Wheel brake pin anti-pull-off structure

Abstract

The present invention provides a wheel side brake pin anti-pull-off structure, comprising a pin, a planet carrier and a clamp, wherein the pin comprises an outer cylindrical optical axis and a supporting boss, wherein the supporting boss is provided with a first supporting surface, and a clamping groove is provided on the outer cylindrical optical axis; a pin connecting hole is provided on the planet carrier along the circumferential direction, wherein the upper end of the pin connecting hole is provided with a chamfered surface, and the lower end is provided with a second supporting surface; the cross-sectional diameter of the clamp is d; during assembly, the pin is inserted into the pin connecting hole, so that the first supporting surface abuts against the second supporting surface, and the clamp is clamped and tightly held in the clamping groove, at which time, the distance from the upper end edge of the clamping groove to the chamfered surface is L1>d; during pull-off, the pin and the clamp are simultaneously axially disengaged downward relative to the planet carrier, the first supporting surface is separated from the second supporting surface, and when the clamp abuts against the chamfered surface, the distance from the upper end edge of the clamping groove to the chamfered surface is L2<d. By moving the pin, the distance between the clamping groove and the chamfered surface is changed, so as to prevent the clamp from being disengaged and realize axial limiting.

Description

Technical Field

[0001] The invention relates to the technical field of wheel brakes, and in particular to a wheel brake pin shaft anti-pull-off structure. Background Art

[0002] During the mechanical installation process, many parts need to fit tightly to prevent the connection from falling off or transmitting large torque, so interference fit technology was born. Interference fit is to use the elasticity of the material to expand and deform the hole and put it on the shaft. When the hole is restored, it generates a tightening force on the shaft to connect the two parts.

[0003] At present, the connection method between the planet carrier and the pin shaft in the market is mostly interference fit crimping, but for the mechanism with greater output torque, the existing structure still has many shortcomings, mainly manifested in: 1) The pull-off force is small. If you want to increase the pull-off force, the interference will increase, and the pressing force of the pin shaft will also increase, which requires higher power for the equipment. 2) The increase in interference will easily cause problems such as pressure cracking, hidden cracks, and bending of the parts, resulting in the failure of the pull-off force function. 3) The tolerance of the parts is not easy to control, and the defective rate is high. Summary of the invention

[0004] The technical problem to be solved by the present invention is: in order to overcome the deficiencies in the prior art, the present invention provides a wheel brake pin shaft anti-pull-off structure.

[0005] The technical solution to be adopted by the present invention to solve its technical problems is: a wheel-side brake pin shaft anti-pull-off structure, including a pin shaft, a planetary carrier and a clamp, the pin shaft includes an outer cylindrical optical axis, one end of the outer cylindrical optical axis is provided with a supporting boss, the outer diameter of the supporting boss is larger than the outer diameter of the outer cylindrical optical axis, a first supporting surface is provided on the side of the supporting boss close to the outer cylindrical optical axis, and a clamping groove is provided on the outer cylindrical optical axis; the diameter of the outer cylindrical optical axis is D3, the minimum diameter at the clamping groove is D4, the axial distance from the first supporting surface to the upper end edge of the clamping groove is h1, and the axial distance from the first supporting surface to the lower end edge of the clamping groove is h2;

[0006] A pin connection hole is provided on the planet carrier along the circumferential direction, the axial length of the pin connection hole is h3, an inclined chamfered surface is provided between the upper end of the pin connection hole and the upper end surface of the planet carrier, and a second supporting surface is provided on the planet carrier at the lower end of the pin connection hole;

[0007] The clamp is a circular ring structure with a notch, and the radial cross section is circular; the inner diameter of the clamp is D1, the outer diameter is D2, and the cross-sectional diameter is d;

[0008] The dimensions of the pin and the clamp satisfy: D1<D4<D3<D2, and the dimensions of the shaft pin and the planet carrier satisfy: h2≤h3≤h1;

[0009] During assembly, the pin is inserted into the pin connection hole from bottom to top, so that the first support surface on the pin abuts against the second support surface on the planet carrier, and the clamp is inserted from the pin and clamped and tightly held in the clamping groove. At this time, the distance from the upper edge of the clamping groove to the chamfered surface is L1>d;

[0010] When pulled off, the pin shaft and the clamp simultaneously move out axially downward relative to the planetary carrier, and the first supporting surface on the pin shaft is separated from the second supporting surface on the planetary carrier. When the clamp abuts against the chamfered surface, at this time, the distance from the upper edge of the clamping groove to the chamfered surface is L2<d.

[0011] Specifically, the pin shaft and the pin shaft connecting hole are interference fit.

[0012] Preferably, the interference fit between the pin and the pin connecting hole is 0.003-0.015 mm, within which sufficient axial force can be ensured without causing problems such as compression, hidden cracks, and bending of the planet carrier due to the interference fit.

[0013] Due to the contact position of the clamp, if the chamfered surface is too long, there will be a large range of invalid areas. If the chamfered surface is too short, it cannot meet the pressure generated during abutment. Therefore, the length S of the chamfered surface is: d≤S≤2d, and the inclination angle β is: 45°≤β<90°. The larger the inclination angle, the higher the contact point position during abutment, and the more the pressure generated can press the clamp into the clamping groove, which can prevent the clamp from being squeezed out of the clamping groove.

[0014] Furthermore, it also includes a sun gear, which is connected to the connecting shaft on one side of the planet carrier in one piece or in a separate piece.

[0015] Preferably, the pin shaft, planet carrier and clamp are all made of metal material.

[0016] The beneficial effect of the present invention is that a wheel-side brake pin anti-pull-off structure provided by the present invention realizes the functions of small interference and anti-pull-off (test data is greater than 10000N) by reasonably optimizing the structure of the existing metal pin and planetary carrier, thereby effectively avoiding the problem of metal pin pull-off. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0018] Figure 1 The invention discloses an exploded structural diagram of a wheel brake pin anti-pull-off structure.

[0019] Figure 2 The invention is a schematic diagram of the assembly structure of the wheel brake pin anti-pull-off structure.

[0020] Figure 3 It is a schematic diagram of the structure of the pin shaft.

[0021] Figure 4 It is a schematic diagram of the cross-sectional structure of the pin shaft.

[0022] Figure 5 It is a schematic diagram of the structure of the planet carrier.

[0023] Figure 6 It is a schematic diagram of the structure of the planet carrier.

[0024] Figure 7 It is a schematic diagram of the structure of the clamp.

[0025] Figure 8 It is a top view of the wheel brake pin anti-pull-off structure of the present invention.

[0026] Fig. 9 yes Figure 8 Schematic diagram of the cross-sectional structure of AA.

[0027] Fig.10 yes Fig. 9 Schematic diagram of the enlarged structure at point B in the middle.

[0028] Fig.11 It is a schematic diagram of the anti-pull-off process.

[0029] In the figure: 1, pin shaft, 1-1, outer cylindrical optical axis, 1-2, clamping groove, 1-3, supporting boss, 1-4, first supporting surface, 2, planetary carrier, 2-1, pin shaft connecting hole, 2-2, chamfered surface, 2-3, second supporting surface, 2-4, connecting shaft, 3, sun gear, 4, clamp, 4-1, outer cylindrical surface, 4-2, notch. DETAILED DESCRIPTION

[0030] The present invention will now be described in detail with reference to the accompanying drawings. This figure is a simplified schematic diagram, which only illustrates the basic structure of the present invention in a schematic manner, and therefore only shows the components related to the present invention.

[0031] like Figure 1 and Figure 2 As shown, a wheel brake pin anti-pull-off structure of the present invention includes a pin 1, a planet carrier 2 and a clamp 4. A connecting shaft 2-4 is provided on one side of the planet carrier 2. A sun gear 3 is coaxially provided on the connecting shaft 2-4. The sun gear 3 and the connecting shaft 2-4 can be integrally provided or separately provided. In this embodiment, the sun gear 3 and the connecting shaft 2-4 are integrally processed and formed, and there are three pins 1 and three clamps 4. A stepped shaft hole for connecting an output shaft or an input shaft is also provided on the center shaft on one side of the planet carrier 2. Preferably, the pin 1, the planet carrier 2 and the clamp 4 are all made of metal materials.

[0032] like Figure 3 and Figure 4 As shown, the pin shaft 1 includes an outer cylindrical optical axis 1-1, a supporting boss 1-3 is provided at one end of the outer cylindrical optical axis 1-1, the outer diameter of the supporting boss 1-3 is larger than the outer diameter of the outer cylindrical optical axis 1-1, a first supporting surface 1-4 is provided on the side of the supporting boss 1-3 close to the outer cylindrical optical axis 1-1, and a clamping groove 1-2 is provided on the outer cylindrical optical axis 1-1; the diameter of the outer cylindrical optical axis 1-1 is D3, the minimum diameter at the clamping groove 1-2 is D4, the axial distance from the first supporting surface 1-4 to the upper end edge a of the clamping groove 1-2 is h1, and the axial distance from the first supporting surface 1-4 to the lower end edge b of the clamping groove 1-2 is h2; in this embodiment, the clamping groove 1-2 is an arc shape, and its radius is larger than the cross-sectional diameter d of the clamp 4.

[0033] like Figure 5 and Figure 6 As shown, three pin connection holes 2-1 are provided on the planet carrier 2 along the circumferential direction, the axial length of the pin connection hole 2-1 is h3, an inclined chamfered surface 2-2 is provided between the upper end of the pin connection hole 2-1 and the upper end surface of the planet carrier 2, the length S of the chamfered surface 2-2 is: d≤S≤2d, and the inclination angle β is: 45°≤β<90°; a second supporting surface 2-3 is provided on the planet carrier 2 at the lower end of the pin connection hole 2-1.

[0034] like Figure 7 As shown, the clamp 4 is a circular ring structure with a notch 4-2, and the radial cross section is circular, so the formed shape is an outer cylindrical surface 4-1; the inner diameter of the clamp 4 is D1, the outer diameter is D2, and the cross-sectional diameter is d.

[0035] like Figure 8-Figure 10 As shown, the dimensions of the pin 1 and the clamp 4 satisfy: D1<D4<D3<D2, and the dimensions of the pin and the planet carrier 2 satisfy: h2≤h3≤h1;

[0036] like Fig.11 As shown, the left side figure is a schematic diagram of the positions of various components when assembly is completed, and the right side figure is a schematic diagram of the positions of various components when pull-off occurs.

[0037] During assembly, the pin 1 is inserted into the pin connecting hole 2-1 from bottom to top, and the pin 1 and the pin connecting hole 2-1 have an interference fit, and the interference amount is 0.003-0.015mm; after insertion, the first supporting surface 1-4 on the pin 1 is abutted against the second supporting surface 2-3 on the planetary carrier 2, and the clamp 4 is inserted from the pin 1 and clamped and tightly clamped in the clamping groove 1-2. At this time, the distance from the upper end edge a of the clamping groove 1-2 to the chamfered surface 2-2 is L1>d; due to the interference fit between the pin 1 and the pin connecting hole 2-1, the pin 1 can be fixed in the pin connecting hole 2-1.

[0038] When the axial force on the pin 1 increases and exceeds the bearing capacity of the interference fit, the pin 1 axially disengages from the pin connection hole 2-1 relative to the planetary carrier 2. During the pulling-off process, the pin 1 and the clamp 4 simultaneously disengage axially downward relative to the planetary carrier 2, and the first support surface 1-4 on the pin 1 is separated from the second support surface 2-3 on the planetary carrier 2. When the clamp 4 abuts against the chamfered surface 2-2 (i.e., the clamp 4 is tangent to the chamfered surface 2-2), at this time, the distance from the upper end edge a of the clamping groove 1-2 to the chamfered surface 2-2 is L2<d, thereby preventing the clamp 4 from being forced to disengage from the opening between the clamping groove 1-2 and the chamfered surface 2-2. The freedom of the pin 1 is constrained to achieve axial locking and radial coaxial positioning.

[0039] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the scope of the present invention through the above description. The technical scope of this invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A wheel brake pin anti-pull-off structure, characterized in that: It includes a pin shaft, a planet carrier and a clamp, the pin shaft includes an outer cylindrical optical axis, one end of the outer cylindrical optical axis is provided with a supporting boss, the outer diameter of the supporting boss is larger than the outer diameter of the outer cylindrical optical axis, a first supporting surface is provided on the side of the supporting boss close to the outer cylindrical optical axis, and a clamping groove is provided on the outer cylindrical optical axis; the diameter of the outer cylindrical optical axis is D3, the minimum diameter at the clamping groove is D4, the axial distance from the first supporting surface to the upper end edge of the clamping groove is h1, and the axial distance from the first supporting surface to the lower end edge of the clamping groove is h2; A pin connection hole is provided on the planet carrier along the circumferential direction, the axial length of the pin connection hole is h3, an inclined chamfered surface is provided between the upper end of the pin connection hole and the upper end surface of the planet carrier, and a second supporting surface is provided on the planet carrier at the lower end of the pin connection hole; The clamp is a circular ring structure with a notch, and the radial cross section is circular; the inner diameter of the clamp is D1, the outer diameter is D2, and the cross-sectional diameter is d; The dimensions of the pin and the clamp satisfy: D1<D4<D3<D2, and the dimensions of the pin and the planet carrier satisfy: h2≤h3≤h1; During assembly, the pin is inserted into the pin connection hole from bottom to top, so that the first support surface on the pin abuts against the second support surface on the planet carrier, and the clamp is inserted from the pin and clamped and tightly held in the clamping groove. At this time, the distance from the upper edge of the clamping groove to the chamfered surface is L1>d; When pulled off, the pin shaft and the clamp simultaneously move out axially downward relative to the planetary carrier, and the first supporting surface on the pin shaft is separated from the second supporting surface on the planetary carrier. When the clamp abuts against the chamfered surface, at this time, the distance from the upper edge of the clamping groove to the chamfered surface is L2<d.

2. The wheel brake pin anti-pull-off structure according to claim 1, characterized in that: The pin shaft and the pin shaft connecting hole are interference fit.

3. The wheel brake pin anti-pull-off structure according to claim 2, characterized in that: The interference fit between the pin and the pin connecting hole is 0.003-0.015mm.

4. The wheel brake pin anti-pull-off structure according to claim 1, characterized in that: The length S of the chamfered surface is: d≤S≤2d, and the inclination angle β is: 45°≤β<90°.

5. The wheel brake pin anti-pull-off structure according to claim 1, characterized in that: It also includes a sun gear, which is connected to the connecting shaft on one side of the planet carrier in one piece or in parts.

6. The wheel brake pin anti-pull-off structure according to claim 1, characterized in that: The pin shaft, the planet carrier and the clamp are all made of metal materials.

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