U.S. patent application number 11/734229 was filed with the patent office on 2007-08-09 for folding chair cot for use with emergency vehicles.
Invention is credited to Tad Clark, Nathan R. Walkinshaw, Mark Wenzel.
Application Number | 20070182220 11/734229 |
Document ID | / |
Family ID | 39864774 |
Filed Date | 2007-08-09 |
United States Patent
Application |
20070182220 |
Kind Code |
A1 |
Walkinshaw; Nathan R. ; et
al. |
August 9, 2007 |
Folding Chair Cot For Use With Emergency Vehicles
Abstract
The present invention relates to a collapsible emergency vehicle
chair cot that includes a support system and a movement system. The
support system is a retractable system disposed on the bottom of
the cot to support the chair cot during transportation. For
example, one embodiment of a support system includes a track that
extends from the bottom for the chair cot. The track supports the
chair cot thereby minimizing the need for an emergency worker to
manually support the chair cot during transportation. The movement
system is coupled to the support system and utilizes rotational
movement to assist in moving the chair cot over a surface. For
example, one embodiment of a movement system includes coupling a
motor system and a brake system to the support system to provide
motorized movement. The support system and movement system are
configured to be collapsible to facilitate using the chair cot with
an emergency vehicle. The chair cot further includes at least two
platforms for supporting a patient in a seated position.
Inventors: |
Walkinshaw; Nathan R.;
(Bountiful, UT) ; Clark; Tad; (Midvale, UT)
; Wenzel; Mark; (Sandy, UT) |
Correspondence
Address: |
KIRTON AND MCCONKIE
60 EAST SOUTH TEMPLE,
SUITE 1800
SALT LAKE CITY
UT
84111
US
|
Family ID: |
39864774 |
Appl. No.: |
11/734229 |
Filed: |
April 11, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11062646 |
Feb 22, 2005 |
|
|
|
11734229 |
Apr 11, 2007 |
|
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|
Current U.S.
Class: |
297/118 |
Current CPC
Class: |
A61G 1/013 20130101;
A61G 1/017 20130101; A61G 1/0268 20130101; A61G 1/0218 20130101;
A61G 1/0287 20130101; A61G 1/0237 20130101; A61G 1/0281 20130101;
A61G 1/0225 20130101 |
Class at
Publication: |
297/118 |
International
Class: |
A47C 13/00 20060101
A47C013/00 |
Claims
1. A chair cot configured for use with an emergency vehicle,
comprising: at least two platforms for supporting a patient in a
seated position during transportation; a support system coupled to
the at least two platforms configured to support the at least two
platforms during transportation; and wherein the support system is
configured to substantially collapse when positioned within the
emergency vehicle; a removable spinal immobilization surface for
supporting a patient in a supine spinally-immobilized position
during transportation, and configured to attach to the support
system when the support system is substantially collapsed; a
movement system coupled to the support system that is configured to
allow the chair cot to move over a surface, wherein the movement
system includes a motor; and a control system coupled to the
movement system that allows one or more individuals to control the
operation of the movement system.
2. The chair cot of claim 1, wherein the support system includes an
active or passive suspension system for minimizing impacts on a
patient during transportation by means of vibration absorption
through a track or through an active gas/spring system.
3. The chair cot of claim 1, wherein the motor is electric
functioning on alternating or direct current and further includes a
power source.
4. The chair cot of claim 3, wherein the power source is a
replaceable rechargeable battery.
5. The chair cot of claim 1, wherein the support system includes
two tracks that extend below the cot.
6. The chair cot of claim 5, wherein the two tracks include
protruding ribs to allow for gripping stairs and other irregular
surfaces.
7. The chair cot of claim 1, wherein the control system includes a
passive or active braking system that steers, slows, and stops the
rotational movement of the movement system when engaged, and that
locks in the event that power is lost.
8. The chair cot of claim 1, wherein the control system includes a
forward and reverse mechanism that allows the movement system to
move forward and reverse respectively.
9. The chair cot of claim 1, wherein a motorized portion of the
movement system can be disengaged thereby allowing for descent or
ascent of an inclined or declined surface utilizing non-motorized
rotational movement.
10. A chair cot configured for use with an emergency vehicle and
further configured for selective transitioning between powered use
on stairs and non-powered rolling on flat surfaces, comprising: an
adjustable back support for supporting a patient in a seated
position during transportation; an adjustable seat for supporting a
patient in a seated position during transportation; a support
system coupled to the back support and the seat and configured to
support the back support and the seat during transportation,
wherein the support system is configured to substantially collapse
when positioned within the emergency vehicle; a movement system
coupled to the support system that is configured to allow the chair
cot to move over a surface, wherein the movement system comprises:
a motor; a continuous track; casters; and retractable wheels,
wherein the retractable wheels are configured to have: a deployed
position whereby the retractable wheels and the casters engage a
flat surface and hold the continuous track away from the flat
surface such that the continuous track does not engage the flat
surface; and a stowed position whereby the continuous track engages
a flat, inclined, or stepped surface to move the chair cot; and a
control system coupled to the movement system that allows one or
more individuals to control the operation of the movement
system.
11. The chair cot of claim 10, wherein the retractable wheels are
further configured to automatically transition between the deployed
position and the stowed position as the chair cot encounters and
climbs stairs.
12. The chair cot of claim 10, wherein the support system
comprises: a back support hydraulic or pneumatic cylinder
configured to permit free adjustment of the back support between a
fully expanded configuration and a fully collapsed configuration;
and a seat hydraulic or pneumatic cylinder configured to permit
free adjustment of the seat between a fully expanded configuration
and a fully collapsed configuration.
13. The chair cot of claim 10, wherein the back support comprises a
disposable back surface and a means for securing the disposable
back surface to the chair cot and the seat comprises a disposable
seat surface and a means for securing the disposable seat surface
to the chair cot.
14. The chair cot of claim 13, wherein the means for securing the
disposable back surface to the chair cot and the means for securing
the disposable seat surface to the chair cot comprise indexing
pins, indexing receptacles, and magnets.
15. The chair cot of claim 13, wherein the means for securing the
disposable back surface to the chair cot and the means for securing
the disposable seat surface to the chair cot comprise a hook and
loop fastener system.
16. The chair cot of claim 13, wherein the disposable back surface
and the disposable seat surface include plastic.
17. A disposable patient surface for use with medical transport
equipment that can be used a single time and then disposed of and
billed to a patient as a consumable comprising: a support surface
configured to support a body part of the patient during medical
transport; and means for reversibly securing the support surface to
the medical transport equipment during transport, wherein the means
for reversibly securing the support surface to the medical
transport equipment holds the support surface in a proper position
relative to the medical transport equipment.
18. The disposable patient surface of claim 17, wherein the support
surface comprises a plastic, and the means for reversibly securing
the support surface to the medical transport equipment comprises
indexing receptacles on the support surface, indexing pins on the
medical transport equipment, and magnets on at least one of the
support surface and the medical transport equipment.
19. The disposable patient surface of claim 18 wherein the
polypropylene is customized with a logo representing a provider of
medical transport services.
20. A continuous track for use with a motorized stair climbing
device, comprising: a tread layer having a durometer between 60A
and 70A and comprising teeth sized and spaced so as to engage the
repeating steps of a stairway; a fiber layer providing strength to
the continuous track and bonded to the tread layer; and a drive
layer having a durometer between 80A and 55D and comprising teeth
sized and spaced so as to engage and transfer power from a drive
gear to the continuous track.
21. The continuous track of claim 20 wherein the teeth of the tread
layer comprise a flattened top and a valley, and wherein: the
height of the teeth of the tread layer from the flattened top to
the valley is between 0.54 inches and 0.66 inches; and the teeth of
the tread layer may have a tooth-to-tooth spacing of between 1.51
inches and 1.84 inches.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and is a
continuation-in-part of U.S. patent application Ser. No.
11/062,646, filed Feb. 22, 2005, entitled Folding Chair Cot for Use
with Emergency Vehicles, and naming Nathan R. Walkingshaw as the
inventor.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a cot, and in particular to
a collapsible emergency vehicle chair cot including a support
system and a movement system.
[0004] 2. Background
[0005] Cots are used to transport incapacitated or injured
individuals from one location to another. For example, EMTs
typically transport emergency medical patients from one location
into their ambulances using cots. Early cots merely consisted of
cloth stretched between two poles. A patient was positioned on the
cloth and two emergency workers carried either end of the poles,
thereby supporting the patient. The primary problem with this
design is that it requires two emergency workers to use both of
their hands to transport their patient. This is problematic because
emergency workers typically carry equipment and may need to perform
tasks on the patients while being transported. Later, wheels were
added to rigid cots to make gurneys which are easier for emergency
workers to move patients from a particular location into an
emergency vehicle. These added wheels allowed patients to easily be
wheeled across flat surfaces to an emergency vehicle. The added
wheels are also configured to collapse such that the cot could be
properly fitted into an emergency vehicle and serve as a bed during
transportation to a hospital. Additional wheels were eventually
added to the loading end of cots in order to minimize friction and
facilitate wheeling the cot into an emergency vehicle.
[0006] While these wheeled gurney embodiments provide significant
advantages over the traditional cloth-type cots, there are still
significant problems. For example, if the patient must be
transported over uneven surfaces such as stairs, curbs, or
inclines, the conventional wheeled gurney will still require at
least two emergency workers to properly transport the patient. In
addition, on steep and irregular inclines, it is very difficult to
support and stabilize the uphill side of the wheeled cot because it
will be disposed very close to the ground. Further, certain uneven
surfaces may cause the cot to bounce or shift resulting in
additional pain and possibly injury to the patient. Therefore, for
at least these reasons there is a need in the industry for an
improved cot.
BRIEF SUMMARY OF THE INVENTION
[0007] The present invention relates to a collapsible emergency
vehicle chair cot that includes a support system and a movement
system. The support system is a retractable system disposed on the
bottom of the cot to support the chair cot during transportation.
For example, one embodiment of a support system includes a track
that extends from the bottom for the chair cot. The track supports
the chair cot thereby minimizing the need for an emergency worker
to manually support the chair cot during transportation. The
movement system is coupled to the support system and utilizes
rotational movement to assist in moving the chair cot over a
surface. For example, one embodiment of a movement system includes
coupling a motor system and a brake system to the support system to
provide motorized movement. The support system and movement system
are configured to be collapsible to facilitate using the chair cot
with an emergency vehicle. The chair cot further includes at least
two platforms for supporting a patient in a seated position.
[0008] These and other features and advantages of the present
invention will be set forth or will become more fully apparent in
the description that follows and in the appended claims. The
features and advantages may be realized and obtained by means of
the instruments and combinations particularly pointed out in the
appended claims. Furthermore, the features and advantages of the
invention may be learned by the practice of the invention or will
be obvious from the description, as set forth hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0009] The accompanying drawings illustrate various embodiments of
the present invention and are a part of the specification. The
illustrated embodiments are merely examples of the present
invention and do not limit the scope of the invention.
[0010] FIG. 1A is a profile view of a chair cot in accordance with
one embodiment of the present invention;
[0011] FIG. 1B is a detailed view of the control system illustrated
in FIG. 1A;
[0012] FIG. 1C is a detailed view of the collapsing mechanism
attached to the arm rest illustrated in FIG. 1A;
[0013] FIG. 1D is a front view of the chair cot illustrated in FIG.
1A;
[0014] FIG. 2A is a profile view of an alternative embodiment of an
expanded chair cot in accordance with the present invention;
[0015] FIG. 2B is a profile view of the chair cot illustrated in
FIG. 2A in a collapsed configuration;
[0016] FIG. 2C is a front view of the expanded chair cot
illustrated in FIG. 2A;
[0017] FIG. 2D is a perspective view of the expanded chair cot
illustrated in FIG. 2A;
[0018] FIG. 3A is a perspective view of an alternative embodiment
of an expanded chair cot in accordance with the present
invention;
[0019] FIG. 3B is a profile view of the expanded chair cot
illustrated in FIG. 3A;
[0020] FIG. 3C is profile view of the chair cot illustrated in FIG.
3A in a collapsed configuration;
[0021] FIG. 4 is a perspective view of an alternate embodiment of a
chair cot in a collapsed position;
[0022] FIG. 5 is a perspective view of the chair cot illustrated in
FIG. 4 in an expanded position;
[0023] FIG. 6 is a perspective view of the chair cot illustrated in
FIG. 4 in an expanded position;
[0024] FIG. 7 is a detailed perspective view of a hydraulic release
element from the chair cot illustrated in FIG. 4; and
[0025] FIGS. 8A-8E are plan and perspective views of an embodiment
of a continuous track for use with embodiments of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0026] Reference will now be made to the drawings to describe
embodiments of the invention. It is to be understood that the
drawings are diagrammatic and schematic representations of the
embodiments, and are not limiting of the present invention, nor are
they necessarily drawn to scale.
[0027] The present invention relates to a collapsible emergency
vehicle chair cot that includes a support system and a movement
system. The support system is a retractable system disposed on the
bottom of the cot to support the chair cot during transportation.
For example, one embodiment of a support system includes a track
that extends from the bottom for the chair cot. The track supports
the chair cot thereby minimizing the need for an emergency worker
to manually support the chair cot during transportation. The
movement system is coupled to the support system and utilizes
rotational movement to assist in moving the chair cot over a
surface. For example, one embodiment of a movement system includes
coupling a motor system and a brake system to the support system to
provide motorized movement. The support system and movement system
are configured to be collapsible to facilitate using the chair cot
with an emergency vehicle. The chair cot further includes at least
two platforms for supporting a patient in a seated position. Also,
while embodiments of the present invention are directed to
emergency vehicle chair cots, it will be appreciated that the
teachings of the present invention are applicable to other
fields.
[0028] The following terms are defined as follows:
[0029] "chair cot"--a device for transporting an individual in a
sitting position from one location to an emergency vehicle. A chair
cot may be configured to interface with a gurney for use in a
hospital.
[0030] "gurney"--a wheelable bed device used in hospitals and other
facilities to easily transport patients over flat surfaces.
[0031] "emergency vehicle"13 any vehicle used to transport
incapacitated individuals from one location to another including
but not limited to ambulances, fire truck/engine, elderly car
vehicles, helicopter, etc.
[0032] "patient"--any person or animal being carried by a cot,
including but not limited to individuals and animals that are sick,
elderly, injured, deceased, etc.
[0033] "emergency worker"--any individual who is responsible for
moving an incapacitated individual from one location to an
emergency vehicle, including but not limited to EMTs, firemen,
ambulance drivers, doctors, paramedics, nurses, search and rescue,
ski patrol, etc.
[0034] Reference is initially made to FIGS. 1A-1D, which illustrate
various views of a chair cot in accordance with one embodiment of
the present invention. The embodiment of the chair cot is
designated generally at 100. The chair cot 100 is configured to
expand and collapse into two primary configurations. In the
expanded configuration (FIGS. 1A and 1D), a patient is able to be
transported in a sitting position from one location to an emergency
vehicle. In the collapsed configuration (not shown), the chair cot
100 can easily be stored in an emergency vehicle. The chair cot can
be operated by a single emergency worker allowing a second
emergency worker to perform medical functions on the patient. The
chair cot 100 generally includes two control systems 150, a back
support 110, an arm rest 105, a seat 115, a foot rest 120, and a
support and movement system 200. These components operate together
to provide the functionality of the chair cot 100.
[0035] The control systems 150 enable an emergency worker to
operate the chair cot 100. This operation includes pushing,
guiding, steering, and directing the chair cot 100 in the desired
directions. In addition, the control system 150 is configured to
control the movement of the chair cot 100 through the use of a
braking system. This allows an operator to slow the descent of the
chair cot 100 down a decline. An identical independent control
system 150 is located on either side of the chair cot 100, for
explanation purposes only one system will be described. The control
system 150 further includes a handle 156, a brake attachment 158, a
brake lever 162, a pivotable arm 152, a pivot bolt 160, and a pivot
bracket 154. The handle 156, brake attachment 158, and brake lever
162 are all disposed on the pivotable arm 152 to allow for
customization of the control system 150. For example, in some
situations an emergency worker may wish to push the chair cot 100
up an incline and a lowered pivot arm 152 is preferable. Likewise,
when transferring the chair cot 100 over a level surface, a
substantially level pivot arm 152 may be optimal. The pivoting also
allows the chair cot 100 to collapse. The pivot arm 152 also
includes a pivot bolt 160 that extends through a hole in the pivot
bracket 154. This allows the pivot arm 152 to pivot with respect to
the pivot bracket 154. A locking pin and hole mechanism is also
disposed on the pivot arm 152 and pivot bracket 154 to facilitate
locking the pivot arm 152 in a particular configuration. The brake
lever 162 is part of a braking system that is configured to slow
and stop the rotational movement of the support and movement system
200.
[0036] The back support 110 is pivotally coupled to the control
system 150, the arm rest 105, and the seat 115. This pivotable
coupling allows for the chair cot 100 to be collapsed. Various
pivoting systems may be used and remain consistent with the present
invention. The back support 110 is configured to be positioned in a
manner to provide support for a patient's back during
transportation in a seated position. Likewise, the arm rest 105 is
configured to provide support for a patient's arms during
transportation and the seat is configured to provide lower support
for a patient during transportation. A foot rest 120 is also
pivotally coupled to the seat 115 to provide additional patient
transportation configurations. The back support 110, arm rest 105,
and seat 115 can be adjusted to various angles with respect to one
another to create various seating configurations. FIG. 1C
illustrates a pivoting mechanism between the back support 110 and
the arm rest 105. The arm rest 105 is coupled to a pivot arm 107
that includes a pivot bolt 109. The pivot arm 107 is configured to
rotate or pivot with respect to the pivot bolt 109. The pivot bolt
109 is also coupled to the pivot bracket 112 which is coupled to
the back support 110. A locking pin and hole system is also
utilized to releasably lock the pivot arm 107 in a particular
configuration with respect to the pivot bracket 112. The pivot
bracket 112 is coupled to the back support 110 as shown.
[0037] The support and movement system 200 includes a support
system that provides support for the chair cot 100 and a movement
system that allows the chair cot 100 to utilize rotational movement
during transportation. The illustrated support and movement system
200 includes a V-shaped support bracket 205 coupled to a dual track
210. The dual track 210 acts like an elongated wheel to allow the
chair cot 100 to translate utilizing rotational movement and
support. The dual track 210 incorporates a ribbed track to
facilitate ascending and descending stepped and irregular surfaces.
The dual track 210 is configured to pivot or rotate with respect to
the V-shaped bracket 205 to facilitate translation over irregular
surfaces.
[0038] Reference is next made to FIGS. 2A-2D, which illustrate
various views of an alternative embodiment of a chair cot in
accordance with the present invention. The embodiment of the chair
cot is designated generally at 300. The chair cot 300 is configured
to expand and collapse into two primary configurations. In the
expanded configuration (FIGS. 2A, 2C, and 2D), a patient is able to
be transported in a sitting position from one location to an
emergency vehicle. In the collapsed configuration (FIG. 2B), the
chair cot 300 can easily be stored in an emergency vehicle. The
chair cot can be operated by a single emergency worker allowing a
second emergency worker to perform medical functions on the
patient. The chair cot 300 generally includes two control systems
350, a back support 310, a seat 315, a foot rest 320, and a support
and movement system 400. These components operate together to
provide the functionality of the chair cot 400.
[0039] The control systems 350 enable an emergency worker to
operate the chair cot 300. This operation includes pushing,
guiding, steering, and directing the chair cot 300 in the desired
directions. An identical independent control system 350 is located
on either side of the chair cot 300, for explanation purposes only
one system will be described. The control system 350 further
includes a handle 356 and a pivotable arm 352. The handle 156 is
disposed on the pivotable arm 352 to allow for customization of the
control system 350. For example, in some situations an emergency
worker may wish to push the chair cot 300 up an incline and a
lowered pivot arm 352 is preferable. Likewise, when transferring
the chair cot 300 over a level surface, a substantially level pivot
arm 352 may be optimal. The pivoting functionality also allows for
the chair cot 300 to collapse as shown in FIG. 2B. The pivot arm
352 includes a pivot bolt that extends through a hole in the back
support 310. This allows the pivot arm 352 to pivot with respect to
the back support 310. A locking pin and hole mechanism is also
disposed on the pivot arm 352 and back support 310 to facilitate
locking the pivot arm 352 in a particular configuration.
[0040] The back support 310 is pivotally coupled to the control
system 350 and the seat 315. This pivotable coupling allows for the
chair cot 300 to be collapsed. Various pivoting systems may be used
and remain consistent with the present invention. The back support
310 is configured to be positioned in a manner to provide support
for a patient's back during transportation in a seated position.
Likewise, the seat is configured to provide lower support for a
patient during transportation. A foot rest 320 is also pivotally
coupled to the seat 315 to provide additional transportation
configurations and foot support. In the illustrated embodiment, the
foot rest 320 further includes a pivot bar 319 and a second handle
322. The pivot bar 319 provides additional support and stability to
the foot rest 320. The second handle 322 is useful in transporting
the chair cot 300 in the collapsed configuration, as shown in FIG.
2B. The back support 310, seat 315, and foot rest 320 can be
adjusted to various angles with respect to one another to create
various seating configurations. The seat 315 further includes a
pivot arm 317 that utilizes a pivot bolt, pivot bracket, lock and
pin type pivoting mechanism as described above.
[0041] The support and movement system 400 includes a support
system that provides support for the chair cot 300 and a movement
system that allows the chair cot 300 to utilize rotational movement
during transportation. The illustrated support and movement system
400 includes a two support members 330, a support bar 325, a two
track attachments 405, and two tracks 410. The support members 330
extend down from the back support 310 and are coupled to the track
attachments 405. The support bar 325 extends between the support
members 330 to provide lateral support and stability. The track
attachments 405 are coupled to the tracks 410 in a manner to
facilitate the rotational freedom of the tracks 410. The tracks 410
act like elongated wheels to allow the chair cot 300 to translate
utilizing rotational movement and support. The tracks 410 each
incorporate a ribbed track to facilitate ascending and descending
stepped and irregular surfaces. The tracks 410 are configured to
pivot or rotate with respect to the support members 330 to
facilitate translation over irregular surfaces.
[0042] Reference is next made to FIGS. 3A-3C, which illustrate
various views of an alternative embodiment of a chair cot in
accordance with the present invention. The embodiment of the chair
cot is designated generally at 500. The chair cot 500 is configured
to expand and collapse into two primary configurations. In the
expanded configuration (FIGS. 3A and 3B), a patient is able to be
transported in a sitting position from one location to an emergency
vehicle. In the collapsed configuration (FIG. 3C), the chair cot
500 can easily be stored in an emergency vehicle. The chair cot 500
can be operated by a single emergency worker allowing a second
emergency worker to perform medical functions on the patient. The
chair cot 500 generally includes two control systems 550, a back
support 510, a seat 515, a foot rest 520, and a support and
movement system 600. These components operate together to provide
the functionality of the chair cot 500.
[0043] The control systems 550 enable an emergency worker to
operate the chair cot 500. This operation includes pushing,
guiding, steering, and directing the chair cot 500 in the desired
directions. An identical independent control system 550 is located
on either side of the chair cot 500, for explanation purposes only
one system will be described. The control system 550 further
includes a handle 556 and a pivotable arm 552. The handle 556 is
disposed on the pivotable arm 552 to allow for customization of the
control system 550. For example, in some situations an emergency
worker may wish to push the chair cot 500 up an incline and a
lowered pivot arm 552 is preferable. Likewise, when transferring
the chair cot 500 over a level surface, a substantially level pivot
arm 552 may be optimal. The pivoting functionality also allows for
the chair cot 500 to collapse as shown in FIG. 3C. The pivot arm
552 includes a pivot bolt that extends through a hole in the back
support 510. This allows the pivot arm 552 to pivot with respect to
the back support 510. A locking pin and hole mechanism is also
disposed on the pivot arm 552 and back support 510 to facilitate
locking the pivot arm 552 in a particular configuration.
[0044] The back support 510 is pivotally coupled to the control
system 550 and the seat 515. This pivotable coupling allows for the
chair cot 500 to be collapsed. Various pivoting systems may be used
and remain consistent with the present invention. The back support
510 is configured to be positioned in a manner to provide support
for a patient's back during transportation in a seated position.
Likewise, the seat is configured to provide lower support for a
patient during transportation. A foot rest 520 is also pivotally
coupled to the seat 515 to provide additional transportation
configurations and foot support. In the illustrated embodiment, the
foot rest 520 further includes a pivot bar 519 and a second handle
522. The pivot bar 519 provides additional support and stability to
the foot rest 520. The second handle 522 is useful in transporting
the chair cot 500 in the collapsed configuration, as shown in FIG.
3C. The back support 510, seat 515, and foot rest 520 can be
adjusted to various angles with respect to one another to create
various seating configurations. The seat 515 further includes a
pivot arm 517 that utilizes a pivot bolt, pivot bracket, lock and
pin type pivoting mechanism as described above.
[0045] The support and movement system 600 includes a support
system that provides support for the chair cot 500 and a movement
system that allows the chair cot 500 to utilize rotational movement
during transportation. The illustrated support and movement system
600 includes a two support members 530, a support bar 525, a two
track attachments 605, and two tracks 610. The support members 530
extend down from the back support 510 and are coupled to the track
attachments 605. The support bar 525 extends between the support
members 530 to provide lateral support and stability. The track
attachments 605 are coupled to the tracks 610 in a manner to
facilitate the rotational freedom of the tracks 610. The tracks 610
act like elongated wheels to allow the chair cot 500 to translate
utilizing rotational movement and support. The tracks 610 each
incorporate a ribbed track to facilitate ascending and descending
stepped and irregular surfaces. The tracks 610 are configured to
pivot or rotate with respect to the support members 530 to
facilitate translation over irregular surfaces.
[0046] The movement systems of each embodiment may further include
a motor to rotate the tracks without external force. The motor may
be an electric motor coupled to some form of rechargeable and/or
replaceable power source, or it may be an electric motor coupled to
some form of AC power, such as being plugged in to a wall outlet.
The control systems of each embodiment may further include various
motor controls to facilitate movement. The movement system must
still conform to the dimensions of the chair cot embodiments such
that it can be properly collapsed for transportation. When the
movement systems include a motor, the control system may include a
forward and reverse mechanism that allows the movement system to
move forward and reverse respectively. Furthermore, the movement
system may be designed to lock in the event that power is lost.
Additionally, in some embodiments where the movement system
includes a motor, a motorized portion of the movement system may be
disengaged thereby allowing for descent and/or ascent of an
inclined/declined surface utilizing non-motorized rotational
movement.
[0047] In operation, a chair cot in accordance with the present
invention may be transported in a collapsed configuration to a
patient in need of emergency services. The chair cot may then be
expanded into the expanded configuration by locking various
pivoting members into place. Adjustments to the pivotable angles
may be made depending on the size and medical condition of the
patient. The patient is then positioned in a seated position on the
chair cot. The chair cot then utilizes rotational movement to
transfer the patient to an emergency vehicle. The chair cot is then
collapsed for storage within the emergency vehicle.
[0048] FIGS. 4-7 show perspective views of an alternate embodiment
of a chair cot in accordance with the present invention. This
embodiment of the chair cot is designated generally at 700. The
illustrated embodiment of the chair cot 700 is capable of a large
number of positions in between a fully expanded configuration and a
fully-collapsed configuration. The fully-collapsed configuration is
shown in FIG. 4. As illustrated in FIG. 4, the chair cot 700
generally includes one or more control systems (not shown), a back
support 702, a seat 704, a foot rest 706, and a support and
movement system 708. These components operate together to provide
functionality to the chair cot 700. In the fully-collapsed
configuration shown in FIG. 4, the chair cot 700 can easily be
stored in an emergency vehicle. In any expanded configuration, a
patient is able to be transported in a comfortable position from
one location to an emergency vehicle. The chair cot 700 may easily
be operated by a single emergency worker.
[0049] The control system(s) (not shown) enable an emergency worker
to operate the chair cot 700. This may include pushing, guiding,
steering, and directing the chair cot 700 in the desired directions
on relatively flat terrain. In addition, the control system(s) may
be configured to allow the emergency worker to control the movement
of the chair cot 700 through the use of a braking system and
through a powered track system. The control system(s) may be
provided on a handle 710 of the chair cot 700 and/or may be
provided on the back support 702, on the seat 704, on the support
and movement system 708, and/or may be provided as a separate
control unit.
[0050] The back support 702 may be pivotally coupled to the support
and movement system 708 at a pivot joint 712 connected to the
support and movement system 708. The pivot joint 712 may allow the
back support 702 to pivot through any position between the
fully-collapsed position and the fully-expanded position, and may
allow the pack support 702 to be positioned independently of the
seat 704 and foot rest 706. As may be seen more clearly in FIG. 6,
the back support 702 includes a back frame 714 pivotally coupled to
the pivot joint 712 to which the handle 710 is coupled. In some
embodiments, the back frame 714 and handle 710 may be provided with
an adjustable connection, such as a telescoping and/or a pivoting
connection to allow adjustment of the handle 710 relative to the
back frame 714.
[0051] As may also be appreciated more fully by reference to FIG.
6, the back support 702 may also include a cross brace 716 passing
through the back frame 714 at a location distal the connection of
the back frame 714 to the pivot joint 712. A bracket 718 may be
attached to the cross brace, and a pneumatic or hydraulic cylinder
720 may be attached to the bracket 718 and to the support and
movement system 708. The pneumatic or hydraulic cylinder 720 may be
controlled by the control system(s) discussed above, or it may be
controlled separately, such as by a control bar 722 attached to the
bracket 718 and the back frame 714 so as to be easily reached by an
emergency worker transporting a patient. This configuration allows
the back support 702 to be positioned in any position between the
fully-collapsed configuration and the fully-expanded configuration
according to the transport needs and comfort of the patient being
transported, as well as the storage needs of the chair cot 700 and
the emergency worker and/or emergency vehicle.
[0052] FIG. 7 shows a detailed perspective view of one embodiment
of the connection between the bracket 718, the pneumatic or
hydraulic cylinder 720, and the control bar 722, to illustrate one
way in which the control bar 722 may function to control the
pneumatic or hydraulic cylinder 720 to adjust the position of the
back support 702. In the illustrated embodiment, the control bar
722 may actuate the pneumatic or hydraulic cylinder 720 by a
lateral movement (a movement in either direction along the long
axis of the control bar 722). In the illustrated embodiment, a bolt
724 connects the bracket 718 to the cross brace (not shown in FIG.
7). The bracket 718 is connected to the control bar 722 with rocker
arms 726 that translate the lateral movement of the control bar 722
into a pressing of a release mechanism 728 on the pneumatic or
hydraulic cylinder 720. When the release mechanism 728 is pressed,
the pneumatic or hydraulic cylinder 720 is allowed to move so as to
position the back support 702 into a desired position. Then, when
the control bar 722 is returned to its normal position and the
release mechanism 728 is no longer pressed, the pneumatic or
hydraulic cylinder 720 locks in place again to hold the back
support 702 in the desired position.
[0053] As may be seen by reference to FIGS. 4 and 5, the seat 704
may also be provided with a pivot joint connection to the support
and movement system 708 as well as a pneumatic or hydraulic
cylinder 730, a bracket 732 and a control bar 734 similar to the
hydraulic cylinder 720 and control bar 722 provided for the back
support 702. In this manner, the seat 704 may also be positioned at
any position between a fully-collapsed configuration and a
fully-expanded configuration. In some embodiments, for simplicity,
the seat 704 and the back support 702 may utilize the same pivot
joint location, namely the location of pivot joint 712.
[0054] The described combination of adjustability provides for
improved patient support and comfort for a wide variety of patient
needs, as well as transportation situations, such as various
inclined surfaces, as will be discussed further below. Other
embodiments of the brackets 718 and 732 and control bars 722 and
734, including embodiments that allow release of the pneumatic or
hydraulic cylinders 720 and 730 with up and down or with
any-directional movement of the control bars 722 and 734 are
embraced by the various embodiments of the invention. Additionally,
embodiments in which the pneumatic or hydraulic cylinders 720 and
730 are controlled by a powered system using the control system(s)
(not shown) are also embraced by the invention. Therefore, the
discussed embodiments are meant to be illustrative and not
limiting.
[0055] In some embodiments, the seat 704 may include a seat frame
736, as may be seen in FIG. 5. The foot rest 706 may be connected
to the seat frame 736 by a linkage 738. In some embodiments, the
linkage 738 may be a passive linkage so that the foot rest 706
naturally rests in one of two configurations, a fully-folded
configuration seen in FIG. 4, and a fully-expanded configuration
seen in FIG. 5. In instances where the seat 704 has not been moved
to an expanded-enough position to allow the foot rest 706 to assume
the fully-expanded configuration seen in FIG. 5, the foot rest 706
may naturally rest in as expanded a configuration as possible, with
the foot rest 706 resting on a portion of the support and movement
system 708. As illustrated in FIGS. 4-6, the foot rest 706 may have
a roughly U-shaped configuration, and the patient's feet may
naturally rest at the bottom of the U-shaped configuration during
transport. During storage of the chair cot 700, the foot rest 706
readily folds up in a compact fashion as shown in FIG. 4.
[0056] In some embodiments, depending on the size of the patient
and/or the angle of adjustment of the seat 704 and back support
702, it may be advantageous to provide a separate place to support
the feet of the patient being transported other than the foot rest
706. Therefore, in some embodiments, the support and movement
system 708 may be provided with additional foot support structures
(not shown) in locations convenient for supporting the patient'
feet. In some embodiments, the additional foot support structures
may be detachable structures and, in other embodiments, the
additional foot support structures may be fixedly attached to the
support and movement system 708. One of skill in the art may
readily appreciate the possible locations of the additional foot
support structures, and will also recognize that the additional
foot support structures should adequately shield patient' feet from
any moving parts during transport.
[0057] In the configuration shown in FIG. 4, the chair cot 700 may
be readily adapted for use as a spinal immobilization and transport
device. As may be appreciated by reference to FIG. 4, when the
chair cot 700 is fully folded, the foot rest 706 and the back frame
714 of the back support 702 may provide a coplanar surface that may
be utilized to provide a spinal immobilization support surface. In
some embodiments, the handle 710 may be used and extended to
further extend the coplanar surface supporting the immobilization
surface. In this configuration, a separate, unitary rigid spinal
immobilization surface (not shown) may be placed over and secured
to the chair cot 700, and a patient may be immobilized for
motorized or non-motorized transportation over horizontal and
inclined/declined surfaces using straps (not shown) secured to the
back frame 714, to the seat frame 736, the foot rest 706, and/or
the support and movement system 708. In this way, the chair cot 700
may be used for at least three purposes, namely as a patient
transport device with the patient transported in a sitting
position, as a spinal immobilization and transport device with the
patient transported in a reclined position, and as a inclined
surface/stair ascending/descending device.
[0058] As discussed above, the back support 702 and the seat 704
may include the back frame 714 and the seat frame 736. Each of the
back frame 714, the seat frame 736, the handle 710 and the foot
rest 706 may be manufactured from extruded aluminum to keep the
weight of the chair cot 700 low while providing a strong chair cot
700 capable of supporting a wide range of patient weights. In other
embodiments, some or all of these components may be manufactured
from other materials such as tubular steel. Any combination of
these materials and other materials may also be used. Any material
that provides for the features discussed herein is embraced by the
various embodiments of the invention.
[0059] FIGS. 4-6 show an additional feature of the chair cot 700
that may be highly beneficial to emergency workers. Regulations
affecting emergency workers generally provide that the emergency
workers must provide patients to be transported with a clean
surface for transport. This often requires a great deal of work for
emergency workers after transporting a patient, as the emergency
workers must wipe down and sanitize any surfaces with which the
transported patient came in contact. This may be particularly
onerous in cases where bodily fluids have come in contact with
patient transport surfaces. It has historically been difficult for
emergency transport companies to easily bill for the time the
emergency workers spend cleaning patient transport surfaces and
equipment. These problems are addressed by the embodiment of the
invention shown in FIGS. 4-6.
[0060] In the illustrated embodiment, the back support 702 and seat
704 are provided with a disposable back surface 740 and a
disposable seat surface 742, respectively. In other embodiments,
fixed, reusable surfaces may also be used. The disposable back
surface 740 and the disposable seat surface 742 may be disposed
after each use, and may therefore be charged to transported
patients and/or their insurance companies as consumables/billables.
As the disposable back surface 740 and disposable seat surface 742
are disposable, they may be made from any relatively inexpensive
and sturdy material, such as plastics, with representative examples
being corrugated or non-corrugated polypropylene, acrylonitrile
butadiene styrene (ABS), and various kinds of polyethylene: ultra
high molecular weight (UHMW) polyethylene, high density
polyethylene (HDPE), and low density polyethylene (LDPE). When they
are made from a material such as polypropylene, they may readily be
customized for the particular emergency transport company with
words and/or logos, such as by screen printing.
[0061] The disposable back surface 740 and the disposable seat
surface 742 may be releasably but securely engaged to the back
frame 714 and seat frame 736 during use. This may be provided in
any number of manners or means for securing the disposable back
surface 740 and the disposable seat surface 742 to the chair cot
700, such as by snaps, straps, hook-and-loop fasteners, etc., but
in the embodiment illustrated in FIGS. 4-6, the engagement is
provided by indexing pins 744, indexing receptacles 746, and
magnets 747. In the illustrated embodiment, the indexing pins 744
are fixedly attached to or through the disposable back surface 740
and the disposable seat surface 742 and extend into the
corresponding indexing receptacles 746 in the back frame 714 and
seat frame 736. This prevents unwanted lateral movement of the
disposable back surface 740 and the disposable seat surface 742
during use.
[0062] To secure the disposable back surface 740 and the disposable
seat surface 742 to the back frame 714 and the seat frame 736 so
that the disposable back surface 740 and the disposable seat
surface 742 do not lift off and disengage the indexing pins 744
from the indexing receptacles 746, the disposable back surface 740
and the disposable seat surface 742 may be provided with magnets
(not shown). The magnets may be either provided in the disposable
back surface 740 and the disposable seat surface 742 and directly
attracted to the back frame 714 and the seat frame 736 (when the
back frame 714 and the seat frame 736 are made of magnetic
materials) or may be attracted to corresponding magnets 747
attached to or manufactured into the back frame 714 and the seat
frame 736. Alternatively, inserts made from a
magnetically-attractable material such as magnets (not shown),
iron, or steel may be manufactured into the disposable back surface
740 and the disposable seat surface 742. In some embodiments, the
inserts may be manufactured into the disposable back surface 740
and the disposable seat surface 742 so as to not be externally
visible and to reduce the number of external surfaces needed to be
sterilized.
[0063] In the illustrated embodiment, the indexing pins 744 are
located on the disposable seat surface 742 and the disposable back
surface 740 and the indexing receptacles 746 are located on the
back frame 714 and the seat frame 736. However, in other
embodiments, the indexing pins 744 may be located on the back frame
714 and the seat frame 736, and the indexing receptacles 746 may be
located on the disposable seat surface 742 and the disposable back
surface 740. This may reduce manufacturing costs, as the indexing
receptacles may be manufactured into the disposable back surface
740 and the disposable seat surface 742 as simple holes, with or
without reinforcements such as grommets.
[0064] Also shown in the illustrated embodiment, the magnets 747
are located proximal the indexing pins 744 and the indexing
receptacles 746 so as to better secure the disposable back surface
740 and the disposable seat surface 742 to the back frame 714 and
to the seat frame 736 against any flexing that might occur during
use of the chair cot 700. Although not specifically shown in the
illustrated embodiment, the disposable back surface 740 and the
disposable seat surface 742 may be manufactured so as to be
sterilized and reusable. In embodiments where a corrugated material
is used, the disposable back surface 740 and the disposable seat
surface 742 may be made reusable by providing an edge trim (not
shown) that prevents bodily fluids and other liquids or pathogens
from entering the fluting of the corrugated material where it is
more difficult to clean. Therefore, in such embodiments, the
disposable back surface 740 and the disposable seat surface 742 may
be reused a limited or unlimited number of times until it is
determined that cleaning is no longer sufficiently effective or
desired.
[0065] As may be appreciated from the above discussion, when the
chair cot 700 is used as a spinal immobilization and transport
device, the indexing pins 744, the indexing receptacles 746, and
the magnets 747 may be used to secure the removable spinal
immobilization surface discussed above. As may be further
appreciated, the spinal immobilization surface may therefore be a
disposable spinal immobilization surface. In all such embodiments,
the disposable back surface 740 may be removed before the spinal
immobilization surface, whether disposable or not, is attached.
Also, in such embodiments, the foot rest 706 may also be provided
with indexing pins 744 or indexing receptacles 746 and magnets 747
to better secure the spinal immobilization surface to the chair cot
700. As may be appreciated, the disposable seat surface 742 may be
removed or may remain in place, as it does not interfere with
placement of the spinal immobilization surface. As may also be
appreciated given the purpose of the spinal immobilization surface,
the spinal immobilization surface, whether disposable or not, may
be manufactured of a stronger and stiffer material (i.e. thicker
material) in some embodiments to ensure full spinal
immobilization.
[0066] Using the disposable back surface 740 and the disposable
seat surface 742 (and the disposable spinal immobilization surface)
of the present invention, an emergency worker need not wipe down
and sanitize the disposable back surface 740 and the disposable
seat surface 742 of the chair cot 700 after each patient, but need
merely remove and discard the disposable back surface 740 and the
disposable seat surface 742. The emergency transportation company
then can bill the disposable back surface 740 and the disposable
seat surface 742 as a billable/consumable as part of its billing
services. This provides a convenience and service to the emergency
worker and the emergency transportation company. One of skill in
the art will readily recognize the variety of uses to which such
disposable surfaces can be put.
[0067] Disposable surfaces of the type described are not limited to
use with chair cots such as described herein, but may be
advantageously used for other medical uses and medical equipment,
such as for gurneys, cots, or any other use where a disposable
surface that can be replaced and billed as a consumable is
desirable. For all such uses, it may be desirable that the
disposable surface include at least one liquid impermeable layer to
prevent the transmission of bodily fluids to underlying equipment.
It may also be desirable to provide an absorbent layer to absorb
any bodily or other fluids landing on the disposable surface. As
above, the disposable surface may include a means for securing the
disposable surface to a location or to underlying equipment, and
the means for securing may include any means known in the art for
reversibly securing the disposable surface, such as hook-and-loop
fasteners, straps, snaps, screws, indexing pins and indexing pin
receptacles, magnets, etc.
[0068] In other embodiments, it may not be desirable to use
disposable surfaces such as those described above. In those
embodiments, the various support surfaces may be permanent or
semi-permanent surfaces, and may be manufactured of any suitable
long-lasting material, such as plastic. Examples of such materials
include ABS plastic, HDPE, LDPE, UHMWPE, and polypropylene.
[0069] Turning now to the support and movement system 708 of the
chair cot 700, the support and movement system 708 of the
illustrated embodiment is provided with features that facilitate
movement of the chair cot 700 over level flat surfaces as well as
over inclined surfaces, including stairs and other stepped and
irregular surfaces, regardless of whether a patient is seated in
the chair cot 700 and regardless of the size of the person seated
in the chair cot 700. These features will be addressed in more
detail. In the illustrated embodiment, the support and movement
system 708 includes dual tracks 748, a motor drive unit 750,
casters 752, and retractable rear wheels 754. As discussed above,
in some embodiments, additional support structures (not shown) may
be provided in addition to the foot rest 706. In some embodiments,
the casters 752 provide a convenient location for mounting the
additional support structures to the support and movement system,
as may be appreciated by reference to FIGS. 4 and 5. Although not
specifically illustrated in detail in FIGS. 4-6, the dual tracks
748 may be ribbed tracks, as discussed further with reference to
FIGS. 8A and 8B.
[0070] When the chair cot 700 is deployed and used on a relatively
flat and level surface, the retractable rear wheels 754 may be
deployed as seen in FIGS. 5 and 6. When the retractable rear wheels
754 are deployed, the rear end of the chair cot 700 is raised
somewhat, lifting the dual tracks 748 off of the surface so that
the casters 752 engage the surface. Thus, in such a configuration,
the chair cot 700 may be readily pushed or pulled in a desired
direction by an emergency worker, and the emergency worker can
readily steer the chair cot 700 using the rotation of the casters
752. Although not specifically illustrated in the Figures, in one
embodiment, the chair cot 700 may also be provided where the
casters 752 are replaced with fixed directional wheels and the
retractable rear wheels 754 may be replaced with retractable rear
casters. In such a manner, the chair cot may still be readily
steered in use.
[0071] The dual tracks 748 may be used on flat surfaces also,
however. The use of the dual tracks 748 on flat surfaces may be
desirable if the surface is uneven, or if the slope of the surface
varies from flat to inclined. To use the dual tracks 748 instead of
the retractable rear wheels 754 and casters 752, the retractable
rear wheels 754 are retracted to a stowed position. The dual tracks
748 may be driven by the motor drive unit 750, which may include a
high-efficiency motor and a power unit such as a battery. The dual
tracks 748 and the motor drive unit 750 may be controlled using the
control system(s) (not shown) previously discussed above, and may
provide relatively fast translation across varied surfaces.
[0072] The combination of the dual tracks 748, the casters 752, and
the retractable rear wheels 754 provides for improved transport of
patients up and down inclined and varied surfaces such as stairs,
as well as improved transitioning from movement on a horizontal
flat surface to a stairway and vice-versa, as will now be
described. When the chair cot 700 is being used with the dual
tracks 748 on a flat surface, transitioning to an inclined surface,
such as a stairway, is straightforward: the chair cot 700 simply
continues onto the inclined surface or stairway. If necessary to
engage the first step or two when ascending a stairway, the
operator might lift the rear end of the chair cot 700 slightly to
allow the dual tracks 748 to engage the first step or two more
readily. This engagement may be assisted by teeth or ribbing
provided on the dual tracks 748 as discussed with reference to
FIGS. 8A-8E. Additionally, as the chair cot 700 moves to or from an
inclined surface, an operator may adjust the angle of the back
support 702 and/or seat 704 as discussed previously for the comfort
and safety of the patient.
[0073] When the chair cot 700 has been or is desired to be used
with the casters 752 and the retractable rear wheels 754 on
more-horizontal surfaces, it is advantageous to transition to using
the dual tracks 748 for inclined surfaces such as stairways. This
may be done by selectively stowing and deploying the retractable
rear wheels 754 at the beginning and ending of the stairway,
respectively, as follows. In all instances where a stairway is
being ascended or descended, it may be desirable to lock the
position of the casters 752 and to lock the rear wheels 754 in a
stowed position to reduce the likelihood of accidents. Therefore,
it is anticipated that the embodiments of the chair cot 700 are
provided with means for locking the position of the casters 752 and
with means for locking the rear wheels 754 in a stowed position
during ascent and descent.
[0074] When a stairway is to be descended, the operator simply
pushes the chair cot 700 to the edge of the stairway and then
pushes the casters 752 of the chair cot 700 off the edge of the
first step so that the dual tracks 748 contact the edge of the
first step. At this point, the retractable rear wheels 754 still
contact the flat surface at the top of the stairs. The dual tracks
748 may then be activated so as to begin descending the stairs. As
the descent begins, the operator may either slightly lift the rear
end of the chair cot 700 or may allow the weight of the chair cot
700 to begin lifting the end of the chair cot 700 (as the center of
gravity of the chair cot 700 passes over the lip of the first
stair), and may then use a foot lever (not shown) or other release
mechanism to retract/stow the retractable rear wheels 754 out of
the way of the stairs. In the illustrated embodiment, the
retractable rear wheels 754 retract/stow by rotating forward under
the chair cot 700. If the operator discovers that the chair cot 700
has descended too far to allow retraction/stowing of the
retractable rear wheels 754, the operator merely reverses the
direction of travel of the chair cot 700 a slight amount until the
retractable rear wheels 754 may be stowed.
[0075] At the bottom of the stairway, the casters 752 naturally and
automatically contact the horizontal surface first. The operator
can continue using the dual tracks 748 all the way down the
stairway (thus transitioning to use of the dual tracks 748 on the
horizontal surface and discontinuing use of the casters 752), or
the operator can lift the rear end of the chair cot 700 slightly
(and may optionally activate a rear wheel release mechanism such as
a foot petal or button) so as to allow the retractable rear wheels
754 to redeploy. In some embodiments, the retractable rear wheels
754 may be spring-loaded or otherwise biased so as to be
automatically redeployed when the operator lifts the rear end of
the chair cot 700. In such embodiments, the retractable rear wheels
754 do not deploy while descending the staircase as there is
insufficient room on each step for the retractable rear wheels 754
to deploy. Instead, the retractable rear wheels 754 may move
slightly from their fully-stowed position but on encountering the
next step will merely roll over the step and will return to their
fully-stowed position as the retractable rear wheels 754 pass over
the corner of each step. In such embodiments, a lock may be
optionally provided to lock the retractable rear wheels 754 in
their fully-stowed position when desirable, such as where the pitch
and spacing of the stairs would otherwise allow full deployment of
the retractable rear wheels 754.
[0076] In other embodiments, a release or control such as a foot
lever or button (not shown) may be used to redeploy the retractable
rear wheels 754 at the bottom of the stairway. Thus, regardless of
the mechanism for stowing and redeploying the retractable rear
wheels 754, the illustrated embodiment of the chair cot 700 allows
for easy transition between controlled, powered movement down a
stairway and controlled operator pushing/pulling of the chair cot
on horizontal surfaces. Similar transitioning may be accomplished
between travel on horizontal surfaces and controlled, powered
movement up a stairway.
[0077] This may be accomplished by backing the chair cot up to the
bottom of the stairs. At the bottom of the stairs, as may be
appreciated by reference to FIG. 5, the retractable rear wheels 754
will contact the riser or tread of the first step of the stairway.
At this point, the operator may continue pulling on the chair cot
700 (and may slightly lift the rear end of the chair cot 700),
causing the retractable rear wheels 754 to be forced by the first
step into their stowed position, with the dual tracks 748 resting
on the first or second step of the stairway. Alternatively, a
release or control such as a foot lever (not shown may be used to
stow the retractable rear wheels 754. In another alternative
embodiment, the retractable rear wheels may be provided with an
automatic release that strikes the riser or tread of the first step
and automatically releases/stows the retractable rear wheels 754 to
allow the dual tracks 748 to engage the stairway. Regardless of the
mechanism of stowing the retractable rear wheels 754, once the dual
tracks 748 engage the stairway, the motor drive unit 750 may be
engaged to power the chair cot 700 up the stairs to the top of the
stairs.
[0078] At the top of the stairs, the retractable rear wheels 754
may be redeployed manually or automatically, as discussed above for
redeploying the retractable rear wheels 754 at the bottom of a
stairway when descending the stairway. The dual tracks 748 may then
continue to be used to finish climbing the stairs until the casters
752 are just over the lip of the stair, and a slight pull on the
handle 710 of the chair cot 700 will complete the transition back
to non-powered rolling on the casters 752 and retractable rear
wheels 754 on the horizontal surface. Thus, one of skill in the art
will readily appreciate that the chair cot 700 provides for simple
and easy transitioning to climbing a stairway up or down from a
horizontal surface and vice-versa. With minimal practice, an
operator can make these transitions seamlessly and quickly,
allowing for improved patient comfort as the patient is transported
from a multi-story building in an emergency situation.
[0079] It is anticipated that the described embodiments of the
support and movement system 708 may be readily adopted to
situations besides the emergency-use chair cot 700 described with
reference to FIGS. 4-7. While it may be readily recognized that the
chair cot 700 may be used for home health and as a multi-story
evacuation device, such as for nursing homes, the movement and
support system 708 may be adapted for use in still other
situations. For example, the support and movement system 708 may be
used as a base for a wheelchair. Additionally, the described
support and movement system 708 may be used as a home and garden
transport platform. It has been found that the support and movement
system 708 can readily move a patient weighing more than 500 pounds
(227 kilograms) up or down numerous flights of stairs on a single
charge. As a home or garden transport platform, this means that a
user could easily move the same weight of materials in similar
fashion with very little effort on the part of a user. This may be
practical and advantageous, for example, for deliveries,
construction materials, and/or persons moving to/from an apartment
in a multistory building. Thus, there are many potential uses for
the described support and movement system 708.
[0080] As discussed above, the dual tracks 748 may be ribbed to
improve security of the dual tracks 748 when ascending or
descending irregular surfaces such as stairs. One embodiment of the
dual tracks 748 is illustrated in more detail in FIGS. 8A and 8B.
FIGS. 8A-8D illustrate a section of a continuous track 756 used
with each of the dual tracks 748. As may be seen by reference to
FIG. 5, the continuous track 756 forms a loop around a drive gear
758 and pulley 760. The drive gear 758 is connected to the motor
drive unit 750 and provides power to the continuous track 756.
Along the remainder of its length, the continuous track 756 may
ride along a low-friction slider 762 that may be manufactured of a
plastic such as UHMW polyethylene, HDPE, or LDPE. Use of the
low-friction slider 762 has been found to improve efficiency of the
support and movement system 708, allowing the support and movement
system 708 to lift approximately 60% more weight up inclined
surfaces such as stairways.
[0081] Returning now to FIG. 8A, the Figure shows a plan view of a
small section of the continuous track 756, showing one embodiment
of the repeating profile of the continuous track 756. The
illustrated section shown is from the bottom, surface-contacting
portion of the continuous track 756, so the surface of the
continuous track 756 that contacts the stairway or ground is
downward in FIG. 8A. The continuous track 756 shown has three
layers: a tread layer 764, a fiber layer 766, and a drive layer
768. As shown in FIG. 8A, the tread layer 764 and the drive layer
768 have teeth or ribs 770 and teeth or ribs 772, respectively. The
teeth or ribs 770 of the tread layer 764 engage stairs or other
irregular surfaces being ascended or descended for security. The
teeth or ribs 770 may have a flattened top 774 to reduce wear by
preventing a sharp-peaked top from being irregularly torn during
use. The teeth or ribs 772 of the drive layer 768 engage the drive
gear 758 to transfer power from the motor drive unit 750 to the
continuous track 756. The teeth or ribs 772 may also engage a
channel or guide in the drive gear 758, pulley 760, and/or slider
762 to keep the continuous track 756 properly aligned during use,
as may be appreciated by reference to FIGS. 8B and 8C, that show an
embodiment of a channel 776 in the continuous track 756.
[0082] The tread layer 764 and the drive layer 768 may be
manufactured from materials such as neoprene, urethane, rubber, and
the like. In some embodiments, the tread layer 764 may have a
durometer of between approximately 60A and 70A and in some
embodiments a durometer of approximately 70A to provide softness
and improved wear of the continuous track 756. This hardness of the
tread layer 764 has proved to have an extremely long life during
use and has proved useful for ascending or descending a large
variety of stairway configurations. The drive layer 768 may have a
higher durometer of between 80A and 55D or between 85A to 95A, and
in some embodiments a durometer of approximately 90A to maintain
flexibility but provide tooth strength for interaction with the
drive gear 758.
[0083] The fiber layer 766 provides strength to the continuous
track 756 and prevents undue expansion or stretching of the
continuous track 756 when loaded. The fiber layer 766 may include
high-strength durable fibers such as steel fibers, polyesters,
fiberglass, or long molecular chains of poly-paraphenylene
terephthalamide produced from a condensation reaction between
monomers of 1,4-phenylene-diamine (para-phenylenediamine) and
terephthaloyl chloride, and commonly sold by E. I. du Pont de
Nemours and Company as KEVLAR.RTM.. The fiber layer 722 provides
tensile strength to the continuous track 756 so that the continuous
track 756 can withstand large tensile loads as the chair cot 700 is
used to ascend or descend stairways. By way of example, and not
limitation, the illustrated embodiment of the continuous track 756
can withstand between 100 and 2,000 inch/lbs of torque.
[0084] By way of example and not limitation, one embodiment of the
continuous track 756 will be illustrated with reference to FIG. 8E
in specific detail. It is anticipated that one or more of the
measurements discussed herein may be modified and still fall within
the scope of the present invention. In the illustrated embodiment,
the continuous track 756 may have a height of approximately
0.95-1.16 inches (24.1-29.5 mm) or between 1.05-1.06 inches
(26.7-26.9 mm), as measured from the tip (i.e. the flattened top
774) of teeth or ribs 770 to the tip of teeth or ribs 772. This
height may be varied for reasons of weight or strength of the
continuous track 756. The teeth or ribs 772 may have a
tooth-to-tooth spacing of approximately 0.28-0.35 (7.1-8.9 mm) or
0.31-0.32 inches (7.9-8.1 mm) or of approximately 0.315 inches (8
mm), and with such a spacing, the drive gear 758 and pulley 760 may
have a diameter of approximately 4 inches (100 mm). As may be
appreciated by one of skill in the art, varying the size and
spacing of the teeth or ribs 772 may permit or require varying the
size of the drive gear 758 and pulley 760 accordingly.
[0085] The teeth or ribs 770 may have a tooth-to-tooth spacing of
approximately 1.51-1.84 inches (38.4-46.7 mm) or of 1.67-1.68
inches (42.4-42.7 mm), or of approximately 1.675 inches (42.5 mm).
The height of the teeth or ribs 770 from a valley 778 to the flat
top 774 may be approximately 0.54-0.66 inches (13.7-16.8 mm) or
approximately 0.59-0.61 inches (15.0-15.5 mm) or approximately 0.6
inches (15.2 mm). These tooth-to-tooth spacings and teeth heights
have been found to function well at securely climbing and/or
descending a wide variety of stairway configurations, rises, runs,
and step spacings. The valley 778 of the teeth or ribs 770 may be
provided with a curve, and the radius of curvature of the valley
778 may be approximately 0.22-0.28 inches (5.6-7.1 mm) or
approximately 0.25 inches (6.4 mm). As indicated previously, the
teeth or ribs 770 may be provided with the flattened top 774 to
reduce wear, and the flattened top 774 may have a width of
approximately 0.17-0.21 inches (4.3-5.3 mm) or approximately .19
inches (4.8 mm).
[0086] The present invention may be embodied in other specific
forms without departing from its spirit of essential
characteristics. The described embodiments are to be considered in
all respects only as illustrative and not restrictive. The scope of
the invention is, therefore, indicated by the appended claims,
rather than by the foregoing description. All changes which come
within the meaning and range of equivalency of the claims are to be
embraced within their scope.
* * * * *