GB2414172A - Footrest raising mechanism for a chair - Google Patents

Abstract

The invention relates to a foot rest raising mechanism that is connected to a chair frame 1 via pivotal connectors which, at their other end, are connected to a leg rest 2. A parallelogram linkage is provided whereby a footrest 3 can be raised forwards and upwards relative to and generally into alignment with the leg rest and, when not in use, the foot rest can be lowered and tucked away under the seat frame.

Description

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Improvements Relating to Chair Foot Rests Chairs are provided with adjustable leg rests which can be raised up and down. However, since the leg rest generally tends to be somewhat shorter than the length of the raised leg there is often the need to provide a separate attachable footrest. It is an object of this invention to provide a chair of this nature whereby the footrest can automatically be provided when a leg rest is raised.

Accordingly, there is provided a footrest raising mechanism for a chair, the chair having a frame to which are pivoted the one ends of connectors, which are in turn pivoted at their other ends to sidearms of a legrest, with the footrest having a pair of struts which are pivoted at their one ends to the lower end of the sidearms, with the other ends of the struts being pivoted to the one ends of a pair of linkages, the upper ends of the linkages being pivotally connected to the one ends of the connectors, the sidearms, linkages, connectors and struts defining a pair of parallelogram structures when the legrest is in a lowered position, with the struts positioned such that the footrest is tucked under the seat- frame, whilst rotation of the legrest upwardly to a raised position relative to the frame will create a cross-over of each sidearm with the associated linkage to realign the struts to cause the footrest to be moved forwards and upwards relative to and generally into alignment with the legrest.

In such a structure the footrest is tucked away below the seat frame during normal use and is only raised upwardly and into alignment with the leg rest when the leg rest itself is raised. The raising of the footrest is achieved by the interlinked side arms, linkages, connectors and struts moving first from the parallelogram array into a crossover condition which thus causes the footrest to be rotated as it is raised.

Ideally the connectors will be of arcuate form as this assists in the raising operation and the rotation of the footrest. Equally it is preferred that the ends of the side arms should essentially be of arcuate form to ensure that the sidearms are parallel to but offset from the line of the linkages.

In the preferred arrangement the footrest will have an extension portion rigidly mounted to the lower end of the footrest so that it can be brought into alignment with the legrest. The extension will ideally be spring-loaded into alternative retracted and extended conditions.

It is envisaged that the mechanism may incorporate a drive mechanism for moving the legrest between the lowered position and the raised position.

Such a drive mechanism could be a gas strut. This is particularly advantageous for chairs for handicapped persons.

The invention may be performed in various ways and a preferred example thereof will now be described, with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a side perspective view of part of a frame of a chair illustrating a leg rest and footrest raising structure of this invention; Figures 2 to 7 are generally similar views showing various stages of actuation of the mechanism illustrated in Figure 1; Figure 8 is a side view of the fully raised mechanism as shown in Figure 7; and Figure 9 illustrates a chair for handicapped persons incorporating the structure of Figure 1.

Part of a seat framework 1 of an adjustable chair is shown in Figure 1.

This is hingedly linked to a leg rest 2 and a footrest 3. Side arms 4 extend between the frame 1 and the footrest 3 to either side of the leg rest 2. At their upper ends, the side arms are pivotally connected at 5 to connectors 6. The other ends of these connectors are attached to the frame 1 at 7. Also, linkages 8 are pivotally connected at 7 to the frame 1. The other ends of the side arms 4 and linkages 8 are pivotally connected at respectively opposed ends of struts 9 at 10 and 11. The mid portions of the struts 9 are secured to the ends of a footrest frame 12. In the lowered position, as shown in Figure 1, the side arms 4 and linkages 8 form a parallelogram structure with the connectors 6 and struts 9.

When the side arms 4 are raised, by means of a gas strut 14 connected at point 13 (see Figure 8), the side arms and linkages are forced to move in a manner indicated by the successive steps of Figures 2 to 5 so that they move into a crossed over condition (as is particularly visible in Figure 4). This causes the footrest 3 to be raised generally into alignment with the seat frame 1. At the same time the struts 9 are rotated in such a way that the foot rest is moved from a position below and behind the leg rest 2 to the position indicated in Figure 5 where the foot rest is generally in alignment with the leg rest 2. An extension portion 15 (which can carry a padded support) is then rotated about a hinge 16 attached to the footrest frame 12 so as to move into alignment with the foot rest 3, as shown in Figures 6 and 7. The final condition is then illustrated in the side view of Figure 8.

This fully extended position can also be seen from the drawings of the complete chair assembly of Figure 9.

When the leg rest is to be lowered, by a reverse operation of the gas strut 14, the side arms and linkages will be rotated in the reverse operation so as to return the assembly to the condition as shown in Figure 1. During this process the extension member 15 will hit the floor and will be folded back towards the footrest 3. The hinge 16 is spring loaded into both the extended and retracted conditions so that, when the extension member is pushed upwardly upon contact with the ground it will snap back into the retracted condition as shown in Figures 1 to 5.

Claims (7)

1. A footrest raising mechanism for a chair, the chair having a frame to which are pivoted the one ends of connectors, which are in turn pivoted at their other ends to sidearms of a legrest, with the footrest having a pair of struts which are pivoted at their one ends to the lower end of the sidearms, with the other ends of the struts being pivoted to the one ends of a pair of linkages, the upper ends of the linkages being pivotally connected to the one ends of the connectors, the sidearms, linkages, connectors and struts defining a pair of parallelogram structures when the legrest is in a lowered position, with the struts tQ positioned such that the footrest is tucked under the seat-frame, whilst rotation . ë of the legrest upwardly to a raised position relative to the frame will create a .

cross-over of each sidearm with the associated linkage to realign the struts to ë cause the footrest to be moved forwards and upwards relative to and generally into alignment with the legrest. .

156

2. A mechanism according to claim 1, wherein the connectors are of arcuate form.

3. A mechanism according to claim 1 or claim 2, wherein the ends of the sidearms are essentially of arcuate form to ensure that the sidearms are parallel to but offset from the line of the linkages.

4. A mechanism according to any one of claims 1 to 3, wherein the footrest has an extension portion rigidly mounted to the lower end of the footrest so that it can be brought into alignment with the legrest.

5. A mechanism according to claim 4, wherein the extension is spring loaded into alternative retracted and extended conditions.

6. A mechanism according to any one of claims 1 to 5, including a drive mechanism for moving the legrest between the lowered position and the raised position.

7. A mechanism according to claim 6, wherein the drive mechanism is a gas strut. ë . e.e ë ë ë :. ë . ë e..