Brake caliper with reduced volume

Abstract

The present invention provides a brake caliper with a reduced volume. The brake caliper includes a brake caliper body (2), a motion conversion mechanism (5), and an anti-rotation mechanism (6). The motion conversion mechanism (5) includes a rotating member (3) and a translating member (4). The anti-rotation mechanism (6) includes an anti-rotation boss (4a) provided on the outer wall of the translating member (4) and an anti-rotation groove (2b) provided on the inner wall of the cylinder hole (2a) of the brake caliper body (2). The anti-rotation groove (2b) fits into the anti-rotation boss (4a) to limit the rotation of the translating member (4). By optimizing the anti-rotation structure of the motion conversion mechanism, this brake caliper can reduce the axial dimension of the caliper and facilitate processing.

Description

Technical Field

[0001] The present invention belongs to the technical field of braking systems, and specifically relates to a brake caliper with reduced volume.

Background Art

[0002] Conventional hydraulic calipers require a piston structure to convert hydraulic pressure into thrust. In an electric control brake dry caliper, the hydraulic brake mode is abolished, and full electric drive is adopted, and the brake pads can be directly pressed by a motion conversion mechanism.

[0003] The electric control brake caliper in the prior art retains a piston structure. The patent document with publication number CN107076237A discloses an electromechanical brake caliper actuator, and the piston of the electromechanical brake caliper actuator has the following functions.

[0004] 1. Anti-rotation function: The anti-rotation structure of this solution provides a long groove on the outer wall of the piston, drills a hole in the side wall of the caliper body, attaches a screw, and the screw penetrates the caliper body and is inserted into the groove on the outer wall of the piston to limit the rotation of the piston and the nut.

[0005] 2. Sealing function: The piston fits into the inner wall of the cylinder hole of the caliper body, and a ring and a dust cover are attached between the piston and the cylinder hole for sealing.

[0006] The electromechanical brake caliper actuator described above has a problem in that the axial dimensions of the piston are increased due to the anti-rotation structure and sealing structure. The length of the anti-rotation groove provided on the outer wall of the piston must be greater than the total amount of wear of components such as brake discs and brake pads over the entire lifespan. In other words, it must be greater than the total stroke over the piston's lifespan; otherwise, the anti-rotation function may fail. Next, within the total stroke of the piston, if the groove of the piston comes into contact with the position of the ring in the cylinder bore, the seal may fail. Therefore, the length of the piston must be greater than at least twice the total stroke length. Consequently, the axial dimensions of the piston and the brake caliper assembly become larger, making installation in the finished vehicle more difficult.

[0007] A patent document with publication number CN113906233A describes another anti-rotation method, in which a screw attached to the piston is fitted into a groove on the inner wall of the cylinder bore to prevent rotation, and the piston length can be shortened by matching the seal structure with that of a conventional caliper. However, in this method, the caliper body is designed as a split structure in order to machine the anti-rotation groove in the cylinder bore, and furthermore, the two split caliper bodies need to be connected with screws, which makes the structure complex and increases the volume and weight.

[0008] As described above, conventional brake calipers have the following problems.

[0009] 1) In order to ensure both the stroke for preventing rotation and the stroke for sealing, the axial dimension of the piston increases, which increases the overall length of the brake caliper and makes spatial placement difficult.

[0010] 2) In order to reduce the axial dimension, the caliper body needs to be designed with a segmented structure, which makes the structure complex and difficult to manufacture. [Overview of the project] [Problems that the invention aims to solve]

[0011] This invention was made to solve at least one of the technical problems of the prior art, and the object of this invention is to provide a brake caliper with reduced volume that reduces the axial dimension of the brake caliper and facilitates machining. [Means for solving the problem]

[0012] To achieve the above objective, the present invention employs the following technical means: A brake caliper with reduced volume, comprising a brake caliper body, a motion conversion mechanism, and a rotation prevention mechanism, wherein the motion conversion mechanism comprises a rotating member and a translation member, and the rotation prevention mechanism comprises a rotation prevention boss provided on the outer wall of the translation member and a rotation prevention groove provided on the inner wall of the cylinder bore of the brake caliper body, wherein the rotation prevention groove fits into the rotation prevention boss to restrict the rotation of the translation member.

[0013] An opening is provided at one end of the translational member through which the rotating member passes, and the anti-rotation boss is positioned close to the opening on the outer wall of the translational member.

[0014] The translational member is cup-shaped, with one end open and the other end closed, and the cross-section of the translational member is U-shaped.

[0015] The cup-shaped bottom and cup-shaped outer wall of the rotating member and / or translational member are integrally formed.

[0016] The cup-shaped bottom and cup-shaped outer wall of the rotating member and / or translational member are connected by welding, riveting, or screwing.

[0017] A first ring groove is provided in the cylinder bore, and a ring is provided in the first ring groove.

[0018] At least one of the aforementioned rings is provided.

[0019] The anti-rotation groove is an arc groove, and the maximum distance between the anti-rotation groove and the axis of the cylinder hole is smaller than the minimum radius of the first ring groove.

[0020] The brake caliper with reduced volume further includes a dust cover located between the brake caliper body and the translation member.

[0021] A position limiting mechanism is provided between the rotating member and the translation member, and the position limiting mechanism is a pair of position limiting bosses that fit into each other.

Advantages of the Invention

[0022] The brake caliper of the present invention can reduce the axial dimension of the caliper and facilitate processing by optimizing the anti-rotation structure of the motion conversion mechanism. In addition, between the motion conversion mechanism and the caliper body, a sealing function and an anti-rotation function can be realized, the transmission structure can be simplified, and the number of parts can be reduced.

Brief Description of the Drawings

[0023] [[ID=​​​​​​​​​​​​​​​​​​​As shown in Figures 1 to 3, the present invention provides a brake caliper with reduced volume. The brake caliper includes an actuator 1, a brake caliper body 2, a motion conversion mechanism, and a rotation prevention mechanism 6, the motion conversion mechanism and the rotation prevention mechanism 6 being located in the cylinder bore 2a of the brake caliper body 2, and the motion conversion mechanism including a rotating member 3 and a translational member 4. The output shaft of actuator 1 is connected to the rotating member 3 of motion conversion mechanism 5. Motion conversion mechanism 5 converts the torque and rotational speed of the rotating member 3 into linear motion and thrust of the translational member 4, directly pressing the brake pads and clamping the brake disc 11. The anti-rotation mechanism 6 includes an anti-rotation boss 4a provided on the outer wall of the translational member 4 and an anti-rotation groove 2b provided on the inner wall of the cylinder hole 2a of the brake caliper body 2. The anti-rotation groove 2b fits into the anti-rotation boss 4a to restrict the rotation of the translational member 4.

[0026] This brake caliper has the following advantages:

[0027] 1. Simplify the transmission structure and reduce the number of parts. This invention presents an example in which a ball screw is selected as the motion conversion mechanism 5. The inner wall of the translational member 4 is provided with a screw track for inserting a ball, and the outer wall of the rotating member 3 is also provided with a screw track for inserting a ball. The translational member 4 and the rotating member 3 constitute a ball screw, and the translational member 4 combines the functions of a piston and a nut.

[0028] A rotation-preventing boss 4a is provided on the outer wall surface of the translational member 4. The rotation-preventing boss 4a engages with a rotation-preventing groove 2b provided on the inner wall of the cylinder hole 2a of the brake caliper body 2, thereby forming a rotation-preventing mechanism 6. A ring and a dust cover 8 are installed between the translational member 4 and the cylinder hole 2a, forming a sealing mechanism.

[0029] Next, it is preferable to integrally mold the cup-shaped rotating member 3 and the translational member 4 using processes such as casting and cold extrusion.

[0030] In this invention, by using a ball screw, it is possible to replace the piston in conventional technology, integrate sealing and anti-rotation functions, simplify the transmission structure, and reduce the number of parts.

[0031] 2. Reduce the axial dimension of the caliper. The conventional anti-rotation mechanism 6 has the following problems. 1) In order to ensure both the stroke for preventing rotation and the stroke for sealing, the axial dimension of the piston increases, which increases the overall length of the brake caliper and makes spatial placement difficult. 2) In order to reduce the axial dimension, the caliper body must be designed with a split structure, which makes the structure complex and difficult to manufacture.

[0032] In this invention, a ring groove is provided at the end of the rotating member 3, allowing a bearing 9 to be attached and reducing the mounting height of the bearing 9. A rotation-preventing boss 4a is provided on the outer wall surface of the translational member 4. A rotation-preventing groove 2b is machined into the inner wall of the cylinder bore 2a, and the rotation-preventing boss 4a fits into the rotation-preventing groove 2b to restrict the rotation of the translational member 4. The length of the rotation-preventing groove 2b can be directly matched with the length of the cylinder bore 2a, and the longitudinal direction of the rotation-preventing groove 2b and the rotation-preventing boss 4a is parallel to the axis of the cylinder bore 2a. The difference in length between the rotation-preventing groove 2b and the rotation-preventing boss 4a must be greater than the total axial displacement during the lifespan of the translational member 4, ensuring that the rotation of the translational member 4 is always restricted.

[0033] In this invention, a conventional one-piece caliper body is employed, with a first ring groove 2c machined into the end of the cylinder bore 2a, and the ring 7 is attached to the first ring groove 2c. The anti-rotation groove 2b is perpendicular to the first ring groove 2c. The maximum distance between the anti-rotation groove 2b and the axis of the cylinder bore 2a is smaller than the minimum radius of the first ring groove 2c, ensuring that the outer wall of the ring 7 is in close contact with the first ring groove 2c after the ring 7 is attached. Furthermore, the outer wall of the translational member 4, excluding the anti-rotation boss 4a and the first ring groove 2c, is similar to a bare shaft (a columnar body with a smooth surface), and by ensuring that the inner wall of the ring 7 is in close contact with the outer wall of the translational member 4, sealing performance throughout its lifespan is guaranteed.

[0034] With the above configuration, the anti-rotation stroke and the seal stroke are arranged to overlap, and the bearing 9 and the rotating member 3 are arranged to overlap in the axial direction, thereby ensuring the sealing function and anti-rotation function within the full stroke, while also reducing the axial dimension of the translation member 4.

[0035] The following will be explained based on specific examples.

[0036] As shown in Figures 1 to 3, this embodiment provides a brake caliper with reduced volume. The brake caliper includes an actuator 1, an inner pad 10, an outer pad 12, a brake caliper body 2, a motion conversion mechanism, and a rotation prevention mechanism 6. The motion conversion mechanism includes a rotating member 3 and a translational member 4, and the rotation prevention mechanism 6 includes a rotation prevention boss 4a provided on the outer wall of the translational member 4 and a rotation prevention groove 2b provided on the inner wall of the cylinder bore 2a of the brake caliper body 2. The rotation prevention groove 2b is fitted into the rotation prevention boss 4a and restricts the rotation of the translational member 4. The translational member 4 and the rotating member 3 constitute a ball screw, with the translational member 4 performing linear motion in the axial direction and the rotating member 3 performing rotational motion. The translational member 4 and the rotating member 3 are located in the cylinder bore 2a of the brake caliper body 2. The inner pad 10 and the outer pad 12 are located on both sides of the brake disc 11. The translational member 4 is used to press against the inner pad 10 during braking, thereby moving the inner pad 10 toward the brake disc 11.

[0037] As shown in Figure 1, the actuator 1 is installed on the brake caliper body 2 and is used to rotate the rotating member 3. The actuator 1 includes at least a motor and a reduction mechanism. The configuration of the actuator 1 is well known to those skilled in the art and will not be described here.

[0038] As shown in Figure 1, the brake caliper body 2 has an integrated structure and is provided with a cylinder bore 2a. An arc-shaped anti-rotation groove 2b is machined into the side wall of the cylinder bore 2a, and the axial cross-sectional shape of the cylinder bore 2a is roughly trumpet-shaped, with the diameter decreasing as the cylinder bore 2a approaches the actuator 1 and increasing as the cylinder bore 2a approaches the brake pad. A first ring groove 2c is machined into the end of the cylinder bore 2a, and a ring 7 is attached to the first ring groove 2c. The radius of the first ring groove 2c is greater than the maximum distance between the anti-rotation groove 2b and the axis of the cylinder bore 2a.

[0039] As shown in Figure 1, the motion conversion mechanism 5 includes at least a rotating member 3 and a translational member 4, and in this embodiment, the motion conversion mechanism 5 uses a ball screw. The rotating member 3 is a screw shaft, and the translational member 4 is a piston. A screw track is provided on the inner wall of the translational member 4, and the translational member 4 and the rotating member 3 constitute a ball screw. In this embodiment, the translational member 4 is cup-shaped, with one end open and the other end closed, and the cross-section of the translational member 4 is U-shaped. A position limiting mechanism is provided between the rotating member 3 and the translational member 4, and the position limiting mechanism is a pair of position limiting bosses that fit together. The pair of position limiting bosses that fit together include a first position limiting boss 3a provided at the end of the rotating member 3 away from the actuator 1, and a second position limiting boss 4b provided in the inner hole of the translational member 4 and close to the closed end of the translational member 4. The position where the first position limiting boss 3a and the second position limiting boss 4b contact is the zero position (reference position) of the translational member 4 relative to the rotating member 3, where the brake caliper cannot generate braking force.

[0040] As shown in Figure 1, the output shaft of the actuator 1 is directly connected to the rotating member 3 to transmit torque and rotational speed. A bearing 9 is installed between the rotating member 3 and the bottom of the cylinder bore 2a of the caliper body. The bearing 9 may be a thrust needle bearing. A third ring groove is provided at the end of the rotating member 3, and this third ring groove is located at one end of the rotating member 3 that is close to the bottom of the cylinder bore 2a. The bearing 9 can be installed in the third ring groove, which can reduce the axial height of the entire caliper. The outer wall of the translational member 4 fits directly into the inner wall of the cylinder bore 2a of the brake caliper body 2, and the translational member 4 corresponds to the piston in a conventional caliper structure.

[0041] The anti-rotation mechanism 6 plays a role in limiting the rotation of the translational member 4 within the full stroke of the piston's translational motion. As shown in Figures 1 to 3, the anti-rotation mechanism 6 includes an anti-rotation boss 4a and an anti-rotation groove 2b that fit together. The anti-rotation boss 4a is provided on the outer wall of the translational member 4 and is close to the open end of the translational member 4. The anti-rotation groove 2b is provided on the inner wall of the cylinder bore 2a of the caliper body. The shape of the anti-rotation groove 2b is arc-shaped, and the length of the anti-rotation groove 2b can match the length of the cylinder bore 2a. The difference in length between the anti-rotation groove 2b and the anti-rotation boss 4a, i.e., the total length over which the rotation of the translational member 4 is restricted, must be greater than the total axial stroke over the lifespan of the translational member 4. There is at least one anti-rotation mechanism 6.

[0042] The anti-rotation boss 4a is machined and molded integrally with the translation member 4. Alternatively, the anti-rotation boss 4a can be attached to the translation member 4 by fixing methods such as crimping or welding.

[0043] The anti-rotation groove 4b is fixed to the cylinder bore of the brake caliper body 2 and can be formed by machining or casting. In the case of machining, it can be cut from the flange of the brake caliper body, and after machining is complete, a steel ball can be press-fitted into the flange bore to form a seal.

[0044] As shown in Figure 1, the role of the sealing mechanism is to ensure sealing between the translational member 4 and the brake caliper body 2 within the total axial stroke of the piston. The sealing mechanism includes at least one ring 7 and a dust cover 8, the ring 7 and dust cover 8 covering the translational member 4. In the axial direction of the cylinder bore 2a, the ring 7 is located between the dust cover 8 and the anti-rotation groove 2b. A first ring groove 2c is machined at the end of the cylinder bore 2a, and the anti-rotation groove 2b and the first ring groove 2c are perpendicular to each other. The maximum distance between the anti-rotation groove 2b and the axis of the cylinder bore 2a is smaller than the minimum radius of the first ring groove 2c, so the ring 7 is mounted in the first ring groove 2c and the outer wall of the ring 7 can be brought into close contact with the first ring groove 2c. The width of the ring 7 is greater than the width of the anti-rotation groove 2b, so the inner wall of the ring 7 is in close contact with the outer wall of the translational member 4. In this embodiment, both the ring 7 and the dust cover 8 have a metal skeleton, and the ring 7 is crimped into the first ring groove 2c, thereby simplifying the structure of the ring groove.

[0045] The number of rings 7 is at least one, and if two rings 7 are installed, or if the rings 7 are relatively wide, that is, if the axial dimension is large, they can serve a good positioning and guiding role for the translational member 4.

[0046] The above has been an illustrative description of the present invention in conjunction with the drawings. It is clear that the present invention is not limited to the above-described methods when it is specifically implemented. Various non-substantial improvements made by adopting the methods, concepts and technical means of the present invention, or direct applications of the above-described concepts and technical means of the present invention in other contexts without modification, are all within the scope of protection of the present invention. [Explanation of symbols]

[0047] 1 Actuator 2 Brake caliper body 2a Cylinder bore 2b Anti-rotation groove 2c First ring groove 3 Rotating member 3a First position restricted boss 4 Translational members 4a Anti-rotation boss 4b Second Position Restricted Boss 4c Second ring groove 5. Motion conversion mechanism 6. Anti-rotation mechanism 7 Rings 8 Dust cover 9 bearings 10 Inner Pads 11 Brake discs 12 Outpad

Claims

1. The brake caliper body includes a motion conversion mechanism and a rotation prevention mechanism, the motion conversion mechanism having a rotating member and a translation member, and the rotation prevention mechanism includes a rotation prevention boss provided on the outer wall of the translation member and a rotation prevention groove provided on the inner wall of the cylinder bore of the brake caliper body. The rotation prevention groove is designed to fit the rotation prevention boss and restrict the rotation of the translation member. A first ring groove is provided in the cylinder bore, and a ring is provided in the first ring groove, A brake caliper with reduced volume, characterized in that the anti-rotation groove is an arc groove, and the maximum distance between the anti-rotation groove and the axis of the cylinder bore is smaller than the minimum radius of the first ring groove.

2. The brake caliper with reduced volume according to claim 1, characterized in that one end of the translational member is provided with an opening through which the rotating member passes, and the anti-rotation boss is positioned on the outer wall of the translational member in close proximity to the opening.

3. The brake caliper with reduced volume according to claim 1, characterized in that the translational member is cup-shaped, one end of the translational member is open and the other end is closed, and the cross-section of the translational member is U-shaped.

4. The brake caliper with reduced volume according to any one of claims 1 to 3, characterized in that the cup-shaped bottom and the cup-shaped outer wall of the rotating member and / or the translation member are integrally formed.

5. The brake caliper with reduced volume according to any one of claims 1 to 3, characterized in that the cup-shaped bottom and cup-shaped outer wall of the rotating member and / or the translation member are connected by welding, riveting, or screwing.

6. The brake caliper with reduced volume according to claim 1, characterized in that at least one of the rings is provided.

7. The brake caliper with reduced volume according to claim 1, further comprising a dust cover located between the brake caliper body and the translational member.

8. The brake caliper with reduced volume according to claim 7, characterized in that the ring and the dust cover are covered over the translational member to form a sealing mechanism, and in the axial direction of the cylinder bore, the ring is located between the dust cover and the anti-rotation groove.

9. A brake caliper with reduced volume according to claim 1, characterized in that a position limiting mechanism is provided between the rotating member and the translational member, and the position limiting mechanism is a pair of mutually compatible position limiting bosses.

10. The pair of position limiting bosses that fit together include a first position limiting boss provided at the end of the rotating member away from the actuator, and a second position limiting boss provided in the inner bore of the translational member and close to the closed end of the translational member. The brake caliper with reduced volume according to claim 9, characterized in that the position where the first position limiting boss and the second position limiting boss contact is the zero position of the translational member relative to the rotating member, in which the brake caliper cannot generate braking force.

11. The brake caliper with reduced volume according to claim 1, characterized in that a bearing is installed between the rotating member and the bottom of the cylinder bore.

12. A brake caliper with reduced volume according to claim 11, characterized in that a third ring groove is provided at the end of the rotating member, the third ring groove is located at one end of the rotating member adjacent to the bottom of the cylinder bore, and the bearing is mounted in the third ring groove.

13. The volume-reduced brake caliper according to claim 1, characterized in that the translational member and the rotating member constitute a ball screw, the translational member is used to perform linear motion along the axial direction, the rotating member is used to perform rotational motion, and the translational member and the rotating member are located in the cylinder bore of the brake caliper body.

14. The brake caliper with reduced volume according to claim 13, characterized in that the rotating member is a screw shaft, the translational member is a piston, and the translational member has a screw track on its inner wall, thereby constituting the rotating member and the ball screw.

15. The brake caliper with reduced volume according to claim 1, characterized in that the caliper body has an integrated structure.

16. The brake caliper with reduced volume according to claim 1, characterized in that the axial cross-section of the cylinder bore has a trumpet shape.

17. A volume-reduced brake caliper according to claim 1, further comprising an actuator, an inner pad, a brake disc, and an outer pad, wherein the actuator is used to rotate the rotating member, the inner pad and the outer pad are located on both sides of the brake disc, and the translational member is used to push the inner pad toward the brake disc during braking.

18. The brake caliper with reduced volume according to claim 17, characterized in that the actuator includes at least a motor and a reduction mechanism, and the output shaft of the actuator is directly connected to the rotating member.

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