end wall of the guide sleeve is an arc-shaped surface adapted to the shape of the outer circumferential surface of the eccentric structure. The pump body is also provided with a lubrication channel for the working medium inside the guide sleeve to flow into the rotating mating hole and provide lubrication during use.

[0010] As a further improvement, the lubrication channel includes two outlet holes that connect the end face of the columnar structure and the inner wall of the rotating mating hole, respectively. The two outlet holes are arranged along the axial direction of the rotating mating hole, and the plug hole and the inlet channel are located on both sides of the surface where the two outlet holes are located.

[0011] As a further improvement, a reset traction structure is provided between the guide sleeve and the plunger. The plunger includes a main body and a protruding edge provided at one end of the main body extending out of the pump body. The guide sleeve is provided with a baffle that leaves space between it and the end wall of the guide sleeve. The baffle is provided with a through hole for the main body of the plunger to pass through. The protruding edge is located between the baffle and the end wall of the guide sleeve. The contours of the through hole, the main body of the plunger, and the protruding edge meet the requirement that the protruding edge can move between the end wall of the guide sleeve and the baffle during use without falling out. The protruding edge and the baffle constitute the reset traction structure.

[0012] As a further improvement, the orifice includes a large contour area and a small contour area. The size of the large contour area is such that the protruding edge on the plunger can pass through, while the size of the small contour area is such that the main body of the plunger can pass through but the protruding edge cannot. During operation, the plunger is always located in the small contour area.

[0013] As a further improvement, the guide sleeve includes a main sleeve body and a stop and a wear-resistant sleeve installed in the main sleeve body. The stop includes a plate body and a support flange provided at the edge of the plate body. The support flange supports the inner surface of the end wall of the main sleeve body so that a space is left between the inner surface of the end wall of the main sleeve body and the plate body. The plate body constitutes the baffle. The wear-resistant sleeve is interference-fitted or glued to the main sleeve body and presses against the stop.

[0014] As a further improvement, the pump body includes a main body and a plug. The plug hole is a through hole that extends through the main body along its extension direction. The plug is installed at one end of the plug hole away from the guide sleeve. An elastic pushing structure is provided between the pump body and the plunger. The elastic pushing structure is a helical spring that is set in the plug hole and whose two ends abut against the plug and the plunger respectively. A limiting post is provided at one end of the plug that extends into the plug hole and is inserted into the helical spring to provide radial limit for the helical spring.

[0015] The beneficial effects are as follows: The working medium lubricated plunger assembly provided by this invention is an improvement on the prior art. In this working medium lubricated plunger assembly, the guide sleeve can cooperate with the columnar structure of the pump body to form a new pump structure. This pump structure pumps the working medium to the part that needs lubrication, and uses the working medium to provide lubrication for the working process of the radial plunger pump. There is no need to provide a special storage space for lubricating oil inside the pump, and there is no problem of mutual seepage between lubricating oil and working medium, which would contaminate the working medium.

[0016] To achieve the above objectives, the technical solution of the radial piston pump with working medium lubrication provided by the present invention is as follows: A radial plunger pump lubricated by a working medium includes a housing, a rotating shaft, and plunger assemblies arranged around the rotating shaft. An eccentric structure for pushing each plunger assembly is provided on the rotating shaft. Each plunger assembly includes a pump body and plungers. The pump body has a plug hole for reciprocating motion of the plungers and a pumping channel communicating with the plug hole in the middle. The pump body has a columnar structure and a guide sleeve is fitted onto the columnar structure. The plungers are located inside the guide sleeve and can move into the pump body under the pushing force of the guide sleeve end wall. The pump body has an inlet channel for the working medium to flow unidirectionally into the guide sleeve from the outside. The end wall of the guide sleeve has a lubrication through hole for the working medium in its inner cavity to flow to the outer surface of the end wall and provide lubrication during operation. An elastic element for driving the guide sleeve to move away from the pump body is provided between the guide sleeve and the pump body. A reset traction structure is provided between the guide sleeve and the plungers, or an elastic pushing structure is provided between the pump body and the plungers so that the plungers can reset with the guide sleeve.

[0017] As a further improvement, a lubrication groove for storing working medium is provided on the outer surface of the guide sleeve end wall, and the lubrication groove is connected to the lubrication through hole.

[0018] As a further improvement, the lubrication groove includes an annular groove distributed around the lubrication through hole and radial grooves distributed radially around the lubrication through hole, the radial grooves connecting the lubrication through hole and the annular groove.

[0019] As a further improvement, the pump body is provided with a rotating mating hole for rotatably mounting to the housing of the radial plunger pump via a mounting shaft. The outer surface of the end wall of the guide sleeve is an arc-shaped surface adapted to the shape of the outer circumferential surface of the eccentric structure. The pump body is also provided with a lubrication channel for the working medium inside the guide sleeve to flow into the rotating mating hole and provide lubrication during use.

[0020] As a further improvement, the lubrication channel includes two outlet holes that connect the end face of the columnar structure and the inner wall of the rotating mating hole, respectively. The two outlet holes are arranged along the axial direction of the rotating mating hole, and the plug hole and the inlet channel are located on both sides of the surface where the two outlet holes are located.

[0021] As a further improvement, a reset traction structure is provided between the guide sleeve and the plunger. The plunger includes a main body and a protruding edge provided at one end of the main body extending out of the pump body. The guide sleeve is provided with a baffle that leaves space between it and the end wall of the guide sleeve. The baffle is provided with a through hole for the main body of the plunger to pass through. The protruding edge is located between the baffle and the end wall of the guide sleeve. The contours of the through hole, the main body of the plunger, and the protruding edge meet the requirement that the protruding edge can move between the end wall of the guide sleeve and the baffle during use without falling out. The protruding edge and the baffle constitute the reset traction structure.

[0022] As a further improvement, the orifice includes a large contour area and a small contour area. The size of the large contour area is such that the protruding edge on the plunger can pass through, while the size of the small contour area is such that the main body of the plunger can pass through but the protruding edge cannot. During operation, the plunger is always located in the small contour area.

[0023] As a further improvement, the guide sleeve includes a main sleeve body and a stop and a wear-resistant sleeve installed in the main sleeve body. The stop includes a plate body and a support flange provided at the edge of the plate body. The support flange supports the inner surface of the end wall of the main sleeve body so that a space is left between the inner surface of the end wall of the main sleeve body and the plate body. The plate body constitutes the baffle. The wear-resistant sleeve is interference-fitted or glued to the main sleeve body and presses against the stop.

[0024] As a further improvement, the pump body includes a main body and a plug. The plug hole is a through hole that extends through the main body along its extension direction. The plug is installed at one end of the plug hole away from the guide sleeve. An elastic pushing structure is provided between the pump body and the plunger. The elastic pushing structure is a helical spring that is set in the plug hole and whose two ends abut against the plug and the plunger respectively. A limiting post is provided at one end of the plug that extends into the plug hole and is inserted into the helical spring to provide radial limit for the helical spring.

[0025] The beneficial effects are as follows: The radial piston pump with working medium lubrication provided by this invention is an improvement on the prior art. This radial piston pump with working medium lubrication employs a new piston assembly. In this new piston assembly, the guide sleeve can cooperate with the columnar structure of the pump body to form a new pump structure. This pump structure pumps the working medium to the parts requiring lubrication, using the working medium to provide lubrication for the working process of the radial piston pump. There is no need to provide a dedicated storage space for lubricating oil inside the pump, and the problem of mutual seepage between lubricating oil and the working medium, thus avoiding contamination of the working medium, is also avoided. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the radial plunger pump with working medium lubrication in this invention; Figure 2 This is a schematic diagram of the end cover structure in Embodiment 1 of the radial plunger pump with working medium lubrication in this invention; Figure 3This is a schematic diagram of the shaft structure in Embodiment 1 of the radial piston pump with working medium lubrication in this invention; Figure 4 This is a cross-sectional view of the plunger assembly in Embodiment 1 of the radial plunger pump with working medium lubrication in this invention. Figure 5 This is a cross-sectional view of the plunger assembly in Embodiment 1 of the radial plunger pump with working medium lubrication according to the present invention from another perspective. Figure 6 This is a schematic diagram of the pump body in Embodiment 1 of the radial plunger pump for working medium lubrication in this invention; Figure 7 This is a cross-sectional view of the pump body in Embodiment 1 of the radial piston pump for working medium lubrication in this invention; Figure 8 for Figure 7 Sectional view at point AA; Figure 9 This is a schematic diagram of the guide sleeve in Embodiment 1 of the radial plunger pump with working medium lubrication in this invention; Figure 10 This is a cross-sectional view of the guide sleeve in Embodiment 1 of the radial piston pump with working medium lubrication in this invention. Figure 11 This is a cross-sectional view of the guide sleeve from another perspective in Embodiment 1 of the radial piston pump with working medium lubrication in this invention. Figure 12 This is a schematic diagram of the plunger structure in Embodiment 1 of the radial plunger pump with working medium lubrication in this invention; Figure 13 This is a schematic diagram of the stop component in Embodiment 1 of the radial piston pump with working medium lubrication in this invention; Figure 14 This is a schematic diagram of the plunger assembly in Embodiment 3 of the radial plunger pump with working medium lubrication in this invention.

[0027] Explanation of reference numerals in the attached figures: 1. End cap; 11. Circumferential channel; 12. Connecting channel; 13. Pump outlet channel; 14. Mounting shaft; 2. Motor; 3. Rotating shaft; 31. Eccentric shaft section; 32. Regular pentagonal structure; 4. Plunger assembly; 41. Pump body; 411. Pumping channel; 412. Pumping suction valve; 413. Discharge valve; 414. Plug hole; 415. Columnar structure; 416. Rotary mating hole; 417. Liquid inlet channel; 418. Lubrication suction valve; 419. Liquid outlet; 42. Plunger; 421. Spherical surface; 422. Raised edge; 43. Guide sleeve; 431. Mating surface; 432. Main sleeve body; 433. Wear-resistant sleeve; 434. Stop; 435. Through hole; 4351. Large contour area; 4352. Small contour area; 436. Lubrication pump chamber; 437. Lubrication through hole; 438. Lubrication groove; 4381. Circulating groove; 4382. Radial groove; 44. External helical spring. Detailed Implementation

[0028] The present invention will be further described in detail below with reference to the embodiments.

[0029] Specific Embodiment 1 of the radial piston pump with working medium lubrication provided by the present invention: This radial piston pump uses the working medium to lubricate the friction interface between the components, eliminating the need for additional lubricating oil and thus preventing the working medium from being contaminated by lubricating oil.

[0030] See appendix Figure 1 The radial piston pump includes a housing, a rotating shaft 3, and a piston assembly 4.

[0031] The outer casing includes a housing and an end cover 1. The end cover 1 is sealed to one axial end of the housing. The housing mainly serves to enclose the inner cavity of the outer casing together with the end cover 1. The end cover 1 is mainly used to install other structures of the radial piston pump and to bear loads; therefore, the thickness of the end cover 1 is greater than the thickness of the housing. A pump inlet is provided at the center of the axial end wall of the housing, and a pump outlet is provided on the outer periphery of the end cover 1. A collection channel communicating with the pump outlet and allowing the working medium to be discharged from the pump outlet is provided inside the end cover 1.

[0032] See appendix Figure 2 The end cap 1 has a through hole in its center for the rotating shaft 3 to pass through. The rotating shaft 3 rotatably engages with the through hole on the end cap 1, and a shaft seal structure is provided between the rotating shaft 3 and the end cap 1. One end of the rotating shaft 3 that extends into the inner cavity of the outer casing is suspended. See Appendix Figure 3 In this embodiment, the rotating shaft 3 is the output shaft of the motor 2 configured for the radial piston pump. In other embodiments, the rotating shaft 3 can also be set independently and then connected to the motor 2 via a coupling.

[0033] An eccentric structure is provided on the rotating shaft 3. During the rotation of the rotating shaft 3, the eccentric structure can push each plunger assembly 4 in sequence. In this embodiment, the eccentric structure is an eccentric shaft segment 31 integrally formed on the rotating shaft 3. In other embodiments, the eccentric structure can also be an independently machined component installed on the rotating shaft 3.

[0034] Five plunger assemblies 4 are provided, and each plunger assembly 4 is evenly distributed around the rotating shaft 3. In other embodiments, three, four, or six plunger assemblies 4 may also be provided, and the specific number can be determined as needed. The plunger assembly 4 includes a pump body 41, a plunger 42, and a guide sleeve 43. The pump body 41 is mounted on the inner side of the end cover 1, the plunger 42 is installed inside the pump body 41, and the guide sleeve 43 is installed outside the pump body 41.

[0035] Specifically, see Appendix Figure 4 Appendix Figure 5 and in conjunction with the appendix Figure 6 Appendix Figure 7 and appendix Figure 8 The pump body 41 is provided with a pumping channel 411 for pumping the working medium. The pumping channel 411 runs through the pump body 41 and its extension direction is perpendicular to the axis of the radial piston pump. One end of the pumping channel 411 is its inlet and the other end is its outlet. A pumping suction valve 412 and a discharge valve 413 are respectively provided at the inlet and outlet of the pumping channel 411. Both the pumping suction valve 412 and the discharge valve 413 are valves that allow the working medium to pass through in one direction.

[0036] The pump body 41 also has a plug hole 414, which extends radially along the radial direction of the radial piston pump. The end of the plug hole 414 near the shaft 3 is open, and the end away from the shaft 3 is closed. The piston 42 enters the plug hole 414 from the end near the shaft 3 and can reciprocate within it. The piston 42 is made of ceramic to reduce friction and wear between the piston 42 and the plug hole 414. The plug hole 414 is connected to the middle of the pumping channel 411. As the piston 42 reciprocates within the plug hole 414, the space within the plug hole 414 and the pumping channel 411 changes. When this space increases, a negative pressure is created, and the pumping channel 411 draws in the working medium from the inlet. When this space decreases, a positive pressure is created, and the pumping channel 411 discharges the working medium from the outlet. The flow path of the working medium during this process is shown in the appendix. Figure 5 As shown by the dashed arrow, the outer circumferential surface of the plunger 42 and the plug hole 414 are precisely clearance-fitted, with a fit length of 6-10 times the diameter of the plunger 42, sealing the fluid inside the plug hole 414 and creating a pressure of 100-300 MPa within the plug hole 414 and the pumping channel 411.

[0037] The outlet of pumping channel 411 is connected to the collecting channel on end cap 1 via a pressure-bearing hose. The working medium discharged from each plunger assembly 4 enters the collecting channel and, after converging, is discharged from the pump outlet. See Appendix Figure 2 The flow collection channel includes an annular channel 11. At each location where a plunger assembly 4 is installed, a radially extending connecting channel 12 is provided on the end cover 1, communicating with the annular channel 11. The connecting channel 12 serves as the inlet of the flow collection channel and communicates with the outlet of the corresponding pumping channel 411. The flow collection channel also includes a radially extending pumping channel 13. One end of the pumping channel 13 communicates with the annular channel, and the other end penetrates the outer circumference of the end cover 1. The end of the pumping channel 13 furthest from the annular channel constitutes the outlet of the flow collection channel and also the pump outlet of the entire radial plunger pump.

[0038] The portion of the pump body 41 near the rotating shaft 3 is a cylindrical structure 415, while the portion of the pump body 41 away from the rotating shaft 3 is its head. The structure connecting the pump body 41 to the end cover 1 and the structure for the inlet and outlet of the working medium are both located in the head. The guide sleeve 43 is fitted over the cylindrical structure 415 and guides and cooperates with the cylindrical structure 415, enabling the guide sleeve 43 to reciprocate. Furthermore, the plug hole 414 passes through the cylindrical structure 415, and the axis of the plug hole 414 is parallel to the axis of the cylindrical structure 415, so that the reciprocating direction of the guide sleeve 43 is in the same direction as the reciprocating direction of the plunger 42.

[0039] Each plunger assembly 4 is provided with a mounting shaft 14 on the end cap 1. The head of the pump body 41 is provided with a rotating engagement hole 416 that rotatably engages with the mounting shaft 14, allowing the entire plunger assembly 4 to swing around the rotating engagement hole 416 as the center. See Appendix Figure 9 Appendix Figure 10 and appendix Figure 11 The end of the guide sleeve 43 facing the rotating shaft 3 is closed by an end wall. The outer surface of the end wall of the guide sleeve 43 is a mating surface 431 that fits against the outer peripheral surface of the eccentric shaft section 31 and can slide relative to it. The mating surface 431 is an arc-shaped surface that matches the shape of the outer peripheral surface of the eccentric shaft section 31. During operation, the plunger assembly 4 can adjust its own posture in real time by swinging according to the position of the eccentric structure. This is more conducive to reducing the lateral force on the plunger 42 and reducing the wear of the plunger 42.

[0040] One end of the plunger 42 extending out of the pump body 41 is located inside the guide sleeve 43 and abuts against the inner surface of the end wall of the guide sleeve 43. When the eccentric structure pushes the guide sleeve 43, the guide sleeve 43 can transmit the force to the plunger 42. When the contact point of the eccentric structure guide sleeve 43 deviates from its own axis, the guide sleeve 43 bears a lateral force. Since the guide sleeve 43 and the pump body 41 can guide and cooperate, the movement posture of the guide sleeve 43 will not change, and thus the lateral force will not be transmitted to the plunger 42, reducing the eccentric wear of the plunger 42.

[0041] However, in reality, due to factors such as machining precision, there may be a certain gap between the guide sleeve 43 and the pump body 41, which may cause a certain amount of wobble in the guide sleeve 43 during actual operation. See appendix. Figure 12 In this embodiment, the end face of the plunger 42 that is used to abut against the guide sleeve 43 is set as a spherical surface 421. On the one hand, this can further ensure that the force of the guide sleeve 43 on the plunger 42 can be along the axial direction of the plunger 42 itself, and further reduce the wear of the plunger 42. On the other hand, it can also reduce the friction between the guide sleeve 43 and the plunger 42, and reduce the working resistance.

[0042] Under the jacking force of the eccentric structure, both the guide sleeve 43 and the plunger 42 will move towards the pump body 41. After the jacking is completed, the guide sleeve 43 and the plunger 42 need to move away from the pump body 41. This process is the reset process of the guide sleeve 43 and the plunger 42. The reset of the guide sleeve 43 is achieved by an elastic element. An elastic element is provided between the guide sleeve 43 and the pump body 41 to move the guide sleeve 43 away from the pump body 41 to achieve reset. This elastic element is specifically an external helical spring 44. The two ends of the external helical spring 44 are respectively pressed against the abutment shoulders on the pump body 41 and the guide sleeve 43. During use, the external helical spring 44 is always in a compressed state.

[0043] The reset driving force for the plunger 42 is provided by a reset traction structure provided between the guide sleeve 43 and the plunger 42. The reset traction structure can pull the plunger 42 to reset together when the guide sleeve 43 resets. The reset traction structure includes a stop part provided on the guide sleeve 43 and a stop engagement part provided on the plunger 42. The stop part is located on the side of the stop engagement part away from the end wall of the guide sleeve 43. When the guide sleeve 43 resets, the stop part pushes against the stop engagement part, transmitting the reset power to the plunger 42.

[0044] In one embodiment of this invention, the plunger 42 has a radially protruding flange 422 at one end extending from the pump body 41, which constitutes the aforementioned stop-fitting part. The guide sleeve 43 includes a main sleeve body 432 and a stop member 434 and a wear-resistant sleeve 433 installed inside the main sleeve body 432. The stop member 434 includes a plate and a support flange provided at the edge of the plate. The support flange is supported on the inner surface of the end wall of the main sleeve body 432 so that there is a space between the inner surface of the end wall of the main sleeve body 432 and the plate. The plate constitutes a baffle for stop-fitting with the flange 422. The wear-resistant sleeve 433 is interference-fitted or glued inside the main sleeve body 432 and presses against the stop member 434.

[0045] The baffle is provided with a through hole 435 for the main body of the plunger 42 to pass through. The contours of the through hole 435, the main body of the plunger 42, and the protrusion 422 are such that the protrusion 422 can move between the end wall of the guide sleeve 43 and the baffle when in use, but cannot be dislodged. The area on the baffle used to stop and cooperate with the stop-fitting part constitutes the aforementioned stop part.

[0046] The wear-resistant sleeve 433 enhances the wear resistance between the guide sleeve 43 and the pump body 41. Simultaneously, the wear-resistant sleeve 433 also secures the stop member 434, ensuring a relatively simple overall structure and easy assembly of the plunger assembly 4. The wear-resistant sleeve 433 can be optionally provided. In other embodiments, if the wear-resistant sleeve 433 is not provided, the stop member 434 can be directly interference-fitted into the main sleeve 432, or welded and fixed into the main sleeve 432. In embodiments without the wear-resistant sleeve 433, the stop member 434 can also be a circular plate and welded and fixed into the main sleeve 432. During welding, a certain space is left between the stop member 434 and the end wall of the main sleeve 432; in this case, the stop member 434 as a whole constitutes a baffle.

[0047] See appendix Figure 13 The hole 435 includes a large contour area 4351 and a small contour area 4352, which are connected. The shape and size of the large contour area 4351 are sufficient to allow the protruding edge 422 on the plunger 42 to pass through. This facilitates the assembly of the guide sleeve 43 as a whole, and then its assembly with the plunger 42. When the plunger 42 is assembled, its protruding edge 422 passes through the large contour area 4351 and enters the space between the baffle and the end wall of the guide sleeve 43. Then, the plunger 42 moves laterally to the small contour area 4352. When the plunger assembly 4 is working normally, the plunger 42 is always located in the small contour area 4352, and the protruding edge 422 of the plunger 42 cannot pass through the small contour area 4352. The baffle at the small contour area 4352 constitutes a stop that can stop and cooperate with the protruding edge 422 of the plunger 42.

[0048] In other embodiments, the through hole 435 may only include a small contour area 4352. In this case, for ease of assembly, the plunger 42 needs to pass through the through hole 435 on the baffle beforehand, and then when fixing the baffle, the protruding edge 422 of the plunger 42 remains between the baffle and the end wall of the plunger 42. When the through hole 435 only includes a small contour area 4352, the contour of the through hole 435 can have various forms. When the contours of the through hole 435, the main body of the plunger 42, and the protruding edge 422 are all circular, the radial dimension of the contour of the through hole 435 is larger than the radial dimension of the contour of the main body of the plunger 42 but smaller than the radial dimension of the contour of the protruding edge 422. When the contour of the protruding edge 422 is set to be rectangular and the contours of the through hole 435 and the main body of the plunger 42 are both circular, as long as the length of the contour of the protruding edge 422 is greater than the radial dimension of the contour of the through hole 435, it can be ensured that the protruding edge 422 will not come out.

[0049] It should be noted that when the end face of the plunger 42 is pressed against the inner surface of the end wall of the guide sleeve 43, a certain gap needs to be left between the protruding edge 422 and the baffle. The value of this gap is in the range of 0.02-0.05mm. This ensures that the plunger 42 can make a small movement along its own radial direction between the end wall of the guide sleeve 43 and the baffle, and also prevents vibration and noise from occurring during the movement of the plunger 42.

[0050] The guide sleeve 43 and the columnar structure 415 of the pump body 41 are fitted with a small clearance, allowing the working medium inside the guide sleeve 43 to generate a pressure of 0.1-1 MPa. During the reciprocating motion of the guide sleeve 43 relative to the pump body 41, the columnar structure 415 on the pump body 41 acts as a piston. At this time, the columnar structure 415 of the pump body 41 and the guide sleeve 43 can form a new pump structure, such as... Figure 4 and Figure 5 The path indicated by the solid arrow shows that the pump structure pumps the working medium to the parts that require lubrication. The working medium provides lubrication for the operation of the radial plunger pump. There is no need to provide a special storage space for lubricating oil inside the pump, and there is no problem of mutual seepage between lubricating oil and working medium, which would contaminate the working medium.

[0051] In the new pump structure, the space enclosed by the guide sleeve 43 and the columnar structure 415 of the pump body 41 constitutes the lubrication pump chamber 436. The pump body 41 is provided with an inlet channel 417 for the working medium to flow unidirectionally into the lubrication pump chamber 436 from the outside. The inlet channel 417 is a passage that passes through the columnar structure 415 along its length and connects the end face of the columnar structure 415 away from the head to the outer surface of the head. A lubrication suction valve 418 is also provided in this passage; the lubrication suction valve 418 is a one-way valve that allows the working medium to pass through unidirectionally. The inlet of the inlet channel 417 is located on the side of the pump body 41 away from the end cover 1. When the space of the lubrication pump chamber 436 increases, a negative pressure is generated in the guide sleeve 43, drawing the working medium from the inner cavity of the outer casing into the lubrication pump chamber 436 through the inlet channel 417.

[0052] A lubrication through hole 437 is provided at the center of the end wall of the guide sleeve 43. When the space of the lubrication pump chamber 436 becomes smaller, a positive pressure is generated in the guide sleeve 43, which forces the working medium in the lubrication pump chamber 436 to the outer surface of the end wall of the guide sleeve 43 through the lubrication through hole 437. This causes the working medium to form a liquid lubricating film with a certain pressure between the end wall of the guide sleeve 43 and the eccentric shaft section 31, thereby reducing the friction and wear between the guide sleeve 43 and the eccentric shaft section 31.

[0053] The guide sleeve 43 has a lubrication groove 438 on its mating surface 431 for storing the working medium. The lubrication groove 438 is connected to the lubrication through hole 437. In this way, even when no working medium is forced out from the lubrication through hole 437, the working medium stored in the lubrication groove 438 can still provide a certain lubrication effect. During operation, the pressure between the guide sleeve 43 and the eccentric shaft section 31 is greater when the space of the lubrication pump cavity 436 decreases and less when the space of the lubrication pump cavity 436 increases. Therefore, although no working medium is forced out when the space of the lubrication pump cavity 436 increases, the pressure and friction between the guide sleeve 43 and the eccentric shaft section 31 are low during this period, which can maintain a low degree of friction.

[0054] The lubrication groove 438 includes an annular groove 4381 distributed around the lubrication through hole 437 and radial grooves 4382 radially distributed around the lubrication through hole 437. The radial grooves 4382 connect the lubrication through hole 437 and the annular groove 4381. In a specific embodiment of this invention, the overall shape of the annular groove 4381 is the same as the shape of the mating surface 431, both being rectangular. This allows it to cover a larger area of ​​the mating surface 431, facilitating better lubrication. The radial grooves 4382 are cross-shaped, which allows the working medium to be distributed into the annular groove 4381 as quickly as possible.

[0055] In addition, the pump body 41 is provided with a lubrication channel that connects the end face of the columnar structure 415 away from the head to the rotating mating hole 416 on the pump body 41. When the space of the lubrication pump chamber 436 becomes smaller, the working medium in the guide sleeve 43 will also enter the rotating mating hole 416 through the lubrication channel under pressure, providing lubrication between the pump body 41 and the mounting shaft 14 and reducing friction and wear between them. The lubrication channel includes two outlet holes 419 that connect the end face of the columnar structure 415 and the inner wall of the rotating mating hole 416 respectively. The two outlet holes 419 are arranged along the axial direction of the rotating mating hole 416. The plug hole 414 and the inlet channel 417 are located on both sides of the surface where the two outlet holes 419 are located.

[0056] To further reduce friction and wear, wear-resistant layers can be provided on the inner surface of the rotating mating hole 416 of the pump body 41 and the mating surface 431 of the guide sleeve 43. When the working medium is water, the wear-resistant layer can be made of carbon fiber reinforced polyetheretherketone or ceramic materials, which are more suitable for water-lubricated environments.

[0057] Specific embodiment 2 of the radial piston pump with working medium lubrication provided by the present invention: This embodiment is based on embodiment 1. The difference between this embodiment and embodiment 1 is that the lubrication channel in this embodiment only includes one liquid outlet hole. The liquid outlet hole and the liquid inlet channel are located on both sides of the plug hole. The plug hole is located at the center of the columnar structure of the pump body and is coaxial with the columnar structure.

[0058] Specific embodiment 3 of the radial piston pump with working medium lubrication provided by the present invention: This implementation method is based on implementation method 1, and the difference between it and implementation method 1 is as follows (see Appendix). Figure 14 In this embodiment, the eccentric structure includes an eccentric shaft section 31 set on the rotating shaft 3 and a regular pentagonal structure 32 rotatably mounted on the eccentric shaft section 31. The head of the pump body 41 is provided with two mounting holes for screws to pass through. The pump body 41 is fixedly connected to the end cover 1 by two screws. The mating surface 431 on the guide sleeve 43 is a plane that slides with one side of the regular pentagon.

[0059] In this embodiment, since the pump body 41 is fixed and there is no rotating mating hole 416, there is no need to set up a lubrication channel. The working medium pressed out in the lubrication pump chamber 436 is only used to provide lubrication between the mating surface 431 of the guide sleeve 43 and the regular pentagonal structure 32.

[0060] Specific embodiment 4 of the radial piston pump with working medium lubrication provided by the present invention: This embodiment is based on embodiment 1. The difference between this embodiment and embodiment 1 is that the lubrication groove in this embodiment only includes a radial groove and does not include a surrounding groove.

[0061] Specific embodiment 5 of the radial piston pump with working medium lubrication provided by the present invention: This embodiment is based on embodiment 1. The difference between this embodiment and embodiment 1 is that the mating surface of the guide sleeve in this embodiment is a complete surface without grooves or protrusions. After the working medium is pressed into the mating surface of the guide sleeve and the eccentric structure, it can naturally flow to the surroundings to form a lubricating film.

[0062] Specific embodiment 6 of the radial piston pump with working medium lubrication provided by the present invention: This embodiment is based on Embodiment 1, but differs in that it provides an alternative structure for the plunger assembly. In this embodiment, the plunger's reset is also achieved using an elastic element, thus eliminating the need for a stopper. Specifically, an internal helical spring is provided inside the plug hole, with both ends of the internal helical spring abutting against the plunger and the end wall of the plug hole, respectively. During use, the internal helical spring is always in a compressed state.

[0063] Specific embodiment 7 of the radial piston pump with working medium lubrication provided by the present invention: This embodiment is based on embodiment 1. The difference between this embodiment and embodiment 1 is that the stop component does not rely on the wear-resistant sleeve for fixation. The stop component is directly interference-fitted into the main sleeve body, or the stop component is welded and fixed into the main sleeve body.

[0064] Specific embodiment 8 of the radial piston pump with working medium lubrication provided by the present invention: This embodiment is based on embodiment 1. The difference between this embodiment and embodiment 1 is that the stop is a circular plate and is welded and fixed in the main sleeve. During welding, a certain space is left between the stop and the end wall of the main sleeve. At this time, the stop constitutes a baffle.

[0065] Specific embodiments of the plunger assembly for working medium lubrication provided by the present invention: The plunger assembly lubricated by the working medium is the same as the plunger assembly in the specific embodiment of the radial plunger pump lubricated by the working medium described above, and will not be described again.

[0066] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the technical solutions described in the foregoing embodiments without creative effort, or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A plunger assembly for lubrication of a working medium, comprising a pump body and a plunger, wherein the pump body is provided with a plug hole for reciprocating motion of the plunger and a pumping channel communicating with the plug hole in the middle, characterized in that, The pump body is provided with a columnar structure and a guide sleeve sleeved on the columnar structure. The plunger is located inside the guide sleeve and can move into the pump body under the thrust of the end wall of the guide sleeve. The pump body is provided with a liquid inlet channel for the one-way flow of working medium from the outside into the guide sleeve. The end wall of the guide sleeve is provided with a lubricating hole for the working medium in the inner cavity of the guide sleeve to flow to the outer surface of the end wall and provide lubrication during work. The guide sleeve and the pump body are provided with an elastic member for driving the guide sleeve to move away from the pump body. The guide sleeve and the plunger are provided with a reset traction structure, or the pump body and the plunger are provided with an elastic thrust structure to enable the plunger to reset with the guide sleeve.

2. The working medium lubricated plunger assembly of claim 1 wherein, The outer surface of the end wall of the guide sleeve is provided with a lubricating groove for storing working medium. The lubricating groove is in communication with the lubricating hole.

3. The working medium lubricated plunger assembly of claim 2 wherein, The lubricating groove includes a surrounding groove distributed around the lubricating hole and a radial groove radially distributed around the lubricating hole. The radial groove communicates the lubricating hole with the surrounding groove.

4. The working medium lubricated plunger assembly according to any one of claims 1-3, characterized in that, The pump body is provided with a rotating fitting hole for rotatable installation with the shell of the radial plunger pump through the installation shaft. The outer surface of the end wall of the guide sleeve is an arc surface for shape adaptation with the outer peripheral surface of the eccentric structure. The pump body is further provided with a lubricating channel for the working medium in the guide sleeve to flow into the rotating fitting hole and provide lubrication during use.

5. The working medium lubricated plunger assembly of claim 4 wherein, The lubricating channel includes two liquid outlet holes respectively communicating the end face of the columnar structure and the inner wall surface of the rotating fitting hole. The two liquid outlet holes are arranged along the axial direction of the rotating fitting hole. The plug hole and the liquid inlet channel are respectively located on both sides of the plane where the two liquid outlet holes are located.

6. The working medium lubricated plunger assembly of any of claims 1-3, wherein, The guide sleeve and the plunger are provided with a reset traction structure. The plunger includes a main body portion and a protruding edge provided at the end of the main body portion extending out of the pump body. The guide sleeve is provided with a baffle having a space between the end wall of the guide sleeve. The baffle is provided with a through hole for the main body portion of the plunger to pass through. The protruding edge is located between the baffle and the end wall of the guide sleeve. The contours of the through hole, the main body portion of the plunger, and the protruding edge satisfy that the protruding edge can move between the end wall of the guide sleeve and the baffle during use and cannot be pulled out. The protruding edge and the baffle constitute the reset traction structure.

7. The working medium lubricated plunger assembly of claim 6 wherein, The through hole includes a large contour area and a small contour area. The size of the large contour area satisfies that the protruding edge on the plunger can pass through. The size of the small contour area satisfies that the main body portion of the plunger can pass through but the protruding edge cannot pass through. During work, the plunger is always located at the small contour area.

8. The working medium lubricated plunger assembly of claim 6 wherein, The guide sleeve includes a main sleeve body, a stop piece installed in the main sleeve body, and a wear-resistant sleeve. The stop piece includes a plate body and a support flange provided at the edge of the plate body. The support flange is supported on the inner surface of the end wall of the main sleeve body to leave a space between the inner surface of the end wall of the main sleeve body and the plate body. The plate body constitutes the baffle. The wear-resistant sleeve is interference or glued installed in the main sleeve body and presses the stop piece.

9. The working medium lubricated plunger assembly of any of claims 1-3, wherein, The pump body includes a main body portion and a plug. The plug hole is a through hole penetrating the main body portion along the extension direction thereof. The plug is installed at the port portion of the plug hole away from the guide sleeve. The elastic thrust structure is provided between the pump body and the plunger. The elastic thrust structure is a spiral spring provided in the plug hole and abutting against the plug and the plunger at both ends, respectively. The end of the plug inserted into the plug hole is provided with a limiting column inserted into the spiral spring and providing radial limitation for the spiral spring.

10. A working medium lubricated radial piston pump comprising a housing, a rotating shaft and piston assemblies arranged around the rotating shaft, the rotating shaft being provided with eccentric structures for pushing the piston assemblies, characterized in that, The plunger assembly is the working medium lubricated plunger assembly according to any one of claims 1-9.

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