Self-compensating hydraulic pump

Abstract

The invention belongs to the technical field of hydraulic machinery, and particularly relates to a self-compensating hydraulic pump, a check valve assembly of the self-compensating hydraulic pump is arranged in a cavity of a plunger, a valve rod in the middle of a check valve can move up and down under the driving of hydraulic force, and when the hydraulic force of a third cavity is larger than that of a first cavity, the valve rod stably moves upwards under the action of the hydraulic force and a reset spring, and a valve is opened; and oil enters the first cavity from the third cavity, so that the oil enters a main oil cavity of the suspended pneumatic hydraulic cylinder through the first cavity through-flow hole. When the hydraulic pressure of the first cavity is larger than that of the third cavity, the valve rod moves downwards and closes the valve, and oil in the main oil cavity is prevented from flowing back. A shaft sleeve assembly and a sleeve assembly are assembled outside the plunger assembly, and a guiding effect is achieved for reciprocating motion of the plunger assembly. The structure is more integrated and reliable, the optimal working position of the suspension pneumatic hydraulic cylinder can be adjusted back when the vehicle posture is lowered under the condition that a hydraulic system is not additionally arranged, and the suspension pneumatic hydraulic cylinder has the advantages of being simple in structure, low in cost and the like. The device has a wide application prospect in the field of mining machinery.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic machinery, and in particular relates to a self-compensating hydraulic pump. Background Art

[0002] The suspension pneumatic hydraulic cylinder is a device that adjusts the vehicle suspension height and stiffness by compressing nitrogen and oil. It consists of an air chamber and an oil chamber. When the vehicle passes through an uneven road surface, the liquid will flow to control the position of the piston, thereby changing the stiffness of the suspension pneumatic hydraulic cylinder. The vehicle suspension height and stiffness are changed by adjusting the air pressure in the air chamber and the flow of the fluid. The initial installation position of the suspension pneumatic hydraulic cylinder needs to be optimally matched with stiffness and damping through theoretical calculations. At the same time, the dynamic and static stroke ratio of the wheel is taken into account. However, as the vehicle runs for a long time, the working fluid will drop and the gas pressure will change. This causes the working position of the suspension pneumatic hydraulic cylinder to deviate from the desired target height.

[0003] After adding the vehicle posture adjustment system, a constant balance position can be achieved, and the vehicle posture can also be adjusted according to the road surface. However, adding the system requires adding a power unit, an electronic control device, and a sensor, which will greatly increase the cost and is not suitable for the low-cost requirements in the mining field. After adopting the self-compensating hydraulic pump of the invention, it is only necessary to add a compensation chamber to the outside of the suspension pneumatic hydraulic cylinder, and this can be achieved by integrating the inlet and outlet oil channels. When the vehicle posture is lowered, the compensation pump is turned on by the trigger device, and oil is continuously sucked from the compensation chamber into the main oil chamber of the suspension pneumatic hydraulic cylinder until the suspension pneumatic hydraulic cylinder returns to the original balance position. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] The technical problem to be solved by the present invention is: in view of the shortcomings of the prior art, how to design a self-compensating hydraulic pump, which can effectively ensure that the suspension pneumatic hydraulic cylinder operates reliably in the best balance position. No additional vehicle posture adjustment system is required, the structure is simple, and the repair, maintenance and maintenance are convenient, and the adjustment effect is convenient and reliable.

[0006] (II) Technical solution

[0007] In order to solve the above technical problems, the present invention provides a self-compensating hydraulic pump, which comprises a plunger assembly (1), a sleeve assembly (2), a base assembly (3), a sleeve assembly (4), a check valve assembly (5), a flange pressure plate (20), a housing (7), and a gasket (8);

[0008] The self-compensating hydraulic pump is used to be installed in a suspension pneumatic hydraulic cylinder of a heavy-duty vehicle. A center hole is machined on the inner end surface of a bottom cover of the suspension pneumatic hydraulic cylinder, the self-compensating hydraulic pump is installed into the corresponding hole and fixedly connected, a compensation chamber (44) is added outside the cylinder barrel of the suspension pneumatic hydraulic cylinder, and a sufficient amount of oil is injected into the compensation chamber (44); a flow channel is provided between the compensation chamber (44) and the self-compensating hydraulic pump, so that the oil in the compensation chamber (44) is connected to the third chamber (43) of the self-compensating hydraulic pump;

[0009] After the self-compensating hydraulic pump is installed, three chambers are formed: a first chamber (41) connected to the main oil chamber of the suspension pneumatic hydraulic cylinder, a second chamber (42) formed by the plunger assembly (1) and the sleeve assembly (4), and a third chamber (43) connected to the compensation chamber;

[0010] The plunger (10) in the plunger assembly (1) is hollow in structure, with a small diameter flow hole at one end and a large diameter hole at the other end for mounting the check valve assembly (5). The valve seat (11) is mounted in the middle hole, and the valve seat (11) is machined with a flow hole in the radial direction. When the valve stem (12) of the check valve assembly (5) is opened, it is used to achieve the connection between the oil in the first chamber (41) and the third chamber (43), and at the same time, the opening of the valve stem (12) is also limited. A rectangular sealing groove is machined on the large diameter cylindrical surface of the plunger (10), and a radial small hole is machined in the middle of the plunger (10), so that the first chamber (41) and the third chamber (43) can be connected. The cavity (41) and the second cavity (42) are connected by oil; the first sleeve (13) is installed in the cavity of the second sleeve (14) by a tight fit, and axial positioning is achieved through the annular end surface of the first sleeve (13); after the plunger assembly (1) is installed in the inner hole of the sleeve assembly (4), reciprocating motion along the axial direction is achieved; the left end of the plunger assembly (1) is installed in the shaft sleeve assembly (2), and the base assembly (3) and the gasket (8) are installed in the other end of the sleeve assembly (4), and the external shell (7) and the nut (15) and the above components are fixed and packaged together by threads to achieve complete positioning in the axial and radial directions.

[0011] The interior of the plunger (10) is a hollow structure, and a thread is processed on the small diameter end for connection with a special tool when disassembling the plunger; the inner hole of the large diameter end is used to install the check valve assembly (5), and the middle hole is used to install the valve seat (11); the outer cylindrical surface of the large diameter part of the plunger (10) is processed with a rectangular groove, and the first protective ring, the first O-ring, and the second protective ring are installed in sequence, and cooperate with the inner hole of the sleeve assembly (4) to squeeze and deform the first O-ring; a radial small hole is processed in the middle of the plunger (10) to connect the first cavity and the second cavity.

[0012] The check valve assembly (5) comprises a valve stem (12), a sealing cone (16), a return spring (17), a valve cap (18), a valve body (19), and a rivet (20);

[0013] A small hole is processed in the middle of the valve stem (12), and the sealing cone (16) and the valve cap (18) are sequentially installed into the large diameter end of the valve stem. After the valve cap hole is aligned with the valve stem hole, a rivet is installed, and the two sides are fixedly connected by a riveting process; after the above components are installed into the valve body (19), the end of the valve stem with threads is sequentially installed with a reset spring (17) and a small nut (21); a rectangular groove is processed on the outer cylindrical surface of the valve seat, and a third protective ring, a second O-ring, and a fourth protective ring are sequentially installed in the groove, which cooperate with the inner hole of the plunger to squeeze and deform the second O-ring.

[0014] The sleeve assembly (4) comprises a first sleeve (13) and a second sleeve (14); rectangular sealing grooves are processed on the inner and outer cylindrical surfaces of the second sleeve, and a fifth protective ring, a third O-ring and a sixth protective ring are sequentially installed in the inner groove, and cooperate with the outer hole of the plunger (10) and the inner hole of the sleeve assembly, so that the third O-ring is squeezed and deformed to form a sealing effect.

[0015] The bottom of the first sleeve (13) is fitted into the base assembly (3). When the oil in the third chamber is sucked into the first chamber, a vacuum appears in the third chamber, and oil is replenished from the external compensation chamber. After the liquid flow stabilizes, the ball (23) automatically falls into the hole of the base (22) by its own weight, forming a one-way valve.

[0016] The middle part of the first sleeve (13) is processed with an annular end surface, which realizes the axial installation and positioning of the first sleeve after being installed in cooperation with the second sleeve (14).

[0017] The washer (8) has a rectangular groove processed on one end plane, which can form an oil flow channel after being installed in conjunction with the end surface of the first sleeve (13).

[0018] The outer hole and the inner hole cylindrical surface of the shaft sleeve assembly (2) are both processed with rectangular sealing grooves, and the outer sealing groove is filled with an O-ring, which cooperates with the inner hole of the second sleeve (14) to squeeze and deform the O-ring to achieve the purpose of sealing the oil; the inner groove is filled with the seventh protection ring, the fourth O-ring, and the eighth protection ring in sequence, which are installed in cooperation with the plunger to squeeze and deform the fourth O-ring to form a high-pressure sealing effect on the oil in the main oil chamber.

[0019] The shaft sleeve (24) has a rectangular groove machined on one end plane, and after being installed in conjunction with the large diameter end face of the plunger (10), the oil in the external compensation chamber flows into the groove of the shaft sleeve (24) through the annular gap between the outer shell and the sleeve.

[0020] The shell (25) is provided with radial small holes in the middle, through which the oil in the external compensation chamber can enter the annular gap between the shell and the sleeve assembly (4), and can also enter the rectangular groove of the washer (8) at the bottom of the sleeve; the other end of the shell is provided with an external thread, which can achieve complete axial and radial positioning of the plunger after being tightened with a large nut (26).

[0021] (III) Beneficial effects

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] (1) The present invention proposes a self-compensating hydraulic pump that can be integrated inside a suspension pneumatic hydraulic cylinder. The oil in the outer chamber of the self-compensating hydraulic pump is connected to the compensation chamber of the suspension pneumatic hydraulic cylinder, and the first chamber of the pump is connected to the main oil chamber of the suspension pneumatic hydraulic cylinder. The pump starts only when the working position of the suspension pneumatic hydraulic cylinder drops. When the working fluid in the main oil chamber of the suspension pneumatic hydraulic cylinder is at a normal level, the shock absorber valve stem will not touch the plunger of the pump. The first chamber of the plunger and the second chamber of the plunger are connected to the oil in the main oil chamber of the suspension pneumatic hydraulic cylinder, and their internal pressures remain the same. However, the plunger will always remain in a high position because the annular end face area of ​​the plunger in the second chamber is the largest. The liquid pressure from the bottom is greater than the liquid pressure applied by the oil in the main oil chamber to the end face of the plunger thread.

[0024] (2) When the liquid level in the main oil chamber of the suspension pneumatic hydraulic cylinder drops, the shock absorber rod inside the suspension pneumatic hydraulic cylinder moves downward, causing the pump plunger to move downward. At the same time, the oil pressure in the third chamber under the plunger increases, the check valve opens, and the oil is injected from the third chamber through pipe 1 into the main oil chamber of the suspension pneumatic hydraulic cylinder. When the suspension pneumatic hydraulic cylinder rebounds, the plunger moves upward under the action of the oil pressure in the annular second chamber of the pump. A vacuum is formed in the third chamber under the plunger, and at the same time, the ball moves upward, opening the base oil channel, and the third chamber is filled with oil from the compensation chamber. This process is repeated until the liquid in the main oil chamber of the suspension pneumatic hydraulic cylinder returns to its original equilibrium position.

[0025] (3) The self-compensating hydraulic pump proposed by the present invention, when the working position drops due to oil leakage or gas leakage, can keep the balance position of the suspension pneumatic hydraulic cylinder at the same position and the height of the vehicle bottom from the ground at the same level by replenishing oil from the compensation chamber without adding a vehicle posture adjustment hydraulic system. It has an automatic adjustment return function for the lowering of the vehicle posture. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1a and Figure 1b It is the main sectional view of the self-compensating hydraulic pump;

[0027] Figure 2 It is a top view of the self-compensating hydraulic pump;

[0028] Figure 3 This is the left view of the self-compensating hydraulic pump;

[0029] Figure 4 It is the main sectional view of the sleeve assembly;

[0030] Figure 5 It is the main sectional view of the plunger assembly;

[0031] Figure 6 This is a main sectional view of the check valve assembly;

[0032] Figure 7 It is the main sectional view of the base assembly;

[0033] Figure 8 It is the main sectional view of the sleeve assembly;

[0034] Fig. 9 It is the main sectional view of the pneumatic hydraulic cylinder assembly with integrated self-compensating hydraulic pump suspension;

[0035] In the figure: 01. Compensating hydraulic pump; 1. Plunger assembly; 2. Bushing assembly; 3. Base assembly; 4. Sleeve assembly; 5. Check valve assembly; 7. Housing; 8. Gasket; 10. Plunger; 11. Valve seat; 12. Valve stem; 13. First sleeve; 14. Second sleeve; 15. Nut; 16. Sealing cone; 17. Return spring; 18. Valve bonnet; 19. Valve body; 22. Base; 23. Ball; 24. Bushing; 25. Housing; 26. Large nut; 28. Flange pressure plate; 29. ​​Bolt; 30. Screw plug; 32. Shock absorber valve stem; 41. First chamber; 42. Second chamber; 43. Third chamber; 44. Compensating chamber; 45. Flow channel; 46. Main oil chamber of suspension pneumatic hydraulic cylinder. DETAILED DESCRIPTION

[0036] In order to make the purpose, content, and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below in conjunction with the accompanying drawings and examples.

[0037] In order to solve the above technical problems, the present invention provides a self-compensating hydraulic pump, which comprises a plunger assembly (1), a sleeve assembly (2), a base assembly (3), a sleeve assembly (4), a check valve assembly (5), a flange pressure plate (20), a housing (7), and a gasket (8);

[0038] The self-compensating hydraulic pump is used to be installed in a suspension pneumatic hydraulic cylinder of a heavy-duty vehicle. A center hole is machined on the inner end surface of a bottom cover of the suspension pneumatic hydraulic cylinder, the self-compensating hydraulic pump is installed into the corresponding hole and fixedly connected, a compensation chamber (44) is added outside the cylinder barrel of the suspension pneumatic hydraulic cylinder, and a sufficient amount of oil is injected into the compensation chamber (44); a flow channel is provided between the compensation chamber (44) and the self-compensating hydraulic pump, so that the oil in the compensation chamber (44) is connected to the third chamber (43) of the self-compensating hydraulic pump;

[0039] After the self-compensating hydraulic pump is installed, three chambers are formed: a first chamber (41) connected to the main oil chamber of the suspension pneumatic hydraulic cylinder, a second chamber (42) formed by the plunger assembly (1) and the sleeve assembly (4), and a third chamber (43) connected to the compensation chamber;

[0040] The plunger (10) in the plunger assembly (1) is hollow in structure, with a small diameter flow hole at one end and a large diameter hole at the other end for mounting the check valve assembly (5). The valve seat (11) is mounted in the middle hole, and the valve seat (11) is machined with a flow hole in the radial direction. When the valve stem (12) of the check valve assembly (5) is opened, it is used to achieve the connection between the oil in the first chamber (41) and the third chamber (43), and at the same time, the opening of the valve stem (12) is also limited. A rectangular sealing groove is machined on the large diameter cylindrical surface of the plunger (10), and a radial small hole is machined in the middle of the plunger (10), so that the first chamber (41) and the third chamber (43) can be connected. The cavity (41) and the second cavity (42) are connected by oil; the first sleeve (13) is installed in the cavity of the second sleeve (14) by a tight fit, and axial positioning is achieved through the annular end surface of the first sleeve (13); after the plunger assembly (1) is installed in the inner hole of the sleeve assembly (4), reciprocating motion along the axial direction is achieved; the left end of the plunger assembly (1) is installed in the shaft sleeve assembly (2), and the base assembly (3) and the gasket (8) are installed in the other end of the sleeve assembly (4), and the external shell (7) and the nut (15) and the above components are fixed and packaged together by threads to achieve complete positioning in the axial and radial directions.

[0041] The interior of the plunger (10) is a hollow structure, and a thread is processed on the small diameter end for connection with a special tool when disassembling the plunger; the inner hole of the large diameter end is used to install the check valve assembly (5), and the middle hole is used to install the valve seat (11); the outer cylindrical surface of the large diameter part of the plunger (10) is processed with a rectangular groove, and the first protective ring, the first O-ring, and the second protective ring are installed in sequence, and cooperate with the inner hole of the sleeve assembly (4) to squeeze and deform the first O-ring; a radial small hole is processed in the middle of the plunger (10) to connect the first cavity and the second cavity.

[0042] The check valve assembly (5) comprises a valve stem (12), a sealing cone (16), a return spring (17), a valve cap (18), a valve body (19), and a rivet (20);

[0043] A small hole is processed in the middle of the valve stem (12), and the sealing cone (16) and the valve cap (18) are sequentially installed into the large diameter end of the valve stem. After the valve cap hole is aligned with the valve stem hole, a rivet is installed, and the two sides are fixedly connected by a riveting process; after the above components are installed into the valve body (19), the end of the valve stem with threads is sequentially installed with a reset spring (17) and a small nut (21); a rectangular groove is processed on the outer cylindrical surface of the valve seat, and a third protective ring, a second O-ring, and a fourth protective ring are sequentially installed in the groove, which cooperate with the inner hole of the plunger to squeeze and deform the second O-ring.

[0044] The sleeve assembly (4) comprises a first sleeve (13) and a second sleeve (14); rectangular sealing grooves are processed on the inner and outer cylindrical surfaces of the second sleeve, and a fifth protective ring, a third O-ring and a sixth protective ring are sequentially installed in the inner groove, and cooperate with the outer hole of the plunger (10) and the inner hole of the sleeve assembly, so that the third O-ring is squeezed and deformed to form a sealing effect.

[0045] The bottom of the first sleeve (13) is fitted into the base assembly (3). When the oil in the third chamber is sucked into the first chamber, a vacuum appears in the third chamber, and oil is replenished from the external compensation chamber. After the liquid flow stabilizes, the ball (23) automatically falls into the hole of the base (22) by its own weight, forming a one-way valve.

[0046] The middle part of the first sleeve (13) is processed with an annular end surface, which realizes the axial installation and positioning of the first sleeve after being installed in cooperation with the second sleeve (14).

[0047] The washer (8) has a rectangular groove processed on one end plane, which can form an oil flow channel after being installed in conjunction with the end surface of the first sleeve (13).

[0048] The outer hole and the inner hole cylindrical surface of the shaft sleeve assembly (2) are both processed with rectangular sealing grooves, and the outer sealing groove is filled with an O-ring, which cooperates with the inner hole of the second sleeve (14) to squeeze and deform the O-ring to achieve the purpose of sealing the oil; the inner groove is filled with the seventh protection ring, the fourth O-ring, and the eighth protection ring in sequence, which are installed in cooperation with the plunger to squeeze and deform the fourth O-ring to form a high-pressure sealing effect on the oil in the main oil chamber.

[0049] The shaft sleeve (24) has a rectangular groove machined on one end plane, and after being installed in conjunction with the large diameter end face of the plunger (10), the oil in the external compensation chamber flows into the groove of the shaft sleeve (24) through the annular gap between the outer shell and the sleeve.

[0050] The shell (25) is provided with radial small holes in the middle, through which the oil in the external compensation chamber can enter the annular gap between the shell and the sleeve assembly (4), and can also enter the rectangular groove of the washer (8) at the bottom of the sleeve; the other end of the shell is provided with an external thread, which can achieve complete axial and radial positioning of the plunger after being tightened with a large nut (26).

[0051] Example 1

[0052] This embodiment provides a self-compensating hydraulic pump, which has a wide range of application prospects in the field of mining machinery. It can be used in the suspension adjustment device of heavy-duty vehicles. Figure 1a , Figure 1b and Fig. 9 As shown, a center hole is machined on the inner end face of the bottom cover, and after the self-compensating hydraulic pump is installed in the corresponding hole, the compensating pump 01 is fixedly connected with four bolts 29 and a flange pressure plate 28, and an O-ring is installed in the sealing groove to prevent the internal oil from leaking out. A compensation chamber 44 is added to the outside of the cylinder barrel, and a sufficient amount of oil is injected through the screw plug 30 of the compensation chamber cylinder barrel. The components between the compensation chamber 44 and the self-compensating hydraulic pump 01 need to be integrated with the design of a flow channel 45 so that the oil in the compensation chamber is connected to the outer chamber of the self-compensating hydraulic pump.

[0053] The top of the self-compensating hydraulic pump 01 is provided with a plunger 10 as a trigger device. The self-compensating hydraulic pump 01 works by the contact and collision between the end face of the shock absorber valve stem 32 and the plunger 10. The shock absorber valve stem 32 is installed at the center of the upper hinge of the hydraulic cylinder, and the self-compensating hydraulic pump 01 is installed at the center of the lower hinge of the hydraulic cylinder, and the two are opposite. When the working fluid in the main oil chamber 46 of the suspension pneumatic hydraulic cylinder is at a normal level, the shock absorber valve stem 32 will not touch the plunger 10 of the pump. When the working position of the suspension pneumatic hydraulic cylinder drops, the shock absorber valve stem moves downward, and when it touches the end face of the plunger, the compensation pump valve is opened, so that the oil enters the main oil chamber 46 of the suspension pneumatic hydraulic cylinder from the external compensation chamber 44. When the suspension pneumatic hydraulic cylinder rebounds, the compensation pump is closed, and the plunger 10 is slowly reset under the action of the hydraulic pressure. This is repeated until the liquid level in the main oil chamber 46 of the suspension pneumatic hydraulic cylinder returns to the original equilibrium position. The volume of oil added is the volume of oil corresponding to the height of the vehicle posture drop.

[0054] After the self-compensating hydraulic pump is installed, three chambers will be formed, the first chamber 41 connected to the main oil chamber, the annular chamber formed by the plunger assembly and the sleeve assembly is the second chamber 42, and the third chamber 43 connected to the compensation chamber. When the pump is closed, the plunger 10 is always in a high position because the area of ​​the second chamber is larger. When the pump is started, the plunger assembly moves downward, and when the hydraulic pressure of the third chamber is greater than that of the first chamber, the check valve stem 12 is opened, and the oil in the second and third chambers enters the main oil chamber through the first chamber.

[0055] When the shock absorber valve stem 32 moves upward, the oil pressure in the third chamber decreases and gradually forms a vacuum. At this time, the ball valve of the base assembly 3 opens, and the oil in the compensation chamber 44 fills the third chamber through the flow channel 45. The check valve closes the valve under the pressure of the second chamber. The plunger moves upward under the pressure of the second chamber, and the oil from the main oil chamber 46 passes through the first chamber to fill the second chamber of the annular chamber again. The plunger returns to the high position.

[0056] The sleeve assembly 4 is composed of a first sleeve 13 and a second sleeve 14. The first sleeve is fitted into the second sleeve cavity by matching, and the end face of the first sleeve realizes the position limit of the plunger's downward stroke. The shaft sleeve assembly is installed into the small diameter end of the plunger and is fixedly connected together by the housing 25 and the large nut 26. The position limit of the plunger's upward stroke is realized.

[0057] Sealing grooves are arranged between the matching surfaces of the first sleeve and the second sleeve, the matching surfaces of the first sleeve and the outer cylinder of the plunger, and the matching surfaces of the plunger and the second sleeve, so that the second cavity forms a closed pressure chamber.

[0058] The bottom of the sleeve assembly fits into the base assembly 3. A spherical countersunk hole is machined inside the base 22. The ball 23 cooperates with the spherical surface to form a one-way valve. When the oil in the third chamber is sucked into the first chamber, a vacuum appears in the third chamber, and oil is replenished from the external compensation chamber 44. After the liquid flow stabilizes, it automatically falls into the hole of the base 22 by its own weight.

[0059] The valve stem of the check valve assembly 5 is processed with a positioning hole in the middle, and the sealing cone 16 and the valve bonnet 18 are sequentially installed into the valve stem 12. After the valve bonnet hole is aligned with the valve stem hole, a rivet is installed, and the two sides are fixedly connected by a riveting process. The sealing cone fits tightly with the end face of the valve stem, the cylindrical surface of the valve stem, and the V-shaped conical surface of the valve seat to ensure the sealing performance when the valve is closed. The end of the valve stem with threads is sequentially installed with the reset spring 17 and the nut 15. When the valve stem 12 moves upward, the valve opens steadily and evenly under the action of the reset spring 17. When the valve stem contacts the limit valve seat, the valve is fully opened.

[0060] Sealing grooves are arranged between the outer cylindrical surface of the sleeve 24 and the mating surface of the housing 25, and between the inner cylindrical surface of the sleeve and the mating surface of the plunger 10. An O-ring is installed in the outer sealing groove, and the O-ring is squeezed and deformed in cooperation with the inner hole of the sleeve to achieve the purpose of sealing the oil. The first protection ring, the O-ring, and the second protection ring are installed in sequence in the inner groove, and are installed in cooperation with the plunger to squeeze and deform the O-ring, forming a high-pressure sealing effect on the oil in the main oil chamber 46.

[0061] The middle of the housing 25 is processed with radial flow holes, and the external compensation chamber oil can enter the annular gap between the housing and the sleeve assembly through these holes, and can also enter the square opening groove of the gasket at the bottom of the sleeve. The other end of the housing is processed with external threads, which are tightened with the large nut 26 to form a self-compensating hydraulic pump assembly module, which can be integrated and arranged in the actuator that needs to perform self-oil replenishment operation.

[0062] In summary, the present invention belongs to the field of hydraulic machinery technology, and specifically relates to a self-compensating hydraulic pump, which includes: a plunger assembly, a sleeve assembly, a base assembly, a sleeve assembly, a check valve assembly, a flange pressure plate, a housing, and a gasket; the check valve assembly is placed in the cavity of the plunger, and the valve stem in the middle of the check valve can move up and down under the drive of the hydraulic pressure. When the hydraulic pressure in the third cavity is greater than that in the first cavity, the valve stem steadily moves upward under the joint action of the hydraulic pressure and the return spring, and opens the valve, and the oil enters the first cavity from the third cavity, so that the oil enters the main oil cavity of the suspended pneumatic hydraulic cylinder through the flow hole of the first cavity. When the hydraulic pressure in the first cavity is greater than the hydraulic pressure in the third cavity, the valve stem moves downward and closes the valve to prevent the oil in the main oil cavity from flowing back. The outside of the plunger assembly is equipped with a sleeve assembly and a sleeve assembly to form a guiding effect for the reciprocating motion of the plunger assembly. The large cylindrical surface of the plunger assembly and the inner and outer cylindrical surfaces of the sleeve assembly are processed with sealing grooves, and O-rings and protective rings are installed in the grooves. The seal is squeezed through the matching surface, and the base and the ball act as a one-way valve under the action of hydraulic pressure. When there is hydraulic pressure in the second chamber and the third chamber, a closed pressure chamber can be formed. The above components are installed in the housing and fixed by nuts to form a self-compensating hydraulic pump module. The pump can be integrated inside the suspension pneumatic hydraulic cylinder. When the working position in the cavity drops, the check valve is opened by the trigger device, and oil is continuously sucked from the third chamber into the first chamber until the suspension pneumatic hydraulic cylinder returns to the original working position. The structure of the present invention is more integrated and reliable, and can realize the callback of the optimal working position of the suspension pneumatic hydraulic cylinder when the vehicle posture is lowered without adding a hydraulic system. It has the characteristics of simple structure and low cost. It has broad application prospects in the field of mining machinery.

[0063] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A self-compensating hydraulic pump, characterized in that: The self-compensating hydraulic pump comprises a plunger assembly (1), a sleeve assembly (2), a base assembly (3), a sleeve assembly (4), a check valve assembly (5), a flange pressure plate (20), a housing (7), and a gasket (8); The self-compensating hydraulic pump is used to be installed in a suspension pneumatic hydraulic cylinder of a heavy-duty vehicle. A center hole is machined on the inner end surface of a bottom cover of the suspension pneumatic hydraulic cylinder, the self-compensating hydraulic pump is installed into the corresponding hole and fixedly connected, a compensation chamber (44) is added outside the cylinder barrel of the suspension pneumatic hydraulic cylinder, and a sufficient amount of oil is injected into the compensation chamber (44); a flow channel is provided between the compensation chamber (44) and the self-compensating hydraulic pump, so that the oil in the compensation chamber (44) is connected to the third chamber (43) of the self-compensating hydraulic pump; After the self-compensating hydraulic pump is installed, three chambers are formed: a first chamber (41) connected to the main oil chamber of the suspension pneumatic hydraulic cylinder, a second chamber (42) formed by the plunger assembly (1) and the sleeve assembly (4), and a third chamber (43) connected to the compensation chamber; The plunger (10) in the plunger assembly (1) is hollow in structure, with a small diameter flow hole at one end and a large diameter hole at the other end for mounting the check valve assembly (5). The valve seat (11) is mounted in the middle hole, and the valve seat (11) is machined with a flow hole in the radial direction. When the valve stem (12) of the check valve assembly (5) is opened, it is used to achieve the connection between the oil in the first chamber (41) and the third chamber (43), and at the same time, the opening of the valve stem (12) is also limited. A rectangular sealing groove is machined on the large diameter cylindrical surface of the plunger (10), and a radial small hole is machined in the middle of the plunger (10), so that the first chamber (41) and the third chamber (43) can be connected. The cavity (41) and the second cavity (42) are connected by oil; the first sleeve (13) is installed in the cavity of the second sleeve (14) by a tight fit, and axial positioning is achieved through the annular end surface of the first sleeve (13); after the plunger assembly (1) is installed in the inner hole of the sleeve assembly (4), reciprocating motion along the axial direction is achieved; the left end of the plunger assembly (1) is installed in the shaft sleeve assembly (2), and the base assembly (3) and the gasket (8) are installed in the other end of the sleeve assembly (4), and the external shell (7) and the nut (15) and the above components are fixed and packaged together by threads to achieve complete positioning in the axial and radial directions.

2. The self-compensating hydraulic pump according to claim 1, characterized in that The interior of the plunger (10) is a hollow structure, and a thread is processed on the small diameter end for connection with a special tool when disassembling the plunger; the inner hole of the large diameter end is used to install the check valve assembly (5), and the middle hole is used to install the valve seat (11); the outer cylindrical surface of the large diameter part of the plunger (10) is processed with a rectangular groove, and the first protection ring, the first O-ring, and the second protection ring are installed in sequence, and cooperate with the inner hole of the sleeve assembly (4) to squeeze and deform the first O-ring; the middle part of the plunger (10) is processed with a radial small hole to connect the first cavity and the second cavity.

3. The self-compensating hydraulic pump according to claim 2, characterized in that: The check valve assembly (5) comprises a valve stem (12), a sealing cone (16), a return spring (17), a valve cap (18), a valve body (19), and a rivet (20); A small hole is processed in the middle of the valve stem (12), and the sealing cone (16) and the valve cap (18) are sequentially installed into the large diameter end of the valve stem. After the valve cap hole is aligned with the valve stem hole, a rivet is installed, and the two sides are fixedly connected by a riveting process; after the above components are installed into the valve body (19), the end of the valve stem with threads is sequentially installed with a reset spring (17) and a small nut (21); a rectangular groove is processed on the outer cylindrical surface of the valve seat, and a third protective ring, a second O-ring, and a fourth protective ring are sequentially installed in the groove, which cooperate with the inner hole of the plunger to squeeze and deform the second O-ring.

4. The self-compensating hydraulic pump according to claim 3, characterized in that: The sleeve assembly (4) comprises a first sleeve (13) and a second sleeve (14); rectangular sealing grooves are processed on the inner hole and outer hole cylindrical surfaces of the second sleeve, and the fifth protective ring, the third O-ring and the sixth protective ring are sequentially installed in the inner hole groove, which cooperate with the outer hole of the plunger (10) and the inner hole of the sleeve assembly, so that the third O-ring is squeezed and deformed to form a sealing effect.

5. The self-compensating hydraulic pump according to claim 4, characterized in that The bottom of the first sleeve (13) is fitted into the base assembly (3). When the oil in the third chamber is sucked into the first chamber, a vacuum appears in the third chamber, and oil is replenished from the external compensation chamber. After the liquid flow stabilizes, the ball (23) automatically falls into the hole of the base (22) by its own weight, forming a one-way valve.

6. The self-compensating hydraulic pump according to claim 5, characterized in that The middle part of the first sleeve (13) is processed with an annular end surface, which realizes the axial installation and positioning of the first sleeve after being installed in cooperation with the second sleeve (14).

7. The self-compensating hydraulic pump according to claim 6, characterized in that The washer (8) has a rectangular groove processed on one end plane, which can form an oil flow channel after being installed in conjunction with the end surface of the first sleeve (13).

8. The self-compensating hydraulic pump according to claim 7, characterized in that The shaft sleeve assembly (2) is processed with rectangular sealing grooves on the outer hole and the inner hole cylindrical surface. The outer sealing groove is filled with an O-ring, which cooperates with the inner hole of the second sleeve (14) to squeeze and deform the O-ring to achieve the purpose of sealing the oil; the inner groove is filled with the seventh protection ring, the fourth O-ring, and the eighth protection ring in sequence, which are installed in cooperation with the plunger to squeeze and deform the fourth O-ring to form a high-pressure sealing effect on the oil in the main oil chamber.

9. The self-compensating hydraulic pump according to claim 8, characterized in that The shaft sleeve (24) has a rectangular groove machined on one end plane. After being installed in cooperation with the large diameter end surface of the plunger (10), the oil in the external compensation chamber flows into the groove of the shaft sleeve (24) through the annular gap between the outer shell and the sleeve.

10. The self-compensating hydraulic pump of claim 98, wherein: The housing (25) is provided with radial small holes in the middle, through which the oil in the external compensation chamber can enter the annular gap between the housing and the sleeve assembly (4), and can also enter the rectangular groove of the washer (8) at the bottom of the sleeve; the other end of the housing is provided with an external thread, which can achieve complete axial and radial positioning of the plunger after being tightened with a large nut (26).

Images