brake

Abstract

This invention relates to a brake, comprising a piston cylinder and a lead screw mechanism. The lead screw mechanism is disposed within the piston cylinder and includes a lead screw and a nut. The piston cylinder has an inner wall, and an annular abutment mechanism is fixed to the inner wall behind the nut. The abutment mechanism has a flange protruding from the inner wall. When the nut retracts, it abuts against the flange and drives the piston cylinder to retract together. The brake structure of this invention effectively reduces drag and makes brake control more sensitive.

Description

Technical Field

[0001] This invention relates to brakes. Background Technology

[0002] In existing technology, a "dragging" problem occurs when the brake pads retract. That is, when the lead screw mechanism drives the piston rod and friction pads to retract, the piston only begins to retract after the lead screw nut has retracted a certain distance. This dragging phenomenon causes the friction pads to remain on the brake disc for a longer period, undoubtedly increasing the vehicle's energy consumption.

[0003] Chinese patent document CN 220581562 U discloses a brake, which includes a transmission structure for driving a piston using a lead screw and nut. The lead screw and nut comprise a lead screw and a nut. The lead screw is rotatably mounted on a housing. The lead screw and nut are threaded together. When the lead screw rotates, it drives the nut to move axially. The lead screw and nut drive the piston to move axially. An elastic ring is provided at the front end of the piston and its outer cylinder. During braking, the piston translates outward, stretching the elastic ring and causing it to deform. When the brake is released, the nut is first retracted by the reverse rotation of the motor, moving away from the piston. The elastic ring then pulls the piston backward through its elastic force. However, during this process, the piston sometimes fails to return to its original position in time, resulting in a dragging phenomenon. Summary of the Invention

[0004] The main objective of this invention is to provide a brake structure with low drag.

[0005] To achieve the above objectives, the present invention provides a brake, comprising a piston cylinder and a lead screw mechanism, wherein the lead screw mechanism is disposed within the piston cylinder, and the lead screw mechanism comprises a lead screw and a nut, characterized in that:

[0006] The piston cylinder has an inner wall, and an annular abutment mechanism is fixed behind the nut on the inner wall. The abutment mechanism has a flange protruding from the inner wall. When the nut retracts, it abuts against the flange and drives the piston cylinder to retract together.

[0007] In some embodiments of the present invention, a mounting groove is arranged circumferentially at the rear of the inner wall of the cylinder, and the abutment mechanism is engaged in the mounting groove.

[0008] In some embodiments of the present invention, the abutment mechanism comprises: stacked along the axial direction:

[0009] The rigid first annular member, and

[0010] The elastic second ring member,

[0011] The second annular component is located on the side closest to the nut.

[0012] In some embodiments of the present invention, the mounting groove has a first mounting groove portion for engaging a first annular member and a second mounting groove portion for engaging a second annular member along the axial direction.

[0013] In some embodiments of the present invention, the inner edge of the second annular member protrudes beyond the inner wall of the cylinder.

[0014] In some embodiments of the present invention, the first annular component is a retaining ring.

[0015] In some embodiments of the present invention, the second annular component is a rectangular sealing ring.

[0016] In some embodiments of the present invention, the rear end of the nut has an abutment surface along the circumferential direction, and the nut abuts against the abutment mechanism through the abutment surface.

[0017] The brake structure of the present invention can effectively reduce drag and make brake control more sensitive. Attached Figure Description

[0018] Figure 1 The existing technology CN220581562U Figure 2 .

[0019] Figure 2 This is a cross-sectional schematic diagram of the piston and lead screw mechanism.

[0020] Figure 3 This is an exploded view of the piston and lead screw mechanism.

[0021] Figure 2 and Figure 3 The marker in:

[0022] 5-Lead screw mechanism, 51-Nut, 511-Abutting surface, 52-Lead screw, 521-Spline structure.

[0023] 8-Piston cylinder, 81-Mounting groove, 811-Second mounting groove, 812-First mounting groove, 82-Inner wall of cylinder, 821-Abutting part, 83-Elastic ring mounting groove, 84-Front end portion,

[0024] 9-Abutment mechanism, 91-Rectangular sealing ring, 92-Snap ring.

[0025] Figure 1 Markings in (Prior Art):

[0026] 100-Brake, 120-Motor, 130-Transmission device, 151-Lead screw, 152-Nut, 153-Threaded mating part, 154-Connecting part, 155-Transition step, 156-Snap ring, 160-Housing, 161-Force sensor, 163-Anti-rotation washer, 166-Thrust platform, 167-Thrust bearing, 170-Bracket, 181-Inner friction plate, 182-Outer friction plate, 183-Piston, 190-Cage, 194-First through hole. Detailed Implementation

[0027] For ease of description, this article uses "forward" and "backward" to represent the two relative directions of the screw mechanism's movement. "Forward" indicates the direction in which the screw moves closer to the brake disc, while "backward" indicates the direction in which the screw moves closer to the brake disc.

[0028] In existing relevant examples, patent publication CN220581562U discloses a specific structure of a brake driven by a lead screw mechanism. (Reference) Figure 1 The cross-sectional structure is shown in the image. The piston 183, which can slide relative to the cylinder, is visible in the center of the image. The piston has a cylindrical structure, and the cylinder is formed inside the housing 160. The lead screw mechanism (lead screw nut) is located inside the cylindrical piston 183. The lead screw nut includes a lead screw 151 and a nut 152. The lead screw 151 is rotatably mounted on the housing 160. The lead screw 151 and the nut 152 are threaded together. When the lead screw 151 rotates, it drives the nut 152 to move axially. The piston 183 is an overall cylindrical structure with a closed front end and an open rear end. Its front end has a front portion for connecting with the internal friction plate. The interior has a circumferentially arranged inner wall, and the front part of the inner wall also has an abutment portion that abuts against the front end of the nut. During braking, the nut moves forward, driving the piston sleeve forward through the abutment portion, and further driving the internal friction plate closer to the brake disc. Figure 1 The state in the middle is the state after the brake is released. It can be foreseen that, since the rear part of its piston inner wall is an open mechanism, when the nut moves forward to push the piston out of the cylinder to complete the braking and needs to be released again, due to the open structure, the nut can move back freely relative to the piston, thus failing to structurally prevent dragging from occurring.

[0029] In view of the aforementioned problems in the prior art, the present invention improves the piston cylinder structure by fixing an annular abutment mechanism to the inner wall of the piston cylinder behind the nut. When the nut retracts, it abuts against the abutment mechanism and drives the piston cylinder to retract together. Thus, when the brake is released, the piston cylinder can be directly pushed by the nut. This thrust helps the piston cylinder to retract promptly when the brake is released, thereby reducing or avoiding dragging problems and reducing energy consumption.

[0030] The aforementioned abutment mechanism can be fixed to the inner wall of the cylinder in a non-removable manner, or it can be fixed to the inner wall of the cylinder in a detachable manner. The lead screw nut can be assembled into the piston cylinder first and then fixed. When fixing first, the annular abutment mechanism needs to have a certain elastic deformation capability. The lead screw nut can be installed into the piston cylinder by pushing it in, with the help of the elastic deformation of the abutment mechanism.

[0031] In one example of detachable fixing, see [reference]. Figure 2 A mounting groove 81 is arranged circumferentially on the rear part of the inner wall 82 of the piston cylinder 8, and an annular abutment mechanism 9 is engaged in the mounting groove 81. This mounting method has the advantages of simple structure and easy operation. The mounting groove can be formed directly during the manufacturing of the piston cylinder, or it can be made by machining a pre-manufactured piston cylinder. During assembly, it is only necessary to assemble the lead screw mechanism 5 into the piston cylinder 8 and then place it into the annular mounting groove 81.

[0032] One specific structure of the abutment mechanism includes a rigid first annular member stacked axially and a resilient second annular member, wherein the second annular member is disposed on the side near the nut. The rigid first annular member provides the main rigidity of the abutment mechanism, ensuring that when the nut retracts, the thrust can drive the piston cylinder to move via the abutment mechanism. The resilient second annular member is used to abut against the nut, cushioning the impact of the nut through its elasticity to prevent the piston cylinder from being impacted and vibrating. In some embodiments, the mounting groove is further divided axially into a first mounting groove portion for engaging the first annular member and a second mounting groove portion for engaging the second annular member. (Reference) Figure 2 and Figure 3 The first annular component is a snap ring 92, the second annular component is a rectangular sealing ring 91 with a rectangular cross-section, and the mounting groove 81 is divided into a first mounting groove portion 812 and a second mounting groove portion 811.

[0033] In one specific structure of the nut, a contact surface may optionally be present circumferentially at the rear end, and contact is achieved by the contact surface fitting with the shape of the contact mechanism. For example... Figure 2 In the middle, the nut 51 fits with the inner ring contour of the rectangular sealing ring 91 through the abutment surface 511, thereby better realizing the abutment between the nut and the abutment mechanism.

[0034] Furthermore, the piston cylinder and lead screw mechanism of the present invention may include other existing structures, see reference. Figure 2 and Figure 3It includes, but is not limited to: an elastic ring mounting groove 83 for mounting an elastic ring is provided circumferentially at the front part of the outer wall of the piston cylinder; the front end of the piston cylinder has a front end portion 84 for connecting with the inner friction plate; the front part of the inner wall 82 of the cylinder also has an abutment portion 821 for abutting with the front end of the nut; and a spline structure 521 for connecting with the drive shaft is provided at the rear end of the lead screw.

[0035] The aforementioned piston cylinder and lead screw assembly can be fitted into the piston cylinder of any existing brake housing. The rear end of the lead screw is connected to the drive shaft, and the front end of the piston sleeve is connected to the inner friction plate, and they slide relative to each other within the piston cylinder. When it is necessary to move the inner friction plate backward to engage the brake, the nut 51 first abuts against the rectangular sealing ring 811, thereby causing the piston cylinder 8 to begin to move backward. This process reduces or avoids dragging, reduces energy consumption, and has beneficial technical effects.

[0036] The embodiments described in this invention are for illustrative purposes only and do not constitute a limitation on the scope of the claims. Other substantially equivalent substitutions that can be conceived by those skilled in the art are all within the scope of protection of this invention.

Claims

1. A brake, comprising a piston cylinder and a lead screw mechanism, wherein the lead screw mechanism is disposed within the piston cylinder, and the lead screw mechanism comprises a lead screw and a nut, characterized in that: The piston cylinder has an inner wall, and an annular abutment mechanism is fixed behind the nut on the inner wall. The abutment mechanism has a flange protruding from the inner wall. When the nut retracts, it abuts against the flange and drives the piston cylinder to retract together.

2. The brake as claimed in claim 1, characterized in that: A mounting groove is arranged circumferentially on the rear part of the inner wall of the cylinder, and the abutment mechanism is engaged in the mounting groove.

3. The brake as described in claim 2, characterized in that... The abutment mechanism comprises: stacked along the axial direction: The rigid first annular member, and The elastic second ring member, The second annular component is located on the side closest to the nut.

4. The brake as described in claim 3, characterized in that... The mounting groove has a first mounting groove portion for engaging the first annular member and a second mounting groove portion for engaging the second annular member along the axial direction.

5. The brake as described in claim 3, characterized in that... The inner edge of the second annular component protrudes from the inner wall of the cylinder.

6. The brake as described in claim 3, characterized in that... The first annular component is a retaining ring.

7. The brake as claimed in claim 3, characterized in that... The second annular component is a rectangular sealing ring.

8. The brake as claimed in claim 1, characterized in that... The nut has a contact surface along its rear end in the circumferential direction, and the nut abuts against the contact mechanism through the contact surface.

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