GB2546085A

GB2546085A - Extending leg rest and method of deployment therefor

Info

Publication number: GB2546085A
Application number: GB1600275.0A
Authority: GB
Inventors: David John Scotford Timothy
Original assignee: Zodiac Seats UK Ltd
Current assignee: Safran Seats GB Ltd
Priority date: 2016-01-07
Filing date: 2016-01-07
Publication date: 2017-07-12
Anticipated expiration: 2036-01-07
Also published as: GB2546085B; GB201600275D0

Abstract

An aircraft seat (1, figure 1) comprising a leg rest 3 movable (e.g. pivotable) between a first and second positions. The legrest 3 comprises a main body 9 and an extension portion 7. The extension portion 7 is retracted when the leg rest 3 is in the first (e.g. vertical) position and extended when the leg rest 3 is in the second (e.g. horizontal or inclined) position. Movement of the leg rest 3 from the first position to the second position mechanically actuates the extension portion 7 into the extended position. The leg rest may comprise a spring 23 biasing the extension portion towards the retracted position. An elongate flexible connector, e.g. belt 11 may connect a seat connection point 21 and an inner body connection point 19 via a guide, e.g. pulley system 13. Alternatively, the flexible connector may be cable, chain or strap and the guide may be a pin, sheave or rotatable body. Movement of the leg rest from the first to the second position may subject the flexible connector 11 to a tensile load, pulling connection point 19 towards the guide 13, resulting in the extension portion 7 being driven out of the main body 9.

Description

Extending leg rest and method of deployment therefor

Field of the Invention

The present invention concerns a leg rest. More particularly, but not exclusively, this invention concerns a leg rest for an aircraft seat. The invention also concerns a method for deploying a leg rest.

Background of the Invention

Extending leg rests are an established feature of aircraft seats. Typically, extending leg rests are controlled by a plurality of electrical actuators, for example, a known extending leg rest employs a primary electrical actuator to rotate the leg rest and a secondary electrical actuator to deploy an extending portion. Electrical actuators found in aircraft seats are expensive, add weight, and require electrical connections to power and control them. Furthermore, actuators housed within moving elements can cause problems for the routing of the electrical harness used to control and drive the actuator. The harness must be long enough to reach the actuator in the extremes of the movement and must also be shielded from moving parts which may damage the harness during the movement.

The present invention seeks to mitigate the above-mentioned problems. Alternatively or additionally, the present invention seeks to provide an improved extending leg rest for an aircraft seat and method of deployment therefor.

Summary of the Invention

The present invention provides, according to a first aspect, an aircraft seat comprising a back rest, a seat pan, and a leg rest; the leg rest movable between a first position and a second position, the leg rest comprising a main body and an extension portion, the extension portion arranged to be in a retracted position when the leg rest is in the first position and an extended position when the leg rest is in the second position; wherein the movement of the leg rest from the first position to the second position mechanically actuates the extension portion into the extended position.

The movement of the leg rest from the first position to the second position may mechanically actuate the extension portion into an extended position via a mechanical actuating system. The leg rest may be associated with an electrically driven actuator for moving the leg rest between the first position and second position. Alternative actuators may include hydraulically or pneumatically driven actuators. The mechanical actuating system may operate without requiring any provision of an externally generated driving force, for example via electrically driven actuators, other than that of the leg rest moving between the first position and the second position. Advantageously, the invention may provide an aircraft seat with an extendible leg rest with a reduced number of electrical actuators. Such an arrangement may reduce the cost of the aircraft seat and/or reduce the complexity of the aircraft seat.

The present invention uses the motion of the leg rest from the first position to the second position to drive the extension portion out of the main body of the leg rest, thereby eliminating the need for a dedicated electrical actuator for this purpose. This arrangement may advantageously reduce the weight of the aircraft seat and/or the technical complexity associated with housing an actuator within a moving element. Furthermore a mechanical system may be more reliable and cheaper to implement than an electrical system.

The extension portion may be at least partially contained within the main body of the leg rest when the leg rest is in the first position. The extension portion may be fully contained within the main body of the leg rest when the leg rest is in the first position. The extension portion may at least partially extend out of the main body of the leg rest when the leg rest is in the second position. The extension portion may fully extend out of the main body of the leg rest when the leg rest is in the second position.

The back rest, seat pan, and leg rest may be mounted upon a chassis. The chassis may be arranged to be fixed to the floor of an aircraft.

The first position of the leg rest may correspond to a position in which the leg rest is in a substantially vertical position. The second position of the leg rest may correspond to a position in which the leg rest is in a substantially horizontal position. Such horizontal and vertical positions may be defined with respect to the orientation of the floor of an aircraft to which the aircraft seat is fixed. The second position of the leg rest may correspond to a position in which the leg rest is inclined at an angle between a vertical position and a horizontal position. The angle of inclination may be between 45 degrees and 90 degrees. The angle of inclination may be between 45 degrees and 70 degrees.

The angle of inclination may be between 45 degrees and 80 degrees. Such a position may commonly be found on aircraft seats which do not have a fully flat, bed position. Such aircraft seats may be referred to as Z-bed aircraft seats.

The first position may correspond to a position in which the leg rest is located between the underside of the seat pan and the floor of an aircraft cabin, such that a passenger may sit in the aircraft seat with their feet resting upon the floor of the aircraft cabin. The second position may be such that a passenger may sit in the aircraft seat with their legs resting upon the leg rest.

The aircraft seat may be a multi-position seat in which the back rest, seat pan, and leg rest are all movable relative to the chassis.

The aircraft seat may have a taxi, take-off and landing (TTL) position in which the back rest is upright and the leg rest is in the first position.

The aircraft seat may have a bed mode position in which the back rest is reclined, the seat pan is moved away from the back rest, and the leg rest is in the second position.

The leg rest may be pivotable between the first position and the second position. The leg rest may be pivotable between the first position and the second position about a point fixed with respect to the seat pan.

The extension portion may be arranged to be extendible out of the main body along an axis fixed with respect to the main body. The extension portion may be arranged to move between the retracted position and extended position with an approximately linear motion. Alternatively, the extension portion may be arranged to move between the retracted position and the extended position with an approximately curvilinear motion. The extension portion may move between the retracted position and the extended position with a non-linear motion.

An elongate flexible connector may connect a first point that is fixed with respect to the seat pan and/or chassis and a second point that is fixed with respect to the extension portion. The flexible connector may pass from the first point, around a guide that is mounted upon the main body of the leg rest, to the second point.

The direction in which the flexible connector extends may change as the flexible connector passes around the guide. The flexible connector may change direction at least once along its length. The flexible connector may have a radius of curvature. The minimum radius of curvature of the flexible connector, in use, may be at the guide. The minimum radius of curvature of the flexible connector, in use, may be substantially egual to the radius of the guide.

The flexible connector may comprise a length in a longitudinal direction, width in a transverse direction, and a thickness in a depth direction. The flexible connector may be substantially longer than it is wide.

The flexible connector may be substantially longer than it is thick.

The flexible connector may be sufficiently flexible to be folded back upon itself along a fold line spanning the width of the flexible connector. The flexible connector may be folded with a minimum radius of curvature of less than 100 mm. The flexible connector may be folded with a minimum radius of curvature of less than 50 mm.

The flexible connector may be sufficiently stiff to not exceed a longitudinal strain of 5 % in use. The flexible connector may be sufficiently stiff to not exceed a longitudinal strain of 2 % in use.

The flexible connector may be a belt, a cable, a chain, or a strap.

The guide may be a pulley, a sheave, or a body rotatably mounted upon an axle. The guide may be a fixed body. The guide may be a pin. The guide may have a radius of curvature.

Moving the leg rest between the first and second positions may result in the guide moving away from the first connection point. Moving the leg rest from the first position to the second position may subject the flexible connector to a tensile load. Moving the guide away from the first connection point may subject the flexible connector to a tensile load. Moving the leg rest from the first position to the second position may cause the flexible connector to pull the second connection point towards the guide.

When the leg rest is in the second position, the distance between the first connection point and the guide may be greater than when the leg rest is in the first position.

When the leg rest is in the second position, the distance between the second connection point and the guide may be less than when the leg rest is in the first position.

As the leg rest moves from the first position to the second position, the guide may move away from the first connection point. This may result in a load being introduced into the flexible connector, thereby causing the flexible connector to pull the second connection point closer to the guide. The extension portion may be driven out of the main body as the second connection point moves towards the guide.

The leg rest may comprise a biasing device arranged to bias the extension portion relative to the main body. The biasing device may be arranged to bias the extension portion towards the retracted position. The biasing device may connect the main body and the extension portion. Movement of the leg rest between the first and second positions may result in a force being applied to the biasing device. Movement of the leg rest from the first position to the second position may increase the force on the biasing device. The force may be applied, directly or indirectly, via the flexible connector. The force may be a tensile force. Movement of the leg rest from the second position to the first position may decrease the force on the biasing device. The force may urge the extension portion into retracted position.

Movement of the leg rest from the first position to the second position may cause the biasing device to extend. Movement of the leg rest from the second position to the first position may cause the biasing device to contract.

The biasing device may be arranged to move the extension portion into the main body as the leg rest is moved from the second position to the first position. The biasing device may be arranged to pull the extension portion into the main body as the leg rest is moved from the second position to the first position. The biasing device may comprise a spring.

According to a second aspect of the invention there is also provided a leg rest for an aircraft seat, the leg rest movable between a first position and a second position, the leg rest comprising a main body and an extension portion, the extension portion arranged to be in a retracted position when the leg rest is in the first position and an extended position when the leg rest is in the second position; wherein the movement of the leg rest from the first position to the second position mechanically actuates the extension portion into an extended position.

According to a third aspect of the invention there is also provided a method of operating a leg rest of an aircraft seat, the aircraft seat according to the first aspect of the invention; the method comprising the step of moving the leg rest from the first position to the second position.

The method may comprise the further step of moving the leg rest from the second position to the first position, thereby resulting in the extension portion moving from the extended position to the retracted position.

It will of course be appreciated that features described in relation to one aspect of the present invention may be incorporated into other aspects of the present invention. For example, the method of the invention may incorporate any of the features described with reference to the apparatus of the invention and vice versa.

Description of the Drawings

Embodiments of the present invention will now be described by way of example only with reference to the accompanying schematic drawings of which:

Figure 1 shows an isometric view of an aircraft seat comprising a leg rest according to a first embodiment of the invention;

Figure 2 shows a cross-sectional view of a leg rest according to the first embodiment of the invention in the stowed position;

Figure 3 shows a cross-sectional view of a leg rest according to the first embodiment of the invention in a partially deployed position; and

Figure 4 shows a cross-sectional view of a leg rest according to the first embodiment of the invention in a fully deployed position.

Detailed Description

An aircraft seat 1 comprising a leg rest 3 according to a first embodiment of the invention is shown in Figure 1. The aircraft seat further comprises a back rest 2 and a seat pan 4. The back rest 2, seat pan 4, and leg rest 3 are mounted upon a chassis (not shown in the figures) which is fixedly mounted upon the floor of an aircraft.

The aircraft seat 1 is a multi-position aircraft seat in which the back rest 2, seat pan 4, and leg rest 3 are all movable relative to the chassis. The aircraft seat 1 is movable between two extreme positions; a taxi, take-off, and landing (TTL) position and a bed mode position. In the TTL position, the back rest 2 is positioned upright and the leg rest 3 is stowed in a near vertical position in the space between the underside of the seat pan 4 and the floor of the aircraft cabin, such that a passenger may sit upright in the aircraft seat 1 with their feet resting upon the floor of the aircraft cabin.

In the bed mode position the back rest 2 is reclined, the seat pan 4 is moved away from the back rest 2, and the leg rest 3 is in a substantially horizontal position, such that a passenger may sit in a reclined position in the aircraft seat 1 with their legs resting upon the leg rest 3.

The leg rest 3 comprises an extension portion 7 and a main body 9, the extension portion 7 movable from a retracted position when the leg rest 3 is in the first position, to an extended position when the leg rest 3 is in the second position. The extension portion 7 is almost fully contained within the main body of the leg rest when the leg rest is in the first position, and when the leg rest is in the second position, the extension portion extends from the main body of the leg rest, thereby increasing the overall length of the leg rest 3.

The leg rest 3 is moveable between a first position, shown in Figures 1 and 2, in which the leg rest 3 is positioned approximately vertically such that a passenger may sit in the aircraft seat 1 with their feet positioned on the floor of the aircraft cabin, and a second position, shown in Figure 4, in which the leg rest 3 has pivoted about a pivot point 5 located at the edge of the seat pan 4, towards the horizontal plane, in which the leg rest 3 is approximately horizontal such that the passenger may sit in the aircraft seat 1 with their legs resting upon the leg rest 3. In alternative embodiments, for example with Z-bed aircraft seats, the second position may be such that the leg rest is inclined at an angle between the vertical and horizontal.

As can be seen in Figures 1 and 2, the overall length of the leg rest 3 is restricted by the space into which the leg rest 3 must fit whilst in the first position, which in this case is approximately equal to the distance between the underside of the seat pan 4 and the cabin floor. However, to provide optimum support to the legs of a passenger, it is preferable that the leg rest 3 may increase in overall length when the leg rest 3 is in the second position. Extension of the leg rest 3 when in the second, approximately horizontal, position is achieved by movement of the extension portion 7 from the retracted position to the extended position during movement of the leg rest 3 from the first position to the second position.

As can be seen in Figure 2, the leg rest 3 comprises an inner body 15 that is mounted upon a linear slide 17 within the main body 9. A first, lower, end of the inner body 15 forms the extension portion 7 which is arranged to extend out of the lower end of the main body 9 as the inner body 15 moves along the linear slide 17 in the direction of the arrow labelled W in Figure 3. When in the second position, as shown in Figure 4, the total length of the leg rest 3 is egual to the length of the extension portion 7 protruding from the end of the main body 9, plus the length of the main body 9.

During movement between the first position and second position, the extension portion 7 is driven out of the main body 9 by a belt 11 and pulley 13 system. With reference to Figures 2 to 4, a belt 11 passes from a seat connection point 21 located at the edge of the seat 1, around a pulley 13 mounted on the lower end of the main body 9, to an inner body connection 19 point located on the second, upper, end of the inner body 15. As the leg rest 3 is pivoted about the pivot point 5 in the direction of the arrow labelled X in Figure 3 the distance Y between the seat connection point 21 and the pulley 13 increases thereby causing the belt 11 to pull the inner body connection 19 point towards to the pulley 13. This movement results in the extension portion 7 extending by a distance Z out of the lower end of the main body 9. It should be noted that while a single belt 11 and pulley 13 system has been described here, the presently described embodiment of the invention comprises two such systems, one located at each side of the seat 1.

As shown schematically in Figures 3 and 4, the second, upper, end of the inner body 15 is connected to the inner surface of the main body 9 by a spring 23 such that when the leg rest 3 is being moved from the first position to the second position, the belt 11 and pulley 13 system is arranged to simultaneously drive the extension portion 7 out of the main body 9 and extend the spring 23. When moving the leg rest 3 from the second position back to the first position, as the tension in the belt reduces, the force imparted by the extended spring 23 on the inner body 15 retracts the extension portion 7 back into the main body 9.

Where in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, whilst of possible benefit in some embodiments of the invention, may not be desirable, and may therefore be absent, in other embodiments.

Claims

1. An aircraft seat comprising a back rest, a seat pan, and a leg rest; the leg rest movable between a first position and a second position, the leg rest comprising a main body and an extension portion, the extension portion arranged to be in a retracted position when the leg rest is in the first position and an extended position when the leg rest is in the second position; wherein the movement of the leg rest from the first position to the second position mechanically actuates the extension portion into the extended position.

2. An aircraft seat according to claim 1 wherein the first position of the leg rest corresponds to a position in which the leg rest is in a substantially vertical position and the second position of the leg rest corresponds to a position in which the leg rest is in a substantially horizontal position.

3. An aircraft seat according to claim 1, wherein the first position of the leg rest corresponds to a position in which the leg rest is in a substantially vertical positon and the second position of the leg rest corresponds to a position in which the leg rest is inclined at an angle between a vertical position and a horizontal position.

4. An aircraft seat according to any of claims 1 to 3 wherein the leg rest is pivotable between the first position and the second position.

5. An aircraft seat according to any preceding claim wherein the extension portion is arranged to be driven out of the main body along an axis fixed with respect to the main body.

6. An aircraft seat according to any preceding claim wherein an elongate flexible connector connects a first point that is fixed with respect to the seat pan and a second point that is fixed with respect to the extending portion.

7. An aircraft seat according to claim 6 wherein the flexible connector passes from the first point, around a guide that is mounted upon the main body of the leg rest, to the second point.

8. An aircraft seat according to claim 7 arranged such that movement of the guide away from the first connection point subjects the flexible connector to a tensile load.

9. An aircraft seat according to claim 7 or 8 arranged such that movement of the leg rest from the first position to the second position causes the flexible connector to pull the second connection point towards the guide .

10. An aircraft seat according to any of claims 7 to 9 wherein the extension portion is arranged to be driven out of the main body as the second connection point moves towards the guide.

11. An aircraft seat according to any preceding claim wherein the leg rest comprises a biasing device arranged to bias the extension portion relative to the main body.

12. An aircraft seat according to claim 11 wherein the biasing device is arranged to bias the extension portion towards the retracted position.

13. An aircraft seat according to claim 11 or 12 arranged such that movement of the leg rest between the first position and second position results in a force being applied to the biasing device.

14. An aircraft seat according to claim 13 arranged such that movement of the leg rest from the first position to the second position increases the force being applied to the biasing device.

15. An aircraft seat according to claim 13 or claim 14 arranged such that movement of the leg rest from the second position to the first position decreases the force on the biasing device.

16. An aircraft seat according to any of claims 11 to 15 wherein the biasing device is arranged to move the extension portion into the main body as the leg rest is moved from the second position to the first position.

17. A leg rest for an aircraft seat; the leg rest movable between a first position and a second position, the leg rest comprising a main body and an extension portion, the extension portion arranged to be in a retracted position when the leg rest is in the first position and an extended position when the leg rest is in the second position; wherein the movement of the leg rest from the first position to the second position mechanically actuates the extension portion into an extended position.

18. A method of operating a leg rest of an aircraft seat, the aircraft seat as claimed in claim 1, the method comprising the step of (i) moving the leg rest from the first position to the second position, thereby extending the extension portion into an extended position.

19. The method of claim 17 wherein the method comprises the further step of (ii) moving the leg rest from the second position to the first position, thereby moving from the extended position to the retracted position.

20. An aircraft seat substantially as herein described with reference to any of Figs. 1, 2, 3 and 4 of the accompanying drawings.

21. A leg rest substantially as herein described with reference to any of Figs. 1, 2, 3 and 4 of the accompanying drawings .

22. A method of extending a leg rest substantially as herein described with reference to any of Figs. 1, 2, 3 and 4 of the accompanying drawings.