A liquid variable displacement fluid delivery pump

Abstract

This invention relates to the field of fluid pump technology, specifically to a liquid variable displacement fluid transfer pump, which includes a pump body, a plunger, a slipper, and a control assembly. Initially, the damping orifice is set to a larger size, allowing the liquid inside the sliding chamber to quickly enter the pressure balance chamber, thereby achieving a rapid response and reducing the probability of wear on the contact surface between the slipper and the eccentric wheel. When wear occurs on the contact surface between the slipper and the eccentric wheel, causing leakage in the pressure balance chamber, the pressure difference between the pressure balance chamber and the sliding chamber increases. The control assembly automatically senses this pressure difference change and reduces the size of the damping orifice, making it more difficult for the liquid to pass through the damping orifice. This reduces the static pressure support effect inside the pressure balance chamber and increases the positive pressure of the slipper on the eccentric wheel, thereby preventing further leakage of liquid inside the pressure balance chamber.

Description

Technical Field

[0001] This invention relates to the field of fluid pump technology, and more specifically to a liquid variable displacement fluid transfer pump. Background Technology

[0002] Variable displacement fluid transfer pumps are core power components of hydraulic transmission and control systems. Among them, radial piston pumps, with their significant advantages such as high working pressure, excellent volumetric efficiency, and wide flow adjustment range, have become indispensable key components in high-end equipment fields such as engineering machinery, aerospace, and marine engineering. Radial piston pumps complete the liquid suction and discharge process through the reciprocating linear motion of the piston within the cylinder.

[0003] During the actual operation of a radial piston pump, the piston is driven through a slipper and an eccentric wheel. At this time, the bottom of the slipper and the surface of the eccentric wheel are subjected to extremely high contact normal pressure, and there is a large relative speed between them. This makes the friction contact surface prone to severe wear. This problem not only significantly shortens the pump's service life but also leads to a significant reduction in mechanical efficiency.

[0004] To improve the aforementioned friction and wear problems, the industry generally opens a pressure balance chamber at the end of the slipper that contacts the eccentric wheel, and opens a damping hole inside the slipper and a pressure guiding hole inside the plunger. The damping hole and the pressure guiding hole together connect the sliding chamber and the pressure balance chamber. The high-pressure liquid inside the sliding chamber achieves hydrostatic support, offsetting part of the liquid pressure in the sliding chamber, further reducing the normal pressure between the slipper and the surface of the eccentric wheel, and reducing friction loss.

[0005] However, when the surface in contact with the eccentric wheel wears, and the pressure in the pressure balance chamber is greater than the external ambient pressure, the liquid in the pressure balance chamber will leak. Subsequently, the pressure in the pressure balance chamber will drop rapidly, and the damping orifice will prevent the liquid from entering the pressure balance chamber from the sliding chamber. If the damping orifice is too small, the liquid inside the sliding chamber cannot replenish the pressure balance chamber in time, which can easily further aggravate the wear between the bottom of the slipper and the surface of the eccentric wheel. If the damping orifice is too large, the liquid inside the sliding chamber will quickly enter the pressure balance chamber. Once the pressure balance chamber leaks, the damping orifice cannot prevent the liquid from entering the pressure balance chamber in time, which can easily lead to an increase in the amount of liquid leaking in the pressure balance chamber. In addition, after the pressure difference between the pressure in the pressure balance chamber and the pressure inside the sliding chamber increases, the slipper will press against the surface of the eccentric wheel again under the action of the pressure difference. This cycle of "pressure increase-disengagement-leakage-pressure decrease-pressurization" will cause the slipper to vibrate violently, resulting in a significant decrease in the working stability of the pump, and even causing the entire machine to fail. Summary of the Invention

[0006] This invention provides a liquid variable displacement fluid transfer pump to solve the problem of unstable operation of existing transfer pumps.

[0007] The present invention provides a liquid variable displacement fluid transfer pump using the following technical solution: A liquid displacement pump includes a pump body, a plunger, a slipper, and a control assembly.

[0008] The pump body has an internal drive chamber containing an eccentrically rotating eccentric wheel. A pump tube is mounted radially on the pump body, and a sliding chamber is located inside the pump tube. A plunger is slidably disposed within the sliding chamber. A pressure-guiding hole is located inside the plunger and communicates with the sliding chamber. A ball joint groove is located at the end of the plunger near the eccentric wheel. A first elastic element is located between the end of the plunger away from the eccentric wheel and the end of the pump tube. A ball head is located at one end of the slipper, positioned within the ball joint groove. The other end of the slipper abuts against the eccentric wheel, and a pressure balance chamber is located at the end of the slipper abutting against the eccentric wheel. A damping orifice is located inside the slipper, connecting the pressure balance chamber to the pressure-guiding hole. The control component is configured to adjust the size of the damping orifice based on the pressure difference between the pressure balance chamber and the sliding chamber.

[0009] Furthermore, the control component includes a damping tube, a sensing drive, and a damping plug. The sliding shoe has a control cavity inside, and the damping tube is slidably disposed within the control cavity. The end of the control cavity away from the eccentric wheel has a first communication port connecting to the pressure guide hole, and the end of the control cavity near the eccentric wheel has a second communication port connecting to the pressure balance chamber. The damping plug is fixedly disposed at the end of the control cavity near the eccentric wheel. The damping plug can enter the interior of the damping tube, and when the damping tube slides relative to the control cavity, the size of the opening at the end of the damping tube blocked by the damping plug can change. The sensing drive is used to sense the pressure difference between the interior of the damping tube and the interior of the pressure balance chamber, and the sensing drive can also drive the damping tube to slide relative to the control cavity when a pressure difference exists.

[0010] Furthermore, the sensing drive includes a drive ring, which is coaxially and fixedly sleeved on the outer wall of the damping tube, and the outer wall of the drive ring is sealed to the inner wall of the control cavity; a sensing hole is provided on the side wall of the damping tube, and the sensing hole is located on the side of the drive ring away from the damping plug.

[0011] Furthermore, the control component also includes a second elastic element, which is disposed between the end of the control cavity and the end of the damping tube.

[0012] Furthermore, the control component also includes a compensation unit configured to adjust the contact pressure between the slipper and the eccentric wheel when the damping tube slides relative to the control cavity.

[0013] Furthermore, the damping tube is divided into a first section and a second section, which are coaxially connected. The first section is located close to the eccentric wheel, and the drive ring is fixedly mounted on the first section. When the first section moves closer to the eccentric wheel, the second section moves away from the eccentric wheel. The compensation unit includes a compensation rod, which is mounted on the second section. The compensation rod passes through the end of the control cavity away from the eccentric wheel, and the compensation rod can compress the ball joint groove of the plunger.

[0014] Furthermore, the compensation unit also includes a transmission component, which is used to convert the first segment of motion approaching the eccentric wheel into the second segment of motion moving away from the eccentric wheel.

[0015] Furthermore, the transmission component includes a one-way gear, a connecting gear ring, a connecting ring, and a guide; the connecting ring is coaxially slidably connected to the outer surface of the first segment, and the connecting gear ring is threadedly connected to the inner sidewall of the adjustment cavity; the diameter of the second segment is larger than the diameter of the first segment, the connecting gear ring abuts against the end face of the second segment, the connecting gear ring is coaxially disposed outside the connecting ring, and the one-way gear is disposed between the connecting gear ring and the connecting ring; the guide is used to guide the first segment to rotate when the first segment approaches the eccentric wheel.

[0016] Furthermore, the guide includes a guide rod and a guide arc groove. The guide arc groove is disposed on the outer wall of the drive ring, the guide rod is fixedly disposed on the side wall of the control cavity, and the guide rod is slidably disposed in the guide arc groove.

[0017] Furthermore, the axis of the compensating push rod is parallel to and spaced apart from the axis of the damping tube, and in the direction of rotation of the eccentric wheel, the compensating push rod is located upstream of the movement trajectory of the damping tube axis.

[0018] The beneficial effects of this invention are as follows: This invention provides a liquid variable displacement fluid transfer pump, comprising a pump body, a plunger, a sliding shoe, and a regulating assembly. During pump operation, an eccentric wheel rotates eccentrically within the drive chamber. The eccentric wheel, through the sliding shoe, pushes the plunger to reciprocate linearly along the sliding chamber within the pump tube, causing the sliding chamber to alternately generate negative and high pressures, completing the liquid suction and discharge process. The high-pressure liquid in the sliding chamber continuously flows into the pressure balance chamber at the bottom of the sliding shoe through the pressure guiding hole inside the plunger and the damping hole inside the sliding shoe, achieving static pressure support to offset most of the contact positive pressure. Initially, the damping hole is set at a relatively large position. In the sliding chamber, the liquid inside can quickly enter the pressure balance chamber, thus achieving a rapid response and reducing the probability of wear on the contact surface between the slipper and the eccentric wheel. When wear occurs on the contact surface between the slipper and the eccentric wheel, causing leakage in the pressure balance chamber, the pressure difference between the pressure balance chamber and the sliding chamber increases. The control component automatically senses this pressure difference change and reduces the size of the damping orifice. This increases the difficulty for the liquid to pass through the damping orifice, reduces the static pressure support effect inside the pressure balance chamber, and increases the positive pressure of the slipper on the eccentric wheel, thereby preventing further leakage of liquid inside the pressure balance chamber.

[0019] Furthermore, when wear of the slipper leads to an increase in the gap between it and the eccentric wheel, the sliding displacement of the damping tube under the action of pressure difference will simultaneously trigger the compensation unit to operate, increasing the contact normal pressure between the slipper and the eccentric wheel. While maintaining pressure balance, it compensates for the gap caused by wear, ensuring that the slipper and the eccentric wheel always maintain the optimal hydrostatic support gap, thereby reducing the probability of vibration during the operation of the delivery pump. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of a variable displacement fluid transfer pump provided in an embodiment of the present invention; Figure 2 A side view of a liquid displacement fluid transfer pump provided in an embodiment of the present invention; Figure 3 for Figure 2 A cross-sectional view along the AA direction; Figure 4 for Figure 3 A magnified view of a section at point B in the middle; Figure 5 This is a schematic diagram of the structure of a sliding shoe in a liquid variable displacement fluid transfer pump provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the cross-sectional opening of the outer shell of a sliding shoe in a liquid displacement fluid transfer pump provided in an embodiment of the present invention.

[0022] In the diagram: 110, pump body; 111, drive chamber; 120, eccentric wheel; 130, pump pipe; 131, sliding chamber; 140, inlet pipe; 150, outlet pipe; 210, plunger; 211, pressure guide hole; 212, first elastic element; 220, slipper; 221, pressure balance chamber; 222, regulating chamber; 223, first connecting port; 224, second connecting port; 310, damping tube; 311, first section; 3111, sensing hole; 312, second section; 320, damping plug; 330, drive ring; 340, second elastic element; 350, compensating push rod; 360, push spring; 410, one-way gear; 420, connecting gear ring; 430, connecting ring; 440, guide rod; 450, guide arc groove. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] The component designations used in this document, such as "first" and "second," are merely for distinguishing the described objects and do not have any sequential or technical meaning. The terms "connection" and "linkage" used in this invention, unless otherwise specified, include both direct and indirect connections (linkages). It should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0025] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0026] like Figures 1 to 6 As shown in the figure, an embodiment of the present invention provides a liquid variable displacement fluid transfer pump, which includes a pump body 110, a plunger 210, a slipper 220 and a control component.

[0027] A cylindrical drive chamber 111 is located at the center of the pump body 110. An eccentric wheel 120, capable of eccentric rotation around a central axis, is located inside the drive chamber 111. The eccentric wheel 120 is connected to an external drive motor via a transmission shaft. Multiple pump pipes 130 are radially and evenly distributed on the sidewall of the pump body 110. Each pump pipe 130 has a cylindrical sliding cavity 131 inside. An inlet pipe 140 and an outlet pipe 150 are located at the end of the pump pipe 130 furthest from the pump body 110. The inlet pipe 140 and outlet pipe 150 are coaxially arranged and both connect to the sliding cavity 131. A one-way valve is installed inside both the inlet pipe 140 and the outlet pipe 150, with opposite conduction directions.

[0028] The plunger 210 is slidably sealed inside the sliding cavity 131. The outer cylindrical surface of the plunger 210 and the inner wall of the sliding cavity 131 are dynamically sealed by a sealing ring. When the plunger 210 slides back and forth along the axis of the sliding cavity 131, the pumped liquid enters the sliding cavity 131 through the inlet pipe 140 and exits the sliding cavity 131 through the outlet pipe 150 under the action of the check valves in the inlet pipe 140 and the outlet pipe 150. During the process of the liquid being discharged through the outlet pipe 150, the sliding cavity 131 is under high pressure.

[0029] The plunger 210 has an axially oriented pressure guiding hole 211 inside, one end of which communicates with the sliding cavity 131. A spherical ball joint groove is provided at the center of the end of the plunger 210 near the eccentric wheel 120. A first elastic element 212 is provided between the end of the plunger 210 away from the eccentric wheel 120 and the outer end of the pump pipe 130. The first elastic element 212 is specifically a cylindrical helical compression spring, which constantly pushes the plunger 210 to move towards the eccentric wheel 120.

[0030] One end of the slide shoe 220 is integrally formed with a spherical head, which is rotatably fitted into a ball joint groove, forming a ball joint connection between the slide shoe 220 and the plunger 210. The other end of the slide shoe 220 has a planar structure and abuts against the outer circumferential surface of the eccentric wheel 120. A pressure balance chamber 221 is provided at the center of the end of the slide shoe 220 that abuts against the eccentric wheel 120. A damping hole is provided axially inside the slide shoe 220. One end of the damping hole communicates with the pressure balance chamber 221, and the other end communicates with the pressure guiding hole 211. When the sliding cavity 131 is under high pressure, the high-pressure liquid in the sliding cavity 131 enters the pressure balance chamber 221 through the pressure guiding hole 211 and the damping hole. When the pressure balance chamber 221 is under high pressure, it counteracts the positive pressure between the slide shoe 220 and the eccentric wheel 120.

[0031] The control component is integrated inside the slipper 220. This component is used to detect the pressure difference between the pressure balance chamber 221 and the sliding chamber 131 in real time, and adjust the size of the damping orifice based on this pressure difference. Initially, the damping orifice is set to its maximum opening size, allowing the liquid inside the sliding chamber 131 to quickly enter the pressure balance chamber 221. The pressure balance chamber 221 responds quickly, and the positive pressure inside it counteracts the positive pressure between the slipper 220 and the eccentric wheel 120 surface, reducing wear between them. If wear occurs between the slipper 220 and the eccentric wheel 120, the pressure in the pressure balance chamber 221 decreases, and the pressure difference between the pressure balance chamber 221 and the sliding chamber 131 increases. At this time, the control component will reduce the size of the damping orifice, making it more difficult for the liquid to pass through the damping orifice. The static pressure support effect inside the pressure balance chamber 221 decreases, and the positive pressure of the slipper 220 on the eccentric wheel 120 increases, thereby preventing the liquid inside the pressure balance chamber 221 from continuing to leak.

[0032] In one embodiment, the control assembly includes a damping tube 310, a sensing drive element, and a damping plug 320. A cylindrical control cavity 222 is axially formed inside the slipper 220. The damping tube 310 is coaxially slidably disposed within the control cavity 222, with a gap between a portion of the outer wall of the damping tube 310 and the inner wall of the control cavity 222. A first connecting port 223 is formed on the end face of the control cavity 222 away from the eccentric wheel 120, connecting the control cavity 222 to the pressure guiding hole 211. Under the action of the damping tube 310, the liquid flowing through the pressure guiding hole 211 enters the interior of the damping tube 310 through the first connecting port 223. A second connecting port 224 is formed on the end face of the control cavity 222 near the eccentric wheel 120, connecting the control cavity 222 to the pressure balance chamber 221. The damping plug 320 is a cylindrical structure, coaxially fixed on the end face of the control cavity 222 near the eccentric wheel 120. The damping plug 320 includes a frustum structure and a cylindrical structure. The frustum structure has a large end and a small end. The large end of the frustum structure is coaxially fixedly connected to the cylindrical structure. The outer diameter of the large end of the frustum structure is the same as the outer diameter of the cylindrical structure. The frustum structure is located on the side away from the eccentric wheel 120, and the cylindrical structure is located on the side close to the eccentric wheel 120. The cylindrical structure is coaxially fixedly connected to the end face of the control cavity 222.

[0033] Furthermore, the outer diameter of the cylindrical structure in the damping plug 320 is slightly smaller than the inner diameter of the damping tube 310, ensuring that the entire damping plug 320 can be inserted into the damping tube 310. In the initial state, the small end of the frustum structure of the damping plug 320 is not inside the damping tube 310, and the opening of the damping tube 310 is at its maximum. When the damping tube 310 slides axially along the adjustment cavity 222, the insertion depth of the damping plug 320 into the damping tube 310 changes, thereby changing the effective area of ​​the end opening of the damping tube 310 being blocked, and realizing the adjustment of the opening size of the damping tube 310.

[0034] The sensing drive is disposed between the damping tube 310 and the regulating cavity 222. The sensing drive is used to sense the pressure difference between the inside of the damping tube 310 and the pressure balance chamber 221, and generate an axial driving force on the damping tube 310 when there is a pressure difference between the inside of the damping tube 310 and the pressure balance chamber 221, thereby driving the damping tube 310 to slide relative to the regulating cavity 222, thereby changing the size of the opening at the end of the damping tube 310.

[0035] In one embodiment, the sensing actuator includes a driving ring 330. The driving ring 330 is coaxially fixedly sleeved on the outer wall of the damping tube 310, and a dynamic seal is achieved between the outer circumferential surface of the driving ring 330 and the inner wall of the control cavity 222 through a sealing ring. Multiple radial sensing holes 3111 are provided on the side wall of the damping tube 310. All sensing holes 3111 are located on the side of the driving ring 330 away from the damping plug 320, connecting the interior of the damping tube 310 with the side of the driving ring 330 away from the damping plug 320. This allows the two sides of the driving ring 330 to experience a pressure difference along its axial direction. When a pressure difference exists on both sides of the driving axis, the driving ring 330 moves along its own axial direction, thereby causing the damping tube 310 to move relative to the control cavity 222 along its own axial direction.

[0036] In one embodiment, the control component further includes a second elastic element 340; the second elastic element 340 is specifically a cylindrical helical compression spring, one end of the compression spring abuts against the drive ring 330, and the other end of the compression spring abuts against the end of the control cavity 222 near the damping plug 320. The compression spring is always in a compressed state and has a tendency to drive the damping tube 310 to move away from the eccentric wheel 120. When there is a pressure difference on both sides of the drive ring 330 axis, the compression spring and the pressure difference together form a force balance system for the damping tube 310, thereby ensuring that the damping tube 310 can move smoothly along its own axis.

[0037] In one embodiment, the control component further includes a compensation unit; the compensation unit is integrated inside the control cavity 222 and is connected to the damping tube 310 in a transmission manner. The compensation unit is used to synchronously adjust the contact normal pressure between the slipper 220 and the eccentric wheel 120 when the damping tube 310 slides axially due to the wear of the slipper 220, and automatically compensate for the gap caused by wear.

[0038] Furthermore, the damping tube 310 is divided into a first section 311 and a second section 312 arranged coaxially. The first section 311 is arranged close to the eccentric wheel 120, and the second section 312 is arranged away from the eccentric wheel 120. The rear end of the first section 311 is coaxially inserted into the front end of the second section 312, and the two can slide and rotate relative to each other. The drive ring 330 is fixedly sleeved on the outer wall of the first section 311; when the first section 311 slides towards the eccentric wheel 120 under the action of pressure difference, the second section 312 slides away from the eccentric wheel 120; the compensation unit includes a compensation rod 350, one end of the compensation rod 350 is slidably inserted into the end of the second section 312 away from the first section 311, the other end of the compensation rod 350 extends axially backward, the other end of the compensation rod 350 passes through the end face of the control cavity 222 and extends out of the outside of the slipper 220, the compensation rod 350 is set in a stepped shape, a push spring 360 is provided between the step of the compensation rod 350 near the first section 311 and one end of the second section 312, the push spring 360 maintains its original length when the second section 312 does not move relative to the control cavity 222, and the compensation rod 350 contacts the ball joint groove. When the second segment 312 moves away from the eccentric wheel 120, the compensating push rod 350 extends backward in sync. The end of the compensating push rod 350 can abut against and squeeze the inner wall of the ball joint groove at the end of the plunger 210, thereby generating a reverse force to push the entire slipper 220 to move towards the eccentric wheel 120, thus compensating for the wear gap.

[0039] In one embodiment, the compensation unit further includes a transmission component disposed between the first segment 311 and the second segment 312. The transmission component is used to convert the axial movement of the first segment 311 toward the eccentric wheel 120 into the axial movement of the second segment 312 away from the eccentric wheel 120, thereby realizing the reverse synchronous transmission between the first segment 311 and the second segment 312.

[0040] In one embodiment, the transmission component includes a one-way gear 410, a connecting gear ring 420, a connecting ring 430, and a guide. The connecting ring 430 is coaxially and slidably connected to the outer surface of the first segment 311 via a spline, and the connecting ring 430 is located on the side away from the plunger 210. An external thread is provided on the outer circumferential surface of the connecting gear ring 420, and an internal thread is provided on the inner wall of the regulating cavity 222. The external thread of the connecting gear ring 420 is threadedly connected to the internal thread on the inner wall of the regulating cavity 222. The diameter of the second segment 312 is larger than the diameter of the first segment 311, and an annular stepped surface is formed between the second segment 312 and the first segment 311. The connecting gear ring 420 abuts against the end face of the second segment 312 near the first segment 311. The connecting gear ring 420 is coaxially sleeved on the outside of the connecting ring 430. The one-way gear 410 is disposed between the inner circumferential surface of the connecting gear ring 420 and the outer circumferential surface of the connecting ring 430, allowing the connecting ring 430 to drive the connecting gear ring 420 to rotate in only one direction. The guide is disposed between the drive ring 330 and the inner wall of the regulating cavity 222. The guide is used to guide the first segment 311 to rotate circumferentially when it slides axially toward the eccentric wheel 120. Then, through the transmission of the one-way gear 410, the connecting gear ring 420 and the connecting ring 430, the second segment 312 moves away from the eccentric wheel 120.

[0041] In one embodiment, the guide includes a guide rod 440 and a guide groove 450; the guide groove 450 is inclinedly formed on the outer side wall of the drive ring 330, and its axis forms a certain angle with the axis of the drive ring 330; one end of the guide rod 440 is fixedly set on the inner side wall of the control cavity 222, and the other end is slidably embedded in the guide groove 450; when the drive ring 330 slides axially, the guide rod 440 slides relative to the guide groove 450, thereby driving the first segment 311 to generate circumferential rotation.

[0042] In one embodiment, the axis of the compensating push rod 350 is parallel to and spaced apart from the axis of the damping tube 310; in the rotation direction of the eccentric wheel 120, the compensating push rod 350 is located upstream of the movement trajectory of the damping tube 310 axis, so as to attach... Figure 4 Taking the perspective shown as an example, the eccentric wheel 120 rotates eccentrically clockwise. The axis of the compensating push rod 350 is located to the right of the axis of the damping tube 310, ensuring that the reaction force of the compensating push rod 350 on the plunger 210 can generate a torque along the rotation direction of the eccentric wheel 120. In the rotation direction of the eccentric wheel 120, the front end of the slipper 220 always contacts the surface of the eccentric wheel 120 first, thereby ensuring that the slipper 220 can stably squeeze the eccentric wheel 120 at each position of contact with the eccentric wheel 120.

[0043] Based on the above embodiments, the operating principle and working process of a liquid variable displacement fluid transfer pump provided by this invention are as follows: An external drive motor drives an eccentric wheel 120 to rotate eccentrically within the drive chamber 111 via a transmission shaft. Under the push of the first elastic element 212, the plunger 210 is always in contact with the outer circumference of the eccentric wheel 120 via the slipper 220. As the eccentric wheel 120 rotates, the plunger 210 reciprocates linearly within the sliding chamber 131. When the plunger 210 moves closer to the eccentric wheel 120, the volume of the sliding chamber 131 increases, generating negative pressure and completing the liquid suction process. When the plunger 210 moves away from the eccentric wheel 120, the volume of the sliding chamber 131 decreases, and the liquid is pressurized and discharged, completing the liquid discharge process.

[0044] The high-pressure liquid in the sliding cavity 131 enters the damping tube 310 through the pressure guide hole 211 and the first connecting port 223, and then flows into the pressure balance chamber 221 through the second connecting port 224. The high-pressure liquid generates an upward static pressure on the slipper 220 in the pressure balance chamber 221, which offsets most of the hydraulic pressure in the sliding cavity 131, so that a small lubrication gap is maintained between the slipper 220 and the eccentric wheel 120, realizing static pressure support and greatly reducing friction and wear.

[0045] In the initial state, the opening size of the end of the damping tube 310 is set to the maximum, at which time the high-pressure liquid in the sliding cavity 131 can quickly enter the pressure balance chamber 221; when the bottom of the slipper 220 is worn, the liquid inside the pressure balance chamber 221 leaks, and the pressure in the pressure balance chamber 221 drops, causing the pressure on the side of the drive ring 330 near the damping plug 320 to be lower than the pressure on the side away from the damping plug 320. By setting multiple sensing holes 3111 on the damping tube 310 and limiting the relative position of the sensing holes 3111 and the drive ring 330, it is ensured that the pressure on the side of the drive ring 330 away from the damping plug 320 is equal to the pressure in the sliding cavity 131. After the pressure difference on both sides of the drive ring 330 increases, the drive ring 330 drives the first section 311 damping tube 310 to slide towards the eccentric wheel 120, which increases the amount of damping plug 320 inserted into the damping tube 310. The effective flow area of ​​the opening at the end of the damping tube 310 decreases, which increases the difficulty for the liquid to pass through the damping hole. The static pressure support effect inside the pressure balance chamber 221 decreases, and the positive pressure of the slipper 220 on the eccentric wheel 120 increases, thereby preventing the liquid inside the pressure balance chamber 221 from continuing to leak.

[0046] As the wear of the slipper 220 increases, and the first section 311 damping tube 310 slides towards the eccentric wheel 120, the guide rod 440 slides along the guide arc groove 450, driving the first section 311 to rotate circumferentially. The first section 311 drives the connecting ring 430 to rotate via a spline, and the connecting ring 430 drives the connecting gear ring 420 to rotate via a one-way gear 410. Since the connecting gear ring 420 is threadedly connected to the inner wall of the regulating cavity 222, it will generate axial movement while rotating, moving away from the eccentric wheel 120, thereby pushing the second section 312 damping tube 310 to slide synchronously away from the eccentric wheel 120.

[0047] The second stage 312 drives the compensating push rod 350 to extend backward and abut against the inner wall of the ball joint groove of the plunger 210. Since the plunger 210 is stationary, the reaction force pushes the entire slipper 220 towards the eccentric wheel 120, thereby compensating for the clearance caused by wear and ensuring that the slipper 220 and the eccentric wheel 120 always maintain the optimal clearance. The one-way gear 410 ensures that the compensation action is only performed in one direction when wear increases, and the compensated position can be stably maintained without retraction due to pressure fluctuations.

[0048] Meanwhile, since the compensating push rod 350 is located on the right side of the axis of the damping tube 310 (as shown in the attached figure), Figure 4 Taking the perspective shown as an example, the reaction force generated will cause the slipper 220 to generate a pre-tilting torque along the rotation direction of the eccentric wheel 120, so that the front end of the slipper 220 always contacts the surface of the eccentric wheel 120 first, further improving the stability of the hydrostatic support and preventing the slipper 220 from tilting and wearing unevenly.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A liquid displacement type fluid transfer pump, characterized in that, include: The pump body has a drive chamber inside, and an eccentrically rotating eccentric wheel is provided inside the drive chamber; the pump body has a pump pipe along the radial direction of the pump body, and the pump pipe has a sliding chamber inside. A plunger is slidably disposed in the sliding cavity; a pressure guiding hole is provided inside the plunger, and the pressure guiding hole communicates with the sliding cavity; a ball groove is provided at the end of the plunger near the eccentric wheel; a first elastic element is provided between the end of the plunger away from the eccentric wheel and the end of the pump tube; The sliding shoe has a ball head at one end, which is located in the ball groove. The other end of the sliding shoe abuts against the eccentric wheel. A pressure balance chamber is provided at the end of the sliding shoe that abuts against the eccentric wheel. A damping hole is provided inside the sliding shoe to connect the pressure balance chamber with the pressure guide hole. A control component configured to adjust the size of the damping orifice based on the pressure difference between the pressure balance chamber and the sliding chamber.

2. The liquid displacement type fluid transfer pump according to claim 1, characterized in that: The control assembly includes a damping tube, a sensing drive, and a damping plug. A control cavity is provided inside the slip shoe. The damping tube is slidably disposed within the control cavity. A first communication port connecting to the pressure guide hole is provided at the end of the control cavity away from the eccentric wheel, and a second communication port connecting to the pressure balance chamber is provided at the end of the control cavity near the eccentric wheel. The damping plug is fixedly disposed at the end of the control cavity near the eccentric wheel. The damping plug can enter the interior of the damping tube. When the damping tube slides relative to the control cavity, the size of the opening at the end of the damping tube blocked by the damping plug can change. The sensing drive is used to sense the pressure difference between the interior of the damping tube and the interior of the pressure balance chamber, and the sensing drive can also drive the damping tube to slide relative to the control cavity when a pressure difference exists.

3. A liquid displacement type fluid transfer pump according to claim 2, characterized in that: The sensing drive includes a drive ring, which is coaxially and fixedly sleeved on the outer wall of the damping tube. The outer wall of the drive ring is sealed to the inner wall of the control cavity. A sensing hole is provided on the side wall of the damping tube, and the sensing hole is located on the side of the drive ring away from the damping plug.

4. A liquid displacement pump according to claim 2, characterized in that: The control component further includes a second elastic element, which is disposed between the end of the control cavity and the end of the damping tube.

5. A liquid displacement type fluid transfer pump according to claim 3, characterized in that: The control component further includes a compensation unit configured to adjust the contact pressure between the slipper and the eccentric wheel when the damping tube slides relative to the control cavity.

6. A liquid displacement pump according to claim 5, characterized in that: The damping tube is divided into a first section and a second section, which are coaxially connected. The first section is located close to the eccentric wheel, and the drive ring is fixedly mounted on the first section. When the first section moves closer to the eccentric wheel, the second section moves away from the eccentric wheel. The compensation unit includes a compensation rod, which is located on the second section. The compensation rod passes through the end of the control cavity away from the eccentric wheel, and the compensation rod can squeeze the ball joint groove of the plunger.

7. A liquid displacement pump according to claim 6, characterized in that: The compensation unit further includes a transmission component, which is used to convert the first segment of motion approaching the eccentric wheel into the second segment of motion moving away from the eccentric wheel.

8. A liquid displacement pump according to claim 7, characterized in that: The transmission component includes a one-way gear, a connecting gear ring, a connecting ring, and a guide; the connecting ring is coaxially slidably connected to the outer surface of the first segment, and the connecting gear ring is threadedly connected to the inner sidewall of the adjustment cavity; the diameter of the second segment is larger than the diameter of the first segment, the connecting gear ring abuts against the end face of the second segment, the connecting gear ring is coaxially disposed outside the connecting ring, and the one-way gear is disposed between the connecting gear ring and the connecting ring; the guide is used to guide the first segment to rotate when the first segment approaches the eccentric wheel.

9. A liquid displacement type fluid transfer pump according to claim 8, characterized in that: The guide includes a guide rod and a guide arc groove. The guide arc groove is disposed on the outer wall of the drive ring. The guide rod is fixedly disposed on the side wall of the control cavity and slidably disposed in the guide arc groove.

10. A liquid displacement pump according to claim 6, characterized in that: The axis of the compensating top rod is parallel to and spaced apart from the axis of the damping tube. In the direction of rotation of the eccentric wheel, the compensating top rod is located upstream of the movement trajectory of the damping tube axis.

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