CN104442779B - Movement conversion mechanism and actively the Multifunctional brake system of regulation are turned round with slowing down to increase - Google Patents

Abstract

The invention belongs to the technical field of motor vehicle braking, and specifically relates to a multifunctional braking system with a deceleration and increasing torsion motion conversion mechanism and active adjustment, and aims to provide a system with compact structure, convenient layout and simple structure. It is characterized in that it also includes a brake outer casing (21), a brake pedal simulator, a brake master cylinder (3) and a motion conversion mechanism. The invention cancels the vacuum booster, cancels the mechanical connection between the brake pedal and the hydraulic chamber, effectively reduces the overall mass, has a compact structure and is easy to arrange. The complexity of the structure is greatly reduced, and the cost is reduced. By using the motor as the power source, that is, using mechanical and electrical connections, the signal transmission is fast and the braking response is fast. By adopting the brake backup of the mechanical structure, when the electrical structure fails, the backup structure can quickly intervene to produce a certain braking effect and ensure the driving safety.

Description

Multifunctional braking system with deceleration and torque increasing motion conversion mechanism and active adjustment

technical field

The invention belongs to the technical field of motor vehicle braking, and in particular relates to a multifunctional braking system with a decelerating and increasing torsion motion conversion mechanism and active adjustment.

Background technique

When a traditional car brakes, the driver usually steps on the brake pedal, and with the help of a series of mechanical structures and a vacuum booster, the oil in the brake master cylinder flows into each wheel cylinder through the brake pipeline at a certain pressure. , and finally drive the disc or drum brake to complete the braking action, so as to achieve wheel braking. However, with the increase of high-grade highways and the increase of the average speed of automobiles, coupled with the increase in the number of automobiles, in order to improve the driving safety of automobiles, domestic and foreign related enterprises and scientific research institutions have developed a series of active systems such as ABS, TCS, and ESP. security system. When traditional braking systems integrate such active safety systems, additional control units and hardware need to be added, making the entire braking system complex and redundant.

At the beginning of the 20th century, some foreign research institutes and company groups explored and researched the new model of the braking system, invested considerable manpower, material and financial resources, and achieved some phased results. Such as EMB, EHB, etc., but the EMB system uses a large number of electronic devices, so the backup when the brake fails is too complicated and the cost is too high; the number of solenoid valves used in EHB is too many, and the hydraulic pipeline is too cumbersome, making the system too complex.

Contents of the invention

The purpose of the present invention is to provide a compact structure, convenient layout, simple structure, multifunctional brake system with deceleration and torque increase motion conversion mechanism and active adjustment.

The present invention is achieved like this:

A multi-functional brake system with a deceleration, increase and torque conversion mechanism and active adjustment, including a brake housing, a motor, a brake pedal simulator, a brake master cylinder, a motion conversion mechanism, a hydraulic source, a solenoid valve and a brake wheel Cylinder; the brake pedal simulator is connected to the front part of the brake outer shell, the brake pedal simulator is used to simulate the braking feeling and obtain the driver's braking intention, and is used to achieve wheel braking when the motor fails; the brake outer shell is a cylinder shape, the rear section of the brake housing is connected to the motion conversion mechanism; the motor is installed on the brake master cylinder, connected to the electronic control unit and the motion conversion mechanism respectively, and rotates under the control of the electronic control unit to provide power for the motion conversion mechanism The motion conversion mechanism is also connected with the brake master cylinder, which converts the rotation of the motor into a linear motion, and drives the brake master cylinder to realize wheel braking; driven by the motion conversion mechanism, the brake master cylinder provides hydraulic pressure for automobile braking; The hydraulic pressure source is connected to the solenoid valve to compensate for hydraulic leakage; the brake wheel cylinder is connected to the brake master cylinder through the solenoid valve, and under the control of the electronic control unit, it provides power for the wheels to achieve braking.

The above-mentioned pedal simulator is integrally installed in the front section of the brake housing, and maintains a gap of 20-30 mm with the master cylinder piston push rod.

The above-mentioned pedal simulator includes a brake pedal, a pedal push rod, a simulator end face, a simulator kingpin shaft, a simulator outer shell, a sleeve, a damping element, a pedal displacement sensor and a pedal simulator damping spring; the brake pedal It is connected with the front end of the pedal push rod by bolts, and drives the pedal push rod to move when the driver steps on it; the end face of the simulator is disc-shaped, with a through hole in the center, and is fixedly connected with the front end of the sleeve; the sleeve is a cylinder There is a tapered hole on the front end surface, and a snap ring is provided on the outside of the middle part. The front end of the snap ring is on the front inner wall of the simulator shell, and a blind hole is opened in the middle part of the rear section as the simulator kingpin shaft installation hole. ; The rear end of the pedal push rod is connected to the front end of the sleeve through the through hole in the middle part of the end face of the simulator; the simulator shell is a cylindrical shape with openings at both ends, and the dimensions of the openings at the front and rear ends are respectively the same as the outer diameter of the sleeve and The outer diameter of the rear end of the kingpin shaft of the simulator is the same, and there is a threaded hole at the rear end as the long rod installation hole at the left end of the locking piston; the kingpin shaft of the simulator is a cylinder, the front part is installed in the through hole in the middle of the sleeve, and the rear The outer diameter of the end is 3~5mm smaller than the outer diameter of the main part of the kingpin shaft of the simulator, and the rear end is installed in the opening at the rear end of the simulator housing, and a circular groove is opened in the center of the end surface of the rear end as a mounting hole for the damping element; the pedal The simulator damping spring is set outside the sleeve and the simulator kingpin shaft, the front end is against the rear end face of the sleeve snap ring, and the rear end is against the inner wall of the rear end of the simulator housing, providing a reaction force for the driver to brake To simulate the braking feeling of a traditional car; the pedal displacement sensor is connected to the lever of the brake pedal through the bracket, and is fixedly installed on the bottom end surface of the simulator housing. The pedal displacement sensor collects the pedal displacement signal and sends the signal to the electronic control Unit; the damping element is installed in the damping element installation hole at the rear end of the kingpin shaft of the simulator, corresponding to the installation position of the piston push rod.

The motor mentioned above is implemented by a brushless DC motor, the stall torque of the motor is 4NM, the idling speed can reach 2000rpm within 4ms, and the overall moment of inertia of the motor is on the order of 10 ⁻⁵ .

The above-mentioned brake master cylinder adopts a plunger-type master cylinder structure, and the brake master cylinder piston is installed in the brake master cylinder. The brake master cylinder piston includes a front chamber piston and a rear chamber piston; the front chamber piston and the rear chamber piston The brake master cylinder is divided into two independent hydraulic chambers; the front end of the piston spring in the rear chamber is pressed against the inner wall of the closed end of the piston in the rear chamber, and the rear end is pressed against the inner wall of the closed end of the brake master cylinder; the piston spring in the front chamber is closed. There is a groove in the middle of the outer end surface of one end as the installation hole of the piston push rod, and the rear end of the piston push rod is installed in the installation hole of the piston push rod; the outer end surface of the closed end of the piston in the front cavity is connected to the movement conversion mechanism; the front end of the piston spring in the front cavity Push against the inner wall of the closed end of the piston in the front chamber, and the rear end of the piston spring in the front chamber pushes against the end face of the closed end of the piston in the rear chamber.

The above-mentioned motion conversion mechanism includes a motor output shaft gear and a ball screw pair; wherein, the motor output shaft gear is a pinion; the ball screw pair includes a ball screw, a ball and an outer nut of the ball screw; the ball screw is a hollow structure, There is a groove on its upper part as the installation hole of the screw pre-tightening mechanism, which is set on the outside of the piston push rod, and the rear end is pushed against the outer wall of the closed end of the piston in the front chamber; the outer nut of the ball screw is a convex shape with a narrow front and a wide rear. The platform structure, the outer wall is a gear structure, which is set on the outside of the ball screw, and the ball is sandwiched between the two. The rear end face is pressed against the end face of the opening end of the brake master cylinder and the end face of the closed end of the piston in the front cavity, and the output of the motor. The shaft gear meshes to form a gear pair.

It also includes deep groove ball bearings, which are set on the outside of the outer nut of the ball screw to limit the outer nut of the ball screw.

The hydraulic pressure source mentioned above is realized by a hydraulic accumulator, and the liquid outlet of the hydraulic accumulator passes through the hydraulic accumulator solenoid valve and the front chamber of the brake master cylinder, the rear chamber of the brake master cylinder, and the solenoid valve of the brake wheel cylinder. The input end is connected with the input end of the electromagnetic valve of the locking piston cavity; the output end of the electromagnetic valve of the brake wheel cylinder is connected with the input end of the brake wheel cylinder; the output end of the electromagnetic valve of the locking piston cavity is connected with the locking piston.

The screw pre-tensioning mechanism as described above includes a pre-tightening horizontal link, a pre-tightening spring, and a pre-tightening vertical link; the pre-tightening vertical link is rod-shaped, and a cylindrical through hole is opened on the top as a mounting hole for the tightening horizontal link. The bottom of the ball screw is directly inserted into the mounting hole of the screw preloading mechanism; the preloading horizontal link is a stepped cylindrical shape, and the left end is provided with a ring-shaped protrusion, and one end of the preloading horizontal link passes through the preloading vertical link. Tighten the connecting rod installation hole, installed on the inner wall of the rear end of the brake outer casing; the preload spring is set on the outside of the preloaded horizontal link, and is stuck between the inner wall of the rear end of the brake outer casing and the preloaded horizontal link, and the preloaded spring is compressed.

The locking piston chamber as described above includes a locking piston housing, a locking piston, and a damping spring; the locking piston housing is a closed cylinder, and the lower part of the front end is provided with a liquid outlet hole in the piston chamber, through which the liquid outlet hole in the piston chamber It is connected with the output end of the solenoid valve in the locking piston cavity, so that the liquid in the cavity is connected with the brake circuit; the left end of the locking piston is a long rod, and the big end of the piston is a rubber piston. The long rod at the left end of the locking piston is installed on the locking The left end of the piston is installed in the long rod installation hole; the damping spring is installed at the right end of the locking piston to play the role of guiding and damping, and the spring stiffness K is less than 5000N/m.

The beneficial effects of the present invention are:

The invention cancels the vacuum booster, cancels the mechanical connection between the brake pedal and the hydraulic chamber, effectively reduces the overall quality, has a compact structure and is easy to arrange. The complexity of the structure is greatly reduced, and the cost is reduced. By using the motor as the power source, that is, using mechanical and electrical connections, the signal transmission is fast and the braking response is fast. Differential braking is achieved by controlling solenoid valves and motors. The brake backup of the mechanical structure is very different from the general brake-by-wire system. When the electrical structure fails, the backup structure can quickly intervene to produce a certain braking effect, ensuring driving safety and meeting the requirements of braking regulations. .

In the present invention, the outer surface of the screw nut is processed into a gear, which is meshed with the output shaft gear of the motor to form a ball screw pair. On the basis of not adding other accessories, the torque requirement for the motor is reduced, and the torque of the motor is also reduced. The size makes the structure of the whole braking system simple. By using the hydraulic accumulator to compensate the hydraulic leakage of the braking system, the relative clearance of the push rod brake piston can be adjusted steplessly, which is simpler in structure and lower in cost than using a hydraulic liquid storage chamber.

Description of drawings

Fig. 1 is a structural schematic diagram of a multifunctional braking system with deceleration and torque increasing motion conversion mechanism and active adjustment of the present invention;

Fig. 2 is a schematic structural view of the preload mechanism in Fig. 1;

Fig. 3 is a schematic structural view of the locking piston in Fig. 1;

In the figure, 1. brake pedal, 2. motor, 3. brake master cylinder, 4. front cavity piston, 5. rear cavity piston, 6. hydraulic accumulator, 7. hydraulic accumulator solenoid valve, 8. Brake wheel cylinder solenoid valve, 9. Simulator housing, 10. Damping element, 11. Lead screw pretension mechanism, 12. Motor output shaft gear, 13. Ball screw, 14. Piston push rod, 15. Lock Piston chamber, 16. Deep groove ball bearing, 17. Ball screw nut, 18. Connecting pin, 19. Pedal displacement sensor, 20. Simulator end face, 21. Brake outer shell, 22. Pressure sensor, 23. Brake wheel Cylinder, 24. Pedal simulator damping spring, 25. Locking piston cavity solenoid valve, 26. Pedal push rod, 27. Sleeve, 28. Simulator king pin shaft, 29. Preload spring, 30. Preload vertical connection Rod, 31. pre-tightening cross-link, 32. damping spring, 33. locking piston housing, 34. locking piston, 35. piston chamber liquid outlet, 36. dust cover.

detailed description

A multifunctional braking system with deceleration and torque increasing motion conversion mechanism and active adjustment of the present invention will be described below in conjunction with the accompanying drawings and specific embodiments:

As shown in Figure 1, a multifunctional braking system with a deceleration, increasing torsion motion conversion mechanism and active adjustment includes a brake outer shell 21, a motor 2, a brake pedal simulator, a brake master cylinder 3, a motion conversion mechanism, Hydraulic source, solenoid valve and brake wheel cylinder 23. The brake pedal simulator is connected with the front section of the brake outer shell 21, and it is used to simulate the braking feeling and obtain the driver's braking intention, and is used to realize wheel braking when the motor 2 fails. The brake housing 21 is cylindrical, and its rear section is connected with the motion conversion mechanism. Motor 2 is installed on the brake master cylinder 3, and it is connected with electronic control unit and motion conversion mechanism respectively, rotates under the control of electronic control unit, provides power for motion conversion mechanism. The rotation angle sensor is installed in the motor 2, collects the rotation angle information of the rotor of the motor, and sends the rotation angle information to the electronic control unit. The motion conversion mechanism is also connected with the brake master cylinder 3, and converts the rotation of the motor 2 into linear motion, and drives the brake master cylinder 3 to realize wheel braking. The brake master cylinder 3 provides hydraulic pressure for automobile braking under the drive of the motion conversion mechanism. The hydraulic source is connected with the solenoid valve to compensate hydraulic leakage. There are four brake wheel cylinders 23 in total, and the four brake wheel cylinders 23 are respectively connected with the brake master cylinder 3 through solenoid valves, and under the control of the electronic control unit, provide power for the wheels to achieve braking.

In this embodiment, the pedal simulator is integrally installed in the front section of the outer brake housing 21, and maintains a gap of 20-30 mm with the master cylinder piston push rod 14, such as 20 mm, 25 mm or 30 mm. The pedal simulator includes a brake pedal 1, a pedal push rod 26, a simulator end face 20, a sleeve 27, a simulator kingpin shaft 28, a simulator outer shell 9, a damping element 10, a pedal displacement sensor 19 and a pedal simulator damping spring twenty four. The front end of the brake pedal 1 and the pedal push rod 26 is connected by bolts, and the pedal push rod 26 is driven to move when the driver steps on it. The end face 20 of the simulator is disc-shaped, and its center has a through hole, which is fixedly connected with the front end of the sleeve 27 . The sleeve 27 is cylindrical, with a tapered hole on its front end face, and a snap ring on the outside of the middle part. The blind hole is used as the simulator kingpin shaft 28 installation hole, and the size of the blind hole is consistent with the outer diameter of the simulator kingpin shaft 28 . The rear end of the pedal push rod 26 passes through the through hole in the middle part of the end face 20 of the simulator and is connected with the front end of the sleeve 27 through a ball hinge. The simulator housing 9 is cylindrical with openings at both ends, and the dimensions of the openings at the front and rear ends are respectively consistent with the outer diameter of the sleeve 27 and the outer diameter of the rear end of the simulator kingpin shaft 28, and there are threads at its rear end. The hole is used as the long rod mounting hole at the left end of the locking piston. The simulator kingpin shaft 28 is a cylinder, its front part is installed in the through hole in the middle part of the sleeve 27, and the outer diameter of the rear end is 3-5mm smaller than the outer diameter of the main part of the simulator kingpin shaft 28, such as 3mm, 4mm or 5mm, the rear end is installed in the opening at the rear end of the simulator housing 9, and a circular groove is arranged at the center of the rear end face of the simulator kingpin shaft 28 as a damping element mounting hole. The pedal simulator damping spring 24 is sleeved outside the sleeve 27 and the simulator kingpin shaft 28, the front end is pushed against the rear end face of the sleeve 27 snap ring, and the rear end is pushed against the rear end inner wall of the simulator housing 9, which is Driver brakes provide reaction force to simulate the braking feel of a conventional car. The pedal displacement sensor 19 of the brake pedal simulator is connected with the lever of the brake pedal 1 through a bracket, and is fixedly installed on the bottom end surface of the simulator housing 9 . When the driver depresses the brake pedal 1, the pedal displacement sensor 19 will collect the pedal displacement signal and send the signal to the electronic control unit. The damping element 10 is installed in the damping element mounting hole at the rear end of the simulator kingpin shaft 28, corresponding to the installation position of the piston push rod 14. Once the motor 2 fails, the brake pedal simulator can move and push the piston push rod 14 to generate braking force. Brake pedal 1 and pedal push rod 26 are mature products, which can be purchased from the market. The simulator end face 20, the sleeve 27, the simulator kingpin shaft 28, and the simulator shell 9 are all made of No. 45 steel.

The damping element 10, the pedal displacement sensor 19 and the pedal simulator damping spring 24 are realized by using existing mature products.

Motor 2 is implemented by a brushless DC motor, and its torque and dynamic response need to match the requirements of the entire braking system. In this embodiment, the stall torque of the motor 2 is 4NM, the motor stall current cannot be too large, the response time is short, the idling speed can reach 2000rpm within 4ms, the forward and reverse switching time is short, and the overall moment of inertia of the motor is 10 ^{- 5} orders of magnitude.

The brake master cylinder 3 adopts a traditional plunger type master cylinder structure and is made of gray cast iron. The brake master cylinder piston is installed in the brake master cylinder 3, and it generates hydraulic pressure in the brake master cylinder 3 under the promotion of the motion conversion mechanism. The brake master cylinder piston includes a front cavity piston 4 and a rear cavity piston 5, and the front cavity piston 4 and the rear cavity piston 5 adopt a common piston structure. The front chamber piston 4 and the rear chamber piston 5 divide the brake master cylinder 3 into two independent hydraulic chambers. The front end of the rear chamber piston spring is pushed against the inner wall of the closed end of the rear chamber piston 5, and the rear end is pushed against the inner wall of the closed end of the brake master cylinder 3. The middle part of an end outer end face of front cavity piston 4 sealing has groove as piston push rod installation hole, and the rear end of piston push rod 14 is installed in the piston push rod installation hole. The closed outer end surface of the front chamber piston 4 is connected with the motion conversion mechanism. The front end of the front chamber piston spring pushes against the inner wall of the front chamber piston 4 closed one end, and the rear end of the front chamber piston spring pushes against the end face of the rear chamber piston 5 closed one end. In this embodiment, both the front chamber piston 4 and the rear chamber piston 5 are made of composite materials, such as copper-aluminum alloy.

The motion conversion mechanism includes a motor output shaft gear 12 and a ball screw pair. Wherein, the motor output shaft gear 12 is a pinion gear, which is made of 54 steel and processed by casting. The motor 2 output shaft and the gear are integrally structured. The ball screw pair includes a ball screw 13, balls and an outer nut 17 of the ball screw. The ball screw 13 is a hollow structure, and there is a groove on its upper part as the installation hole of the screw pretensioning mechanism. It is set on the outside of the piston push rod 14, and its rear end is against the outer wall of the closed end of the front chamber piston 4. . The outer nut 17 of the ball screw is a boss structure with a narrow front and a wide rear, and the outer wall is a gear structure. It is set on the outside of the ball screw 13, and the ball is sandwiched between the two. Its rear end faces against the brake master cylinder. 3 The end face of the open end and the end face of the closed end of the front chamber piston 4, which mesh with the motor output shaft gear 12 to form a gear pair, forming a gear transmission. The transmission ratio of the reduction mechanism is the output shaft gear 12 and the ball screw outer nut 17 The gear ratio of the outer face gear reduces the speed of the motor, increases the torque of the motor, and appropriately reduces the requirements of the motor. The deep groove ball bearing 16 is set on the outer side of the ball screw outer nut 17 to limit the position of the ball screw outer nut 17 and limit the movement of the ball screw outer nut 17 . Ball screw 13, ball screw outer nut 17, deep groove ball bearing 16 are all made of bearing steel.

The hydraulic source is realized by a hydraulic accumulator 6 . The solenoid valves include a hydraulic accumulator solenoid valve 7, a brake wheel cylinder solenoid valve 8 and a locking piston cavity solenoid valve 25, wherein the hydraulic accumulator solenoid valve 7 is a normally closed valve. Brake wheel cylinders 23 include four, respectively corresponding to four wheels. The above-mentioned solenoid valves can all be realized by existing mature products.

The liquid outlet of the hydraulic accumulator 6 is connected to the front chamber of the brake master cylinder 3, the rear chamber of the brake master cylinder 3, the input end of the brake wheel cylinder solenoid valve 8, and the electromagnetic valve of the lock piston chamber through the solenoid valve 7 of the hydraulic accumulator. The input end of valve 25 is connected. The output end of the brake wheel cylinder electromagnetic valve 8 is connected with the input end of the brake wheel cylinder 23 . The output end of the solenoid valve 25 of the locking piston cavity is connected with the locking piston cavity 15 to form a part of the hydraulic circuit of the braking system. The above connections are realized through hydraulic pipes (including hoses and hard pipes). The control terminals of the electromagnetic valves are connected to the electronic control unit, and they control the opening and closing of the electromagnetic valves under the control of the electronic control unit to provide power for the wheels to achieve braking.

By controlling the opening and closing of the electromagnetic valve 7 of the accumulator, the hydraulic accumulator 6 can be selectively connected to the hydraulic pipeline 20, and the hydraulic pipeline 20 is directly connected to the two working chambers of the brake master cylinder. The liquid enters and exits the hydraulic accumulator 6 to realize the size of the empty stroke between the outer casing 21 of the simulator and the piston push rod 14. When the brake fluid enters the hydraulic accumulator 6, the empty stroke will increase. When the brake fluid flows out in the opposite direction , the idle stroke will become smaller, and the same hydraulic accumulator 6 also has the function of compensating the leakage loss of the brake fluid and controlling the brake wheel cylinder solenoid valve 8 to adjust the braking clearance of the wheel brake. The pressure sensor 22 is installed on the hydraulic pipeline 20 connected to the front cavity of the piston of the brake master cylinder, and is used to detect the hydraulic pressure of the piston front cavity of the brake master cylinder. Its output end is connected with the electronic control unit, and the collected signal is sent to electronic control unit.

In terms of specific control implementation, the pressure sensor 22 obtains the pressure of the brake master cylinder 3 and the hydraulic pipeline, and calculates the displacement of the piston through the rotation angle sensor. The pressure value of the brake wheel cylinder 23 is estimated based on the relationship between the liquid pressure and the volume of the brake wheel cylinder 23, that is, the P-V characteristic, so as to realize precise control and adjustment of the pressure.

As shown in FIG. 2 , the screw pretensioning mechanism 11 includes a pretensioning horizontal link 31 , a pretensioning spring 29 , and a pretensioning vertical link 30 . The pre-tightening vertical link 30 is rod-shaped, and its top has a cylindrical through hole as the pre-tightening horizontal link mounting hole, and its bottom is directly inserted into the screw pre-tensioning mechanism mounting hole of the ball screw 13. The pre-tightening horizontal link 31 is a stepped cylindrical shape, and its left end is provided with an annular protrusion. One end of the pre-tightening horizontal link 31 passes through the pre-tightening horizontal link mounting hole of the pre-tightening vertical link 30 and is installed on the brake. On the inner wall of the rear end of the outer casing 21. The pre-tension spring 29 is set on the outside of the pre-tension cross-link 31, and is stuck between the inner wall of the rear end of the brake housing 21 and the pre-tension cross-rod 31. There is a corresponding pre-tightening force F at the position, and the pre-tightening mechanism 11 moves linearly following the lead screw. The pre-tightening vertical connecting rod 30 and the pre-tightening horizontal connecting rod 31 are all made of No. 45 steel. Preload spring 29 is a general product and can be purchased from the market.

As shown in FIG. 3 , the lockup piston chamber 15 includes a lockup piston housing 33 , a lockup piston 34 and a damping spring 32 . The locking piston housing 33 is a closed cylinder, with a liquid outlet 35 at the lower part of its front end, through which the liquid outlet 35 is connected to the output end of the solenoid valve 25 of the locking piston chamber, so that the liquid in the chamber and the brake The circuit is connected. The left end of the locking piston 34 is a long rod, and the large end of the piston is a rubber piston, and the long rod at the left end of the locking piston 34 is threadedly installed in the long rod mounting hole at the left end of the locking piston. Damping spring 32 is installed on the right-hand side of locking piston 34, plays a guiding and damping role, and spring stiffness K is less than 5000N/m. When the solenoid valve 25 of the locking piston cavity at the liquid outlet hole 35 is closed, liquid is sealed in the locking piston cavity 15, the locking piston 34 cannot move, and the simulator housing 9 cannot move in a straight line. When the solenoid valve 25 in the locking piston cavity is opened, the locking piston 34 can push liquid into the hydraulic circuit, that is, the locking piston 34 can move linearly. The same simulator housing 9 is also movable, and the limit is released. The locking piston housing 33 is made of gray cast iron, and the locking piston 34 is made of composite materials such as copper-aluminum alloy.

The brake housing 21 is cylindrical and made of No. 45 steel, and its front section is connected with the simulator end face 20 through a dust cover 36 . In this embodiment, the dustproof cover 36 is realized by a rubber dustproof cover.

The connecting pin 18 is a tapered pin, which is made of commonly used No. 45 steel. One end of it is supported on the outer surface of the piston push rod 14, and the other end is embedded in the groove of the piston 4 in the front cavity. When the motor 2 drives the ball screw 13 to move At this time, the piston push rod 14 and the front cavity piston 4 are moved together by the coupling pin 18 . When the motor 2 is unable to work, manpower is needed to push the piston push rod 14 through the simulator housing 9. During the movement of the piston push rod 14, the coupling pin 18 breaks away from the groove of the front cavity piston 4. At this time, the piston push rod 14 The front chamber piston 4 can be pushed separately to move, and the ball screw 13 is separated from it, so as to realize the brake failure backup.

The present invention adopts the connecting pin 18, which can make the piston connect with the ball screw 13 and the piston push rod 14 through the connecting pin 18. When braking, the piston push rod 14 moves linearly with the front chamber piston 4, and when a certain force is applied to the On the piston push rod 14, the piston push rod 14 promotes the front chamber piston 4 to move, and the front chamber piston 3 breaks away from the ball screw 13. When the motor 2 fails, it can be backed up in this way.

The brake wheel cylinder 23 is made of ductile iron.

The electronic control unit is a mature product, and its control of the motor, electromagnetic valve and brake wheel cylinder can be realized by using the existing technology.

In the present invention, the output shaft of the motor 2 is meshed with the outer end gear of the ball screw nut 17. The screw nut 17 is axially positioned by the deep groove ball bearing 16, so that the screw nut rotates and the ball screw 13 moves linearly. The active master cylinder piston 3 is effectively connected with the piston push rod 14 and the ball screw 13 through the connecting pin 18, that is, the ball screw 13 pushes the master cylinder piston to make a linear reciprocating motion to generate braking pressure in the brake master cylinder 3, through the control Brake wheel cylinder solenoid valve 8 selectively opens to control the connection of brake wheel cylinder 23 with brake master cylinder 3 and hydraulic pipeline 20, so that each brake wheel can be realized by controlling the opening and closing of brake wheel cylinder 23. The formation and drop of the pressure of the cylinder 23 is realized separately, and the functions of the traditional electronic control system ABS and ESP are conveniently integrated.

The solenoid valves in this system all adopt high-speed on-off valves, which are mature products on the market. The pressure sensor 22 also follows the scheme of the traditional braking system. For the existing technology, the implementation method has been verified. The brake master cylinder 3 and the piston mechanism adopt a traditional plunger-type master cylinder design, and the specific size and requirements match with the vehicle type, and can be realized by using existing technologies. While retaining the traditional structure of the brake wheel cylinder 23, the structure of the brake wheel cylinder 23 remains unchanged, and the hydraulic pipelines are arranged in X rows, that is, arranged in diagonal lines to meet the requirements of the braking regulations. In this way, when a When the circuit breaks down, there are still two brake wheel cylinders 23 that can function, and the braking efficiency can maintain at least 50%.

The working process of this system is as follows:

When the car is running normally, when the driver steps on the brake pedal 1, the electronic control unit analyzes the driver's intention through the pedal displacement sensor 19, drives the motor 2 to rotate, and drives through the meshing transmission of the motor output shaft gear 12 and the ball screw nut 17. Make the ball screw 13 move in a straight line, the front chamber piston 4 is fixed by the ball screw 13 and the connecting pin 18, the ball screw 13 pushes the front chamber piston 4 to move in a straight line, brake pressure is generated in the brake master cylinder 3, and the brake wheel is opened Cylinder solenoid valve 8, the brake fluid enters the brake wheel cylinder 23 to generate braking torque. If pressure maintenance is required, the brake wheel cylinder electromagnetic valve 8 is closed, and the brake wheel cylinder 23 is pressure maintained. If decompression is required, the motor 2 reverses, the piston 4 in the front chamber of the master cylinder moves in the opposite direction, and the brake wheel cylinder solenoid valve 8 that also controls the brake wheel cylinder 23 is opened, and the brake fluid flows back from the brake wheel cylinder 23 to the main cylinder. In the front chamber of the cylinder.

When braking requires that there is a difference in the pressure of each brake wheel cylinder 23, the electronic control unit sends control information to the corresponding brake wheel cylinder solenoid valve 8, which can be opened separately, such as the brake wheel cylinder solenoid valve 8 that controls the left front wheel, and closed. The other three brake wheel cylinder solenoid valves 8 control the brake pressure of the left front wheel. After this process is over, close the brake wheel cylinder electromagnetic valve 8 of the left front wheel, and adjust the pressure of one of the remaining 3 brake wheel cylinders 23, so that the pressure of the 4 brake wheel cylinders 23 is at a certain level. The desired braking pressure is achieved within the control period, and the sequential braking method is adopted in the control according to the priority.

When the power source motor 2 breaks down, the solenoid valve 25 of the locking piston chamber is opened. Under normal circumstances, the solenoid valve 25 of the locking piston chamber is closed, that is, the simulator housing 9 is fixed in the axial direction, so that people can step on it There is no looseness when braking the pedal. The solenoid valve 25 of the locking piston cavity is opened, and the locking piston cavity 15 communicates with the brake master cylinder 3 through the hydraulic pipeline. At this time, when the person depresses the brake pedal 1 again, the pedal stroke simulator 9 will move axially. After overcoming the idle stroke with the piston push rod 14, the master cylinder piston will be pushed together with the piston push rod 14 to generate brake pressure, that is, the system has a brake backup structure.

In the anti-lock braking stage, on the basis of conventional braking, if the right front wheel enters a slipping state, the electronic control unit decompresses the right brake wheel cylinder 23, that is, the right brake wheel cylinder 23 and the brake master The brake master cylinder solenoid valve 8 between the cylinders is opened, the motor 2 reverses and drives the front chamber piston 4 to move in the reverse direction, and the pressure of the brake master cylinder 3 drops. At this time, the pressure of the right front brake wheel cylinder 23 is greater than the internal pressure of the brake master cylinder 3 hydraulic pressure, the right front wheel is decompressed, while the solenoid valve 8 of the other three-way brake wheel cylinder is closed, and it is in a pressure maintaining state. If there are multiple wheels entering the slipping state, the electronic control unit will control each The pressure of the brake wheel cylinder 23 is controlled sequentially, and the pressure adjustment of a certain wheel brake wheel cylinder 23 can also be completed in several adjustment cycles, and its principle is consistent with the principle of single wheel increase, decrease, and pressure maintenance.

When the vehicle is unstable, the electronic control unit calculates the pressure that needs to be adjusted for each target wheel brake wheel cylinder 23 by analyzing the pressure of each sensor and brake wheel cylinder, combined with the state information of the vehicle, and then increases the pressure of the wheel cylinder through the solenoid valve. , reducing, and pressure-holding process, its principle is the same as the wheel anti-lock situation during braking, so that the brake wheel cylinder 23 pressure reaches the expected value.

In the active braking phase, the electronic control unit distributes the pressure of each brake wheel cylinder 23 through the electromagnetic valve through the signal collected by the sensor. This system can also actively pressurize each brake wheel cylinder 23. The process is as described above. .

The invention cancels the vacuum booster, cancels the mechanical connection between the brake pedal and the hydraulic chamber, effectively reduces the overall quality, has a compact structure and is easy to arrange. The structural complexity is greatly reduced, and the cost is reduced. By using the motor as the power source, that is, using mechanical and electrical connections, the signal transmission is fast and the braking response is fast. Differential braking is achieved by controlling solenoid valves and motors. The brake backup of the mechanical structure is very different from the general brake-by-wire system. When the electrical structure fails, the backup structure can quickly intervene to produce a certain braking effect, ensuring driving safety and meeting the requirements of braking regulations. .

In the present invention, the outer surface of the lead screw nut is processed into a gear, which meshes with the output shaft gear of the motor to form a ball screw pair. On the basis of not adding other accessories, the torque requirement for the motor is reduced, and the torque of the motor is also reduced. The size makes the structure of the whole braking system simple. By using the hydraulic accumulator to compensate the hydraulic leakage of the braking system, the relative clearance of the push rod brake piston can be adjusted steplessly, which is simpler in structure and lower in cost than using a hydraulic liquid storage chamber.

Claims (7)

1. a kind of have the Multifunctional brake system for slowing down and increasing and turning round movement conversion mechanism and active regulation, including brake shell body (21), motor (2), brake pedal simulator, master cylinder (3), movement conversion mechanism, hydraulic power source, magnetic valve and wheel cylinder (23)；Brake pedal simulator is connected with brake shell body (21) leading portion, and brake pedal simulator is felt for simulating brake With the braking intention for obtaining driver, it is used to realize wheel braking when motor (2) fails；Brake shell body (21) is cylinder Shape, the back segment of brake shell body (21) are connected with movement conversion mechanism；Motor (2) be arranged on master cylinder (3) on, respectively with Electronic control unit connects with movement conversion mechanism, rotates under the control of electronic control unit, is provided for movement conversion mechanism Power；Movement conversion mechanism is also connected with master cylinder (3), and the rotation of motor (2) is changed into linear motion, drives braking master Cylinder (3) realizes wheel braking；Master cylinder (3) provides hydraulic pressure under the drive of movement conversion mechanism for automobile brake；Hydraulic power source It is connected with magnetic valve, for compensating hydraulic pressure leakage；Wheel cylinder (23) is connected by magnetic valve with master cylinder (3), in electricity Under the control of sub-control unit, realize that braking provides power for wheel；Described pedal simulator includes brake pedal (1), stepped on Plate push rod (26), simulator end face (20), simulator main pin (28), simulator shell body (9), sleeve (27), damping element (10), pedal displacement sensor (19) and pedal simulator damping spring (24)；Before brake pedal (1) and pedal push rod (26) End is bolted, and lower drive pedal push rod (26) motion is trampled in driver；Simulator end face (20) is discoid, in Through hole is provided with the heart, is fixedly connected with the front end of sleeve (27)；Sleeve (27) is cylindrical shape, and front end surface is provided with bellmouth, in Snap ring is provided with the outside of portion, the front end of snap ring is withstood in the front inner wall of simulator housing (9), and blind hole work is provided with the middle part of back segment For simulator main pin (28) mounting hole；The rear end of pedal push rod (26) passes through the through hole and sleeve in the middle part of simulator end face (20) (27) front end connection；Simulator housing (9) is the cylindrical shape of both ends open, the size of rear and front end opening respectively with sleeve (27) external diameter and the external diameter of simulator main pin (28) rear end is consistent, and the rear end of simulator housing is provided with screwed hole as lock Only piston left end stock mounting hole；Simulator main pin (28) is cylinder, and front portion is arranged in the through hole in the middle part of sleeve (27), Rear end external diameter is arranged on simulator housing (9) rear end compared with simulator main pin (28) small 3~5mm of main part external diameter, rear end In opening, circular groove is provided with the center of rear end end face as damping element mounting hole；Pedal simulator damping spring (24) It is sleeved on sleeve (27) and simulator main pin (28) outside, front end is withstood on the rear end end face of sleeve (27) snap ring, and rear end is withstood on On the inwall of simulator housing (9) rear end, reaction force is provided for operator brake to simulate the brake feel of traditional vehicle；Pedal position Displacement sensor (19) is connected by support with the lever of brake pedal (1), and is fixedly mounted on simulator housing (9) bottom end face On, pedal displacement sensor (19) collection pedal displacement signal, and send the signal to electronic control unit；Damping element (10) it is relative with piston push rod (14) installation site in the damping element mounting hole of simulator main pin (28) rear end Should；Described hydraulic power source realizes that the liquid outlet of hydraulic accumulator (6) passes through hydraulic accumulator electromagnetism using hydraulic accumulator (6) Valve (7) and master cylinder (3) ante-chamber, master cylinder (3) back cavity, the input of wheel cylinder magnetic valve (8), lockup piston chamber electricity The input connection of magnet valve (25)；The output end of wheel cylinder magnetic valve (8) is connected with the input of wheel cylinder (23)；Locking The output end of plunger shaft magnetic valve (25) is connected with lockup piston chamber (15)；Described lockup piston chamber (15) includes lockup piston Housing (33), lockup piston (34), damping spring (32)；Lockup piston housing (33) is the cylindrical shape of closing, and front lower portion is opened There is plunger shaft fluid hole (35), be connected, made with the output end of lockup piston chamber magnetic valve (25) by plunger shaft fluid hole (35) Intracavity liquid is obtained with brake circuit to be connected；Lockup piston (34) left end is stock, and the big end of piston is rubber piston, lockup piston Left end stock is by being threadably mounted in lockup piston left end stock mounting hole；Damping spring (32) is arranged on lockup piston (34) Right-hand member, plays guiding and damping action, spring rate K are less than 5000N/m.

2. system according to claim 1, it is characterised in that：Described pedal simulator integral installation is in braking shell body (21) leading portion, and with piston push rod (14) keep 20~30mm gap.

3. system according to claim 1, it is characterised in that：Described motor (2) using brushless direct current motor realize, The stall moment of torsion of motor (2) is 4Nm, and idler revolutions can reach 2000rpm in 4ms, and the unitary rotation inertia of motor is 10-5 numbers Magnitude.

4. system according to claim 1, it is characterised in that：Described master cylinder (3) uses plunger typed master cylinder structure, Brake master cylinder piston is arranged in master cylinder (3), and brake master cylinder piston includes ante-chamber piston (4) and back cavity piston (5)；Ante-chamber Master cylinder (3) is divided into two independent hydraulic cavities by piston (4) and back cavity piston (5)；The front end top of back cavity piston spring On the inwall of back cavity piston (5) closing one end, rear end is withstood on the inwall of master cylinder (3) closing one end；Ante-chamber piston (4) Groove is provided with the middle part of one end outer face of closing to push away installed in piston as piston push rod mounting hole, the rear end of piston push rod (14) In bar mounting hole；It is connected outside one end outer face of ante-chamber piston (4) closing with movement conversion mechanism；Ante-chamber piston spring front end Withstand on the inwall of ante-chamber piston (4) closing one end, the rear end of ante-chamber piston spring withstands on the end of back cavity piston (5) closing one end On face.

5. system according to claim 1, it is characterised in that：Described movement conversion mechanism includes motor output shaft gear And ball screw pair (12)；Wherein, motor output shaft gear (12) is little gear；Ball screw is secondary include ball-screw (13), Ball and ball-screw outer nut (17)；Ball-screw (13) is hollow structure, and it is pre- as leading screw to be provided with groove on its top The mounting hole of tight mechanism (11), is sleeved on the outside of piston push rod (14), and rear end withstands on the outer wall of ante-chamber piston (4) closing one end On；Ball-screw outer nut (17) is beloid boss structure, outer wall is gear structure, is sleeved on ball-screw (13) outside Side, ball is clipped between the two, rear end end face withstands on the end face and ante-chamber piston (4) closing of master cylinder (3) open at one end On the end face of one end, engaged with motor output shaft gear (12) and form gear pair.

6. system according to claim 5, it is characterised in that：It also includes deep groove ball bearing (16), deep groove ball bearing (16) it is sleeved on the outside of ball-screw outer nut (17), ball-screw outer nut (17) is carried out spacing.

7. system according to claim 5, it is characterised in that：Described leading screw pre-tightening mechanism (11) includes pretension tranverse connecting rod (31), preloading spring (29), pretension vertical connecting rod (30)；Pretension vertical connecting rod (30) is shaft-like, and top is provided with cylindrical hole conduct Pretension tranverse connecting rod mounting hole, bottom straight cutting enter in the leading screw pre-tightening mechanism mounting hole of ball-screw (13)；Pretension tranverse connecting rod (31) For stepped cylinder shape, left end is provided with annular projection, and one end of pretension tranverse connecting rod (31) passes through the pretension of pretension vertical connecting rod (30) Tranverse connecting rod mounting hole, on the inwall of brake shell body (21) rear end；Preloading spring (29) is sleeved on pretension tranverse connecting rod (31) outside, is stuck between brake shell body (21) rear end inwall and pretension tranverse connecting rod (31), and preloading spring (29) is in pressure Contracting state.