GB2334671A

GB2334671A - vehicle seat with back/seat relative position indicator

Info

Publication number: GB2334671A
Application number: GB9803923A
Authority: GB
Inventors: Robert Anthony Corrigall; Duncan James Taylor
Original assignee: MG Rover Group Ltd
Current assignee: MG Rover Group Ltd
Priority date: 1998-02-25
Filing date: 1998-02-25
Publication date: 1999-09-01
Anticipated expiration: 2018-02-25
Also published as: GB2334671B; GB9803923D0

Abstract

In vehicle front seating which allows the back squab to be reclined, the back squab can be reclined to positions which will not provide adequate support for the occupant during a collision. To overcome this problem, a motor vehicle seat arrangement is disclosed which indicates to the occupant of the seat when the seat base and back are in a safe relative position for driving. The arrangement comprises a seat base 1 with a back squab 2 pivotally mounted about a pivot cam 5. The pivot cam includes an indent 6 which is engaged by an indicator arm 4 such that the position of the end 7 of the the indicator arm indicates to the seat occupant the relative positions of the seat base and back. The indicator may produce an audible noise, or contact the occupant, or may operate an indicator device on the dashboard. The cam may have a deformable or frangible surface so that the user of the seat can set his own preferred position.

Description

A MOTOR VEHICLE SEAT ARRANGEMENT The present invention relates to a motor vehicle seat arrangement.

Most motor vehicles now include front seating which allows pivot adjustment between the seat base and a back squab in order to allow an occupant to adjust the seat arrangement to a desired orientation.

Furthermore, some seat arrangements allow the back squab to be sufficiently reclined that a comfortable sleep position is achieved.

It will be appreciated that, if the back squab is too reclined, there is inadequate support for the occupant during a collision and in particular a rear collision. Furthermore, any head whiplash effect is accentuated by the occupant position with such a reclined back squab and the extent of such head whiplash travel is increased by such a tilt orientation.

Recent developments with regard to motor vehicle safety have included incorporation of air bag mechanisms within seat arrangements such that the support frame for a back squab for the seat assembly is generally narrowed. Such narrow support frames do not allow occupant "sinking" as the occupant is pushed into the seat upon collision. It will be appreciated that typically a back squab of a motor vehicle seat arrangement includes a relatively large amount of padding/foam and traditionally an occupant has sunk into this padding or foam as the motor vehicle rapidly decelerates during a collision. Narrower support frames prevent or limit the depth of such occupant sinking upon collision and so the occupants torso remains more upright with an inherent increase in whiplash.

In view of the above, it is important that a motor vehicle is preferably only driven with the relative position between the base and the back squab in a safe configuration. It is an object of the present invention to provide a motor vehicle seat arrangement which substantially meets this objective.

In accordance with the present invention there is provided a motor vehicle seat arrangement comprising a seat base and a back squab pivotally secured together by a pivot cam including a bespoke indent indicative of relative position between said seat base and said back squab, said indent being engaged by indicator means representative of such relative position to an occupant of the seat arrangement.

The bespoke indent in the pivot cam may be indicative of unacceptable driving position or acceptable driving position or two or more bespoke indents may be provided within the pivot cam to indicate different relative positions between said seat base and said back squab.

The indicator means may be a lever arm with one, toothed, end engaging the indent whilst the other, indicator, end provides a representation of relative position to the occupant of the seat arrangement.

The indicative means may be spring biased into engagement with the pivot cam in order to ensure close correspondence between said indicator means and said pivot cam and good response to said bespoke indent.

It may be necessary to provide that a positive action is required to enable further pivotal movement about the pivot cam between the seat base and the back squab upon indication of a particular relative position between said seat base and said back squab. Such positive action may be to release the indicator means from engagement with the bespoke indent.

The pivot cam may include a deformable or frangible portion in which the bespoke indent position may be individually set, possibly through over movement of the indicator means, ie. lever arm. However, care must be taken that the indicator means is still representative of relative position between said seat base and said back squab.

The indicator means may provide an audio or visual representation of relative position attainment between the seat base and the back squab.

An embodiment of the present invention will now be described by way of example, only with reference to the accompanying drawing, in which: Figure 1 illustrates a seat assembly in schematic side elevation during pivotal movement; and Figure 2 illustrates the seat arrangement depicted in Figure 1 with an indicator element presenting an indication of relative position between a seat base and a back squab of the arrangement.

In the drawings, a seat base 1 is secured to a back squab 2 about a pivot hinge 3. Thus, the relative position between the base 1 and squab 2 can be altered through angular tilt in the direction of arrow heads A. Such tilting is generally conducted using a geared arrangement attached to the pivot hinge 3. Thus, an occupant of a seat comprising the base 1 and back squab 2 can adjust for comfort the relative position of the back squab 2. When the appropriate relative position is achieved, the pivot hinge 3 is no longer rotated and so that tilt orientation retained.

As indicated above, some relative positions between the seat base 1 and the back squab 2 are unsafe whilst driving. Thus, in accordance with the present invention, an indicator lever 4 acts about a pivot cam 5 which may, as depicted in the drawing, be a portion of the back squab 2 assembly or the pivot hinge 3. The pivot cam 5 includes a bespoke indent 6. This bespoke indent 6 is indicative of a relative position between the base 1 and back squab 2. The indicator arm 4 includes an indicator end 7 and a toothed end 8 pivoting about an arm pivot 9. Thus, the toothed end 8 is in sliding engagement with the pivot cam 5 until it encounters the bespoke indent 6 whereupon, through action about the arm pivot 9, the indicator end 7 alters its position. This alteration in an indicator end 7 position is indicative to an occupant of the seat arrangement, that the particular relative position between the base 1 and the back squab 2 has been attained. Such indication to the occupant of the seat arrangement may be through emission of an audible click, through appropriate electrical sensing to an indicator device on a dashboard of the motor vehicle or possibly as a result of a tactile action by the indicator end 7 upon the occupant.

Once the toothed end 8 engages the bespoke indent 6 it can be arranged, through suitable sloping of that indent 6, that further relative tilting between the base 1 and the back squab 2 is prohibited or that such rotation can continue.

Normally, the relative position between the base 1 and the back squab 2 indicated by the indicator arm 4 will be that at which an unacceptable seat arrangement configuration is present for driving a motor vehicle.

However, it will be appreciated that the indent 6 could alternatively provide an indication of the best relative position between the base 1 and the squab 2 for motor vehicle driving or lumbar/posture of the occupant. Thus, several indents could be provided in the pivot cam 5 for each of these relative positions between the base 1 and the back squab 2.

Inherently, there will be a conflict between the actual relative positions chosen by a motor vehicle seat arrangement manufacturer and those favoured by the motor vehicle user. Thus, the cam 5 may be provided with a frangible or deformable surface to allow individual formation of indents 6 in the cam 5 by the user of a seat arrangement. Thus, the lever arm 4 could allow, after appropriate configuration, excessive movement by pressure on the indicator end 7 such that the toothed end 8 creates an indent in the deformable or flangible surface of the cam 5. Thus, this individualised indent 6 would be retained within the cam 5 and upon normal operation of the indicator arm 4 such relative positions between the base 1 and the back squab 2 would be indicated by the indicator end 7.

It will be appreciated that most conveniently the indicator arm 4 must be kept in close engagement with the cam 5 surface. Thus, typically a spring bias may be provided about the pivot 9 to facilitate such engagement.

An alternative method of indicating to an occupant of a seat that a particular relative position between the base 1 and the squab 2 has been achieved is to prevent further relative pivoting about the pivot 3 unless a specific positive action is taken. Thus, the toothed end 8 will engage the indent 6 and so prevent further rotation about the pivot 3 either backwards or both forwards and backwards. In such circumstances, the occupant of the seat will realise that a particular relative position or orientation has been achieved by the seat arrangement and that further tilting will either precipitate an unsafe configuration for the seat arrangement or a configuration which is not recommended.

It is known that individual occupants have different requirements for seat arrangement configuration. However, an acceptable configuration is with the squab 2 at approximately 25"to a perpendicular through the pivot 3. As indicated above, such a relative position between the base 1 and the squab 2 may be indicated by the indicator end 7 and a specific positive action required to alter the relative relationship. An unacceptable configuration may be 35 to that perpendicular through the pivot 3.

Claims

CLAIMS 1. A motor vehicle seat arrangement comprising a seat base and a back squab pivotably secured together by a pivot cam including a bespoke indent indicative of relative position between said base and said back squab, said indent being engaged by indicator means representative of such relative position to an occupant of the seat arrangement.
2. An arrangement as claimed in Claim 1, wherein said indent provides a representative indication of an unacceptable driving position for an occupant of the seat arrangement within the motor vehicle.
3. An arrangement as claimed in Claim 1, wherein said bespoke indent provides a representative indication of an acceptable driving position for an occupant of the seat arrangement within the motor vehicle.
4. An arrangement as claimed in any preceding claim, wherein said indicator means comprises a lever arm pivotable relative to said pivot cam such that a toothed end engages the pivot cam and an indicator end is displaced as a result of engagement by said toothed end engaging said bespoke indent.
5. An arrangement as claimed in Claim 4, wherein said lever arm is biased into engagement with said pivot cam.
6. An arrangement as claimed in any preceding claim, wherein said indicator means is coupled within said arrangement such that a positive action must be effected by an occupant of the seat arrangement before further pivotal movement about said pivot cam between the base and the back squab is allowed.
7. An arrangement as claimed in any preceding claim, wherein at least a proportion of said pivot cam is deformable or frangible in order to allow individual bespoke indents to be provided by an occupant of the seat arrangement as required.
8. An arrangement as claimed in any preceding claim, wherein said pivot cam includes a plurality of bespoke indents respectively engageable by said indicator means.
9. A motor vehicle seat arrangement substantially as hereinbefore described with reference to the accompanying drawings.