GB2459847A

GB2459847A - Stretcher with frame lock

Info

Publication number: GB2459847A
Application number: GB0808177A
Authority: GB
Inventors: Stephen Paul Jenkins; Shahid Saleem; David Whyman
Original assignee: Ferno UK Ltd
Current assignee: Ferno UK Ltd
Priority date: 2008-05-07
Filing date: 2008-05-07
Publication date: 2009-11-11
Anticipated expiration: 2028-05-07
Also published as: GB201007575D0; GB2459847B; GB2468604B; GB2468604A; GB0808177D0

Abstract

A lower frame 14 of a stretcher is secured to a forwards holder 90 and a rearwards clamp mechanism 100 mounted on an ambulance floor. The upper frame is held fast to the lower frame by plate locks 42 holding the upper frame 12 to the lower frame 14. A hydraulic actuator 16 holds the other ends of the stretcher down. The plate locks can be released and the hydraulic actuator can raise the upper frame when the lower frame fast from the ambulance floor. The stretcher may be wheeled and the locks may include a ratchet mechanism.

Description

STRETCHER

The present invention relates to a stretcher, a stretcher in combination with a stretcher securing arrangement and a method of operating a stretcher.

In EU 1 378 220 (the contents of which are hereby incorporated) there is described a stretcher and a retention mechanism on an ambulance floor. The stretcher includes an upper and a lower frame. When loading the stretcher into the ambulance the upper frame is in a lowered position. Wheels on the stretcher roll on the ambulance floor during loading and an upwardly and rearwardly projecting diverging spike guides the front of the stretcher in a sideways direction to ensure that the front is aligned. That spike also acts to engage with the upper frame to prevent the upper frame from being raised.

The upper frame, at the other end of the stretcher, engages a pair of clamps on the stretcher floor to directly hold the upper frame.

Such an arrangement securely holds the upper frame and helps prevent the upper frame leaving the floor of the ambulance should the ambulance be involved in a crash.

However, should the patient suffer a heart attack or require immediate treatment prior to arriving at a hospital it is difficult to perform emergency procedures.

With such a prior arrangement the clamps at the rear of the stretcher are disengaged and the upper frame is withdrawn from beneath the spike. The space within an ambulance is extremely restricted. When the stretcher is moved to be clear of the spike and clamps there is not sufficient room to work on the patient. Consequently the stretcher has to be removed from the ambulance before the upper frame can be raised and an emergency procedure performed.

It is an object of the present invention to attempt to overcome at least one of the above or other disadvantages.

The present invention is defined in the claims and

elsewhere in this specification.

The present invention can be carried into practice in various ways but one embodiment will now be described by way of example and with reference to the accompanying drawings, in which:-Figure 1 is a rear perspective view of a stretcher in a raised position; Figure 2 is a view corresponding to Figure 1 with the stretcher in a lowered position; Figure 3 is a rear perspective view of the stretcher in a raised position; Figure 4 is a side perspective view showing details of the front region of the forwards part of the stretcher; Figure 5 is a side view of a plate lock provided towards each side of an upper frame; Figure 6 is a front view of the lower frame of the stretcher; Figure 7 is a perspective view of a forward holder mounted on the floor of a vehicle such as an ambulance, and Figure 8 is a perspective view of a clamp mechanism arranged to hold a bar of the lower frame at the rear of the stretcher.

As shown in Figures 1 to 3 the stretcher 10 includes an upper frame 12 and a lower frame 14 both of substantially the same rectangular shape. The upper frame is movable relative to the lower frame from a raised position shown in Figures 1 and 3 and a lowered position shown in Figure 2.

An hydraulic actuator 16 powers the frames between the upper and lower positions and assists in holding the frames at the limit positions shown or any position between the limit positions.

The frames are connected by cross members 18 and 20 at each side. Towards the forward end of the stretcher the ends of the cross members 18 and 20 are each pivotally connected to the upper and lower frames 12 and 14.

Towards the rear of the stretcher the ends of the members 18 and 20 are pivotally and translationally movable relative to the frames. As shown in Figure 1, at the rear of the stretcher the lower ends of the cross members 20 are pivotally connected to a cross bar 22 which slides on rods 24. The rods 24 extend parallel to the sides 26 of the lower frame between cross braces 28 and 30. A similar arrangement for pivotal and translational movement of the rearward end of the cross member 18 may also be used.

The actuator 16 is also pivotally mounted on the cross bar 22 and is able to move with the rear ends of the cross members 20. Two pistons 32 of the actuator are pivotally connected to a brace 34 that extends between the cross members 18. The cross members 18 and 20 are at each side and constrained to rotate about a common axle 36 that connects all cross members.

When the upper stretcher is moved to the lowered position, two conical recesses 38 at the rear of the upper frame slide over and rest on upwardly projecting posts 40 of the lower frame that end in a conical taper. The actuator 16 holds the upper frame on the lower frame particularly well at the rear of the stretcher as the cross members 20 and the actuator 16 are both mounted on the same cross bar 22, which cross bar is at the end of the rods 24 in the lowered position whereby the rods are able to resist significant bending moments. The actuator holds the upper frame on the lower frame by acting through the cross bars 18 that, in the lowered position, are pivotally connected to the upper frame at a location at the rear end region of the upper frame.

When the stretcher is moved to the lowered position, as shown in Figure 4, plate locks 42 located at either side of the upper frame 12 come down and snap over bars 44 at each side to lock the upper frame to the lower frame at the front region. The bars 44 each extend between plates 46 to restrict any sideways movement of the upper frame relative to the lower frame.

The plate lock 42 is shown in more detail in Figure 5.

The plate lock 42 includes three pivot pins 46,48,50 extending therethrough on which are respectively mounted first and second plates 52 and 54 and a latch plate 56.

Springs (not shown) bias the plate 52 in a clockwise direction, the plate 54 in an anti-clockwise direction and the latch plate 56 in a clockwise direction.

As the bar 44 abuts a camming surface 58 of the plate 54, that plate is urged against its spring bias in a clockwise direction with a curved surface 60 of the plate 54 pushing a cooperating surface 62 of the plate 46 in an anti-clockwise direction until the bar 44 is retained in an enclosure defined by an arcuate surface 66 on the plate 54 and the end 68 on the plate 52.

As the closing motion of the plate 54 occurs, a camming surface 70 of that plate urges the latch plate 56 in an anti-clockwise direction with a latch point 72 of the plate 56 resting first in a notch 74 and then in a notch 76 to hold the parts in the closed position.

When a release lever 78 is actuated, the latch plate 56 is caused to move in an anti-clockwise direction to urge the latch point 72 out of engagement with the notches to cause the plates 52 and 54 to spring back to the position shown.

In order to raise the stretcher from the lower position, the plate locks have to be released and the pistons of the hydraulic actuator must be extended. The plate locks 42 are released by an operative at the rear end of the trolley pulling a lever (not shown) on the rear of the upper frame. That pulling causes a wire 80 extending within one side member to pull a lever 82 rearwardly. The lever 82 in turn causes a link 84 to pivot in an anti-clockwise direction about the axis of a bar 86. The link 84 is angled and the remote end of the link 84 is connected to the lever 78 which is caused to be pulled upwardly thereby releasing the latch plate from the notches 76 and 78 to allow the plates 52 and 42 to spring to the position shown. The bar 86 extends across the trolley to release the plate lock at the other side.

The loading of the stretcher into an ambulance will now be described.

With the stretcher in the lowered position or raised position (usually the lowered position) the wheels 88 roll on the ambulance floor to move the stretcher towards a forward holder 90 mounted on the floor, as shown in Figure 7. The holder 90 includes rearwardly and converging rails 92 raised above the floor. The rails 92 abut a rearwardly converging channel 94 at the front of the lower frame, as shown in Figure 6, to guide the front of the stretcher in a sideways direction, if necessary, and to limit or prevent any sideways movement of the front of the trolley once the trolley is fully mounted in the ambulance. A bar 96 on the lower frame extends under the rails to prevent upwards movement of the front of the lower frame.

As the stretcher is being loaded a bar 98 attached to the rear of the lower frame at a lower elevation than the lower frame is brought into engagement with a clamp mechanism 100 mounted on the floor of an ambulance, as shown in Figure 8.

The clamp mechanism includes a raised base plate 102, two fixed rearwardly facing clamps 104, two movable clamps or catches 106, and a clamp engaging element 108.

The movable rear catches 106 are hinged about a horizontal bar 110. When the system is not in a locked position the movable catches 53 will be in an unengaged, lowered position. To move the clamps from their lower unengaged position to their raised locked position shown in Figure 8, a clamp engaging element 108 is moved from the position shown by the broken lines in Figure 4, rearwardly to the position shown in solid lines. AS the clamp engaging element 108 moves rearwardly it engages the rear of the clamps and, upon further movement, the clamps 106 pivot in an anti-clockwise direction to their engaged position shown. In this position the bar 104 is held and the rear of the lower frame is prevented from moving relative to the ambulance floor. A foot pedal 105 is able to be pushed to release the clamp by pushing the plate forwardly to the position shown in broken lines.

When the stretcher is in the lowered position and the lower frame is held at the front and back as described above, the upper frame is also held firmly on to the lower frame. Should the ambulance be involved in a crash the lower frame will stay attached to the floor. Further, the front of the upper frame will be firmly attached to the lower frame by the plate locks at either side. In addition the rear of the upper frame is held to the lower frame by the hydraulic actuator.

Should a patient require emergency treatment during transportation, the ambulance is parked and an operative can raise the lower frame by pulling on the wire 80 to release the plate locks and then operating hydraulic actuator. After the emergency treatment is complete, the stretcher can be lowered again by the actuator with the plate lock being automatically engaged. All this is effected without having to detach the lower frame from its secure mounting on the ambulance.

The stretcher includes a battery (not shown) in order to power the actuator. If desired, the stretcher may have electrical contacts 114 (shown in Figure 6) that are caused to be brought into contact with electrical contacts mounted on the forward holder (not shown) whereby the battery is automatically charged, if necessary, each time the stretcher is loaded.

The stretcher may include a control whereby the actuator is not able to be operated, when the upper frame is in the lowered position, without the plate locks being released.

For instance, a microswitch 120 shown in Figure 5 may be activated by the link 84 to allow the actuator to cause movement of the frames.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment (s) . The invention extends to any novel one, or any novel combination, of the features

disclosed in this specification (including any

accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

CLAIMS1. A stretcher including an upper frame and a lower frame, the upper frame being movable relative to the lower frame between an upper and a lower position in which, in the lower position the frames are closer together than in the upper position, the stretcher including a holder arranged to hold a region of the upper and lower frames together when the upper frame is in the lower position.
2. A stretcher as claimed in Claim 1 in which the holder comprises a releasable lock.
3. A stretcher as claimed in Claim 2 in which the releasable lock is arranged to act directly between the upper and lower frames.
4. A stretcher as claimed in Claim 2 or 3 in which the lock is arranged to be automatically engaged as the upper frame moves to the lower position.
5. A stretcher as claimed in Claim 4 in which the lock comprises a member on one of the frames entering a snap fitting on the other frame as the upper frame moves to the lower position.
6. A stretcher as claimed in Claim 5 in which the snap fitting comprises at least one retainer being pivoted by the member as the upper frame moves towards the lower position to a holding position in which the frames are held together.
7. A stretcher as claimed in Claim 6 in which the retainer is maintained in the holding position by a ratchet.
8. A stretcher as claimed in Claim 7 in which the retainer can be released by releasing the ratchet.
9. A stretcher as claimed in any of Claims 2 to 8 in which the releasable lock is located at one end region of the stretcher.
10. A stretcher as claimed in Claim 9 in which the releasable lock is arranged to be released by an operating member at the other end region of the trolley.
11. A stretcher as claimed in Claim 9 or 10 in which the stretcher is arranged to be held at one end region by the releasable lock and is also arranged to be held at the other end region when the upper frame is in the lower position.
12. A stretcher as claimed in any of Claims 2 to 11 in which the releasable lock is located at opposed side regions of the stretcher.
13. A stretcher as claimed in Claim 12 in which the releasable locks are connected whereby both locks are arranged to be simultaneously released.
14. A stretcher as claimed in any preceding claim in which the stretcher includes a powered actuator arranged to move the frames in at least one direction of the raised to lower or the lower to raised position.
15. A stretcher as claimed in Claim 14 in which the actuator is arranged to move the frame between both positions.
16. A stretcher as claimed in Claim 14 or 15 in which the actuator is arranged to hold the frame in at least one position.
17. A stretcher as claimed in Claim 16 in which the actuator is arranged to hold the frames in both positions.
18. A stretcher as claimed in Claim 16 or 17 in which the actuator is arranged to hold the frame in positions between the raised and lower positions.
19. A stretcher as claimed in any of Claims 14 to 18 in which the actuator includes an extendable and retractable member arranged to cause the movement of the frames.
20. A stretcher as claimed in Claim 19 in which the actuator includes two spaced parallel extendable and retractable members arranged to cause the movement of the frames.
21. A stretcher as claimed in any of Claims 14 to 19 in which one end region of the actuator is arranged to pivot relative to one of the frames at a first end region and to move pivotally and translationally relative to the other frames at a second end region as the frames move relative to each other.
22. A stretcher as claimed in Claim 21 in which the second end region of the actuator is arranged to be located at an end region of the frame on which it moves translationally when the upper frame is in the lower position.
23. A stretcher as claimed in Claim 22 in which the second end region is constrained to move translationally by a rail that is supported at a first end by an end region of the frame and that is supported at the other, second end at a location spaced from that end region of the frame.
24. A stretcher as claimed in Claim 23 in which the second end region of the actuator is connected to a slider that moves on the rail as the frames move relative to each other with the slider moving towards the front end of the rail as the upper frame is moved towards the raised position.
25. A stretcher as claimed in any preceding claim in which the stretcher includes at least one connector extending between the frames and being pivotally movable relative to one frame at a first end region of the connector and pivotally and translationally movable relative to the other frame at a second end. region.
26. A stretcher as claimed in Claim 25 in which the second end region of the connector is arranged to be located at an end region of the frame on which it is translationally movable when the upper frame is in the lower position.
27. A stretcher as claimed in Claim 25 or 26 when dependent on any of Claims 21 to 24 in which the second end region of the connector and the second end region of the actuator are arranged to move towards the same end region as the upper frame moves towards the lower position.
28. A stretcher as claimed in Claim 27 in which the second end region of the connector and the actuator move rotationally and translationally on the same frame.
29. A stretcher as claimed in Claim 28 in which the second end region of the connector and actuator are pivotally mounted on a common slider that moves translationally as the upper frame is moved to the lower position.
30. A stretcher as claimed in any preceding claim in which the stretcher includes a control that prevents the actuator from being able to move the upper frame away from the lower frame when the holder holds the frames together.
31. A stretcher as claimed in Claim 30 in which the control comprises a switch.
32. A stretcher as claimed in any preceding claim in combination with a stretcher securing arrangement, the securing arrangement including lower frame holding means arranged to restrain movement of the lower frame with the upper frame being movable relative to the lower frame when the lower frame is restrained from moving by the lower frame holding means.
33. A stretcher as claimed in Claim 32 in which the lower frame holding means is arranged to hold front and rear end regions of the lower frame.
34. A stretcher as claimed in Claim 32 or 33 in which at least one of the holding means is arranged to be automatically engaged upon movement of the stretcher to the holding means.
35. A stretcher as claimed in any of Claims 32 to 34 in which at least one of the holding means is arranged to guide at least one end of the stretcher in a sideways direction, if necessary, as the stretcher is moved in a forwards direction towards the holding means.
36. A method of operating a stretcher including an upper frame and a lower frame comprising moving the upper frame relative to the lower frame from a raised position to a lower position in which the upper frame is closer to the lower frame and holding the frames together when the upper frame is in the lower position.
37. A method as claimed in Claim 36 comprising causing the frames to be held together with a releasable lock.
38. A method as claimed in Claim 37 including causing the frame to be held at one end region of the frame by the releasable lock when the upper frame is moved to the lower position.
39. A method of operating a stretcher as claimed in any of Claims 36 to 38 comprising securing the lower frame in position and then moving the upper frame from the lower position to a raised position.
40. A method as claimed in any of Claims 36 to 39 when the stretcher is in accordance with any of Claims 1 to 31.
41. A method as claimed in any of Claims 36 to 39 comprising moving the upper frame relative to the lower frame when the lower frame is restrained from movement by the lower frame holding means of the stretcher securing arrangement as claimed in any of Claims 32 to 35.