Car seat headrest

Abstract

The invention relates to a headrest (1) comprising a secondary body (4) mounted to slide longitudinally on a main body (3) by means of a locking device comprising a latch (5) mounted to slide vertically on said main body between a locked position and an unlocked position where it cooperates with and moves away from a rack (6) having a plurality of slots (22) having an inclined rear face (23) and a substantially vertical front face (24), said latch having a locking portion of a shape complementary to said slots, such that said latch placed in the locked position fits snugly into the slot (22) in which it is engaged, as well as another locking portion and an additional portion (25) arranged to fit into a slot at the rear end (30) of the rack (6) when said secondary body is disposed at the end of its forward travel.

Description

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

[0002] It is known, notably from document EP3802208, to produce a headrest for a motor vehicle seat, said headrest comprising: a mounting frame on a backrest of said seat, a main body mounted on said frame, a secondary body mounted to slide longitudinally on said main body so that said secondary body can adopt a plurality of longitudinal adjustment positions, said secondary body being provided with a wall for receiving the head of an occupant of said seat, a locking device for said secondary body in the chosen adjustment position, said device comprising a latch mounted to slide vertically on said main body between a locking position, where it cooperates with a locking rack extending longitudinally on said secondary body, and an unlocking position, where it moves away from said rack to release the sliding of said secondary body,said device further comprising a spring-loaded means for actuating said latch in the locking position and a means for actuating said latch in the unlocking position against said spring-loaded means, said rack having a plurality of similar grooves following one another longitudinally, said grooves having a rear face inclined relative to the vertical, so as to be concave, and a substantially vertical front face, so that the sliding of said secondary body forward is possible without having to unlock said device and that said sliding is blocked backward, said latch having a locking portion of a shape complementary to that of said grooves, so that said latch, when placed in the locked position, fits snugly into the groove in which it is engaged.

[0003] With such an arrangement, the seat occupant performs a simple pull of the secondary body forward to advance its adjustment position.

[0004] On the other hand, it is necessary to activate the locking device in unlocking mode in order to be able to push the secondary body back, the blocking of said body in rear sliding in the absence of voluntary unlocking being dictated by safety considerations, the headrest having to remain locked in its longitudinal adjustment position in the event of a head impact of the occupant on its receiving wall.

[0005] The fact that the latch has a locking part with a shape complementary to that of the grooves, so that said latch, when placed in the locked position, fits snugly into the groove in which it is engaged, allows the user operating the secondary body in pull to feel a sensation of precise positioning of said body in the chosen setting position, which gives a favorable qualitative impression.

[0006] However, the known design proves unsuitable for allowing perfect translation of the secondary body actuated by traction when the user performs this actuation asymmetrically with only one hand, as a rotation around a nearly vertical axis then begins; this results in a qualitatively unfavorable sensation. This situation arises from the fact that the locking mechanism is located in the middle portion of the latch viewed along a longitudinal direction.

[0007] It is also known to provide a rear end locking groove for the secondary body at the end of its forward stroke, said groove receiving the locking part of the latch, said groove having a substantially vertical front and rear face, said rear face blocking any forward movement of said secondary body at the end of its stroke.

[0008] However, with such an arrangement, the locking part of the latch and the end groove not having complementary shapes, it follows that said part does not fit into said groove in a tight manner.

[0009] Therefore, the user positioning the secondary body at the end of the stroke may experience a sensation of imprecise positioning of said body, which gives an unfavorable qualitative impression related to a lack of rigidity.

[0010] The invention aims to overcome these drawbacks.

[0011] To this end, the invention proposes a headrest for a motor vehicle seat, said headrest comprising: a mounting frame on a backrest of said seat, a main body mounted on said frame, a secondary body mounted to slide longitudinally on said main body so that said secondary body can adopt a plurality of longitudinal adjustment positions, said secondary body being provided with a wall for receiving the head of an occupant of said seat, a locking device for said secondary body in the chosen adjustment position, said device comprising a latch mounted to slide vertically on said main body between a locking position, where it cooperates with a locking rack extending longitudinally on said secondary body, and an unlocking position, where it moves away from said rack to release the sliding of said secondary body,said device further comprising a spring-loaded means for actuating said latch in locking and a means for actuating said latch in unlocking against said spring-loaded means, said rack having a plurality of similar grooves succeeding each other longitudinally, said grooves having a rear face inclined with respect to the vertical, so as to be concave, and a substantially vertical front face, so that the sliding of said secondary body forward is possible without having to unlock said device and that said sliding is blocked backward, said latch having a locking portion of a shape complementary to that of said grooves, so that said latch, when placed in the locked position, fits snugly into the groove in which it is engaged, , said headrest also having the following characteristics: said latch has another locking part, said locking parts being arranged laterally on either side in view along a longitudinal direction, said rack includes a rear end locking groove for said secondary body at the end of its forward travel, said groove being arranged in the middle part of said rack viewed in view along a longitudinal direction, said latch is provided with an additional locking part arranged between said locking parts so as to fit into said end groove when said secondary body is at the end of its forward travel, said end groove has a substantially vertical front face and rear face, said end groove having a shape complementary to that of said additional part so that said additional part fits snugly into said end groove,said rear face blocking any forward movement of said secondary body at the end of its stroke.

[0012] In this description, the terms of positioning in space (longitudinal, transverse, vertical, superior, inferior, front, rear, ...) are taken in reference to the headrest arranged in the vehicle in a situation of use, said vehicle extending longitudinally along its length (X axis), transversely along its width (Y axis) and vertically along its height (Z axis).

[0013] With the proposed arrangement, perfect translation of the secondary body actuated by pulling is ensured when the user performs this asymmetrical action with one hand, the aforementioned rotational initiation occurring minimally; this results in a qualitatively favorable sensation. This situation arises from the fact that the locking mechanism is engaged by the two lateral parts of the latch.

[0014] Furthermore, the additional locking part and the end groove having complementary shapes, it follows that said part fits into said groove in a tight manner, with the resulting qualitative advantage.

[0015] It should also be noted that the positioning of the end groove in the middle part allows for a clear separation of the intermediate and end-of-stroke locking functions.

[0016] Other features and advantages of the invention will become apparent in the following description, made with reference to the accompanying figures, in which: [ Fig.1 ] is a schematic semi-exploded partial perspective view of a headrest according to one embodiment, [ Fig.2A ] is a close-up schematic detail view of the figure 1 from another point of view, [ Fig.2B ] is another close-up schematic detail view of the figure 1 from another point of view, [ Fig.3A ] is a partial schematic view along a first vertical longitudinal section of the headrest of the preceding figures, the locking device being activated in lock in cooperation with two racks, [ Fig.3B ] is a partial schematic view according to a second vertical longitudinal section of the headrest of the previous figures, the locking device being activated in lock in cooperation with two locking notches of the secondary body at the end of forward travel.

[0017] With reference to the figures, a headrest 1 of a motor vehicle seat is described, said headrest comprising: a mounting frame 2 on a backrest of said seat, a main body 3 - in particular made of molded plastic material - mounted on said frame, a secondary body 4 - in particular made of molded plastic material - mounted to slide longitudinally on said main body, so that said secondary body can adopt a plurality of longitudinal adjustment positions, said secondary body being provided with a wall 21 for receiving the head of an occupant of said seat, a locking device for said secondary body in the chosen adjustment position, said device comprising a latch 5 mounted to slide vertically on said main body between a locking position, where it cooperates with a locking rack 6 extending longitudinally on said secondary body, and an unlocking position, where it moves away from said rack to release the sliding of said secondary body,said device further comprising a spring means 7 for actuating said latch in locking and a means for actuating said latch in unlocking - comprising for example a push button - against said spring means, said rack having a plurality of similar grooves 22 following one another longitudinally, said grooves having a rear face 23 inclined with respect to the vertical, so as to be concave, and a front face 24 substantially vertical, so that the sliding of said secondary body forward is possible without having to unlock said device and that said sliding is blocked backward, said latch having a locking portion 19a of a shape complementary to that of said grooves, so that said latch, when placed in the locked position, fits snugly into the groove 22 in which it is engaged, , said headrest also having the following characteristics: said latch has another locking part 19b, said locking parts being arranged laterally on either side in view along a longitudinal direction, said rack includes a rear end groove 30 for locking said secondary body at the end of its forward travel, said groove being arranged in the middle part of said rack viewed in view along a longitudinal direction, said latch is provided with an additional locking part 25 arranged between said locking parts 19a, 19b so as to fit into said end groove 30 when said secondary body is arranged at the end of its forward travel, said end groove 30 has a substantially vertical front face 26 and rear face 27,said end groove having a shape complementary to that of said additional part 25 such that said additional part fits snugly into said end groove, said rear face blocking any forward movement of said secondary body at the end of its stroke.

[0018] Specifically, the latch 5 having locking parts 19a, 19b of complementary shape to that of the grooves 22 means that a front face 31 of a locking part 19a, 19b makes a tight contact with the front face 24 of the groove 22 concerned and that a rear face 32 of said locking part makes a tight contact with the rear face 23 of said groove.

[0019] According to the embodiment shown, the frame 2 comprises two parallel metal rods 11.

[0020] According to the embodiment shown, the headrest 1 includes two latches 5 each cooperating with a respective rack 6, which strengthens the locking.

[0021] According to the embodiment shown, the latches 5 are generally in the form of plates sliding against each other in two opposite vertical directions.

[0022] According to the embodiment shown, a rack 6 is arranged on a guide member 17a, 17b sliding the secondary body 4 on the main body 3.

[0023] According to the embodiment shown, the guide member 17a, 17b is in the form of a tenon attached to the secondary body 4, said tenon sliding in a mortise 18a, 18b provided in the main body 3.

[0024] According to the embodiment shown, the headrest 1 comprises an upper tenon 17a and a lower tenon 17b each sliding in a respective upper mortise 18a and lower mortise 18b.

[0025] According to the representation shown: The latch 5 is provided with two rails 9 arranged laterally on either side, said rails extending longitudinally - and projecting vertically according to the embodiment shown - said rails cooperate by sliding with two reciprocal rails 10 - in the form of grooves according to the embodiment shown - provided on the secondary body 4, so as to lock said latch in rotation about a vertical axis when actuation in adjustment of said secondary body.

[0026] According to the embodiment shown, the latch 5 is provided with a notch 28 arranged in the median area of ​​said latch viewed in view along a longitudinal direction, said notch cooperating in sliding with a reciprocal rail 29 - projecting vertically according to the embodiment shown - provided on the secondary body 4, so as to lock said latch in rotation about a vertical axis when actuation in adjustment of said secondary body.

[0027] With such an arrangement, the additional part 25 extends on either side of the notch 28.

[0028] Such an arrangement, when applied in combination with the presence of side rails 9, provides reinforcement of the rotational locking of the latch 5.

[0029] Not shown, the main body 3 can be slidably mounted on the frame 2 so as to be able to adopt a plurality of vertical adjustment positions, said headrest including a locking device for said main body in the chosen adjustment position.

[0030] According to an embodiment not shown, the locking device for the main body 3 comprises: a plurality of locking notches arranged axially on at least one of the rods 11 (the term "axially" being considered in reference to the axis of extension of said rod) so as to define a notched rod, at least one locking projection mounted movable relative to said main body 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.

[0031] Not shown, the locking devices of the main body 3 and secondary body 4 can be actuated in unlocking by a common actuation means, said means comprising for example an actuation button - for example in the form of a push button - of a crossbar mounted on said main body in transverse sliding and cooperating with said devices.

Claims

1. Headrest (1) for a motor vehicle seat, said headrest comprising: • a frame (2) for mounting on a backrest of said seat, • a main body (3) mounted on said frame, • a secondary body (4) mounted so as to slide longitudinally on said main body, such that said secondary body can adopt a plurality of longitudinal adjustment positions, said secondary body being provided with a wall (21) for receiving the head of an occupant of said seat, • a device for locking said secondary body in the selected adjustment position, said device comprising a latch (5) mounted to slide vertically on said main body between a locking position, where it cooperates with a locking rack (6) extending longitudinally on said secondary body, and an unlocking position, where it moves away from said rack to release the sliding of said secondary body, said device further comprising spring means (7) for actuating said latch in the locking position and means for actuating said latch in the unlocking position against said spring means, said rack having a plurality of similar grooves (22) extending longitudinally, said grooves having a rear face (23) inclined relative to the vertical, so as to be undercut, and a substantially vertical front face (24), so that said secondary body can slide forwards without having to unlock said device and so that said sliding is blocked backwards, said latch having a locking part (19a) of a shape complementary to that of said grooves, so that said latch, when placed in the locking position, fits snugly into the groove (22) in which it is engaged, said headrest being characterised in that: • said latch has another locking part (19b), said locking parts being arranged laterally on either side in view in a longitudinal direction, • said rack comprises a rear end groove (30) for locking said secondary body at the forward end of its travel, said groove being disposed in the middle portion of said rack as viewed in a longitudinal direction, • said latch is provided with an additional locking part (25) disposed between said locking parts (19a, 19b) so as to insert into said end groove (30) when said secondary body is disposed at the forward end of its travel, • said end groove (30) has a substantially vertical front face (26) and rear face (27), said end groove having a shape complementary to that of said additional part (25) so that said additional part fits snugly into said end groove, said rear face blocking any forward movement of said secondary body at the end of its travel.

2. Headrest according to claim 1, characterised in that it comprises two latches (5), each cooperating with a respective rack (6).

3. Headrest according to any of the preceding claims, characterised in that a rack (6) is disposed on a member (17a, 17b) for guiding the sliding of the secondary body (4) on the main body (3).

4. Headrest according to the preceding claim, characterised in that the guiding member (17a, 17b) is in the form of a tenon connected with the secondary body (4), said tenon sliding in a mortise (18a, 18b) provided in the main body (3).

5. Headrest according to the previous claim, characterised in that it comprises an upper tenon (17a) and a lower tenon (17b), each sliding in a respective upper mortise (18a) and lower mortise (18b).

6. Headrest according to any of the preceding claims, characterised in that: • the latch (5) is provided with two rails (9) disposed laterally on either side, said rails extending longitudinally, • said rails cooperate in sliding with two respective reciprocal rails (10) provided on the secondary body (4), so as to lock said latch in rotation about a vertical axis when said secondary body is actuated for adjustment.

7. Headrest according to any of the preceding claims, characterised in that the latch (5) is provided with a notch (28) disposed in the middle area of said latch when viewed in a longitudinal direction, said notch cooperating in sliding manner with a reciprocal rail (29) provided on the secondary body (4), so as to lock said latch in rotation about a vertical axis when said secondary body is actuated for adjustment.

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