Hub unit having a brake disc

Abstract

A hub unit has a brake disc and a hub body disposed to rotate with a rim on which a tire is mounted. An internal space is formed in the hub body, wherein the brake disc is fixed in the internal space. A fixed shaft is disposed and fixed along a rotation center shaft of the hub body. A brake shoe is coupled to the fixed shaft. A brake pad is disposed to contact the brake disc. A braking force applier supplies a braking force to the hub body wherein the brake pad and the brake disc are in contact with each other.

Claims

1. A hub unit having two brake discs, the hub unit comprising: a hub body, wherein an internal space is formed in the hub body and the two brake discs are fixed in the internal space; a fixed shaft disposed and fixed along a rotation center shaft of the hub body; a pair of brake shoes that face each other and that are coupled to the fixed shaft, wherein two brake pads are carried on the pair of brake shoes and come in contact with the two brake discs; and a braking force applier for supplying a braking force to the pair of brake shoes, wherein the two brake pads and the two brake discs are in contact with each other, wherein the braking force applier includes i) a piston member disposed to push the pair of brake shoes such that the two brake pads contact the two brake discs, and ii) an elastic member disposed to supply elastic force in a direction in which the two brake pads are separated from the two brake discs, wherein each of the two brake pads is disposed at an external side of a respective one of the two brake shoes, wherein each of the two brake discs is disposed at an inner side of the hub body corresponding to a respective one of the two brake pads, wherein the elastic member is disposed in or on the fixed shaft and supplies the elastic force to an external side of the pair of brake shoes to push the pair of brake shoes toward each other, and wherein the piston member is disposed between the pair of brake shoes and pushes the pair of brake shoes away from each other.

2. The hub unit of claim 1, wherein the two brake pads are fixed in surfaces of the pair of brake shoes that face each other, and the two brake discs are fixed to an interior circumference of the hub body with a predetermined gap between the two brake discs and the two brake pads.

3. The hub unit of claim 2, wherein the two brake discs are disposed between the pair of brake shoes.

4. The hub unit of claim 2, wherein the elastic member is disposed between the pair of brake shoes and pushes the pair of brake shoes away from each other.

5. The hub unit of claim 2, wherein the piston member is disposed at an exterior side of the pair of brake shoes, respectively, and pushes the pair of brake shoes toward each other.

6. The hub unit of claim 1, wherein the fixed shaft is disposed to penetrate a center portion of the pair of brake shoes, and the two brake pads are disposed respectively, in the pair of brake shoes.

7. The hub unit of claim 6, wherein the fixed shaft is engaged with the center portion of the pair of brake shoes to fix the pair of brake shoes to the fixed shaft.

8. The hub unit of claim 1, wherein the hub body is rotatably disposed relative to the fixed shaft through a bearing.

9. The hub unit of claim 1, wherein the two brake discs are fixed to an inner side of the hub body and are disposed to face the two brake pads with a predetermined gap therebetween.

10. The hub unit of claim 1, wherein a body expansion portion is formed as a part of the hub body such that an exterior diameter of the body expansion portion is expanded in a radial direction, and the two brake discs are fixed to an inner side of the body expansion portion.

11. The hub unit of claim 1, further comprising: a brake cable for supplying hydraulic pressure to the piston member.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic cross-sectional view of a hub unit having a brake disc related to the present disclosure.

(2) FIG. 2 is a schematic cross-sectional view of a hub unit having a brake disc according to an embodiment of the present disclosure.

(3) FIG. 3 is a schematic cross-sectional view of a hub unit having a brake disc according to another embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(4) Hereinafter, embodiments of the present disclosure are described in detail with reference to the accompanying drawings.

(5) In the drawings, size and thickness of each element is only approximately shown for better understanding and ease of description. Therefore, the present disclosure is not limited to the drawings, and the thicknesses of layers, films, panels, regions, and the like, are exaggerated for clarity.

(6) However, the drawings and description are to be regarded as illustrative in nature and not restrictive. Like reference numerals designate like elements throughout the specification.

(7) The terms first, second, third, and the like in the following description are for distinguishing the components or configurations where the names of such components or configurations are the same. The present disclosure is not limited to the order.

(8) Hereinafter, a hub unit having a brake disc according to an embodiment of the present disclosure is described in detail with reference to accompanying drawings.

(9) FIG. 2 is a schematic cross-sectional view of a hub unit having a brake disc according to an embodiment of the present disclosure.

(10) Referring to FIG. 2, the hub unit includes a brake cable 210, a quick release (QR) lever 205, a first bearing 110 at one end of the hub unit, a hub body 115, a fixed shaft 100, a second bearing 110 at the other end of the hub unit, a QR element or rod 200 coupled to the QR lever 205, a brake shoe 260, a brake pad 120, a brake disc 215, a body expansion portion 125, a piston member 255, and an elastic member 250.

(11) The brake shoe 260 is formed as a pair of the brake shoes, each having a disc shape, and wherein the pair of brake shoes are spaced apart and face each other. The fixed shaft 100 is disposed to penetrate a center portion of the brake shoe 260. The brake shoe 260 is fixed to the fixed shaft 100 in a rotation direction and is also movable along the fixed shaft in an axial direction. In this embodiment, the brake disc 215 is also formed as a pair of the brake discs, each adjacent one of the brake shoes 260.

(12) The piston member 255 is interposed between the pair of the brake shoes 260. The piston member 255 pushes the brake shoes 260 outwardly in an axial direction, away from one another in this embodiment, by using hydraulic pressure transferred through the brake cable 210.

(13) The elastic member 250 is disposed on an external or outward facing side of each of the brake shoes 260 and is based on the outer surface of the fixed shaft 100. The elastic member 250 supplies elastic force in a direction, opposite to the pushing direction of the piston, in which the brake pad 120 is separated from the brake disc or discs 215.

(14) The body expansion portion 125 is a part of the hub body 215 in which an exterior diameter of the hub body is expanded in a radial direction. The body expansion portion 125 is formed in a center portion of the hub body 115 in a length or axial direction thereof. The brake discs 215 are each disposed on or adjacent an inner side or axial inward facing side of the body expansion portion 125 adjacent each brake shoe 260 in this embodiment.

(15) The brake discs 215 face the brake shoes 260 respectively and each of the brake shoes carries a brake pad 120. The brake pads 120 are disposed on the outward facing sides of the respective brake shoes 260 and thus correspond to the brake discs 215 so as to be capable of contacting the brake discs.

(16) The elastic member 250 is disposed in a space formed in a center portion of the fixed shaft 100 in a length or axial direction thereof. An interior circumference of each of the brake shoes 260 is slidably disposed in a groove formed in the fixed shaft 100. The groove may also be the space, in which the elastic member 250 is disposed. The piston member 255 may be disposed in a position that corresponds to the elastic member 250. In other words, the piston member 255 and elastic member 250 may be positioned on the same axis, i.e., at the same radius about the fixes shaft 100. Also, there may be two of the elastic members 250, one adjacent each of the brake shoes 260 in this embodiment.

(17) When a rider operates a brake handle (not shown), hydraulic pressure is transferred through the brake cable 210, whereby the piston member 255 pushes the brake shoe 260s outwardly away from one another in a length or axial direction.

(18) The brake pads 120, which are fixed to the external or outward facing sides and near the external periphery of the brake shoes 260, come in contact with the respective brake discs 215. Frictional force is thereby generated between the brake pads and the brake discs.

(19) The bearings 110 are interposed between the interior circumference of the hub body 115 and the exterior circumference of the fixed shaft 100. The QR element or rod 200 is inserted and disposed along a center axis of the fixed shaft 100 in the length or axial direction.

(20) When the QR lever 205 is locked, the fixed shaft 100 is fixed to a drop-out of a frame through the QR element or rod 200. The hub body 115 can be rotatable on and relative to the fixed shaft 100 through the bearings 110.

(21) An exterior circumference of the hub body 115 is connected with a rim (not shown) through a spoke (not shown), and a tire is mounted on the rim. Herein, structures of the hub body 115, the spoke, the rim, and the tire are well known to those having ordinary skill in the art, and thus a detailed description will be omitted.

(22) FIG. 3 is a schematic cross-sectional view of a hub unit having a brake disc according to another embodiment of the present disclosure.

(23) Referring to FIG. 3, the hub unit includes a brake cable 210, a QR lever 205, a first bearing 110, a hub body 115, a fixed shaft 100, a QR element or rod 200, a brake shoe 260, a brake pad 120, a brake disc 215, a body expansion portion 125, piston members 255, a second bearing 110, and an elastic member 250.

(24) The brake shoe 260 in this embodiment is again formed as a pair of the brake shoes, each having a disc shape, and each facing the other. The fixed shaft 100 is disposed to penetrate a center portion of the brake shoes 260. The brake shoes 260 are fixed to the fixed shaft 100 in a rotation direction and are movable therealong in an axial direction.

(25) The elastic member 250 is interposed between the brake shoes 260. The elastic member 250 supplies elastic force in an axial direction in which the brake pad 120 is separated from the brake disc 215. In this embodiment, the elastic member 250 pushes the brake shoes axially outward away from each other.

(26) The piston members 255 push the brake shoes 260 toward one another to a center portion of the fixed shaft 100 in an axial direction. The elastic member 250 and the piston members 255 may again be disposed along the same axis corresponding to one another.

(27) The body expansion portion 125, in which an exterior diameter of the hub body 115 is expanded in a radial direction, is formed at a center portion of the hub body 115 in a length or axial direction thereof. The brake disc 215 is disposed between the pair of brake shoes 260 in an internal space of the body expansion portion 125. An end or periphery portion of the brake disc 215 is fixed to an interior circumferential surface of the body expansion portion 125.

(28) Accordingly, the hub body 115, the body expansion portion 125, and the brake disc 215 are rotatable together along with a rim and wheel. The brake pads 120 are mounted on an inner or inward facing side of the corresponding brake shoes 260 and face the brake disc 215.

(29) The piston member 255 is disposed in a space formed in a center portion of the fixed shaft 100 in a length or axial direction thereof. An interior circumference of each of the brake shoes 260 is slidably disposed in a groove, which may be the space, formed in the fixed shaft 100.

(30) When a rider operates a brake handle, hydraulic pressure is transferred through the brake cable 210, and the piston members 255 push the brake shoes 260 inwardly toward brake disc 215 in a length or axial direction.

(31) The brake pads 120, which are fixed neat the external or radial periphery and to the internal or inward facing sides of the brake shoes 260, come in contact with the brake disc 215. Frictional force is thereby generated between the brake pads and the brake disc.

(32) As described above, according to an embodiment of the present disclosure, the brake disc 215 is, or the brake discs 215, are disposed within in the hub body 115 and disposed at a center portion of the fixed shaft 100 in a length or axial direction. Thus, it is possible to prevent the brake disc or discs from being bent because the brake disc or discs are not exposed. Further, because the brake disc or discs are not exposed, the brake disc or discs are prevented from causing injury to a person. Further, instability of steering can be prevented by removing moment generated in one direction during braking because the brake disc or discs are center-mounted within the hub unit.

(33) While this disclosure has been described in connection with what is presently considered to be practical embodiments, it is to be understood that the disclosure is not limited to the disclosed embodiments. On the contrary, this disclosure s intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.