Bushing with axial and radial tolerance compensation

Abstract

The utility model discloses a bushing with axial and radial tolerance compensation, which comprises a bushing tube and an axial compensation base, the bushing tube and the axial compensation base which are coaxially arranged are of an integral structure, the inner circle surface of the bushing tube is wave-shaped, the outer circle surface of the bushing tube is a convex-concave surface, and the outer circle surface of the bushing tube is a concave-convex surface. The groove bottoms of the grooves in the outer circle surface of the bushing cylinder correspond to the wave crests on the inner circle surface in position; the bushing designed by the utility model is used for solving the problems of rotation clamping stagnation or abnormal sound and the like caused by dimensional deviation of the current shaft tube and the central shaft, and meanwhile, the running reliability of the brake pedal is improved by optimizing the structure of the bushing, storing lubricating grease and prolonging the lubricating time.

Description

Technical Field

[0001] The utility model belongs to the field of automobile brake pedal parts, in particular to a bushing for axial and radial tolerance compensation. Background Art

[0002] The working principle of the automobile brake pedal can be simplified as follows: the driver steps on the brake pedal, the pedal arm rotates around the central axis, directly pushing the booster push rod to achieve the transmission of pedal force and then brake; due to the reliability requirements for the pedal and the mechanism, the main structural materials of the hinge of the pedal and the central axis are all made of metal. As a component that works frequently during the use of the vehicle, the collision and wear between metal and metal are inevitable. Collision and wear will cause abnormal noise and loss of transmission efficiency. Therefore, the rotation of the pedal arm generally adopts the hinge method of central axis + bushing + shaft tube, and the movement of the central axis is supported and guided by a plastic bushing with high strength and low friction coefficient to reduce abnormal wear and friction.

[0003] The traditional bushing is composed of an axial compensation base + a bushing sleeve. The bushing sleeve of this type of bushing is generally a straight-face structure, so the bushing does not have a compensation function. If the shaft tube diameter on the pedal arm is too small (shaft tube welding causes deformation) or the center shaft diameter is too large, it will cause increased rotation resistance and even rotation jamming; if the shaft tube on the pedal arm is too short, it will cause increased axial clearance, resulting in axial shaking and abnormal noise. Summary of the invention

[0004] The utility model provides a bushing for axial and radial tolerance compensation, aiming at solving the technical problem that the existing bushing has no axial and radial compensation function.

[0005] In order to solve the above technical problems, the technical solution of the utility model is: a bushing for axial radial tolerance compensation, comprising a bushing and an axial compensation base, the coaxially arranged bushing and the axial compensation base are an integral structure, characterized in that: the inner circular surface of the bushing is wavy, the outer circular surface of the bushing is convex and concave, and the bottom of the groove on the outer circular surface of the bushing corresponds to the position of the wavy wave peak on the inner circular surface.

[0006] The above technical solution is further limited to that the wave shape is composed of continuous staggered The cross sections of the wave crests and wave troughs are both arc-shaped.

[0007] The above technical solution is further limited in that the diameter of the trough in the wave shape is 0.1-0.2 mm smaller than the outer diameter of the central axis, and the diameter of the peak in the wave shape is 0.1-0.2 mm larger than the outer diameter of the central axis.

[0008] The above technical solution is further limited in that the convex and concave surfaces are composed of strip-shaped grooves distributed at intervals in the circumferential direction, and the length direction of the grooves is consistent with the axial direction of the bushing.

[0009] The above technical solution is further limited in that the cross-section of the alveolar is V-shaped.

[0010] The above technical solution is further limited in that the axial compensation base is a curved flange structure, and a plurality of first notches are evenly formed on the outer edge of the flange structure.

[0011] Beneficial effects: 1. Axial and radial tolerance compensation, low requirements for connector processing, and reduced manufacturing costs: through the corrugation on the inner surface of the bushing and the tooth structure on the outer surface, it will expand and deform appropriately according to the actual installed shaft tube inner diameter and the center shaft outer diameter, so as to perform radial compensation; the axial compensation base will also perform axial tolerance compensation after the bolts are tightened; this reduces the processing accuracy requirements for the shaft tube and the center shaft, and reduces manufacturing costs; 2. Effectively retain grease:

[0012] The wavy inner wall structure on the bushing can reduce the contact area between the bushing and the center shaft, reduce friction, and ease surface stress. At the same time, the trough position of the inner circular surface of the bushing can effectively accumulate grease, avoiding pollution caused by grease diffusion and overflow, effectively extending the lubrication time, and thus maintaining the cleanliness and reliability of the shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural diagram of the utility model.

[0014] Figure 2 yes Figure 1 Stereoscopic diagram.

[0015] Figure 3 yes Figure 1 Top view of the .

[0016] Figure 4 This is the use state of the utility model. DETAILED DESCRIPTION

[0017] like Figure 1 , Figure 2 and Figure 3As shown, a bushing for axial radial tolerance compensation includes a bushing 1 and an axial compensation base 2. The bushing and the axial compensation base are coaxially arranged and are an integral structure. The inner circular surface of the bushing is a wave shape 101, and the outer circular surface of the bushing is a convex and concave surface 102. The bottom of the groove on the outer circular surface of the bushing corresponds to the position of the wave crest on the inner circular surface; the bottom of the groove corresponds to the position of the wave crest, so that the deformation of the inner circle and the outer circle of the bushing is compensated for each other; that is, when the outer diameter and inner diameter of the central shaft are too large, the crest surface on the inner circle of the bushing is deformed outward, and this deformation will offset the bottom end of the V-shaped tooth groove on the outer circle, so as to ensure uniform deformation of the bushing and avoid stress concentration caused by accumulated deformation of the bushing, thereby causing destructive deformation;

[0018] The material of the bushing and the axial compensation base is a polymer material with ductility and ductility strength, such as POM, Pa6, etc.;

[0019] like Figure 1 , Figure 2 and Figure 3 As shown, the wave shape 101 is composed of continuous staggered The wave crest 1011 and the wave trough 1012 are formed, and the cross sections of the wave crest and the wave trough are both arc-shaped;

[0020] like Figure 1 , Figure 2 and Figure 3 As shown, the diameter of the trough 1012 in the wave shape 101 is 0.1-0.2mm smaller than the outer diameter of the central shaft, and the diameter of the wave crest in the wave shape is 0.1-0.2mm larger than the outer diameter of the central shaft; Advantages: the diameter of the trough is 0.1-0.2mm smaller than the outer diameter of the central shaft, and the diameter of the wave crest in the wave shape is 0.1-0.2mm larger than the outer diameter of the central shaft, which can ensure that when the inner circle of the bushing and the central shaft are matched, the bushing will deform first, and the wave crests and troughs will fit the outer wall of the central shaft as much as possible, increase the contact area with the central shaft, and evenly share the pressure, thereby improving the rotation stability of the brake pedal;

[0021] like Figure 1 , Figure 2 and Figure 3 As shown, the convex-concave surface 102 is composed of strip-shaped grooves 1021 distributed at intervals in the circumferential direction, and the length direction of the grooves is consistent with the axial direction of the bushing;

[0022] like Figure 1 , Figure 2 and Figure 3As shown, the cross section of the tooth groove 1021 is V-shaped; Advantages: The V-shaped groove is mainly used to reserve compensation space for the inner circular deformation of the bushing sleeve. Secondly, due to the matching of the outer circle of the bushing and the welded shaft tube, the surface of the welded shaft tube is electrophoretic painted, and there may be defects such as pitting in batches. As the pedal is scraped off during normal operation, the V-shaped groove has good self-cleaning ability, which can collect the fallen paint stains and avoid the pedal from getting stuck;

[0023] like Figure 1 , Figure 2 and Figure 3 As shown, the axial compensation base 2 is a curved flange structure, and a plurality of first notches 201 are evenly formed on the outer edge of the flange structure.

[0024] like Figure 4 As shown in the figure, the application of bushings on automobile brake pedals: automobile brake pedals are mainly composed of bracket 3, pedal arm 4, shaft tube 5, and center shaft 6, wherein one end of the pedal arm is fixedly connected to the shaft tube, and the center shaft is a bolt and nut assembly. The bushing sleeve of the bushing is assembled in the shaft tube end of the pedal arm, and the center shaft passes through the bracket and the inner circle of the bushing sleeve and is locked with bolts; when the inner diameter of the shaft tube becomes smaller due to welding deformation or the outer diameter of the center shaft is larger, the radial clearance becomes smaller, and the surface wave peak of the bushing sleeve is squeezed inward, so that the shaft tube and the bushing fit evenly, avoiding the problem of rotation jam; when the inner diameter of the shaft tube becomes larger due to welding deformation or the outer diameter of the center shaft is smaller, the radial clearance becomes larger, and the surface wave valley of the bushing sleeve is squeezed outward, so that the shaft tube and the bushing fit evenly, avoiding the problem of rotation looseness; at the same time, when the bolts are locked, an axial pressing force is generated on the bushings at both ends, and the axial compensation base on the bushing will be deformed, eliminating the axial clearance, and avoiding the shaking and abnormal noise caused by the axial clearance.

Claims

1. A bushing for axial radial tolerance compensation, comprising a bushing sleeve and an axial compensation base, wherein the bushing sleeve and the axial compensation base are coaxially arranged and are an integral structure, and are characterized in that: The inner circular surface of the bushing is wavy, the outer circular surface of the bushing is convex and concave, and the bottom of the groove on the outer circular surface of the bushing corresponds to the position of the wave crest on the inner circular surface.

2. The bushing for axial and radial tolerance compensation according to claim 1, characterized in that: The wave shape consists of continuous staggered The cross sections of the wave crests and wave troughs are both arc-shaped.

3. A bushing for axial and radial tolerance compensation according to claim 1 or 2, characterized in that: The convex and concave surfaces are composed of strip-shaped grooves distributed at intervals in the circumferential direction, and the length direction of the grooves is consistent with the axial direction of the bushing.

4. The bushing for axial and radial tolerance compensation according to claim 3 is characterized in that: The axial compensation base is a curved flange structure, and a plurality of first notches are evenly formed on the outer edge of the flange structure.

5. A bushing for axial and radial tolerance compensation according to claim 1, 2 or 4, characterized in that: The diameter of the trough in the wave shape is 0.1-0.2 mm smaller than the outer diameter of the central axis, and the diameter of the peak in the wave shape is 0.1-0.2 mm larger than the outer diameter of the central axis.

6. The bushing for axial and radial tolerance compensation according to claim 3, characterized in that: The cross section of the alveolar cavity is V-shaped.

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