End fitting tensioner

Abstract

End fitting tensioner for a belt system of a motor vehicle, comprising a tube (2) with a tensioning device arranged therein, wherein the tube (2) has a fastening section (5) for attachment to a supporting structure of the motor vehicle, wherein a connecting element (7) for fastening the tube (2) to the supporting structure in a second fastening point is provided on the outside (6) of the tube (2), which can be fastened to the tube (2) in different longitudinal and / or circumferential positions of the tube (2).

Description

[0001] The invention relates to an end fitting tensioner for a belt device of a motor vehicle, comprising a tube with a tensioning device arranged therein, wherein the tube has a fastening section for fastening the end fitting tensioner to a support structure of the motor vehicle at a first fastening point, wherein on the outside of the tube a connecting element for fastening the tube to the support structure is provided in a second fastening point, which connecting element can be fastened to the tube in different longitudinal and / or circumferential positions of the tube.

[0002] Such an end fitting pretensioner is used to quickly eliminate slack in a motor vehicle seat belt in the event of a collision. This is done by tightening the seat belt via the end fitting pretensioner, i.e. pulling it tighter. This ensures that the person secured to the seat by the seat belt is more firmly secured to the seat or is retracted and fixed in the sitting position. Modern motor vehicles are usually equipped with three-point seat belts that are attached to the vehicle at three points and have a lap belt section on the one hand and an upper body section running diagonally across the torso on the other. The belt has a spring-loaded belt retractor that rolls up the belt webbing under spring load and from which it can be unwound, as well as a buckle plate that can be anchored in a belt buckle.An end fitting tensioner can be coupled to the belt retractor on the one hand, to the belt buckle on the other hand, or to the belt strap itself, for example the end of the lap belt section, which is fixed to a tab of the end fitting tensioner.

[0003] An end fitting tensioner usually comprises a tube in which a pyrotechnically triggered tensioning device is arranged, via which a pull cable or similar tension element connected to the belt device, for example the end of the lap belt section, can be moved axially into the tube to tighten the belt. If a pyrotechnic propellant is ignited in the event of a collision, its ignition shoots a piston element guided in the tube and connected to the pull cable along the tube, resulting in an immediate pulling movement via the pull cable on the belt to tighten it. This tube must be fixed accordingly on the vehicle side, i.e., secured in a defined position, for which purpose it is connected to a supporting structure of the motor vehicle, usually the body or a sheet metal body component.For this purpose, the pipe has a fastening section with which the pipe is fixed to the supporting structure at a first fastening point, usually by screwing. Since the pipe is of a corresponding length, it must also be connected to the supporting structure at a second fastening point, remote from the first fastening point, for example, via a screw connection, for which a second fastening section must be provided on the pipe.While the first fastening section can ultimately be designed the same across all models, since its connection to the supporting structure can be made in the same way across all models and at a first fastening point on the supporting structure that is the same across all models, the second fastening section and thus ultimately the tube as a whole must be designed individually for the respective vehicle model, since the position of the corresponding second fastening point can vary from model to model or the corresponding mounting direction.

[0004] An end fitting tensioner of the type mentioned above is known from US 2012 / 0 146 385 A1. At one end of the tube, a first fastening device for connecting the tube to the body is provided. This first fastening device comprises a sleeve having a transverse bore which is pushed onto the tube. The tube section receiving the sleeve also has a transverse opening so that a fastening screw can be pushed through the transverse bore of the sleeve and the transverse opening of the tube and screwed into the body. Also provided along the tube is a second fastening device in the form of a fastening clip which is pushed onto the tube into a fastening position and which has a laterally projecting fastening section which has a bore through which a fastening screw engages, which is also screwed into the body.

[0005] The invention is therefore based on the problem of providing an improved end fitting tensioner.

[0006] To solve the problem, according to the invention, in an end fitting tensioner of the type mentioned at the outset, the connecting element is fastened by means of at least one tensioning band which engages over the connecting element located on the outside and surrounds the tube.

[0007] The tube of the end fitting tensioner according to the invention is equipped with a separate, detachably attachable connecting element, which connecting element can be fastened to the tube in virtually any longitudinal and / or circumferential position, i.e. the fastening position can be selected as required. This makes it possible to fasten the connecting element to the tube depending on the given installation situation, which, as described, is model-specific, so that the connecting element can be precisely positioned and aligned with respect to a second fastening point provided on the support structure and the tube can be fixed to the support structure accordingly. For installation, therefore, after the connecting element has been fixed to the tube (if this has not already been done), the tube can first be fixed with the connecting element in the second fastening point and then fixed, i.e. screwed, at the first fastening point.This assembly sequence ensures that the pipe does not rotate in the screwing direction when it is screwed in the first assembly position with a high torque. If this risk does not exist, the screw connection can of course also be made first in the first fastening point and then the fixation in the second fastening point. Depending on the design of the connecting element, this fixation can be achieved, for example, by locking or clamping in an opening in the sheet metal support structure, or even by screwing, although this should preferably be avoided in order to make the assembly and fastening process as simple as possible. According to the invention, the end fitting tensioner can therefore be used for various models because the movable connecting element, which can be fastened in different positions, offers a common interface that allows fastening in different support structure positions.The connecting element also offers a uniform interface, as the identical connecting element can be used advantageously for the different models or installation variants.

[0008] The pipe itself preferably has a cylindrical outer surface, meaning it is a cylindrical tube. It is advantageous for the connecting element to have a rounded contact surface for a positive fit on the outer surface. This ensures a larger, firm contact area, as well as guidance of the connecting element on the outer surface of the pipe.

[0009] As described, a central aspect of the present invention is the possibility of detachably and thus positionally adjustable fastening the connecting element to the outside of the pipe. To enable this, the invention provides that the connecting element is fastened by means of at least one tensioning band that engages over the connecting element located on the outside and surrounds the pipe. According to this embodiment of the invention, the fixation is achieved by means of a tensioning band, for example a clamp, preferably made of metal, which surrounds the outside of the pipe and the connecting element and firmly clamps the connecting element against the outside of the pipe.The diameter of such a tensioning band or clamp can be adjusted. To position the connecting element, the tensioning band initially has a correspondingly larger diameter. This diameter is then reduced once the connecting element is in the correct position, so that the tensioning band contracts and firmly clamps the connecting element. Metal tensioning bands or clamps are known which, for example, have a screw element by means of which the diameter can be reduced. The tensioning band is preferably somewhat wider, for example 5 - 15 mm wide, so that it has a correspondingly larger surface area on the pipe and the connecting element. It is of course also conceivable to fix the connecting element not just with one tensioning band, but with two tensioning bands arranged at the longitudinally offset ends of the connecting element.

[0010] To best secure the clamping strap to the connecting element, it is advisable to provide a rounded section on the connecting element that corresponds to the width of the clamping strap, against which the clamping strap rests. This section forms the corresponding rounded contact surface for the clamping strap, which rests flat against it, ensuring secure clamping through appropriate surface pressure.

[0011] To connect the connecting element to the supporting structure, the connecting element can have a connecting section that protrudes radially from the outside and is to be connected to the supporting structure. The connecting element is arranged on the outside of the tube so that the connecting section extends laterally, i.e. radially, from the cylindrical outer surface to the body or supporting structure, where it is secured, so that even shorter distances can be easily bridged.

[0012] To connect the connecting element to the supporting structure, an advantageous development of the invention provides that a groove arrangement and a connecting head delimited by this groove are provided on the connecting sections extending laterally from the outer side, wherein the connecting head, in the assembled position, penetrates an opening in the supporting structure and an opening edge of the supporting structure engages in the groove arrangement. The connecting head thus penetrates the corresponding opening on the supporting structure side, wherein the edge of the opening, which is formed by the sheet metal of the supporting structure, engages in a form-fitting manner in the groove arrangement. This results in a corresponding form-fitting connection, i.e. a type of tongue and groove connection, which results in an extremely stable connection.The significantly wider cross-sectional connection head's penetration through the narrower opening prevents the connection head from slipping out of the opening and the pipe from moving away from the supporting structure. This provides a very simple connection option that eliminates the need for a screw connection, which would be significantly more complex, since it is only necessary to insert the opening edge into the groove arrangement in a suitable manner.

[0013] The groove arrangement itself preferably has at least two grooves running parallel to one another and extending in the longitudinal or transverse direction of the pipe. The opening thus engages with two opposite edges into the groove arrangement or the two grooves. The opening can, for example, be designed as an elongated slot into which the connecting element is inserted, so that the opening edges are introduced into the two grooves. It is also conceivable for the groove arrangement to have four grooves arranged in a rectangular shape. This additionally makes it possible to fix the connecting element in a form-fitting manner not only on two opposite sides, but also on at least one side running orthogonally thereto, into which a further edge section of the opening edge engages, whereby this also serves as a stop, for example when fastening the connecting element by inserting it into the elongated opening.

[0014] As described, it is conceivable that the connecting element or the connecting head is pushed into the opening. For this purpose, the shape of the opening can be designed as a keyhole, with a slightly wider opening section through which the connecting head can be pushed, which wider opening section is followed by a narrower opening section into which the groove arrangement is pushed, so that the edges of this narrower opening section engage in the grooves. Alternatively, it is also conceivable to snap the connecting head into the opening by forcefully pressing it against the supporting structure, i.e. to create a plug-in or snap-in connection. For this purpose, it is advantageous if one or more bevels are provided on the top side of the connecting head.These chamfers, i.e. corresponding beveled surfaces, allow the connecting head to snap into the opening, since the opening edges can slide off these chamfers.

[0015] The connecting element itself is preferably made of plastic, which can also be fiber-reinforced if necessary. It is therefore a simple plastic injection-molded part that can be manufactured extremely cost-effectively, yet simultaneously possesses the appropriate mechanical properties required for secure fixation.

[0016] Further advantages and details of the present invention will become apparent from the exemplary embodiments described below and from the drawings. In the drawings: Fig. 1 a schematic diagram of an end fitting tensioner according to the invention in a first view, Fig. 2 the end fitting tensioner from Fig. 1 in a view rotated by 90°, Fig. 3 a perspective view of the connecting element, Fig. 4 a partial view of the assembled end fitting tensioner showing the connecting element attached to the supporting structure, and Fig. 5 a partial view of a supporting structure with vertically arranged end fitting tensioner.

[0017] Fig. 1 shows an end fitting tensioner 1 according to the invention for a belt device of a motor vehicle. This comprises a tube 2 in which a pyrotechnically triggered tensioning device (not shown in detail) is arranged, with which it is possible to tension a belt device coupled to the end fitting tensioner 1. For this purpose, the end fitting tensioner 1 has a pull cable 3, on which, in the example shown, a tab 4 is arranged, through which, for example, the end of the lap belt section of the belt device is looped and fastened. When the tensioning device is ignited, the pull cable 3 is shot into the tube 2 over almost its entire length, so that the lap belt section is tightened.

[0018] The tube 2 has a first fastening section 5, with which it or the end fitting tensioner 1 is fixed to a supporting structure of the motor vehicle at a first fastening point. For this purpose, the fastening section 5 is preferably screwed on. The supporting structure can be, for example, a pillar, such as the B-pillar of the body for a vertical arrangement of the end fitting tensioner 1, or a sill of the body for a horizontal arrangement of the end fitting tensioner 1.

[0019] In order to fix the end fitting tensioner 1 at a second fastening point on the supporting structure, the end fitting tensioner 1 has a connecting element 7 arranged on the outer side 6 of the tube 2, which is fixed thereto by means of a tensioning band 8 that engages around the connecting element 7 and the tube 2. The tensioning band is a metal tensioning band, e.g. a clamp, which can be tightened accordingly. After the tensioning band 8 can be tightened at any time, the connecting element 7 can therefore be fastened in a variable longitudinal and / or circumferential position on the tube 2 or on the outer side 6, respectively. This means that the position of the connecting element 7 on the tube 2 is variable and its position can be adjusted with respect to a second fastening point provided on the supporting structure.This makes it possible to install the end fitting tensioner 1 on different vehicle models that have differently positioned second fastening positions, thus varying the mounting direction of the end fitting tensioner 1.

[0020] Fig. 3 shows an enlarged view of the connecting element 7, which is a plastic component. The connecting element 7 has an element body 9, which has a rounded contact surface 10 on the side adjacent to the outside, so that a positive contact with the outside 2 is possible. This rounded contact surface extends over the entire length of the connecting element 7 or the element body 9. The element body 9 furthermore has a rounded contact section 11, which is designed in a quasi-groove-shaped manner and into which the tensioning strap 8 is inserted. The contact section 11 is designed according to the width of the tensioning strap 8, which is, for example, between 5 - 15 mm wide, so that the latter is received with its entire surface resting in the groove that defines the contact section 11.

[0021] The element body 9 is further provided with a connecting section 12, which serves as the actual connection to the supporting structure. This connecting section 12 comprises a connecting head 13, which is connected to the element body 9 via a groove arrangement 14. This groove arrangement 14 is designed to be virtually circumferential; it is, for example, a rectangular groove arrangement consisting of two grooves 15 running parallel to one another and in the longitudinal direction of the pipe 2, as well as two grooves 16 running parallel to one another and transverse to the pipe's longitudinal axis. An edge of an opening in the supporting structure engages in this groove, through which the connecting head 13 engages, thereby securing the element to the supporting structure.

[0022] An assembly example shows Fig. 4, in which a section of the pipe 2 with the connecting element 7 attached thereto and the tensioning strap 8 is shown. Also shown is a section of a support structure 17, formed from a metal sheet 18, wherein an opening 19 is provided in the support structure 17, which is delimited by an opening edge 20. In the assembled position, the connecting head 13 engages through the opening 19, while the opening edge 20 visibly engages in the groove arrangement 14. Depending on the design of the opening 19, it is possible that the opening edge of the rectangular opening 19 engages in three grooves, for example the two grooves 15 and one groove 16.This would be the case if the opening were designed to resemble a keyhole and had a widened section through which the connecting head 13 could be pushed without striking the supporting structure, after which the connecting element 7 would be pushed into a narrower opening section, with two opening edges being inserted into the elongated grooves 15. The displacement occurs until the connecting element 7 runs against a transverse opening edge, which then engages one of the grooves 16. In this position, the clamping band 8 is then tightened, and the connecting element 7 is fully anchored.

[0023] Instead of this keyhole design of the opening, it is also conceivable to design the opening as a rectangular opening and to press the connecting head 13 through it, thus creating a snap connection in which the opening edge engages all grooves 15, 16 of the groove arrangement. To achieve this, it is conceivable to form one or more chamfers 21 on the outside of the connecting head 13. These chamfers, when the connecting head 13 is pressed in, run against the groove edge, which slides off until it snaps into the groove arrangement 14.

[0024] While Fig. 4 shows an example of a horizontal fastening, for example on a sill or similar, Fig.5 shows the fastening of the end fitting tensioner 1 by means of the connecting element 7 to a support structure 17 in the form of a B-pillar 22, i.e., vertically positioned, as shown in the figure. The tension cable 3 extends downwards, although only a portion of the tension cable 3 is shown here. It can be seen that the end fitting tensioner 1 is fixed to the support structure 17 via the fastening section 5 at a first fastening point, and to a second fastening point of the support structure 17 via the connecting element 7.

Claims

[1] End fitting tensioner for a belt device of a motor vehicle, comprising a tube (2) with a tensioning device arranged therein, wherein the tube (2) has a fastening section (5) for fastening to a support structure of the motor vehicle, wherein on the outer side (6) of the tube (2) a connecting element (7) for fastening the tube (2) to the support structure is provided in a second fastening point, which connecting element can be fastened to the tube (2) in different longitudinal and / or circumferential positions of the tube (2), characterized by that the connecting element (7) is fastened by means of at least one tensioning band (8) which engages over the connecting element (7) lying on the outer side (6) and surrounds the pipe (2). [2] End fitting tensioner according to claim 1, characterized by that the tube (2) has a cylindrical outer side (6), wherein the connecting element (7) has a rounded contact surface (10) for a positive contact with the outer side (6). [3] End fitting tensioner according to one of the preceding claims, characterized by that a rounded contact section (11) corresponding to the width of the tensioning band (8) is provided on the connecting element (7), against which the tensioning band (8) rests. [4] End fitting tensioner according to one of the preceding claims, characterized by that the connecting element (7) has a connecting section (12) projecting radially from the outside, which is to be connected to the supporting structure. [5] End fitting tensioner according to claim 4, characterized by in that the connecting section (12) has a groove arrangement (14) and a connecting head (13) delimited by this, wherein the connecting head (13) in the assembly position passes through an opening (19) in the support structure and an opening edge (20) of the support structure engages in the groove arrangement (14). [6] End fitting tensioner according to claim 5, characterized bythat the groove arrangement (14) has at least two grooves (15, 16) running parallel to one another and extending in the longitudinal direction or in the transverse direction of the tube (2). [7] End fitting tensioner according to claim 6, characterized by that the groove arrangement (14) has four grooves (15, 16) arranged in a rectangular shape. [8] End fitting tensioner according to one of claims 5 to 7, characterized by that one or more chamfers (21) are provided on an upper side of the connecting head (13). [9] End fitting tensioner according to one of the preceding claims, characterized by that the connecting element (7) is made of a plastic. [10] End fitting tensioner according to claim 9, characterized by that the plastic is fiber-reinforced.

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