Booster assembly

Abstract

The utility model provides a booster assembly, and belongs to the technical field of brake equipment. The problems that an existing brake pump is high in replacement cost and inconvenient to replace are solved. The booster assembly comprises a shell, a push rod and a piston arranged in the shell, sealing is formed between the outer side of the piston and the shell, an oil inlet cavity is formed in the position, on the rear side of the piston, of the shell, an oil inlet hole and an oil return hole are formed in the shell, a cylindrical valve element and a rod-shaped linkage piece are further arranged in the shell, and the linkage piece is arranged in the shell. The two ends of the linkage piece act on the push rod and the valve element respectively, the push rod can drive the valve element to move backwards through the linkage piece so as to block the oil inlet hole and the oil inlet cavity, the push rod can drive the valve element to move forwards so as to enable the oil inlet hole to be communicated with the oil inlet cavity, and a mounting cavity is formed in the position, located on the front side of the piston, in the shell. The front side of the mounting cavity is open, a push rod is arranged in the mounting cavity, and the rear end of the push rod can abut against the front end of the piston. The booster assembly has the advantage of being convenient to replace.

Description

Technical Field

[0001] The utility model belongs to the technical field of braking equipment and relates to a booster assembly. Background Art

[0002] With the continuous development of the motor vehicle industry, the utilization rate of vehicles has been continuously improved, and people's requirements for the comfort and safety of vehicle use have also been continuously improved. The clutch and braking systems of vehicles play a very important role during the use of vehicles, and a brake pump is a device used to assist in operating the braking system of a vehicle.

[0003] Currently, a brake pump generally includes a pump body, a piston disposed in the pump body, and a push rod whose outer end is used to connect with a vehicle pedal. The piston can divide the inside of the pump body into an oil inlet chamber and an oil return chamber. An oil inlet and an oil return are respectively formed on the pump body and are communicated with the oil inlet chamber and the oil return chamber. An oil passage is also formed on the piston to communicate the oil inlet chamber and the oil return chamber. The inner end of the push rod extends into the pump body, and when the push rod moves inward, the inner end of the push rod can block the oil passage.

[0004] However, different usage requirements need corresponding brake pumps of different specifications. Since existing brake pumps are all of a complete integral structure, if a different brake pump needs to be replaced, the oil circuit needs to be blocked and the entire brake pump needs to be removed for replacement, which not only has a relatively high replacement cost but also is relatively inconvenient to replace. Summary of the Utility Model

[0005] The purpose of the present utility model is to address the above problems existing in the prior art and propose a booster assembly, which solves the problems of high replacement cost and inconvenience in replacing existing brake pumps.

[0006] The purpose of the present utility model can be achieved by the following technical solutions:

[0007] The booster assembly includes a housing, a push rod, and a piston disposed in the housing. A seal is formed between the outer side of the piston and the housing, and an oil inlet chamber is formed in the housing behind the piston. An oil inlet hole and an oil return hole are formed on the housing. It is characterized in that a cylindrical valve core and a rod-shaped linkage member are further disposed in the housing. The two ends of the linkage member respectively act on the push rod and the valve core. The push rod can drive the valve core to move backward through the linkage member to block the oil inlet hole and the oil inlet chamber, and the push rod can drive the valve core to move forward to communicate the oil inlet hole and the oil inlet chamber. An installation cavity is provided in front of the piston in the housing, the front side of the installation cavity is open, a push rod is disposed in the installation cavity, and the rear end of the push rod can abut against the front end of the piston.

[0008] This booster assembly needs to be used in conjunction with an ordinary brake pump. The brake pump is connected to the front side of the installation cavity of the housing, and the push rod is used as the push rod of the brake pump to push the piston in the brake pump to move. In the default state, the push rod moves outward, and drives the valve core to move in the same direction through the linkage. The oil inlet hole and the oil inlet cavity are blocked by the valve core, and no oil enters the oil inlet cavity. During operation, the push rod moves inward, and drives the valve core to move in the same direction through the linkage, connecting the oil inlet hole and the oil inlet cavity. The oil is transported from the oil inlet hole to the oil inlet cavity to provide assistance for the movement of the piston and the push rod. In this booster assembly, the booster assembly and the brake pump are separable. When replacing, only the brake pump part needs to be replaced, and the booster assembly is retained. The replacement is simple and the replacement cost is low. Furthermore, the connection between the brake pump and the booster assembly is an installation cavity with an open front side and the installation cavity is located in front of the piston, that is, the piston is sealed with the housing through the outside, dividing the inner cavity of the housing into an oil inlet cavity and an installation cavity. The oil inlet cavity is used for oil inlet, and there is no oil in the installation cavity, which can facilitate replacement and installation.

[0009] In the booster assembly described above, the oil inlet hole is connected to the outside of the valve core, and the side of the valve core is penetrated with an oil through hole. The outer wall of the valve core between the oil through hole and the oil inlet hole has a protruding annular sealing portion 1, and the inner wall of the shell has a corresponding protruding sealing portion 2. When the valve core moves, the sealing portion 1 and the sealing portion 2 can abut against each other and form a seal to block the oil through hole and the oil inlet hole. The valve core can move axially back and forth under the drive of the push rod. When the sealing portion 1 and the sealing portion 2 abut against each other, the two can block the oil through hole and the oil inlet hole, and the oil inlet hole is not connected with the oil inlet chamber. On the contrary, the sealing portion 1 and the sealing portion 2 are staggered, and the oil through hole and the oil inlet hole are connected, and the oil at the oil inlet hole flows into the oil inlet chamber through the oil through hole, providing assistance for the movement of the push rod and the piston.

[0010] In the above-mentioned booster assembly, a steering gear hole is also provided on the housing, and the steering gear hole is connected to the outside of the valve core. A steering hole is also provided through the side wall of the valve core. The steering hole and the above-mentioned oil through hole are respectively located on both sides of the oil inlet hole. When the valve core moves outward with the push rod, the oil inlet hole is connected to the steering gear hole through the gap between the outside of the valve core and the inner wall of the housing. When the valve core moves inward with the push rod, the oil inlet hole is connected to the steering gear hole through the oil through hole, the inner hole of the valve core and the above-mentioned steering hole in sequence. The connection between the oil inlet hole and the steering gear hole can supply oil to the steering gear at the same time. During the movement of the valve core, the oil inlet hole is connected to the steering gear hole through different oil paths, and the oil supply amount can be changed according to the different diameters of the steering hole.

[0011] In the above-mentioned booster assembly, a cylindrical first sliding sleeve and a first sliding sleeve spring are sleeved on the outer side of the push rod. A protruding blocking portion is provided on the outer side of the front end of the push rod. The two ends of the first sliding sleeve spring act on the first sliding sleeve and the rear end of the push rod respectively. The front end of the first sliding sleeve can abut against the blocking portion. A cylindrical second sliding sleeve and a second sliding sleeve spring are sleeved on the outer side of the valve core. The second sliding sleeve can axially reciprocate relative to the valve core and is axially limited outside the valve core. An annular snap ring is fixed on the outer side of the rear end of the valve core. The second sliding sleeve can abut against the snap ring under the elastic force of the second sliding sleeve spring. One end of the linkage is hinged to the piston, and the other end passes through the above-mentioned first sliding sleeve and is sleeved on the second sliding sleeve. One end of the linkage is hinged and fixed to the piston, so that when the push rod pushes the first sliding sleeve to move, it can drive the second sliding sleeve and the second valve core to move, realizing linkage.

[0012] In the above-mentioned booster assembly, a pressure relief hole communicating with the oil inlet cavity and the oil inlet hole is also penetrated through the housing, and a pressure relief valve that enables the oil to flow unidirectionally from the oil inlet cavity to the oil inlet hole is arranged in the pressure relief hole.

[0013] In the above-mentioned booster assembly, a spherical steel ball and a rod-shaped ejector rod are also arranged in the pressure relief hole. When the steel ball moves towards the oil inlet cavity, it can block the pressure relief hole. A conical cover is also sleeved outside the second valve core. The smaller-diameter end of the conical cover is tightly pressed between the second sliding sleeve and the second sliding sleeve spring. The larger-diameter end of the conical cover faces the ejector rod. The ejector rod is located between the conical cover and the steel ball, and when the conical cover moves towards the ejector rod, it can push the ejector rod and the steel ball to move away from the conical cover. The steel ball cooperates with the pressure relief valve to achieve double sealing at the pressure relief hole. The setting of the ejector rod allows the conical cover to push the steel ball to move to cancel the blockage at this place when the oil pressure in the oil inlet cavity is relatively high.

[0014] In the above-mentioned booster assembly, a recessed notch is provided at the rear end of the piston. The front end of the push rod extends into the notch and a seal is formed between the outer side of the push rod and the side wall of the notch. A one-way hole is penetrated through the end of the push rod obliquely relative to the axis. A one-way valve that enables the oil in the oil inlet cavity to flow unidirectionally into the notch is arranged in the one-way hole. A rod-shaped pushing member is also arranged in the one-way hole. The front end of the pushing member acts on the one-way valve, and the rear end of the pushing member can abut against the front end of the first sliding sleeve. When the oil pressure in the oil inlet cavity is relatively high, the first sliding sleeve pushes the pushing member to open the one-way valve, realizing the oil pressure balance between the oil inlet cavity and the notch, and ensuring the smooth movement of the push rod.

[0015] In the above booster assembly, the number of the push rod, piston, oil inlet chamber, oil inlet hole, oil return hole, valve core, linkage rod, push rod, and installation chamber is two, and they are respectively arranged in the shell correspondingly. A balance hole communicating the two oil inlet chambers is also provided in the shell, and balance valves are arranged at both ports of the balance hole. The same structure can also be applied to a double-chamber structure, that is, the shell has two independent chambers, and the structures of the push rod, piston, oil inlet chamber, oil inlet hole, oil return hole, valve core, linkage rod, push rod, and installation chamber are respectively arranged in the two chambers correspondingly and work independently. The two chambers are balanced through the balance hole and the balance valve.

[0016] Compared with the prior art, the booster assembly and the brake pump of the present invention can be separated. During replacement, only the brake pump part needs to be replaced, while the booster assembly is retained, and the replacement is simple and the replacement cost is low. Brief Description of the Drawings

[0017] Figure 1 is a schematic cross-sectional structure diagram of the first embodiment of the booster assembly in the initial state.

[0018] Figure 2 is a schematic cross-sectional structure diagram of the first embodiment of the booster assembly in the working state.

[0019] Figure 3 is a schematic cross-sectional structure diagram of the pressure relief valve in the initial state.

[0020] Figure 4 is a schematic cross-sectional structure diagram of the pressure relief valve when the steel ball is pushed open.

[0021] In the figure, 1. Shell; 2. Push rod; 3. Piston; 4. Oil inlet chamber; 5. Oil inlet hole; 6. Oil return hole; 7. Valve core; 8. Linkage part; 9. Installation chamber; 10. Push rod; 11. Oil passage hole; 12. Sealing part one; 13. Sealing part two; 14. Steering gear hole; 15. Steering hole; 16. Sleeve one; 17. Sleeve spring one; 18. Blocking part; 19. Sleeve two; 20. Sleeve spring two; 21. Snap ring; 22. Pressure relief hole; 23. Pressure relief valve; 24. Steel ball; 25. Thrust rod; 26. Pressure cover; 27. Notch; 28. One-way hole; 29. One-way valve; 30. Pushing part; 31. Brake pump. Detailed Description of the Embodiments

[0022] The following are specific embodiments of the present invention and in combination with the drawings, the technical solutions of the present invention will be further described, but the present invention is not limited to these embodiments.

[0023] Embodiment 1

[0024] As Figure 1 and Figure 2As shown in the figure, the booster assembly includes a housing 1, a push rod 2, a piston 3 disposed within the housing 1, and a cylindrical valve core 7. An oil inlet hole 5 and an oil return hole 6 are penetratingly formed in the housing 1. Inside the housing 1, a partition portion is provided on the inner side of the front part, dividing the front part of the inner cavity of the housing 1 into two cavities. The piston 3 and the valve core 7 are respectively disposed in the two cavities. A sealing is formed between the outer side of the piston 3 and the inner wall of the housing 1 by an annular leather cup, and an oil inlet cavity 4 is formed in the housing 1 behind the piston 3. The oil inlet cavity 4 is located at the rear part of the housing 1 and is connected to the inner hole of the valve core 7.

[0025] The front side of the housing 1 is open. A plug is hermetically provided at the front port corresponding to the position of the valve core 7. An installation cavity 9 recessed backward is formed corresponding to the position of the piston 3. A rod-shaped push rod 10 is disposed in the installation cavity 9, and the rear end of the push rod 10 can abut against the front end of the piston 3.

[0026] A rod-shaped linkage member 8 is also disposed in the oil inlet cavity 4. A cylindrical sliding sleeve one 16 and a sliding sleeve spring one 17 are sleeved on the outer side of the push rod 2. A protruding blocking portion 18 is provided on the outer side of the front end of the push rod 2. The two ends of the sliding sleeve spring one 17 respectively act on the sliding sleeve one 16 and the rear end of the push rod 2. The front end of the sliding sleeve one 16 can abut against the blocking portion 18. The rear end of the valve core 7 is located in the oil inlet cavity 4, and a cylindrical sliding sleeve two 19 and a sliding sleeve spring two 20 are sleeved on the outer side of the rear end of the valve core 7. The sliding sleeve two 19 can axially reciprocate relative to the valve core 7 and is axially limited outside the valve core 7. An annular snap ring 21 is fixed on the outer side of the rear end of the valve core 7. The sliding sleeve two 19 can abut against the snap ring 21 under the elastic force of the sliding sleeve spring two 20. One end of the linkage member 8 is hinged to the piston 3, and the other end passes through the sliding sleeve one 16 and is sleeved outside the sliding sleeve two 19. In this embodiment, a recessed bayonet is provided on the outer side of the sliding sleeve one 16, and a part of the side of the linkage member 8 extends into the bayonet; a recessed annular groove is provided on the outer side of the sliding sleeve two 19, and the other end of the linkage member 8 is U-shaped and correspondingly inserted into both sides of the annular groove.

[0027] The oil inlet hole 5 communicates with the outer side of the valve core 7. An oil through hole 11 is penetratingly formed in the side portion of the valve core 7. A protruding circular ring-shaped sealing portion one 12 is provided on the outer side wall of the valve core 7 between the oil through hole 11 and the oil inlet hole 5. A corresponding protruding sealing portion two 13 is provided on the inner wall of the housing 1. When the valve core 7 moves, the sealing portion one 12 and the sealing portion two 13 can abut against each other to form a seal to block the oil through hole 11 and the oil inlet hole 5. In this embodiment, the axial position of the oil through hole 11 is between the oil inlet hole 5 and the oil return hole 6. A protruding annular sealing step one is provided on the outer side surface of the valve core 7 on the side of the oil through hole 11 relative to the oil return hole 6. The shape of the protruding and concave of the sealing step one and the inner wall of the housing 1 cooperate such that when the valve core 7 moves backward, a gap communicating the oil through hole 11 and the oil return hole 6 is formed between the sealing step one and the inner wall of the housing 1. After the valve core 7 moves forward, a seal is formed between the sealing step one and the inner wall of the housing 1 to block the oil through hole 11 and the oil return hole 6.

[0028] The housing 1 is also provided with a steering gear hole 14 penetrating therethrough, and the steering gear hole 14 communicates with the outside of the spool 7. The side wall of the spool 7 is also provided with a steering hole 15 penetrating therethrough. The steering hole 15 and the oil passage hole 11 are respectively located on both sides of the oil inlet hole 5. On the outer side wall of the spool 7 between the steering hole 15 and the oil inlet hole 5, there is a sealing step two protruding in a ring shape. The shape of the sealing step two cooperates with the concave and convex shape of the inner wall of the housing 1, so that when the spool 7 moves backward, a gap communicating the oil inlet hole 5 and the steering gear hole 14 is formed between the sealing step two and the inner wall of the housing 1. When the spool 7 moves forward, the sealing step two abuts against the inner wall of the housing 1 and forms a seal. Here, the cooperation between the sealing step one and the sealing step two and the inner wall of the housing 1 is similar to the cooperation between the sealing portion one 12 and the sealing portion two 13.

[0029] A conical cover 26 in a conical cylinder shape is also sleeved on the outer side of the rear end of the spool 7. The smaller diameter end of the conical cover 26 is tightly pressed between the second sliding sleeve 19 and the second sliding sleeve spring 20, and the larger diameter end of the conical cover 26 is closer to the oil inlet hole 5 than the other end.

[0030] As Figure 3 and Figure 4 shown, the housing 1 is also provided with a pressure relief hole 22 communicating the oil inlet chamber 4 and the oil inlet hole 5. A pressure relief valve 23 that enables the oil to flow unidirectionally from the oil inlet chamber 4 to the oil inlet hole 5 is arranged in the pressure relief hole 22. At the end of the pressure relief hole 22 close to the oil inlet chamber 4, there are also arranged a spherical steel ball 24, a metal sheet in a ring shape, and a push rod 25 in a rod shape. The steel ball 24 is arranged between the metal sheet and the push rod 25. The side wall of the pressure relief hole 22 between the steel ball 24 and the push rod 25 has a convex shoulder protruding in a ring shape. The steel ball 24 can abut against the convex shoulder and block the inner hole of the convex shoulder. The push rod 25 is located between the conical cover 26 and the steel ball 24, and when the conical cover 26 moves towards the push rod 25, it can push the push rod 25 and the steel ball 24 to move away from the conical cover 26. In this embodiment, there is also a side hole communicating the oil inlet chamber 4 and the pressure relief hole 22 outside the push rod 25 to ensure that the oil leaks from the oil inlet chamber 4 into the pressure relief hole 22.

[0031] The rear end of the piston 3 has a recessed notch 27. The front end of the push rod 2 extends into the notch 27, and a seal is formed between the outer side of the push rod 2 and the side wall of the notch 27 through an annular sealing ring. The end of the push rod 2 is provided with a one-way hole 28 penetrating obliquely with respect to the axis. A one-way valve 29 that enables the oil in the oil inlet chamber 4 to flow unidirectionally into the notch 27 is arranged in the one-way hole 28. A pushing member 30 in a rod shape is also arranged in the one-way hole 28. The front end of the pushing member 30 acts on the one-way valve 29, and the rear end of the pushing member 30 can abut against the front end of the first sliding sleeve 16.

[0032] This booster assembly needs to be used in conjunction with a common brake pump 31. Connect the brake pump 31 to the front side of the installation cavity 9 of the housing 1, and use the push rod 10 as the push rod 2 of the brake pump 31 to push the piston 3 in the brake pump 31 to move.

[0033] As Figure 1 shown, in the default state, the push rod 2 moves backward, and the valve core 7 also moves backward. The first sealing part 12 and the second sealing part 13 abut against each other to form a seal, and the oil inlet hole 5 and the oil passage hole 11 are not connected. At the same time, the oil inlet hole 5 and the steering hole 15 are also blocked. The first sealing step is in a conducting state, and the oil fluid at the oil inlet hole 5 is sent to the steering gear hole 14 for use at the steering gear.

[0034] As Figure 2 shown, during operation, the push rod 2 moves forward, drives the valve core 7 to move in the same direction through the linkage 8, and the first sealing part 12 and the second sealing part 13 are staggered in position to achieve conduction. A seal is formed at the first sealing step, the oil inlet hole 5 and the oil passage hole 11 are connected, and the oil fluid is transported from the oil inlet hole 5 through the oil passage hole 11 and the inner hole of the valve core 7 to the oil inlet cavity 4 to provide assistance for the movement of the piston 3 and the push rod 2.

[0035] At the same time, the oil fluid also flows through the steering hole 15 to the steering gear hole 14. Here, the aperture of the steering hole 15 is smaller, so that the oil fluid supplied to the steering gear in the working state is less than that in the default state.

[0036] When the oil fluid in the oil inlet cavity 4 continuously rises, the pressure cover 26 moves towards the ejector rod 25 against the elastic force of the second sliding sleeve spring 20 and abuts against the rear end of the ejector rod 25, pushing the ejector rod 25 forward to push open the steel ball 24, so that the oil pressure in the oil inlet cavity 4 directly acts on the pressure relief valve 23. After the oil pressure exceeds the set pressure of the pressure relief valve 23, the pressure relief valve 23 is opened, and the oil fluid in the oil inlet cavity 4 flows out to the oil inlet hole 5 through the pressure relief hole 22 to achieve pressure relief. At the same time, the first sliding sleeve 16 moves forward, acts on the rear end of the pusher 30, and pushes the one-way valve 29 to open, so that the pressure balance is achieved between the notch 27 and the oil inlet cavity 4, ensuring the stability of the movement of the push rod 2.

[0037] Embodiment 2

[0038] The technical solution of this embodiment is generally the same as that of Embodiment 1, except that: there are two independent cavities in the housing 1, and the structures of the push rod 2, the piston 3, the oil inlet cavity 4, the oil inlet hole 5, the oil return hole 6, the valve core 7, the linkage rod 8, the push rod 10 and the installation cavity 9 are all provided at both cavities. A balance hole communicating the two oil inlet cavities 4 is also opened in the housing 1, and balance valves are provided at both ports of the balance hole. Here, the structures of the balance hole and the balance valve are prior arts and will not be elaborated.

[0039] The specific embodiments described herein are merely illustrative of the spirit of the present utility model. Those skilled in the art to which the present utility model pertains can make various modifications or supplements to the described specific embodiments or use similar means for substitution, but will not deviate from the spirit of the present utility model or exceed the scope defined by the appended claims.

Claims

1. A booster assembly, comprising a housing (1), a push rod (2) and a piston (3) disposed in the housing (1), wherein a seal is formed between the outer side of the piston (3) and the housing (1) and an oil inlet chamber (4) is formed in the housing (1) at the rear side of the piston (3), and an oil inlet hole (5) and an oil return hole (6) are provided on the housing (1), characterized in that: The housing (1) is also provided with a cylindrical valve core (7) and a rod-shaped linkage member (8). The two ends of the linkage member (8) act on the push rod (2) and the valve core (7) respectively. The push rod (2) can drive the valve core (7) to move backward through the linkage member (8) to block the oil inlet hole (5) and the oil inlet chamber (4). The push rod (2) can drive the valve core (7) to move forward to connect the oil inlet hole (5) and the oil inlet chamber (4). The housing (1) has an installation cavity (9) located in front of the piston (3). The front side of the installation cavity (9) is open. A push rod (10) is arranged in the installation cavity (9) and the rear end of the push rod (10) can abut against the front end of the piston (3); the push rod (2), the piston (3), the oil inlet cavity (4), the oil inlet hole (5), the oil return hole (6), the valve core (7), the linkage (8), the push rod (10) and the installation cavity (9) are two in number and are respectively arranged in the housing (1); a balancing hole connecting the two oil inlet cavities (4) is also provided in the housing (1), and a balancing valve is arranged at both ends of the balancing hole.

2. The booster assembly according to claim 1, characterized in that: The oil inlet hole (5) is connected to the outer side of the valve core (7), and an oil through hole (11) is formed through the side of the valve core (7). A protruding annular sealing portion (12) is provided on the outer wall of the valve core (7) between the oil through hole (11) and the oil inlet hole (5), and a corresponding protruding sealing portion (13) is provided on the inner wall of the housing (1). When the valve core (7) moves, the sealing portion (12) and the sealing portion (13) can abut against each other and form a seal to block the oil through hole (11) and the oil inlet hole (5).

3. The booster assembly according to claim 2, characterized in that: The housing (1) is also provided with a steering gear hole (14), the steering gear hole (14) being connected to the outer side of the valve core (7), and the side wall of the valve core (7) is also provided with a steering hole (15), the steering hole (15) and the above-mentioned oil through hole (11) being respectively located on both sides of the oil inlet hole (5), and when the valve core (7) moves outward along with the push rod (2), the oil inlet hole (5) is connected to the steering gear hole (14) through the gap between the outer side of the valve core (7) and the inner wall of the housing (1), and when the valve core (7) moves inward along with the push rod (2), the oil inlet hole (5) is connected to the steering gear hole (14) through the oil through hole (11), the inner hole of the valve core (7) and the above-mentioned steering hole (15) in sequence.

4. The booster assembly according to claim 1, 2 or 3, characterized in that: The outer side of the push rod (2) is sleeved with a cylindrical sliding sleeve (16) and a sliding sleeve spring (17); the outer side of the front end of the push rod (2) has a protruding blocking portion (18); the two ends of the sliding sleeve spring (17) act on the sliding sleeve (16) and the rear end of the push rod (2) respectively; the front end of the sliding sleeve (16) can abut against the blocking portion (18); the outer side of the valve core (7) is sleeved with a cylindrical sliding sleeve (19) and a sliding sleeve spring (21). 0), the second sleeve (19) can axially reciprocate relative to the valve core (7) and the second sleeve (19) is axially limited outside the valve core (7), an annular retaining ring (21) is fixed on the outer side of the rear end of the valve core (7), the second sleeve (19) can be pressed against the retaining ring (21) under the elastic force of the second sleeve spring (20), one end of the linkage member (8) is hinged on the piston (3), and the other end passes through the above-mentioned first sleeve (16) and is sleeved on the second sleeve (19).

5. The booster assembly according to claim 4, characterized in that: The housing (1) is also provided with a pressure relief hole (22) which is connected to the oil inlet chamber (4) and the oil inlet hole (5). The pressure relief hole (22) is provided with a pressure relief valve (23) which enables oil to flow from the oil inlet chamber (4) to the oil inlet hole (5) in one direction.

6. The booster assembly according to claim 5, characterized in that: A spherical steel ball (24) and a rod-shaped push rod (25) are also arranged in the pressure relief hole (22). When the steel ball (24) moves in the direction of the oil inlet chamber (4), it can block the pressure relief hole (22). A conical-cylindrical pressure cover (26) is also sleeved on the second valve core (7). The end with a smaller diameter of the pressure cover (26) is tightly pressed between the second sliding sleeve (19) and the second sliding sleeve spring (20). The end with a larger diameter of the pressure cover (26) faces the push rod (25). The push rod (25) is located between the pressure cover (26) and the steel ball (24). When the pressure cover (26) moves in the direction of the push rod (25), it can push the push rod (25) and the steel ball (24) to move in a direction away from the pressure cover (26).

7. The booster assembly according to claim 4, characterized in that: The rear end of the piston (3) has a recessed notch (27), the front end of the push rod (2) extends into the notch (27) and a seal is formed between the outer side of the push rod (2) and the side wall of the notch (27), the end of the push rod (2) is obliquely provided with a one-way hole (28) extending therethrough relative to the axis, the one-way hole (28) is provided with a one-way valve (29) which enables oil in the oil inlet chamber (4) to flow in one direction into the notch (27), the one-way hole (28) is also provided with a rod-shaped push member (30), the front end of the push member (30) acts on the one-way valve (29), and the rear end of the push member (30) can abut against the front end of the sliding sleeve (16).

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