阅读说明：本技术 辐式车轮 (Spoke type wheel ) 是由 山本敏宽 于 2019-08-21 设计创作，主要内容包括：本发明提供辐式车轮。辐式车轮具备轻合金制的轮辋、轮毂、以及连结轮辋和轮毂的多根钢丝辐条。轮辋具有相对于轮辋的宽度方向中央而设置于非对称位置的安装凸缘部,在安装凸缘部组装辐条并使辐条与轮毂连结。辐条相对于轮辋的宽度方向中央偏置配置。(The invention provides a spoke wheel. The spoke type wheel includes a rim made of light alloy, a hub, and a plurality of wire spokes connecting the rim and the hub. The rim has a mounting flange portion provided at an asymmetric position with respect to the widthwise center of the rim, and spokes are assembled to the mounting flange portion to connect the spokes to the hub. The spokes are arranged offset with respect to the widthwise center of the rim.)

1. A spoke type wheel is characterized by comprising:

a rim made of a light alloy;

a hub; and

a plurality of wire spokes connecting the rim and the hub,

the rim has a mounting flange portion provided at an asymmetric position with respect to a widthwise center of the rim, the spoke is assembled to the mounting flange portion and coupled to the hub,

the spokes are arranged offset with respect to the widthwise center of the rim.

2. A spoke wheel according to claim 1,

the mounting flange portions are two mounting flange portions located at different widthwise positions from the widthwise center of the rim.

3. The spoke wheel according to claim 2, comprising:

a first spoke group including spokes assembled to one of the two mounting flange portions; and

a second spoke group including spokes assembled to the other of the two mounting flange portions,

the tensioning angles of the spokes of the first spoke set and the spokes of the second spoke set are approximately equal.

4. A spoke wheel according to claim 2 or 3,

one of the two mounting flange portions is one of a pair of flange portions disposed at equal distances from a widthwise center at both widthwise outer portions of the rim,

the other of the two mounting flange portions is one of an inner flange portion disposed at a widthwise central position on an inner diameter surface of the rim or an inner flange portion disposed at an equal distance from the widthwise central position,

the rim is configured to be symmetrical with respect to the center in the width direction.

5. A spoke wheel according to claim 2 or 3,

the two mounting flange portions are disposed on one side with respect to a widthwise center including the widthwise center of the rim.

6. A spoke wheel according to claim 2,

one of the two mounting flange portions is one of a pair of outer flange portions that support the tire outer side portion,

the other of the two mounting flange portions is an inner flange portion that protrudes in an inner diameter direction on an inner diameter surface of the rim.

7. A spoke wheel according to claim 1,

a brake device including a brake disc and a brake caliper is disposed on a side of the cavity in the width of the rim where the spokes are not present.

Technical Field

The present invention relates to a spoke type wheel in which a hub and a rim are coupled by wire spokes, and more particularly, to a spoke type wheel suitably applied to a tubeless tire for a motorcycle.

Background

Conventionally, a rim made of a light alloy for a tubeless tire is provided with a flange portion on the inner diameter side of the rim, and spoke wires are connected to a hub by being locked to the flange portion so as to be prevented from coming off (jp 2013-35491 a), as shown in fig. 5 (a), the flange portion of the rim 3 is provided with one or a pair of flange portions having the same length from the width direction center O-O on the inner diameter side thereof, and the tension angles α of the left and right spoke groups are equally tensioned.

Therefore, the conventional spoke (more precisely, wire spoke) wheel 1 is configured to be bilaterally symmetrical in a vertical cross section (a cross section perpendicular to a circular plane of the rim), and the left and right spoke groups 2, 2 are disposed bilaterally symmetrically with respect to the center O-O in the rim width direction. Therefore, the brake disk 5 and the brake device 7 such as the brake caliper 6 are disposed at positions greatly offset from the widthwise center O-O of the spoked wheel 1 on which the tire 9 is mounted so as not to interfere with the symmetrically disposed left and right spoke groups 2, 2.

When a spoke wheel is attached to a suspension arm of a motorcycle, the suspension arm has a double-arm structure and a single-arm structure. Since the suspension arm of the double-arm structure has the support arms on the left and right sides, the axle is supported by the left and right support arms, and the spoke wheel is stably supported, the steering stability can be maintained even if the brake device is disposed at a position deviated from the rim in the width direction as described above.

Since the cantilever of the single-arm structure has the support arm only on one side and the brake device 7 is disposed on the outer side of the width of the two rims when the spoke wheel is supported by the cantilever, the brake device 7 is interposed between the spoke wheel and the support arm of the single-arm structure, and a gap between the support arm and the spoke wheel is enlarged, and the support of the spoke wheel is unstable, and the steering stability may not be sufficiently maintained.

Therefore, in the cantilever having the single-arm structure, although there are advantages in adjusting a chain, replacing a tire, and the like, it is difficult to apply a spoke wheel composed of a rim made of a light alloy.

Disclosure of Invention

The spoke wheel of the present invention is characterized by comprising: a rim made of a light alloy; a hub; and a plurality of wire spokes connecting the rim and the hub, wherein the rim has a mounting flange portion provided at an asymmetric position with respect to a widthwise center of the rim, the spokes are assembled to the mounting flange portion and connected to the hub, and the spokes are arranged offset with respect to the widthwise center of the rim.

Drawings

Other features of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention with reference to the attached drawings.

Fig. 1 is an overall perspective view (a radiation diagram) of a spoke type wheel showing an embodiment of the present invention.

Fig. 2 is a perspective view of a spoke wheel partially cut.

FIG. 3 is a cross-sectional view of the upper half of a spoke wheel.

FIG. 4 is a schematic partial cross-sectional view of a spoke wheel.

Fig. 5 (a) is a view showing a spoke wheel supported by a cantilever of a two-arm structure of a motorcycle.

Fig. 5 (b) is a view showing a spoke wheel supported by a cantilever of a single-arm structure of a motorcycle.

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings. As shown in fig. 1, 2, and 3, the spoke type wheel 11 includes a rim 12, a hub 13, and a plurality of wire spokes 15 connecting the rim 12 and the hub 13. The rim 12 has: left and right outer flange portions 12a, 12b rising in the outer diameter direction at outer ends in the width direction; bead seat portions 12c, 12d extending substantially horizontally on the inner sides in the width direction of both flange portions; a recessed portion 12e recessed in the inner diameter direction in the width direction of the bead seat portion; and an inner flange portion 12g disposed at the center of the inner diameter side surface 12f of the recessed portion 12e and projecting annularly toward the inner diameter side surface of the recessed portion inner diameter side surface 12 f.

The rim 12 is provided with left and right bead portions of a tire on left and right bead seat portions 12c, 12d, outer side surfaces of the bead portions are supported in contact with the left and right outer flange portions 12a, 12b, and the tire is mounted on the rim 12. The recessed portion 12e is recessed in a curved shape, and when the tire is mounted, the bead portion collapses and the entire circumference of the tire is received in the rim 12. The left and right outer flange portions 12a and 12b are formed of the same wall thickness structure, and can form spoke holes 17 for locking the wire spokes 15 while maintaining the rigidity of the rim 12.

The rim 12 is made of a light alloy (aluminum alloy, magnesium alloy, or the like), is formed by bending a profile formed by extrusion molding into a circular shape, welding both ends, and is formed by drilling the one outer flange portion 12a and the one inner flange portion 12 g. A plurality of spoke holes 17 are formed through the one outer flange portion 12a, and the one outer flange portion 12a having the spoke holes serves as an attachment flange portion. A plurality of spoke holes 19 are formed through the inner flange portion 12g, and the inner flange portion 12g having the spoke holes serves as a mounting flange portion. The spoke holes 17 extend substantially in the radial direction along the rising angle of the outer flange portion 12a, and the spoke holes 19 penetrating the inner flange portion 12g may be holes extending substantially in the horizontal direction or inclined holes inclined in the radial direction toward the spoke side.

The hub 13 is formed of a cylindrical member having a hole 13a for fitting the axle, and a plurality of right and left lug portions 13d, 13e protruding in the outer diameter direction are formed in the circumferential direction on the right and left outer circumferential surfaces of the cylindrical member at predetermined intervals in the width direction (axial direction). Holes 20 penetrating in the circumferential direction are formed in the left and right ear portions 13d, 13e, respectively.

Wire spokes 15 are stretched at a predetermined angle in the circumferential direction (generally referred to as a flat angle) and a predetermined angle in the width direction (generally referred to as a vertical angle) between spoke holes 17 formed in one outer flange portion (mounting flange portion) 12a of the rim 12 and holes 20 formed in the ear portions 13d which are the inner sides in the width direction of the hub 13, and wire spokes 15 are stretched at a predetermined flat angle and a vertical angle between spoke holes 19 formed in an inner flange portion (mounting flange portion) 12g of the rim 12 and holes 20 formed in the ear portions 13e which are the outer sides in the width direction of the hub 13. That is, a spoke group (hereinafter, referred to as a first spoke group a) including spokes 15 whose heads are locked to holes 17 formed in an outer flange portion 12a of a rim 12 is expanded to holes 20 of inner ear portions 13d on the opposite side in the width direction in a hub 13 by nipples 21, and a spoke group (hereinafter, referred to as a second spoke group B) including spokes 15 whose heads are locked to holes 19 formed in an inner flange portion 12g of the rim 12 and spokes 15 of the first spoke group a are expanded to holes 20 of outer ear portions 13e on the opposite side in the width direction in the hub 13 by nipples so as to intersect with each other in the width direction.

As shown in fig. 3, the spoke wheel 11 is formed by connecting the rim 12 and the hub 13 to each other so that the axial direction is parallel and the position in the width direction is determined by the wire spokes 15 of the first spoke group a and the second spoke group B that are arranged to be spaced apart from each other at a predetermined interval in the width direction, and the width direction angle α (the face angle, hereinafter referred to as a tension angle) of each wire spoke 15 of the first spoke group a and the tension angle α of each wire spoke 15 of the second spoke group B are made substantially equal by the tension adjustment of the nipples 21, whereby the wire spokes 15 of the spoke wheel 11 are arranged offset by a predetermined amount from the width direction center O-O of the rim 12 and the hub 13, and the rim 12 and the hub 13 are stably held in the above state.

In the spoke type wheel 11, the spokes 15 of the first spoke group a and the second spoke group B are arranged at positions offset to one side from the center O-O in the width direction of the rim 12, and the other side of the rim 12 where the spokes 15 are not present is a cavity C. Therefore, the brake disk 5 is fixed to the side surface of the hub 13 on the side of the cavity C in the width direction of the rim 12, which becomes the above-mentioned space state, and the brake disk 5 and the arm 10 are supported by the brake disk 5₂ Support arm 10c [ see (b) in FIG. 5 ]]The brake device 7 constituted by the disposed brake caliper 6 is disposed in the cavity C of the rim 12. Therefore, as shown in fig. 5 (b), the spoke wheel 11 having the brake device 7 disposed within the width of the rim 12 without interfering with the spokes 15 is supported by the arm 10 having a single-arm structure₂。

The inner flange portion 12g of the spoke wheel 11 is disposed at the center of the recessed portion 12e, i.e., the widthwise center O-O of the rim 12. The left and right outer flanges 12a, 12b are each formed of the same thickness structure. Therefore, the aluminum alloy profile forming the rim 12 is configured to be bilaterally symmetrical. A spoke hole 17 is formed in one outer flange portion 12a of the round rim formed of the profile to serve as an attachment flange portion. In the spoke type wheel 11, the spokes 15 of the first spoke group a are assembled to the one outer flange portion 12a, and the spokes 15 of the second spoke group B are assembled to the center inner flange portion 12 g.

Since the spoke wheel 11 has a symmetrical cross section, workability is improved. Further, depending on traffic regulations such as left-hand traffic and right-hand traffic, there is a possibility that the mounting position of a drive source member such as a sprocket assembled to a radial wheel and the position of a support arm of a cantilever having a single-arm structure may be different from each other in the left-hand direction and the right-hand direction. In this case, the spoke type wheel 11 may be selected from among the left and right outer flange portions 12a, 12b by forming the spoke holes 17 therein. For example, when the spokes 15 are arranged offset to the left in the motorcycle traveling direction, the spokes are assembled into spoke holes formed in the left outer flange portion 12b and the spokes are assembled into the central inner flange portion 12 g. Thus, the common rim 12 can be used regardless of whether the spokes are arranged left or right.

As shown in fig. 5 (b), the cantilever 10 of the single-arm structure₂The support arm 10c is provided only on one side, but even if the spoke wheel 11 having the brake device 7 housed in the width direction of the rim 12 supports the axle S on the support arm 10c by a single-arm structure, the spoke wheel 11 can be stably supported by the suspension arm 10 at a position close to the support arm 10c₂. Thus, the spoke type wheel 11 in which the spokes 15 are arranged offset can be applied to the cantilever 10 of the single-arm structure₂. Even in the cantilever 10 of single-arm type structure₂The spoke wheel 11 can be stably supported by the support arm 10c, so that the steering stability of the motorcycle can be ensured, and a sprocket can be attached to the outer side of the support arm 10 c. Thus, the offset spoke wheel 11 is mounted on the cantilever 10 having a single-arm structure₂In this case, the double-arm cantilever 10 can be used at the same weight ratio as the cantilever, so that the adjustment and replacement of the chain and the replacement of the tire can be improved₁In contrast, the rigidity can be improved. Further, since the spoke type wheel 11 connects the spokes 15 by the flange portions 12a, 12g, it is preferable to install a tubeless tire, and it is possible to improve weight reduction by the rim 12 and the wire spokes 15 made of a light alloy, and it is possible to connect the cantilever 10 of the single-arm structure₂In combination, the unsprung weight is reduced.

FIG. 4 shows an offset spoke arrangementVarious spoke wheels. Spoke wheel 11 shown in fig. 4 (a)₁Basically, the same as the previous embodiment shown in fig. 1 to 3, but the shape of the recessed portion 12e of the rim is slightly different. That is, although the recessed portion 12e of the rim 12 of the previous embodiment shown in fig. 1 to 3 is formed by an arc surface and the inner flange portion 12g is provided at the center top portion of the recessed portion inner diameter side surface 12f formed by an arc surface in the same manner, the rim 12 of the present embodiment is configured to have a circular flange portion 12g₁The recessed portion 12e and the bead seat portions 12c and 12d form a stepped portion 12h therebetween, and are formed in a shape of a prism. An inner flange portion 12g is also provided at a widthwise central portion O-O of the recessed portion inner diameter side surface 12f, which is formed of a substantially flat surface. The position of the inner flange 12g is not limited to the center in the width direction, and may be any position such as a position formed to protrude inward from the inner diameter side surface 12f extended from the step portion 12 h. The shape of the recessed portion 12e may be any shape. This case is also the same as the other embodiments shown in fig. 4.

One of the outer flanges 12a and 12B formed in a thick shape 12a is formed with a spoke hole 17 to form one attachment flange portion, and the wire spokes 15 forming the first spoke group a are stretched between the hub, and the inner flange 12g as the attachment flange portion is formed with spoke holes 19 to stretch the wire spokes 15 forming the second spoke group B between the hub and the attachment flange portion.

In fig. 4 (b), the rim 12 is provided₂In the concave portion 12e, left and right inner flange portions 12g1, 12g2 are formed on the extension lines of the left and right collapsed portions 12h, 12h so as to project in the inner diameter direction of the concave portion 12 e. Therefore, the left and right outer flange portions 12a, 12b have the same wall thickness structure, and the rim 12 is matched thereto in the same manner as in the previous embodiment₂Is bilaterally symmetrical in cross section with respect to the widthwise center O-O. Thus, as in the case described above, the spokes 15 can be selectively fitted into the right outer flange portion 12a and the right inner flange portion 12g1, respectively, and can be selectively formed so as to face the rim 12₂Right offset spoke wheel 11₂And spokes 15 fitted into the left outer flange portion 12b and the left inner flange portion 12g2, respectively, to the rim 12₂Left offset spoke wheel of (a).

In addition, the spoke type wheel 11 is described above₂In use, relative to the rim 12₂The widthwise center O — O of (a) is located at the outer flange portion 12a (or 12b) and the inner flange portion 12g1 (or 12g2) which are the same side in the widthwise direction, but the spokes 15 may be assembled to the outer flange portion 12a (or 12b) and the inner flange portion 12g2 (or 12g1) which are different sides in the widthwise direction. At this point, though the spokes 15 are opposite the rim 12₂The offset is smaller toward the width direction side, and the ratio occupied by the cavity C is reduced. Therefore, although in the spoke type wheel 11₂In the above embodiments, the first spoke group a and the second spoke group B are arranged at relatively separated positions, and the spokes improve the coupling between the rim and the hub, but reduce the cavity space for the brake device and the like.

The spoke offset from the center O-O in the width direction of the rim is not limited to one direction in which both the first spoke group a and the second spoke group B are located on the same side with respect to the center O-O, but means that the first spoke group a and the second spoke group B are not symmetrical with respect to the center O-O in the width direction, and the support structure of the rim of both spoke groups is offset from the center O-O in the width direction. Furthermore, the spoke wheel 11₂Also as with the other embodiments, the spoke tensioning angle α of the first spoke group a and the spoke tensioning angle α of the second spoke group B are designed to be the same.

Spoke wheel 11 shown in fig. 4 (c)₃The spoke attachment flange portion is formed by modifying the outer flange portion. At the rim 12₃In addition to the left and right outer flange portions 12a, 12b for supporting a tire having a thin wall structure, flange-like attachment flange portions 12i, 12j protruding outward are provided on extension lines of the bead seat portions 12c located on the lateral sides of the left and right outer flange portions 12a, 12 b. Further, an inner flange portion 12g protruding in the inner radial direction is provided at the widthwise center O-O of the recessed portion inner diameter side surface 12 f. The spoke holes 17 are formed in either (12i) of the left and right mounting flange portions 12i, 12j, the spokes 15 of the first spoke group A are assembled, and the spokes 15 of the second spoke group B are assembled to the inner flange portion 12g, thereby forming the spoke type wheel 11₃。

The rim 12₃The shape of the spoke attachment structure is also formed in a bilaterally symmetrical shape, and as in the above-described embodiment, the spokes can be connected by selecting either one of the left and right attachment flange portions 12i, 12j, and the offset positions of the spokes can be selected on both the left and right sides. The position of the inner flange portion 12g can be designed as an installation position in addition to the widthwise central position. The spoke type wheel 11₃The positions of the spokes in the width direction can be variously set, and the spoke type wheel can be made lightweight.

Rim 12 shown in fig. 4 (d)₄The flange portion includes not only the mounting flange portions 12i and 12j extending to the left and right outer sides but also a pair of inner flange portions 12g1 and 12g2 shown in fig. 4 (b). Thus, the rim 12₄The structure is also symmetrical to the left and right, as in the other embodiments. The spoke type wheel 11 can be configured by selectively combining either one of the left and right mounting flange portions 12i, 12j and either one of the left and right inner flange portions 12g1, 12g2₄. For example, the spoke holes 17 are opened in the right mounting flange portion 12i, the spokes 15 of the first spoke group a are assembled, the spoke holes 19 are formed in the right inner flange portion 12g1, and the spokes 15 of the second spoke group B are assembled. In addition to the above, there are combinations of the right mounting flange portion 12i and the left inner flange portion 12g2, the left mounting flange portion 12j and the right inner flange portion 12g1, and the left mounting flange portion 12j and the left inner flange portion 12g 2. In the present embodiment, various spoke wheels 11 based on the above-described combinations can be obtained₄。

Rim 12 shown in fig. 4 (e)₅The left and right mounting flanges 12k, 12l are formed so as to extend in the inner diameter direction of the outer flanges 12a, 12b and project inward. The inner flange 12g is formed at the widthwise center O-O portion of the depressed portion inner diameter side surface 12 f. Rim 12 of the present embodiment₅And also formed in bilateral symmetry. The spoke wheel 11 is configured by forming spoke holes 17 in one of the left and right mounting flange portions 12k, 12l, for example, the right mounting flange portion 12k, assembling the spokes 15 of the first spoke group a, and assembling the spokes 15 of the second spoke group B in the inner flange portion 12g₅. The spoke type wheel 11₅Can make the mounting flange part thin and realize light weightAnd the compactness in the width direction can be realized. The inner flange 12g is not limited to being provided at the center in the width direction, and may be provided at any position.

Rim 12 shown in fig. 4 (f)₆A pair of inner flanges 12g1 and 12g2 are provided symmetrically. The rim 12₆The left and right mounting flange portions 12k, 12l extending from the outer flange portions 12a, 12b are formed in the same manner as described above, and are bilaterally symmetrical. Therefore, as described in the embodiment of fig. 4 (d), the respective spoke wheels 11 are configured by selectively combining either one of the left and right mounting flange portions 12k, 12l with either one of the left and right inner flange portions 12g1, 12g2₆. For example, the spoke holes 17 are formed in the right mounting flange portion 12k, the spokes 15 of the first spoke group a are assembled, the spoke holes 19 are formed in the right inner flange portion 12g1, and the spokes 15 of the second spoke group B are assembled to form the spoke type wheel 11₆。

Although the right side (left side) mounting flange portion and the like are described as the right side and the left side, this is a convenient name determined in the direction of viewing the cross section, and if the viewing direction is changed, the left and right sides are also changed. The number of the mounting flange portions is not necessarily limited to two, and may be three or more, or may be one. The spoke wheel is preferably applied to a cantilever of a single-arm structure, but is not limited thereto, and may be applied to a cantilever of a double-arm structure, a front wheel, and a spoke wheel other than a motorcycle.

As described above, in the present embodiment, the spoke wheel (11) is characterized by including: a rim (12) made of light alloy; a hub (13); and a plurality of wire spokes (15) connecting the rim and the hub, wherein the rim (12) has flange portions (12a, 12g) attached at asymmetric positions with respect to a widthwise center (O-O) of the rim, the spokes (15) are assembled to the attachment flange portions and connected to the hub (13), and the spokes (15) are disposed offset with respect to the widthwise center (O-O) of the rim.

Since a plurality of mounting flange portions are provided at asymmetrical positions of the light alloy rim, and wire spokes are assembled to these mounting flange portions and connected to the hub, the light alloy rim and the wire spokes can be used to reduce the weight of the spoke type wheel, and the tubeless tire can be mounted.

Preferably, the mounting flange portion is two mounting flange portions (12a, 12g) located at different positions in the width direction from the center (O-O) of the rim in the width direction.

Accordingly, since the wire spokes are assembled by the two mounting flange portions having different lengths from the center in the width direction of the rim, the rim and the hub can be reliably coupled, and a spoke wheel having an offset arrangement can be obtained with a relatively simple structure.

The spoke type wheel is provided with a first spoke group (A) composed of spokes (15) assembled on one (12a) of the two mounting flange parts, and a second spoke group (B) composed of spokes (15) assembled on the other (12g) of the two mounting flange parts, wherein the tensioning angle (α) of the spokes (15) of the first spoke group (A) is approximately equal to the tensioning angle (α) of the spokes (15) of the second spoke group (B).

If the tightening angle of the spokes of the first spoke group and the tightening angle of the spokes of the second spoke group are made substantially equal in this way, a spoke wheel in which the rim and the hub are stably connected can be obtained.

One of the two mounting flanges is one of a pair of flange portions (12a, 12b) (12i, 12j) (12k, 12l) disposed at equal distances from the widthwise center on both widthwise outer portions of the rim, the other of the two mounting flanges is one of an inner flange portion (12g) disposed at the widthwise center position on the inner diameter surface of the rim or inner flange portions (12g1, 12g2) disposed at equal distances from the widthwise center, and the rim (12, 12) is a rim₁～12₆) The structure is symmetrical with respect to the center in the width direction.

Since the rim is symmetrical with respect to the center in the width direction, the spoke wheel can be easily processed, and the offset side of the spokes can be selected on the left and right sides of the rim, so that the offset spoke wheel can be used for any motorcycle.

The two mounting flange sections (12a, 12g) are disposed on one side with respect to a widthwise center including a widthwise center (O-O) of the rim (12).

In this way, since the spokes are arranged closer to one side in the width direction of the rim, a relatively large cavity space can be provided in the rim width on the side opposite to the spokes, and the brake device and the like can be easily arranged.

One of the two mounting flange portions is one (12a) of a pair of outer flange portions (12a, 12b) that support the tire outer portion, and the other of the two mounting flange portions is an inner flange portion (12g) that protrudes in the inner diameter direction on the inner diameter surface of the rim.

In this way, one of the pair of outer flange portions is used as the mounting flange portion, and the inner flange portion provided on the rim inner diameter surface is used as the other mounting flange portion, so that the offset spoke type wheel can be obtained with a relatively simple configuration.

For example, referring to fig. 5 (b), a brake device (7) including a brake disc (5) and a brake caliper (6) is disposed on the side of the cavity (C) within the width of the rim (12) where the spokes (15) are not present.

Therefore, the brake device can be disposed on the cavity side where no spoke exists within the width of the rim, and the spoke type wheel can be applied to the cantilever of the single-arm structure.

While the invention has been described with reference to the preferred embodiments, it is to be understood that the invention is not limited to the disclosed preferred embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.