Wheel chair abstract
A detachable transmission mechanism for a wheel chair includes
a control unit, two support frames, a suspension frame and a driving
device. The channel clamps of the two support frames can be connected
to two lower transverse rods of an existing wheel chair and the
joining tubes at two sides of the battery unit is connected to the
joining pipe so that the battery unit can be fixed beneath a seat
of the wheel chair; furthermore, the control unit is positioned
on one side of one of armrest of the wheel chair so that in case
of the handle being rotated, the vertical shaft, rotary plate and
the connecting rod can move relatively and in turn rotate the suspension
frame as well as the driving device; and when a control switch is
turned on, the driving wheel can be rotated in either forward or
reversed direction and thus move the wheel chair forward or backward.
Wheel chair claims
What is claimed is:
1. A detachable transmission mechanism for a wheel chair, comprising:
a control unit, having a vertical shaft at an upper end thereof
being attached with a handle, the vertical shaft at a lower end
thereof passing through a hub and being connected to a rotary plate
so that the vertical shaft can move synchronously with the rotary
plate; two support frames, being set up facing each other, each
of the support frames having a L shaped joining pipe with an opening
side thereof being connected to a channel clamp respectively, one
of the joining pipes being connected to a holding bar extending
from a side of the hub; a battery unit, having at least one battery
being placed on top of a box stand with two lower sides thereof
having a joining tube being connected to the joining pipes and thus
fixing the battery unit in position. a suspension frame, being a
U shaped frame with an upper part thereof being connected to the
battery unit through a hollow shaft and a lower part thereof being
connected to the rotary plate via a connecting rod; a driving device,
having an electric motor and an output unit being installed inside
the suspension frame and an output shaft of the output unit being
connected to the driving wheel. whereby, the channel clamps of the
two support frames can be connected to two lower transverse rods
of an existing wheel chair and the joining tubes at two sides of
the battery unit is connected to the joining pipe so that the battery
unit can be fixed beneath a seat of the wheel chair; furthermore,
the control unit is positioned on one side of one of armrest of
the wheel chair so that in case of the handle being rotated, the
vertical shaft, rotary plate and the connecting rod can move relatively
and in turn rotate the suspension frame as well as the driving device;
and when a control switch is turned on, the driving wheel can be
rotated in either forward or reversed direction and thus move the
wheel chair forward or backward.
2. The detachable transmission mechanism for a wheel chair as defined
in claim 1, wherein an adjustable fastening knob is installed between
the vertical shaft and the handle so that the inclination angle
of the handle can be changed.
3. The detachable transmission mechanism for a wheel chair as defined
in claim 1, wherein an adjustable fastening knob is installed between
the vertical shaft and the hub so that an inclination angle of the
hub can be changed.
4. The detachable transmission mechanism for a wheel chair as defined
in claim 1, wherein the U shaped opening of the channel clamp is
attached firmly to the transverse rod with at least one lock bolt.
5. The detachable transmission mechanism for a wheel chair as defined
in claim 1, wherein the box stand of the battery unit at a bottom
thereof is fixedly attached to a stationary tube and a movable tube
fits with the stationary tube to comply with a spacing between the
two transverse rods with the stationary and the movable tubes at
outer sides thereof being attached to a connecting tube respectively
so as to connect with both of the joining pipes firmly.
6. The detachable transmission mechanism for a wheel chair as defined
in claim 1, wherein a shock absorption spring is disposed between
a top of the suspension frame and the driving device.
7. The detachable transmission mechanism for a wheel chair as defined
in claim 1, wherein the driving device further comprises a manual
controller with a follower disk and a lock disk being installed
at an outer wall of a driving wheel sequentially and an engaging
groove being provided on a perimeter of the output shaft, which
passes through an axial hole of the driving wheel and fits with
a key of the lock disk for corresponding to the follower disk and
the lock disk is inserted into a through hole and a catch hole on
perimeter of the shaft hole so that the lock disk can move with
respect to the driving wheel; the lock disk fits with the relay
pipe and a spring and washer are placed in sequence with a fastening
bolt being arranged to pass through and lock onto the output shaft;
whereby, Making use of the lock disk being moved along the relay
pipe and pulled outwards, the spring is compressed and the engaging
projection is free from both the catch hole and the through hole
before a rotation can be conducted with the lock disk in lap contact
with the follower disk at an surface thereof so that the driving
wheel loses a traction thereof and becomes idle.
8. The detachable transmission mechanism for a wheel chair as defined
in claim 7, wherein the axial hole of the driving wheel at both
ends thereof is attached with a bearing respectively.
9. A driving device in a wheel chair, comprising: an electric motor
and an output unit, having an output shaft extending laterally;
and a driving wheel, being connected to the output wheel; characterized
in that: the driving device further comprises a manual controller
with a follower disk and a lock disk being installed at an outer
wall of a driving wheel sequentially and an engaging groove being
provided on a perimeter of the output shaft, which passes through
an axial hole of the driving wheel and fits with a key of the lock
disk for corresponding to the follower disk and the lock disk is
inserted into a through hole and a catch hole on perimeter of the
shaft hole so that the lock disk can move with respect to the driving
wheel; the lock disk fits with the relay pipe and a spring and washer
are placed in sequence with a fastening bolt being arranged to pass
through and lock onto the output shaft; whereby, Making use of the
lock disk being moved along the relay pipe and pulled outwards,
the spring is compressed and the engaging projection is free from
both the catch hole and the through hole before a rotation can be
conducted with the lock disk in lap contact with the follower disk
at an surface thereof so that the driving wheel loses a traction
thereof and becomes idle.
10. The driving device in a wheel chair as defined in claim 9,
wherein the axial hole of the driving wheel at both ends thereof
is attached with a bearing respectively.
Wheel chair description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a detachable transmission
mechanism for a wheel chair and a driving device in the transmission
mechanism and particularly to an electric transmission mechanism
for a wheel chair, with which an existing wheel chair can be attached
by way of DIY (Doing It Yourself). Further, a revised driving device
of the wheel chair is provided in the present invention in which
a driving wheel can be rotationally moved with electric power or
in a state of idling by way of a manual controller being operated
to join with the driving wheel selectively.
[0003] 2. Description of Related Art
[0004] The wheel chair was specially developed for handicapped
or slowly moved aged persons and while a user sits in the wheel
chair and pushes both lateral large wheels with both hands actuating
grip rings coaxially connecting with the large wheels, the movement
of the wheel chair can be obtained purposely. A weak person or a
hand-hindered person resulting from illness or wound usually is
unable to exert a force to the large wheels so that it is necessary
to ask some other persons for gripping the handles at rear side
of the wheel chair before the wheel chair can be moved. Hence, the
conventional wheel chair has to be assisted by the user himself
or any other person in order to meet the basic requirement of movement.
[0005] Accordingly, the so called electric wheel chair has been
developed and the feature of the electric wheel chair is a transmission
mechanism is provided under a "h" shaped seat, that is,
one of two rear wheels is designed as the driving wheel and the
other one rear wheel is the follower wheel so as to constitute a
basis of moving forward. Two front wheels are controlled by a stir
stem located at the armrests being shifted to front, rear, left
or right so that the wheel chair can move toward a direction desired
by the user. Although the conventional wheel chair has a good and
easily operated control device, there still are following deficiencies:
1) the transmission mechanism of the electric wheel chair has to
be driven with the electric power and it becomes unmoved in case
of the electric power is depleted and the basic function of manual
drive has lost; 2) In order to obtain the effect of speed differential
(that is, the inner side rear wheel has a less rotational speed
than the outer side rear wheel) for the two rear wheels and to avoid
turning over or a risk of being unable to turn during the wheel
chair making a turn, a sophisticate speed change box has to be mounted
between the two rear wheels so that it increases the complicity
of the transmission mechanism of the wheel chair; and 3) due to
both the body and the transmission mechanism of the conventional
electric wheel chair being made with complication, the production
cost thereof is pretty high so that the retail price thereof is
much more expensive and is not possible to become prevalent among
handicapped and motion hindered persons.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is provide a detachable
transmission mechanism for a wheel chair, which includes a control
unit, two support frames, a suspension frame and a driving device.
The channel clamps of the two support frames can be connected to
two lower transverse rods of an existing wheel chair and the joining
tubes at two sides of the battery unit is connected to the joining
pipe so that the battery unit can be fixed beneath a seat of the
wheel chair; furthermore, the control unit is positioned on one
side of one of armrest of the wheel chair so that in case of the
handle being rotated, the vertical shaft, rotary plate and the connecting
rod can move relatively and in turn rotate the suspension frame
as well as the driving device; and when a control switch is turned
on, the driving wheel can be rotated in either forward or reversed
direction and thus move the wheel chair forward or backward.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present invention can be more fully understood by reference
to the following description and accompanying drawings, in which:
[0008] FIG. 1 is an exploded perspective view of a detachable transmission
mechanism and a wheel chair attached with the transmission mechanism
according to the present invention;
[0009] FIG. 2 is an assembled perspective view of the transmission
mechanism and the wheel chair shown in FIG. 1;
[0010] FIG. 3 is an exploded perspective view of a driving device
in the transmission mechanism shown in FIG. 1; and
[0011] FIG. 4 is an assembled perspective view of the driving device
shown in FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0012] Referring to FIGS. 1 through 4, the transmission mechanism
of the present invention basically includes a control unit 1, two
support frames 2, a battery unit 3, a suspension frame 4, and a
driving device 5.
[0013] Wherein, the control unit 1 is mainly to provide the driving
device 5 with the function to move forward and change direction.
A handle 12 is attached to the top of the vertical shaft 11 of the
control unit 2 so as to allow the user to hold and control it and
the lower end of the vertical shaft 11 through a hub 13 is connected
to a rotary plate 14 so that the rotary plate can move with the
vertical shaft 11 synchronously. To ensure that the driving device
5 is fully controlled by the control unit 2, a connecting rod 15
is linked between the rotary plate 14 and the suspension frame 4
so that the driving device 5 mounted in the suspension frame 4 can
move forward or turn left and right by way of traction of the connecting
rod 15. In addition, a holding bar 131 is extended from the inner
side of the hub 13 to join the support frame 2 and thus allows the
control unit 1 to be fixedly attached to a lateral side of the armrest
on the wheel chair.
[0014] Further, a fastener 16 is installed at a joint between the
vertical shaft 11 and the handle 12 and at another between the vertical
shaft 11 and the hub 13 respectively. By tightening or loosening
an engaging knob 161 of the respective fastener 16, the handle 12
can be rotated and adjusted to a suitable inclination and fixed
in position. The vertical shaft 11 can be adjusted to a suitable
inclination angle for comply with build types of different users
so that any user can operate the wheel chair with the utmost comfort
due to a factor of human engineering being involved.
[0015] The two support frames 2 are set up facing each other with
the open end of the L shaped joining pipe 21 thereof being connected
to a channel clamp 22 so that the two support frames 2 can fit with
the two respective transverse rods at a base of the wheel chair
so that at least one clip 23 can bind up the opening of the channel
clamp 22 tightly to enclose and retain the transverse rods in position
firmly. One of the support frames 2 has the joining pipe 21 thereof
fitting and engaging with and the holding bar 131 so that the control
unit 1 can be fixedly attached to a lateral side of the armrest.
[0016] The battery unit 3 is the power source of the wheel chair
and consists of a box stand 31 where at least one battery 32 is
installed on the top thereof while a stationary tube 33 is fixed
at the bottom thereof to fit with a movable tube 34 transversely
so as to comply with the spacing between the two transverse rods.
Furthermore, joining tubes 331, 341 are vertically attached to the
stationary and movable tubes 33, 34 respectively so as to engage
with the vertically disposed joining pipes 21. Thus, the battery
unit 3 can then be supported between the two transverse rods.
[0017] The suspension frame 4 is a U shaped frame 41 with an opening
thereof fixedly attaching with the driving device 5. The suspension
frame 4 at the top thereof is connected to the stationary tube 331
through a hollow shaft 42 so that it is possible for the frame 41
to move rotationally. The suspension frame 4 at the bottom thereof
is connected to one end of the connecting rod 15 so as to be pulled
by the connecting rod 15. A shock absorption spring 43 is placed
between the top of the suspension frame 4 and an output part 52
of the driving device 5 in order to provide the effect of sudden
shock.
[0018] The driving device 5 is composed of an electric motor 51,
an output unit 52 and a driving wheel 53. Wherein, the output unit
52, during the implementation, can be assembled with components
such as a turbine reducer, pulleys or gears. When the motor 52 is
turned on, it will allow an output shaft 521, which is laterally
extended from the output unit 52, to rotate in the forward or reversed
direction according to the user's control and the output shaft 521
can in turn move the driving wheel 53 forward or backward. The characteristic
of the present invention is that the driving wheel 53 is connected
to a manual controller 54, that is, the axial hole 531 of the driving
wheel 54 at both ends thereof is attached with a bearing 532 respectively
at least two catch holes 533 are provided at an outer flange surrounding
the axial hole 531. An engaging groove 522 is disposed on the output
shaft 521 longitudinally to pass over the two bearings 532 and a
follower disk 541. A follower disk 541 is provided with a key 542
and a through hole 543 respectively corresponding to the engaging
groove 522 and the catch hole 533 so that the follower disk 541
can rotate synchronously with the driving wheel 53. A lock disk
544 is attached to the outer wall of the follower disk 541 for being
pierced through with a relay pipe 546 and an engaging projection
545 sticks out to correspond to the catch hole 533 such that the
engaging projection 545 can pass though the through hole 533 and
be inserted into the catch hole 533 to make the lock disk 544 rotate
with the driving wheel 53. Besides, the lock disk 544 at the other
side thereof has a spring 547 and a washer 548 being placed one
after another so as to be passed through with an axial bolt 549
for being fastened to the output shaft 521. Hence, once the battery
32 of the battery unit 3 is depleted, the driving wheel 53 is incapable
of turning. At this moment, the only thing has to done by the user
is to hold and pull the lock disk 544 outward along the relay pipe
546. Under this condition, the spring 547 is compressed and the
engaging projection 545 can be free from both the catch hole 533
and the through hole 543 such that the lock disk 544 can be rotated
eccentrically to lose joining movement with the driving wheel 53
and the driving wheel 53 becomes in a state of being no any traction.
Right at this time, the user can push the holding part and rotates
and moves two large wheels at the two lateral sides of the wheel
chair with the driving wheel being in an idle state and acting as
a following wheel.
[0019] With the help of the previous mentioned explanation, the
wheel chair can be assembled with DIY and become a finished product
as shown in FIG. 2. By controlling the switch installed on the handle
12, the driving wheel 53 can move forward and backward. When trying
to make a turn, the user just has to hold the handle 12 and rotate
it, which will make the driving wheel 53 in between the two front
wheels to turn as well. This shows how easy the wheel can be controlled.
[0020] Accordingly, by way of the implementation of the present
invention, an advantage thereof is that the present invention can
be associated with any of the available wheel chairs. Hence, the
transmission mechanism of the present invention can be popularized
in families, hospitals, old folk homes, or rehabilitation organizations
that already own the wheel chairs so that it is not necessary to
acquire the expensive electric movable wheel chair instead. Besides,
when the battery unit runs out of power, the manual device can be
adjusted to make the driving wheel free from actuating the lock
disk and becomes idle and the wheel chair is then resumed to the
original manual movement control by pushing with hands. Furthermore,
transmission mechanism of the present invention does not have complicated
gearbox and chair structure design, so that cost of production will
be greatly reduced and achieve the popularity and low cost goals
that the conventional electrical wheel chairs will never reach.
[0021] While the invention has been described with reference to
the a preferred embodiment thereof, it is to be understood that
modifications or variations may be easily made without departing
from the spirit of this invention, which is defined by the appended
claims. |