Abstract:
A device that exercises the muscles of a person who lays down on a bench ( 12 ), by the person shifting his body to counteract a tendency of the bench to tilt to one side or the other. The bench is supported on coil springs ( 44 ) that tilt when the person&#39;s weight shifts to one side as the person performs exercises while laying on the bench.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    People often exercise while lying on a bench, as by lifting weights with their hands. Such exercise usually does not exercise the person&#39;s core muscles. An exercise device that enabled a person lying on a bench, to exercise the person&#39;s core muscles would be of value. 
         [0002]    My earlier Pat. No. 7,645,221 describes an exercise device that has a platform supported on coil springs, that encourages a person to exercise by shifting his weight to control platform tilt. However, that device does not provide sufficient exercise for the muscles of the chest. 
       SUMMARY OF THE INVENTION 
       [0003]    In accordance with one embodiment of the invention, applicant provides an exercise device that allows a person who lies down on a bench facing down (prone) or facing up (reclined), and who exercises by lifting weights, to exercise his/her chest and related muscles. The bench is an elongated platform with a horizontal upper surface of a sufficient length (e.g. 4 to 5 feet) to support the person in the horizontal position. The bench is supported on springs such as coil springs and is free to tilt. When the person moves, as to repeatedly lift and lower weights, he tends to shift weight laterally and the bench tends to tilt to one side or the other. The person tries to return the bench upper surface to the horizontal by shifting his weight, and in so doing exercises his chest and other abdominal muscles, for better balance and stabilization. 
         [0004]    The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is an isometric view of a tilting exercise device, with the bench and a person on the bench, shown in phantom lines. 
           [0006]      FIG. 2  is a rear elevation view of the device of  FIG. 1 , showing a person sitting on the bench. 
           [0007]      FIG. 3  is an isometric view of the device of  FIG. 1 , with the person shown in phantom lines in a horizontal position and in a sitting position. 
           [0008]      FIG. 4  is a sectional view of another construction of spring. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0009]      FIG. 1  shows an exercise device  10  of the invention, which includes a bench  12  with an upper surface  70  that is primarily (±10°) horizontal and with laterally opposite sides  16 . 
         [0010]    The bench is designed to receive a person in a reclined position Pr (face up) or a prone position Pp (face down, not shown in  FIG. 1 ). The bench has a length L that is preferably 4 to 5 feet to support three-quarters of body length (hips to head) of the person. The bench is supported by a base  14  that is, in turn, supported on a floor surface  20  (e.g. a wooden, concrete, or even dirt floor). The bench  12  is shown in phantom lines so that the construction of the base  14  can be seen. 
         [0011]    The base  14  includes a rigid frame  22  that includes an elongated beam  24  with downwardly projecting ends  30  and a pair of floor-supported beams  32  at the opposite ends. The frame also includes a pair of cross beams  40 ,  42  that are supported on the elongated beam  24 . The device includes four springs  44  arranged in two pairs  50 ,  52 . 
         [0012]    Each spring  44  has a lower spring end  60  supported on one of the cross beams  40 ,  42  and an upper spring end  62  attached to the bench  12 . Each spring is a coil spring with a . primarily vertical axis  64 . The springs are arranged so they support the bench with its upper surface  70  being free of tilt from the horizontal, when no torque is applied to the bench that would tilt it about a horizontal length axis  72 . However, the springs are also arranged so a small torque can tilt the bench about the axis  72 . 
         [0013]      FIG. 2  shows that the angle B that the bench will tilt is determined by the bench resistance to tilt and the torque applied to the bench. The bench resistance to tilt decreases if the springs of a pair such as  50  are moved closer together, if the springs are taller, or if the springs have a smaller diameter  74 .  FIG. 3  shows a person P moving weights W up and down. Such movement usually results in shifting some weight sidewards, which causes the bench to tilt. 
         [0014]    Applicant prefers to provide stops  80  that limit tilt of the bench to an angle such as 30° from the horizontal. The bench should tilt by a plurality of degrees from the horizontal when a person of a weight of 140 to 200 pounds has shifted laterally L by more than one inch from a center location at which the bench upper surface is horizontal. 
         [0015]    Although a coil spring is a simple spring to use, it is also possible to use a spring  100  ( FIG. 4 ) formed by a piston  102 , a cylinder  104 , and a quantity  106  of elastic material (solid or gas) in the cylinder. 
         [0016]    Applicant has designed an exercise device of the construction shown in  FIGS. 1-3 . The coil springs were each formed of steel wire of one-eighth inch diameter wound into coils of 2 inches outside diameter and 3 inches height. The two coils of each pair were spaced apart by 8 inches and were each spaced from the axis  72  by 3 inches. 
         [0017]    Thus, the invention provides an exercise device that encourages exercising the muscles at the core and front of a person&#39;s torso (chest), especially when the person is performing weight-lifting exercises while lying on a bench. The device includes a bench for supporting the person lying in a horizontal position and with his face up (reclined) or face down (prone), a base that is supported on a floor, and means for supporting the bench on the base. The means for supporting produces noticeable (a plurality of degrees) tilt of the bench axis  72  when a torque of thirty-three foot-pounds has been applied (the center of a person weighing 200 pounds is spaced more than 2 inches from the bench axis). 
         [0018]    Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art, and consequently, it is intended that the claims be interpreted to cover such modifications and equivalents.