Abstract:
An abdominal training apparatus designed to be used by a seated exerciser for concentrated training of the abdominal muscles, comprising an upper portion and a lower portion pivotably suspended from a base, the upper portion and lower portion being linked together causing them to rotate in opposite directions from, in a fixed angular proportion to, one another. The apparatus includes weight addition means on the upper and lower portions to respectively increase and decrease the force required to perform the crunch exercise, so as to accommodate both advanced and beginning exercisers as well as those with injured or weak abdominal muscles. The apparatus further includes a pivotably mounted seat portion enabling the apparatus to be used by an exerciser to target both the oblique and the frontal abdominal muscles.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates generally to apparatus for exercising and strengthening the abdominal muscles. More specifically, the present invention relates to an apparatus that enables a wide range of exercisers to perform isolated training of both the frontal and oblique abdominal muscles without straining the lower back.  
         [0002]     There are many exercise devices intended to train specific parts of the body. Training of the abdominal muscles can be particularly challenging because of the desire to concentrate the work to the abdominal muscles and at the same time minimize the stress and risk of injury to the lower back. Traditional sit-ups on a flat surface or on an inclined bench are far from optimal for strengthening the abdominal muscles. Beginning the exercise in a flat position puts stress on the spine and the neck and may be very difficult for a person with weak abdominal muscles. Additionally, the traditional sit-up motion engages the hip flexor muscles more than the abdominal muscles. Crunches are better than sit-ups insofar as isolating the abdominals. However, because the movement in performing a crunch is from a position with the back flat on the floor to a crunch position where just the head and shoulders are raised from the floor, the range of motion to which the abdominals are subjected is limited.  
         [0003]     Various resistance-type exercise devices for exercising abdominal muscles have been developed over the years. For example, U.S. Pat. No. 6,544,154 [Forcillo] discloses a pivotable abdominal bench that provides lessened or increased resistance while exercising. Although this apparatus provides the capability to both aid an exerciser with weak abdominal muscles in doing a sit-up and increase the resistance for a more advanced exerciser, it suffers from the basic configuration deficiency of starting the exercise in a flat prone position. Therefore, this device does not minimize lower back stress nor does it concentrate the work to the abdominal muscles as opposed to the hip flexors.  
         [0004]     Another type of device is known as a seated abdominal exercise machine. Generally, this type of machine places an exerciser in a seated position raised off the ground in a framework and includes an upper torso engaging structure that allows the exerciser to bend forwardly into a simulated crunch position against a variable resistance. The present invention is such a device.  
         [0005]     Although various attempts have been made to perfect these machines, there remain several disadvantages to many of the designs. Some of these machines emphasize motions that work the hip flexors more than the abdominal region. Other machines concentrate on moving about a particular axis or axes without fully supporting the head, shoulders, and lower back. Still other versions are limited by other factors such as a limited range of movement.  
         [0006]     U.S. Pat. No. 6,186,926 [Ellis] discloses a seated exercise machine permitting the exerciser to do crunches against weight resistance from a seated position. However, this device does not provide positive assistance to exercisers with weaker abdominal muscles and does not support the exerciser&#39;s back throughout the exercise. Additionally, this device has the exerciser seated in a position where the feet are placed on the floor, which may result in an awkward exercise position for exercisers of various heights.  
         [0007]     U.S. Pat. No. 6,015,372 [Steffee, et al.] discloses a seated exercise machine wherein the exerciser works against a weight stack. However, the exerciser&#39;s back and head are not supported throughout the range of the exercise motion and there is no assistance provided for exercisers with weaker abdominal muscles.  
         [0008]     U.S. Pat. No. 6,752,748 [Scotti] discloses a seated exercise machine whereby the exerciser pulls down on handles from above which cause his feet, which are resting on a platform, to be simultaneously raised from below in a crunching motion. However, this device provides no back or head support for the exerciser, provides neither weight resistance nor assistance to an exerciser with weak abdominal muscles, and has no means for the exerciser to use his legs to assist in actuating the crunching motion.  
         [0009]     Accordingly, it is an object of the present invention to provide an abdominal exercise apparatus for doing crunches that provides continuous support for the head, shoulders, and lower back of the exerciser. It is another object of the present invention to provide a seated abdominal exercise apparatus that does not impose undue stress on the exerciser&#39;s spine. It is a further object of the present invention to provide an abdominal exercise apparatus that concentrates the work on the abdominal muscles of the exerciser.  
         [0010]     It is yet another object of the present invention to provide a seated abdominal exercise apparatus that provides assistance to exercisers with weaker abdominal muscles as well as weight resistance to exercisers with strong abdominal muscles. It is yet a further object of the present invention to provide an abdominal exercise machine that enables an exerciser to strengthen both the frontal and the oblique abdominal muscles by a simple adjustment of the apparatus.  
         [0011]     Other objects will appear hereinafter.  
       SUMMARY OF THE INVENTION  
       [0012]     The present invention provides an abdominal exercise apparatus to be used by an exerciser in a seated position. The apparatus of the present invention is symmetrical left to right and comprises a base from which an upper and a lower portion are pivotably suspended. The upper and lower portions are linked together, causing them to rotate in opposed directions with respect to the base. As an exerciser pulls down on handles extending from the top of the upper portion, drawing the upper portion pivotably forward and downward, the exerciser also pulls up on leg retaining means extending from the bottom of the lower portion, drawing the lower portion pivotably forward and upward, resulting in a sit-up or crunch motion. The upper portion and lower portion rotate in a fixed proportion to, and in opposite directions from, one another. Additionally, because the head is supported and the legs and feet are secured, the apparatus concentrates the intensity of the crunch workout on the abdominal muscles.  
         [0013]     The apparatus of the present invention protects against strain to the spine and lower back by providing support for the head, shoulders, and lower back of the exerciser, the upper portion of the apparatus comprising head and shoulder pads and the lower portion of the apparatus comprising lumbar and seat pads. As the exerciser draws the apparatus into the crunch position, his back and head continue to be supported throughout the entire range of motion.  
         [0014]     The abdominal exercise apparatus of the present invention additionally includes means to add weights to the upper and lower portions in order to both increase and decrease the force required to perform the crunch exercise. An advanced exerciser can benefit by increasing the weight on the upper portion, thereby making the exercise more difficult and enhancing the workout of the abdominal muscles. A beginning exerciser, or one who is rehabilitating from injury or has weak abdominal muscles, can benefit by increasing the weight on the lower portion, thereby making the exercise easier and enabling an exerciser to train using the crunch motion even if he is not capable of achieving that motion unassisted. Further, the apparatus of the present invention enables an exerciser to target both the frontal and the oblique abdominal muscles.  
         [0015]     In addition, the seat portion of the apparatus has the capability of pivoting to the left and right. The seat portion can also be secured in one of a straight ahead position, a leftwardly angled position, or a rightwardly angled position, without the exerciser rising from the apparatus. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]     For the purpose of illustrating the invention, there is shown in the drawings forms which are presently preferred; it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.  
         [0017]      FIG. 1  is a side view of the abdominal training apparatus of the present invention shown in its rest state.  
         [0018]      FIG. 2  is a side view of the abdominal training apparatus of the present invention shown in a partially articulated state.  
         [0019]      FIG. 3  is a side view of the abdominal training apparatus of the present invention shown in its fully articulated state.  
         [0020]      FIG. 4  is a bottom view of the seat of the abdominal training apparatus of the present invention shown in its straight-ahead position, taken along Line  4 - 4  of  FIG. 3 .  
         [0021]      FIG. 4A  is a bottom view of the seat of the abdominal training apparatus of the present invention shown swiveled to its rightwardly angled position (from the perspective of a person seated on the machine) as depicted in  FIG. 4  as taken along Line  4 - 4  of  FIG. 3 .  
         [0022]      FIG. 4B  is a bottom view of the seat of the abdominal training apparatus of the present invention shown swiveled to its leftwardly angled position (from the perspective of a person seated on the machine) as depicted in  FIG. 4  as taken along Line  4 - 4  of  FIG. 3 .  
         [0023]      FIG. 5  is a rear view of the abdominal training apparatus of the present invention shown in its rest state. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0024]     The following detailed description is of the best presently contemplated mode of carrying out the invention. The description is not intended in a limiting sense, and is made solely for the purpose of illustrating the general principles of the invention. The various features and advantages of the present invention may be more readily understood with reference to the following detailed description taken in conjunction with the accompanying drawings.  
         [0025]     Referring now to the drawings in detail, where like numerals refer to like parts or elements, there is shown in  FIG. 1  the abdominal training and exercise apparatus  10  in its rest state, comprising a base  12 , a lower portion  14 , an upper portion  16 , and a seat portion  18 . The base  12  pivotably supports both the upper portion  16  and the lower portion  14  via the upper journal  34  and the lower journal  30 , respectively. A linking bar  74  coordinates the rotational motion of the upper portion  16  and the lower portion  14  with respect to each other. The relative motion of the upper portion  16  and the lower portion  14 , controlled by a four-bar linkage, is the key feature of the apparatus  10 , providing unique exercise benefits and greatly enhancing the range of exercisers who may use the apparatus  10 .  
         [0026]     The apparatus  10  is symmetrical from left to right, as illustrated in  FIG. 5 . The base  12  is fabricated from identical left and right side assemblies  21  interconnected by the bottom cross rail  26  as well as through the upper portion  16  and the lower portion  14  by way of their respective journals  34 ,  30 . The bottom cross rail  26  is fastened to each bottom rail  20  by bolts  27 . Each triangularly shaped side assembly  21  comprises a bottom rail  22 , a front rail  24  affixed to the front portion of the bottom rail  22  and extending upwardly therefrom, and a rear rail  26  affixed to the rear portion of the bottom rail  22  and extending upwardly therefrom, the rear rail  26  being curved frontwardly to join with the front rail  24  near the top thereof. Each side assembly  21  further includes two feet  28 , one extending frontwardly and downwardly from the front end of the bottom rail  22 , the other extending rearwardly and downwardly from the rear end of the bottom rail  22 . Each side assembly  21  is a rigid welded unit that, as part of the base  12 , is capable of supporting the weight of the apparatus  10 , an exerciser seated thereon, and any weight plates  58 ,  90  that may be added to the apparatus  10  during its use. Stop supports  64  and stop pads  62  mounted on the upper, near-horizontal portion of each rear rail  24  shoulder most of the weight of the upper portion  16  when the apparatus  10  is not in use.  
         [0027]     The upper portion  16  supports the back of an exerciser, provides a means for the exerciser to grip the apparatus with his hands for the purpose of articulating the apparatus  10  while exercising, and provides a means for adding weight to increase the difficulty of the exercise. The upper portion  16  comprises a centered vertical back rail  40 , left and right back cross rails  48  extending respectively leftwardly and rightwardly from the mid portion thereof, an upper weight support rail  52  extending downwardly and rearwardly from the mid portion thereof, and a handle support  42  extending leftwardly and rightwardly from the upper rear portion thereof.  
         [0028]     Left and right upper side rails  50  are attached rigidly to the outward facing ends of the back cross rails  48 , extending frontwardly therefrom. Each upper side rail  50  includes a stop pin  60  protruding outwardly from the mid portion thereof, an upper pivot pin  70  protruding outwardly from the front portion thereof, and an upper link pin  72  protruding outwardly from near the front end thereof. The upper lever distance A between the upper pivot pin  70  and the upper link pin  72  is a critical measure for the proper operation of the apparatus  10 .  
         [0029]     The upper portion  16  is suspended from the base  12  by the upper pivot pins  70 , which are pivotably supported in the upper journals  34 . The upper journals  34  are secured to the front rail  22  of the base  12  by the upper journal bolts  36 . When the apparatus  10  is not in use, or between workout sets, the upper portion  16  pivots, under the force of gravity, until the stop pins  60  come to rest on top of the stop pads  62 .  
         [0030]     A weight support base plate  54  extends rearwardly from the bottom end of the back rail  40 , joining with the upper weight support rail  52  to form a rigid triangular structure for supporting any number of upper weight plates  58  which an exerciser may choose to add to increase the workout load of the apparatus  10 . An upper weight peg  56  extends upwardly and rearwardly from the lower portion of the upper weight support rail  52  and is sized to accept standard weight plates  58  such as those used in a gym or fitness center. Weights added to the upper weight peg  56  increase the resistance of the apparatus  10  during the workout. More weights  58  will raise the level of force required to articulate the apparatus  10  into a fully crunched position.  
         [0031]     A head pad  66  is attached to the upper portion, and a back pad  68  to the lower portion, of the front side of the back rail  40 . A pair of handles  44  extends upwardly, frontwardly, and outwardly from the handle support  42  affixed to the upper rear of the back rail  40 , and include handgrips  46  on the ends thereof for an exerciser to grasp while exercising on the apparatus  10 . By pulling the handles  44  downward, the exerciser forces the upper portion  16  to rotate about the upper pivot pins  70 , thereby raising the upper weight plates  58  as the exerciser bends forward into a sit-up or crunch position. The rotating action of the upper portion  16 , combined with that of the cooperating lower portion  14  and an independently positionable swiveling seat portion  18 , provides the exerciser with a focused and safe abdominal workout. The back rail  40 , combined with the head pad  66  and the back pad  68 , provides support throughout the entire range of motion of the exercise and minimizes the stress on an exerciser&#39;s back in completing crunches.  
         [0032]     The lower portion  14  supports the seat and lower back of an exerciser and provides a means for adding weight to decrease the difficulty of the exercise. The lower portion comprises a centered vertical lumbar rail  78 , left and right lumbar cross rails  82  extending respectively leftwardly and rightwardly from the mid portion thereof, a lower weight support rail  86  extending downwardly and rearwardly from the mid portion thereof, and a seat rail  92  extending frontwardly from the bottom end thereof. A lumbar pad  84  is attached to the front side of the lumbar rail  78 .  
         [0033]     Left and right lower side rails  94  are attached rigidly to the outward facing ends of the lumbar cross rails  82 , extending frontwardly therefrom. Each lower side rail  94  includes a lower pivot pin  96  protruding outwardly from near the front end thereof and a lower link pin  76  protruding outwardly from near the rear end thereof. The lower lever distance B between the lower pivot pin  96  and the lower link pin  76  is another critical measure for the proper operation of the apparatus  10 .  
         [0034]     The lower portion  14  is suspended from the base  12  by the lower pivot pins  96 , which are pivotably supported in the lower journals  30 . The lower journals  30  are secured to the front rail  22  of the base  12  by the lower journal bolts  32 . A stop pad  80 , backed by a stop pad support  81 , is fastened to the top end of the lumbar rail  78 . When the apparatus  10  is not in use, or between workout sets, the lower portion  14  pivots, under the force of gravity, until the stop pad  80  comes to rest against the bottom side of the weight support base plate  54  of the upper portion  16 , directly beneath the bottom end of the back rail  40 .  
         [0035]     The lower weight support rail  86  is strong enough to support any number of lower weight plates  90  which an exerciser may chose to add to decrease the workout load of the apparatus  10 . A lower weight peg  88  extends upwardly and rearwardly from the lower portion of the lower weight support rail  86  and is sized to accept standard weight plates  90  such as those used in a gym or fitness center. Weights added to the lower weight peg  88  decrease the resistance of the apparatus  10  during the workout, a feature that may be particularly helpful to beginners or exercisers with weak abdominal muscles. More weights  90  will reduce the level of force required to articulate the apparatus  10  into a fully crunched position, acting to assist a beginning exerciser. Additionally, the interplay between the upper weights  58  and the lower weights  90  may allow an advanced exerciser to fine-tune the loading of the apparatus  10  during a workout. The lower weights  90  counteract proportionally greater upper weights  58 , in a ratio of B/A, i.e., the ratio of the distance of the lower lever, measured between the lower pivot pin  96  and the lower link pin  76 , to that of the upper lever, measured between the upper pivot pin  70  and the upper link pin  72 .  
         [0036]     The rigid link bars  74 , one each on the right and left side of the apparatus  10 , interconnect the upper link pins  72  with the lower link pins  76  and coordinate the rotational motion of the upper portion  16  with the lower portion  14 . Each linking bar  74  completes the four bar linkage that creates the unique benefits of the apparatus  10 . The length of the link bar  74  is fixed so that the back rail  40  and the lumbar rail  78  are aligned when the apparatus  10  is at rest. When the handles  44  are pulled by a seated exerciser to rotate the upper portion  16  downward and inward about the upper pivot pins  70 , the upper link pins  72  push downward on the link bars  74  which in turn push downward on the lower link pins  76 , causing the lower portion  14  to rotate upward and inward about the lower pivot pins  96 .  
         [0037]     The relative amount of rotational motion of the upper portion  16  and the lower portion  14  is fixed by the ratio of the lower lever distance B to the upper lever distance A. For example, if the ratio of B/A equals three, then a 30 degree rotation of the upper portion  16  will cause (approximately) a corresponding 10 degree rotation of the lower portion  14 , so that the total amount of crunch experienced by an exerciser using the apparatus  10  will be about 40 degrees. The opposed directions of rotation of the upper portion  16  and the lower portion  14  explains the reverse effect of the lower weights  90  as opposed to the upper weights  58 . When an exerciser pulls on the handles  44 , he is working against the upper weights  58 , raising them as his torso rotates forward. However, simultaneously, the lower weights  90  are pulling downward on the linking bar  74 , working in the same rotational direction as the exerciser&#39;s hands and helping to rotate his legs upward and inward. Because of the relative distances of the lower lever B and upper lever A, the net effect of a the lower weight plates  90  is reduced proportionally when compared with that of the upper weight plates  58 .  
         [0038]     The seat portion  18  is pivotably supported above the seat rail  92  via the seat journal  108  mounted towards the front portion of the seat rail  92 . The seat portion  18  comprises a swivel rail  100 , a leg extension rail  102  extending downwardly from the front end thereof, and a seat pad  98  affixed on top thereof. A seat pivot pin  110  extends downwardly from the mid portion of the swivel rail  100  and is received by the seat journal  108  in the seat rail  92 , enabling the seat portion  18  to rotate leftwardly and rightwardly. The seat portion  18  can be secured by a seat swivel positioner  112  and cooperating seat swivel pin  114  in one of three angular positions with respect to the seat rail  92 , including straight-ahead (parallel to the seat rail  92 ) and approximately 15 degrees to either the right or left of center. Thereby, an exerciser may exercise the frontal abdominal muscles with the seat portion  18  in the straight-ahead position as well as the oblique abdominal muscles with the seat in either or both of the left and right positions.  
         [0039]     The seat swivel positioner  112  is attached to the front end of the seat rail  92  and has three seat positioning holes  118  corresponding to the three possible positions of the seat portion  18 , to secure the seat portion  18  in each of those positions. A spring loaded seat swivel pin  114  with an associated seat-positioning lever  116  is attached to the underside of the swivel rail  100 . Each of the seat positioning holes  118  is adapted for receiving the seat swivel pin  114  when the seat-positioning lever  116  is released. To rotate the seat portion  18  from one position to another, the seat positioning lever  116  is actuated to pull the seat swivel pin  114  out from one of the seat positioning holes  118 , the seat portion  18  is rotated to the desired position, and the seat positioning lever  116  is released to allow the seat swivel pin  114  to be received into another of the seat positioning holes  118 .  
         [0040]     A leg extension rail  102  extends downwardly and frontwardly from the front of the swivel rail  100 . The leg extension rail  102  supports an ankle bar  104  at the bottom end thereof, the ankle bar  104  extending symmetrically leftwardly and rightwardly therefrom, each side of the ankle bar  104  being covered with an ankle pad  106 . When exercising in the apparatus  10 , a seated exerciser hooks his ankles behind the ankle pads  106  so that his legs may be used to assist in the crunching motion of the apparatus  10 .  
         [0041]     Exercising the front abdominal muscles using the apparatus  10  is a simple procedure. First, the exerciser places the desired weight plates  58 ,  90  on their respective weight pegs  56 ,  88 . For a more difficult exercise, the exerciser will increase the amount of the upper weight plates  58 ; for assistance in the exercise, the exerciser will increase the amount of the lower weight plates  90 . Second, the exerciser sits on the seat pad  98  with his lower back resting against the lumbar pad  84 , his shoulders resting against the back pad  68 , and his head resting against the head pad  66 . The seat portion  18  is in the straight-ahead position. Once seated, the exerciser hooks his ankles behind the ankle pads  106  and reaches up to grasp the handgrips  46  on the handles  44 . Third, the exerciser simultaneously pulls downward with his hands and upward with his knees, actuating the upper portion  16  rotationally downward and inward and the lower portion  14  rotationally upward and inward, resulting in a crunch. Fourth, the exerciser resists the motion of the apparatus  10  as it returns to its rest state, the upper portion  16  rotating upward and outward and the lower portion  14  rotating downward and outward.  
         [0042]     To exercise the oblique abdominal muscles, the seated exerciser need only pivotably reposition the seat portion  18  to the left or to the right by actuating the seat positioning lever  116 , rotating the seat portion  18  to the desired position, and releasing the seat positing lever  116  to secure the seat portion  18  in the desired position. Crunches may then be accomplished in exactly the same manner as for the front abdominal muscle exercises.  
         [0043]     The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, the described embodiments are to be considered in all respects as being illustrative and not restrictive, with the scope of the invention being indicated by the appended claims, rather than the foregoing detailed description, as indicating the scope of the invention as well as all modifications which may fall within a range of equivalency which are also intended to be embraced therein.