Headrest for motor vehicle

Description

[0001] The invention relates to a headrest for a motor vehicle seat.

[0002] It is known to produce a headrest for a motor vehicle seat, said headrest comprising: a mounting frame on a back of said seat, a main body mounted in the upper part of said frame, a secondary body mounted in longitudinal sliding on said main body, so that said secondary body can adopt a plurality of positions, said secondary body being integral with a wall supporting the head of a passenger.

[0003] However, arrangements known as that of DE 102018 221626 B3: do not allow for optimal control of the correct sliding of the secondary body in relation to the main body, due to arching phenomena and / or dimensional dispersions which are detrimental to said sliding and the rigidity of the assembly, generally require a significant number of means of compensating for play.

[0004] The invention aims to overcome these drawbacks.

[0005] To this end, the invention proposes a headrest for a motor vehicle seat, said headrest comprising: a mounting frame on a back of said seat, a main body mounted in the upper part of said frame, a secondary body mounted in longitudinal sliding on said main body, so that said secondary body can adopt a plurality of positions, said secondary body being integral with a wall supporting the head of a passenger, said secondary body being mounted on said main body by at least one tenon arranged on the periphery of one of said bodies, said tenon having in longitudinal view a shape fitting into a trapezoid having a large base facing inwards and a small base facing outwards, said tenon sliding in a mortise of complementary shape, opening outwards through said small base, provided in the other of said bodies, so as to form a “dovetail” type fixing.

[0006] In this description, the terms of positioning in space (top, bottom, upper, lower, longitudinal, transverse, lateral, front, rear, vertical, etc.) are taken in reference to the headrest arranged in the vehicle in use.

[0007] With the proposed arrangement, guidance is provided by means arranged in the peripheral zone of the headrest, which allows: to better control the correct sliding of the secondary body in relation to the main body, with elimination of the phenomena of arching and / or impact of dimensional dispersions harming said sliding and the rigidity of the assembly, to reduce the number of means of taking up play, as will be seen later.

[0008] Other features and advantages of the invention will appear in the following description, given with reference to the attached figures, in which: [ Fig.1 ] is a partial schematic perspective view of a headrest according to one embodiment, [ Fig.2 ] is analogous to the figure 1 in exploded view, [ Fig.3 ] is a schematic view along a longitudinal direction of the main body of the illustrated embodiment, [ Fig.4 ] is a schematic view along a longitudinal direction of the secondary body of the illustrated embodiment, [ Fig.5 ] is a schematic view along a longitudinal direction of the secondary body mounted on the main body, [ Fig.6 ] is analogous to the figure 1 , the headrest being further provided with two shells.

[0009] With reference to the figures, a headrest 1 for a motor vehicle seat is described, said headrest comprising: a frame 14 for mounting on a back of said seat, a main body 3 - in particular made of molded plastic material - mounted in the upper part of said frame, a secondary body 4 - in particular made of molded plastic material - mounted in longitudinal sliding on said main body, so that said secondary body can adopt a plurality of positions, said secondary body being integral with a support wall 5 for the head of a passenger, said wall being in particular covered with a cushion not shown, said secondary body being mounted on said main body by at least one tenon 6 arranged on the periphery of one of said bodies - here said secondary body -, said tenon having in longitudinal view a shape falling within a trapezoid having a large base facing inwards and a small base facing outwards, said tenon sliding in a mortise 8 of complementary shape, opening outwards through said small base, provided in the other of said bodies, so as to form a “dovetail” type fixing.

[0010] According to the embodiment shown, the frame 14 comprises two substantially vertical parallel metal tubular branches 2.

[0011] According to the embodiment shown, the branches 2 of the frame are separated from each other.

[0012] According to a variant not shown, the branches 2 are connected to each other by a spacer extending between their upper ends, the frame being produced in particular by folding a metal tube into an inverted U, the branches of the U corresponding to the branches 2 of said frame and its intermediate part forming said spacer.

[0013] According to the embodiment shown, the headrest 1 comprises two tenons 6 facing each other along two opposite edges - here the upper and lower edges - of the body 4 on which they are arranged, in this case the secondary body 4 according to the embodiment shown.

[0014] According to the embodiment shown, the facing tenons 6 are positioned in the middle of the edges concerned, this in order to ensure optimal sliding of the secondary body 4, including when it is actuated by its lateral part.

[0015] A lateral face of a mortise 8 and / or a tenon 6 is provided with an elastically retractable tab 9, so as to ensure tight contact with the corresponding tenon 6 and / or mortise 8. According to the embodiment shown, the lateral face of the mortise 8 is provided with a tab 9 ensuring tight contact with the corresponding tenon 6.

[0016] With such an arrangement, the clearances between a tenon 6 and the corresponding mortise 8 are taken up in two directions, namely the vertical and transverse directions.

[0017] According to the embodiment shown, the tab 9 is molded from the body 3 concerned - here the main body 3 -, said tab being secured to said body by one of its ends 10, said tab being stressed by a metal spring 7 to ensure the tightening contact.

[0018] According to the embodiment shown, the clamping contact is ensured by two tabs 9 arranged respectively at the top and bottom of the body 3 concerned - in this case the main body 3 according to the embodiment shown -, said tabs being moreover laterally opposite, which makes it possible to ensure both vertical and transverse centering while minimizing the number of said tabs.

[0019] With such an arrangement, only two means of taking up play are used, formed by the two legs 9 associated with the springs 7.

[0020] In a manner not shown, the headrest 1 may further comprise a device for locking the secondary body 4 in a plurality of positions, so that the support wall 5 may have a plurality of adjustment positions.

[0021] According to an embodiment not shown, the locking device of the secondary body 4 may comprise: a rack originating from said secondary body, said rack extending longitudinally, a latch mounted to move relative to the main body 3 between a locking position, where it is inserted into a notch of said rack, and an unlocking position, where it is withdrawn from said notch in order to release the sliding of said secondary body.

[0022] In a manner not shown, the main body 3 can be slidably mounted on the frame 14, and in particular on the branches 2, the headrest 1 comprising a device for locking the height of said body, so as to allow it to be locked in an adjustment position.

[0023] According to one embodiment, the height locking device may comprise: at least one notched branch 2 provided with axially staggered adjustment notches, that is to say along the extension axis of said branch, at least one locking projection mounted to move relative to the main body 3 between a locking position, where said projection is inserted into one of said notches, and an unlocking position, where said projection is withdrawn from said notch in order to release the sliding of said body.

[0024] According to various embodiments, the secondary body 4 can be molded in one piece with the support wall 5 or constitute a separate part which is mounted on said wall.

[0025] According to the embodiment shown, the secondary body 4 is integral with two front hulls 11 and rear 12 associated with each other - here by means of screws 13 - to form a housing housing said body, the wall of said front shell forming the support wall 5.

[0026] According to the embodiment shown, the secondary body 4 is separate from the shells 11,12, said body being made integral with said shells by their assembly between them.

[0027] With such an embodiment, it is possible to produce the secondary body 4 from a plastic material that is not very susceptible to deformation in the event of heat (for example polyamide or acrylonitrile butadiene styrene), which makes it possible to optimize the guidance of said body at all operating temperatures of the vehicle, the shells 11, 12 being able to be produced from a plastic material (for example high-density polyethylene) that is less resistant to temperature fluctuations, and in particular less expensive.

[0028] According to an embodiment not shown, the secondary body 4 is molded in one piece with one of the shells 11, 12.

[0029] In this case, it is appropriate to produce the shell 11, 12 in a single piece with the secondary body 4 based on a plastic material that is not very susceptible to deformation in the event of heat (for example polyamide or acrylonitrile butadiene styrene) if it is desired to optimize the guidance of said body at all vehicle operating temperatures.

[0030] Of course, you can use a lower quality plastic material (for example, high-density polyethylene), but then you have less efficient guidance.

Claims

1. Headrest (1) for a motor vehicle seat, said headrest comprising: - a frame (14) for mounting on a backrest of said seat, - a main body (3) mounted on an upper part of said frame, - a secondary body (4) longitudinally slidably mounted on said main body, so that said secondary body can adopt a plurality of positions, said secondary body being connected with a support wall (5) of a passenger's head, said headrest being characterized in that said secondary body is mounted on said main body by at least one tenon (6) disposed at a periphery of one of said bodies, said tenon having, in longitudinal view, a shape inscribed in a trapezoid having a large inwardly-facing base and a small outwardly-facing base, said tenon sliding in a mortise (8) of complementary shape, opening out outwardly through said small base, provided in the other of said bodies, so as to form a dovetail-type fastening.

2. Headrest according to claim 1, characterized in that it comprises two tenons (6) facing each other along two opposite edges of the body (4) on which they are arranged.

3. A headrest according to one of claims 1 or 2, characterized in that one side face of a mortise (8) and / or tenon (6) is provided with an elastically retractable tab (9), so as to ensure clamping contact with the corresponding tenon (6) and / or mortise (8).

4. Headrest according to claim 3, characterized in that the tab (9) is molded from the concerned body (3), said tab being connected with said body by one of its ends (10), said tab being stressed by a metal spring (7) to ensure the clamping contact.

5. Headrest according to one of claims 3 or 4 when dependent on claim 2, characterized in that the clamping contact is ensured by two tabs (9) arranged respectively at the top and bottom of the concerned body (3), said tabs also being laterally opposed.

6. Headrest according to any of the preceding claims, characterized in that it further comprises a device for locking the secondary body (4) in a plurality of positions, so that the support wall (5) can have a plurality of adjustment positions.

7. Headrest according to any one of the preceding claims, characterized in that the secondary body (4) is connected with two front (11) and rear (12) shells associated with each other to form a housing accommodating said body, the wall of said front shell forming the support wall (5).

8. Headrest according to claim 7, characterized in that the secondary body (4) is distinct from the shells (11, 12), said body being made connected with said shells by their assembly together.

9. Headrest according to claim 7, characterized in that the secondary body (4) is molded in one piece with one of the shells (11, 12).