A headrest for motor verhicle seats

0001The invention relates to a headrest for Motor vehicle seats according to the preamble of claim 1. Such by DE 39 00 495 A1 (See there FIG. 3) known head restraint is intended by an optionally additionally movable head contact face special Conditions in an eventual crash Done account.

0002The headrest according to DE 39 00 495 A1 allows, without requiring additional seat reclining means, Done in a crash of a shift headrest side head bearing surface to the front to back of the head of the vehicle occupant.

0003The headrest according to DE 39 00 495 A1 uses to a pivotable forward in the main body of the headrest or linearly displaceable forward Headrest part (s. Fig. 3), which supports, through the discharge of a prestressed spring accumulator, under the effect as an inflating air bag is moved forward.

0004Along with this, in the headrest according to the DE 39 00 495 A1 means used, which a personal individual approach of headrest side head bearing surface on the back of the head the vehicle occupant by a separate horizontal adjustment the head bearing surface, eg at start Drive, allow.

0005The headrest according to DE 39 00 495 A1, however, perceived as in need of improvement, especially as they associated with considerable technical effort is.

0006According to a CD-Rom "Autoliv's ANTIWIPLASH SEAT (AWS)^" Copyright 1998, Autoliv Hammarverken AB (SE) is the movement of a vehicle seat with headrest shown at the event of a crash. A special feature is noteworthy that due to the crash-induced loads the seatback moved about their bending line backwards. in this connection the headrest is taken, so that the headrest side head bearing surface from the back of the head of Vehicle occupants moved away, so that consequently a harmful additional acceleration of the head is formed.

0007According to the aforementioned CD-Rom that is the inherent spring movement of the seat back caused acceleration compensated in that the headrest including its held in the seat back Support bars to a seat back arranged in the Pivot axis counter to the spring movement of the seatback turned forward and thereby of the mind Vehicle occupant is applied.

0008The solution presented by the aforementioned CD-Rom is, especially as they start a special design Seatback presupposes as very expensive perceived.

0009Starting from the head support according to the DE 39 00 495 A1, the invention is based on the object, to provide a headrest compact design, which occurring in a crash happening adverse Spring characteristics of a seat back with structurally simpler means considered than previously.

0010In combination with the features of the preamble of claim 1 is this giving up in accordance with the Features of the characterizing part of claim 1.

0011made features of the inventive solution the fact that the the headrest side head bearing surface forming head installation part solely by the energy discharge a mechanical spring store after is moved forward to the head of the vehicle occupant. This means that the invention relates to the energy relief limited a mechanical energy storage and does not require such an additional airbags.

0012In this case, the forward movement of the head contact part be a linear movement in a preferred manner.

0013A linear movement is conveniently achieved by that two cylindrical, in particular circular cylindrical, tubular body telescoped into each other are arranged and in its central cavity a Spring-loaded, such as at least one parallel to the tube longitudinal axes extending in the axial direction braceable spring such as a compression coil spring od. like., record. The spring store or the spring relies on the mutually opposed and distance from each other arranged bottom or arranged telescopically supporting surfaces of the two Cylinder tubes from.

0014Preference is given to circular cylindrical cylinder tubes related. The latter take a single coaxial with them arranged helical compression spring, in particular a cylindrical Helical compression spring, on.

0015According to the invention means are also provided, which the mechanical spring-loaded in its cocked hold position and assigned to which locking means are, with the means of a related the crash happening effective sensor can be unlocked, so that the storage spring, while the can move headrest part towards the back.

0016A particularly advantageous locking means can consist of a spring-loaded, that this in its tensioned by means of a metal clamping wire Position is maintained. This tension wire is at a crash event of an electric current flow-through, so that the resulting heat flow the tension wire to melt and rupture brings what the energy of the mechanical spring accumulator connected, with a forward movement of the head bearing surface, can discharge.

0017In a further embodiment of the invention are either in the main body of the headrest or in their mobile Headrest part proppant provided which at least upon reaching the most extended Relative position of the head contact surface of the main body the headrest and the head part of the plant with the head bearing surface apart arresting distance.

0018A preferred embodiment of the invention is that the inside of the main body or the head contact part at least one in the clamping position of the spring accumulator the pivoted arm is provided, which upon reaching the extended end position of the head contact part by spring action in a stretched Supporting layer is added that of a rapprochement Head installation part prevents the main body. This particular for the case that the head of the vehicle occupant during the crash event against the headrest side Head bearing surface is moved back.

0019It is expedient to erfindungegemäße headrest the possibility of horizontal adjustment provided. It may be a leveling system, wherein the head part of the plant including the spring store each part or a Part of the spring travel either in the tensioning sense or is moved in the relaxation sense.

0020On the other hand, the invention also provides the Headrest part, together with the maximum with its stored energy charged spring, the one end to inside the head part of the plant and the other end on a supported to the main body abutment connected, together with the head part of the plant and the abutment (Which in turn involving a Horizontalverstellweges supported on the main body of the headrest) to be adjusted horizontally in both directions.

0021Moreover, the invention provides for the possibility before, the purpose of leveling the entire headrest with respect to their base (for example, two may be formed supporting rods) in the horizontal direction either to the back head of the vehicle occupant or horizontally to move away from the latter.

0022A horizontal adjustment of a headrest total , according to the DE 31 09 522 C2 or example formed in accordance with DE 33 35 497 describes C2 be.

0023An important feature of the invention is that the leveling system in a crash happening either automatically by itself or by other means can be arrested.

0024Another important feature of the invention that an optional height adjustment the headrest, is this headrests internally or seat back side exists in a crash Done is lockable automatically or by other means.

0025The aforementioned locking of the horizontal and / or vertical adjustment can, however, also before a possible crash happening already during be locked normal driving.

0026Another embodiment of the invention, instead the mechanical spring store a mechanical used energy storage device, the one in the central cavity of the two tubular bodies arranged piston-cylinder unit , whose cylinder interior least indirectly from a storage medium for moving the piston and / or the cylinder in the direction of extension of the is head installation part acted upon.

0027This formation of a mechanical invention Force or energy accumulator allows terms the weight and for the extension process of the Head installation part any required energy density a greater range of variation than those in use of energy storage systems with rigid springs, such as by Steel coil springs, could be achieved.

0028Thus, the invention provides, for example, in connection with a crash happening the cylinder interior at least indirectly from the gas stream to a gas source to act upon. The gas pressure may have built up, similar to a spring-relieved memory with rigid springs, are used as a backstop.

0029Furthermore, the invention provides the gas source Belonging to the piston-cylinder unit either directly or, if the specific features of an application example require to order from the piston-cylinder unit.

0030Moreover, the invention provides that the gas stream immediately in connection with a crash event the cylinder interior acts. If Special an individual case requires, it is also possible for the Gastronome the interposition of a hydraulic to let act on the cylinder interior connection.

0031In the gas source itself may be a acting prestressed gas storage; It is also possible, that the gas source in the form of chemically bound energy present.

0032Another embodiment according to the Invention provides that the mechanical axis of action the spring store or the mechanical energy store different from the linear motion direction is and the spring or the energy storage via mechanical motion coupling with the head part of the plant connected is.

0033In application of the abovementioned features of the invention can the spring or the mechanical energy storage practically within the two tubular bodies take any mounting position because the Operative connection between the spring accumulator and the mechanical Energy storage and for moving headrest part via a mechanical movement clutch.

0034Such mechanical motion coupling can at the same time be designed so that such a motion reduction or movement translation contains.

0035In the event so that the piston-cylinder unit one to the outward movement of the head contact part should have low maximum lift, a mechanical Motion coupling used, the same time a Translation of the drive movement of the spring or the energy store allowed.

0036A with respect to the position of the vehicle occupant optimal design is so erfindungsgemäB constructed that its effective in a crash Done Sensor on the seat back side at the level of the hip pivot point, namely the so-called H-point arranged, is.

0037In the drawings, preferred embodiments shown in more detail in accordance with the invention, it show<sl><li>FIG. 1 shows a vertical section through a headrest with charged (cocked) spring-loaded,</li><li>FIG. 2 is a horizontal section according to the Section line II-II in Fig. 1,</li><li>Fig. 3 based on the representation of FIG. 1, the headrest for relief or by extension of the spring accumulator, and </li><li>Fig. 4 based on the representation of FIG. 1 shows an embodiment of a headrest with a turbocharged Energy storage.</li></sl>

0038A headrest for motor vehicle seats 10 has a headrest main body 11 and a relative to the latter approximately along the upwardly inclined axis x forward z direction movable headrest part 12 on.

0039The headrest 10 has a base in the form of two support rods 13, which in unspecified lined manner in a seat back not shown are height adjustable and lockable. The two tubular support rods 13 are also by means of a tubular yoke 14 interconnected top, which with the main body-side support frame 15 of the composed of main body 11 and head support part 12 Headrest body K in particular rigidly connected is.

0040At the shoring 15 is a circular cylindrical hollow inner cylinder 16 with its inner cylinder base 18, for example, attached by riveting 17th

0041The circular cylindrical inner cylinder 16 is of a circular cylindrical hollow outer cylinder 19 telescoped overlapped, the outer cylinder base 20 to the bottom 21 of an approximately pot-shaped holding part 22 as recordable is attached by riveting 23rd The holding member 22 forms part of the head part of the plant 12th

0042Outside is the approximately pot-shaped holding part 22 of padding 24 surrounded by an upholstery fabric 25th

0043Inside the inner cylinder 16 and within the formed by the inner cylinder 16 and outer cylinder 19 central cavity H is a compressed almost to block, So potential spring energy storage-containing, Memory spring 41, a helical compression spring, was added, which ends on two support or spring plates 26, 27 is supported. the the Components 26, 27 and 41 having spring-loaded is designated S.

0044The support or spring plate 27 is supported on the inside by the inner cylinder bottom 18, while the support or spring plate 26 directly (Fig. 4) or by means of an intermediate part 28 (Fig. 1 and 2) inside supported on the outer cylinder-floor 20th

0045Between the two support or spring plates 26, 27 is a shown only in FIG. 1 of metal Tension wire 29 arranged, which the two Stützbzw. Spring plates 26, 27, the latter played arresting, interspersed in Isolierstoffbuchsen 30th In schematic As shown in Fig. 1 in that the tension wire 29 outside two electrical terminals L and M via which an electric circuit, in particular a DC circuit can be short-circuited.

0046The short-circuiting of the current circuit is carried out at Crash conditions in that a crash sensitive Sensor a switching signal to a control unit, e.g. to a relay passes. The control unit fed then into the two terminals L and M to -mentioned short-circuit current one, such that the tension wire 29 melts and breaks. This eliminates the axial holding force between the two supporting or Spring plates 26, 27. Thus, moving to the exculpatory Spring-loaded S shown in FIGS. 1-2 or the charged or activated energy storage E of FIG. 4 the circular cylindrical outer cylinder 19 and at the latter supported headrest part 12 in the extension z outwardly, so that the state is reached in accordance with FIG. 3 is, in which the extended headrest part 12 shown in phantom.

0047A seen in FIG. 1 pivot bracket 31 forms two bearing lugs 32 for receiving a Trunnion 33 for pivotal mounting one each Swing-arms 34th

0048Each arm 34 is spring restoring force according to the arrows F, for example, a Winding or leg spring loaded so that the respective Pivot 34 is anxious that with respect to the respective bearing eye 32 forming panel section 35 adopt a rectilinear stretched support layer, the by a not shown rotary stop between 34 and 35 is stabilized. Two pivot arms 34 are integrally connected to one another via a web 36th

0049In the context of FIGS. 1-4 is conceivable that in the extended position of the spring store S or the energy accumulator E (Fig. 3) extending in its stretched Support position located ends pivot arms 34 a the extending such opposite movement of effective head support member 12 back to the main body 11 prevent, as the example spherically shaped ends 37 of the pivot arms 34 respectively at the bottom 21 of the cup-shaped Holding part 22 support.

0050In addition it should be mentioned that one of reasons Simplified drawing in FIGS. 1 and 4, Swing arms 34 are not shown. Also as was the Overall arrangement of the surge tank S with the cylinders 16, 19 and the energy store E in Fig. 3 are not shown.

0051In Fig. 1 also indicates that the main body 11 and at the top part of the plant 12 and provided each other cooperating locking teeth 38, 39 while delaying the Headrest part 12 allow the main body 11, however, inadvertent removal of the head contact part 12 prevent the main body 11th

0052As mentioned above, the headrest 10 with a device for horizontal adjustment along the axis X or along a to the axis x be provided inclined direction. These would, for example according to DE 31 09 592 C2 or DE 33 35 497 describes C2 contract rod side (eg on the yoke 14) on the one hand and the headrest body K on the other hand relative to each other adjustable components (eg rack and pinion) can be arranged.

0053The headrest side head bearing surface is 40 designated.

0054According to FIG. 4 instead of the mechanical Spring accumulator S in FIG. 1 and 2 in the central Cavity H of the two tubular bodies 16, 19, a mechanical Energy storage E arranged that a Piston-cylinder unit 42 has. The piston-cylinder unit 42 has a hollow piston 43 whose circular disc-like piston part A in the cylinder interior 45 a cylinder 46 is arranged, from whose cylinder base B a more schematically illustrated plastic packaged propellant charge 47 in the cylinder interior 45 and into the cavity 48 of the hollow piston 43 protrudes.

0055The propellant charge 47 may have two electric cables 49, 50 ignited. This has the consequence that the hollow piston 43 through under the action of the propellant gas its clevis-like plunger 44 and on the support plate 26 the cylindrical outer cylinder 19 so So also the head contact portion 12, in the left Z direction shifted. The generated during this process LPG can also be used as a backstop, which prevents the head support part 12 without Another of its extended support position (Fig. 3) returned to the initial position shown in Fig. 4 can be.