GB2433432A

GB2433432A - Movable seat assembly for a vehicle

Info

Publication number: GB2433432A
Application number: GB0526392A
Authority: GB
Inventors: Kevan Hodgins
Original assignee: Virgin Atlantic Airways Ltd
Current assignee: Virgin Atlantic Airways Ltd
Priority date: 2005-12-23
Filing date: 2005-12-23
Publication date: 2007-06-27
Also published as: GB0526392D0

Abstract

A movable seat assembly for a vehicle, particularly an aircraft, has a seat back member (2) that latches into an upright position or a flat position for providing a bed surface. The seat back is unlatched for manual movement between the two positions by a short operation of a drive motor (22). The unlatched condition can also cause the seat back to move to a third position, being a short distance towards the flat position. The latching assembly can have recesses 38 and 40 on a quadrant 36 which engage a lock pin 32 for latching the seat back into position. The motor rotates a cam 24 that releases the lock pin from the recesses and a hook (30) that engages a pin 34 for moving the seat back a short distance.

Description

A MOVEABLE SEAT ASSEMBLY FOR A VEHICLE

The present invention relates to a moveable seat assembly for a vehicle of the type suitable for providing an upright seated position and a substantially flat resting position for a passenger. This type of seat is commonly used in an aircraft, in which passengers may require to sleep.

A conventional passenger seat for an aircraft comprises a seat pan and a backrest which can be pivoted rearwardly to recline, in some cases far enough to provide a substantially flat bed. The disadvantage of this is that a large pitch between adjacent rows of seats is required to in order to accommodate the full height of a passenger. Furthermore the surface provided by the backrest is not ideal for a bed, because the backrest is generally shaped for use as the seat whereas it is desirable for a bed to have a substantially flat surface.

W003/013903 discloses a passenger seat assembly wherein the backrest can be pivoted forwardly to a horizontal position, to form the bed surface in association with auxiliary elements in front of and behind the seat. Such seats can be arranged in a herringbone' design in an aircraft cabin to reduce the seat pitch. Furthermore the bed surface is formed by the opposite side of the backrest, which can therefore be a more suitable surface such as a flat surface.

This seat assembly uses a stepper motor to move a lever operatively connected to the backrest. The passenger uses a push button to activate the motor to move the backrest between the two positions. However, a fairly large and heavy motor mechanism is required to perform this movement. Furthermore the user has to wait while the motor travel is completed. This has resulted in users forcing the mechanism and damaging it.

According to the present invention there is provided a moveable seat assembly for a vehicle comprising: a seat back having a first position for providing a backrest to a seated passenger, and a second position for providing a substantially flat bed surface for the passenger; a latching assembly operatively connected to the seat back and having a first latched condition in which the seat back is secured in the first position thereof, a second latched condition in which the seat back is secured in the second position thereof, and an unlatched condition in which movement of the seat back between the first and second positions thereof is allowed; and a drive motor for the latching assembly; in which movement of the seat back into the first or second position causes the latching assembly to adopt the first or second latched condition respectively, and in which operation of the motor causes the latching assembly to adopt the unlatched condition.

Thus following a short actuation of the motor, the seat back is freed and the passenger may move it from one of the seat or bed positions to the other, where it will be securely latched until the motor is actuated again. Since the motor is only required to move relatively small components of the latching assembly, and not the seat back itself, a smaller and lighter mechanism may be used. Also, this avoids the need for the passenger to wait for the motor to complete the seat movement.

Preferably when the seat back is in the first position, further operation of the motor following adoption of the unlatched condition causes the seat back to move a short distance towards the second position. This provides a visual indication that the seat back is unlatched, and assists the passenger in being able to grip the upright seat back to move it to the second position.

The latching assembly may comprise first and second latching members biased towards mutual engagement to provide the first or second latched conditions, operation of the motor causing movement against the bias. The first latching member may be operatively connected to the seat back for movement therewith, and the second latching member may be operatively connected to the drive motor for movement therewith.

For example, the first latching member may include first and second detents and the second latching member may be biased towards engagement with the respective detents. Operation of the motor may cause movement of the second latching member away from the first latching member, out of engagement with the respective detent. Conveniently, the second latching member is operatively associated with drive motor by mean of a cam member and a cam follower to cause the movement away from the first latching member.

In order that the invention may be more readily understood, reference will now be made to the accompanying drawings, in which: Figure 1 is a schematic side view showing superimposed elements of the seat assembly with the seat back in the first position; Figure 2 is a schematic side view of the seat assembly of Figure 1 with the seat back in the second position; Figure 3 is a perspective view of part of a supporting structure of such a moveable seat assembly, showing the latching assembly and the drive motor according to one embodiment of the invention; Figure 4 is an enlarged perspective view of the latching assembly and drive motor of Figure 3; Figures 5 to 10 are side views of the latching assembly of Figure 4 in various different positions.

Referring to Figure 1, the seat assembly comprises a seat back 2 shown in a first position in which it is upright and a first side 3 of which provides a backrest of a seat for a passenger, the seat assembly further including a seat pan 4. As shown in Figure 2, the seat back 2 may be folded forwardly to assume a second position in which it is substantially horizontal, and in which the seat pan 4 is lowered. In this position, a second side 5 of the seat back 2 opposite the first side is aligned with an ottoman unit 6 in front of the seat, and a surface 8 behind the seat, to provide a substantially flat bed surface.

Referring also to Figure 3, the seat back 2 and the seat pan 4 are each connected to a pair of rockable side plates 10 for facilitating and guiding movement of the seat back and the seat pan between the first and second positions thereof. The side plates 10 may also facilitate and guide reclining movement of the seat back relative to the seat pan. One of the side plates 10 has a nose 11 on the lower edge thereof which is connected via a linkage 12 to a latch lever 14 forming part of a latching assembly 18. The latch lever 14 is mounted on a rotatable spline shaft 16 extending between the side plates 10.

It can be seen from Figure 3 that the latching assembly 18 is mounted on a strut 19 by mounting brackets 17. The strut 19 extends between a pair of side support plates 20 for supporting the seat assembly on the floor of the vehicle via legs 21. The side plates 10 are mounted for rocking movement relative to the support plates 20 about a pair of trunnions 13.

As shown more clearly in Figure 4, the latching assembly 18 has a drive motor within a housing 22. The motor is operable to rotate a cam 24 about a longitudinal motor drive axis 25 (see also Figures 5 to 10). A cam follower 26 is located at the lower end of a lock lever 28. The lock lever is mounted for pivotable movement at a midpoint 29 thereof between a pair of mounting plates 31. The other end of the lock lever 28 is pivotally attached to a serving hook by a lock pin 32.

The hook 30 is engagable with a serving pin 34 extending from a side surface of a quadrant 36. The quadrant 36 also includes two spaced detents in the form of recesses 38, 40 adjacent each end of an arcuate edge 37 thereof.

The lock pin 32 may ride over this edge and locate in one of the recesses 38, to provide the first and second latched positions of the seat back respectively. The quadrant 36 is mounted for rotation on the spline shaft 16 with the latching lever 14. Thus the quadrant 36 and the lock pin 32 form first and second latching members respectively.

Figure 5 shows the position of the latching assembly when the seat back is secured in the first or upright position. As can be seen from Figure 1, the latching lever 14 is in a substantially horizontal orientation (note that these Figures show the latching assembly in mirror image) and is secured by the lock pin 32 engaging the first recess 40 in the arcuate edge 37 of the quadrant 36.

The cam 24 is in the start position.

Upon actuation of the motor, the cam 24 turns in the clockwise direction about the axis 25. Referring to Figure 6, this causes the cam follower 26 to move to the right in the Figure. Thus the lock lever 28 rocks about the midpoint 29 such that the upper end moves to the left in the Figure. This causes the lock pin 32 to move out of the recess 40 and unlatch the quadrant 36, and free the lever 14 (and thus the seat back). Also the hook 30 engages with the serving pin 34 of the quadrant 36.

Referring now to Figure 7, further clockwise movement of the cam 24 causes the continuation of the rocking movement of the lever 28, such that the engagement of the hook 30 with the serving pin 34 moves the quadrant 36 in an anticlockwise direction, turning the spline shaft 16. This turning movement of the shaft 16 lifts the latching lever 14.

Referring again to Figures 1 and 2, the lifting movement of the latch lever 14 clockwise on the shaft 16 lifts the linkage 12, pulling the nose 11 of the side plate rearwardly. This causes the side plates 10 to turn in an anticlockwise direction about the trunnions 13 moving the seat back forwardly.

The seat back 2 then adopts a served position, as partially shown in broken lines in Figure 1, and is unlatched and free to move. The mechanism then resets, by the motor turning in the opposite direction, thus returning the cam 24 to the start position, as shown in Figure 8, and the hook 30 disengages from the serving pin 34. The passenger may then grasp the seat back 2 and swing it down into the horizontal bed position shown in Figure 2.

Referring to Figure 9, movement of the seat back to the bed position causes the lever 14 to turn anticlockwise with the spline shaft 16, such that the lock pin 32 rides along the arcuate edge of the turning quadrant 36. Upon the seat back reaching the flat bed position, the lock pin 32 rides over the corner of the arcuate edge 37 of the quadrant 36 and locates in the second recess 38 to secure the seat back 2 in the bed position.

When the motor is actuated in this position of the latch assembly, the cam 24 once again moves in a clockwise direction, and the lock lever 28 rocks in the anticlockwise direction. It can be seen from Figure 10 that this movement releases the lock pin 32 from the recess 38 to unlatch the seat back.

Therefore the latching lever 14 is once again free to move. The mechanism resets again, with the motor turning in the opposite direction to return the cam 24 to the start position. A passenger may then simply flip the seat back 2 back into the upright seat position, with the mechanism once again adopting the start position shown in Figure 5.

Claims

CLAIMS

1. A movable seat assembly for a vehicle comprising: a seat back having a first position for providing a backrest to a passenger sitting in the seat, and a second position for providing a substantially flat bed surface for the passenger; a latching assembly having a first latched condition in which the seat back is secured in the first position thereof, a second latched condition in which the seat back is secured in the second position thereof, and an unlatched condition in which movement of the seat back between the first and second position thereof is allowed; and a drive motor for the latching assembly; in which movement of the seat back into the first or second position causes the latching assembly to adopt the first or second latched condition respectively, and in which operation of the motor causes the latching assembly to adopt the unlatched condition.

2. A moveable seat assembly as claimed in claim 1, in which, when the seat back is in the first position, further operation of the motor following adoption of the unlatched condition causes the seat back to move to a third position, being a short distance towards the second position.

3. A moveable seat assembly as claimed in claim 1 or 2, in which the latching assembly comprises first and second latching members biased towards mutual engagement to provide the first or second latched conditions, operation of the motor causing movement against the bias.

4. A moveable seat assembly as claimed in claim 3, in which the first latching member comprises first and second detents, and the second latching member is biased towards engagement with the detents.

5. A moveable seat assembly as claimed in claim 3 or 4, in which the first latching member is operatively connected to the seat back for movement therewith, and the second latching member is operatively associated with to the drive motor for movement therewith.

6. A moveable seat assembly as claimed in claim 5, in which the second latching member is operatively associated with drive motor by means of a cam member and a cam follower.

7. A moveable seat assembly as claimed in any one of claims 3 to 6, in which the second latching member is engagable with the first latching member to cause movement of the first latching member from a position corresponding to the first position of the seat back to a position corresponding to the third position thereof.

8. A moveable seat assembly substantially as described herein with reference to the accompanying drawings.