Booster master cylinder

Abstract

The present invention provides a booster master pump, belonging to the technical field of brake systems. It solves the existing problem of excessive oil pressure in the oil replenishment chamber, which generates braking resistance. The booster master pump comprises a pump body and a piston assembly disposed within the pump body. The inner cavity of the pump body is sequentially divided by the piston assembly into a brake chamber, an oil replenishment chamber, and an oil inlet chamber. A seal is connected to the piston assembly between the brake chamber and the oil replenishment chamber, enabling one-way flow of oil into the brake chamber. The pump body has an oil inlet connected to the oil inlet chamber on its side. The pump body also has an adjustment chamber, in which an adjustment valve core and an elastic member are disposed. The adjustment chamber is respectively connected to the brake chamber, the oil replenishment chamber, and the oil inlet. The adjustment valve core, under the action of the elastic force of the elastic member, can block the oil replenishment chamber from the oil inlet. Under the action of the oil pressure in the brake chamber, the adjustment valve core can overcome the elastic force of the elastic member and move to connect the oil replenishment chamber and the oil inlet. The booster master pump has the advantage of low braking resistance.

Description

Technical Field

[0001] The present invention belongs to the technical field of brake systems and relates to a booster master cylinder, in particular to a booster master cylinder in a vehicle brake system. Background Art

[0002] The master brake cylinder is a crucial component of the braking system. It typically consists of a pump body, a piston that divides the pump body's interior into independent chambers, and a pushrod assembly that connects to the foot pedal, which the user applies by depressing the pedal. To effectively brake, the master brake cylinder requires a sufficient supply of oil. However, existing pump bodies are designed with a uniform bore diameter, making it difficult to meet the demand for a small bore and large displacement.

[0003] To this end, the applicant designed a hydraulic brake master cylinder structure for an agricultural harvester and applied for a Chinese patent (its application number is: 201310098146.X; publication number is: CN103171542A). The hydraulic brake master cylinder structure includes a pump body, in which a cavity A, a cavity B, two two-step holes C and two two-step holes D are opened, wherein the cavity A and the cavity B are arranged at the upper part of the pump body, the two-step hole C is arranged at the rear part of the pump body, and the two-step hole D is arranged at the front part of the pump body, wherein the hole of the two-step hole D is The diameter of the second-step hole C is larger than that of the second-step hole C. Both chambers A and B have oil inlet holes, which are interconnected. A quick-fill valve assembly is installed in the oil inlet hole. A small piston is installed in the second-step hole C, and a large piston is installed in the second-step hole D. The front end of the large piston extends out of the second-step hole D and is equipped with a return spring. The front end of the small piston is not connected to the rear end of the large piston through threads. An oil outlet hole is opened on the rear side of the small piston. A steel ball screw is installed below the second-step hole C, and a steel ball is installed between the steel ball screw and the second-step hole C. The provision of the stepped hole increases the oil discharge capacity of this brake master cylinder.

[0004] Among existing large-displacement brake master cylinders, one type uses a piston to sequentially divide the cylinder's internal cavity into a brake chamber, a refill chamber, and an inlet chamber. The cross-sectional area of ​​the brake chamber is smaller than that of the inlet chamber. However, during actual braking, as the piston pushes, the refill chamber slowly replenishes oil into the brake chamber. This causes the oil pressure in the refill chamber to continuously increase, creating significant resistance to the movement of the piston and push rod, hindering braking. Summary of the Invention

[0005] The purpose of the present invention is to address the above-mentioned problems existing in the prior art and to propose a booster master pump to solve the problem of excessive oil pressure in the existing oil replenishment chamber causing braking resistance.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] The booster master pump includes a pump body and a piston assembly arranged in the pump body, the inner cavity of the pump body is divided into a brake chamber, an oil replenishing chamber and an oil inlet chamber in sequence by the piston assembly, the piston assembly between the brake chamber and the oil replenishing chamber is connected to a seal that allows oil to flow unidirectionally to the brake chamber, the side of the pump body has an oil inlet connected to the oil inlet chamber, and is characterized in that the pump body also has an adjusting chamber and the adjusting valve core and an elastic member are arranged in the adjusting chamber, the adjusting chamber is respectively connected to the brake chamber, the oil replenishing chamber and the oil inlet, the adjusting valve core can block the oil replenishing chamber and the oil inlet under the action of the elastic force of the elastic member, and the adjusting valve core can overcome the elastic force of the elastic member and move under the action of the oil pressure in the brake chamber to connect the oil replenishing chamber and the oil inlet.

[0008] In this booster master pump, a piston assembly is provided within the pump body, capable of forming a seal with the inner wall of the pump body. This separates the inner cavity of the pump body into a brake chamber and an oil inlet chamber, located on either side of the piston assembly. Furthermore, the outer wall of the central portion of the piston assembly is recessed relative to the inner wall of the pump body, thereby forming an oil replenishment chamber between the brake chamber and the oil inlet chamber. During braking, the piston assembly moves within the pump body, that is, from the oil inlet side to the oil outlet side, squeezing the oil replenishment chamber and the brake chamber, increasing the oil pressure in both. The oil in the oil replenishment chamber flows unidirectionally through the seal on the piston assembly into the brake chamber for replenishment. Consequently, the oil pressure in the brake chamber is not lower than that in the oil replenishment chamber, and can even be slightly higher. When the oil pressure in the brake chamber rises to and exceeds the critical value, the oil pressure can act on the regulating valve core in the regulating chamber connected to the brake chamber, pushing it to overcome the elastic force of the elastic part and move, so that the oil replenishing chamber and the oil inlet are connected. The oil in the oil replenishing chamber will flow to the oil inlet through the regulating chamber, reducing the oil pressure in the oil replenishing chamber while replenishing the oil at the oil inlet, reducing the braking resistance and increasing the braking force.

[0009] During the process of the piston assembly moving inward and draining the oil from the oil replenishing chamber, the oil pressure in the oil replenishing chamber will drop rapidly, while the brake chamber can be replenished with the oil in the oil replenishing chamber and the oil pressure will increase during the inward movement of the piston assembly. The oil pressure of the brake chamber will be more stable than that of the oil replenishing chamber. Compared with the solution of directly using the oil pressure in the oil replenishing chamber as the power source for opening the regulating valve core, the oil in the brake chamber is used as the power source for opening the regulating valve core. This can make the opening process of the regulating valve core faster, more stable and more continuous, keep the oil replenishing chamber in a state of rapid oil drainage, quickly reduce resistance, and thus improve the response speed, convenience and comfort of braking.

[0010] In the aforementioned booster master pump, the regulating chamber is cylindrical and communicates with the brake chamber via a brake hole, with the oil replenishing chamber via an oil through hole, and with the oil inlet via an oil inlet hole. One end of the brake hole is formed on the side wall of the regulating chamber, and a sealing ring is provided between the regulating valve core and the inner wall of the regulating chamber on both sides of the opening of the brake hole, separating the brake hole from the oil through hole and the oil inlet hole. The sealing ring independently separates the brake hole from the oil through hole and the oil inlet hole, preventing the oil in the brake chamber from communicating with the oil replenishing chamber or the oil inlet through the regulating chamber, thereby preventing the oil in the brake chamber from flowing back into the oil replenishing chamber or the oil inlet. This maintains the stability of the oil pressure in the brake chamber, makes the opening process of the regulating valve core more stable and continuous, keeps the oil replenishing chamber in a state of rapid oil discharge, quickly reduces resistance, and thereby improves the response speed, convenience, and comfort of braking.

[0011] In the above-mentioned booster master pump, the regulating valve core is cylindrical, one end of which is a sealing end that can block the oil replenishment chamber and the oil inlet. The outer side of the regulating valve core also has a protruding annular force-bearing portion, and the opening of the brake hole on the side wall of the regulating chamber is located between the force-bearing portion and the sealing end. The regulating valve core is cylindrical as a whole, so when the oil pressure in the brake chamber increases and enters the regulating chamber, it will act on the side of the protruding force-bearing portion toward the sealing end, so that the force on the regulating valve core in this direction is greater than the other direction. The difference in force area is used to make the force-bearing portion drive the regulating valve core to move away from the sealing end, so that the sealing end is away from the oil through hole or the oil inlet hole, so that the oil replenishment chamber and the oil inlet are connected through the regulating chamber, and rapid oil leakage is achieved. Here, the force area difference is used to realize the oil pressure pushing the regulating valve core, avoiding the influence of other factors and ensuring the stability of the opening control of the regulating valve core.

[0012] In the aforementioned boost master pump, the regulating chamber comprises a large hole and a small hole, both coaxially arranged and circular. The large hole has a larger diameter than the small hole, and the small hole is closer to the sealing end of the regulating valve core. An annular shoulder is formed on the sidewall of the regulating chamber where the large and small holes meet, and the opening of the brake hole is located between the shoulder and the force-bearing portion. The stepped hole design aligns the shape of the regulating chamber with the shape of the regulating valve core, facilitating the fit and sealing between the regulating valve core and the regulating chamber, improving the sealing effect, preventing oil in the brake chamber from flowing back into the oil inlet and oil replenishment chamber, and ensuring the stability of the regulating valve core's opening control.

[0013] In the aforementioned supercharging master pump, one end of the oil passage is formed on the regulating chamber, opposite the sealing end of the regulating valve core. The sealing end has a recessed sealing recess. A block-shaped sealing block is disposed within the sealing recess, partially extending from the sealing recess. The end of the sealing block facing the oil passage has a protruding annular sealing portion surrounding the oil passage. The protruding annular sealing portion seals the oil passage, thereby disconnecting the oil passage from the oil inlet. The elastic force of the elastic member compresses the sealing portion, achieving a better sealing effect. Even if the sealing portion experiences minor wear, a good sealing effect is maintained.

[0014] In the aforementioned boost master cylinder, a recessed spring hole is defined on the end surface of the regulating valve core opposite the sealing end. The elastic member is partially disposed within the spring hole. A side hole is also defined on the side of the regulating valve core, connecting the spring hole to the outside of the regulating valve core. The external port, oil inlet, and oil passage holes of the side hole are all located on the side of the sealing ring opposite the brake hole. By enabling the side hole to communicate with the oil inlet and oil passage holes, during the opening movement of the regulating valve core, the oil and air within the spring hole can achieve pressure equilibrium with the oil replenishment chamber or the oil inlet. This prevents the pressure within the spring hole from increasing during movement of the regulating valve core, hindering its movement. This ensures stable opening of the regulating valve core and improves oil discharge efficiency and brake response speed.

[0015] In the aforementioned booster master pump, the pump body has a connecting port extending through the end of the regulating valve core opposite the sealing end. A pressure cap is threadedly connected to the connecting port, and the end of the elastic member opposite the regulating valve core abuts against the pressure cap. By rotating the threaded pressure cap, the critical opening pressure of the regulating valve core can be adjusted, thereby adapting the structure to different usage environments.

[0016] Alternatively, in the aforementioned boost master pump, the pump body includes a barrel-shaped mounting seat, the sealed end of the regulating valve core extends into the mounting seat, and the oil passage hole extends through the closed end of the mounting seat. To facilitate processing, assembly, or replacement, a barrel-shaped mounting seat may be provided in the pump body, thereby achieving a large and small aperture configuration for the regulating chamber.

[0017] Compared with the existing technology, this booster master pump uses the oil in the brake chamber with higher and more stable oil pressure as the power source to open the regulating valve core. When the oil pressure in the brake chamber reaches the critical value, the regulating valve core is opened, and the oil in the oil replenishment chamber is quickly and stably discharged to the oil inlet, reducing the oil pressure in the oil replenishment chamber while replenishing the oil at the oil inlet, reducing the braking resistance and increasing the braking assist when changing direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1It is a schematic cross-sectional view of the first embodiment of the boosting master pump.

[0019] Figure 2 It is a schematic cross-sectional structural diagram of the first embodiment of the boost master pump from another perspective.

[0020] Figure 3 It is a schematic cross-sectional view of the second embodiment of the boosting master pump.

[0021] Figure 4 It is a schematic cross-sectional view of the third embodiment of the boost master pump.

[0022] In the figure, 1, pump body; 11, brake chamber; 12, oil replenishment chamber; 13, oil inlet chamber; 14, oil inlet port; 15, oil outlet port; 16, regulating chamber; 161, large hole; 162, small hole; 17, brake hole; 18, oil through hole; 19, oil inlet hole; 2, piston assembly; 21, piston body; 3, sealing element; 4, elastic element; 5, regulating valve core; 51, sealing end; 52, force-bearing part; 53, sealing concave hole; 54, sealing Sealing block; 541, sealing part; 55, spring hole; 56, side hole; 6, sealing ring; 7, shoulder; 8, pressure cap; 9, mounting seat; 10, push rod; 101, limit shoulder; 201, spring seat; 202, exhaust valve; 203, extrusion cylinder; 204, balancing valve; 205, bolt; 206, leather cup 1; 207, leather cup 2; 208, push rod hole; 209, retaining ring; 210, pressing sleeve; 211, dust cover. DETAILED DESCRIPTION

[0023] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0024] Example 1

[0025] like Figure 1 and Figure 2As shown, this booster master pump has a dual-cylinder structure, comprising a pump body 1 with a recessed inner cavity at one end, and a piston assembly 2 disposed within the inner cavity of the pump body 1. The inner cavity of the pump body 1 is sequentially divided by the piston assembly 2 into a brake chamber 11, an oil replenishment chamber 12, and an oil inlet chamber 13. The sidewalls of each of the three chambers are cylindrical. The diameter of the oil replenishment chamber 12 is the same as that of the oil inlet chamber 13, and both are larger than the diameter of the brake chamber 11. An oil outlet 15 communicating with the brake chamber 11 and an oil inlet 14 communicating with the oil inlet chamber 13 are formed through the side of the pump body 1. A seal 3 is connected to the piston assembly 2 between the brake chamber 11 and the oil replenishment chamber 12, which prevents oil from flowing in one direction toward the brake chamber 11. In this embodiment, the piston assembly 2 comprises a single-piece stepped columnar piston body 21 and an extrusion cylinder 203 bolted to the front end of the piston body 21. Three seals are formed between the outer side of the piston body 21 and the inner wall of the pump body 1, and all three seals are sealed with annular leather cups, namely the seal 3, leather cup 1 206, and leather cup 2 207. The leather cup as the seal 3 separates the inner cavity of the pump body at the inner end of the piston assembly 2 into a brake chamber 11, the seal 3 and leather cup 1 separate the oil replenishment chamber 12 adjacent to the brake chamber 11, and the leather cup 1 206 and leather cup 2 207 separate the oil inlet chamber 13. The three leather cups are set in the same direction, that is, the oil can only flow in one direction from the outer end to the inner end of the piston assembly 2. Although there is a gap between the outer side of the piston body 21 on the side of the leather cup 2 207 close to the inner cavity opening of the pump body 1 and the inner wall of the pump body 1, no oil will flow through it. The outer end surface of the piston body 21 has a recessed push rod hole 208. The booster master cylinder also includes a rod-shaped push rod 10, whose inner end surface is arc-shaped and extends into the push rod hole 208. The sidewall of the push rod hole 208 also has a recessed, annular retaining groove. A retaining spring 209 is disposed in the retaining groove, and the retaining spring 209 partially protrudes from the retaining groove. An annular pressing sleeve 210 is sleeved on the outer side of the inner end of the push rod 10. The outer side of the inner end of the push rod 10 also has a protruding retaining shoulder 101. The pressing sleeve 210 is positioned between the retaining shoulder 101 and the retaining spring 209, with its ends abutting against the retaining shoulder 101 and the retaining spring 209, respectively. The retaining effect of the pressing sleeve 210 and the retaining spring 209 on the push rod 10 ensures a stable connection to the piston body 21 and prevents significant relative movement. A deformable cylindrical dust cover 211 is connected between the inner cavity opening of the pump body 1 and the outer side of the push rod 10 extending out of the pump body 1. One end of the dust cover 211 is sleeved and clamped on the outer side of the pump body 1, and the other end is adhered to the outer side of the push rod 10.

[0026] The pump body 1 also has a cylindrical regulating chamber 16, which is connected to the brake chamber 11 through the brake hole 17, connected to the oil replenishment chamber 12 through the oil through hole 18, and connected to the oil inlet 14 through the oil inlet hole 19. The regulating chamber 16 is provided with an elastic member 4 and a regulating valve core 5 that can block the oil replenishment chamber 12 and the oil inlet 14 under the elastic force of the elastic member 4. The regulating valve core 5 can move under the oil pressure of the brake chamber 11 and connect the oil replenishment chamber 12 and the oil inlet 14. In this embodiment, the brake hole 17 and the oil through hole 18 are both straight holes, such as Figure 2 As shown, the oil inlet hole 19 is formed by three sub-holes connected in sequence; in actual processing, in order to avoid clogging due to the high viscosity of the oil after long-term use, the aperture sizes of the oil inlet hole 19 and the oil through hole 18 can be as large as possible while ensuring the sealing effect and structural stability.

[0027] Specifically, the adjustment chamber 16 is a stepped hole, comprising a coaxially arranged large hole 161 and a small hole 162, both of which are circular. The diameter of the large hole 161 is larger than that of the small hole 162. A circular stop 7 is formed on the sidewall of the adjustment chamber 16 at the junction of the large and small holes 161 and 162. A brake hole 17 is provided on the sidewall of the large hole 161, an oil inlet hole 19 is provided on the sidewall of the small hole 162, and an oil through hole 18 is provided at the end of the small hole 162 away from the large hole 161.

[0028] The regulating valve core 5 is cylindrical, with one end forming a sealing end 51 that blocks the oil replenishment chamber 12 from the oil inlet 14. This sealing end 51 extends into the small hole 162. The regulating valve core 5 also has a protruding, annular, force-bearing portion 52 on the outside of the large hole 161. One end of the brake hole 17 is located between the force-bearing portion 52 and the stop shoulder 7, and the end surface of the force-bearing portion 52 facing the brake hole 17 is flat. The regulating valve core 5 has recessed annular sealing grooves on its outer walls on both sides of the brake hole 17, each containing a sealing ring 6. One sealing groove is located outside the force-bearing portion 52. The sealing ring 6 in this sealing groove extends outward and tightly abuts against the sidewall of the large hole 161, forming a seal. The other sealing groove is located on the outer wall of the regulating valve core 5 between the brake hole 17 and the oil inlet 19. The sealing ring 6 in this sealing groove extends outward and tightly abuts against the sidewall of the small hole 162, forming a seal. The brake hole 17 is isolated by two sealing rings 6 on both sides of the brake hole 17 and is not connected with the oil inlet hole 19 and the oil through hole 18.

[0029] An oil-passing gap exists between the outer wall of the sealing end 51 and the wall of the small hole 162, allowing the oil inlet 19 to connect to the end of the sealing end 51. The end of the sealing end 51 has a recessed sealing hole 53, within which a block-shaped sealing block 54 is disposed, partially extending out of the sealing hole 53. The end of the sealing block 54 facing the oil through hole 18 has a protruding, annular sealing portion 541 surrounding the oil through hole 18. The end of the sealing block 54 facing the bottom of the sealing hole 53 also has a protruding, annular sealing portion 541. The two sealing portions 541 are identical in size.

[0030] The pump body 1 has a circular connection port extending through it at the end of the regulating valve core 5 opposite the sealing end 51. A pressure cap 8 is threadedly connected to the connection port. The regulating valve core 5 has a recessed spring hole 55 at the end opposite the pressure cap 8. The elastic member 4 is a spring, with one end resting against the bottom of the spring hole 55 and the other end extending out of the spring hole 55 and resting against the inner end of the pressure cap 8.

[0031] The bottom of the spring hole 55 also has a concave circular extension hole, and the side of the regulating valve core 5 is also provided with a side hole 56 that connects the extension hole to the outside of the regulating valve core 5. The outer port of the side hole 56 is located on the outer wall of the regulating valve core 5 between the sealing ring 6 and the oil inlet hole 19, and the brake hole 17 is located on the other side of the sealing ring 6.

[0032] During braking, the booster master cylinder, with push rod 10 acting on piston assembly 2, moves into pump body 1, that is, from oil inlet 14 toward oil outlet 15. This compresses oil chamber 12 and brake chamber 11 against piston assembly 2, increasing the oil pressure in both chambers. During this process, the rubber cup between oil chamber 12 and oil inlet chamber 13 remains sealed, meaning that the oil in these chambers does not flow through the rubber cup.

[0033] When the oil pressure in the oil replenishing chamber 12 increases, it will act on the inclined sealing petal on the outside of the leather cup serving as the seal 3, causing it to retract inward, and the oil in the oil replenishing chamber 12 will flow unidirectionally through the leather cup into the brake chamber 11 for unidirectional oil replenishment, so that the oil pressure in the brake chamber 11 will not be lower than the oil pressure in the oil replenishing chamber 12, and may even be slightly higher than the oil pressure in the oil replenishing chamber 12, so that the opening of the regulating valve core 5 is faster and more stable.

[0034] When the oil pressure in the brake chamber 11 rises to and exceeds the critical value, the oil pressure can act on the force-bearing part 52 of the regulating valve core 5 in the regulating chamber 16 connected to the brake chamber 11, and there is only a sealing ring 6 protruding on the outside of the regulating valve core 5 on the other side of the brake hole 17, and the force-bearing area is much smaller than the force-bearing area at the force-bearing part 52. The oil pushes the regulating valve core 5 to overcome the elastic force of the elastic member 4 and move toward the pressure cap 8, so that the sealing part 541 on the sealing block 54 leaves the oil through hole 18, and the oil through hole 18 is connected to the oil inlet hole 19 through the oil gap. The oil in the oil replenishing chamber 12 flows to the oil inlet 14 through the regulating chamber 16 and the oil inlet hole 19, reducing the oil pressure in the oil replenishing chamber 12 while replenishing the oil at the oil inlet 14, thereby reducing the braking resistance and increasing the braking assist.

[0035] After braking, the piston assembly 2 moves outward and resets, the oil replenishing chamber 12 increases in size, the oil pressure decreases rapidly, while the oil pressure in the oil inlet chamber 13 remains unchanged, and the oil in the oil inlet port 14 is replenished into the oil replenishing chamber 12 through the leather cup, so that the oil amount in the oil replenishing chamber 12 returns to its initial state.

[0036] In addition to the above technical measures, the present booster master pump includes a spring seat 201 positioned within the brake chamber 11 near the oil outlet 15 for seating the return spring that resets the piston assembly 2. An exhaust hole is provided on the sidewall of the regulating chamber 16 opposite the brake hole 17, connected to an exhaust valve 202. A balancing valve 204 is connected to the sidewall of the pump body. When the piston assembly 2 moves inward, the extrusion cylinder 203 moves with it and acts on the balancing valve 204, opening it and thereby interconnecting the two inner chambers of the dual-cylinder booster master pump. The specific structures of the spring seat 201, exhaust valve 202, extrusion cylinder 203, and balancing valve 204 are identical to those in the applicant's patented dual-displacement brake pump, patent number ZL202120104471.2.

[0037] The oil outlet 15 of the booster master pump is provided with an oil outlet valve core and an oil outlet spring. The side wall of the oil outlet hole close to the brake chamber 11 is provided with a protruding annular boss. The oil outlet valve core is pressed against the boss under the elastic force of the oil outlet spring and forms a seal. A through hole is opened on the oil outlet valve core to connect the inner hole of the boss with the oil outlet hole. There is an oil outlet gap between the outer side of the oil outlet valve core and the inner wall of the oil outlet hole. The structural design of the oil outlet valve core and the oil outlet spring is combined with the cylindrical oil outlet joint threadedly connected to the oil outlet 15 to achieve the effect of fast oil out and slow return.

[0038] Example 2

[0039] like Figure 3As shown, the technical solution of this embodiment is roughly the same as that of the first embodiment, except that: the portion of the pump body 1 used to open the regulating chamber 16 is tilted compared to the axis of the inner cavity of the pump body 1, and the oil inlet hole 19 is composed of two branch holes connected in sequence; the sealing member 3 can be a sealing element with an inclined sealing flap similar to a leather cup; the elastic member 4 can also be an elastic filler similar to rubber with elastic restoring force.

[0040] Example 3

[0041] like Figure 4 The technical solution of this embodiment is substantially the same as that of the first embodiment, except that: the inner end surface of the pressure cap 8 has a recessed spring recess, a cylindrical mounting seat 9 is provided in the pump body 1 opposite the pressure cap 8, the outer side of the mounting seat 9 is sealed against the inner wall of the pump body 1, the open end of the mounting seat 9 faces the pressure cap 8, and the inner diameter of the mounting seat 9 is smaller than the inner diameter of the pressure cap 8, that is, the inner hole of the mounting seat 9 forms a small hole 162, and the spring recess forms a large hole 161, the two ends of the regulating valve core 5 extend into the inner hole of the mounting seat 9 and the spring recess, respectively, and the other end of the elastic member 4 abuts against the bottom surface of the spring recess. There is a gap between the open end of the mounting seat 9 and the inner end of the pressure cap 8, and one end of the brake hole 17 obliquely opened in the pump body 1 is located at the gap between the mounting seat 9 and the pressure cap 8; the oil hole 18 extends through the closed end of the mounting seat 9, and the oil inlet hole 19 is opened through the side wall of the mounting seat 9.

[0042] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

Claims

1. A booster master pump, comprising a pump body (1) and a piston assembly (2) disposed in the pump body (1), wherein the inner cavity of the pump body (1) is sequentially divided by the piston assembly (2) into a brake chamber (11), an oil replenishing chamber (12), and an oil inlet chamber (13), a seal (3) is connected to the piston assembly (2) between the brake chamber (11) and the oil replenishing chamber (12) to enable oil to flow in one direction to the brake chamber (11), and an oil inlet (14) is provided on the side of the pump body (1) to communicate with the oil inlet chamber (13), characterized in that: The pump body (1) further comprises a regulating chamber (16) in which a regulating valve core (5) and an elastic member (4) are provided. The regulating chamber (16) is respectively connected to the brake chamber (11), the oil replenishing chamber (12) and the oil inlet (14). The regulating valve core (5) can block the oil replenishing chamber (12) and the oil inlet (14) under the elastic force of the elastic member (4). The regulating valve core (5) can overcome the elastic force of the elastic member (4) under the oil pressure of the brake chamber (11). The force moves and connects the oil replenishing chamber (12) and the oil inlet (14). The regulating chamber (16) is columnar and is connected to the brake chamber (11) through the brake hole (17), is connected to the oil replenishing chamber (12) through the oil through hole (18), and is connected to the oil inlet (14) through the oil inlet hole (19). One end of the brake hole (17) is opened on the side wall of the regulating chamber (16), and is located in the regulating valve core (5) and the regulating chamber (16) on both sides of the opening of the brake hole (17). A sealing ring (6) is provided between the walls to separate the brake hole (17) from the oil hole (18) and the oil inlet hole (19). The regulating valve core (5) is cylindrical, one end of which is a sealing end (51) that can block the oil replenishing chamber (12) and the oil inlet (14). The outer side of the regulating valve core (5) also has a protruding annular force-bearing portion (52). The opening of the brake hole (17) on the side wall of the regulating chamber (16) is located between the force-bearing portion (52) and the sealing end (51). The regulating valve core (5) has a concave spring hole (55) on the end surface of the other end relative to the sealing end (51), and the elastic member (4) is partially arranged in the spring hole (55). The side of the regulating valve core (5) is also provided with a side hole (56) for connecting the spring hole (55) to the outside of the regulating valve core (5). The outer port, oil inlet hole (19) and oil through hole (18) of the side hole (56) are all located on the other side of the sealing ring (6) relative to the brake hole (17).

2. The boost master cylinder according to claim 1, characterized in that: The regulating chamber (16) comprises a large hole (161) and a small hole (162) both of which are circular and arranged coaxially, and the aperture of the large hole (161) is larger than the aperture of the small hole (162). The small hole (162) is closer to the sealing end (51) of the regulating valve core (5) than the large hole (161). An annular shoulder (7) is formed on the side wall of the regulating chamber (16) at the connection between the large hole (161) and the small hole (162). The opening of the brake hole (17) is located between the shoulder (7) and the force-bearing portion (52).

3. The boost master cylinder according to claim 1 or 2, characterized in that: One end of the oil through hole (18) is opened on the regulating chamber (16) at an end portion relative to the sealing end (51) of the regulating valve core (5). The end portion of the sealing end (51) has a recessed sealing recess (53). A block-shaped sealing block (54) is arranged in the sealing recess (53), and the sealing block (54) partially protrudes from the sealing recess (53). One end of the sealing block (54) facing the oil through hole (18) has a protruding annular sealing portion (541) surrounding the oil through hole (18).

4. The boost master cylinder according to claim 1 or 2, characterized in that: The pump body (1) has a connecting port extending through the other end of the regulating valve core (5) relative to the sealing end (51), and a pressure cap (8) is threadedly connected to the connecting port. The other end of the elastic member (4) relative to the regulating valve core (5) abuts against the pressure cap (8).

5. The boost master cylinder according to claim 1 or 2, characterized in that: The pump body (1) includes a barrel-shaped mounting seat (9), the sealing end (51) of the regulating valve core (5) extends into the mounting seat (9), and the oil hole (18) is opened through the closed end of the mounting seat (9).

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