FR3063045A1 - HEADREST FOR THE SEAT OF A MOTOR VEHICLE - Google Patents

Abstract

The invention a headrest (1) comprising an armature (2), a base (3), a movable part (4) and a locking device of said part in the selected adjustment position, said device comprising a gear wheel (6) and means for locking the rotation of said wheel, said locking means comprising at least a first (8) and a second (9) latch each having a locking end (11), said first latch being provided with an actuating member (12) for actuating it to an unlocking position, said first latch having a bearing face (13a) on a sliding face (14a) provided on said second latch, said faces being resting against each other by a spring means (22) so that actuation of one of said latches in one direction effects actuation of the other of said catches in the same direction, said spring means being furthermore arranged to actuate said latches to their locking position.

Description

063 045

51396 ® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY

COURBEVOIE © Publication number:

(to be used only for reproduction orders)

©) National registration number © Int Cl ⁸ : B 60 N2 / 806 (2017.01)

PATENT INVENTION APPLICATION

A1

©) Date of filing: 22.02.17. (© Applicant (s): CERA TSC Société par actions simpli- (© Priority: trusted - FR. @ Inventor (s): SOY ALBERT. ©) Date of public availability of the request: 24.08.18 Bulletin 18/34. ©) List of documents cited in the report preliminary research: Refer to end of present booklet (© References to other national documents ©) Holder (s): CERA TSC Société par actions simpli- related: trusted. ©) Extension request (s): (© Agent (s): STRATO-IP Limited liability company.

MOTOR VEHICLE SEAT SUPPORT.

FR 3,063,045 - A1

The invention a headrest (1) comprising a frame (2), a base (3), a movable part (4) and a device for locking said part in the chosen adjustment position, said device comprising a toothed wheel (6) and means for locking the rotation of said wheel, said locking means comprising at least a first (8) and a second (9) latches each having a locking end (11), said first latch being provided with an actuating member (12) enabling it to be actuated towards an unlocking position, said first latch having a bearing face (13a) on a sliding face (14a) provided on said second latch, said faces being placed resting against each other by a spring means (22) so that actuation of one of said latches in one direction actuates the other of said latches in the same direction, said spring means being further arranged to actuate said latches towards their locked position.

The invention relates to a headrest for a motor vehicle seat.

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 base fixed in the upper part of said frame, • a part movable relative to said base so as to be able to be positioned by the occupant of said seat according to a plurality of adjustment positions, said part being provided with a cushion receiving face, • a device for locking said part in the chosen adjustment position, said device comprising a toothed wheel rotatably mounted along a main axis, said wheel being connected to said part so that a movement of said part from one adjustment position to another causes a corresponding rotation of said wheel, said device further comprising means for locking the rotation of said wheel in at least one direction.

Known locking means is in the form of a latch mounted to rotate about a secondary axis parallel to said main axis, said latch has a locking end arranged to be able to be introduced between the teeth of said wheel and to block it in rotation, in order to put said latch in the locked position.

With such an arrangement, there is the risk of having insufficient locking of the mobile part in its adjustment position in the event of a violent impact of the head of a passenger on the headrest, which is dangerous.

The object of the invention is to overcome this drawback.

To this end, the invention provides a headrest for a motor vehicle seat, said headrest comprising:

• a mounting frame on a back of said seat, • a base fixed in the upper part of said frame, • a part movable relative to said base so as to be able to be positioned by the occupant of said seat according to a plurality of adjustment positions, said part being provided with a cushion receiving face, • a device for locking said part in the chosen adjustment position, said device comprising a toothed wheel rotatably mounted along a main axis, said wheel being connected to said part so that a displacement of said part from one adjustment position to another causes a corresponding rotation of said wheel, said device further comprising means for locking the rotation of said wheel in at least one direction, said headrest also having the following characteristics:

• said locking means comprises at least first and second latches mounted to rotate along secondary axes parallel to said main axis, said latches each having a locking end arranged to be able to be introduced between teeth of said wheel and block it in rotation , in order to put said latches in the locking position, • said first latch is provided with an actuating member enabling it to be actuated in rotation towards an unlocking position in which its locking end moves away from said wheel, • said first latch has a bearing face on a sliding face provided on said second latch, said faces being pressed against one another by a spring means, said faces being shaped so that an actuation of one of said latches in rotation in one direction actuates in rotation the other of said latches in the same direction, in order to ensure a coordinated placing of said latches in the locked or unlocked position, said spring means being further arranged so as to actuate said latches towards their locked position.

In this description, the terms of positioning in space (upper, longitudinal, lateral, front, rear, vertical, transverse, etc.) are taken with reference to the headrest mounted in the vehicle in configuration of use .

With the proposed arrangement, the movable part is locked in the chosen position by a plurality of latches, which makes it possible to ensure reinforced locking.

In addition, putting the latches in the unlocking position is done by actuating a single actuating member, which has optimized ergonomics.

Other features and advantages of the invention will appear in the following description, made with reference to the attached figures, in which:

• Figure 1 is a partial schematic view in longitudinal vertical section of a headrest according to one embodiment, • Figures 2a and 2b are schematic partial perspective views of the headrest of Figure 1 with a means of locking according to a first embodiment, in exploded view (Figure 2a) and not exploded (Figure 2b), said means being activated, • Figures 3a and 3b are front views corresponding to Figure 2b, the locking means being activated (Figure 3a) and deactivated (Figure 3b), • Figure 4 is a schematic partial perspective view of the headrest of Figure 1 with a locking means according to a second embodiment, said means being activated.

With reference to the figures, a headrest 1 of a motor vehicle seat is described, said headrest comprising:

• a frame 2 for mounting on a back of said seat, • a base 3 fixed at the top of said frame, • a part 4 movable relative to said base so as to be able to be positioned by the occupant of said seat in a plurality of positions adjustment, said part being provided with a face 5 for receiving a cushion, • a device for locking said part in the chosen adjustment position, said device comprising a toothed wheel 6 rotatably mounted along a main axis 7, said wheel being connected to said part so that a displacement of said part from one adjustment position to another causes a corresponding rotation of said wheel, said device further comprising means for locking the rotation of said wheel in at least one direction, said headrest further having the following characteristics:

Said locking means comprises at least a first 8 and a second 9 latches mounted to rotate along secondary axes 10 parallel to said main axis, said latches each having a locking end 11 arranged to be able to be introduced between teeth of said wheel and block it in rotation, in order to put said latches in the locking position, • said first latch is provided with an actuating member 12 - here in radial projection - enabling it to be actuated in rotation towards an unlocking position in which its locking end 11 departs from said wheel, • said first latch has a bearing face 13a on a sliding face 14a provided on said second latch, said faces being brought into abutment against one another by means spring 22, not visible in the figures, said faces being shaped so that actuation of one of said latches in rotation in a direction r alise an actuation in rotation of the other of said latches in the same direction, in order to ensure a coordinated placing of said latches in the locking or unlocking position, said spring means being further arranged so as to actuate said latches towards their position locking.

According to a first embodiment of the locking means, shown in Figures 2 and 3, the headrest further comprises a third latch 15 succeeding the second latch 9, said second latch comprising a bearing face 13b on a face of sliding 14b provided on said third latch, in order to ensure a coordinated setting of all the latches 8, 9, 15 in the locked or unlocked position.

According to a second embodiment of the locking means, shown in FIG. 4, the headrest comprises at least four - here five - latches 8, 9, 15, 16, 17 similar distributed around the toothed wheel 6 according to a rotational symmetry, each of said latches comprising a bearing face 13a, 13b on a sliding face 14a, 14b provided on one of said latches succeeding it, in order to ensure a coordinated placing of all said latches in the locked or unlocked position .

According to the embodiments shown, the teeth of the toothed wheel 6 have a geometry arranged so that the locking means in the locking configuration blocks the rotation of said wheel in the direction corresponding to a retraction of the movable part 4 and does not block said rotation in the direction corresponding to an advance of said movable part.

With such an arrangement, it is not useful to deactivate the locking means in order to carry out an adjustment towards the front, the movable part 4 however remaining firmly held in its adjustment position in the event of impact from the head of a passenger on

According to the first embodiment, the spring means 22 is in the form of a metal wire shaped so as to have two branches respectively bearing on two successive latches 9,15 so as to put them in the locked position.

According to one embodiment, represented in FIG. 1:

• the mobile part 4 is mounted in longitudinal sliding relative to the base 3, so that it can be positioned in a plurality of adjustment positions by application of a longitudinal force applied manually by a user to said mobile part, • said headrest comprises at least one endless screw 18 extending along the main axis 7, said screw being rotatably mounted on said movable part, said screw being received in a threaded orifice 19 made in said base, said screw having at at least one thread inclined relative to said axis so as to allow said movable part to slide by application of said longitudinal force, • the toothed wheel 6 is integral with one of the ends of said screw so as to rotate with said screw around said axis .

In particular, a screw 18 has at least three threads distributed around the main axis 7 according to a rotational symmetry.

In particular, the mobile part 4 is in the form of a housing comprising a front wall 20, located in front of the base 3, and a rear wall 21, located behind said base, a screw 18 being mounted for rotation around a shaft connecting said front and rear walls.

According to one embodiment, a screw 18 has an overall diameter between 30 and 50 mm.

According to one embodiment, a screw 18 has, with reference to a thread, a pitch of between 90 and 100 mm.

In an embodiment not shown, the mobile homeland 4 is mounted in rotation along a transverse axis, so as to be adjustable in inclination.

In this case, the toothed wheel 6 is mounted integral with the movable part 4 so as to be in rotation around the above-defined transverse axis which coincides with the main axis 7.

Claims (5)

1. Headrest (1) of a motor vehicle seat, said headrest comprising • a frame (2) for mounting on a back of said seat, • a base (3) fixed in the upper part of said frame, • a part (4) movable relative to said base so as to be able to be positioned by the occupant of said seat in a plurality of adjustment positions, said part being provided with a receiving face (5) of a cushion, • a device for locking of said part in the chosen adjustment position, said device comprising a toothed wheel (6) rotatably mounted on a main axis (7), said wheel being connected to said part so that a displacement of said part by a adjustment position to the other causes a corresponding rotation of said wheel, said device further comprising means for locking the rotation of said wheel in at least one direction, said headrest being characterized in that : • said locking means comprises at least a first (8) and a second (9) latches mounted to rotate along secondary axes (10) parallel to said main axis, said latches each having a locking end (11) arranged to be able introduce between teeth of said wheel and block it in rotation, in order to put said latches in the locked position, • said first latch is provided with an actuating member (12) enabling it to be actuated in rotation towards a position of unlocking in which its locking end (11) moves away from said wheel, • said first latch has a bearing face (13a) on a sliding face (14a) provided on said second latch, said faces being supported one against the other by a spring means (22), said faces being shaped so that an actuation of one of said latches in rotation in one direction achieves an actuation in rotation of the other of said latches in the same direction, in order to ensure a coordinated placing of said latches in the locked or unlocked position, said spring means being further arranged so as to actuate said latches towards their locked position. 2. Headrest according to claim 1, characterized in that it further comprises a third latch (15) succeeding the second latch (9), said second latch comprising a bearing face (13b) on a sliding face (14b) provided on said third latch, in order to ensure a coordinated setting of all the latches (8,9,15) in the locked or unlocked position. 3. Headrest according to one of claims 1 or 2, characterized in that it comprises at least four similar latches 8,9,15,16,17 distributed around the toothed wheel 6 according to a rotational symmetry, each of said latches comprising a bearing face 13a, 13b on a sliding face 14a, 14b provided on one of said latches succeeding it, in order to ensure a coordinated placing of all said latches in the locked or unlocked position. 4. Headrest according to any one of claims 1 to 3, characterized in that the teeth of the toothed wheel (6) have a geometry arranged so that the locking means in the locking configuration blocks the rotation of said wheel in the direction corresponding to a retreat of the movable part (4) and does not block said rotation in the direction corresponding to an advance of said movable part. 5. Headrest according to any one of claims 1 to 4, characterized in that: • the movable part (4) is mounted in longitudinal sliding relative to the base (3), so that it can be positioned in a plurality of adjustment positions by application of a longitudinal force applied manually by a user to said part mobile, • said headrest comprises at least one endless screw (18) extending along the main axis (7), said screw being mounted in rotation on said mobile part, said screw being received in a threaded orifice (19 ) produced in said base, said screw having at least one thread inclined relative to said axis so as to allow sliding of said movable part by application of said longitudinal force, 5 "the toothed wheel (6) is integral with one of the ends of said screw so as to rotate with said screw about said axis.