Description SKATEBOARD

Technical Field

[1] The present invention relates, in general, to skateboards, and, more particularly, to a skateboard, in which the elasticity of a coupling member is improved to increase the thrust thereof, separate front and rear board sections and the coupling member are easily coupled to or separated from each other using keys, and position-adjustable casters are provided on the bottoms of the board sections, thus enabling the adjustment of the distance between wheels depending on a rider's body condition. Background Art

[2] A conventional skateboard includes a plate having the shape of a long ellipse, and two wheel sets provided on the bottom of the plate. Each wheel set has two wheels. Such a conventional skateboard is maneuvered as follows.

[3] That is, when a rider rides on level ground, one foot is used for pushing so as to propel the skateboard. Meanwhile, when the rider performs a turning action while riding, he or she tilts the board to the left or right relative to the traveling direction using his or her feet.

[4] However, the conventional skateboard is problematic in that there is no method of moving the skateboard without requiring a rider's foot to contact the ground. Even if there were a method of moving the skateboard without contacting the ground with one's feet, the method would be very difficult, so that only a rider having excellent skills could perform the method.

[5] Further, when the skateboard is turned while riding, the plate may be inclined to a side beyond a predetermined extent. In this case, since the wheels contact the plate, it is impossible to tilt the plate a desired amount, and thus the turning radius is undesirably large.

[6] Thus, in order to solve the problems, a skateboard which is constructed so that the board is divided into two board sections and casters are mounted to the bottoms of the divided board sections has been proposed. As such, the skateboard which is divided into two board sections is disclosed in US Patent Publication No. 4,076,267, US Patent Publication No. 4,082,306, Japanese U.M. Laid-Open Publication No. Hei 1-117385, Japanese U.M. Laid-Open Publication No. Hei 13-29663, Korean Patent No. 394848, and Korean Patent No. 505754.

[7] Meanwhile, a skateboard which is divided into two board sections and is propelled by oscillating the skateboard is disclosed in US Patent Publication No. 1,056,357 and Korean Patent Laid-Open Publication No. 2002-28361.

[8] According to the cited documents, the skateboard is provided with two divided board sections, which are coupled to each other via a coupling member having elasticity. Casters are mounted to the bottoms of the board sections.

[9] The cited documents are the same as each other in that the skateboard is propelled by oscillating the two divided board sections. However, the cited documents are problematic in that the coupling member is fastened to the board sections using bolts and nuts, so that it is difficult to assemble and disassemble the coupling member, and thus the length of the skateboard cannot be reduced when it is stored. Moreover, the casters are mounted to the bottoms of the board sections at fixed positions. Even if the casters were movable, as in Korean Patent No. 505754, it would not be easy to secure the casters at predetermined positions in a groove after the position of each caster is adjusted.

Disclosure of Invention Technical Problem

[10] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a skateboard, in which the elasticity of a coupling member is improved, thus increasing the thrust, which enables easy assembly/disassembly of the coupling member, and which allows the positions of the casters to be easily adjusted. Technical Solution

[11] In order to accomplish the object, the present invention provides a skateboard including front and rear board sections, a coupling member, a protective pipe, a key, a guide part, a slide member, and a caster. Each of the front and rear board sections has a cover which is designed to provide a good appearance, and a main body having a holder which is provided on a lower portion of the main body and has a space therein, a key groove which is provided on an upper portion of the main body, and a position adjusting hole which is formed in a bottom of the main body. The coupling member couples the front and rear board sections to each other such that the front and rear board sections are spaced apart from each other, and is made of a synthetic resin material so that the coupling member is elastically restored when the coupling member is twisted or bent, and includes a locking protrusion which is provided on each of opposite ends of the coupling member and is fitted into a cross-shaped locking hole formed in the holder so as to prevent rotation of the coupling member, a flute which is formed in the coupling member in a lengthwise direction thereof and increases elasticity of the coupling member, and a key groove which is provided in the coupling member to correspond to a key groove of each of the board sections, thus communicating with the key groove of each of the board sections. The protective pipe is

fitted over the coupling member, and prevents damage to the coupling member.

[12] The key is inserted into the key grooves of each of the board sections and the coupling member. The guide part is mounted to a bottom of each of the front and rear board sections, and has a slide groove so that a caster body is fitted into the slide groove. The slide member is mounted to a central shaft of the caster mounted to the bottom of each of the front and rear board sections, and is inserted into the position adjusting hole. The caster includes a bracket rotatably supporting a wheel which is mounted to the bottom of each of the front and rear board sections so as to move the board sections, and a block for holding the bracket.

[13]

Brief Description of the Drawings

[14] FlG. 1 is an exploded perspective view showing the construction of a skateboard, according to the present invention;

[15] FlG. 2 is a sectional view showing the construction of the skateboard, according to the present invention;

[16] FlG. 3 is an exploded perspective view showing the coupling of a board section with a coupling member, which are important parts of the present invention;

[17] FlG. 4 is a sectional view showing an embodiment of a coupling member, which is an important part of the present invention;

[18] FIGS. 5 and 6 are a perspective view and a sectional view showing another embodiment of a coupling member, which is an important part of the present invention;

[19] FlG. 7 is an enlarged exploded perspective view showing the construction of a caster and a slide member, which are important parts of the present invention;

[20] FlG. 8 is a sectional view showing the operation of the slide member, which is an important part of the present invention; and

[21] FlG. 9 is a plan sectional view showing another embodiment of a caster.

[22]

Mode for the Invention

[23] Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[24] FlG. 1 is an exploded perspective view showing the construction of a skateboard, according to the present invention, and FlG. 2 is a sectional view showing the construction of the skateboard, according to the present invention. As shown in the drawings, the skateboard of the present invention includes a front board section 10, a rear board section 20, a coupling member 40, casters 30, guide parts 50, and slide members 60. The coupling member 40 couples the front and rear board sections 10 and

20 to each other in such a way that they are spaced apart from each other, and comprises an elastic material such that the coupling member 40 is elastically restored when it is twisted or bent. The casters 30 are attached to the bottoms of the two board sections 10 and 20.

[25] Each of the front and rear board sections 10 and 20 includes a cover 10a or 20a, which provides a good appearance, and a main body 10b or 20b.

[26] The main body 10b or 20b includes a holder 11 or 21 which is integrally provided on the lower portion of the main body 10b or 20b and has a space therein, a key groove 14 or 24 which is provided on the upper portion of the main body 10b or 20b, and a position adjusting hole 12 or 22, which is formed in the bottom of the main body 10b or 20b.

[27] The coupling member 40 is made of a synthetic resin material so that it has elastic force. Locking protrusions 41 are provided on opposite ends of the coupling member 40, and are fitted into cross-shaped locking holes 11a and 21a, which are formed in the holders 11 and 21, as shown in FIG. 3, thus preventing the rotation of the coupling member 40. In order to reinforce the elastic force, a flute 42 is formed in the coupling member 40 in a lengthwise direction thereof. Key grooves 43 are formed in the coupling member 40 to correspond to the positions of the key grooves 14 and 24 in the board sections, thus communicating with the key grooves 14 and 24.

[28] Meanwhile, as shown in FIG. 4, inclined surfaces may be formed in the bottoms of the holders 11 and 21 and formed on the lower portions of the opposite ends of the coupling member 40. As shown in FIGS. 5 and 6, iron cores 44 may be embedded in the coupling member 40.

[29] A protective pipe 80 is mounted to the outer portion of the coupling member 40 so as to prevent the coupling member 40 from being broken or damaged. Keys 70 are inserted into the key grooves 14, 24, and 43 of the front board section 10, the rear board section 20, and the coupling member 40, thus allowing the board sections 10 and 20 to be easily coupled to or separated from the coupling member 40.

[30] The guide parts 50 may be integrated with the front board section 10 and the rear board section 20. However, as shown in FIGS. 1 to 7, the guide parts 50 may be manufactured separately from the front and rear board sections 10 and 20 in such a way as to be easily attached to or detached from the board sections 10 and 20. Each guide part 50 includes locking projections 51 which are integrally provided on the upper surface of a rod 52 of the guide part 50, and pass through holes 15 or 25 of each board section 10 or 20. A slide groove 53 is formed in the sidewall of each guide part 50, so that one side of a block 31 of each caster 30 is fitted into the slide groove 53.

[31] Each slide member 60 is mounted to a rotating shaft 34 of each of the casters 30, which are mounted to the bottoms of the front and rear board sections 10 and 20, and is

inserted into the position adjusting hole 12 or 22 to be stopped at ends of the hole 12 or 22. As shown in FlG. 7, each slide member 60 has a body. A hole 61 is formed in the center of the body, and a slide part 61 is integrally provided on the lower portion of the body. The hole 61 has on an inner surface thereof a threaded part to engage with the rotating shaft 34 of the corresponding caster 30. Wings 63 are provided on both sides of the body. Serrated parts 63a are formed on the bottoms of the wings 63 to correspond to serrated parts 12a or 22a which are formed around the position adjusting hole 12 or 22.

[32] Each of the casters 30 includes a bracket 32 which rotatably supports a wheel 33 that is mounted to the bottom of the front or rear board section 10 or 20 and moves the skateboard, a caster body which holds the bracket 32, and the rotating shaft 34, which rotatably supports the caster body.

[33] Meanwhile, as shown in FIG. 9, a stopper 34a is provided on the upper surface of the bracket 32 which constitutes each caster 30, thus allowing the bracket 32 to be rotated within the angular range of 180°.

[34] The operational effect of the present invention, which is constructed as described above, is as follows. After one foot is placed on the front board section 10, the other foot pushes off in a desired direction and is then placed on the rear board section 20. At this time, propulsion force is generated.

[35] However, such pushing with the foot is not the continuous source of propulsion force for the skateboard. Thus, the front board section 10 and the rear board section 20 are oscillated to the left or the right. At this time, the coupling member 40 conducts a bending motion and a twisting motion.

[36] The bending motion and the twisting motion become the primary energy source for moving the skateboard forwards. A rider's weight becomes the secondary energy source.

[37] The method of using the primary energy source to generate the propulsion force is as follows. That is, since the pushing with the foot is not the continuous source of propulsion force for the skateboard, a rider oscillates the skateboard leftwards or rightwards. At this time, the coupling member 40 conducts the bending motion and the twisting motion. That is, the oscillation of the skateboard leads to the swiveling motion of the coupling member 40, that is, the twisting motion thereof.

[38] The process of transmitting the twisting motion is as follows. As shown in FIG. 3, the locking protrusions 41 provided on the opposite ends of the coupling member 40 are inserted into the locking holes 11a and 21a formed in the holders 11 and 21, so that reliable transmission of force is ensured compared to a conventional bolt coupling structure. Moreover, as shown in FIG. 4, if the inclined surfaces are formed on the bottoms in the holders 11 and 21 and are formed on the lower portion of the coupling

member 40, the reliable transmission of force is realized, and slippage between the board sections and the coupling member is prevented. [39] Further, the flute 42 is provided on the middle portion of the coupling member 40 in the lengthwise direction thereof. The coupling member 40 having the flute 42 usually has higher elastic force than a rod or plate, the interior of which is filled, although the elastic force varies according to the material of the coupling member 40. [40] Meanwhile, since the iron cores 44 are embedded in the coupling member 40, as shown in FIGS. 5 and 6, the durability of the coupling member 40, which is made of raw rubber or urethane and becomes twisted after use for a lengthy period of time, is increased. [41] The method of using a rider's weight as the secondary energy source to generate propulsion force is as follows. That is, each of the casters 30, which are attached to the bottoms of the front and rear board sections 10 and 20, is eccentric from an axial line and thus at an angle relative to the axial line, and thus the skateboard has orientation.

The rider's weight is loaded alternately on the front board section 10 and the rear board section 20 using both legs, thus pushing the wheels 33. [42] For example, the twisting motion using the elastic force of the coupling member 40 becomes energy, thus aiding in propelling the wheels 33. [43] Moreover, the rider's weight acts on the eccentric wheels 33, so that propulsion force is maximized and the skateboard is steered as desired. [44] The bending motion occurs between the front board section 10 and the rear board section 20, for example, it occurs when the frictional force of the rear board section 20 is smaller than that of the front board section 10. [45] Thus, as the rider enjoys riding the skateboard, the suppleness of his/her body is increased, the effect of aerobic exercise is obtained, and the effect of training the body is achieved. Further, it becomes possible to use the skateboard without pushing on the ground with the foot. [46] Meanwhile, the positions of the casters 30 must be adjusted according to the body size of a rider, because his or her weight efficiently acts on the casters 30 as the energy source for generating secondary propulsion force, and thus the propulsion force can be easily obtained. [47] If the rider's center of gravity is located ahead of the center of the casters 30 or far from the casters 30, it is impossible to efficiently obtain propulsion force. [48] The position of the casters 30, which are mounted to the bottoms of the front board section 10 and the rear board section 20, and the interval therebetween are adjusted as follows. As shown in FIG. 8, each rotating shaft 34, having on one end thereof a threaded part, is rotated to be loosened from the threaded part of the corresponding slide member 60.

[49] Thereby, the coupling of the bottom around the position adjusting hole 12 or 22 with the serrated parts 63a formed on the bottoms of both wings 63 of each slide member 60 is released, so that the slide member 60 becomes movable.

[50] Thus, even in the state in which the casters 30 are not removed from the position adjusting holes 12 and 22, the rider can move the casters 30 such that the position thereof is suitable for his or her body. Afterwards, each rotating shaft 34 is rotated again so that one end thereof engages with the hole 61 of the corresponding slide member 60.

[51] Since the slide part 62 is guided while being inserted into each position adjusting hole 12 or 22, each slide member 60 is not undesirably removed, but is easily movable. As shown in FIGS. 2, 7, and 8, when each caster 30 is moved, the block 31 of the caster 30 moves along the slide grooves 53 of the guide parts 50, which are secured by the locking projections 51 of the rods 52, which pass through the holes 15 and 25 formed in the bottoms of the board sections 10 and 20. Hence, the undesirable movement and removal of each caster 30 are prevented, so that the position of the caster 30 is easily adjusted.

[52] The parts of the skateboard are disassembled from each other as follows. That is, after the covers 10a and 20a of the front and rear board sections 10 and 20 are opened, the keys 70 are removed from the key grooves 14 and 24. Thereby, the coupling member 40 is easily separated from the holders 11 and 21. The assembly of the parts is conducted in the reverse order. Industrial Applicability

[53] As described above, the present invention provides a skateboard, in which the elasticity of a coupling member is improved in order to increase the propulsion force, separate front and rear board sections are easily coupled to or separated from the coupling member using keys, and position-adjustable casters are provided on the bottoms of the front and rear board sections, thus being capable of adjusting the distance between wheels according to a rider's body condition.

[54]