CN113386721A

CN113386721A - Brake booster for vehicle, vehicle and vehicle brake control method

Info

Publication number: CN113386721A
Application number: CN202010174570.8A
Authority: CN
Inventors: 崔晋
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2020-03-13
Filing date: 2020-03-13
Publication date: 2021-09-14

Abstract

The application provides a brake booster for a vehicle, a vehicle and a brake control method thereof. The brake booster includes: a first brake cylinder configured to receive a force from a brake pedal of a vehicle to compress hydraulic fluid within the first brake cylinder and provide a cushioning material area for cushioning the force from the brake pedal of the vehicle; the second brake cylinder is provided with two fluid spaces which are sealed with each other, the two fluid spaces are configured to be respectively connected with the first brake cylinder through fluid pipelines and are respectively communicated with or disconnected from the first brake cylinder in a controlled manner; the second brake cylinder is configured to receive a force from a driving member to compress hydraulic fluid within the second brake cylinder, wherein the force of the driving member is associated with a braking stroke of a brake pedal of the vehicle; wherein the brake booster is configured to transmit force from the brake pedal and/or the driving member to brake the wheel by compressing the hydraulic fluid. The brake booster according to the present application can achieve effective braking and improve pedal feel.

Description

Brake booster for vehicle, vehicle and vehicle brake control method

Technical Field

The present application relates to the field of vehicles, and more particularly, to a brake booster for a vehicle, and a brake control method thereof.

Background

The vehicle brake system is a key ring in the vehicle, which provides a sufficient guarantee for the safety of vehicle users, so the vehicle brake technology is focused on development. At present, a common technology is a hydraulic brake system, that is, after a user presses a brake pedal, the stroke of the brake pedal is directly transmitted to a brake cylinder to compress hydraulic fluid therein to transmit torque, and finally, the wheel is braked. With such techniques, a user may need to use a greater amount of force to effect braking. For improving user experience, a brake booster is further designed for the hydraulic brake system, the brake pedal stroke is obtained through a controller, and then the driving motor is controlled to compress hydraulic fluid, so that the purpose of braking is achieved. At this time, it is the controlled driving motor that actually performs the compression of the fluid to perform the braking, whereby the user's force can be greatly saved. However, it is difficult for such booster to provide proper pedal feel feedback to the customer during the application process, or to cause a sudden pedal drop problem, thereby making it difficult for the user to confirm whether the braking action is controlled by pressing the pedal by himself, and there is also a lack of user experience.

Disclosure of Invention

In view of the above, the present application provides a brake booster for a vehicle, a vehicle and a vehicle brake control method, which effectively solve or alleviate one or more of the above problems and other problems in the prior art.

To solve at least one of the above technical problems, according to an aspect of the present application, there is provided a brake booster for a vehicle, including: a first brake cylinder configured to receive a force from a brake pedal of a vehicle to compress hydraulic fluid therein and provide a cushioning material area for cushioning the force from the brake pedal of the vehicle; and a second brake cylinder having two fluid spaces sealed from each other, the two fluid spaces being configured to be connected to the first brake cylinder by fluid lines, respectively, and to be controllably connected to and disconnected from the first brake cylinder, respectively; the second brake cylinder is configured to receive a force from a driving member to compress hydraulic fluid within the second brake cylinder, wherein the force of the driving member is associated with a braking stroke of a brake pedal of the vehicle; wherein the brake booster is configured to transmit force from the brake pedal and/or the driving member to brake a wheel by compressing hydraulic fluid.

To solve at least one of the above technical problems, according to another aspect of the present application, there is provided a vehicle including: the brake booster as described previously; a brake pedal and booster control unit; wherein a brake pedal is connected to the first brake cylinder of the brake booster, the booster control unit controlling the force applied by the drive component to the second brake cylinder on the basis of the brake stroke of the brake pedal as previously described for the electric machine rotor.

In order to solve at least one of the above technical problems, according to still another aspect of the present application, there is provided a brake control method for a vehicle as described above, including: a first braking mode in which a brake pedal of the vehicle is forced to move, the booster control unit controlling a force applied to the second brake cylinder by the driving member based on a braking stroke of the brake pedal to compress hydraulic fluid to brake a wheel; and the cushioning material region cushions a force from a brake pedal of the vehicle; and a second braking mode in which the booster control unit controls a force applied by the drive component to the second brake cylinder based on an external request signal to compress hydraulic fluid to brake a wheel; wherein the external request signal is a braking request signal from a component other than the brake booster.

According to the technical scheme of the application, the two brake cylinders are arranged to provide selection of various brake modes, so that the boosting brake function can be realized under normal operation, and the user can directly realize treading brake under an abnormal state. For example, the first brake cylinder may be adapted to receive a force generated by a user depressing a brake pedal, and on the one hand, directly compress hydraulic fluid and provide braking based on the force, and on the other hand, may only sense a braking stroke caused by the user depressing the brake pedal, and simultaneously associate the braking stroke with the drive member, thereby controllably compressing hydraulic fluid in the second brake cylinder to provide assisted braking. At the moment, the buffer material area in the first brake cylinder can be used for simulating the real foot feeling of braking for a user, so that the foot feeling of the pedal of the user in various modes is not more different, the brake pedal is more suitable for operation and control, and the situation that the pedal is dropped due to sudden pressure change of hydraulic fluid is avoided. In addition, multiple braking modes of the brake booster can be completed without cooperation of an electronic stability system of the vehicle body, and the reliability is high.

Drawings

The present application will be more fully understood from the detailed description given below with reference to the accompanying drawings, in which like reference numerals refer to like elements in the figures. Wherein:

FIG. 1 is a schematic illustration of an embodiment of a vehicle in a first braking mode;

FIG. 2 is a schematic illustration of an embodiment of a vehicle in a second braking mode; and

FIG. 3 is a schematic view of an embodiment of a vehicle in a fourth braking mode.

Detailed Description

First, it should be noted that the brake booster for a vehicle, the composition, the operating principle, the features and the advantages of the vehicle and the vehicle brake control method according to the present application, etc. will be described below by way of example, but it should be understood that all the descriptions are given for illustration only and thus should not be construed as forming any limitation to the present application. In this document, the technical term "connected" and its derivatives cover that one component is directly connected to another component and/or indirectly connected to another component. And the use of the verb "to comprise" is herein intended to mean two or more than two, as opposed to "a" or "an".

Furthermore, to any single feature described or implicit in an embodiment or shown or implicit in the drawings, the present application still allows any combination or permutation to continue between the features (or their equivalents) without any technical impediment, thereby achieving more other embodiments of the present application that may not be directly mentioned herein.

Fig. 1 to 3 show the general structure and operation of an exemplary embodiment of a brake booster according to the present application in a vehicle in a schematic manner from the perspective of the components and the relative positional relationship. The technical solution of the present application will be described in detail below with reference to the above drawings.

The brake booster 100 shown in fig. 1 to 3 has been installed in the vehicle 200, so that the components of the vehicle 200, including the brake pedal 210 and the electronic body stabilizing system 220, are also shown in connection therewith. For example, the brake booster 100 applied in the present embodiment may also be applied to a vehicle 200 without the body electronic stabilizing system 220, so that braking is accomplished without the assistance of the body electronic stabilizing system 220.

Brake booster 100 generally includes first brake cylinder 110 and second brake cylinder 120 interconnected by at least two

fluid lines

131, 132 between which hydraulic fluid may be controllably flowed or interrupted. When applied in a vehicle, first brake cylinder 110 is connected to a brake pedal 210 of the vehicle and second brake cylinder 120 is connected to the wheel by at least two

fluid lines

141, 142 and optionally via a body electronic stability system 220, thereby forming a complete transmission path for a force applied to brake pedal 210 to brake the wheel.

Specifically, first brake cylinder 110 is configured to receive a force from brake pedal 210 of vehicle 200 to compress hydraulic fluid within first brake cylinder 110. Furthermore, a damping material region 113 is to be provided therein for damping forces from a brake pedal 210 of the vehicle 200. Second brake cylinder 120 should have two

fluid spaces

120a, 120b sealed from each other, so that first brake cylinder 110 is connected via the

aforementioned fluid lines

131, 132, respectively. As described above, the two

fluid spaces

120a, 120b can be brought into and out of controlled simultaneous connection with first brake cylinder 110. Second brake cylinder 120 may be configured to receive a force from actuating member 123 to compress hydraulic fluid within second brake cylinder 120. The force of the driving member 123 is correlated with the braking stroke of the brake pedal 210 of the vehicle 200, so that the braking assistance provided by the assisted brake has a certain degree of functional relationship with the braking treading force expected and applied by the user and the resulting braking stroke, and the controllability of the braking process and the operation feeling of the user are ensured. With this arrangement, the brake booster 100 is configured to transmit a force from one or both of the brake pedal 210 and the driving part 123 by compressing the hydraulic fluid, thereby braking the wheels.

According to the technical scheme of the application, the possibility of selecting multiple brake modes is provided by arranging the two brake cylinders, the brake function can be realized by the aid of the power assisting in normal operation, and the stepping brake can be directly realized by a user in an abnormal state. For example, the first brake cylinder may receive a force generated by a user depressing a brake pedal, and on the one hand may directly compress hydraulic fluid and provide braking based on the force, and on the other hand may sense only a braking stroke generated by the user depressing the brake pedal and simultaneously associate the braking stroke with the drive member to controllably compress hydraulic fluid in the second brake cylinder to provide assisted braking. At the moment, the buffer material area in the first brake cylinder can be used for simulating the real foot feeling of braking for a user, so that the foot feeling of the pedal of the user in various modes is not more different, the brake pedal is more suitable for operation and control, and the situation that the pedal is dropped due to sudden pressure change of hydraulic fluid is avoided. In addition, multiple braking modes of the brake booster can be completed without cooperation of an electronic stability system of the vehicle body, and the reliability is high.

It should be noted that the correlation between the force of the driving member 123 and the braking stroke of the brake pedal 210 of the vehicle 200 described in the foregoing embodiments is a relationship that can be expressed directly or indirectly by a function. For example, the braking stroke of the brake pedal 210 may be indirectly reflected based on the force applied to the brake pedal 210, and the output power thereof may be obtained; the force required to be applied by the driving member 123 can also be evaluated directly based on the braking stroke of the brake pedal 210 after being stressed, so as to obtain the output power of the driving member. Or other implementations consistent with the foregoing concepts, although not described herein, are also intended to be included within the scope of the present application.

On the basis of the foregoing embodiments, several modifications may be made to the various components of the brake booster or their connection position relationships in order to achieve other or additional technical effects, as will be exemplified below.

For example, reference is first made to the drawing to provide a specific embodiment of the first brake cylinder. First brake cylinder 110 includes a first cylinder 111 as a base, and a first piston 112 drivingly reciprocating in first cylinder 111 to compress hydraulic fluid. Wherein the first piston 112 includes a piston main body 112a disposed near the inner side of the first cylinder 111 and a piston push rod 112b disposed far from the inner side of the first cylinder 111, the buffer material region 113 may be disposed between the piston main body 112a and the piston push rod 112b, and the piston push rod 112b is connected to the brake pedal 210. At this time, when the user steps on the brake pedal 210 to apply a force, the piston push rod 112b receives the force from the brake pedal 210 and pushes the piston main body 112a via the cushioning material region 113. In the process, part of the thrust is absorbed by the cushioning material region 113 through elastic deformation or other means, and the remaining force continues to push the piston main body 112a, causing it to perform work against the hydraulic fluid in the first cylinder 111.

On the basis, in order to prevent the reciprocating motion of the first piston 112 and the cushioning material zone 113 from deviating from the normal trajectory, a first stopper 114 may be added to the first cylinder 111, thereby providing two extreme ends of the axial motion of the two in the first cylinder 111.

For another example, a specific embodiment of the second brake cylinder is provided with reference to the drawings. Second brake cylinder 120 includes a second cylinder 121 as a base body and a second hollow piston 122 that is driven by a driving member 123 to reciprocate within second cylinder 121 to compress hydraulic fluid. Specifically, the second hollow piston 122 includes a piston main body first portion provided close to the inside of the second cylinder 121, and a piston main body second portion and a piston rod provided apart from the inside of the second cylinder 121. The first part of the piston body and the inner wall of the second cylinder 121 enclose a fluid space 120a, and the first part of the piston body, the second part of the piston body and the second cylinder 121 together enclose another fluid space 120 b. The two

fluid spaces

120a, 120b are sealed from each other and are connected to first brake cylinder 110 via

fluid lines

131, 132, respectively, and optionally to the vehicle wheels via

fluid lines

141, 142, respectively, through body electronic stability system 220, thereby forming two possible hydraulic fluid flow paths. The piston body second part is connected to the drive member 123 via a piston push rod and is thereby controllably movable and indirectly pushes the piston body first part by means of hydraulic fluid. During movement of the two, the piston body may effect opening or closing of the

fluid lines

131, 132. At this point, when the user depresses the brake pedal 210 to apply a force, since the drive member 123 is already associated therewith, it can correspondingly actuate to apply a force to the second hollow piston 122, thereby compressing the hydraulic fluid within the second cylinder 121 and ultimately effecting braking of the wheel. In the process, the braking function is mainly realized by the cooperation of the driving member 123 and the second cylinder 121, and the user does not need to apply excessive force to compress the hydraulic fluid in the first cylinder 111, but only needs to moderately press the brake pedal to give corresponding control, and at this time, the first brake cylinder 111 can provide the user with the brake pedal feeling when the user presses the brake pedal through the buffering of the buffering material area 113.

On the basis, in order to prevent the reciprocating motion of the second hollow piston 122 from deviating from the normal track, a second stopper 124 may be additionally arranged in the second cylinder 121, so that two extreme end points of the axial motion of the second hollow piston 122 in the second cylinder 121 are provided.

In addition, the second hollow piston 122 includes an end wall and a side wall 122a provided with an opening 122b to realize opening and closing of the

fluid lines

131 and 132. Taking the example of FIG. 1, at this point, if it is desired to communicate second brake cylinder 120 with first brake cylinder 110, then actuating force is no longer applied to second brake cylinder, and second hollow piston 122 is repositioned to the right until fluid line 132 is aligned with opening 122b in side wall 122a of second hollow piston 122, thereby communicating fluid space 120b, as shown in FIG. 3; at this time, the fluid line 131 will also communicate with the fluid space 120a as the second hollow piston 122 moves. Furthermore, if it is desired to disconnect second brake cylinder 120 from first brake cylinder 110, second hollow piston 122 is urged leftward by applying a driving force to the second brake cylinder until

fluid lines

131, 132 are aligned with side walls 122a on either side of opening 122b of second hollow piston 122, respectively, thereby achieving simultaneous closing of both fluid lines and simultaneous disconnection of the respective fluid paths.

An embodiment of the drive member of the brake booster of the present application will now be described with continued reference to fig. 1 to 3. Specifically, the driving part 123 may include a driving motor 123a and an elastic member 123 b. Wherein drive motor 123a is controlled to provide a force to compress hydraulic fluid within second brake cylinder 120 and resilient element 123b resets drive motor 123a when it is stopped, thereby reducing the configuration requirements of drive motor 123a such that it only needs to perform a one-way drive function.

Furthermore, the brake booster may also include a reservoir 150 for storing hydraulic fluid, which is configured to be in fluid communication with first brake cylinder 110, so as to provide timely replenishment of hydraulic fluid in the hydraulic fluid space formed by the two brake cylinders, or to provide a temporary storage space for excess hydraulic fluid, so that the overall hydraulic fluid system has better damping properties.

With continued reference to fig. 1 to fig. 3, the present application further provides an embodiment of a vehicle, where the vehicle 200 may be configured with any embodiment or combination of the aforementioned brake booster 100 according to application requirements, and thus, the technical effects of the aforementioned technical solutions may also be achieved, and therefore, the detailed description is omitted. Further, the vehicle may further include a power pedal 210 and a booster control unit. When the assembly is completed, brake pedal 210 is connected to first brake cylinder 110 of brake booster 100, and the booster control unit controls the force applied by driving member 123 to second brake cylinder 120 based on the braking stroke of brake pedal 210.

It should be appreciated that although the brake booster 100 of the present application may be applicable to various types of vehicles including oil-driven vehicles, electrically-driven vehicles, or hybrid vehicles, it has a better application effect in electrically-driven vehicles or hybrid vehicles including an electric drive source. This is because the electrically driven vehicle generally does not have a vacuum source, and if a conventional vacuum booster is used, a vacuum pump is additionally installed, thereby causing an increase in cost and noise. The booster in this application need not rely on the vacuum source, and has less noise, so it can directly be applied to electrically driven vehicle, and need not make other repacking.

It is also known that mature vehicles are often equipped with vehicle control modules for controlling various components of the vehicle. At this time, the booster control unit in the foregoing embodiment may be a part integrated in the entire vehicle control module, or may be independent control hardware of the brake booster, and when being independent control hardware, it may be disposed in the vehicle, or may be disposed in the brake booster. The brake boosting function of the brake booster of the embodiment can be well realized by the above modes.

In addition to the foregoing embodiments, some sensors may be added to the vehicle to assist in achieving other or additional technical effects. Similarly, such a sensor may be added as a vehicle component or as a component of the brake booster itself, and can achieve a good brake assist effect. As will be exemplified below.

For example, to better enable force detection of brake pedal 210, the vehicle may further include a travel sensor 211 associated to brake pedal 210, the travel sensor 211 being for detecting a braking travel of brake pedal 210 caused by a force applied to brake pedal 210; at this time, the booster control unit controls the force applied by driving member 123 to second brake cylinder 120 based on the brake stroke of brake pedal 210 sensed by stroke sensor 211. In addition, as a concrete implementation form, the stroke sensor can sense the braking stroke of the brake pedal 210 through arrangement on the brake pedal, and can sense the braking stroke of the brake pedal 210 through arrangement of the piston push rod 112b connected with the brake pedal 210 in the brake booster once.

As another example, to better enable proper control of braking based on pressure within the cylinder, the vehicle may further include a first pressure sensor 115 disposed within first brake cylinder 110 of brake booster 100 and a second pressure sensor 125 disposed within second brake cylinder 120. Wherein the booster control unit may control the force applied by driving member 123 to second brake cylinder 120 based on the pressure sensed by first pressure sensor 115 and/or second pressure sensor 125, thereby implementing the final brake control.

Further, although not shown, a vehicle braking control method is also provided herein, which may be applied to any of the embodiments of the vehicle 200 described above, or a combination thereof.

The control method may include at least a first braking mode and a second braking mode. In a first braking mode (generally understood as a conventional braking mode), as shown in fig. 1, a user may step on a brake pedal 210 when desiring to brake, at which time the brake pedal 210 is forcibly moved and pushes a first piston 112, and at the same time, the booster control unit controls a force applied to a second brake cylinder 120 by a driving member 123 based on a braking stroke of the brake pedal 210 to push a second hollow piston 122 to compress a hydraulic fluid, and finally brake a wheel by the compressed fluid. At this point, the movement of second hollow piston 122 closes

fluid lines

131, 132, i.e., decouples first brake cylinder 110 from second brake cylinder 120, so that all of the hydraulic fluid that is compressed to brake the wheels comes from second brake cylinder 120 (and further adjustments may be made via body electronic stability system 220, if present), and first brake cylinder 110 need not perform any more braking functions, at which point only cushioning of brake pedal 210 by cushioning material region 113 is needed to simulate the user's feel of the brake foot. At the same time, the movement of the first piston 112 closes the fluid line 161 so that the reservoir 150 need not perform a replenishing or staging function.

As shown in fig. 2, in the second braking mode (generally understood as an external braking request mode), the user himself or herself does not realize braking of the vehicle, and at this time, when there is an arbitrarily set external braking request triggering condition, such as an occurrence of an excessive proximity to the preceding vehicle, the booster control unit directly controls the driving part 123 to apply force to push the second hollow piston 122 to compress the hydraulic fluid based on the external request signal, and finally brakes the wheels by the compressed fluid. At this point, the movement of second hollow piston 122 also closes

fluid lines

131, 132, i.e., first brake cylinder 110 is decoupled from second brake cylinder 120, so that the hydraulic fluid that is compressed and thus brakes the wheels comes from second brake cylinder 120 (and can be further regulated via body electronic stability system 220, if present), without first brake cylinder 110 having to perform any further braking function. At this time, since the user does not step on the brake pedal 210, the first piston 112 does not move and closes the fluid line 161, so that the reservoir 150 may perform a replenishing or temporarily storing function. If the user realizes that the brake should be applied later and further steps on the brake pedal, the buffer material area 113 can buffer the brake pedal 210, so that the brake pedal does not drop suddenly, the user's operation feeling is maintained, and the repeated brake is compatible.

It should be noted that the external request signal generated based on the external braking request start condition may be any preset braking request signal triggered by a device other than the brake booster (e.g., an external sensor or an external component).

Further, for example, when the vehicle 200 includes the body electronic stability system 220, one embodiment of the control method may further include a third braking mode and/or a fourth braking mode. In the third braking mode (generally understood as the degraded braking mode), the body electronic stability system 220 may malfunction, and the brake assist capability is lost. At this time, when the user desires to brake, he or she depresses the brake pedal 210, the brake pedal 210 is forced to move and push the first piston 112, and at the same time, the booster control unit controls the force applied to the second brake cylinder 120 by the driving member 123 based on the braking stroke of the brake pedal 210 and the hydraulic pressure in the first brake cylinder 110 to push the second hollow piston 122 to compress the hydraulic fluid, and the wheel is directly braked by the compressed fluid without the cooperation of the body electronic stability system 220. At this point, the movement of second hollow piston 122 closes

fluid lines

131, 132, i.e., decouples first brake cylinder 110 from second brake cylinder 120, and since body electrical stability system 220 has failed, hydraulic fluid that is compressed to brake the wheels is provided from second brake cylinder 120, and neither first brake cylinder 110 nor body electrical stability system 220 is required to perform any further braking functions. At this time, the brake pedal 210 is only cushioned by the cushion material region 113 to simulate the feeling of the user's brake foot. At the same time, the movement of the first piston 112 closes the fluid line 161 so that the reservoir 150 need not perform a replenishing or staging function.

Alternatively, the driving member 123 may be out of order, and the brake assist capability may be lost. At this time, when the user desires to brake, he or she may step on the brake pedal 210, and the brake pedal 210 will be forced to move and push the first piston 112, and at the same time, the control unit of the body electronic stability system 220 may determine the pressure difference that is insufficient for implementing braking based on the current own hydraulic pressure, so as to control the body electronic stability system 220 to automatically adjust the build-up pressure to finally implement the braking function. Alternatively, it may be determined whether driving member 123 of second brake cylinder has actually failed based on the braking stroke of brake pedal 210 or the hydraulic pressure in first brake cylinder 110, thereby triggering control for adjusting the hydraulic pressure of body electronic stability system 220 itself. The foregoing processes may each be used to brake a wheel directly with compressed fluid without the cooperation of drive member 123 and second brake cylinder 120. At this time, the brake pedal 210 is only cushioned by the cushion material region 113 to simulate the feeling of the user's brake foot.

Similarly, the control unit of the electronic body stabilization system in the foregoing embodiment may also be a part integrated in the vehicle control module, or may be independent control hardware of the electronic body stabilization system, and when the control unit is independent control hardware, it may be disposed in the vehicle or in the electronic body stabilization system. The aforementioned manner can well realize the auxiliary braking function in the present embodiment.

Further, as shown in fig. 3, in the fourth braking mode (generally understood as a mechanical braking mode), both the driving part 123 and the body electronic stability system 220 may fail, and thus the braking assistance capability is lost at the same time. At this time, when the user desires to brake, he or she steps on the brake pedal 210, the brake pedal 210 is forced to move and push the first piston 112, the first piston 112 compresses the hydraulic fluid in the first cylinder 111, and the wheel is braked directly by transmitting the compressed hydraulic fluid, without cooperation of the driving part 123 and the body electronic stability system 220. At this time, due to the lack of the boosting means, the user needs to apply a relatively larger pedaling force, and at this time, the cushioning material region 113 still cushions a part of the force from the brake pedal 210 of the vehicle 200, but the remaining force will be sufficient to compress the hydraulic fluid to achieve braking. At this time, since driving member 123 is not operated, second hollow piston 122 is not moved and

fluid lines

131, 132 are not closed, and therefore, hydraulic fluid in first brake cylinder 110 is allowed to flow through second brake cylinder 120 and body electronic stability system 220, and finally to the wheels to effect braking. At the same time, the movement of the first piston 112 closes the fluid line 161 so that the reservoir 150 need not perform a replenishing or staging function.

It should be noted that the brake booster and other parts of the vehicle provided by the present application may be designed, manufactured, and sold separately, or they may be assembled together and sold as a whole. Whether formed as a monomer before combination or as a whole after combination, are within the scope of the present application.

The above detailed description is merely illustrative of the present application and is not intended to be limiting. In the present application, relative terms such as left, right, up, and down are used to describe relative positional relationships, and are not intended to limit absolute positions. Various changes and modifications can be made by one skilled in the art without departing from the scope of the present application, and all equivalent technical solutions also belong to the scope of the present application, and the protection scope of the present application should be defined by the claims.

Claims

1. A brake booster for a vehicle, comprising:

a first brake cylinder (110) configured to receive a force from a brake pedal (210) of a vehicle (200) to compress hydraulic fluid within the first brake cylinder (110), and a cushioning material zone (113) is provided for cushioning the force from the brake pedal (210) of the vehicle (200); and

a second brake cylinder (120) having two fluid spaces (120 a, 120 b) which are sealed off from one another, the two fluid spaces (120 a, 120 b) being configured to be connected to the first brake cylinder (110) by way of a fluid line (131, 132) and being controlled in each case to be connected to and disconnected from the first brake cylinder (110); the second brake cylinder (120) is configured to receive a force from a driving member (123) to compress hydraulic fluid within the second brake cylinder (120), wherein the force of the driving member (123) is associated with a braking stroke of a brake pedal (210) of the vehicle (200);

wherein the brake booster (100) is configured to transmit a force from the brake pedal (210) and/or the driving part (123) to brake a wheel by compressing a hydraulic fluid.

2. A brake booster as set forth in claim 1 wherein:

the first brake cylinder (110) comprises:

a first cylinder (111); and

a first piston (112) drivingly reciprocated within the first cylinder (111) to compress hydraulic fluid; the first piston (112) comprises a piston main body (112 a) and a piston push rod (112 b); wherein the cushioning material zone (113) is used for cushioning a force from a piston tappet (112 b), and the piston tappet (112 b) is used for connecting a brake pedal (210) of a vehicle (200); and/or

The second brake cylinder (120) comprises:

a second cylinder (121); and

a second hollow piston (122) driven by the driving member (123) to reciprocate within the second cylinder (121) to compress hydraulic fluid and open or close the fluid line (131, 132); wherein the second hollow piston (122) separates the two mutually sealed fluid spaces (120 a, 120 b) within the second cylinder (121).

3. A brake booster as set forth in claim 2 wherein:

-providing a first stop (114) within the first cylinder (111), the first stop (114) being adapted to limit the axial movement of the cushioning material zone (113) within the first cylinder (111); and/or

A second stopper (124) is provided in the second cylinder (121), and the reciprocating motion of the second hollow piston (122) in the second cylinder (121) is restricted by the second stopper (124).

4. A brake booster according to claim 2, characterized in that the second hollow piston (122) comprises an end wall and a side wall (122 a) provided with an opening (122 b); wherein one of the fluid lines (131, 132) is aligned with an opening (122 b) in a side wall (122 a) of the second hollow piston (122) when the second brake cylinder (120) is connected to the first brake cylinder (110), and the fluid line (131, 132) is aligned with a side wall (122 a) of the second hollow piston (122) when the second brake cylinder (120) is disconnected from the first brake cylinder (110).

5. A brake booster according to any one of claims 1 to 4, characterized in that the drive member (123) comprises a drive motor (123 a) and an elastic element (123 b), the drive motor (123 a) being controlled to provide a force to compress the hydraulic fluid in the second brake cylinder (120), and the elastic element (123 b) resetting the drive motor (123 a) when it is deactivated.

6. Brake booster according to one of claims 1 to 4, characterized in that it further comprises a reservoir (150) for storing hydraulic fluid; the reservoir (150) is configured to be in fluid communication with the first brake cylinder (110).

7. A vehicle, characterized by comprising: the brake booster (100) of any one of claims 1 to 6; a brake pedal (210) and a booster control unit; wherein a brake pedal (210) is connected to the first brake cylinder (110) of the brake booster (100), the booster control unit controlling a force applied by the drive member (123) to the second brake cylinder (120) based on a braking stroke of the brake pedal (210).

8. The vehicle of claim 7, further comprising: a travel sensor associated to the brake pedal (210) for detecting a travel of the brake pedal (210) caused by a force applied to the brake pedal (210); wherein the booster control unit controls a force applied by the driving member (123) to the second brake cylinder (120) based on the stroke of the brake pedal (210) sensed by the stroke sensor.

9. The vehicle of claim 7, further comprising: a first pressure sensor arranged in the first brake cylinder (110) of the brake booster (100); and a second pressure sensor arranged in the second brake cylinder (120); wherein the booster control unit controls the force applied by the driving member (123) to the second brake cylinder (120) based on the pressure sensed by the first pressure sensor and/or the second pressure sensor.

10. A vehicle brake control method for a vehicle (200) according to any one of claims 7 to 9, characterized by comprising:

a first braking mode in which a brake pedal (210) of the vehicle (200) is forced to move, the booster control unit controlling a force applied by the driving member (123) to the second brake cylinder (120) based on a braking stroke of the brake pedal (210) to compress hydraulic fluid to brake a wheel; and the cushioning material zone (113) cushions a force from a brake pedal (210) of the vehicle (200); and

a second braking mode, the booster control unit controlling a force applied by the drive component (123) to the second brake cylinder (120) based on an external request signal to compress hydraulic fluid to brake a wheel; wherein the external request signal is a brake request signal from a component other than the brake booster.

11. The vehicle brake control method according to claim 10, wherein when the vehicle (200) includes a body electronic stability system (220), the control method further includes:

a third braking mode in which a brake pedal (210) of the vehicle (200) is forced to move upon failure of the body electronic stability system (220), the booster control unit controlling a force applied by the driving member (123) to the second brake cylinder (120) based on a braking stroke of the brake pedal (210) and a hydraulic pressure in the first brake cylinder (110) to compress a hydraulic fluid to brake a wheel; and the cushioning material zone (113) cushions a force from a brake pedal (210) of the vehicle (200); or, upon failure of the driving part (123), adjusting, by a control unit of the body electronic stability system (220), its hydraulic pressure based on a pressure difference within the body electronic stability system (220) or on a braking stroke of a brake pedal 210 or on a hydraulic pressure within a first brake cylinder (110) to compress hydraulic fluid to brake a wheel; and the cushioning material zone (113) cushions a force from a brake pedal (210) of the vehicle (200); and/or

A fourth braking mode in which, in the event of a failure of the drive member (123) simultaneously with the body electronic stability system (220), a brake pedal (210) of the vehicle (200) is forced to move and compress the first brake cylinder (110) to compress hydraulic fluid to brake a wheel; and the cushioning material zone (113) cushions a force from a brake pedal (210) of the vehicle (200).