Ambulance cot and hydraulic elevating mechanism therefor

1. An ambulance cot, comprising:

a base frame;

a litter frame; and

an elevating mechanism interconnecting said base frame and said litter frame and being configured to effect changes in elevation of said litter frame relative to said base frame, said elevating mechanism being configured to detect a presence and an absence of a force urging a change in elevation of said litter frame relative to said base frame to thereby cause said base frame and said litter frame to become oriented closer together.

2. An ambulance cot comprising:

a base frame and a litter frame;

a deployment mechanism interconnecting said base frame and said litter frame and being configured to effect changes in distance between said litter frame and said base frame, said deployment mechanism having a detection device configured to detect a presence and an absence of a force urging a change in distance between said litter frame and said base frame to cause said base frame and said litter frame to become oriented closer together; and

a control mechanism on said ambulance cot, said control mechanism including a manually operable device for controlling said deployment mechanism, said control mechanism being configured to effect a rapid movement of said deployment mechanism in response to said detection device detecting an absence of said force and in response to an operation of said manually operable device, whereby when said ambulance cot is lifted away from a support surface, causing said detection device to detect an absence of said force, and said manually operable device, is operated, said base frame will be rapidly drawn toward said litter frame by said deployment mechanism.

3. The ambulance cot according to claim 2 , wherein said deployment mechanism includes a hydraulic element and said detection device is further configured to detect a change in pressure of a hydraulic fluid in the hydraulic element.

4. The ambulance cot according to claim 2 in combination with an ambulance having a cargo area, the ambulance comprising a loading mechanism configured to couple to said ambulance cot and lift said ambulance cot away from the support surface, the movement of said base frame away from said support surface causing said detection device to detect the absence of said force.

5. An ambulance cot, comprising:

a base frame configured for support on a surface;

a litter frame configured for supporting thereon a patient;

an elevating mechanism interconnecting said base frame and said litter frame and being configured to interconnect said litter frame and said base frame in order to facilitate movement of said base frame and said litter frame toward and away from each other; and

a control mechanism on said cot configured to facilitate said movement of said base frame and said litter frame toward each other and at differing speeds predicated on at least one of whether said base frame is supported on said surface and said litter frame is supported by an external support separate from said elevating mechanism.

6. The ambulance cot according to claim 5 , wherein said control mechanism is configured such that when said base frame is supported on said surface, said control mechanism controls said elevating mechanism to move said litter frame toward said base frame at a preselected speed.

7. The ambulance cot according to claim 5 , wherein said control mechanism is configured such that when said litter frame is supported by the external support separate from said elevating mechanism, said control mechanism controls said elevating mechanism to move said base frame toward said litter frame at a pre-selected speed.

8. The ambulance cot according to claim 5 , wherein said control mechanism is configured such that when said base frame is supported on said surface, said control mechanism controls said elevating mechanism to move said litter frame toward said base frame at a first speed; and

wherein said control mechanism is additionally configured such that when said litter frame is supported by the external support separate from said elevating mechanism, said control mechanism controls said elevating mechanism to move said base frame toward said litter frame at a second speed.

9. The ambulance cot according to claim 8 , wherein said first and second speeds are each pre-selected and said second preselected speed is significantly different than said first pre-selected speed.

10. The ambulance cot according to claim 8 , wherein said second speed is greater than said first speed.

11. The ambulance cot according to claim 5 , wherein said litter frame has at least one preferred location whereat the external support is applied, said control mechanism includes at least one manually engageable member located on said litter frame adjacent said at least one preferred location.

12. The ambulance cot according to claim 11 , wherein said at least one manually engageable member is a manually operated switch.

13. The ambulance cot according to claim 11 , wherein hand grips configured to be manually engaged by an attendant are provided at said preferred locations.

14. The ambulance cot according to claim 5 , wherein the external support is provided by an attendant lifting up on said litter frame.

15. The ambulance cot according to claim 5 , in combination with an ambulance having a cargo area, the ambulance comprising a loading mechanism configured to couple to said ambulance cot and lift said ambulance cot and said base frame thereof away from the surfaces to thereby define said external support.