An electromechanical brake for a vehicle

Abstract

The application discloses a kind of automobile electronic mechanical brakes, belong to automobile brake technical field;Brake is fixedly connected with suspension through caliper body support, the two brake shoes and brake caliper body of symmetry are installed on the caliper body support;It further includes: servo motor, is fixed at brake caliper body one end by bolt;Planetary reduction mechanism, with thrust piston support connection, for reducing speed ratio, output torque is promoted;Output push rod, one end is connected with planetary reduction mechanism gear, one end is connected with brake caliper body screw thread;The application provides the structure feasible method of automobile electronic mechanical brake, and the force of action of motor is acted to caliper clamping force by planetary reduction mechanism, thrust piston;Control by electromagnet control locking mechanism;When vehicle power system fails or electronic mechanical brake fails, locking structure can be opened by unlocking top rod;Motor angle measurement is realized high-precision rotation angle measurement by optical grating sensor.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic mechanical brake, in particular to an automobile electronic mechanical brake. BACKGROUND

[0002] At present, the most applied product in the prior art is a vacuum booster mechanical brake, which has the following problems: first, the brake pedal decoupling technology cannot be realized, so that when the brake energy is recovered in a new energy automobile, the braking force is inconsistent with the brake pedal stroke, resulting in that the driver cannot obtain stable braking force when operating the brake pedal; second, the brake system cannot realize the function of brake-by-wire (the electronic vacuum booster technology does not belong to the general range due to small market application, and cannot be matched with advanced auxiliary driving technologies such as adaptive cruise control system ACC, automatic emergency braking system AEB, and is not suitable for future automatic driving technology); third, the output braking force is unstable under high and low altitude working conditions due to the vacuum booster principle from atmospheric pressure, and the braking force is lower at higher altitudes. Therefore, the vacuum booster will be eliminated by history.

[0003] In the hydraulic brake system, the brake systems with OneBox and TwoBox architectures are gradually entering the mainstream development trend in the market. However, the brake systems with the two architectures still use corrosive brake fluid as the brake force transmission medium. The brake fluid is a kind of artificially synthesized oil liquid with corrosion, which cannot be naturally degraded in nature, and has great harm to the environment due to large-scale manufacturing and use. At the same time, the brake systems with the two architectures have as many as more than ten hydraulic electromagnetic valves for control, and have complex manufacturing process, high manufacturing cost, very complex oil path structure difficult to maintain, and need to establish a separate failure backup mechanism, and the brake performance is reduced under low temperature conditions.

[0004] The electronic mechanical brake is first applied from the aircraft technology, and many international enterprises have invested in the research and development of EMB technology for automobiles. The reason why it cannot be quickly applied in automobiles is mainly restricted by the structure miniaturization, braking force control precision and structural reliability.

[0005] Therefore, the present application patent aims at the above problems, and an automobile electronic mechanical brake is invented. SUMMARY

[0006] The present application aims to provide an automobile electronic mechanical brake to solve the problems in the background art.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0008] An automobile electromechanical brake, the brake is fixedly connected with the suspension through a caliper bracket, two symmetrical brake shoes are installed on the caliper bracket, the brake shoes are located on both sides of the brake disc, the caliper bracket is inserted with a brake caliper, the brake caliper is installed with a thrust piston, a dust cover and a rectangular ring are installed between the two, and the brake further comprises:

[0009] A servo motor is fixed at one end of the brake caliper through bolts and is used for providing output force to the thrust piston;

[0010] A planetary reduction mechanism is supportedly connected with the thrust piston and is used for reducing speed ratio and improving output torque;

[0011] An output push rod is connected with the planetary reduction mechanism gear at one end and is screw-connected with the brake caliper at one end and is used for converting the output torque of the motor into the axial force of the thrust piston.

[0012] As a further technical scheme of the present application, the planetary reduction mechanism comprises:

[0013] A primary sun gear is connected with the motor shaft through a rectangular spline, one end of the motor shaft is connected with the output end of the servo motor, and the output push rod is movably sleeved on the cylinder of the primary sun gear;

[0014] A primary planetary gear is arranged between the primary sun gear and the thrust piston, and two layers of internal gears are arranged at the bottom of the thrust piston and are respectively meshed with the primary planetary gear and the secondary planetary gear;

[0015] A planet carrier wheel is arranged on the planet carrier wheel through the planet shaft support, the planet carrier wheel supports the primary planetary gear and rotates as a secondary sun gear, and the secondary planetary gear is movably arranged on the output push rod through the planet shaft support;

[0016] A plane thrust bearing is movably sleeved on the primary sun gear, and the planet carrier wheel is movably connected with the plane thrust bearing.

[0017] As a further technical scheme of the present application, a locking mechanism of the thrust piston is arranged between the inside of the thrust piston and the brake caliper.

[0018] As a further technical scheme of the present application, the locking mechanism comprises:

[0019] A locking block is provided with an outer sawtooth thread on one side and can be meshed with an inner sawtooth thread of the thrust piston, and the locking block is controlled by an electromagnet assembly arranged in the brake caliper;

[0020] A locking frame is installed in the brake caliper and is used for fixing and limiting the locking block;

[0021] Locking spring is arranged between locking block and locking rack, and is used for pushing locking block to engage with thrust piston.

[0022] As a further technical scheme of the present application, the electromagnet assembly is composed of an electromagnet coil, an electromagnet stator and an armature, the armature can move axially in the electromagnet under the action of electromagnetic force, one end of the armature is connected with a lever, and the lever is connected with the locking block.

[0023] As a further technical scheme of the present application, a plurality of locking blocks are arranged on the locking rack in a circumferential array, and opposite groups of locking blocks are in the same locking stroke, and there is a meshing stroke difference between an adjacent pair of locking blocks.

[0024] As a further technical scheme of the present application, an unlocking jacking rod is connected to the brake caliper body through threads.

[0025] As a further technical scheme of the present application, a grating encoder is arranged on the motor shaft of the servo motor, and the rotation angle of the motor shaft is measured with high precision by the optical sensor.

[0026] As a further technical scheme of the present application, a controller circuit board is installed between the servo motor and the brake caliper body, the controller circuit board is connected with the electromagnet coil, the terminals of the servo motor and the optical sensor, and is also connected with an external power supply, a wheel speed sensor and a CAN bus.

[0027] Compared with the prior art, the present application has the following advantages: the present application provides a feasible method for the structure of an automotive electromechanical brake, the motor acting force is transmitted to the caliper clamping force through a planetary reduction mechanism and a thrust piston, the locking mechanism can maintain the clamping force of the caliper, the locking mechanism is controlled by an electromagnet, when the vehicle power system fails or the electromechanical brake fails, the locking structure can be opened by an unlocking jacking rod, the motor angle is measured by an optical grating sensor to achieve high-precision angle measurement, the controller circuit board is installed between the locking structure and the servo motor, which can shorten the distance from the electromagnet assembly, the servo motor and the optical sensor, and the assembly of parts is easier. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of an automotive electromechanical brake.

[0029] Figure 2 It is Figure 1 It is a partial enlarged view of A in the middle.

[0030] Reference signs annotation: 1-brake caliper body, 2-caliper body support, 3-brake shoe, 4-brake disc, 5-thrust piston, 6-dust cover, 7-rectangular ring, 8-servo motor, 9-output push rod, 10-first stage sun gear, 11-motor shaft, 12-first stage planetary gear, 13-planetary carrier wheel, 14-second stage planetary gear, 15-locking frame, 16-locking block, 17-locking spring, 18-electromagnet coil, 19-electromagnet stator, 20-armature, 21-lever, 22-unlocking jacks, 23-optical encoder, 24-optical sensor, 25-controller circuit board, 26-flat thrust bearing. DETAILED DESCRIPTION

[0031] The technical solutions of the patent will be further described in detail in combination with specific embodiments.

[0032] As an embodiment of the present application, please refer to Figures 1 to 2 An automotive electromechanical brake, the brake is fixedly connected with the suspension through the caliper body support 2, two symmetrical brake shoes 3 are installed on the caliper body support 2, the brake shoes 3 are located on both sides of the brake disc 4, the dust cover 6 and the rectangular ring 7 are installed between the thrust piston 5 and the brake caliper body 1, when the vehicle brakes or parks, the brake caliper body 1 and the thrust piston 5 jointly form a reaction force to clamp the brake shoes 3 and the brake disc 4 to generate braking torque through friction, further comprising:

[0033] The servo motor 8 is fixed at one end of the brake caliper body 1 through bolts, which is used to provide output force to the thrust piston 5;

[0034] The planetary reduction mechanism is supported and connected with the thrust piston 5, which is used to reduce the speed ratio and improve the output torque;

[0035] The output push rod 9 is connected with the second stage planetary gear 14 of the planetary reduction mechanism at one end and is threadedly connected with the brake caliper body 1 at the other end, which is used to convert the output torque of the motor into the axial force of the thrust piston;

[0036] In the embodiment of the present application, the planetary reduction mechanism comprises:

[0037] The first stage sun gear 10 is connected with the motor shaft 11 through a rectangular spline, when the motor shaft 11 rotates, the first stage sun gear 10 rotates at a constant speed, when the thrust piston 5 moves axially, the motor shaft 11 moves relatively with the first stage sun gear 10, one end of the motor shaft 11 is connected with the output end of the servo motor 8, and the output push rod 9 is movably sleeved on the cylinder body of the first stage sun gear 10;

[0038] Six groups of first stage planetary gears 12 are arranged between the first stage sun gear 10 and the thrust piston 5, two layers of internal gears are arranged at the bottom of the thrust piston 5 and are respectively engaged with the first stage planetary gears 12 and the second stage planetary gears 14;

[0039] The planetary carrier wheel 13 is provided on the planetary carrier wheel 13 through the planetary shaft, and the primary planetary wheel 12 rotates around the primary sun wheel 10 and the thrust piston 5 when the primary sun wheel 10 rotates, and the planetary carrier wheel 13 is pushed to rotate through the planetary shaft. The planetary carrier wheel 13 serves to support the primary planetary wheel 12 and rotates as a secondary sun wheel, and the planetary carrier wheel 13 rotates to rotate the secondary planetary wheel 14 between the thrust piston 5, and the secondary planetary wheel 14 is provided on the output push rod 9 through the planetary shaft, and the output push rod 9 provided with the planetary shaft is pushed to rotate by the secondary planetary wheel 14. Through the secondary planetary reduction mechanism, the rotation torque of the servo motor 8 can be reduced and the output torque can be increased;

[0040] The flat thrust bearing 26 is movably sleeved on the primary sun wheel 10, and the planetary carrier wheel 13 is movably connected with the flat thrust bearing 26.

[0041] In the embodiment of the application, the locking mechanism of the thrust piston 5 is arranged between the inside of the thrust piston 5 and the brake caliper body 1.

[0042] The locking mechanism comprises:

[0043] The locking block 16 is provided with an outer sawtooth thread on one side, which can be engaged with the inner sawtooth thread of the thrust piston 5, and the locking block 16 is controlled by the electromagnet assembly arranged in the brake caliper body 1. When the locking block 16 is engaged with the sawtooth thread of the thrust piston 5, the thrust piston 5 will not be able to retreat;

[0044] The locking block 16 is provided with an outer sawtooth thread on one side, which can be engaged with the inner sawtooth thread of the thrust piston 5, and the locking block 16 is controlled by the electromagnet assembly arranged in the brake caliper body 1. When the locking block 16 is engaged with the sawtooth thread of the thrust piston 5, the thrust piston 5 will not be able to retreat;

[0045] The locking spring 17 is arranged between the locking block 16 and the locking block 15, and is used to push the locking block 16 to engage with the thrust piston 5.

[0046] In the embodiment of the application, the electromagnet assembly is composed of an electromagnet coil 18, an electromagnet stator 19 and an armature 20. The armature 20 can move axially in the electromagnet under the action of electromagnetic force, one end of the armature 18 is connected with a lever 21, and the lever 21 is connected with the locking block 16. When the armature 20 is attracted to the electromagnet stator 19, all the locking blocks 16 can be pulled back, and the thrust piston 5 can freely reciprocate. When the vehicle is in motion or in D, R gear, the electromagnet is in the attracted state. Only when the vehicle is stationary and needs to be parked, the locking block 16 locks the thrust piston 5.

[0047] In the embodiment of the present application, in order to enable the thrust piston 5 to engage with the locking block 16 when moving a small stroke, a plurality of sets of locking blocks 16 are arranged on the locking frame 15, and the locking blocks 16 are arranged in a circumferential array on the locking frame 15, and the locking blocks 16 of opposite sets are of the same locking stroke, and have a difference in engagement stroke with the adjacent pair.

[0048] In the embodiment of the present application, the unlocking jacks 22 are threadedly connected to the brake caliper body 1, and rotating the unlocking jacks 22 can push the levers 21 to release the locking state.

[0049] In the embodiment of the present application, the motor shaft 11 of the servo motor 8 is provided with an optical encoder 23, and the rotation angle of the motor shaft 11 is measured with high precision by the optical sensor 24.

[0050] In the embodiment of the present application, a controller circuit board 25 is installed between the servo motor 8 and the brake caliper body 1, and the controller circuit board 25 is connected with the electromagnet coil 18, the terminals of the servo motor 8 and the optical sensor 24, and is also connected with an external power supply, a wheel speed sensor and a CAN bus.

[0051] It is apparent for those skilled in the art that the present application is not limited to the details of the above-described exemplary embodiments, and the present application can be implemented in other concrete forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all aspects as illustrative and not restrictive, and the scope of the present application is defined by the appended claims rather than the above description, and it is intended to encompass all changes falling within the meaning and range of equivalents of the claims. Any reference signs in the claims should not be considered as limiting the claims involved.

[0052] In addition, it should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that those skilled in the art can understand.

Claims

1. An automotive electromechanical brake, wherein the brake is fixedly connected to the suspension via a caliper bracket, two symmetrical brake shoes are mounted on the caliper bracket, the brake shoes are located on both sides of the brake disc, the caliper bracket is inserted into the brake caliper body, a thrust piston is mounted on the brake caliper body, and a dust cover and a rectangular ring are installed between the brake caliper body and the thrust piston, characterized in that, Also include: Servo motor, fixed by bolts at one end of the brake caliper body, for providing output force to the thrust piston; Planetary reduction mechanism, supported with the thrust piston, for reducing speed ratio and improving output torque; Output push rod, one end connected with the planetary reduction mechanism gear, and the other end connected with the brake caliper body through thread, for converting the output torque of the motor into the axial force of the thrust piston; The planetary reduction mechanism comprises: Primary sun gear, connected with the motor shaft through rectangular spline, one end of the motor shaft connected with the output end of the servo motor, and the output push rod movably sleeved on the cylinder of the primary sun gear; Primary planetary gear, provided between the primary sun gear and the thrust piston, the bottom of the thrust piston provided with two layers of internal gear, respectively engaged with the primary planetary gear and the secondary planetary gear; Planet carrier, the primary planetary gear supported on the planet carrier through planet shaft, the planet carrier serving to support the primary planetary gear and rotate as the secondary sun gear, the secondary planetary gear supported on the output push rod through planet shaft; Flat thrust bearing, movably sleeved on the primary sun gear, the planet carrier movably connected with the flat thrust bearing; The locking mechanism of the thrust piston is provided between the inside of the thrust piston and the brake caliper body; The locking mechanism comprises: Locking block, one side provided with external zigzag thread, engaged with the internal zigzag thread of the thrust piston, the locking block controlled by the electromagnet assembly provided in the brake caliper body; Locking frame, installed in the brake caliper body, the locking frame serving to fix and limit the locking block; Locking spring, provided between the locking block and the locking frame, for pushing the locking block to engage with the thrust piston; A plurality of locking blocks are provided on the locking frame, the locking blocks arranged in circumferential array on the locking frame, the opposite locking blocks of the same locking stroke, and the adjacent locking blocks having engagement stroke difference.

2. An electromechanical brake for a vehicle as defined in claim 1, wherein The electromagnet assembly comprises electromagnet coil, electromagnet stator and armature, the armature axially moving in the electromagnet under the action of electromagnetic force, one end of the armature connected with the lever, and the lever connected with the locking block.

3. The electromechanical brake of claim 1, wherein, The unlocking jacking rod is connected with the brake caliper body through thread.

4. An electromechanical brake for a vehicle as defined in claim 2, wherein The motor shaft of the servo motor is provided with a grating encoder, the rotation angle of the motor shaft measured by the optical sensor.

5. An electromechanical brake for a vehicle as defined in claim 4, wherein The controller circuit board is installed between the servo motor and the brake caliper body, the controller circuit board connected with the electromagnet coil, the terminals of the servo motor and the optical sensor, and further connected with external power supply, wheel speed sensor and CAN bus.

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