FR3005008A1 - VEHICLE SEAT COMPRISING AN ADJUSTABLE SEAT NOSE - Google Patents

Abstract

Seat for a motor vehicle comprising a seat (9), and a seat frame (3), an adjustable seat nose (7), the seat nose comprising a pivoting support (1) pivotally mounted relative to the seat frame, a sliding carriage (2) slidably mounted relative to the pivoting support (1), a control rod (4) connected at a first end to the sliding carriage by a first mechanical connection (L1), and articulated with respect to the armature, an actuating member (5), connected to the control rod (4) by a second mechanical link (L2), in which the actuating member makes it possible to move simultaneously, thanks to the control rod , both the pivotally pivoting support and the sliding slide carriage.

Description

The present invention relates to vehicle seats having an adjustable seat nose.

It relates more particularly to a seat for a motor vehicle comprising: - a seat, allowing a user to sit on said seat, and having a seat frame, - a seat nose adjustable in height and in length relative to to the seat frame. Such seats equipped with adjustable seat nose in position in two directions are already known, as for example in document FR2776579, which has a complex and relatively heavy and expensive seat nose configuration. The present invention is intended in particular to simplify and optimize the seats equipped with such seat nose adjustable in position. For this purpose, according to the invention, there is provided a seat for a motor vehicle comprising: - a seat, allowing a user to sit on said seat, and having a seat frame, - a seat nose adjustable in position relative to the seat, the seat nose comprising: - a pivoting support pivotally mounted relative to the seat frame about a transverse axis, - a sliding carriage slidably mounted relative to the support pivoting along a sliding axis, a control rod connected, at a first end zone, to the slide carriage by a first mechanical connection, and articulated with respect to the armature, an actuating member connected to the control rod by a second mechanical connection, characterized in that the actuating member makes it possible to move, thanks to the control rod, simultaneously, both the pivotally pivoting support and the sliding carriage in sliding. Thanks to these arrangements, it is proposed the two adjustment directions (length and height) for the seat nose, obtained with a single actuator which contributes to lighten and simplify the seat structure. This also allows to have a single user command, very simple to use. In various embodiments of the invention, one or more of the following provisions may also be used: the actuating member may be a geared motor connected to a second zone; end of the control rod; which provides good ease of use and which improves comfort and safety; - The actuating member may be a manually operated knob connected by at least one gear to the control rod; whereby we have a simple, reliable and inexpensive solution; - The control rod can be articulated on a fixed bearing relative to the frame; which is a particularly simple solution; the first mechanical link may be a pivot link; which is a reliable and robust solution; the first mechanical connection can be a sliding support, the mechanical connection further comprising a return spring to a retracted position of the sliding carriage and an auxiliary sliding support between the first end zone and a lower bearing surface of the pivoting support; which represents a particularly simple alternative arrangement; the second mechanical connection may comprise a nut-bushing receiving a helical screw driven by the actuating member, the nut-bushing being pivotally mounted on the second end zone of the connecting rod; which represents a simple solution for transforming a rotary motion into a substantially linear movement with a good reduction ratio; - The actuating member and the fixed bearing may is mounted on a plate which extends between left and right flanges of the seat frame, the plate comprising the fixed bearing; this gives good modularity and ease of installation; - The actuating member and the control rod can be disposed substantially midway between the left and right flanges of the seat frame; so that a good symmetry and a satisfactory center of effort are obtained; the angular travel of the pivoting support is at least 6 degrees, preferably up to 8 degrees, and the translation travel of the sliding carriage is at least 40 mm, preferably up to 60 mm; whereby a possible adjustment for all the usual morphologies of the occupants. - The pivoting support, the sliding carriage and the control rod are made of plastic; which is favorable for the lightening, the obtaining of complex forms, the integration of the fixings and the reduction of the number of pieces.

Other aspects, objects and advantages of the invention will appear on reading the following description of two of its embodiments, given by way of non-limiting examples. The invention will also be better understood with reference to the accompanying drawings, in which: FIG. 1 is a side view of a motor vehicle seat according to a first embodiment of the invention, FIG. 2 is an exploded view. in perspective of the seating structure of the seat of Figure 1, - Figure 3 is a schematic side view, the seat nose being in the retracted position, - Figure 4 is a schematic side view, the nose of the seat. 5 is similar to Figure 3 for a second embodiment, - Figure 6 is similar to Figure 4 for the second embodiment of Figure 5. In the various figures, the same references designate identical or similar elements. FIG. 1 represents a schematic side view of a motor vehicle seat 10 according to the invention, this seat comprising a backrest 20 and a seat 9 on which a user of the seat can sit. The longitudinal direction noted X extends back and forth relative to the seat.

It is usual to mount such a seat 10 on longitudinal rails comprising on the one hand a fixed section 94 connected to the structure 95 of the vehicle, and on the other hand a movable section 93 whose longitudinal position can be adjusted relative to the profile fixed 94. In addition, it can be provided a height adjustment of the seat by pivoting two connecting rods 91,92 raisers according to a mechanism known per se. Said seat 9 extends in said longitudinal direction X between a front portion 9a and a rear portion 9p. Referring further to Figure 2, said seat 9 comprises a seat frame 3 made in the example shown as a metal welded structure. The frame can also be made of magnesium, plastic, or any other solid and lightweight material. The frame is covered with a flexible padding and an outer covering 19 (not shown in Figures 2 to 6). In addition, said seat 9 comprises a seat nose 7 35 arranged on the front portion 3a of the seat frame. As is known, the seat nose 7 can be adjustable in position relative to the seat, in length that is to say substantially along the longitudinal direction X, and in height. The adjustment (or 'adjustment') is provided so that the seat nose 7 can adapt to all the morphologies of the possible occupants of the vehicle: in particular the extreme positions shown in phantom and continuous in Figure 1. Referring in Figure 2, the seat frame 3 comprises a left flange 3g and right flask 3d which are connected together by transverse parts (not shown in full) to form together a welded frame lightweight and very good strength. More specifically, the seat nose 7 comprises a pivoting support 1 hinged about a pivot axis Y1 transverse. Said pivoting support 1 comprises two pivot bearings 14 adapted to pivot respectively on the left and right flanges 3g of the armature 3, and lateral support portions 17 interconnected by a central transverse portion 15. On the front end of the pivoting support 1 may be formed laterally bulges upwardly 11,12 for the lateral support of the thighs of the user and two vertical fall 13 to define the front portion of the seat on its sides. Furthermore, in the central median zone, there is provided a recess 16 whose function and utility will be seen further. Said pivoting support 1 is preferably made of plastic and comprises, in a manner known per se, guide rails 18 for guiding a sliding carriage 2 in translation. Said sliding carriage 2 forms the upper front part of said seat nose and moves in translation in a direction of sliding W which has an angular deviation with the longitudinal direction X relatively moderate; in this way the movement of the sliding carriage 2 from front to back provides adjustment of the length of the nose. The sliding carriage comprises a plate 20, two lower rails 28 corresponding in shape with the guide rails 18 already mentioned, a front drop 24 which delimits frontally the nose to the front, and various equipment or forms of attachment 27 adapted to receive the specific padding of the sliding carriage.

The angular travel of the pivoting support is at least 6 degrees, preferably up to 8 degrees; the translational travel of the sliding carriage is at least 40 mm, preferably up to 60 mm. This makes it possible to adapt the seat nose 7 to all the morphologies of the individuals likely to take place on the seat (children not included). The pivoting support and the sliding carriage are displaced by means of a control rod 4 which comprises a first end zone 41 in mechanical interface with the sliding carriage as will be detailed hereinafter and a second zone d end 42 connected to an actuator 5 which will be seen in detail later. The control rod 4 is articulated in its middle portion relative to the seat frame 3; more precisely in the illustrated example, it is pivotally mounted about a fixed axis Y2 relative to the armature. A central plate 6 firstly comprises a transverse tube 60 which extends from the left armature plate 3g to the right armature flange 3d. The central plate 6 further comprises two support arms 62 each equipped with a bearing 61 centered on the axis Y2, said bearings being intended to pivotally receive journals 44 arranged in the middle portion of the control rod. Furthermore, the central plate comprises a support 64 with bearings to serve as anchoring point of the attachment of the actuating member 5. In the example illustrated, the actuating member 5 is in the form of a geared motor assembly comprising a base 52 connected to the support 64 bearing, an electric motor 51, connected by a gear to a worm 53 X2 axis, and a nut bush 54 equipped with pins 55 and rotatably mounted relative to the second zone end 42 the control rod with said trunnions.

Advantageously, as illustrated in the figures, the actuating member and the control rod are disposed substantially mid-way between the left and right flanges of the seat frame, which makes it possible to have a good centering of the forces and which avoids any unwanted jamming of the sliding carriage. Instead of the geared motor, the actuating member could just as easily be a manually controlled wheel system (configuration not shown); in this case the lower part of the control rod 4 could be quite different. The kinematics proposed with reference to FIGS. 3 to 6 is now more specifically studied. In FIG. 3, the pivoting support 1 is in the low position and the sliding carriage 2 is in the maximum rear position, the control rod 4 being almost in a position. horizontal position. In this embodiment, the rear central portion of the sliding carriage comprises at least one bearing 23 of axis Y5 in which is received a crank pin 46 disposed at the first end zone 41 of the control rod, which forms a pivot connection between the connecting rod and the sliding carriage. When the user wants to increase the grip and the influence of the seat nose, then he can control by means of a button the rotation of the motor 51 to turn the worm 53 is thus bring the nut sleeve 54 closer to the engine; this results in a rotation of the rod in the trigonometric direction which moves the hinge Y5 upwards and simultaneously forward. As a result, the pivot support 1 rotates relative to its hinge axis Y1 (clockwise) and simultaneously the slide carriage 2 moves away from its retracted position towards a position exit. An infinite number of intermediate positions is possible up to the maximum output position shown in FIG. 4, in which the control rod 4 has an almost vertical position. In the illustrated example, during the extension movement mentioned above, the geared motor assembly 5 rotates slightly with respect to its fixing hinge Y4. The pitch of the screw-nut connection between the screw 53 and the nut-bushing 54 is such that a force exerted on the seat nose does not make it possible to turn the screw and / or the motor. Therefore, the position of the seat nose 7 remains constant when the engine does not rotate, including when the seat is subjected to vibration stresses or efforts exerted by the user. When the user wants to tilt and / or lower the seat nose, he can actuate the motor in the opposite direction to that previously described, which proves a distance from the second end zone 42 of the control rod. to the motor and therefore the rotation of the control rod 4 in the direction of the clockwise. It follows a lowering of the pivoting support 1 and a retraction of the sliding carriage 2 to the rear. Figs. 5 and 6 show a second embodiment in which only the points discussed below differ, all that is not described being assumed to be similar or identical to that described for the first embodiment. The first mechanical connection, generically called in this document by the reference Li, connecting the first end zone 41 of the control rod 4 to the sliding carriage 2 is different; indeed, it is a sliding support in which the crankpin 46 is supported on a substantially vertical support plane 25 arranged at the rear end of the sliding carriage (replacing the bearing 23 previously described).

Furthermore, an elastic return means 8, in this case a spring, which in the illustrated example works in compression, pushes the sliding carriage back and forth relative to a reference support 29 disposed under the pivoting support. The return force of the spring makes it possible to maintain permanent contact between the support plane 25 and the crank pin 46 of the control rod. In Figure 5, the spring is extended and not compressed although still slightly in compression; in Figure 6, the spring 8 is compressed to the maximum position which corresponds to the maximum extension of the carriage sliding outwards. Moreover, the zone of the first end zone 41 of the control rod and resting on a lower bearing surface 71 of the pivoting support; this support is slippery, the support zone moving with the translational movement of the sliding carriage. It should be noted that the device may contain two springs arranged on either side of a median plane to ensure a good balance of the return force and avoid any potential jamming. In this second embodiment, the geared motor unit 5 is attached to a Y4 axis support bearing positioned in front of the Y2 axis, which represents an alternative that can also be used with the first embodiment. In the extension direction, the control rod 4, controlled by the geared motor 5, rotates in the counterclockwise direction and consequently pushes the carriage outwards against the action of the spring 8 and simultaneously pushes the support pivoting upwards against gravity. In the opposite direction (retraction), the control rod 4 is erased by turning in a clockwise direction, the pivoting support is lowered by the effect of gravity, and the sliding carriage makes a retractable movement. under the effect of spring action 8.

Advantageously, for the first and second embodiments presented above, the main plastic parts are produced, in particular the pivoting support 1, the sliding carriage 2, the control rod 4 and, if appropriate, other parts such as the support plate 6. It should be noted that for the first and second embodiments presented above, the second mechanical connection L2 which corresponds to the interface between the sleeve-nut and the second end zone of the control rod could be of another nature, for example using an auxiliary connecting rod, which one could have the engine in a fixed position relative to the frame. It should also be noted that in the case of manual wheel control, the control rod can be driven in any known manner from a rotary shaft, for example via a toothed sector connection.

Claims (11)

REVENDICATIONS1. Seat for a motor vehicle comprising: a seat (9), allowing a user to sit on said seat, and having a seat frame (3), a seat nose (7) adjustable in position relative to the seat, the seat nose comprising: - a pivoting support (1) pivotally mounted relative to the seat frame about a transverse axis (Y1), a sliding carriage (2) slidably mounted relative to at the pivoting support (1) along a sliding axis (W), a control rod (4) connected to a first end zone (41) to the sliding carriage by a first mechanical connection (L1) and articulated with respect to the seat frame, - an actuating member (5), connected to the control rod (4) by a second mechanical connection (L2), characterized in that the seat member actuation makes it possible to simultaneously move, thanks to the control rod, both the pivotally pivoting support and the sliding slide carriage . 25 2. Seat according to claim 1, wherein the actuating member (5) is a geared motor connected to a second end zone (42) of the control rod (4). The seat according to claim 1, wherein the actuating member is a manually operated knob connected by at least one gear to the control rod (4). 4. Seat according to one of claims 1 to 3, wherein the control rod (4) is articulated on a fixed bearing (61) relative to the seat frame (3). 5. Seat according to one of claims 1 to 4, wherein the first mechanical connection (L1) is a pivot link (Y5). 6. Seat according to one of claims 1 to 4, wherein the first mechanical connection (L1) is a sliding support, and the mechanical connection further comprises a return spring (8) to a retracted position of the sliding carriage and a auxiliary sliding support between the first end zone (41) and a lower bearing surface (71) of the pivoting support. 7. Seat according to one of claims 1 to 6, wherein the second mechanical connection (L2) comprises a nut-bushing (54) receiving a helical screw (53) driven by the actuating member, the nut-bushing being pivotally mounted (Y3) on the second end zone (42) of the connecting rod. 8. Seat according to claim 2 and claim 4, wherein the actuating member (5) is mounted on a plate (6) which extends between left and right flanges (3g, 3d) of the armature seat, the plate comprising the fixed bearing (61). 9. Seat according to claim 8, wherein the actuating member and the control rod are disposed substantially midway between the left and right flanges (3g, 3d) of the seat frame. 10. Seat according to one of the preceding claims, wherein the angular travel of the pivoting support is at least 6 degrees and the translational travel of the sliding carriage is at least 40 mm. 11. Seat according to one of the preceding claims, wherein the pivoting support, the sliding carriage and the control rod are made of plastic.