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Publication numberUS20070182220 A1
Publication typeApplication
Application numberUS 11/734,229
Publication dateAug 9, 2007
Filing dateApr 11, 2007
Priority dateFeb 22, 2005
Also published asWO2008127944A1
Publication number11734229, 734229, US 2007/0182220 A1, US 2007/182220 A1, US 20070182220 A1, US 20070182220A1, US 2007182220 A1, US 2007182220A1, US-A1-20070182220, US-A1-2007182220, US2007/0182220A1, US2007/182220A1, US20070182220 A1, US20070182220A1, US2007182220 A1, US2007182220A1
InventorsNathan Walkinshaw, Tad Clark, Mark Wenzel
Original AssigneeWalkinshaw Nathan R, Tad Clark, Mark Wenzel
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Folding Chair Cot For Use With Emergency Vehicles
US 20070182220 A1
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.
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Claims(21)
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

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

1. Field of the Invention

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.

2. Background

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.

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

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.

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

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.

FIG. 1A is a profile view of a chair cot in accordance with one embodiment of the present invention;

FIG. 1B is a detailed view of the control system illustrated in FIG. 1A;

FIG. 1C is a detailed view of the collapsing mechanism attached to the arm rest illustrated in FIG. 1A;

FIG. 1D is a front view of the chair cot illustrated in FIG. 1A;

FIG. 2A is a profile view of an alternative embodiment of an expanded chair cot in accordance with the present invention;

FIG. 2B is a profile view of the chair cot illustrated in FIG. 2A in a collapsed configuration;

FIG. 2C is a front view of the expanded chair cot illustrated in FIG. 2A;

FIG. 2D is a perspective view of the expanded chair cot illustrated in FIG. 2A;

FIG. 3A is a perspective view of an alternative embodiment of an expanded chair cot in accordance with the present invention;

FIG. 3B is a profile view of the expanded chair cot illustrated in FIG. 3A;

FIG. 3C is profile view of the chair cot illustrated in FIG. 3A in a collapsed configuration;

FIG. 4 is a perspective view of an alternate embodiment of a chair cot in a collapsed position;

FIG. 5 is a perspective view of the chair cot illustrated in FIG. 4 in an expanded position;

FIG. 6 is a perspective view of the chair cot illustrated in FIG. 4 in an expanded position;

FIG. 7 is a detailed perspective view of a hydraulic release element from the chair cot illustrated in FIG. 4; and

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

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.

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.

The following terms are defined as follows:

“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.

“gurney”—a wheelable bed device used in hospitals and other facilities to easily transport patients over flat surfaces.

“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.

“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.

“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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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®. 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.

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.

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).

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.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US7810820May 6, 2005Oct 12, 2010Arc Products LlcLightweight plastic sleds for emergency transport and hauling of loads
US8172238Jun 14, 2010May 8, 2012Arc Products LlcLightweight plastic sleds for emergency transport and hauling of loads
US8333392May 1, 2012Dec 18, 2012Wolf Bryan ALightweight plastic sleds for emergency transport and hauling of loads
US8640798Aug 28, 2009Feb 4, 2014Stryker CorporationMotorized sled for stair chairs
WO2009137599A2 *May 6, 2009Nov 12, 2009Stryker CorporationFolding chair cot for use with emergency vehicles
WO2013043261A2 *Jul 31, 2012Mar 28, 2013Stryker CorporationPatient transfer device
Classifications
U.S. Classification297/118
International ClassificationA47C13/00
Cooperative ClassificationA61G1/0237, A61G1/0281, A61G1/0268, A61G1/0225, A61G1/0287, A61G1/0218, A61G1/013, A61G1/017
European ClassificationA61G1/013, A61G1/02, A61G1/017
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Owner name: DESCENT CONTROL SYSTEMS, INC., UTAH
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Effective date: 20070315