Two-way supercharging brake master cylinder

Abstract

The utility model provides a two-way supercharging brake master cylinder, and belongs to the technical field of brake systems. The brake master cylinder solves the problem that an existing brake master cylinder is insufficient in use safety. The two-way pressurizing brake master pump comprises a pump body with a pump cavity, a piston assembly is arranged in the pump cavity, two oil inlet holes are formed in the top wall of the pump cavity, and a protruding oil storage wall is integrally arranged on the top surface of the pump body. A partition wall which is located between the two oil inlet holes and divides a cavity on the inner side of the oil storage wall into two oil storage cavities is integrally arranged on the portion, on the inner side of the oil storage wall, of the top surface of the pump body, the two oil storage cavities communicate with the pump cavity through the two oil inlet holes correspondingly, and a pressure relief channel communicating with the pump cavity and one oil storage cavity is formed in the partition wall. And a pressure relief valve is mounted in the pressure relief channel. The brake master cylinder improves use safety and is compact in structure.

Description

Technical Field

[0001] The utility model belongs to the technical field of brake systems and relates to a dual-circuit pressurized brake master cylinder. Background Art

[0002] The master brake cylinder is a one-way acting piston hydraulic cylinder used to convert the mechanical energy input by the pedal mechanism into hydraulic energy. The master brake cylinder is an important component of the braking system.

[0003] For example, Chinese patent publication CN105438155B discloses a hydraulic booster for automotive brakes, comprising a brake master cylinder (i.e., a master cylinder). The master cylinder includes a master cylinder valve body, a booster piston and a slave piston disposed within the valve chamber of the master cylinder valve body, a first spring assembly disposed between the slave piston and the inner wall of the first end of the master cylinder valve body, and a second spring assembly disposed between the slave piston and the booster piston. The booster piston is connected to a push rod at one end facing away from the slave piston. An oil pot is mounted on the master cylinder valve body, with two connecting posts disposed at the bottom of the pot. The master cylinder valve body is provided with two connecting grooves, each of which is inserted into the grooves and secured to the grooves by sealing rings. The oil pot supplies oil to the master cylinder valve body through oil holes in the connecting posts. Because the connecting posts are located at the bottom of the pot, a leak between the connecting posts and the grooves can easily drain the oil from the pot under the action of gravity. This can cause the master cylinder to malfunction, leading to brake failure and safety issues.

[0004] In order to improve the sealing effect of the connection between the oil tank and the master cylinder valve body, and to improve the safety of the use of the brake master cylinder, the usual practice is to increase the number of sealing rings between the connecting column and the connecting groove. However, this requires extending the length of the connecting column, and the corresponding connecting groove height needs to be adaptively increased, resulting in an increase in the height of the brake master cylinder, which is prone to installation interference when assembled on the vehicle. Utility Model Content

[0005] The purpose of the utility model is to address the above-mentioned problems existing in the prior art and to propose a dual-circuit booster brake master cylinder, the technical problem to be solved is how to improve the safety of the use of the brake master cylinder.

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

[0007] A dual-circuit booster brake master pump comprises a pump body having a pump chamber, a piston assembly being arranged in the pump chamber, and two oil inlet holes being provided on the top wall of the pump chamber. The pump body is characterized in that a protruding oil storage wall is integrally provided on the top surface of the pump body, and a partition wall is integrally provided on the top surface of the pump body on the inner side of the oil storage wall, which is located between the two oil inlet holes and divides the inner chamber of the oil storage wall into two oil storage chambers. The two oil storage chambers are connected to the pump chamber through the two oil inlet holes respectively, and a pressure relief channel connecting the pump chamber and one of the oil storage chambers is provided on the partition wall, and a pressure relief valve is installed in the pressure relief channel.

[0008] During braking, the piston assembly slides forward under pressure, pressurizing the oil in the pump chamber and transferring it to the brake, thereby applying the brake. During the braking process, oil can be replenished into the pump chamber through the oil inlet. Because the oil reservoir is integrally mounted on the top surface of the pump body, leak points formed during separate connections are avoided, reducing the possibility of hydraulic oil leaks and improving safety. The partition wall divides the inner chamber of the oil reservoir into two oil chambers, each connected to the pump chamber via two oil inlet holes. This allows the other chamber to continue to supply hydraulic oil even if one chamber leaks, preventing complete brake failure and improving safety. Furthermore, the partition wall is integrally mounted on the pump body, leaving the bottoms of the two chambers disconnected. This ensures that even if one chamber leaks, the other chamber can still provide hydraulic oil.

[0009] When the oil pressure in the pump chamber is too high, the pressure relief valve opens, allowing the oil in the pump chamber to return to the reservoir through the pressure relief channel. This prevents the oil in the pump chamber from being released elsewhere, which would cause the oil in the reservoir to decrease continuously and affect braking, thereby improving safety. The integral partition wall on the top surface of the pump body places the pressure relief valve close to the pump chamber, allowing for rapid pressure relief and oil return to the reservoir. This reduces the risk of braking failures caused by delayed pressure relief and oil return. The single partition wall provides both isolation and pressure relief, improving safety while also making the brake pump compact.

[0010] In addition, the oil reservoir and partition wall are integrated into the pump body, reducing the joint height when the two components are connected. This reduces the overall height of the brake master cylinder and facilitates its installation. Furthermore, the pressure relief valve is located within the partition wall, eliminating the need for external space within the brake master cylinder. This makes the brake master cylinder compact and easy to assemble on the vehicle.

[0011] In the above-mentioned dual-circuit booster brake master cylinder, a through hole communicating with the two oil storage chambers is opened on the partition wall, and the lower side wall of the through hole is higher than the bottom end of the partition wall.

[0012] When the master brake cylinder is operating normally, the oil in the two reservoirs can flow through the through-hole. This prevents oil from entering only one reservoir when the pump chamber is depressurized, leaving the other reservoir depleted, thereby improving safety. The lower wall of the through-hole is higher than the bottom of the dividing wall, preventing the oil in one reservoir from leaking out of the other reservoir through the through-hole if one leaks, thus improving safety.

[0013] In the dual-circuit booster brake master cylinder described above, the partition wall has a mounting portion on one side of the through hole that protrudes toward one of the oil reservoirs, and the outlet of the pressure relief passage is located on the side of the mounting portion that faces the through hole. This allows the oil released into one of the oil reservoirs to quickly flow into the other, maintaining a balanced flow between the two reservoirs.

[0014] In the aforementioned dual-circuit booster brake master cylinder, the pressure relief valve includes a cylindrical valve core, and the pressure relief passage includes a cylindrical valve hole horizontally disposed on a mounting portion. The valve core is slidably inserted into the valve hole, and the valve hole is perpendicular to the sliding direction of the piston assembly. This reduces the effect of gravity on the valve core, making the valve core more responsive during pressure relief and improving user safety. It also facilitates valve hole machining and valve core installation, and makes the brake master cylinder structure more compact.

[0015] In the above-mentioned dual-path boost brake master cylinder, the pump chamber is a cylindrical hole, the chamber wall of the pump chamber has a step shape with the aperture decreasing from back to front, and the inlet of the pressure relief channel is located on the step surface of the step shape.

[0016] During braking, the piston assembly slides forward in the pump chamber. The cross-sectional area of ​​the pump chamber at the stepped portion decreases along the sliding direction of the piston assembly. During braking, the piston assembly slides forward in the pump chamber, increasing the oil pressure at the stepped portion. Once the pressure relief valve opens, pressure is released through the pressure relief passage. This prevents excessive oil pressure at the stepped portion from preventing the piston assembly from sliding and causing braking failure, thereby improving safety.

[0017] In the dual-path booster brake master cylinder, the pressure relief channel further includes an oblique straight hole located between the valve hole and the pressure relief channel inlet, the oblique straight hole being arranged obliquely upward toward the valve hole. The oblique straight hole can shorten the pressure relief path and achieve rapid pressure relief.

[0018] In the dual-circuit booster brake master cylinder, the top of the oil reservoir enclosure is covered with a top cover and a diaphragm, which are fixed to the top of the partition wall by bolts. The partition wall also serves to fix the top cover, making the brake master cylinder structure compact.

[0019] In the above-mentioned dual-way booster brake master cylinder, the piston assembly includes a master piston and a slave piston arranged in sequence from back to front, a first spring is arranged between the master piston and the slave piston, a second spring is arranged between the front end of the slave piston and the front end wall of the pump chamber, and a first leather cup that can prevent oil from flowing from front to back, a second leather cup and a third leather cup that can both allow oil to flow in one direction from back to front are fixed in sequence from back to front on the outer side surface of the master piston, a fourth leather cup that can prevent oil from flowing from back to front and a fifth leather cup that can allow oil to flow in one direction from back to front are fixed in sequence from back to front on the outer side surface of the slave piston, one of the oil inlet holes is located between the first leather cup and the second leather cup, the other oil inlet hole is located between the fourth leather cup and the fifth leather cup, the step surface is located between the second leather cup and the third leather cup, a first oil outlet hole is provided on the cavity wall surface of the pump chamber between the third leather cup and the fourth leather cup, and a second oil outlet hole is provided on the cavity wall surface of the pump chamber in front of the fifth leather cup.

[0020] In the pump chamber, the first oil inlet chamber is located between the first and second cups, the oil replenishment chamber is located between the second and third cups, the first brake chamber is located between the third and fourth cups, the second oil inlet chamber is located between the fourth and fifth cups, and the second brake chamber is located in front of the fifth cup. The inlet of the pressure relief passage is connected to the oil replenishment chamber, and the two oil inlet holes are connected to the first and second oil inlet chambers, respectively. The first and second oil outlet holes are connected to the first and second brake chambers, respectively. During braking, the piston assembly slides forward, compressing the first and second springs, and the first and second brake chambers. The pressurized oil flows out of the first and second oil outlet holes, causing braking. Simultaneously, the oil replenishment chamber is compressed, and the oil in the oil replenishment chamber enters the first brake chamber through the gap between the third cup and the wall of the pump chamber. When the brakes are released, the piston assembly slides backward under the action of the first and second springs, increasing the volume of the first and second brake chambers. Oil enters the first and second oil inlet chambers through the two oil inlet holes, and the oil in the first oil inlet chamber then flows into the oil replenishment chamber and the first brake chamber in sequence, while the oil in the second oil inlet chamber flows into the second brake chamber. During the braking process, if the oil pressure in the replenishment chamber is too high, the pressure relief valve opens, and the oil in the replenishment chamber flows into the oil storage chamber through the pressure relief channel, relieving the pressure in the replenishment chamber and preventing the piston assembly from being too rigid, i.e., too much resistance, and unable to push, resulting in abnormal braking.

[0021] In the above-mentioned dual-path boost brake master cylinder, a sealing gasket is fixed to one end of the valve core, and a sealing spring is connected to the valve core. Under the action of the sealing spring, the sealing gasket rests on the wall surface of the valve hole to block the pressure relief channel. A first sealing ring is provided between the outer side surface of the middle part of the valve core and the wall surface of the valve hole, and a protruding convex ring is provided on the outer side surface of the other end of the valve core. A second sealing ring is provided between the convex ring and the wall surface of the valve hole. A bypass hole connecting the valve hole and the first oil outlet is also provided on the mounting portion, and the connection between the bypass hole and the valve hole is located between the first sealing ring and the convex ring.

[0022] A sensing chamber is formed in the valve bore between the first sealing ring and the raised ring. This chamber communicates with the first brake chamber via a bypass hole and a first oil outlet hole. During braking, when the oil pressure in the oil-feeding chamber and the first brake chamber is normal, the sealing washer of the valve core, acting under the action of the sealing spring, presses against the wall of the valve bore, blocking the pressure relief passage. When the oil pressure in the oil-feeding chamber is too high, the first brake chamber and the oil-feeding chamber are in one-way communication via the third leather cup. The oil pressure in the first brake chamber also becomes excessively high, even slightly higher than that in the oil-feeding chamber. At this point, the oil pressure in the sensing chamber increases and acts on the raised ring, causing the valve core to move toward the other end, overcoming the force of the sealing spring. The sealing washer disengages from the wall of the valve bore, opening the pressure relief passage. Oil in the oil-feeding chamber flows through the pressure relief passage to the oil reservoir chamber. When the oil pressure in the oil-feeding chamber and the first brake chamber returns to normal, the sealing spring pushes the valve core, causing the sealing washer to re-block the pressure relief passage. Connecting the sensing chamber with the first brake chamber makes the pressure relief valve more responsive and achieves rapid pressure relief.

[0023] In the dual-circuit booster brake master cylinder, the first oil outlet is parallel to the valve core and connected to the upper side of the pump chamber, close to the mounting portion. This reduces the oil pressure transmission path, allowing the sensing chamber to quickly sense changes in the oil pressure in the first brake chamber, thereby quickly releasing pressure.

[0024] In the aforementioned dual-circuit booster brake master cylinder, a sealing plug is fixed to the valve hole, opposite the other end of the valve core. A socket is formed on the end surface of the other end of the valve core, and the spring is inserted into the socket and abuts against the sealing plug. The spring is installed within the valve core, making the valve core compact. The spring is also positioned within the valve core by the wall of the socket, ensuring stable operation.

[0025] In the dual-circuit booster brake master cylinder, a balancing hole is provided on the outer surface of the valve core, located between the sealing washer and the first sealing ring. The balancing hole is connected to the jack. This allows the jack to communicate with the oil replenishment chamber, preventing the jack from being sealed and affecting the pressure relief response of the valve core.

[0026] Compared with the prior art, the utility model has the following advantages:

[0027] An oil storage wall and a partition wall are integrally provided on the pump body. The partition wall not only divides the inner chamber of the oil storage wall into two oil storage chambers, but also a pressure relief channel connecting the pump chamber and the oil storage chamber is provided in the partition wall. A pressure relief valve is installed in the pressure relief channel, which improves the safety of the use of the master brake cylinder and makes the structure of the master brake cylinder compact. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a cross-sectional view of the first embodiment of the brake master cylinder (the pressure relief valve is hidden).

[0029] Figure 2 yes Figure 1 Cross-sectional view along the AA direction (piston assembly, top cover and sealing cap hidden).

[0030] Figure 3 This is a top view of the first embodiment of the brake master cylinder (the top cover and the sealing cap are partially cut away and the large plug and two small plugs are hidden).

[0031] In the figure, 1, main body; 1a, pump body; 1a1, pump chamber; 1a2, step surface; 1a3, oil inlet hole; 1a4, first oil outlet hole; 1a5, second oil outlet hole; 1a6, start hole; 1b, oil storage wall; 1b1, oil storage chamber; 1c, partition wall; 1c1, mounting portion; 1c2, bump; 1c3, through hole; 1c4, bypass hole; 1d, pressure relief channel; 1d1, inlet; 1d2, process hole; 1d3, oblique straight hole; 1d4, valve hole; 1d5, outlet; 2, top cover; 3, piston assembly; 3a, main piston; 3a1, first leather cup; 3a2, Second leather cup; 3a3, third leather cup; 3b, driven piston; 3b1, fourth leather cup; 3b2, fifth leather cup; 3c, first spring; 3d, second spring; 4, pressure relief valve; 4a, valve core; 4a1, convex ring; 4a2, socket; 4a3, balancing hole; 4b, sealing gasket; 4c, first sealing ring; 4d, second sealing ring; 4e, sealing spring; 5, sealing plug; 6, small plug; 7, large plug; 8, diaphragm; 9, bolt; PA, first oil inlet chamber; PB, oil replenishing chamber; PC, first brake chamber; PD, second oil inlet chamber; PE, second brake chamber. DETAILED DESCRIPTION

[0032] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0033] Example 1

[0034] like Figure 1As shown, a dual-path booster brake master cylinder includes a main body 1 and a top cover 2. The main body 1 is cast in one piece from a metal material, such as steel or aluminum alloy. The main body 1 includes a tubular pump body 1a and an oil storage wall 1b and a partition wall 1c that are integrally protruded and arranged on the top surface of the pump body 1a. The pump chamber 1a1 of the pump body 1a is cylindrical and arranged horizontally. A piston assembly 3 is arranged in the pump chamber 1a1 of the pump body 1a, and the piston assembly 3 can slide back and forth in the pump chamber 1a1. The sliding direction of the piston assembly 3 during braking is forward. The front end of the pump chamber 1a1 in the pump body 1a is closed, and the rear end of the pump chamber 1a1 of the pump body 1a is open. The outer side surface of the rear end of the pump body 1a is provided with a protruding connecting disk. Two oil inlet holes 1a3 are provided on the top wall of the pump chamber 1a1. The partition wall 1c is located between the two oil inlet holes 1a3 and divides the inner chamber of the oil storage wall 1b into two oil storage chambers 1b1. The two oil storage chambers 1b1 are connected to the pump chamber 1a1 through the two oil inlet holes 1a3 respectively.

[0035] like Figure 1 As shown, the wall surface of the pump chamber 1a1 has a stepped shape with a decreasing aperture from back to front. The piston assembly 3 includes a primary piston 3a and a secondary piston 3b, arranged sequentially from back to front. A first spring 3c is disposed between the primary and secondary pistons 3a and 3b, and a second spring 3d is disposed between the front end of the secondary piston 3b and the front end wall of the pump chamber 1a1. Affixed to the outer surface of the primary piston 3a, from back to front, are a first leather cup 3a1, which prevents oil from flowing from front to back; a second leather cup 3a2; and a third leather cup 3a3, both of which allow oil to flow unidirectionally from back to front. Affixed to the outer surface of the secondary piston 3b, from back to front, are a fourth leather cup 3b1, which prevents oil from flowing from back to front; and a fifth leather cup 3b2, which allows oil to flow unidirectionally from back to front. One of the oil inlet holes 1a3 is located between the first leather cup 3a1 and the second leather cup 3a2, and the other oil inlet hole 1a3 is located between the fourth leather cup 3b1 and the fifth leather cup 3b2. The step surface 1a2 of the step-shaped part is located between the second leather cup 3a2 and the third leather cup 3a3. A first oil outlet hole 1a4 is provided on the wall surface of the pump chamber 1a1 between the third leather cup 3a3 and the fourth leather cup 3b1, and a second oil outlet hole 1a5 is provided on the wall surface of the pump chamber 1a1 in front of the fifth leather cup 3b2. A starting hole 1a6 is also provided on the top wall of the pump chamber 1a1, which is located in front of the two oil inlet holes 1a3. The starting hole 1a6 connects the oil storage chamber 1b1 and the pump chamber 1a1. When the piston assembly 3 is reset, as shown in FIG. Figure 1 As shown, the first leather cup 3a1 and the fifth leather cup 3b2 are respectively located between the corresponding starting hole 1a6 and the oil inlet hole 1a3. When the brake is activated, the starting hole 1a6 and the oil inlet hole 1a3 maintain hydraulic balance between the front and rear sides of the first leather cup 3a1 and the fifth leather cup 3b2, preventing excessive hardness or excessive resistance during brake activation, so that the brake activation proceeds smoothly.

[0036] like Figure 1As shown, in the pump chamber 1a1, the first oil inlet chamber PA is located between the first and second cups 3a1 and 3a2, the oil replenishment chamber PB is located between the second and third cups 3a2 and 3a3, the first brake chamber PC is located between the third and fourth cups 3a3 and 3b1, the second oil inlet chamber PD is located between the fourth and fifth cups 3b1 and 3b2, and the second brake chamber PE is located in front of the fifth cup 3b2. The two oil inlet holes 1a3 communicate with the first and second oil inlet chambers PA and PD, respectively. The first and second oil outlet holes 1a4 and 1a5 communicate with the first and second brake chambers PC and PE, respectively. During braking, the piston assembly 3 slides forward, compressing the first and second springs 3c and 3d, and the first and second brake chambers PC and PE. This increases the pressure of the oil, which flows out of the first and second oil outlets 1a4 and 1a5 and into the brake, applying the applied force. Simultaneously, the oil replenishment chamber PB is compressed, and the oil in the replenishment chamber PB flows through the gap between the third cup 3a3 and the wall of the pump chamber 1a1 into the first brake chamber PC. During brake release, the piston assembly 3 slides backward under the action of the first and second springs 3c and 3d, returning the volume of the first and second brake chambers PC and PE to a higher level. Oil then flows through the two oil inlet holes 1a3 into the first and second oil inlet chambers PA and PD, respectively. The oil in the first oil inlet chamber PA then flows into the replenishment chamber PB and the first brake chamber PC, and the oil in the second oil inlet chamber PD flows into the second brake chamber PE. Brakes are typically also equipped with a return line to allow excess oil to return to the reservoir chamber 1b1 when the brake is released.

[0037] like Figure 1 and Figure 2As shown, the partition wall 1c defines a pressure relief passage 1d connecting the pump chamber 1a1 and one of the oil reservoir chambers 1b1. A pressure relief valve 4 is installed within the pressure relief passage 1d. A through hole 1c3 is defined in the partition wall 1c, connecting the two oil reservoir chambers 1b1. The lower wall of the through hole 1c3 is higher than the bottom end of the partition wall 1c. A mounting portion 1c1 protrudes toward one of the oil reservoir chambers 1b1 on one side of the through hole 1c3. The outlet 1d5 of the pressure relief passage 1d is located on the side of the mounting portion 1c1 facing the through hole 1c3. The inlet 1d1 of the pressure relief passage 1d is located on the stepped surface 1a2 of the pump chamber 1a1. The pressure relief valve 4 includes a cylindrical valve core 4a. The pressure relief passage 1d includes a cylindrical valve hole 1d4 horizontally disposed on the mounting portion 1c1. The valve core 4a is inserted into the valve hole 1d4 and can slide left and right. The valve hole 1d4 is perpendicular to the sliding direction of the piston assembly 3. The inner end of the valve hole 1d4 is connected to the outlet 1d5 of the pressure relief channel 1d. The outer end of the valve hole 1d4 is located on the outer surface of the oil storage wall 1b. A sealing plug 5 is sealed and fixed to the outer end of the valve hole 1d4. The pressure relief channel 1d also includes an oblique straight hole 1d3 located between the valve hole 1d4 and the inlet 1d1 of the pressure relief channel 1d. The upper end of the oblique straight hole 1d3 is located on the upper surface of the mounting portion 1c1, and a small plug 6 is sealed and fixed to the upper end of the oblique straight hole 1d3. The partition wall 1c also has a protrusion 1c2 protruding into the other oil storage chamber 1b1. The upper surface of the protrusion 1c2 is provided with a process hole 1d2 connecting the oblique straight hole 1d3 and the inlet 1d1 of the pressure relief channel 1d. A large plug 7 is sealed and fixed to the upper end of the process hole 1d2. The bottom surface of the process hole 1d2 also has a small activation hole 1a6 to balance the front and rear hydraulic pressures of the third leather cup 3a3 during brake activation, preventing excessive braking.

[0038] like Figure 2As shown, a sealing gasket 4b is fixed to the inner end of the valve core 4a. A sealing spring 4e is connected to the valve core 4a. Under the action of the sealing spring 4e, the sealing gasket 4b abuts against the wall of the valve hole 1d4, blocking the pressure relief channel 1d. A socket 4a2 is formed on the outer end of the valve core 4a. The spring is inserted into the socket 4a2 and abuts against the plug. A first sealing ring 4c is positioned between the outer side of the middle portion of the valve core 4a and the wall of the valve hole 1d4. A protruding collar 4a1 is provided on the outer side of the outer end of the valve core 4a. A second sealing ring 4d is positioned between the collar 4a1 and the wall of the valve hole 1d4. Both the first sealing ring 4c and the second sealing ring 4d are fixed to the valve core 4a. The connection between the oblique straight hole 1d3 and the valve hole 1d4 is located between the sealing gasket 4b and the first sealing ring 4c. The oblique straight hole 1d3 is arranged obliquely from bottom to top toward the valve hole 1d4. A balancing hole 4a3 is provided on the outer surface of the valve core 4a between the sealing gasket 4b and the first sealing ring 4c. The balancing hole 4a3 is connected to the insertion hole 4a2. A bypass hole 1c4 is also vertically provided on the mounting portion 1c1 of the partition wall 1c, connecting the valve hole 1d4 and the first oil outlet hole 1a4. The connection point between the bypass hole 1c4 and the valve hole 1d4 is located between the first sealing ring 4c and the convex ring 4a1. Figure 3 As shown, the upper end of bypass hole 1c4 is located on the upper surface of mounting portion 1c1, and a small plug 6 is sealed and fixed to the upper end of bypass hole 1c4. The lower end of bypass hole 1c4 is located on the wall surface of first oil outlet hole 1a4. First oil outlet hole 1a4 is arranged parallel to valve hole 1d4, connected to the upper side of pump chamber 1a1 and close to mounting portion 1c1.

[0039] like Figure 1 and Figure 2As shown, a sensing chamber is formed in the valve hole 1d4 between the first sealing ring 4c and the convex ring 4a1, and a valve control chamber is formed between the first sealing ring 4c and the sealing gasket 4b. The sensing chamber is connected to the first brake chamber PC through the bypass hole 1c4 and the first oil outlet hole 1a4, and the valve control chamber is connected to the oil replenishing chamber PB through the oblique straight hole 1d3 and the process hole 1d2. During braking, when the oil pressures in the oil replenishing chamber PB and the first brake chamber PC are normal, the sealing gasket 4b of the valve core 4a rests on the wall surface of the valve hole 1d4 under the action of the sealing spring 4e to block the pressure relief channel 1d. When the oil pressure in the oil replenishing chamber PB is too high, the first brake chamber PC and the oil replenishing chamber PB are connected in one direction through the third leather cup 3a3, and the oil pressure in the first brake chamber PC will also be too high, even slightly higher than that in the oil replenishing chamber PB. At this time, the oil pressure in the sensing chamber increases and acts on the convex ring 4a1, causing the valve core 4a to overcome the force of the sealing spring 4e and move toward the outward end. The sealing gasket 4b disengages from the wall surface of the valve hole 1d4 to open the outlet 1d5 of the pressure relief channel 1d, and the oil in the oil replenishing chamber PB flows into the oil storage chamber 1b1 through the pressure relief channel 1d. When the oil pressures in the oil replenishing chamber PB and the first brake chamber PC are restored, the sealing spring 4e pushes the valve core 4a to cause the sealing gasket 4b to block the pressure relief channel 1d again.

[0040] like Figure 1 and Figure 3 As shown, the top cover 2 is covered on the top of the oil storage wall 1b, and a diaphragm 8 is provided between the top cover 2 and the top of the oil storage wall 1b. The top cover 2 and the diaphragm 8 are fixedly connected to the top of the partition wall 1c by bolts 9.

[0041] Example 2

[0042] The valve hole 1d4 is cylindrical and vertically arranged on the mounting portion 1c1, the insertion hole 4a2 is arranged on the upper surface of the valve core 4a, and the sealing plug 5 is fixed in the upper end of the valve hole 1d4 and located above the valve core 4a. The other structures are basically the same as those in the first embodiment.

[0043] Example 3

[0044] The structure of the pressure relief valve 4 differs from that of Example 1, but its other structures are essentially the same as those of Example 1. The valve hole 1d4 is cylindrical and vertically mounted on the mounting portion 1c1. The oblique straight hole 1d3 is located below and communicates with the valve hole 1d4. The diameter of the valve hole 1d4 is larger than that of the oblique straight hole 1d3. The outlet 1d5 of the pressure relief passage 1d is located at the junction of the valve hole 1d4 and the oblique straight hole 1d3. The valve core 4a is cylindrical and inserted into the valve hole 1d4. A sealing plug 5 is fixed to the top end of the valve hole 1d4. A sealing gasket 4b is fixed to the bottom surface of the valve core 4a. A sealing spring 4e is connected between the top end of the valve core 4a and the sealing plug 5. Under the action of the sealing spring 4e, the sealing gasket 4b abuts against the wall connecting the valve hole 1d4 and the oblique straight hole 1d3, blocking the pressure relief passage 1d. When the oil pressure in oil charge chamber PB is too high, the oil in oblique bore 1d3 pushes valve core 4a open, allowing the oil to flow into oil reservoir chamber 1b1 through outlet 1d5 of pressure relief passage 1d. When the oil pressure in oil charge chamber PB recovers, sealing spring 4e pushes valve core 4a, causing sealing gasket 4b to re-block pressure relief passage 1d.

[0045] 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 defined by the appended claims.

Claims

1. A dual-circuit booster brake master cylinder, comprising a pump body (1a) having a pump chamber (1a1), a piston assembly (3) being disposed in the pump chamber (1a1), two oil inlet holes (1a3) being provided on a top wall of the pump chamber (1a1), characterized in that: A protruding oil storage wall (1b) is integrally provided on the top surface of the pump body (1a). A partition wall (1c) is integrally provided on the top surface of the pump body (1a) on the inner side of the oil storage wall (1b), which is located between two oil inlet holes (1a3) and divides the inner chamber of the oil storage wall (1b) into two oil storage chambers (1b1). The two oil storage chambers (1b1) are connected to the pump chamber (1a1) through the two oil inlet holes (1a3), respectively. A pressure relief channel (1d) is provided on the partition wall (1c) and is connected to the pump chamber (1a1) and one of the oil storage chambers (1b1). A pressure relief valve (4) is installed in the pressure relief channel (1d).

2. The dual-circuit booster brake master cylinder according to claim 1, characterized in that: A through hole (1c3) communicating with the two oil storage chambers (1b1) is provided on the partition wall (1c), and a lower hole wall of the through hole (1c3) is higher than the bottom end of the partition wall (1c).

3. The dual-circuit booster brake master cylinder according to claim 2, characterized in that: The partition wall (1c) has a mounting portion (1c1) on one side of the through hole (1c3) that protrudes toward one of the oil storage chambers (1b1), and the outlet (1d5) of the pressure relief channel (1d) is arranged on the side of the mounting portion (1c1) facing the through hole (1c3).

4. The dual-circuit booster brake master cylinder according to claim 3, characterized in that: The pressure relief valve (4) includes a columnar valve core (4a), the pressure relief channel (1d) includes a columnar valve hole (1d4) horizontally arranged on the mounting portion (1c1), the valve core (4a) is inserted into the valve hole (1d4) and is slidable, and the valve hole (1d4) is perpendicular to the sliding direction of the piston assembly (3).

5. The dual-circuit booster brake master cylinder according to claim 4, characterized in that: The pump cavity (1a1) is a cylindrical hole, and the cavity wall of the pump cavity (1a1) has a stepped shape with a smaller aperture from the back to the front, and the inlet (1d1) of the pressure relief channel (1d) is located on the stepped surface (1a2) of the stepped shape.

6. The dual-circuit booster brake master cylinder according to claim 4 or 5, characterized in that: The pressure relief channel (1d) further comprises an oblique straight hole (1d3) located between the valve hole (1d4) and the inlet (1d1) of the pressure relief channel (1d), wherein the oblique straight hole (1d3) is arranged obliquely from bottom to top toward the valve hole (1d4).

7. The dual-circuit booster brake master cylinder according to any one of claims 1 to 5, characterized in that: The top of the oil storage enclosure (1b) is covered with a top cover (2) and a diaphragm (8), and the top cover (2) and the diaphragm (8) are fixedly connected to the top of the partition wall (1c) by bolts (9).

8. The dual-circuit booster brake master cylinder according to claim 5, characterized in that: The piston assembly (3) comprises a main piston (3a) and a slave piston (3b) arranged in sequence from back to front, a first spring (3c) being provided between the main piston (3a) and the slave piston (3b), a second spring (3d) being provided between the front end of the slave piston (3b) and the front end wall of the pump chamber (1a1), a first leather cup (3a1) capable of preventing oil from flowing from front to back, a second leather cup (3a2) and a third leather cup (3a3) both capable of allowing oil to flow in one direction from back to front being fixed on the outer surface of the main piston (3a), and a fourth leather cup (3a4) capable of preventing oil from flowing from back to front being fixed on the outer surface of the slave piston (3b). A leather cup (3b1) and a fifth leather cup (3b2) capable of allowing oil to flow in one direction from back to front, wherein one oil inlet hole (1a3) is located between the first leather cup (3a1) and the second leather cup (3a2), the other oil inlet hole (1a3) is located between the fourth leather cup (3b1) and the fifth leather cup (3b2), the step surface (1a2) is located between the second leather cup (3a2) and the third leather cup (3a3), a first oil outlet hole (1a4) is provided on the wall surface of the pump chamber (1a1) between the third leather cup (3a3) and the fourth leather cup (3b1), and a second oil outlet hole (1a5) is provided on the wall surface of the pump chamber (1a1) in front of the fifth leather cup (3b2).

9. The dual-circuit booster brake master cylinder according to claim 8, characterized in that: A sealing gasket (4b) is fixed to one end of the valve core (4a), and a sealing spring (4e) is connected to the valve core (4a). Under the action of the sealing spring (4e), the sealing gasket (4b) abuts against the hole wall surface of the valve hole (1d4) to block the pressure relief channel (1d). A first sealing ring (4c) is provided between the outer side surface of the middle part of the valve core (4a) and the hole wall surface of the valve hole (1d4). A protruding convex ring (4a1) is provided on the outer side surface of the other end of the valve core (4a), and a second sealing ring (4d) is provided between the convex ring (4a1) and the hole wall surface of the valve hole (1d4). A bypass hole (1c4) connecting the valve hole (1d4) and the first oil outlet hole (1a4) is also provided on the mounting portion (1c1), and the connection point between the bypass hole (1c4) and the valve hole (1d4) is located between the first sealing ring (4c) and the convex ring (4a1).

10. The dual-circuit booster brake master cylinder according to claim 9, characterized in that: The first oil outlet hole (1a4) is arranged parallel to the valve core (4a), and the first oil outlet hole (1a4) is connected to the upper side of the pump chamber (1a1) and is close to the mounting portion (1c1).

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