GB2380664A

GB2380664A - Vertically adjustable stretcher

Info

Publication number: GB2380664A
Application number: GB0300551A
Authority: GB
Inventors: Jon Ellis
Original assignee: Ferno UK Ltd
Current assignee: Ferno UK Ltd
Priority date: 1999-03-30
Filing date: 1999-03-30
Publication date: 2003-04-16
Anticipated expiration: 2019-03-30
Also published as: GB2380664B; GB2380402A; GB0300551D0; GB0300546D0; GB2380403A; GB2348359A; GB9907160D0; GB2380403B; GB2380665A; GB0300549D0; GB2380665B; GB2348359B; GB2380402B; GB0300552D0

Abstract

A lower frame (10 Fig 1) is connected to an upper frame 12 by a first pair of parallel cross links 14 and a second parallel cross links 16. A hydraulic cylinder 38 can have a piston (40 Fig 5) extended therefrom to cause the upper frame to be raised. A pump lever 64 can be depressed to cause the raising of the upper frame with the lever also being actuatable to permit lowering. Control means are included to enable an operator to control the rate of movement of the upper frame relative to the lower frame. A sensor which may comprise a strain gauge or an hydraulic fluid pressure sensor is provided to indicate the weight of the patient or to indicate when a patient is too heavy for the specified weight of the trolley.

Description

STRETCHERS The present invention relates to stretcher apparatus and to a method of operating a stretcher. The present invention is particularly, although not exclusively applicable to wheeled stretcher trolleys.

In a known stretcher trolley a lower frame is connected to an upper frame by a scissor type linkage. A first link is pivotally connected to the forward end of the upper frame and to the rearward end of the lower frame. A second link is pivotally connected to the rearward end of the upper frame and the forward end of the lower frame. The links are pivotally connected together at an intermediate location between their ends. The second link, in addition to being pivotally connected to the lower frame is also slidably mounted on the lower frame.

The lower frame has wheels depending from each corner to allow the trolley to be moved. The upper frame can occupy a down position at which the frames are adjacent to each other or an up position in which the upper frame is spaced from the lower frame, with the upper frame being at waist height. In the down position the longitudinal extent of the links are almost parallel to each other. When the upper frame is lifted, which requires two people, one at each end, the scissor angle of the links opens up. During this movement the links all pivot about their connections to the frames and the second link slides along the lower frame towards the pivot mounting of the first link to the lower frame. A latch lock is provided to retain the upper frame in the up position. To lower the frame the latch is released and the operators support the upper frame as it is returning to the down position.

Clearly a significant amount of effort is required by the operators in raising and lowering the upper frame.

Furthermore, should the latch not be properly engaged or should the latch fail the upper frame can crash down onto the lower frame.

A prior proposal has been to include a spring action between the lower frame and the pivotal connection of the second link to that frame to urge the pivot of the lower link towards the pivot of the first link to the lower frame. Thus lifting of the upper frame is assisted by the frame and lowering of the upper frame resisted. However some lifting will be required by the operators.

Furthermore some support of the upper frame will be required when lowering that frame.

It is an object of the present invention to attempt to overcome at least some of the above described disadvantages.

According to one aspect of the present invention stretcher apparatus comprises a lower portion and an upper portion, the upper portion being movable relative to the lower portion between a first position, in which the upper portion is spaced from the lower portion, and a second position in which the upper portion is closer to the lower portion, the apparatus including control means actuatable by an operator that are arranged to move the upper portion from the second position to the first position.

The control means may be arranged to move the upper portion from the first position towards the second position.

When the upper portion is in the first position and the second position, the upper portion may be in substantially the same vertical position relative to the lower portion. The upper portion may be arranged to move in substantially the same vertical plane relative to the lower portion when

moving from the second position to the first position. This can assist the raising of the upper portion in confined spaces such as an ambulance.

The force provided by the control means may be variable, for instance to ensure that the upper portion is able to be moved from the second position to the first position when the stretcher is loaded or when more resistance to movement is provided.

The control means may be arranged to progressively move the upper portion.

The control means may be arranged to retain the upper portion in position relative to the lower portion.

There may be a plurality of first positions in which the upper portion is at different spacings from the lower portion.

The control means may be actuatable by the foot of an operator. The control means may include one lever that is arranged to control both the movement from the second to the first position and also the movement from the first to the second position. That lever may be movable, for instance repeatedly, downwardly in order to move the upper portion from the second position to the first position and the lever may be able to be raised in order to cause the upper portion to move from the first position to the second position. Alternatively the control means may include two levers, one being actuatable to cause the upper portion to move from the second position to the first position and the other being actuatable to cause the upper portion to move from the first position towards the second position. The rate of movement of the upper portion between either of the positions or both may be controllable by an operator.

The control means may include a piston and cylinder.

The piston and cylinder may be pivotally mounted relative to the upper and lower portions.

The axis of the pivot mounting of the piston and cylinder relative to the lower portion may be arranged to be below a frame of the lower portion, which frame is spaced from the ground. That pivot axis may be less than 220mm from the ground or less than 215mm from the ground or in the region of 213mm from the ground. The lower portion of the frame may be more that 230mm from the ground or more that 240mm from the ground or in the register of 210mm from the ground. The ratio of the height of the lower portion of the frame to the ground to the pivot axis may be less than 1.25 : or more than 1.10 : 1 or in the region of 1.16 : 1.

Part of the piston or cylinder may be connected to a member of the lower portion that part of the piston or cylinder is arranged to at least partially extend into when the upper portion moves from the first to the second position.

The extension of the piston may be arranged to cause movement of the upper portion from the second to the first position.

The control means may include a restrictor that is arranged to ensure a relatively even raising of the upper portion from the second to the first position or lowering of the upper portion from the first to the second position.

Cross members may connect the upper portion and the lower portion. The cross members may be pivotally connected at one end to the upper portion and at the other end to the lower portion and also pivotally connected to each other at an extent between their pivotal connections to the upper and lower portions. When the piston and

cylinder are pivotally connected to the upper and lower portions, the pivot connection may be about the same axis as one of the connections of the cross members to the upper or lower portions or may be between the pivot axes of the cross members to one of the members.

The pivot axis of at least one of the cross members may

be spaced from the ground by less than 245mm or less than 240mm or less than 235mm or in the region of 230mm. The ratio of height of a frame of the lower portion from the ground to the height of at least one of the pivot axes of the cross members may be less than 1.2 : 1 or more than 1.04 : 1 or in the region of 1.08 : 1.

At least one of the cross members may be movable relative to one of the portions in a translational direction.

Both of the cross members may be movable translationally relative to at least one of the upper or lower portions. Each of the cross members may be movable translationally relative to a different one of the upper and lower portions, in which case both of the upper and lower portions may be arranged to be translationally movable to the respective upper and lower portions towards what, in use, will be the end of the stretcher apparatus that is arranged to be the leg support end of the apparatus.

The extend of the pivotal connection of each cross member to the lower portion or the upper portion to the pivotal connection to each other may be substantially equal. For instance that extent to the lower portion may be

less than 460mm or less than 445mm or more than 400mm or more than 415mm or in the region of 430mm. That extent to the upper portion may be less than 525mm or less than 515mm or more than 470mm or more than 485mm or in the region of

500mm.

The stretcher apparatus may include sensing means arranged to sense a weight on the stretcher. The sensing means may be arranged to give an indication as to when the weight on the stretcher is excessive. Alternatively or additionally the sensing means may be arranged to give an indication of the weight of a person on the stretcher. The sensing means may comprise a strain gauge. Alternatively or additionally, when the piston and cylinder are hydraulically powered, the sensing means may comprise a measure of the pressure of the fluid.

The stretcher apparatus may include safety means arranged to prevent the lower frame from being moved from the second position to the first position when the weight of a patient exceeds a predetermined value. The safety means may comprise means to render the control means inoperative which may comprise blocking the hydraulic circuit when the control means includes hydraulic means.

According to another aspect of the present invention a method of operating stretcher apparatus in which the apparatus comprises a lower portion and an upper portion with the upper portion being movable relative to the lower portion between a first position, in which the upper portion is spaced from the lower position, and a second position in which the upper portion is closer to the lower portion comprises actuating control means to cause the upper portion to move from the second position to the first position.

The method may comprise causing the upper portion to move from the second to the first position or, alternatively or additionally, from the first position to the second position, in substantially the same vertical orientation relative to the lower portion.

The method may comprise causing the upper portion to move from the first position towards the second position by actuating control means.

The method may comprise causing the control means to act at a location lower than a frame of the lower portion of the stretcher.

The method may comprise causing the control means to move the upper portion from the first position towards the second position or from the second position towards the first position or both at a substantially constant rate.

The method may comprise maintaining the upper portion and the lower portion at a distance spaced from each other by using the control means.

The control means may comprise fluid control means and the method may comprise pressurising that fluid by means of the foot or releasing pressure by means of the foot of an operator.

The method may comprise monitoring the weight on the stretcher and the method may comprise monitoring the weight by monitoring the pressure of the fluid that is arranged to comprise the control means.

The present invention includes any combination of the herein referred to features or limitations. The present invention can be carried into practice in various ways but several embodiments will now be described, by way of example, and with reference to the accompanying drawings in which :- Figure 1 is a side view of the front end of a first embodiment of a stretcher trolley in a partially raised

position; Figure 2 is a view similar to Figure 1 ; Figure 3 is a view similar to Figure 1 with the upper frame in the fully collapsed position; Figure 4 is a side view of a second embodiment of a stretcher trolley in the raised position; Figure 5 is a view similar to Figure 4; Figure 6 is a side view of a third embodiment of a stretcher trolley in a raised position; Figure 7 is a detailed view showing the trolley in Figure 6 in a fully clamped position; Figure 8 is a view similar to Figure 6 showing more clearly the operative components that allow the trolley of Figure 6 to be raised and lowered; Figure 9 is a detailed view showing the pivot points for an hydraulic cylinder and one of the cross members: Figure 10 is a side view from underneath showing the corporation of one of the cross members and the pivot point of the hydraulic cylinder with the lower frame; and Figure 11 is a view showing the hydraulic pump of the trolley together with a pivot point of the other cross member.

Although three embodiments are being described, like components will be given the same reference numeral.

In Figures 1 to 3 a lower frame 10 is connected to an

upper frame 12 by a first pair of parallel cross links 14 and a second pair of parallel cross links 16. The links 14 and 16 are pivotally connected at an intermediate location by a rod (not shown). The upper frame is connected to each of the links by a pivot 20 (only the pivot for the second cross links 16 is shown). The lower end of each of the cross links 14 and 16 are connected to the lower frame by a pivot 22 (only the pivot 22 with the cross links 14 is shown).

The pivot 22 for the cross links 14 is provided by having an"I"shaped bar 24 extending across the two spaced parallel side members 26 of the lower frame 10. The bar 24 engages each of the side members 26 by a tube 28 surrounding the side members 26 and being secured thereto.

The central round portion of the"I"bar that extends between the side members 26 is engaged by the cross links 14 with a tubular section at the end of those cross links 14 pivotally surrounding the bar 24. Similar"I"shaped bars engage the other points of pivotal connections at the upper end of each of the cross links and at the lower end of the other cross link 16 (not shown). In addition though for the lower connection of the cross link 16, instead of the tube 28 being fastened to the side member 26, at the location where the lower end of the cross link 16 is connected to the side member 26, that tube is able to slide along the side member 26 towards or away from the point of connection of the cross link 14 to the lower frame.

It can be seen that the upper frame can be raised or lowered away from or towards the lower frame with the movement being guided by the pivotal connections of the cross links with the respective frames and with the connection of the cross link 16 to the side member 26 sliding respectively towards or away from the connection of the cross link 14 to the frame.

In the lower position shown in Figure 3 parallel side members 30 of the upper frame rest on upstanding pillars 32 that extend from each of the four corners of the lower frame. Wheels 34 depend downwardly from each of the four corners of the lower frame to provide the means for manoeuvring the stretcher trolley.

The upper frame has a mattress 36 located thereon to support patients whilst they are being manoeuvred.

All of the above description relates to conventional well known stretcher trolleys.

In addition though the stretcher trolley shown in Figures 1 to 3 includes means for raising and lowering the upper frame without the operator having to lift and lower the upper frame directly. These means comprise an hydraulic cylinder 38 that is pivotally connected to the "I"shaped bar 24, between the locations where the cross links 14 are connected to that bar. A piston 40 from the cylinder 38 is pivotally connected to the"I"shaped bar to which the upper ends of the cross links 14 are connected to the upper frame, between those points of connection. Thus it can be seen that when the piston 40 is extended from the cylinder 38 the upper frame will be raised with the motion of the links being as described above. Conversely, when a piston 40 is retracted into the cylinder the upper frame will move down towards the lower frame, ultimately reaching the position shown in Figure 3.

Fluid to cause the hydraulic cylinder to move is provided by a pump 42. This pump 42 is connected to a cross member 44 that extends between the side members 26 of the lower frame at a location towards the front of the trolley.

A pump lever 64 extends from the pump 42 towards the

front of the trolley and a parallel release lever 48 extends adjacent to the pump lever 64 in the same direction.

The pump lever 64 is pivotally mounted on the pump 42 and is biased towards an upper position. An operator standing at the front of the trolley can depress the pump lever repeatedly to cause fluid from the pump to flow through a flexible tube 50 to the lower end of the hydraulic cylinder 38 to force the piston 40 out of the housing to raise the trolley.

If desired there can be a restriction neck in the fluid flow, either in the pump or in the housing, to ensure that, in spite of the fact that the pump lever is being repeatedly depressed and then raised and then depressed again, the increase in fluid in the hydraulic cylinder is at a substantially constant rate to allow the trolley to be raised evenly. The pressure alone in the hydraulic cylinder can, if necessary, be sufficient for the upper frame to remain in a raised, or the upper position.

The hydraulic system may include a restrictor that is arranged to come in to operation when a patient in excess of 27 stones or 181. 4kg is placed on the trolley. The restrictor may act to block the hydraulic fluid flow necessary to push the hydraulic piston out of the cylinder to prevent the upper frame from being raised. This safeguards the trolley and ensures that it operates within its normal limits, without undue strain and prevents operators from abusing the trolley.

In order to cause the upper frame to move towards the lower frame the release lever can be depressed by the operator. This release lever may either be fully depressed or may be partially depressed to control the rate of descent. In this respect, the partial depression of the

release lever will allow a slower rate of descent. Alternatively, there may be a restriction in the fluid flow from the hydraulic cylinder to the pump to ensure that the rate of descent is even and, alternatively or additionally, to ensure that the rate of descent does not exceed a predetermined speed, for example, for a given weight on the upper frame.

Raising of the upper frame from the bottom position to the top position may be arranged to be achieved by twelve depressions of the pump lever 64. A restrictor may be included in the hydraulic cylinder such that, in the event that the flexible tube 50 fractures or in the event that there is a leak elsewhere in the system, descent of the trolley is slow and at a safe speed.

Although not shown, a sensor may be provided to give an indication of the weight of a patient on the trolley. This sensor may comprise a strain gauge located at an appropriate place, for instance on the piston 40. The sensor alternatively could be a sensor of the pressure in the hydraulic cylinder or the pump which is proportional to the weight of a person on the trolley. The sensor could be arranged to indicate the weight of that person and, alternatively or additionally, could indicate when a person is too heavy for the specified weight of the trolley.

The trolley shown in Figures 4 and 5 will now be described. However, it will be appreciated that this trolley may have any of the features of the above described trolley as indeed may the trolley shown in Figures 6 to 11.

In Figures 4 and 5 the upper pivot mountings of the cross links 14 and 16 are as described above. The lower pivot point of the links 16 though is provided by pivotally connecting the links with a central beam 52 that is connected to the lower frame 10 at each end and that

extends between and parallel to the side members 26.

The forward end of the cross links 14, at the lower end thereof, are pivotally connected to the beam 52 and are also slidable along a rail mechanism 54 in the directions shown by the arrows 56.

The hydraulic cylinder 38 is pivotally connected to the beam 52 by a rod 58. The pivot 58 is located between the points of connection of the cross links 14 and 16 to the beam 52. The upper end of the piston 40 is connected to a cross member 60 that extends between the cross links 14 towards the top of those links. The beam 52 includes an opening 62 that the cylinder can move into when the upper frame is moved back down towards the lower frame.

The pump 42 is located towards the front of the trolley. In this embodiment though a single operating lever 64 is biased towards an intermediate position whereby, repeated depression of the lever 64 against a resilient bias causes fluid to enter the cylinder to power the piston out and to move the upper frame away from the lower frame. In addition the lever 64 can be raised from the position shown to cause fluid to be able to move from the hydraulic cylinder back into the pump thereby allowing the upper frame to move down towards the lower frame.

Restrictions can be provided as referred to in the first embodiment.

It can be seen that the frame can be lifted and lowered under a controlled force without an operator ever having to touch the upper frame to urge it upwardly, or to resist its upward movement or to push the upper frame downwardly or to support the upper frame whilst it is moving downwardly.

In the embodiment referred to in Figure 6 to 11 cross

links 16 are pivotally connected to the base frame on the right hand side of those drawings by the pivot 22 shown in Figure 11. The other end of the cross links 16 are connected to the upper frame 12 by a pivot 66. This pivot 66 is mounted on a pair of grooved wheels 68 that are able to roll along a horizontal slot 70 depending downwardly from each side of the upper frame 12. The slot 70 is closed at either end.

A pair of parallel cross links 14 are pivotally connected to the upper frame by the pivot 20. The cross links 14 are pivotally connected to the lower frame and are also able to slide horizontally relative to the lower frame.

Figure 9 shows how the lower end of the hydraulic cylinder 38 and the cross link 14 are connected to the lower frame. A pair of spaced parallel square section bars extend between the ends of the lower frame and within the lower frame. From the lower end of those bars projects a slide edge 76. A U-shaped bracket 78 has the top end of the U turned over to extend over each of the slide edges 76 with the bracket 78 then extending downwardly, beneath the bars 74 and across the bars 74.

The cross links 14 are connected to the bracket 78 by a pivot 72. The axis of the pivot 72 is beneath the lowermost extent of the bars 74. In this respect, the distance from the downwardly facing surface of the bars 74 to the floor is 248mm and the distance from the pivot 72 to the floor is 213mm.

The hydraulic cylinder 38 is connected by a pivot 80 to a U-shaped bracket 82 that is connected to the top of the bars 74 and extends over the upwardly facing surfaces of those bars and then downwardly, beneath those bars and across those bars 74. The pivot 80 is at a distance of

213mm from the floor.

As shown in Figure 11, the cross links 16 are connected by the pivot 22, to a bracket 84 and extends downwardly from the side members of the lower frame. The height of the pivot 22 from the floor is 233mm.

When the upper frame moves to the position shown in Figure 6 to the position shown in Figure 7, the cross links move about their pivotal connections to the upper and lower frames respectively. The cross links 14 also move about their pivots 72 with the bracket 78 sliding along the edges 76, to the left when viewed in Figure 9. Also at the same time the cross links 16, at the upper end, move about the pivot 66 with the grooved wheels 68 rolling along the slot 70, to the left when viewed in Figure 6.

In use, the head of the patient is arranged to be approximately over the forward wheels 44 of the trolley.

Most of the weight of a patient is in their upper torso.

Accordingly, most of the weight of the patient, when the trolley is in the raised position, will be in the region of or between the points of connection of the cross links 14 and 16 with the upper and lower frames. Thus the support is provided for the patient by the cross links where it is most needed.

Furthermore, when the upper frame is raised relative to the lower frame, because of the action of the grooved wheels and the U-shaped frame 78, the upper frame is not tilted to any noticeable degree during the raising and lowering. In addition, the upper frame remains in its point of alignment with the lower frame so that only vertical movement occurs rather than the upper frame moving in the forward or rearward direction relative to the lower frame during raising and lowering. These are important features, particularly where the trolley is used in an ambulance for

the reasons described below.

In an ambulance, space is extremely constricted. In the past, the trollies have occupied a collapsed position only in the ambulances. That is because the trolleys have to be loaded into the ambulance in the collapsed position, and there is then not room for personnel to be located at either end within the ambulance to lift and lock and then lower the trolley. In the present invention, because of the hydraulic lift and lowering mechanism that is provided, it is only necessary for one operator to stand at the end of the trolley and then pump the lever with their foot. The operator does not have to bend down and accordingly any space restriction behind the operator caused by that bending is not of relevance.

Furthermore, the hydraulic action allows the trollies to be elevated to any height between the bottom and the top positions and held in those positions. Tests have shown that with the weight double that which can normally be expected on the trolley, there is no detectable descent of the trolley from a raised position over a 24 hour period.

The action of the trolley is assisted by the following dimensions of the cross links from their pivot points to the location of the pivot 86 where the cross links 14 and 16 are connected together.

The length of the cross link 14 from the pivot 72 to the pivot 86 is 431mm and the length of those links from the pivot 86 to the pivot 20 is 508mm. The length of the cross member 16 from the pivot 22 to the pivot 86 is 430mm and the length from that pivot 86 to the pivot 66 is 496mm.

Figure 7 shows the extent to which the upper frame can be lowered relative to the lower frame. From the top of the upper frame members 12 to the ground, in a collapsed

position shown in Figure 7, is 422mm (with the distance from the lower portion of the lower frame to the ground being 248mm). The distance of the top of the upper frame members from the ground in the raised position is 900mm.

This gives an idea of the versatility of the trolley.

The pivots 72,80 and 22 are all located a significant distance beneath the lower frame allowing the trolley to occupy the compact position as shown in Figure 7. This also affords a mechanical advantage both for the hydraulic cylinder and the cross links 14 and 16 allowing the cross links to be able to be pushed up from that extremely collapsed position, in which the cross links 14 and 16 appear almost parallel to each to the raised position shown in Figure 6.

Actuation of the hydraulic lever to cause the raising and lowering of the trolley may be as any of the options previously described.

The reader's 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

CLAIMS 1. Stretcher apparatus comprising a lower portion and an upper portion, the upper portion being movable relative to the lower portion between a first position, in which the upper portion is spaced from the lower portion, and a second position in which the upper portion is closer to the lower portion, the apparatus including control means actuatable by an operator that are arranged to move the upper portion from the second position to the first position and that are arranged to move the upper portion from the first position towards the second position, the rate of movement of the upper portions between at least one position to the other position being controllable by an operator.
2. Apparatus as claimed in Claim 1 in which, when the upper portion is in the first position and the second position, the upper portion is in substantially the same vertically aligned position relative to the lower portion.
3. Apparatus as claimed in Claim 3 in which the upper portion is arranged to move in substantially the same vertical plane relative to the lower portion when moving from the second position to the first position.
4. Apparatus as claimed in any preceding claim in which the control means are arranged to progressively move the upper portion.

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5. Apparatus as claimed in any preceding claim in which the control means are arranged to retain the upper portion in position relative to the lower portion.
6. Apparatus as claimed in any preceding claim in which there are a plurality of first positions in which the upper portion is at different spacings from the lower portion.
7. Apparatus as claimed in any preceding claim in which the control means include one lever that is arranged to control both the movement from the second to the first position and also the movement from the first to the second position.
8. Apparatus as claimed in Claim 7 in which the lever is movable, in order to move the upper portion from the second position to the first position.
9. Apparatus as claimed in Claim 7 or 8 in which the lever is able to be raised in order to cause the upper portion to move from the first position to the second position.
10. Apparatus as claimed in any preceding claim in which the control means includes two levers, one being actuatable to cause the upper portion to move from the second position to the first position and the other being actuatable to cause the upper portion to move from the first position towards the second position.
11. Apparatus as claimed in any preceding claim in which the control means include a piston and cylinder.

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12. Apparatus as claimed in Claim 11 in which the piston and cylinder are pivotally mounted relative to the upper and lower portions.
13. Apparatus as claimed in Claim 11 or 12 in which the axis of the pivot mounting of the piston and the cylinder relative to the lower portion are arranged to be below a frame of the lower portion which frame is spaced from the ground.
14. Apparatus as claimed in Claim 13 in which the pivot axis is less than 220 mm from the ground.
15. Apparatus as claimed in either of Claims 11 or 12 in which the lower portion of the frame is more than 230 mm from the ground.
16. Apparatus as claimed in any of Claims 11 to 15 in which the ratio of the height of the lower portion of the frame to the ground relative to the distance from the lower portion to the pivot axis is less than

1.25 : 1.
17. Apparatus as claimed in any of Claims 13 to 16 in which the ratio of the height of the lower portion of the frame to the ground compared to the ratio of the height of the lower portion to the pivot axis is more than 1.10 : 1.
18. Apparatus as claimed in any of Claims 11 to 17 in which part of the piston or cylinder is connected to a member of the lower portion with part of the piston or cylinder being arranged to at least partially extend into the area occupied by the lower frame when the

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upper portion moves from the first position to the second position.
19. Apparatus as claimed in any preceding claim including a restrictor that is arranged to ensure a relatively even raising of the upper portion from the second to the first position.
20. Apparatus as claimed in any preceding claim including cross members that connect the upper portion with the lower portion.
21. Apparatus as claimed in Claim 20 in which the cross members are pivotally connected at one end to the upper portion and at the other end to the lower portion and in which the cross members are also pivotally connected to each other at an extent between their pivotal connections to the upper and lower portions.
22. Apparatus as claimed in Claim 20 or 21 including a pivotally connected piston and cylinder in which the pivot connection is about the same axis as one of the connections of the cross members to the upper or lower portions.
23. Apparatus as claimed in any of Claims 20 to 22 in which, when the piston and cylinder are pivotally connected to the upper and lower portions, the pivot connection is arranged to be between the pivot axes of the cross members to one of the upper or lower portions.

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24. Apparatus as claimed in any of Claims 20 to 23 in which the pivot axis of at least one of the cross members is spaced from the ground by less than 245 mm.
25. Apparatus as claimed in any of Claims 20 to 24 in which the ratio of the height of a frame of the lower portion from the ground to the height of at least one of the pivot axes of the cross members is less than

1.2 : 1.
26. Apparatus as claimed in any of Claims 20 to 25 in which the ratio of the height of a frame of the lower portion from the ground to the height of at least one of the pivot axes of the cross members is more than

1.04 : 1.
27. Apparatus as claimed in any of Claims 20 to 26 in which at least one of the cross members is movable relative to one of the portions in a translational direction.
28. Apparatus as claimed in any of Claims 20 to 27 in which both of the cross members are movable translationally relative to at least one of the upper or lower portions.
29. Apparatus as claimed in Claim 28 in which each of the cross members is movable translationally relative to a different one of the upper and lower portions.
30. Apparatus as claimed in any Claim 20 or any claim when dependent upon Claim 20 in which the extent of the pivotal connection of each cross member to the lower portion or the upper portion to the pivotal connection to each other is substantially equal.

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31. Apparatus as claimed in any preceding claim including sensing means arranged to sense a weight on the stretcher.
32. Apparatus as claimed in Claim 31 in which the sensing means are arranged to give an indication as to when the weight on the stretcher is excessive.
33. Apparatus as claimed in Claim 31 or 32 in which the sensing means are arranged to give an indication of the weight of a person on the stretcher.
34. Apparatus as claimed in any of Claims 31 to 33 in which the sensing means comprise a strain gauge.
35. Apparatus as claimed in any of Claims 31 to 34 in which, when a piston and cylinder comprise the control means and are hydraulically powered, the sensing means comprise a measure of the pressure of the fluid.
36. Apparatus as claimed in any preceding claim including safety means arranged to prevent the lower frame from being moved from the second position to the first position when the weight of a patient exceeds a predetermined value.
37. Stretcher apparatus including control means to vary the rate of movement substantially as herein described with reference to, and as shown in any of the accompanying representations.
38. A method of operating stretcher apparatus in which the apparatus comprises a lower portion and an upper

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portion with the upper portion being movable relative to the lower portion between a first position, in which the upper portion is spaced from the lower portion and a second position in which the upper portion is closer to the lower portion comprising actuating control means to cause the upper portion to move from the second position to the first position and from the first position to the second position with the rate of movement of the upper portion between at least one position to the other position being controlled by an operator.
39. A method as claimed in Claim 38 comprising causing the upper portion to move from the second to the first position or, alternatively or additionally, from the first position to the second position in substantially the same vertical orientation relative to the lower portion.
40. Apparatus as claimed in either of Claims 38 or 39 comprising causing the upper portion to move from the first position towards the second position by actuating control means.
41. Apparatus as claimed in any of Claims 38 to 40 comprising causing control means to act at a location lower than a frame of the lower portion of the stretcher.
42. A method as claimed in any of Claims 38 to 41 comprising monitoring the weight on the stretcher.

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43. A method as claimed in Claim 42 comprising monitoring the weight by monitoring the pressure of fluid that is included in the control means.
44. A method of operating stretcher apparatus by control means varying the rate of movement substantially as herein described, with reference to, and as shown in any of the accompanying representations.
45. A method of operating stretcher apparatus as claimed in any of Claims 38 to 44 in which the apparatus is in accordance with any of Claims 1 to 37.