Pressurizing brake master cylinder

Abstract

The utility model provides a supercharging brake master cylinder, and belongs to the technical field of brake systems. The problem that the critical pressure of opening of an adjusting valve element in an existing supercharging brake master cylinder cannot be adjusted is solved. The pressurizing brake master pump comprises a pump body and a columnar piston, an inner cavity of the pump body is sequentially divided into a brake cavity, an oil supplementing cavity and an oil inlet cavity by the piston from inside to outside, and an axial hole communicated with the brake cavity is formed in the inner end of the piston in the axial direction. A first side hole communicated with the oil supplementing cavity and the axial hole and a second side hole communicated with the oil inlet cavity and the axial hole are formed in the side portion of the piston, a valve element and a spring are arranged in the axial hole, the axial hole penetrates through the piston, the inner side of the outer end of the piston is in threaded connection with an adjusting seat, and the two ends of the spring abut against the valve element and the adjusting seat respectively. The outer end of the adjusting base is provided with an adjusting groove used for allowing a tool to be inserted and driving the adjusting base to rotate in the circumferential direction. The supercharging brake master cylinder has the advantage of being convenient to adjust.

Description

Technical Field

[0001] This utility model belongs to the field of braking system technology and relates to a booster brake master cylinder. Background Technology

[0002] The brake pump is one of the core components of the entire automotive braking system. Its main function is to convert the mechanical force generated when the driver presses the brake pedal into hydraulic energy, which is then transmitted to the brakes of each wheel through the brake fluid, thereby achieving vehicle deceleration or stopping.

[0003] For example, the applicant designed a vehicle brake booster pump and applied for a Chinese patent with application number 202410657488.9 and publication number CN118560438A. This vehicle brake booster pump includes a pump body and a piston assembly disposed within the pump body. The piston assembly sequentially divides the cavity inside the pump body into an oil inlet chamber, an oil replenishment chamber, and a braking chamber. The piston assembly enables the oil in the oil inlet chamber to flow unidirectionally to the oil replenishment chamber and vice versa. The piston assembly includes a piston rod with a first connecting hole, a second connecting hole, a third connecting hole, and a main chamber. The first connecting hole, the second connecting hole, and the third connecting hole are located along the direction from the braking chamber toward the oil inlet chamber. The piston rod is arranged in sequence, with the first connecting hole along the axial direction of the piston rod, and the second and third connecting holes both along the radial direction of the piston rod. The first connecting hole connects the braking chamber to the main chamber, the second connecting hole connects the oil replenishing chamber to the main chamber, and the third connecting hole connects the oil inlet chamber to the main chamber. The main chamber is provided with an adjusting valve core and an elastic element. Under the action of the elastic force of the elastic element, the adjusting valve core isolates the oil inlet chamber, the oil replenishing chamber, and the braking chamber from being connected through the main chamber. Under the action of the oil pressure in the braking chamber, the adjusting valve core can overcome the elastic force of the elastic element and move, so that the oil replenishing chamber is connected to the oil inlet chamber through the second connecting hole, the main chamber, and the third connecting hole.

[0004] The vehicle brake booster pump has the regulating valve core and elastic element both located in the piston rod, that is, inside the pump body, without occupying the external space of the pump body, making the overall size of the booster pump small and occupying little external space.

[0005] However, due to the built-in regulating valve core and elastic element, the critical pressure at which the regulating valve core opens cannot be adjusted after installation, making it inconvenient to use. Utility Model Content

[0006] The purpose of this invention is to address the aforementioned problems in the existing technology by proposing a booster brake master pump that solves the problem that the critical pressure for opening the regulating valve core cannot be adjusted in the existing booster brake master pump.

[0007] The objective of this utility model can be achieved through the following technical solutions:

[0008] A booster brake master cylinder includes a pump body and a cylindrical piston. The inner end of the piston extends into the pump body and divides the pump body cavity from the inside out into a brake chamber, a replenishing chamber, and an inlet chamber. The outer end of the piston extends out of the pump body. An axial hole communicating with the brake chamber is formed on the inner end of the piston. A side hole connecting the replenishing chamber and the axial hole and a side hole connecting the inlet chamber and the axial hole are formed on the side of the piston. A valve core and a spring are disposed in the axial hole. The axial hole penetrates the piston. An adjusting seat is threaded to the inner side of the outer end of the piston. The two ends of the spring abut against the valve core and the adjusting seat, respectively. An adjusting groove is formed on the outer end of the adjusting seat for inserting a tool and driving the adjusting seat to rotate circumferentially.

[0009] In this booster brake master cylinder, the structure of the valve core is basically the same as the applicant's prior art. Under the action of the spring force, the valve core abuts against the step formed in the axial hole. A seal is formed between the outer side of the inner end of the valve core and the hole wall of the axial hole, which always blocks the connection between the side hole one and the brake chamber. A seal is also formed between the outer side of the outer end of the valve core and the hole wall of the axial hole. Under the action of the spring force, the sealing position moves to the space between the side hole one and the side hole two, blocking the axial hole between them, thus blocking the connection between the oil replenishment chamber and the oil inlet chamber. When the inner end of the valve core is subjected to the oil pressure in the brake chamber and moves axially outward against the spring force, the sealing position moves to the other side of the side hole two, so that the oil replenishment chamber is connected to the oil inlet chamber through the side hole one, the axial hole, and the side hole two, thereby achieving pressure relief.

[0010] During operation, the hydraulic pressure within the braking chamber rises to a critical value, causing the valve core to move against the spring force, thus releasing pressure. When it is necessary to adjust the hydraulic critical value for valve core movement, a tool is inserted into the adjusting groove through the axial hole at the outer end of the piston. The adjusting seat is rotated circumferentially, allowing it to be screwed in or out along the thread. When the adjusting seat is screwed in, it approaches the valve core, compressing the spring and increasing its force, thus raising the hydraulic critical value for valve core opening. Conversely, when the adjusting seat is screwed out, the spring extends, reducing the force on the valve core and lowering the hydraulic critical value for valve core opening. The specific adjustment amount can be obtained through testing during the product testing phase.

[0011] In this booster brake master cylinder, the axial hole extends through the entire piston axially, and a hole is left inside the outer end of the piston for the installation of the adjustment seat. This allows the preload force of the spring on the valve core to be adjusted without removing the entire piston, making it more convenient to use.

[0012] In the aforementioned booster brake master cylinder, the axial bore includes a sealing hole and a threaded hole located inside the outer end of the piston. The sealing hole and the threaded hole are coaxially aligned and connected. The threaded hole is closer to the outer end of the piston than the sealing hole, and its diameter is larger than that of the sealing hole. The adjusting seat is cylindrical, with its inner end extending into the sealing hole. A circular sealing ring is fixed to the outer side of the inner end of the adjusting seat, and the outer side of the sealing ring abuts against the wall of the sealing hole to form a seal. The outer side of the outer end of the adjusting seat has a protruding circular adjusting part, which is threadedly connected to a threaded hole inside the piston, and its outer diameter is larger than that of the sealing hole. The axial bore located inside the outer end of the piston is a stepped bore, which prevents the sealing ring from being damaged by the threads of the threaded hole when the adjusting seat is installed. The step formed at the stepped bore limits the degree of screwing in the adjusting part, preventing the adjusting seat from being over-screwed in and affecting the normal use of the spring.

[0013] In the aforementioned booster brake master cylinder, the axial bore further includes a second threaded hole. The second threaded hole and the first threaded hole are coaxially aligned, and the second threaded hole is closer to the outer end of the piston than the first threaded hole. The diameter of the second threaded hole is larger than that of the first threaded hole. The booster brake master cylinder also includes a plug threadedly connected to the second threaded hole. The outer end of the plug extends beyond the piston, and the end face of the outer end of the plug is flat. The plug seals the port of the axial bore, preventing external impurities from entering the axial bore and affecting the adjustment of the adjusting seat. It also increases the strength of the piston's outer end. The flat outer end of the plug facilitates the connection between the piston and other transmission structures.

[0014] In the aforementioned booster brake master cylinder, the adjusting groove is a strip-shaped groove.

[0015] In another case, in one of the aforementioned booster brake master cylinders, the adjusting groove is a groove with a regular hexagonal cross-section.

[0016] Compared with existing technologies, this booster brake master cylinder has an axial hole that runs through the entire piston along the axial direction, and a hole is left in the outer end of the piston for the installation of the adjustment seat. This allows the preload force of the spring on the valve core to be adjusted without removing the entire piston, making it more convenient to use. Attached Figure Description

[0017] Figure 1 This is a cross-sectional structural schematic diagram of the booster brake master cylinder.

[0018] Figure 2This is a partial enlarged view of the booster brake master cylinder.

[0019] In the diagram, 1. Pump body; 11. Braking chamber; 12. Oil replenishing chamber; 13. Oil inlet chamber; 2. Piston; 21. Axial hole; 22. Side hole one; 23. Side hole two; 24. Sealing hole; 25. Threaded hole one; 26. Threaded hole two; 3. Valve core; 4. Spring; 5. Adjusting seat; 51. Adjusting groove; 52. Adjusting part; 6. Sealing ring; 7. Plug. Detailed Implementation

[0020] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0021] like Figure 1 As shown, this booster brake master cylinder includes a pump body 1 and a cylindrical piston 2. The inner end of the piston 2 extends into the pump body 1 and divides the inner cavity of the pump body 1 into a brake chamber 11, a replenishing chamber 12, and an inlet chamber 13 from the inside out. The outer end of the piston 2 extends out of the pump body 1. An axial hole 21 communicating with the brake chamber 11 is provided on the inner end of the piston 2. A side hole 22 communicating with the replenishing chamber 12 and the axial hole 21 and a side hole 23 communicating with the inlet chamber 13 and the axial hole 21 are provided on the side of the piston 2. A valve core 3 and a spring 4 are provided in the axial hole 21. The inner wall of the axial hole 21 has a protruding annular shoulder, which is located between the side hole 22 and the inner port of the axial hole 21. The valve core 3 abuts against the end face of the shoulder under the elastic force of the spring 4. An O-ring forms a seal between the outer side of the inner end of the valve core 3 and the wall of the axial hole 21, which always blocks the connection between the side hole 22 and the brake chamber 11. An annular seal is fixed to the outer side of the outer end of the valve core 3, and the seal forms a seal between the seal and the wall of the axial hole 21. Under the elastic force of the spring 4, the seal moves to the position between the side hole 22 and the side hole 23, blocking the axial hole 21 between them, thus blocking the connection between the oil replenishment chamber 12 and the oil inlet chamber 13. When the inner end of the valve core 3 is subjected to the oil pressure in the brake chamber 11, it moves axially outward against the elastic force of the spring 4, and the seal moves to the other side of the side hole 23, so that the oil replenishment chamber 12 is connected to the oil inlet chamber 13 through the side hole 22, the axial hole 21, and the side hole 23, thereby achieving pressure relief.

[0022] like Figure 2 As shown, the axial hole 21 penetrates the piston 2. The axial hole 21 includes a sealing hole 24, a threaded hole 1 25 and a threaded hole 26 located inside the outer end of the piston 2. The sealing hole 24, the threaded hole 1 25 and the threaded hole 26 are arranged adjacent to each other from the inside to the outside, and the diameter of the three holes increases one by one. The three holes are arranged on the same axis.

[0023] A cylindrical adjusting seat 5 is inserted into the outer end of the piston 2. The two ends of the spring 4 abut against the valve core 3 and the adjusting seat 5, respectively. An adjusting groove 51 is provided at the outer end of the adjusting seat 5 for inserting a tool and rotating the adjusting seat 5 circumferentially. The inner end of the adjusting seat 5 extends into the sealing hole 24. A circular sealing ring 6 is fixed to the outer side of the inner end of the adjusting seat 5, and the outer side of the sealing ring 6 abuts against the wall of the sealing hole 24 to form a seal. A circular adjusting part 52 protrudes from the outer side of the outer end of the adjusting seat 5. This adjusting part 52 is threaded into a threaded hole 25 inside the piston 2, and its outer diameter is larger than the diameter of the sealing hole 24. In this embodiment, the adjusting groove 51 is a strip-shaped groove, i.e., a slotted hole, and is opened on the end face of the outer end of the adjusting seat 5. Of course, depending on the needs, the adjusting groove 51 can also be a non-circular groove such as a hexagonal groove.

[0024] The booster brake master cylinder also includes a plug 7 threadedly connected to the threaded hole 26. The outer end of the plug 7 extends out of the piston 2. The outer side of the outer end of the plug 7 has a protruding annular flange. The end of the flange facing the pump body 1 abuts against the end face of the outer end of the piston 2. The two opposite sides of the flange are parallel planes. The end face of the outer end of the plug 7 is a plane.

[0025] When it is necessary to adjust the hydraulic critical value of the valve core 3 movement, use a wrench to hold the two opposite planes on the convex edge, rotate the plug 7 to disassemble, and then use a screwdriver or other tools to insert into the adjusting groove 51 from the port of the axial hole 21 at the outer end of the piston 2, and rotate the adjusting seat 5 circumferentially so that the adjusting seat 5 can be screwed in or out along the thread.

[0026] When the adjusting seat 5 is screwed in, it approaches the valve core 3, compressing the spring 4 and increasing the elastic force of the spring 4, thus increasing the hydraulic critical value for opening the valve core 3; conversely, when the adjusting seat 5 is screwed out in the opposite direction, the spring 4 extends, reducing the elastic force acting on the valve core 3, thus decreasing the hydraulic critical value for opening the valve core 3.

[0027] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A booster brake master cylinder, comprising a pump body (1) and a cylindrical piston (2), wherein the inner end of the piston (2) extends into the pump body (1) and sequentially divides the inner cavity of the pump body (1) into a brake chamber (11), a replenishing chamber (12) and an inlet chamber (13) from the inside out, the outer end of the piston (2) extends out of the pump body (1), the inner end of the piston (2) is provided with an axial hole (21) communicating with the brake chamber (11), the side of the piston (2) is provided with a side hole one (22) communicating with the replenishing chamber (12) and the axial hole (21) and a side hole two (23) communicating with the inlet chamber (13) and the axial hole (21), and a valve core (3) and a spring (4) are provided in the axial hole (21), characterized in that, The axial hole (21) passes through the piston (2). The piston (2) has an adjusting seat (5) threaded on the inner side of its outer end. The two ends of the spring (4) abut against the valve core (3) and the adjusting seat (5) respectively. The outer end of the adjusting seat (5) has an adjusting groove (51) for inserting a tool and driving the adjusting seat (5) to rotate circumferentially.

2. The booster brake master cylinder according to claim 1, characterized in that, The axial hole (21) includes a sealing hole (24) and a threaded hole (25) located inside the outer end of the piston (2). The sealing hole (24) and the threaded hole (25) are coaxially arranged and connected. The threaded hole (25) is closer to the outer end of the piston (2) than the sealing hole (24), and the diameter of the threaded hole (25) is larger than the diameter of the sealing hole (24). The adjusting seat (5) is cylindrical. The inner end of the adjusting seat (5) extends into the sealing hole (24). A circular sealing ring (6) is fixed on the outer side of the inner end of the adjusting seat (5). The outer side of the sealing ring (6) abuts against the hole wall of the sealing hole (24) and forms a seal. The outer side of the outer end of the adjusting seat (5) has a protruding circular adjusting part (52). The adjusting part (52) is threadedly connected to the threaded hole (25) inside the piston (2), and the outer diameter of the adjusting part (52) is larger than the diameter of the sealing hole (24).

3. A booster brake master cylinder according to claim 2, characterized in that, The axial hole (21) also includes a second threaded hole (26), which is coaxially arranged with the first threaded hole (25) and the second threaded hole (26) is closer to the outer end of the piston (2) than the first threaded hole (25). The diameter of the second threaded hole (26) is larger than the diameter of the first threaded hole (25). The booster brake master cylinder also includes a plug (7) threadedly connected to the second threaded hole (26). The outer end of the plug (7) extends out of the piston (2) and the end face of the outer end of the plug (7) is a plane.

4. A booster brake master cylinder according to claim 1, 2, or 3, characterized in that, The adjusting groove (51) is a strip groove.

5. A booster brake master cylinder according to claim 1, 2, or 3, characterized in that, The adjustment groove (51) is a groove with a regular hexagonal cross-section.

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