Isometric exercising device

An exercise device for elderly and handicapped persons having J-shaped pedal bars pivotally mounted to a frame. Pedal bars terminate in foot pedals extending perpendicularly outwardly from the pedal bars and move in a substantially linear back-and-forth type motion. A cord fastened at each end to a pedal bar runs through a pulley on the frame to force pedals directions opposite to one another. A shock absorbing bumper prevents damage to the pulley from repeated impacts of the pedal bars. Arms terminating in handles are provided as extensions perpendicularly outwardly from the pedal bars and operate in unison with the pedal bars. A brake is held in pressed contact with the pedal bars by a knob tightened spring to provide adjustable resistance to pedal motion. The device can be used with one or both person's legs and with or without the assistance of the person's hands.

DESCRIPTION 
1. Technical Field 
The present invention relates to portable exercise devices and in 
particular to those foot and arm operated exercise devices for use by 
convalescing, elderly, handicapped or other persons who cannot engage in 
strenuous exercise. 
2. Background Art 
A large variety of exercise equipment is available. Among the most common 
types of exercise device is the exercise bicycle, which resembles an 
ordinary bicycle with the exception that its sole wheel is raised off the 
ground, so it is stationary. These exercise bicycles have become popular 
for both the casual workout and as part of a vigorous exercise program. 
However, exercise bicycles are large and bulky; and somewhat heavy. They 
are difficult to store and are not very portable. Further, these devices 
are not suitable for those who cannot engage in strenuous exercise. 
Dranselka, in U.S. Pat. No. 4,262,902, discloses a portable pedaling type 
exercise device which is attachable to a conventional chair. The force 
required to turn the pedals can be varied by adjusting wingnuts forcibly 
holding brake lining material against the pedal shift. Stirrups may be 
provided on the pedals for securely holding the feet of elderly persons, 
stroke victims, or other handicapped persons to the pedals. U.S. Pat. Nos. 
3,968,963 to Sileo and 4,390,177 to Biran et al. disclose other pedal- and 
chair-type exercise devices. The major advantages of these devices are 
that they are compact and portable, and the users may sit in any chair of 
their choosing for comfort, safety and convenience. 
In U.S. Pat. No. 3,768,808 to Passera, an exercising device is disclosed in 
which a pair of bars is mounted for pivotal movement on a base against 
friction resistance. The user sits in a chair with feet secured to 
stirrups on the top of the bars. Exercise is accomplished by moving the 
bars back and forth or from side to side with the feet. An alternate set 
of bars having springs permits exercise by lifting and lowering. 
In U.S. Pat. No. 4,314,697 to Brumfield et al, an exercise device is 
disclosed which is specifically designed to be used by persons who cannot 
engage in strenuous exercises. An exercise bar mounts to the ends of a 
wedge-shaped base, while a pair of springs provide the necessary 
resistance. The device is designed to be used on the floor so that it is 
easy for elderly and handicapped persons to use. A variety of exercises 
can be performed. 
The problem with these devices is that it may be impossible for people with 
hip injuries or arthritis to use the pedalling type exercise devices, 
because such pedalling motion is injurious or impossible. Further, all of 
these devices require that both limbs be used. Persons paralyzed or 
partially paralyzed in one or both legs due to strokes or crippling 
diseases would be unable to use these exercise devices. 
Accordingly, it is an object of the invention to provide portable exercise 
device that may be used in an ordinary chair or wheelchair by elderly, 
handicapped or other persons. 
It is another object of the invention to provide such an exercise device 
that can be used by persons who don't have full use of both legs, or by 
persons with hip or other joint problems that cannot exercise in a 
pedalling motion. 
DISCLOSURE OF THE INVENTION 
The above objects have been met with an exercise device having pedals which 
move not in a rotary motion, but rather in a substantially linear 
back-and-forth type motion on adjacent J-shaped pedal bars pivotally 
mounted, in an upright manner, to a frame. The device uses an isometric 
principle of exercise in which one group of muscles oppose the efforts of 
others. When one pedal is pushed in one direction, the other pedal is 
forced in the opposite direction. This opposition of pedals is created by 
a pulley and a cord fastened to both pedal bars, running through the 
pulley. Persons with only one strong leg can still exercise their weak or 
paralyzed leg because the action of the strong leg on one pedal moves the 
weak leg on the opposite pedal. 
A pair of arms extend beyond the pivot from the pedal bars and terminate in 
handles. These arms pivot in unison with the pedal bars and may be used to 
assist the exercising of weak or partially paralyzed legs. Pulling back on 
the left handle, for example, pushes in the left pedal and forces out the 
right pedal. 
An adjustable friction plate is held in pressed contact with the pedal bars 
to increase resistance as may be desired by the user. A knob turns to 
increase tension of a spring attached to the friction plate. 
A shock absorbing bumper is provided on the frame to prevent damage by the 
pedal bars repeatedly striking the frame and pulley. 
With this device handicapped and elderly persons previously unable to 
engage in exercise can strengthen their muscles without discomfort. The 
user may sit in a chair or wheelchair of his or her own choice, thus 
eliminating the load and wear on deteriorating or arthritic joints, 
particularly the hip joint. Persons who can use only one leg, such as 
stroke victims, can also exercise their limbs to prevent muscles from 
atrophying.

BEST MODE FOR CARRYING OUT THE INVENTION 
With reference to FIG. 1, an exercise device 10 is adapted for operation by 
a person 12 sitting in a chair 14. Chair 14 is only illustrative and may 
be any chair or wheelchair of the person's choice. Exercise device 10 has 
a boxlike frame 16 mounted on a base 18. Base 18 is generally flat and 
acts to stabilize exercise device 10. 
A pair of J-shaped pedal bars 20 and 22 are pivotally mounted to frame 16 
on a pivot shaft 24. Each pedal bar 20 and 22 terminates in a pedal 26 and 
28, extending perpendicularly outwardly from the pedal bar. Feet 30 and 32 
of a person 12 act on pedals 26 and 28 respectively to push them 
alernatively back and forth in a generally linear motion. Pedals 26 and 28 
are typically made of a material such as rubber to prevent the feet from 
slipping. The pedals may optionally be equipped with stirrups to retain 
the feet in place. 
Exercise device 10 has arms 34 and 36 colinearly extending beyond pivot 
shaft 24 from pedal bar 20 and 22. Each arm 34 and 36 terminates in a 
handle 38 and 40, respectively, extending perpendicularly outwardly from 
the pedal bar, which can be acted on by hands 42 and 44 of person 12. Arms 
34 and 36 act in unison with pedal bars 20 and 22, pivoting about shaft 
24. Thus when handle 38 is pushed, for example, pedal 26 moves in the 
opposite direction. Similarly, handle 40 and pedal 28 move in opposite 
directions. 
With reference to FIGS. 2-4, frame 16 is a boxlike construction of metal, 
plastic, wood or other sturdy material. Typically, frame 16 is about six 
inches wide, nine inches long, and sixteen inches high 
(15.times.23.times.42 cm) but other size frames may also be used. 
Base 18 is generally flat, and is longer and wider than frame 16. 
Typically, base 18 is about one-half inch high, fourteen inches wide, and 
twenty-six inches long (1.times.36.times.66 cm) but other size bases may 
also be used. Base 18 provides stability to exercise device 10 and may be 
made of rubber or other, preferably nonslippery, material. Frame 16 may be 
mounted anywhere on base 18, but is usually mounted near one of the short 
sides with the pedals 26 and 28 projecting toward the opposite side. 
Pedal bars 20 and 22 are mounted to a shaft 24, the shaft being pivotally 
supported at the front upper edge of boxlike frame 16 on a pivot shaft 24. 
Pivot shaft 24 may be a single rod, screwed into frame 16, with a pair of 
cylinders, slipped onto the rod and welded to pedal bars 20 and 22, 
serving as journal bearings. Any other way of pivotally mounting pedal 
bars 20 and 22 to frame 16 may also be used. 
Pedal bars 20 and 22 have a J-shape, including a straight part 46 and an 
arcuate part 48. Straight part 46 starts at pivot shaft 24 and typically 
extends for about fifteen inches (38 cm). Straight part 46 bends into 
arcuate part 48 at a bend 50. Arcuate part 48 is typically about twelve 
inches long (30 cm) with a radius of curvature of the length of straight 
part 46. Arcuate part 48 of pedal bars 20 and 22 projects through openings 
49 in frame 16 and terminates in pedals 26 and 28. Straight part 46 and 
arcuate part 48 of pedal bars 20 and 22 may be a single contiguous piece, 
or alternatively may be two distinct pieces joined together, but in any 
case operate together as one piece. Pedal bars 20 and 22 are preferably 
metal or other strong, durable material. 
A pulley 52 is secured by a block 54 to frame 16. Pulley 52 is located 
between pedal bars 20 and 22 on the front part of frame 16 between shaft 
24 and openings 49. Preferably, pulley 52 is level with the bottom end, 
near bend 50, of straight part 46 for greater range of motion and smoother 
operation. 
A cord 56 is tied at one end to pedal bar 20 by a tie 58, runs through 
pulley 52, and is tied at an opposite end to pedal bar 22 by a tie 60. The 
term "cord" is used here as a general term for any cable, wire, cord, 
rope, string, band, line or chain that may be used in connection with a 
pulley. Metal cable is preferred for its durability, but any cord material 
may be used for cord 56. Cord 56 is typically about ten inches (25 cm) 
long. 
A bumper 62 is mounted to the front part of frame 16 above pulley 52. 
Bumper 62 is typically made of wood or hard rubber and has a shock 
absorbing pad 64. Pad 64 is made of foam or other shock absorbing material 
and is disposed to absorb the shock from the straight part 46 of pedal 
bars 20 and 22. Bumper 62 protects pulley 52 and frame 16 from repeated 
blows from the pedal bars 20 and 22. 
Exercise device 10 has arms 34 and 36 which extend upward from pedal bars 
20 and 22 respectively and terminate in handles 38 and 40. Arms 34 and 36 
may be contiguous with pedal bars 20 and 22 as one piece, or they may be 
fitted over and secured to the ends of pedal bars 20 and 22. Typically, 
arms 34 and 36 are metal or other strong, durable material and are about 
18 inches (45 cm) long. 
A brake 66 is connected to frame 16 beneath arcuate part 48 of pedal bars 
20 and 22 and is held in pressed contact with pedal bars 20 and 22 for 
applying a resistive force to pedal bars 20 and 22. Brake 66 is typically 
a four by six inch flat plate (10.times.15 cm) of a high friction 
material, such as rubber. Wood with grooves for seating pedal bars 20 and 
22 may also be used. 
Brake 66 is held against pedal bars 20 and 22 by a spring 68. Spring 68 is 
typically a conventional spring about eight inches (20 cm) long and 
fastened at one end to brake 66 by a cotter pin 76. Other fasteners can 
also be used instead of cotter pin 76. Spring 68 is fastened on the 
opposite end to a rod 70. Rod 70 is in turn screwed into a knob 72 on top 
of frame 16 for adjusting the tension of spring 68. Rod 70 is generally 
cylindrical in shape and 3 inches (8 cm) long. Its end opposite spring 68 
has an internal screw for receiving an external screw 74, part of knob 72. 
Turning knob 72 in one direction screws external screw 74 into rod 70, 
drawing rod 70 closer to frame 16. This action stretches spring 68, 
increasing its tension and increasing the pressure of brake 66 on pedal 
bars 20 and 22. Turning knob 72 in the opposite direction reduces the 
pressure of brake 66 on pedal bars 20 and 22. 
In operation, pushing on one pedal, pedal 26 for example, draws cord 56 
attached to pedal bar 20 at tie 58 through pulley 52. Cord 56 is also 
attached to pedal bar 22 at tie 60, so as cord 56 is drawn through pulley 
52, pedal 28 is forced in the opposite direction from pedal 26. Similarly, 
pushing pedal 28 forces pedal 20 in the opposite direction. 
Arms 34 and 36 operate in unison with pedal bars 20 and 22. Pulling on one 
arm, arm 34 for example, causes corresponding pedal bar 20 and pedal 26 to 
be pushed toward frame 16. Pedal 28 is forced in the direction of motion 
of arm 34. Similarly, pulling on arm 36 moves pedal 26 in the same 
direction and pedal 28 toward frame 16. 
Arcuate part 48 of pedal bars 20 and 22 have a range of motion of about 
eight inches (20 cm). For pedal bars 20 and 22 having fifteen inch (38 cm) 
long straight parts 46, the pivoting motion of the pedal bars can occur 
over only about a 30 degree arc. This range of motion for pedal bars 20 
and 22 is limited by bumper 62 in the front and by frame 16 and the length 
of cord 56 in the back. Because pivoting occurs over only about 30 degrees 
of arc, motion of pedals 26 and 28 is substantially linear, rather than 
rotary. 
Exercise device 10 can be operated with a person's legs or by all four 
limbs in a coordinated motion. If one leg is weak or paralyzed, then 
pushing on a pedal with the good leg forces the other pedal in the 
opposite direction. The weakened leg then suppresses its pedal either by 
its own weight, or with the help of one or both hands on the handles 38 
and 40. If both legs are weak or paralyzed, the device 10 can be operated 
solely with a person's hands. In the situation involving only foot 
operation, the pedal bars are needed, but the arms are not. A devise 
without arms is indicated by broken lines 80 in FIG. 1. In the situation 
involving hand and leg operation, arms as well as pedal bars are needed. 
In both situations tensions must be maintained on cord 56 to promote 
isometric excercise of the user's limbs.