FR3079465A1 - PNEUMATIC-CONTROLLED BACK UP FILE ADJUSTMENT DEVICE FOR VEHICLE SEAT, VEHICLE SEAT BACK, AND VEHICLE SEAT COMPRISING SUCH A HEADREST - Google Patents

Abstract

The invention relates to a rear seat adjustment device (40) for a vehicle seat (10), the vehicle seat (10) comprising a backrest frame (17), the backrest adjustment device ( 40) comprising: a headrest support (64) for receiving a headrest, the headrest support (64) being adapted to be pivotally mounted about a transverse axis (Y 1), relative to the backrest frame (17) of the vehicle seat (10), and - an inflatable pocket (80) intended to be interposed between the headrest support (64) and the backrest frame (17). ) such that inflating or deflating the inflatable bag (80) causes rotation of the headrest support (64) relative to the backrest frame (17).

Description

PNEUMATICALLY CONTROLLED TOP BACK ADJUSTMENT DEVICE FOR VEHICLE SEAT, VEHICLE SEAT BACKREST, AND VEHICLE SEAT HAVING SUCH A HEADREST

Field

The present invention relates to a high backrest adjustment device for a vehicle seat, to a vehicle seat backrest comprising such a high seat adjustment device and to a motor vehicle seat comprising such a backrest.

Presentation of the prior art

To improve the comfort of the occupant of a car seat, the seat can have several adjustments allowing it to be better adapted to the morphology of the occupant. Thus, the position of the seat can be adjusted relative to the steering wheel, depending on the size of the occupant. The seat back may be more or less reclining relative to the seat. The seat can also be fitted with a headrest, the height position of which, relative to the seat back, can be adjusted by the occupant.

More recently, head restraints have appeared such that the position of the occupant's head support zone on the head restraint can be modified. To do this, the headrest in question comprises a frame and a part that is movable relative to the frame, in a longitudinal direction of the seat. However, to obtain a satisfactory adjustment range, it is then necessary to make the relatively thick headrest (in the longitudinal direction of the seat). This thickness affects the aesthetics of the headrest and seat in general. In addition, the distance between the head support area and the backrest frame is increased. This increases the risk of trauma to the cervical spine ("whiplash") in the event of a shock, particularly in the event of a rear impact.

Summary of the invention

The object of the present invention is in particular to propose a device making it possible to adjust the position of the headrest which does not have the drawbacks of the prior art.

To this end, the invention provides a device for adjusting the top of the backrest for a vehicle seat, the vehicle seat comprising a backrest frame, the device for adjusting the top of the backrest comprising:

a headrest support intended to receive a headrest, the headrest support being intended to be pivotally mounted about a transverse axis, relative to the backrest frame of the vehicle seat, and

- an inflatable pocket intended to be interposed between the headrest support and the back frame so that inflation or deflation of the inflatable pocket causes the headrest support to rotate relative to the backrest frame.

A backrest adjustment device makes it possible to move in a substantially longitudinal direction of the seat, an upper part of the backrest, independently of the lower part of the backrest, to define a contact area (or support area) between the backrest - and more precisely the high-back adjustment device - and the occupant of the vehicle seat - and in particular the shoulder blades, the shoulders and / or the part of the back between the shoulder blades and / or the shoulders.

Thus, according to the invention, to adjust the longitudinal position of the headrest, the latter is mounted on a headrest support of a backrest adjustment device, the headrest support pivoting about a transverse axis, relative to the seat back and in particular to the frame of the seat back. Rotating the headrest adjusts the position of the occupant's head support area on the headrest, in the longitudinal direction of the seat. It is thus possible to design a more compact and / or more aesthetic headrest.

The headrest support may also have a support surface for the upper back of an occupant of the vehicle seat. The backrest adjustment device thus provides its support function for the upper part of the back of a seat occupant by means of the headrest support. In addition, thus, the distance between the support area of the head and the support area of the back is kept reduced. This limits the risk of trauma to the cervical spine in the event of an impact, particularly in the event of a rear impact.

Finally, the inflatable pocket used to move the headrest support advantageously absorbs frontal impacts, especially rear impacts, in a manner substantially analogous to an airbag.

In preferred embodiments, the backrest adjustment device according to the invention has one or more of the following characteristics, taken alone or in combination:

- The backrest adjustment device comprises a frame, intended to be fixed to the backrest frame of the vehicle seat, the inflatable pocket being interposed between the headrest support and the frame;

- The backrest adjustment device further comprises a ratchet device, for locking in an angular position relative to the transverse axis of the headrest support;

- The backrest adjustment device further comprises two connecting rods, each connecting rod being pivotally mounted about an axis perpendicular to the transverse axis relative to the headrest support, at a first end, and relative to the back frame or frame, at a second end;

- A toothed wheel is integral in rotation with the end of at least one of the two connecting rods, a pawl being biased elastically in the position for blocking the rotation of the toothed wheel in a direction of rotation of the toothed wheel;

- the backrest adjustment device further comprises at least one second inflatable pocket such that an inflation of the second inflatable pocket moves the pawl to a gear wheel release position;

- The headrest support comprises at least one housing, preferably two housing for receiving a headrest pin;

- The backrest adjustment device further comprises a headrest, the headrest being mounted on the headrest support, the headrest preferably being fixed on the headrest support ;

- The headrest has at least one pin received in said at least one housing, the headrest preferably having two pins, for example monoblocks, each received in a pin receiving housing of the headrest support .

According to another aspect, the invention also relates to a vehicle seat back comprising a back frame and a high back adjustment device as described above in all its combinations, the headrest support being mounted on the back frame, via the frame if necessary, so that the headrest support is pivotable about the transverse axis, relative to the back frame.

According to yet another aspect, the invention relates to a vehicle seat comprising a seat with a seat frame, a backrest as described above in all its combinations, the back frame is preferably pivotally mounted around an axis transverse to the seat frame.

Brief description of the drawings

Other characteristics and advantages of the invention will appear on reading the following description of one of its embodiments, given by way of nonlimiting example, with reference to the accompanying drawings, in which:

FIG. 1 schematically represents a side view of a vehicle seat provided with an example of a backrest adjustment device,

FIGS. 2 and 3 represent, from two opposite perspectives, the device for adjusting the backrest with which the vehicle seat of FIG. 1 is fitted, in a first position,

FIG. 4 represents a partial top view of the device for adjusting the backrest, in the first position of FIGS. 2 and 3,

FIG. 5 is a view similar to FIG. 4, of the device for adjusting the backrest in a second position,

- Figure 6 shows in perspective the backrest adjustment device in the second position, seen from the front.

Detailed description of the invention

In the various figures, the same references designate identical or similar elements. For the sake of brevity, only the elements which are useful for understanding the embodiment described are shown in the figures and are described in detail below.

In the following description, when reference is made to qualifiers of absolute position, such as the terms "front", "rear", "top", "bottom", "left", "right", etc., or relative, such as the terms "above", "below", "upper", "lower", etc., or to qualifiers of orientation, such as "horizontal", "vertical", etc., it is made reference, unless otherwise specified, to the orientation of the figures or of a seat in its normal position of use.

FIG. 1 schematically represents a motor vehicle seat 10 mounted on a slide mechanism 12.

In the following, the longitudinal direction X means the longitudinal direction of the seat. The longitudinal direction of the seat is considered to be the same as the longitudinal direction of the motor vehicle in which the seat is mounted. This longitudinal direction X corresponds to the normal direction of advance of the vehicle. The transverse direction Y is the transverse direction of the seat. The transverse direction of the seat thus corresponds to the transverse or lateral direction of the motor vehicle. This transverse direction corresponds to a direction perpendicular to the normal direction of advance of the vehicle. Finally, the vertical direction Z is a vertical direction of the seat, perpendicular to the longitudinal and transverse directions.

The seat 10 comprises a seat 14, with a seat frame 15, on which a backrest 16, with a backrest frame 17, is mounted, generally pivoting about a transverse axis 18 by an articulation mechanism 20. The seat 14 is mounted on mobile profiles 22, also called slides or male profiles, by means of feet or crosspieces 24, 26. Each mobile profile 22 is part of a slide 12 and is associated with a fixed profile 30. The fixed profile 30 is also called rail or female profile. The fixed section 30 is fixed to the floor 32 of a motor vehicle. The seat 10 comprises in this example a manual control element 34, called a lifting beam, for sliding control of the slides 12. This manual control element 34 makes it possible in particular to block and unblock systems for stopping the sliding of the movable sections relative to the respective fixed profiles. Once the stop systems have been released, the manual control element 34 can also be used to slide the movable profiles 22 relative to their respective fixed profiles 30 of the slide 12 in the longitudinal direction X of the slides 12. The profiles fixed 30 and mobile 22 of the slides 12 are generally metallic.

The seat 10 also includes a headrest 36.

In the following, the mounting of the headrest 36 on the backrest 16 is described in more detail by means of a backrest adjustment device 40.

The backrest adjustment device 40 is able to be moved relative to the backrest frame 17 in order to adjust, in particular longitudinally, the position of a support area of the upper back of the seat occupant on the backrest adjuster 40.

The high back adjuster 40 includes a frame 42 fixed to the back frame 17 of the vehicle seat 10. For example, this frame 42 can be screwed or riveted to the back frame 17. Other modes fixing the frame 42 on the back frame 17 are conceivable. The frame 42 is not shown in FIGS. 4 and 5.

The backrest frame 17 advantageously comprises two uprights and at least one high cross member. The backrest frame 17 may further comprise a low cross member and / or a second high cross member.

The frame 42 defines first and second shaft receiving holes 44, 46 extending along axes Zl, Z2 parallel and substantially perpendicular to the transverse direction Y. A toothed wheel 48, 50 is fixed on each shaft 44, 46 which cooperates with a respective pawl 52, 54. An arm 56, 58 (or connecting rod) is also mounted integral in rotation on each shaft 44, 46. The pawls are elastically constrained in their locking position of the corresponding toothed wheel 48, 50, thereby blocking the rotation of the arms 56 , 58. An airbag 60, 62 is provided to cooperate with a respective pawl 52, 54. In the example shown, the inflation of the airbag 60, 62 causes the rotation of the corresponding pawl 52, 54, in a release position of the corresponding toothed wheel 48, 50.

Furthermore, the backrest adjustment device 40 comprises a headrest support 64. This headrest support 64 has the shape of a shell, in particular a rigid shell compared to the covering. softer seat 10.

The headrest support 64 is rotatably mounted relative to the backrest frame 17 about a transverse axis Yl, parallel to the transverse direction Y. In the example illustrated, this rotary mounting of the support support- head 64 is produced substantially at the end of arms 64i, 642 lateral, extending substantially in a vertical direction from a part of the headrest support 64 on which the back of an occupant of the seat can come to bear. In the folded position of the headrest support 64, the top of the headrest support 64 is substantially at the same level as the top of the backrest frame 17. In this folded position of the headrest support 64 , the latter is disposed partly between the uprights of the back frame 17 and partly opposite (or opposite) the upper cross member of the back frame.

The headrest support 64 here forms two housings 66, 68 for receiving a pin 70, 72 of the headrest 36.

Furthermore, the two arms 56, 58 are also pivotally mounted relative to the headrest support 64 in a substantially vertical direction, in particular in a direction parallel to the axes Zl, Z2 of rotation of the shafts 44, 46. For example, each arm 56, 58 is rotatably mounted, at its end opposite to that mounted integral in rotation with the shaft 44, 46, around an axis parallel to the axis Zl, Z2 on a bearing 74, 76, received in a housing 78 formed by the headrest support 64. The housing 78 preferably prevents the relative rotation of the bearing 74, 76 relative to the headrest support 64 about an axis parallel to the axis Zl, Z2 . For example, each bearing 74, 76 has a substantially parallelepiped shape and the housing 78 is of section, rectangular or square, corresponding to the section of the bearing 74, 76.

Finally, an inflatable pocket 80 is interposed between the frame 42 and the appuitete support 64.

Thus, by inflating the inflatable pocket 80, the headrest support 64 is pivoted about the axis Yl. This is accompanied by a pivoting of the arms 56, 58 around the respective axis Zl, Z2. This rotation of the arms 56, 58 is possible because the toothed wheels 48, 50 have inclined teeth allowing rotation of the toothed wheel 48, 50 in one direction. Rotation in the opposite direction, which would correspond to bringing the headrest support 64 closer to the frame 42, is however prevented by the presence of the pawl 52, 54 and the shape of the teeth of the toothed wheel 48, 50.

It is understood that thus, when the headrest 36 is secured to the headrest support 64, it can be moved forwards or backwards in the longitudinal direction X. It is thus possible to adjust the position of the headrest 36 for better comfort of the occupant of the seat 10. In particular, FIGS. 5 and 6 illustrate the most advanced position of the headrest 36 and of the headrest support 64. It is however possible by inflating more or less the inflatable pocket 80, to adjust the position of the headrest 36 for better comfort of the occupant of the seat 10, according to substantially all the intermediate positions between the two extreme positions shown. It should be noted that maintaining the headrest support 64 in position can be achieved without the need for the inflatable pocket 80 to remain inflated. The two pawls 52, 54 can in fact allow this retention of the headrest support 64 in position. However, it can be envisaged to keep the inflatable pocket 80 inflated, so that it can absorb a possible shock.

It is also understood that the forward or backward movement of the headrest 36 is not a translational movement in the longitudinal direction. However, the inventors have found that it is possible, with the backrest adjustment device 40 described above, to make a longitudinal movement of the headrest 36 forwards or backwards with a sufficient stroke for comfortable adjustment, with limited vertical movement. In practice, this limited vertical movement is barely noticeable by the occupant of the seat 10, in particular because the appuitête 36 has a flexible, compressible lining. In addition, this vertical displacement of the headrest 36 can be compensated for by implementing a headrest 36 adjustable in height. Such a height-adjustable headrest is well known to those skilled in the art. It is therefore not written in more detail here. The height of the headrest 36 can in particular be adjusted by means of headrest pins 70, 72 of adjustable length and / or of a headrest 36 comprising a headrest frame and a plate d headrest movable relative to the headrest frame, in particular in a substantially vertical direction. To move the plate relative to the frame and / or to adjust the length of the headrest pins, an electric actuator can be used.

It can be noted that here the backrest adjustment device 40 consists of the headrest support 64, the frame 42, if any, and the mechanism for adjusting the angular position around the transverse axis Y2 of the support d headrest 64, relative to the frame 42, if any, or to the backrest frame 17. In other words, the headrest support 64 defines the area of contact with the upper part of the back of an occupant of the seat, contact zone whose position is adjusted by pivoting the headrest support 64 around the transverse axis Y2. Thus, the longitudinal position of the headrest 36, on the one hand, and the longitudinal position of the contact area of the upper part of the back of an occupant of the seat with the high backrest adjustment device 40, on the other hand, are settled concomitantly.

Of course, the invention is in no way limited to the embodiments described by way of illustration, without limitation.

Claims (11)

1. High back adjustment device (40) for a vehicle seat (10), the vehicle seat (10) comprising a back frame (17), the high back adjustment device (40) comprising: a headrest support (64) intended to receive a headrest, the headrest support (64) being intended to be pivotally mounted about a transverse axis (Yl), relative to the frame backrest (17) of the vehicle seat (10), and an inflatable pocket (80) intended to be interposed between the headrest support (64) and the backrest frame (17) so that inflation or deflating the inflatable pocket (80) causes the headrest support (64) to rotate relative to the back frame (17). 2. High back adjustment device according to claim 1, comprising a frame (42), intended to be fixed on the back frame (17) of the vehicle seat (10), the inflatable pocket (80) being interposed between the headrest support (64) and the frame (40). 3. High back adjustment device according to claim 1 or 2, further comprising a ratchet device, for locking in angular position relative to the transverse axis (Yl) of the headrest support (64). 4. High back adjustment device according to one of claims 1 to 3, further comprising two connecting rods (56, 58), each connecting rod (56, 58) being pivotally mounted about an axis perpendicular to the axis transverse (Yl) relative to the headrest support (64), at a first end, and relative to the back frame (17) or to the frame (42), at a second end. 5. High back adjustment device according to claims 3 and 4, wherein a toothed wheel (44; 46) is rotatably integral with the end of at least one of the two connecting rods (56; 58), a pawl (52; 54) being resiliently returned to the position for blocking the rotation of the toothed wheel (44; 46) in a direction of rotation of the toothed wheel (44; 46). 6. High back adjustment device according to claim 5, further comprising at least a second inflatable pocket (60; 62) such that an inflation of the second inflatable pocket (60; 62) displaces the pawl (52; 54 ) in a release position of the toothed wheel (44; 46). 7. High back adjustment device according to any one of the preceding claims, in which the headrest support (64) comprises at least one housing (66; 68), preferably two housings (66, 68) receiving a headrest pin (70; 72). 8. High back adjustment device according to any one of the preceding claims, further comprising a headrest (36), the headrest (36) being mounted on the headrest support (64) , the headrest (36) being preferably fixed on the headrest support (64). 9. High back adjustment device according to claims 7 and 8, wherein the headrest (36) has at least one pin (70; 72) received in said at least one housing (66; 68), l headrest (36) preferably having two pins (70, 72), for example monoblocks, each received in a pin receiving housing (66; 68) of the headrest support (64). 10. Vehicle seat backrest (10) comprising a backrest frame (17) and a backrest adjustment device according to any one of the preceding claims, the headrest support (64) being mounted on the 'back frame (17), via the frame (42) if necessary, so that the headrest support (64) is pivotable about the transverse axis (Y 1), relative to the back frame (17). 11. vehicle seat (10) comprising a seat (14) with a seat frame (15), a backrest (16) according to claim 10, the back frame is preferably pivotally mounted about a transverse axis relative to the seat frame.