Wheel chair abstract
This improvement is for a hand operated wheel chair or exercise
machine. The machine uses two racks to operate two one way clutches
to furnish forward motion from both the forward and backward strokes
of the input lever arm. The mechanical advantage of the input lever
arm is readily changeable to affect the overall gear ratio of the
drive. Steering is accomplished by turning a wheel on the lever
arm. The control is similar to that on a wheel controlled airplane.
Wheel chair claims
What is claimed:
1. A vehicle comprising:
a vehicle frame assembly;
a plurality of wheels attached to said vehicle frame assembly;
a steering wheel assembly attached to the vehicle and including
a steering wheel and including a lever arm with two opposite ends,
one end of said lever arm attached to the steering wheel and the
other end of said lever arm attached to the vehicle and wherein
said steering wheel assembly permits steering at least one of the
plurality of wheels and wherein the vehicle can be propelled by
pushing the steering wheel assembly back and forth;
a transmission assembly including two racks, two gear driven one
way clutches, a jack shaft, a dog clutch controlled chain drive,
and a differential;
the two racks operating the two gear driven one way clutches wherein
the two racks and two gear driven one way clutches are adapted to
respond to a steering assembly back and forth motion and whereby
a reciprocating motion of the steering wheel assembly is transformed
to a rotary motion by the two racks operating the two gear driven
one way clutches and wherein one of said gear driven one way clutches
locks on a pull stroke and the other gear driven one way clutch
locks on a reverse stroke of the steering wheel assembly and wherein
the gear driven one way clutches rotate the jack shaft to transfer
power to at least one wheel of the plurality of wheels through the
dog clutch controlled chain drive and the differential;
said dog clutch controlled chain drive being capable of multiple
gear ratios;
a lever arm output portion slidably attached to said lever arm
at a predetermined position on said lever arm and wherein said lever
arm output portion is held in place on said lever arm by two bar
clamp washer clutches and wherein said predetermined position of
said lever arm output portion can be varied;
said back and forth motion of said steering wheel assembly applying
an amount of torque through said lever arm and through said lever
arm output portion to said transmission assembly and wherein the
amount of torque can be varied by varying the predetermined position
of the lever arm output portion on said lever arm;
two pull cables;
each of said pull cables having two opposite ends, one end of each
pull cable attached to the steering wheel assembly and the other
end of each pull cable attached to the vehicle frame assembly and
whereby rotation of the steering wheel will apply a steering force
to at least one of the plurality of wheels through said pull cables.
2. A vehicle comprising:
a vehicle flame assembly;
a plurality of wheels attached to said vehicle frame assembly;
a steering wheel assembly attached to the vehicle and including
a steering wheel and including a lever arm with two opposite ends,
one end of said lever arm attached to the steering wheel and the
other end of said lever arm attached to the vehicle and wherein
said steering wheel assembly permits steering at least one of the
plurality of wheels and wherein the vehicle can be propelled by
pushing the steering wheel assembly back and forth;
a transmission assembly including two roller chain assemblies wherein
each roller chain assembly includes a roller chain fastened to a
stiffening member, said transmission assembly further including
two sprocket driven one way clutches, a jack shaft, a dog clutch
controlled chain drive, and a differential;
the two roller chain assemblies operating the two sprocket driven
one way clutches wherein the two roller chain assemblies and two
sprocket driven one way clutches are adapted to respond to a steering
assembly back and forth motion and whereby a reciprocating motion
of the steering wheel assembly is transformed to a rotary motion
by the two roller chain assemblies operating the two sprocket driven
one way clutches and wherein one of said sprocket driven one way
clutches locks on a pull stroke and the other sprocket driven one
way clutch locks on a reverse stroke of the steering wheel assembly
and wherein the sprocket driven one way clutches rotate the jack
shaft to transfer power to at least one wheel of the plurality of
wheels through the dog clutch controlled chain drive and the differential;
said dog clutch controlled chain drive being capable of multiple
gear ratios;
a lever arm output portion slidably attached to said lever arm
at a predetermined position on said lever arm and wherein said lever
arm output portion is held in place on said lever arm by two bar
clamp washer clutches and wherein said predetermined position of
said lever arm output portion can be varied;
said back and forth motion of said steering wheel assembly applying
an amount of torque through said lever arm and through said lever
arm output portion to said transmission assembly and wherein the
amount of torque can be varied by varying the predetermined position
of the lever arm output portion on said lever arm;
two pull cables;
each of said pull cables having two opposite ends, one end of each
pull cable attached to the steering wheel assembly and the other
end of each pull cable attached to the vehicle frame assembly and
whereby rotation of the steering wheel will apply a steering force
to at least one of the plurality of wheels through said pull cables.
3. A vehicle comprising:
a vehicle frame assembly;
a plurality of wheels attached to said vehicle frame assembly;
a steering wheel assembly attached to the vehicle and including
a steering wheel and including a lever arm with two opposite ends,
one end of said lever arm attached to the steering wheel and the
other end of said lever arm attached to the vehicle and wherein
said steering wheel assembly permits steering at least one of the
plurality of wheels and wherein the vehicle can be propelled by
pushing the steering wheel assembly back and forth;
a transmission assembly including two racks, two gear driven one
way clutches, a jack shaft, a dog clutch controlled chain drive,
and a differential;
the two racks operating the two gear driven one way clutches wherein
the two roller chain assemblies and two gear driven one way clutches
are adapted to respond to a steering assembly back and forth motion
and whereby a reciprocating motion of the steering wheel assembly
is transformed to a rotary motion by the two racks operating the
two gear driven one way clutches and wherein one of said gear driven
one way clutches locks on a pull stroke and the other gear driven
one way clutch locks on a reverse stroke of the steering wheel assembly
and wherein the gear driven one way clutches rotate the jack shaft
to transfer power to at least one wheel of the plurality of wheels
through the dog clutch controlled chain drive and the differential;
said dog clutch controlled chain drive being capable of multiple
gear ratios;
a lever arm output portion slidably attached to said lever arm
at a predetermined position on said lever arm and wherein said lever
arm output portion is held in place on said lever arm by a screw
shaft and a screw nut and wherein said predetermined position of
said lever arm output portion can be varied;
said back and forth motion of said steering wheel assembly applying
an amount of torque through said lever arm and through said lever
arm output portion to said transmission assembly and wherein the
amount of torque can be varied by varying the predetermined position
of the lever arm output portion on said lever arm;
two pull cables;
each of said pull cables having two opposite ends, one end of each
pull cable attached to the steering wheel assembly and the other
end of each pull cable attached to the vehicle frame assembly and
whereby rotation of the steering wheel will apply a steering force
to at least one of the plurality of wheels through said pull cables.
4. A vehicle comprising:
a vehicle frame assembly;
a plurality of wheels attached to said vehicle frame assembly;
a steering wheel assembly attached to the vehicle and including
a steering wheel and including a lever arm with two opposite ends,
one end of said lever arm attached to the steering wheel and the
other end of said lever arm attached to the vehicle and wherein
said steering wheel assembly permits steering at least one of the
plurality of wheels and wherein the vehicle can be propelled by
pushing the steering wheel assembly back and forth;
a transmission assembly including two racks, two gear driven one
way clutches, a jack shaft, a dog clutch controlled chain drive,
and a differential;
the two racks operating the two gear driven one way clutches wherein
the two roller chain assemblies and two gear driven one way clutches
are adapted to respond to a steering assembly back and forth motion
and whereby a reciprocating motion of the steering wheel assembly
is transformed to a rotary motion by the two racks operating the
two gear driven one way clutches and wherein one of said gear driven
one way clutches locks on a pull stroke and the other gear driven
one way clutch locks on a reverse stroke of the steering wheel assembly
and wherein the gear driven one way clutches rotate the jack shaft
to transfer power to at least one wheel of the plurality of wheels
through the dog clutch controlled chain drive and the differential;
said dog clutch controlled chain drive being capable of multiple
gear ratios;
a lever arm output portion slidably attached to said lever arm
at a predetermined position on said lever arm and wherein said lever
arm output portion is held in place on said lever arm by a gear
rack and pinion gear and wherein said predetermined position of
said lever arm output portion can be varied;
said back and forth motion of said steering wheel assembly applying
an amount of torque through said lever arm and through said lever
arm output portion to said transmission assembly and wherein the
amount of torque can be varied by varying the predetermined position
of the lever arm output portion on said lever arm;
two pull cables;
each of said pull cables having two opposite ends, one end of each
pull cable attached to the steering wheel assembly and the other
end of each pull cable attached to the vehicle frame assembly and
whereby rotation of the steering wheel will apply a steering force
to at least one of the plurality of wheels through said pull cables.
Wheel chair description
BACKGROUND OF INVENTION
Many types of wheel chairs or exercise machines exist but none
of them offer a simple way to make an all terrain wheel chair with
simple arm motion power input. The following U.S. prior patents
have been found in searches, but none of them provide a simple cheap
easy to use chair: U.S. Pat. Nos. 4,811,964; 4,892,323; 5,020,815;
5,020,818; 5,036,937; 5,149,118; 5,167,168; 5,240,277; 5,232,236;
5,236,398; 5,241,876; 5,312,126; 5,312,127; 5,322,312; 5,301,971;
5,308,098.
SUMMARY OF INVENTION
This invention is a two wheel drive all terrain wheel chair or
exercise machine that is powered by pushing and pulling on a wheel.
The wheel also steers the chair by being turned while it is being
pumped.
It has a step-less transmission which changes its input lever advantage
to facilitate torque multiplication. The output lever arm is lengthened
or shortened by sliding the output bearing mount up and down the
lever to which the steering wheel is attached.
Power is transmitted to the wheels on both the push and the pull
strokes of the steering wheel. Power is put onto a jack shaft by
using two racks to turn two one way clutches through attached gears.
One rack turns a one way clutch in its locked direction on the pull
stroke, and the other rack turns a separate one way clutch in its
locked direction on the push stroke. Both clutches combine to turn
the jack shaft in the correct forward direction on each stroke.
The chair is steered and shifted by using small diameter pull cables
in its preferred configuration.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1: Side view of the assembled wheel chair showing the position
and the interaction of its several parts.
FIG. 2: Top view of the assembled wheel chair showing the position
and the interaction of its several parts.
FIG. 3: An enlargement of the output bearing sleeve; this illustrates
& shows how two `bar clamp clutches` are used to restrain and
position the sliding mount.
FIG. 4: Side view enlargement of the input racks intermeshed with
the clutches.
FIG. 5: Top view of the input racks intermeshed with their respective
clutches.
FIG. 6: An alternate style of rack formed by appropriately fastening
a length of roller chain to a stiffening bar.
FIG. 7: An enlargement of the output bearing mount using a worm
gear shaft and a worm nut to restrain and position the sliding mount.
FIG. 8: An enlargement of the output bearing mount using a rack
and pinion to restrain and position the sliding mount.
DETAILED DESCRIPTION
This invention is an improvement in the design of an arm operated
wheel chair or exercise machine wherein a lever arm is used to provide
forward motion.
A seat would be mounted to frame 6; the seat has been omitted.
Referring in detail to FIGS. 1 and 2: Wheel 10 is used to pump
lever arm 7A back and forth. Lever arm 7A moves sleeve 4. Bearing
13 moves interconnector bar 20. Interconnector bar 20 moves racks
3.
Racks 3 are used to rotate one way clutch 17 which rotates sliding
output dog clutch 14. Sliding output dog clutch 14 turns chain 2
which turns sprocket 5. Sprocket 5 is attached to differential 12.
Differential 12 turns wheels 1 to provide forward motion. Extra
sprockets can be included at 5 for changing final gear ratio.
The wheel chair is steered by turning wheel 10 which turns input
cable wheel 16. Input cable wheel 16 shortens and lengthens cables
11 to turn output cable wheel 9. Output cable wheel 9 turns wheel
8 to steer the chair.
FIG. 3 is an enlargement of sliding output bearing sleeve 4. It
shows lever arm 7A and bearing 13. Bearing 13 is attached to sleeve
4. Sleeve 4 is locked in position by "bar clamp clutches"
4A and 4B. ("Bar clamp clutches" are hardened washers
with a center hole larger than the shaft they are placed around.
When cocked and held in that position, they bind and prevent movement
between their retainer and shaft. These clutches are normally used
on pipe-style bar clamps.) Bar clamp clutches 4A stop sleeve 4 from
sliding in direction of arrow 32. Bar clamp clutches 4B stop sleeve
4 from sliding in the direction of arrow 33.
Bar clamp clutches 4A are released by cable 14A. Cable 14A pushes
bar clamp clutches 4A down against sleeve 4 allowing sleeve 4 to
slide down the lever arm 7A toward bearing 7 in FIG. 1. Releasing
bar clamp clutches 4A and pushing lever arm 7A toward wheel 8 in
FIG. 1 slides sleeve 4 down lever arm 7A and increases the torque
output of lever arm 7A at bearing 13. Releasing bar clamp clutches
4B allow sleeve 4 to slide up lever arm 7A when lever arm 7A is
pulled toward differential 12 in FIG. 1.
FIGS. 4 and 5 depict racks 3T and 3B which are used to drive one
way clutches 17 and 18. When rack 3B is moved in the direction of
arrow 30, it rotates its gear 19 in a clockwise direction and drives
clutch 17 in a clockwise direction. Clutch 17 is locked in a clockwise
direction, so shaft 21 is driven in a clockwise direction.
When rack 3T is moved in the direction of arrow 31, it rotates
its gear 19 in a clockwise direction. Gear 19 drives clutch 18 in
a clockwise direction. Clutch 18 is locked in a clockwise direction,
so shaft 21 is driven in a clockwise direction.
Clutches 17 and 18 are one way clutches and can be one of many
types; some choices are ramp and roller, sprague, ratchets, mechanical
diodes and overrunning starter drives off of engine starters. These
clutches are not limited to these types.
FIG. 6 illustrates a second type of rack. This rack is formed by
adequately attaching roller chain to a rigid backing. These racks
drive sprockets which are attached to one way clutches. Roller chain
24 can be welded or bolted at 23 to bar 22.
FIG. 7 is an alternate style of retaining and adjusting sliding
output bearing sleeve 4. Threaded shaft 26 is rotated to move nut
25. Nut 25 slides sleeve 4 on lever arm 7A. The pitch of the thread
locks sleeve 4 in place until the threaded shaft is turned.
FIG. 8 is an alternate style of positioning and adjusting sliding
output, bearing sleeve 4. Rack 28 is fastened to lever arm 7A. Pinion
gear 27 is turned to position sleeve 4 along rack 28. Sleeve 4 is
moved by the pinion gear 27 along lever arm 7A. |