FR3062611A1 - HEADREST FOR THE SEAT OF A MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a headrest (1) comprising: a connection armature to a seat back; a casing (4) of energy absorption mounted movably on said frame so as to be adjustable in height and provided with a front face of receiving the head of a passenger; an electric motor cooperating with at least one driving portion (3) integral with said armature, said motor being coupled to a speed reducer so as to form a geared motor (10), said geared motor being mounted in said housing so as to be able to debating in translation to maintain its nominal position relative to said drive portion independently of the dimensional variations of said housing, said headrest further comprising a spring means for actuating said gear motor to said nominal position.

Description

® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY © Publication number:

(to be used only for reproduction orders)

©) National registration number

062 611

50917

COURBEVOIE © Int Cl ⁸ : B 60 N 2/829 (2017.01)

PATENT INVENTION APPLICATION

A1

©) Date of filing: 03.02.17. (© Applicant (s): CERA TSC Société par actions simpli- (© Priority: trusted - FR. @ Inventor (s): GEORGES LAURENT. ©) Date of public availability of the request: 10.08.18 Bulletin 18/32. ©) 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.

Pty MOTOR VEHICLE SEAT SUPPORT.

FR 3 062 611 - A1 _ The invention relates to a headrest (1) comprising: a frame connecting to a seat back; an energy absorption box (4) movably mounted on said frame so that it can be adjusted in height and provided with a front face for receiving the head of a passenger; an electric motor cooperating with at least one drive part (3) integral with said frame, said motor being coupled to a speed reducer so as to form a geared motor (10), said geared motor being mounted in said housing so as to be able wrestling in translation to maintain its nominal position relative to said drive part independently of the dimensional variations of said housing, said headrest further comprising a spring means for actuating said reduction motor towards said nominal 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 connection frame to a back of said seat, • a molded plastic material absorption of energy absorption in the event of impact of the head of a passenger on said headrest, said box being movably mounted on said frame so as to be able to be adjusted in height with respect to said frame, said case being provided with a front face for receiving the head of a passenger, said face being in particular dressed by a cushion, • an electric motor mounted integrally with said case, said motor cooperating with at least one drive part integral with said frame so as to allow the height adjustment of said housing.

The use of such an engine significantly increases the weight of the headrest, as well as its size and cost.

In addition, with such an arrangement, the positioning of the motor relative to the drive part may vary from its nominal position, this due to dimensional fluctuations of said housing resulting from temperature differences, and where appropriate dimensional manufacturing dispersions.

Indeed, by its nature in plastic material, generally based on polyethylene, the case is subject to strong dimensional variations in the temperature range of use of a vehicle.

Variations in the position of the motor then lead to non-repeatable operation of the headrest, depending on the conditions of use, when it is actuated in adjustment, which may in particular result in parasitic noise observed during said adjustment.

In addition, in the event of a passenger's head impact on the headrest, the dynamic energy absorption behavior of the box is affected by the fact that the motor is associated with it, which can present a risk for said passenger.

The object of the invention is to overcome these drawbacks.

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

• an armature connecting to a back of said seat, • a casing made of molded plastic material for absorbing energy in the event of an impact by the head of a passenger on said headrest, said casing being mounted movably on said so as to be able to be adjusted in height relative to said frame, said housing being provided with a front face for receiving the head of a passenger, • an electric motor mounted integrally with said housing, said motor cooperating with at least one part 'drive integral with said frame so as to allow height adjustment of said housing, said headrest further having the following characteristics:

• said motor is coupled to a speed reducer so as to form a gearmotor, said gearmotor being mounted in said housing so as to be able to debate in translation to maintain its nominal position relative to said drive part independently of the dimensional variations of said housing , • it further comprises a spring means for actuating said gear motor towards said nominal position.

In this description, the terms of positioning in space (top, bottom, longitudinal, transverse, front, top, etc.) are taken with reference to a headrest mounted in the vehicle in use.

It is specified here that a geared motor comprises an electric motor and a speed reducer, said reducer being able in particular to include a gear train making it possible to gear down the rotation of the motor.

The use of a gearmotor has the advantage of allowing the use of a low power motor, and therefore of low weight, size and cost, with a direct impact in terms of weight, size and cost on the support. -head.

With the proposed arrangement, due to the fact that the gearmotor is mounted in the housing being able to debate in sliding with respect to said housing, the dimensional variations of said housing have no influence on the positioning of said gearmotor with respect to the part of drive, said positioning being provided by the spring means which always places said gearmotor in nominal position.

This guarantees repeatable operation of the headrest when it is actuated in adjustment, this under all conditions of use.

In addition, in the event of a collision of the head of a passenger on the headrest, the dynamic behavior in energy absorption of the box is not affected by the presence of the gearmotor, since the latter is decoupled from said box, which improves the safety of said passenger.

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 front view of a headrest according to one embodiment, • Figure 2 is a partial schematic view according to a first perspective of the headrest of Figure 1, • Figure 3 is a detailed view from a view angle similar to that of FIG. 2, • FIG. 4 is a partial schematic view according to a second perspective of the headrest of FIG. 1, • FIG. 5 is a partial schematic view of detail in perspective of the appuitête of figure 1.

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

• a connecting frame to a back of said seat, • a casing 4 of molded plastic material for absorbing energy in the event of a passenger's head impacting on said headrest, said casing being movably mounted on said frame so as to be able to be adjusted in height with respect to said frame, said case being provided with a front face for receiving the head of a passenger, said face being in particular dressed by a cushion not shown, • an electric motor mounted integrally to said housing, said motor cooperating with at least one drive part 3 integral with said frame so as to allow the height adjustment of said housing, said headrest further having the following characteristics:

• said motor is coupled to a speed reducer so as to form a gearmotor 10, said gearmotor being mounted in said housing so as to be able to debate in translation to maintain its nominal position relative to said drive part independently of the dimensional variations of said case, • it further comprises a spring means for actuating said gear motor towards said nominal position.

According to the embodiment shown, the geared motor 10 is located in the lower part of the housing 4, so as to be located below the head of a passenger in the seat.

In this way, the passenger's head does not impact the headrest cushion 1 directly above the gearmotor 10, which is favorable to its safety.

According to the embodiment shown, the headrest 1 also has the following characteristics:

• the frame comprises two parallel metal branches 2 connecting to the seat back, said branches each being provided with a rack 3 forming a drive part, • the geared motor 10 rotates two transverse rods 11 each provided with a pinion 12 end meshing with the corresponding rack 3, • the mounting of said gearmotor on said housing is done by means of a pair of mounting bearings 13 mounted in longitudinal movement in said housing, said bearings each having a first conduit 14 slidingly receiving a respective branch 2, • said gearmotor is fixedly associated in the middle part of a transverse cross member 15, the end parts of said cross member being associated with said bearings, so that said gearmotor can debate in longitudinal translation, • the spring means comprises two respective actuating springs 17 said mounting bearings for bringing each pinion 12 into meshing towards the corresponding rack 3.

Such an arrangement makes it possible to achieve a particularly controlled height adjustment, this due to the fact that the two branches 2 are used symmetrically in said adjustment.

According to the embodiment shown, the end parts of the cross member 15 are associated with the mounting bearings 13 by slidingly being inserted in a respective second conduit 16 provided in each of said mounting bearings, so that the gearmotor 10 is longitudinally fixed by relative to said mounting bearings, said cross member being blocked in transverse translation by a locking means, said locking means being for example in the form of two caps, not shown, fixed at the ends of said cross member.

According to the embodiment shown, the headrest 1 further comprises a pair of top bearings 5 and a pair of bottom bearings 6 mounted by interlocking in respective housings provided in the housing 4, said housings being arranged so as to allow a clearance transverse of said bearings relative to said housing on either side of a respective nominal position, said clearance making it possible to absorb the transverse dimensional variations of said housing, said bearings being each provided with an orifice 9 slidingly receiving the corresponding branch 2, the mounting bearings 13 being arranged between said corresponding upper and lower bearings.

According to the embodiment shown, the racks 3 are arranged in the upper part of the branches 2, so as to remain hidden by the housing 4 when it is adjusted in the maximum-high position.

According to the embodiment shown, the mounting bearings 13 have a bearing surface 18 bearing against the branches 2 under the effect of the actuating springs 17, said surface being arranged so that the corresponding pinion 12 is kept slightly apart from the corresponding rack 3 relative to the position it would take in the absence of said surface, which makes it possible to minimize the noise produced during the adjustment maneuvers.

According to the embodiment shown, the first conduits 14 are in the form of trenches, the branches 2 being confined in each of said trenches by a respective pin 19.

Such an arrangement allows the branches 2 to be held firmly in the trenches in the event of an impact applied to the headrest 1.

According to the embodiment shown, the racks 3 are integrated into sleeves 20 of molded plastic material overmolding the branches 2.

According to the embodiment shown, the racks 3 open forward.

Such an arrangement makes it possible, in the event of a collision of the head of a passenger on the cushion, to go in the direction of engagement of the pinions 12 in the direction of the racks 3, this making it possible to guarantee a favorable blocking in height of the housing 4 to the safety of said passenger.

According to the embodiment shown, the branches 2 are tubular, the upper ends of said branches being connected to each other by a tubular metallic spacer 21 fitting together with said ends.

According to one embodiment, the geared motor 10 is arranged so that the housing 4 can also be actuated manually in height adjustment, this by pressing exerted upwards or downwards on said housing by a passenger.

In addition, the gearmotor 10 can be dimensioned so as to deform plastically, in particular by twisting the rod forming part of it, to self-lock in the event of a violent impact applied by the head of a passenger on the headrest 1, which keeps the housing 4 in its adjustment position in such a situation and thus contributes to the safety of said passenger.

Finally, it will be mentioned that this principle of combining a decoupling of the geared motor 10 relative to the housing 4 and of a spring means bringing said geared motor into nominal position can be applied to a wide variety of arrangements, for example in the case a geared motor 10 actuating in rotation a threaded rod cooperating with a threaded orifice secured to the frame.

Claims (10)

1. Headrest (1) of a motor vehicle seat, said headrest comprising: • a connection frame to a back of said seat, • a casing (4) of molded plastic material for absorbing energy in the event of a passenger's head impacting on said headrest, said casing being mounted movably on said frame so as to be able to be adjusted in height with respect to said frame, said case being provided with a front face for receiving the head of a passenger, • an electric motor mounted integrally with said case, said motor cooperating with at least a drive part (3) integral with said frame so as to allow the height adjustment of said case, said headrest being characterized in that: • said motor is coupled to a speed reducer so as to form a gearmotor (10), said gearmotor being mounted in said housing so as to be able to debate in translation in order to maintain its nominal position relative to said drive part independently of variations dimensional of said box, • it further comprises a spring means for actuating said gear motor towards said nominal position. 2. headrest (1) according to claim 1, characterized in that the gear motor (10) is located in the lower part of the housing (4), so as to be located below the head of a passenger in the seat . 3. Headrest (1) according to any one of claims 1 or 2, characterized in that it also has the following characteristics: • the frame comprises two parallel metal branches (2) connecting to the seat back, said branches each being provided with a rack (3) forming a drive part, • the gearmotor (10) rotates two rods (11 ) transverse each provided with a pinion (12) end meshing with the corresponding rack (3), • the mounting of said gearmotor on said housing is done by means of a pair of mounting bearings (13) mounted in longitudinal travel in said housing, said bearings each having a first conduit (14) slidingly receiving a respective branch (2), • said gearmotor is fixedly associated in the middle part of a transverse crosspiece (15), the end parts of said cross member being associated with said bearings, so that said gearmotor can debate in longitudinal translation, • the spring means comprises two springs (17) respe ctifs of actuation of said mounting bearings to bring each pinion (12) meshing towards the corresponding rack (3). 4. Headrest (1) according to claim 3, characterized in that the end parts of the crosspiece (15) are associated with the mounting bearings (13) by slidingly inserting into a second conduit (16) respective provided in each of said mounting bearings, so that said gearmotor is longitudinally fixed with respect to said mounting bearings, said cross member being blocked in transverse translation by a locking means. 5. Headrest (1) according to any one of claims 3 or 4, characterized in that it further comprises a pair of high bearings (5) and a pair of low bearings (6) mounted by interlocking in respective housings provided in the housing (4), said housings being arranged so as to allow a transverse clearance of said bearings relative to said housing on either side of a respective nominal position, said clearance making it possible to absorb the transverse dimensional variations of said housing , said bearings being each provided with an orifice (9) slidingly receiving the corresponding branch (2), the mounting bearings (13) being arranged between said corresponding upper and lower bearings. 6. headrest (1) according to any one of claims 3 to 5, characterized in that the racks (3) are arranged in the upper part of the branches (2), so as to remain hidden by the housing (4) when it is set in the maximum-high position. 7. Headrest (1) according to any one of claims 3 to 6, characterized in that the mounting bearings (13) have a bearing surface (18) bearing against the branches (2) under the effect of the actuating springs (17), said surface being arranged so that the corresponding pinion (12) is kept slightly apart from the corresponding rack (3) relative to the position it would assume in the absence of said surface . 8. Headrest (1) according to any one of claims 3 to 7, characterized in that the first conduits (14) are in the form of trenches, the branches (2) being confined in each of said trenches by a pin (19) respectively. 9. Headrest (1) according to any one of claims 3 to 8, characterized in that the racks (3) are integrated into sleeves (20) of molded plastic material 10 overmolding the branches (2). 10. Headrest (1) according to any one of claims 3 to 9, characterized in that the racks (3) open out towards the front. 1/4