Combination ambulance cot and chair

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No. 60/150,466, filed Aug. 24, 1999, which is incorporated by reference.

BACKGROUND OF THE INVENTION

The present invention relates to reclinable ambulance cots used to load patients into the back of an ambulance. More particularly, the present invention relates to a reclinable ambulance cot used to load a patient into the back of an ambulance, wherein situating the cot into a fully-reclined position elevates a loading end of the cot to a height which facilitates the loading of the reclined cot and a patient situated thereon into the ambulance.

In transporting emergency patients from their homes to a hospital for treatment, it is oftentimes necessary to remove the patient from his home using an ambulance cot, such as a stretcher, or the like, wherein the patient is situated thereon in a generally supine position. As well known in the art, such cots are typically provided with an undercarriage having a rollable base which facilitates transportation of the patient situated upon the cot to an ambulance parked near the patient's home. The undercarriage may be collapsed, thereby permitting the cot, its undercarriage, and the patient situated thereon to be rolled into the back of the ambulance in a fully-reclined position for transportation to the hospital.

However, in removing the patient from his home, it is sometimes difficult for paramedics to reach the patient with a fully-reclined cot, such as those of the prior art. Particularly, it is difficult for paramedics to traverse stairs to/from a second floor of the patient's home with a fully-reclined cot, or where the patient's home includes narrow hallways and doorways, through which maneuvering of a fully-reclined cot is extremely difficult, and sometime, impossible. In such situations, it is desirable for the cot to have a reduced “footprint,” such as that provided by a wheelchair or the like, to facilitate maneuvering of the cot and of a patient situated thereon through the patient's home. Once the cot has been removed to a location free from any obstructions of the patient's home, such as, to a location near the back of the ambulance, it is desirable for the cot to be fully-reclinable to facilitate rolling the cot into the back of an ambulance.

Accordingly, there is a need to provide a reclinable ambulance cot which is movable between a fully-reclined position, where a patient situated thereon is resting in a generally supine position, and a chair position, where a patient situated thereon is in a generally upright, sitting position. U.S. Pat. No. 3,289,219 to Ferneau, et al. is illustrative of attempts made in the prior art to provide a combined ambulance cot and rolling chair which is movable between a reclined position and a chair position.

However, it has been observed that prior art reclinable ambulance cots do not provide an elevated loading end which is sufficient in height to facilitate rolling of the fully-reclined cot into the back of the ambulance, and more particularly, into the back of an ambulance which has a high transport deck in excess of 30 inches above the ground. With such prior art cots it is oftentimes necessary for one paramedic to lift the loading end of the fully-reclined cot to an elevation sufficient to permit rolling of the cot into the back of the ambulance while another paramedic pushes the cot into the back of the ambulance. It should be appreciated by those of reasonable skill in the art that loading a patient situated upon a fully-reclined cot into the back of an ambulance in this prior-art manner is difficult, for example, for the paramedics lifting the cot. Furthermore, such lifting increases the risk of physical injury to both the carried patient and the lifting paramedics.

Accordingly, there is also a need to provide a reclinable ambulance cot which is movable between a chair position and a fully-reclined position in which a loading end of the fully-reclined cot is elevated to a height that permits rolling of the reclined cot into the back of an ambulance, and in particularly, into the back of an ambulance with a high deck without the need for additional lifting of the cot by paramedics.

Moreover, it has been observed that prior art reclinable ambulance cots do not easily transition from the chair position to the fully-reclined position. Due to the typically provided ratcheting mechanism on such prior art cots, paramedics must pull up and then lower the cot into its reclined position. This lowering operation with these prior art cots is jarring which can add further discomfort to the patient.

Accordingly, there is also a need to provide a reclinable ambulance cot which transitions smoothly between the chair~position and the fully-reclined position.

SUMMARY OF THE INVENTION

The above-mentioned needs are met by the present invention which provides a reclinable ambulance cot used to load a patient into the back of an ambulance. The cot of the present invention is movable between a fully-reclined position, wherein a patient situated thereon is in a generally supine position, and a chair position, wherein the patient situated thereon is generally upright in a seated position thereby providing a cot with a reduced footprint.

Additionally, the cot of the present invention includes a folding undercarriage pivotally mounting a support frame to a roller base. A segmented bed frame is adjustably connected to the support frame and includes a back segment, a leg segment, and seat segment. Included to back segment is a spacing bracket pivotably connected at one end thereof to the undercarriage and pivotably connected at another end thereof to the support frame. The leg segment is pivotably connected to the support frame, and provides a raisable footrest panel and a raisable footrest that may be used additionally as a pull handle. The seat segment is connected to the back segment and includes a linkage assembly that is connected to the leg segment. Accordingly, with the bed frame segments interconnected as such, moving the cot from the chair position to the fully-reclined position effect's vertical lifting of the back segment, thereby elevating a wheeled free loading end thereof to a height sufficient to facilitate loading the fully-reclined cot into the back of an ambulance, and more particularly, into the back of an ambulance having a high transport deck.

Furthermore, the back segment of the cot of the present invention includes an inclinable backrest frame that is pivotably connected at one end thereof to the support frame. The inclinable backrest frame is connected at another end thereof to a cross member spanning the width of the cot by a lockable extending member, preferably a gas spring. A second lockable extending member, also preferably a gas spring, is mounted within the linkage assembly of the seat segment. Accordingly, with these lockable extending members assisting in the transition of the cot between the chair position and the full-reclined position jarring of the cot is prevented. Moreover, these lockable extending members permit the cot of the present invention to be secured into an infinite number of positions between the chair position and the fully-reclined position thereby adding further to the comfort of the patient.

In one aspect, the present invention is a reclinable ambulance cot comprising a three-sided rectangular support frame, a roller base, and four legs pivotally mounted to the support frame and the roller base such that the legs may swing the roller base generally parallel to the support frame. Additionally, a pair of diagonal braces is pivotally mounted to the support frame and the roller base to releasably secure the legs perpendicular to the support frame. An articulated bed frame having a wheeled back segment is pivotally mounted to the support frame for movement at least between a chair position and a fully-reclined position in which the wheeled back segment is elevated to a sufficient height to permit rolling of the reclined cot into the back of an ambulance with a high transport deck.

In another aspect, the present invention is a reclinable cot comprising a three-sided rectangular support frame, a roller base, and four downwardly extending legs each having upper and lower ends. The lower ends of the legs are pivotally mounted to the four corners of the roller base and the upper ends of the legs are pivotally mounted to the support frame such that the legs may swing generally parallel to the support. Additionally provided is a pair of diagonal braces to normally brace the legs perpendicular to the support frame. The braces each having upper and lower links connected by an over-center hinge in which the lower links are pivotally mounted to the roller base and the upper links are pivotally mounted to the support frame, and an articulated bed frame constituted by a leg segment, a seat segment, and a wheeled back segment linked to each other. The bed frame is pivotally mounted to the support frame for movement between a chair position, in which the seat segment is horizontal and the leg and the wheeled back segments are generally vertical, and a fully-reclined position, in which all panels are inclined. In the fully-reclined position the wheeled back segment is elevated to a sufficient height to permit rolling of the reclined cot into the back of an ambulance with a high transport deck.

These and additional objects, features and advantages of the present invention will become apparent to those reasonably skilled in the art from the description which follows, and may be realized by means of the instrumentalities and combinations particularly pointed out in the claims appended hereto.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the present invention will be had upon reference to the following description in conjunction with the accompanying drawings in which like reference numerals represent like parts, and wherein:

FIG. 1

is a side view of a reclinable ambulance cot according to a preferred embodiment of the present invention, showing the cot in a chair position;

FIG. 2

is a side view of the reclinable ambulance cot of

FIG. 1

, showing the cot in a fully-reclined position; and,

FIG. 3

is a rear view of the reclinable ambulance cot of

FIG. 1

, showing the cot in a chair position.

DETAILED DESCRIPTION OF THE INVENTION

With reference to

FIGS. 1-3

, according to an embodiment of the present invention a reclinable ambulance cot

10

is shown. Preferably, both sides of the cot

10

are identical, and as such with reference to

FIGS. 1 and 2

, only one side of the cot

10

will be described herein. The reclinable ambulance cot

10

includes a collapsible undercarriage, generally indicated by

20

, supportably connecting a roller base

30

to a support frame

40

. Roller base

30

includes a generally rectangular frame having members

32

, connected in an end-to-end fashion, and conventional wheels

34

rotatably mounted within brackets

34

a

,

34

b

to frame members

32

at their respective ends of intersection. Preferably, the front brackets

34

a

are rotatably mounted to frame members

32

to facilitate steering and maneuvering of cot

10

, whereas the rear brackets

34

b

are fixedly mounted to frame members

32

.

The support frame

40

is rectangular in shape with three sides having frame members and a fourth side open to permit patient loading. The support frame

40

is generally comprising a pair of base members

42

, and cross member

55

(FIG.

3

). Each of the pair of base members

42

may include a side shield

43

fixedly secured, such as, for example, by bolts, and an upright member

44

pivotably connected by fixed pin

45

a

and by locking pin

45

b

. It is to be appreciated that locking pin

45

b

is coaxial with fixed pin

45

a

. Upright member

44

pivots about the common axis of fixed pin

45

a

and locking pin

45

b

to move between an upward position, such as is shown in the

FIGS. 1 and 2

, wherein upright member

42

is generally coplanar with and extends upwardly from side shield

43

, and a downward position as indicated by the dashed line in

FIG. 2

, wherein upright member

44

is positioned over side shield

43

. Locking pin

45

b

is any conventional locking mechanism that is adapted to lock upright member

44

in either the upward position or the downward position. Alternatively, locking pin

45

b

may be adapted to lock upright member

44

in any angularly-offset position between the upward position and the downward position. Cross-member

55

is fixedly secured between a pair of side rail

53

, and is offset therefrom by a preselected distance, such as, by brackets

56

.

Undercarriage

20

includes two pairs of fixed-length legs

22

,

57

pivotally mounted to the support frame

40

and the roller base

30

such that the legs

22

,

57

may swing the roller base

30

generally parallel to the support frame. The first pair of fixed-length legs

22

pivotably connects a front end of roller base

30

to base member

42

. The second pair of fixed-length legs

57

pivotably connect a rear end of roller base

30

, preferably rear roller base member

32

a

, to cross-member

55

. A pair of braces

24

is pivotally mounted diagonally to the support frame

40

and the roller base

30

. The pair of braces

24

releasably secures the legs

22

,

57

perpendicularly to the support frame

40

. The pair of diagonal braces

24

normally brace the legs

22

,

57

perpendicularly to the support frame

40

, in which the braces

24

each have both upper and lower links

23

a

and

23

b

, respectively, connected by an over-center hinge

21

. Since each lower link

23

b

is pivotally mounted to the roller base

30

and each upper link

23

a

is pivotally mounted to the support frame

40

, breaking the over-center hinge

21

will permit the support frame to collapse along with roller base

30

into a retracted, compact orientation. A hand-operated level

97

is operatively connected to a conventional breaking mechanism (not shown) to facilitate the breaking or releasing of the braces

24

thereby permitting the roller base

30

to swing parallel to the support frame

40

. One such conventional breaking mechanism is disclosed by U.S. Pat. No. 3,289,219 to Ferneau et al., which is herein incorporated by reference.

Cot

10

further includes an articulated bed frame, generally indicated by

50

, which is adjustable between a chair position, such as shown in

FIG. 1

, and a fully-reclined position, such as shown in FIG.

2

. Bed frame

50

comprises three main segments namely, a wheeled back segment

52

, a leg segment

62

and a seat segment

72

operably connected to each other between the pair of base members

42

. Back segment

52

includes the pair of side rails

53

which are pivotably connected to rear ends of the pair of base members

42

, such as at first pivot point

91

. As such, with the wheeled back segment

52

, the seat segment

72

, and the leg segment

62

operably connected to each other in this fashion, when the cot is in the chair position, the seat segment

72

is generally horizontal and both the leg segment

62

and the wheeled back segment

52

are generally vertical relative to the base

30

. A wheel

81

is affixed to a free end

53

a

of each side rail

53

, defining a loading end of the cot

10

thereof. The wheels

81

may be rotatably connected to one another, such as by axle

82

as shown in FIG.

3

.

Back segment

52

further includes a frame-like backrest member

54

that is connected at a hinged end

54

b

(

FIG. 3

) thereof between the pair of side rails

53

, such as at second pivot point

92

. A first extending member or biasing spring

83

is connected at a first end to backrest member

54

adjacent a free end

54

a

thereof, and is connected at a second end to cross-member

55

. Biasing spring

83

provides a positive, tensile biasing force when activated. For example, biasing spring

83

is preferably a gas spring having a lockable valve therein, such as the locking gas springs sold under the trademark BLOC-O-LIFT by Stabilus of Gastonia, N.C. Preferably, biasing spring

83

is a model 2482MM-C0275N 135/99 BLOC-O-LIFT brand gas spring manufactured by Stabilus providing a 275-newton tensile biasing force when the locking mechanism thereof has been released. Lock release

84

is connected to backrest member

54

such that, depressing release

84

releases the locking mechanism within biasing spring

83

, thereby causing backrest member

54

to pivot about second pivot point

92

into an upright position shown with dashed line in

FIG. 2

or any position therebetween shown by the arrow in

FIG. 2

under the influence of the biasing force of spring

83

. Once release

84

is released, the locking mechanism within biasing spring

83

prevents further extension thereof, thereby locking backrest member

54

in the upright position or any of an infinite number of positions therebetween. Moving backrest member

54

to the flat position as shown in

FIG. 1

is accomplished by depressing release

84

and exerting a counter force against the biasing force of the biasing spring

83

. Once the backrest member

54

is back in the flat position, releasing release

84

will lock the backrest panel in the flat position.

Leg segment

62

includes a pair of side members

63

, and each connected at an upper end thereof to front ends of the pair of the base members

42

, such as at third pivot points

93

. A foot support panel

64

is positioned between the pair of side members

63

, near respective lower ends thereof, and is pivotably connected thereto, such as at fourth pivot points

94

. A secondary retractable footrest

61

pivotally mounted to the pair of side members

63

is also provided which can be elevated and secured in place by a pair of locking arms

67

, illustrated in

FIG. 2

, to provide a footrest to a reclined patient and to act as a pull handle. The footrest

61

is stowed flush against the side members

63

as illustrated in FIG.

1

.

Seat segment

72

is positioned between the pair of base members

42

and is pivotably connected at a rear end thereof to the hinged end

54

b

of backrest member

54

, such as at second pivot points

92

. A front end of the seat segment

72

is connected to a rear end of the foot support panel

64

of the leg segment

62

by a leg support panel

65

, which is pivotably connected at a first end thereof to the seat segment

72

, such as at fifth pivot point

95

, and which is pivotably connected at a second end thereof to the rear end of the foot support panel

64

, such as at sixth pivot point

96

.

Each one of a pair of linkage brackets

74

is fixedly secured to its respective side member

63

of leg segment

62

and is connected to one of the pair of side rails

53

of back segment

52

by a respective linkage bar

76

. More particularly, a first end of each linkage bar

76

is pivotably connected to its respective linkage bracket

74

and a second end of each linkage bar

76

is pivotably connected to its respective side rail

53

. Accordingly, a four-bar linkage system is defined consisting of linkage bars

76

, side members

63

, base members

42

and side rails

53

, having pivotably, pinned connections with one degree of relative movement between adjacent links.

Linkage bars

76

connect back segment

52

with leg segment

62

such that as back segment

52

is pivoted about first pivot point

92

in the direction shown generally as moment arrow “M” (FIG.

1

), foot support panel

64

, leg support panel

65

, seat segment

72

and backrest member

54

move into a generally planar alignment or inclined, fully-reclined position as shown particularly in

FIG. 2

, such that a patient situated thereon assumes a generally supine position. It is to be appreciated that during this movement the brackets

56

pivot about cross- member

55

above legs

57

thereby effecting a vertical lifting of side rails

53

. This vertical lifting of the side rails

53

above legs

57

raise the attached wheels

81

to an elevation sufficient to roll the loading end of the cot

10

onto a high transport deck, indicated by dashed line

99

in

FIG. 2

, of an ambulance. Accordingly, bracket

56

and legs

57

together extend wheels

81

at least 30 inches and more preferably, 33 inches above a loading surface

100

.

Two lockable extending members or lift biasing springs

85

are each pivotably connected to, and thereby connect, one of the pair of linkage bars

76

with one of the pair of side rails

53

. The pair of lift biasing springs

85

is constructed in a similar fashion as biasing spring

83

described above. It is to be appreciated that using the pair of lift biasing springs

85

reduces weight and part count while improving ergonomics and function. The use of lift biasing springs

85

allow infinite adjustment and part reduction over the prior art six-position ratchet bar style locking and positioning mechanisms, such as provided in U.S. Pat. No. 3,289,219 to Ferneau et al. Preferably, the pair of lift biasing springs

85

are model 6465KM0400N 103/98 gas springs manufactured by Stabilus under the trademark BLOC-O-LIFT, and provide up to 400 newtons of tensile biasing force when a locking mechanism provided therein is released. Release arm

84

a

is operatively connected to and activates release mechanisms within lift biasing springs

85

, as described hereinabove with respect to springs

83

. Lift biasing springs

85

assist relative movement of linkage bars

76

relative to side rails

53

to increase the angle therebetween, thereby smoothly urging the bed frame

50

from the chair position shown in

FIG. 1

to the fully-reclined position shown in

FIG. 2

or to any other infinite number of positions therebetween without jarring the patient carried thereon.

Backrest member

54

includes a substantially planar backrest panel

58

for supporting the patient situated thereon and a second cross-member

59

to support the backrest panel

58

. Provided through panel

58

are one or more slotted, openings

58

a

near the cross-member

59

, such that a restraining strap (not shown) used to restrain the patient against the cot

10

can pass through the opening

58

a

, front-to-back, and tied around the cross-member

59

. As such, cross-member

59

is preferably spaced away from panel

58

. Additionally, pillows, pads or cushions may be secured to foot support panel

64

, foot support panel

65

, seat segment

72

and backrest member

54

, and any combination thereof, to provide a comfortable resting place upon which the patient is situated.

Although the present invention has been described in terms of a specific embodiment which is set forth in detail, it should be understood that this is by illustration only and that the present invention is not necessarily limited thereto, since alternative embodiments not described in detail herein will become apparent to those skilled in the art in view of the above description, the attached drawings and the appended claims. Accordingly, modifications are contemplated which can be made without departing from either the spirit or the scope of the present invention.