CN115959100A - Decoupling type brake boosting device and vehicle - Google Patents

Abstract

The embodiment of the invention provides a decoupling type brake boosting device and a vehicle. The decoupled brake assist device includes: input rod, plunger, helping hand motor and control unit, output push rod and footboard feel analogue means, the analogue means includes is felt to the footboard: the pedal feel simulation device comprises an axial guide rod, a support plate and a pedal feel simulation spring, wherein the pedal feel simulation spring is arranged on the axial guide rod and abuts against the support plate. According to the decoupling type brake boosting device of the embodiment, not only can the stroke of the brake pedal be directly detected and braking can be carried out according to the detected pedal stroke, but also the pedal feeling close to that of a traditional brake system or a vacuum booster can be simulated.

Description

Decoupling type brake boosting device and vehicle

Technical Field

The invention relates to the field of vehicle brake boosting, in particular to a decoupling type brake boosting device with a pedal feeling simulation function and a vehicle.

Background

In order to enable a driver of a motor vehicle to comfortably actuate an actuating element of a brake system, such as, for example, a brake pedal, the brake system generally has a brake booster. Brake systems with brake boosters are often referred to as brake systems with brake boosting. In the case of a vehicle, the brake booster assists the driver in building up brake pressure when he depresses the brake pedal.

The existing brake booster device for the passenger vehicle comprises a vacuum booster and an electronic booster, wherein the vacuum booster is widely applied to the fuel passenger vehicle, and the electronic booster is widely applied to a new energy passenger vehicle. However, for new energy vehicles, especially for electric vehicles, in order to recover braking kinetic energy, in the process of stepping on the brake pedal, it is desirable to participate in or realize braking through the dragging action of the main motor of the entire vehicle (the motor reduces the rotation speed), rather than realize braking completely by the friction plate of the vehicle braking device, and at the same time, the main motor of the entire vehicle converts the kinetic energy of the vehicle into electric energy to feed back to the electric storage device of the entire vehicle, thereby realizing energy recovery.

In the existing brake system, the coupled brake booster and the ESP hev with an energy storage device are generally required to cooperatively work to realize the functions of braking, kinetic energy recovery and the like, the scheme requires that the coupled brake booster and the ESP hev are precisely matched in the braking process, the requirement on matching of the whole vehicle brake is high, and the cost of the system is high; the functions of braking, kinetic energy recovery and the like can be realized by independently utilizing the decoupling type integrated braking device, but the decoupling type integrated braking device cannot meet the requirement of high-grade automatic driving.

The brake system scheme expected by the market is that the functions of braking, kinetic energy recovery and the like are realized by utilizing the cooperative work of a decoupling type brake boosting device and a standard ESP, and the decoupling type brake device can simulate the pedal feeling close to the traditional brake system with a vacuum booster so as to enable a driver to adapt quickly.

Disclosure of Invention

It is an aim of embodiments of the present invention to solve or at least mitigate the problems in the prior art.

According to some aspects, embodiments of the present invention are directed to how to provide a function of directly detecting a brake pedal stroke and braking according to the detected pedal stroke for a decoupled brake booster, and provide a technical solution for a decoupled brake booster that is convenient for manufacturing a production line and simplifies assembly.

Embodiments address the above stated problems by providing a pedal feel simulator assembly and decoupled brake boosting device.

Specifically, according to an aspect of the embodiment, there is provided a brake servo device including:

the input rod is used for being connected with a brake pedal;

the input rod drives the plunger to move axially when the brake pedal is stepped on;

a displacement sensor assembly that senses axial displacement of the input rod or the plunger;

the brake system comprises a power-assisted motor and a control unit, wherein the control unit controls the power-assisted motor to work so as to output brake power-assisted torque;

an output push rod operatively coupled with the assist motor to receive the brake assist torque and perform an axial displacement to output a braking force to a brake cylinder;

wherein, the braking booster unit still includes: a pedal feel simulation device comprising:

an axial guide rod located radially outward of the plunger;

the outer side of the supporting plate is sleeved on the axial guide rod, and when the plunger contacts with the middle of the supporting plate, the supporting plate is pushed by the plunger to move towards the brake master cylinder together; and

a pedal feel analog spring disposed on the axial guide rod, the pedal feel analog spring abutting against the support plate to apply a reaction force to the support plate.

In another aspect, a vehicle is also provided, comprising a decoupled brake boosting device according to various embodiments.

The decoupled brake booster according to embodiments is able to simulate a "pedal feel" that is close to a conventional brake system with a vacuum booster.

Drawings

The disclosure of the embodiments will become more readily understood by reference to the accompanying drawings. As is readily understood by those skilled in the art: these drawings are for illustrative purposes only and are not intended to constitute a limitation on the scope of the embodiments. Moreover, in the drawings, like numerals are used to indicate like parts, and in which:

fig. 1 and 2 show perspective views of a decoupled brake booster according to an embodiment with and without a motor and a control unit;

FIGS. 3, 4 and 5 are perspective views from various angles of the decoupled brake assist device of FIG. 1 with the motor, control unit and master cylinder removed, wherein one of the links is removed from FIG. 4 to show internal structure;

FIG. 6 illustrates a perspective view of a portion of components of a decoupled brake boosting device according to one embodiment of the embodiments;

FIG. 7 shows a longitudinal sectional view of the decoupled brake booster of FIG. 1;

figures 8 to 11 show longitudinal cross-sectional views of the decoupled brake booster of figure 1 at various stages during pedal depression;

FIG. 12 shows a theoretical pedal force versus pedal distance curve for the decoupled brake boosting of FIG. 1;

FIG. 13 shows a longitudinal cross-sectional view of an exemplary modification of the decoupled brake boosting of FIG. 1;

FIG. 14 shows a longitudinal section view of another exemplary modification of the decoupled brake booster of FIG. 1;

figures 15 and 16 show different angled perspective views of a decoupled brake booster according to another embodiment;

FIG. 17 shows a perspective view of the decoupled brake booster of FIG. 15 with the motor and control unit removed;

FIG. 18 shows a longitudinal cross-sectional view of the decoupled brake booster of FIG. 15;

FIG. 19 shows an exemplary modification of the decoupled brake booster of FIG. 15;

figures 20 and 21 show perspective views of a decoupled brake booster according to another embodiment with and without a motor and a control unit; and

fig. 22 shows a longitudinal sectional view of the decoupled brake booster of fig. 20 and 21.

Detailed Description

It is easily understood that, according to the technical solutions of the embodiments, a person skilled in the art may propose various alternative structural modes and implementation modes without changing the spirit of the embodiments. Therefore, the following detailed description and the accompanying drawings are only exemplary illustrations of the technical solutions of the embodiments, and should not be construed as being all of the embodiments or limiting or restricting the technical solutions of the embodiments.

The directional terms upper, lower, left, right, front, rear, front, back, top, bottom and the like that are or may be mentioned in this specification are defined relative to the configurations shown in the drawings, and are relative concepts that may be changed accordingly depending on the position and the use state of the device. Therefore, these and other directional terms should not be construed as limiting terms. Furthermore, the terms "first," "second," "third," and the like, are used for descriptive and distinguishing purposes only and are not to be construed as indicating or implying relative importance of the respective components.

A decoupled brake boosting device according to one embodiment is described with reference to fig. 1 to 7. The decoupled brake assist device includes: an assist motor and its control unit 28 for providing an initial torque for generating a braking assist force, the control unit for controlling the operation of the assist motor based on various information; a gear transmission assembly consisting of two or more gears for amplifying and transmitting the motor torque to the spindle nut 24, for example, in the illustrated embodiment, the gear on the output shaft of the assist motor is meshed with a dual gear 29, and the dual gear 29 is further meshed with a sun gear 241 on the spindle nut 24, the sun gear 241 being engageable with the spindle nut 24 by splines, thereby amplifying and transmitting the torque of the assist motor to the spindle nut 24; a main housing 100, the main housing 100 for supporting and covering various components inside the booster motor; the main shaft nut 24 and the main shaft 21 are coaxially arranged, an inner ring of the main shaft nut 24 and an outer ring of the main shaft 21 are provided with matched threads, the inner end of the main shaft 21 is fixedly connected with an anti-rotation plate 91, the outer ring of the anti-rotation plate 91 is further sleeved on a pair of through rods 9 arranged on the main shell 100 through a shaft sleeve 95 for example, so that the anti-rotation plate 91 and the main shaft 21 cannot rotate, and the torque transmitted from the power-assisted motor through the main shaft nut 24 is converted into axial movement of the main shaft 21; a penetration rod 9 having one end connected and fixed to the master cylinder 50 and the other end connected to the main housing 100, the middle section for being assembled with the rotation preventing plate 91 to guide the axial movement of the rotation preventing plate 91 and to prevent the rotation preventing plate 91 from rotating; a support member 25 having one end connected to a return spring holder 59 on the back side of the output push rod 5 and the other end connected to a rotation preventing plate 91 for transmitting the thrust of the main shaft 21 to the output push rod 5; an output push rod 5 for outputting a thrust to a master cylinder 50 of the decoupled brake booster; a return spring 58 acting on a return spring holder 59 supporting the back side 51 of the output push rod 5 for holding the spindle, the rotation preventing plate, the output push rod, and the gear transmission assembly at an initial position or pushing the spindle, the rotation preventing plate, the pedal feel simulator, the output push rod, and the gear transmission assembly back to the initial position after braking is completed.

In addition, the brake boosting device further includes: an input rod 1, the input rod 1 comprising an outer end 11 and an inner end 12, the outer end 11 being adapted to be connected to a brake pedal for receiving and transmitting a driver applied brake pedal force; the plunger 2 is connected with the inner end 12 of the input rod 1, the plunger 2 is positioned on the inner side of the hollow main shaft 21 and can move along the axial direction relative to the main shaft 21, and when a brake pedal is pressed, the input rod 1 drives the plunger 2 to move along the axial direction; a displacement sensor assembly, for example comprising: through the magnet 94 connected with the plunger 2 by the bracket 93 and the fixed magnet sensor assembly 99, the magnet sensor assembly 99 senses the axial displacement of the magnet 94 and the plunger 2 by sensing the change of the magnetic field caused by the movement of the magnet 94, thereby sensing the stroke of the brake pedal and feeding back to the control unit. In an alternative embodiment, a displacement sensor assembly may be connected to the input rod 1 to detect axial displacement of the input rod 1, thereby sensing the stroke of the brake pedal. In alternative embodiments, the displacement sensor assembly may detect the travel of the brake pedal based on other means, such as a light sensor or the like. The decoupled brake boosting device according to the embodiment further includes: an axial guide rod 7, such as a pair of axial guide rods 7, a support plate 6, and an outer side 62 of the support plate is sleeved on the axial guide rod 7, in the embodiment of fig. 7, in an initial state, the plunger 2 is spaced from the support plate 6, the plunger 2 is contacted with the support plate 6 along with the movement of the plunger 2, and the support plate 6 is pushed by the plunger 2 to move towards the brake master cylinder 50 together; a pedal feel simulation spring 82,83 provided on the axial guide rod 7, a pedal feel simulation spring 82,83 fitted around the axial guide rod 7 and its initial resistance acting on the support plate 6 to abut against a boss portion 79 constructed in the middle of the axial guide rod, the pedal feel simulation spring 82,83 being compressed by the support plate 6 during movement of the pedal to provide a reaction force, i.e., pedal feel feedback force, to the support plate 6; the starting power spring 23 is sleeved on the input rod 1, the left end of the starting power spring is abutted against the spindle 21, the right end of the starting power spring is abutted against the stop ring on the input rod 1, and the starting power spring 23 is used for realizing a first-stage pedal feeling, namely an initial pedal feeling before the end part of the plunger 2 is contacted with the support plate 6; disc spring assembly 87, disc spring assembly 87 is comprised of 2 or more than 2 disc springs and is connected to inner end 26 of plunger 2, shown in the illustrated embodiment as two concentrically disposed disc springs, and disc spring assembly 87 contacts support plate 6 and is compressed as plunger 2 moves, thereby providing a second step feel. In addition, as will be described in detail below, the pedal feel simulator spring 82,83 provides a third stage pedal feel.

In the embodiment, the outer ring of the plunger 2 is provided with the spindle 21, the outer ring of the spindle 21 is provided with the spindle nut 24, and the spindle 21 and the spindle nut 24 are in threaded engagement. In the embodiment, a through hole is formed in the center of the anti-rotation plate 91, and the through hole is sleeved on the inner end of the spindle 21 and is fixedly connected with the spindle 21. Alternatively, the anti-rotation plate 91 may be connected to the main shaft by other means. Sliding sleeves are respectively arranged at two ends of the anti-rotation plate 91 and are respectively sleeved on the through rod 9, so that the rotation of the anti-rotation plate 91 and the main shaft 21 is limited. A hollow gear 241 is sleeved on the outer side of the spindle nut 24, the hollow gear 241 is in spline connection with the spindle nut 24, and the assisting motor drives the hollow gear 241 through a reduction gear set. Since the spindle 21 is threadedly engaged with the spindle nut 24 and the rotational movement of the spindle 21 is restricted from rotation, the rotation of the spindle nut 24 will cause the spindle 21 to move in the axial direction. As clearly shown in fig. 7 and 8, the support members 25 are symmetrically arranged on both sides of the plunger 2 and are located on the side of the rotation preventing plate 91 adjacent to the master cylinder. One end of the supporting member 25 is fixedly connected with the rotation preventing plate 91, and the other end is fixedly connected with the return spring holder 59 on the back side of the output push rod 5, and the supporting member and the plunger 2 are not connected and can respectively and independently move along the axial direction. Therefore, driven by the booster motor, the axial movement of the spindle 21 will drive the rotation preventing plate 91, the supporting member 25 and the output push rod 5 to move leftward together, and finally the output push rod 5 transmits the thrust to the master cylinder 50, thereby driving the master cylinder 50 to establish the braking pressure.

As can be seen from fig. 3 to 7, the decoupled brake booster according to the exemplary embodiment uses a total of two support elements 25, and the two support elements 25 and the anti-rotation plate 91 are configured as a through groove with three open sides, in which the middle part 61 of the support plate 6 is located, and in which the support plate 6 can be axially translated. Disc spring assembly 87 and magnet holder 93 are fixedly connected to plunger 2, disc spring assembly 87 and magnet holder 93 extend from the through slot between the two supports 25, and disc spring assembly 87 is axially translatable within the through slot, but its rotational movement along the axis is limited. Through holes symmetrical around the axis of the main shaft 21 are formed in two sides of the anti-rotation plate 91, and the through holes of the anti-rotation plate 91 are matched with bosses at two ends of the magnet support respectively, so that the influence on the magnet support 93 when the anti-rotation plate 91 moves can be avoided.

It can be seen that the axial movements of the spindle 21, the rotation prevention plate 91 and the support 25 driven by the motor and the axial movements of the input rod 1, the plunger 2, the disc spring assembly 87, the magnet holder 93 and the support plate 6 can be performed in a space in the middle without interfering with each other.

In the embodiment, referring to fig. 7, the axial guide rod 7 has a stopper ring 71 spaced apart from the support plate 6, a spacer 72 is provided between the stopper ring 71 and the support plate 6, a second pedal feel simulation spring 83 is provided between the spacer 72 and the support plate 6, and a first pedal feel simulation spring 82 is provided between the spacer 72 and the stopper ring 71. In an alternative embodiment, only one pedal feel analog spring 82 may be disposed between the support plate 6 and the retainer ring 71.

Different from the existing brake boosting device for passenger vehicles (wherein the input rod 1 and the output push rod 5 are connected to move together), the decoupling type brake boosting device according to the embodiment can be constructed into two working modes of decoupling and coupling according to the contact state of the input rod 1 and the output push rod 5, and can be applied to different brake states of different types of vehicles;

when the decoupling type brake boosting device is applied to a new energy automobile, particularly an electric automobile, and a driver treads a brake pedal to brake, a control unit can determine whether a brake boosting module works or not according to the current automobile speed and a detected displacement signal (namely pedal travel) of a plunger 2, if the pedal travel is smaller than a threshold value (or called decoupling distance) and the dragging torque of a main motor of the whole automobile can meet the brake requirement under the current automobile speed, the brake boosting module does not work, namely a brake boosting motor 28 does not work, an output push rod 5 cannot move along with the axial displacement of the plunger 2, namely the displacement of the pedal cannot cause the output push rod 5 to output brake force; if the pedal travel is smaller than a threshold value (or called decoupling distance) and the dragging torque of the main motor of the whole vehicle cannot meet the braking requirement at the current vehicle speed, the brake boosting module quickly responds to a displacement signal of the plunger 2 to start working, namely the brake boosting motor starts to output torque, the output push rod 5 is driven by the motor to move along with the axial displacement of the plunger 2, so that the brake main cylinder 50 is pushed to build pressure, and at the moment, the brake boosting module cooperates with the dragging torque of the main motor of the whole vehicle according to the detected displacement signal of the plunger 2 to realize braking together. In the above process, although the input rod 1 and the plunger 2 are displaced, they are not always in contact with the output push rod 5, which is the decoupling operation mode of the decoupling type brake assisting device, and the stroke of the input rod 1, i.e. the decoupling stroke, can be set to be 5mm-18mm, for example, corresponding to the stroke before the disc spring group 87 contacts the support plate 6 and reaches the maximum deformation. If the pedal stroke is larger than or equal to the threshold value, namely after the pedal stroke is equal to or larger than the threshold value, the decoupling type brake power assisting device enters a coupling working mode, a main motor of the whole vehicle can not participate in braking in the coupling working mode, the control unit controls the brake power assisting module to work according to the current vehicle speed and the detected displacement of the plunger 2, the output push rod 5 moves along with the axial displacement of the plunger 2 under the driving of the motor, and therefore the brake main cylinder 50 is pushed to build pressure, and finally the braking of the whole vehicle is achieved. Thus, during the coupling stroke, the braking force is substantially provided by the master cylinder 50.

When the brake boosting device according to the embodiment is applied to an internal combustion locomotive and a driver treads a brake pedal to brake, the brake boosting module quickly responds to a displacement signal of the plunger 2 to start working, namely, the brake boosting motor starts to output torque, the output push rod 5 is driven by the motor to move along with the axial displacement of the plunger 2, so that a brake master cylinder is pushed to build pressure, and at the moment, the brake boosting module outputs a corresponding braking force according to the detected displacement signal of the plunger 2, so that the braking requirement of the driver is met.

In this type of decoupled brake booster, it is desirable that the decoupled brake booster according to the embodiment can simulate the pedal feel of a conventional brake booster because there is no mechanical coupling between the input rod 1 and the plunger 2 and the output push rod 5 during the decoupling stroke, so that the driver will not feel the reaction force fed back by the brake system when stepping on the brake pedal, and therefore will not feel the pedal feel during braking that is already familiar or adapted.

To this end, the decoupled brake boosting device according to an embodiment further comprises: the pedal feel simulation device includes: an axial guide rod 7 located radially outside said plunger 2, the axial guide rod 7 being attachable to the gear housing 100; a support plate 6, an outer side 62 of the support plate 6 being fitted over the axial guide rod 7, for example a bushing fixed to the support plate 6 being fitted over the guide rod 7, the support plate 6 being pushed by the plungers to move together towards the brake master cylinder 50 when the plungers are in contact with an inner side 61 of the support plate; a baffle ring 71, a baffle ring 71 separated from the support plate 6 is arranged on the axial guide rod 7, a spacer 72 is arranged between the baffle ring 71 and the support plate 6, a first pedal feeling simulation spring 82 is arranged between the spacer 72 and the baffle ring 71, a second pedal feeling simulation spring 83 is arranged between the spacer 72 and the support plate 6, and the initial resistance force provided by the pedal feeling simulation springs 82 and 83 acts on the support plate 6 to enable the support plate to abut against a boss part 79 constructed in the middle of the axial guide rod. The pedal feel analog springs 82 and 83 are compressed by the support plate 6 during the movement of the brake pedal to provide a reaction force, i.e., a pedal feel feedback force, to the support plate 6. The second pedal feeling simulation spring 83 and the spacer 72 are optional components, and whether the pedal feeling simulation spring 83 and the spacer 72 need to be arranged or not can be selected according to actual requirements. The starting power spring 23 sleeved on the input rod has the left end abutting against the main shaft 21 and the right end abutting against the stop ring on the input rod 1. The initial power spring 23 provides a counterforce after being compressed, and is used for realizing a first stage pedal feeling, namely an initial pedal feeling; the disc spring assembly 87, the disc spring assembly 87 is composed of 2 or more than 2 disc springs, and also participates in realizing pedal feeling.

A specific pedal feel simulation process will be described with continued reference to fig. 8 to 11. When the driver steps on the brake pedal, when the thrust generated by the brake pedal is greater than the initial resistance of the initial power spring 23, the input rod 1 and the plunger 2 start to be pushed to move towards the brake master cylinder 50, and meanwhile, the initial power spring 23 starts to be compressed, so that the first stage pedal feeling starts to be generated, which corresponds to the section A in the pedal feeling curve of fig. 12 and the processes of fig. 7 to 8; when the brake pedal is further depressed, the input rod 1 and the plunger 2 continue to move toward the master cylinder 50, and when one of the disc springs of the disc spring assembly 87 comes into contact with the support plate 6, the second stage pedal feel starts. As the brake pedal is further depressed, the input rod 1 and the plunger 2 continue to move toward the master cylinder 50, and the disc springs of the disc spring assembly 87 are sequentially deformed, which forms a second step feeling corresponding to the section B in fig. 12 and the processes in fig. 8 to 9, as shown in fig. 12, the second step feeling curve B has two sections corresponding to the case of 2 disc springs, and the step feeling curve of the section can be changed if another number of disc springs are selected. When the brake pedal is continuously stepped on, the input rod 1 and the plunger 2 continue to move towards the brake master cylinder 50, when the plunger 2 abuts against the supporting plate 6, the deformation of the disc spring assembly 87 reaches the maximum value, at this time, the second stage pedal feeling is finished, and the third stage pedal feeling is started. Continuing to depress the brake pedal, the input rod 1 and plunger 2 push the support plate 6 to move in the direction of the master cylinder, and the support plate 6 starts to compress the pedal feel simulation springs 82,83, which process forms a third step feel and optionally a fourth step feel, corresponding to the processes of sections C and D in fig. 12 and fig. 9-11, wherein the first pedal feel springs 82 and 83 are first compressed together until the condition of fig. 10 (section C), i.e. after the spacer 72 abuts against the support plate 6, and then only the first pedal feel simulation spring 82 is compressed (section D). When the brake pedal is continuously stepped on, the input rod 1 and the plunger 2 push the support plate 6 to move towards the direction of the brake master cylinder 50, when the pedal stroke exceeds 20mm for example, the support plate 6 starts to abut against the return spring retainer 59, the third stage of pedal feeling is ended, and the subsequent pedal feeling is mainly formed by deformation of the pedal feeling simulator and other parts of the whole vehicle brake system.

During the operation of the pedal simulator, reaction forces are generated when the starting force spring 23, the disc spring assembly 87, the pedal feeling simulation springs 82 and 83 and the like are deformed, the resultant force of all the reaction forces is transmitted to the brake pedal through the plunger 2 and the input rod 1, the magnitude of the input force is equal to the magnitude of the input force applied to the input rod 1 when the driver steps on the brake pedal, the direction of the input force is opposite to the direction of the input force, the resultant force of the reaction forces is fed back to the driver through the brake pedal and is sensed by the driver, and the pedal feeling during braking which the driver is familiar or adapted is formed by combining the displacement of the brake pedal at the moment.

The decoupled brake boosting device according to this embodiment will be described in detail with continued reference to fig. 7 to 12. In this embodiment, the inner end 26 of the plunger 2 is connected to a laminated spring assembly 87, for example, comprising two disc springs in the illustrated embodiment, arranged in parallel and having different radii of curvature. The two disc springs 87 are spaced apart from the support plate 6 with a gap therebetween, which can be used as a decoupling distance, and different decoupling distances, for example, 5-18mm, can be set according to different vehicle types or the requirements of the entire vehicle. Further, in this embodiment, a power spring 23 is provided between the main shaft 21 and the input lever 1. When the brake pedal is initially depressed, as in the process of fig. 7 to 8, the input rod 1 pushes the plunger 2 to move axially, and the initial force spring 23 is compressed to provide a reaction force, which corresponds to the section a in fig. 12. As described in detail above, when the brake booster is used in an electric vehicle, in the process, that is, when the pedal stroke is smaller than the decoupling distance, the control unit may determine whether the brake booster module works according to the current vehicle speed and the detected displacement signal of the plunger 2, if the drag torque of the main motor of the entire vehicle can meet the braking requirement at the current vehicle speed, the brake booster module does not work, that is, the brake booster motor will not work, the output push rod 5 will not move along with the axial displacement of the plunger 2, that is, the displacement of the pedal will not cause the output push rod 5 to output the braking force; if the dragging torque of the main motor of the whole vehicle cannot meet the braking requirement under the current vehicle speed, the brake boosting module quickly responds to the displacement signal of the plunger 2 to start working, namely the brake boosting motor starts to output the torque, the output push rod 5 can move along with the axial displacement of the plunger 2 under the driving of the motor so as to push the brake main cylinder 50 to build pressure, and the brake boosting module cooperates with the dragging torque of the main motor of the whole vehicle according to the detected displacement signal of the plunger 2 to jointly realize braking. In the embodiment shown in fig. 8, the power assisting motor is not operated, the main shaft 21 is not moved and the output push rod 5 is not moved, therefore, the brake power assisting device only records and outputs displacement information of the plunger 2 or the input rod 1, at this time, the whole vehicle is braked by means of the dragging torque of the main motor, and the kinetic energy of the whole vehicle is converted into electric energy through a specific device and is fed back to the energy storage device, so that energy recovery is realized.

With continued reference to fig. 8 and 9, as the brake pedal is further pressed in the situation of fig. 8, the disc springs of the disc spring assembly 87 are sequentially deformed until the state shown in fig. 9, at which time the deformation of the disc spring assembly 87 reaches the maximum value, in the process, the reaction force generated by the joint deformation of the initial power spring 23 and the disc spring assembly 87 is transmitted to the brake pedal through the plunger 2 and the input rod 1, and then the displacement of the input rod 1 is combined, so as to form a second stage pedal feeling, which corresponds to the section B in fig. 12, and the section B with different strokes, for example, about 7-12mm, can be set according to the requirements of different vehicle models or the whole vehicle; the disc spring assembly 87 may be formed by sequentially stacking one or more disc springs, and the sequential deformation of a plurality of disc springs (e.g., two, three or four disc springs) can make the pedal feel corresponding to the stroke smoother and closer to the desired pedal feel curve. In the process, the working logic of the control unit is consistent with that in the process from fig. 7 to fig. 8, that is, whether the brake boosting module works or not is determined according to the current vehicle speed and the detected displacement signal of the plunger 2, if the drag torque of the main motor of the whole vehicle can meet the braking requirement under the current vehicle speed, the brake boosting module does not work, that is, the brake boosting motor 28 does not work, the output push rod 5 does not move along with the axial displacement of the plunger 2, that is, the displacement of the pedal does not cause the output push rod 5 to output the braking force; if the dragging torque of the main motor of the whole vehicle cannot meet the braking requirement at the current vehicle speed, the brake power-assisted module quickly responds to the displacement signal of the plunger 2 to start working, namely the brake power-assisted motor starts to output the torque, the output push rod 5 can move along with the axial displacement of the plunger 2 under the driving of the motor, so that the brake main cylinder is pushed to build pressure, and the brake power-assisted module and the dragging torque of the main motor of the whole vehicle work cooperatively according to the detected displacement signal of the plunger 2 to jointly realize braking. In the embodiment shown in fig. 9, the assisting motor works to push the output push rod 5 to move, in the process, the control unit controls the brake assisting module to quickly respond to the displacement signal of the plunger 2 to start working according to the current vehicle speed and the displacement signal of the plunger 2, under the driving of the control unit, the assisting motor starts to generate torque, the torque is amplified by the gear transmission mechanism and is transmitted to the spindle nut 24, the spindle 21 and the spindle nut 24 are combined through threads, so that the torque is transmitted to the spindle 21 through the spindle nut 24, and the rotational motion of the spindle 21 is restricted due to the fixed connection between the spindle 21 and the anti-rotating plate 91, so that the spindle 21 and the anti-rotating plate 91 jointly move along the axis to the direction of the brake master cylinder under the combined action of the torque and the threads, and further, the support piece 25, the return spring retainer 59 and the output push rod 5 jointly move along the axis to the direction of the brake master cylinder 50, so as to push the brake master cylinder to build pressure. The two ends of the rotation-preventing plate 91 are respectively sleeved on the pair of penetrating rods 9 through the sliding sleeves and cannot rotate, so that when the main shaft 21 moves leftwards, the rotation-preventing plate 91 also moves leftwards along the penetration-preventing rods 9 along with the rotation-preventing plate. In the process, the support plate 6 remains at a distance from the return spring holder 59, i.e. does not touch it.

With continued reference to fig. 9, 10 and 11, further depression of the brake pedal on the basis of fig. 9 will cause the plunger 2 to push the movement of the support plate 6 along the axial guide rod 7, thereby compressing the first and second pedal feel analog springs 82,83 on the axial guide rod 7. In the illustrated embodiment, the spacer 72 is in a convex shape, the spacer 72 has a flat portion 721, the flat portion 721 is engaged with the support plate 6 after the first pedal feel analog spring 82 is compressed, and the first pedal feel analog spring 82 may have a rigidity greater than that of the second pedal feel analog spring 83. As shown in fig. 10, the first pedal feel analog spring 82 and the second pedal feel analog spring 83 are compressed together due to the series connection. Referring to fig. 11, the second pedal feel analog spring 83 is compressed such that the flat portion 721 of the spacer 72 has engaged the support plate 6, and the second pedal feel analog spring 83 will not be compressed any more in the stroke thereafter. In the process, the reaction force generated by the deformation of the power spring 23, the disc spring assembly 87, the first pedal feeling simulation spring 82 and the second pedal feeling simulation spring 83 is transmitted to the brake pedal through the plunger 2 and the input rod 1, and then the displacement of the input rod 1 is combined, so that a third pedal feeling is formed, the pedal stroke of the third pedal feeling corresponds to the section C in the curve of FIG. 12, and the section C with different strokes can be set according to the requirements of different vehicle types or whole vehicles, for example, about 5-18mm. In the travel, the vehicle speed is reduced to the safe vehicle speed in a short time by a large deceleration, and in order to ensure the driving safety, the brake can be completely carried out by a brake assisting module instead of the dragging torque of the main motor of the whole vehicle in the process; in the process, the control unit controls the brake boosting module to quickly respond to the displacement signal of the plunger 2 to start working according to the current vehicle speed and the displacement signal of the plunger 2, and under the driving of the control unit, the boosting motor works and pushes the output push rod 5 to move towards the brake master cylinder 50 along the axis in the same way as described previously, so that the brake master cylinder is pushed to build pressure, and the brake is further realized.

Finally, referring to fig. 10 and 11, continued depression of the brake pedal on the basis of fig. 10 will cause the first pedal feel analog spring 82 to continue to be compressed. In this process, the reaction force generated by the deformation of the power spring 23, the disc spring assembly 87, the first pedal feeling simulation spring 82 and the second pedal feeling simulation spring 83 is transmitted to the brake pedal through the plunger 2 and the input rod 1, and then the displacement of the input rod 1 is combined, so as to form a fourth pedal feeling, the pedal stroke of the fourth pedal feeling corresponds to the section D in the curve of fig. 12, and the section D with different strokes, for example, about 3mm, can be set according to the requirements of different vehicle types or whole vehicles, because the stiffness coefficient of the first pedal feeling simulation spring 82 is greater than that of the second pedal feeling simulation spring 83, the slope of the section D is greater than that of the section C. In the travel, the vehicle speed is reduced to the safe vehicle speed in a short time by a large deceleration, and in order to ensure the driving safety, the brake can be completely carried out by a brake assisting module instead of the dragging torque of the main motor of the whole vehicle in the process; in the process, the control unit controls the brake boosting module to quickly respond to the displacement signal of the plunger 2 to start working according to the current vehicle speed and the displacement signal of the plunger 2, and under the driving of the control unit, the boosting motor works and pushes the output push rod 5 to move towards the direction of the brake master cylinder along the axis together in the same way as the previously described way, so that the brake master cylinder is pushed to build pressure, and the brake is further realized.

Finally, when the brake pedal is released, each spring of the pedal simulator module is restored to the initial state by means of the elasticity of the spring, and meanwhile, each part is pushed back to the initial state; at the same time, under the action of the elastic force of the return spring 58, the various parts of the brake boosting module are also pushed back to the initial state.

Therefore, the feedback curve of the theoretical pedal stroke and the pedal force, i.e. the pedal feel curve, as shown in fig. 12 can be realized by the decoupled brake boosting device of the embodiment shown in fig. 1 to 11.

On the other hand, in the decoupled brake boosting device and other brake boosting devices of the embodiment, when the brake pedal is stepped down under the conditions of power failure, failure of the boosting motor or other boosting failures, the boosting motor does not drive the output push rod 5 to move, at this time, the input rod 1 and the plunger 2 overcome the elastic forces of the initial power spring 23 and the disc spring assembly 87 and abut against the support plate 6, so that the support plate 6 is pushed to be directly engaged with the return spring retainer 59 on the back side of the output push rod 5, and then the output push rod 5 is directly pushed to move towards the brake master cylinder along the axis after overcoming the elastic forces of the pedal feeling simulation spring 82 and the pedal feeling simulation spring 83, so that the brake master cylinder is pushed to build pressure, and braking is further realized. This arrangement makes it possible to prevent braking from being possible by the driver depressing the brake pedal even in the event of a brake assistance failure, such as a power failure or a malfunction of the assistance motor.

A modification of the embodiment according to the invention will be described with continued reference to fig. 13. In the modification, a disc spring 871 in the disc spring assembly 87 is brought into contact with the support plate 6 in an initial state, thereby providing a first stage pedal feeling by replacing the power spring 23 by the disc spring 871. A modification of the embodiment according to the present invention will be described with continued reference to fig. 14. In this modification, a coil spring 88 between the back plate 6 and the plunger 2 is employed instead of the disc spring assembly 87 and the power spring 23, whereby the first stage and second stage pedal feeling are provided by the coil spring 88.

With continued reference to fig. 15 and 18, a decoupled brake boosting apparatus according to another embodiment of the embodiments will be described. In fig. 15, a displacement sensor assembly 99 is shown, which is located radially outside the plunger 2. As can be seen more clearly in fig. 18, in this embodiment, the disc spring assembly 87 is eliminated, and the spring 81 between the stop ring 71 and the support plate 6 on the axial guide rod 7 is used as the initial power spring, the initial power spring 81 is respectively sleeved outside the pedal feel simulation spring 82 and the pedal feel simulation spring 83, the inner end of the plunger 2 is directly and fixedly connected with the magnet bracket, and the side of the magnet bracket close to the brake master cylinder abuts against the support plate 6. Further, in this embodiment, the axial guide rod 7 has thereon the stopper ring 71 spaced apart from the support plate 6, the start power spring 81 is constructed between the stopper ring 71 and the support plate 6, and the radially inner side of the start power spring 81 is provided with the first pedal feel simulation spring 82 and the second pedal feel simulation spring 83, wherein the first end (left end) of the first pedal feel simulation spring 82 is connected to the stopper ring 71, the second end (right end) of the first pedal feel simulation spring 82 is connected to the first boss 74, the first end of the second pedal feel simulation spring 83 is connected to the first boss 74, and the second end (right end) of the second pedal feel simulation spring 83 is connected to the second boss 75. In the case where the brake pedal is not depressed, the support plate 6, the second boss 75, the first boss 74 and the stopper ring 71 are spaced apart. In this configuration, there is a gap between the back side 51 of the output ram 5 and the support plate 6. When the brake pedal is stepped on, the starting force spring 81 is first compressed until the support plate 6 comes into contact with the second boss 75, then the first pedal feel simulation spring 82 and the second pedal feel simulation spring 83 are compressed until the second boss 75 engages with the first boss 74, and finally the second pedal feel simulation spring 83 is no longer compressed and the first pedal feel simulation spring 82 is compressed. This configuration can also provide a theoretical pedal stroke and pedal force feedback curve, i.e., a pedal feel curve, as shown in fig. 12, wherein the curve includes three segments corresponding to the power spring 81, the second pedal feel analog spring 83, and the first pedal feel analog spring 82. According to the decoupled brake boosting device of the present embodiment, the brake boosting module is the same as the brake boosting module of the first embodiment, and the operation mode and the operation logic of the decoupled brake boosting device at each stage are also the same as the brake boosting module of the first embodiment.

A modification of the brake boosting device according to the present invention will be described with continued reference to fig. 19. The first pedal feeling simulation spring 82 and the second pedal feeling simulation spring 83 are replaced by a plurality of disc springs 891 connected in series, a first end of the plurality of disc springs 891 connected in series is connected to the baffle ring 71, a second end of the plurality of disc springs 891 connected in series is connected to the movable baffle ring 76, and the plurality of disc springs 891 connected in series are compressed after the shaft sleeve of the supporting plate contacts the movable baffle ring 76 so as to simulate various pedal feeling curves.

Referring again to fig. 20 and 22, a decoupled brake boosting device according to another embodiment of the embodiment will be described. In this embodiment, unlike the foregoing embodiment in which the support plate 6 and the pedal feel simulation springs 81, 82, and 83 are respectively fitted over the axial guide rod 7 that is parallel to the penetrating rod 9 and is circumferentially offset, in this embodiment, the support plate 6 and the pedal feel simulation springs 81, 82, and 83 are respectively fitted over the axial guide rod 7, that is, the support plate 6 and the rotation prevention disc 9 share the axial guide rod 7, the support plate 6 is located between the rotation prevention plate 91 and the brake master cylinder, and the support member 25 is located between the rotation prevention plate 91 and the support plate 6. This configuration can also provide a theoretical pedal stroke and pedal force feedback curve, i.e., a pedal feel curve, as shown in fig. 12, wherein the curve includes three segments corresponding to the power spring 81, the second pedal feel analog spring 83, and the first pedal feel analog spring 82. According to the decoupled brake boosting device of the embodiment, the brake boosting module is the same as that of the first embodiment, and the working modes and working logics of the brake boosting module at each stage are also the same as those of the first embodiment

According to another aspect of the embodiments, there is also provided a new energy vehicle, especially an electric vehicle, including the brake booster according to each embodiment, in the new energy vehicle, especially the electric vehicle, during a decoupling stroke of the brake booster, a control unit determines whether a brake booster module is operated according to a current vehicle speed and a detected displacement signal of a brake pedal, if a drag torque of a main motor of the whole vehicle can meet a braking demand at the current vehicle speed, the brake booster module is not operated, that is, the brake booster motor will not operate, an output push rod will not move along with an axial displacement of the brake pedal, that is, the displacement of the pedal will not cause the output push rod to output a braking force; if the dragging torque of the main motor of the whole vehicle can not meet the braking requirement at the current vehicle speed, the brake boosting module quickly responds to a displacement signal of the brake pedal to start working, namely the brake boosting motor starts to output the torque, the output push rod can move along with the axial displacement of the brake pedal under the driving of the motor so as to push the brake main cylinder to build pressure, and the brake boosting module and the dragging torque of the main motor of the whole vehicle cooperate to realize braking together according to the detected displacement signal of the brake pedal; under the coupling working mode or when the set whole vehicle energy recovery condition is exceeded, the whole vehicle main motor does not participate in braking, the control unit controls the work of the brake power-assisted module according to the current vehicle speed and the detected displacement of the brake pedal, and the output push rod moves along with the axial displacement of the brake pedal under the driving of the motor, so that the brake main cylinder is pushed to build pressure, and the whole vehicle braking is finally realized;

it should be understood that the decoupled brake booster of an embodiment may be installed on a variety of vehicles, including gasoline vehicles, diesel vehicles, passenger cars, trucks, buses, hybrid vehicles, electric vehicles, and the like. In particular, the decoupling type brake booster can be used for a new energy automobile with a main motor of the whole automobile. In addition, in the case of application to a diesel locomotive, the decoupled brake booster can be operated in the manner of an electronic control device, i.e. in the event of detection of the intention of the driver to brake, as a controller, to send a brake signal to the vehicle brake system, so that a braking action is carried out in real time.

The decoupled type is that when the input rod of the pedal feel simulator moves toward the master cylinder, the support plate and the output push rod can be coupled and decoupled, that is, can be in contact with or not in contact with each other. Under the condition of non-contact, the whole brake booster brakes in a mode, for example, the brake can be realized by singly depending on the dragging torque of the main motor of the whole vehicle, and the brake can also be realized by the cooperation of a hydraulic brake main cylinder and the brake boosting and the dragging torque of the main motor of the whole vehicle; in the case of contact, the whole brake booster performs braking in another mode, for example, the brake booster can be cooperated with the brake boosting by a hydraulic brake main cylinder to realize braking together with the dragging torque of the main motor of the whole vehicle, or the brake booster can be cooperated with the brake boosting by the hydraulic main brake cylinder to realize braking without the dragging torque of the main motor. Since the emphasis here is on the pedal travel sensor module, the elastomer, the overall dimensions of the booster and the design of the spindle nut bearing, little description is given about the other components of the decoupled brake booster, including its operating principle.

It should be appreciated that the power spring, the pedal feel simulation spring, the size, shape, stiffness coefficient of the disc spring assembly, pitch of the spring, wire diameter, plate thickness, inner diameter, material, arrangement (e.g., in series or in parallel), etc. may all affect the characteristic curve of the entire pedal feel simulation mechanism. The desired parameters and characteristics may be obtained through experience, experimentation, and user feedback.

The foregoing description of the specific embodiments has been provided merely to more clearly illustrate the principles of the embodiments, and to clearly show or describe various components therein so that the same may be better understood. Various modifications or changes to the embodiments may be readily made by those skilled in the art without departing from the scope of the embodiments. It is to be understood that such modifications and variations are intended to be included within the scope of the appended claims.

Claims (10)

1. A decoupled brake assist device comprising:

the brake system comprises an input rod (1), wherein the input rod (1) is used for being connected with a brake pedal;

the plunger (2) is connected with the input rod (1), and when the brake pedal is stepped on, the input rod (1) drives the plunger (2) to move axially;

a displacement sensor assembly that senses axial displacement of the input rod (1) or the plunger (2);

a power-assisted motor and control unit (28) which controls the power-assisted motor to operate to output a brake power-assisted torque;

an output push rod (5), the output push rod (5) being operatively coupled with the power-assist motor to receive the brake-assist torque and perform an axial displacement to output a braking force to a brake cylinder (50);

characterized in that, the brake booster unit still includes: a pedal feel simulation device comprising:

an axial guide rod (7) located radially outside the plunger (2);

the outer side (62) of the support plate (6) is sleeved on the axial guide rod (7), and when the plunger (2) is in contact with the middle part (61) of the support plate (6), the support plate (6) is pushed by the plunger (2) to move towards the direction of the brake master cylinder together; and

a pedal feel simulation spring provided on the axial guide rod (7) and abutting against the support plate (6) to apply a reaction force to the support plate (6).

2. Decoupled brake booster according to claim 1, characterized in that the plunger (2) is spaced apart from the support plate (6) in an initial state in which the brake pedal is not depressed, the end (26) of the plunger (2) being provided with a laminated spring assembly (87), optionally one of the laminated springs (871) of the laminated spring assembly (87) contacting the support plate (6).

3. Decoupled brake boosting device according to claim 1, characterized in that in an initial state in which the brake pedal is not depressed, the plunger (2) is spaced apart from the back plate (6), a coil spring (88) being provided between the end (26) of the plunger (2) and the back plate (6).

4. The decoupled brake booster according to claim 1, 2 or 3, characterized in that the axial guide rod (7) has a stop ring (71) spaced apart from the support plate (6), a spacer (72) is provided between the stop ring (71) and the support plate (6) and is fitted over the axial guide rod (7), a first pedal feel simulation spring (82) is provided between the spacer (72) and the stop ring (71), a second pedal feel simulation spring (83) is provided between the spacer (72) and the support plate (6), wherein the spacer (72) is convex, the spacer has a flat portion (721), the flat portion (721) engages with the support plate (6) after the second pedal feel simulation spring (83) is compressed, and the first pedal feel simulation spring (82) has a stiffness greater than the second pedal feel simulation spring (83).

5. Decoupled brake booster according to claim 1, characterized in that the axial guide rod (7) has a stop ring (71) spaced apart from the support plate (6), a starting force spring (81) is provided between the stop ring (71) and the support plate (6), a plurality of disk springs (891) connected in series being arranged radially inside the starting force spring (81), or

The radial inner side of the starting power spring (81) is provided with a first pedal feeling simulation spring (82) and a second pedal feeling simulation spring (83), the first end of the first pedal feeling simulation spring (82) is connected to the stop ring (71), the second end of the first pedal feeling simulation spring (82) is connected to a first shaft sleeve (74) sleeved on the axial guide rod (7), the first end of the second pedal feeling simulation spring (83) is connected to a first shaft sleeve (74), the second end of the second pedal feeling simulation spring (83) is connected to a second shaft sleeve (75) sleeved on the axial guide rod (7), the first shaft sleeve (74) and the second shaft sleeve (75) can slide along the axial guide rod (7), and in an initial state that the pedal is not pressed, the support plate (6), the second shaft sleeve (75), the first shaft sleeve (74) and the stop ring (71) are spaced apart.

6. The brake boosting device according to claim 1, wherein a spindle (21) is disposed on an outer ring of the plunger (2), a spindle nut (24) is disposed on an outer ring of the spindle (21), the spindle (21) is in threaded engagement with the spindle nut (24), an inner end of the spindle (21) is fixedly connected with a middle portion of an anti-rotation plate (91), an outer side of the anti-rotation plate (91) is sleeved on the through rod (9) or the axial guide rod (7), so that rotation of the anti-rotation plate (91) and the spindle (21) is limited, the power-assisted motor drives the spindle nut (24) to rotate via a reduction gear set, the spindle nut (24) drives the spindle (21) to axially move in a direction of a brake master cylinder by means of threaded engagement with the spindle (21), a support member (25) is disposed on a side of the anti-rotation plate (91) close to the brake master cylinder, a first end of the support member (25) is fixedly connected with the anti-rotation plate (91), a second end of the support member (25) is fixedly connected with a return spring (59), and the retainer (59) supports the return spring (5).

7. Decoupled brake boosting device according to claim 6, characterized in that a start power spring (23) is arranged between the spindle (21) and the input rod (1).

8. The brake servo unit according to claim 6, wherein the support member (25) comprises a pair of support blocks symmetrically disposed at both sides of the plunger (2) with a gap therebetween, the plunger (2), a disc spring assembly (87) or a coil spring (88) at an end of the plunger (2), and a middle portion (61) of the support plate are located in the gap between the pair of support blocks, and a sensor bracket (93) connected to the plunger (2) extends from the gap.

9. The brake servo system according to claim 1, wherein the back side of the output push rod (5) is provided with a return spring holder (59), the support plate (6) is positioned between the plunger (2) and the return spring holder (59), in case of failure of a booster motor or failure of a brake servo module, the plunger (2) directly pushes the support plate (6) to engage with the return spring holder (59) on the back side of the output push rod (5) when the brake pedal is depressed, and the movement of the support plate (6) directly drives the output push rod (5) to axially move, thereby outputting braking force to a brake cylinder.

10. Vehicle, in particular electric vehicle, comprising a decoupled brake booster according to one of claims 1 to 9, characterized in that the decoupled brake booster has both decoupled and non-decoupled modes of operation in the vehicle:

when the travel of the brake pedal is smaller than the decoupling distance, a control unit of the decoupling type brake power assisting device determines whether a brake power assisting motor works or not according to the current vehicle speed and the detected pedal travel, if the dragging torque of the main motor of the whole vehicle can meet the braking requirement under the current vehicle speed, the brake power assisting motor does not work, and the braking is realized by the dragging torque of the main motor of the whole vehicle; if the dragging torque of the main motor of the whole vehicle cannot meet the braking requirement at the current vehicle speed, the brake power-assisted motor starts to work in response to the displacement signal of the plunger (2) so as to realize braking in cooperation with the dragging torque of the main motor of the whole vehicle;

when the travel of the brake pedal is larger than or equal to the decoupling distance, the control unit controls the brake power-assisted motor to work according to the current vehicle speed and the detected displacement of the plunger (2), so that the brake master cylinder is pushed to build pressure.

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