CN110920584A

CN110920584A - Asynchronous reset brake booster capable of automatically and emergently braking during blocking

Info

Publication number: CN110920584A
Application number: CN201911395946.1A
Authority: CN
Inventors: 潘亚敏; 韩星
Original assignee: Shanxi Guoli Information Technology Co Ltd
Current assignee: Shanxi Guoli Information Technology Co Ltd
Priority date: 2019-12-30
Filing date: 2019-12-30
Publication date: 2020-03-27

Abstract

In order to solve the technical problem that the conventional brake booster with the retardation recognition function has potential safety hazards, the invention provides an asynchronous reset brake booster capable of automatically and emergently braking during retardation. The improvement of the invention is as follows: the guide rail assembly is arranged on the side wall of the shell; the pedal force transmission rod is axially clamped with the pedal force transmission plate, and the pedal force transmission rod and the pedal force transmission plate can be separated at the clamping position under the condition of external force retardation only during automatic emergency braking; or the pedal force transmission rod is only contacted with and not connected with the pedal force transmission plate in the axial direction; the bracket assembly comprises a pedal force bracket and an electric power bracket; the pedal force disappears, the electric power support firstly begins to reset under the action of the second group of reset springs, and then the pedal force support is driven by the first group of reset springs to carry out follow-up reset. During the automatic emergency braking, the automatic emergency braking system can quickly respond to the operation of interrupting the automatic emergency braking by a driver, and meets the requirement of the state on the intervention performance of the driver of the automatic emergency braking system of the passenger vehicle.

Description

Asynchronous reset brake booster capable of automatically and emergently braking during blocking

Technical Field

The invention relates to an automatic emergency brake booster for a vehicle, in particular to an asynchronous reset brake booster capable of automatically and emergently braking when in retardation.

Background

A conventional vehicle brake booster includes a housing, a pedal force input unit, an electric power generating unit, a supporting and guiding unit, a returning unit, a pedal force transmitting unit, an electric power transmitting unit, and a braking force output unit; a pedal force input unit for receiving a pedal force from a driver; an electromotive force generating unit for generating electromotive force; the supporting and guiding unit is used for supporting the pedal force transmission unit and the electric power transmission unit in the shell and ensuring that the pedal force transmission unit and the electric power transmission unit can only move along the axial direction; the resetting unit is used for resetting the pedal force transmission unit and the electric power transmission unit; the pedal force transmission unit is used for transmitting the pedal force to the braking force output unit; the electric power transmission unit is used for transmitting electric power to the braking force output unit; the braking force output unit is used for loading the pedal force output by the pedal force input unit and/or the electric power output by the electric power generation unit on the master cylinder.

Patent publication No. CN 108025728A discloses a brake booster, in which a spindle (also called an electric push rod) is supported on a carrier element (also called a guide rod) by a support device, and the spindle is translatable along the carrier element by means of the support device, so that an electric brake force output by a motor of the brake booster is transmitted to a master brake cylinder (also called a master cylinder) by translation of the electric push rod. The disadvantages of such a brake booster are:

1. when the bearing element (also called a guide rod) is assembled, the consistency of bolt tightening torque is difficult to ensure, so that the assembly consistency of the guide rod cannot be ensured, and the reliability of the whole product is influenced.

2. The number of parts which need to be processed and assembled separately is large, and the production and assembly efficiency is low.

At present, on the basis of the above conventional vehicle brake booster, a brake booster with a blocking recognition function is also designed, which is based on the principle that when the brake pedal is blocked by a foreign object or the driver's foot accidentally sticks into the bottom of the brake pedal and is clamped in an automatic braking mode, the control part of the electromotive force generating unit recognizes that the brake pedal is blocked and stops generating the electromotive force continuously to stop braking, so as to achieve the purpose of preventing the brake system components from being damaged by the strong foreign object and preventing the driver's foot from being injured by the pinching, such as the brake booster disclosed in patent documents with publication numbers CN 109131270a and CN 107949507 a.

However, the above brake booster carries a risk that when the mechanism recognizes that the brake pedal is blocked, the continuation of braking will be stopped, which at the time of crisis will result in the vehicle hitting an obstacle ahead, and even in the injury or death of the vehicle occupant or pedestrian.

In addition, when the conventional brake booster is reset, the pedal force transmission unit and the electric power transmission unit are reset simultaneously, when a motor of the electric power generation unit breaks down, a driver can only manually tread a brake pedal to brake, and at the moment, large force is needed, so that the burden of the driver is increased.

Disclosure of Invention

In order to solve the technical problem that the conventional brake booster with the retardation recognition function has potential safety hazards, the invention provides an asynchronous reset brake booster capable of automatically and emergently braking during retardation.

The technical scheme of the invention is as follows:

an asynchronous reset brake booster capable of automatically and emergently braking during blocking comprises

The brake system comprises a shell, a pedal force input unit, an electric power generating unit, a supporting and guiding unit, a resetting unit, a pedal force transmission unit, an electric power transmission unit and a braking force output unit;

the supporting and guiding unit comprises a bracket assembly and a guide rail assembly;

the pedal force transmission unit comprises a pedal force transmission rod and a pedal force transmission plate; an anti-rotation triggering column is arranged on the pedal force transmission plate;

it is characterized in that:

the guide rail assembly is arranged on the side wall of the shell and is integrally formed with the shell;

the pedal force transmission rod is axially clamped with the pedal force transmission plate, and the pedal force transmission rod and the pedal force transmission plate can be separated at the clamping position under the condition of external force retardation only during automatic emergency braking; or the pedal force transmission rod and the pedal force transmission plate are axially arranged in sequence and are only contacted and not connected;

the bracket assembly comprises a pedal force bracket and an electric power bracket;

the reset unit comprises a first group of reset springs and a second group of reset springs;

when the pedal force disappears, the electric power support firstly starts to reset under the action of the second group of return springs, and then the pedal force support is driven by the first group of return springs to carry out follow-up reset.

Further, when the pedal force transmission rod is axially clamped with the pedal force transmission plate, the clamping form of the two brackets is columnar clamping or spherical clamping.

Further, the bracket assembly further comprises a pedal force guide element and an electric force guide element; the pedal force bracket comprises a pedal push rod and at least one pedal force bracket arm connected with the pedal push rod; the pedal force guide element is arranged at the end part of the pedal force bracket arm; the electric power support comprises an electric push rod and at least one electric power support arm connected with the electric push rod; the electrodynamic guide element is arranged at the end of the electrodynamic support arm; the pedal push rod and the electric push rod are both of tubular structures with openings at two ends, the pedal push rod is arranged in the electric push rod, and the pedal push rod and the electric push rod are in clearance fit and can move relatively along the axial direction; the guide rail assembly comprises a guide rail which is an inner and/or outer guide structure; the pedal force bracket arm is in sliding connection with the guide rail through a pedal force guide element; the electrodynamic force support arm is in sliding connection with the guide rail through an electrodynamic force guide element; the pedal force transmission rod is arranged in the pedal push rod; the pedal force transmission plate is characterized in that a first guide hole is formed in the pedal force support arm, a second guide hole is formed in the electric power support arm, and an anti-rotation trigger column on the pedal force transmission plate sequentially penetrates through the first guide hole and the second guide hole.

Further, the guide rail is a guide pillar with a concave, C-shaped or omega-shaped section; the first group of return springs are arranged on a central axis of the brake booster, and the second group of return springs are arranged in the guide rail.

Further, the first group of return springs borrow vehicle brake master cylinder return springs.

Or the guide rail is a guide pillar with a concave, C-shaped or omega-shaped section; the pedal force guide element is matched with the outer wall of the guide rail to realize external guide; the electric force guiding element is matched with the inner wall of the guide rail to realize internal guiding; the second group of return springs are electrodynamic force support return springs, one end of each electrodynamic force support return spring is in contact with or connected with the shell of the brake booster, and the other end of each electrodynamic force support return spring is in contact with or connected with the electrodynamic force guide element.

Alternatively, the bracket assembly further comprises a pedal force guide member and an electric force guide member; the pedal force bracket comprises a pedal push rod and at least one pedal force bracket arm connected with the pedal push rod; the pedal force guide element is arranged at the end part of the pedal force bracket arm; the electric power support comprises an electric push rod and at least one electric power support arm connected with the electric push rod; the electrodynamic force guide element is arranged at the end part of the electrodynamic force bracket arm; the pedal push rod and the electric push rod are both of tubular structures with openings at two ends, and the pedal push rod is arranged in the electric push rod and is in clearance fit with the electric push rod and can move relatively along the axial direction; the guide rail assembly comprises a pedal force guide rail and an electric power guide rail, and the pedal force guide rail and the electric power guide rail are of inner and/or outer guide structures; the pedal force bracket arm is connected with the pedal force guide rail in a sliding way through a pedal force guide element; the electrodynamic force support arm is in sliding connection with the electrodynamic force guide rail through an electrodynamic force guide element; the pedal force transmission rod is arranged in the pedal push rod; a first guide hole is formed in the pedal force support arm, a second guide hole is formed in the electric power support arm, and the anti-rotation triggering column on the pedal force transmission plate sequentially penetrates through the first guide hole and the second guide hole.

Further, the electric power guide rail is a guide pillar with a concave, C-shaped or omega-shaped section; the electric force guiding element is matched with the inner surface of the electric force guide rail to realize internal guiding; the second group of return springs are arranged in the electric power guide rail, one end of each second group of return springs is in contact with or connected with the shell of the brake booster, and the other end of each second group of return springs is in contact with or connected with the electric power guide element; the first group of springs is a vehicle brake master cylinder return spring.

Or the electric power guide rail and the pedal force guide rail are guide columns with concave, C-shaped or omega-shaped sections; the electric power guide element and the pedal force guide element are respectively matched with the inner surfaces of the electric power guide rail and the pedal force guide rail to realize internal guide; the second group of return springs are arranged in the electric power guide rail, one end of each second group of return springs is in contact with or connected with the shell of the brake booster, and the other end of each second group of return springs is in contact with or connected with the electric power guide element; the first group of return springs are arranged in the pedal force guide rail, one ends of the first group of return springs are in contact with or connected with the shell of the brake booster, and the other ends of the first group of return springs are in contact with or connected with the pedal force guide element.

Further, the end part of the pedal force transmission rod close to the braking force output unit is provided with a pedal elastic element; an electric following stroke is formed between the pedal elastic element and the braking force output unit; the electric following stroke is an idle stroke or a micro-force stroke.

Furthermore, the pedal elastic element comprises a first elastic body and a second elastic body which are sequentially arranged along the transmission direction of the braking force, one end of the second elastic body is connected with the first elastic body, and the other end of the second elastic body is contacted with the braking force output unit; the elastic coefficients of the first elastic body and the second elastic body are different.

Further, the electric power transmission unit comprises a transmission gear nut, an external thread arranged on the outer wall of the electric push rod, a power-assisted pushing piece and an electric elastic element; the transmission gear nut is composed of a nut with internal threads and a transmission gear with external transmission teeth, the transmission gear is arranged outside the nut, the nut is sleeved outside the electric push rod and is connected with the external threads through the internal threads to drive the electric push rod to move along the axial direction; the boosting push piece is arranged between the pedal force bracket and the braking force output unit; the boosting push piece is integrally bowl-shaped, one end of the boosting push piece is connected with a pedal force support arm of the pedal force support, and the other end of the boosting push piece is contacted with the braking force output unit; the bottom of the power-assisted pushing piece is provided with a through hole for the elastic element of the pedal to pass through; the electric elastic element is arranged between the pedal force bracket and the electric power bracket; the electric elastic element is of an integrated annular structure or a split structure consisting of a plurality of elastic bodies which are uniformly distributed along the circumference; the elastic coefficients of the electric elastic element and the pedal elastic element can be the same or different.

Or the electric power transmission unit comprises a transmission gear nut with internal threads and external transmission teeth, external threads arranged on the outer wall of the electric push rod, an assistance push piece and an electric elastic element; the transmission gear nut is sleeved outside the electric push rod and is connected with the external thread through the internal thread to drive the electric push rod to move along the axial direction; the boosting push piece is arranged between the pedal force bracket and the braking force output unit; the boosting push piece is integrally bowl-shaped, one end of the boosting push piece is connected with a pedal force support arm of the pedal force support, and the other end of the boosting push piece is contacted with the braking force output unit; the bottom of the power-assisted pushing piece is provided with a through hole for the elastic element of the pedal to pass through; the electric elastic element is arranged in the boosting push piece and is positioned between the pedal elastic element and the braking force output unit; the electric elastic element is of an integrated annular structure or a split structure consisting of a plurality of elastic bodies which are uniformly distributed along the circumference; under the action of pedal force and/or electric force, the pedal elastic element can pass through the electric elastic element to transmit braking force to the braking force output unit; the elastic coefficients of the electric elastic element and the pedal elastic element can be the same or different.

Furthermore, one or more support structures are arranged between the upper end face and the lower end face of the housing, which support structures are used for fixing a brake master cylinder of a vehicle, and at least one support structure can bear acting forces from the axial direction and/or the radial direction.

Further, the reset unit further comprises a pedal force return spring; the pedal force return spring is arranged outside the pedal force transmission rod and is positioned between the boosting push piece and the pedal force transmission plate; or the outer side wall of the pedal force input rod is provided with a limiting bulge, and the pedal force return spring is arranged between the limiting bulge and the pedal push rod.

The invention also provides another asynchronous reset brake booster capable of automatically and emergently braking during retardation, which comprises a shell, a pedal force input unit, an electric power generation unit, a supporting and guiding unit, a reset unit, a pedal force transmission unit, an electric power transmission unit and a brake force output unit; the supporting and guiding unit comprises a bracket assembly and a guide rail assembly; the pedal force transmission unit includes a pedal force transmission rod; it is characterized in that:

the pedal force transmission rod comprises a front section and a rear section which are coaxially clamped; only when the brake is automatically and emergently braked, the front section and the rear section can be separated at the clamping part under the external force retardation; or the pedal force transmission rod comprises a front section, a middle section and a rear section which are coaxially and sequentially clamped; only when the brake is automatically and emergently braked, the front section and the middle section or the middle section and the rear section can be separated from the clamping part under the condition of external force retardation;

Compared with the prior art, the invention has the advantages that:

1. the pedal force transmission rod and the pedal force transmission plate in the pedal force transmission unit are axially arranged in a split manner, and under an automatic emergency braking mode, when foreign matters or feet of a driver extend into the bottom of a brake pedal of a vehicle, the movement of the pedal force transmission rod is blocked, so that the pedal force transmission plate is separated from the pedal force transmission rod, and the condition that the feet of the driver are clamped due to the fact that the pedal force transmission rod continues to translate or brake system components are damaged due to the fact that the foreign matters are firm is avoided; meanwhile, in the automatic emergency braking mode, the pedal force transmission plate can still translate under the action of the electric power, so that the electric power transmission unit cannot be prevented from transmitting the electric power to the braking force output unit, the braking operation is implemented, and the potential safety hazard is avoided.

2. When the pedal force transmission rod is clamped with the pedal force transmission plate, no idle stroke exists between the pedal force transmission rod and the pedal force transmission plate, and the brake pedal feels better when a driver treads the brake pedal during normal braking.

3. When the pedal force transmission rod is clamped with the pedal force transmission plate, no idle stroke exists between the pedal force transmission rod and the pedal force transmission plate, the automatic emergency braking operation can be quickly interrupted by a driver during automatic emergency braking, and the national requirement that a passenger car Automatic Emergency Braking System (AEBS) has driver intervention performance is met.

4. The invention can be applied to the traditional brake booster, can realize the purposes of preventing the foot clamping and preventing the auxiliary brake system from being locally damaged due to the blocking of foreign matters by slightly changing the existing vehicle booster brake, can still implement the braking when the blocking occurs, and has low improvement cost.

5. The pedal force transmission rod and the pedal force transmission plate are clamped in a columnar manner, so that clamping and axial positioning can be realized.

6. The pedal force transmission rod in the pedal force transmission unit is of a two-section split structure consisting of a front section and a rear section, and under an automatic emergency braking mode, when foreign matters or feet of a driver extend into the bottom of a vehicle brake pedal, the front section is blocked in movement, so that the rear section is separated from the front section, and the condition that the feet of the driver are clamped due to continuous translation of the front section or brake system components are damaged due to firm foreign matters is avoided; meanwhile, in the automatic emergency braking mode, the rear section can still translate under the action of the electric power, so that the electric power transmission unit cannot be prevented from transmitting the electric power to the braking force output unit, the braking operation is implemented, and the potential safety hazard is avoided.

7. The pedal force transmission rod in the pedal force transmission unit is of a three-section split structure formed by coaxially clamping a front section, a middle section and a rear section, and under an automatic emergency braking mode, when foreign matters or feet of a driver extend into the bottom of a brake pedal, the movement of the front section or the middle section is blocked, so that the front section is separated from the middle section or the middle section is separated from the rear section, and the condition that the feet of the driver are clamped due to the fact that the front section continues to translate, or parts of a braking system are damaged due to the fact that the foreign matters are firm is avoided; meanwhile, the rear section can still translate under the action of the electric braking force, so that the electric power transmission unit cannot be prevented from transmitting the electric power to the braking force output unit, the braking operation is implemented, and the potential safety hazard is avoided; simultaneously, because footboard power transmission rod has two departments joint, if one of them department of joint extremely can not throw off when can not throw off because of corrosion etc. the card, can also throw off from another department, for two sections split type designs, the reliability of throwing off between each section of footboard power transmission rod when further having improved the footboard and blocking.

8. In the invention, the sections of the pedal force transmission rod are connected in a clamping manner, no idle stroke exists between the sections, and the brake pedal feels better when a driver treads the brake pedal during normal braking.

9. In the invention, the sections of the pedal force transmission rod are connected in a clamping manner, no idle stroke exists between the sections, the automatic emergency braking operation interrupted by a driver can be quickly responded during the automatic emergency braking, and the national requirement that an Automatic Emergency Braking System (AEBS) of a passenger vehicle has the driver intervention performance is met.

10. When the pedal force transmission rod and the pedal force transmission plate or all sections of the pedal force transmission rod are separated due to the blocking force during automatic emergency braking, the pedal force transmission rod can be easily clamped again in a manual pedal force applying mode after the blocking force disappears, and the pedal force transmission rod is not required to be maintained or influenced to be reused.

11. The guide rails are arranged on the side wall of the shell and are integrally formed with the shell, so that the consistency of the guide rails is effectively ensured, and the stability and reliability of the product are improved.

12. The shell can be manufactured by adopting a method of stretch forming, die-casting forming or injection molding, and has good consistency, high stability and low cost.

13. The invention provides a new idea of designing a single bracket of a vehicle brake booster into a double bracket, so that a pedal force bracket can be reset by a first group of reset springs, an electric power bracket is reset by a second group of reset springs, and when a motor of the vehicle brake booster breaks down, a driver does not need to overcome the elasticity of the reset springs of the electric power bracket during manual braking, so that the pedal force required to be applied is less than that of the prior art.

14. The electrodynamic force support and the pedal force support are reset asynchronously, the electrodynamic force support is reset firstly, and the pedal force support is reset in a following mode.

15. The elastic coefficient of the pedal elastic element and the elastic coefficient of the electric elastic element can be independently adjusted or respectively adjusted, so that the brake pedal can be adapted to brake pedal feeling of different types of vehicles, such as cars, saloon cars, sports cars (small elastic coefficient), SUVs and all-terrain vehicles (large elastic coefficient) in passenger vehicle types.

Drawings

Fig. 1 is a schematic view of the cooperation of embodiment 1 of the present invention with a vehicle master cylinder (electric power generating unit not shown).

FIG. 2 is a first perspective view (with the upper cover removed) of embodiment 1 of the present invention

Fig. 3 is a second perspective view (with the upper cover and the bottom case removed) of embodiment 1 of the present invention.

Fig. 4 is a three-dimensional view (another view angle) of embodiment 1 of the present invention.

Fig. 5 is a schematic view showing the combination of the pedal force bracket, the electric power bracket, and the pedal force transmission plate in embodiment 1 of the invention.

Fig. 6 is an exploded view of fig. 5.

Fig. 7 is a schematic view of the engagement between the transmission gear nut and the electric push rod in embodiment 1 of the present invention.

Fig. 8 is an exploded view of fig. 7.

Fig. 9 is a schematic view of the cooperation of the electromotive force generating unit and the electromotive force transmitting unit in embodiment 1 of the present invention.

Fig. 10 is a schematic structural view of an electromotive force carrier arm in embodiment 1 of the present invention.

Fig. 11 is a schematic view of the fitting relationship between the pedal force transmission plate and the pedal force transmission rod in embodiment 1 of the present invention.

Fig. 12 is a schematic view of the power-assisted pushing element and the connector in embodiment 1 of the invention.

Fig. 13 is a schematic view of the middle case and the bottom case engaged in embodiment 1 of the present invention.

Fig. 14 is an exploded view of a driving gear nut in embodiment 1 of the present invention.

Fig. 15 is a schematic diagram of a state of the clip to be separated according to embodiment 1 of the present invention.

Fig. 16 is a schematic view of the state of the separated clip legs in embodiment 1 of the present invention.

FIG. 17 is a schematic view of the mechanism in a stationary state in embodiment 1 of the present invention.

FIG. 18 is a schematic view showing a braking state of the mechanism in embodiment 1 of the present invention.

Fig. 19 is a schematic view showing the cooperation of embodiment 2 of the present invention with a vehicle master cylinder (electric power generating unit not shown).

Fig. 20 is a schematic view of the cooperation of embodiment 3 of the present invention with a vehicle master cylinder (electric power generating unit not shown).

Fig. 21 is a schematic diagram of the cooperation of embodiment 4 of the present invention with a vehicle master cylinder (electric power generating unit not shown).

Fig. 22 is a schematic view showing the cooperation of embodiment 5 of the present invention with a vehicle master cylinder (electric power generating unit not shown).

Fig. 23 is a schematic view showing the cooperation of embodiment 6 of the present invention with a vehicle master cylinder (electric power generating unit not shown).

Fig. 24 is a schematic view showing the cooperation of embodiment 7 of the present invention with a vehicle master cylinder (electric power generating unit not shown).

Fig. 25 is another implementation of the intermediate housing of the present invention.

Description of reference numerals:

1-pedal force input rod, 2-motor output gear, 3-intermediate gear set, 4-driving gear box, 41-screw box, 42-driving gear, 5-electric push rod, 51-external thread, 6-pedal push rod, 7-pedal force transmission rod, 71-front section, 72-rear section, 73-middle section, 74-circumferential groove, 75-cantilever structure, 711-spherical chuck, 721-claw type clamping groove, 8-pedal force transmission plate, 81-circumferential bulge, 82-central blind hole, 10-anti-rotation triggering column, 101-first carrier, 102-second carrier, 11-pedal force return spring, 12-electric power support, 120-electric power support arm, 121-second guide hole, 122-elastic accessory, 13-pedal force support, 130-pedal force support arm, 131-first guide hole, 14-electrodynamic guide element, 15-pedal force guide element, 17-booster, 171-through hole, 172-snap, 173-guide structure, 18-electrodynamic elastic element, 19-braking force output element A, 20-braking force output element B, 21-bearing bushing, 22-flanged steel plate, 23-bottom shell, 24-bearing, 25-booster fixing bolt, 26-middle shell, 261-bearing structure, 262-guide rail, 27-upper cover, 28-master cylinder, 29-master cylinder fixing bolt, 31-motor, 33-electrodynamic support return spring, 35-pedal elastic element, 36-induction magnet, 37-connector, 38-Hall sensor, 39-sensor fixing frame.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

Example 1:

the vehicle automatic emergency brake booster provided by the embodiment comprises a shell, a pedal force input unit, a pedal force transmission unit, a supporting and guiding unit, an electric power transmission unit, an electric power generation unit, a resetting unit and a braking force output unit.

As shown in fig. 1 to 4, the housing includes an upper cover 27, a middle housing 26 and a bottom shell 23 connected in sequence; a through hole for the columnar input end of the master cylinder 28 to pass through is formed in the middle of the upper cover 27, and four bearing structures 261 (in this embodiment, the bearing structures 261 are bolt fixing holes, and not only play a role of connection, but also can bear acting force) are arranged on the inner side wall of the middle shell 26; the brake master cylinder 28 is fixed on the middle shell 26 together with the upper cover 27 through the matching and fastening of the master cylinder fixing bolt 29 and the bearing structure 261; the bottom shell 23 is fixedly mounted on the vehicle through a booster fixing bolt 25; a connector 37 is also arranged in the bottom shell 23; a steel plate 22 is mounted on the bottom outside of the bottom case 23.

As shown in fig. 1, the pedal force input unit includes a pedal force input rod 1, and one end of the pedal force input rod 1 is connected to a brake pedal of the vehicle and the other end is connected to the pedal force transmission unit.

As shown in fig. 1, 6, 8, 9, the pedal force transmission unit includes a pedal force transmission rod 7 and a pedal force transmission plate 8; two end faces of the pedal force transfer plate 8 are respectively provided with a central blind hole, and the edge of the pedal force transfer plate 8 is provided with an anti-rotation triggering column 10; one end of the pedal force transmission rod 7 is connected with the output end of the pedal force input rod 1, and the other end of the pedal force transmission rod 7 is clamped with the pedal force transmission plate 8; the pedal force transmission rod 7 and the pedal force transmission plate 8 can be clamped in a spherical manner (namely a spherical clamping head and a claw-shaped clamping groove manner) or a columnar manner; in order to realize axial positioning during clamping, a columnar clamping mode is preferably adopted between the pedal force transmission rod 7 and the pedal force transmission plate 8, as shown in fig. 11, a plurality of cantilever structures 75 are formed on the end portion of the pedal force transmission rod 7 along an axial cutting groove, a circumferential groove 74 is formed on each cantilever structure 75, and correspondingly, a circumferential protrusion 81 which is matched with the circumferential groove 74 to realize axial clamping is arranged in a central blind hole 82 at one end of the pedal force transmission plate 8; of course, it is also possible to provide a circumferential projection on the cantilever structure 75 and a circumferential recess in the central blind hole 82. Only during automatic emergency braking, the pedal force transmission rod 7 and the pedal force transmission plate 8 can be disengaged at the engagement point under the external force retardation.

A pedal elastic element 35 is embedded in a central blind hole at the other end of the pedal force transmission rod plate 8, the pedal elastic element 35 can be made of elastic rubber, and other elastic elements such as a spring, a disc spring and the like can also be used; in the rest state, there is an axial idle stroke between the pedal spring element 35 and the input of the brake force output unit.

The supporting and guiding unit comprises a bracket assembly, a guide rail assembly and a bearing assembly;

as shown in fig. 3, 5-10, the bracket assembly in this embodiment includes a pedal force bracket 13, a pedal force guide member 15, an electromotive force bracket 12, and an electromotive force guide member 14; the guide rail assembly comprises two guide rails 262 which are parallel to each other and have C-shaped sections, and the guide rails 262 are arranged on the side wall of the middle shell 26 and are integrally formed with the middle shell 26; the pedal force bracket 13 comprises a pedal push rod 6 and two pedal force bracket arms 130 connected with the pedal push rod 6; the pedal force guide member 15 is provided at the end of the pedal force bracket arm 130; the electric power bracket 12 comprises an electric push rod 5 and two electric power bracket arms 120 connected with the electric push rod 5; the electrodynamic guide element 14 is arranged at the end of the electrodynamic carrier arm 120; the pedal push rod 6 and the electric push rod 5 are both of a cylindrical structure with openings at two ends, the pedal push rod 6 is embedded in the electric push rod 5, the pedal push rod and the electric push rod can slide relatively, and the pedal force bracket arm 130 is closer to the braking force output unit relative to the electric power bracket arm 120; the pedal force bracket arm 130 is connected with the guide rail 262 in a sliding way through the pedal force guide element 15, and the pedal force guide element 15 is matched with the outer wall of the guide rail 262 to realize external guide; the electrodynamic support arm 120 is connected with the guide rail 262 in a sliding way through the electrodynamic guide element 14, and the electrodynamic guide element 14 is matched with the inner wall of the guide rail 262 to realize inner guide; the pedal force transmission rod 7 is positioned in the pedal push rod 6; the pedal force support arm 130 is provided with a first guide hole 131, the electric power support arm 120 is provided with a second guide hole 121 at a corresponding position, and the anti-rotation triggering column 10 on the pedal force transfer plate 8 sequentially penetrates through the first guide hole 131 and the second guide hole 121.

As shown in fig. 10 and 11, the electric power bracket arm 120 is further provided with an elastic attachment 122 at the connection with the pedal force transmission plate 8; a first carrier 101 and a second carrier 102 are arranged on the side wall of the anti-rotation triggering column 10, and the axial length of the first carrier 101 is greater than that of the second carrier 102; the first carrier 101 is positioned in correspondence with the elastic appendage 122 for pressing the elastic appendage 122 in deformation when the brake pedal is blocked; the second carrier 102 is used to establish contact with the stop surfaces of the electrical power bracket 12 to prevent excessive deformation of the resilient appendage 122.

In other embodiments, the electromotive force bracket 12 and the pedal force bracket 13 may not share a common guide rail, but each has a respective guide rail, that is, the guide rail assembly includes an electromotive force guide rail and a pedal force guide rail, and the electromotive force guide rail and the pedal force guide rail may be an outer guide structure, an inner guide structure, or an inner and outer guide structure; the electric power rail and the pedal force rail can be both guide posts with concave, C-shaped or omega-shaped sections (as shown in figure 25); considering that the driver can only brake manually when the electric power generating unit malfunctions, in order to make the driver more labor-saving, the electric power bracket return spring may be installed only in the groove of the electric power rail. Of course, the pedal force support reset spring can be arranged in the concave groove of the pedal force guide rail, and compared with the existing scheme of middle reset of a single support, the aim of saving labor can be still achieved.

In other embodiments, the electric power guide rail and the pedal force guide rail can also be a solid guide post, a dovetail guide post, and the like.

In other embodiments, when the pedal force support 13 and the electric power support 12 share the same or the same set of guide rails, and the guide rails use guide pillars with concave, C-shaped or Ω -shaped cross sections, both the pedal force guide element 15 and the electric power guide element 14 can be internally guided by cooperating with the inner wall of the guide rails, and a support return spring is provided in the guide rails for simultaneously returning the pedal force support and the electric power support.

In other embodiments, if the return force of the piston return spring of the master cylinder 28 is large enough to satisfy the return of the pedal force bracket 13 and the electric power bracket 12, it is not necessary to install the return spring in the pedal force rail and the electric power rail.

As shown in fig. 1, the bearing assembly includes a bearing 24 and a bearing bush 21 provided on a bottom case 23 for supporting the gear box 4.

As shown in fig. 1 and 9, the electric power transmission unit comprises a transmission gear nut 4, an external thread 51 arranged on the outer wall of an electric push rod 5 of an electric power bracket 12, an assistance push piece 17 and an electric elastic element 18; the transmission gear nut 4 comprises a nut 41 with internal threads and a transmission gear 42 which is sleeved outside the nut 41 and fixedly connected with the nut; the external thread 51 may be directly machined on the electric push rod 5, or may be a threaded sleeve with an external thread, which is arranged outside the electric push rod 5 and is fixedly connected with the electric push rod as a whole.

The female 4 settings of driving gear are outside electric putter 5, and the transmission of two screw-thread fit: the female 4 of driving tooth is clockwise or anticlockwise the time of rotating, converts screw-thread fit's rotary motion into electric putter 5 along axial translation motion, and the female 4 of driving tooth is spacing because of being supported by bearing 24, can only rotate and can not follow axial translation.

The boosting push piece 17 is arranged between the pedal force bracket 13 and the braking force output unit; as shown in fig. 1 and 12, the boosting push member 17 is bowl-shaped as a whole, and one end thereof is connected to the pedal force bracket arm 130 of the pedal force bracket 13, and the other end thereof is in contact with the braking force output unit; the top of the power-assisted pushing piece 17 is provided with a through hole 171, the position of the through hole 171 is matched with the position of the pedal elastic element 35, and the size of the through hole 171 is larger than that of the first element 35, so that the pedal elastic element 35 can penetrate through the through hole 171 under the action of pedal force and transmit the pedal force to the braking force output unit; the electrodynamic elastic element 18 is arranged between the pedal force bracket 13 and the electrodynamic bracket 12; the electric elastic element 18 may be made of elastic rubber (may be an integral ring structure, or may be a split structure formed by a plurality of elastic bodies uniformly distributed along the circumference), or may be made of other elastic elements, such as a spring, a disc spring, etc. The electric power is transmitted to the braking force output unit through the transmission gear 42, the screw 41, the external thread 51, the electric power bracket 12, the electric elastic element 18, the pedal force bracket 13 and the power-assisted pushing piece 17 in sequence.

As shown in fig. 12, the boosting push-piece 17 is further provided with a plurality of guide structures 173 (four in this embodiment) having sector-shaped cross sections (in other embodiments, they may also be cylindrical), and the shape enclosed by the outer walls of the plurality of guide structures 173 having sector-shaped cross sections matches the shape of the outer side wall of the pedal force transmission plate 8, so that the pedal force transmission plate 8 can perform an axial rotation-proof motion along the plurality of guide structures 173 having sector-shaped cross sections of the boosting push-piece 17.

The sensor fixing frame 39 is arranged on the side of the power-assisted pushing piece 17, and four buckles 172 are symmetrically arranged on the top edge of the power-assisted pushing piece 17 so as to connect the power-assisted pushing piece 17 with the pedal force support 13.

As shown in fig. 1, 2, and 5, the returning unit in the present embodiment includes a pedal force return spring 11 and an electric power bracket return spring 33 for returning the electric power bracket 12; the electrodynamic force support restoring spring 33 is disposed in the C-shaped groove of the guide rail 262, one end of which is in contact with the upper cover 27 and the other end of which is in contact with the electrodynamic force guide member 14, thereby being used only for restoring the electrodynamic force support 12, at which time, when the electrodynamic force generating unit malfunctions, it is labor-saving for a driver to manually brake; the pedal force return spring 11 is disposed outside the rear section 72 of the pedal force transmission rod 7 and between the assist pusher 17 and the pedal force transmission plate 8.

As shown in fig. 9, 12, the electromotive force generating unit includes a sensor assembly, a control unit, a motor 31, and a transmission; the sensor component is used for monitoring the relative displacement generated between the pedal force transmission plate 8 and the pedal force bracket 13 and/or the electric power bracket 12 and transmitting the relative displacement to the control unit; the control unit controls the motor 31 to operate according to the displacement amount, and the electric power generated by the motor 31 is output to the gear box 4 through the transmission. The sensor component can be an optical coupling sensor, a resistance type displacement sensor or an electromagnetic Hall sensor; in the present embodiment, the sensor assembly is an electromagnetic hall sensor, and includes an induction magnet 36 and a hall sensor 38; the induction magnet 36 is arranged on the pedal force transmission plate 8, the Hall sensor 38 is arranged on the boosting push piece 17, and the positions of the induction magnet 36 and the Hall sensor correspond to each other; the transmission includes a motor output gear 2 and an intermediate gear set 3.

As shown in fig. 1, the braking force output unit includes a braking force output element a19 and a braking force output element B20 axially connected; the braking force output element a19 and the braking force output element B20 may be an integral piece or may be separate pieces.

The auxiliary braking principle and process of the embodiment are described below with reference to fig. 1, 17 and 18:

during braking, a driver applies pedal force to the pedal force input rod 1 to enable the pedal force input rod 1 to translate along a braking direction, so that the pedal force transmission rod 7, the pedal force transmission plate 8 and the pedal elastic element 35 are pushed to move together along the braking direction, and as the pedal force increases, the pedal elastic element 35 contacts the bottom of the braking force output element A19 and is compressed, and meanwhile, the pedal force is transmitted to the braking force output element A19 through the pedal elastic element 35;

accordingly, the pedal force transmission plate 8 translates to generate a relative displacement between the sensing magnet 36 and the hall sensor 38, the hall sensor 38 detects the relative displacement, and transmits a displacement signal to a control unit (usually ECU) in the electromotive force generation unit, the control unit receives the displacement signal to control the motor 31 to start and rotate forward/backward along with the forward/backward movement of the pedal force input rod 1, and the motor 31 operates to drive the motor output gear 2 to rotate, thereby driving the intermediate gear set 3 to rotate, further the intermediate gear set 3 drives the transmission gear nut 4 to rotate, so that the electric push rod 5 translates axially along the thread, the electric push rod 5 moves to drive the electromotive force support arm 120, the electric elastic element 18, the pedal force support 13, and the power push member 17 to translate together, and finally the resultant force of the pedal force and the electromotive force is transmitted to the braking force output element a19 through the power push member 17, the braking force output element A19 and the braking force output element B20 are pushed to move forwards, and then the piston in the master cylinder 28 is pushed to move forwards, so that the braking action is carried out;

when the relative displacement between the induction magnet 36 and the hall sensor 38 fixed on the boosting push piece 17 is kept unchanged, the ECU controls the motor 31 to stop running, and the torque in the original braking state is kept;

in the process of keeping braking, the motor 31 is in a torque keeping state, so that the motor output gear 2 is locked to achieve the braking state required by the pedal;

when braking is abandoned, the pedal force input rod 1 loses pedal force from the outside, the pedal force return spring 11 drives the pedal force transmission plate 8, the pedal force transmission rod 7 and the pedal force input rod 1 to return in sequence, and the master cylinder 28 also returns accordingly. The resetting of the pedal force transmission plate 8 causes the relative displacement between the induction magnet 36 and the hall sensor 38, the hall sensor 38 detects the relative displacement and transmits a displacement signal to a control unit (usually ECU) in the electromotive force generation unit, and the control unit controls the motor 31 to rotate reversely after receiving the displacement signal, so that the electric push rod 5, the electromotive force bracket 12 and the pedal force bracket 13 are reset.

The foot clamping prevention principle and process of the embodiment are described in the following with reference to fig. 15 and 16:

when braking is applied by means of the automatic emergency braking mode, the electric power carriage 12 is driven in translation by the electric push rod 5, which results in:

when the control unit receives a signal that braking is required, the control unit controls the motor 31 to start, when the brake pedal is not blocked (e.g. when not holding a foot), the force in the direction opposite to the braking direction is small because the only element exerting force in the direction opposite to the braking force is the pedal force return spring 11, and therefore the force in the direction opposite to the braking force is not sufficient to deform the resilient attachment 122 on the electric power bracket arm 120 or to change the spacing between the second carrier 102 on the pedal force transfer plate 8 and the upper surface of the electric power bracket 12 within a sufficient range. That is, the spacing between the pedal force transfer plate 8 and the electric power bracket 12 is also always above the threshold spacing that defines the occurrence of a brake pedal stuck event; when the distance between the pedal force transmission plate 8 and the electric power bracket 12 is less than or equal to the threshold distance, it is sensed by the control unit of the electric power generation unit that the brake pedal stuck event has occurred.

Under the normal braking condition, the pedal force transmission rod 7 is clamped with the pedal force transmission plate 8, no idle stroke exists between the pedal force transmission rod 7 and the pedal force transmission plate 8, and a driver has good brake pedal feeling when stepping on the brake pedal. In addition, since the pedal force transmission lever 7 and the pedal force transmission plate 8 are connected together, it is possible to quickly respond to the driver's interruption of the operation of the automatic emergency braking during the automatic emergency braking.

During automatic emergency braking, when a brake pedal is blocked by an obstacle, when an active radar of a vehicle detects that a front obstacle is within a braking threshold, a braking signal is sent to a control unit (the control unit is provided with an interface for receiving the braking signal) in an electric force generation unit, the control unit drives a motor 31 to operate to generate electric force after receiving the braking signal, at the moment, the movement of a pedal force input rod 1, a pedal force transmission rod 7, a pedal force transmission plate 8 and an anti-rotation triggering column 10 fixed on the pedal force transmission plate 8 is limited due to the obstacle, and at the moment, besides the force applied by a pedal force return spring 11, the obstacle applies a force opposite to the braking direction to the pedal force input rod 1, which results in that: the circumferential groove 74 on the pedal force transmission rod 7 is disengaged from the circumferential protrusion 81 of the pedal force transmission plate 8, so that the pedal force transmission rod 7 is separated from the pedal force transmission plate 8, the pedal force transmission rod 7 stops moving continuously along the braking force direction, the brake pedal is loosened, the aim of preventing the foot of a driver from being injured by clamping is achieved, the pedal force transmission plate 8 can still translate continuously under the action of the electric power, and the electric power transmission unit cannot be prevented from transmitting the electric power to the braking force output unit to implement braking action.

At the same time, the pedal force transmission plate 8 and the rotation-prevention triggering column 10 press the elastic attachment 122 on the electrodynamic support arm 120 to deform it by means of the first carrier 101, whereby the distance between the second carrier 102 and the upper surface of the electrodynamic support 12 is reduced to less than or equal to the threshold distance of the retardation event, the hall sensor 38 recognizes this relative displacement, and the control unit records the fault code of the retardation event, providing an information source for accident tracing.

Example 2:

as shown in fig. 19, the present embodiment differs from embodiment 1 only in that: the electric elastic element 18 is arranged in the boosting push piece 17 and is positioned between the pedal elastic element 35 and the braking force output element A19, and in a static state, no gap exists between the pedal elastic element 35 and the electric elastic element 18, and only an axial micro-force stroke exists.

Example 3:

as shown in fig. 20, the present embodiment differs from embodiment 1 only in that: be provided with spacing arch on the footboard power input rod 1, footboard power reset spring 11 sets up between the spacing arch of footboard power input rod 1 and footboard push rod 6, and the one end of footboard power reset spring 11 contacts with the spacing arch on the footboard power input rod 1, and the other end of footboard power reset spring 11 contacts with footboard push rod 6, and footboard power reset spring 11 mainly used promotes footboard power input rod 1 and the reset of footboard power transmission pole 7.

Example 4:

as shown in fig. 21, the present embodiment differs from embodiment 1 only in that: the pedal force transmission rod 7 is not in contact with the pedal force transmission plate 8.

Example 5:

as shown in fig. 22, the present embodiment is different from embodiment 3 only in that: the pedal force transmission rod 7 is composed of a front section 71 and a rear section 72 which are axially clamped, and the front section 71 and the rear section 72 can be separated at the clamped position under the condition of external force retardation only during automatic emergency braking. The clamping connection between the front section 71 and the rear section 72 has various implementation means, and in this embodiment, a spherical clamping head is matched and clamped with a claw-shaped clamping groove.

Example 6:

as shown in fig. 23, the present embodiment differs from embodiment 1 only in that: the pedal force transmission rod 7 is designed into a three-section structure and comprises a front section 71, a middle section 73 and a rear section 72 which are axially and sequentially clamped; the front section 71 and the middle section 73, and the middle section 73 and the rear section 72 are respectively clamped with the claw-shaped clamping grooves through spherical clamping heads. Only during automatic emergency braking, the front section 71 and the middle section 73 or the middle section 73 and the rear section 72 can be disengaged at the engagement point under the external force resistance.

Example 7:

as shown in fig. 24, the present embodiment differs from embodiment 1 only in that:

(1) the pedal force transmission rod 7 is composed of a front section 71 and a rear section 72 which are axially clamped, and the front section 71 and the rear section 72 can be separated at the clamped position under the condition of external force retardation only during automatic emergency braking. The clamping connection between the front section 71 and the rear section 72 has various implementation means, and in this embodiment, a spherical clamping head is matched and clamped with a claw-shaped clamping groove.

(2) The electric elastic element 18 is arranged between the boosting push piece 17 and the braking force output element A19, and the electric elastic element 18 is of an integral annular structure or a split structure consisting of a plurality of elastic bodies which are uniformly distributed along the circumference; under the action of the pedal force, the pedal elastic element 35 can pass through the electroelastic element 18 and transmit the braking force to the braking force output unit.

Claims

1. An asynchronous reset brake booster capable of automatically and emergently braking during blocking comprises

the pedal force transmission unit comprises a pedal force transmission rod (7) and a pedal force transmission plate (8); an anti-rotation triggering column (10) is arranged on the pedal force transmission plate (8);

the method is characterized in that:

the pedal force transmission rod (7) is axially clamped with the pedal force transmission plate (8), and the pedal force transmission rod (7) and the pedal force transmission plate (8) can be separated from the clamping part under the condition of external force blockage only during automatic emergency braking; or the pedal force transmission rod (7) and the pedal force transmission plate (8) are axially arranged in sequence and are only contacted and not connected;

the bracket assembly comprises a pedal force bracket (13) and an electric power bracket (12);

when the pedal force disappears, the electric power bracket (12) firstly starts to reset under the action of the second group of return springs, and then the pedal force bracket (13) is driven by the first group of return springs to carry out follow-up reset.

2. An asynchronous reset brake booster with automatic emergency braking during retardation according to claim 1 wherein: when the pedal force transmission rod (7) is axially clamped with the pedal force transmission plate (8), the clamping form of the two brackets is columnar clamping or spherical clamping.

3. An asynchronous reset brake booster with automatic emergency braking during retardation according to claim 2 wherein:

the bracket assembly further comprises a pedal force guide member (15) and an electric force guide member (14);

the pedal force bracket (13) comprises a pedal push rod (6) and at least one pedal force bracket arm (130) connected with the pedal push rod (6); the pedal force guide element (15) is arranged at the end of the pedal force bracket arm (130);

the electric power bracket (12) comprises an electric push rod (5) and at least one electric power bracket arm (120) connected with the electric push rod (5); the electrodynamic guide element (14) is arranged at the end of an electrodynamic support arm (120);

the pedal push rod (6) and the electric push rod (5) are both of a cylindrical structure with openings at two ends, the pedal push rod (6) is arranged in the electric push rod (5), and the pedal push rod and the electric push rod are in clearance fit and can move relatively along the axial direction;

the guide rail assembly comprises a guide rail (262), and the guide rail (262) is an inner and/or outer guide structure;

the pedal force bracket arm (130) is connected with the guide rail (262) in a sliding way through a pedal force guide element (15);

the electrodynamic support arm (120) is slidingly connected to the guide rail (262) through an electrodynamic guide element (14);

the pedal force transmission rod (7) is arranged in the pedal push rod (6);

the pedal force support arm (130) is provided with a first guide hole (131), the electric power support arm (120) is provided with a second guide hole (121), and the anti-rotation triggering column (10) on the pedal force transfer plate (8) sequentially penetrates through the first guide hole (131) and the second guide hole (121).

4. An asynchronous reset brake booster with automatic emergency braking during retardation according to claim 3 wherein:

the guide rail (262) is a guide pillar with a concave, C-shaped or omega-shaped section;

the first set of return springs is disposed on a central axis of the brake booster and the second set of return springs is disposed within the guide track (262).

5. An asynchronous reset brake booster with automatic emergency braking during retardation according to claim 4 wherein: the first group of return springs are return springs of a vehicle brake master cylinder.

6. An asynchronous reset brake booster with automatic emergency braking during retardation according to claim 3 wherein:

the pedal force guide element (15) is matched with the outer wall of the guide rail (262) to realize external guide;

the electrodynamic guiding element (14) is matched with the inner wall of the guide rail (262) to realize inner guiding;

the second group of return springs are electric power support return springs (33), one end of each electric power support return spring (33) is in contact with or connected with a shell of the brake booster, and the other end of each electric power support return spring is in contact with or connected with an electric power guide element (14).

7. An asynchronous reset brake booster with automatic emergency braking during retardation according to claim 2 wherein:

the electric power bracket (12) comprises an electric push rod (5) and at least one electric power bracket arm (120) connected with the electric push rod (5); the electrodynamic guide element (14) is arranged at the end of the electrodynamic support arm (120);

the guide rail assembly comprises a pedal force guide rail and an electric power guide rail, and the pedal force guide rail and the electric power guide rail are of inner and/or outer guide structures;

the pedal force bracket arm (130) is connected with the pedal force guide rail in a sliding way through a pedal force guide element (15);

the electric power support arm (120) is in sliding connection with the electric power guide rail through an electric power guide element (14);

the pedal force transmission rod (7) is arranged in the pedal push rod (6);

a first guide hole (131) is formed in the pedal force support arm (130), a second guide hole (121) is formed in the electric power support arm (120), and the anti-rotation triggering column (10) on the pedal force transfer plate (8) sequentially penetrates through the first guide hole (131) and the second guide hole (121).

8. An asynchronous reset brake booster with automatic emergency braking during retarding according to claim 7 wherein:

the electric power guide rail is a guide pillar with a concave, C-shaped or omega-shaped section;

the electrodynamic force guide element (14) is matched with the inner surface of the electrodynamic force guide rail to realize internal guide;

the second group of return springs are arranged in the electric power guide rail, one end of each second group of return springs is in contact with or connected with the shell of the brake booster, and the other end of each second group of return springs is in contact with or connected with the electric power guide element (14);

the first group of springs is a vehicle brake master cylinder return spring.

9. An asynchronous reset brake booster with automatic emergency braking during retarding according to claim 7 wherein:

the electric power guide rail and the pedal force guide rail are guide pillars with concave, C-shaped or omega-shaped sections;

the electric power guide element (14) and the pedal force guide element (15) are respectively matched with the inner surfaces of the electric power guide rail and the pedal force guide rail to realize internal guide;

the first group of return springs are arranged in the pedal force guide rail, one end of each first group of return springs is in contact with or connected with the shell of the brake booster, and the other end of each first group of return springs is in contact with or connected with the pedal force guide element (15).

10. An asynchronous reset brake booster with automatic emergency braking during retardation according to any of claims 1-9 wherein:

the end part of the pedal force transmission rod (7) close to the braking force output unit is provided with a pedal elastic element (35); an electric following stroke is formed between the pedal elastic element (35) and the braking force output unit; the electric following stroke is an idle stroke or a micro-force stroke.

11. An asynchronous reset brake booster with automatic emergency braking during retarding according to claim 10 wherein:

the pedal elastic element (35) comprises a first elastic body and a second elastic body which are sequentially arranged along the transmission direction of the braking force, one end of the second elastic body is connected with the first elastic body, and the other end of the second elastic body is contacted with the braking force output unit; the elastic coefficients of the first elastic body and the second elastic body are different.

12. An asynchronous reset brake booster with automatic emergency braking during retarding according to claim 10 wherein:

the electric power transmission unit comprises a transmission gear nut (4), an external thread (51) arranged on the outer wall of the electric push rod (5), an assistance push piece (17) and an electric elastic element (18);

the transmission gear nut (4) is composed of a screw nut (41) with internal threads and a transmission gear (42) with external transmission teeth, the transmission gear (42) is arranged outside the screw nut (41), the screw nut (41) is sleeved outside the electric push rod (5) and is connected with the external threads (51) through the internal threads to drive the electric push rod (5) to move along the axial direction;

the power-assisted pushing piece (17) is arranged between the pedal force bracket (13) and the braking force output unit; the boosting push piece (17) is integrally bowl-shaped, one end of the boosting push piece is connected with a pedal force support arm (130) of the pedal force support (13), and the other end of the boosting push piece is contacted with the braking force output unit; the bottom of the power-assisted pushing piece (17) is provided with a through hole (171) for the pedal elastic element (35) to pass through;

an electrodynamic elastic element (18) is arranged between the pedal force bracket (13) and the electrodynamic bracket (12);

the electric elastic element (18) is of an integrated annular structure or a split structure consisting of a plurality of elastic bodies which are uniformly distributed along the circumference;

the elastic coefficient of the electric elastic element (18) and the elastic coefficient of the pedal elastic element (35) can be the same or different.

13. An asynchronous reset brake booster with automatic emergency braking during retarding according to claim 10 wherein:

the electric power transmission unit comprises a transmission gear nut (4) with an internal thread (41) and an external transmission gear (42), an external thread (51) arranged on the outer wall of the electric push rod (5), an assistance push piece (17) and an electric elastic element (18);

the transmission gear nut (4) is sleeved outside the electric push rod (5) and is connected with the external thread (51) through the internal thread (41) in a threaded manner to drive the electric push rod (5) to move along the axial direction;

the electric elastic element (18) is arranged in the boosting push piece (17) and is positioned between the pedal elastic element (35) and the braking force output unit;

under the action of pedal force, the pedal elastic element (35) can pass through the electric elastic element (18) to transmit braking force to the braking force output unit;

14. An asynchronous reset brake booster with automatic emergency braking during retardation according to any of claims 1-9 wherein:

one or more bearing structures (261) are also arranged between the upper end surface and the lower end surface of the shell, the bearing structures (261) are used for fixing a brake master cylinder of the vehicle, and at least one bearing structure can bear acting force from the axial direction and/or the radial direction.

15. An asynchronous reset brake booster with automatic emergency braking during retardation according to claim 12 or 13 wherein: the reset unit further comprises a pedal force return spring (11);

the pedal force return spring (11) is arranged outside the pedal force transmission rod (7) and is positioned between the boosting push piece (17) and the pedal force transmission plate (8);

alternatively, the first and second electrodes may be,

the outer side wall of the pedal force input rod (1) is provided with a limiting bulge, and a pedal force return spring (11) is arranged between the limiting bulge and the pedal push rod (6).

16. An asynchronous reset brake booster capable of automatically and emergently braking during retardation comprises a shell, a pedal force input unit, an electric power generating unit, a supporting and guiding unit, a reset unit, a pedal force transmission unit, an electric power transmission unit and a braking force output unit;

the pedal force transmission unit comprises a pedal force transmission rod (7);

the method is characterized in that:

the pedal force transmission rod (7) comprises a front section (71) and a rear section (72) which are coaxially clamped; only when the brake is automatically applied in emergency, the front section (71) and the rear section (72) can be separated at the clamping part under the external force retardation; or the pedal force transmission rod (7) comprises a front section (71), a middle section (73) and a rear section (72) which are coaxially and sequentially clamped; only during automatic emergency braking, the front section (71) and the middle section (73) or the middle section (73) and the rear section (72) can be separated from the clamping part under the condition of external force retardation;