CN111301380A

CN111301380A - Hydraulic brake system

Info

Publication number: CN111301380A
Application number: CN202010269150.8A
Authority: CN
Inventors: 杜立新; 殷古鹏; 陶喆; 范鹏; 刘倩; 于鑫; 孙来九; 曾俊林
Original assignee: Nasn Automotive Electronics Co Ltd
Current assignee: Nasn Automotive Electronics Co Ltd
Priority date: 2020-04-08
Filing date: 2020-04-08
Publication date: 2020-06-19
Anticipated expiration: 2040-04-08
Also published as: CN111301380B

Abstract

The invention discloses a hydraulic brake system, belongs to the technical field of automobile brake systems, and aims to solve the problem that the conventional brake system can form good damping feeling and hysteresis feeling. The hydraulic brake system of the present invention comprises: a push rod connected to the master cylinder piston; a liquid storage tank for storing a braking medium; one end of the push rod is connected to the pedal assembly, and the other end of the push rod faces the push ejector rod; the push rod piston is sleeved on the periphery and the end part of the push rod and can move under the thrust of the push rod or the thrust of a braking medium; the flange plate is sleeved on the periphery of the push rod piston, and a push rod piston cavity is formed between the flange plate and the push rod piston; a first channel, a first load cavity, a second channel and a second load cavity are arranged in the flange plate; and the electromagnetic valve is arranged on a first pipeline of the liquid storage tank between the liquid storage tank and the first load cavity. The hydraulic brake system can form damping feeling and lagging feeling on the pedal assembly, is more comfortable to use and has no obvious footstep feeling.

Description

Hydraulic brake system

Technical Field

The invention relates to the technical field of automobile braking systems, in particular to a hydraulic braking system.

Background

The hydraulic brake system is an important component in motor vehicles such as automobiles, and a user brakes through a pedal and other structures.

Electronic brake products are mostly adopted in the existing motor vehicles, so that the feet of a user are prevented from being injured by reaction force generated by pure mechanical contact in a brake structure or the feet feel bad, and a pedal simulator is arranged in the electronic brake products. The existing pedal simulator is usually a pure spring structure or a structure formed by matching a spring and rubber, and the elasticity of the spring is utilized to generate damping feeling and lagging feeling on the foot of a user.

No matter the structure is a pure spring structure or a structure formed by matching a spring and rubber, the hardness of the load at the tail end cannot be accurately controlled, the feeling of pushing the foot is serious, and some products even have no damping feeling and hysteresis feeling, so that the feeling of the foot of a user is not good enough, and the requirement of the user is difficult to meet.

Disclosure of Invention

The invention aims to provide a hydraulic brake system with good damping feeling and hysteresis feeling.

In order to achieve the purpose, the invention adopts the following technical scheme:

a hydraulic brake system comprising: a push rod connected to the master cylinder piston; a liquid storage tank for storing a braking medium; one end of the push rod is connected to the pedal assembly, and the other end of the push rod faces the push ejector rod; the push rod piston is sleeved on the periphery and the end part of the push rod and can move under the thrust of the push rod or the thrust of the braking medium; the flange plate is sleeved on the periphery of the push rod piston, a push rod piston cavity is formed between the flange plate and the push rod piston, and the brake medium is filled in the push rod piston cavity; a first channel, a first load cavity, a second channel and a second load cavity are arranged in the flange plate, the first channel is arranged between the push rod piston cavity and the first load cavity, a load piston is arranged between the first load cavity and the second load cavity, and the second channel is arranged between the second load cavity and the liquid storage tank; and the electromagnetic valve is arranged on a first pipeline of the liquid storage tank between the liquid storage tank and the first load cavity.

Particularly, two sealing devices are sequentially arranged between the push rod piston and the flange at intervals, an oil return hole is formed in the flange and located between the first sealing device and the second sealing device, and the oil return hole is connected to the liquid storage tank through a second pipeline of the liquid storage tank.

In particular, the first sealing device and/or the second sealing device is a star-shaped sealing ring, a lip-shaped sealing ring, a Y-shaped sealing ring, a special-shaped sealing ring or an O-shaped sealing ring.

In particular, the hydraulic brake system further comprises a third sealing device, and the push rod piston cavity is located between the third sealing device and the first sealing device.

In particular, a compensation hole is provided in the plunger piston, which connects the oil return hole to the plunger piston cavity.

Particularly, a push rod elastic device is arranged on the periphery of the push rod piston; and/or a load elastic device is arranged on the load piston.

Particularly, a braking medium compensation channel is arranged on the first pipeline of the liquid storage tank, two ends of the braking medium compensation channel are respectively connected to two sides of the electromagnetic valve, and a compensation check valve is arranged on the braking medium compensation channel.

In particular, the solenoid valve is a normally open valve.

In particular, the flange is provided with an orifice, and throttle check valves are bridged across both ends of the orifice.

In particular, the hydraulic brake system further comprises a power assisting unit for supplying power to the solenoid valve.

The flange plate of the hydraulic brake system is internally provided with the first channel, the first load cavity, the second channel and the second load cavity, when the push rod piston is stressed to move, hydraulic pressure can push the load to move, and then damping feeling and hysteresis feeling are formed on the pedal assembly, so that the hydraulic brake system is more comfortable to use and has no obvious foot supporting feeling.

Drawings

FIG. 1 is a schematic structural diagram illustrating an electric power assisted state of a hydraulic braking system according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a hydraulic braking system in a no-power-up/power-down state according to an embodiment of the present invention.

In the figure:

1. a push rod; 2. a push rod elastic device; 3. a push rod piston; 4. a flange plate; 5. a booster unit; 6. an electromagnetic valve; 7. a compensating check valve; 8. a load piston; 9. a load spring device; 10. a liquid storage tank; 11. a master cylinder piston; 12. pushing the ejector rod; 13. a pedal assembly; 31. a pushrod piston cavity; 32. a compensation hole; 41. a first channel; 42. a second channel; 43. a first load chamber; 44. a second load chamber; 45. a first sealing device; 46. a second sealing device; 47. an oil return hole; 48. a third sealing device; 49. an orifice; 50. a throttle check valve; 101. a first pipeline of the liquid storage tank; 102. a second pipeline of the liquid storage tank.

Detailed Description

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

The present embodiment discloses a hydraulic brake system, as shown in fig. 1 and 2, the hydraulic brake system includes a push rod 12, a reservoir 10 for storing a brake medium, a push rod 1, a push rod piston 3, a flange 4, a solenoid valve 6, and a booster unit 5 for supplying power to the solenoid valve 6. Wherein, promote ejector pin 12 and be connected to master cylinder piston 11, push rod 1 one end is connected on footboard subassembly 13 and the other end is towards promoting ejector pin 12, and push rod piston 3 cover is established in the periphery and the tip of push rod 1 and can move under the thrust of push rod 1 or the thrust of brake media. The push rod piston 3 pushes the main cylinder piston 11 by pushing the push rod 12 through extrusion, so that the braking function is realized.

The flange plate 4 is sleeved on the periphery of the push rod piston 3, a push rod piston cavity 31 is formed between the flange plate 4 and the push rod piston 3, the brake medium is filled in the push rod piston cavity 31, and the brake medium is preferably hydraulic oil. A first passage 41, a first load chamber 43, a second passage 42 and a second load chamber 44 are arranged in the flange plate 4, the first passage 41 is arranged between the push rod piston chamber 31 and the first load chamber 43, a load piston 8 is arranged between the first load chamber 43 and the second load chamber 44, and the second passage 42 is arranged between the second load chamber 44 and the reservoir tank 10. The solenoid valve 6 is disposed on the first line 101 of the reservoir between the reservoir 10 and the first load chamber 43, the solenoid valve 6 preferably being a normally open valve; if the electromagnetic valve 6 is a normally closed valve, the normal use is not influenced, but the on-off rule is opposite to that of the normally open valve.

By utilizing the incompressibility and the fluidity of the hydraulic oil, the design of the first channel 41, the first load cavity 43, the second channel 42 and the second load cavity 44 ensures that the hydraulic oil flows when a user steps on the brake pedal to form pressure building/pressure relief, so that the damping feeling and the hysteresis feeling are realized on the brake pedal, the hardness degree of the load at the tail section is moderate, no obvious footstep feeling exists, the use is more comfortable, and the fatigue of the feet of the user can not be caused even after the long-time use.

In order to avoid insufficient hydraulic oil caused by leakage and the like, a braking medium compensation channel is arranged on the first pipeline 101 of the liquid storage tank, two ends of the braking medium compensation channel are respectively connected to two sides of the electromagnetic valve 6, and a compensation check valve 7 is arranged on the braking medium compensation channel. When the leakage occurs in the push rod piston cavity 31 or the first load cavity 43, the pressure of the push rod piston cavity 31 is smaller than the pressure at the end of the liquid storage tank 10, the compensation check valve 7 is started, and the oil liquid in the liquid storage tank 10 is timely supplemented into the first load cavity 43.

A push rod spring device 2 is provided on the outer periphery of the push rod piston 3, and a load spring device 9 is provided on the load piston 8. At least two sealing devices are sequentially arranged between the push rod piston 3 and the flange plate 4 at intervals, an oil return hole 47 is formed in the flange plate 4 and located between the first sealing device 45 and the second sealing device 46, and the oil return hole 47 is connected to the liquid storage tank 10 through a second pipeline 102 of the liquid storage tank; a compensation bore 32 is provided in the tappet piston 3. When the brake pedal is withdrawn, the push rod piston 3 moves outwards under the pushing of the push rod elastic device 2, when the push rod piston 3 retreats between the first sealing device 45 and the second sealing device 46, the compensation hole 32 connects the oil return hole 47 to the push rod piston cavity 31, so that the communication between the liquid storage tank 10 and the push rod piston cavity 31 is realized, hydraulic oil can directly enter the push rod piston cavity 31 through the second pipeline 102 of the liquid storage tank, the hydraulic oil does not need to flow through the second channel 42, the second load cavity 44, the first load cavity 43 and the first channel 41, and the damping sense and the hysteresis sense disappear.

To achieve a better seal, the first sealing device 45 and the second sealing device 46 may each be, but are not limited to, a star seal, a lip seal, a Y seal, a profile seal, or an O-ring.

On the basis of the structure, the hydraulic brake system further comprises a third sealing device 48, and the push rod piston cavity 31 is located between the third sealing device 48 and the first sealing device 45, so that the sealing performance of the whole device is further improved, and leakage or evaporation of hydraulic oil is reduced.

The working principle of the hydraulic brake system is as follows:

as shown in fig. 1, the power assisting unit 5 supplies power to the solenoid valve 6, and the solenoid valve 6 is closed, so that the first pipeline 101 of the liquid storage tank between the first load chamber 43 and the liquid storage tank 10 is in a closed state, no matter the pedal is stepped on or released, hydraulic oil cannot flow through the solenoid valve 6, and the power-on power assisting state is realized.

The user steps on the pedal assembly 13 to give a braking force F to the push rod 1, and the push rod 1 pushes the push rod piston 3 to move towards the push rod 12. The initial push rod elastic device 2 is compressed, and after the compensation hole 32 on the push rod piston 3 passes through the second sealing device 46, the oil return hole 47 is isolated from the push rod piston cavity 31, and pressure begins to build. The initial force developed at this time is provided by the pusher spring means 2.

When the push rod piston 3 pushes the push rod 12 to perform braking, the second sealing device 46 and the third sealing device 48 jointly maintain the sealing performance of the push rod piston cavity 31, hydraulic oil in the push rod piston cavity 31 is pushed by the push rod piston 3 to enter the first channel 41 and the first load cavity 43 in sequence, the hydraulic oil is incompressible, and the sealing ring arranged between the load piston 8 and the flange plate 4 ensures that the hydraulic oil cannot leak from the first load cavity 43 to the second load cavity 44, so that the hydraulic oil in the first load cavity 43 pushes the load piston 8 to move to the right, the load elastic device 9 (preferably elastic parts such as springs, disc springs and rubber) compresses, and the hydraulic oil in the second load cavity 44 enters the liquid storage tank 10 through the second channel 42. Through the deformation of a series of elastic devices, the friction between the sealing device and the push rod piston 3 and the flowing of hydraulic oil, damping feeling and hysteresis feeling are generated at the brake pedal, namely pedal feeling is obtained, and the foot feeling of a user is more comfortable.

The force value of the load elastic device 9 is adjustable, the force value curve of the load elastic device 9 is adjusted according to different requirements, different braking force pedal curves can be obtained, and different pedal feelings can be obtained.

When the user releases the pedal assembly 13, the force F on the push rod 1 is reduced, and the force acting on the load piston 8 is smaller than the force compressing the load spring 9, and the load spring 9 pushes the load piston 8 to move leftward. The hydraulic oil in the first load chamber 43 flows back to the rod piston chamber 31 via the first channel 41. When the push rod piston 3 is retracted between the first sealing device 45 and the second sealing device 46, the compensation hole 32 connects the oil return hole 47 to the push rod piston cavity 31, the hydraulic oil in the reservoir 10 directly enters the push rod piston cavity 31 through the reservoir second pipeline 102, and the load piston 8 no longer moves.

Preferably, an orifice 49 (having a cross-sectional area smaller than that of the first passage 41) is provided in the first passage 41 of the flange 4, and a throttle check valve 50 is bridged across both ends of the orifice 49, thereby regulating the flow rate of the hydraulic oil flowing through the first passage 41. Specifically, when the user steps on the pedal, the throttle check valve 50 is turned on, and the hydraulic oil in the first passage 41 can smoothly enter the first load chamber 43 through the throttle check valve 50; when the user steps on the pedal, the throttle check valve 50 is closed, and the hydraulic oil in the first load chamber 43 flows slowly from the throttle hole 49 into the first passage 41, so that a hysteresis feeling is created.

As shown in fig. 2, the booster unit 5 does not supply power to the solenoid valve 6, and the solenoid valve 6 is in an open state, so that the first pipeline 101 of the liquid storage tank between the first load chamber 43 and the liquid storage tank 10 is in an open state, which is a no-booster/power-off state.

The user steps on the pedal assembly 13 to give a braking force F to the push rod 1, and the push rod 1 pushes the push rod piston 3 to move towards the push rod 12. The initial push rod elastic device 2 is compressed, and after the compensation hole 32 on the push rod piston 3 passes through the second sealing device 46, the oil return hole 47 is isolated from the push rod piston cavity 31. The hydraulic oil in the push rod piston cavity 31 enters the liquid storage tank 10 after passing through the first channel 41, the first load cavity 43, the electromagnetic valve 6 and the first pipeline 101 of the liquid storage tank, at the moment, the force on the push rod 1 is not consumed on a simulated load, the push rod piston 3 can easily extrude and push the push rod 12, and the push rod 12 pushes the master cylinder piston 11, so that pressure building and braking are realized.

It should be noted that the foregoing is only a preferred embodiment of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A hydraulic brake system, comprising:

a push rod (12) connected to the master cylinder piston (11);

a reservoir (10) for storing a brake medium;

one end of the push rod (1) is connected to the pedal assembly (13), and the other end of the push rod faces the push ejector rod (12);

the push rod piston (3) is sleeved on the periphery and the end part of the push rod (1) and can move under the thrust of the push rod (1) or the thrust of the braking medium;

the flange plate (4) is sleeved on the periphery of the push rod piston (3), a push rod piston cavity (31) is formed between the flange plate (4) and the push rod piston (3), and the brake medium is filled in the push rod piston cavity (31); a first channel (41), a first load cavity (43), a second channel (42) and a second load cavity (44) are arranged in the flange plate (4), the first channel (41) is arranged between the push rod piston cavity (31) and the first load cavity (43), a load piston (8) is arranged between the first load cavity (43) and the second load cavity (44), and the second channel (42) is arranged between the second load cavity (44) and the liquid storage tank (10); and the number of the first and second groups,

and the electromagnetic valve (6) is arranged on a first pipeline (101) of the liquid storage tank between the liquid storage tank (10) and the first load cavity (43).

2. Hydraulic braking system according to claim 1, characterised in that at least two sealing means are provided in sequence at intervals between the push rod piston (3) and the flange (4), an oil return hole (47) being provided in the flange (4) between the first sealing means (45) and the second sealing means (46), the oil return hole (47) being connected to the reservoir (10) by a reservoir second line (102).

3. Hydraulic braking system according to claim 2, characterized in that the first sealing means (45) and/or the second sealing means (46) are star-shaped sealing rings, lip-shaped sealing rings, Y-shaped sealing rings, profiled sealing rings or O-rings.

4. The hydraulic braking system of claim 2, further comprising a third sealing means (48), the pushrod piston cavity (31) being located between the third sealing means (48) and the first sealing means (45).

5. Hydraulic braking system according to claim 2, characterized in that a compensation bore (32) is provided on the tappet piston (3), which compensation bore (32) connects the oil return bore (47) to the tappet piston chamber (31).

6. The hydraulic brake system according to any one of claims 1 to 5, characterized in that a push rod resilient means (2) is provided on the outer periphery of the push rod piston (3); and/or a load spring device (9) is arranged on the load piston (8).

7. The hydraulic brake system as claimed in any one of claims 1 to 5, wherein a brake medium compensation passage is provided on the reservoir tank first pipe (101), both ends of the brake medium compensation passage are respectively connected to both sides of the solenoid valve (6), and a compensation check valve (7) is provided on the brake medium compensation passage.

8. Hydraulic braking system according to any one of claims 1 to 5, characterized in that the solenoid valve (6) is a normally open valve.

9. The hydraulic brake system according to any one of claims 1 to 5, wherein an orifice (49) is provided in the flange plate (4), and a throttle check valve (50) is bridged across both ends of the orifice (49).

10. Hydraulic braking system according to any one of claims 1 to 5, characterized in that it further comprises a power-assisting unit (5) for powering the solenoid valve (6).