Abstract:
A knock-down quarter pipe for bikers, skateboarders and in-line skaters has a base, and a plurality of legs extending up from the base, the legs having lower ends lying in a common plane. A deck is supported by the legs at a selected elevation above the base, the deck having front and rear edges and a surface extending between those edges that is substantially parallel to the plane. A ramp extends from the front edge of the deck down to the plane, that ramp having a lower leading edge that is located in that plane and spaced in front of a base. Preferably, the base and at least the lower end portion of the ramp may be filed with a fluid medium to add weight to and lower the center of gravity of the quarter pipe. Preferably also, a rigid coping rail is located between the front edge of the deck and the ramp which can function as a grind rail.

Description:
RELATED APPLICATIONS 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     This invention relates to obstacles used by skateboarders, bikers and in-line skaters to enhance their individual ability and enjoyment. It relates more particularly to an obstacle referred to as a quarter pipe. 
     FIELD OF THE INVENTION 
     A quarter pipe, as the name suggests, is an obstruction which has a shape corresponding to one quadrant of a cylinder with an entry edge of the cylinder being located next to the ground. The quarter pipe thus constitutes a ramp which redirects a rider entering the ramp upward approximately 90° to a platform, cornice or rail which allows the rider to reverse direction and roll down the quarter pipe to ground level. 
     Usually such quarter pipes are relatively massive unitary obstacles made of reinforced concrete or the like and because of their cost, they are usually only found in parks and other public spaces. They are not designed for home use. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a quarter pipe which can be sold in a knock-down condition and assembled by the average purchaser for home use. 
     Another object of the invention is to provide such a quarter pipe which is easy to assemble and, when assembled, is rugged enough to withstand prolonged use by skateboarders, bikers and in-line skaters. 
     A further object of the invention is to provide a quarter pipe which, although portable, is quite stable in use. 
     Yet another object of the invention is to provide a knock-down quarter pipe composed of a minimum number of parts which can be assembled in a minimum amount of time without requiring any tools. 
     Other objects of the invention will, in part, be obvious and will, in part, appear hereinafter. 
     The invention accordingly comprises the features of construction, combination of elements and arrangement of parts which will be exemplified in the following detailed description and the scope of the invention will be indicated in the claims. 
     Briefly, our quarter pipe comprises a base supported by a plurality of legs which extend up to a raised platform or deck. A curved ramp extends from an edge of the deck down to the ground in front of the base, the ramp being composed of a wedge-like entry section adjacent to the ground and one or more concavely curved ramp sections which extend from the entry section up to the deck. Preferably, the upper end of the ramp sections transition to the deck by way of a coping rail which may function as a grind rail for skateboarders and skaters using the quarter pipe. Preferably also, a handrail extends up from the rear edge of the deck opposite the ramp sections as a safety precaution. Also, in a preferred embodiment of the invention, the aforesaid base and entry sections are designed to be filled with a relatively heavy fluid medium such as water or sand in order to increase the weight of the apparatus and lower its center of gravity. This helps to stabilize the quarter pipe and prevent it from moving around when in use. 
     As we shall see, the quarter pipe is composed of a minimum number of parts which are relatively inexpensive to make in quantity and which can be assembled very easily using only a screwdriver when the unit is first set up and no tools thereafter. Therefor, it can be sold in a knock-down condition for assembly by the purchaser. Furthermore, when not in use, it can be disassembled without any tools and stored in a minimum amount of space. Therefor it should prove to be a popular and marketable toy product. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in connection with the accompanying drawings, in which: 
     FIG. 1 is a right front perspective view of a quarter pipe incorporating invention; 
     FIG. 2 is a rear elevational view thereof; 
     FIG. 3 is an exploded perspective view, with parts broken away, showing the components of the FIG. 1 quarter pipe in greater detail; 
     FIG. 4 is a sectional view taken along line  4 — 4  of FIG. 1; 
     FIG. 4A is a similar view showing the same parts disassembled; 
     FIG. 5 is a sectional view, on a larger scale, taken along line  5 — 5  of FIG. 1, and 
     FIG. 5A is a sectional view taken along line  5 A— 5 A of FIG.  5 . 
     FIG. 6 is an elevational view showing the components of FIG. 1 quarter pipe stacked in a package. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. 1 and 2 of the drawings, our quarter pipe, shown generally at  8 , comprises a generally rectangular base  10  in the form of a water tank having a rear wall  10   a  and a front wall  10   b . The base is supported at its corners by a pair of tubular rear legs  12  and a pair of tubular front legs  14 . Those legs extend up to a generally rectangular raised deck or platform  16  which is spaced appreciably above base  10  and has a rear wall  16   a , a front wall  16   b  and opposite end walls  16   c  and  16   d . As best seen in FIG. 2, the front legs  14  are more or less vertical, while the rear legs  12  are toed in so that they may be slightly longer than legs  14  in order to maintain deck  16  in a horizontal plane. 
     As shown in FIG. 1, an inverted, generally U-shaped tubular handrail  18  extends up from deck  16  adjacent the rear wall  16   a  thereof. Preferably, the legs of the handrail  18  are aligned with rear legs  12 . Preferably also, the handrail is composed of two mirror-image L-shaped sections  18   a ,  18   a  connected at their upper ends by a short tube  19  telescoped into the opposing ends of the two sections. The sections may be clamped together around the tube  19  by a clip  20  of the type described in application Ser. No. 09/991,811, the contents of which are hereby incorporated by reference herein. 
     Still referring to FIGS. 1 and 2, deck  16  supports at its front edge  16   b  the upper end of a ramp shown generally at  22 . The ramp has concave curvature so that its lower end rests on the ground well in front of base  10 . As best seen in FIG. 1, ramp  22  is preferably composed of at least two identical arcuate ramp sections  22   a ,  22   a  arranged side by side, and a generally wedge-shaped entry section  22   b  which supports the lower ends of sections  22   a  and extends down to the ground so that the totality forms a concavely curved ramp surface which presents a sharp leading edge at ground level. 
     Preferably also, the transition of the upper end of ramp  22  to deck  16  is provided by means of a generally horizontal, rigid, tubular coping rail  24  which extends the full width of ramp  22  and may be function as a grind rail. The diameter of the coping rail is such that the opposing ends of the deck and ramp upper surfaces are tangent to the coping rail. This enables a skateboarder, for example, while rolling up ramp  22  to deck  16  to pause on, or roll along, rail  24  in order to reverse direction and roll down ramp  22  to the ground. On the other hand, a rider riding up ramp  22  may roll over the coping rail  22  onto deck  16  in order to rest or execute a reversal on the deck. The handrail  18  is provided to assist in that respect and for safety reasons. Also to prevent overtravel of skate wheels, a raised rib  25  may be provided adjacent the rear wall  16   a  of the deck, the rib extending at least between the legs of handrail  18 . 
     As we shall see, the components of the quarter pipe are dimensioned and spaced so that when assembled, the apparatus is quite stable while in use. To add to this stability, the base  10  and entry section  22   b  are preferably weighted to increase the overall mass of the apparatus and to lower its center of gravity. This assures that when a rider rolls up ramp  22  to deck  16 , the weight and momentum of the rider will not cause the apparatus to tip over, tilt or shift relative to the ground. 
     As shown in FIGS. 1 and 2, the illustrated base  10  is generally rectangular and molded of a suitable strong, weather-resistant plastic such as polyethylene. Typically its dimensions are 4 ft. by 2 ft. by 4 in. Preferably, the base is solid or rigidified at the corners so that through holes  32  may be provided to accommodate the legs  12  and  14 . However, the remainder of the base  10  is preferably hollow to provide a fluid tight cavity  34  which may be filled with a fluid such as water or sand in order to increase the weight of the base. As best seen in FIG. 2, one or more holes  36  may be provided in the top wall  10   a  of base  10  adjacent to the center line thereof to fill up, and drain the fluid from, cavity  34 . When the base is filled with fluid, these holes may be closed by suitable plugs  38 . 
     When assembling legs  12  and  14  to base  10 , the lower ends of the legs are inserted through the corner holes  32  in the base and end caps  40  are secured to the lower ends of the legs so that the corners of the base are supported by the end caps when the end caps rest on the ground or other support surface. Alternatively, the base  10  itself may rest on the ground. 
     Referring to FIGS. 1 to  3 , deck  16  is also a generally rectangular molded plastic article having dimensions slightly smaller than those of base  10 . Typically, the deck  16  is spaced about 3 feet above the ground. However unlike base  10 , deck  16  is not hollow. Rather it has an open bottom and a multiplicity of intersecting ribs  42  extend down from the top wall of the deck between the side and end walls thereof to form a grid structure which makes the deck quite resistant to bending and racking forces. 
     As best seen in FIG. 2, a pair of vertical through holes  44  are provided in deck  16  adjacent to the rear corners thereof directly above the upper ends of rear legs  12 . These holes are smaller than the leg  12  outside diameter but are large enough to slidebly receive the lower ends of the hand rail sections  18   a  which are sized to telescope into the upper ends of legs  12  as shown. The hand rail sections  18   a  may be releasably retained in legs  12  by conventional spring-loaded push buttons  46  mounted in the legs of sections  18   a  and which snap into holes  47  formed in legs  12 . The deck  16  is supported by rigid washers  49  which sit on the upper ends of legs  12  as shown in FIG. 2, the openings in the washers being sized to slidebly receive the legs of the rail sections  18   a.    
     The attachment of the front legs  14  to deck  16  is somewhat different as will be described shortly. Also for reasons that will become apparent, deck  16  is provided at one side with a long key or a lug  48  which projects out laterally from the deck and has an upwardly extending nose  48   a . In addition, an elongated keyhole or notch  50  is provided at the opposite end of deck  16  which is adapted to receive the key  48  of an adjacent deck  16 . This allows the FIG. 1 quarter pipe  8  to be keyed to one or more adjacent similar quarter pipes  8  arranged side by side as shown in phantom in FIG.  1 . 
     Referring to FIG. 3, the front edge  16   b  of deck  16  is formed with a pair of aligned notches  52  spaced apart along that edge and separated by a relatively long shelf  54  which projects out from deck wall  16   b . The shelf  54  has an upper surface  54   a  which is generally semi-cylindrical with the same curvature as that of coping rail  24 . In addition, a pair of side shelves  56  project out from deck wall  16   b  adjacent to the outboard ends of the notches  52 . Shelves  56  are set in from the opposite ends of wall  16   b  enough to provide clearance of the upper ends of the front legs  14 . Like shelf  54 , shelves  56  have semi-cylindrical upper surfaces  56   a  which are co-linear with surface  54   a.    
     As shown in FIG. 3, the coping rail  24  is provided with a pair of downwardly extending tubular stubs  24   a  which are sized and spaced apart to telescope into the upper ends of legs  14  when the coping rail is seated on shelves  54  and  56 . When so seated, the legs  14  may be releasably secured to the coping rail  24  by spring-loaded push buttons  58  projecting from rail stubs  24   a  and which are adapted to snap into holes  59  in legs  14 . The washers  60  which sit on the upper end of legs  14  support the front corners of deck  16  in the same manner of the washers  49  over rear legs  12 . 
     Preferably, as part of the initial set up of the quarter pipe, the coping rail  24  is permanently attached to shelves  54 ,  56  by suitable threaded fasteners  62  (FIG. 3) inserted from below the shelves and threaded into the rail. This leaves openings  64  between the rail and the rear walls of notches  52  as shown in FIGS. 4 and 4A. Preferably also, the open ends of rail  24  are closed by suitable end plugs  70 . 
     Referring to FIGS. 2 and 3, each ramp section  22   a  has a curved top wall  72   a  and a pair of opposite side walls  72   b  and  72   c  which extend down from wall  72   a . As best seen in FIG. 2, a multiplicity of ribs  74  extend down from the underside of wall  72   a  and form a rectangular grid between the side walls  72   b  and  72   c . Typically, each section is a molded article of the same material as base  10  and is about 4 ft. long and 2 ft. wide. A series of wedge-shaped keys  76  project out from the side wall  72   b  of each ramp section  22   a . These keys are adapted to key into a corresponding series of wedge-shaped keyholes  78  in each ramp section wall  72   c  to prevent movement of the two sections away from one another, i.e. in a horizontal manner. 
     Referring to FIGS. 3,  4  and  6 , a curved tongue  82  projects from the upper end of each ramp section  22   a . The tongue  82  is set in from the opposite sides of the ramp section and its length is slightly less than the length of the notches  52  in deck  16 . The upper surface  82   a  of tongue  82  has essentially the same curvature as the shelf surfaces  54   a ,  56   a . Thus after the coping rail  24  has been permanently anchored to deck  16  as described above, the ramp sections  22   a  may be attached to the deck by inserting the tongues  82  of the ramp sections into the openings  64  behind rail  24  from below as shown in FIG.  4  and rotating the sections clockwise in that figure so that the tongue surfaces engage under and behind rail  24  as shown in FIG.  4 . Thus when the ramp sections  22   a  are in their downwardly sloping positions shown in FIG. 4, the tongues  82  of those sections are securely locked to deck  16 . However, those connections still allow the sections to pivot about the rail to some extent so that the legs  12 ,  14 , on the one hand, and ramp entry section  22   b , on the other, can rest stably on somewhat uneven ground. In other words, the connections allow automatic leveling of the quarter pipe on uneven ground. The connections also allow the ramp sections to be detached from the deck  16  simply by swinging the sections  22  up to the position shown in FIG.  4 A and withdrawing the tongues  82  from openings  64 ; no tools are required for such detachment or subsequent reassembly. 
     As shown in FIGS. 1 and 3, in order to secure the lower end of each ramp section  22   a  to entry section  22   b , the top wall  72   a  of each ramp section is formed with a relatively large counter sunk hole  86  having diametrically opposite, laterally extending notches  86   a  in the edge of the hole. As will be described shortly, the hole  86  is adapted to receive a locking cap  88  which locks the lower end of each ramp section  22   a  to the entry section  22   b.    
     Referring now to FIGS. 3 and 5, entry section  22   b  is preferably made of the same material as base  10  and deck  16  and has more or less the same length and width dimensions as deck  16 . The entry section has a gently concavely curved top wall  92   a , a pair of opposite wedge-shaped sidewalls  92   b  and  92   c , a rear wall  92   d  and a bottom wall  92   e  which together define an internal fluid-tight cavity  94 . As best seen in FIG. 1, the entry section  22   b  provides a sharp leading edge transition from entry section  22  to the ground or other support surface. 
     An elongated key or lug  102  projects laterally from side wall  92   b  adjacent to the bottom of the entry section. Also, a key hole  104  is provided in the opposite side wall  92   c  of entry section  22   b  which key hole is arranged and adapted to receive the key  102  of an adjacent quarter pipe  8  so that two or more of the FIG. 1 quarter pipes  8  can be placed side by side and locked together. In other words the key holes  50 ,  78  and  104  of the quarter pipe  8  depicted in FIG. 1 are adapted to receive the keys  48 ,  76  and  102  of the similar quarter pipe shown in phantom in FIG.  1 . Thus, a series of quarter pipes may be locked together to form an elongated version of the quarter pipe shown in solid lines in FIG.  1 . 
     Referring to FIGS. 3 and 5, the upper rear edge segment of entry section  22   b  is formed with a pair of laterally spaced apart shelves  110  recessed or stepped down from the upper end of top wall  92   a , the shelves being separated by a vertical notch  112 . Each shelf  110  has an inclined top wall with a discoid promontory  114  centered in the shelf. Furthermore, each promontory is formed with a relatively large locking hole  116  centered in the promontory and which opens into cavity  94 . A pair of diametrically opposite notches or keyholes  116   a  are present at the edge of hole  116 , the notches being aligned with the short axis of the entry section. 
     The entry section  22   b  is designed so that when the lower end segments of the ramp sections  22   a  are seated side by side on shelves  110 , the opposing, keyed-together side walls  72   b  and  72   c  of the two ramp sections  22   a  extend down into the notch  112  in entry section  22   b  and the holes  86  and notches  81   a  of the two ramp sections are aligned with the holes  116  and notches  116   a  in the entry section promontories  114 . This allows each locking cap  88  to be inserted down through the corresponding aligned holes  86  and  116 . As best seen in FIG. 5, each cap  88  includes a head  88   a , and a depending neck  88   b  having at its free end a pair of diametrically opposite keys or ears  88   c  which are sized to be received in the notches  86   a  and  116   a  when the ears are aligned with the notches. Then by pressing down and turning the cap  88  about 90°, the cap  88  firmly locks each ramp section  22   a  to the entry section  22   b  as shown in FIGS. 1 and 5. Preferably, a pair of aligned slots  117  are provided in each cap head  88   a  so that the caps may be turned using coins inserted into the slots; that is, no tools are required. 
     Referring to FIG. 5, like base  10 , entry section  22   b , i.e. its cavity  94 , may be filled with water, sand or the like by way of the locking holes  116 . Preferably, gaskets or seal rings  120  are provided on looking caps  88  under their heads  88   a  so that holes  116  are sealed when the locking caps  88  are locked in place as shown in FIGS. 1 and 5. 
     Referring to FIG. 6, all of the above-described components of the FIG. 1 quarter pipe  8  may be stacked and shipped along with a bag B containing miscellaneous parts such as the end caps  40 , fasteners  62 , plugs  70 , washers  49 ,  60 , etc. in a relatively small volume package or carton P. A customer may purchase the quarter pipe in that knock-down condition and assemble it in a minimum amount of time, attaching the various components of the quarter pipe in the manner described above. After assembling the quarter pipe, the user may fill the base  10  and the entry section  22   b  with a fluid to lower the unit&#39;s center of gravity and increase its mass so that the unit will not tilt or shift relative to the ground when skaters, skateboarders and the like ride up and down the quarter pipe  8 . As noted above, a plurality of the quarter pipes  8  can be connected together side by side in order to increase the overall length of the obstacle so that the children using the obstacle can perform more intricate acrobatic feats. 
     It will thus be seen that the objects set forth above among those made apparent from the preceding description, are efficiently attained. 
     Also, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanied drawings shall be interpreted as illustrative and not in a limiting sense. 
     It should also be understood that the following claims are intended to cover all of the generic and specific features of the invention described herein.