[0001] The present invention relates to a crutch.
[0002] For those who are handicapped in their lower limbs, the crutch is a vital and indispensable
instrument which they cannot leave even for a moment in their daily lives.
[0003] The most serious problem common to all crutched persons resides in the trouble concerning
the disposal or storage of the crutch when it is not used, rather than the difficulty
in the handling of the same for the walking or the like purposes.
[0004] Unfortunately, the modern society is leaning to exclude the crutches in its all aspects.
Thus, the crutches are becoming hardly accepted.
[0005] Accordingly the present invention provides a crutch comprising an elongated upper
portion (1), an elongated lower portion (2), connecting means for pivotally connecting
the adjacent ends of said upper and lower portions to each other, and locking means
(10) adapted to lock said upper and lower portion against pivotal movement, in such
a stretched state that said lower portion is linearly extended from said upper portion.
[0006] It is therefore an advantage of the invention that a crutch is provided which can
conveniently be folded into a short length when not in use.
[0007] It is another feature of the invention to provide a crutch having an upper and a
lower portions which are pivotally secured to each other for a 180
0 rotation.
[0008] It is still another feature of the invention to provide a crutch having a mechanism
for locking the upper and lower portions against the relative pivotal movement when
the crutch is to be presented for use.
[0009] It is a further feature of the invention to provide a crutch having a locking mechanism
which can be handled without difficulty.
[0010] These and other objects, as well as advantageous features of the invention, will
become more clear from the following description of preferred embodiments taken in
conjunction with the accompanying drawings in which:
Figure 1 is a front elevational view of a crutch in accordance with the invention,
Figure 2 is a side elevational view of the crutch as shown in Figure 1,
Figure 3 is a side elevational view of the crutch in the folded state,
Figure 4 is a front elevational view of the crutch in the folded state,
Figure 5 is an enlarged perspective view of the crutch in the locked state, specifically
showing the connecting portion of the upper and lower parts of the crutch,
Figure 6 is an enlarged perspective view of the crutch in the unlocked and slightly
folded state, specifically showing the same portion as that shown in Figure 5,
Figure 7 is an enlarged perspective view of the connecting portion with the constituents
of the locking mechanism removed,
Figure 8 is an exploded perspective view of the locking mechanism, showing the constituents
of the same, and
Figure 9 is a sectional view taken along the line IX-IX of Figure 5.
[0011] Referring to the drawings, a crutch embodying the present invention has an upper
portion 1 and a lower portion 2 of substantially equal lengths. The upper portion
1 is provided with a handle or a hand-retaining bar 3. The lower end of the upper
portion 1 has a pair of forked or U-shaped portions la. Each U-shaped portion la has
a groove lb extending in the longitudinal direction of the upper portion 1 and at
a right angle to the breadthwise direction of the latter.
[0012] On the other hand, the lower portion 2 is provided with a pair of projections 2a
formed on its upper end. These projections 2a are received by the grooves lb of corresponding
U-shaped portions la.
[0013] As will be seen most clearly from Figure 7, the U-shaped portion la and the projection
2 have lateral extensions which are shown, in Figure 7, to project downwardly from
the upper and lower portions 1, 2. Mutually aligned through bores 4 are formed in
these lateral extensions of the U-shaped portions la and the projections 2a.
[0014] The common axis X-X of the through bores 4 extends in the breadthwise direction of
the crutch and at a right angle to the longitudinal axis of the crutch.
[0015] As will be seen from Figure 2, the centre X of the through bore 4 is slightly deviated
outwardly from the side edges lc, 2c of the upper and lower portions 1, 2 of the crutch.
[0016] The upper portion 1 and the lower portion 2 are pivotally connected to each other
through a rod 5 which is inserted into the through bores 4. Thus, the lower portion
2 can be swung by 180° around the axis of the rod 5, from the folded position as shown
in Figures 3, 4 in which it extends in parallel with the upper portion 1 to the stretched
position as shown in Figures 1, 2 in which it is linearly extended from the upper
portion 1.
[0017] The arrangement is such that the ends ld of each U-shaped portion la abut shoulders
2d formed at both sides of each projection 2a, when the lower portion 2 is rotated
by 180° into the stretched position, thereby to prevent the lower portion 2 from being
further rotated

[0018] Guide pipes 9 are fixed to the opposing surfaces of two U-shaped portions la, la,
in axial alignment with respective locking bores 7. Each guide pipe 9 slidably holds
a locking pin 10. Each locking pin 10 is fixed to an operation plate 11. These operation
plates 11 are fixed to respective pipes 12 which are slidable along the rod 5. A collar
13 is fixed by suitable means to the centre of the rod 5. A coiled spring 14 is disposed
on each side of the collar 13. These coiled springs 14 are adapted to bias respective
operation plates toward the corresponding U-shaped portions la, so as to drive the
locking pins into the locking bores 7, 8. Two operation plates 11, 11 are spaced apart
from each other by such a distance that these operation plates can easily be brought
together by fingers of single hand.
[0019] In use, the lower portion 2 of the crutch in accordance with the invention is locked
at the stretched position as shown in Figures 1 and 2, with the locking pins 10 received
by corresponding locking bores as shown in Figure 5.
[0020] For folding the crutch, two operation plates 11, 11 are brought together by fingers
as shown in Figure 6, so that the locking pins 10, 10 may be disengaged at least from
the locking bores 8, 8. Then, the lower portion 2 is simply pivoted with respect to
the upper portion 1 to the folded position as shown in Figures 3, 4.
[0021] Since the length of the crutch is reduced to half by the folding, the crutch in the
folded state can be handled quite easily and can conveniently be stored even in an
extremely limited space.
[0022] Further, the folded crutch can support itself and, therefore, can conveniently be
used as a temporary stool, by flattening the lower end of the crutch in the folded
state as shown in Figure 3.
[0023] Thus it can be seen that the invention provides a crutch which can be readily manufactured
and which will serve a useful purpose for those people who have need of a crutch.
1. A crutch comprising: an elongated upper portion (1); an elongated lower portion
(2); connecting means for pivotally connecting the adjacent ends of said upper and
lower portions to each other; and locking means (10) adapted to lock said upper and
lower portions against pivotal movement, in such a stretched state that said lower
portion is linearly extended from said upper portion.
2. A crutch as claimed in Claim 1, wherein said upper and lower portions have substantially
equal lengths.
3. A crutch as claimed in Claim 1 or 2, wherein said connecting means has a pivot
axis around which said upper and lower portions are pivoted in relation to each other,
said pivot axis extending substantially in the breadthwise direction of said crutch
and substantially at a right angle to the longitudinal axis of said crutch.
4. A crutch as claimed in Claim 1, 2 or 3 including stop means (ld, 2d) adapted to
prevent said upper portion from being rotated beyond 180° around said pivot axis in
relation to said lower portion.
5. A crutch as claimed in Claim 1, 2, 3 or 4 wherein said connecting means comprises
a pair of U-shaped portions (la) formed at the end of either one of said upper and
lower portions, a pair of projections (2a) formed at the end of the other of said
upper and lower portions, said projections each being received between the legs of
a respective one of the U-shaped portions, there being aligned pivot bores formed
through said U-shaped portions and said projections, and a pivot rod (5) extending
through each of said through bores.
6. A crutch as claimed in Claim 5, wherein said locking means comprises a first locking
bore formed in at least one of said U-shaped portions (la), a second locking bore
formed in the respective one of said projections (2a) and a locking pin (10) arranged
to be inserted in said first and second locking bores.
7. A crutch as claimed in Claim 6, wherein said locking means comprises a locking
bore formed in each of said U-shaped portions (la), a second locking bore formed in
the respective projections (2a), and a pair of locking pins (10) each of which is
adapted to be inserted into a respective one of said first locking bores and associated
second locking bores.
8. A crutch as claimed in Claim 7 wherein said locking means comprises a pair of operating
plates (11) slidably mounted on said pivot rod (5), between said pair of said U-shaped
portions (la), each operating plate (11) being rigidly connected to a respective one
of said locking pins (10).
9. A crutch as claimed in Claim 7 or 8, wherein said locking means comprises a pair
of guides (9) secured on the opposing surfaces of said pair of said U-shaped portions
(la) in axial alignment with said locking bores to guide the respective locking pins
(10).
10. A crutch as claimed in Claim 8 or 9, wherein each said locking pin (10) is provided
with means (14) biassing it into its associated locking bores.
11. A crutch as claimed in Claim 10, wherein said biassing means (14) is operable
on the respective rod (10) by way of its operating plate (11).
12. A crutch as claimed in Claim 10 or 11, wherein said biassing means includes a
collar (13) secured on said pivot rod (5) between said operating plates (11) and a
pair of coiled springs (14) each disposed between said collar (13) and one of said
operating plates (11).