FIELD OF THE INVENTION
[0001] The present invention relates to an integral wheel rim for a wheelchair, and more
particularly, to an integral wheel rim with a hollow rib connected between the handle
portion and the wheel rim to reduce the weight and reinforce the strength.
BACKGROUND OF THE INVENTION
[0002] The conventional wheelchair for disable persons generally comprises a frame, a seat,
two armrests, two leg rests, two rims, a hand rim for each wheel, a brake unit and
a handle. The conventional wheelchair can be driven by electric power or by manual
way.
[0003] The sizes of the rims generally have 12 inches, 16 inches, 18 inches, 20 inches,
22 inches and 24 inches. For the manual operated wheelchair, the size of the rims
is over 24 inches so as to save the effort of the user. For the electric wheelchair,
the size of the rims is smaller so that the electric power easily drives the wheelchair
and the smaller rims are safe.
[0004] There is an hand rim attached to the rim so that the user can grasp the handle portion
to move the wheelchair forward or backward. The hand rim is integrally formed with
the rim, or is connected to the rim.
[0005] Taiwan Utility Model 098204096 discloses a rim with lugs extending laterally therefrom,
a tire is engaged with the insides of the lugs and an hand rim connected to the outside
of the rim. The hand rim is made by non-metallic material such as rubber or polymer
material. A connection portion extends from the inside of the hand rim and has an
engaging slot which is engaged with the lugs of the rim.
[0006] U.S. Patent No. 7,303,203 discloses a wheel for a wheelchair with a hand rim device comprised of a heat conducting
tubular hand rim and a continuous circumferential elastomeric interface that has a
cross-sectional contour comprised of an outwardly extending horizontal member having
a proximal end coupled to an outboard side of a wheel rim transitioning into a downwardly
depending member terminating to a distal end coupled to an inboard upper portion of
the tubular hand rim such that a majority of the tubular hand rim is exposed and devoid
of the elastomeric interface. When braking, a user only uses the heat conducting tubular
hand rim. When pushing, the user grips across both the tubular hand rim and the contoured
elastomeric interface, which deforms to fit the hand, thereby providing improved comfort,
frictional coupling, and impact attenuation.
[0007] U.S. Patent No. 7,204,506 discloses a wheel for a wheelchair and has a tire groove and a reinforcement device
which has a tube located on the inside of the tire groove. A hand rim is connected
to the wheel and a mediate portion connected between the reinforcement device and
the tire groove.
[0008] The wheels of the wheelchair cannot be too weight and the thickness and size of the
connection parts for connection between the wheel rim and the hand rim are limited.
The hand rim is co-rotated with the wheel and the user's force is applied to the hand
rim and the transferred to the wheel so that the connection parts between the hand
rim and the wheel rim have to be strong to bear the torque. Furthermore, the connection
parts have to bear the force applied along the tangential direction of the hand rim.
[0009] The connection part of the integral hand rim is solid but has thin thickness which
cannot increase the force transferring feature and the thin thickness may be deformed
when a large torque is applied. When the wheel of the wheelchair receives an impact,
the wheel rim may be broken to injure the user. Besides, the solid connection part
does not buffer the impact and the user feels discomfort after operating for a period
of time.
[0010] The present invention intends to provide an integral rim for a wheelchair and the
integral rim improves the shortcomings mentioned above.
SUMMARY OF THE INVENTION
[0011] The present invention relates to an integral wheel rim for a wheelchair and comprises
a wheel rim and a groove is integrally defined in the outer periphery of the wheel
rim and a tire is engaged with the groove. A flange extends inward and radially from
the inner periphery of the wheel rim and has a first hollow portion. A hand rim is
located parallel to the wheel rim and integrally formed with the wheel rim. The hand
rim has a palm portion and a finger portion, wherein the palm portion is located on
the outer periphery of the hand rim and the finger portion is located on the inner
periphery of the hand rim. The palm portion and the finger portion enclose a second
hollow portion. A hollow rib is connected between the wheel rim and the hand rim.
The hollow rib is composed by an inner wall and an outer wall. The inner and outer
walls is separated from each other. A hollow area is defined between the inner and
outer walls and communicates with the first and second hollow portions. The outer
wall has a handle portion on the outer surface thereof for being touched by the user's
hand. The hollow rib is connected between the hand rim and the wheel rim so as to
absorb the impacts from the ground and is reinforced by the thicker thickness.
[0012] The primary object of the present invention is to provide an integral wheel rim and
a hollow rib is connected between the wheel rim and the hand rim. The thickness of
the hollow rib is increased to reinforce the strength.
[0013] Another object of the present invention is to provide an integral wheel rim and the
hollow rib can absorb the impacts from the ground.
[0014] Yet another object of the present invention is to provide an integral wheel rim wherein
the hollow rib is composed of the inner wall and the outer wall so as to efficiently
transfer force to the wheel rim and reduce the weight.
[0015] The present invention will become more obvious from the following description when
taken in connection with the accompanying drawings which show, for purposes of illustration
only, a preferred embodiment in accordance with the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016]
Fig. 1 is a perspective view to show the wheel rims of the present invention connected
to a wheel chair;
Fig. 2 is a perspective view to show the wheel rim of the present invention;
Fig. 3 is a cross sectional view of the wheel rim of the present invention;
Fig. 4 is a cross sectional view of the second embodiment of the wheel rim of the
present invention;
Fig. 5 is a cross sectional view of the third embodiment of the wheel rim of the present
invention;
Fig. 6 is a perspective view to show the fourth embodiment of the wheel rim of the
present invention;
Fig. 7 is a cross sectional view of the fourth embodiment of the wheel rim of the
present invention;
Fig. 8 is a perspective view to show the fifth embodiment of the wheel rim of the
present invention;
Fig. 9 is a cross sectional view of the fifth embodiment of the wheel rim of the present
invention;
Fig. 10 is a perspective view to show the sixth embodiment of the wheel rim of the
present invention;
Fig. 11 is a cross sectional view of the sixth embodiment of the wheel rim of the
present invention, and
Fig. 12 is a partial perspective view to show the seventh embodiment of the wheel
rim of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] Referring to Figs. 1 to 3, the wheel rim 10 of the present invention comprises a
wheel rim 10 and a hand rim 20 is located parallel to the wheel rim 10. A hollow rib
30 is connected between the wheel rim 10 and the hand rim 20.
[0018] The wheel rim 10 is a ring-shaped rim and a groove 11 is integrally defined in the
outer periphery of the wheel rim 10. The groove 11 is an open groove and a tire 50
is engaged with the groove 11. A flange 12 extends inward and radially from the inner
periphery of the wheel rim 10 and has a first hollow portion 13 such that spokes (not
shown) are connected to the inner periphery of the flange 12.
[0019] The hand rim 20 is parallel to the wheel rim 10 and integrally formed with the wheel
rim 10. The hand rim 20 is a ring-shaped rim and has a palm portion 21 and a finger
portion 22. The palm portion 21 is integrally formed on the outer periphery of the
hand rim 20 and the finger portion 22 is integrally formed on the inner periphery
of the hand rim 20. The palm portion 21 and the finger portion 22 enclose a second
hollow portion 23.
[0020] The hollow rib 30 is connected between the wheel rim 10 and the hand rim 20. The
hollow rib 30 is composed by an outer wall 31 and an inner wall 32. The inner and
outer walls 32, 31 are separated from each other at a pre-set distance. A hollow area
33 is defined between the inner and outer walls 32, 31 and two sides of the hollow
area 33 communicates with the first and second hollow portions 13, 23 respectively.
The outer wall 31 has a handle portion 34 on the outer surface thereof and the handle
portion 34 has a curved and recessed surface so as to be grasped or touched by the
user's hand.
[0021] The hollow rib 30 is connected between the hand rim 20 and the wheel rim 10 so as
to absorb impacts from the ground and the hollow rib 30 is reinforced by the thicker
thickness which prevents the hollow rib 30 from being formed. The hollow rib 30 also
reduces the weight of the wheel rim 10.
[0022] As shown in Fig. 3, the groove 11, the flange 12, the palm portion 21, the finger
portion 22 and the inner and outer walls 32, 31 are integral to the wheel rim 10.
The two sides of the inner and outer walls 32, 31 are respectively connected to the
wheel rim 1 and the hand rim 20. The inner wall 32 is connected between the flange
12 and the palm portion 21, and the outer wall 31 is connected between the flange
12 and the finger portion 22. The hollow area 33 is defined between the inner and
outer walls 32, 31. The palm portion 21 and the finger portion 22 defined the second
hollow portion 23. The first and second hollow portions 13, 23 and the hollow area
33 are in communication with each other such that when manufacturing the wheel rim
10, the groove 11, the flange 12, the palm portion 21, the finger portion 22 and the
inner and outer walls 32, 31 are easily formed.
[0023] The groove 11 is defined in the outer wall 31 and the outer wall 31 has the handle
portion 34 on the outer surface thereof. When the user holds the hand rim 20, the
palm touches the palm portion 21 and the handle portion 34, and the fingers touch
the finger portion 22. The sizes and curvatures of the palm portion 21, the handle
portion 34 and the finger portion 22 can be adjusted as needed.
[0024] The hollow rib 30 is integrally connected between the wheel rim 10 and the hand rim
20 so as to reduce the weight of the wheel rim 10. The distance between the inner
and outer walls 32, 31 is increased and the thickness of the hollow rib 30 is increased
to reinforce the strength so as to prevent from being broken or deformed.
[0025] The first and second hollow portions 13, 33 and the hollow area 33 impede the impacts
from the ground to be transferred to the user. This makes the user feel comfortable
when compared with the solid wheel rim. The first and second hollow portions 13, 33
and the hollow area 33 also absorb vibration.
[0026] The inner and outer walls 32, 31 of the hollow rib 30 splits the push force into
two portions which are more efficiently transferred to the wheel rim. The design allows
the user to more easily operate the wheel rim 10.
[0027] The hollow rib 30 has thicker thickness which reduces the material required and saves
manufacturing cost.
[0028] The hollow rib 30 reduces the weight of the wheel chair when compared with the solid
wheel rim.
[0029] As shown in Fig. 4, the second embodiment of the present invention provides a reinforcement
rib 35 is integrally connected between the inner and outer walls 32, 31. The reinforcement
rib 35 divides the hollow area 33 into two spaces 331, 332. The reinforcement rib
35 can be made during manufacturing processes.
[0030] The reinforcement rib 35 reinforces the strength of the hollow rib 30.
[0031] Fig. 5 shows the third embodiment, wherein a reinforcement rib 14 is located in the
first hollow portion 13 and integrally connected to the inner periphery of the flange
12. The reinforcement rib 14 divides the first hollow portion 13 into two spaces 131,
132. A reinforcement rib 24 is located in the second hollow portion 23 and divides
the second hollow portion 23 into two spaces 231, 232. The two reinforcement ribs
14, 24 can be made during manufacturing processes.
[0032] The two reinforcement ribs 14, 24 reinforce the strength of the wheel rim 10 and
the hand rim 20.
[0033] Figs. 6 and 7 show the fourth embodiment, wherein two reinforcement ribs 35 are integrally
and respectively connected between the inner and outer walls 31, 32. The reinforcement
ribs 35 are located on two sides of the hollow rib 30 and separate the hollow area
33 and the first and second hollow portions 13, 23.
[0034] The two reinforcement ribs 35 reinforce the hollow rib 30. Although the first and
second hollow portions 13, 23 do not communicate with the hollow area 33, the embodiment
still have better shock-absorbing feature than the conventional wheel rim.
[0035] Figs. 8 and 9 show the fifth embodiment, wherein a reinforcement rib 14 is connected
in the first hollow portion 13 and divides the first hollow portion 13 into two spaces
131, 132. The reinforcement rib 14 is integrally connected to the inner periphery
of the flange 12 and perpendicular to the flange12. The finger portion 22 has a serrated
anti-slip portion 221 which has multiple ridges on the outer periphery of the finger
portion 22. The ridges, the reinforcement rib 14 and the anti-slip portion 221 are
made during manufacturing processes.
[0036] The anti-slip portion 221 increase friction when the user holds the wheel rim 10
and the reinforcement rib 14 increases the strength of the wheel rim 10.
[0037] Figs. 10 and 11 show the sixth embodiment, wherein the hollow rib 30 has multiple
holes 36 defined through the inner and outer walls 32, 31. The palm portion 21 has
another serrated anti-slip portion 211. The serrated anti-slip portion 211 comprises
multiple bosses which are located on the outer periphery of the palm portion 21. The
holes 36 are machined after the groove 11, the flange 12, the palm portion 21, the
finger portion 22 and the inner and outer walls 32, 31 are made.
[0038] The anti-slip portion 211 increase friction when the user holds the wheel rim 10.
[0039] Fig. 12 shows the seventh embodiment, wherein the finger portion 22 has multiple
curved recesses 222 defined in the outer periphery thereof and the curved recesses
222 can be made during the manufacturing processes.
[0040] The multiple curved recesses 222 are designed to accommodate the user's fingers which
operate the wheel rim 10 in the tangential direction and the curved recesses 222 provide
the fingers a support position to operate the wheel rim 10.
[0041] While we have shown and described the embodiment in accordance with the present invention,
it should be clear to those skilled in the art that further embodiments may be made
without departing from the scope of the present invention.
1. An integral wheel rim for a wheelchair comprising:
a wheel rim being a ring-shaped rim and a groove integrally defined in an outer periphery
of the wheel rim, a tire engaged with the groove, a flange extending inward and radially
from an inner periphery of the wheel rim and having a first hollow portion;
a hand rim located parallel to the wheel rim and integrally formed with the wheel
rim, the hand rim being a ring-shaped rim and having a palm portion and a finger portion,
the palm portion located on an outer periphery of the hand rim and the finger portion
located on an inner periphery of the hand rim, the palm portion and the finger portion
enclosing a second hollow portion, and
a hollow rib connected between the wheel rim and the hand rim, the hollow rib composed
by an inner wall and an outer wall, the inner and outer walls being separated from
each other, a hollow area defined between the inner and outer walls and communicating
with the first and second hollow portions, the outer wall having a handle portion
on an outer surface thereof for being touched by the user's hand.
2. The wheel rim as claimed in claim 1, wherein the handle portion has a curved and recessed
surface, the palm portion has a curved protruding surface, and the finger portion
has a curved protruding surface.
3. The wheel rim as claimed in claim 1, wherein at least one reinforcement rib is integrally
connected between the inner and outer walls, the at least one reinforcement rib divides
the hollow area into at least two spaces.
4. The wheel rim as claimed in claim 1, wherein at least one reinforcement rib is located
in the first hollow portion and integrally connected to an inner periphery of the
flange, the at least one reinforcement rib divides the first hollow portion into at
least two spaces.
5. The wheel rim as claimed in claim 1, wherein at least one reinforcement rib is located
in the second hollow portion and integrally connected to an inner periphery of the
hand rim, at least one reinforcement rib divides the second hollow portion into at
least two spaces.
6. The wheel rim as claimed in claim 1, wherein the finger portion has a serrated anti-slip
portion and the palm portion has another serrated anti-slip portion.
7. The wheel rim as claimed in claim 6, wherein the serrated anti-slip portion comprises
multiple ridges which are located on an outer periphery of the finger portion.
8. The wheel rim as claimed in claim 6, wherein the serrated anti-slip portion comprises
multiple bosses which are located on an outer periphery of the palm portion.
9. The wheel rim as claimed in claim 1, wherein the hollow rib has multiple holes defined
through the inner and outer walls.
10. The wheel rim as claimed in claim 1, wherein the finger portion has multiple curved
recesses defined in an outer periphery thereof.