Description THE TRUCK FOR A SKATEBOARD

Technical Field

[1] The present invention relates to a truck for a skateboard, and more particularly, to a truck for a skateboard in which a shaft having wheels coupled thereto is mounted to the center arms formed by bending a plate-shaped member, thereby improving shock absorption capability and increasing the jumping performance of the skateboard. Background Art

[2] As is well known in the art, a skateboard is a leisure product in which trucks fitted with wheels are coupled to the lower surface of a board to enable a user to ride on the ground. In order to provide a skateboard having excellent performance and functionality, research has actively been conducted, in particular, toward the development of a truck for a skateboard.

[3] FIGs. l(a) and l(b) are schematic perspective views illustrating a conventional truck for a skateboard, a prior art which is disclosed in Korean Patent Application No. 2001-0064136. The conventional truck has a base plate 30, a king pin 31, a king pin nut 34, and an axle housing 32. A urethane rubber 33 is inserted between the base plate 30 and the axle housing 32. In a state in which wheels are coupled to an axle 35 by axle nuts 36, the king pin 31 and the king pin nut 34 are assembled.

[4] In the conventional truck for a skateboard constructed as mentioned above, since the axle housing 32 is directly coupled to the base plate 30 and shock absorption is conducted only by the urethane rubber 33, shock absorption capability is degraded and the jumping performance of the skateboard is decreased.

[5] Another conventional truck for a skateboard is disclosed in Korean Utility Model

Application No. 1992-0004677. FIG. 2 is a perspective view of this conventional truck for a skateboard, and FIG. 3 is a cross-sectional view of FIG. 2. The truck for a skateboard has an arm 21 which is integrally formed with the truck at one end thereof and has an integral shaft hub 23 at the other end thereof, a boss 22 which is integrally formed with the truck, extends downward and has a circular flange 2212 and an opening 2211, and a semi-spherical elastomer 3 which is defined with an annular groove 31 on the outer surface adjacent to the upper end thereof and a groove 32 on the upper surface thereof. The shaft hub 23 has a circular bracket 24 integrally formed therewith.

[6] In this type of conventional truck having the arm 21, the elastomer 3 is brought into direct contact with the circular bracket 24 which is formed on the arm 21 to absorb shocks.

[7] The conventional truck encounters a problem in that the elasticity of the arm 21 cannot be sufficiently utilized, and since wheels are coupled to the shaft hub 23 connected to the arm 21, it is difficult to freely change the direction of the skateboard. Also, because the shaft hub 23 is connected to the arm 21 through welding, the welded part is likely to be fractured by fatigue induced by repeated use of the skateboard. Disclosure of Invention Technical Problem

[8] Accordingly, the present invention has been made in an effort to solve the problems occurring in the related art, and an object of the present invention is to provide a truck for a skateboard which is formed of a plate- shaped member in a manner such that both ends of the plate- shaped member are bent to define center arms, and a shaft having wheels coupled thereto is mounted to the center arms, thereby improving shock absorption capability, increasing jumping performance, and attaining excellent direction change ability of the skateboard.

[9] Another object of the present invention is to provide a truck for a skateboard in which center arms are integrally connected with each other, thereby further improving shock absorption capability and increasing jumping performance. Technical Solution

[10] In order to achieve the above object, according to one aspect of the present invention, there is provided a truck for a skateboard, having a shaft mounted thereto, the shaft having wheels coupled to both ends thereof, a coupling part having a through- hole projectedly formed in one side of a middle portion of the shaft, and a support part being projectedly formed on the other side of the middle portion of the shaft, wherein the truck is formed of a plate- shaped member in a manner such that both ends of the plate- shaped member are bent to face each other and define center arms, the coupling part is locked to one center arm by a connector, and the other center arm is defined with a pocket such that the support part can be inserted into the pocket with an elastomeric element coupled in the pocket.

[11] According to another aspect of the present invention, free ends of the center arms are inclined downward.

[12] According to still another aspect of the present invention, the center arms are formed by bending such that they are integrally connected with each other.

[13] According to a still further aspect of the present invention, the connector comprises a washer-integrated type bolt having a head part which has a rounded upper surface, is defined with a wrench groove on a center portion thereof, and is formed with a fastening protrusion on an edge thereof; a shock-absorbing rubber placed on upper and lower surfaces of the coupling part of the shaft; and a nut locked with a thread part of

the washer-integrated type bolt which passes through one center arm.

Advantageous Effects

[14] Thanks to the above features, the truck for a skateboard according to the present invention provides advantages in that it is possible to realize excellent shock absorption capability and jumping performance, and the direction of the skateboard can be easily changed. Further, by changing the material or thickness of the plate-shaped member constituting the truck, it is possible to construct a truck which is optimally suited for the weight of a rider.

Brief Description of the Drawings [15] The above objects and other features and advantages of the present invention will become more apparent after a reading of the following detailed description taken in conjunction with the drawings, in which: [16] FIGs. l(a) and l(b) are schematic perspective views illustrating a conventional truck for a skateboard;

[17] FIG. 2 is a perspective view illustrating another conventional truck for a skateboard;

[18] FIG. 3 is a cross-sectional view of FIG. 2;

[19] FIG. 4 is a perspective view illustrating the use of a truck for a skateboard in accordance with a first embodiment of the present invention; [20] FIG. 5 is a perspective view illustrating the truck for a skateboard in accordance with the first embodiment of the present invention;

[21] FIG. 6 is a cross-sectional view illustrating a washer-integrated type bolt;

[22] FIG. 7 is a cross-sectional view illustrating the coupling structure of a connector; and [23] FIG. 8 is a perspective view illustrating a truck for a skateboard in accordance with a second embodiment of the present invention.

[24] <Description of Reference Numerals for Main Parts of Drawings>

[25] 100: skateboard 200: truck for a skateboard

[26] 210: elastic member 230: center arm

[27] 232: pocket 234: elastomeric element

[28] 236: hole 250: reinforcing plate

[29] 300: shaft 310: wheel

[30] 320: coupling part

[31] 330: support part 400: connector

[32] 410: washer-integrated type bolt

[33] 412: head part

[34] 414: wrench groove 416: fastening protrusion

[35] 418: thread part 420: shock- absorbing rubber

[36] 430: nut

Best Mode for Carrying Out the Invention

[37] Reference will now be made in greater detail to a preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings and the description to refer to the same or like parts.

[38] FIG. 4 is a perspective view illustrating the use of a truck for a skateboard in accordance with a first embodiment of the present invention, and FIG. 5 is a perspective view illustrating the truck for a skateboard in accordance with the first embodiment of the present invention.

[39] Referring to FIGs. 4 and 5, the truck 200 for a skateboard in accordance with the first embodiment of the present invention is installed on the lower surface of a skateboard 100 and has a shaft 300 to which wheels 310 are coupled.

[40] The wheels 310 are respectively coupled to each end of the shaft 300. A coupling part 320 having a through-hole projects from one side of the middle portion of the shaft 300, and a support part 330 projects from the other side of the middle portion of the shaft 300.

[41] The truck 200 to which the shaft 300 is mounted is formed of a plate-shaped member 210. Both ends of the plate-shaped member 210 are bent to face each other and define two center arms 230. The coupling part 320 is locked to one center arm 230 by a connector 400, and the other center arm 230 has a pocket 232 defined therein such that the support part 330 can be inserted into the pocket 232. The pocket 232 is recessed sufficiently deeply therefor. Preferably, an elastomeric element 234 such as a urethane packing is coupled in the pocket 232 so that the free end of the support part 330 can be placed in the elastomeric element 234. Due to the presence of the support part 330 inserted into the pocket 232, the wheels 310 can be reliably held in place. When a skateboard turns, since the support part 330 finely pivots in the pocket 232 within a predetermined range, turning can be easily conducted.

[42] In the truck 200 for a skateboard according to the first embodiment of the present invention, in order to form the center arms 230 facing each other, both ends of the plate-shaped member 210 are bent twice such that the free ends of the center arms 230 are inclined downward to some extent. The two center arms 230 are separated from the base part of the plate-shaped member 210 which is directly locked to a board 100. When forming the center arms 230 by bending, the angles of the center arms 230 can be variously changed as desired. Thus, since a person having ordinary knowledge in the art could readily conceive of such a change in angle, it is to be noted that simply changing the angle falls within the scope of the present invention.

[43] The coupling part 320 projectedly formed on one side of the middle portion of the shaft 300 has the through-hole, and one center arm 230 associated with the coupling part 320 has a hole 236, so that the connector 400 is passed through the through-hole and the hole 236 and locks the coupling part 320 to the center arm 230. The connector 400 may comprise a conventional bolt or an elastic member such as a urethane rubber. Preferably, the connector 400 having the structure shown in FIGs. 6 and 7 is used.

[44] That is to say, the connector 400 is composed of a washer-integrated type bolt 410, a shock- absorbing rubber 420 and a nut 430. The washer- integrated type bolt 410 has a head part 412 which has a rounded upper surface, and is defined with a wrench groove 414 on the center portion thereof. A fastening protrusion 416 is formed on the edge of the lower surface of the head part 412. The shock- absorbing rubber 420 is placed on the upper and lower surfaces of the coupling part 320 of the shaft 300 and surrounds the washer- integrated type bolt 410. The nut 430 is locked to the thread part 418 of the washer-integrated type bolt 410 which passes through one center arm 230. In the case of the connector 400 according to the present invention, due to the fact that the wrench groove 414 is defined on the center portion of the head part 412 of the washer- integrated type bolt 410, it is possible to prevent the wrench groove 412 from being deformed due to friction. Also, since the fastening protrusion 416 is formed on the edge of the lower surface of the head part 412 of the washer- integrated type bolt 410, the shock-absorbing rubber 420 placed under the head part 412 can be reliably held in place.

[45] Next, the second embodiment of the present invention will be described. FIG. 8 is a perspective view illustrating a truck for a skateboard in accordance with a second embodiment of the present invention. Referring to FIG. 8, in the truck 200 for a skateboard in accordance with the second embodiment of the present invention, the center arms 230, which are formed by bending both ends of a plate-shaped member 210 to face each other, are integrally connected with each other. In other words, one center arm 230, having defined therein a pocket 232, and the other center arm 230 having defined therein a hole, are integrally connected with each other. Due to this connection structure, the durability of the truck 200 is improved, so that shocks transferred to the shaft 300 from the wheels 310 can be easily absorbed.

[46] In the first and second embodiments, a plate-shaped reinforcing piece 250 is placed under the center arm 230, such that it is possible for the truck 200 to sustain an increased load.

[47] Hereinbelow, the operation principle of the truck for a skateboard according to the present invention will be schematically explained. Unlike the conventional art, in the truck for a skateboard according to the present invention, both ends of the plate-shaped member 210 having a springing characteristic are bent to define the center arms 230,

and the shaft 300 having wheels coupled thereto is mounted to the center arms 230, whereby the shock absorption capability is improved and the jumping performance of the skateboard increases.

[48] As described above, in the present invention, the truck 200 is formed of the plate- shaped material having substantially the same elasticity as a leaf spring, and shocks are transmitted to the shaft 300 via wheels 310 which are brought into contact with the ground and roll thereon. Shocks transferred to the shaft 300 are effectively dispersed by the center arms 230, so that the shocks can be reliably mitigated. Industrial Applicability

[49] As is apparent from the above description, in the truck for a skateboard according to the present invention, a shaft having wheels coupled thereto is mounted to center arms which are formed by bending a plate-shaped member, so that shock absorption capability is improved, and the jumping performance of the skateboard increases. The structure of the truck according to the present invention can be applied not only to a skateboard but also to various vehicles having wheels, thus contributing to the leisure industry.

[50] In the drawings and specification, there have been disclosed typical preferred embodiments of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims.