Motor vehicle seat headrest
A compact actuation system with parallel and staggered transverse axes toothed wheels addresses the space occupancy issue in motor vehicle seat headrests, enabling adjustable headrests with minimized thickness and height.
Patent Information
- Application Number
- FR2022004995
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2022-02-14
- Filing Date
- 2022-05-24
- Publication Date
- 2025-11-28
- Estimated Expiration
- 2042-05-24
AI Technical Summary
Existing motor vehicle seat headrests with speed reducers occupy significant vertical and longitudinal space, making it difficult to achieve minimized thickness and height, which is incompatible with compact design requirements.
A compact actuation system using toothed wheels or pairs of toothed wheels with parallel and staggered transverse axes, forming a speed reducer that minimizes vertical and longitudinal extension, allowing for a compact design.
The compact actuation system enables an electrically adjustable headrest with controlled thickness and height, optimizing space utilization and reducing the motor's size, weight, and cost.
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Abstract
Description
Title of the invention: Motor vehicle seat headrest
[0001] The invention relates to a motor vehicle seat headrest.
[0002] It is known to produce a motor vehicle seat headrest, said headrest comprising: a metal frame connecting to a backrest of said seat, a block mounted to slide relative to said frame, so as to allow its adjustment,
[0003] said headrest further comprising an actuation system for said block, said system comprising: a motor equipped with a gear element driven in rotation about the axis of said motor, a rotary transmission means meshing with a reciprocating means for actuating said block, a speed reducer interposed between said gear element and said transmission means.
[0004] This provides an adjustable headrest, in particular at least in height and possibly longitudinally.
[0005] Having a speed reducer makes it possible to minimize the power of the motor used - and therefore its weight, cost and size.
[0006] However, such a speed reducer itself occupies space, said space being all the more important as the motor is of low power.
[0007] However, providing such a space usually requires significant vertical and longitudinal dimensions, which is difficult to reconcile with having headrests of minimized thickness and height.
[0008] The invention aims to provide an electrically adjustable headrest with controlled thickness and height.
[0009] To this end, the invention proposes a headrest for a motor vehicle seat, said headrest comprising: a metal frame connecting to a backrest of said seat, a block mounted to slide relative to said frame, so as to allow its adjustment,
[0010] said headrest further comprising an actuation system for said block, said system comprising: a motor equipped with a gear element driven in rotation about the axis of said motor, a rotary transmission means meshing with a reciprocal means for activate said block, • a speed reducer interposed between said gear element and said transmission means,
[0011] said reducer being formed exclusively of toothed wheels or pairs of toothed wheels, the wheels of said pairs being coaxial and of different diameter, the axes of rotation of said wheels or pairs of wheels being parallel and staggered transversely, so that said system forms a compact actuation system.
[0012] In this description, the terms of positioning in space (front, height, longitudinal, transverse, vertical, ...) are taken with reference to the headrest arranged in the situation of use in the vehicle.
[0013] When it is said that the axes of rotation of the wheels or pairs of wheels are parallel and staggered transversely, this means that, starting from the gear element, said wheels or pairs of wheels shift transversely as successive meshings occur.
[0014] With the proposed arrangement, the speed reducer extends essentially transversely - and little vertically and longitudinally - that is to say in the direction in which there is usually more available space than in other directions.
[0015] Other features and advantages of the invention will become apparent from the following description, made with reference to the accompanying figures, in which:
[0016] [Fig-1] is a schematic, partially exploded perspective view of a headrest equipped with two adjustable blocks depending on the design,
[0017] [Fig.2] is a schematic perspective view, according to one embodiment, of two compact actuation systems for the blocks of a headrest, said headrest being provided with two adjustable blocks, in accordance with that shown in [Fig. 1], the reciprocal means of each of said systems being shown in two extreme adjustment positions,
[0018] [Fig.3] is a schematic principle perspective view of a speed reducer for a compact actuation system according to a specific embodiment,
[0019] [Fig.4] is a schematic perspective view, according to an alternative embodiment, of a compact actuation system for a first height-adjustable block,
[0020] [Fig.5] is a schematic perspective view, according to another embodiment al alternative, of a compact actuation system of a second longitudinally adjustable block.
[0021] With reference to the figures, a headrest 1 of a motor vehicle seat is described, said headrest comprising: • a metal frame 2 for connecting to a backrest of said seat, • a block 3,4 mounted to slide relative to said frame, so as to to allow its adjustment,
[0022] said headrest further comprising an actuation system 5 of said block, said system comprising: • a motor 6 provided with a gear element 7 - in particular in the form of a worm gear, according to the embodiment shown, or a toothed wheel, according to an embodiment not shown - driven in rotation about the axis 8 of said motor, • a rotating transmission means 9 meshing with a reciprocating means 10 for actuating said block, • a speed reducer 11 interposed between said gear element and said transmission means, said reducer being formed exclusively of toothed wheels 12 or pairs of toothed wheels 13, the wheels of said pairs being coaxial and of different diameter, the axes of rotation 14 of said wheels or pairs of wheels being parallel and staggered transversely - according to the direction 15 as represented -, so that said system forms a compact actuation system.
[0023] According to an embodiment not shown, the headrest 1 comprises a single block 3,4 mounted to slide vertically on the frame 2 so as to be height adjustable, said block being actuated by the compact actuation system 5.
[0024] In particular, the motor 6 of this system can be mounted so that its axis 8 extends transversely, in order to minimize its size in the vertical and longitudinal directions.
[0025] According to one embodiment, as illustrated in Figures 1 and 2, the headrest 1 comprises: • a first block 3 mounted to slide vertically on the frame 2, so as to be adjustable in height, • and a second block 4 mounted to slide longitudinally on said first block, so as to be longitudinally adjustable, said second block having a front face 16 for receiving the head of a seat occupant, said face being notably covered with a cushion not shown,
[0026] at least one of said blocks being actuated by a compact actuation system 5.
[0027] According to this embodiment shown: • The first block 3 is actuated by a first compact actuation system 5 and the second block 4 is actuated by a second compact actuation system 5, • The motors 6 of said systems are mounted so that their axes 8 are parallel and extend transversely, • the axes of rotation 14 of the wheels 12 or pairs of wheels 13 of said first system extend along a first direction 17 and the axes of rotation 14 of the wheels 12 or pairs of wheels 13 of said second system extend along a second direction 18 distinct from said first direction.
[0028] Such an arrangement allows the actuation systems 5 to be nested one inside the other and minimizes the overall size.
[0029] According to the embodiment shown, the first direction 17 is orthogonal to the second direction 18.
[0030] According to various embodiments, when the first block 3 is actuated by a compact actuation system 5, the transmission means 9 is: • according to the embodiment shown in [Fig.2], a worm screw mounted for rotation on said first block, said screw meshing with a nut fixed to the frame to form a reciprocal means 10, • according to an unrepresented variant, a nut mounted for rotation on said first block, said nut meshing with a worm screw fixed to the frame to form a reciprocal means 10.
[0031] According to the embodiment of [Fig.4], the first block 3 is actuated by a compact actuation system 5, given that: • The frame 2 comprises two parallel branches 19, spaced apart transversely, • the reducer 11 meshes with the transmission means 9 via a first right-angle gear 20 - in particular of 45° -, said gear being part of an extreme pair of gears 21 arranged at the end of said reducer furthest from the motor 6, • said transmission means is in the form of a transverse rotating shaft 22 provided with a second right-angle gear 23 cooperating with said first gear, said shaft being further provided with two pinions 24 spaced transversely apart from each other, • the reciprocal means 10 is formed by two racks 25 extending respectively along each of the said branches, each of the said pinions engaging with one of the said respective racks to actuate the said first block in sliding.
[0032] According to various embodiments, a rack 25 is produced: • either directly in branch 19, as shown in [Fig.4], • either, according to an embodiment not shown, in a molded plastic material sleeve surrounding the branch 19, said sleeve being fitted onto said branch or overmolding it.
[0033] According to various embodiments, when the second block 4 is actuated by a compact actuation system 5, the transmission means 9 is: • according to the embodiment shown in [Fig.2], a worm screw mounted for rotation on the first block 3, said screw meshing with a nut fixed to said second
[0034]
[0035] block to form reciprocal means 10, • according to an unrepresented variant, a nut mounted for rotation on said first block, said nut meshing with a worm screw fixed to said second block to form reciprocal means 10. According to the embodiment in [Fig. 5], the second block 4 is actuated by a compact actuation system 5, given that: • the reducer 11 meshes with the transmission means 9 via a first right-angle gear 20 - in particular of 45° -, said gear being part of an extreme pair of gears 21 arranged at the end of said reducer furthest from the motor 6, • said transmission means is in the form of a rotating shaft 22 extending transversely, said shaft being provided with a second right-angle gear 23 cooperating with said first gear, said shaft being further provided with at least one pinion 24, • the reciprocal means 10 comprises at least one rack 25 extending longitudinally along said second block, said pinion meshing with said rack to actuate said second block in sliding motion. According to one embodiment, as illustrated in Figures 1 and 4, the armature 2 comprises two parallel arms 19 separated from each other transversely. Advantageously, as illustrated in [Fig. 4], at least one compact actuation system 5 is housed between the arms 19; indeed, the space available between said arms is generally well suited for housing such a system.
Claims
Demands
1. Headrest (1) for a motor vehicle seat, said headrest comprising: • a metal frame (2) for connection to a backrest of said seat, • a block (3, 4) mounted to slide relative to said frame, so as to allow its adjustment, said headrest further comprising an actuation system (5) for said block, said system comprising: • a motor (6) provided with a gear element (7) driven in rotation about the axis (8) of said motor, • a rotary transmission means (9) meshing with a reciprocating means (10) for actuating said block, • a speed reducer (11) interposed between said gear element and said transmission means, said headrest being characterized in that: • said reducer is formed exclusively of toothed wheels (12) or pairs of toothed wheels (13), the wheels of said pairs being coaxial and of different diameters,the axes of rotation (14) of said wheels or pairs of wheels being parallel and arranged transversely, so that said system forms a compact actuation system.
2. Headrest according to claim 1, characterized in that it comprises a single block (3) mounted to slide vertically on the frame (2) so as to be height adjustable, said block being actuated by the compact actuation system (5).
3. Headrest according to claim 1, characterized in that it comprises: • a first block (3) mounted to slide vertically on the frame (2), so as to be height-adjustable, • and a second block (4) mounted to slide longitudinally on said first block, so as to be longitudinally adjustable, said second block having a front face (16) for receiving the head of a seat occupant, at least one of said blocks being actuated by a compact actuation system (5).
4. Headrest according to claim 3, characterized in that: • the first block (3) is actuated by a first compact actuation system (5) and the second block (4) is actuated by a second compact actuation system (5), • the motors (6) of said systems are mounted so that their axes (8) are parallel and extend transversely, • the axes of rotation (14) of the wheels (12) or pairs of wheels (13) of said first system extend in a first direction (17) and the axes of rotation (14) of the wheels (12) or pairs of wheels (13) of said second system extend in a second direction (18) distinct from said first direction.
5. Headrest according to the preceding claim, characterized in that the first direction (17) is orthogonal to the second direction (18).
6. Headrest according to any one of claims 2 to 5, characterized in that the first block (3) is actuated by a compact actuation system (5) the transmission means of which (9) is: • either a worm screw mounted for rotation on said first block, said screw meshing with a nut fixed to the frame (2) to form a reciprocal means (10), • or a nut mounted for rotation on said first block, said nut meshing with a worm screw fixed to the frame (2) to form a reciprocal means (10).
7. Headrest according to any one of claims 2 to 5, characterized in that the block (3) is actuated by a compact actuation system (5), whereas: • the armature (2) comprises two parallel branches (19) separated from each other transversely; • the reducer (11) meshes with the transmission means (9) by means of a first right-angle gear (20), said gear being part of an extreme pair of gears (21) arranged at the end of said reducer furthest from the motor (6); • said transmission means is in the form of a transverse rotating shaft (22) provided with a second right-angle gear (23) cooperating with said first gear, said shaft being further provided with two pinions (24) separated transversely from each other; • the reciprocal means (10) is formed by two racks (25) extending respectively along each of said branches, each of said pinions meshing with one of said respective racks to actuate said first block in sliding motion.
8. Headrest according to any one of claims 3 to 5, characterized in that the second block (4) is actuated by a compact actuation system (5) the transmission means of which (9) is: • either a worm screw mounted for rotation on the first block (3), said screw meshing with a nut fixed to said second block to form a reciprocal means (10), • or a nut mounted for rotation on said first block, said nut meshing with a worm screw fixed to said second block to form a reciprocal means (10).
9. Headrest according to any one of claims 3 to 5, characterized in that the second block (4) is actuated by a compact actuation system (5), wherein: • the reducer (11) meshes with the transmission means (9) by a first right-angle gear (20), said gear being part of an extreme pair of gears (21) disposed at the end of said reducer furthest from the motor (6), • said transmission means is in the form of a rotating shaft (22) extending transversely, said shaft being provided with a second right-angle gear (23) cooperating with said first gear, said shaft being further provided with at least one pinion (24), • the reciprocal means (10) includes at least one rack (25) extending longitudinally along said second block, said pinion meshing with said rack to actuate said second block in sliding motion.
10. Headrest according to any one of the preceding claims, characterized in that the frame (2) comprises two parallel arms (19) separated from each other transversely, at least one compact actuation system (5) being housed between said arms.