GB2459696A - Multifunctional seat for a motor vehicle - Google Patents

Abstract

A motor vehicle multifunctional seat 14 comprises a seat cushion 20 and a seat back 22 defining an angle between, a mechanism 23, 24 to permit the seat to move transitionally relative to the vehicle (Figs. 8, 9), a mechanism to permit the seat back to fold flat upon the seat cushion (Fig. 7), a mechanism to permit the seat back to be reclined by increasing the angle between the seat back and the seat cushion (Fig. 10), and a mechanism 23, 26, 27, 28, 29, 36 to permit the seat to be tilted forward to improve access to an area behind the seat (Fig. 5). When the seat is titled forward, the mechanism automatically increases the angle between the seat cushion and the seat back. Latches may be provided to selectively hold the seat in each configuration. Also disclosed is a motor vehicle having at least one such multifunctional seat.

Description

A Multifunctional Seat for a Motor Vehicle The present invention relates to a seat for use in a vehicle and in particular to a multifunctional seat that can be translationally moved, reclined, folded flat and tilted forward to allow ingress and egress to portions of the motor vehicle located behind the location of the seat.

The second and third rows of seats in vehicles such as sport utility vehicles, minivans and crossover vehicles work best if they are multi-functional. Such second and third row seats are typically configured to fold flat to increase cargo carrying capability. Also, the second row of seats must fold forward so as to allow access to the third row of seats. Automotive designers have incorporated a number of different mechanisms to accomplish these desired multi-functions. Such mechanisms have, however, been complicated and, in many cases, counterintuitive for the vehicle operator.

It is an object of the invention to provide a multifunctional seat that solves problems associated with known seats by providing a cost effective and easily employed mechanism in a seat which is movable translationally, which may be folded flat, which may be reclined and which may be tilted forward to allow ingress or egress to seating rows and/or storage space behind the location at which the seat is mounted.

According to a first aspect of the invention there is provided a motor vehicle multifunctional seat comprising a seat cushion, a seat back arranged at a rear end of the seat cushion so as to define an included angle between the seat cushion and the seat back, a mechanism to permit the seat to translationally move relative to the motor vehicle to which the seat is fitted, a mechanism to permit the seat back to fold flat upon the seat cushion, a mechanism to permit the seat back to be reclined by increasing the included angle between the seat back and the seat cushion and a mechanism to permit the seat to be tilted forward to improve access to an area located to the rear of the seat wherein, when the seat is tilted forward to improve access, the respective mechanism is operable to automatically increase the included angle between the seat cushion and the backrest so as to enable the seat back to be moved further forward than it At least one component is shared by two or more of the mechanisms for reclining the seat, tilting forward the seat, folding flat the seat and translationally moving the seat.

The seat back may be pivotally connected at a lower end to a seat support structure for rotation about a first transverse axis to permit the included angle between the seat cushion and the seat back to be varied, the seat support structure may be pivotally connected at a front end to the motor vehicle for rotation about a second transverse axis and is selectively latchable at a rear end by a rear latch to the motor vehicle, the seat support structure may form with three other links a four bar linkage used to increase the angle between the seat cushion and the seat back when the seat is tilted forward by unlatching the rear latch and rotating the seat support structure about the second axis.

The three other links may be a first control link pivotally supported at a first end for rotation about the second pivot axis, a second control link pivotally connected at one end to a second end of the first control link and a third link pivotally connected at one end at a position offset from the first transverse axis to a second end of the second control link and connected to the seat back so as to be rotatable therewith about the first transverse axis.

A front latch may be provided to selectively hold the first control link in a predetermined position and the seat is moveable to the tilted forward position by releasing the rear latch while maintaining the front latch in a latched state so as to hold the first link in the predetermined position and moving the seat back forward so that the support structure rotates about the second pivot axis.

The seat back may be pivotally connected at a lower end to a seat support structure for rotation about a first transverse axis to permit the included angle between the seat cushion and the seat back to be varied, the seat support structure may form with three other links a four bar linkage, the three other links may comprise a first control link pivotally supported at a first end for rotation about a second pivot axis located at the front end of the support structure, a second control link pivotally connected at one end to a second end of the first control link and a third link pivotally connected at one end at a position offset from the first transverse axis to a second end of the second control link and connected to the seat back so as to be rotatable therewith about the first transverse axis and to recline the seat back a front latch used to selectively hold the first control link in a predetermined position may be released thereby allowing the first link to rotate about the second axis as the included angle between the seat cushion and the seat back is increased.

A rotary actuator may be interposed between the third link and the seat support structure to alter the included angle.

The seat back may be connected at a lower end by a support arm to a seat support structure for rotation about a first transverse axis, the seat back may be pivotally connected at a lower end to the support arm for rotation about a transverse fold axis offset from the first transverse axis, a first control arm may be pivotally connected at a first end to the seat support structure, a second control arm may be pivotally connected at a first end to a second end of the first control arm and may be pivotally connected at a second end to the seat back such that a lower portion of the seat back forms in combination with the support arm and the first and second control arms a four bar linkage, the seat cushion may be pivotally connected near to a front end to a first end of a forward leaning support leg, a second end of the support leg may be pivotally connected to the seat support structure, a rear end of the seat cushion may be pivotally connected to the second control arm so as to form in combination with the first control arm a five bar linkage and the four bar linkage in combination with the five bar linkage may be arranged to automatically lower the seat cushion as the seat back is folded forward about the transverse fold axis.

A latch may be provided between the seat back and the support arm to prevent relative rotation therebetween and the latch may be released to permit the seat back to be folded flat upon the seat cushion.

The seat support structure may comprise an upper support structure to which the seat cushion and the seat back are connected and a lower support structure pivotally connected at a front end to the motor vehicle and having a latch at a rear end to selectively prevent rotation of the seat support structure about the front end of the lower support structure and the upper support structure may be slidingly connected to the lower seat support structure so as to permit the seat to be translationally adjusted relative to the motor vehicle.

The front latch may be released to permit rotation of the first control link when the translational position of the seat is being adjusted.

According to a second aspect of the invention there is provided a motor vehicle having at least one multifunctional seat constructed in accordance with said first aspect of the invention.

The motor vehicle may have two outboard multifunctional seats and a central folding seat.

The multifunctional seat may be a second row seat for a motor vehicle having three rows of seats.

The invention will now be described by way of example with reference to the accompanying drawing of which:-Fig.l is a cutaway side view of a motor vehicle according to one aspect of the invention having three rows of seats; Fig.2 is a pictorial view of a multifunctional seat according to the invention showing the seat in a normal in use position; Fig.3 is a pictorial view of the seat shown in Fig.2 but showing the seat in a partially folded flat position; Fig.4 is a left hand side view of the seat shown in Figs.2 and 3 showing the seat in the normal seating position shown in Fig.2; Fig.5 is a left hand side view of the seat shown in Figs.2 and 3 showing the seat in a tilted forward position to provide maximum access to an area located to the rear of the seat; Fig.6 is a left hand side view of the seat shown in Figs.2 and 3 showing the seat in the partially folded flat position of Fig.3 Fig.7 is a left hand side view of the seat shown in Figs.2 and 3 showing the seat in a fully folded flat position; Fig.8 is a left hand side view of the seat shown in Figs.2 and 3 showing the seat in a rear position; Fig.9 is a left hand side view of the seat shown in Figs.2 and 3 showing the seat in a forward position; and Fig.10 is a left hand side view of the seat shown in Figs.2 and 3 showing the seat in a reclined position.

With particular reference to Fig.1 there is shown a two box motor vehicle 10 having an engine compartment 5 and a passenger compartment 6 in which is mounted three rows of seating 12, 14 and 16. The passenger compartment 6 is defined by a front wall 7, a rear wall 8, a roof structure 9, two side walls and a floor structure 13 which is stepped upwardly towards the rear of the vehicle 10.

The three rows of seating 12, 14, 16 comprise a first row of seats 12 mounted at the front of the passenger compartment and including the driving position for the vehicle 10, a second row seats 14 mounted to the rear of the first row of seats 12 a sufficient distance to enable adults to sit comfortably and a third row of seats 16 mounted to the rear of the second row of seats 14 a sufficient distance that either adults or children can sit comfortably.

The second row seating comprises of two outboard mounted multifunctional seat assemblies 14 constructed in accordance with this invention and a centre folding seat assembly that can fold flat but cannot tip forward. However it will be appreciated that all three of the seat assemblies could be multifunctional seat assemblies or only one of the outboard seats could be a multifunctional seat assembly.

A luggage compartment 11 is located within the passenger compartment 6 to the rear of the third row of seats 16.

Referring now to Figs.2 to 10 there is shown the multifunctional seat 14 in greater detail.

The multifunctional seat 14 comprises of a seat cushion and a seat back 22 which are arranged with respect to one another so as to define an included angle e (see Fig.4) A mechanism in the form of a two part seat support structure having lower and upper parts 23 and 24 is provided to permit the seat 14 to translationally move relative to the motor vehicle 10. A second mechanism in the form of interconnected four and five bar linkages is provided to permit the seat back 22 to told flat upon the seat cushion 20, a mechanism including a rotary actuator (not shown) is provided to permit the seat back 22 to be reclined by increasing the included angle e between the seat back 22 and the seat cushion 20 and a mechanism having a four bar linkage is provided to permit the seat 14 to be tilted forward to improve access to an area located to the rear of the seat 14 such as for example one of the third row of seats 16.

One of the advantages of the invention is that the four mechanisms referred to above are not distinct parallel mechanisms but share some components so as to reduce weight, cost and the complexity of the seat 14.

It will be appreciated that the mechanisms used to provide the functionality of the seat 14 are duplicated on each side of the seat 14 but for simplicity of understanding only the mechanisms located on one side of the seat 14 will be described in detail. Furthermore, the term transverse shall mean herein extending from a left side of the seat to a right side of the seat or vice-versa and the term translationally move' shall mean movement in a fore-aft direction with respec to the motor vehicle 10.

Referring first to the mechanism used to translationally move the seat 14, Fig.8 shows the seat 14 in a rear position and Fig.9 shows the seat 14 in a forward position.

The mechanism comprises of the upper support structure 24 to which the seat cushion 20 and the seat back 22 are connected and the lower support structure 23 which is pivotally connected at a front end to the floor 13 of the motor vehicle 10 for rotation about a tilt axis X-X. A latch 30 is attached to a rear end of the lower support structure 23 to selectively prevent rotation of the seat support structure about the front end of the lower support structure 23.

The upper support structure 24 is slidingly connected to the lower seat support structure 23 so as to permit the seat 14 to be translationally adjusted relative to the motor vehicle 10. It will be appreciated that latching means (not shown) is provided to hold the upper support structure 24 relative to the lower support structure 23. In this case the latching means is formed by a front latch (not shown) used to hold a first control link 26 from rotation by cooperating with a transversely extending rod 25 to which the first control link 26 is fastened but in other embodiments a separate latching means could be used. It should be noted that the first control link 26 forms part of the mechanism used to provide tipping forward of the seat 14 described below. Because one end of the first control link 26 is connected to the lower support structure 23 and the other end is connected by second and third control links 27 and 28 to the upper support structure 24 the first control link 26 must be allowed to rotate during translational adjustment of the seat 14.

Referring now to the mechanism used to effect forward tilting of the seat 14.

The seat back 22 is pivotally connected at a lower end to the upper support structure 24 by a support arm 29 for rotation about a recline or first transverse axis Y-Y to permit the included angle e between the seat cushion 20 and the seat back 20 to be varied.

As before, the lower support structure 23 is pivotally connected at a front end to the floor 13 of the motor vehicle 10 for rotation about the tilt axis X-X (this forms a second transverse axis or second pivot axis) and is selectively latchable at a rear end by the rear latch 30 to the floor of the motor vehicle 10.

The upper support structure 24 forms with three other links 26, 27 and 28 a four bar linkage used to increase the angle 8 between the seat cushion 20 and the seat back 22 when the seat 14 is tilted forward by unlatching the rear latch 30 and rotating the seat support structure about the second axis X-X.

The three other links are the first control link 26 pivotally supported at a first end by the transversely extending rod 25 for rotation about the second pivot axis X-X, the second control link 27 pivotally connected at one end to a second end of the first control link 26 and the third control link 28 pivotally connected at one end at a position offset from the first transverse axis Y-Y to a second end of the second control link 27 and connected to the seat back 22 -10 -via the support arm 29 so as to be rotatable therewith about the first transverse axis or first pivot axis Y-Y.

The front latch is used to selectively hold the first control link 26 in one or more predetermined positions.

The third control link 28 is fastened in this case to a pivot pin (not shown) at an opposite end to the end where it is connected to the second control link 27 and the support arm 29 is also fastened to the pivot pin. The pivot pin is rotatably supported by the upper support structure 24 by one or more bearings (not shown) . In other embodiments a rotary actuator (not shown), such as that shown for example in US 2007/0085399, may be interposed between the third control arm 28 and the upper support structure 24.

The seat 14 is moveable to the tilted forward position by releasing the rear latch 30 while maintaining the front latch in a latched state so as to hold the first link 26 in a predetermined position and then moving the seat back 22 forward so that the seat support structure comprising the upper and lower support structures 24 and 23 rotates about the second pivot axis X-X.

Fig.4 shows the seat 14 in a normal seating position and Fig.5 shows the seat 14 in its tipped forward position.

It will be noted that, because the position of the pivotal connection of the second control link 27 to the first control link 26 is located to the rear of the second pivot axis X-X and the radius from the second pivot axis X-X to the first pivot axis Y-Y is greater than the length of the second control link 27, when the pivot position of the second control link 27 to the third control link 28 passes by a location vertically above the position of the pivotal connection of the second control link 27 to the first control link 26 the seat back 22 must rotate in a clockwise direction as viewed in Figs.4 and 5 because the distance -11 -between the position of pivotal attachment of the second control link 27 to the third control link 28 and the first pivot axis Y-Y is constant whereas the paths of the first pivot axis Y-Y and the position of pivotal attachment of the second control link 27 to the third control link 28 are diverging.

Referring now to the mechanism used to effect flat folding of the seat 14, Fig.4 shows the seat 14 in a normal position, Fig.6 shows the seat 14 in a partially folded position and Fig.7 shows the seat 14 folded flat.

As before, the seat back 22 is connected at a lower end by the support arm 29 to the upper support structure 24 for rotation about the first pivot axis Y-Y. The seat back 22 is also pivotally connected at a lower end to the support arm 29 for rotation about a transverse fold axis Z-Z offset upwardly from the first pivot axis Y-Y.

A first control arm 31 is pivotally connected at a first end to the upper support structure 24 and a second control arm 32 is pivotally connected at a first end to a second end of the first control arm 31 and is pivotally connected at a second end to the seat back 22 such that a lower portion of the seat back 22 forms in combination with the support arm 29 and the first and second control arms 31 and 32 a four bar linkage.

The seat cushion 20 has a frame 19 and is pivotally connected near to a front end to a first end of a forward leaning support leg 36. The forward leaning support leg 36 is attached to a transversely extending rod 35 pivotally supported at each end by the upper support structure 24. A rear end of the seat cushion 20 (in practice the frame 19) is pivotally connected to the second control arm 32 so as to form in combination with the first control arm 31 a five bar linkage comprising the forward leaning support leg 36, the -12 -seat cushion 20, the first and second control arms 31 and 32 and the upper support structure 24.

The four bar linkage in combination with the five bar linkage is arranged to automatically lower the seat cushion as the seat back 22 is folded forward about the transverse fold axis Z-Z. This is due to the fact that the seat cushion 20 is connected to the seat back 22 by the second control arm 32 and the front support leg 36 leans forward. Therefore when the seat back 22 is folded forward about the fold axis Z-Z the rear end of the seat cushion 20 is lowered by the action of the second control arm 32 but because the folding motion of the seat back 22 also displaces the position of connection of the seat cushion 20 to the second control arm 32 forwards the whole seat cushion must move forwards. Because of the forward inclination of the support leg 36 any forward movement of the seat cushion 20 will cause the front of the seat cushion 20 to be lowered as the support leg 36 rotates about its lower end.

It will be appreciated that the lowering of the seat cushion 20 in this manner has several advantages. Two of these advantages are that it allows the use of a thicker seat cushion than would otherwise be possible thereby improving occupant comfort and allows the folded height of the seat 14 to be lower than would otherwise be possible.

In order to prevent the seat back 22 folding forward during normal use of the seat 14 a latching means (not shown) is provided between one of the first and second control arms 31 and 32, the seat back 22 and the support arm 29, the first control arm 31 and the support arm 29 and the first control arm 31 and the upper support structure 24.

Irrespective of the type or location of the latching means the latch is released to permit the seat back 22 to be folded flat upon the seat cushion 20 as shown in Fig.7.

-13 -Referring now to the mechanism used to effect flat folding of the seat 14, Fig.4 shows the seat 14 in a normal position and Fig.10 shows the seat 14 in a reclined position in which the included angle e between the seat cushion 20 and the seat back 22 has been increased.

The seat 14 is as previously described and the first, second and third control links 26, 27 and 28 are used in this case to control the recline angle of the seat back 22.

To recline the seat back 22 the front latch used to selectively hold the first control link 26 in a predetermined position is released thereby allowing the first link 26 to rotate about the second axis X-X and the included angle e between the seat cushion 20 and the seat back 22 is increased by applying pressure to the seat back 22. This will cause the seat back 22 to rotate in a clockwise direction as viewed in Figs.4 and 10.

Therefore as noted above part of the mechanism for the tilt forward mechanism is also used in this mechanism thereby reducing cost and complexity.

It will be appreciated that the first support arm 26 may be latchable in several predetermined positions. For example the front latch used to prevent rotation of the first control link 26 may be a friction brake device that can hold the first control link in a plurality of positions and may include a detent defined position.

Alternatively, the transversely extending rod 25 to which the first control link 26 is fastened may have a toothed wheel fastened thereto and a retractable member may be selectively engageable with the toothed wheel to hold the first control arm 26 in one of a number of predefined positions.

-14 -Instead of manually pushing the seat back 22 into a reclined position or pulling it back into a less reclined position a rotary actuator (not shown but referred to above) may be interposed between the third link 28 and the upper support structure 24 to alter the included angle e.

Therefore in summary, the invention provides a

multifunctional seat that provides improved access. By sharing components the cost and complexity of the seat is reduced.

It will be appreciated by those skilled in the art that although the invention has been described by way of example with reference to one or more embodiments it is not limited to the disclosed embodiments and that one or more modifications to the disclosed embodiments or alternative embodiments could be constructed without departing from the scope of the invention as set out in the appended claims.