Vehicle brake-by-wire mechanism

Abstract

The utility model provides a vehicle brake-by-wire mechanism which enables a brake system to be high in integration degree, accurate in brake force and easy to control and install. The mechanism comprises a lead screw motor assembly, a spring assembly and a brake master cylinder assembly, the lead screw motor assembly comprises a lead screw motor, a motor support and a guide rail. The spring assembly comprises a spring upper end cover, a compression spring, an end cover, a piston and a spring base; the upper end cover of the spring is meshed on a screw rod of the screw rod motor and is limited to rotate through a guide rail mounted on the motor bracket, so that the upper end cover moves left and right on the screw rod; the compression spring is arranged between the spring upper end cover and the spring base and is compressed or restored according to the left-right movement of the spring upper end cover; the piston moves left and right in the cylinder body of the spring base and rubs with the inner wall of the cylinder body so as to reduce vibration of the spring in the braking process. The top of the spring base is provided with an end cover through a screw, piston installation is facilitated, and meanwhile the main cylinder is pulled reversely to release braking force.

Description

TECHNICAL FIELD

[0001] The utility model relates to independent line control brake technology fields, concretely relates to a vehicle line control brake mechanism. BACKGROUND

[0002] With the development of automobile technology, each subsystem of the automobile gradually develops towards the direction of electronization and intelligentization, wherein the line control brake system is gradually concerned, compared with the traditional brake system, the line control brake system uses an electronic control unit to replace the traditional mechanical or hydraulic control, realizes the accurate control of the whole brake system through electric signal transmission, greatly improves the response speed and control precision of the brake system, and has obvious advantages in safety and comfort compared with the traditional brake system. Therefore, the line control brake system has become the mainstream development direction of the new generation of automobile brake system.

[0003] The line control brake system is mainly divided into two types according to different actuators: hydraulic line control brake system (EHB) and mechanical line control brake system (EMB). The EHB system uses electronic equipment to replace the function of part of the traditional mechanical parts, and is equipped with a set of hydraulic backup brake system, which makes it become the mainstream technical choice on the market at present. The EMB system directly generates the required braking force by installing a motor at each wheel, and realizes the stability function such as ABS through the motor control.

[0004] The brake control mechanism system in patent CN110541898A adopts a rack and pinion transmission mechanism; the brake system in patent CN106838129A adopts a worm gear transmission mechanism; the brake control system of Bosch adopts planetary gear train for speed reduction; the motor in patent CN202411086692.6 pushes the master cylinder brake through the planetary gear set and the slider-crank mechanism; the motor shaft and the master cylinder piston of the brake control system of BERTLI are connected through the worm gear and the rack and pinion mechanism. Patent CN201810115168.5 controls the brake wheel cylinder pressure independently by opening the on-off electromagnetic valve; the brake control system of Schaeffler does not have a speed reduction mechanism, and is directly combined through a hollow motor and a ball screw.

[0005] Most of these line control brake mechanisms amplify the motor torque through a speed reduction and torque amplification mechanism, which has the problems of large size, complex structure and sacrifice of transmission efficiency; or the control of braking force depends on the hydraulic system and variable torque motor that can increase the pressure, which needs additional hydraulic system or motor control system, increases the design difficulty, and the control is also correspondingly complicated, thereby increasing the cost and the arrangement difficulty. UTILITY MODEL CONTENTS

[0006] Therefore, the vehicle brake-by-wire mechanism has high integration degree of brake system, accurate brake force and easy control and installation.

[0007] In order to solve the above technical problems, the utility model is realized as follows.

[0008] A vehicle brake-by-wire mechanism, comprising: a screw motor assembly, a spring assembly and a brake master cylinder assembly; the screw motor assembly comprises a screw motor, a motor support and a guide rail; the spring assembly comprises a spring upper end cover, a compression spring, an end cover, a piston and a spring base;

[0009] The spring upper end cover is provided with a first limiting portion and a hollow rod portion; the spring base is provided with a second limiting portion and a cavity; the hollow rod portion penetrates through the end cover and extends into the inner cavity of the spring base; the inner wall of the piston is connected to the end of the spring upper end cover, and the outer wall of the piston is in contact with the inner wall of the spring base to provide friction; the end cover is fixed at the opening of the spring base to constrain the movement of the piston within the inner cavity of the spring base;

[0010] The compression spring is sleeved around the hollow rod portion of the spring upper end cover and the cavity of the spring base and is limited by the first limiting portion and the second limiting portion and compressed or recovered according to the left and right movement of the spring upper end cover;

[0011] The screw rod of the screw motor penetrates into the hollow rod portion from the first limiting portion of the spring upper end cover and is in engagement with the internal thread of the hollow rod portion;

[0012] The guide rail is fixed on the motor support, the spring upper end cover can slide on the guide rail and is constrained from rotating by the connection with the guide rail; the screw motor is fixed on the motor support;

[0013] The spring base is connected to the brake master cylinder assembly.

[0014] Preferably, a gasket is installed at the end of the piston and cooperates with the inner wall of the spring base.

[0015] Preferably, the gasket is a rubber ring and is fixed at the end of the piston by screw connection.

[0016] Preferably, one end of the guide rail is fixed on the motor support, penetrates through the spring upper end cover to constrain the rotation thereof, and the other end of the guide rail is fixed on the other end of the motor support.

[0017] Preferably, one end of the guide rail is fixed on the motor support by screw connection, and the other end of the guide rail is fixed on the other end of the motor support by a guide rail nut.

[0018] Preferably, the guide rail (5) is two.

[0019] Preferably, the motor support is a U-shaped support, one end of which is a long arm for being fixed with the screw motor, and the other end of which is a short arm which does not interfere with the movement of the spring base.

[0020] Preferably, the lead screw motor is fixed with the motor support through 4 groups of motor screws and motor nuts distributed around the lead screw.

[0021] Preferably, the spring base is threadedly connected with the brake master cylinder assembly.

[0022] Preferably, the lead screw motor is a constant torque lead screw motor; the stiffness of the compression spring and the lead screw motor are selected according to the required braking force demand range, braking stroke and maximum braking force.

[0023] Advantages:

[0024] The utility model discloses the advantages of electric control system and hydraulic system, realize the integration and miniaturization of linear brake system, utilize the lead screw motor to push the spring upper end cover, and the compression spring provides linear braking force, realizes linear brake system modularization, can install module in the wheel edge specified position, and the type of key spare parts is reduced greatly, and batch production cost is reduced. The specific advantages are as follows:

[0025] (1) the utility model converts the motor rotation into spring compression, thereby relating the motor movement and braking force, after eliminating the idle stroke, the braking force starts from 0 and is linearly related to displacement, and after the piston reaches the bottom, the braking force is equal to the maximum thrust of the lead screw motor, satisfying the accurate braking demand of the vehicle.

[0026] (2) the constant torque lead screw motor is selected, and the thrust is constant, without complex torque control, only the rotation angle of the motor needs to be controlled.

[0027] (3) the mechanism is simple and reliable. The linear brake improvement can be realized conveniently by utilizing the components of the traditional brake system, and the braking demand and space arrangement demand of the vehicle can be considered simultaneously.

[0028] (4) in a preferred embodiment, the internal friction is increased through the rubber ring, the vibration of the elastic element during braking is reduced, and the braking is more reliable.

[0029] (5) the utility model does not need an additional hydraulic system, reduces the complexity of the overall control mechanism, reduces the volume of the independent brake mechanism, and is convenient to arrange.

[0030] (6) the utility model is high in modularization degree and strong in universality. Only different specifications of threads need to be processed to adapt to various models of brake master cylinders and brake calipers; the stiffness of the spring and the lead screw motor can be selected according to the required braking force demand range, braking stroke and maximum braking force, and adapt to the braking demand of different types of vehicles. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 It is a perspective view of the utility model vehicle linear brake mechanism.

[0032] Figure 2 It is a side view of the vehicle brake-by-wire mechanism.

[0033] Figure 3 It is a sectional view of the vehicle brake-by-wire mechanism.

[0034] Figure 4 It is a three-stage schematic diagram of the vehicle brake-by-wire mechanism in operation.

[0035] Figure 5 It is a control flowchart.

[0036] Figure 6 It is a displacement relationship diagram of the brake force and the spring upper end cover.

[0037] A-screw rod motor assembly; B-spring assembly; C-brake master cylinder assembly; 1-screw rod motor; 2-motor screw; 3-motor support; 4-motor nut; 5-guide rail; 6-guide rail nut; 7-spring upper end cover; 8-compression spring; 9-end cover; 10-rubber ring (washer); 11-end cover screw; 12-piston; 13-spring base. DETAILED DESCRIPTION

[0038] The utility model will be described in detail below in combination with the drawings and examples.

[0039] The utility model embodiment provides a kind of vehicle brake-by-wire mechanism, referring to Figures 1-3 Mainly include screw rod motor assembly A, spring assembly B and brake master cylinder assembly C.Screw rod motor assembly A is mainly by screw rod motor 1, motor support 3, guide rail 5 composition;Spring assembly B is mainly by spring upper end cover 7, compression spring 8, end cover 9, piston 12 and spring base 13 composition.

[0040] Spring upper end cover 7 has first limiting portion and hollow rod portion, two parts are integrated structure.First limiting portion can be discoid, center has through-hole, and is communicated with the through-hole of hollow rod portion.Spring base 13 has second limiting portion and cavity.Hollow rod portion terminal end passes through end cover 9, and extends into the inner chamber of spring base 13;The inner wall of piston 12 is connected at the terminal end of spring upper end cover 7, and the outer wall of piston 12 is in contact with the inner wall of spring base 13;End cover 9 is fixed at the opening of spring base 13, to constrain piston 12 movement in the inner chamber of spring base 13, realize reverse pulling master cylinder, empty brake force.

[0041] Preferably, the end of piston 12 is provided with washer 10, and the inner wall of spring base 13 is matched to increase friction and reduce vibration during braking.Washer 10 can be rubber ring, which is fixed on the end of piston 12 by screw connection, so as to facilitate installation and replacement.

[0042] Preferably, the end cover 9 is fixed at the opening of the spring base 13 by screws, facilitating the installation and maintenance of the piston.

[0043] The compression spring 8 is sleeved on the hollow rod part of the spring upper end cover 7 and the cavity periphery of the spring base 13, and is limited by the first limiting part and the second limiting part; the first limiting part and the second limiting part limit the compression spring through the annular groove as a limiting structure, and limit the compression spring in the radial and axial directions. When the positions of the spring upper end cover 7 and the spring base 13 change relative to each other, the compression spring 8 changes accordingly.

[0044] The lead screw of the lead screw motor 1 penetrates into the hollow rod part from the first limiting part of the spring upper end cover 7 and is engaged with the internal thread of the hollow rod part.

[0045] The guide rail 5 is fixed on the motor support 3, and the spring upper end cover 7 can slide on the guide rail and is restricted from rotating by being connected with the guide rail. In a preferred embodiment, one end of the guide rail 5 is fixed on the motor support 3, penetrates through the spring upper end cover 7 and restricts the rotation of the spring upper end cover 7, and the other end is fixed on the other end of the motor support 3. In this way, no additional connecting structure is needed between the guide rail and the spring upper end cover. When the lead screw rotates, the spring upper end cover 7 is driven to move left and right along the guide rail, thereby compressing the spring. The connection between the guide rail 5 and the motor support 3 can be that one end of the guide rail 5 is fixed on the motor support 3 by screwing, and the other end is fixed on the other end of the motor support 3 by the guide rail nut 6. Preferably, the motor support 3 is a U-shaped support, one end of which is a long arm for being fixed with the lead screw motor 1, and the other end is a short arm which does not interfere with the movement of the spring base 13.

[0046] The lead screw motor 1 is fixed with the motor support 3. Preferably, the lead screw motor 1 is fixed with the motor support 3 by four groups of motor screws 2 and motor nuts 4 which are distributed around the lead screw.

[0047] The working principle of the vehicle line control brake mechanism is as follows:

[0048] The spring upper end cover is engaged on the lead screw of the lead screw motor, and is restricted from rotating by the guide rail installed on the motor support, thereby moving left and right on the lead screw; the compression spring is installed between the spring upper end cover and the spring base, and is compressed or recovered according to the left and right movement of the spring upper end cover; the piston moves left and right in the cylinder of the spring base, and the outer wall is installed with a rubber ring to rub against the inner wall of the cylinder, so as to reduce the vibration of the spring itself during braking; the end cover is installed on the top of the spring base by screws, facilitating the installation of the piston, and simultaneously realizing the reverse pulling of the master cylinder to release the braking force; the spring base assembly is connected with the piston rod of the brake master cylinder through threads, different sizes of threads can be designed to facilitate the connection with different models of master cylinders.

[0049] As shown in Figure 4 , the braking process is divided into the following states:

[0050] In non-braking state, the screw rod motor is static, the piston is in contact with the end cover, the spring is in original length state, the brake master cylinder is free of pressure, and the braking force is 0.

[0051] In braking state, the piston is in contact with the end cover, the spring is in original length state, the brake master cylinder is free of pressure, and the braking force is 0. Figure 5 According to the control flow shown, the screw rod motor rotates by a certain angle according to the braking force, drives the spring upper end cover to move right, and the spring assembly moves right as a whole to eliminate the idle stroke of the brake master cylinder piston, and then compresses the spring to provide the braking force for the brake master cylinder. Figure 6 The relationship between the braking force and the rotation angle of the screw rod motor is related to the spring, the braking force is linearly changed when the linear spring is selected, and the nonlinear spring can be selected according to the braking force requirement.

[0052] In maximum braking state, the piston reaches the bottom of the spring base cylinder body, at this time, the pushing force of the screw rod motor is directly transmitted to the brake master cylinder, and the braking force is equal to the constant pushing force of the screw rod motor.

[0053] The canceling braking process is that the screw rod motor reversely rotates, the spring upper end cover moves left, the braking force decreases, when the piston contacts the end cover, the spring assembly moves left as a whole, the braking force is zero, and the non-braking state is restored.

[0054] The foregoing specific embodiments only describe the design principles of the utility model, the shapes and names of the components in the description can be different, and are not limited. Therefore, the technical personnel in the field of the utility model can modify or equivalently replace the technical solutions recorded in the foregoing embodiments; and the modifications and replacements do not deviate from the purpose and technical solutions of the utility model, and should belong to the protection range of the utility model.

Claims

1. A vehicle brake-by-wire mechanism characterized by comprising: The application relates to a brake master cylinder assembly (C) comprising a screw rod motor assembly (A), a spring assembly (B) and the brake master cylinder assembly (C); the screw rod motor assembly (A) comprises a screw rod motor (1), a motor support (3) and a guide rail (5); the spring assembly (B) comprises a spring upper end cover (7), a compression spring (8), an end cover (9), a piston (12) and a spring base (13). The spring upper end cover (7) is provided with a first limiting part and a hollow rod part; the spring base (13) is provided with a second limiting part and a cavity; the hollow rod part penetrates through the end cover (9) and extends into the cavity of the spring base (13); the inner wall of the piston (12) is connected to the end of the spring upper end cover (7), and the outer wall of the piston (12) is in contact with the inner wall of the spring base (13) to provide friction; the end cover (9) is fixed at the opening of the spring base (13) to restrict the movement of the piston (12) in the cavity of the spring base (13). The compression spring (8) is sleeved on the periphery of the hollow rod part of the spring upper end cover (7) and the cavity of the spring base (13) and is limited by the first limiting part and the second limiting part and is compressed or recovered according to the left and right movement of the spring upper end cover (7). The screw rod of the screw rod motor (1) penetrates into the hollow rod part from the first limiting part of the spring upper end cover (7) and is in engagement with the internal thread of the hollow rod part. The guide rail (5) is fixed on the motor support (3), the spring upper end cover (7) can slide on the guide rail and is restricted from rotating through the connection with the guide rail; the screw rod motor (1) is fixed on the motor support (3). The spring base (13) is connected with the brake master cylinder assembly (C). A gasket (10) is arranged at the end of the piston (12) and cooperates with the inner wall of the spring base (13).

2. The vehicle brake-by-wire mechanism according to claim 1, characterized by, The gasket (10) is a rubber ring and is fixed at the end of the piston (12) through screw connection.

3. The vehicle brake-by-wire mechanism according to claim 2, characterized by, One end of the guide rail (5) is fixed on the motor support (3) and penetrates through the spring upper end cover (7) to restrict the rotation of the spring upper end cover (7), and the other end of the guide rail (5) is fixed on the other end of the motor support (3).

4. The vehicle brake-by-wire mechanism according to claim 1, characterized by, One end of the guide rail (5) is fixed on the motor support (3) through screw connection, and the other end of the guide rail (5) is fixed on the other end of the motor support (3) through a guide rail nut (6).

5. The vehicle brake-by-wire mechanism according to claim 4, characterized by The guide rail (5) is provided with two guide rails.

6. The vehicle brake-by-wire mechanism according to claim 4, characterized by The motor support (3) is a U-shaped support, one end of which is a long arm used for fixing the screw rod motor (1) and the other end of which is a short arm which does not interfere with the movement of the spring base (13).

7. The vehicle brake-by-wire mechanism according to claim 1, characterized by The screw rod motor (1) is fixed on the motor support (3) through four groups of motor screws (2) and motor nuts (4) distributed around the screw rod.

8. The vehicle brake-by-wire mechanism according to claim 1, characterized by, The spring base (13) is connected with the brake master cylinder assembly (C) through screw connection.

9. The vehicle brake-by-wire mechanism according to claim 1, characterized by, The screw rod motor is a constant torque screw rod motor; the stiffness of the compression spring and the screw rod motor are selected according to the required braking force demand range, braking stroke and maximum braking force.

10. The vehicle brake-by-wire mechanism according to claim 1, characterized by ​

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