Note: Descriptions are shown in the official language in which they were submitted.
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CANE WITH EXTENDABLE/RETRACTABLE SPIKE
Field of the Invention
This invention relates in general to walking aids,
and more particularly to an adjustable length walking
cane with retractable spike.
Backqround of the Invention
Every year, hundreds of thousands of people,
including seniors and those with physical disabilities,
suffer severe injuries as a result of slipping on ice,
snow, wet grass, mud, leaves, etc. A large number of
such accidents have been known to occur even when a
person has been walking with a cane.
Prior art walking canes have been devised to address
the aforenoted problems. For example, United States
Patent 3,448,749 (Stark) discloses a cane with
retractable spikes connected to a finger operated
actuating lever via a pivot device. A similar device is
disclosed in United States Patent 2,682,275 (Eyrich)
wherein the spike is trigger operated and spring loaded.
In addition to the known prior art canes with retractable
spikes, adjustable length canes are also known. Such
canes normally are provided with a telescoping shaft with
aligned holes through the inner and outer shafts and
suitable fastening means such as a spring pin for
securing the telescoping tubes in predetermined
orientation to establish the length of the cane.
It is not believed to be known in the prior art to
provide a cane with both adjustable overall length, and
retractable spike or other ground engaging anti-slip
mechanism.
Summary of the Invention
According to the present invention, an adjustable
length cane is provided in combination with a trigger-
operated, internally disposed spike. The cane of the
present invention is characterized by an orthopedically
; shaped handle for placing the user's hand directly over
the weight supporting shaft to ensure balance and
comfort. The handle incorporates a plurality of
structural ribs for spreading the weight load on the
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handle and directing the load toward the centre of the
cane shaft. An ergonomically placed trigger is provided
for activating the internal spike mechanism so that when
the spike is activated the trigger lies flush with the
S handle. A novel internal structure is provided for
accommodating both overall length adjustment of the cane
in combination with the retractable spike function.
According to an aspect of the present invention,
there is provided an orthopaedic mobility assistance
device, comprising:
a) first support means;
b) handle means connected to said first support
means;
c) trigger means mounted to said handle means,
said trigger means being adapted to move selectively
between a first position and a second position,
d) second support means connected to said first
support means at one end and having a ground engaging
portion at opposite end for contacting a walking surface;
e) retractable spike means adapted for
selectively protruding from said ground engaging portion
to contact said walking surface with increased gripping
action than said ground engaging portion, and retracting
within said ground engaging portion when said increased
gripping action is not required; and
f) connecting means between said trigger means
and said retractable spike means for protruding said
spike means from said ground engaging portion in response
to said trigger means being moved to said first position
and retracting said spike means into said ground engaging
portion in response to said trigger means being moved to
said second position.
Brief Description of the Drawings
A detailed description of the preferred embodiment
is provided herein below with reference to the following
drawings, in which:
Figure 1 shows an adjustable length cane with
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retractable spikes in accordance with the preferred
embodiment;
Figure 2 is a detailed perspective view of the
handle portion of the cane with trigger retracted into
the handle portion;
Figure 3 is a detailed perspective view of a ground
engaging portion of the cane with projecting retractable
spike;
Figure 4 is a cross-sectional view of the cane
according to the preferred embodiment;
Figures 5A and 5B are detailed schematic views
showing operation of the trigger mechanism according to
the preferred embodiment;
Figures ~A and 6B are detailed cross-sectional views
showing a ground engaging portion of the cane and
operation of the retractable spike, according to the
preferred embodiment;
Figures 7A and 7B are detailed cross-sectional views
showing length adjusting means according to the present
invention; and
Fiqure 8 is a perspective view showing the structure
and operation of the retractable spike according to the
preferred embodiment.
Detailed Description of the Preferred Embodiment
The outward appearance of the height adjustable cane
according to the present invention is shown with
reference to Figures }-3. The cane comprises handle
portion 1 connected to a first support member 5. A
second support member 7 is secured in telescopic
: 30 arrangement with the first support member 5 and is
provided with a ground engaging portion 9 at the base
thereof. According to the preferred embodiment, the
ground engaging portion 9 comprises a rubber boot which
houses a retractable spike 11 (Figure 3). The
retractable spike 11 is operated by means of a trigger
mechanism 13 so that in the position shown in Figure 1,
the spike 11 is retracted within the ground engaging
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portion 9, and upon moving the trigger mechanism 13 into
the position shown from Figure 2, the spike 11 is caused
to project or protrude from the ground engaging portion
9. .
~ wrist strap 15 is provided for ease of carrying
the cane when climbing stairs, or for hanging the cane by
a coat peg, etc.
The handle portion 1 preferably comprises a first
generally oblong portion 17 oriented substantially
perpendicular to the first support member 5. A second
portion 19 of the handle 1 extends co-axially with the
first support member 5 and arcs slightly to a rounded
apex 21. A reduced diameter portion 23 is provided
intermediate the first generally oblong portion 17 and
the second portion 19. The reduced diameter portion 23
is positioned over the first support member 5.
Turning to Figures 4 and 8, the internal structure
of the cane is illustrated. Within the handle 1, a
triangulated rib structure is provided for spreading
weight load applied to the handle and directing the
weight load to the centre of the shaft of the cane.
Specifically, the internal supporting rib structure
comprises a central rib 25 extending from a distal end of
the first generally oblong portion 17 centrally
therethrough to a surface of the second portion 19
opposite the distal end. The second central rib 27
extends from a distal end of the second portion 19
adjacent the reduced diameter portion 23 centrally
through the second portion toward the first support
member 5. The first central rib 25 and the second
central rib 27 intersect perpendicularly at the focus of
the rounded apex 21. A plurality of additional ribs,
such as ribs 29, are connected to the first central rib
25 and the second central rib 27 so as to form triangles
therewith, triangular construction of supporting ribs
being stronger than rectangular or other geometric
structures.
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Connecting apparatus is provided between the trigger
13 and the retractable spike 11 for protruding the spike
from the ground engaging portion 9 in response to the
trigger 13 being moved from the position shown in Figure
5A to the position shown in Figure SB. According to the
preferred embodiment, this connecting apparatus comprises
an actuator rod 31 connected to the trigger 13 and a
cylindrical member 33 connected at one end to the rod 31
via a length adjusting threaded fitting 35, and at an
opposite end to the retractable spike 11.
As shown in Figures 4, SA and 5B, the trigger 13
comprises a generally C-shaped portion 36 connected at a
base portion thereof to the handle 1 via a first pivot or
hinge pin 37. An extension 39 projects from the base of
the C-shaped portion 36 on the opposite side of the first
pivot 37. A cantilever arm 41 is pivotally connected at
one end to the extension 39 via spring pin 43 and at an
opposite end to the actuator rod 31 via pivot 45.
As will be described in greater detail below, in
order to move the spike 11 into the protruded ground
engaging position of Figure 3, the C-shaped portion 36 of
trigger 13 is pulled via finger action upwardly from the
position shown in Figure 5A to the position shown in
Figure 5B. Conversely, in order to retract the spike 11
: 25 within the ground engaging portion 9, the trigger 13 is
pivoted from the position shown in Figure 5B to the
position shown in Figure 5A by applying downward pressure
on the distal end 38 of the C-shaped portion 36 of
trigger 13.
3~ In the position shown in Figure 5A, the trigger 13
is held in place by a resilient latch comprising a catch
mechanism 47 disposed within the second portion 19 of the
handle 1, and a cooperatively shaped finger projection 51
from the extension 39. The finger projection 51 is
adapted to be releasably received within the catch
mechanism 47.
Upon pulling the trigger 13, the trigger is caused
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to rotate about pivot 37, thereby causing cantilever arm
41 to move downwardly while pivoting about spring pin 43.
This causes the actuator rod to move downwardly within
the first supporting member S without any bending forces
being applied thereto via the trigger mechanism. The
actuator rod 31 further comprises a threaded rod 53 which
is connected to the rod 31 via force-fit engagement at a
lower end thereof.
The spike 11 is embedded into the lowermost portion
of the connection member 33, the threaded brass fitting
35 being embedded at an opposite distal end thereof. The
connecting member 33 may be fabricated from injection
molded plastic or other suitable material with a hollow
core running through opposite quonset-shaped molded
portions 54 for receiving the threaded rod 53.
Thus, the downward movement actuator rod 31 which is
responsive to moving the trigger 13 from the position
shown in Figure 5A to the position shown in Figure 5B,
causes a downward movement in connection member 33 which,
in turn, causes the spike 11 to protrude from the bottom
of the ground engaging portion 9.
In the spike-extended position of Figure 5B, the
trigger 13 is retracted so as to be flush with the handle
1, within a recess 55 (Figures 4 and 5B).
The injection molded cylindrical member 33 includes
a slot 57 for receiving an inwardly directed detent 59 in
the second tubular support member 7, as shown in detail
with reference to Figure 6A and 6B. In Figure 6A, the
; spike 11 is shown in the retracted position whereas in
Figure 6B, the spike 11 is shown protruding from the
ground engaging portion 9. In the retracted position of
Figure 6A, the cylindrical member 33 is raised so that
the detent 59 abuts the lower extremity of recess 57
while in Figure 6B, the cylindrical member 33 has moved
downwardly so that the detent 59 rests against an upward
- extremity of the slot or recess 57.
With reference to Figures 7A and 7B, the mechanism
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for adjusting the length of the cane is shown in greater
detail comprising a first aperture 61 in the second
support member 7, a plurality of further apertures 63 in
the first support member 5 and extending along a portion
5 of the length thereof, and a pin 65 for insertion through
a selected one of the plurality of apertures 63 and the
aperture 61 for securing the second support member 7 to
the first support member 5 against rotational and
longitudinal movement in a selected one of the plurality
10 of adjustable length positions.
A protective ring 8 is provided for covering and
concealing the height adjustment pin 65 (see Figure 1).
In order to adjust the length of the cane from the
position shown in Figure 7A to the position shown in
15 Figure 7B, the pin 65 is removed and the support member 7
is rotated counterclockwise relative to the support
member 5. The rotational movement of support member 7 is
translated to the inner connecting member 33 via the
detent 59 and internal recess or slot 57. The actuator
20 rod 31 and threaded rod 53 are prevented from rotating by
virtue of the rigid connection of trigger 13 to handle
portion 1. Therefore, counterclockwise rotation of the
connecting member 33 causes threaded brass bushing 35 to
advance along the threhds of stationary rod 53. Rotation
25 of the lower supporting member 7 is continued until the
aperture 61 aligns with the next lower one~ of the
apertures 63 in upper supporting member 5. Then, as
shown in Figure 713, the pin 65 is re-inserted through the
aligned holes for preventing further relative rotation
30 between the upper and lower supporting members 5 and 7.
The annular ring 71 surrounds actuator rod 31
(Figure 8) for preventing excessive flexing due to the
weight load on the rod 31.
Rotation of the lower support member or tube 7 in a
35 clockwise direction shortens the length of the cane by
retracting the lower supporting member 7 into the
surrounding upper supporting member 5. In all other
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respects, the procedure for shortening the length of the
cane is identical to the procedure discussed above in
connection with lengthening the cane.
In addition to the foregoing, according to the
preferred embodiment, vibration absorbing rings 67 are
provided intermediate the handle 13 and the first support
means 7 (Figure 4). Furthermore, a detent 69 is provided
in the upper end of lower support member 7 for
maintaining proper alignment between the first support
means 7 and cylindrical member 33.
In summary, a walking cane is provided with a
retractable spike 11 for aiding the user in walking
confidently over dry surfaces, hazardous ice, snow, wet
grass, mud or other surfaces. The orthopedically shaped
handle 1 provides greater user balance and fits both
small and large hands, including hands which suffer from
arthritis. The trigger may be easily reached and
activated using only one finger while walking and even
when wearing gloves. Both the handle 1 and completely
retractable trigger 13 are made from light and durable
material. The spike 11 may be completely retracted when
not in use, to prevent harm to carpeting or wooden
floors. The aluminum shaft of the cane provided by lower
tube 7 and upper tube 5 is completely height adjustable
to suit any person. The cane of the present invention
incorporates very few moving parts resulting in higher
reliability and low maintenance re~uirements.
Other variations and modifications of the invention
are possible. For example, the principle of height
adjustment and retractable spike as discussed herein may
be applied to crutches or other orthopaedic mobility
aiding devices. All such modifications or variations are
~` believed to be within the sphere and scope of the
invention as defined by the claims appended hereto.
