1. Field of the Invention
This invention relates to ambulances, and in particular to an ambulance shock-absorbing platform for stretcher.
2. Background of the Invention
Ambulances are commonly used to transport sick or injured patients from a site of injury, residence or work location to a hospital, clinic or other location where treatment may be provided. Perhaps a patient will be transported by ambulance to an airport where the patient will be transported by air to another location.
A patient is typically placed on a stretcher, and the stretcher is then rolled onto the ambulance floor. Stretchers are usually equipped with hard rubber or plastic wheels, so there is generally no shock absorption function between the stretcher and the ambulance floor.
A common complaint made by patients being transported by ambulance is that the ride is rough and bumpy. The rough and/or bumpy ride patients may experience while reposed on a stretcher in the back of an ambulance can actually be a health and/or safety hazard. For example, where a patient having a cervical spinal fracture is being transported, a rough ambulance ride could actually make the injury worse.
Accordingly, it would be desirable to provide a shock-absorbing platform on the ambulance floor upon which to place a stretcher. In this arrangement, the shock-absorbing platform would provide a smoother, less bumpy ride, to the patient traveling on the stretcher. An ambulance shock-absorbing platform for stretcher could also reduce the chances of further injury to the patient caused by a rough and/or bumpy ambulance ride.
A number of approaches have been taught over the years to address this problem. U.S. Pat. Nos. 7,621,705, 6,890,137, 5,016,862, 2,324,685 and 42,152 were granted to Hillberry et al (first two references), Leyshon, Ekman et al., and Arnold respectively. These devices taught shock absorption by means of mechanical springs. Typically, these designs required modification of the ambulance floor itself, and/or complex mechanical arrangements with multiple linkages in the case of Leyshon '862. Such ambulance modification and complexity could lead to increased cost in these designs. In addition, no provision was made to increase shock absorption function by inflating one or more gas actuators.
U.S. Pat. No. 6,527,263 was granted Verbrugge for a shock-absorbing apparatus which featured mechanical linkages actuated by an air actuator. While this design provided shock-absorption, it was complex, and hence costly.
A number of patents have been issued for shock-absorption capability built into the stretchers themselves. Representative of this approach are U.S. Pat. Nos. 7,124,454, 7,111,340, and 6,942,226 granted to Walkingshaw, Mitchell et al., and Walkingshaw respectively. These designs typically included some type of shock absorption capability built into the stretcher itself. While these patents taught apparatus which provided shock-absorption, the necessity of additional structure and hence increased cost both constituted disadvantages to this way of approaching the problem. In addition, replacement of existing conventional stretchers with shock-absorbing stretchers was required. Where an institution used a mix of conventional stretchers and shock-absorbing stretchers, only the latter's passengers would benefit from the smoother ride provided by the shock-absorbing stretchers.
Still another approach was taught by U.S. Pat. No. 5,135,350 granted Eelman et al. This design provided a wheeled adjustable-height platform with shock-absorptive function as the platform is lowered. A stretcher would be placed atop the platform, and the platform would then be raised to the level of an ambulance floor. The stretcher could then be rolled off the platform and onto the ambulance floor. While this design provided shock absorption to a stretcher on the platform when the platform was lowered, no shock absorption was provided the stretcher once the stretcher was located within the ambulance.
EMS Emergency Mobile Systems published a flyer regarding their Shock Absorbing Hydraulic stretcher Platform EP SA 030. While this system tilted to allow a stretcher to be rolled up-hill onto its platform, no gas shock absorption was taught. Rather, the system was described as hydraulic. Hydraulic fluid is incompressible, and thus makes a poor shock-absorption medium.
Accordingly, it would be desirable to provide a gas shock-absorbing platform which can be quickly and easily mounted to the floor of an existing ambulance, upon which a conventional stretcher may be positioned and immobilized in conventional fashion. Following installation of the stretcher on the platform, it would be beneficial to provide means to inflate a plurality of gas actuators to raise the platform sufficiently to provide shock absorption to the stretcher mounted on the platform, and at the end of the ride, deflation of the gas actuators would lower the platform for egress of the stretcher. The ability to recess the gas actuators in the floor of the ambulance would also be desirable, in an alternate embodiment.
Accordingly, it is an object of the present invention to provide an ambulance shock-absorbing platform for stretcher which cushions a stretcher mounted on the platform. Design features allowing this object to be accomplished include a stage supported by a plurality of gas actuators which may be inflated by a pump driven by a prime mover. Advantages associated with the accomplishment of this object include increased patient safety and comfort.
It is another object of the present invention to provide an ambulance shock-absorbing platform for stretcher whose stage may be raised for increased shock absorption, and lowered to move a stretcher onto and off of the stage. Design features allowing this object to be accomplished include a stage supported by a plurality of gas actuators which may be inflated by a pump driven by a prime mover, and a valve which may be opened to reduce gas pressure within the gas actuators. Benefits associated with the accomplishment of this object include increased ease of installing a stretcher on the stage and removing the stretcher from the stage.
It is still another object of this invention to provide an ambulance shock-absorbing platform for stretcher which is quickly and easily installed on an existing ambulance bed. Design features enabling the accomplishment of this object include a plurality of gas actuators having tabs, quick-release fasteners, or other means to attach the gas actuators to an existing ambulance floor. Advantages associated with the realization of this object include reduced work, time and cost in installing the instant ambulance shock-absorbing platform for stretcher to into an existing ambulance.
It is another object of the present invention to provide an ambulance shock-absorbing platform for stretcher which is useable with conventional stretchers. Design features allowing this object to be accomplished include a stage supported by a plurality of gas actuators which may be inflated by a pump driven by a prime mover, an M bar on the platform, and hook slidably attached to a hook support on the platform. Benefits associated with the accomplishment of this object include the ability to use existing stretchers with the instant ambulance shock-absorbing platform for stretcher, along with the associated cost savings of not having to purchase new stretchers.
It is yet another object of this invention to provide an ambulance shock-absorbing platform for stretcher which is inexpensive to produce. Design features allowing this object to be achieved include simplicity of design and the use of components made of readily available materials. Benefits associated with reaching this objective include reduced cost, and hence increased availability.
The invention, together with the other objects, features, aspects and advantages thereof will be more clearly understood from the following in conjunction with the accompanying drawings.
Seven sheets of drawings are provided. Sheet one contains
The instant ambulance shock-absorbing platform for stretcher 20 comprises stage 22 upon which stretcher 10 may be removably installed.
Referring now to these figures, stage 22 is generally flat and horizontal, and sized to co-extend at least with a conventional stretcher 10 when viewed in plan view, from above. Stage 22 comprises a conventional M bar 24 at one end, and a conventional hook 28 reciprocating within a hook support 26. In the instant ambulance shock-absorbing platform for stretcher 20, M bar 24 and hook support 26 are mounted to stage 22, so as to provide the function of immobilizing stretcher 10 on stage 22 while stage 22 elevates and descends as depicted in
M bar 24 comprises two M bar recesses 25, each sized and positioned to admit a stretcher front leg 12. Hook 28 reciprocates within hook support 26 as indicated by arrow 32 in
The stretcher immobilization system employing M bar 24 having M bar recesses 25, stretcher locking peg 14, and hook 28 is commonly used in existing ambulances 2. In a conventional ambulance, M bar 24 would be installed on ambulance floor 4, and hook 28 would be installed on an ambulance wall.
As depicted in
Also as depicted in
Stretcher 10 may be removed from its position atop stage 22 by reversing the above steps: first hook 28 is slid into its open position opposite arrow 34 in
Shock absorption between stage 22 and ambulance floor 4 is provided by gas actuators 40, as depicted in
Gas actuator 40 may be a gas bladder made of elastic material such as rubber, a bellows, a diaphragm, a piston in cylinder arrangement, or any other appropriate gas actuator. While the figures illustrate gas actuator 40 as an elastic bladder, it is intended to fall within the scope of this disclosure that gas actuator 40 be any appropriate type of gas actuator.
Where gas actuator 40 is an elastic bladder made of elastic material such as rubber, due to the elastic nature of the material from which gas actuator 40 is made, when inflated, the height of gas actuator 40 increases. Conversely, when deflated, the height of gas actuator 40 decreases. Thus, when stage 22 is installed on a plurality of gas actuators 40, when these are inflated stage 22 ascends; when deflated, stage 22 descends.
Gas actuator 40 may optionally incorporate any of a number of attachment means to attach gas actuator 40 to ambulance floor 4 and stage 22. Such attachment may be accomplished by any of a number of attachment means well-known in the art, such as threaded connectors, quick disconnects, adhesive, hook-and-look material, etc. For example, gas actuator 40 may optionally incorporate a number of tabs 42 to attach gas actuator 40 to ambulance floor 4 and stage 22 using threaded connectors, quick-disconnects, etc.
The instant ambulance shock-absorbing platform for stretcher 20 also comprises valve 48 connected to gas actuators 40 by lines 46. When valve 48 is opened, gas actuators 40 are vented to atmosphere and deflate, thus decreasing their height and that of platform 22. Thus, the height of platform 22 is increased by closing valve 48 and turning on pump 52. Conversely, the height of platform 22 is decreased by turning off pump 52 and opening valve 48.
In the representative example illustrated, wherein prime mover 50 is an electric motor, the means to stop the operation of prime mover 50 when stage 22 reaches its end-of-travel upper position is upper end-of-travel limit switch 54, and the means to close valve 48 when stage 22 reaches its end-of-travel lower position is lower end-of-travel limit switch 56.
The electrical system depicted in
As may be observed in
The operation of the instant ambulance shock-absorbing platform for stretcher 20 depicted in
As depicted in
As depicted in
The schematic depicted in
In the preferred embodiment, stage 22 was made of metal, synthetic, or any other appropriate material. Gas actuators 40 were bladders, bellows, diaphragms, piston in cylinder, or any other appropriate gas actuator. Where gas actuators 40 bladders, they were made of elastic material such as rubber, or any other appropriate elastic material. Prime mover 50, pump 52, valve 48, upper end-of-travel switch 54 and lower end-of-travel limit switch 56 were commercially available components. Valve 48 was an electrically-actuated valve, or any other appropriate valve. M bar 24, hook 28 and hook support 26 were made of metal, synthetic, or any other appropriate material.
While a preferred embodiment of the invention has been illustrated herein, it is to be understood that changes and variations may be made by those skilled in the art without departing from the spirit of the appending claims.