A floating swash plate type axial piston pump based on rotation driving of a backshifting disc

Abstract

The application discloses a floating swash plate type axial plunger pump based on return disc rotary drive, comprising a pump body, the pump body has a valve plate, a cylinder body, a return disc, a rotary disc and a swash plate connected in series by a main shaft, the cylinder body, the return disc and the rotary disc make synchronous rotary motion with the main shaft, one end of multiple slide shoes in the return disc is hinged with a ball head at the end of a plunger in the cylinder body, the other end of the slide shoes is in contact with the rotary disc, static pressure bearings are formed between the slide shoes and the rotary disc, between the rotary disc and the swash plate and between the cylinder body and the valve plate, the slide shoes drive the return disc to rotate, the return disc drives the rotary disc to synchronously rotate based on a connecting pin, thus, the slide shoes have no relative sliding motion relative to the rotary disc, the friction power loss of the slide shoe pair is eliminated, the risk of overturning and eccentric wear of the slide shoes caused by high-speed centrifugal force is reduced, the rotary disc replaces the dispersed slide shoe pair, which is beneficial to the realization of high speed of the pump, and the valve plate is designed with a static pressure bearing structure, the friction and lubrication performance at low speed is improved, and the friction and wear at low speed is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of plunger pump, in particular to a floating swash plate type axial plunger pump based on return disc rotation driving. BACKGROUND

[0002] Hydraulic transmission has the advantages of high power density, convenient control and excellent dynamic performance compared with traditional mechanical transmission, and is widely used in modern industrial system, especially in engineering machinery. So far, most of the engineering machinery in China adopts hydraulic transmission technology. As one of the core components of the hydraulic system, the axial plunger pump is the core component of the entire hydraulic system and the power source component of the entire hydraulic system. It has the advantages of high transmission power, long service life, simple control variable, convenient variable, small size, etc. Most of the hydraulic systems of engineering machinery in China use plunger pumps as the power source of the entire hydraulic system. Therefore, analyzing and researching the characteristics of the axial plunger pump play an important role in improving the performance of the entire hydraulic system.

[0003] In recent years, with the continuous development of China's mechanical industry, the performance of the plunger pump has been put forward with more stringent requirements. The demand for high pressure, high speed and high performance of the hydraulic system is increasingly urgent, and it is urgent to solve the problem of wear and tear of the axial plunger pump. As important friction pairs of swash plate plunger pump, the friction force generated by the two friction pairs is an important part of the power loss of swash plate plunger pump. On the one hand, if the lubrication condition is poor, the gap between the friction pair elements is too small or even in long-term solid contact, it is easy to accumulate heat, which may reduce the service life and increase mechanical loss, or even directly sinter and damage. On the other hand, if the gap between the friction elements is too large, the sealing effect of the friction pair will be reduced, and the leakage will increase rapidly, thereby reducing the volumetric efficiency of the entire pump.

[0004] With the development of engineering machinery electrification, the axial plunger pump will need to achieve higher working speed. When the axial plunger pump rotates at high speed, the existing axial plunger pump shoe structure is prone to overturning and eccentric wear under the action of centrifugal force generated by high-speed rotation, which is a typical failure mode of axial plunger pump. At the same time, the existing axial plunger pump shoe structure is a dispersed structure, which generally contains 9 shoes in one pump. The dispersed shoes reduce the contact area of the shoes and the swash plate surface, increase the contact stress and PV value of the shoe pair, and are not conducive to the realization of high speed of the pump. The 9 shoes prone to overturning and eccentric wear simultaneously rotate at high speed relative to the swash plate surface, which increases the friction power loss and leakage loss of the shoe pair, and increases the failure point. Once one of the shoes fails, the entire pump will be damaged.

[0005] The electric transformation of construction machinery requires the internal friction pair of the axial piston pump to improve the friction and lubrication performance under low speed working condition. The current axial piston pump flow distribution pair is generally not designed with static pressure supporting structure, which leads to insufficient lubricating oil film formation, severe friction, large friction power loss and easy wear failure of the flow distribution pair under low speed working condition. SUMMARY

[0006] The application provides a floating swash plate type axial piston pump based on the rotation driving of a return plate to solve the problems caused by the dispersed shoe structure in the swash plate type axial piston pump and improve the friction and lubrication performance of the flow distribution pair under low speed working condition through the static pressure supporting structure.

[0007] To achieve the above purpose, the technical scheme adopted by the application is as follows:

[0008] A floating swash plate type axial piston pump based on the rotation driving of a return plate, comprising a pump body (14), a main shaft (1) arranged in the pump body (14), and a flow distribution plate (12), a cylinder body (11), a rotating plate (6) and a swash plate (5) arranged in sequence and in a straight line, wherein the center of the end face of the one end of the cylinder body (11) towards the rotating plate (6) is provided with a spherical hinge (8), the cylinder body (11) is provided with a plurality of cylinder holes (17), each cylinder hole (17) is slidably provided with a piston (10), one end of each piston (10) is arranged to pass through the one end of the cylinder body (11) towards the end face of the rotating plate (6), the end face of the one end of the cylinder body (11) towards the flow distribution plate (12) is provided with a plurality of oil passage orifices (21) corresponding to the cylinder holes (17), the flow distribution plate (12) is provided with a plurality of flow distribution holes penetrating the flow distribution plate (12), the one side of the rotating plate (6) towards the cylinder body (11) is provided with a return plate (9), the return plate (9) is provided with a plurality of connecting pins (16), one end of each connecting pin (16) is connected to the rotating plate (6);

[0009] The return plate (9) is provided with a plurality of through holes, each through hole is provided with a shoe (7) penetratingly arranged therein, one end of each shoe (7) towards the cylinder body (11) is provided with a ball socket, one end of each piston (10) passing through the cylinder body (11) is hingedly connected to the ball socket of the shoe (7) in a one-to-one correspondence, and the other end of each shoe (7) is in contact with the corresponding surface of the rotating plate (6);

[0010] The return disc (9) also keeps contact with the ball hinge (8) through its center through hole, the main shaft (1) penetrates the center of the distribution disc (12), the center of the cylinder body (11), the center of the ball hinge (8), the center of the rotating disc (6), and the center of the swash plate (5) in turn, and the main shaft (1) is connected with the cylinder body (11) and the ball hinge (8), so that when the main shaft (1) rotates, the cylinder body (11) and the ball hinge (8) rotate as a whole, and then the return disc (9) rotates and each shoe (7) and plunger (10) rotates, the return disc (9) rotates through the connecting pin (16) to drive the rotating disc (6) to rotate, and the rotating disc (6) and the swash plate (5) are in clearance fit on the side, that is, they are not in contact in the radial direction.

[0011] Each plunger (10) is provided with an oil guide through hole, one end of the oil guide through hole is communicated to the corresponding cylinder hole (17), and the other end of the oil guide through hole is communicated to the ball socket in the corresponding shoe (7), one end face of each shoe (7) in contact with the rotating disc (6) is provided with a static pressure oil chamber (26), and each static pressure oil chamber (26) is communicated with the ball socket in the corresponding shoe (7), the oil in the cylinder hole (17) in the cylinder body (11) from the distribution disc (12) enters the static pressure oil chamber (26) of the shoe (7) through the oil guide through hole of the plunger (10) and the ball socket of the shoe (7), so that the oil forms a first static pressure support between each shoe (7) and the rotating disc (6).

[0012] Further, the end face of the cylinder body (11) facing the distribution disc (12) is in clearance fit with the distribution disc (12), the end face of the cylinder body (11) facing the distribution disc (12) is provided with an oil storage groove (25) corresponding to each oil passage (21), and the oil storage groove (25) is communicated with the corresponding oil passage (21) through a damping hole (24), part of the oil in the oil passage (21) enters the oil storage groove (25) through the damping hole (24), and then flows into the gap between the cylinder body (11) and the distribution disc (12) to form a second static pressure support.

[0013] Further, the rotating disc (6) and the swash plate (5) are in clearance fit, the rotating disc (6) is provided with an oil guide channel (18) corresponding to each shoe (7), one end of the oil guide channel (18) is communicated with the static pressure oil chamber (26) of the corresponding shoe (7), and the other end of the oil guide channel (18) is communicated to the gap between the rotating disc (6) and the swash plate (5), so that the oil in the static pressure oil chamber (26) flows into the oil storage chamber (19) between the rotating disc (6) and the swash plate (5) through the oil guide channel (18) to form a third static pressure support.

[0014] Further, one side of the swash plate (6) corresponding to each oil guide hole (18) is respectively provided with an oil storage chamber (19), and the other end of the oil guide hole (18) is respectively communicated to the corresponding oil storage chamber (19), so that the oil flows into the gap between the swash plate (5) and the swash plate (6) through the oil storage chamber (19) to form a third static pressure bearing.

[0015] Further, one side of the swash plate (6) corresponding to each oil guide hole (18) is respectively provided with an oil storage chamber (19), and the other end of the oil guide hole (18) is respectively communicated to the corresponding oil storage chamber (19), so that the oil flows into the gap between the swash plate (5) and the swash plate (6) through the oil storage chamber (19) to form a third static pressure bearing.

[0016] The swash plate (6) of the present application is provided with an oil guide hole (18) in the middle of the oil storage chamber on the assembly surface, and the hydraulic oil in the bottom surface static pressure oil chamber (26) of the shoe (7) flows into the gap between the swash plate (6) and the swash plate (5) through the oil guide hole (18), realizing complete static pressure bearing of the swash plate (6). Since the shoe (7) drives the return plate (9) to rotate through the neck portion, the return plate (9) drives the floating swash plate (6) of the complete static pressure bearing to rotate through the connecting pin (16), so that there is no relative sliding movement between the shoe (7) and the swash plate (6) during the operation of the axial piston pump, thereby completely eliminating the overturning and eccentric wear phenomenon of the shoe (7) caused by centrifugal force, and eliminating the friction power loss of the shoe pair. The present application converts the nine dispersed shoe pairs in the existing axial piston pump into an integral swash plate rotating pair between the swash plate (6) and the swash plate (5), and the integral swash plate rotating pair rotates around the central axis on the swash plate surface, the radial centrifugal force is offset, the stability and reliability of the rotation are increased, the contact area between the swash plate (6) and the swash plate (5) is significantly increased compared to the total contact area of the nine dispersed shoe pairs of the existing axial piston pump, and the PV value is significantly reduced, which is beneficial to the realization of high speed of the pump.

[0017] The cylinder (11) and the distribution plate (12) are provided with an oil guide hole (21) and an oil storage groove (25) on the distribution surface, part of the hydraulic oil in the oil guide hole (21) enters the oil storage groove (25) through the fixed damping hole (24), and the static pressure bearing is formed under the cooperation of the variable gap between the distribution plate (12) and the cylinder (11), which can improve the friction and lubrication performance of the distribution pair of the axial piston pump under low speed working condition, and reduce the friction and wear under low speed. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a kind of integral assembly half-section schematic view of the floating swash plate type axial piston pump based on the rotation driving of return plate of the present application.

[0019] Figure 2 It is a kind of integral assembly partial cross-sectional view of the floating swash plate type axial piston pump based on the rotation driving of return plate of the present application.

[0020] Figure 3It is an assembly explosion drawing (shell removal) of a floating swash plate type axial piston pump based on a return plate rotary drive of the application.

[0021] Figure 4 It is a partial assembly structure sectional view of a cylinder body and a flow distribution disc of a floating swash plate type axial piston pump based on a return plate rotary drive of the application.

[0022] Figure 5 It is a rear view of a cylinder body structure of a floating swash plate type axial piston pump based on a return plate rotary drive of the application.

[0023] Figure 6 It is a partial assembly structure half-sectional view of a sliding shoe, a return plate, a connecting pin and a rotary disc of a floating swash plate type axial piston pump based on a return plate rotary drive of the application.

[0024] Figure 7 It is a front view of a rotary disc structure of a floating swash plate type axial piston pump based on a return plate rotary drive of the application.

[0025] Figure 8 It is a rear view of a return plate structure of a floating swash plate type axial piston pump based on a return plate rotary drive of the application.

[0026] Figure 9 It is a half-sectional view of a cylinder body structure of a floating swash plate type axial piston pump based on a return plate rotary drive of the application.

[0027] Figure 10 It is Figure 6 A partial enlarged view of position A. DETAILED DESCRIPTION

[0028] The application will be further described below in combination with the drawings and examples.

[0029] As Figure 1 , Figure 2 , Figure 3 shown, the embodiment discloses a floating swash plate type axial piston pump based on a return plate rotary drive, which comprises a pump body 14, a cavity opening of an inner cavity of the pump body 14 is arranged on a front side of the pump body 14, a front end cover 2 is installed in the cavity opening, and a rear side cover 13 is connected to a rear side of the pump body 14. The inner cavity of the pump body 14 is sequentially provided with a bearing 3, a base 4, a swash plate 5, a rotary disc 6, a return plate 9, a cylinder body 11 and a flow distribution disc 12 from back to front of the front end cover 2. Among them:

[0030] The axial direction of the front end cover 2, the bearing 3 and the base 4 is the front-rear direction. The outer ring of the bearing 3 is fixed to the rear side of the front end cover 2, and the front side of the base 4 is fixedly connected to the rear end of the outer ring of the bearing 3. The swash plate 5 is installed on the rear end of the base 4 towards the front side of the base 4, and the central axis of the swash plate 5 is at an acute angle with the front-rear direction. The pump body 14 is also provided with a variable lever 15, which is connected to the edge of the swash plate 5 through a spherical hinge. The variable lever 15 can adjust the inclination angle of the swash plate 5 by pushing the swash plate.

[0031] The swivel plate 6 is in the same inclined posture as the swash plate 5, that is, the central axis of the swivel plate 6 is at the same acute angle with the front-rear direction. The front end surface of the swivel plate 6 is opposite to the rear end surface of the swash plate 5 with a gap. The return plate 9 is in the same inclined posture as the swivel plate 6, that is, the central axis of the return plate 9 is at the same acute angle with the front-rear direction. The front end surface of the return plate 9 is opposite to the rear end surface of the swivel plate 6 with a certain gap.

[0032] As shown in Figure 6 , Figure 8 , the return plate 9 is provided with nine pin mounting holes 22, which are uniformly distributed around the center of the return plate 9. Each pin mounting hole 22 is provided with a connecting pin 16, and the gap between the pin mounting hole 22 and the corresponding connecting pin 16 is matched. Each connecting pin 16 is inserted into the corresponding hole of the swivel plate 6 towards the front end of the swivel plate 6, so that the return plate 9 and the swivel plate 6 are connected as a whole through the connecting pin 16.

[0033] The return plate 9 is also provided with a plurality of through holes around the outer periphery of the ring formed by the pin mounting holes 22. Each through hole is uniformly distributed around the center of the return plate 9. Each through hole is provided with a sliding shoe 7. The sliding shoe 7 is provided with a spherical socket towards the rear end of the cylinder body 11. The sliding shoe 7 is in contact with the rear end surface of the swivel plate 6 towards the front end of the swivel plate 6.

[0034] The axial direction of the cylinder body 11 is the front-rear direction. The cylinder body 11 is connected to the spherical hinge 8 at the center of the front end surface of the swivel plate 6. The return plate 9 is sleeved on the spherical hinge 8 through the central through hole. The central through hole of the cylinder body 11 is connected to the main shaft 1 through the spline 23. The cylinder body 11 is provided with a plurality of cylinder holes 17 with the axial direction being the front-rear direction. Each cylinder hole 17 is uniformly distributed around the central axis of the cylinder body 11. Each cylinder hole 17 is slidably provided with a plunger 10. The front end of each plunger 10 is inserted into the spherical socket at the rear end of each sliding shoe 7 from the cylinder body 11 towards the front end surface of the swivel plate 6.

[0035] A center spring 27 is arranged between the cylinder body 11 and the ball hinge 8, one end of the center spring 27 exerts a spring force on the cylinder body 11, so that the cylinder body 11 is pressed towards the valve plate 12, the other end of the center spring 27 exerts a spring force on the ball hinge 8, so that the ball hinge 8 is pressed towards the return plate 9, the return plate 9 is further pressed towards the sliding shoe 7, the sliding shoe 7 is further pressed towards the rotating plate 6, and finally the spring force is transmitted to press the rotating plate 6 towards the swash plate 5. The center spring 27 provides an initial pre-pressing and pre-sealing force for the valve plate pair formed between the cylinder body 11 and the valve plate 12, the sliding shoe pair formed between the sliding shoe 7 and the rotating plate 6, and the rotating plate pair formed between the rotating plate 6 and the swash plate 5 before the pump starts and before the pressure is established.

[0036] The axial direction of the valve plate 12 is the front-rear direction, and the valve plate 12 is provided with a plurality of valve holes penetrating through the valve plate 12 in the front-rear direction, the valve holes being used to communicate the cylinder holes 17 and the oil inlet and outlet ports of the pump body. The rear end surface of the cylinder body 11 is in clearance fit with the front end surface of the valve plate 12, and the rear end surface of the cylinder body 11 is provided with an oil passage hole 21 corresponding to the position of each cylinder hole 17, the oil passage hole 21 being in communication with the corresponding cylinder hole 17.

[0037] The inner cavity of the pump body 14 is further provided with a main shaft 1 in the axial direction of the front-rear direction, the main shaft 1 penetrates through the center of the front end cover 2, the inner ring of the bearing 3, the center of the base 4, the center of the swash plate 5, the center of the rotating plate 6, the center of the ball hinge 8, the center of the cylinder body 11, and the center of the valve plate 12, and the main shaft 1 is connected with the cylinder body 11 and the ball hinge 8 through spline connection, and the main shaft 1 is fixedly connected with the inner ring of the bearing 3. Thus, when the main shaft 1 rotates, the cylinder body 11 and the ball hinge 8 rotate as a whole, each plunger 10 installed in the cylinder hole 17 rotates synchronously with the cylinder body 11, each sliding shoe 7 connected with each plunger 10 rotates synchronously, the sliding shoe 7 drives the return plate 9 to rotate synchronously through the neck portion of the sliding shoe 7, and the return plate 9 rotates synchronously with the rotating plate 6 through the connecting pin 16, since the connecting pin 16 only bears radial force, it drives the rotating plate 6 to rotate without affecting the assembly relationship and dynamic relationship between the return plate 9 and the sliding shoe 7. There is a certain gap between the inner side surface of the swash plate 5 and the outer side surface of the rotating plate 6, i.e. they are not in radial contact. The rotating plate 6 rotates around the central shaft driven by the return plate 9, the rotating plate 6 rotates synchronously with the return plate 9, and there is no relative sliding movement between the sliding shoe 7 and the rotating plate 6.

[0038] As Figure 4 , Figure 5 , Figure 9As shown, the rear end face of the cylinder block 11 is provided with oil storage grooves 25 corresponding to the inner and outer sides of each oil passage 21, and each oil passage 21 is in communication with the corresponding two oil storage grooves 25 through a damping hole 24. Each plunger 10 is provided with an oil guide hole, the rear end of which is in communication with the corresponding cylinder bore 17 in the cylinder block 11, and the front end of which is in communication with the ball socket in the corresponding sliding shoe 7. The front end face of each sliding shoe 7 in contact with the swash plate 6 is provided with a static pressure oil chamber 26, and each static pressure oil chamber 26 is in communication with the ball socket in the corresponding sliding shoe 7.

[0039] As shown in Figure 7 , Figure 10 The swash plate 6 is provided with an oil guide channel 18 corresponding to each sliding shoe 7, and the front end face of the swash plate 6 facing the swash plate 5 is provided with an oil storage chamber 19 corresponding to each oil guide channel 18. The rear end of the oil guide channel 18 is in communication with the static pressure oil chamber 26 of the corresponding sliding shoe 7, and the front end of the oil guide channel 18 is in communication with the oil storage chamber 19 on the front end face of the swash plate 6. The front end face of the swash plate 6 is also provided with two pressure relief ring grooves 20, one of which is located at the edge of the front end face of the swash plate 6, and the other of which is located in the annular space formed by the oil storage chambers 19.

[0040] As an improvement of the present embodiment, the oil storage chamber 19 can also be provided on the rear end face of the swash plate 5 facing the swash plate 6, and the pressure relief ring groove 20 can also be provided on the rear end face of the swash plate 5 facing the swash plate 6.

[0041] In the present embodiment, the oil enters the oil passage 21 of the cylinder block 11 through the oil distribution hole of the oil distribution plate 12, and then enters each cylinder bore 17 of the cylinder block 11, or the oil flowing out of the cylinder bore 17 enters the oil distribution hole of the oil distribution plate 12 through the oil passage 21. In this process, part of the oil in the oil passage 21 flows into the oil storage groove 25 through the damping hole 24, and under the action of the variable gap cooperation between the rear end face of the cylinder block 11 and the front end face of the oil distribution plate 12, a second static pressure support is formed. The second static pressure support can improve the friction lubrication performance of the oil distribution pair of the axial plunger pump under low speed conditions, and reduce the friction and wear under low speed conditions.

[0042] The oil entering the cylinder bore 17 enters the static pressure oil chamber 26 of the sliding shoe 7 through the oil guide hole of the plunger 10 and the ball socket of the sliding shoe 7, and thus the oil forms a first static pressure support between each sliding shoe 7 and the swash plate 6. The oil entering the static pressure oil chamber 26 flows into the oil storage chamber 19 on the front end face of the swash plate 6 through the oil guide channel 18 in the swash plate 6, and cooperates with the oil discharge ring groove 20 to form a third static pressure support between the swash plate 6 and the swash plate 5. The first static pressure support and the third static pressure support cooperate to achieve complete static pressure support of the swash plate 6.

[0043] The main shaft 1 drives the cylinder body 11 and the plunger 10 under the drive of the prime mover. When the cylinder body 11 rotates, the plunger 10 gradually extends outward in the cylinder body 11 in a half circle from bottom to top, so that the volume of the sealed working chamber of the cylinder hole 17 of the cylinder body 11 is continuously increased, a local vacuum is generated, and hydraulic oil is sucked through the flow distribution hole on the flow distribution disc 12; on the contrary, when the plunger 10 gradually retracts into the cylinder body in a half circle from top to bottom, the volume of the sealed working chamber of the cylinder hole 17 is continuously reduced, and the oil is pressed outwards through the oil passage hole 21 connected to the rear end of the cylinder hole 17 and the flow distribution hole on the flow distribution disc 12.

[0044] When the cylinder body 11 rotates one circle, each plunger 10 reciprocates once, and the oil is sucked and pressed once. Part of the oil in the oil passage hole 21 of the cylinder body 11 flows into the oil storage groove 25 through the damping hole 24, and the variable gap between the cylinder body 11 and the flow distribution disc 12 cooperates to form a second static pressure support at the flow distribution pair.

[0045] The sliding shoe 7 connected with the plunger 10 drives the return disc 9 to rotate around the center line, and the return disc 9 drives the rotating disc 6 to rotate synchronously through the connecting pin 16, so that there is no relative revolution sliding motion between the sliding shoe 7 and the rotating disc 6. The oil in the cylinder hole 17 enters the static pressure oil chamber 26 of the sliding shoe 7 through the oil guide hole of the plunger and the ball socket of the sliding shoe 7, thereby forming a first static pressure support between the sliding shoe 7 and the rotating disc 6.

[0046] The oil in the static pressure oil chamber 26 enters the oil storage chamber 19 of the rotating disc 6 through the oil guide hole 18 in the rotating disc 6, and at this time, the third static pressure support is formed between the rotating disc 6 and the swash plate 5.

[0047] Since the sliding shoe 7 drives the return disc 9 to rotate through the neck portion, and the return disc 9 drives the floating rotating disc 6 to rotate through the connecting pin 16, there is no relative revolution motion between the sliding shoe 7 and the rotating disc 6 when the axial plunger pump works, so that the overturning and eccentric wear phenomenon of the sliding shoe 7 caused by centrifugal force is completely eliminated, the friction power loss of the sliding shoe pair is eliminated, the nine dispersed sliding shoe pairs in the existing axial plunger pump are converted into an integral rotating disc rotating pair between the rotating disc 6 and the swash plate 5, the integral rotating disc rotating pair rotates around the central axis on the swash plate surface, the radial centrifugal force is offset, the stability and reliability of the rotation are increased, the contact area between the rotating disc 6 and the swash plate 5 is significantly increased compared with the total contact area of the nine dispersed sliding shoe pairs of the existing axial plunger pump, and the PV value is significantly reduced, which is beneficial to the realization of high speed of the pump.

[0048] The preferred embodiments of the present application are described in detail above with reference to the accompanying drawings, and the embodiments described in the present application are merely preferred embodiments of the present application, and are not intended to limit the concept and scope of the present application. In the above specific embodiments, various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction, and such combination should also be considered as disclosed in the present application, as long as it does not deviate from the concept of the present application. In order to avoid unnecessary repetition, various possible combinations are not described again in the present application.

[0049] The present application is not limited to the specific details of the above-described embodiments, and various modifications and improvements to the technical solutions of the present application made by those skilled in the art within the scope of the technical concept of the present application and without departing from the design concept of the present application should fall within the protection scope of the present application. The technical content claimed by the present application has been fully recorded in the claims.

Claims

1. A floating swash plate type axial piston pump based on backhaul disc rotation drive, comprising a pump body (14), a main shaft (1) arranged in the pump body (14), and a valve plate (12), a cylinder block (11), a rotating disc (6) and a swash plate (5) arranged in sequence along a straight line, wherein a spherical hinge (8) is arranged at the center of an end face of the cylinder block (11) facing the rotating disc (6), a plurality of cylinder holes (17) are arranged in the cylinder block (11), and a piston (10) is slidably arranged in each cylinder hole (17), one end of each piston (10) respectively penetrates through the end face of the cylinder block (11) facing the rotating disc (6), and a plurality of oil passage orifices (21) corresponding to the cylinder holes (17) are arranged on the end face of the cylinder block (11) facing the valve plate (12), wherein a plurality of valve holes (13) penetrating the valve plate (12) are arranged in the valve plate (12). The one side of the swash plate (6) towards the cylinder body (11) is provided with a return plate (9), the return plate (9) has a plurality of connecting pins (16), and the one end of each connecting pin (16) towards the swash plate (6) is connected with the swash plate (6) respectively; The return plate (9) is provided with a plurality of through holes, each through hole is provided with a sliding shoe (7) penetratingly installed in the through hole respectively, the one end of each sliding shoe (7) towards the cylinder body (11) is provided with a ball socket respectively, and the one end of each plunger (10) penetrating out of the cylinder body (11) is hinged in the ball socket of the sliding shoe (7) corresponding to each other, and the other end of each sliding shoe (7) is in contact with the corresponding surface of the swash plate (6); The return plate (9) is also in contact with the ball hinge (8) through the central through hole of the return plate (9), the main shaft (1) penetrates the center of the distribution plate (12), the center of the cylinder body (11), the center of the ball hinge (8), the center of the swash plate (6) and the center of the swash plate (5) in sequence, and the main shaft (1) is connected with the cylinder body (11) and the ball hinge (8), so that when the main shaft (1) rotates, the cylinder body (11) and the ball hinge (8) rotate as a whole, and then the return plate (9) rotates and each sliding shoe (7) and plunger (10) rotates, the return plate (9) rotates by the connecting pin (16) to drive the swash plate (6) to rotate, and the swash plate (6) and the swash plate (5) are in clearance fit on the side, that is, not in contact in the radial direction. Each plunger (10) is provided with an oil guide through hole, one end of the oil guide through hole is communicated to the corresponding cylinder hole (17), and the other end of the oil guide through hole is communicated to the ball socket in the corresponding sliding shoe (7), the end surface of each sliding shoe (7) in contact with the swash plate (6) is provided with a static pressure oil chamber (26) respectively, each static pressure oil chamber (26) is communicated with the ball socket in the corresponding sliding shoe (7) respectively, the oil in the cylinder hole (17) in the cylinder body (11) from the distribution plate (12) enters the static pressure oil chamber (26) of the sliding shoe (7) through the oil guide through hole of the plunger (10) and the ball socket of the sliding shoe (7), so that the oil forms a first static pressure support between each sliding shoe (7) and the swash plate (6).

2. A floating swash plate type axial piston pump based on rotation driving of a return spring according to claim 1, characterized in that, The end surface of the cylinder body (11) towards the distribution plate (12) is in clearance fit with the distribution plate (12), the end surface of the cylinder body (11) towards the distribution plate (12) is provided with an oil storage groove (25) corresponding to each oil through hole (21) respectively, the oil storage groove (25) is communicated with the corresponding oil through hole (21) through a damping hole (24) respectively, part of the oil in the oil through hole (21) enters the oil storage groove (25) through the damping hole (24), and then flows into the clearance between the cylinder body (11) and the distribution plate (12) to form a second static pressure support.

3. A floating swash plate type axial piston pump based on rotation driving of a return spring according to claim 1, characterized in that, The swash plate (6) and the swash plate (5) are in clearance fit, the swash plate (6) is provided with an oil guide channel (18) corresponding to each sliding shoe (7) respectively, one end of the oil guide channel (18) is communicated with the static pressure oil chamber (26) of the corresponding sliding shoe (7) respectively, the other end of the oil guide channel (18) is communicated to the clearance between the swash plate (6) and the swash plate (5) respectively, so that the oil in the static pressure oil chamber (26) flows into the oil storage chamber (19) between the swash plate (6) and the swash plate (5) through the oil guide channel (18) to form a third static pressure support.

4. A floating swash plate type axial piston pump based on rotation driving of a return spring according to claim 3, characterized in that, The one side of the swash plate (5) is provided with an oil storage chamber (19) corresponding to each oil guide hole (18), and the other end of the oil guide hole (18) is communicated to the corresponding oil storage chamber (19), so that the oil flows into the gap between the swash plate (5) and the swash plate (5) through the oil storage chamber (19) to form a third static pressure bearing.

5. A floating swash plate type axial piston pump based on rotation driving of a return spring according to claim 4, characterized in that, The one side of the swash plate (5) is further provided with a pressure relief ring groove (20).

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