Patent Publication Number: US-7581265-B1

Title: Roll-in chair cot with three cot height positions

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application No. 60/687,279, filed Jun. 3, 2005, which is incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to ambulance cots used to load patients into the back of an ambulance. More particularly, the present invention relates to a roll-in chair cot with three cot height positions. 
     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, 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 in either a fully elevated or a fully lowered cot height position to an ambulance parked near the patient&#39;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 lowered position for transportation to the hospital. 
     However, in removing the patient from his home, it is sometimes difficult for paramedics to place the patient on the cot situated in either the fully lowered or the fully elevated cot height position, such as is typical for prior art cots. Additionally, it is often difficult—sometimes impossible—for paramedics to traverse stairs, and narrow hallways and doorways, with the cot in either the fully lowered or the fully elevated cot height position. 
     SUMMARY OF THE INVENTION 
     It is against the above background that the present invention provides a number of advancements and improvement over the prior art. 
     In one embodiment, a roll-in chair cot for transporting a patient is provided. The roll-in cot comprises a patient support surface configured to be movable between a chair position, a fully lowered position, a fully elevated cot height position, and an intermediate cot height position between the fully lowered cot height position and the fully elevated cot height position. The patient support in each of the fully lowered cot height position, a fully elevated cot height position, and an intermediate cot height position is configured to permit the patient to be transported thereon in a generally supine position. 
     In another embodiment, a roll-in chair cot for transporting a patient is provided. The roll-in cot comprises a patient support surface configured to be movable between a chair position, a fully lowered cot height position, a fully elevated cot height position, and an intermediate cot height position between the fully lowered cot height position and the fully elevated cot height position. The chair position provides the patient support in a manner to permit the patient to be transported upon the chair cot in a generally seated position, and each of the cot height positions provides the patient support in a manner to at least permit the patient to be transported upon the chair cot in a generally supine position. The cot transitions from the fully elevated cot height position to the intermediate cot height position in a first direction, and from the fully elevated cot height position to the fully lowered position in a second direction opposite to the first direction. 
     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: 
         FIGS. 1A and 1B  are perspective views of a roll-in chair cot according to an embodiment of the present invention, showing the cot in a cot configuration located at a fully raised cot height position; 
         FIG. 2  is a side perspective view of one embodiment of a roll-in chair cot, with parts removed, to show the undercarriage thereof situated in the fully raised cot height position; 
         FIG. 3A  is a side perspective view of one embodiment of a roll-in chair cot situated in a fully lowered cot height position; 
         FIG. 3B  is a side perspective view of the roll-in chair cot of  FIG. 3A , with parts removed, to show the undercarriage thereof situated in a fully lowered cot height position; 
         FIGS. 4A and 4B  are perspective views of a roll-in chair cot according to an embodiment of the present invention, showing the cot in a cot configuration located at an intermediate cot height position; 
         FIGS. 5A and 5B  are side perspective views of one embodiment of a roll-in chair cot situated in an intermediate cot height position; 
         FIG. 5C  is a side perspective view of the roll-in chair cot of  FIG. 5A , with parts removed, to show the undercarriage thereof situated in an intermediate cot height position; 
         FIG. 6  is a close-up perspective view of a roll-in chair cot according to an embodiment of the present invention, showing the cot in a cot configuration located between the fully raised cot height position and an intermediate cot height position; 
         FIG. 7  is a perspective view of a roll-in chair cot according to an embodiment of the present invention, showing the cot in a cot configuration located at a fully raised cot height position; and 
         FIGS. 8A ,  8 B, and  8 C are perspective views of a roll-in chair cot according to an embodiment of the present invention, showing the cot in a chair configuration. 
         FIG. 9  is a close-up diagrammatic view of one embodiment of a locking pin assembly of an embodiment of a roll-in chair cot according to the present invention. 
         FIG. 10  is a diagrammatic view of another embodiment, with parts not illustrated, of a roll-in chair cot according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to  FIGS. 1A and 1B , a roll-in chair cot  10  according to an embodiment of the present invention is shown. Both sides of the cot  10  are identical, and as such with reference made first to  FIG. 1A , only one side of the cot  10  will be described herein. The roll-in chair 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 ,  32 A rotatably mounting castor wheels  34  at their respective ends. Each member pair  32 ,  32 A slidably move or telescope relative to each other. 
     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 telescoping members  42  and cross members  44 . Each of the pair of telescoping members  42  include a swing-down side hand rail  46  which are pivotably connected thereto. Each side hand rail  46  is moveable between an upward position, such as is shown in  FIG. 1A , a downward position, and a horizontal position. A locking mechanism  45 , best shown in  FIG. 4A , is adapted to releasably lock its respective side hand rail  46  in one of the above mentioned positions. 
     Undercarriage  20  includes a first pair of fixed length legs  22  which are pivotally mounted to the support frame  40  and the roller base  30  such that the first pair of legs  22  may swing the roller base  30  generally parallel to the support frame  40 . In particular, the first pair of fixed length legs  22  pivotably connect a front end of roller base  30  to a front telescoping end  24  of telescoping member  42 , which is best shown in  FIG. 2 . A second pair of fixed length legs  26  is pivotably connected at a rear end of roller base  30  at one end and pivotable and slidably connect at the other opposed end to telescoping member  42 . An optional combination bump guard and ground rolling wheel assembly  100  may be provided to each fixed length legs  26  as depicted in  FIGS. 1B and 3A . 
     A pair of diagonally extending braces  28  is pivotally mounted to the support frame  40  and the roller base  30 , in one embodiment as shown by  FIGS. 1A and 1B , and in another embodiment as shown by  FIG. 2 , to a lower end of the second pair of fixed length legs  26  above its pivot connect to the roller base  30 . The pair of diagonally extending braces  28  releasably support the legs  22  and  26  perpendicular to the roller base  30  and support frame  40  when the cot is positioned in the fully raised cot height position as illustrated in  FIGS. 1A and 1B . 
     As best shown by  FIG. 2 , each one of the pair of diagonally extending braces  28  have upper and lower links  23   a  and  23   b , respectively, connected by a center hinge  21 . Since each lower link  23   b  is pivotally mounted to either the roller base  30  or a respective one of the second pair of fixed length legs  26 , and each upper link  23   a  is pivotally mounted to the support frame  40 , breaking the center hinge  21  will permit the support frame  40  to collapse along with roller base  30  into a fully retracted cot height position which is best illustrated by  FIG. 3A . In the fully retracted cot height or lowered position, the roller base  30 , the wheel assembly  100 , and loading wheels  106  support the cot  10  on the ground.  FIG. 3B  is a side perspective view of the roll-in chair cot of  FIG. 3A , with parts removed, to show the undercarriage thereof situated in a fully lowered cot height position. 
     A conventional breaking mechanism (not shown) is used to facilitate the breaking or releasing of the braces  24  thereby permitting the roller base  30  to swing parallel to the support frame  40  into the fully retracted cot height position. One such conventional breaking mechanism is disclosed by commonly owned U.S. Pat. No. 3,289,219 to Ferneau et al., which is herein incorporated fully by reference. 
     It is to be appreciated that the cot  10  is further positionable in an intermediate cot height position which locates the support frame  40  at approximately bed height such that a patient may be laterally transferred from the bed to the cot  10  in a generally supine position. This intermediate cot height position is best illustrated by  FIG. 4A , with some part removed for convenience of illustration, and  FIG. 4B  showing a preferred embodiment. 
     As best shown by  FIGS. 5B and 6 , a hand operated release mechanism  50  in one embodiment is operably connected to a pair of latches  52  each rotatably mounted to a respective one of the telescoping members  42 . Each latch  52  releasably holds a respective pin  52  provided on the second pair of fixed length legs  26 . Releasing the pins  54  from the latches  52  thereby permits the front telescoping end  24  of the telescoping members  42  to extend allowing the first pair of fixed length legs  22  to swing the support frame  40  parallel to the roller base  30  in the direction opposite from placing the cot  10  in the fully retracted cot height position. In another embodiment, the hand operated release mechanism is connected to an internal locking mechanism situated inside each telescoping members  42 , having a latching pin arrangement  108  illustrated by  FIG. 9 . As illustrated, the latching pin arrangement  108  includes a ball pin  110  biased to a seated position within a cavity  112  provided near the enclosed end of the front telescoping end  24  to the telescoping member  42 . Upon operating an actuator, a ramp portion  114  of a latch  116  will ride under the ball portion of the ball pin to unseat it from the cavity, thereby permitting the telescoping end  24  to freely slide within telescoping member  42 . It is to be appreciated that the latch  116  is also biased to the locking position illustrated. 
     As the support frame  40  swings relative to the roller base  30 , the telescoping member  42  will come to rest on a shoulder portion  102  of the second pair of fixed length legs  26  thereby placing the cot  10  in the intermediate position, which is best shown by  FIGS. 5A and 5C . A landing brace  104  automatically folds down from a stowed position illustrated by  FIG. 3A  to a deployed position as shown in  FIG. 5A . The landing brace  104  provides additional stability to the cot when located in the intermediate position, such that the cot does not teeter. It is to be appreciated that transitioning the cot  10  in the opposite direction from the intermediate cot height position, will rotate the legs  22 ,  26  and cross braces  28  until the latch  52  once again releasably holds the pins  54 , thereby securing the cot  10  once again in the fully extended cot height position illustrated by  FIG. 1 . The latch  52  and pin  54  is best shown in  FIG. 6 . 
     Cot  10  further includes an articulated bed frame, generally indicated by  60 , which is adjustable between a cot configuration, such as shown in  FIG. 7  with the cot in the fully elevated position, and a chair configuration, such as shown in  FIGS. 8A ,  8 B, and  8 C. Bed frame  60  comprises three main segments namely, a wheeled back segment  62 , a leg segment  64  and a seat segment  66  operably connected to each other between the pair of telescoping members  42 . Back segment  62  is pivotably connected to one of the cross members  44 . As such, with the back segment  62 , the leg segment  64 , seat segment  66  operably connected to each other in this fashion, when the cot  10  is in the chair position, the seat segment  66  is generally horizontal and both the back segment  62  and the leg segment  64  are generally vertical relative to the base  30  as illustrated by  FIG. 8A . The pair of loading wheels  106  are affixed to a free end of the support frame  40 , best shown by  FIG. 8C , thereby defining a loading end of the cot  10  thereof. The front loading wheels  106  may be adjusted to allow for additional height as explained hereafter. 
     It is to be appreciated that in another embodiment, such as illustrated by  FIG. 10 , the fixed length legs  26  may be releasably mounted to the wheeled base  30  via bracket  118  having a bolting pattern  120 . The bolting pattern  120  permits the height H of the loading wheels  106  to be adjustable. In one embodiment, the bolting pattern  120  permits adjusting the loading wheels  106  between a height H ranging from about 24″ to about 34″. It is to be appreciated that member pairs  32 ,  32 A telescope when the cot is transitioned from a lower position to an elevated loading position as depicted in  FIG. 10 , such that the center of gravity between the points of contact is kept on the ground such that the cot  10  does not tip. 
     Referring back to  FIG. 8A , the back segment  62  further includes a frame like backrest member  70  that is pivotably mounted between the frame of the back segment  62  to one of the cross members  44 . A first extending member or biasing spring  72  ( FIG. 1A ) is connected at a first end to backrest member  70  adjacent a free end thereof, and at a second end to a cross member  74 . Biasing spring  72  provides a positive, tensile biasing force when activated. Lock release  84  is connected to backrest member  70  such that, depressing release  84  releases the locking mechanism within biasing spring  72 , thereby causing backrest member to pivot about the respective cross member  44  into an upright position from 0° to 90° or any position therebetween, such as illustrated by  FIG. 7 , under the influence of the biasing force of the spring. 
     As illustrated by  FIGS. 8A ,  8 B, and  8 C, the leg segment  64  connects at an upper end thereof to front ends of the pair of the telescoping members  42 . A foot support panel  76  is pivotably connected to the leg segment  64 . The foot support panel  76  may be elevated to provide a footrest to a reclined patient. In the cot position, the foot support panel  76  is normally stowed such as illustrated in  FIG. 7 . As best shown by  FIG. 8B , the bed frame  60  may be situated in the chair configuration of  FIG. 8A , a cot configuration of  FIG. 1B , and a number of reclined positions therebetween. In one embodiment, transitioning the back segment  62  from the chair position to a reclined position, will also transition the leg segment  64  to the associated reclined position due to these segments being linked by push arm  83 . 
     Seat segment  66  is positioned between the pair of telescoping members  42  and is pivotably connected at a rear end thereof. A front end of the seat segment  66  is connected to a rear end of the foot support panel  76  of the leg segment  62  by a leg support panel  65 , which is pivotably connected at a first end thereof to the seat segment  66  and which is pivotably connected at a second end thereof to the rear end of the foot support panel  76 . 
     In one embodiment, a pair of lift biasing springs  85  are each pivotably connected between the seat frame and the back frame. In other embodiment, a single lift biasing spring or cylinder may be used. The pair of lift biasing springs  85  is constructed in a similar fashion as biasing spring  84  described above. It is to be appreciated that using the pair of lift biasing springs  85  reduces weight and allow infinite adjustment between the leg, seat, and back frames of the cot  10  to the chair configuration of  FIG. 8A , a cot configuration of  FIG. 1B , and a number of reclined positions therebetween, which allows a patient to find a chair angle that provides the most comfortable position. 
     Pillows, pads or cushions or a full length mattress as shown in  FIGS. 7 and 8  may be secured to support frame  40  to provide a comfortable resting place upon which the patient is situated. Additionally, the cot may be provided with a number of restraints as is customary in the art. 
     As described above, the roll-in chair cot of the present invention is movable between three cot height positions: a fully lowered position, a fully elevated position, and an intermediate position locating the cot at approximately bed height such that a patient may be laterally transferred from the bed to the cot in a generally supine position. Additionally, the roll-in chair cot readily converts from a level cot to a contoured chair for maneuvering ease in narrow hallways, elevators, and other confined spaces. The roll-in cot has folding legs for simple loading and unloading by two emergency medical technicians (EMTs) into the back of an emergency vehicle. Spring-actuated, folding legs minimize the lifting effort required by the EMTs. Additionally, the supporting legs automatically lock into place when the undercarriage is fully unfolded. In one embodiment, rectangular, tubular aluminum construction provides durability and strength. In another embodiment, plastic bearings are provided on rotating components for easy movement. In still other embodiment, the wheels are greaseless wheels. In another embodiment, the cot provides an adjustable backrest angle from 0° to 75° which allows a patient to be placed in a comfortable position during transport. Patient restraint system ensures safety of patient during transport, and in one embodiment comprises two across patient restraints and one shoulder harness. In another embodiment, a full-length, sectional mattress provides comfort and folds with the cot as it is moved into the chair position. Swing-down side hand rails enable convenient patient transfer from hospital bed to cot. 
     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.