BACKGROUND OF THE INVENTION.
[0001] This invention relates to a stretcher (being an appliance for carrying a disabled
person) and, more particularly but not exclusively, is concerned with a portable stretcher
useful to emergency and rescue services.
[0002] There have been a number of prior proposals for stretchers to be used by emergency
and rescue services. Stretchers of the "carrying sheet" type are readily transportable
but are limited in their ability to provide rigid support over the full width and
length of a supine human body. Those previously proposed portable stretchers which
would provide ample support are too large and heavy to be readily transportable over
long distances by a single human bearer.
BRIEF SUMMARY OF THE INVENTION.
[0003] The present invention seeks to provide a fully supportive stretcher which is, at
the same time more readily transportable than the prior proposals.
[0004] According to a first aspect of the present invention there is provided a stretcher
comprising means for providing a rigid surface large enough to provide support to
a supine human body over substantially the entire width and length of the body, and
an inflatable body cushioning means which is situated between the rigid surface and
the supine human body in use of the stretcher.
[0005] The combination of a rigid surface and an inflatable cushion combines lightness and
strength, and thereby failitates transport of the stretcher, while empty, by a single
human bearer.
[0006] The means for providing a rigid surface is preferably constituted by (i) a body board
made up from at least three rigid body support board portions which extend in a transverse
direction across the full width of the board and in a longitudinal direction along
a portion of the length of the board; and (ii) means for limiting movement of the
board portions relative to one another to movement between a compact, transport disposition
of the stretcher and a flat, useful disposition of the stretcher.
[0007] The compactness of the transport disposition makes it possible to provide a stretcher
light enough and small enough to be carried easily by one person, and this may be
so even if no inflatable cushioning means is provided. Thus, according to a second
aspect of the invention there is provided a stretcher characterised in that it comprises
a body board made up from at least three rigid body support board portions which extend
in a transverse direction across the full width of the body board and in a longitudinal
direction along a portion of the length of the board, and means for limiting movement
of the board portions relative to one another to movement between a compact transport
disposition of the stretcher and a flat useful disposition of the stretcher.
[0008] The parts of the stretcher are preferably so shaped that, when the stretcher is in
the transport disposition, the entire stretcher can be arranged as a back-pack, which
is preferably such that no dimension exceeds one-third of the length of the stretcher
when in use. Preferably the board portions are circumjacent the cushioning means,
in the transport disposition, thereby affording some protection to the inflatable
cushioning means in transport.
[0009] Preferably the support board portions are connected by hinge formations, which can
be of fabric, so retaining the body support board as a single component which can
be folded into a compact configuration. Thus, a pack having a width which is similar
to that of the stretcher, a thickness X approximately one-tenth of the length of the
stretcher and a length Y approximately one-quarter of the length of the stretcher
can be provided with a body support board having a central portion of length (along
the length of the stretcher) X to which is joined by hinges two adjacent board portions
of length Y, and then two further portions of length no more than X. In particular,
these two further portions can be of length X/2 and connected to two end portions
of the body support board having a length no greater than Y. If the two ends of such
a board are folded in to the middle of the board then a pack of the same width as
the support board and with X and Y as its other two major dimensions, will be formed.
[0010] Conveniently the body support board portions are made from a composite material of
fibres set in a resin matrix in order to provide the maximum available stiffness consistent
with a light weight.
[0011] Stiffening means may be employed to limit relative movement of the board portions
when the stretcher is in use. In one embodiment, not at present preferred, but described
in British Patent Application No. 8117596, the priority of which is claimed herein,
these stiffeners are of 25 mm square section aluminium alloy tube and are attached
to the body support board so that they are not lost when the stretcher is dismantled.
None of the stiffeners is longer than one-third of the length of the stretcher and,
where it is convenient to connect together the stiffeners for use of the stretcher,
this can be effected by the use of retractable inserts housed within the ends of the
stiffener tubes.
[0012] It will usually be advantageous to provide buoyancy tubes along the flank edges of
the body support board, so that the stretcher is capable of supporting an injured
person on the surface of a body of water. Conveniently the lower surfaces of the buoyancy
tubes are resistant to abrasion and are faired at one end at least of the stretcher
so that the stretcher is more readily suitable to be handled as a sledge in use i.e.
is adapted for sledging. Again, it will often be convenient to nip the buoyancy tubes
in at the waist area to restrict the overall width of the stretcher (for example,
to not more than one metre so that the stretcher can readily be passed through doorways)
and to provide a convenient location point for the connection between the buoyancy
tubes and the body support board.
[0013] Advantageously the upper surface of the body support board is provided with an inflatable
mattress and has a sufficient number of straps or bindings to enable the necessary
restraint to be applied to the injured person on the stretcher. It is useful to divide
the mattress into a trunk cushion and a head cushion, and to provide means for establishing
a degree of inflation of the head cushion different from that of the trunk cushion.
Usually a survival cover or sheet will be provided to extend over the body support
board for covering the injured person and conveniently this is in two halves connected
by a zip fastener running centrally along the length of the sheet or cover.
BRIEF DESCRIPTION OF THE DRAWINGS.
[0014] For a better understanding of the invention, and to show more clearly how the same
may be carried into effect, reference will now be made, by way of example, to the
accompanying drawings in which:
Fig. 1 is a plan view of one embodiment of a stretcher according to the invention,
when inflated and in its flat disposition, but with a survival cover removed for reasons
of clarity;
Fig. 2 is a side elevation of the stretcher of Fig. 1 but with the survival cover
included;
Fig. 3 is a plan view of the body board of the stretcher with one stiffener removed
in order to show slots in the body board;
Fig. 4 is a side elevation of the stretcher when it is in its compact, transport disposition;
Fig. 5 is a diagrammatic cross-section of the stretcher, on the line V-V shown in
Fig. 1;
Fig. 6-is an enlarged detail of Fig. 5 showing the attachment of one stiffener element
to an associated portion of the body board; and
Fig. 7 is an enlarged detail of Fig. 4 showing the construction of one of the fabric
hinges connecting two adjacent portions of the body board of the stretcher.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT.
[0015] Referring to Figs. 1 and 2, the trunk and legs of the body of an injured person 10
is borne on an inflatable mattress 11 carried between two large buoyancy tubes 12
and 13. The head of the patient 10 rests upon a V-shaped headrest cushion 14, and
his body is covered by a laminated survival cover 15 which incorporates leaves of
the so-called "Space Blanket" material for resisting loss of heat from the patient
10. Also provided, but not shown, is a transparent visor for covering the head of
the patient 10, when necessary. The survival cover 15 has a centrally placed zip fastener
16 running the entire length of the cover, and tags 17 which engage studs on the tubes
12 and 13 with a snap action.
[0016] Fig. 1 shows that the main buoyancy tubes 12 and 13 are connected by a front thwart
support tube 18 and rear tube 19. This rear tube carries a main inflatable valve 20
through which supplies of compressed air or, if desired, compressed carbon dioxide
gas, may be introduced into the inflatable cavities of the stretcher. A bottle 21
of sufficient compressed gas to inflate the stretcher may be secured to the rear tube.
[0017] The gas passes directly from the tube 19 into the main buoyancy tubes 12 and 13 and
the front thwart support tube 18, but indirectly, through a mattress inflation cock
22, into the mattress 11 and the headrest 14. Between the mattress 11 and headrest
14 there is a non-return valve shown in the drawing purely schematically at 39. The
amount of air in the headrest is controllable by a deflation valve 23, and the amount
of air in the mattress 11 by a mattress deflation valve 24. With this arrangement,
it is possible to deflate the mattress 11 entirely, while all the other inflatable
components of the stretcher remain fully inflated, and this may be useful for spinal
patients or where some other form of mattress is to be used.
[0018] The front thwart support tube 16 carries a pressure relief valve 25 and a deflation
plug 26. Around the periphery of the stretcher there are provided a number of lifting
rings and handles 27.
[0019] Fig. 1 shows one possible arrangement of straps and harness bonded to the inflatable
mattress 11, the main buoyancy tubes 12 and 13 and the body support board beneath
the mattress 11 and described further hereinbelow, to provide the necessary restraint
for an injured person lying on the stretcher. Conveniently, the various straps and
harness incorporated quick release buckles 28. The straps may therefore comprise a
head strap 29, a chest strap 30, groin straps 31 and 32 a knee strap 33 and an ankle
strap 34, adjustable, diagonal body-securing harness straps 35 and 36, a plurality
of leg-securing loops 37 and several traction loops 38.
[0020] As best seen in Fig. 2, the ends of the buoyancy tubes 12 and 13 are faired into
a smoothly rounded shape to facilitate "sledging" i.e. dragging, the stretcher over
the ground. The ground-contacting surfaces of the stretcher are protected against
abrasion if such use is contemplated. The illustrated embodiment is adapted to be
safely towed over a water surface, as the stretcher floats thereon.
[0021] Fig. 3 shows that the body support board 40 is made up of a relatively short central
board portion 41 flanked by two large portions 42 and 43, flanked in turn by two rather
short portions 44 and 45 and then two equal sized end portions 46 and 47, the adjacent
portions of the board being connected to one another by fabric hinges 48 and together
providing a board having a length of nearly 2 m and a width of approximately 40 cms.
[0022] The portion 42 has a pair of slots 49 and 50, the portion 43 has a pair of slots
51 and 52 and the end portion 46 (which underlies the headrest 14) has a pair of slots
53 and 54. In each of the slots is slidably movable an aluminium slide member 55 to
60 respectively. Connected to the slide member 55 by a fabric hinge 61, the slide
member 57 by a fabric hinge 62 and the slide member 59 by a fabric hinge 63 is a stiffener
string generally referenced 64. The hinges allow the string to pivot through a right
angle between a relaxed disposition flat on the board 40 as shown in Fig. 3 and a
standing disposition perpendicular to the board 40 as shown in Fig. 6, referred to
hereinbelow.
[0023] The string 64 comprises an end element 65 of marine grade plywood connected to the
hinge 61 and by a strong brass hinge 66 to a first centre element 67 which overlies
the centre board portion 41. This element 67 is connected by a similar brass hinge
68 to a compensating element 78 which overlies the board element 43. A short element
69 is connected by a brass hinge 70 to the compensating element 78 and by another
brass hinge 71 to an end element 72 itself connected to the fabric hinge 63.
[0024] A string which is mounted to the slide members 56, 58 and 60 is similar to the string
64 and a mirror image of it. It is omitted from Fig. 3 the better to show the slide
members 56, 58 and 60.
[0025] The way in which the strings function will become clearer from the description of
Fig. 4 which follows. The length of the compensating element 78 is variable by a small
extent, as is shown diagrammatically in Fig. 3 by a male member 73 of a first portion
74 of the compensating element which is slidable in a channel 75 in a second portion
76 of the element 78.
[0026] Fig. 4 shows the body board 40 and stiffener string 64 in the compact, transport
disposition of the stretcher, and it is believed that inspection of the reference
numbers will reveal the manner in which the board and string is folded. It will be
appreciated that the brass hinges 66, 68, 70 and 71 each fold at the position of one
of the fabric hinges 48 connecting adjacent body board portions, and that the compensating
element 78 serves to secure sufficient variation in the distance separating the brass
hinges 68 and 70 to allow the body board 40 to move between its folded, compact disposition
and its flat disposition.
[0027] Turning now to Fig. 5, it can be seen that the main buoyancy tubes 12 and 13 are
nipped in at the waist thereof by H-section reeds 80 and 81 respectively. It is preferable
that the end flanges 82 of the reeds are secured to the outer surface of the buoyancy
tubes, and then further secured by fabric holding covers 83 as shown in the drawing.
An alternative, but less preferred, arrangement would be to secure end flanges of
the reeds 80 and 81 to the interior surface of the buoyancy tubes 12 and 13.
[0028] Strips 84 of material secure the buoyancy tubes 12 and 13 to the long edges of the
body support board 40 of the stretcher. The board 40 is supported as described above
by stiffener strings 64 and 85, and carries the inflatable mattress 11 of the stretcher
on its upper surface. The construction of the mattress 11, as shown in Fig. 5, is
conventional and need not be described further herein. Above the mattress 11 is shown
the survival cover 15. Fig. 5 shows sheets of abrasion-resistant material 86 may be
bonded to the lower surfaces of the buoyancy tubes 12 and 13 to resist damage to the
gas-tight construction of the tubes 12 and 13 during sledging of the stretcher.
[0029] The detail view of Fig. 6 shows the stiffener element 65 secured to the slide member
55 by the fabric hinge 61 which comprises a wide strip 87 and a narrow strip 88 of
fabric which together flank the lower longitudinal edge 89 of the element 65 and extend
through a slot 90 defined by a slotted element 91 of the slide member 55. The lower
edges of the strips 87 and 88 are secured between a downward-facing surface of the
slotted element 91 and an upward-facing surface of a facing element 92 of the slide
member 55.
[0030] The slots and slide members in the body board are protected from contact with dirt
or water from below the body board by waterproof protective covers 93 of polyvinylchloride
bonded to the lower surface of the body board 40 and within which the slide members
55 to 60 can move along their respective slots.
[0031] It will be appreciated from study of Fig. 6 that if the mattress 11 is deflated,
the stiffener strings 64 and 85 can take up (arrow f) the relaxed disposition, flat
above the board 40 and overlying an edge of the deflated mattress 11, and that as
the mattress 11 is inflated the strings will be pushed into the standing disposition
shown in Figs. 5 and 6.
[0032] In fact, inflation of the stretcher from the compact disposition of Fig. 4 to the
flat disposition of Figs. 1 and 5 can be automatic, the inflation of the mattress
11 first urging the body board 40 to open out flat and then urging the stiffener strings
to assume their standing disposition in which, it will be appreciated, they are each
sandwiched between one of the flank tubes 12 and 13 and the mattress 11. This sandwiching
helps to keep the stiffener strings 64 and 85 properly upright, and ensures that the
fabric hinges 61 are not required to withstand an unbalanced pressure from the inflated
mattress 11 during use of the stretcher, thereby protecting the fabric hinges 61 to
63 against undue tension and wear.
[0033] Fig. 7 shows one of the fabric hinges 48 when fully open. Each hinge has two fabric
hinge members 90 each bonded to two adjacent portions of the body board 40 and connected
to one another by a centre stitch 91. Short lengths of fabric holding tape 92 cover
the area of the hinge and, in particular, the exposed surface of the centre stitch
91.
[0034] It will be appreciated that the flank tubes 12 and 13 provide a degree of stiffness
in the illustrated embodiment, so that the stiffener strings need not extend towards
the foot of the body board 40 far enough to overlie the body board portions 45 and
47.
[0035] It will further be appreciated that the flank tubes 12 and 13, when deflated, can
be folded to overlie the body board 40 so that, in the transport disposition of the
stretcher, the body board surrounds and protects the other components of the stretcher.
1. A stretcher characterised in that it comprises means (40,64) for providing a rigid
surface large enough to provide support to a supine human body over substantially
the entire width and length of the body, and an inflatable body cushioning means (11)
which is situated between the rigid surface and the prone human body in use of the
stretcher.
2. A stretcher as claimed in claim 1 characterised in that the means for providing
a rigid surface comprises a body board made up from at least three rigid, body support
board portions (41,42,43,44,45,46 and 47) which extend in a transverse direction across
the full width of the body board and in a longitudinal direction along a portion of
the length of the board, and means (48,64) for limiting movement of the board portions
relative to one another to movement between a compact, transport disposition of the
stretcher and a flat, useful disposition of the stretcher.
3. A stretcher as claimed in claim 2 characterised in that, in the compact transport
disposition, the stretcher takes the form of a pack to be carried on the back of a
single human bearer.
4. A stretcher as claimed in claim 3 characterised in that the board portions are
circumjacent the body cushioning means (11) when the stretcher is in said compact
transport disposition thereby affording some protection to the cushioning means.
5. A stretcher as claimed in any one of claims 2, 3 and 4 characterised in that the
means for limiting movement of the board portions comprises a hinge (48) between each
portion and the adjacent portion or portions along the length of the board, and stiffening
means (12, 13 and 64) for resisting downward movement of the or each board portion
separating end portions of the board, when the stretcher is in use and supported at
its ends above the ground.
6. A stretcher as claimed in claim 5 characterised in that the stiffening means comprises
a pair of stiffening strings (64), each of which strings is located along an opposed
longitudinal edge of the board board when the stretcher is in said useful disposition.
7. A stretcher as claimed in claim 6 characterised in that each of the stiffening
strings comprises a line of rigid string elements (65,67,78,69,72), each of which
elements is connected to one of the board portions for movement of the element relative
to the portion between a standing disposition and a relaxed disposition, the said
string elements being hingedly connected to one another with the pivotal axis of the
hinges lying perpendicular to the plane of the body board when the string elements
are in said standing disposition, and in a plane lying parallel to the plane of the
body board when the string elements are in said relaxed disposition, whereby the strings
provide a stiffening function only when they are in said standing disposition, offering
no resistance to movement of the body board portions from the useful disposition to
the transport disposition when they are in said relaxed disposition.
8. A stretcher as claimed in claim 7 characterised in that the strings are disposed
along the longitudinal edges of the cushioning means, and on an upper face of the
body board, and overlie the deflated cushioning means in the relaxed disposition,
so that inflation of the cushioning means (11) urges the strings to move from the
relaxed disposition to the standing disposition.
9. A stretcher as claimed in any one of the preceding claims characterised in that
the body cushioning means comprises a trunk cushion (11) and a head cushion (14),
and in that means (23,24 and 39) are provided for establishing a chosen degree of
inflation of the head cushion different from that of the trunk cushion.
10. A stretcher as claimed in any one of the preceding claims characterised in that
it includes inflatable flank tubes (12 and 13), one on each side of the body board.
11. A stretcher as claimed in claim 10 or 11 characterised in that the flank tubes
are nipped in (81) at a waist area, thereby to restrict the overall width of the inflated
stretcher.
13. A stretcher as claimed in any one of claims 10 to 13 as dependent upon claim 8
characterised in that each of the strings (64) is held in the standing disposition
sandwiched between the cushioning means and one of the flank tubes.
14. A stretcher as claimed in any one of the preceding claims characterised in that
it includes body binding straps (29-37) and a waterproof, heat insulating flexible
body cover (15).
15. A stretcher characterised in that it comprises a body board (40) made up from
at least three rigid body support board portions (41-47) which extend in a transverse
direction across the full width of the body board and in a longitudinal drection along
a portion of the length of the board, and means (48,64) for limiting movement of the
board portions relative to one another to movement between a compact transport disposition
of the stretcher and a flat useful disposition of the stretcher.