Motor vehicle seat

ES 2 306 972 T3

DESCRIPTION

Automobile vehicle seat.

The present invention relates to a motor vehicle seat.

In certain types of vehicles, the seats have a structure that allows them to be concealed on the ground.

To this end, some armchairs provide that the backrest can be folded against the seat and, simultaneously, the seat, made up of a deformable parallelogram, is flattened on the floor.

In this configuration, the armchair has a smaller volume than when it is in a configuration in which the backrest is substantially vertical to the seat. This allows the vehicle's cargo volume to be increased as needed without having to remove the seats from the vehicle.

This type of seat finds its full interest in the case of the so-called rank 2 or rank 3 seat, that is, seats for rear passengers. When these seats are retracted, the cargo volume at the rear of the vehicle is considerably increased without having to remove them from the vehicle.

These retractable seats by folding back the backrest also have a function that allows them to be moved longitudinally with respect to the floor of the vehicle. This longitudinal movement is carried out by sliding on rails present on the ground.

Due to the longitudinal mobility of the seats, when they are retracted, it happens that, within a row of several seats (typically a row of three seats), each seat that belongs to this row is in a particular position with respect to down. In other words, each seat is retracted in the longitudinal position in which it was located. Consequently, within a row of seats, these in the retracted position may not be aligned in the transverse position of the vehicle.

Now, this is totally detrimental to the good geometry of the cargo space that is left by the recessed seats since this space then presents irregular contours due to misalignment in the transverse direction of the recessed seats.

Document FR-A-2 799 702 describes an armchair that has an articulation arm of which one end slides on a rail that has a port. This articulation arm causes a rearward displacement of the chair when its folding takes place, but the mechanical principle of sliding in a port induces friction, noise and, finally, a significant risk of the arm getting stuck.

An objective of the invention is therefore to propose a longitudinally adjustable vehicle seat which, when retracted, occupies a predetermined position with respect to the vehicle floor, and this, with great operational reliability.

The object of the invention is an armchair that can be placed on a structure of a motor vehicle, which has a seat on which a backrest is articulated in rotation, and is movable in translation with respect to the structure of the vehicle.

The seat comprises a seat positioning mechanism attached, on the one hand, to the seat and, on the other hand, to the vehicle structure that allows the seat to be moved to a predetermined location of the vehicle structure when the rotation of the vehicle takes place. backrest towards the seat, said mechanism comprising:

- a so-called transmission connecting rod joined at one of its ends in rotation to the backrest, and

- a so-called support connecting rod, with one of its ends, connected in rotation to the vehicle structure, these two connecting rods being rotatably connected to each other at their second end, causing the backrest to rotate towards the seat,

- a rotation of the supporting rod in a fixed position in which the connecting rod is abutting against a fixed stop with respect to the structure of the vehicle,

- then a movement of the seat towards a predetermined position by the transmission by the transmission link of the rotational movement of the backrest in a translation movement of the armchair.

Thus, the armchair according to the invention is placed back in a predetermined position when it is retracted and, this, thanks to a mechanism comprising two articulated connecting rods, the operation of which has no risk of jamming or blocking.

ES 2 306 972 T3

Advantageously, the seat comprises two parallel rails that can be embedded in the structure of the vehicle, in which the seat slides, one of the rails receiving a fitting that presents an articulation axis of the support rod and a stop against which the The support rod comes to rest when the backrest rotates.

In view of the reclining of the armchair, the seat comprises two base plates that slide on each of the rails and two seat arms joined to each of the plates by a front upright and two connecting rods.

To allow the backrest to tilt, it is made up of:

- two lower backrest plates attached to the two base plates and to the seat arms, and

- two upper backrest bales articulated on the two lower backrest plates.

For a better understanding, the invention is described with reference to the attached drawings which show as a non-limiting example an embodiment of the armchair according to the invention.

Figure 1 shows the structure of this chair in perspective, Figures 2 to 4 represent according to various successive positions an embodiment of a mechanism for positioning the chair in a predetermined location.

In the following description, the terms longitudinal, front, rear, upper and lower transverse refer to the reference of the vehicle.

In a classical way, the armchair that has the general reference 1, has a seat 2 on which a backrest 3 is articulated.

The seat 2 of the armchair comprises two base plates 4 and two seat arms 5, the connection between the base plates 4 and the seat arms 5 being made by an upright 6 in the shape of a scale and two connecting rods 7.

The assembly formed by the base plates 4, the upright 6, the seat arms 5 and the connecting rods 7 constitutes a deformable parallelogram since these elements are joined by joint axes that allow rotation.

It is also observed that a network of struts 8 ensures the cohesion of the seat in the transverse direction.

The lower part of each base plate 4 has a slide 9 which slides on a rail 10.

As regards the backrest 3, in the example of the armchair shown in figure 1, it is a backrest whose inclination can be adjusted. To this end, the backrest 3 is made up of two upper backrest plates 12 and two lower backrest plates 13; the union between the two upper backrest plates 12 and the two lower backrest plates 13 is made by a classic toothed sector mechanism that allows adjusting the inclination of the part of the backrest formed by the upper plates 12 with respect to the part formed by bottom plates 13.

Each of the lower backrest plates 13 is connected to the seat of the armchair 1 on the one hand by a rotation axis 14 at the level of the base plate 4 and by a rotation axis 15 at the rear end of the seat arm 5.

The back 3 also has a network of struts 8 that ensure the connection in the transverse direction between each of the upper and lower plates that constitute it.

The particularity of the armchair according to the invention is that it is provided with a mechanism comprising a connecting rod called the transmission link 16 joined by a rotation axis 20 at one of its ends to the lower back plate 13 and a second connecting rod called the transmission link. support 17 connected by an axis of rotation 21 to the rail 10 by means of a fitting 18 substantially in the shape of an inverted U. It is noted that the fitting 18 has a stop 19 whose function will appear later. The transmission rod 16 and the bearing rod 17 are connected to each other by a hinge pin 22.

The seat 1 thus defined constitutes an autonomous entity that can be placed on the floor of a vehicle that is being manufactured.

The rails 10 are fixed on the floor of this vehicle and functionally are an integral part of it. The seat can therefore slide longitudinally from front to back on its rails 10. A locking system that will not be described makes it possible to lock the seat in a position desired by its occupant with respect to the rails 10.

Thanks to their rotating joints 20, 21, 22, the transmission 16 and support 17 rods do not in any way hinder the movement of movement from front to back of the seat 1 with respect to the rails on which it can slide.

ES 2 306 972 T3

The retraction of the chair 1 will be explained in connection with Figures 2 to 4 which represent a chair on which the seat arms 5, the front upright 6 and the upper backrest plates 12 are not represented for clarity.

Figure 2 represents the armchair 1 in a non-retracted position, that is to say a position in which the backrest (of which only the lower part appears in this figure) is substantially in a position close to the vertical and can therefore accommodate a passenger. .

The longitudinal displacement of the seat 1 with respect to the rail results in a deformation of the mechanism formed by the support link 17 and the transmission link 16.

In a classical way, the chair has interlocking members with respect to the rails 10 that will not be described in more detail. These locking members make it possible to lock the chair in a desired longitudinal position.

When it is desired to retract the seat, an action is exerted on the backrest to fold it in the direction of the seat.

Although this has not been represented in Figures 2 to 4, it is then understood that the seat 2, which has a parallelogram structure, is deformed to become flat on the ground. This is a classic retractable armchair structure.

On the other hand, the particularity of the armchair, object of the invention, is that thanks to the mechanism constituted by the transmission rods 16 and the support rod 17, the seat 1 slides on the rails 10 to a predetermined location.

During the rotation of the backrest 3, beyond a certain angle, the locking members disengage from the rails 10. The chair is then free to move longitudinally with respect to the latter.

Indeed, due to the displacement of the lower plate 13 in the direction of the seat, the support rod 17, as can be seen in figure 3, comes to bear against the stop 19 present in the fitting 18.

It is recalled here that an important point of the armchair structure is that the fitting 18 is fixed with respect to the rail 10, that is to say, it is fixed with respect to the floor on which the armchair is mounted. Structurally, the hardware 18 resembles an element of the vehicle frame.

When the armchair is therefore in the configuration shown in Figure 3, the support rod 17 is in a fixed position with respect to the fitting 18.

Consequently, the rotation, which the lower backrest plate 13 continues to undergo to come into contact with the seat, is then translated into a rearward translation (in the embodiment represented in the figures).

In effect, the transmission connecting rod 16 is therefore fixed at its end connected to the supporting rod 17 and the rotational movement of the backrest is translated by a thrust exerted on the seat by this connecting rod in the longitudinal direction.

Figure 4 represents the chair when the backrest is fully folded down. The mechanism constituted by the transmission link 16 and the support link 17 thus makes it possible to put the chair back when it is in the retracted position, always in the same position whatever the starting position of the chair, that is, whatever the position may be. position of the seat with respect to rail 10. This position is determined, on the one hand, by the length of the transmission connecting rod and of the bearing rod and, on the other hand, by the longitudinal position of the axis of rotation 21 which joins the end of the bearing rod with respect to the fitting 18, that is to say with respect to the structure of the vehicle.

The invention thus described presents the numerous advantages indicated above since it allows a retractable seat to be put back in a predetermined position with respect to the floor of the vehicle in which it is mounted, while preserving the longitudinal mobility of this seat.

Of course, the invention is not limited to the embodiment described above by way of a non-limiting example, but rather comprises all variant embodiments. Thus, if in the example represented in the drawing, the predetermined position of the seat in its retracted position is located at the rear of the vehicle, it is of course possible to envisage that this predetermined position is located at the front of the vehicle and for this, it is sufficient to reverse the orientation angle of the supporting and transmission connecting rods with respect to each other.

On the other hand, it is possible to provide for fixing the support rod directly on the vehicle floor.