Patent Publication Number: US-8118319-B2

Title: Twisted structure for a skateboard

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a twisted structure for a skateboard, particularly to the twisted structure having an elastic band enabling a first board member to pivotally twist relative to a second board member. 
     2. Description of Related Art 
     The extreme sports become more popular all over the world. People who are enthusiastic about the sports and are adventurous are all fond of the extreme sports. The players can also keep fit and improve the physical strength when doing the extreme sports. The extreme sports include skiing, skating, surfing, skydiving, skateboarding, rock climbing, etc. Especially, the snakeboarding is a kind of the skateboarding and has recently increased in popularity. 
     A conventional snakeboard usually comprises two footplates which are connected with each other. Two wheels are respectively attached to a bottom of the two footplates. The player of the snakeboarding stands with one foot in each footplate of a snakeboard. The snakeboard is propelled by shifting the user&#39;s body weight in different directions. Therefore, the player does not need to step on the ground to make the snakeboard moving. 
     However, the power and speed of the snakeboard is only controlled by continuously shifting the player&#39;s body weight and the feet positions. It is energy consuming and easy to cause the player&#39;s muscle aching. Moreover, the player may lose his balance to fall down from the snakeboard because the player frequently shifts his body weight and gets tired. 
     The present invention has arisen to mitigate and/or obviate the disadvantages of the conventional casing system. 
     SUMMARY OF THE INVENTION 
     Accordingly, the main object of the present invention is to provide an improved twisted structure for a skateboard which is able to save a user&#39;s energy and reduce the user&#39;s muscular aches. 
     To achieve the above objectives, the present invention provides a twisted structure for a skateboard comprising a first board member and a second board member connected to the first board member. The first board member comprises a first upper board and a first lower board overlappingly connected with each other. The first board member has a first pivot hole axially laterally defined therein and located between the first upper board and the first lower board. The first pivot hole has at least one first flange annularly formed on an inner periphery thereof. The first board member has a first groove defined therein and extending therearound. The first board member has a first through hole defined therein and extending through the first upper board and the first lower board. The first board member has two first curved recesses respectively defined in two opposite sides thereof. 
     The second board member comprises a second upper board and a second lower board overlappingly connected with each other. The second board member has a second pivot hole axially laterally defined therein and located between the second upper board and the second lower board. The second pivot hole has at least one second flange annularly formed on an inner periphery thereof. The second board member has a second groove defined therein and extending therearound. The second board member has a second through hole defined therein and extending through the second upper board and the second lower board. The second board member has two second curved recesses respectively defined in two opposite sides thereof. 
     A pivot shaft is pivotally connected with the first board member and the second board member. The pivot shaft has two ends and a connecting portion which is formed thereon and located between the two ends thereof. Each end of the pivot shaft has at least one annular flute defined in an outer periphery thereof. The two ends of the pivot shaft are respectively and pivotally received in the first pivot hole in the first board member and the second pivot hole in the second board member. The connecting portion of the pivot shaft is located between the first board member and the second board member. The at least one first flange and the at least one second flange are respectively engaged with the at least one annular flutes of the two ends of the pivot shaft, such that the first board member is able to be axially twisted or rotated relative to the second board member about the pivot shaft. 
     An elastic band is elastically received in the first groove and the second groove. The elastic band encloses the first board member and the second board member for connecting the first board member with the second board member. The elastic band is partially exposed at the two first curved recesses of the first board member and the two second recesses of the second board member. The elastic band provides a resilient force to limit a twisting movement of the first board member and the second board member for restoring the first board member and the second board member in an initial position. 
     When a user steps on the first board member and the second board member, the first board member and the second board member are axially twisted relative to the pivot shaft by the user&#39;s feet. The elastic band is stretched by the twisting movement of the first board member and the second board member. The elastic band provides the resilient force to restore the first board member and the second board member in an initial position, such that a skateboard is propelled to stably move, steer, and brake. Accordingly, the operation of the skateboard is energy-saved and reduces the user&#39;s muscular aches. 
     In accordance with a second aspect of the present invention, the first board member is formed by the first upper board and the first lower board. The first board member has a first groove defined therein and extending therearound. The first board member has a first through hole defined therein and extending through the first upper board and the first lower board. The first board member has two first curved recesses respectively defined in two opposite sides thereof. 
     The second board member is formed by the second upper board and the second lower board. The second board member has a second groove defined therein and extending therearound. The second board member has a second through hole defined therein and extending through the second upper board and the second lower board. The second board member has two second curved recesses respectively defined in two opposite sides thereof. 
     The elastic band is elastically received in the first groove and the second groove. The elastic band encloses the first board member and the second board member for connecting the first board member with the second board member. The elastic band is partially exposed at the two first curved recesses of the first board member and the two second recesses of the second board member. 
     Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a preferred embodiment of a twisted structure for a skateboard in accordance with the present invention; 
         FIG. 2  is an assembled perspective view of the preferred embodiment of the twisted structure for a skateboard in accordance with the present invention; 
         FIG. 3  is a partially cross-sectional side view of the preferred embodiment of the twisted structure for a skateboard in accordance with the present invention; 
         FIG. 4  is an operational perspective view of the preferred embodiment of the twisted structure for a skateboard in accordance with the present invention; 
         FIG. 5  is an assembled perspective view of a second embodiment of the twisted structure for a skateboard in accordance with the present invention; and 
         FIG. 6  is an operational perspective view of the second embodiment of the twisted structure for a skateboard in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings and initially to  FIGS. 1-4 , a twisted structure for a skateboard in accordance with the present invention comprises a first board member  20  and a second board member  30  coaxially connected to the first board member  20 . The first board member  20  comprises a first upper board  21  and a first lower board  22  overlappingly connected with each other. The first board member  20  has a first pivot hole  24  axially laterally defined therein and located between the first upper board  21  and the first lower board  22 . The first pivot hole  24  has two first flanges  25  spacedly and annularly formed on an inner periphery thereof. The first board member  20  has a first groove  26  defined therein and extending therearound. The first board member  20  has a first through hole  23  vertically defined therein and extending through the first upper board  21  and the first lower board  22 . The first board member  20  has two first curved recesses  27  respectively and laterally defined in two opposite lateral sides thereof. 
     The second board member  30  comprises a second upper board  31  and a second lower board  32  overlappingly connected with each other. The second board member  30  has a second pivot hole  34  axially laterally defined therein and located between the second upper board  31  and the second lower board  32 . The second pivot hole  34  has two second flanges  35  spacedly and annularly formed on an inner periphery thereof. The second board member  30  has a second groove  36  defined therein and extending therearound. The second board member  30  has a second through hole  33  vertically defined therein and extending through the second upper board  31  and the second lower board  32 . The second board member  30  has two second curved recesses  37  respectively and laterally defined in two opposite lateral sides thereof. 
     A pivot shaft  10  is pivotally connected with the first board member  20  and the second board member  30 . The pivot shaft  10  has two ends and a connecting portion  12  formed thereon. The connecting portion  12  is in a rectangular shape and is located between the two ends of the pivot shaft  10 . Each end of the pivot shaft  10  has two annular flutes  11  spacedly defined in an outer periphery thereof. The two ends of the pivot shaft  10  are respectively and pivotally received in the first pivot hole  24  in the first board member  20  and the second pivot hole  34  in the second board member  30 . The connecting portion  12  of the pivot shaft  10  is located between the first board member  20  and the second board member  30 . The two first flanges  25  and the two second flanges  35  are respectively and correspondingly engaged with the four annular flutes  11  of the two ends of the pivot shaft  10  for preventing the first board member  20  and the second board member  30  from detaching. Accordingly, the first board member  20  is able to be axially twisted or rotated relative to the second board member  30  about the pivot shaft  10 . 
     An elastic band  40  is stretchably received in the first groove  26  and the second groove  36 . The elastic band  40  encloses around the first board member  20  and the second board member  30  for connecting the first board member  20  with the second board member  30 . The elastic band  40  is exposed at the two first curved recesses  27  of the first board member  20  and the two second recesses  37  of the second board member  30 . The elastic band  40  is exposed between the first board member  20  and the second board member  30 . The elastic band  40  provides a resilient force to limit a twisting movement of the first board member  20  and the second board member  30  for restoring the first board member  20  and the second board member  30  in an initial position. The elastic band  40  is made of a light emitting material which contains phosphors. 
     Two wheels  50  are respectively mounted to a bottom of the first lower board  22  and a bottom of the second lower board  32 , such that the two wheels  50  enable the skateboard to move. 
     When a user steps on the first board member  20  and the second board member  30 , the first board member  20  and the second board member  30  are axially twisted or rotated relative to the pivot shaft  10  by shifting the user&#39;s body weight. The elastic band  40  is stretched by the twisting movement of the first board member  20  and the second board member  30 . The elastic band  40  provides the resilient force to restore the first board member  20  and the second board member  30  in an initial position. The movement of the first board member  20  and the second board member  30  enables the two wheels  50  to roll, such that the skateboard is propelled to stably move forward or brake. 
     With reference to  FIGS. 5-6 , these show a second embodiment of the twisted structure for a skateboard in accordance with the present invention. The elements and effects of the second embodiment which are the same with the preferred embodiment are not described, only the differences are described. In this embodiment, the first board member  20  is formed by the first upper board  21  and the first lower board  22 . The first board member  20  has a first groove  26  (shown in  FIG. 1 ) defined therein and extending therearound. The first board member  20  has a first through hole  23  defined therein and vertically extending through the first upper board  21  and the first lower board  22 . The first board member  20  has two first curved recesses  27  respectively defined in two opposite sides thereof. 
     The second board member  30  is formed by the second upper board  31  and the second lower board  32 . The second board member  30  has a second groove  36  (shown in  FIG. 1 ) defined therein and extending therearound. The second board member  30  has a second through hole  33  defined therein and vertically extending through the second upper board  31  and the second lower board  32 . The second board member  30  has two second curved recesses  37  respectively defined in two opposite sides thereof. 
     The elastic band  40  is elastically received in the first groove  26  and the second groove  36 . The elastic band  40  encloses around the first board member  20  and the second board member  30 , such that the first board member  20  is spacedly connected with the second board member  30 . The elastic band  40  is partially exposed at the two first curved recesses  27  in the first board member  20  and the two second curved recesses  37  in the second board member  30 . 
     Accordingly, there are several advantages to the twisted structure for a skateboard in accordance with the present invention. Firstly, during assembling, the first board member  20  is assembled from the first upper board  21  and the first lower board  22 , and the second board member  30  is assembled from the second upper board  31  and the second lower board  32 . The pivot shaft  10  and the elastic band  40  are easily placed into the first board member  20  and the second board member  30 . It increases the efficiency of the assembling process. Secondly, when the elastic band  40  is illuminated by the visible light and the electromagnetic wave, the phosphors of the elastic band  40  are actuated to continuously emit light. Therefore, the emitted light of the elastic band  40  provides a warning effect when the skateboard is used in the dark or dusky places. Thirdly, the user is easily grasped the skateboard through the first through hole  23 , the second through hole  33 , the two first curved recesses  27 , and the two second curved recesses  37 . Or the user can attach a rope or a chain through the first through hole  23 , the second through hole  33 , the two first curved recesses  27 , and the two second curved recesses  37 , such that the user is able to conveniently carry the skateboard. Furthermore, due to the resilient force provided by the elastic band  40 , the operation of the skateboard is energy-saved and reduces the user&#39;s muscular aches. 
     Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.