GB2542583B

GB2542583B - Stretcher incorporating a wheel assembly

Info

Publication number: GB2542583B
Application number: GB1516850.3A
Authority: GB
Inventors: Thomas Mason James
Original assignee: Ferno UK Ltd
Current assignee: Ferno UK Ltd
Priority date: 2015-09-23
Filing date: 2015-09-23
Publication date: 2019-08-21
Anticipated expiration: 2035-09-23
Also published as: GB201516849D0; GB2542582A; GB2542584A; GB2542583A; GB201516850D0; GB201516852D0; GB2542582B; GB2542584B

Description

STRETCHER INCORPORATING A WHEEL ASSEMBLY

FIELD

[01] The present idea relates to a stretcher incorporating a wheel assembly and a method of locking and unlocking a wheel assembly on a stretcher.

BACKGROUND

SUMMARY

[02] According to the present invention there is provided an apparatus and method as set forth in the appended claims. Other features of the invention will be apparent from the dependent claims, and the description which follows.

[03] According to an aspect a stretcher incorporating a wheel assembly includes a wheel rotatable about its own first axis, the wheel being mounted on a bracket that is rotatable about an upwardly extending second axis and a locking member that is movable from a first, locked position in which the bracket is prevented from rotating about the second axis and a second, unlocked position in which the bracket is able to rotate about the second axis with the locking member being movable from at least one of its positions upon activation of a solenoid, in which the bracket including an opening and in which the locking member is arranged to extend into the opening when the bracket is in the locked position, and in which the bracket includes a guide surface, or both the bracket and locking member each include a guide surface, arranged, in use, when the opening and locking member are not aligned and the locking member is moved towards the locked position, to guide the locking member towards the opening upon rotation of the bracket about the second axis and in which, in use, when the locking member does not contact the bracket when the locking member is moved towards the locked position, rotation of the bracket about the second axis is arranged to bring the locking member into contact with the guide surface of the bracket.

[04] The locking member may be movable between both positions upon activation of the solenoid.

[05] The solenoid may be a latching solenoid whereby no power is consumed when the locking member is in the first or second position.

[06] The solenoid may be biased towards the locked position.

[07] At least one guide surface may be provided on the bracket. The guide surface may extend downwardly away from the opening.

[08] The locking member may be caused to move against the bias when moving over the guide surface towards the opening.

[09] At least one guide surface may be provided on the locking member.

[10] The solenoid may be activated from a region remote from the wheel assembly.

[11 ] According to another aspect a method of locking or unlocking a bracket of a wheel assembly on a stretcher in which the wheel assembly is as herein referred to comprises causing the locking member to move between at least one of the positions by activating the solenoid and causing the locking member to move towards the locked position when the opening and locking member are not aligned and in which the locking member does not contact the bracket and then causing rotation of the bracket about the second axis to bring the locking member into contact with the bracket whereby contact with the guide surface of the bracket causes the locking member to move towards and then into the opening to prevent the bracket from rotating about the second axis thereby locking the bracket.

[12] The method may comprise activating the solenoid from a region remote from the wheel assembly.

BRIEF DESCRIPTION OF DRAWINGS

[13] For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which: [14] Figure 1 is a perspective view of a stretcher 10 in a raised position; [15] Figure 2 is a perspective view of a stretcher 10 in a lowered position; [16] Figure 3 is a view from below of part of an upper part of a raise and lower mechanism; [17] Figure 4 is a view from above of part of a lower part of a raise and lower mechanism; [18] Figure 5 is a view from below of part of a mechanism to raise and lower part of support panels that are included in a body support; [19] Figure 6 is a view from below of another part of the mechanism to raise and lower part of the support panels; [20] Figure 7 is a perspective view of the support panels from above; [21] Figure 8 is a perspective view from beneath of the support panels showing the mechanism to raise and lower support panels; [22] Figure 9 is a detail view showing the connection between two support panels; [23] Figure 10 is a perspective view of a wheel assembly for the stretcher 10, with a wheel able to rotate about an upwardly extending axis; [24] Figure 11 is a view similar to Figure 10 with the wheel being restrained from rotating about an upwardly extending axis, and; [25] Figure 12 is a view similar to Figure 11 with the wheel about to be restrained from rotating about an upwardly extending axis.

DESCRIPTION OF EMBODIMENTS

[26] As shown in Figure 1 and 2 a stretcher 10 includes a body support 12 which may be covered by a mattress 14. The body support 12 may be attached to an upper frame 16. A lower frame 18 may be provided. The upper frame 16 may be movable between a raised position, as shown in Figure 1 and a lowered position as shown in Figure 2.

[27] A power unit 20 may be provided to raise the upper frame relative to the lower frame.

[28] At least one pair and preferably two pairs of cross members 22 and 24 may be used to effect the movement of the upper frame 16 relative to the lower frame.

[29] The power unit 20 may be connected to at least one and preferably two cross members by an actuator 32 extending from the power unit 22 or 24 and that connection may be via a pivot 26. The power unit 20 may be pivotally connected to the lower frame via a pivot 28.

[30] The cross members may be connected via a pivot 30.

[31] During raising or lowering of the upper frame relative to the lower frame at least one end of at least one of the cross members may slide and pivot relative to the lower frame or the upper frame or both. Both cross members of the or each pair of cross members may slide and pivot relative to the lower frame or the upper frame or both. One cross member may pivot and slide relative to the lower frame and may move about a pivot 36 only relative to the upper frame. The other cross member in the pair may pivot and slide relative to the upper frame and move about a pivot 34 only relative to the lower frame.

[32] During raising or lowering of the upper frame relative to the lower frame at least one actuator may extend from, or retract towards the power unit.

[33] The sliding and pivot connection of the cross member 22 is shown in Figures 3 and 4.

[34] In Figure 3 the upper frame sliding and pivot connection is shown. The cross member 22 includes a slide 38 and a pivot 40. The axis of the pivot 40 extends across the longitudinal axis of the stretcher. The slide 38 may be restricted from movement about an axis extending across the stretchers which may be a horizontal axis. For instance the slide 38 may include two parallel slides which may be rails 42 and 44 which guides or rails may be spaced from each other in a direction across the stretcher and preferably the rails 44, 44 are at the same level. The guides may be linear bearings.

[35] In Figure 4 the lower frame 18 sliding and pivot connection is shown. The cross member 22 includes a slide 46 and a pivot 48. The axis of the pivot 48 extends across the longitudinal axis of the stretcher. The slide 46 may be restricted from movement about an upwardly extending axis which may be a vertical axis. For instance the slide 46 may include a guides which may be rails 50 and 52 which guides or rails may be spaced from each other in an upwards direction which may be a vertical direction. The guides may be linear bearing guides.

[36] Alternatively the guide 46 may be provided on the upper frame and the guide 38 may be provided on the lower frame.

[37] The above arrangement contrasts to conventional guides that where the pivot pin at the upper and lower frames extends through parallel slots in the upper and lower frames. In such slots wear can occur and such wear at the upper and lower frames can cause the upper frame to be able to move from side to side which effect is exaggerated as the wear is in the same direction at both the upper and lower frames. The arrangement shown in Figures 3 and 4 provides greater stability of the upper and lower frame as the slides 38 and 46 are restricted from movement about opposed directions.

[38] As shown in Figure 7 and 9 the body support 12 may include a plurality of support panels 54, 56, 58, 60. There may be four such panels. At least one panel may pivot relative to an adjacent panel. The panels may be plastic.

[39] At least two adjacent panels may be connected together by a common connector 62. The connector 62 may enable pivotal connection of one panel relative to an adjacent panel. The connector may extend through an opening defined by a part formed integrally with the panel. This contrasts with conventional stretchers where a body supporting plate is attached to a frame and that frame is then pivotally connected to the upper frame.

[40] At least two adjacent panels may include at least one male member 64 of one panel extending into a female member 66 of the other panel. There may be a plurality of male members 64 on each panel extending into a plurality of female members of each panel. There may be three male members of one panel and two female members each extending into female members of the other panel. One panel may include male members 68 at each end that lie outside of the male members on the other panel.

[41] With such interlocking provided by the members any relative side to side or pivotal movement about the longitudinal axis of the stretcher is minimised.

[42] The adjacent male members may be a close fit and may be a tight fit.

[43] The connector 62 may pass through each male member. With such an arrangement the number of connections between the panels is reduced as separate pivots between adjacent panels may not be required. The connector may assist in restricting side to side movement of adjacent panels or pivotal movement of adjacent panels across the longitudinal axis of the stretcher.

[44] As shown in Figures 5, 6 and 8 at least one panel may be pivotal relative to another panel about an axis extending across the stretcher.

[45] In one arrangement one end panel 54 may be raised by a power unit 70 connected to a lever 72. Upon activation of the power unit 70 an actuator may extend from the power unit to cause the end panel to be inclined via a pivot which may be defined by the connector 62 in the region of the head panel and the adjacent panel 56. The power unit 70 may pivot about an axis 74 and the actuator may also pivot relative to the lever 72.

[46] In one arrangement a panel such as panel 58 may be raised by a power unit 76 connected to a lever 78. Upon activation of the power unit 76 an actuator may extend from the power unit to cause the panel 58 to be inclined via a pivot in the region of the junction of the panels 58 and 56. The power unit may pivot about the axis 74 and the actuator may also pivot relative to the lever 78.

[47] In an alternative embodiment either or both power units may be pivotally connected to the levers with the actuator being pivotally connected about the axis 74.

[48] Where both power units 70 and 76 are provided it can be seen that only a single pivot axis 74 need be provided. This saves weight on the stretcher and makes the assembly of the stretcher simpler.

[49] The lever 72 may be integrally formed with the panel.

[50] As shown in Figure 1, the stretcher is able to be supported and conveyed by wheels 80. Each wheel may be able to rotate about an upwardly extending axis 82, which may be a vertical axis, shown in Figure 10 as well as about its own axis 84. The axes 82 and 84 may be offset from each other whereby a projection of each axis does not pass through either axis.

[51] At least one wheel assembly 86 is able to be restrained from rotating about the upwardly extending axis 82. There may be two wheel assemblies at at least one end that may be able to be restrained from rotating about the upwardly extending axis or three or four assemblies may be able to be restrained from rotating about the upwardly extending axis 82.

[52] The wheel assembly 86 may include a first pivot mount 88 which may be fast with the lower frame 18 which pivot mount includes an axle 90 which defines the pivot axis 82. The axle 90 is connected to a bracket 92. The wheel 80 may be connected to the bracket 92 at a location spaced from the pivot axis 82 by an axle 94 that defines the pivot axis 84 which axis may extend horizontally.

[53] A lock 96 is provided on the bracket or a part fast with the lower frame which lock may be operable to restrain rotation about the axis 82 or to permit rotation about the axis 82.

[54] In the position shown in Figure 10 rotation about the axis 82 is permitted.

[55] In the position shown in Figure 11 a plunger 98 from the lock 96 extends into an opening 100 in the bracket 92 to prevent rotation about the axis 82.

[56] The plunger may be moved downwardly to enter the opening 100 upon activation of a solenoid 102.

[57] If the opening 100 is not in alignment with the plunger 98, as shown in Figure 12, then the plunger engages with a guide surface 104 which surface may be provided on both sides of the opening. Alternatively or additionally the plunger may include a guide surface 106 which may be provided on both sides of the plunger 98.

[58] The guide surface 104 may comprise a surface extending downwardly and away from the opening 100. The guide surface 106 on the plunger may comprise a surface extending upwardly and towards the opening when the plunger is not aligned with the opening.

[59] In the position shown in Figure 12 the plunger may be urged towards the guide surface 104 by resilient means which may comprise a spring. As the stretcher is moved the bracket may rotate about the upwardly extending axis 82 with the or each guide surface urging the plunger upwardly until the plunger is aligned with the opening at which point the plunger then moves down into the opening to prevent further rotation about the axis 82.

[60] If the plunger is not in contact with the bracket when the plunger is moved downwardly then rotation of the bracket about the axis 82 will bring the bracket into the position shown in Figure 12 and then into the position shown in Figure 11.

[61] The lock may be removable from the locked position shown in Figure 11 to the unlocked position shown in Figure 10 upon activation of the solenoid.

[62] The solenoid may be activated by a control 108 which may be provided in the region of a handle 110 of the stretcher, as shown in Figure 2.

[63] The solenoid may be a latching solenoid whereby the plunger is able to occupy the locked or unlocked position without the constant application of an electrical current. Such latching solenoids are well known and may comprise a permanent magnet latching solenoid or a residual magnetism latching solenoid.

[64] Although preferred embodiment(s) of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made without departing from the scope of the invention as defined in the claims.

Claims

1. A stretcher incorporating a wheel assembly including a wheel rotatable about its own first axis, the wheel being mounted on a bracket that is rotatable about an upwardly extending second axis and a locking member that is movable from a first, locked position in which the bracket is prevented from rotating about the second axis and a second, unlocked position in which the bracket is able to rotate about the second axis with the locking member being movable from at least one of its positions upon activation of a solenoid, in which the bracket including an opening and in which the locking member is arranged to extend into the opening when the bracket is in the locked position, and in which the bracket includes a guide surface, or both the bracket and locking member each include a guide surface, arranged, in use, when the opening and locking member are not aligned and the locking member is moved towards the locked position, to guide the locking member towards the opening upon rotation of the bracket about the second axis and in which, in use, when the locking member does not contact the bracket when the locking member is moved towards the locked position, rotation of the bracket about the second axis is arranged to bring the locking member into contact with the guide surface of the bracket.

2. The stretcher incorporating a wheel assembly as claimed in claim 1 in which the locking member is movable between both positions upon activation of the solenoid.

3. The stretcher incorporating a wheel assembly as claimed in claim 1 or 2 in which the solenoid is a latching solenoid whereby no power is consumed when the locking member is in the first or second position.

4. The stretcher incorporating a wheel assembly as claimed in any preceding claim in which the solenoid is biased towards the locked position.

5. The stretcher incorporating a wheel assembly as claimed in claim 4 in which the locking member is caused to move against the bias when moving over the guide surface towards the opening.

6. The stretcher incorporating a wheel assembly as claimed in any preceding claim in which at least one guide surface is provided on the bracket.

7. The stretcher incorporating a wheel assembly as claimed in claim 6 in which the guide surface extends downwardly away from the opening.

8. The stretcher incorporating a wheel assembly as claimed in any of preceding claim in which at least one guide surface is provided on the locking member.

9. The stretcher incorporating a wheel assembly as claimed in any preceding claim in which the solenoid is activated from a region remote from the wheel assembly.

10. The stretcher incorporating a wheel assembly as claimed in claim 9 in which the solenoid is activated in the region of a handle for the stretcher.

11. A method of locking or unlocking a bracket of a wheel assembly on a stretcher in which the wheel assembly is in accordance with any preceding claim comprising causing the locking member to move between at least one of the positions by activating the solenoid and causing the locking member to move towards the locked position when the opening and locking member are not aligned and in which the locking member does not contact the bracket and then causing rotation of the bracket about the second axis to bring the locking member into contact with the bracket whereby contact with the guide surface of the bracket causes the locking member to move towards and then into the opening to prevent the bracket from rotating about the second axis thereby locking the bracket.

12. The method as claimed in claim 11 comprising activating the solenoid from a region remote from the wheel assembly.