CN214775823U

CN214775823U - Brake pedal assembly for electric vehicle

Info

Publication number: CN214775823U
Application number: CN202121255431.4U
Authority: CN
Inventors: 龚小祥; 卢志航; 肖飞; 公冶祥玉; 高峰; 葛卫国; 王利锋
Original assignee: Chongqing Three Gorges University
Current assignee: Chongqing Three Gorges University
Priority date: 2021-06-03
Filing date: 2021-06-03
Publication date: 2021-11-19
Anticipated expiration: 2031-06-03

Abstract

The utility model discloses a brake pedal assembly for electric vehicle, which comprises a pedal bracket and a brake pedal hinged on the pedal bracket, and is characterized by also comprising a linear motor for generating analog feedback force, wherein one end of the linear motor is hinged on the pedal bracket, and the other end is hinged in the middle of the brake pedal; and a stroke detection mechanism for detecting the treading stroke of the pedal and a return spring for resetting the brake pedal are also arranged between the pedal bracket and the brake pedal, and the linear motor and the stroke detection mechanism are both connected to the brake controller. The utility model has the advantages of structural design is simple, and simple to operate can provide brake pedal feedback force, is favorable to improving driving experience.

Description

Brake pedal assembly for electric vehicle

Technical Field

The utility model relates to an electric automobile braking technical field, very much relate to a brake pedal assembly for electric automobile.

Background

As the technology of electric vehicles matures, more and more automobile manufacturers are beginning to research and develop electric vehicles. Electric vehicles are motor driven and do not have an internal combustion engine, whereas conventional hydraulic braking systems rely on vacuum provided by the internal combustion engine as a source of assistance. Although the hydraulic brake system is still used in the current electric vehicle, a separate hydraulic device must be added, so that the cost of the brake system is increased and a lot of space is occupied.

With the further maturity and popularization of electric automobile technology, the drive-by-wire technology will be gradually applied to electric automobiles, including a steer-by-wire system, a throttle-by-wire system and a brake-by-wire system. The brake pedal of the brake-by-wire system is not directly connected with the wheel brake mechanism hydraulically or mechanically, and is a decoupled working mode.

When a driver steps on the brake pedal, the brake pedal is decoupled from the brake mechanism, the brake pedal transmits a brake instruction to an electric control system of the wheel brake mechanism through an electric signal, the electric control system performs brake control according to the received electric signal, but the reverse action of the wheel brake mechanism cannot be reversely transmitted to the brake pedal, the feedback feeling of the brake pedal of the traditional brake system is lacked, and the driver cannot feel the road surface or the vehicle body through the brake pedal.

SUMMERY OF THE UTILITY MODEL

To the not enough of above-mentioned prior art, the utility model aims to solve the technical problem that: how to provide a simple structure, simple to operate can provide brake pedal feedback force, is favorable to improving the brake pedal assembly for electric motor car that drives and experience.

In order to solve the technical problem, the utility model discloses a following technical scheme:

a brake pedal assembly for an electric vehicle comprises a pedal bracket and a brake pedal hinged on the pedal bracket, and is characterized by also comprising a linear motor for generating analog feedback force, wherein one end of the linear motor is hinged on the pedal bracket, and the other end of the linear motor is hinged in the middle of the brake pedal; and a stroke detection mechanism for detecting the treading stroke of the pedal and a return spring for resetting the brake pedal are also arranged between the pedal bracket and the brake pedal, and the linear motor and the stroke detection mechanism are both connected to the brake controller.

On the basis of the hardware configuration, during braking, a driver treads a brake pedal, a stroke detection mechanism acquires a detection signal of a pedal treading stroke and then sends the detection signal into a brake controller, the brake controller can calculate braking force acting on each wheel according to the signal, and meanwhile, the linear motor can be controlled according to the signal to generate axial thrust, pedal feedback force is simulated, brake feedback is given to the driver, and driving experience is improved. After the driver releases the brake pedal, the brake pedal is restored to the original position under the action of the return spring. The linear motor has simple structure, convenient and reliable control of axial thrust, and is beneficial to simplifying the structure of the brake pedal and convenient to install.

Further, the linear motor comprises a cylindrical shell and a push rod which is arranged in the shell in an axially telescopic mode, the outer end portion of the push rod is hinged to the brake pedal, the reset spring is a spiral spring which is sleeved on the push rod, and two ends of the reset spring are connected to the shell and the brake pedal respectively.

Thus, when the brake pedal is treaded, the push rod is pushed to contract towards the inside of the shell, and meanwhile, the return spring between the shell and the brake pedal is compressed. During installation, the reset spring is only required to be sleeved outside the push rod, one end of the reset spring is abutted to the end of the shell, meanwhile, the push rod is pulled out and hinged to the brake pedal, the other end of the reset spring is abutted to the hinged position of the push rod and the brake pedal, assembly can be completed, and operation is simple and convenient.

Furthermore, one end of the push rod, which is far away from the shell, is provided with a vertically arranged positioning plate, and two ends of the return spring are respectively abutted against the shell and the positioning plate.

Like this, through locating plate with reset spring integrative the installing on linear electric motor, during the use, only need install linear electric motor and just can accomplish the assembly between pedal support and brake pedal, simplified mounting structure more.

Further, the return spring is a conical spiral spring.

The conical spiral spring has good buffering performance and can bear large load.

Furthermore, the shell is internally and fixedly provided with an annular permanent magnet, the inward end of the push rod is connected with a motor coil, and the motor coil is electrically connected to the brake controller.

Therefore, when a driver treads the brake pedal, the push rod can push the motor coil to move axially in the shell, the coil moving in the magnetic field of the permanent magnet can generate induced electromotive force, and the electromotive force is in direct proportion to the movement speed of the motor coil, namely the pedaling speed of the brake pedal. The stepping speed of the brake pedal can be obtained by detecting the magnitude of the induced electromotive force. Meanwhile, the treading stroke of the brake pedal can be obtained, and the brake controller can calculate the braking force acting on each wheel according to the signal, so that the redundancy performance of the system is improved.

Further, the push rod is made of stainless steel, and the stroke detection mechanism is a displacement sensor sleeved on the push rod and mounted at the end of the shell.

Therefore, the stroke detection mechanism can be integrated on the linear motor together by adopting the displacement sensor sleeved on the push rod, and the installation structure is further simplified.

Further, the permanent magnet includes that an organic whole is annular first permanent magnet and is curved second permanent magnet, and is a plurality of the second permanent magnet meets along the circumferencial direction and is annular magnetism group, first permanent magnet and annular magnetism group are provided with a plurality ofly along the axial at interval in proper order.

Further, the first permanent magnet and the second permanent magnet are arranged in a Halbach array.

Furthermore, the permanent magnet is made of a neodymium iron boron strong magnetic material.

Further, the motor coils are axially provided with two groups.

Compare with present widely used hydraulic brake pedal simulator, the utility model has the advantages of as follows:

1. original components such as a hydraulic pump, a hydraulic pipeline, a piston and a hydraulic cylinder are not needed, and the system structure is simpler.

2. The electric vehicle battery directly provides electric energy, and the electric energy does not need to be converted into hydraulic pressure firstly, and the hydraulic pressure is converted into the energy conversion process of piston motion.

3. Electromechanical systems respond more quickly than hydraulic systems and can provide a more rapid braking response.

Drawings

Fig. 1 is a schematic view of the overall structure of the brake pedal assembly of the present invention.

Fig. 2 is a schematic view of the magnetic field of the halbach permanent magnet array.

Fig. 3 is a schematic structural diagram of the first permanent magnet.

FIG. 4 is a schematic structural diagram of a ring magnet assembly.

Fig. 5 is a schematic structural diagram of a motor coil.

Fig. 6 is a sectional view of the linear motor.

Fig. 7 is a schematic structural view of an initial state of the pedal simulator.

Fig. 8 is a structural diagram illustrating a braking state of the pedal simulator.

Fig. 9 and 10 are schematic diagrams of different positions of the motor coils within the magnetic field.

Detailed Description

The present invention will be described in further detail with reference to examples.

In the specific implementation: as shown in fig. 1 to 10, a brake pedal assembly for an electric vehicle includes a pedal bracket 1, a brake pedal 2 hinged to the pedal bracket 1, and a linear motor 3 for generating an analog feedback force, wherein one end of the linear motor 3 is hinged to the pedal bracket 1, and the other end is hinged to the middle of the brake pedal 2; and a stroke detection mechanism 4 for detecting the treading stroke of the pedal and a return spring 5 for returning the brake pedal are also arranged between the pedal bracket 1 and the brake pedal 2, and the linear motor 3 and the stroke detection mechanism 4 are both connected to the brake controller.

In implementation, the linear motor 3 includes a cylindrical housing 31 and a push rod 32 axially and telescopically disposed in the housing 31, an outer end portion of the push rod 32 is hinged to the brake pedal 1, the return spring 5 is a coil spring sleeved on the push rod 32, and two ends of the coil spring are respectively connected to the housing 31 and the brake pedal 2.

In implementation, one end of the push rod 32, which is away from the housing 31, is provided with a positioning plate 33 which is vertically arranged, and two ends of the return spring 5 are respectively abutted against the housing 31 and the positioning plate 33.

In practice, the return spring 5 is a conical coil spring.

In implementation, the housing 31 is internally and fixedly provided with an annular permanent magnet 34, the inward end of the push rod 32 is connected with a motor coil 35, and the motor coil 35 is electrically connected to the brake controller.

During implementation, the push rod 32 is made of stainless steel, the stroke detection mechanism 4 is a displacement sensor sleeved on the push rod 32 and mounted at the end of the shell 31, and in this embodiment, the displacement sensor is a differential transformer type displacement sensor.

In practice, two sets of the motor coils 35 are arranged along the axial direction. The permanent magnet 34 is made of a neodymium iron boron strong magnetic material. Be annular first permanent magnet and be curved second permanent magnet including an organic whole, it is a plurality of the second permanent magnet meets along the circumferencial direction and is annular magnetic unit, first permanent magnet and annular magnetic unit are provided with a plurality ofly along the axial in proper order at interval. The first permanent magnet and the second permanent magnet are arranged in a Halbach array.

When the brake is not applied, the relative positions of the brake pedal, the push rod, the return spring and the linear motor are shown in fig. 7, and the distance between the lower end of the push rod and the bottom of the linear motor is S0 at this time, as shown in fig. 7. When braking is needed, a driver steps on the brake pedal 2, the brake pedal rotates around the support fixed pivot, the return spring is compressed, the push rod 32 and the stroke detection mechanism 4 are driven to move relatively, and the push rod 32 pushes the motor coil 35 to move downwards, as shown in fig. 8. At this time, the distance between the lower end of the push rod and the bottom of the linear motor is S1, and then the relative displacement of the push rod is:

S＝S0-S1

the stroke detection mechanism 4 can detect this displacement signal, thereby acquiring the brake pedal effort of the driver. The greater the force by which the driver steps on the brake pedal, the greater the amount of compression of the return spring 5, and the greater the relative displacement S between the push rod 32 and the stroke detection mechanism 4. Further, the more rapidly the driver steps on the brake pedal, the more induced electromotive force is generated by the motor coil, which can be measured with a voltage sensor. The displacement of the brake pedal and the electromotive force induced by the coil are collected by the sensor and transmitted to the brake controller, and the brake controller calculates the braking force acting on each wheel according to the displacement and speed signals of the brake pedal. Under the condition of braking, the coil is not actively electrified, namely the linear motor does not provide thrust, and after braking is finished, the return spring 5 provides the restoring force of the brake pedal.

When the ABS system is started due to emergency braking or the road surface is bumpy, the brake pedal simulator needs to provide braking feedback force for a driver, namely, the linear motor provides thrust force for the brake pedal in a reverse direction, so that the driver obtains a 'foot-supporting' braking feedback feeling. When the linear motor provides thrust, if the required feedback force is small, current can be intermittently introduced into the two groups of coil windings according to the situation, and the thrust directions of the linear motor are the same by adjusting the current directions of the coils. If the required feedback force is large, the two sets of coil windings can be simultaneously electrified, and the direction of the current is different according to the position of the coil, as shown in fig. 9 and 10. When the two coil windings are positioned on different arc-shaped permanent magnets, the current directions of the two coils are opposite; when the two coil windings are located on the same arc-shaped permanent magnet, the current directions of the two coils are the same. In this way, the directions of the electromagnetic forces applied to the two coil windings are the same, the electromagnetic forces are mutually superposed, and finally, the doubled thrust is provided, and the strength and the frequency of the thrust are consistent with those of an ABS system.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the present invention, and any modifications, equivalents and improvements made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.

Claims

1. A brake pedal assembly for an electric vehicle comprises a pedal bracket (1) and a brake pedal (2) hinged on the pedal bracket (1), and is characterized by further comprising a linear motor (3) for generating analog feedback force, wherein one end of the linear motor (3) is hinged on the pedal bracket (1), and the other end of the linear motor is hinged in the middle of the brake pedal (2); and a stroke detection mechanism (4) for detecting the treading stroke of the pedal and a return spring (5) for resetting the brake pedal are also arranged between the pedal bracket (1) and the brake pedal (2), and the linear motor (3) and the stroke detection mechanism (4) are both connected to the brake controller.

2. The brake pedal assembly for the electric vehicle according to claim 1, wherein the linear motor (3) comprises a cylindrical housing (31) and a push rod (32) axially telescopically arranged in the housing (31), the outer end of the push rod (32) is hinged to the brake pedal (2), the return spring (5) is a coil spring sleeved on the push rod (32), and two ends of the coil spring are respectively connected to the housing (31) and the brake pedal (2).

3. The brake pedal assembly for the electric vehicle as claimed in claim 2, wherein one end of the push rod (32) facing away from the housing (31) is provided with a vertically arranged positioning plate (33), and two ends of the return spring (5) abut against the housing (31) and the positioning plate (33), respectively.

4. The brake pedal assembly for electric vehicles according to claim 2 or 3, wherein the return spring (5) is a conical coil spring.

5. The brake pedal assembly of claim 2, wherein the housing (31) is fixedly provided with a ring-shaped permanent magnet (34), the inward end of the push rod (32) is connected with a motor coil (35), and the motor coil (35) is electrically connected to the brake controller.

6. The brake pedal assembly for the electric vehicle according to claim 5, wherein the push rod (32) is made of stainless steel, and the stroke detection mechanism (4) is a displacement sensor fitted over the push rod (32) and mounted at an end of the housing (31).

7. The brake pedal assembly for the electric vehicle as defined in claim 5, wherein the permanent magnet (34) includes a first permanent magnet and a second permanent magnet, the first permanent magnet and the second permanent magnet being formed in an arc shape and integrally formed in a ring shape, the second permanent magnets are connected in a circumferential direction to form a ring-shaped magnet assembly, and the first permanent magnet and the ring-shaped magnet assembly are sequentially arranged in a plurality at intervals in an axial direction.

8. The brake pedal assembly for an electric vehicle of claim 7, wherein the first and second permanent magnets are arranged in a halbach array.

9. The brake pedal assembly for electric vehicles according to claim 7 or 8, wherein the permanent magnet (34) is made of a strong magnetic material of neodymium iron boron.

10. The brake pedal assembly for electric vehicles according to claim 9, wherein the motor coils (35) are arranged in two sets in the axial direction.