Abstract:
A push-up trainer having a base and a pair of handgrip assemblies. The handgrip assemblies are each slidably mounted to the base, allowing for lateral movement of the handgrips. Each handgrip assembly allows for rotation of each handgrip around a vertical axis and around its horizontal lengthwise axis. Each of the sliding and rotational motions may selectively be allowed or locked out using a spring biased pin.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is a pushup trainer having slidably and rotatably mounted handgrips, allowing the user to increase the benefits of his workout by forcing the user to control the rotation and lateral movement of the handgrips while performing pushups. 
     2. Description of the Related Art 
     The benefits of performing pushups for increased upper body development are well known. Pushups are one of the best exercises for strengthening the triceps, pectorals, and deltoids. Unlike weight training, pushups can be performed without the need for a spotter, and place less stress on the joints. 
     Several other inventors have proposed various devices for increasing the benefits of performing pushups. However, no other inventor within the knowledge of the present inventor has proposed a pushup trainer having the advantages of the present invention. Specifically, no other pushup trainer provides a pair of handgrips which can rotate around both horizontal and vertical axes, and which also slide laterally, and which allows each individual rotational or lateral motion to be individually locked out or permitted without affecting the other possible motions. 
     One example of a pushup trainer is U.S. Pat. No. 3,115,338, issued to Katherine and Peter Acs on Dec. 24, 1963. This patent describes a pair of handles having a flat base. The base rests on the floor, while a person performing pushups grips the handles. The handles may have a base with a suction cup, so that the suction cup can attach to a wall, allowing the user to grasp the grip to maintain his balance. A third embodiment has a hook-shaped bolt, allowing the handles to hang from an overhead support for performing pullups. 
     U.S. Pat. No. 4,351,525, issued to William L. Rozenblad on Sept. 28, 1982, describes a pair of wood platforms, each having a non-skid surface on the bottom, and a U-shaped handle on top. The handles may be used in pairs for performing pushups, or only a single handle may be used to provide for a more difficult pushup. 
     U.S. Pat. No. 4,610,448, issued to David L. Hill on Sept. 9, 1986, describes a pushup training device having both handgrips pivotally attached to the same base. The U-shaped bracket supporting the handgrips can rotate around a vertical axis, and the handgrips can rotate around a longitudinal horizontal axis. 
     U.S. Pat. No. 5,205,802, issued to William J. Swisher on Apr. 27, 1993, describes a pushup training device having a single elongated base for a pair of handgrips. The base includes holes positioned at various differences from its vertical center, allowing the handgrips to be positioned at a desired distance from the center. The handgrips can rotate around a vertical axis as the user performs pushups. 
     U.S. Pat. No. 5,226,868, issued to Calvin W. Montgomery on Jul. 13, 1993, describes a pushup training device having a board and two C-shaped handles. The board has holes in various positions for attaching the handles. Only one end of the handles attaches to the board, allowing the handles to rotate around a vertical axis at the attachment point. 
     U.S. Pat. No. 5,607,380, issued to John E. Duty on Mar. 4, 1997, describes a pushup training device having a pair of bases, with each base supporting a gripping bar. The gripping bar may be positioned at various desired angles. An elastic band extends from one handgrip to the other, passing over the back of the neck, to provide a workout for the neck muscles as the user pushes himself up. 
     U.K. Pat. No. 2,270,636, published on Mar. 23, 1994, describes a pushup training device having a board and a pair of U-shaped handles. The board has several sets of holes, allowing the user to position each of the handles in a pair of holes. The user can thereby set the handles a desired distance apart. 
     German Pat. No. 4,229,970, published on Mar. 10, 1994, describes an exercise device. 
     None of the above patents describes a pushup trainer allowing the user to selectively lock out or allow horizontal rotation, vertical rotation, or lateral movement of the handgrips while performing pushups. None of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention as claimed. Thus a push-up trainer solving the aforementioned problems is desired. 
     SUMMARY OF THE INVENTION 
     The present invention is a pushup trainer having a base and a pair of handgrip assemblies. The handgrip assemblies each include a sliding member slidably mounted within the base, a rotating plate rotatably attached to the top of the sliding member, a grip brace extending upward from the rotating plate, and a handgrip rotatably secured between the arms of the brace. 
     The base is an elongated member having a top surface surrounded by a lip to secure the sliding members in place. The top surface is preferably made of material having a low coefficient of friction. The top surface also includes a plurality of holes extending down its length, for engaging a retractable locking pin on each handgrip assembly&#39;s sliding member. The length of the base is sufficient to allow pushups to be performed with a wide variety of arm positions. 
     A pair of grip assemblies are slidably attached to the base, within the lip around the edges of the base. Preferably, the bottom of the sliding members is made from a material having a low coefficient of friction. A locking pin is located within the sliding member. The locking pin is spring-biased in the locked position, wherein its tip is within one of the holes in the base, preventing sliding movement. A preferred and suggested locking pin has a cutout at the bottom edge of a knob at the top surface, with a shelf attached to the base and fitting within this cutout when the pin is in the locked position. Raising the locking pin, and rotating the pin so that the knob&#39;s cutout is not aligned with the shelf will allow the bottom edge of the pin&#39;s knob to rest on the shelf, holding the pin in the unlocked position and allowing sliding movement. 
     A rotating plate is mounted on top of the sliding plate, secured by a vertical shaft acting as the rotational axis. The rotating plate includes a locking pin which is spring-biased in a locked position, wherein the end of the pin fits within one of several holes in the sliding member, preventing rotational movement. Like the sliding member&#39;s locking pin, a preferred and suggested locking pin has a cutout at the bottom edge of a knob at the top surface, with a shelf attached to the base and fitting within this cutout when the pin is in the locked position. Raising the locking pin, and rotating the pin so that the knob&#39;s cutout is not aligned with the shelf will allow the bottom edge of the pin&#39;s knob to rest on the shelf, holding the pin in the unlocked position and allowing sliding movement. 
     A brace having a pair of arms extends upward from the rotating plate, with a handle mounted between the arms. The handle includes a horizontal locking pin which also serves as a rotational axis. One end of the locking pin includes a square knob, fitting within a square hole in one arm and in the handle. The locking pin is spring-biased in the locked position, wherein the square knob is within the square holes, preventing rotation. Pulling the square knob outward and rotating it 45° secures the locking pin in the unlocked position, permitting the handle to rotate. 
     When performing pushups using the present invention, the user must use his muscles to control any sliding or rotational motion which is not locked out by a pin. The user must prevent the handgrips from sliding outward or inward, rotating around a horizontal axis, or rotating around a vertical axis, all while performing a standard pushup. This added requirement increases the number of muscles involved in the workout, thereby exercising and strengthening the additional muscles. The ability to selectively and individually lock out the lateral sliding, vertical rotation, or horizontal rotation of each gripping assembly allows the user to control the amount and type of additional muscular effort will be necessary to perform the pushups. 
     If the user chooses to lock out the rotation of the rotating plate, he may do so with the handle oriented either parallel to the base, corresponding to a palm-down or palm-up pushup position, or perpendicular to the base, corresponding to a palm-inward pushup position. It is well known in the field of exercise that changing the orientation of the hands alters the alignment of the muscles in the arm. With the palms facing downward, the arms are in a position where they can perform a pushing motion most efficiently. With the palms facing inward, the resulting pushup is effective for activity-specific muscular training, and results in an arm motion similar to a karate vertical fist punch. 
     Accordingly, it is a principal object of the invention to provide a pushup trainer having a pair of handgrip assemblies allowing for lateral motion, horizontal rotation, and vertical rotation of the handgrips. 
     It is another object of the invention to provide a pushup trainer allowing the user to selectively allow or lock out the lateral motion, horizontal rotation, or vertical rotation of the handgrips. 
     It is a further object of the invention to provide a pushup trainer which allows the user to choose to control the lateral movement, horizontal rotation, and vertical rotation of the handgrips using muscular strength while performing pushups, thereby increasing the benefits of performing the pushups. 
     Still another object of the invention is to provide a pushup training device having handles which may be oriented so that they are parallel to the base, perpendicular to the base, or any angle therebetween, correspond to the muscle alignment in the arm most closely resembling that which will occur during the user&#39;s athletic endeavors. 
     It is an object of the invention to provide improved elements and arrangements thereof for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes. 
     These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an environmental, perspective view of a push-up trainer according to the present invention. 
     FIG. 2 is a cross sectional view of a push-up trainer according to the present invention. 
     FIG. 3A is a side cross sectional view of a handgrip assembly for a push-up trainer according to the present invention, showing the sliding member and rotating plate secured in place. 
     FIG. 3B is a fragmented, end cross sectional view of the sliding member, showing details of the locking pin in the locked position along line  3 B— 3 B of FIG.  3 A. 
     FIG. 4A is a side cross sectional view of a handgrip assembly for a push-up trainer according to the present invention, showing the sliding member free to slide, and the rotating plate free to rotate. 
     FIG. 4B is a fragmented, end cross sectional view of the sliding member, showing details of the locking pin in the unlocked position along line  4 B— 4 B of FIG.  4 A. 
     FIG. 5 is a side cross sectional view of the handle and handle brace, showing the handle&#39;s locking pin in the locked position. 
     FIG. 6 is a side cross sectional view of the handle and handle brace, showing the handle&#39;s locking pin in the unlocked position. 
    
    
     Similar reference characters denote corresponding features consistently throughout the attached drawings. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention is a pushup trainer. Referring to FIGS. 1 and 2, the pushup trainer  10  has an elongated base  12  and a pair of slidably mounted handgrip assemblies  14 , 16 , slidably mounted within the base. The base includes a flat top surface  18 , preferably having a low coefficient of friction, and a lip,  20 , surrounding the outside of the top surface  18 . The lip  20  extends upward from the edges of the top surface  18 , and then extends inward to lip over the top edges of the sliding members  22  of handgrip assemblies  14 , 16 . The top surface  18  of base  12  includes a row of holes  24  extending linearly between the ends  80  of top surface  18 . 
     Referring to FIGS. 3A,  3 B,  4 A and  4 B, an individual handgrip assembly  14 , 16  is shown. Sliding member  22  forms the bottom of the handgrip assemblies  14 , 16 , with rotating plate  26  secured to sliding member  22  by vertical shaft  28 . Brace  30  is secured to the top of rotating plate  26 . Brace  30  includes arms  32 , 34 , securing handgrip  36  therebetween. 
     Sliding member  22  is slightly elongated in the same direction as the base  12 , with flat sides  82  fitting within lips  20 , thereby securing sliding member  22  to base  12 , and preventing sliding member  22  from rotating with respect to base  12 . Sliding member  22  preferably has a low coefficient of friction, particularly where it contacts the base  12  and any other rotatably contacting surfaces. Sliding member  22  includes locking pin  38   a , which fits within holes  24  in base  12  to prevent sliding member  22  from sliding. Spring  40   a , with its end resting on plate  78   a  near end  48   a  of locking pin  38   a , biases locking pin  38   a  in the locked position. Knob  42   a , on top of locking pin  38   a , can be grasped to retract locking pin  38   a . Knob  42   a  defines cutout  44   a  along its lower edge, corresponding to shelf  46   a , attached to the top surface of sliding member  22 . When pin  38   a  is in the locked position, shelf  46   a  fits within cutout  44   a , and the end  48   a  of pin  38   a  protrudes from the bottom of the sliding member  22 , fitting within one of the holes  24  in base  12 . When pin  38   a  is retracted and rotated, the edge  50   a  of knob  42   a  rests on shelf  46   a , securing pin  38   a  in the unlocked position, wherein end  48   a  of pin  38   a  does not protrude from sliding member  22 , and sliding member  22  is free to slide laterally within housing  12 . Sliding member  22  also includes holes  52  in its top surface, with holes  52  defining a circle around and being equidistant from shaft  28 . 
     Rotating plate  26  is attached to sliding member  22  by shaft  28 . Rotating plate  26  is preferably round, preventing any interference with lips  20  during rotation, and preferably has a low coefficient of friction. Like sliding member  22 , rotating plate  26  includes locking pin  38   b , which fits within holes  52  in sliding member  22  to prevent rotating plate  26  from rotating. Spring  40   b , with its end resting on plate  78   b  near end  48   b  of locking pin  38   b , biases locking pin  38   b  in the locked position. Knob  42   b , on top of locking pin  38   b , can be grasped to retract locking pin  38   b . Knob  42   b  defines cutout  44   b  along its lower edge, corresponding to shelf  46   b , attached to the top surface of sliding member  22 . When pin  38   b  is in the locked position, shelf  46   b  fits within cutout  44   b , and the end  48   b  of pin  38   b  protrudes from the bottom of the rotating plate  26 , fitting within one of the holes  52  in sliding member  22 . When pin  38   b  is retracted and rotated, the edge  50   b  of knob  42   b  rests on shelf  46   b , securing pin  38   b  in the unlocked position, wherein end  48   b  of pin  38   b  does not protrude from rotating plate  26 , and rotating plate  26  is free to rotate within a horizontal plane around shaft  28 . 
     Referring to FIGS. 5 and 6, handle  36  is supported between arms  32 , 34  of brace  30 . Handle  36  is an elongated cylinder with a first end having a round protrusion  54  with a smaller diameter than the rest of the cylinder. A central bore  56  corresponds to the longitudinal axis of the cylinder. The central bore is round, but has a square hole  58  within the protrusion  54 . Although a square hole  58  is preferred, many other noncircular shaped holes  58  can be utilized with equal effectiveness. Handle pin  60  is contained within central bore  56 , with a round portion  62  corresponding to the round portion of central bore  56 , and a square knob  64  corresponding to square hole  58 . The handle pin is biased by spring  66  so that the square knob  64  fits within square hole  58 . 
     Arm  34  includes a round hole  68 , and arm  32  includes a round recessed portion  70  for receiving round protrusion  54  of handle  36 . The recessed portion  70  includes a square hole  72  for receiving square knob  64 , and a square indentation  74 , having the same center as square hole  72  but rotated 45° from square hole  72 . Handle pin  60  passes through round hole  68 , central bore  56  including square hole  58 , and square hole  72  in arm  32 . Handle  36  is thereby supported at arm  34  by handle pin  60 , and at arm  32  by round protrusion  54 . When handle pin  60  is in the locked position, square knob  64  fits within the handle&#39;s square hole  58  and the square hole  72  in arm  32 , thereby preventing rotation of handle  36  relative to arms  32 , 34 . When square knob  64  is retracted, rotated 45°, and placed within square indentation  74 , it is biased into indentation  74  by spring  66 , preventing square knob  54  from entering square holes  58 , 72 , and allowing the handle  36  to rotate freely around handle pin  60 . 
     It should be noted that, if a shape other than square is used for the handle pin&#39;s knob  64  and corresponding holes, the indentation  74  need not be rotated 45° from hole  72 , but may be rotated to any degree sufficient to secure knob  64  in the unlocked position. 
     To use the invention, the user  76  first decides the level and type of difficulty he wishes to add to his pushups. If the user  76  wants to force himself to control the lateral sliding motion of the handles, he retracts the locking pins  38  of sliding member  22 , thereby permitting the sliding member  22  to slide laterally within base  12 . Otherwise, he inserts the locking pins  38  of sliding member  22  into holes  24 , locking the sliding members in place. If the user  76  wants to force himself to control rotation of the handgrips  36  in a horizontal plane, he retracts the locking pins  38  of rotating plate  26 , thereby allowing rotating plate  26  to rotate horizontally. Otherwise, he inserts the locking pins  38  of the rotating plate  26  into the holes  52 , thereby locking rotating plate  26  in position with respect to sliding member  22 . If the user  76  chooses to lock rotating plate  26  in place, he may first orient the handle  36  so that it is either parallel to or perpendicular to the base  12 . Lastly, if the user  76  wants to force himself to control the rotation of the handgrips around their axis, he retracts the handle pins  60 , thereby allowing the handles to rotate. Otherwise, he inserts pins  60 , thereby locking the handgrips in place. User  76  then assumes a pushup position, grasping a handle  36  in each hands, and proceeds to perform pushups up to his level of fitness. 
     It is to be understood that the present invention is not limited to the embodiment described above, but encompasses any and all embodiments within the scope of the following claims.