CN213892463U

CN213892463U - Line control brake system with backup function

Info

Publication number: CN213892463U
Application number: CN202022990359.1U
Authority: CN
Inventors: 初亮; 李世博; 许炎武; 赵迪; 常城; 陈超一; 聂荣真; 睢岩
Original assignee: Jilin University
Current assignee: Jilin University
Priority date: 2020-12-10
Filing date: 2020-12-10
Publication date: 2021-08-06
Anticipated expiration: 2030-12-10

Abstract

The utility model discloses a line control brake system with backup function, which comprises a brake control mechanism, an active brake pedal stroke simulator, a main energy supply device and a hydraulic pressure adjusting unit; brake master cylinder's I cavity liquid outlet A among the brake operating mechanism, II cavity liquid outlet B, III cavity inlet C respectively with active brake pedal stroke simulator's inlet D, inlet E, liquid outlet F tube coupling, the liquid outlet G of active brake pedal stroke simulator, liquid outlet H respectively with hydraulic pressure regulating unit's inlet M, inlet L tube coupling, main energy supply device's liquid outlet I, liquid outlet J respectively with hydraulic pressure regulating unit's inlet M, inlet L tube coupling, main energy supply device's inlet K and hydraulic pressure regulating unit's liquid outlet R all with the brake operating mechanism in the liquid outlet D tube coupling of liquid storage pot.

Description

Line control brake system with backup function

Technical Field

The utility model relates to a be applied to the drive-by-wire braking system in car braking system field, more exactly, the utility model relates to a drive-by-wire braking system with backup function.

Background

In recent years, with the progress of artificial intelligence technology, it has become possible to use a robot instead of a human to complete a driving task, an unmanned vehicle will inevitably become one of the development trends of future automobile technology, and an intelligent driving system will eventually replace a human to drive an automobile. The emergence of intelligent driving systems puts new and higher demands on braking systems, the newly introduced intelligent driving functions require that the braking systems can realize brake-by-wire through commands, the braking systems are ensured to have higher availability, and all key functions including brake-by-wire have redundant backup and are not limited to traditional conventional braking mechanical backup. To meet these needs, the brake-by-wire system should have a redundant backup function, and in addition, should have a higher pressure regulation capability, and at the same time, should add a pedal stroke simulation function, so that the brake pedal of the brake-by-wire system still has a pedal feel close to that of the conventional brake pedal.

Several patent applications are relevant to the present invention through retrieval:

the invention relates to a brake-by-wire system and a vehicle, which are named as 'brake-by-wire system' and 'vehicle' with the application number of 201710885196.0, wherein the publication number of Chinese patent is CN109552287A and publication number of 2019.04.02. The brake system executing mechanism designed by the invention comprises two electric brakes and two hydraulic brakes which are respectively controlled by a motor and a hydraulic unit and are respectively applied to a front shaft and a rear shaft. The invention has the disadvantage that the brake-by-wire system lacks a redundant backup function.

The invention relates to an electronic mechanical brake system with a backup brake system, which is named as 'an electronic mechanical brake system with a backup brake system' with the application number of 201811553147.8, and the Chinese patent publication number is CN109606340A and publication number 2019.04.12. The invention provides an electronic brake system which uses hydraulic pressure to simulate pedal feeling and uses electronic braking as a main braking mode and simultaneously reserves a hydraulic pipeline as a backup unit. The invention has the disadvantages that the backup brake system has insensitive response, difficult implementation and limited brake capacity, the electronic brake system actuating mechanism has complex structure and great control difficulty, and the four wheels adopt repeated actuating mechanisms, thereby greatly improving the cost of the brake system.

The Chinese patent publication No. CN110525409A, publication No. 2019.12.03, entitled redundant service brake System of vehicle, and application No. 201910753378.1. The design of the invention adopts the motor hydraulic pump as a power source of the backup braking system, and realizes the mode switching between the main braking system and the backup braking system through the electromagnetic valve. The invention has the defects that more electromagnetic valves need to be controlled, and the performance requirement of the backup braking system on the motor hydraulic pump is too high to exceed the self capacity.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that it has the performance requirement to drive-by-wire braking system to have overcome prior art and has surpassed the ability of current product, and the structure is complicated, and the control degree of difficulty is big, and redundant backup system's braking ability is limited, and the problem inconsistent with traditional vehicle is felt to the footboard, provides a drive-by-wire braking system with backup function.

In order to solve the technical problem, the utility model discloses an adopt following technical scheme to realize:

the brake-by-wire system with the backup function comprises a brake control mechanism, an active brake pedal stroke simulator, a main energy supply device and a hydraulic adjusting unit;

the brake control mechanism comprises a brake master cylinder and a liquid storage tank; the brake master cylinder is internally provided with three chambers which are arranged in series, namely a first chamber, a second chamber and a third chamber from left to right;

brake master cylinder's I cavity liquid outlet A and active brake pedal stroke simulator's inlet D brake pipe connection, brake master cylinder's II cavity liquid outlet B and active brake pedal stroke simulator's inlet E brake pipe connection, brake master cylinder's III cavity inlet C and active brake pedal stroke simulator's liquid outlet F brake pipe connection, active brake pedal stroke simulator's liquid outlet G and main energy supply device's liquid outlet I all with hydraulic pressure regulating unit's inlet M brake pipe connection, active brake pedal stroke simulator's liquid outlet H and main energy supply device's liquid outlet J all with hydraulic pressure regulating unit's inlet L brake pipe connection, main energy supply device's inlet K and hydraulic pressure regulating unit's liquid outlet R all with the liquid outlet D brake pipe connection of liquid storage pot.

The brake master cylinder in the technical scheme comprises a brake master cylinder body, a brake master cylinder first piston, a brake master cylinder second piston, a brake master cylinder first piston spring, a brake master cylinder second piston spring and a brake master cylinder push rod; the brake master cylinder body is a cylindrical structural member, the left end of the brake master cylinder body is closed, the right end of the brake master cylinder body is opened, a flange plate is arranged on the right end face of the brake master cylinder, and six liquid inlet and outlet ports which are threaded holes are arranged on the outer cylindrical surface of the brake master cylinder body; the brake master cylinder first piston spring, the brake master cylinder first piston, the brake master cylinder second piston spring, the brake master cylinder second piston and the brake master cylinder push rod are sequentially arranged in the brake master cylinder body, the brake master cylinder first piston, the brake master cylinder second piston and the brake master cylinder body are in sliding connection, and the rotation axes of the brake master cylinder first piston spring, the brake master cylinder first piston, the brake master cylinder second piston, the brake master cylinder push rod and the brake master cylinder body are collinear; the brake master cylinder is internally provided with three chambers which are isolated by a first piston of the brake master cylinder and a second piston of the brake master cylinder and can independently generate high-pressure brake fluid, the three chambers are arranged in series, a first chamber, a second chamber and a third chamber are sequentially arranged from left to right, and a mechanical inlet of the brake master cylinder is a push rod of the brake master cylinder; the brake master cylinder is fixed on the vehicle body through a flange.

In the technical scheme, the liquid storage tank is provided with four liquid outlets which are respectively a liquid outlet f, a liquid outlet r, a liquid outlet t and a liquid outlet d, the liquid outlet f, the liquid outlet r and the liquid outlet t are respectively connected with a liquid inlet a of a first cavity of the brake main cylinder, a liquid inlet b of a second cavity of the brake main cylinder and a liquid inlet c of a third cavity of the brake main cylinder through pipelines, and the liquid storage tank is arranged above the brake main cylinder.

The brake control mechanism in the technical scheme further comprises a brake pedal, a pedal displacement sensor and a brake master cylinder one-way valve; the brake pedal is installed below the front part of a driver in a carriage, the top end of a rotating part in the brake pedal is fixed on a pedal support through a pin shaft, the pedal support is fixed on a vehicle body through a bolt, the left side surface of the middle end of the rotating part in the brake pedal is in contact connection with the right end surface of a brake main cylinder push rod in a brake main cylinder, a pedal displacement sensor is fixed on the pedal support connected with the vehicle body, a movable arm of the pedal displacement sensor is connected with the rotating part in the brake pedal, a brake main cylinder check valve is installed between a liquid storage tank liquid outlet t and a brake main cylinder III cavity liquid inlet c, a port of the brake main cylinder check valve is connected with a liquid storage tank liquid outlet t hydraulic pipeline, and a port of the brake main cylinder check valve is connected with a brake main cylinder III cavity liquid inlet c hydraulic pipeline.

The active brake pedal stroke simulator comprises a motor controller, a motor, a driving gear, a toothed internal circulation nut, a ball, a screw mandrel ejector rod, a limit switch, a rear cover, a partition plate, a first thrust bearing, a second piston spring, a second piston sealing ring, a first piston spring, a third piston spring seat retainer ring, a third piston sealing ring, a simulator cylinder body, a simulator one-way valve, a simulator third liquid outlet electromagnetic valve, a simulator first liquid outlet electromagnetic valve, a simulator second liquid outlet electromagnetic valve and a brake main cylinder pressure sensor;

the simulator cylinder body is a cylindrical structural member, the left end and the right end of the simulator cylinder body are both opened, a flange plate for mounting is arranged on the outer cylindrical surface of a left end cylinder opening, three bolt holes are uniformly distributed on the flange plate, a three-section cylindrical stepped hole is machined along the central axis of the simulator cylinder body, the diameter of the three-section stepped hole is gradually reduced from left to right, and the three-section stepped hole is a first-section stepped hole, a second-section stepped hole and a third-section stepped hole in sequence, wherein a second piston and a second piston spring are installed in the first-section stepped hole, the first piston and the first piston spring are installed in the second-section stepped hole, the third-section stepped hole is an oil inlet and outlet hole of the simulator cylinder body and is machined into an internal threaded hole, the cylindrical wall of the first-section stepped hole is also machined with an air hole, the three-section cylindrical stepped holes are communicated with each other, and the rotation axes are collinear;

the third piston is a two-section stepped shaft, the right end shaft diameter is larger, an annular groove for placing a sealing ring is processed on the cylindrical surface of the right end shaft, the left end shaft diameter is smaller and used for mounting a third piston spring, a circular groove for placing a third piston spring seat check ring is processed on the cylindrical surface of the left end shaft, a circular hole is processed on the left end shaft along the rotation center line of the stepped shaft, and the diameter of the circular hole is slightly larger than that of a right end slide bar of the screw mandrel push rod; the first piston is a two-section stepped shaft, the right end shaft diameter is larger, the left end shaft diameter is smaller, the left end shaft diameter is used for mounting a third piston spring, an annular boss is arranged on the left end face of the shaft with the larger diameter and used for mounting the first piston spring, a circular stepped hole is machined along the rotation center line of the stepped shaft, the diameter of the right end of the stepped hole is larger and equal to the shaft diameter of the right end of the third piston, and the diameter of the left end of the stepped hole is smaller and equal to the shaft diameter of the left end of the third piston; the second piston is a two-section stepped shaft, the right end shaft diameter is larger, a circular boss is arranged on the right end surface and used for mounting a first piston spring, an annular groove used for placing a sealing ring is processed on the cylindrical surface of the right end shaft, the left end shaft diameter is smaller and used for mounting a second piston spring, a circular through hole is processed along the rotation center line of the stepped shaft, and the diameter of the through hole is slightly larger than the left end shaft diameter of the first piston;

the simulator comprises a simulator cylinder body, a back cover, a toothed internal circulation nut, a screw mandrel ejector rod, a screw roller path, a screw mandrel ejector rod, a third piston, a second piston, a first piston and a second piston, wherein the simulator cylinder body is arranged on the right end surface of a partition plate through a bolt, the back cover is arranged on the left end surface of the partition plate through a rivet, the toothed internal circulation nut is arranged between the back cover and the partition plate through a first thrust bearing and a second thrust bearing, the left end surface and the right end surface of the first thrust bearing are respectively in contact connection with the back cover and the toothed internal circulation nut, the left end surface and the right end surface of the second thrust bearing are respectively in contact connection with the toothed internal circulation nut and the partition plate, the screw mandrel ejector rod is arranged in a spiral roller path of a central hole of the toothed internal circulation nut through balls and is in rolling connection, the right end surface of the screw mandrel ejector rod is inserted into a stepped hole of the simulator cylinder body, the right end of the screw mandrel ejector rod is sheathed with the third piston, the left end of the third piston is sheathed in a second piston, the first section of the first piston is sheathed in a sliding connection with the first section of the first piston, the first piston spring is sleeved on a circular boss on the second end face of the left side of the first piston, the second piston spring and the third piston spring are respectively arranged on a left end shaft of the second piston and a left end shaft of the third piston, a third piston spring seat is sleeved on the left end of the third piston in a transition fit manner, a third piston spring seat check ring is arranged in a circular groove at the left end of the third piston, the left end face of the third piston spring seat is in contact connection with the right end face of the third piston spring seat check ring, a second piston sealing ring and a third piston sealing ring are respectively sleeved in annular grooves of the second piston and the third piston, the motor is arranged on the right end face of a partition plate below a simulator cylinder body, a driving gear is sleeved on an output shaft of the motor in an interference fit manner and is connected with a toothed internal circulation nut in a meshing manner, a motor controller is arranged on the right end face of the motor shell, and the motor is connected with a motor controller through an electric wire, the limit switch is arranged at the central position of the rear cover and is connected with the motor controller by a limit switch signal wire, the port a of the simulator electromagnetic valve, the port p of the third liquid outlet electromagnetic valve of the simulator and the port a of the one-way valve of the simulator are all connected with oil inlet and outlet hole hydraulic pipelines on the simulator cylinder body, the port p of the simulator electromagnetic valve and the port p of the first liquid outlet electromagnetic valve of the simulator are all connected with a D port hydraulic pipeline of the active brake pedal stroke simulator, the port a of the first liquid outlet electromagnetic valve of the simulator is connected with a G port hydraulic pipeline of the active brake pedal stroke simulator, the port p of the second liquid outlet electromagnetic valve of the simulator and a brake master cylinder pressure sensor are all connected with an E port hydraulic pipeline of the active brake pedal stroke simulator, the port a of the second liquid outlet electromagnetic valve of the simulator is connected with an H port hydraulic pipeline of the active brake pedal stroke simulator, and the port a of the third liquid outlet electromagnetic valve of the simulator are connected with a port, And ports p of the simulator one-way valves are connected with a port F of the active brake pedal stroke simulator through hydraulic pipelines.

The main energy supply device in the technical scheme comprises an electric hydraulic cylinder, an electric hydraulic cylinder pressure sensor, an electric hydraulic cylinder first liquid outlet electromagnetic valve and an electric hydraulic cylinder second liquid outlet electromagnetic valve;

the electric hydraulic cylinder comprises an electric hydraulic cylinder body, an electric hydraulic cylinder piston spring, an electric hydraulic cylinder piston, an electric hydraulic cylinder ball screw and an electric hydraulic cylinder motor; the cylinder body of the electric hydraulic cylinder is a cylindrical structural member, the left end and the right end of the cylinder body are both provided with holes, the diameter of the left end opening is smaller and is processed into a threaded hole, the hole is an oil inlet and outlet hole a of the electric hydraulic cylinder, the diameter of the right end opening is larger, and an oil inlet and outlet hole p is arranged on the outer cylindrical surface of the cylinder body of the electric hydraulic cylinder; a center hole is formed in the center of the right end of the electric hydraulic cylinder piston, a spiral raceway for mounting balls is arranged on the inner cylindrical surface of the center hole, and a ball screw of the electric hydraulic cylinder is provided with a spiral raceway matched with the spiral raceway of the electric hydraulic cylinder piston; the electric hydraulic cylinder piston spring and the electric hydraulic cylinder piston are sequentially arranged in the electric hydraulic cylinder body, the electric hydraulic cylinder piston is in sliding connection with the electric hydraulic cylinder body, the left end of the electric hydraulic cylinder ball screw is arranged in a central hole at the right end of the electric hydraulic cylinder piston and is in rolling connection, the right end of the electric hydraulic cylinder ball screw is connected with the electric hydraulic cylinder motor through a transmission mechanism, and the electric hydraulic cylinder ball screw can convert the rotary motion of the electric hydraulic cylinder motor into the linear motion of the electric hydraulic cylinder piston;

the first liquid solenoid valve of hydraulic cylinder's p mouth, the electric cylinder second goes out the p mouth of liquid solenoid valve, electric cylinder pressure sensor all with electric cylinder business turn over oilhole a hydraulic line connection, the first liquid solenoid valve's of electric cylinder a mouth and the I mouth hydraulic line connection of main energy supply device, the electric cylinder second goes out the liquid solenoid valve's an mouth and the J mouth hydraulic line connection of main energy supply device, electric cylinder business turn over oilhole p and the K mouth hydraulic line connection of main energy supply device.

The hydraulic adjusting unit in the technical scheme comprises a right rear wheel check valve, a right rear wheel liquid inlet electromagnetic valve, a left front wheel check valve, a left front wheel liquid inlet electromagnetic valve, a right front wheel check valve, a right front wheel liquid inlet electromagnetic valve, a left rear wheel check valve, a left rear wheel liquid inlet electromagnetic valve, a right rear wheel liquid outlet electromagnetic valve, a left front wheel liquid outlet electromagnetic valve, a right front wheel liquid outlet electromagnetic valve and a left rear wheel liquid outlet electromagnetic valve;

an opening a of the right rear wheel check valve, an opening P of the right rear wheel liquid inlet electromagnetic valve, an opening a of the left front wheel check valve and an opening P of the left front wheel liquid inlet electromagnetic valve are all connected with an M opening hydraulic pipeline of the hydraulic adjusting unit, an opening a of the right front wheel check valve, an opening P of the right front wheel liquid inlet electromagnetic valve, an opening a of the left rear wheel check valve and an opening P of the left rear wheel liquid inlet electromagnetic valve are all connected with an L opening hydraulic pipeline of the hydraulic adjusting unit, an opening P of the right rear wheel check valve, an opening a of the right rear wheel liquid inlet electromagnetic valve and an opening P of the right rear wheel liquid outlet electromagnetic valve are all connected with a Q opening hydraulic pipeline of the hydraulic adjusting unit, an opening P of the left front wheel check valve, an opening a of the left front wheel liquid inlet electromagnetic valve and an opening P of the left front wheel liquid outlet electromagnetic valve are all connected with a P opening hydraulic pipeline of the hydraulic adjusting unit, an opening P of the right front wheel check valve, an opening a opening of the right front wheel liquid inlet electromagnetic valve and a P opening of the right front wheel liquid outlet electromagnetic valve are all connected with an O opening hydraulic pipeline of the hydraulic adjusting unit, the port a of the right rear wheel liquid outlet electromagnetic valve, the port a of the left front wheel liquid outlet electromagnetic valve, the port a of the right front wheel liquid outlet electromagnetic valve and the port a of the left rear wheel liquid outlet electromagnetic valve are all connected with the port R hydraulic pipeline of the hydraulic adjusting unit.

Compared with the prior art, the beneficial effects of the utility model are that:

1. a drive-by-wire braking system hardware simple structure with backup function, only need install active brake pedal stroke simulator additional on the basis of on-line control moving system, and only need control a small amount of solenoid valves and active brake pedal stroke simulator among conventional braking process and the redundant backup braking process, the control difficulty is low.

2. An active brake pedal stroke simulator among drive-by-wire braking system with backup function integrated footboard sensation analog function and integrated initiative pressure boost, pressurize, initiative decompression pressure regulating function as an organic whole, compensatied the not enough of traditional hydraulic pressure regulating unit pressure regulating capacity.

3. A drive-by-wire braking system with backup function both can feel through active brake pedal stroke simulator simulation footboard at main energy supply device during operation, can be after main energy supply device became invalid again, through the active pressure regulatory function of active brake pedal stroke simulator, dynamic adjustment brake master cylinder pressure and footboard feel, when guaranteeing that brake pedal feel is unanimous with traditional car, realize braking system's redundant backup design, furthest has ensured driving safety.

4. A drive-by-wire braking system with backup function can install in hybrid vehicle and electric automobile, through accurate brake pressure regulation, can let hydraulic braking and the better cooperation of motor braking, furthest's performance motor regenerative braking's ability promotes hybrid vehicle and electric automobile's menstruation nature by a wide margin.

Drawings

The invention will be further described with reference to the accompanying drawings:

fig. 1 is a schematic diagram of a brake-by-wire system with a backup function according to the present invention;

fig. 2 is a schematic diagram illustrating a structural composition of an active brake pedal travel simulator in a brake-by-wire system with a backup function according to the present invention;

fig. 3 is a right side view of the simulator main body of the active brake pedal stroke simulator in the brake-by-wire system with backup function according to the present invention;

fig. 4 is a schematic diagram of a main energy supply device in a brake-by-wire system with a backup function according to the present invention;

fig. 5 is a schematic diagram illustrating a structural composition of a hydraulic pressure adjusting unit in a brake-by-wire system with a backup function according to the present invention;

in the figure: 1. a brake control mechanism, 2, a liquid storage tank, 3, a brake master cylinder check valve, 4, a brake master cylinder push rod, 5, a pedal displacement sensor, 6, a brake pedal, 7, a brake master cylinder body, 8, a brake master cylinder second piston, 9, a brake master cylinder second piston spring, 10, a brake master cylinder first piston, 11, a brake master cylinder first piston spring, 12, an active brake pedal stroke simulator, 13, a main energy supply device, 14, a hydraulic pressure adjusting unit, 15, a right rear wheel, 16, a left front wheel, 17, a right front wheel, 18, a left rear wheel, 19, a toothed internal circulation nut, 20, a second thrust bearing, 21, a first thrust bearing, 22, a limit switch, 23, a screw rod ejector rod, 24, a ball, 25, a driving gear, 26, a limit switch signal line, 27, a first motor fixing bolt, 28, a motor, 29, a motor controller, 30, a second piston sealing ring, 31. a simulator cylinder, 32, a third piston seal ring, 33, an oil inlet and outlet hole, 34, a first piston, 35, a third piston, 36, a first piston spring, 37, a third piston spring, 38, a third piston spring seat, 39, a third piston spring seat retainer ring, 40, a second piston, 41, a second piston spring, 42, a vent hole, 43, a second partition connecting bolt, 44, a partition, 45, a fourth rear cover connecting rivet, 46, a rear cover, 47, a simulator check valve, 48, a simulator third liquid outlet electromagnetic valve, 49, a simulator electromagnetic valve, 50, a simulator first liquid outlet electromagnetic valve, 51, a simulator second liquid outlet electromagnetic valve, 52, a brake master cylinder pressure sensor, 53, a second motor fixing bolt, 54, a seventh rear cover connecting rivet, 55, a third partition connecting bolt, 56, a sixth rear cover connecting rivet, 57, a fifth rear cover connecting rivet, 58. the hydraulic control system comprises a third rear cover connecting rivet, 59, a second rear cover connecting rivet, 60, a first partition connecting bolt, 61, a first rear cover connecting rivet, 62, an electric hydraulic cylinder pressure sensor, 63, an electric hydraulic cylinder first liquid outlet electromagnetic valve, 64, an electric hydraulic cylinder second liquid outlet electromagnetic valve, 65, an electric hydraulic cylinder body, 66, an electric hydraulic cylinder piston spring, 67, an electric hydraulic cylinder piston, 68, an electric hydraulic cylinder ball screw, 69, an electric hydraulic cylinder motor, 70, a right rear wheel check valve, 71, a right rear wheel liquid inlet electromagnetic valve, 72, a left front wheel check valve, 73, a left front wheel liquid inlet electromagnetic valve, 74, a right front wheel check valve, 75, a right front wheel liquid inlet electromagnetic valve, 76, a left rear wheel check valve, 77, a left rear wheel liquid inlet electromagnetic valve, 78, a right rear wheel liquid outlet electromagnetic valve, 79, 80, a right front wheel liquid outlet electromagnetic valve, 81, and a left rear wheel liquid outlet electromagnetic valve.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings:

a drive-by-wire braking system with backup function include braking operating mechanism 1, active brake pedal stroke simulator 12, main energy supply device 13 and hydraulic pressure regulating unit 14.

Referring to fig. 1, the brake operating mechanism 1 includes a master cylinder, a reservoir 2, a brake pedal 6, a pedal displacement sensor 5, and a master cylinder check valve 3.

The brake master cylinder comprises a brake master cylinder body 7, a brake master cylinder first piston 10, a brake master cylinder second piston 8, a brake master cylinder first piston spring 11, a brake master cylinder second piston spring 9 and a brake master cylinder push rod 4; the brake main cylinder body 7 is a cylindrical structural member, the left end of the brake main cylinder body is closed, the right end of the brake main cylinder body is opened, a flange plate is arranged on the right end face of the brake main cylinder, and six liquid inlet and outlet ports which are threaded holes are arranged on the outer cylindrical surface of the brake main cylinder body 7; the brake master cylinder first piston spring 11, the brake master cylinder first piston 10, the brake master cylinder second piston spring 9, the brake master cylinder second piston 8 and the brake master cylinder push rod 4 are sequentially arranged in the brake master cylinder body 7, the brake master cylinder first piston 10, the brake master cylinder second piston 8 and the brake master cylinder body 7 are in sliding connection, and the rotation axes of the brake master cylinder first piston spring 11, the brake master cylinder first piston 10, the brake master cylinder second piston spring 9, the brake master cylinder second piston 8, the brake master cylinder push rod 4 and the brake master cylinder body 7 are collinear; the brake master cylinder is internally provided with three chambers which are isolated by a first piston 10 of the brake master cylinder and a second piston 8 of the brake master cylinder and can independently generate high-pressure brake fluid, the three chambers are arranged in series, a first chamber, a second chamber and a third chamber are sequentially arranged from left to right, and a mechanical inlet of the brake master cylinder is a push rod 4 of the brake master cylinder, so that mechanical energy input by a pedal of a driver can be converted into hydraulic energy.

The liquid storage tank 2 is generally made of hard plastic materials, and has four liquid outlets, namely a liquid outlet f, a liquid outlet r, a liquid outlet t and a liquid outlet d, and the liquid storage tank 2 is used for storing brake fluid and detecting the residual amount of the brake fluid.

The brake pedal 6 comprises a rotating part and a pedal support, the rotating part is installed on the pedal support through a pin shaft through hole in the top end of the rotating part and a pin shaft, the rotating part is rotatably connected with the pedal support, the pedal support is fixed with a vehicle body through a bolt, and the brake pedal 6 amplifies the pedal force operated by a driver through the lever principle and can reflect the braking intention of the driver.

The pedal displacement sensor 5 adopts a pull-wire type displacement sensor of CLM series of ASM company of Germany, and a movable arm on the pedal displacement sensor 5 can measure the angular displacement of the brake pedal 6 and feed the angular displacement back to the brake controller, so that the pedal displacement sensor is used for acquiring the pedal displacement information of a driver when the braking energy of the automobile is recovered.

The brake master cylinder check valve 3 adopts a straight-through type check valve, the forward opening pressure is 0.04MPa, and the brake master cylinder check valve 3 is used for controlling the flow direction of brake fluid, so that the brake fluid can only flow from the port p to the port a of the brake master cylinder check valve 3, but the brake fluid cannot flow back.

The position and the connection mode of the specific components are as follows: the brake pedal 6 is installed below the front part of a driver in a carriage, the top end of a rotating part in the brake pedal 6 is fixed on a pedal support through a pin shaft, the pedal support is fixed on the vehicle body through a bolt, and the left side surface of the middle end of the rotating part in the brake pedal 6 is in contact connection with the right end surface of a brake master cylinder push rod 4 in a brake master cylinder. The pedal displacement sensor 5 is fixed on a pedal bracket connected with the vehicle body, the pedal displacement sensor 5 is fixed on the pedal bracket connected with the vehicle body, and a movable arm of the pedal displacement sensor 5 is connected with a rotating part in the brake pedal 6. The brake master cylinder is fixed on the vehicle body through a flange plate, a liquid outlet A of a first cavity of the brake master cylinder is connected with a brake pipeline of a liquid inlet D of the active brake pedal stroke simulator 12, a liquid outlet B of a second cavity of the brake master cylinder is connected with a brake pipeline of a liquid inlet E of the active brake pedal stroke simulator 12, and a liquid inlet C of a third cavity of the brake master cylinder is connected with a brake pipeline of a liquid outlet F of the active brake pedal stroke simulator 12. The liquid outlet f, the liquid outlet r and the liquid outlet t of the liquid storage tank 2 are respectively connected with a liquid inlet a of a first cavity of the brake master cylinder, a liquid inlet b of a second cavity of the brake master cylinder and a liquid inlet c of a third cavity of the brake master cylinder through pipelines, and the liquid storage tank 2 is arranged above the brake master cylinder. The brake master cylinder check valve 3 is arranged between a liquid outlet t of the liquid storage tank 2 and a liquid inlet c of a III cavity of the brake master cylinder, a p port of the brake master cylinder check valve 3 is connected with a hydraulic pipeline of the liquid outlet t of the liquid storage tank 2, and an a port of the brake master cylinder check valve 3 is connected with a hydraulic pipeline of the liquid inlet c of the III cavity of the brake master cylinder.

Referring to fig. 2 and 3, the active brake pedal stroke simulator 12 includes a toothed internal circulation nut 19, a second thrust bearing 20, a first thrust bearing 21, a limit switch 22, a screw rod carrier 23, a ball 24, a driving gear 25, a limit switch signal line 26, a first motor fixing bolt 27, a motor 28, a motor controller 29, a partition 44, a fourth rear cover connecting rivet 45, a rear cover 46, a second motor fixing bolt 53, a seventh rear cover connecting rivet 54, a sixth rear cover connecting rivet 56, a fifth rear cover connecting rivet 57, a third rear cover connecting rivet 58, a second rear cover connecting rivet 59, a first rear cover connecting rivet 61, a second piston seal 30, a simulator cylinder 31, a third piston seal 32, an oil inlet/outlet hole 33, a first piston 34, a third piston 35, a first piston spring 36, a third piston spring 37, a third piston spring 38, a third piston spring seat, a fourth piston spring seat, a fifth piston spring seat, a fourth piston spring seat, a fifth piston spring seat, a fourth piston spring seat, a fifth piston spring seat, a fourth piston spring seat, a fifth piston spring seat, a, The hydraulic brake system comprises a third piston spring seat retainer ring 39, a second piston 40, a second piston spring 41, a vent hole 42, a second partition plate connecting bolt 43, a third partition plate connecting bolt 55, a first partition plate connecting bolt 60, a simulator one-way valve 47, a simulator third liquid outlet electromagnetic valve 48, a simulator electromagnetic valve 49, a simulator first liquid outlet electromagnetic valve 50, a simulator second liquid outlet electromagnetic valve 51 and a brake master cylinder pressure sensor 52.

The specific specifications and functions are as follows: the active brake pedal stroke simulator 12 mainly plays a role in simulating pedal feel and serving as a backup energy supply device to realize active pressurization, pressure maintaining and active pressure reduction when the main energy supply device 13 fails.

The toothed internal circulation nut 19 is a disc-type structural member, a cylindrical boss is arranged at the right end of the toothed internal circulation nut 19, the circle center of the boss is overlapped with the center of the toothed internal circulation nut 19, teeth meshed with the driving gear 25 are arranged on the outer cylindrical surface of the periphery of the toothed internal circulation nut 19, a central through hole is formed in the center of the toothed internal circulation nut 19, and a spiral raceway for mounting the ball 24 is arranged on the inner cylindrical surface of the central through hole.

The screw mandrel 23 consists of a left section and a right section, the left section is a screw mandrel which is provided with a spiral raceway and matched with a central through hole of the toothed internal circulation nut 19 and a ball 24, the right section is a cylindrical sliding rod with a smooth surface, and the screw mandrel 23 plays a role in converting the rotary motion of the toothed internal circulation nut 19 into linear motion.

The first thrust bearing 21 and the second thrust bearing 20 can adopt a thrust ball bearing or a thrust cylindrical roller bearing, and the first thrust bearing 21 and the second thrust bearing 20 can bear the radial acting force of the toothed internal circulation nut 19 and can limit the axial displacement of the toothed internal circulation nut 19.

The simulator cylinder body 31 is a cylindrical structural member, the left end and the right end of the simulator cylinder body are both open, a flange plate for installation is arranged on the outer cylindrical surface of the left end cylinder opening, three bolt holes are uniformly distributed in the flange plate, a three-section cylindrical stepped hole is machined along the central axis of the simulator cylinder body 31, the diameter of the three-section stepped hole gradually decreases from left to right, and sequentially comprises a first section of stepped hole, a second section of stepped hole and a third section of stepped hole, wherein a second piston 40 and a second piston spring 41 are installed in the first section of stepped hole, a first piston 34 and a first piston spring 36 are installed in the second section of stepped hole, the third section of stepped hole is an oil inlet and outlet hole 33 of the simulator cylinder body 31 and is machined into an internal threaded hole, a vent hole 42 is further machined in the cylindrical wall of the first section of stepped hole, and the three-section cylindrical stepped holes are mutually communicated and have collinear rotation axes.

The partition plate 44 is a disc-type structural member, an outer contour line of an outer circular surface of the partition plate 44 is composed of two eccentric circles and two outer tangent lines of the two eccentric circles, the diameter of an upper eccentric circle on the partition plate 44 is large, the diameter of a lower eccentric circle on the partition plate 44 is small, two central through holes are processed in the center of the two eccentric circles of the partition plate 44, three uniformly-distributed bolt holes, two uniformly-distributed bolt holes and seven rivet holes are further processed on the plane of the partition plate 44, the three uniformly-distributed threaded hole distribution circles are concentrically arranged with the upper eccentric circle on the partition plate 44, the two uniformly-distributed threaded hole distribution circles are concentrically arranged with the lower eccentric circle on the partition plate 44, the seven rivet hole distribution circles are concentrically arranged with the upper eccentric circle on the partition plate 44, the diameter of the three uniformly-distributed threaded hole distribution circles is small, the diameter of the seven rivet holes distribution circles is large, and a circular boss for mounting the second thrust bearing 20 is arranged on the left end surface of the partition plate 44.

The rear cover 46 is a stepped cylindrical structural member, the left end of the structural member is closed, the right end of the structural member is open, a central through hole for mounting the limit switch 22 is processed at the left end, the outer contour of the outer circular surface of the cylinder opening at the right end is the same as that of the outer circular surface of the partition plate 44, a flange plate for mounting is arranged on the outer circular surface of the cylinder opening at the right end, and seven rivet holes are arranged on the flange plate and matched with the seven rivet holes on the partition plate 44 for use; two stepped holes are formed in the rear cover 46, the left-end stepped hole is a central circular hole and has a smaller diameter, the inner contour of the right-end stepped hole has the same shape as the outer contour of the outer circumferential surface of the partition 44, the two stepped holes are communicated with each other, the rotating shaft of the left-end stepped hole and the upper eccentric circular rotating shaft of the right-end stepped hole are collinear, and a circular boss for mounting the first thrust bearing 21 is arranged on the left end surface of the right-end stepped hole.

The third piston 35 is a two-section stepped shaft, the right end shaft diameter is large, an annular groove for placing a third piston sealing ring 32 is processed on the cylindrical surface of the right end shaft, the left end shaft diameter is small for installing a third piston spring 37, a circular groove for placing a third piston spring seat retaining ring 39 is processed on the cylindrical surface of the left end shaft, a circular hole is processed on the left end shaft along the rotation center line of the stepped shaft, and the diameter of the circular hole is slightly larger than that of the slide bar of the screw mandrel ejector rod 23.

First piston 34 be two segmentation step shafts, the right-hand member shaft diameter is great, the left end shaft diameter is less, the left end shaft diameter is used for installing third piston spring 37, be provided with ring shape boss on the left end face of the diameter great axle for install first piston spring 36, along the processing of step shaft centre of rotation line there is circular shoulder hole, the shoulder hole right-hand member diameter is great, equals with third piston 35 right-hand member shaft diameter, the shoulder hole left end diameter is less, equals with third piston 35 left end shaft diameter.

The second piston 40 is a two-section stepped shaft, the right end shaft diameter is larger, a circular ring-shaped boss is arranged on the right end face and used for mounting the first piston spring 36, an annular groove used for placing the second piston sealing ring 30 is processed on the cylindrical surface of the right end shaft, the left end shaft diameter is smaller and used for mounting the second piston spring 41, a circular through hole is processed along the rotation center line of the stepped shaft, and the diameter of the through hole is slightly larger than that of the left end shaft diameter of the first piston 34.

The first piston spring 36 adopts a cylindrical spiral spring, has low rigidity, and mainly simulates the pressure volume characteristic of a wheel cylinder during low-intensity braking in a pedal stroke simulation state; the second piston spring 41 is a cylindrical coil spring with high rigidity, and mainly simulates the pressure volume characteristic of a wheel cylinder during high-intensity braking in a pedal stroke simulation state, and the third piston spring 37 is a cylindrical coil spring with high rigidity, and mainly enables the third piston 35 to move towards the direction of the screw mandrel 23 (namely leftwards relative to the second piston 40) in a pressure reduction state so as to realize the function of active pressure reduction.

The third piston spring seat 38 is a circular ring-shaped structural member and is used for mounting and fixing the third piston spring 37.

Third piston spring seat retaining ring 39 be the ring form structure, adopt aluminum alloy material, for convenient installation, processing is jagged on the ring. The third piston spring seat retainer ring 39 functions to limit the axial displacement of the third piston spring seat 38.

The second piston seal ring 30 and the third piston seal ring 32 are both O-shaped seal rings, and are used for sealing brake fluid.

The first rear cover connecting rivet 61, the second rear cover connecting rivet 59, the third rear cover connecting rivet 58, the fourth rear cover connecting rivet 45, the fifth rear cover connecting rivet 57, the sixth rear cover connecting rivet 56 and the seventh rear cover connecting rivet 54 are half-head rivets for connecting the rear cover 46 and the partition 44.

The first partition plate connecting bolt 60, the second partition plate connecting bolt 43 and the third partition plate connecting bolt 55 adopt common fine-thread hexagon bolts and are used for connecting the simulator cylinder body 31 and the partition plate 44; the first motor fixing bolt 27 and the second motor fixing bolt 53 are ordinary fine hexagonal bolts for connecting the motor 28 and the partition plate 44.

The motor 28 is a brush direct current permanent magnet motor, and the motor 28 is a power source of the active brake pedal stroke simulator 12.

The brake master cylinder pressure sensor 52 adopts an active pressure sensor with the model number 303 produced by BOSCH company, and the pressure of the brake master cylinder can be measured by inputting 5V power supply voltage.

The first simulator liquid outlet electromagnetic valve 50 and the second simulator liquid outlet electromagnetic valve 51 are two-position two-way normally open electromagnetic valves, can realize bidirectional flow of brake fluid, and are used for controlling the on-off of the brake master cylinder and the hydraulic pressure adjusting unit 14.

The simulator solenoid valve 49 and the simulator third liquid outlet solenoid valve 48 are two-position two-way normally closed solenoid valves, and can realize bidirectional flow of brake fluid when electrified, so as to control the on-off of the brake master cylinder and the active brake pedal stroke simulator 12.

The simulator check valve 47 adopts a straight-through type check valve, the forward opening pressure is 0.04MPa, and the simulator check valve 47 is used for controlling the flow direction of brake fluid, so that the brake fluid can only flow from the port p to the port a of the simulator check valve 47, but the brake fluid cannot flow back.

The position and the connection mode of the concrete components are as follows:

the first piston 34 and the second piston 40 are sequentially arranged in the first section stepped hole and the second section stepped hole of the simulator cylinder 31 and are in sliding connection, the second piston sealing ring 30 is sleeved in the annular groove of the second piston 40, the third piston 35 is sleeved in the first piston 34 and is in sliding connection, and the third piston sealing ring 32 is sleeved in the annular groove of the third piston 35. The first piston spring 36 is sleeved on the circular boss on the second end face on the left side of the first piston 34, the left end face of the first piston spring 36 is in contact connection with the bottom face of the circular boss on the right end face of the second piston 40, and the right end face of the first piston spring 36 is in contact connection with the bottom face of the circular boss on the left end face of the first piston 34; a second piston spring 41 and a third piston spring 37 are respectively arranged on left end shafts of a second piston 40 and a third piston 35, the left end surface of the second piston spring 41 is in contact connection with the right end surface of a partition plate 44, the right end surface of the second piston spring 41 is in contact connection with the left end surface of a large-diameter shaft of the second piston 40, a third piston spring seat 38 is sleeved at the left end of the third piston 35 in a transition fit manner, the left end surface of the third piston spring 37 is in contact connection with the right end surface of the third piston spring seat 38, and the right end surface of the third piston spring 37 is in contact connection with the left end surface of a small-diameter shaft of the first piston 34; the pretension of the second piston spring 41 is greater than the pretension of the first piston spring 36. The third piston spring seat retainer 39 is mounted in a circular groove at the left end of the third piston 35, and the left end surface of the third piston spring seat 38 is in contact connection with the right end surface of the third piston spring seat retainer 39. The motor 28 is mounted on the right end surface of the partition plate 44 below the simulator cylinder 31 by the first motor fixing bolt 27 and the second motor fixing bolt 53. The motor controller 29 is mounted on the right end face of the housing of the electric motor 28, the terminal of the electric motor 28 is connected to the drive output terminal of the motor controller 29, and the motor controller 29 is connected to the brake system controller to receive commands from the brake system controller. The limit switch 22 is installed at the central position of the rear cover 46, the limit switch 22 transmits the collected signal to the motor controller 29 through a limit switch signal wire 26, the limit switch 22 is a small-stroke microswitch, and when the screw mandrel 23 returns to the initial position, the screw mandrel 23 contacts with the limit switch 22 to generate a corresponding signal. The driving gear 25 is sleeved on an output shaft of the motor 28 and is in interference fit connection, and the driving gear 25 is in tooth meshing connection with the toothed internal circulation nut 19 on the outer circumferential surface. The toothed internal circulation nut 19 is sleeved on a screw rod at the left end of the screw rod ejector rod 23, a ball 24 is arranged in a spiral raceway on a central through hole of the toothed internal circulation nut 19 and a spiral raceway on the screw rod in the screw rod ejector rod 23, the ball 24 can circulate through a circulation raceway (not shown in the figure) in the toothed internal circulation nut 19, and the rotary motion of the toothed internal circulation nut 19 is converted into the linear motion of the screw rod ejector rod 23 through the ball 24. The toothed internal circulation nut 19 is installed between the rear cover 46 and the partition plate 44 through the first thrust bearing 21 and the second thrust bearing 20, a second thrust bearing 20 is sleeved on a boss at the right end of the toothed internal circulation nut 19 and is in contact connection, the right end face of the toothed internal circulation nut 19 is in contact connection with the left end face of the second thrust bearing 20, the second thrust bearing 20 is sleeved on a circular boss at the left end face of the partition plate 44 and is in contact connection, the right end face of the second thrust bearing 20 is in contact connection with the left end face of the partition plate 44, the left end face of the toothed internal circulation nut 19 is in contact connection with the right end face of the first thrust bearing 21, the first thrust bearing 21 is sleeved on a circular boss at the inner side of the rear cover 46 and is in contact connection, and the left end face of the first thrust bearing 21 is in contact connection with the end face of the rear cover 46. The right slide bar part of the screw mandrel 23 passes through the upper eccentric circular hole on the partition 44 and the circular hole on the third piston 35, and has a certain clearance with the two. The screw mandrel 23 can contact the third piston 35 during pressurization, but does not contact the partition 44. When the screw jack 23 returns to the initial position, there is no interference with the movement of the third piston 35. The simulator cylinder 31 is mounted on the right end face of the partition 44 by three bolts, the left end face of the simulator cylinder 31 is in contact connection with the right end face of the partition 44, and the three bolts are a first partition connecting bolt 60, a second partition connecting bolt 43 and a third partition connecting bolt 55, respectively. The rear cover 46 is mounted on the left end surface of the partition 44 by seven rivets, the right end surface of the rear cover 46 is in contact connection with the left end surface of the partition 44, and the seven rivets are a first rear cover connecting rivet 61, a second rear cover connecting rivet 59, a third rear cover connecting rivet 58, a fourth rear cover connecting rivet 45, a fifth rear cover connecting rivet 57, a sixth rear cover connecting rivet 56, and a seventh rear cover connecting rivet 54, respectively. Wherein: the rotation axes of the first piston 34, the second piston 40, the third piston 35, the third piston spring seat 38, the lead screw ejector rod 23, the toothed internal circulation nut 19, the first thrust bearing 21, the second thrust bearing 20 and the simulator cylinder 31 are collinear, the rotation axis of the output shaft of the motor 28 is collinear with the rotation axis of the driving gear 25, and the rotation axis of the output shaft of the motor 28 is parallel to the rotation axes of the first piston 34, the second piston 40, the third piston 35, the third piston spring seat 38, the lead screw ejector rod 23, the toothed internal circulation nut 19, the first thrust bearing 21, the second thrust bearing 20 and the simulator cylinder 31. The port a of the simulator electromagnetic valve 49, the port p of the simulator third liquid outlet electromagnetic valve 48 and the port a of the simulator one-way valve 47 are all connected with the oil inlet and outlet hole 33 hydraulic pipeline on the simulator cylinder 31, a port p of the simulator electromagnetic valve 49 and a port p of the simulator first liquid outlet electromagnetic valve 50 are connected with a port D hydraulic pipeline of the active brake pedal stroke simulator 12, a port a of the simulator first liquid outlet electromagnetic valve 50 is connected with a port G hydraulic pipeline of the active brake pedal stroke simulator 12, a port p of the simulator second liquid outlet electromagnetic valve 51 and a brake master cylinder pressure sensor 52 are connected with a port E hydraulic pipeline of the active brake pedal stroke simulator 12, a port a of the simulator second liquid outlet electromagnetic valve 51 is connected with a port H hydraulic pipeline of the active brake pedal stroke simulator 12, and a port a of the simulator third liquid outlet electromagnetic valve 48 and a port p of the simulator one-way valve 47 are connected with a port F hydraulic pipeline of the active brake pedal stroke simulator 12.

Referring to fig. 4, the main power supply device 13 includes an electric hydraulic cylinder, an electric hydraulic cylinder pressure sensor 62, an electric hydraulic cylinder first liquid outlet electromagnetic valve 63, and an electric hydraulic cylinder second liquid outlet electromagnetic valve 64.

The specific specifications and functions are as follows: the main energy supply device 13 is mainly used as a brake system energy supply device to realize the functions of active pressurization, pressure maintaining and active pressure reduction.

The electric hydraulic cylinder comprises an electric hydraulic cylinder body 65, an electric hydraulic cylinder piston spring 66, an electric hydraulic cylinder piston 67, an electric hydraulic cylinder ball screw 68 and an electric hydraulic cylinder motor 69; the cylinder body 65 of the electric hydraulic cylinder is a cylindrical structural member, the left end and the right end of the cylinder body are both provided with holes, the diameter of the left end opening is smaller and is processed into a threaded hole, the hole is an oil inlet and outlet hole a of the electric hydraulic cylinder, the diameter of the right end opening is larger, and an oil inlet and outlet hole p is formed in the outer cylindrical surface of the cylinder body 65 of the electric hydraulic cylinder; a center hole is formed in the center of the right end of the electric hydraulic cylinder piston 67, a spiral raceway for mounting balls is formed in the inner cylindrical surface of the center hole, and a spiral raceway matched with the spiral raceway of the electric hydraulic cylinder piston 67 is formed in the electric hydraulic cylinder ball screw 68; the electric hydraulic cylinder piston spring 66 and the electric hydraulic cylinder piston 67 are sequentially arranged in the electric hydraulic cylinder body 65, the electric hydraulic cylinder piston 67 is in sliding connection with the electric hydraulic cylinder body 65, the left end of the electric hydraulic cylinder ball screw 68 is arranged in a central hole at the right end of the electric hydraulic cylinder piston 67 and is in rolling connection, the right end of the electric hydraulic cylinder ball screw 68 is connected with an electric hydraulic cylinder motor 69 through a transmission mechanism (not shown in the figure), and the electric hydraulic cylinder ball screw 68 can convert the rotary motion of the electric hydraulic cylinder motor 69 into the linear motion of the electric hydraulic cylinder piston 67.

The electric hydraulic cylinder pressure sensor 62 adopts an active pressure sensor of type 303 manufactured by BOSCH company, needs to input a supply voltage of 5V, and can measure the pressure of the primary energy supply device 13.

The first liquid outlet electromagnetic valve 63 and the second liquid outlet electromagnetic valve 64 of the electric hydraulic cylinder are two-position two-way normally closed electromagnetic valves, so that the bidirectional flow of brake liquid can be realized, and the two-position two-way normally closed electromagnetic valves are used for controlling the on-off of the main energy supply device 13 and the hydraulic pressure adjusting unit 14.

The position and the connection mode of the specific parts are as follows: the port p of the first liquid outlet electromagnetic valve 63 of the electric hydraulic cylinder, the port p of the second liquid outlet electromagnetic valve 64 of the electric hydraulic cylinder, and the electric hydraulic cylinder pressure sensor 62 are all connected with the hydraulic pipeline a of the oil inlet and outlet hole of the electric hydraulic cylinder, the port a of the first liquid outlet electromagnetic valve 63 of the electric hydraulic cylinder is connected with the hydraulic pipeline I of the main energy supply device 13, the port a of the second liquid outlet electromagnetic valve 64 of the electric hydraulic cylinder is connected with the hydraulic pipeline J of the main energy supply device 13, and the oil inlet and outlet hole p of the electric hydraulic cylinder is connected with the hydraulic pipeline K of the main energy supply device 13.

Referring to fig. 5, the hydraulic pressure adjusting unit 14 includes a right rear wheel check valve 70, a right rear wheel liquid inlet solenoid valve 71, a left front wheel check valve 72, a left front wheel liquid inlet solenoid valve 73, a right front wheel check valve 74, a right front wheel liquid inlet solenoid valve 75, a left rear wheel check valve 76, a left rear wheel liquid inlet solenoid valve 77, a right rear wheel liquid outlet solenoid valve 78, a left front wheel liquid outlet solenoid valve 79, a right front wheel liquid outlet solenoid valve 80, and a left rear wheel liquid outlet solenoid valve 81.

The specific specifications and functions are as follows: the hydraulic pressure adjusting unit 14 has a function of adjusting the brake cylinder pressure.

The right rear wheel liquid inlet electromagnetic valve 71, the left front wheel liquid inlet electromagnetic valve 73, the right front wheel liquid inlet electromagnetic valve 75 and the left rear wheel liquid inlet electromagnetic valve 77 are two-position two-way normally open electromagnetic valves and respectively control the pressurization of the right rear wheel 15, the left front wheel 16, the right front wheel 17 and the left rear wheel 18.

The right rear wheel liquid outlet electromagnetic valve 78, the left front wheel liquid outlet electromagnetic valve 79, the right front wheel liquid outlet electromagnetic valve 80 and the left rear wheel liquid outlet electromagnetic valve 81 are two-position two-way normally closed electromagnetic valves and respectively control the pressure reduction of the right rear wheel 15, the left front wheel 16, the right front wheel 17 and the left rear wheel 18.

The right rear wheel check valve 70, the left front wheel check valve 72, the right front wheel check valve 74, and the left rear wheel check valve 76 define that the brake fluid can flow only in one direction.

The position and the connection mode of the specific parts are as follows: an opening a of the right rear wheel check valve 70, an opening P of the right rear wheel liquid inlet electromagnetic valve 71, an opening a of the left front wheel check valve 72 and an opening P of the left front wheel liquid inlet electromagnetic valve 73 are all connected with an M-opening hydraulic pipeline of the hydraulic adjusting unit 14, an opening a of the right front wheel check valve 74, an opening P of the right front wheel liquid inlet electromagnetic valve 75, an opening a of the left rear wheel check valve 76 and an opening P of the left rear wheel liquid inlet electromagnetic valve 77 are all connected with an L-opening hydraulic pipeline of the hydraulic adjusting unit 14, an opening P of the right rear wheel check valve 70, an opening a of the right rear wheel liquid inlet electromagnetic valve 71 and an opening P of the right rear wheel liquid outlet electromagnetic valve 78 are all connected with a Q-opening hydraulic pipeline of the hydraulic adjusting unit 14, an opening P of the left front wheel check valve 72, an opening a opening of the left front wheel liquid inlet electromagnetic valve 73 and an opening P of the left front wheel liquid outlet electromagnetic valve 79 are all connected with a P-opening hydraulic pipeline of the hydraulic adjusting unit 14, an opening P of the right rear wheel check valve 74, an opening a opening of the right front wheel liquid inlet electromagnetic valve 75, an opening of the right front wheel liquid inlet electromagnetic valve 75 and an opening P of the right front wheel liquid inlet electromagnetic valve 74, The p port of the right front wheel liquid outlet electromagnetic valve 80 is connected with an O port hydraulic pipeline of the hydraulic adjusting unit 14, the p port of the left rear wheel check valve 76, the a port of the left rear wheel liquid inlet electromagnetic valve 77 and the p port of the left rear wheel liquid outlet electromagnetic valve 81 are connected with an N port hydraulic pipeline of the hydraulic adjusting unit 14, and the a port of the right rear wheel liquid outlet electromagnetic valve 78, the a port of the left front wheel liquid outlet electromagnetic valve 79, the a port of the right front wheel liquid outlet electromagnetic valve 80 and the a port of the left rear wheel liquid outlet electromagnetic valve 81 are connected with an R port hydraulic pipeline of the hydraulic adjusting unit 14.

A brake operating mechanism 1, active brake pedal stroke simulator 12, main energy supply device 13 and the hydraulic pressure regulating unit 14 of by-wire braking system with backup function between the connection relation be: the driver directly controls the brake control mechanism 1, finally the hydraulic adjusting unit 14 controls the wheels to brake, and an active brake pedal stroke simulator 12 and a main energy supply device 13 are arranged between the output end of the brake control mechanism 1 and the input end of the hydraulic adjusting unit 14 in parallel. The output end of the brake control mechanism 1 comprises a first cavity liquid outlet A of the brake master cylinder, a second cavity liquid outlet B of the brake master cylinder and a third cavity liquid inlet C of the brake master cylinder, the first cavity liquid outlet A of the brake master cylinder is connected with a liquid inlet D brake pipeline of the active brake pedal stroke simulator 12, the second cavity liquid outlet B of the brake master cylinder is connected with a liquid inlet E brake pipeline of the active brake pedal stroke simulator 12, a third cavity liquid inlet C of the brake master cylinder is connected with a liquid outlet F brake pipeline of the active brake pedal stroke simulator 12, a liquid outlet G of the active brake pedal stroke simulator 12 and a liquid outlet I of the main energy supply device 13 are both connected with a liquid inlet M brake pipeline of the hydraulic adjusting unit 14, a liquid outlet H of the active brake pedal stroke simulator 12 and a liquid outlet J of the main energy supply device 13 are both connected with a liquid inlet L brake pipeline of the hydraulic adjusting unit 14, the liquid inlet K of the main energy supply device 13 and the liquid outlet R of the hydraulic adjusting unit 14 are connected with the liquid outlet d of the liquid storage tank 2 through brake pipelines.

Claims

1. The brake-by-wire system with the backup function is characterized by comprising a brake control mechanism (1), an active brake pedal stroke simulator (12), a main energy supply device (13) and a hydraulic pressure adjusting unit (14);

the brake control mechanism (1) comprises a brake master cylinder and a liquid storage tank (2);

the brake master cylinder is internally provided with three cavities which are arranged in series, namely a cavity I, a cavity II and a cavity III from left to right, wherein a cavity I liquid outlet A of the cavity I of the brake master cylinder is connected with a brake pipeline of a liquid inlet D of the active brake pedal stroke simulator (12), a cavity II liquid outlet B of the brake master cylinder is connected with a brake pipeline of a liquid inlet E of the active brake pedal stroke simulator (12), a cavity III liquid inlet C of the brake master cylinder is connected with a brake pipeline of a liquid outlet F of the active brake pedal stroke simulator (12), a liquid outlet G of the active brake pedal stroke simulator (12) and a liquid outlet I of the main energy supply device (13) are both connected with a brake pipeline of a liquid inlet M of the hydraulic adjusting unit (14), a liquid outlet H of the active brake pedal stroke simulator (12) and a liquid outlet J of the main energy supply device (13) are both connected with a brake pipeline of a liquid inlet L of the hydraulic adjusting unit (14), a liquid inlet K of the main energy supply device (13) and a liquid outlet R of the hydraulic adjusting unit (14) are both connected with a liquid outlet d of the liquid storage tank (2) through a brake pipeline.

2. The brake-by-wire system with backup function according to claim 1, wherein the brake master cylinder comprises a brake master cylinder body (7), a brake master cylinder first piston (10), a brake master cylinder second piston (8), a brake master cylinder first piston spring (11), a brake master cylinder second piston spring (9) and a brake master cylinder push rod (4), the brake master cylinder body (7) is a cylindrical structural member, the left end of the brake master cylinder body is closed, the right end of the brake master cylinder body is opened, a flange plate is arranged on the right end surface of the brake master cylinder, six liquid inlet and outlet ports are arranged on the outer cylindrical surface of the brake master cylinder body (7) and are all threaded holes, the brake master cylinder first piston spring (11), the brake master cylinder first piston (10), the brake master cylinder second piston spring (9), the brake master cylinder second piston (8) and the brake master cylinder push rod (4) are sequentially arranged in the brake master cylinder body (7), the brake master cylinder comprises a first piston (10) of the brake master cylinder, a second piston (8) of the brake master cylinder and a cylinder body (7) of the brake master cylinder, wherein the first piston spring (11) of the brake master cylinder, the first piston (10) of the brake master cylinder, a second piston spring (9) of the brake master cylinder, the second piston (8) of the brake master cylinder, a push rod (4) of the brake master cylinder and the rotation axis of the cylinder body (7) of the brake master cylinder are collinear, three chambers which are isolated by the first piston (10) of the brake master cylinder and the second piston (8) of the brake master cylinder and can independently generate high-pressure brake fluid are arranged in the brake master cylinder in a series manner, and are a first chamber, a second chamber and a third chamber from left to right in sequence, a push rod (4) of the brake master cylinder is arranged at a mechanical inlet of the brake master cylinder, and the brake master cylinder is fixed on a vehicle body through a flange;

liquid storage pot (2) total four liquid outlets, be liquid outlet f, liquid outlet r, liquid outlet t and liquid outlet d respectively, liquid outlet f, liquid outlet r, liquid outlet t are connected through pipeline and I cavity inlet a of brake master cylinder, II cavity inlet b of brake master cylinder, III cavity inlet c of brake master cylinder respectively, liquid storage pot (2) are installed in the top of brake master cylinder.

3. The brake-by-wire system with backup function according to claim 1, wherein said brake operating mechanism (1) further comprises a brake pedal (6), a pedal displacement sensor (5), a master cylinder check valve (3);

brake pedal (6) install driver front portion below in the carriage, the top of rotation part is fixed on the pedal support through the round pin axle in brake pedal (6), the pedal support passes through the bolt fastening on the automobile body, the middle-end left surface of rotation part is connected with the right-hand member face contact of brake master cylinder push rod (4) in the brake master cylinder in brake pedal (6), pedal displacement sensor (5) are fixed on the pedal support of being connected with the automobile body, the digging arm of pedal displacement sensor (5) is connected with the rotation part in brake pedal (6), install between liquid storage pot (2) liquid outlet t and brake master cylinder III cavity inlet c brake master cylinder check valve (3), the p mouth and the liquid storage pot (2) liquid outlet t hydraulic line connection of brake master cylinder check valve (3), the a mouth and the hydraulic line connection of brake master cylinder III cavity inlet c of brake master cylinder check valve (3).

4. The brake-by-wire system with a backup function according to claim 1, wherein the active brake pedal stroke simulator (12) comprises a motor controller (29), a motor (28), a driving gear (25), a toothed internal circulation nut (19), a ball (24), a screw rod ejector rod (23), a limit switch (22), a rear cover (46), a partition plate (44), a first thrust bearing (21), a second thrust bearing (20), a second piston (40), a second piston spring (41), a second piston sealing ring (30), a first piston (34), a first piston spring (36), a third piston (35), a third piston spring (37), a third piston spring seat (38), a third piston spring seat retainer ring (39), a third piston sealing ring (32), a simulator cylinder body (31), a simulator check valve (47), a first piston spring, a second piston spring (35), a third piston spring (37), a simulator cylinder seat (38), a simulator check valve (47), and a second piston sealing ring (20), A simulator third liquid outlet electromagnetic valve (48), a simulator electromagnetic valve (49), a simulator first liquid outlet electromagnetic valve (50), a simulator second liquid outlet electromagnetic valve (51) and a brake master cylinder pressure sensor (52);

the simulator is characterized in that the simulator cylinder body (31) is installed on the right end face of the partition plate (44) through a bolt, the rear cover (46) is installed on the left end face of the partition plate (44) through a rivet, the toothed internal circulation nut (19) is installed between the rear cover (46) and the partition plate (44) through a first thrust bearing (21) and a second thrust bearing (20), the left end face and the right end face of the first thrust bearing (21) are respectively in contact connection with the rear cover (46) and the toothed internal circulation nut (19), the left end face and the right end face of the second thrust bearing (20) are respectively in contact connection with the toothed internal circulation nut (19) and the partition plate (44), the left end raceway of the lead screw ejector rod (23) is in rolling connection by adopting a ball (24) to be installed in a spiral raceway of a center hole of the toothed internal circulation nut (19), the right end of the lead screw ejector rod (23) is inserted into a stepped hole of the simulator cylinder body (31), and a third piston (35) is sleeved at the right end of the lead screw ejector rod (23), the left end of a third piston (35) is sleeved in a second piston (40), the right end of the third piston (35) is sleeved on the first piston (34) and is in sliding connection with the first piston (34), the first piston (34) and the second piston (40) are sequentially arranged in a first section of stepped hole and a second section of stepped hole of a simulator cylinder body (31) and are in sliding connection with each other, a first piston spring (36) is sleeved on a circular boss on the second end face on the left side of the first piston (34), a second piston spring (41) and a third piston spring (37) are respectively arranged on a left end shaft of the second piston (40) and a left end shaft of the third piston (35), a third piston spring seat (38) is sleeved on the left end of the third piston (35) in transition fit, a third piston spring seat (39) is arranged in a circular groove on the left end of the third piston (35), the left end face of the third piston spring seat (38) is in contact connection with the right end face of the third piston spring seat (39), a second piston sealing ring (30) and a third piston sealing ring (32) are respectively sleeved in annular grooves of a second piston (40) and a third piston (35), a motor (28) is installed on the right end face of a partition plate (44) below a simulator cylinder body (31), a driving gear (25) is sleeved on an output shaft of the motor (28) and is in interference fit connection, the driving gear (25) is in meshing connection with a toothed internal circulation nut (19), a motor controller (29) is installed on the right end face of a shell of the motor (28), the motor (28) is in electric wire connection with the motor controller (29), a limit switch (22) is installed at the central position of a rear cover (46), the limit switch (22) is connected with the motor controller electromagnetic valve (29) through a limit switch signal wire (26), an a port of a simulator (49) and a p port of a third liquid outlet electromagnetic valve (48) of the simulator, An a port of a simulator one-way valve (47) is connected with a hydraulic pipeline of an oil inlet and outlet hole (33) on a simulator cylinder body (31), a p port of a simulator electromagnetic valve (49) and a p port of a simulator first liquid outlet electromagnetic valve (50) are connected with a D port hydraulic pipeline of an active brake pedal stroke simulator (12), an a port of the simulator first liquid outlet electromagnetic valve (50) is connected with a G port hydraulic pipeline of the active brake pedal stroke simulator (12), a p port of a simulator second liquid outlet electromagnetic valve (51) and a brake master cylinder pressure sensor (52) are connected with an E port hydraulic pipeline of the active brake pedal stroke simulator (12), an a port of the simulator second liquid outlet electromagnetic valve (51) is connected with an H port hydraulic pipeline of the active brake pedal stroke simulator (12), an a port of a simulator third liquid outlet electromagnetic valve (48) and a p port of the simulator one-way valve (47) are connected with an F port hydraulic pipeline of the active brake pedal stroke simulator (12) .

5. The brake-by-wire system with backup function according to claim 4, wherein the simulator cylinder (31) is a cylindrical structure, the left end and the right end of the simulator cylinder are both open, a flange plate for installation is arranged on the outer cylindrical surface of the left end cylinder opening, three bolt holes are uniformly distributed on the flange plate, a three-section cylindrical stepped hole is processed along the central axis of the simulator cylinder (31), the diameter of the three-section stepped hole is gradually decreased from left to right, and is a first-section stepped hole, a second-section stepped hole and a third-section stepped hole in sequence, wherein the second piston (40) and the second piston spring (41) are installed in the first-section stepped hole, the first piston (34) and the first piston spring (36) are installed in the second-section stepped hole, the third-section stepped hole is an oil inlet/outlet hole (33) of the simulator cylinder (31) and is processed into an internal threaded hole, the cylinder wall of the first section of stepped hole is also provided with a vent hole (42), the three-section cylindrical stepped holes are mutually communicated and the rotation axes are collinear;

the third piston (35) is a two-section stepped shaft, the right end shaft diameter is larger, an annular groove for placing a sealing ring is processed on the cylindrical surface of the right end shaft, the left end shaft diameter is smaller and used for mounting a third piston spring (37), a circular groove for placing a third piston spring seat check ring (39) is processed on the cylindrical surface of the left end shaft, a circular hole is processed on the left end shaft along the rotation center line of the stepped shaft, and the diameter of the circular hole is slightly larger than that of a right end slide bar of the screw mandrel (23); the first piston (34) is a two-section stepped shaft, the shaft diameter of the right end is larger, the shaft diameter of the left end is smaller, the shaft diameter of the left end is used for mounting a third piston spring (37), a circular boss is arranged on the left end face of the shaft with the larger diameter and used for mounting the first piston spring (36), a circular stepped hole is machined along the rotation center line of the stepped shaft, the diameter of the right end of the stepped hole is larger and is equal to the shaft diameter of the right end of the third piston (35), and the diameter of the left end of the stepped hole is smaller and is equal to the shaft diameter of the left end of the third piston (35); the second piston (40) is a two-section type stepped shaft, the right end shaft diameter is large, a circular ring-shaped boss is arranged on the right end face and used for mounting a first piston spring (36), an annular groove used for placing a sealing ring is processed on the cylindrical surface of the right end shaft, the left end shaft diameter is small and used for mounting a second piston spring (41), a circular through hole is processed along the rotation center line of the stepped shaft, and the diameter of the through hole is slightly larger than that of the left end shaft diameter of the first piston (34).

6. The brake-by-wire system with a backup function according to claim 1, wherein the main energy supply device (13) comprises an electric hydraulic cylinder, an electric hydraulic cylinder pressure sensor (62), an electric hydraulic cylinder first fluid outlet solenoid valve (63), and an electric hydraulic cylinder second fluid outlet solenoid valve (64);

the electric hydraulic cylinder comprises an electric hydraulic cylinder body (65), an electric hydraulic cylinder piston spring (66), an electric hydraulic cylinder piston (67), an electric hydraulic cylinder ball screw (68) and an electric hydraulic cylinder motor (69); the cylinder body (65) of the electric hydraulic cylinder is a cylindrical structural member, the left end and the right end of the cylinder body are both provided with holes, the diameter of the left end opening is smaller and is processed into a threaded hole, the hole is an oil inlet and outlet hole a of the electric hydraulic cylinder, the diameter of the right end opening is larger, and an oil inlet and outlet hole p is formed in the outer cylindrical surface of the cylinder body (65) of the electric hydraulic cylinder; a center hole is formed in the center of the right end of the electric hydraulic cylinder piston (67), a spiral raceway for mounting balls is formed in the inner cylindrical surface of the center hole, and a spiral raceway matched with the spiral raceway of the electric hydraulic cylinder piston (67) is formed in the electric hydraulic cylinder ball screw (68); the electric hydraulic cylinder piston spring (66) and the electric hydraulic cylinder piston (67) are sequentially arranged in the electric hydraulic cylinder body (65), the electric hydraulic cylinder piston (67) is in sliding connection with the electric hydraulic cylinder body (65), the left end of the electric hydraulic cylinder ball screw (68) is arranged in a central hole at the right end of the electric hydraulic cylinder piston (67) and is in rolling connection, the right end of the electric hydraulic cylinder ball screw (68) is connected with an electric hydraulic cylinder motor (69) through a transmission mechanism, and the electric hydraulic cylinder ball screw (68) can convert the rotary motion of the electric hydraulic cylinder motor (69) into the linear motion of the electric hydraulic cylinder piston (67);

the hydraulic control system is characterized in that a p port of the first liquid outlet electromagnetic valve (63) of the electric hydraulic cylinder, a p port of the second liquid outlet electromagnetic valve (64) of the electric hydraulic cylinder, and a pressure sensor (62) of the electric hydraulic cylinder are connected with a hydraulic pipeline of an oil inlet and outlet hole a of the electric hydraulic cylinder, an a port of the first liquid outlet electromagnetic valve (63) of the electric hydraulic cylinder is connected with a hydraulic pipeline of an I port of the main energy supply device (13), an a port of the second liquid outlet electromagnetic valve (64) of the electric hydraulic cylinder is connected with a hydraulic pipeline of a J port of the main energy supply device (13), and an oil inlet and outlet hole p of the electric hydraulic cylinder is connected with a hydraulic pipeline of a K port of the main energy supply device (13).

7. The brake-by-wire system with backup function according to claim 1, wherein the hydraulic pressure adjusting unit (14) comprises a right rear wheel check valve (70), a right rear wheel liquid inlet solenoid valve (71), a left front wheel check valve (72), a left front wheel liquid inlet solenoid valve (73), a right front wheel check valve (74), a right front wheel liquid inlet solenoid valve (75), a left rear wheel check valve (76), a left rear wheel liquid inlet solenoid valve (77), a right rear wheel liquid outlet solenoid valve (78), a left front wheel liquid outlet solenoid valve (79), a right front wheel liquid outlet solenoid valve (80), and a left rear wheel liquid outlet solenoid valve (81);

an opening a of the right rear wheel check valve (70), an opening P of the right rear wheel liquid inlet electromagnetic valve (71), an opening a of the left front wheel check valve (72) and an opening P of the left front wheel liquid inlet electromagnetic valve (73) are all connected with an M opening hydraulic pipeline of the hydraulic adjusting unit (14), an opening a of the right front wheel check valve (74), an opening P of the right front wheel liquid inlet electromagnetic valve (75), an opening a of the left rear wheel check valve (76) and an opening P of the left rear wheel liquid inlet electromagnetic valve (77) are all connected with an L opening hydraulic pipeline of the hydraulic adjusting unit (14), an opening P of the right rear wheel check valve (70), an opening a of the right rear wheel liquid inlet electromagnetic valve (71) and an opening P of the right rear wheel liquid outlet electromagnetic valve (78) are all connected with a Q opening hydraulic pipeline of the hydraulic adjusting unit (14), an opening P of the left front wheel check valve (72), an opening a opening of the left front wheel liquid inlet electromagnetic valve (73) and an opening P of the left front wheel liquid outlet electromagnetic valve (79) are all connected with a P opening hydraulic pipeline of the hydraulic adjusting unit (14), the port p of the right front wheel check valve (74), the port a of the right front wheel liquid inlet electromagnetic valve (75) and the port p of the right front wheel liquid outlet electromagnetic valve (80) are all connected with an O port hydraulic pipeline of the hydraulic adjusting unit (14), the port p of the left rear wheel check valve (76), the port a of the left rear wheel liquid inlet electromagnetic valve (77) and the port p of the left rear wheel liquid outlet electromagnetic valve (81) are all connected with an N port hydraulic pipeline of the hydraulic adjusting unit (14), and the port a of the right rear wheel liquid outlet electromagnetic valve (78), the port a of the left front wheel liquid outlet electromagnetic valve (79), the port a of the right front wheel liquid outlet electromagnetic valve (80) and the port a of the left rear wheel liquid outlet electromagnetic valve (81) are all connected with an R port hydraulic pipeline of the hydraulic adjusting unit (14).