Main shaft constant-speed driving floating swash plate type axial conical cylinder body plunger pump

Abstract

The invention relates to the technical field of pumps, and discloses a spindle constant-speed driving floating swash plate type axial conical cylinder plunger pump which comprises a pump body and a spindle installed in the pump body, the spindle is connected with an external prime mover, a swash plate, a rotary plate and a cylinder are sequentially arranged on the spindle from the front end of the pump body to the rear end of the pump body, and the swash plate is connected with an inner cavity of the pump body. The rotary disc is matched with the swash plate and is connected with a plurality of plungers in the cylinder body; the hinge structure is arranged on the main shaft, the rotary disc is connected with the main shaft through the hinge structure and is configured to be converted from spherical contact to linear contact through the hinge structure, and axial movement can be generated between the rotary disc and the hinge structure when the main shaft rotates; and the plunger in the cylinder body is obliquely arranged along the axis of the main shaft. According to the application, the limitation on the relative axial movement of the spherical hinge and the rotary disk is eliminated, and the contact stress resistance strength of the hinge structure is improved; and compared with a cylindrical cylinder body structure, the flow distribution pair pv value is reduced, the oil absorption capacity is improved, and the pump can reach a higher rotating speed.

Description

Technical Field

[0001] The invention relates to the technical field of plunger pumps, in particular to a main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump. Background Art

[0002] Hydraulic transmission technology plays a key role in the modern industrial field, especially in the construction machinery industry. Most construction machinery relies on hydraulic transmission technology. As one of the core components of the hydraulic system, the hydraulic pump is a key component for providing power. The swash plate axial piston pump has become a common pump type in the hydraulic system of construction machinery due to its wide application.

[0003] With the pursuit of the dual carbon goals, namely reducing carbon emissions and achieving carbon neutrality, fluid power technology faces new opportunities and challenges. The dual carbon policy is driving the construction machinery industry to transform from traditional internal combustion engines to electric new energy. This transformation has put forward new technical requirements for the swash plate axial piston pump in the hydraulic system, and traditional pump types are facing the challenge of technological innovation. In order to meet the challenges and demands of the new technology, the inventors have previously proposed a series of floating swash plate axial piston pump architectures based on novel principles. However, in the existing floating swash plate axial piston pump architectures, especially for the ball cage type ball joint-ball type transmission scheme, the following deficiencies still exist: 1. First, in the process of the main shaft synchronously driving the rotary plate, since the ball is always at the intersection of the double arc surfaces, that is, the center of the ball is on the angle bisector plane, the rotary plate is in spherical contact with the ball joint and the retaining frame, and the axial movement of the ball joint and the rotary plate is restricted; 2. The inner and outer raceways previously proposed are both single arc raceways, resulting in low installation tolerance, and the contact angle is not easy to control. It changes with the initial clearance and load size, resulting in limited resistance to contact stress; 3. The oil suction capacity of the cylindrical cylinder axial piston pump is weak under high-speed conditions, especially when the displacement pump is large, the diameter of the distribution plate of the cylindrical cylinder axial piston pump is also relatively large, resulting in reduced oil suction capacity and a relatively high PV value of the distribution pair, which limits the increase in the speed of the axial piston pump.

[0004] Therefore, this patent further proposes a main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump to solve the above-mentioned problems existing in the prior art.

[0006] To achieve the above object, the present invention provides the following solution: The present invention provides a main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump, comprising: a pump body and a main shaft installed in the pump body, the main shaft is connected to an external prime mover;

[0007] A swash plate, a rotary plate and a cylinder body are sequentially arranged on the main shaft from the front end of the pump body to the rear end of the pump body, the swash plate is connected to the inner cavity of the pump body, the rotary plate is adapted to the swash plate and connected to a plurality of plungers in the cylinder body;

[0008] An articulated structure is arranged on the main shaft, the rotating disk is connected to the main shaft through the articulated structure, and is configured so that the rotating disk is transformed from spherical contact to linear contact through the articulated structure, and axial movement can be generated between the rotating disk and the articulated structure when the main shaft rotates;

[0009] The plunger in the cylinder body is arranged obliquely along the axis of the main shaft.

[0010] According to a main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump provided by the present invention, the hinge structure comprises:

[0011] A ball joint, arranged on the main shaft;

[0012] A retaining frame, which is sleeved on the ball joint, and the rotary disk is hinged to the ball joint through the retaining frame;

[0013] A plurality of balls are rotatably connected to the retaining frame at equal intervals along the circumferential direction, and the outer side wall of the ball joint and the inner side wall of the rotating disk are in contact with the balls respectively.

[0014] According to a spindle constant speed driven floating slant plate type axial conical cylinder plunger pump provided by the present invention, a plurality of through holes are opened on the retaining frame at equal intervals along the circumferential direction, a plurality of inner raceways are opened on the outer wall of the ball joint at equal intervals along the circumferential direction, a plurality of outer raceways are opened on the inner wall of the rotating plate at equal intervals along the circumferential direction, the plurality of inner raceways and the plurality of outer raceways correspond one to one with the plurality of through holes respectively, and the plurality of balls are respectively installed in the plurality of through holes and roll in the inner raceways and the outer raceways.

[0015] According to a main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump provided by the present invention, the through hole is a waist-shaped through hole, and the cross section of the inner raceway and the outer raceway is one of a single arc, an ellipse or a double arc.

[0016] According to a spindle constant-speed driven floating swash plate type axial conical cylinder plunger pump provided by the present invention, the center of the outer spherical surface of the retaining frame is B, the center of the inner spherical surface of the retaining frame is C, the center of the circle of the plane formed by the swing center of the swash plate, the center of the retaining frame and the center of the plunger ball head coincides at O, and OB=OC.

[0017] According to the present invention, a main shaft constant speed driven floating slant plate type axial tapered cylinder plunger pump is provided, wherein a plurality of cylinder holes are opened in the cylinder body at equal intervals along the circumferential direction, the cylinder holes are inclined to the axis of the main shaft and are connected to the oil through port, a plurality of ball sockets are opened in the circumferential direction at equal intervals on one side of the rotary plate close to the cylinder body, the plunger is slidably connected to the ball head in the cylinder hole, the ball head extends out of the cylinder hole and is hinged to the ball socket.

[0018] According to the present invention, a main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump is provided, wherein the cylinder is a tapered structure.

[0019] According to a main shaft constant speed driven floating slant plate type axial conical cylinder plunger pump provided by the present invention, a channel is opened in the middle of the cylinder body, a center spring is arranged in the channel, the center spring is sleeved on the main shaft, and a plurality of push rods are axially arranged on the cylinder body, one end of the push rod passes through the cylinder body and contacts the ball joint, and the other end of the push rod extends into the channel and is fixedly connected to the center spring.

[0020] According to a main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump provided by the present invention, a front end cover is fixedly connected to the front end of the pump body, a base is fixedly connected to the pump body, a bearing is fixedly connected between the front end cover and the base, the main shaft is rotatably connected to the pump body through the bearing, the swash plate is mounted on the base, a variable lever is installed in the pump body, and the swash plate is hinged to the variable lever.

[0021] According to a main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump provided by the present invention, a pressure relief ring groove is provided on a side of the swash plate close to the rotating plate, the rotating plate is located in the pressure relief ring groove, a plurality of oil storage chambers are provided at equal intervals along the circumferential direction on a side of the rotating plate close to the swash plate, an oil guide channel is provided in the oil storage chamber, and the oil guide channel is communicated with the ball socket;

[0022] The plunger is provided with a channel, the cylinder hole is connected with the ball socket through the channel, and is configured so that when the oil in the cylinder hole enters the oil storage chamber through the channel and the oil guide channel, the oil forms a static pressure support in the pressure relief ring groove.

[0023] Compared with the prior art, the present invention has the following advantages and technical effects:

[0024] The present invention provides a main shaft constant speed driven floating inclined plate type axial tapered cylinder plunger pump, the main shaft is driven to rotate by an external prime mover, the turntable is connected to the main shaft by a hinge structure, when the main shaft rotates, the turntable is driven to rotate and can have the freedom of axial movement, the axial movement restriction of the turntable at the hinge point is removed, and at the same time, the anti-contact stress strength is improved by the set hinge structure, and the inclined plunger is arranged obliquely relative to the main shaft so that the tail end has a tapered structure, the centrifugal force of the plunger will generate a centrifugal force component along the axial direction of the plunger, under the action of this centrifugal force component, it helps the return movement of the plunger when it is in the oil suction area, further increasing the oil suction capacity of the pump, for axial piston pumps of the same displacement, the tapered cylinder structure is compared with the cylindrical cylinder structure, because the PV value (i.e., the product of stress and linear velocity) of the distribution pair is lower and the oil suction capacity is stronger, so through the cylinder body with a tapered structure, the rotation speed of the plunger pump can reach a higher rotation speed than the axial piston pump with a cylindrical cylinder structure. The present application reduces the restriction on the relative axial movement of the ball joint and the rotary plate, improves the overall contact stress resistance of the pump, and can achieve a higher rotation speed than an axial piston pump with a cylindrical cylinder structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor:

[0026] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 It is a quarter cross-sectional view of the overall structure of the present invention;

[0028] Figure 3 A quarter cross-sectional view of the hinge structure of the present invention;

[0029] Figure 4 It is a schematic diagram of the installation position of the hinged structure of the present invention;

[0030] Figure 5 It is a schematic diagram of the cylinder structure of the present invention;

[0031] Figure 6 This is a schematic diagram of the structure of the rotary disk of the present invention;

[0032] Figure 7 This is a comparison diagram of the turntable of the present invention before and after swinging;

[0033] Figure 8 This is a schematic diagram of the ball joint structure of the present invention;

[0034] Fig. 9 It is a schematic diagram of the structure of the cage of the present invention;

[0035] Fig.10 This is a schematic diagram of the structure of the distribution plate of the present invention;

[0036] Fig.11 It is a schematic diagram of the axis of the rotating structure of the present invention;

[0037] Fig.12 Schematic diagrams of different cross sections of the track of the present invention;

[0038] Fig.13 This is a schematic diagram of the pressure relief ring groove structure of the present invention;

[0039] Fig.14 This is a schematic diagram of the structure of the oil storage chamber of the present invention;

[0040] Among them, 1. main shaft; 2. variable lever; 3. front end cover; 4. bearing; 5. base; 6. swash plate; 7. slewing plate; 8. retaining frame; 9. ball joint; 10. ball; 11. cylinder block; 12. plunger; 13. distribution plate; 14. turbine; 15. push rod; 16. center spring; 17. cylinder hole; 18. oil port; 19. ball socket; 20. outer raceway; 21. inner raceway; 22. through hole; 23. distribution hole; 24. pressure relief ring groove; 25. oil storage chamber; 26. oil guide channel. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] Reference Figure 1-Figure 14 The present invention provides a main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump, comprising: a pump body and a main shaft 1 installed in the pump body, the main shaft 1 is connected to an external prime mover,

[0044] A swash plate 6, a rotary plate 7 and a cylinder body 11 are arranged in sequence from the front end to the rear end of the pump body on the main shaft 1. The swash plate 6 is connected to the inner cavity of the pump body. The rotary plate 7 is adapted to the swash plate 6 and connected to a plurality of plungers 12 in the cylinder body 11.

[0045] The hinge structure is arranged on the main shaft 1, and the rotating disk 7 is connected to the main shaft 1 through the hinge structure, and is configured so that the rotating disk 7 is transformed from spherical contact to linear contact through the hinge structure, and when the main shaft 1 rotates, the rotating disk 7 and the hinge structure can be allowed to have a degree of freedom of relative axial movement;

[0046] The plunger 12 in the cylinder body 11 is arranged obliquely along the axis of the main shaft 1 .

[0047] In one embodiment of the present invention, specifically, the main shaft 1 is driven to rotate by an external prime mover, and the turntable 7 is connected to the main shaft 1 through a hinge structure. When the main shaft 1 rotates, the turntable 7 is driven to rotate and can have the freedom to move axially relative to the ball joint 9, thereby eliminating the restriction of the hinge point on the axial movement freedom of the turntable relative to the ball joint in the prior art, and by setting an inclined plunger 12, the tail end has a conical structure.

[0048] Specifically, under the same displacement, the diameter of the distribution plate 13 of the axial piston pump with a conical cylinder body 11 structure can be made smaller than the diameter of the distribution plate of the axial piston pump with a cylindrical cylinder body structure, which is beneficial to improving the oil suction capacity of the pump and reducing the PV value of the distribution pair. At the same time, since the plunger 12 in the conical cylinder body 11 structure is arranged obliquely relative to the main shaft 1, the centrifugal force of the plunger 12 will generate a centrifugal force component along the axial direction of the plunger. Under the action of this centrifugal force component, it helps the return movement of the plunger 12 when it is in the oil suction area, further increasing the oil suction capacity of the pump. For axial piston pumps of the same displacement, the conical cylinder body 11 structure has a lower PV value of the distribution pair and a stronger oil suction capacity than the cylindrical cylinder body structure. Therefore, the rotation speed of the axial piston pump with a conical cylinder body structure can reach a higher speed than that of the axial piston pump with a cylindrical cylinder body structure.

[0049] As an optional embodiment, the hinge structure includes:

[0050] A ball joint 9 is arranged on the main shaft 1;

[0051] The retaining frame 8 is sleeved on the ball joint 9, and the rotary plate 7 is hinged to the ball joint 9 through the retaining frame 8;

[0052] A plurality of balls 10 are rotatably connected to the retaining frame 8 at equal intervals along the circumferential direction, and the outer wall of the ball joint 9 and the inner wall of the rotating disk 7 are in contact with the balls 10 respectively.

[0053] In one embodiment of the present invention, referring to Figure 3 The balls 10 are arranged to realize the rotation between the rotary disk 7 and the ball joint 9 and enable them to have the function of relative axial movement.

[0054] As an optional embodiment, a plurality of through holes 22 are opened on the retaining frame 8 at equal intervals along the circumferential direction, a plurality of inner raceways 21 are opened on the outer wall of the ball joint 9 at equal intervals along the circumferential direction, and a plurality of outer raceways 20 are opened on the inner wall of the turntable at equal intervals along the circumferential direction. The plurality of inner raceways 21 and the plurality of outer raceways 20 correspond one-to-one to the plurality of through holes 22 respectively, and the plurality of balls 10 are respectively installed in the plurality of through holes 22 and roll in the inner raceways 21 and the outer raceways 20.

[0055] In one embodiment of the present invention, referring to Figure 6 , Figure 7 , Figure 8 , Fig. 9 When the central axes of the ball joint 9 and the turntable 7 are at any interaxial angle, the centers of all the balls 10 are located on the bisector of the angle between the central axes of the ball joint 9 and the turntable 7. Therefore, the ball joint 9 can synchronously drive the turntable 7 to rotate at a constant speed, and during the rotation, relative axial movement is allowed between the turntable 7 and the ball joint 9 to ensure the floating characteristics of the turntable 7. The cross-section of the raceway is newly increased by an elliptical raceway and a double arc raceway from a single arc raceway. In the elliptical raceway, the contact point between the ball 10 and the raceway and the line connecting the center of the ball 10 pass through the radial direction of the center of the ball to form an angle of 45°, which can achieve higher transmission efficiency and load-bearing capacity; in the double arc raceway, the contact angle between the ball 10 and the raceway can remain unchanged, so the transmission efficiency, load-bearing capacity and axial stiffness are relatively stable.

[0056] Specifically, the number of the inner raceway 21 on the ball joint 9, the outer raceway 20 on the rotary plate 7, the balls 10 and the through holes 22 of the retaining frame 8 is preferably 6, and may be other numbers depending on the size of the transmitted force and torque.

[0057] As an optional implementation, the through hole 22 is a waist-shaped through hole, and the cross-sections of the inner raceway 21 and the outer raceway 20 are single arc, elliptical or double arc shapes.

[0058] In one embodiment of the present invention, referring to Fig.12 The cross-section of the inner raceway 21 and the outer raceway 20 is one of a single arc, an ellipse or a double arc.

[0059] Specifically, the inner side of the turntable 7 is a cylindrical surface rather than a spherical surface, thereby forming a linear contact with the outer side of the spherical surface of the retainer 8. The retainer 8 is divided into inner and outer spherical surfaces, wherein the inner spherical surface cooperates with the ball joint 9, and the outer spherical surface cooperates with the cylindrical surface of the turntable 7. Relative axial movement can be generated between the turntable 7 and the ball joint 9. The raceways on the turntable 7 and the ball joint 9 are straight grooves. The raceways formed after the two are assembled are equipped with balls 10. The balls 10 are also installed in the holes of the retainer 8, and the retainer 8 cooperates with the inner cylindrical surface of the turntable 7 to achieve axial movement.

[0060] As an optional embodiment, the center of the outer sphere of the retainer 8 is B, the center of the inner sphere of the retainer 8 is C, the center of the plane formed by the swing center of the swash plate 6, the center of the retainer 8 and the center of the ball head of the plunger 12 coincides at O, and OB=OC.

[0061] In one embodiment of the present invention, referring to Figure 7 , Fig.11 When there is an angle between the central axis of the cylinder body and the axis of the main shaft 1, the linear groove raceway of the ball joint 9 of the main shaft 1 and the linear raceway of the turntable 7 intersect at the angle bisector AA and pass through the point O. At this time, the center C of the inner spherical surface of the retaining frame 8 matches the outer surface of the ball joint 9, and the center B of the outer spherical surface of the retaining frame 8 always coincides with the central axis of the turntable 7, that is, the retaining frame 8 is in line contact with the cylindrical surface of the turntable 7, and OB=OC.

[0062] As an optional embodiment, a plurality of cylinder holes 17 are opened in the cylinder body 11 at equal intervals along the circumferential direction. The cylinder hole 17 is inclined to the axis of the main shaft 1 and is connected to the oil port 18. A plurality of ball sockets 19 are opened at equal intervals along the circumferential direction on the side of the turntable 7 close to the cylinder body 11. The plunger 12 is slidably connected in the cylinder hole 17, and the ball head extends out of the cylinder hole 17 and is hinged to the ball socket 19.

[0063] In one embodiment of the present invention, referring to Figure 4 The connection between the rotary disk 7 and the plunger 12 is achieved by hingedly connecting the plunger 12 and the ball socket 19. Specifically, the plunger 12 is a thin rod plunger.

[0064] As an optional implementation, the cylinder body 11 is a conical structure.

[0065] In one embodiment of the present invention, referring to Figure 5 The cylinder body 11 is a conical structure, which, together with the thin rod structure plunger 12, is conducive to reducing the distribution diameter of the distribution plate 13, thereby reducing the linear velocity of the cylinder body distribution surface and reducing the weight of the pump. Since the volume of the sealed working cavity formed in the cylinder hole 17 of the cylinder body 11 behind the plunger 12 is reduced, the oil hydraulic pressure in the cylinder hole 17 of the cylinder body 11 increases to form high-pressure oil.

[0066] As an optional embodiment, a channel is opened in the middle of the cylinder body 11, and a center spring 16 is arranged in the channel. The center spring 16 is sleeved on the main shaft 1, and a plurality of push rods 15 are axially arranged on the cylinder body 11. One end of the push rod 15 passes through the cylinder body 11 and contacts with the ball joint 9, and the other end of the push rod 15 extends into the channel and is fixedly connected with the center spring 16.

[0067] In one embodiment of the present invention, referring to Figure 4 A center spring 16 is provided in the hole, and one end of the center spring 16 acts on the ball joint 9 through the push rod 15, so that the ball joint 9 is pressed against the rotating plate 7, and the rotating plate 7 is pressed against the inclined plate 6.

[0068] As an optional embodiment, a front end cover 3 is fixedly connected to the front end of the pump body, a base 5 is fixedly connected inside the pump body, a bearing 4 is fixedly connected between the front end cover 3 and the base 5, the main shaft 1 is rotatably connected to the pump body through the bearing 4, a swash plate 6 is installed on the base 5, a variable lever 2 is installed in the pump body, and the swash plate 6 is hinged to the variable lever 2.

[0069] Specifically, the central axis of the swash plate 6 forms an acute angle with respect to the front-rear direction straight line.

[0070] In one embodiment of the present invention, referring to Figure 1 A variable lever 2 is also installed in the pump body. The variable lever 2 is connected to the edge of the swash plate 6 by a ball joint. The swash plate 6 is pushed to shift the variable lever 2, thereby adjusting the inclination angle of the swash plate 6.

[0071] As an optional embodiment, a pressure relief ring groove 24 is provided on one side of the swash plate 6 close to the rotating plate 7, the rotating plate 7 is located in the pressure relief ring groove 24, a plurality of oil storage chambers 25 are provided at equal intervals along the circumferential direction on one side of the rotating plate 7 close to the swash plate 6, an oil guide channel 26 is provided in the oil storage chamber 25, and the oil guide channel 26 is connected to the ball socket 19;

[0072] A channel is provided on the plunger 12 , and the cylinder hole 17 is connected to the ball socket 19 through the channel. The plunger 12 is configured such that when the oil in the cylinder hole 17 enters the oil storage chamber 25 through the channel and the oil guide hole 26 , the oil forms a static pressure support in the pressure relief ring groove 24 .

[0073] As an optional implementation, a distribution plate 13 is installed in the pump body. The distribution plate 13 is arranged in contact with the cylinder body 11 , and a distribution hole 23 is arranged on the distribution plate 13 .

[0074] In one embodiment of the present invention, referring to Fig.10 The distribution hole 23 is a waist-shaped hole, and the high-pressure oil is discharged through the oil discharge waist-shaped hole of the distribution plate 13.

[0075] Specifically, the other end of the center spring 16 acts on the cylinder body 11 , so that the cylinder body 11 is pressed toward the distribution plate 13 .

[0076] Working principle of the present invention:

[0077] The main shaft 1 is rotated by the prime mover, and the rotating main shaft 1 drives the cylinder body 11 and the ball joint 9 to rotate synchronously through the spline connection. When the swash plate 6 is 0 degrees, the ball 10 clamped in the through hole 22 of the retaining frame 8 can roll freely on the center line of the inner raceway 21 on the ball joint 9 and the outer raceway 20 on the turntable 7. The retaining frame 8 ensures that the ball 10 is always in the same angle bisector. With the change of the inclination angle of the swash plate 6, that is, with the change of the angle of the central axis between the turntable 7 and the ball joint 9, when the angle of the central axis between the turntable 7 and the ball joint 9 is constant, the ball 10 clamped in the through hole 22 of the retaining frame 8 is positioned by the cross action of the inner raceway 21 of the ball joint 9 and the outer raceway 20 on the turntable 7, and the ball 10 transmits force and torque between the ball joint 9 and the turntable 7. The cage 8 has an inner spherical surface and an outer spherical surface. The inner spherical surface of the cage 8 is in contact with the spherical outer surface of the ball joint 9, and the outer spherical surface of the cage 8 is in contact with the cylindrical surface of the middle through hole of the rotating disk 7, that is, the rotating disk 7 is supported on the ball joint 9 by contact. When the central axes of the ball joint 9 and the rotating disk 7 are at any axis angle, the centers of all the balls 10 are located on the bisector of the angle between the central axes of the ball joint 9 and the rotating disk 7, so the ball joint 9 can synchronously drive the rotating disk 7 to rotate at a constant speed, and during the rotation process, relative axial movement is allowed between the rotating disk 7 and the ball joint 9 to ensure the floating characteristics of the rotating disk 7.

[0078] During the rotation cycle of the cylinder body 11, the plunger 12 gradually extends out of the cylinder body 11 under the action of the rotary disk 7 and the corresponding cylinder hole 17 in the cylinder body 11. As the plunger 12 gradually extends, the volume of the sealed working chamber corresponding to the cylinder hole 17 of the cylinder body 11 continues to increase, generating a partial vacuum. When the cylinder hole 17 that forms the partial vacuum rotates to the position where the oil port 18 is aligned with the distribution hole 23 of the distribution plate 13, the low-pressure oil from the hydraulic system is sucked into the cylinder hole 17 that forms the partial vacuum through the distribution hole 23 of the distribution plate 13.

[0079] The cylinder body 11 continues to rotate, and the plunger 12 is gradually pushed into the cylinder hole 17, thereby pushing the oil that originally entered the corresponding cylinder hole 17 of the cylinder body 11 out of the cylinder hole 17, and because the volume of the sealed working cavity formed in the corresponding cylinder hole 17 of the cylinder body 11 behind the plunger 12 is reduced, the hydraulic pressure of the oil in the cylinder hole 17 of the cylinder body 11 increases to form high-pressure oil. When the cylinder body 11 rotates until the oil port 18 is aligned with the oil discharge distribution hole of the distribution plate 13, the high-pressure oil is discharged through the oil discharge distribution hole of the distribution plate 13.

[0080] The present invention provides a main shaft constant speed driven floating inclined plate type axial tapered cylinder plunger pump, which realizes the synchronous rotation between the turntable 7 and the ball joint 9 and enables the pump to have the function of relative axial movement through the arranged balls 10. When the central axes of the ball joint 9 and the turntable 7 are at any axis angle, the centers of all the balls 10 are located on the bisector of the angle between the central axes of the ball joint 9 and the turntable 7. Therefore, the ball joint 9 can synchronously drive the turntable 7 to rotate at a constant speed, and during the rotation process, relative axial movement is allowed between the turntable 7 and the ball joint 9 to ensure the floating characteristics of the turntable 7. The cross section of the raceway is increased by an elliptical raceway and a double arc raceway from a single arc raceway. In the elliptical raceway, the contact point between the ball 10 and the raceway and the line connecting the center of the ball 10 pass through the radial direction of the center of the ball to form an angle of 45°, which can achieve higher transmission efficiency and load-bearing capacity; in the double arc raceway, the contact angle between the ball 10 and the raceway can It remains unchanged, so the transmission efficiency, load-bearing capacity and axial stiffness are relatively stable. Since the plunger 12 in the tapered cylinder body 11 structure is tilted relative to the main shaft 1, the centrifugal force of the plunger 12 will generate a centrifugal force component along the axial direction of the plunger. Under the action of this centrifugal force component, it is helpful for the return movement of the plunger 12 when it is in the oil suction area, further increasing the oil suction capacity of the pump. In addition, under the same displacement, the diameter of the distribution plate 13 of the axial piston pump with the tapered cylinder body 11 structure can be made smaller than the diameter of the distribution plate of the axial piston pump with the cylindrical cylinder body structure, which is beneficial to improving the oil suction capacity of the pump and reducing the PV value of the distribution pair. For axial piston pumps of the same displacement, the tapered cylinder body 11 structure has a lower PV value of the distribution pair and a stronger oil suction capacity than the cylindrical cylinder body structure. Therefore, the speed of the axial piston pump with the tapered cylinder body structure can reach a higher speed than the axial piston pump with the cylindrical cylinder body structure.

[0081] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0082] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump, comprising: A pump body and a main shaft (1) installed in the pump body, wherein the main shaft (1) is connected to an external prime mover, characterized in that: A swash plate (6), a rotary plate (7) and a cylinder body (11) are sequentially arranged on the main shaft (1) from the front end of the pump body to the rear end of the pump body, the swash plate (6) is connected to the inner cavity of the pump body, the rotary plate (7) is adapted to the swash plate (6) and is connected to a plurality of plungers (12) in the cylinder body (11); an articulated structure, arranged on the main shaft (1), the rotating disk (7) being connected to the main shaft (1) via the articulated structure, and being configured so that the spherical contact of the rotating disk (7) is transformed into linear contact via the articulated structure, and when the main shaft (1) rotates, an axial movement can be generated between the rotating disk (7) and the articulated structure; The plunger (12) in the cylinder body (11) is arranged obliquely along the axis of the main shaft (1).

2. A main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump according to claim 1, characterized in that: The hinge structure comprises: A ball joint (9) is arranged on the main shaft (1); A retaining frame (8) is sleeved on the ball joint (9), and the rotary disk (7) is hinged to the ball joint (9) through the retaining frame (8); A plurality of balls (10) are rotatably connected to the retaining frame (8) at equal intervals along the circumferential direction, and the outer wall of the ball joint (9) and the inner wall of the rotating disk (7) are in contact with the balls (10) respectively.

3. The main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump according to claim 2, characterized in that: The retaining frame (8) is provided with a plurality of through holes (22) at equal intervals in the circumferential direction, the outer wall of the ball joint (9) is provided with a plurality of inner raceways (21) at equal intervals in the circumferential direction, and the inner wall of the turntable (7) is provided with a plurality of outer raceways (20) at equal intervals in the circumferential direction. The plurality of inner raceways (21) and the plurality of outer raceways (20) correspond to the plurality of through holes (22) respectively, and the plurality of balls (10) are respectively installed in the plurality of through holes (22) and roll in the inner raceways (21) and the outer raceways (20).

4. The main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump according to claim 3, characterized in that: The through hole (22) is a waist-shaped through hole, and the cross-sections of the inner raceway (21) and the outer raceway (20) are one of a single arc, an ellipse or a double arc.

5. The main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump according to claim 3, characterized in that: The center of the outer sphere of the retaining frame (8) is B, the center of the inner sphere of the retaining frame (8) is C, the center of the circle of the plane formed by the swing center of the swash plate (6), the center of the retaining frame (8) and the center of the ball head of the plunger (12) coincides at O, and OB=OC.

6. The main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump according to claim 2, characterized in that: A plurality of cylinder holes (17) are formed in the cylinder body (11) at equal intervals along the circumferential direction. The cylinder holes (17) are arranged obliquely with respect to the axis of the main shaft (1) and are connected to an oil port (18). A plurality of ball sockets (19) are formed at equal intervals along the circumferential direction on one side of the rotary disk (7) close to the cylinder body (11). The plunger (12) is slidably connected to the cylinder hole (17), and the ball head of the plunger (12) extends out of the cylinder hole (17) and is hingedly connected to the ball socket (19).

7. The main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump according to claim 1, characterized in that: The cylinder body (11) is a conical structure.

8. The main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump according to claim 2, characterized in that: A hole is opened in the middle of the cylinder body (11), a center spring (16) is arranged in the hole, and the center spring (16) is sleeved on the main shaft (1). A plurality of push rods (15) are axially arranged on the cylinder body (11), one end of the push rod (15) passes through the cylinder body (11) and contacts the ball joint (9), and the other end of the push rod (15) extends into the hole and is fixedly connected to the center spring (16).

9. The main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump according to claim 1, characterized in that: A front end cover (3) is fixedly connected to the front end of the pump body, a base (5) is fixedly connected to the pump body, a bearing (4) is fixedly connected between the front end cover (3) and the base (5), the main shaft (1) is rotatably connected to the pump body via the bearing (4), the swash plate (6) is mounted on the base (5), a variable lever (2) is mounted in the pump body, and the swash plate (6) is hinged to the variable lever (2).

10. The main shaft constant speed driven floating swash plate type axial tapered cylinder plunger pump according to claim 6, characterized in that: A pressure relief annular groove (24) is provided on one side of the swash plate (6) close to the rotating plate (7), the rotating plate (7) is located in the pressure relief annular groove (24), a plurality of oil storage chambers (25) are provided at equal intervals along the circumferential direction on one side of the rotating plate (7) close to the swash plate (6), an oil guide channel (26) is provided in the oil storage chamber (25), and the oil guide channel (26) is communicated with the ball socket (19); The plunger (12) is provided with a channel, the cylinder hole (17) is connected to the ball socket (19) through the channel, and is configured such that when the oil in the cylinder hole (17) enters the oil storage chamber (25) through the channel and the oil guide channel (26), the oil forms a static pressure support in the pressure relief ring groove (24).

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