WO2005068252A1

WO2005068252A1 - Improved head restraint

Info

Publication number: WO2005068252A1
Application number: PCT/SE2005/000049
Authority: WO
Inventors: Rune Karlberg; Therese Nilsson; Annica Andersson
Original assignee: Kongsberg Automotive Ab
Priority date: 2004-01-19
Filing date: 2005-01-19
Publication date: 2005-07-28
Also published as: SE0400086L; SE525947C2; SE0400086D0

Abstract

The invention relates to a head restraint (1) for use in motor vehicles and comprising a support (5) for supporting the head restraint and fixing the head restraint to the backrest of a vehicle seat. The support (5) comprises a carrier (14) and at least one support leg (16, 17) coupled to the carrier (14), together with an adjusting arrangement (6) for adjusting the position of the head restraint in relation to an occupant of the motor vehicle. The carrier (14) is enclosed by a casing (2), which is rotatably connected to the support (5) along an axis of rotation (20) running essentially at right angles to the support leg (16, 17). The adjusting arrangement (6) comprises a first locking plate (26) having a recess (21) designed to interact with a locking plate (24), firmly connected to the axis of rotation (20) and having locking elements (25) located successively and essentially radially around the axis of rotation and defining at least two separate locking positions for locking the position of the casing (2) around the axis of rotation. The adjusting arrangement furthermore comprises a second locking plate (33) comprising a locking tongue (37, 38), designed to interact with locking elements (22) arranged on the support leg (16, 17) and defining at least two separate locking positions on the support leg (16, 17) for locking the position of the casing (2) along the support leg (16, 17). An operating element (7) acting upon the locking plates (26, 33) is designed to carry the locking plates (26, 33) in a direction essentially parallel to the axis of rotation (20).

Description

IMPROVED HEAD RESTRAINT

FIELD OF THE INVENTION

The invention relates to a head restraint for use in motor vehicles and comprises a support for supporting the head restraint and fixing the head restraint to the backrest of a vehicle seat, the support comprising a carrier and at least one support leg coupled to the carrier, together with an adjusting arrangement for adjusting the position of the head restraint in relation to an occupant of the motor vehicle, and the carrier being enclosed by a casing which is rotatably connected to the support along an axis of rotation running essentially at right angles to the support leg.

DESCRIPTION OF THE PRIOR ART

In order to prevent neck injuries, for example in collisions, it has long been usual to provide cars and other motor vehicles with head restraints. In many countries there is a statutory requirement to provide such head restraints, for example in passenger cars. There are also statutory regulations governing the design and strength of head restraints.

In order that the head restraints will function optimally both from the point of view of comfort and from the safety standpoint, they should be adjustable so that they can be adjusted individually for each occupant of the vehicle. There is therefore a desire to be able to adjust both the height and the angle of the head restraint in relation to the occupant's head. It is not uncommon for the occupant to alter the adjustment of the head restraint whilst the vehicle is underway. In particular it is often desirable to be able to adjust the angling in relation to the head. Since the head restraint is then in a position in relation to the occupant in which it is no longer visible to the occupant, it is particularly advisable that the adjusting mechanism be sufficiently easy to understand and operate that the head restraint can be adjusted without the occupant needing to turn round.

For safety reasons it is moreover advantageous if the height and angle adjustment can be locked in the set position, so that the position of the head restraint cannot be accidentally changed.

It has hitherto been necessary to operate two different adjusting arrangements in order to alter both the height and angle of the head restraint. There is therefore a need for a head restraint having a simple and convenient adjusting mechanism, which can be operated whilst underway and without having to be able to see the mechanism. There is furthermore a need for a head restraint having an adjusting mechanism which will permit both height and angular adjustment of the head restraint.

SUMMARY OF THE INVENTION

The present invention has now produced a head restraint of the type described in the introductory part, which permits easy and flexible adjustment of the height and angling. The head restraint according to the invention is primarily distinguished by the fact that the adjusting arrangement comprises a first locking plate having a recess designed to interact with a locking plate, firmly connected to the axis of rotation and having locking elements located successively and essentially radially around the axis of rotation and defining at least two separate locking positions for locking the position of the casing around the axis of rotation, and a second locking plate comprising a locking tongue, designed to interact with locking elements arranged on the support leg and defining at least two separate locking positions on the support leg for locking the position of the casing along the support leg, and that an operating element acting upon the locking plates is designed to carry the locking plates in a direction essentially parallel to the axis of rotation. The head restraint is commonly fixed to a vehicle seat by two support legs. According to one embodiment of the invention the support therefore comprises two support legs, which each have locking elements, defining at least two separate locking positions of each support leg. The second locking plate accordingly has two locking tongues, which are each designed to interact with the locking elements on a support leg. The locking plate is designed to be moved sideways through the head restraint in an essentially horizontal direction. It is therefore advisable that the locking positions, which on each support leg are intended for adjusting the head restraint to a certain height, be arranged on the same level in relation to one another. Alternatively it is naturally feasible for the locking elements on the support legs to be arranged at different heights to one another and designed to interact with locking tongues, which are correspondingly arranged at different locking plate heights.

One simple and efficient way of producing defined locking positions is to arrange notches in the support leg or support legs. Such notches may be formed, for example, during casting of the support leg or support legs. Alternatively the notches can be milled out subsequently. Operating the adjusting arrangement moves the locking tongues on the second locking plate into and out of the notches, thereby locking and releasing the head restraint in relation to the support legs. Another type of locking position- defining elements are tenons, between which a locking tongue can be introduced.

According to one embodiment of the invention the operating element comprises a pushbutton control which is designed to act upon the locking plates and to displace the locking plates for operating the adjusting arrangement. The pushbutton control may function purely mechanically, in that depressing the pushbutton control directly shifts the locking plates between the operating positions. Alternatively the pushbutton control may be coupled to an electrically powered motor, which actuates the locking plates. The locking plates may be designed for interaction with the operating element in that the first locking plate has a first end plate and that the second locking plate has a second end plate, the end plates constituting force transmission surfaces between the operating element, for example a pushbutton control, and the locking plates.

Should the operating element consist of a pushbutton control, this may comprise a single pushbutton which is designed to act upon both the first locking plate and the second locking plate.

Alternatively the pushbutton control may comprise a first pushbutton, which is designed to act upon the first locking plate, and a second pushbutton, which is designed to act upon the second locking plate. The first pushbutton and the second pushbutton then advantageously have different physical designs and differ, for example, in their surface texture, height, area or design shape. Such an embodiment enables an occupant to distinguish the two control parts by touch. The adjustment of the head restraint can thereby be altered without the occupant needing to see the pushbutton control.

According to a preferred embodiment of the invention, the adjusting arrangement has a first operating position and a second operating position.

The operating positions can thereby be suitably arranged so that the first operating position only permits adjustment of the height of the head restraint and the second operating position only permits adjustment of the angling of the head restraint. The first operating position is then arrived at by moving the locking plate to an inner limit position, past which the locking plate cannot be displaced, and the second operating position is arrived at by moving the locking plate to a position between the inner limit position and the outer limit position. The outer limit position constitutes a neutral position in which both the height adjustment function and the angling function are locked. When the locking plate is in the second operating position it is only possible to adjust either the height or the angle of the head restraint. The adjusting arrangement may be designed in such a way that it is always possible to raise the head restraint, regardless of the position of the locking plates. It is essential, however, that the head restraint in the locked position should withstand downward and lateral thrusts without the position of the head restraint being altered. The head restraint should suitably be capable of withstanding a pressure of at least 500N without shifting position.

In order to ensure that the height and angling functions are locked when they are properly adjusted to the desired position, the adjusting arrangement suitably comprises means for returning the locking plates to a neutral position in which the angling of the head restraint cannot be adjusted and the head restraint cannot be lowered. In its simplest form such means may be a knob or the like, which is manually pulled out to the neutral position. However, the means of return is preferably a spring element, such as a leaf spring or a coil spring which continuously exerts a return force on the locking plate. With such an arrangement the locking plate will always return to the neutral position as soon as the adjustment of the head restraint is completed.

Similarly the head restraint according to the invention may comprise means for returning the casing to a non-angled neutral position. Such means may comprise a spring element, for example.

Both the carrier and the casing are advantageously formed from rigid plastic. This means that these parts can readily be injection moulded. It is also possible, however, to use other materials, preferably metal, for forming any or some of the said parts. Combinations of materials are naturally also possible.

Similarly the support leg or the support legs are suitably composed of metal, but combinations of metal and plastics are also possible. A common form of support leg is a U-shaped metal frame with locking notches on the legs. The head restraint support legs may obviously have any suitable cross-sectional shape, for example rectangular, oval or circular. The support leg or support legs may also have a stepped shape.

The casing is advantageously formed from rigid plastic and is arranged at least over a front section of the head restraint. However, the casing preferably fully encloses the internal parts of the adjusting mechanism. It is advisable to form the casing with a front part and a rear part. At least the front part of the casing is usually also covered by a cushion of shock- absorbent foam plastic, such as polyethylene foam. An outer cover, such as a covering of the same material as the rest of the vehicle upholstery, may be arranged on top of the foam plastic cushion.

DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail below with reference to the figures shown in the drawings attached, in which:

Fig. 1 shows a side view of a head restraint according to the invention,

Fig. 2 shows an opened head restraint according to the invention,

Fig. 3 shows the head restraint in Fig. 2 viewed in cross section,

Fig. 4 shows a locking plate for adjusting the angling of the head restraint shown in Figs 1 to 3,

Fig. 5 shows a locking plate for adjusting the height of the head restraint shown in Figs 1 to 3, Fig. 6 shows a detailed representation of the locking plates in Figs. 4 and 5,

Fig. 7 shows a locking plate in an adjusting arrangement according to the invention,

Fig. 8 shows the locking plate in Fig. 4 fitted to an axis of rotation and

Fig. 9 shows a divided pushbutton control for an adjusting arrangement according to the invention.

DETAILED DESCRIPTION OF AN EMBODIMENT

Fig. 1 shows a head restraint 1 without the shock-absorbent cushion that usually covers the outside of a head restraint. Such a cushion may be made, for example, from a dimensionally stable polyethylene foam or similar material.

Visible in Fig. 1 are a casing 2 comprising a front part 3, intended to be turned towards an occupant of a vehicle, and a rear part 4, intended to be turned away from the occupant. The casing 2 may be made, for example, of rigid plastic, or some other dimensionally stable impact-resistant material. In order to increase the stability in the casing 2, it may be designed, as shown in Fig. 2, with a stiffening internal framework. Such a framework in a plastic casing is suitably produced in conjunction with the forming of the actual casing. The casing 2 is shown in a side view in Fig. 1 and partially encloses a support 5, by way of which the head restraint can be fixed to a vehicle seat

(not shown), and an adjusting arrangement 6. The adjusting arrangement 6 can be operated by means of an operating element in the form of a pushbutton control 7. The head restraint 1 has a front side 8, a rear side 9, two lateral surfaces 10, 11 , an upper side 12 and an underside 13. The pushbutton control 7 is then arranged on one of the lateral surfaces 10. The pushbutton control 7 is usually arranged on the lateral surface 10 situated on the left-hand side of the occupant. In this way the pushbutton control 7 can be operated with the left hand, whilst the adjustment of the head restraint 1 , which requires greater control of movement, can be undertaken with the right hand.

In Fig. 2 the rear part 4 of the casing 2 has been removed so as to reveal the interior of the head restraint 1. It can be seen from this that the support 5 comprises a carrier 14, which is coupled to a frame 15 having two vertical support legs 16, 17. The support legs 16, 17 run in channels 18, 19 in the carrier 14 and thereby allow the carrier 14 and the casing 2 to be pulled upwards and downwards on the support legs 16, 17. The carrier may be formed from rigid plastic, metal or the like and the frame 15 is suitably a metal frame, of steel for example.

The casing 2 is pivotally connected to the carrier 12 by way of a horizontal axis 20, so that the casing 2 can be swivelled forwards and backwards, thereby adjusting the angle between the support legs 16, 17 and the casing 2.

The horizontal shaft 20 supports a fixing plate 23, which is firmly anchored in the casing 2 and to which a locking plate 24 is fitted. The locking plate is arranged essentially at right angles to the axis of rotation 20 and has a defined thickness. The locking plate 24 is furthermore toothed and in the example shown, for example, has four teeth 25, which define three locking positions between them. Alternatively, it is naturally possible to use a locking plate having just three teeth, or one having more than four teeth.

The locking plate 24 interacts with a first locking plate 26, which runs in a first groove 27 in the carrier 14. The locking plate 26 is operated by the pushbutton control 7 by way of a first end plate 28 and can be moved to and fro sideways through the groove 27 in the carrier 14. By depressing the pushbutton control 7 the locking plate 26 is therefore brought towards the lateral surface 10 of the casing 2 opposite the pushbutton control 7. When the pushbutton control 7 is no longer depressed, the locking plate 26 is returned to its original position by the action of a first coil spring 29 arranged between the carrier 12 and the locking plate 26. As an alternative, it is obviously possible to use some other type of return arrangement, such as a leaf spring, or quite simply to arrange the coupling between the pushbutton control 7 and the locking plate 26 in such a way that the locking plate 26 can be manually returned to the original position.

As Fig. 4 shows, the first locking plate 26 comprises an essentially rectangular rail, preferably of metal, lying vertically in the carrier 14. A recess 21 , which is intended to interact with the locking plate 24, is arranged on the locking plate 33. For this purpose the recess has a width corresponding to the thickness of the fixing plate 24, so that the fixing plate 24 can be moved to and fro through the recess when adjusting the angling of the head restraint. By moving the locking plate 26 in a horizontal direction, the recess 21 can be made to coincide with the location of the locking plate 24 on the axis of rotation 20. The rotational function of the head restraint is thereby released and it is possible to adjust the angle of the head restraint in relation to the support 5 by turning the head restraint about the axis of rotation 20.

The fixing plate of the axis of rotation 20 is connected to the carrier 14 by means of a coil spring 43. When the head restraint is angled outwards, the coil spring 43 endeavours to return the head restraint to the non-angled neutral position. This means that when the rotational function is released, the head restraint will automatically return to a non-angled position, unless a counter-force is applied to the head restraint in order to adjust the angling thereof.

In order to allow locking of the head restraint 1 in various height positions, the support legs 16, 17 are provided with locking notches 22, which define separate locking positions. In the exemplary embodiment shown the locking notches 22 are arranged on that side of each support leg 16, 17 facing the lateral surface 12 of the head restraint remote from the pushbutton control 7. Other locations are obviously feasible without departing from the scope of the invention.

The locking notches 22 on the support legs 16, 17 interact with a second locking plate 33, which runs in a second groove 34 in the carrier 14. Like the first locking plate 26, the second locking plate 33 is operated by the pushbutton control 7 by way of second end plate 35 and can be moved to and fro sideways through the groove 34 in the carrier 14. By depressing the pushbutton control 7 the locking plate 33 is therefore brought towards the lateral surface 10 of the casing 2 opposite the pushbutton control 7. When the pushbutton control 7 is no longer depressed, the locking plate 33 is returned to its original position by the action of a second coil spring 36 arranged between the carrier 12 and the locking plate 22. As an alternative, it is obviously possible to use some other type of return arrangement, such as a leaf spring, or quite simply to arrange the coupling between the pushbutton control 7 and the locking plate 33 in such a way that the locking plate 33 can be manually returned to the original position.

As Fig. 5 shows, the second locking plate 33 comprises an essentially rectangular rail, preferably of metal, lying horizontally in the carrier 14. Two outwardly angled locking tongues 37, 38, which are intended to interact with the locking notches 22 on the support legs 16, 17, are arranged on the locking plate 33. The outwardly angled locking tongues 37, 38 are L-shaped, the outer segment of each of the locking tongues 37, 38 being capable of engagement in and disengagement from the locking notches 22. When the locking tongues 37, 38 are inserted into the locking notches 22, the casing 2 cannot be lowered on the support legs 16, 17. The locking notches 22 are formed with an angled upper section 40 and a horizontal lower section 41. This is most easily seen from Fig. 2. Such a design of the locking notches 22 means that it is possible, against a certain resistance, to raise the head restraint on the support legs 16, 17, even though the locking tongues 37, 38 are inserted in the locking notches 22. On the other hand, the horizontal mower section 41 of each locking notch 22 constitutes an effective guard against downward adjustment of the head restraint when the locking tongues 37, 38 are inserted in the locking notches 22.

When the adjusting arrangement 6 is in neutral position, that is to say with the locking plates 26, 33 brought fully out towards the lateral surface 11 on which the pushbutton control 7 is arranged, it is not possible to adjust the angling or to lower the height of the head restraint 1. In the neutral position the recess 21 on the first locking plate 26 is disengaged from the locking plate 24 on the axis of rotation 20 and the outwardly angled locking tongues 37, 38 on the second locking plate 33 are inserted into locking notches 22 on the support legs 16, 17.

As can be seen from Fig. 2 and 6, the end plate 28 of the first locking plate 26 is situated outside the end plate 35 of the second locking plate 33. By depressing the pushbutton control 7, the first locking plate 26 is first brought sideways until its recess 21 on the locking plate 26 coincides with the locking plate 24 on the axis of rotation 20. This makes it possible to adjust the angling of the head restraint 1. In this position the second locking plate 33 has still not yet been brought out of its neutral position, the outwardly angled locking tongues 37, 38 on the second locking plate 33 still being inserted in the locking notches 22 on the support legs 16, 17. This means that the height adjustment function is locked, in so far as the design shape of the locking notches 22 prevents lowering of the head restraint 1. By further depressing the pushbutton control 7, the first locking plate 26 is carried further sideways until the first end plate 28 comes into contact with the second end plate 35 arranged on the second locking plate 33. Continued depression of the pushbutton control 7 now also causes the second locking plate 33 to move so that the outwardly angled locking tongues 37, 38 leave the locking notches 22 on the support legs 16, 17. In this position the head restraint 1 can be freely moved up and down on the support legs 16, 17, so that the height of the head restraint can be adjusted.

After having performed the desired height and angle adjustments, the adjusted position of the head restraint can be locked by releasing the pushbutton control 7. The locking plates 26, 33 are thereby automatically returned by the coil springs 29, 36 to the original neutral position, in which both the height adjustment function and the angling function are locked.

In the exemplary embodiment described here, therefore, the adjusting arrangement 6 has a first, outer adjustment position in which the angling of the head restraint is adjusted and a second inner adjustment position in which only the height can be adjusted. Such an arrangement is advantageous, since it means that the height can be adjusted by the occupant at the start of a journey and that the angling can then be repeatedly adjusted whilst underway, without affecting the height adjustment. As stated earlier, each occupant usually only wishes to adjust the height of the head restraint once, whereas for reasons of comfort it may be necessary to adjust the angling of the head restraint several times. However, the invention is not limited to the arrangement described but also encompasses variants in which the first adjustment position is a height adjustment position and the second adjustment position is an angling adjustment position.

In the example shown the sequence of the adjustment positions is determined by the location of the first and second end plates 28, 35 in relation to one another. Couplings between the locking plates other than the end plates shown are naturally feasible. For example, there may be a fixed connection between the locking plates, so that operation of the pushbutton control always acts on both of the locking plates simultaneously. Instead of designing the pushbutton control 7 as a single pushbutton, as described above, it is possible to use a divided pushbutton control, as shown in Fig. 9. The pushbutton control in Fig. 9 comprises a first pushbutton 7a, which is designed to act upon the first locking plate 26, and a second pushbutton 7b, which is designed to act upon the second locking plate 33. By using a divided pushbutton control 7, it is possible to control the height adjustment function and the angling function independently of one another. With a divided pushbutton control, however, it is also possible to achieve either simultaneous or individual adjustment of the different functions. Thus a first part 7a of the pushbutton control 7 may be designed to act upon two coupled locking plates, preferably of a design corresponding to that shown in Fig. 6, the first part of the pushbutton control 7a acting directly on the first end plate 28 and indirectly on the second end plate 35. A second part 7b of the pushbutton control, however, may be designed to act solely upon one of the locking plates 26, 33. In the example shown in Fig. 6 the second part 7b of the pushbutton control 7 then acts directly upon the second end plate 35.

In order to allow an occupant to distinguish the different parts of the pushbutton control 7, the first pushbutton and the second pushbutton appropriately have different physical forms and differ, for example, in their surface texture, height, area or design shape. In the example shown in Fig. 9 the second pushbutton 7b has a number of raised stipples which are easy to identify by touch.

The example shown describes a head restraint which can be swivelled about an axis 20 located in the lower part of the head restraint, that is to say having a pivot point situated low down. Naturally it is alternatively possible to apply the invention to head restraints having a high pivot point.

Claims

1. Head restraint (1) for use in motor vehicles and comprising a support (5) for supporting the head restraint and fixing the head restraint to the backrest of a vehicle seat, the support (5) comprising a carrier (14) and at least two support legs (16, 17) coupled to the carrier (14), together with an adjusting arrangement (6) for adjusting the position of the head restraint in relation to an occupant of the motor vehicle, and the carrier (14) being enclosed by a casing (2), which is rotatably connected to the support (5) along an axis of rotation (20) running essentially at right angles to the support leg (16, 17), c h a r a c t e r i z e d i n that the adjusting arrangement (6) comprises a first locking plate (26) having a recess (21) designed to interact with a locking plate (24), firmly connected to the axis of rotation (20) and having locking elements (25) located successively and essentially radially around the axis of rotation and defining at least two separate locking positions for locking the position of the casing (2) around the axis of rotation, and a second locking plate (33) comprising a locking tongue (37, 38) designed to interact with locking elements (22), arranged on at least one of the support legs (16, 17) and defining at least two separate locking positions on the support leg (16, 17) for locking the position of the casing (2) along the support leg (16, 17), and that an operating element (7) acting upon the locking plates (26, 33) is designed to carry the locking plates (26, 33) in a direction essentially parallel to the axis of rotation (20), and that the support legs (16, 17) have locking elements (22), defining at least two separate locking positions on each support leg (16, 17), and that the second locking plate (33) has two locking tongues (37, 38), which are each designed to interact with the locking elements (22) on a corresponding support leg (16, 17).

2. Head restraint according to claim 1 , c h a r a c t e r i z e d i n that the locking positions on the support leg or the support legs (16, 17) are defined by notches (22) in the support leg or the support legs (16, 17).

3. Head restraint according to claim 1 or2, characterized in that the operating element comprises a pushbutton control (7).

4. Head restraint according to claim 3, characterized in that the first locking plate (26) has a first end plate (28) and that the second locking plate (33) has a second end plate (35) and that the end plates (28, 35) comprise force transmission surfaces between the pushbutton control (7) and the locking plates (26, 33).

5. Head restraint according to claim 3 or 4, characterized in that the pushbutton control comprises a single pushbutton (7), which is designed to act upon both the first locking plate (26) and the second locking plate (33).

6. Head restraint according to claim 3 or 4, characterized i n that the pushbutton control (7) comprises a first pushbutton (7a), which is designed to act upon the first locking plate (26), and a second pushbutton (7b), which is designed to act upon the second locking plate (33).

7. Head restraint according to claim 6, characterized in that the first pushbutton (7a) and the second pushbutton (7b) have a different physical design and differ, for example, in their surface texture, height, area or design shape.

8. Head restraint according to any one of the preceding claims, characterized in that the adjusting arrangement (6) has a first operating position and a second operating position.

9. Head restraint according to claim 7, characterized in that the first operating position permits adjustment of the angling of the head restraint but prevents lowering of the head restraint and the second operating position only permits adjustment of the height of the head restraint.

10. Head restraint according to any one of the preceding claims, characterized in that the carrier (14) is formed from rigid plastic.

11. Head restraint according to any one of the preceding claims, characterized in that the support leg or the support legs (16, 17) is/are composed of metal.

12. Head restraint according to any one of the preceding claims, characterized in that the casing (2) is formed from rigid plastic and is arranged at least over a front section (3) of the head restraint.

13. Head restraint according to any one of the preceding claims, characterized in that the adjusting arrangement (6) comprises means for returning the locking plates (26, 33) to a neutral position in which the angling of the head restraint cannot be adjusted and the head restraint cannot be lowered.

14. Head restraint according to claim 13, characterized in that the means for returning the locking plates (26, 33) to the neutral position comprise a spring element (29, 36).

15. Head restraint according to claim 14, characterized in that the spring element is a leaf spring or a coil spring (29, 36).

16. Head restraint according to any one of the preceding claims, characterized in that the adjusting arrangement (6) comprises means (43) for returning the casing to a non-angled neutral position.

17. Head restraint according to claim 16, characterized in that the means for returning the casing (2) to a non-angled neutral position comprises a spring element (43) such as a coil spring.