Vehicle seat having an anti-submarining device and method

The invention relates to vehicle seat comprising a seat part and to a restraint device and a corresponding method of manufacture. The vehicle seat comprises an anti-submarining restraint device for preventing an occupant from slipping through on the vehicle seat when decelerated due to a crash, said restraint device being settable to an extended inactive position and said restraint device being settable to an extended active position. The seat part, in the longitudinal direction of the vehicle, has a padding defining a seat area, and a padding support below said padding. The restraint device is arranged between the padding support and the padding and spaced apart from the lateral parts by means of a locking element (e.g. detent recesses (28) or the like) provided for locking the restraint device in the active position.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a National Stage filing and claims priority to International Application No. PCT/EP2007/005581, filed Jun. 25, 2007, entitled “VEHICLE SEAT COMPRISING A SEAT PART AND AN ANTI-SUBMARINING RESTRAINT DEVICE, RESTRAINT DEVICE AND METHOD OF MANUFACTURE” which claims priority to German Patent Application No. DE 10 2006 029 331.2 filed Jun. 23. 2006, the entire disclosures of which are incorporated herein by reference.

The present invention relates to a vehicle seat with a seat section and with a restraint device for preventing submarining of a passenger on the vehicle seat during an accident-induced deceleration, wherein the restraint device can be set in a retracted inactive position, and wherein the restraint device can be set in an extended active position, wherein the seat section has a padding, which defines a seat surface, and a padding support which is provided beneath the padding.

Such vehicle seats are generally known. For example, a motor vehicle seat with a seat surface on the surface of a padding is known from German laid-open specification DE 102 31 794 A1, wherein a seat pan is provided beneath the seat surface, and wherein between the seat pan and the seat surface of the seat section a U-shaped adjusting element is arranged, which in the case of a crash can be moved out from an initial position in such a way that the seat surface and the adjusting element counteract a forward displacement in the longitudinal direction of the vehicle of the pelvis of a person sitting on the seat surface. With this vehicle seat, the actuating unit has means for returning the adjusting element to the initial position, wherein the actuating unit, after the return of the adjusting element to the initial position, ensures a renewed movement of the adjusting element in a new crash case. This has the disadvantage that the restraint device cannot be blocked in its active position. Furthermore, the known vehicle seat has the disadvantage that for realizing an active restraint device for preventing submarining of a person sitting on the vehicle seat (a so-called anti-submarining restraint device), i.e. a restraint device which can be transferred from an inactive to an active extended position, it is provided as a rule that the restraint device, during assembly of the vehicle seat, must be connected to structural elements of the vehicle seat, such as seat side sections or a seat section frame or the like, as a result of which there is no modularity in the sense of the possibility of deciding only at a late stage of the seat production or of the seat completion whether the vehicle seat is to be equipped with a restraint device or not. In the case of known vehicle seats, therefore, a larger number of variants of the vehicle seat have to be taken into consideration over a larger part of the production chain of the vehicle seat, which altogether leads to higher cost in the case of logistics and production. A vehicle seat with a seat frame, a seat cushion and a seat cushion support is known from German laid-open specification DE 199 43 595 A1, wherein in the longitudinal direction an anti-submarining ramp is attached approximately in the middle of the seat padding support, extends to the front edge of the seat padding support and covers approximately the front half of the seat padding support. A normally folded-up airbag, which is inflated in the event of a crash, is provided between the ramp and the seat padding support, or is embedded in the ramp. The airbag is provided in such a way that the gas which inflates the airbag can then escape again, for example by the bag fabric being permeable to air. Also in this case, the restraint device cannot be blocked in its activated position.

The present invention is therefore based on the object of providing a vehicle seat with a restraint device for preventing submarining of a passenger on the vehicle seat in the case of an accident-induced deceleration, wherein the vehicle seat for one thing can be equipped with such a restraint device easily and simply with the least possible cost and as late as possible in the production chain of the vehicle seat, and wherein for another thing the restraint device is equipped in such a way that a locking of the restraint device or a blocking of the restraint device in its active position is provided.

The object is achieved by means of a vehicle seat with a seat section and with a restraint device for preventing submarining of a passenger on the vehicle seat, wherein the restraint device can be set in a retracted inactive position, and wherein the restraint device can be set in an extended active position, wherein the seat section, in the longitudinal direction of the vehicle, has side sections on both sides, wherein the seat section has a padding which defines a seat surface, and a padding support which is provided beneath the padding, and wherein in addition the restraint device, with a locking means which is provided for locking the restraint device in the active position, is arranged between the padding support and the padding and also at a distance from the side sections. As a result of this, it is advantageously possible that for one thing the modularity of the restraint device is ensured, i.e. the possibility of deciding only at a late point in time in the production chain of the vehicle seat whether a specific vehicle seat is to be equipped with a restraint device according to the invention or not. For another thing, this is possible by the correct functionality of the restraint device being able to be ensured in an especially easy and safe manner since after a single extension of the restraint device into its active or extended position a blocking takes place in such a way that the restraint device can no longer be moved, or at least no longer completely moved, into its inactive or retracted position (or this being possible only with disproportionately large forces). According to the invention, it is especially preferred if the restraint device has an actuating means, especially a pyrotechnic linear actuator and/or a reversibly operating actuator, wherein the actuating means is arranged between the padding support and the padding, or is supported between the padding support and the padding, wherein in particular an operation of the actuating means is already provided in terms of time before the existence of an accident-induced deceleration. In the case of supporting the actuating means between, the padding support and the padding, the actuating means can partially also extend or be arranged beneath the padding support. Linear actuators are comparatively small and can be realized in a compact manner in terms of installation space, so that as a result of this the restraint device can be configured in an especially compact manner in terms of installation space and according to the invention the modularized installation method of the restraint device in the vehicle seat can be especially easily realized. In the sense of the present invention, a padding support is understood to be a single structural component or a multiplicity of structural components of the seat section, which are provided at least in the proximity of the padding which is possibly to be fastened later on the seat, and which retain or support the padding. For example a padding support which continues essentially over the entire seat surface, as an essentially universal cushion pan or seat pan is a possibility as a padding support in this case. Furthermore, according to the invention, for example a so-called split seat pan or divided seat pan is a possibility, in which such a split seat pan supports approximately the front half or only the front or rear approximately 20% or just 10% of the padding. Furthermore, structural elements such as tubular or open stiffening elements are also a possibility as part of the padding support. In the case of a padding support in the sense of the present invention this can also partially have an underspringing. According to the invention, for example a pyrotechnic linear actuator, also a reversibly operating actuating means, for example an electric motor-powered linear actuator, can be provided alternatively or cumulatively to an irreversibly operating actuating means and together with corresponding sensors (pre-crash sensors) which anticipate an accident, leads to a setting of the extended active position of the restraint device or to a setting of an intermediate position of the restraint device (between the inactive position and the active extended position) already before an accident occurrence in terms of time and therefore before the existence in terms of time of an accident-induced deceleration (i.e. a deceleration which is typical for an accident occurrence).

Furthermore, it is preferred if the restraint device has a positioning element which is movable by the actuating means, wherein the positioning element is adjustable by means of the actuating means from a retracted position which corresponds to the inactive position of the restraint device into an extended position which corresponds to the active position of the restraint device. As a result of this, it is possible that the positioning element can be optimized to the respective application case independently of the actuating means, for example with regard its compressibility (for example for energy dissipation during an accident situation), or also with regard to its dimensions which in their turn for example have an influence on the extension degree of the restraint device.

Furthermore, it is preferred that a rotation around an axis which extends essentially horizontally and especially transversely to the direction of the vehicle is provided between the retracted position and the extended position of the positioning element, wherein the positioning element is preferably provided as a plate-form positioning element, and wherein the rotation around the essentially horizontally extending axis is preferably provided as a rotation in the direction of travel. As a result of this, a plate can be used as the positioning element which extends essentially over the entire width of the restraint device which can preferably be installed in a modular manner, wherein the plate in the retracted position of the positioning element is arranged essentially parallel to the seat surface or parallel to the padding support, and in the extended position of the positioning element is arranged essentially perpendicularly to the seat surface or perpendicularly to the padding support. Between the positioning element and the padding of the seat section, according to the invention there is preferably a cover of the restraint device in the sense of an anti-submarining ramp. As a result of this, it is advantageously ensured that the body of the seat's occupant in the case of an accident situation (i.e. a negative acceleration or a deceleration, which exceeds a prespecified limiting value) exerts a force action upon the restraint device over the largest possible area so that the risk of injury of the seat's occupant is lessened. A particular advantage of a movement of the positioning element in the direction of the vehicle is that the force action of the actuating means, especially a pyrotechnic linear actuator, can be selected in such a way that the force action of the actuating means or its extension in any case is not directed in the direction of main body parts (especially in the direction of the pelvis or in the direction of the trunk) of the seat's occupant. As a result of this, the risk of injury is likewise reduced.

According to the invention, it is additionally preferred that a rotation at least of a part of the positioning element around an axis, which extends essentially vertically, is provided between the retracted position and the extended position of the positioning element, wherein the positioning element is preferably provided as a telescopically extendable positioning element with one or more extendable elements. As a result of this, it is advantageously possible that the positioning element can be realized in a compact type of construction, for example by means of cup-like components which telescopically inter-engage, and for realizing the extended position from the retracted position a rotational movement of at least one of the cup-like components around its center is carried out. In this case, a spirally designed pin-and-slot guide of the at least two cup-like components is preferably provided according to the invention for converting the rotational movement into an extending movement. For realizing a locking of such a positioning means, the pin-and-slot guide can be configured by means of for example an asymmetrical toothing in such a way that only a movement in the direction of the extending movement is possible. Alternatively to an exemplary pin-and-slot guide, in the case of the telescopically extendable variant of the positioning element it can also be provided according to the invention that for example two cup-like components inter-engage like a thread and by means of a rotation of one of these components relative to the other a positioning is brought about.

Furthermore, it is preferred if the restraint device has a lower section and an upper section, wherein the lower section has fastening elements for connecting the restraint device to the padding support, or if the padding support has fastening elements for connecting the restraint device to the padding support. As a result of this, it is possible in a simple manner to create the connection between the restraint device and the padding support without expensive tools being required for it or without the task making high qualification demands. In this case, according to the invention a fastening by pushing on, or sliding on, or clipping, or adhesive fastening have proved to be especially preferable. Combinations of two or more such fastening possibilities can also be used, for example for securing a push-on connection or a slide-on connection. Alternatively to the embodiment variant of the restraint device with a lower section and an upper section, it can also be provided according to the invention that the functionality of the lower section (for example the provision of connecting points of levers or the like) is undertaken by the padding support (full integration of the lower section into the padding support) and that consequently the lower section can be saved so that the weight can be reduced and costs can be saved. For example, it is provided in this case that the restraint device, that is to say for example lever connections or the like of the restraint device, are screwed and/or riveted and/or pinned to the lower section.

Furthermore, it is preferred if the locking means has a drag lever or a telescopic lever, wherein the drag lever or telescopic lever is provided in a movable manner by means of the movement of the positioning element, or if the drag lever can be latched by means of latching bolts and/or by means of latching recesses, wherein by means of at least one spring element a blocking action of a displacement of the drag lever in the direction of the position which corresponds to the extended position of the positioning element to the position which corresponds to the retracted position of the positioning element is preferably provided. As a result of this, it is advantageously possible according to the invention that a modular type of construction of the locking means can be provided in such a way that the blocking force of the locking means can be set largely independently of the other characteristics of the restraint device. For example, it is possible according to the invention that the drag lever on its end opposite the positioning element is guided in a housing which accommodates a multiplicity of spring-loaded latching bolts which in the retracted position of the positioning element press upon the drag lever. As soon as the drag lever has extended far enough in the direction of the extended position of the positioning element, one of the latching bolts locks the return movement of the drag lever. By a multiplicity of such latching bolts a multiplicity of engaged positions can be defined. This is especially advantageous in case (on account of malfunction of the actuating means or on account of the particular situation of a seat occupancy for example by an abnormally large or an abnormally small person as the seat occupant) a movement of the positioning element into its furthermost extended position is not carried out.

Furthermore, it is preferred if the locking means has a slot and a bolt, wherein the bolt has an axial first section with reduced diameter, and an axial second section with enlarged diameter, and wherein an axial movement of the bolt is provided for bringing about the locking. A further embodiment variant of the restraint device for alternative realization of a locking means, according to the invention can provide a slot with a starting section and with an end section, wherein a bolt, which is moved together with the positioning element, engages in the slot, wherein the bolt in the inactive position of the restraint device is located in the starting section of the slot, and in the active position of the restraint device is located in the end section of the slot, and wherein the shape of the slot is configured in such a way that at least in the (fully) activated position, or active position, of the restraint device a reverse movement of the positioning element or of the bolt is prevented. In this case, the slot, according to a further variant of the locking means, can have for example a curvature or a bend point in such a way that the bolt which is moved with the positioning element can no longer be moved back into the starting section, or such a reverse movement is highly improbable, on account of the force ratios which exist in an accident situation. Furthermore, in a further variant an operating cam, also with a starting section and an end section for a bolt, can be provided instead of the slot, wherein the operating cam has a recess in the end section in such a way that the bolt which is moved with the positioning element likewise can no longer be moved back into the starting section, or such a reverse movement is highly improbable, on account of the force ratios which exist in an accident situation. In this case, it can preferably be provided that the element or component which features the operating cam is spring-preloaded in the direction of the inactive position. In the case of the embodiment variants with a slot, it can be advantageously provided in the same way that the element or component which features the slot is spring-preloaded in the direction of the inactive position. Furthermore, in a further variant, a slot, in a way in which it is configured in the style of a keyhole, can be formed with a starting section which has a reduced clear opening, and an end section which has an enlarged clear opening, in such a way, and interacting with a bolt, that the bolt has a smaller diameter in a first axial section and interacts with the starting section, and that the bolt, upon reaching the end section of the slot (which is to be carried out during a movement of the positioning element in the direction of the active position), with a second axial section of the bolt, which has a larger diameter, is pressed into the end section on account of a spring-pretensioning of the bolt. In a further embodiment variant of the restraint device, for alternative realization of a locking means, according to the invention the positioning element can interact with the upper section, especially with holes or recesses, in such a way that upon reaching the active position a reverse movement of the positioning element is prevented. According to the invention, it is furthermore provided that partial aspects of the different variants of the restraint device with a locking means can be combined with each other. In this way, for example the last-mentioned variant (holes or recesses in the positioning element) can be combined with the other variants.

It is especially preferred if a latching of the rotational setting of the positioning element between the extended position and the retracted position is provided by means of an asymmetrical toothing or by means of a wedge element. As a result of this, according to the invention it is possible with comparatively simple means to ensure a latching or locking of the restraint device in its active or activated position, or in one of its active positions. For example, it is possible that during a rotation of the positioning element around an essentially horizontal axis a ratchet-like locking of the positioning element is carried out in such a way that a reverse movement (into the retracted position of the positioning element) is no longer possible. Alternatively to this, it is also possible that a (for example spring-loaded) wedge element blocks a reverse rotation of the positioning element if there is a sufficiently large extending movement of the positioning element.

Furthermore, according to the invention it is preferred that a latching of the rotational setting of the positioning element between the extended position and the retracted position is provided by means of a bell-crank lever and a spindle. As a result of this, an especially secure and reliable locking of the positioning element in its extended position, or in one of its extended positions can be carried out, wherein it is especially advantageous in this case that a locking is virtually continuously possible, i.e. with virtually continuous blocking positions, so that an extended position which is once occupied by the positioning element is essentially fully maintained. As a result of this, the safety level of the restraint device according to the invention and the safety level of the seat according to the invention are advantageously increased.

Further subjects of the present invention relate to a restraint device according to the invention for a vehicle seat, and also to a method for producing a vehicle seat according to the invention, wherein in a first step the supporting structure of the vehicle seat is produced, and wherein in a second step the restraint device is connected to the padding support. As a result of this, it is especially possible that the complete production steps for producing the structural elements of the vehicle seat, for example the frame of the seat, the frame of a back section, the sub-construction of the seat section and the like, are carried out in the first production step and for example are undertaken in the factory of the seat section manufacturer. The integration of the restraint device into the vehicle seat, or with the seat section of those vehicle seats which are to be equipped with the restraint device, can then be undertaken in a production plant in the proximity of the final production of the vehicle seat or of the vehicle in which the vehicle seat is to be installed, wherein for this installation of the restraint device in the vehicle seat according to the invention there are significantly lower equipping requirements and furthermore significantly less qualification requirements of the employees who carry out the installation than for the production of the structural elements of the vehicle seat for which for example the production of welded joints is necessary.

InFIG. 1(in the left-hand part of the figure), a side view of a vehicle seat10according to the invention is schematically shown. The vehicle seat10comprises a seat section30and also as a rule a back section which is not provided with a designation. According to the invention, the seat section30especially has a frame-like structure with at least two seat side sections31on the sides. Inside this frame-like structure the seat section30has a seat pan34or a padding support34. A padding33or a seat cushion33is connected to the seat pan34or to the padding support34. The seat section30is connected to the floor sub-assembly16of the vehicle interior or to the body structure16of the vehicle by means of a seat substructure15. By means of the seat substructure15it can be provided according to the invention that the complete vehicle seat10is connected in a longitudinally adjustable and/or vertically adjustable and/or inclinably adjustable manner. For this purpose, in the left-hand part ofFIG. 1the seat substructure15is shown as outlined links which by rotating or pivoting can bring about a corresponding seat setting. The padding33has a seat surface32upon which a user of the vehicle seat10, or an occupant of the vehicle, or a passenger can be seated. According to the invention, it is provided in an especially preferred manner that the seat pan34or the padding support34together with the padding33and the seat surface32is provided in a vertically and/or inclinably adjustable manner in relation to the rest of the seat section30.

The seat section30of the vehicle seat10according to the invention for example can be provided as a two-times, or four-times, or six-times, or eight-times, or multiply adjustable substructure, as a result of which for example the seat height and/or the seat inclination and/or the seat longitudinal adjustment and/or the seat length setting (thigh support length) can be set. The padding support is shown in the figures largely as a separate and one-piece seat pan34or as a corresponding padding support34, but can also be provided as a split padding support34or a corresponding seat pan34, as can be seen with reference to the examples of embodiment variants of a padding support34which are shown inFIGS. 1aand1b. A single structural component or a multiplicity of structural components of the seat section are especially understood as a padding support, which are at least adjacent to a padding of the seat or are provided in the proximity of such a padding, for example approximately at a maximum distance of about 10 mm from such a padding, and wherein such a padding is carried, or supported or retained, by the padding support or by its components. As a padding support, in this case for example a continuous padding support (cushion pan or seat pan) (FIG. 1), or a split seat pan, or split seat bucket (FIG. 1a), are a possibility, or even structural elements such as tubular or open stiffening elements (FIG. 1b) as part of the padding support.

According to the invention, a restraint device20is arranged between the padding support34and the seat surface32, by means of which a submarining of the user of the vehicle seat10in the case of an accident-induced deceleration can be avoided or reduced. The restraint device20is provided as an active anti-submarining device and according to the invention is especially preferably designed as a so-called add-on element which can be selectively integrated into the vehicle seat10or not (depending upon equipping wishes of the customer or the specifications of the manufacturer). Such an active anti-submarining device component can offer an essential contribution to the improvement of occupant protection in the case of a head-on crash. The unit can preferably be installed as an add-on element in almost all front seats and also rear seats. In this case, the restraint device20can be especially preferably integrated into the vehicle seat10in a so-called JIT workshop (just-in-time workshop), i.e. in comparatively close proximity to the final assembly of the vehicle or of the complete seat module, by only a fastening of the restraint device20on the padding support34being carried out, for example via a known fastening technique such as clipping, screwing, riveting, adhesive fastening or the like. In this case, it is especially advantageous that preferably no welding operations whatsoever arise and also no modifications to structural components of the seat section30at all are necessary. Furthermore, according to the invention it is especially advantageous that an identical seat pan34or an identical padding support34can be used both for a vehicle seat10with the restraint device20and for a vehicle seat10without the restraint device20. As a result of this, the production costs for such vehicle seats10can be significantly reduced or the logistical additional expense for a flexible use of the restraint device20on any such vehicle seats is greatly reduced.

In the right-hand part ofFIG. 1, a perspective view of a seat pan34or of a padding support34of a seat section30of a vehicle seat10according to the invention is schematically shown, with a partially sectioned view of a restraint device20according to the invention.

FIG. 2schematically shows a perspective view of a seat pan34or of a padding support34of a seat section30together with the seat side sections31of the seat section30of the vehicle seat10according to the invention, with a view of the restraint device20according to the invention. Also, a part of the seat substructure15, which in this case is designed as an adjusting linkage for height adjustment and/or inclination adjustment of the vehicle seat10and is connected to the seat side sections31, is apparent fromFIG. 2.

FIGS. 3 and 4show schematically and sectioned in perspective view the seat pan34of the vehicle seat10according to the invention with an embodiment of the restraint device20in its inactive position21(FIG. 3) or in its active position22(FIG. 4). It is apparent that in the embodiment of the restraint device20which is shown this has a housing consisting of an upper shell46and a lower shell45. The housing of the restraint device20for example can comprise a steel material, an aluminum material, a magnesium material, a plastic material, or a combination of such materials. It is also apparent that in the active position22(FIG. 4) the upper shell46, by means of an actuating means23, is extended upwards, i.e. towards the seat surface32(which, however, is not shown inFIG. 4). As a result of this, the pelvic bone (or the ischium hump), which is not shown, of a seat user experiences a greater resistance particularly at an earlier point in time in the case of a head-on collision so that a submarining of the pelvis or of the hips of the user (forward displacement (displacement in the X-direction) of the so-called H-point or hip-point) can be avoided or its likelihood or extent significantly reduced. As a result of this, knee airbags which are preferably arranged in the dashboard and/or measures for belt tightening can advantageously be dispensed with or reduced. According to the invention, this can be especially advantageous particularly for 3-door vehicles.

For the positioning of the upper shell46of the restraint device20this comprises a positioning element24, which inFIGS. 3 and 4is shown only as a lever, which is driven by the actuating means23. In this embodiment of the restraint device20the positioning element24, during the movement between the inactive position21of the restraint device20and the active position22of the restraint device20, is rotated or pivoted around an essentially horizontal rotational axis (extending parallel to the seat surface32). As a result of this, the positioning element24is adjusted from a retracted position21′ which corresponds to the inactive position21of the restraint device20into an extended position22′ which corresponds to the active position22of the restraint device20so that the upper shell46is extended and, as a result of this, according to the invention a relatively large impact surface for the pelvic region of a user in an accident situation is provided. An alternative embodiment of the positioning element24is an essentially plate-form configuration of the positioning element24. A positioning element24which extends in an essentially flat manner corresponds to an essentially plate-form configuration of the positioning element24, wherein such an element for example is at least twice as long (as a rule oriented approximately in the Y-direction) as it is wide (as a rule oriented approximately in the X-direction in its inactive position), and has a depth of at most a third of its width. Alternatively to such an essentially plate-form element as a positioning element, it can also be provided according to the invention that a tube with a plate welded on or another structural element of the restraint device20serves as a positioning element24.

The positioning element24, according to the invention in the exemplary embodiment according toFIGS. 3 and 4, is rotatably or pivotably connected to the lower shell45or connected directly to the padding support34. This last-mentioned alternative connection of the positioning element24is especially advantageous when the lower shell45is not present. The connection of the positioning element24to the lower shell45and/or to the padding support34can especially be provided by means of one, or by means of two, or by means of three bearing points, or even by means of more than three bearing points. Two bearing points are advantageously provided on the lateral ends of the positioning element24(in the Y-direction).

Alternatively to a positioning element24which is rotatable around an essentially horizontal rotational axis, it is also possible according to the invention, and schematically shown inFIG. 19based on a third embodiment, that the positioning element24is rotatable around an essentially vertical rotational axis (essentially perpendicularly vertical on the seat surface32), or is rotatable at least in parts. In this case, the positioning element24for example has two reciprocating pistons which are especially cup-like in design and have a spiral pin-and-slot guide and also are rotatable relative to one another and during a rotation execute an axial extending movement along for example the common center axis. Alternatively to a rotation around a common center axis an eccentric rotation of the one reciprocating piston relative to the reciprocating piston or relative to another reciprocating piston can be also be provided. As a result of this, the installation space which is required for the restraint device20and also the weight can be reduced. Locking of the positioning element24in the extended position can be realized via a preferably asymmetrical toothing (as locking means25) between the two parts which are rotatably arranged in relation to each other. Furthermore, alternatively or cumulatively to the locking of the positioning element in the extended position, an energy dissipation behavior of a positioning element24which is provided in this way can be brought about relatively simply by arranging in the central region of the reciprocating pistons which are designed like cups either a shock absorber element, or a gas-pressure damper, or a deformation material such as a metal foam, a honeycomb structure, or a similar material which dissipates energy in the case of a deformation. In the case of the third embodiment of the positioning element24, two or more reciprocating piston units can also be provided.

Alternative embodiment variants of the restraint device20are shown inFIGS. 4a,4band4c, and also inFIGS. 23a,23b,23c,23d,23e,23f,23g,23h,23i,23j,23kand23l, in side view or in perspective view as the case may be.

InFIG. 4a, a variant of the restraint device20with a variable connection of the upper section46is shown in side view. The variable connection of the upper section46of the restraint device20is realized in the region facing away from the positioning element24by means of a lever101which in the initial position (inactive position of the restraint device20) is adjusted or pivoted towards the positioning element24. During an activation of the restraint device20, both the lever101and the positioning element24are rotated in the opposite rotational direction, wherein the upper section46is raised or positioned both in the region of the positioning element24(front) and in the region of the padding support34which faces away from the positioning element24, as a result of which a particularly good restraining action is achieved. When activating the restraint device20, a pin102of the positioning element is also moved in the X-direction inside an elongated hole103. Such an elongated hole103can be designed with latching recesses which together with the pin102form an example for a locking means25. In one variant of the restraint device20, which is not shown, the upper section46, as inFIG. 4a, is variably connected by means of the lever101, but the lever in the inactive position is adjusted in a manner in which it is rotated in the direction away from the positioning element24, and in the region of the positioning element24there is no elongated hole103but a simply pivotable bearing of the upper section46so that the lever101, the upper section46and the positioning element24form a four-bar linkage. As a result of this, an optimization of the installation space can be effected. The four-bar linkage kinematics (or corresponding kinematics with variable connection of the upper section46corresponding toFIG. 4a), compared with the embodiment which is shown inFIGS. 3 and 4, has the advantage that the upper shell46of the housing of the restraint device20is also raised in the rear region. This can contribute to an improved restraining functionality. Such four-bar linkage kinematics (or corresponding kinematics with variable connection of the upper section46corresponding toFIG. 4a) according to the invention can be arranged both parallel to the direction of travel and transversely to it, or even diagonally to it.

InFIGS. 4b(inactive position) and4c(active position), a further variant of the restraint device20, with the upper section46, which in the case of this variant is linearly movable essentially in only outlined linear guides and which during its linear or at least essentially linear movement positions the positioning element24, is shown in perspective view. In this case, the upper section46is driven by the actuating means23, which for example is provided as a helical spring, or another form of actuating means23is provided, for example a pyrotechnically operating linear actuator.

The upper shell46which is set in the active position22of the restraint device20(i.e. extended) can be configured in such a way that the forces on the pelvis of the occupant, which occur during the head-on crash and arise as a result of the impacting of the occupant upon the seat pan34, or seat shell34, or padding support34, or as a result of the impacting of the occupant upon the upper shell46are noticeably reduced by directed energy absorption of for example the upper shell46itself. Furthermore, the positioning element24in its structure can also be provided in such a way (for example by plates, foams of any type, honeycomb constructions or the like) that the forces which occur, especially the pelvic forces, are reduced.

The actuating means23can preferably be designed according to the invention as a pyrotechnic unit, or as a pyrotechnic actuator, preferably a linear actuator. According to the invention, however, it is alternatively or cumulatively also possible that the actuating means23is designed as a spring-preloaded element (with mechanically stored actuating energy), or is designed as an electromagnetic unit. In this case, it is especially advantageously provided according to the invention that the effective direction of the actuating means23, despite the relatively close arrangement of the actuating means23in relation to the user of the vehicle seat10, at no time is directed towards the user, or to sensitive body parts of the user (such as the torso or the pelvic region). As a result of this, the risk of injury, for example in the case of a material defect, can be significantly reduced. The effective direction of the actuating means23can be provided according to the invention either essentially parallel to the direction of the vehicle or else be established transversely to it, or even be established diagonally to it.

According to the invention, it is now provided for ensuring a good protection function of the restraint device20that during an actuation of the actuating means23the system is immediately locked against a movement back into the inactive position21. As a result of this, a maximum possible protection action in all conceivable situations is achieved even when the actual fully extended end position of the restraint device20is not reached. This locking of the restraint device20is ensured by means of a locking means25.

FIGS. 5,6and7schematically show in perspective view in each case a detail of the restraint device according to the invention with a first embodiment of the locking means25. The positioning element24(in the first embodiment of the locking means25as a plate-form positioning element24) is arranged in the region of the lower shell45of the restraint device20. The locking means25is fastened on the upper end of the positioning element24. According to the first embodiment, this has a drag lever26, on the side of which faces away from the positioning element24a plurality of latching bolts27or locking bolts27, which are spring-loaded by means at least one or more spring elements29, are provided. These latching bolts27prevent a reverse movement of the drag lever26after a movement of the drag lever26from the initial position of the drag lever26which is shown inFIG. 5(this corresponds to the retracted position21′ of the positioning element24or to the inactive position21of the restraint device20) into the extended position of the drag lever26which is shown inFIGS. 6 and 7.

According to variants of the first embodiment of the locking means25, which inFIGS. 8 to 17are schematically shown in perspective view, or in side view, or in exploded view, it can be providedthat the drag lever26has latching recesses28which interact with correspondingly formed latching bolts27(first variant,FIG. 8),that the drag lever26, or the end of the drag lever26which faces away from the positioning element24, interacts with latching recesses28in the region of the lower shell45, or in the region of the padding support34, for realizing a locking25of a reverse movement of the drag lever26(second variant,FIGS. 9,10and11),that the drag lever26, or the end of the drag lever26which faces away from the positioning element24, is provided with latching recesses28and interacts with further latching recesses28in the region of the lower shell45, or in the region of the padding support34(either as an additional element, for example a latching rail, or as a forming which is functionally integrated in the lower shell45or in the padding support34) for realizing a locking25of a reverse movement of the drag lever26, wherein a locking of the end of the drag lever26during the forward movement (in the direction of the extended position22′ of the positioning element24) is prevented by means of for example a film28′ as a locking protection (FIG. 12), wherein during a reverse movement of the drag lever26such a film is then punctured (FIG. 13) and the drag lever26locked (third variant,FIGS. 12 and 13), wherein the person skilled in the art knows that such a drag lever26as a rule has to be laterally guided (such a lateral guiding, however, is not shown),that the drag lever26, or the end of the drag lever26which faces away from the positioning element24, is provided with preferably asymmetrically formed latching recesses28, and in these latching recesses28a spring element29, which for example is arranged on a guide sleeve (engaging and therefore latching or locking after the style of the locking of a headrest rod), is provided (fourth variant,FIG. 14), andthat the drag lever26or the end of the drag lever26which faces away from the connecting point of the drag lever26to the positioning element24interacts with latching recesses28in the region of the upper shell46for realizing a locking25of a reverse movement of the drag lever26(fifth variant,FIGS. 15,16and17).

FIGS. 18 to 22schematically show in side view, or in perspective view, a second, third, fourth, fifth or sixth embodiment of the locking means25. In the case of the second embodiment which is shown inFIG. 18, the locking means25has a telescopic lever26′ alternatively or cumulatively to a drag lever26. In this case, such a telescopic lever26′ has a conical design of a guide cylinder26′″ so that in the end position of the telescopic lever26′ a locking is created as a result of the wedging of a rod26″ with the guide cylinder26′″.

A third embodiment of the locking means25, which is schematically shown inFIG. 19, has an asymmetrical toothing41between two telescopically inter-engaging cylinder elements which together form the positioning element24. In this case, the asymmetrical toothing41is designed in such a way that an extending movement of the cylinder elements is possible, but no reverse movement. According to a variant of this third embodiment of the locking means25, which is not shown, it is provided that a pin slot guide, or pin guide track, which is spirally arranged in the region of the circumference of the cylinder elements, in its end section which corresponds to the active position (extended cylinder elements) has a reduced pitch which in the event of a release of the restraint device20leads to the prevention of the movement into the inactive position of the restraint device.

InFIG. 20, a fourth embodiment of the locking device25is schematically shown, in which an asymmetrical toothing41together with a ratchet-like pawl41′ prevents a reverse movement of the positioning element24.

InFIG. 21, a fifth embodiment of the locking means is schematically shown, in which a wedge element42, especially a wedge element42which is spring-loaded by means of a spring element, is provided for blocking the positioning element in its extended position22′.

InFIG. 22, a sixth embodiment of the locking means25is schematically shown, in which a bell-crank lever mechanism43, or a bell-crank lever43provided with a spindle44, which is connected to the positioning element24, is provided. According to the invention, in the case of this embodiment it is provided that the spindle44allows a movement in the direction of a compression of the bell-crank lever (i.e. a movement to the position of the positioning element24according to the arrow44′), while a movement in the opposite direction is blocked, or there is a self-locking.

InFIGS. 23a,23b,23c,23d,23eand23f, two further variants of the restraint device20in the active position (FIGS. 23b,23c,23eand23f), or in the inactive position (FIGS. 23aand23d), are shown in perspective view. In this case, a slot80is arranged in a locking lever84which is arranged at the side. The slot80has a starting section81and an end section82. A bolt85, which is movable with the positioning element24, engages in the slot80and during a movement into the active position of the restraint device20is moved along the slot80from the starting section81in the direction towards to the end section82. The shape of the slot80is now configured in such a way that a reverse movement of the positioning element24or of the bolt85at least in the (fully) activated position or active position22of the restraint device20is prevented. The difference between the embodiment variant which is shown inFIGS. 23a,23band23cand the embodiment variant which is shown inFIGS. 23d,23eand23fis based essentially in the shape of the slot80, wherein the embodiment variant according toFIGS. 23a,23band23chas a more bent shape of the slot80while the embodiment variant according toFIGS. 23d,23eand23fhas a more curved shape of the slot80. The locking lever84in this case can be pretensioned or spring-preloaded in the direction of its position which corresponds to the inactive position.

According to a further embodiment variant of the locking means25, which is shown inFIGS. 23g(inactive position) and23h(active position), instead of the slot80(according to the previously described embodiment variant) an operating cam80′, also with a starting section and an end section82′ for the bolt85, is provided, wherein the operating cam has a recess in the end section in such a way that the bolt85, which is moved with the positioning element24, can also no longer be moved back into the starting section, or such a reverse movement is highly improbable, on account of the force ratios which exist in an accident situation. The locking lever84in this case can also be pretensioned or spring-preloaded in the direction of its position which corresponds to the inactive position.

According to a further embodiment variant of the locking means25, which is shown inFIGS. 23i(inactive position) and23j(active position), the slot80is formed with a starting section81which has a reduced clear opening, and an end section82which has an enlarged clear opening, in such a way that the bolt85has a smaller diameter in a first axial section85′ and interacts with the starting section81, and that the bolt85, upon reaching the end section82of the slot80(which is to be carried out during a movement of the positioning element24in the direction of the active position22), is pressed with a second axial section85′ of the bolt, which has a larger diameter, into the end section82on account of an axial spring-pretensioning of the bolt due to a spring element86.

According to a further embodiment variant of the locking means25, which is shown inFIGS. 23k(active position) and23l(inactive position), it is provided that the positioning element24interacts with the upper section46, especially with holes or recesses46′ in the upper section46, in such a way that upon reaching the active position22a reverse movement of the positioning element24is prevented. In this case, it is especially provided that the positioning element24has locking lugs24′″ for engaging in the recesses46′ of the upper section. Furthermore, it can be additionally provided that the upper section46has a stop for limiting the positioning movement of the positioning element24, for example an adapted flange.

List Of Designations