Wheel end electronic mechanical braking device

Abstract

The utility model relates to a wheel end electronic mechanical braking device, which belongs to the technical field of automobile wheel end braking, and comprises a braking caliper, a speed reducing mechanism, a driving unit, an energy accumulator and a decoupler, an output shaft of the driving unit is in transmission connection with an input shaft of the speed reducing mechanism, an output shaft of the speed reducing mechanism is in transmission connection with the braking caliper, and the energy accumulator is in transmission connection with the braking caliper. The decoupler is connected with the energy storage device, the decoupler is used for driving the energy storage device to move to be combined with or separated from the driving unit, and the driving unit is used for driving an input shaft of the speed reducing mechanism to rotate, so that a friction plate of the brake caliper is driven to horizontally move to clamp or loosen an automobile brake disc. The speed reducing mechanism has the advantages that the problem of unexpected instability caused by failure of a single-wheel electronic mechanical braking device and / or power supply failure during braking in the driving process is solved through the energy storage device, the machining precision of the speed reducing mechanism can be reduced through the design of the energy storage device, and the process difficulty is reduced.

Description

Technical Field

[0001] This utility model relates to the field of automotive wheel-end braking technology, and in particular to a wheel-end electromechanical braking device. Background Technology

[0002] Wheel-end electromechanical braking systems are commonly used in electric vehicles. Their structure generally includes a motor, a reducer, and brake calipers. The brake calipers contain friction pads that clamp or separate from the brake disc. These friction pads are connected to the brake piston. The reducer's output shaft is connected to the brake piston, and the motor is connected to the reducer's input shaft. During normal vehicle operation, the brakes are applied when the brake pedal is pressed and released when the pedal is released.

[0003] However, existing wheel-end electromechanical braking systems mainly rely on the operation of the motor to drive the friction pads to clamp the brake disc or retract. However, during driving, there may be scenarios where the motor is damaged or malfunctions during braking. Once such a scenario occurs, the residual clamping force between the friction pads corresponding to the damaged motor and the brake disc will affect the stability of the vehicle's continued driving, and in severe cases, it may cause a major accident.

[0004] In addition, due to the requirements of braking performance, the gap between the friction pads and the brake disc cannot be too large or too small (which will affect the braking response rate). The industry also requires that electric vehicles achieve miniaturization of the motor and simplification of the transmission (mainly the reducer). This will impose high standards on the machining precision of the mechanical parts of the transmission, which undoubtedly increases the difficulty of the process and the cost.

[0005] Therefore, it is necessary to develop a wheel-end electromechanical braking device to solve the above-mentioned technical problems. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide a wheel-end electromechanical braking device, which effectively overcomes the defects of the prior art.

[0007] The technical solution of this utility model to solve the above-mentioned technical problems is as follows:

[0008] An electromechanical braking device for wheels includes a brake caliper, a reduction mechanism, a drive unit, an energy storage device, and a decoupler. The output shaft of the drive unit is drivenly connected to the input shaft of the reduction mechanism, and the output shaft of the reduction mechanism is drivenly connected to the brake caliper. The decoupler is connected to the energy storage device. The decoupler is used to drive the energy storage device to move to engage or disengage with the drive unit. The drive unit is used to drive the input shaft of the reduction mechanism to rotate, thereby driving the friction pads of the brake caliper to translate to clamp or release the vehicle brake disc.

[0009] Based on the above technical solution, the present invention can be further improved as follows.

[0010] Furthermore, the aforementioned energy storage device includes a coil spring, a fixing device, and a spindle. The outer end of the coil spring is connected and fixed to the fixing device. The spindle coaxially passes through the center of the coil spring and is connected and fixed to the inner end of the coil spring. The spindle is coaxially arranged with the output shaft of the aforementioned drive unit. The decoupler is movably connected to the spindle and is used to drive the spindle to move to engage or disengage with the output shaft end of the aforementioned drive unit.

[0011] Furthermore, one end of the aforementioned mandrel is coaxially provided with a groove, the output shaft of the aforementioned drive unit extends into the aforementioned groove, and the aforementioned decoupling device is used to drive the aforementioned mandrel to move axially until the output shaft of the aforementioned drive unit abuts or separates from the groove. The bottom surface of the aforementioned groove and the end of the aforementioned drive unit's output shaft are both rough surfaces.

[0012] Furthermore, the decoupler is rotatably connected to the corresponding end of the spindle via a planar bearing.

[0013] Furthermore, the aforementioned decoupler is a solenoid valve push rod.

[0014] Furthermore, a locking structure is provided at the end of the mandrel away from the output shaft of the drive unit. The locking structure is used to lock the mandrel after it is separated from the output shaft of the drive unit.

[0015] Furthermore, the locking structure is a locking pin that is perpendicular to the end of the spindle, and the end of the spindle away from the output shaft of the drive unit is provided with a socket that engages with the locking pin.

[0016] Furthermore, the aforementioned insertion hole is an arc-shaped hole coaxially arranged with the aforementioned mandrel.

[0017] Furthermore, the aforementioned drive unit is a motor.

[0018] Furthermore, the aforementioned decoupler and drive unit are respectively connected to the control system.

[0019] The beneficial effects of this utility model are: the structure is reasonably designed, and the energy storage device solves the problem of unexpected instability caused by the failure of the motor of the single-wheel electromechanical braking device during braking in the driving process, thereby improving the vehicle safety performance. In addition, the design of the energy storage device can reduce the machining precision of the deceleration mechanism and reduce the process difficulty. Attached Figure Description

[0020] Figure 1 This is a simplified diagram showing the structural distribution of the wheel-end electromechanical braking device involved in the wheel-end electromechanical braking device of this utility model;

[0021] Figure 2 This is a schematic diagram of the energy storage device in the wheel-end electromechanical braking device of this utility model;

[0022] Figure 3 This is a schematic diagram of the structure of the energy storage device and the drive unit in the wheel-end electromechanical braking device of this utility model;

[0023] Figure 4 This is a schematic diagram of the structure of the energy storage device and the drive shaft of the drive unit in the wheel-end electromechanical braking device of this utility model.

[0024] Figure 5 This is a schematic diagram of the structure in the wheel-end electromechanical braking device of this utility model, in which the energy storage device and the drive shaft of the drive unit are separated.

[0025] Figure 6 This is a control logic block diagram of the wheel-end electromechanical braking device of this utility model.

[0026] The attached diagram lists the components represented by each number as follows:

[0027] 1. Drive unit; 2. Energy storage device; 3. Decoupling device; 21. Coil spring; 22. Fixing device; 23. Spindle; 24. Locking structure. Detailed Implementation

[0028] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.

[0029] Example

[0030] like Figures 1 to 5 As shown, the wheel-end electromechanical braking device of this embodiment includes a brake caliper (represented by A in the figure), a reduction mechanism (represented by B in the figure), a drive unit 1, an energy storage device 2, and a decoupler 3. The output shaft of the drive unit 1 is drivenly connected to the input shaft of the reduction mechanism (the input shaft of the reduction mechanism is connected to the output shaft of the drive unit 1 through a chain and sprocket transmission structure, which is a conventional transmission structure design and will not be described in detail here). The output shaft of the reduction mechanism is drivenly connected to the brake caliper. The decoupler 3 is connected to the energy storage device 2 and is used for... When the energy storage device 2 is moved to engage or disengage with the drive unit 1, and the drive unit 1 is engaged with the energy storage device 2, the drive unit 1 drives the input shaft of the reduction mechanism to rotate, thereby driving the friction pad of the brake caliper to translate to clamp the vehicle brake disc, and simultaneously drives the energy storage device 2 engaged with it to store energy. When the drive unit 1 fails and / or the power supply fails, the energy storage device 2 drives the drive unit 1 to rotate, thereby driving the friction pad of the brake caliper to translate to disengage from the vehicle brake disc.

[0031] The operating principle of the wheel-end electromechanical braking device in this embodiment is as follows:

[0032] Under normal operating conditions, the output shafts of the energy storage device 2 and the drive unit 1 remain disconnected. During driving, when the brake pedal is depressed, the drive unit 1 drives the input shaft of the reduction mechanism to rotate, thereby causing the brake caliper's friction pads to move and clamp the brake disc. Simultaneously, the energy storage device 2 engages with the output shaft of the drive unit 1, and the drive unit 1 drives the energy storage device 2 to store energy. When the drive unit 1 fails or its power supply fails, the decoupling device 3 is triggered, causing the energy storage device 2 to engage with the drive shaft of the drive unit 1. Driven by the mechanical energy stored in the energy storage device 2, the drive unit 1 rotates in the opposite direction, thereby causing the friction pads to retract rapidly (the output shaft of the drive unit 1 is driven to rotate in the opposite direction by the energy storage device 2, thereby causing the reduction mechanism to run in the opposite direction and causing the friction pads to retract), reducing the residual clamping force between the brake friction pads and the brake disc, ensuring that the vehicle does not lose stability.

[0033] In a preferred embodiment, the energy storage device 2 includes a coil spring 21, a fixing device 22, and a spindle 23. The outer end of the coil spring 21 is connected and fixed to the fixing device 22. The spindle 23 coaxially passes through the center of the coil spring 21 and is connected and fixed to the inner end of the coil spring 21. The spindle 23 is coaxially arranged with the output shaft of the drive unit 1. The decoupling device 3 is movably connected to the spindle 23 and is used to drive the spindle 23 to move to engage or disengage with the output shaft end of the drive unit 1.

[0034] In the above implementation scheme, the fixing device 22 is mainly connected and fixed to the exposed end of the coil spring 21. During energy storage, the spindle 23 engages with the output shaft of the drive unit 1. The drive unit 1 drives the spindle 23 to rotate, thereby causing the coil spring 21 to coil inward and retract, thus storing energy. When the energy storage is full, the torque of the spindle 23 will increase jerkily, which means the torque of the output shaft of the drive unit 1 will also increase jerkily, thereby accurately determining whether the energy storage of the coil spring 21 is full. When the drive unit 1 malfunctions or the power supply fails, the spindle 23 is driven by the decoupling device 3 to move and engage with the output shaft of the drive unit 1. The coil spring 21 releases its "energy" and drives the output shaft of the drive unit 1 to rotate in the opposite direction, realizing the retraction of the friction plate and reducing the residual clamping force between the friction plate and the brake disc. The overall structural design is very reasonable and ingenious.

[0035] In this embodiment, one end of the spindle 23 is coaxially provided with a groove, and the output shaft of the drive unit 1 extends into the groove. The decoupling device 3 is used to drive the spindle 23 axially until the output shaft of the drive unit 1 abuts against or separates from the groove. The bottom surface of the groove and the end of the output shaft of the drive unit 1 are both rough surfaces. The output shaft of the drive unit 1 ( Figure 4The connection between the spindle 11a (represented by [reference]) and the spindle 23 is achieved through frictional contact, resulting in a simpler and easier-to-implement design and more stable transmission. Furthermore, the roughened surface design ensures a tighter bond and more stable transmission.

[0036] In this embodiment, the decoupler 3 is rotatably connected to the corresponding end of the spindle 23 via a plane bearing (represented by 3a in the figure), ensuring that the decoupler 3 can drive the spindle 23 to move axially while the spindle 23 can also meet the performance of good rotation relative to it, thereby realizing the effective energy storage of the energy storage device 2.

[0037] In this embodiment, the decoupler 3 is a solenoid valve push rod. The default state of the solenoid valve is that after the controller connected to it is powered on, the solenoid valve is energized, the push rod is in the extended state, and the spindle 23 abuts against the output shaft end of the drive unit 1. If the energy storage device 2 is full, the decoupler 3 will be disconnected, and the decoupler 3 will drive the spindle 23 to retract and separate from the output shaft end of the drive unit 1.

[0038] Of course, the decoupler 3 mentioned above can also be a cylinder or an electric push rod with good compatibility.

[0039] In a preferred embodiment, the end of the spindle 23 away from the output shaft of the drive unit 1 is provided with a locking structure 24, which is used to lock the spindle 23 after it is separated from the output shaft of the drive unit 1.

[0040] In the above implementation scheme, when the coil spring 21 is fully loaded with energy as it is wound inward, the decoupling device 3 drives the spindle 23 to retract rapidly, so that the spindle 23 is quickly locked with the locking structure 24, thereby suppressing the release of mechanical energy by the "unwinding" of the coil spring 21 and ensuring that the coil spring 21 can retain energy well after it is fully loaded.

[0041] In a preferred embodiment, the locking structure 24 is a locking pin that is perpendicular to the shaft end of the spindle 23, and the end of the spindle 23 away from the output shaft of the drive unit 1 is provided with a socket that engages with the locking pin.

[0042] In the above implementation scheme, the locking structure 24 is designed simply and uses a plug-in method to cooperate with the insertion hole at the end of the spindle 23. After the coil spring 21 has stored energy, the spindle 23 can quickly retract to allow the locking pin to be inserted into the insertion hole, so that the spindle 23 and the coil spring 21 cannot be "unwound" and rotate, thus avoiding failure of mechanical energy storage.

[0043] It should be noted that the fixing device 22 of the energy storage device 2 and the drive unit 1 are both installed in a housing. The fixing device 22 is connected and fixed to the inner wall of the housing, and the locking structure 24 is fixedly installed in the housing.

[0044] In this embodiment, the aforementioned insertion hole is an arc-shaped hole coaxially arranged with the aforementioned spindle 23. Because the spindle 23 is driven back by the decoupling device 3 and separated from the output shaft of the drive unit 1 for a short period of time, and because the state of the spindle 23 when the energy storage device 2 is fully charged is basically fixed, even if the coil spring 21 experiences a slight "unwinding" during retraction, the arc-shaped hole design allows the locking pin to be inserted into the insertion hole even with a slight rotation of the spindle 23, thereby suppressing the energy loss stored in the energy storage device 2. This design is very ingenious.

[0045] In this embodiment, the drive unit 1 uses a motor of an appropriate model.

[0046] In this embodiment, as Figure 6 As shown ( Figure 6 (Y indicates yes, N indicates no). The decoupler 3 and drive unit 1 are respectively connected to the control system. The control system monitors the current changes of drive unit 1 and determines the energy storage status of energy storage device 2 based on the current changes. When energy storage device 2 is fully charged, the control system controls the decoupler 3 to operate and moves energy storage device 2 to separate from drive unit 1. When the power supply to drive unit 1 fails, the control system controls the decoupler 3 to operate and moves energy storage device 2 to reconnect with drive unit 1. The control system uses a compatible ECU (engine control unit). Figure 6 The block diagram describes the operating sequence of the energy storage device 2. After the wheel-end electromechanical braking device is powered on, it detects whether the energy storage device 2 has stored energy. The judgment logic is to detect the torque inflection point of the motor (i.e., the drive unit 1). Because in the design, there is a period of idle stroke before the brake friction pad contacts the brake disc. This idle stroke is used to charge the energy storage device. When the energy storage device 2 is fully charged, the feedback torque value will increase sharply. In this case, the motor will exhibit a torque inflection point. At the same time as the torque inflection point, the motor current will also increase sharply. When the ECU recognizes the motor torque inflection point, it will control the decoupler 3 to operate, causing the spindle 23 to separate from the output shaft of the drive unit 1. The drive unit 1 will then operate normally. When the conditions are met (vehicle in motion, unexpected clamping of EMB, no braking request from the driver, motor-related fault), the ECU will drive the decoupler 3 to operate, causing the spindle 23 to abut against the output shaft end of the drive unit 1. Eventually, the friction pad will return to zero, ensuring that there is no residual clamping force between the friction pad and the brake disc. If the energy storage device 2 is not charged after power-on, it will wait for the driver to press the brake pedal and the motor to start charging.

[0047] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0048] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0049] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0050] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0051] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0052] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A wheel-end electromechanical braking device, characterized in that: The device includes a brake caliper, a reduction mechanism, a drive unit (1), an energy storage device (2), and a decoupler (3). The output shaft of the drive unit (1) is connected to the input shaft of the reduction mechanism, and the output shaft of the reduction mechanism is connected to the brake caliper. The decoupler (3) is connected to the energy storage device (2). The decoupler (3) is used to drive the energy storage device (2) to move to engage or disengage with the drive unit (1). The drive unit (1) is used to drive the input shaft of the reduction mechanism to rotate, thereby driving the friction pads of the brake caliper to move to clamp or release the vehicle brake disc.

2. The wheel-end electromechanical braking device according to claim 1, characterized in that: The energy storage device (2) includes a coil spring (21), a fixing device (22), and a spindle (23). The outer end of the coil spring (21) is fixedly connected to the fixing device (22). The spindle (23) passes coaxially through the center of the coil spring (21) and is fixedly connected to the inner end of the coil spring (21). The spindle (23) is coaxially arranged with the output shaft of the drive unit (1). The decoupling device (3) is movably connected to the spindle (23) and is used to drive the spindle (23) to move to engage or disengage with the output shaft end of the drive unit (1).

3. The wheel-end electromechanical braking device according to claim 2, characterized in that: One end of the mandrel (23) is coaxially provided with a groove, and the output shaft of the drive unit (1) extends into the groove. The decoupling device (3) is used to drive the mandrel (23) to move axially until the output shaft of the drive unit (1) abuts or separates from the groove. The bottom surface of the groove and the end of the output shaft of the drive unit (1) are both rough surfaces.

4. The wheel-end electromechanical braking device according to claim 3, characterized in that: The decoupler (3) is rotatably connected to the corresponding end of the spindle (23) via a planar bearing.

5. The wheel-end electromechanical braking device according to claim 3, characterized in that: The decoupler (3) is a solenoid valve push rod.

6. The wheel-end electromechanical braking device according to claim 5, characterized in that: The mandrel (23) is provided with a locking structure (24) at one end away from the output shaft of the drive unit (1). The locking structure (24) is used to lock the mandrel (23) after it is separated from the output shaft of the drive unit (1).

7. The wheel-end electromechanical braking device according to claim 6, characterized in that: The locking structure (24) is a locking pin that is perpendicular to the shaft end of the spindle (23). The end of the spindle (23) away from the output shaft of the drive unit (1) is provided with a socket that is engaged with the locking pin.

8. The wheel-end electromechanical braking device according to claim 7, characterized in that: The insertion hole is an arc hole coaxially arranged with the mandrel (23).

9. A wheel-end electromechanical braking device according to claim 6, characterized in that: The drive unit (1) is a motor.

10. A wheel-end electromechanical braking device according to claim 9, characterized in that: The decoupler (3) and the drive unit (1) are respectively connected to the control system.

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