Dot-matrix brake mechanism

Abstract

The invention discloses a dot-matrix brake mechanism which comprises a brake disc and a brake caliper body, one end of the brake disc is arranged in the brake caliper body, the dot-matrix brake mechanism further comprises friction plates, every two friction plates form a group of brake units, and the two friction plates of each group of brake units are symmetrically arranged on the two sides of the brake disc. All the friction plates on each side of the brake disc are arranged on the brake caliper body in an array mode. And each group of brake unit is independently controlled to realize the brake action. Compared with an existing mainstream brake system, the brake system has the advantages that the brake power and size of a single brake execution mechanism are small, the effective action area of the friction plates is large, gaps exist between the friction plates, and heat dissipation is good.

Description

Technical Field

[0001] The invention relates to a dot matrix braking mechanism. Background Art

[0002] Electronic hydraulic brake system (EHB) and electronic mechanical brake system (EMB) are the current research hotspots and development trends of passenger car brake systems.

[0003] The EMB system adopts a distributed layout, with the motor directly applying braking torque to each wheel. It has the advantages of not requiring brake fluid and complex brake fluid pipelines. However, it generally adopts a structural mode of one or two motors, and has problems such as low braking reliability and fault tolerance. The actual installation rate is still relatively low.

[0004] The EHB system is developed based on the traditional hydraulic braking system. It has made electronic control improvements to the traditional hydraulic braking system and has better braking performance and braking reliability. With the continuous improvement of the requirements for the response speed, control accuracy and fault tolerance of the automobile braking system due to unmanned driving and automatic driving, the EHB system needs to be upgraded and redesigned.

[0005] In order to explore the advantages of EMB and EHB systems and meet the new requirements of autonomous driving and unmanned driving on the braking system, a dot matrix multi-actuator can be used to individually control the friction plate, and different combination modes can be selected to achieve braking. If one or even multiple brake actuators fail, the other brake actuators can still complete the vehicle braking function, thereby improving the fault tolerance and working reliability of the braking system. To this end, the present application proposes a dot matrix braking mechanism. Summary of the invention

[0006] The present invention provides a dot matrix brake mechanism in order to solve the problems existing in the prior art.

[0007] The technical solutions adopted in the present invention are: A dot matrix brake mechanism comprises a brake disc and a brake caliper body, wherein one end of the brake disc is placed in the brake caliper body, and the brake mechanism also comprises a friction plate, wherein two friction plates form a group of brake units, and the two friction plates of each group of brake units are symmetrically arranged on both sides of the brake disc, and all friction plates on each side of the brake disc are arranged in an array on the brake caliper body; each group of brake units is independently controlled to realize braking action.

[0008] Furthermore, the friction plates of each brake unit are controlled by a mechanical actuator to achieve braking action.

[0009] Furthermore, the mechanical actuator includes a motor and an actuator screw, each friction plate is driven by a motor-linked actuator screw, and the two friction plates of each brake unit maintain synchronous movement.

[0010] Furthermore, a brake pressure sensor is provided on the end surface of the friction plate away from the brake disc.

[0011] Furthermore, the friction plates of each brake unit are controlled by a hydraulic actuator to achieve braking action.

[0012] Furthermore, the hydraulic actuator includes a hydraulic control unit and a double-piston brake wheel cylinder. The two friction plates in each brake unit are fixed to the two pistons in the double-piston brake wheel cylinder. The hydraulic control unit is provided with several branches, and each branch controls a double-piston brake wheel cylinder separately.

[0013] Furthermore, the hydraulic control unit includes a fluid reservoir, a hydraulic pump and a hydraulic accumulator. The fluid reservoir is used to store brake fluid, the hydraulic pump is used to transfer brake fluid to the hydraulic accumulator, the hydraulic accumulator is connected to a plurality of branches, each branch is connected to a double-piston brake wheel cylinder, each double-piston brake wheel cylinder is connected to a brake fluid circuit, and all brake fluid circuits are connected to the fluid reservoir.

[0014] Furthermore, each branch line is provided with a liquid inlet solenoid valve, and each brake fluid circuit is connected with a liquid outlet solenoid valve.

[0015] Furthermore, a hydraulic pressure sensor is provided on the hydraulic accumulator, and a hydraulic pressure sensor is provided in the double-piston brake wheel cylinder.

[0016] The present invention has the following beneficial effects: (1) Compared with the current mainstream braking system, the present invention has the advantages of small braking power and size of a single brake actuator, large effective area of ​​friction plates, and good heat dissipation due to gaps between friction plates.

[0017] (2) In the present invention, during emergency braking, all brake actuators on both sides of the brake disc work simultaneously, which can shorten the response time of vehicle braking and improve the braking efficiency of the vehicle.

[0018] (3) The present invention arranges a plurality of brake actuators on both sides of the brake disc. Each group of brake actuators can select different working combination modes according to the required braking torque and the value of the cumulative braking load borne by each group of brake actuators.

[0019] (4) The present invention arranges a plurality of brake actuators on both sides of the brake disc. The brake torque provided by each group of brake actuators is relatively small. When the anti-lock braking system is working and the brake pressure is adjusted, the accuracy and performance of the anti-lock braking control and the brake torque control can be improved.

[0020] (5) The present invention arranges a plurality of brake actuators on both sides of the brake disc. If one or more brake actuators fail, the other brake actuators can still complete the braking function of the vehicle, thereby improving the fault tolerance and working reliability of the brake system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a structural diagram of the present invention.

[0022] Figure 2 Layout diagram for each independently working friction plate.

[0023] Figure 3 and Figure 4 This is a schematic diagram of using a mechanical actuator to control the braking action.

[0024] Figure 5 and Figure 6 This is a schematic diagram of using a hydraulic actuator to control the braking action.

[0025] Figure 7 This is a schematic diagram of multiple friction plates arranged in parallel in one layer. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings.

[0027] like Figure 1 and Figure 2 The present invention discloses a dot matrix brake mechanism, comprising a brake disc 1, a brake caliper body 2 and a friction pad 3. One end of the brake disc 1 is placed in the brake caliper body 2. A plurality of friction pads 3 form a group of brake units in pairs. The two friction pads 3 of each group of brake units are symmetrically arranged on both sides of the brake disc 1. All friction pads 3 on each side of the brake disc 1 are arranged in an array on the brake caliper body 2. Each group of brake units is independently controlled to realize braking action.

[0028] like Figure 3 The friction plates 3 of each brake unit are controlled by a mechanical actuator to achieve braking action. The mechanical actuator includes a motor 41 and an actuator screw 42. Each friction plate 3 is driven by a motor 41 and an actuator screw 42. The two friction plates 3 of each brake unit are kept in synchronous motion by the linkage of two motors and two actuator screws.

[0029] A brake pressure sensor is provided on the end surface of the friction plate 3 away from the brake disc 1 for real-time feedback of the brake pressure on both sides of the brake disc 1 .

[0030] The plurality of friction plates 4 are arranged in two layers (eg Figure 1 and 2 ), or they can be arranged in parallel in one layer (such as Figure 7), there are gaps between the friction plates 4, which have good heat dissipation performance.

[0031] When in use, the single braking load can be calculated based on the braking pressure and braking time of a single motor, and then the cumulative braking load of each motor can be calculated. The motors on each side of the brake disc 1 select different motor working combination modes according to the required braking torque and the cumulative braking load borne by each motor, so that each motor actuator works in a balanced manner.

[0032] like Figure 4 Taking 10 motors as an example, there are 5 motors on each side of the brake disc 1. The motors on one side are numbered M1-M5, and the motors on the other side are numbered M6-M10, where M1 and M6 are a group, M2 and M7 are a group, and so on.

[0033] When the accumulated braking loads of the 10 motors are basically the same, different motor working combination modes are adopted according to the required braking torque. For example, according to the required braking torque, the threshold values ​​a1, a2, a3, a4, and a5 can be set from small to large. When the required braking torque is less than a1, the braking torque is provided by the M2 motor and its symmetrical motors; when the required braking torque is between a1 and a2, the braking torque is provided by the M4 motor, M5 motor and their symmetrical motors; when the required braking torque is between a2 and a3, the braking torque is provided by the M1 motor, M3 motor and their symmetrical motors; when the required braking torque is between a3 and a4, the braking torque is provided by the M2 motor, M4 motor, M5 motor and their symmetrical motors; when the required braking torque is between a4 and a5, the braking torque is provided by the M1 motor, M3 motor, M4 motor, M5 motor and their symmetrical motors; when the required braking torque is higher than a5, the braking torque is provided by the M1 motor, M2 motor, M3 motor, M4 motor, M5 motor and their symmetrical motors, that is, all 10 motors participate in the braking work.

[0034] At the same time, when different combination modes change, a reasonable braking mode switching strategy is designed to make the braking mode switching smooth and reliable. This different working combination mode can make each motor actuator work in a balanced manner and improve the heat dissipation performance and thermal degradation resistance of the braking actuator.

[0035] When the accumulated braking loads of the ten motors are inconsistent, during the braking process, the motor with the smaller accumulated braking load is preferentially used to apply the braking torque, so that the accumulated braking loads of the ten motors tend to be consistent.

[0036] When the vehicle is in emergency braking condition, all 10 motors on both sides of the brake disc 1 will start working quickly at the same time, which can shorten the response time of the vehicle's braking and improve the braking efficiency and safety performance of the vehicle.

[0037] When the anti-lock braking system is working, it is necessary to quickly increase, decrease, and maintain the braking torque of the wheel. At this time, one or two groups of motors can participate in the braking torque adjustment work. Since the braking pressure provided by each motor is relatively small, the braking torque adjustment response is fast. During the operation of the anti-lock braking system and the braking pressure adjustment process, the accuracy and performance of the anti-lock braking control and braking torque control can be improved.

[0038] There are 10 motors arranged on both sides of the brake disc 1. If one or even more motors fail, the other motors can still complete the vehicle braking function, thereby improving the fault tolerance and working reliability of the vehicle braking system, meeting the requirements of unmanned and automatic driving vehicles.

[0039] like Figure 5 and Figure 6 In the present invention, the friction plates 3 of each brake unit are controlled by a hydraulic actuator to achieve braking action.

[0040] The hydraulic actuator includes a hydraulic control unit 51 and a double-piston brake wheel cylinder 52. The two friction plates 3 in each set of brake units are fixed to the two pistons in the double-piston brake wheel cylinder 52. The hydraulic control unit 51 is provided with a plurality of branches, each of which controls a double-piston brake wheel cylinder 52 separately. When the hydraulic pressure in the double-piston brake wheel cylinder 52 increases, the pistons are pushed and the friction plates thereon are driven to press against the brake disc 1 to apply braking. When the hydraulic pressure in the double-piston brake wheel cylinder 52 decreases, the braking pressure of the friction plates on the brake disc 1 decreases until the braking pressure is zero, and the braking is canceled.

[0041] The hydraulic control unit 51 includes a fluid reservoir 511, a hydraulic pump 512 and a hydraulic accumulator 513. The fluid reservoir 511 is used to store brake fluid, and the hydraulic pump 512 is used to transfer brake fluid to the hydraulic accumulator 513. The hydraulic accumulator 513 is connected to a plurality of branches, each of which is connected to a double-piston brake wheel cylinder 52. A brake fluid circuit is connected to each double-piston brake wheel cylinder 52, and all brake fluid circuits are connected to the fluid reservoir 511 after being collected.

[0042] A liquid inlet solenoid valve 514 is provided on each branch line. One end of the liquid inlet solenoid valve 514 is connected to the hydraulic accumulator 513 through a hydraulic pipeline to receive brake fluid with a certain pressure from the hydraulic accumulator, and the other end is connected to the control double-piston brake wheel cylinder 52 through a hydraulic pipeline. When the liquid inlet solenoid valve is turned on, brake fluid with a certain pressure is introduced into the control double-piston brake wheel cylinder 52.

[0043] Each brake fluid circuit is connected to a liquid outlet solenoid valve 516, one end of which is connected to the fluid storage tank 511 through a hydraulic pipeline. When the liquid outlet solenoid valve 516 is turned on, the brake fluid in the dual-piston brake wheel cylinder 52 flows back to the fluid storage tank, and the fluid pressure in the dual-piston brake wheel cylinder 52 is reduced.

[0044] A hydraulic pressure sensor is provided in the double-piston brake wheel cylinder 52 for closed-loop control of brake pressure and brake torque. A hydraulic pressure sensor 515 is provided on the hydraulic accumulator 513 for detecting the pressure in the hydraulic accumulator 513 as feedback information for pressure control in the hydraulic accumulator 513.

[0045] Taking 10 dual-piston brake wheel cylinders 52 as an example, the single braking load can be calculated based on the braking pressure and braking time of a single brake actuator, and then the cumulative braking load of each brake actuator can be calculated. The five brake actuators on each side of the brake disc select different brake actuator working combination modes according to the required braking torque and the cumulative braking load borne by each brake actuator, so that each brake actuator works in a balanced manner.

[0046] Different brake actuator working combination modes are adopted according to the required braking torque to achieve the same braking action process as the mechanical actuator control, which will not be repeated here.

[0047] The above description is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements without departing from the principle of the present invention, and these improvements should also be regarded as within the protection scope of the present invention.

Claims

1. A dot matrix brake mechanism, comprising a brake disc (1) and a brake caliper body (2), wherein one end of the brake disc (1) is disposed in the brake caliper body (2), and characterized in that: It also includes friction plates (3), wherein two of the plurality of friction plates (3) form a group of brake units, the two friction plates (3) of each group of brake units are symmetrically arranged on both sides of the brake disc (1), and all the friction plates (3) on each side of the brake disc (1) are arranged in an array on the brake caliper body (2); each group of brake units is independently controlled to achieve braking action.

2. The matrix brake mechanism according to claim 1, characterized in that: The friction plates (3) of each set of brake units are controlled by a mechanical actuator to achieve braking action.

3. The matrix brake mechanism according to claim 2, characterized in that: The mechanical actuator comprises a motor (41) and an actuator screw (42); each friction plate (3) is driven by a motor (41) in conjunction with the actuator screw (42); and the two friction plates (3) of each brake unit maintain synchronous movement.

4. The matrix brake mechanism according to claim 2, characterized in that: A brake pressure sensor is provided on the end surface of the friction plate (3) which is away from the brake disc (1).

5. The matrix brake mechanism according to claim 1, characterized in that: The friction plates (3) of each set of brake units are controlled by a hydraulic actuator to achieve braking action.

6. The matrix brake mechanism according to claim 5, characterized in that: The hydraulic actuator comprises a hydraulic control unit (51) and a double-piston brake wheel cylinder (52); two friction plates (3) in each set of brake units are fixed to two pistons in the double-piston brake wheel cylinder (52); a plurality of branches are provided on the hydraulic control unit (51); each branch independently controls a double-piston brake wheel cylinder (52).

7. The matrix brake mechanism according to claim 6, characterized in that: The hydraulic control unit (51) comprises a fluid storage tank (511), a hydraulic pump (512) and a hydraulic accumulator (513); the fluid storage tank (511) is used to store brake fluid; the hydraulic pump (512) is used to transfer brake fluid to the hydraulic accumulator (513); the hydraulic accumulator (513) is connected to a plurality of branches, each branch being connected to a double-piston brake wheel cylinder (52); each double-piston brake wheel cylinder (52) is connected to a brake fluid circuit; all brake fluid circuits are connected to the fluid storage tank (511) after being collected.

8. The matrix brake mechanism according to claim 7, characterized in that: A liquid inlet solenoid valve (514) is provided on each branch line, and a liquid outlet solenoid valve (516) is connected to each brake fluid circuit.

9. The matrix brake mechanism according to claim 6, characterized in that: The hydraulic accumulator (513) is provided with a hydraulic pressure sensor (515), and the double-piston brake wheel cylinder (52) is provided with a hydraulic pressure sensor.

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