Electronic mechanical brake structure for brake-by-wire system

Abstract

The invention relates to the technical field of brake-by-wire systems, in particular to an electronic mechanical brake structure for a brake-by-wire system. The caliper body is mounted on the bracket; the transmission mechanism is located in the support and comprises a driving shaft and a ball screw, one end of the driving shaft is arranged in the ball screw and rotationally connected with the ball screw, the outer wall face of the end, located in the ball screw, of the driving shaft and the inner wall face of the ball screw form a containing cavity, and an elastic assembly for driving the ball screw to move towards the driving shaft is arranged in the containing cavity; according to the invention, the driving shaft is matched with the ball screw, the driving shaft rotates to transmit torque to the ball screw, and the ball screw is pushed towards the driving shaft through the matching of the elastic element and the gasket, so that the ball screw and the driving shaft are matched more tightly, and the axial clearance of the ball screw is eliminated, thereby realizing more precise control.

Description

Technical Field

[0001] The present invention relates to the technical field of brake-by-wire systems, and in particular to an electromechanical brake structure used in brake-by-wire systems. Background Art

[0002] The existing electronically controlled mechanical brakes do not have high requirements for braking noise, the brakes are only used for parking, and the application conditions are relatively simple.

[0003] Solution of the prior art: Patent CN216424376U realizes the parking clamping force by adopting a combination of a gear set and a screw. The serrated thread of the screw makes it self-locking. The screw is installed in the brake using only a retaining ring. There is a gap in the screw assembly in the brake. Due to the existence of the gap and idle stroke during the transmission process, it is difficult to achieve precise control, and the linear motion stability is poor.

[0004] Patent CN103373330A uses threads to connect the transmission gear and the screw to achieve the clamping and releasing of the brake. The screw is still installed in a limited position through a retaining ring. There is a movement gap in the screw assembly in the brake, which also makes it difficult to achieve precise control and has poor movement stability.

[0005] Therefore, the present application develops an electromechanical brake structure for a wire-controlled brake system to solve the problems existing in the prior art. Summary of the invention

[0006] The purpose of the present invention is to provide an electronic mechanical brake structure for a wire-controlled brake system to solve the problems in the prior art that the brake has a gap in the transmission process, which makes it difficult to achieve precise control and has poor linear stability.

[0007] The technical solution of the present invention is: an electromechanical brake structure for a wire-controlled brake system, comprising:

[0008] Bracket;

[0009] a caliper body, mounted on the bracket;

[0010] A transmission mechanism is located in the bracket, and the transmission mechanism includes a driving shaft and a ball screw. One end of the driving shaft is arranged in the ball screw and is rotationally connected to the ball screw. The outer wall surface of one end of the driving shaft located in the ball screw and the inner wall surface of the ball screw form a accommodating cavity. An elastic component is provided in the accommodating cavity to drive the ball screw to move toward the driving shaft.

[0011] Preferably, the elastic component comprises an elastic element and a washer, and the elastic element and the washer are both arranged in the accommodating cavity and sleeved on the driving shaft.

[0012] Preferably, the outer wall ring of the driving shaft located at one end of the ball screw is provided with a groove, the groove is located in the accommodating cavity, a C-shaped retaining ring is provided in the groove, the C-shaped retaining ring is sleeved on the driving shaft, and the elastic element and the C-shaped retaining ring are respectively located on both sides of the washer in the axial direction of the driving shaft.

[0013] Preferably, the C-shaped retaining ring, the washer and the elastic element are tightly fitted, and the elastic element abuts against the inner wall surface of the ball screw.

[0014] Preferably, a needle bearing and a plane gasket are sleeved on the drive shaft, one side of the needle bearing contacts the end face of the drive shaft, and the plane gasket contacts the other side of the needle bearing to provide support for the needle bearing.

[0015] Preferably, a pressure sensor is also provided on the driving shaft, and the pressure sensor is sleeved on the driving shaft and fits with the planar gasket.

[0016] Preferably, a bushing is provided at one end of the drive shaft away from the ball screw, and the bushing includes a guide surface and a support surface, the guide surface is in cooperative contact with the outer wall surface of the drive shaft, and the support surface is in cooperative abutment with the caliper body.

[0017] Preferably, a plane ball bearing is provided in the caliper body, and the plane ball bearing is sleeved on the drive shaft. The plane ball bearing is provided with a spring and a limit ring in sequence at one end along the axial direction of the drive shaft and away from the ball screw, and the spring and the limit ring are both arranged on the drive shaft.

[0018] Preferably, the spring abuts against the limiting ring and the plane ball bearing respectively in the axial direction of the driving shaft.

[0019] Compared with the prior art, the advantages of the present invention are:

[0020] (1) The drive shaft and the ball screw cooperate. The drive shaft rotates to transmit torque to the ball screw, and the ball screw is pushed toward the drive shaft through the cooperation of the elastic element and the washer, so that the two cooperate more closely and the axial clearance of the ball screw is eliminated, thereby achieving more precise control;

[0021] (2) The plane ball bearing, spring and limit ring cooperate with each other. The limit ring keeps the spring in a compressed state and maintains the elastic force to press the ball screw and the caliper body tightly, preventing the brake from moving in the air when it is released after clamping, thereby improving the dynamic stability of the brake;

[0022] (3) The elastic element and the washer work together to eliminate the axial clearance of the ball screw, making the ball screw run smoother and improving NVH performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0024] Figure 1 A cross-sectional view of an electromechanical brake structure for a wire-controlled brake system according to the present invention;

[0025] Figure 2 for Figure 1 A magnified structural diagram of the middle part;

[0026] Figure 3 for Figure 1 The enlarged structure of B in the middle;

[0027] Figure 4 It is a cross-sectional view of the installation of the drive shaft and the caliper body of the present invention;

[0028] Figure 5 A three-dimensional diagram of an electromechanical brake structure for a wire-controlled brake system according to the present invention;

[0029] Figure 6 It is an exploded schematic diagram of the transmission mechanism of the present invention.

[0030] Among them: 1. bracket; 2. caliper body; 3. transmission mechanism; 31. drive shaft; 311. groove; 312. C-type retaining ring; 313. end face; 32. ball screw; 4. accommodating chamber; 5. elastic component; 51. elastic element; 52. gasket; 6. needle bearing; 7. flat gasket; 8. pressure sensor; 9. bushing; 91. guide surface; 92. support surface; 10. flat ball bearing; 11. spring; 12. limit ring. DETAILED DESCRIPTION

[0031] The present invention is further described in detail below in conjunction with specific embodiments:

[0032] like Figure 4 As shown, an electronic mechanical brake structure for a wire control brake system includes a bracket 1, a caliper body 2 and a transmission mechanism 3. The caliper body 2 is mounted on the bracket 1 by bolts, and the transmission mechanism 3 is arranged in the bracket 1. The clamping and releasing of the caliper body 2 are controlled by the transmission mechanism 3. During the operation of the transmission mechanism 3, there is a gap in the screw in the brake, resulting in an empty stroke, which makes it difficult to achieve precise control.

[0033] In this embodiment, Figure 1-Figure 3As shown, the transmission mechanism 3 includes a driving shaft 31 and a ball screw 32. One end of the driving shaft 31 is located in the ball screw 32 and is rotatably connected with the ball screw 32. The outer wall surface of the driving shaft 31 at one end of the driving shaft 31 located in the ball screw 32 and the inner wall surface of the ball screw 32 form a receiving chamber 4. An elastic component 5 is provided in the receiving chamber 4. When the driving shaft 31 moves, the driving shaft 31 transmits torque to the ball screw 32. The elastic component 5 abuts against the inner wall surface of the ball screw 32. When the elastic component 5 is deformed by force, the ball screw 3 is pushed. 2 moves in the direction of the drive shaft 31, thereby reducing the space of the accommodating chamber 4, so that the ball screw 32 and the drive shaft 31 are closely matched, and the transmission accuracy of the ball screw 32 is high, which can ensure that the ball screw 32 can accurately and stably move to the specified position under the push of the elastic component 5, thereby improving the positioning accuracy of the entire braking system, and can eliminate the gap in the transmission process, improve the axial rigidity, and under the push of the elastic component 5, the ball screw 32 can be closely fitted on the drive shaft 31, ensuring the accuracy and stability of the transmission.

[0034] The elastic component 5 includes an elastic element 51 and a washer 52, both of which are sleeved on the drive shaft 31 and located in the accommodating chamber 4. The elastic element 51 is, but not limited to, an elastic part such as a wave spring 11, a disc spring 11, a cylindrical spring 11, or a spring sheet. Preferably, the elastic element 51 is a wave spring 11, which can compensate for the gap between the ball screw 32 and the drive shaft 31 due to manufacturing tolerances, wear, or thermal deformation, thereby ensuring a tight connection between the two and preventing vibration and noise caused by excessive gaps. By eliminating or reducing the connection The gap enhances the stability during transmission, reduces transmission errors, improves transmission accuracy, and makes the operation of the brake more stable and reliable. In addition, by adjusting the compression amount of the wave spring 11, the preload force between the ball screw 32 and the drive shaft 31 can be controlled to ensure that the transmission system can maintain appropriate tightness under different working conditions. During the braking process, the action of the wave spring 11 makes the transmission system more stable and reliable, which helps to improve the overall performance of the brake and ensure that the vehicle or equipment can brake quickly and accurately when needed, while the washer 52 provides support for the wave spring 11.

[0035] In order to make the elastic element 51 always maintain elastic force, a groove 311 is provided on the outer wall surface of the driving shaft 31 at one end of the ball screw 32, and the groove 311 is located in the accommodating chamber 4, and a C-shaped retaining ring 312 is installed in the groove 311. The C-shaped retaining ring 312 is sleeved on the driving shaft 31 and is located on both sides of the gasket 52 with the elastic element 51. The design of the groove 311 provides an accurate installation position for the C-shaped retaining ring 312, ensuring that the retaining ring can be firmly installed on the driving shaft 31 and is not easy to loosen or fall off. Through the axial positioning of the C-shaped retaining ring 312 and the clearance compensation effect of the wave spring 11, the ball screw 32 and the driving shaft 31 are reduced. The transmission error between the moving shaft 31 improves the transmission accuracy. The anti-loosening function of the C-type retaining ring 312 and the shock-absorbing effect of the wave spring 11 jointly enhance the stability of the entire ball screw 32 mechanism, so that it can operate stably under high speed or high load conditions. The C-type retaining ring 312, the washer 52 and the elastic element 51 fit tightly, and the elastic element 51 abuts against the inner wall surface of the ball screw 32, which provides additional stability during the transmission process, ensuring that the ball screw 32 can still maintain a precise axial position under high speed or high load conditions, and can further reduce the space of the accommodating chamber 4 and the gap between the ball screw 32 and the driving shaft 31.

[0036] Furthermore, if Figure 5-Figure 6 As shown, a needle bearing 6 and a flat gasket 7 are provided on the drive shaft 31. One side of the needle bearing 6 is in contact with the end face 313 of the drive shaft 31, and the flat gasket 7 is in contact with the other side of the needle bearing 6. The needle bearing 6 replaces the sliding friction with rolling friction, which significantly reduces the friction and wear. The low friction characteristics of the needle bearing 6 enable it to be used in high-speed brakes, so that the drive shaft 31 rotates smoothly and moves more smoothly. The flat gasket 7 is used to adjust the gap and ensure the accurate positioning of the bearing, which helps to maintain the overall stability and accuracy of the brake and prevent performance degradation due to excessive gap or bearing position offset. The flat gasket 7 can disperse the pressure between the needle bearing 6 and the drive shaft 31 and reduce component damage caused by excessive local pressure. At the same time, the flat gasket 7 can also serve as a protective layer to prevent direct contact and wear between the needle bearing 6 and the drive shaft 31.

[0037] In order to monitor the thrust of the brake in real time, a pressure sensor 8 is provided on the drive shaft 31. The pressure sensor 8 is sleeved on the drive shaft 31 and fits with the flat gasket 7. The pressure sensor 8 is in close contact with the flat gasket 7 to accurately sense the pressure changes in the braking system and convert these changes into electrical signal outputs.

[0038] Furthermore, a bushing 9 is provided at one end of the drive shaft 31 away from the ball screw 32, and the bushing 9 includes a guide surface 91 and a support surface 92. The guide surface 91 is in fitting contact with the outer wall surface of the drive shaft 31, and the support surface 92 is in fitting abutment with the caliper body 2. The guide surface 91 is in tight fitting contact with the outer wall surface of the drive shaft 31, providing precise guidance for the rotation of the drive shaft 31, ensuring that the drive shaft 31 can maintain a stable trajectory during rotation, reducing the friction between the drive shaft 31 and the bushing 9, reducing energy loss, and improving transmission efficiency. The support surface 92 is in fitting abutment with the caliper body 2, providing a stable supporting force for the caliper body 2, ensuring that the caliper body 2 can maintain a stable position during braking.

[0039] In order to further reduce the movement resistance, make the driving shaft 31 rotate more smoothly, and ensure smooth movement, a plane ball bearing 10, a spring 11, and a limit ring 12 are provided in the caliper body 2, and the caliper body 2 is evenly provided with a plane ball bearing 10, a spring 11, and a limit ring 12, and the plane ball bearing 10 and the limit ring 12 are respectively located on both sides of the spring 11 in the axial direction of the driving shaft 31, and abut against the spring 11. The spring 11 is but not limited to a wave spring 11, a disc spring 11, a cylindrical spring 11, a spring sheet and other elastic parts. Preferably, the spring 11 is a butterfly spring 11, and the butterfly spring 11 is subjected to force to generate thrust to press the ball screw 32 against the caliper body 2. The limit ring 12 is located on the other side of the spring 11 to limit the axial direction of the driving shaft 31 to ensure that they do not exceed the predetermined range of motion, and at the same time compress the spring 11 to generate elastic force and maintain the elastic force.

[0040] The implementation principle of this embodiment:

[0041] During the operation of the brake, the drive shaft 31 rotates to transmit the torque to the ball screw 32. The ball screw 32 runs, and the ball screw 32 cooperates with the drive shaft 31 to form a receiving chamber 4. The receiving chamber 4 is provided with a wave spring 11 and a washer 52, which cooperate with the C-shaped retaining ring 312. The wave spring 11 is deformed by force and generates thrust, which pushes the ball screw 32 toward the direction of the drive shaft 31 to reduce the gap between the two and eliminate the axial clearance of the ball screw 32 during the rotation process, thereby achieving more precise control. The lever 32 runs more smoothly and has better NVH performance. The planar ball bearing 10, butterfly spring 11 and limit ring 12 mounted on the drive shaft 31 cooperate with each other. The limit ring 12 keeps the butterfly spring 11 elastic and generates thrust to press the ball screw 32 against the caliper body 2, thereby reducing the movement resistance and making the drive shaft 31 rotate more smoothly. The bushing 9 arranged on the drive shaft 31 provides guidance for the drive shaft 31 to ensure the stability of the rotation of the drive shaft 31, and provides support for the caliper body 2 to ensure that the caliper body 2 maintains a stable position during braking.

[0042] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the scope of protection of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention.

Claims

1. An electromechanical brake structure for a wire control brake system, characterized in that: include: Bracket (1); A caliper body (2) mounted on the bracket (1); A transmission mechanism (3) is located in the bracket (1), and the transmission mechanism (3) comprises a drive shaft (31) and a ball screw (32). One end of the drive shaft (31) is arranged in the ball screw (32) and is rotatably connected to the ball screw (32). The outer wall surface of one end of the drive shaft (31) located in the ball screw (32) and the inner wall surface of the ball screw (32) form a receiving cavity (4). An elastic component (5) is provided in the receiving cavity (4) for driving the ball screw (32) to move toward the drive shaft (31).

2. The electromechanical brake structure for a wire control brake system according to claim 1, characterized in that: The elastic component (5) comprises an elastic element (51) and a washer (52); the elastic element (51) and the washer (52) are both arranged in the accommodating cavity (4) and sleeved on the driving shaft (31).

3. The electromechanical brake structure for a wire control brake system according to claim 2, characterized in that: A groove (311) is provided on the outer wall of one end of the drive shaft (31) located at the ball screw (32); the groove (311) is located in the accommodating cavity (4); a C-shaped retaining ring (312) is provided in the groove (311); the C-shaped retaining ring (312) is sleeved on the drive shaft (31); and the elastic element (51) and the C-shaped retaining ring (312) are respectively located on both sides of the washer (52) in the axial direction of the drive shaft (31).

4. The electromechanical brake structure for a wire control brake system according to claim 3, characterized in that: The C-shaped retaining ring (312), the washer (52) and the elastic element (51) are tightly fitted, and the elastic element (51) is in contact with the inner wall surface of the ball screw (32).

5. The electromechanical brake structure for a wire control brake system according to claim 1, characterized in that: The drive shaft (31) is sleeved with a needle bearing (6) and a plane gasket (7); one side of the needle bearing (6) is in contact with the end surface (313) of the drive shaft (31), and the plane gasket (7) is in contact with the other side of the needle bearing (6) to provide support for the needle bearing (6).

6. The electromechanical brake structure for a wire control brake system according to claim 5, characterized in that: The driving shaft (31) is also provided with a pressure sensor (8), and the pressure sensor (8) is sleeved on the driving shaft (31) and fits with the planar gasket (7).

7. The electromechanical brake structure for a brake-by-wire system according to claim 1, characterized in that: A bushing (9) is provided at one end of the drive shaft (31) away from the ball screw (32), and the bushing (9) includes a guide surface (91) and a support surface (92), the guide surface (91) is in cooperative contact with the outer wall surface of the drive shaft (31), and the support surface (92) is in cooperative abutment with the caliper body (2).

8. The electromechanical brake structure for a brake-by-wire system according to claim 1, characterized in that: A plane ball bearing (10) is provided in the caliper body (2), and the plane ball bearing (10) is sleeved on the drive shaft (31). A spring (11) and a limit ring (12) are provided in sequence on one end of the plane ball bearing (10) along the axial direction of the drive shaft (31) and away from the ball screw (32). The spring (11) and the limit ring (12) are both arranged on the drive shaft (31).

9. The electromechanical brake structure for a wire control brake system according to claim 8, characterized in that: The spring (11) is in abutment with the limiting ring (12) and the plane ball bearing (10) respectively in the axial direction of the driving shaft (31).

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