JP4303067B2 - Motorcycle wheel and casting mold - Google Patents

Description

The present invention relates to a motorcycle wheel formed by connecting a hub portion and a rim portion with spokes, and a casting mold for the same.

A conventional spoke wheel for a motorcycle has a configuration in which a hub portion and a rim portion are connected by a large number of spokes. The hub portion is composed of a cylindrical bearing portion positioned at the shaft center and generally disc-shaped flange portions formed at both axial ends of the bearing portion (see, for example, Patent Document 1).
Japanese Utility Model Publication No. 6-39501

Since the hub portion of the conventional spoke wheel adopts a structure in which flange portions are formed at both ends of the bearing portion located at the shaft center, the casting mold for the hub portion is axially and perpendicular to the axis. There is a problem that a total of four divided molds are required, so that the mold structure is complicated and the manufacturing cost is high.

The present invention has been made in view of the above-described conventional problems, and it is an object of the present invention to provide a motorcycle wheel and its casting mold that can reduce the number of divisions of the casting mold and reduce the mold cost. Yes.

The invention of claim 1 is a motorcycle wheel comprising a hub portion constituting an axial center portion and a rim portion constituting an outer peripheral portion connected by a plurality of spokes, wherein the hub portion is a cylindrical bearing tube portion. And an annular large-diameter portion that is disposed so as to be coaxial with one end of the bearing tube portion, is provided with a boss portion that engages with the spoke portion, and has an inner diameter larger than the outer diameter of the bearing tube portion , A boss portion that is disposed coaxially with the other end of the bearing tube portion, engages with the spoke portion, has an outer diameter smaller than the outer diameter of the large diameter portion, and is external to the bearing tube portion. An annular small-diameter portion having an inner diameter larger than the diameter, and a rib extending in the axial direction of the bearing tube portion and connecting the inner surface of the small-diameter portion and the large-diameter portion and the outer surface of the bearing tube portion , The height in the outer diameter direction is lower than the height in the outer diameter direction of the boss portion of the large diameter portion, and the above It is characterized by higher than the outer diameter direction of the height of the boss portion of the diameter.

A second aspect of the present invention, in claim 1, the upper Kitai diameter portion and the rim portion are connected by a short spokes, it is characterized in that the smaller-diameter portion and the rim portion are connected by elongated spokes .

According to a third aspect of the present invention, in the second aspect, the disk plate that rotates together with the wheel is bolted and fixed to the outer end surface of the large-diameter portion, and the radial direction from the point where the large-diameter portion disk plate is fixed. The short spokes are connected to the outside.

According to a fourth aspect of the present invention, in the second or third aspect, the ribs are arranged so as to radiate from the shaft center of the bearing tube portion, and a disk plate that rotates together with the wheel is fastened to the ribs by bolting. It is characterized by being.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the rib includes a large rib extending from the large-diameter side end of the small-diameter portion to the large-diameter portion, and a large-diameter from the large-diameter side end of the small-diameter portion. The large ribs and the small ribs are characterized in that the large-diameter side ends have a maximum thickness and become thinner as they move away from each other in the axial direction.

A sixth aspect of the present invention is a casting mold for a motorcycle wheel according to any one of the first to sixth aspects, comprising a left mold and a right mold divided into two in the axial direction. The mating surface with the right mold includes a first mating surface disposed along the end surface of the large diameter portion and a second mating surface disposed along the large diameter side end surface of the small diameter portion. It is characterized by having.

According to the first aspect of the present invention, a cylindrical bearing tube portion, annular large-diameter portions and small-diameter portions disposed at one end and the other end of the bearing tube portion, and an axial direction of the bearing tube portion are extended. , since the structure having a rib connecting the outer surface of the inner surface and the bushing section of the said small diameter portion and the large diameter portion, is possible to construct a concrete mold casting, in two types which are divided in the axial direction In addition, the mold structure can be simplified, the number of mold points can be reduced, and the manufacturing cost can be reduced as compared with the conventional axial direction and perpendicular direction.

According to the invention of claim 2, the upper Kitai diameter portion and the rim portion are connected by short spokes, since the connection between the small diameter portion and the rim portion in the long spokes, the hub portion with a simple mold structure A spoke wheel that can be cast can be realized.

According to the invention of claim 3, because the disk plate of the braking device is bolted and fixed to the outer end face of the large diameter portion, and the short spoke is connected to the radially outer side from the disk plate fixing point of the large diameter portion. The rigidity of the disk plate fixing portion is increased, and the vibration of the disk plate during braking, and hence abnormal noise (brake squeal) during braking, can be prevented or suppressed.

According to the invention of claim 4, the bearing portion of the hub portion and the large diameter portion and the small diameter portion are connected by a plurality of radially arranged ribs, and the disk plate is bolted and fixed to the rib. It is possible to prevent or suppress brake noise during braking by increasing the rigidity of the disk plate fixing portion while reducing the weight of the portion.

According to the invention of claim 5, the rib is composed of a large rib and a small rib formed subsequently thereto, and the boundary between the large rib and the small rib is set to the maximum thickness, and from here the axial direction Since it is configured so as to become farther away, the two molds divided in the above-described axial direction can be cast without any trouble.

According to the invention of claim 6, the casting mold is configured by a left mold and a right mold divided in two in the axial direction, and a mating surface of the left mold and the right mold is along the end surface of the large diameter portion. Since the first mating surface arranged as described above and the second mating surface arranged along the large-diameter side end surface of the small-diameter portion are provided, the hub portion of the motorcycle wheel described above is provided. Casting is possible with only two molds divided in the axial direction.

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 12 are views for explaining a motorcycle wheel and its casting mold according to an embodiment of the present invention. FIG. 1 is a sectional front view of a front wheel, FIG. 2 is a side view, and FIG. 4 are left and right side views, FIGS. 5 and 6 are cross-sectional front views of the hub, FIGS. 7 to 10 are cross-sectional front views of the main part, and FIGS. 11 and 12 are cross-sectional front views of the casting mold. .

In the figure, reference numeral 1 denotes a front wheel, which is rotatably supported by bearings 4 and 4 by an axle 3 inserted and fixed between boss portions 2a and 2a of left and right front fork bodies 2 and 2. Yes.

The front wheel 1 is a so-called spoke wheel in which a hub portion 5 constituting an axial center portion and a rim portion 6 constituting an outer peripheral portion are connected by a large number of spokes 7. The spoke 7 has a plurality of short spokes 7a that connect the rim portion 6 and a large-diameter portion 10 of the hub portion 5 to be described later, and a plurality of short-diameter portions 11 of the rim portion 6 and the hub portion 5 that will be described later. It is comprised from the elongate spoke 7b.

The rim portion 6 is an annular shape in which vertical wall portions 6b and 6b are integrally formed on both edges of a bottom wall portion 6a having a substantially dish-shaped cross section, and the bead of the tire 8 is formed on the inner surface of the vertical wall portion 6b. The part 8a is engaged.

The hub portion 5 includes a cylindrical bearing tube portion 9 positioned at the shaft center, an annular large-diameter portion 10 disposed coaxially with one end of the bearing tube portion 9, and a coaxial shaft with the other end. And an annular small-diameter portion 11 which is arranged so as to be formed. The bearing tube portion 9, the large diameter portion 10, and the small diameter portion 11 are a plurality of (six in this embodiment) plate-like ribs 12 that are arranged radially and centered on the axis. Are integrally coupled.

In the bushing section 9, the large diameter portion 10 side end portion from which the ridge line portion 9a portions intersecting the axially inner surface is at the maximum diameter of the vertical wall 11b of the small diameter portion 11, the small diameter portion 11 side end portion Draft angles a and a ′ that gradually become smaller in diameter are formed. Further, bearing holes 9b into which the bearing 4 and the seal member 4a are fitted and inserted are formed on the inner surfaces of both end portions in the axial direction of the bearing tube portion 9.

The said large diameter part 10 consists of the annular body 10a which makes | forms the L shape which has the vertical wall 10b and the horizontal wall 10c when it sees in a cross section, and is arrange | positioned so that the said vertical wall 10b may be located in an axial direction outer side. .

A plurality (9 in this embodiment) of spoke bosses 10d are integrally projected at equal angular intervals on the outer peripheral surface of the torus 10a, and are formed so as to penetrate in the circumferential direction of the spoke bosses 10d. The axial end 7c of the short spoke 7a is engaged with the spoke hole 10e. The outer end portion 7d of the short spoke 7a is screwed into a nipple 7e engaged with the bottom wall portion 6a of the rim portion 6.

Further, a disc boss 10f for attaching a brake disc is projected from the outer surface of the vertical wall 10b.

The small diameter portion 11 has a shape obtained by reducing the diameter of the large diameter portion 10. That is, the small-diameter portion 11 is arranged such that an annular body 11a having a L-shaped cross section composed of a vertical wall 11b and a lateral wall 11c is disposed so that the vertical wall 11b is positioned on the inner side in the axial direction, and the outer periphery of the annular body 11a. A plurality of (9 in this embodiment) boss portions 11d are integrally projected on the surface at equal angular intervals. The axial end portion 7c of the long spoke 7b is engaged with the spoke hole 11e of the boss portion 11d. The outer end portion 7d of the long spoke 7b is screwed into a nipple 7e engaged with the bottom wall portion 6a of the rim portion 6.

Each of the ribs 12 includes a large rib 12a located on the large diameter portion 10 side from the ridge line portion 9a and a small rib 12b located on the small diameter portion 11 side. In particular, the large rib 12a is further protruded rightward from the axially outer end face of the large diameter portion 10 from the axially inner side surface of the vertical wall 11 b of the small-diameter portion 11 through the large-diameter portion 10 It extends to do. The small rib 12b extends from the ridgeline portion 9a, that is, the small-diameter end of the large rib 12a through the small-diameter portion 11 toward the outside in the axial direction. In this way, the bearing tube portion 9 and the small-diameter portion 11 and the large-diameter portion 10 are firmly connected by the rib 12.

Further, the thickness of the large rib 12a is set so as to decrease from the ridge line portion 9a to the axially outer side (large diameter portion 10 side). Further, the thickness of the small rib 12b is set to be thinner toward the outer side in the axial direction from the ridge line portion 9a, and in this way, draft angles b and b 'at the time of casting are ensured.

A brake disc 13 is disposed on the disc boss portion 10f of the large-diameter portion 10, and is fixed by a bolt 14 screwed into a screw hole 10g formed in a joint portion between the large rib 12a and the disc boss portion 10f. Has been. Reference numeral 15 denotes a brake caliper that sandwiches the brake disk 13 and generates a braking force, and is detachably attached to the rear side of the front fork 2.

11 and 12 show a mold 20 for casting the hub portion 5 of the present embodiment, FIG. 11 is a cross-sectional view at the same position as FIG. 5, and FIG. 12 is the same position as FIG. 6 and FIG. The cross-sectional state is shown. In FIGS. 11 and 12, “′” is attached to the reference symbol to indicate a corresponding portion of the hub portion 5.

The mold 20 includes a left mold 21 and a right mold 22 that are divided into two in the axial direction. The mating surfaces of the left mold 21 and the right mold 22 are arranged along the first mating surface D1 arranged along the end surface of the large diameter portion 10 and the large diameter portion side end surface of the small diameter portion 11. It is comprised from the arrange | positioned 2nd mating surface D2 and the 3rd mating surface D3 located inside the bearing cylinder part 9. FIG.

In the present embodiment, the hub portion 5 has the large-diameter portion 10 and the small-diameter portion 11 having a smaller diameter than this, and the small-diameter portion 11 side in the axial direction starts from the large-diameter portion 10, so that the smaller diameter is formed. The casting mold 20 for casting the hub portion 5 can be constituted by two molds of a left mold 21 and a right mold 22 that are divided in the axial direction. Specifically, as shown in FIGS. 11 and 12, the mating surfaces of the left mold 21 and the right mold 22 are arranged so that the first mating surface D1 arranged along the end surface of the large-diameter portion 10 and the above-mentioned Since it has the 2nd mating surface D2 arrange | positioned along the large diameter part side end surface of the small diameter part 11, and the 3rd mating surface D3 located inside the bearing cylinder part 9, the said hub part 5 is used. Casting is possible with only two dies 21 and 22 divided in the axial direction, and the die structure can be simplified and the number of dies can be reduced as compared with the conventional case where the die is divided in the axial direction and the direction perpendicular to the axis, and the manufacturing cost can be reduced. .

In configuring the hub portion 5, the large-diameter portion 10 is disposed at one axial end portion of the hub portion 5, and the small-diameter portion 11 is disposed at the other end portion, and the large-diameter portion 10, the rim portion 6, and the like. Are connected by the short spokes 7a, and the small-diameter portion 11 and the rim portion 6 are connected by the long spokes 7b, so that the spoke wheel can be configured without hindrance while the hub portion 5 can be cast with a simple mold structure.

Furthermore, since the disc plate 13 of the braking device is bolted and fixed to the outer end surface of the large-diameter portion 10 and the short spoke 7a is connected radially outward from the disc plate fixing point, the rigidity of the disc plate fixing portion is increased. The vibration of the disc plate 13 during braking, and hence abnormal noise (brake squeal) during braking, can be prevented or suppressed. In this case, the disk plate 13 is bolted and fixed to the plurality of radially arranged ribs 12 that connect the bearing tube portion 9 of the hub portion 5 to the large diameter portion 10 and the small diameter portion 11. It is possible to prevent or suppress brake noise during braking by increasing the rigidity of the disk plate fixing portion while reducing the weight.

Further, the rib 12 is composed of a large rib 12a and a small rib 12b formed subsequently thereto, and the boundary between the large rib 12a and the small rib 12b is set to the maximum thickness, and becomes thinner as they are separated from each other in the axial direction. Since the rib 12 is provided, the hub portion 5 can be cast without any trouble using only the two molds 21 and 22 divided in the axial direction described above.

1 is a cross-sectional front view of a motorcycle wheel according to an embodiment of the present invention. It is a side view of the said wheel. It is the left view seen from the large diameter part side of the hub part of the said wheel. It is the right view seen from the small diameter part side of the said hub part. FIG. 5 is a cross-sectional front view (cross-sectional view taken along line V-V in FIG. 4) of the hub portion. It is sectional drawing (VI-VI line sectional drawing of FIG. 4) of the said hub part. It is sectional drawing (VII-VII sectional view taken on the line of FIG. 4) of the said hub part. It is sectional drawing (the VIII-VIII sectional view taken on the line of FIG. 4) of the said hub part. It is sectional drawing (the IX-IX line sectional view of Drawing 3) of the above-mentioned hub part. It is sectional drawing (XX sectional drawing of FIG. 4) of the said hub part. FIG. 6 is a cross-sectional view (corresponding to FIG. 5) of the hub part mold. It is sectional drawing (corresponding to Drawing 6) of the above-mentioned mold for hub parts.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wheel for motorcycles 4 Bearing 5 Hub part 6 Rim part 7 Spoke 7a Short spoke 7b Long spoke 9 Bearing cylinder part (bearing part)
10 Large diameter portion 11 Small diameter portion 13 Disc plate 12 Rib 12a Large rib 12b Small rib 20 Casting mold 21 Left mold 22 Right mold D1 First mating surface D2 Second mating surface

Claims (6)

In a motorcycle wheel formed by connecting a hub portion constituting an axial center portion and a rim portion constituting an outer peripheral portion by a plurality of spokes,
The hub part is
A cylindrical bearing cylinder,
An annular large-diameter portion that is disposed so as to be coaxial with one end of the bearing tube portion, is provided with a boss portion that engages with the spoke portion, and has an inner diameter larger than the outer diameter of the bearing tube portion;
A boss portion that is disposed coaxially with the other end of the bearing tube portion, engages with the spoke portion, has an outer diameter smaller than an outer diameter of the large diameter portion, and An annular small diameter portion having an inner diameter larger than the outer diameter ;
A rib extending in the axial direction of the bearing tube portion and connecting the inner surface of the small diameter portion and the large diameter portion and the outer surface of the bearing tube portion;
The height in the outer diameter direction of the rib is lower than the height in the outer diameter direction of the boss portion of the large diameter portion and higher than the height in the outer diameter direction of the boss portion of the small diameter portion. Motorcycle wheel to be used.   The motorcycle wheel according to claim 1, wherein the large-diameter portion and the rim portion are connected by a short spoke, and the small-diameter portion and the rim portion are connected by a long spoke.   3. The disk plate that rotates together with the wheel is bolted and fixed to the outer end surface of the large diameter portion according to claim 2, and the short spoke is connected radially outward from the point where the disk plate of the large diameter portion is fixed. A motorcycle wheel characterized by being made.   4. The rib according to claim 1, wherein the rib is arranged so as to radiate from the axis of the bearing tube portion, and a disk plate that rotates together with the wheel is bolted to the rib. Motorcycle wheel characterized by   5. The rib according to claim 4, wherein the rib extends from the large-diameter side end of the small-diameter portion to the large-diameter portion, and the small rib extends from the large-diameter-side end of the small-diameter portion to the opposite large-diameter portion. The wheel for a motorcycle according to claim 1, wherein the large rib and the small rib have a maximum thickness at the end portion on the large diameter side, and are thinned away from each other in the axial direction.   A casting mold for a motorcycle wheel according to any one of claims 1 to 5, comprising a left mold and a right mold divided in two in the axial direction, and a mating surface of the left mold and the right mold is An automatic device comprising: a first mating surface disposed along the end surface of the large-diameter portion; and a second mating surface disposed along the large-diameter portion side end surface of the small-diameter portion. Mold for casting wheels for motorcycles.

Images