Constant-speed universal transmission through shaft type plunger pump or motor

Abstract

The utility model provides a constant-speed universal transmission through shaft type plunger pump or motor, belongs to the technical field of hydraulic transmission, and solves the problem that constant-speed transmission of a piston shoe and a cylinder body of a through shaft type swash plate plunger pump cannot be realized in the prior art. A cylinder body is fixedly sleeved on the main shaft; a cylinder hole is formed in the cylinder body; a plunger is arranged in the cylinder hole; a star-shaped sleeve is sleeved on the main shaft and is provided with a first arc-shaped raceway groove, a turntable assembly is movably sleeved on the star-shaped sleeve, and a second arc-shaped raceway groove is formed in the inner wall of the turntable assembly; a bearing ball is movably arranged between the first arc-shaped raceway groove and the second arc-shaped raceway groove, the plunger is in spherical hinge with the rotating disc assembly, and a swash plate supporting assembly is fixedly arranged in the shell. The main shaft rotates to transmit torque to the rotating disc assembly through the starlike sleeve and the bearing ball, the rotating disc assembly drives the plunger to output the torque, meanwhile, the main shaft transmits the torque to the cylinder body and synchronously drives the plunger to output the torque, and constant-speed transmission of the rotating disc assembly and the cylinder body is achieved.

Description

Technical Field

[0001] The utility model belongs to the technical field of hydraulic transmission, and particularly relates to a constant-velocity universal transmission through-shaft type plunger pump or motor. Background Technique

[0002] As one of the most widely used hydraulic components in modern hydraulic transmission, a pump and a motor act as a pump when serving as an energy device and act as a motor when serving as an actuator. Therefore, to a certain extent, the advanced level of a hydraulic pump represents the level of the hydraulic field. Compared with other types of pumps, a swash-plate axial piston pump or motor has the characteristics of a compact structure and a large flow rate, and is currently the preferred solution for pumps or motors used in construction machinery. Compared with a non-through-shaft type, the pump shaft of a through-shaft type passes through the swash plate, which has a small volume and a light weight. Since it uses small bearings to replace the large bearings of the non-through-shaft type, it is beneficial to increase the rotational speed and reduce the cost. As a rotary displacement pump or motor, the main motion form of a swash-plate axial piston pump or motor is as follows: the main shaft and the cylinder block are connected by a spline and rotate around its own axis at an angular velocity ω; the plunger and the slipper are connected by a ball hinge pair, and under the action of a return mechanism, the slipper moves along an elliptical trajectory in the swash plate plane, and the angular velocity reaches the maximum value ωmax = ω / cosγ and the minimum value ωmin = ωcosγ at the short axis and the long axis respectively; the plunger slipper moves back and forth linearly in the cylinder block hole under the action of the return mechanism, and at the same time rotates around the main shaft axis at an angular velocity ω. For a rotary motion plunger pump, the overturning moment of the rotating assembly is mainly composed of two parts, namely inertia force and centrifugal force. Among them, the inertia force mainly comes from the reciprocating linear motion of the assembly, and the centrifugal force comes from the rotary motion. As the core component of the plunger pump, the main motion mode of the slipper is that the rotary plunger drives the slipper. Since there is a certain angle between the swash plate inclination angle and the axis, to ensure the pump displacement, there must be poor isochronism in the variable-angle transmission of the rotating shaft. Under high-speed conditions, the rotational speed difference of the distributed slippers increases significantly, the unbalanced force increases, resulting in an increase in the overturning moment, an increase in leakage, a decrease in volumetric efficiency, metal contact between the slipper and the swash plate, a decrease in mechanical efficiency, and in severe cases, the pump or motor fails, bringing a series of challenges to the design of the plunger pump or motor under high-speed conditions.

[0003] Regarding the problem of slipper overturning, in existing research and actual products, the improvement of slipper overturning mainly focuses on the optimized design of slipper size, the design of new slippers or return structures, and the surface micro-topography and coating of slippers. Among them, the methods of optimizing size and improving the surface micro-topography and coating of friction pairs generally have obvious effects on products in the initial R & D stage, but the room for performance improvement of mature products is very limited, and it increases the process manufacturing difficulty. In addition, the optimized slippers generally have good working performance only within a limited range of working conditions and it is difficult to meet the reliable operation of the plunger pump under high-speed conditions. The method of new slippers or return structures can directly and effectively improve the anti-overturning ability of slippers, thus avoiding the phenomenon of uneven wear of slippers. The patent with the publication number CN114562437A proposes a swashplate structure, which overcomes the non-uniform angular velocity movement of distributed slippers in the swashplate plane, eliminates the centrifugal force, solves the problems of slipper overturning and uneven wear, and effectively improves the performance of the friction pair under high-speed conditions. The disadvantage is that the integral swashplate realizes the transmission of the main shaft speed and torque through the ball hinge and pin method, there is a speed difference caused by the angle between the swashplate and the axis during rotation, and the resulting unbalanced force acts, increasing the overturning moment and causing the plunger pump to operate unstably. The patent with the publication number CN106032794A adopts a high-speed swashplate rotary pump, which reduces the moment of inertia and improves the dynamic response speed, but still cannot eliminate the non-uniform angular velocity movement of the slippers and the unbalanced force caused by the angle between the swashplate and the axis during rotation.

[0004] To sum up, currently for the technology of constant-velocity universal transmission through-shaft plunger pumps, the swashplate structure mainly solves the problem of distributed slipper overturning, and the rotating swashplate method mainly solves the problem of large moment of inertia, and it is impossible to achieve the function of constant-velocity transmission between the slippers and the plunger cylinder block of the through-shaft swashplate plunger pump. Summary of the Invention

[0005] Aiming at the above problems, the purpose of the present invention is to provide a constant-velocity universal transmission through-shaft plunger pump or motor. When the main shaft rotates, the torque is transmitted to the turntable assembly with a certain angle through the star-shaped sleeve and the load-bearing ball. The turntable assembly drives the plunger to output torque. At the same time, the main shaft transmits the torque to the cylinder block and synchronously drives the plunger to output torque, realizing the constant-velocity transmission between the turntable assembly and the cylinder block in the through-shaft plunger pump or motor, thereby reducing the overturning moment and ensuring the stable operation of the plunger pump or motor.

[0006] The technical solution adopted by the present invention is as follows:

[0007] An isokinetic universal transmission through-shaft type plunger pump or motor, comprising a housing, one end of the housing is provided with a valve plate end cover, an oil suction port and an oil discharge port are opened on the valve plate end cover, a main shaft is rotatably arranged in the housing, a cylinder block that fits against the inner end face of the valve plate end cover is fixedly sleeved on the main shaft, several cylinder holes communicating the two end faces of the cylinder block are arranged circumferentially on the cylinder block, a plunger is movably and sealingly arranged in the cylinder hole, a star-shaped sleeve that rotates synchronously with the main shaft is sleeved on the main shaft, several first arc-shaped raceway grooves are arranged circumferentially on the star-shaped sleeve and the first arc-shaped raceway grooves extend along the axial direction of the main shaft, an inclined turntable assembly is movably sleeved on the star-shaped sleeve, a second arc-shaped raceway groove corresponding to the first arc-shaped raceway groove is arranged on the inner wall of the turntable assembly, a load-bearing ball is movably arranged between the first arc-shaped raceway groove and the second arc-shaped raceway groove, one end of the plunger away from the cylinder block is ball-jointed with the turntable assembly, and an inclined disk support assembly for supporting the turntable assembly is fixedly arranged in the housing.

[0008] Preferably, the turntable assembly includes a driving disk sleeved on the star-shaped sleeve, several ball sockets are arranged on the driving disk, a ball head that cooperates with the ball socket is arranged at the end of the plunger, a pressing plate for preventing the ball head from moving out of the ball socket is installed on the side of the driving disk close to the cylinder block, and a sliding disk that slidably contacts the inclined disk support assembly is installed on the side of the driving disk away from the cylinder block.

[0009] Preferably, a through hole communicating the cylinder hole and the ball socket is arranged in the plunger, a throttle hole is arranged in the ball socket, a communicating groove communicating both sides of the sliding disk is arranged on the sliding disk, and the communicating groove communicates with the throttle hole.

[0010] Preferably, the inclined disk support assembly includes an inclined disk support seat fixed on the housing, and a wear-resistant disk that slidably contacts the turntable assembly is installed on the inclined disk support seat.

[0011] Preferably, a positioning groove is arranged on the inclined disk support seat, and a positioning pin that cooperates with the positioning groove is movably arranged in the housing.

[0012] Preferably, a transmission pin penetrates through the star-shaped sleeve radially, and a mounting hole for the transmission pin to penetrate through is arranged radially on the main shaft.

[0013] Preferably, the mounting hole is strip-shaped, a spring is movably sleeved on the main shaft, and both ends of the spring respectively abut against the cylinder block and the star-shaped sleeve.

[0014] Preferably, the inclination angle of the turntable assembly is 10°.

[0015] Preferably, an oil seal is movably and sealingly sleeved on the main shaft, and the oil seal is located at one end of the housing away from the valve plate end cover.

[0016] Preferably, a ball head is arranged at one end of the plunger located in the cylinder hole.

[0017] To sum up, due to the adoption of the above technical solutions, the beneficial effects of the present utility model are:

[0018] When the main shaft rotates, the torque is transmitted through the star-shaped sleeve and the bearing balls to the turntable assembly that forms a certain angle with it. The turntable assembly drives the plunger to output torque. At the same time, the main shaft transmits the torque to the cylinder block and synchronously drives the plunger to output torque, realizing the constant-speed transmission between the turntable assembly and the cylinder block in the through-shaft type plunger pump or motor, thereby reducing the tipping moment and ensuring the stable operation of the plunger pump or motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as a limitation of the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0020] Figure 1 It is a three-dimensional structure schematic diagram provided by the embodiment of the present invention;

[0021] Figure 2 It is a front view sectional structure schematic diagram provided by the embodiment of the present invention;

[0022] Figure 3 It is Figure 2 an enlarged structure schematic diagram of part A in

[0023] Figure 4 It is a matching schematic diagram of the turntable assembly and the swash plate support assembly provided by the embodiment of the present invention;

[0024] Figure 5 It is a spring installation structure schematic diagram provided by the embodiment of the present invention;

[0025] Figure 6 It is a turntable assembly structure schematic diagram provided by the embodiment of the present invention;

[0026] Figure 7 It is a turntable assembly tilt angle schematic diagram provided by the embodiment of the present invention.

[0027] Description of the drawings: 1 - distribution end cover; 101 - oil suction port; 102 - oil discharge port; 2 - housing; 3 - main shaft; 4 - cylinder block; 5 - spring; 6 - star-shaped sleeve; 7 - turntable assembly; 701 - ball socket; 702 - pressure plate; 703 - drive disk; 704 - sliding disk; 705 - throttle hole; 706 - communication groove; 8 - swash plate support assembly; 801 - wear-resistant disk; 802 - swash plate support seat; 803 - fixing pin; 804 - positioning groove; 9 - second arc-shaped raceway groove; 10 - first arc-shaped raceway groove; 11 - load-bearing ball; 12 - plunger; 13 - through hole; 14 - cylinder hole; 15 - bearing; 16 - oil seal; 17 - transmission pin; 18 - positioning pin; 19 - mounting hole; 20 - retaining ring; 21 - gasket. Detailed implementation manners

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some, but not all, of the embodiments of the present utility model. Usually, the components of the embodiments of the present utility model described and illustrated in the drawings here can be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the present utility model provided in the drawings is not intended to limit the scope of the present utility model to be protected, but merely represents the selected embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the scope of protection of the present utility model.

[0030] In the description of the present utility model, it should be noted that if terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of this application is usually placed. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present utility model.

[0031] The following will be combined with Figures 1-7 to describe the present utility model in detail.

[0032] Embodiment

[0033] A constant-velocity universal transmission through-shaft type piston pump or motor, comprising a housing 2, one end of the housing 2 is provided with a valve plate end cover 1 (the valve plate end cover 1 is fixed to the housing 2 by screws), the valve plate end cover 1 is provided with an oil suction port 101 and an oil discharge port 102, a main shaft 3 is rotatably arranged in the housing 2, a cylinder block 4 which is in fit with the inner end face of the valve plate end cover 1 is fixedly sleeved on the main shaft 3, several cylinder holes 14 communicating with both end faces of the cylinder block 4 are arranged along the circumferential direction of the cylinder block 4, pistons 12 are movably and sealingly arranged in the cylinder holes 14, a star-shaped sleeve 6 which rotates synchronously with the main shaft 3 is sleeved on the main shaft 3, several first arc-shaped raceway grooves 10 are arranged along the circumferential direction of the star-shaped sleeve 6 and the first arc-shaped raceway grooves 10 extend along the axial direction of the main shaft 3, an inclined turntable assembly 7 is movably sleeved on the star-shaped sleeve 6, a second arc-shaped raceway groove 9 corresponding to the first arc-shaped raceway groove 10 is arranged on the inner wall of the turntable assembly 7, load-bearing balls 11 are movably arranged between the first arc-shaped raceway groove 10 and the second arc-shaped raceway groove 9, one end of the piston 12 far from the cylinder block 4 is ball-jointed with the turntable assembly 7, and an inclined disk support assembly 8 for supporting the turntable assembly 7 is fixedly arranged in the housing 2.

[0034] When the main shaft 3 rotates, the torque is transmitted to the turntable assembly 7 which has a certain angle with it through the star-shaped sleeve 6 and the load-bearing balls 11. The turntable assembly 7 drives the piston 12 to output torque. At the same time, the main shaft 3 transmits the torque to the cylinder block 4 and synchronously drives the piston 12 to output torque, realizing the constant-velocity transmission between the turntable assembly 7 and the cylinder block 4 in the through-shaft type piston pump or motor. Among them, the inclined disk support assembly 8 provides sliding support for the turntable assembly 7 to ensure the inclined rotation of the turntable assembly 7.

[0035] After the main shaft 3 rotates, while driving the piston 12 to rotate, the piston 12 reciprocates, and then sucks hydraulic oil from the oil suction port 101 into the cylinder hole 14. During the rotation of the cylinder block 4, the end face of the valve plate end cover 1 is used to seal the cylinder hole 14. When the cylinder hole 14 is aligned with the oil discharge port 102, the piston 12 will push out the hydraulic oil in the cylinder hole 14, thus realizing the transportation of hydraulic oil by the piston pump or motor. Among them, the hydraulic oil in the cylinder hole 14 can lubricate the gap between the cylinder block 4 and the valve plate end cover 1 to reduce wear.

[0036] The turntable assembly 7 includes a driving disk 703 sleeved on the star-shaped sleeve 6. A plurality of ball sockets 701 are arranged on the driving disk 703. The end of the plunger 12 is provided with a ball head that cooperates with the ball socket 701. A pressing plate 702 for preventing the ball head from moving out of the ball socket 701 is installed on the side of the driving disk 703 close to the cylinder block 4. A sliding disk 704 that is in sliding contact with the swash plate support assembly 8 is installed on the side of the driving disk 703 away from the cylinder block 4. The pressing plate (702), the driving disk 703, and the sliding disk 704 are fixed by screws to form an integral body; a second arc-shaped raceway groove 9 is arranged on the driving disk 703. The star-shaped sleeve 6 drives the driving disk 703 to rotate through the load-bearing balls 11. The plunger 12 forms a ball hinge through the cooperation of the ball head and the ball socket 701, so as to perform a reciprocating motion during the rotation of the driving disk 703.

[0037] A through hole 13 communicating the cylinder hole 14 and the ball socket 701 is arranged in the plunger 12. A throttle hole 705 is arranged in the ball socket 701. A communication groove 706 communicating both sides of the sliding disk 704 is arranged on the sliding disk 704. The communication groove 706 communicates with the throttle hole 705. A small part of the hydraulic oil in the cylinder hole 14 can enter the ball socket 701 through the through hole 13 of the plunger 12 for lubrication, reducing the wear between the ball socket 701 and the ball head of the plunger 12. And the hydraulic oil will also enter the gap between the sliding disk 704 and the swash plate support assembly 8 through the throttle hole 705 and the communication groove 706, thereby reducing the wear between the sliding disk 704 and the swash plate support assembly 8 and ensuring the stable rotation of the turntable assembly 7 relying on the swash plate support assembly 8.

[0038] The swash plate support assembly 8 includes a swash plate support seat 802 fixed on the housing 2. A wear-resistant disk 801 that is in sliding contact with the turntable assembly 7 is installed on the swash plate support seat 802. The wear-resistant disk 801 and the swash plate support seat 802 are fixedly connected by a fixing pin 803. The wear-resistant disk 801 has good wear resistance, which can reduce the wear of the wear-resistant disk 801.

[0039] A positioning groove 804 is arranged on the swash plate support seat 802. A positioning pin 18 that cooperates with the positioning groove 804 is movably arranged in the housing 2. The cooperation of the positioning pin 18 and the positioning groove 804 fixes the position of the swash plate support seat 802, so as to keep the swash plate support seat 802 stationary, and at the same time it is also convenient for subsequent disassembly.

[0040] A transmission pin 17 penetrates the star-shaped sleeve 6 radially and movably. An installation hole 19 for the transmission pin 17 to penetrate is radially opened on the main shaft 3. The star-shaped sleeve 6 is fixed on the main shaft 3 through the transmission pin 17, so as to rotate synchronously with the main shaft 3.

[0041] The mounting hole 19 is strip-shaped. A spring 5 is movably sleeved on the main shaft 3, and both ends of the spring 5 are respectively abutted against the cylinder block 4 and the star-shaped sleeve 6. After the plunger pump or motor has been used for a period of time, its wear-resistant disc 801 and sliding disc 704 will have a certain degree of wear. In order to maintain the stable rotation of the sliding disc 704, it is necessary for the sliding disc 704 to always fit on the wear-resistant disc 801. Therefore, the strip-shaped mounting hole 19 and the spring 5 are provided. After the wear-resistant disc 801 and the sliding disc 704 are worn, the spring 5 will push the star-shaped sleeve 6 towards the wear-resistant disc 801 to achieve the axial compensation of the star-shaped sleeve 6. Two gaskets 21 that abut against the end of the spring 5 are movably sleeved on the main shaft 3. A retaining ring 20 is clamped in the cylinder block 4, and the retaining ring 20 is sleeved on the main shaft 3 to abut against one of the gaskets 21 of the spring 5. From Figure 5 it can be seen that the inner diameter of the retaining ring 20 is smaller than the outer diameter of the gasket 21.

[0042] As Figure 7 shown, the inclination angle of the turntable assembly 7 is 10°. At this angle, the turntable assembly 7 can better transmit torque to the plunger 12.

[0043] An oil seal 16 is movably and sealingly sleeved on the main shaft 3, and the oil seal 16 is located at one end of the housing 2 away from the port plate 1. The oil seal 16 seals the gap between the main shaft 3 and the housing 2 to prevent the oil in the housing 2 from leaking. A retaining ring 20 is also clamped on the housing 2 outside the oil seal 16, and this retaining ring 20 prevents the oil seal 16 from moving out of the housing 2.

[0044] A ball head is provided at one end of the plunger 12 located in the cylinder hole 14. A line seal is formed between the plunger 12 and the cylinder hole 14 through the ball head, reducing the wear of the plunger 12 and the cylinder hole 14.

[0045] Bearings 15 are provided at both ends of the main shaft 3, and are respectively located on the port plate 1 and the housing 2 to ensure the stable rotation of the main shaft 3.

[0046] The load-bearing ball 11 is one of steel balls, ceramic balls or other materials that can bear loads on the spherical surface without damage. In the present utility model, it is set as a steel ball.

[0047] The above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. For those skilled in the art, the present utility model can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A constant velocity universal transmission through-axis plunger pump or motor, comprising a housing (2), one end of the housing (2) being provided with a distribution end cover (1), the distribution end cover (1) being provided with an oil suction port (101) and an oil discharge port (102), characterized in that: A main shaft (3) is rotatably arranged in the housing (2); a cylinder body (4) is fixedly sleeved on the main shaft (3) and is fitted with the inner end surface of the distribution end cover (1); the cylinder body (4) is provided with a plurality of cylinder holes (14) in the circumferential direction and are connected to the two end surfaces of the cylinder body (4); a plunger (12) is movably sealed in the cylinder hole (14); a star sleeve (6) is sleeved on the main shaft (3) and is synchronously rotated with the main shaft (3); the star sleeve (6) is provided with a plurality of first arc-shaped rolling grooves (10) in the circumferential direction, and the first arc-shaped rolling grooves (10) are arranged along the main shaft The star-shaped sleeve (3) is axially extended, a movable sleeve on the star-shaped sleeve (6) is provided with an inclined turntable assembly (7), an inner wall of the turntable assembly (7) is provided with a second arc-shaped rolling groove (9) corresponding to the first arc-shaped rolling groove (10), a bearing ball (11) is movably provided between the first arc-shaped rolling groove (10) and the second arc-shaped rolling groove (9), an end of the plunger (12) away from the cylinder body (4) is ball-jointed with the turntable assembly (7), and an inclined plate support assembly (8) for supporting the turntable assembly (7) is fixedly provided in the housing (2).

2. A constant velocity universal transmission through-axle plunger pump or motor according to claim 1, characterized in that: The rotating disk assembly (7) comprises a driving disk (703) sleeved on a star-shaped sleeve (6), a plurality of ball sockets (701) being arranged on the driving disk (703), a ball head cooperating with the ball sockets (701) being arranged at the end of the plunger (12), a pressure plate (702) for preventing the ball head from moving out of the ball sockets (701) being installed on the side of the driving disk (703) close to the cylinder body (4), and a sliding disk (704) in sliding contact with the swash plate support assembly (8) being installed on the side of the driving disk (703) away from the cylinder body (4).

3. A constant velocity universal transmission through-axle plunger pump or motor according to claim 2, characterized in that: The plunger (12) is provided with a through hole (13) connecting the cylinder hole (14) and the ball socket (701), the ball socket (701) is provided with a throttle hole (705), the sliding plate (704) is provided with a connecting groove (706) connecting the two sides of the sliding plate (704), and the connecting groove (706) is in communication with the throttle hole (705).

4. A constant velocity universal transmission through-axle plunger pump or motor according to claim 1, characterized in that: The swash plate support assembly (8) comprises a swash plate support seat (802) fixed on the housing (2), and a wear-resistant plate (801) is mounted on the swash plate support seat (802) and is in sliding contact with the rotating plate assembly (7).

5. A constant velocity universal transmission through-axle plunger pump or motor according to claim 4, characterized in that: The swash plate support seat (802) is provided with a positioning groove (804), and a positioning pin (18) cooperating with the positioning groove (804) is movably provided in the housing (2).

6. A constant velocity universal transmission through-axle plunger pump or motor according to claim 1, characterized in that: A transmission pin (17) is movably penetrated radially on the star-shaped sleeve (6), and a mounting hole (19) for the transmission pin (17) to penetrate is opened radially on the main shaft (3).

7. A constant velocity universal transmission through-axle plunger pump or motor according to claim 6, characterized in that: The mounting hole (19) is in the shape of a strip, and a spring (5) is arranged on the movable sleeve on the main shaft (3), and the two ends of the spring (5) are respectively abutted against the cylinder body (4) and the star-shaped sleeve (6).

8. A constant velocity universal transmission through-axle plunger pump or motor according to claim 1, characterized in that: The inclination angle of the turntable assembly (7) is 10°.

9. A constant velocity universal transmission through-axle plunger pump or motor according to claim 1, characterized in that: The movable sealing sleeve on the main shaft (3) is provided with an oil seal (16), and the oil seal (16) is located at one end of the housing (2) away from the distribution end cover (1).

10. A constant velocity universal transmission through-axle plunger pump or motor according to claim 1, characterized in that: A ball head is provided at one end of the plunger (12) located in the cylinder hole (14).

Images