JP2006321420A - Wire spoke wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate a cause damaging a large number of wire spokes used for a spoke wheel and to reduce the weight of a wheel by reducing required strength. <P>SOLUTION: A fitting part inserted to a spoke hole and a male screw thread-engaged with a nipple are provided on a wire spoke and a radial gap is interposed between an outer periphery of the fitting part and an inner surface of the spoke hole. A bent part for directing the male screw in a direction of the nipple is provided on the fitting part and a bending angle of the bent part is set larger than an angle at completion of assembling. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wire spoke wheel suitable for a wheel of a motorcycle or a sports car, and more particularly to a connection structure for connecting a wire spoke and a spoke hole of a light alloy hub.

  In general, as shown in FIG. 1, a wire spoke wheel is connected between a rim 10 for fitting a tire and a hub 20 made by casting an aluminum alloy by a wire spoke 12 made of steel wire. That is, one end of the wire spoke 12 is engaged with a spoke hole 24 provided in the hub, and the other end is screwed into a nipple 14 locked to the rim 10, and the nipple 14 is operated so that the wire spoke 12 is engaged. It is configured to be pulled and tightened toward the rim 10 side.

  The spoke holes 24 are formed in the left and right flanges 22 and 22 provided on the outer periphery of the hub 20 approximately in the axial direction of the wheel, and the nipple 14 to be locked to the rim 10 is provided on the hub 20. The wire spokes 12 are bent at an angle of about 110 ° from the vicinity of the spoke holes 24 toward the rim 10 so that the bent portions 18 are formed. Is formed.

  A seat surface made of a relatively large spherical surface is provided on the outer surface of the spoke hole 24, and the wire spoke 12 is inserted with a male screw that is screwed into the nipple 14 from the seat surface side when the hub 20 is assembled. The enormous head portion 16 provided on the side not carved with the male screw is locked to the seat surface to prevent it from coming off. Due to such a structure, when the wire spoke 12 is subjected to a strong tensile load, a force that stretches the bending of the bent portion 18 acts, and there is a case where the inner portion is cracked and cut.

In order to avoid such problems, the spoke holes 24 are formed in a radial direction (for example,
It is also proposed that part of the bent portion enters the spoke hole 24 so that no tensile force acts on the bent portion 18 (for example, Japanese Patent Application No. 2003-390618). issue).

However, according to the former, the structure is complicated and the weight is increased, the manufacturing process is increased and the production cost is increased, and the design process is difficult. Further, according to the latter, since the distance between the enormous head 16 and the bent portion 18 is shortened, when the wire spoke 12 is inserted into the spoke hole 24 and assembled, the bent portion 18 is inside the spoke hole 24. It was almost impossible to assemble without passing.
Japanese translation of PCT publication No. 8-502461

  One of the problems to be solved is that the weight of the enormous head 16 provided in the portion of the wire spoke 12 connected to the hub 20 is large, which causes an increase in the inertia weight of the wheel. The weight reduction is demanded. The second problem is that when a tensile force acts on the wire spoke 12, it is preferable to support the inner side of the spoke hole with the inner end of the spoke hole in order to suppress the action of the force to stretch the bent portion. This is to eliminate the poor assemblability that occurs when this structure is adopted.

  The present invention relates to a connection structure in which a light alloy hub in which two flanges having axial spoke holes are provided at an interval in the axial direction and a nipple locked to a rim are connected by wire spokes. A fitting portion that is inserted into the spoke hole in the wire spoke and an extending portion having a male screw that is screwed into the nipple, and a large radial gap is provided between the outer periphery of the fitting portion and the inner surface of the spoke hole. It is most important to provide a bent portion for directing the extended portion toward the nipple in the fitting portion, and to set the bending angle of the bent portion larger than the angle at the end of assembly. Features.

  In the wire spoke wheel according to the present invention, since the bent portion before the assembly of the wire spoke is set larger than the angle at the end of the assembly, the assembly portion of the wire spoke is inclined with respect to the spoke hole. Since it touches the inner surface of the spoke hole at two locations, near the enormous head and the bent portion of the wire spoke, and bites into the inner surface of the spoke hole when tightened, the contact area between the wire spoke and the spoke hole increases, and friction Therefore, the tensile force acting on the enormous head is reduced, so the area of the enormous head and the receiving seat for supporting it is small, the weight of the wire spoke can be reduced, and the assembly ability of the wire spoke to the spoke hole is improved. Productivity.

  Further, since a large gap is interposed in the radial direction between the outer periphery of the wire spoke fitting portion and the inner surface of the spoke hole, the inclination of the wire spoke in the spoke hole can be increased, and the bending portion can be bent. In addition to reducing the angle, since the bent portion is supported by the inner end of the inner surface of the spoke hole, it is possible to prevent the strength of the bent portion from being lowered due to the position of the spoke hole and the position of the nipple. Therefore, there is an advantage that it is possible to employ a spoke having a smaller diameter and contribute to weight reduction of the vehicle.

  FIG. 1 is a front view of a wire spoke 12 which is an embodiment of the apparatus of the present invention. Since the basic configuration is not significantly different from the conventional one, a portion sufficient for the description of the conventional example, for example, the point where the rim 10 and the hub 20 are connected by the wire spoke 12, the spoke hole 24, In the description of the present invention, the detailed description is omitted with respect to the fact that the direction of the rim 10 is greatly different and the bent portions 18 are provided in the wire spokes 12.

  In the present invention, the wire spoke 12 is formed of an elongated steel wire as shown in FIG. 2, and a male screw 12 a that engages with the nipple 14 is engraved at the end of the elongated portion 12 c fixed to the rim 10. A neck member 12b having a slightly larger diameter is formed at the end connected to the hub 20. The neck member 12b may be formed by upsetting one end of the elongated portion 12c, and a separately prepared member is connected to the elongated portion 12c with a screw (not shown) and integrated. There is also.

  The end portion of the neck member 12b is provided with a slightly large-diameter enlarged head 16, and a portion continuous with the enlarged head 16 forms a fitting portion 17 that fits into the spoke hole 24. A bent portion 18 that is bent in the direction of the elongated portion 12c is formed at a portion continuing from the joint portion 17. The fitting portion 17 side of the bent portion 18 is in a state of entering into the spoke hole 24, and the inner side is in contact with the inner end portion 24 a of the spoke hole 24. In the figure, α is a bending angle before the neck member 12b and the spoke hole 24 are assembled, and when the nipple 14 is tightened, the wire spoke 12 is bent to the position indicated by the phantom line by an angle γ, and the fitting portion 17 As shown in FIG. 3 to FIG. 6, the spoke hole 24 is inclined with respect to the axis of the spoke hole 24.

  Thus, by increasing the bending angle α in advance, the wire spoke 12 abuts against the inner end 24a of the spoke hole 24 inside the bent portion 18 during assembly, while the vicinity of the enormous head 16 is It abuts against the outer end 24 b of the spoke hole 24. The angle β is an angle at which the axis of the spoke hole 24 and the axis of the wire spoke 12 intersect when the wire spoke 12 is tightened, and is approximately 5 ° in this example.

  In the fitting portion 17, the gap between the outer periphery of the wire spoke 12 and the spoke hole 24 is set larger than that of the conventional one, and the fitting portion 17 is in the assembled state with respect to the spoke hole 24. It is set to be inclined more than before. Therefore, the wire spoke 12 is made closer to a straight line than in the conventional assembled state, and even when the wheel receives a large impact due to unevenness on the ground, it is less likely to be damaged.

  Since the wire spoke 12 is arranged so as to intersect with the spoke hole 24 in this way, when the wire spoke 12 is tightened by the nipple 14, the neck member 12b first rotates around the inner end portion 24a. The vicinity of the enormous head 16 tends to rotate in the direction opposite to the direction of the rim 10 and comes into contact with the outer end of the spoke hole 24.

  When the wire spoke 12 is tightened more strongly, the bent portion 18 crushes the inner end portion 24a, and the enormous head portion 16 crushes the outer end portion of the spoke hole 24 in the same manner, as shown in FIG. Biting into the hub 20 at two locations, the inner end 24a and the outer end 24b, increases the contact area between the neck member 12b and the hub 20. Reference numeral 26 shown by hatching is a pressure control portion of the fitting portion showing a state in which the wire spoke 12 bites into the hub 20, and reference numeral 27 is a pressure control portion of the enormous head.

FIG. 4 shows a modification of the enormous head 16, and the upper portion of the enormous head 16 is omitted from the drawing. As described above, when the fitting portion 17 of the wire spoke 12 is set to be inclined by about 5 ° with respect to the spoke hole 24, the enormous head portion 16 is also inclined with respect to the axis of the spoke hole 24 and in a biased position. Since it moves and comes into contact with the seating surface 25, the weight is reduced except for the portion corresponding to the position where it does not hit.
Moreover, since the enormous head portion 16 of the wire spoke can be passed from the inner end side of the spoke hole 24, the assemblability is dramatically improved.

It is a fragmentary sectional view which shows the principal part of a wire spoke wheel. It is a front view of a wire spoke. It is an expanded sectional view of the A section in FIG. It is an expanded sectional view equivalent to FIG. 3 which shows a modification. It is an arrow V figure in FIG. It is VI-VI sectional drawing in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rim 12 Wire spoke 12a Male thread 12b Neck member 12c Extension part 14 Nipple 16 Enlarged head 17 Locking part 18 Bending part 20 Hub 22 Flange 24 Spoke hole 24a Inner end part 24b Outer end part 25 Seating surface 26 of fitting part Pressure control part 27 Pressure control part of huge head

Claims (2)

  In the connection structure in which a light alloy hub in which two flanges each having an axial spoke hole are axially spaced apart and a nipple locked to a rim are connected by a wire spoke, the wire spoke A fitting portion inserted into the spoke hole and an extending portion having a male screw screwed into the nipple, and a large gap in the radial direction is interposed between the outer periphery of the fitting portion and the inner surface of the spoke hole. A wire spoke wheel in which a bent portion for directing the elongated portion toward the nipple is provided in the fitting portion, and a bending angle of the bent portion is set larger than an angle at the end of assembly.   The wire spoke wheel according to claim 1, wherein a curved portion constituting the above is disposed in the spoke hole, and the inner side of the bent portion is brought into contact with the inner peripheral edge of the spoke hole when the wire spoke is tightened.

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