Large body stretcher

Information

  • Patent Grant
  • 6568009
  • Patent Number
    6,568,009
  • Date Filed
    Friday, March 23, 2001
    23 years ago
  • Date Issued
    Tuesday, May 27, 2003
    21 years ago
Abstract
A large body stretcher dimensioned to accommodate large-bodied persons and foldable to conserve space. The stretcher provides a patient support surface comprising a first board and a second board that are secured together and foldable along a longitudinal axis. The stretcher may conveniently be secured, via a securing arrangement, to a host cot. The stretcher further provides rotatable backrest portions that permit the backrest of the host cot to be raised in order to assist patients who can benefit from being transported in an upright or seated position. The stretcher further provides a plurality of retaining channels so that the restraining straps of the host cot are available for use with a patient placed upon the large body stretcher. Handholds are provided to allow convenient use of the stretcher as a standalone apparatus.
Description




BACKGROUND OF THE INVENTION




The present invention relates in general to foldable stretchers, and in particular to a foldable large platform stretcher capable of extending over and securing to an ambulance cot in order to accommodate safely a patient with a large body.




Foldable stretchers are often used to transport patients from the scene of an accident to an emergency vehicle, such as, for example, an ambulances or a helicopter. Such stretchers are often dimensioned similar to that of a standard rollable ambulance cot and provide only a patient litter in order to be as lightweight as possible. Therefore, in most situations, the patient is transferred from the stretcher to the rollable ambulance cot in order to safely secure the patient thereon for transport to a medical facility.




However, ambulance cots are not always suited to accommodate the medical needs of persons with large bodies. Often times, it is difficult to place a large-bodied patient in the cot, and sometimes the cot cannot accommodate the large-bodied person at all. In those situations, the portable stretcher is then often placed on top of the ambulance cot in an unsecured or jerry-rigged fashion. Once the patient is loaded into the transport vehicle, even though the ambulance cot is locked into place with the provided securing devices that mate securely with the transport vehicle, there is still a need to better secure the patient within the transport vehicle for safe transport to the medical facility. The lack of a means to safely and securely transport a large-bodied patient can degrade the quality of medical care provided to them.




Further, the compact nature of both conventional foldable stretchers and ambulance cots often provides little extra space for emergency equipment, such as oxygen tanks, intravenous medications, cardio monitors and the like which are required for immediate treatment. These devices are often placed on the empty spaces of the cot's mattress without compromising the patient carried thereon. However, with a large-bodied patient, the lack of available mattress space can lead to distractions to the emergency care provider, clutter in the transport vehicle, and general difficulty during transportation of the patient.




Finally, in those situations when the stretcher is provided on top of the ambulance cot, the ability to prop the patient into an upright or seated position is difficult and often unavailable. The inability of positioning the patient in such a manner can degrade the quality of medical care provided to them.




Accordingly, there is a need for a stretcher adapted to provide a secure and enlarged platform to accommodate large-bodied patients, medical devices and the like. There is also a need for a stretcher which may be used as a standalone apparatus, or which can be mounted easily and securely to an ambulance cot. There is a further need for a stretcher capable of permitting patients to be transported in an upright or seated position.




SUMMARY OF THE INVENTION




These needs are met by the present invention providing a foldable stretcher dimensioned to accommodate large-bodied persons that can be used as a stand-alone stretcher/backboard, or be mounted quickly and securely to an ambulance cot. The stretcher provides a patient support surface comprising a first board and a second board. The first board and the second board are rotatably secured together along a longitudinal side, such that the first portion is foldable over the second portion to conserve space.




The stretcher further provides a securing arrangement that permits the stretcher to be mounted to a host cot. The securing arrangement comprises legs that mate securely with docking ports or receptacle members mounted to the host cot. In one embodiment, the legs are rotatably mounted to the underside of the stretcher such that they may be movable from an extended position and a stowed position. In another embodiment, the legs are removably mounted to mounting channels provided in the stretcher. The stretcher also comprises a backrest portion that, upon securing the stretcher to the host cot, permits the backrest of the host cot to be raised in order to assist patients who can benefit from being transported in an upright or seated position. Additionally, the stretcher comprises a plurality of retaining channels so that separate restraining straps or the restraining straps of the host cot are available for use with a patient placed upon the large body stretcher. Furthermore, handholds are provided to allow convenient use of the stretcher as a standalone apparatus. Finally, an extender board may used to expand the lateral dimension of the stretcher.




In accordance with one embodiment of the present invention, provided is a stretcher attachable to a host rollable cot with a raisable backrest. The stretcher comprises a first board having a first backboard portion and a second board having a second backboard portion. The second board is hinged to the first board along a longitudinal side such that the first and second boards are movable between a first condition in which the first and second boards form a substantially planar patient support surface, and a second condition in which the first and second boards are folded against each other. The first and second backboard portions are rotatably mounted to the first and second boards, respectively, and configured to permit the backrest of the host rollable cot to be raised when the stretcher is provided thereon in the first condition.




In accordance with another embodiment of the present invention, provided is a stretcher comprising a first board having a first plurality of finger and knuckle portions, and a second board having a second plurality of finger and knuckle portions. The second board is hinged to the first board along a longitudinal side such that the first and second boards are movable between a first condition in which the first and second boards are folded against each other, and a second condition in which the first and second boards form a substantially planar patient support surface. When in the second condition, the first finger portions of the first board rest upon the second knuckle portions of the second board and the second finger portions of the second board rest upon the first knuckle portions of the first portion.




In accordance with still another embodiment of the present invention, provided is a stretcher attachable to a host rollable cot with a raisable backrest. The stretcher comprises a first board having a first backboard portion, and a first plurality of finger and knuckle portions. The stretcher further comprises a second board having a second backboard portion, and a second plurality of finger and knuckle portions. The second board is hinged to the first board along a longitudinal side such that the first and second boards are movable between a first condition in which the first and second boards are folded against each other and a second condition in which the first and second boards form a substantially planar patient support surface. When in the second condition, the first finger portions of the first board rest upon the second knuckle portions of the second board and the second finger portions of the second board rest upon the first knuckle portions of the first portion. The first and second backboard portions are mounted to the first and second boards, respectively, and configured to permit the backrest of the host rollable cot to be raised when the stretcher is provided thereon in the first condition.




Other features and advantages of the present invention will be apparent in light of the description of the invention embodied herein.











BRIEF DESCRIPTION OF THE DRAWINGS




The following detailed description of the embodiments of the present invention can be best understood when read in conjunction with the accompanying drawings, where like structure is indicated with like reference numerals, and in which:





FIG. 1

is a front perspective view of a large body stretcher according to the present invention;





FIG. 2

is a back perspective view of the large body stretcher of

FIG. 1

, illustrating an optional structural support arrangement;





FIG. 3

is a front perspective view of a large body stretcher according to the present invention partially folded;





FIG. 4

is a side illustrative view of a large body stretcher secured to a host cot according to the present invention;





FIG. 5

is a section view taken along section line


5





5


illustrating a removably mounted securing leg of a large body stretcher according to the present invention; and





FIG. 6

is an illustration of the large body stretcher of the present invention, illustrating a typical arrangement for an optional lateral extender member.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Front and back perspective views of a large body stretcher


100


according to the present invention are shown by

FIGS. 1 and 2

. The stretcher


100


when fully unfolded in a first condition as shown provides a substantially planar patient support surface


101


that comprises a first board


102


and a second board


104


. First and second hinges


106


and


108


connect the first board


102


and the second board


104


along opposed longitudinal sides


103


such that the first and second boards may fold back against each other to a second condition indicated by the dashed lines in

FIG. 3

, thereby conserving space. For other embodiments, the first board


102


may connect to the second board


104


with other securing arrangements such as, for example, bolting, pinning, screwing and the like.




The first and second hinges


106


and


108


provide structural support to the stretcher when in the fully unfolded condition providing the patient support surface


101


. Additional structural support is provided to the stretcher


100


by the hinged side


103


of each board


102


and


104


having integral finger and knuckle portions


107


and


109


, respectively, which is best illustrated by FIG.


3


. The finger and knuckle portions


107


and


109


alternate such that each of the finger portions


107


of the first and second boards


102


and


104


rests upon a corresponding knuckle portion


109


provided on the opposing board, thereby adding supportive strength and spinal support to the stretcher


100


when positioned in the first condition.




The lateral width of the stretcher


100


is such to permit the stretcher to maneuver through common doorways, and is preferably about 34 inches. Additionally, such a lateral dimensioning would also permit the stretcher


100


to fold and easily stow, such as, for example, in an existing backboard compartment in a typical ambulance. Furthermore, while the stretcher


100


is generally suited for carrying large persons, the extra lateral dimensions of the platform make it ideally suited to providing additional surface area for equipment, including cardio equipment, intravenous equipment, and the like. Often times, extra equipment is required in the treatment of a patient. Where hoses, tubes, electronic devices and the like are used, it is preferable to place the equipment as near the patient as possible, to avoid inadvertently bumping into such equipment by the emergency care givers while working in the narrow constraints of an emergency vehicle. Moreover, it should become apparent to those skilled person skilled in related art, that the stretcher


100


may also be used advantageously as a field table, such as used for triage, operations, decontaminations, and the like.




The longitudinal length can be selected to meet the needs of the specific user requirements, and further, to meet any specialized needs of a host rollable cot


126


(FIG.


4


), such as those carried by an ambulance, such that the stretcher


100


may mount thereon. For example, a preferably length of approximately 76 inches would be suitable for a number of applications.




The first and second boards


102


and


104


each include a backrest portion


110




a


and


110




b


, respectively. Each backrest portion


110




a


and


110




b


is rotatably mounted to its respective board


102


or


104


at an end via a hinging arrangement


111


. The hinging arrangement


111


permits each backrest portion to rotate about a lateral axis from a position flush with its respective board as illustrated in

FIG. 1

, to a raised position as illustrated in

FIG. 4. A

supportive edge


113


(

FIG. 2

) of each board


102


and


104


, and integral finger and knuckle portions


107


and


109


of each backrest portion


110




a


and


110




b


operate together to prevent the backrest portions from rotating below the patient support surface


101


. Additionally, the supportive edge


113


and the finger and knuckle portions


107


and


109


provide support to the backrest portions when the stretcher


100


is in the fully unfolded condition.




With the stretcher


100


fully unfolded, the backrest portions


110




a


and


110




b


together form a rotatable backrest


110


. As illustrated by

FIG. 4

, the rotatable backrest


110


permits the host cot's backrest


127


to be placed in a raised position when the stretcher


100


is secured to the host cot


126


such that a patient carried thereon may be positioned in an upright or seated position. In another embodiment, each backrest portion


110




a


and


110




b


is removably attached to its respective board such that it maybe removed, if desire, to permit the backrest


127


of the host cot


126


to be raised through the space therein provided in the stretcher


100


.




Preferably, the maximum load capacity for the platform


100


is about 600-pound. In order to allow attendants to carry a large-bodied patient of about 600-pounds upon the patient support surface


101


, the stretcher


100


contains a plurality of handholds


114


spaced around and adjacent to the stretcher's periphery


112


. For other embodiments, the maximum load capacity and number of handholds can vary depending upon the required application and stretcher dimensions. It is to be appreciated that the handholds


114


are provided adjacent the patient support surface


101


such that the handhold


114


are spaced a distance for the work surface upon which the stretcher is supported. Such a handhold arrangement allows the attendants to grasp more easily the handholds


114


and to gain a mechanical advantage for lifting the stretcher


100


. In other embodiments, integral footpads positioned along the back or underside of the stretcher


100


may be provided to suspend the stretcher in a slightly raised position with respect to the work surface.




For applications where load capacities are expected above 600 pounds, the stretcher


100


may be provided with movable crossbars in order to further strengthen the stretcher


100


while in the fully unfolded condition. In such an embodiment, the crossbars are positioned substantially laterally along the stretcher where extra support is needed, and are indicated by dashed lines


118


and


120


in

FIG. 2. A

slot or channel (not shown) can be provided in the boards


102


and


104


to slidably mount the crossbars


118


and


120


to the stretcher


100


. In this manner, the crossbars may be moved laterally to extend across the adjacent board when the stretcher


100


is in the fully unfolded condition. The crossbars


118


and


120


can then be secured into place in a conventional manner such as a pin, bolt, or clasp to provide added support to the stretcher


100


.




Referring to

FIGS. 1 and 2

, the stretcher


100


includes a plurality of throughbore-pairs or retaining channels


116


for receiving or passing through straps and like restraining devices while the stretcher


100


is secured to the host cot


126


. The retaining channels


116


can be placed anywhere along the surface of the stretcher


100


as desired. The number of retaining channels


116


utilized and the positioning will be dependant upon factors such as the positioning of restraints on the host cot


126


(FIG.


4


), and of the needs of the patient.




Referring to

FIG. 4

, the stretcher


100


further includes a securing arrangement


121


to allow the platform


100


to mount to the host cot


126


. In one embodiment, the securing arrangement


121


comprises a plurality of legs


122


rotatably mounted to the underside of the stretcher


100


. In this embodiment, the legs


122


fold from a stowed position substantially parallel to the stretcher


100


, illustrated by the dashed lines, to an extended position, which places the legs


122


substantially perpendicular to the stretcher


100


as illustrated in FIG.


4


. Any suitable locking arrangement can be used to secure the legs


122


in both the extended and stowed positions. With the legs


122


placed in the extended position, the stretcher


100


may then be advantageously releasable mounted to the host cot via receptacle members


128


provided on the host cot


126


.




Referring to

FIG. 2

, in another embodiment, the securing arrangement


121


comprises a plurality of removable Y-shaped legs


122


which are locatable by first ends


123


in mounting channels


124


of the stretcher


100


. Second ends


125


of the legs


122


mated with the receptacle members


128


either provided to the host cot


126


directly or secured to the host cot through the use of clamps, bolts or the like. Preferably, the second end


125


of each leg


122


has a dovetail configuration which mates to an oppositely shaped socket


127


of the receptacle member


128


, and secures therein, such as with pins, latches, and the like.




In a preferred use, the legs


122


are mounted first to the host cot


126


, via the provided receptacle members


128


. Next, the stretcher


100


is positioned down on the legs


122


by looking down through the mounting channels


124


from the support surface


101


of the stretcher


100


. As shown in

FIG. 5

, illustrating a cross section of the stretcher and one of the legs


122


taken along line


5





5


, the leg


122


is accommodated in its respective mounting channels


124


such that its first end


123


is engaged between its forks


131


by a brace member


130


of the stretcher. As illustrated in

FIG. 1

, the brace member


130


spans the width of the mounting channel


124


. A securing bar


132


is used to releasably secure the stretcher


100


to the leg


122


. It is to be appreciated that for this embodiment, all the legs


122


are secured to the stretcher in the same manner as described above.




In a secure position, the securing bar


132


extends through a securing cavity


134


provided in the leg


122


. The securing bar


132


holds the leg


122


fast to the stretcher


100


due to its oval or racetrack shape being unable to slip between a channel


133


provided between the forks


131


of the leg. In a release position, the securing bar


132


is rotated about ninety degrees, which is indicated by the dashed-lines, such that the securing bar


132


may slip through the channel


133


, thereby releasing the leg


122


from the mounting channel


124


. It is to be appreciated that each board


102


and


104


includes a securing bar


132


that may be manually moved between the secure position and the release position, via included actuators


136


(FIG.


1


). Moving one of the actuators


136


from the illustrated secured position to the release position, illustrated by the dashed lines in

FIG. 1

, rotates the associated securing bar


132


about ninety degrees, thereby permitting the removal of all the legs


122


accommodated within the mounting channels


124


on the respective board


102


or


104


. Accordingly, moving the actuators


136


to the secured position, will secure all the legs


122


accommodate within the mounting channels


124


to the stretcher


100


.




Referring to

FIG. 6

, a lateral extender board


138


having also a plurality of finger and knuckle portions


107


and


109


may be provided to extend the dimensions of the stretcher


100


for situations in which an even larger area patient support surface


101


(

FIG. 1

) is required. In this embodiment, the hinge


106


(

FIG. 2

) is configured to allow the first board


102


to separate from the second board


104


through the removal of a retaining pin or the like. Additionally, alternative means can be used to releasably secure the first board


102


to the second board


104


including bolts, brackets, clamps, and the like. Preferably, in this embodiment the hinge


106


allows for rapid conversion by releasably securing and permitting the boards


102


and


104


to extend along the longitudinal side


103


(

FIG. 3

) similar in fashion to the method used to add a centerboard to enlarge a dinning room table. Accordingly, telescoping member lateral support members


139


permit the first board


102


and second board


104


to be extended and retracted. After releasing a locking device holding the boards together along the longitudinal side


103


, by applying a force on the first board


102


in the direction of arrow


144


, and applying a force to the second board


104


in the direction of arrow


146


, the lateral extender board


138


may be placed between the boards. Then transitioning the first and second boards


102


and


104


in the direction of arrows


140


and


142


, respectively, the longitudinal edges of the lateral extender board


138


are thereby secured between the boards. Re-securing the locking device will prevent further lateral movement of the boards


102


and


104


while the lateral extender board


138


is in use. In this manner the stretcher


100


can have a nominal lateral dimension, such as for example, of approximately 34 inches in an unfolded position, which then can be extended laterally, such as for example, by an additional 10 inches by inserting lateral extender board


138


.




The boards


102


and


104


, the backrest portion


110




a


and


110




b


, and the lateral extender boar


138


of the stretcher


100


are made of a molded non-porous material, such as a polymer, and preferably, polyethylene plastic or other suitable material and utilizes a rotational molding procedure. It is to be appreciated that using rotational molding permits the formation of both a lightweight and durable stretcher


100


. Additionally, it is to be appreciated that forming the portions of the stretcher


100


by rotation molding also has a number of inherent design strengths, such as consistent wall thickness and strong corners that are virtually stress free. Furthermore, should additional strength be required, reinforcing ribs can be designed and molded into each portion of the stretcher. Alternatively, the portions of the stretcher


100


may be blow molded, injection molded, and/or constructed of metal.




In operation, where an emergency care provider recognizes the need for a large platform, the stretcher


100


is removed from its storage location; for example, a backboard storage compartment provided on an emergency transport. The stretcher


100


is then transported to its desired location. It should be pointed out that the present invention is useable as a standalone stretcher, or as a platform extender for a host cot


126


. Therefore, the present invention can be unpacked and immediately assembled to the host cot


126


by unfolding the stretcher


100


, positioning it over the host cot


126


, and then securing the platform to the host cot


126


using the provided securing arrangement


121


.




Alternatively, the stretcher


100


may be transported to the desired location by carrying it in either the folded, or the fully unfolded condition. Upon attaining the desired location, if not already completed, the stretcher


100


is unfolded by unfolding the first portion


102


from the second portion


104


. The patient is placed upon the platform


100


, secured in place with restraining straps connected or passing through the retaining channels


116


, and then lifted by grasping the stretcher


100


along handholds


114


.




Upon returning to the ambulance, the stretcher is secured to the host cot


126


using the provided securing arrangement


121


. Once the stretcher is secured to the host cot


126


, the cot is loaded into the ambulance or other transportation vehicle. Because the stretcher


100


does not interfere with or inhibit locking devices used to secure the host cot


126


within the ambulance, such locking devices may be used in order to transport safely and effectively the patient upon the connected stretcher


100


and host cot


126


to an emergency facility.




In the foregoing specification, the invention has been described with reference to specific exemplary embodiments thereof. It should be appreciated that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention as set forth in the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.



Claims
  • 1. A stretcher attachable to a host rollable cot with a raisable backrest, said stretcher comprising:a first board having a first backboard portion, a continuous exterior side edge, and a sectioned interior side edge, said first backboard portion forming a section of said interior side edge; a second board having a second backboard portion complimentary to said first board and said first backboard portion, said second board is hinged to said first board along at least a portion of said interior side edge such that said first and second boards are movable between a first condition in which said first and second boards form a substantially planar patient support surface, and a second condition in which said first and second boards are folded against each other, and said first and second backboard portions are rotatably mounted to said first and second boards, respectively, and configured to permit the backrest of the host reliable cot to be raised when said stretcher is provided thereon in said first condition.
  • 2. The stretcher according to claim 1, wherein said first and second boards each provide a plurality of finger and knuckle portions along said interior side edge.
  • 3. The stretcher according to claim 1, wherein said first and second boards each provide a plurality of handholds.
  • 4. The stretcher according to claim 1, wherein said first and second boards each provide a plurality of retaining channels.
  • 5. The stretcher according to claim 1, further comprising a plurality of rotatably mounted legs, said legs are movable between an extended position that places said legs perpendicular to said stretcher when in said second condition and a retracted position which places said legs in parallel with said stretcher.
  • 6. The stretcher according to claim 1, wherein said first and second boards each provide a plurality of mounting channels and said stretcher further include a plurality of legs removably mounted in said mounting channels.
  • 7. A stretcher attachable to a host rollable cot with a raisable backrest, said stretcher comprising:a first board having a first backboard portion; a second board having a second backboard portion, said second board is hinged to said first board along a longitudinal side such that said first and second boards are movable between a first condition in which said first and second boards form a substantially planar patient support surface, and a second condition in which said first and second boards are folded against each other, wherein said first and second backboard portions are rotatably mounted to said first and second boards, respectively, and configured to permit the backrest of the host rollable cot to be raised when said stretcher is provided thereon in said first condition, wherein said first and second boards each provide a plurality of mounting channels and said stretcher further include a plurality of legs removably mounted in said mounting channels, and wherein said first and second boards each further comprise a securing bar manually moved between a secure position and a release position, said secure position engages said legs accommodated in said mounting channels with said securing bar, and said release position disengages said securing bar from said legs accommodated in said mounting channels.
  • 8. A stretcher comprising:a first board having a first plurality of finger and knuckle portions; and a second board having a second plurality of finger and knuckle portions and hinged to said first board along a longitudinal side such that said first and second boards are movable between a first condition in which said first and second boards are folded against each other, and a second condition in which said first and second boards form a substantially planar patient support surface, wherein said first finger portions of said first board rest upon said second knuckle portions of said second board and said second finger portions of said second board rest upon said first knuckle portions of said first portion, wherein said first and second boards each provide a plurality of mounting channels and said stretcher further comprises a plurality of legs removably mounted in said mounting channels, and wherein said first and second boards each further include a securing bar manually moved between a secure position and a release position, said secure position engages said legs accommodated in said mounting channels wit said securing bar, and said release position disengages said securing bar from said legs accommodated in said mounting channels.
  • 9. A stretcher attachable to a host rollable cot with a raisable backrest, said stretcher comprising:a first board having a first backboard portion, and a first plurality of finger and knuckle portions; and a second board having a second backboard portion, and a second plurality of finger and knuckle portions, said second board is hinged to said first board along a longitudinal side such that said first and second boards are movable between a first condition in which said first and second boards are folded against each other and a second condition in which said first and second boards form a substantially planar patient support surface, wherein said first finger portions of said first board rest upon said second knuckle portions of said second board and said second finger portions of said second board rest upon said first knuckle portions of said first portion, wherein said first and second backboard portions are mounted to said first and second boards, respectively, and configured to permit the backrest of the host rollable cot to be raised when said stretcher is provided thereon in said first condition, wherein said first and second boards each provide a plurality of mounting channels and said stretcher further comprises a plurality of legs removably mounted in said mounting channels, and wherein said first and second boards each further include a securing bar manually moved between a secure position and a release position, said secure position engages said legs accommodated in said mounting channels with said securing bar, and said release position disengages said securing bar from said legs accommodated in said mounting channels.
  • 10. A stretcher and cot assembly comprising:a stretcher, wherein: said stretcher comprises a first board and a second board; said second board is secured to said first board along a longitudinal side such that said first and second boards are movable between a first condition in which said first and second boards form a substantially planar patient support surface, and a second condition in which said first and second boards are folded against each other; and said stretcher further comprises a plurality of mounted legs, said legs are rotatably mounted and movable between an extended position that places said legs perpendicular to said stretcher when in said second condition and a retracted position which places said legs in parallel with said stretcher; and a cot having at least one receptacle member disposed to allow one of said plurality of mounted legs to be secured therein such that said stretcher may be releasably mounted to said cot.
  • 11. The stretcher and cot assembly according to claim 10, wherein said cot has a plurality of receptacle members each disposed to allow one of said plurality of mounted legs to be secured therein.
CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the following U.S. Provisional Application: Ser. No. 60/191,705 for Large Body Stretcher, filed Mar. 23, 2000.

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