Tensioning device for a seat belt part

Abstract

The invention relates to a tensioning device for a safety belt component, comprising: a gas generator (1) for generating a pressurized gas; a piston (2) which can be driven by the pressurized gas; a tensioning cable (3) which is connected to the piston (2) and which can be connected to the safety belt component (4) to be subjected to a tightening movement; a tightening tube (5) for receiving and guiding the piston (2); and a receiver (6) containing the gas generator (1).

Description

[0001] The present invention relates to a tensioning device for a seat belt component, which comprises: a gas generator for generating pressurized gas; a piston which can be driven by the pressurized gas; a tensioning cable which can be connected to the piston and can be connected to the seat belt component to be tightened; a tightening tube for receiving and guiding the piston; and a receiver which accommodates the gas generator.

[0002] Such a tensioning device is known, for example, from DE 10 2020 103 157 A1, in which a receptacle for a gas generator and a cable deflection outside the area exposed to the pressurized gas are formed as a single piece in the guide block. A tightening tube is arranged on the guide block, into which the pressurized gas generated by the gas generator enters when the tensioning device is triggered, so that a piston arranged in the tightening tube is driven by the pressurized gas. On the side facing away from the tightening tube, the cable deflection formed as a single piece in the guide block is shaped so that the tensioning cable can be led out of the guide block in a straight line (if necessary offset in parallel) in the direction of movement of the piston, or alternatively can also be deflected by 90° or more. In order to change the offset of the tensioning cable relative to the direction of movement of the piston or to change the deflection angle by such a design of the guide block, the deflection block must be completely redesigned.

[0003] The object of the present invention is therefore to at least partially eliminate the disadvantages described with respect to the prior art and in particular to provide a tensioning device which can be adapted more easily to different requirements.

[0004] To achieve this object, it is proposed in particular that the tensioning device has a frame which is arranged on the side facing away from the tightening tube and through which the tensioning cable passes after it has protruded from the space of the seat belt component that can be acted upon by the pressurized gas. For example, the frame can be made of a metal sheet which has been formed in particular to have a U-shaped cross section. The frame is used in particular to accommodate additional components of the tensioning device. In particular, components for cable deflection or cable guidance outside the space exposed to the pressurized gas are attached to the frame. Thus, for different applications of the tensioning device, the frame can be designed in the same way, while the components for deflecting the tensioning cable can be adapted to different applications (e.g. deflection by 90° or straight passage).

[0005] The receiver for the gas generator is arranged such that the pressurized gas generated by the gas generator enters the constriction tube and drives the piston there. Preferably, the receiver is arranged in the constriction tube.

[0006] Furthermore, a cable guide may be provided, through which the tensioning cable leaves the tightening tube. The cable guide is arranged in a suitable sealing manner in the tightening tube and preferably also provides a seal along the tensioning cable.

[0007] Preferably, both the receptacle for the gas generator and the cable guide are arranged completely in the constriction tube.

[0008] In order to fix the frame on the tightening tube, it can be provided that the frame can have an engagement section which is arranged in the tightening tube in the installed state. In this case, it can be provided in particular that the engagement section interacts with the cable guide in the installed state and additionally fixes the cable guide in the tightening tube. Thus, the cable guide and the engagement section of the frame are preferably fixed simultaneously by pressing the tightening tube.

[0009] In a preferred embodiment, it is provided that the receiver and the cable guide for the gas generator are formed in one piece, wherein the receiver and the cable guide are arranged completely in the tightening tube.

[0010] Preferably, the tightening tube has a section of circular cross section, in which the piston is arranged and along which the piston is driven by the application of pressure. The tightening tube also has an area whose cross section deviates from the circular cross section. This area preferably has an elliptical cross section. The receiver and the cable guide are particularly arranged in the area of ​​the tightening tube whose cross section deviates from the circular cross section. The receiver for the gas generator is arranged and designed so that the pressurized gas generated by the gas generator is directly introduced into the tightening tube and can therefore directly reach the piston. In particular, the pressurized gas is introduced into the area of ​​the tightening tube where its cross-sectional design changes. Therefore, the pressurized gas is not introduced into the space defined by the cable deflection portion and is guided from there to the piston. This allows the pressurized gas to cool slightly before it comes into direct contact with the tensioning cable arranged in the tightening tube.

[0011] The object stated at the outset is achieved in particular by a tensioning device having the features of independent claim 1. Further solutions and advantageous developments of the tensioning device are given in the above and below description and in the dependent claims, wherein individual features of the advantageous developments can be combined with one another where technically expedient.

[0012] The abovementioned object is achieved in particular by a tensioning device with the features mentioned at the outset, in which the tensioning cable extends through the frame on the side facing away from the tensioner tube and in which the end cap is plugged onto the frame, wherein the end cap engages at least in sections into the frame. The end cap is attached to the frame, in particular from the side facing away from the tensioner tube.

[0013] In other words: In its basic concept, the invention provides that an end cap, in particular consisting of a different material (e.g. plastic), is not only attached to a frame in an overlapping manner, but also has at least one section engaged in the frame, wherein the at least one section engaged in the frame preferably fulfills a function.

[0014] For example, it can be provided that the end cap bears against the frame on the inside with a section engaging the frame and at the same time bears against the outside of the frame on the outside with a section extending over the frame. By placing the end cap not only on the inside but also on the outside, a seal is provided so that hot compressed gas escaping from the pressure chamber along the cable guide cannot or can only escape with difficulty on the side of the tensioning device covered by the end cap.

[0015] In principle, it is conceivable that the end caps surround the frame both on the inside and on the outside only in sections. However, in a preferred embodiment, it is provided that the end caps close the frame circumferentially on the end face facing away from the tensioner tube, so that the end face covered by the end caps and facing away from the tensioner tube is completely closed. For example, if the frame has a U-shaped cross section, the end caps have a U-shaped section that engages into the end caps, while at the same time the end caps have sections that extend on the outside over the U-shaped frame and that rest on the outside against the frame. The regions of the end caps that are arranged between the U-shaped regions are designed in particular to cover the entire surface, so that the end caps completely close the frame on the side facing away from the tensioner tube.

[0016] In addition or as an alternative to the sealing effect of the engagement section, a guide section engaging into the frame can be provided on the end cap, which guide section forms a guide for the tensioning cable. The guide section is designed so that the tensioning cable rests against the guide section in the installed state. In particular, the guide section has a groove-shaped recess, the dimensions of which are adapted to the outer circumference of the tensioning cable. The groove-shaped recess has a curvature in the direction of the tensioning cable, which determines the deflection of the tensioning cable, in particular on the outer side of a curved tensioning cable. In particular, the guide section is configured so that the tensioning cable, if necessary in combination with other elements of the tensioning device, is deflected by approximately 90°.

[0017] Since the end cap can be easily placed on and / or in the frame, the end cap can also be replaced for different purposes of the tensioning device. If, for example, the tensioning cable is guided linearly in the tensioning direction of the piston, the end cap can have, for example, a circular opening as a guide section, through which the tensioning cable is guided out of the frame.

[0018] Furthermore, it can be provided that the section engaged in the frame is designed as a fastening section, wherein the frame, the fastening section and the tensioning cable are coordinated with one another in such a way that the tensioning cable is fastened against unintentional movement by at least one fastening section. This is achieved in particular by the fastening section, the mounted end cap being in contact with the tensioning cable, thereby applying a force which impedes the movement of the tensioning cable. In the absence of such a force, the tensioning cable can still be moved before the final assembly of the tensioning device. On the other hand, the applied force is so small that it does not significantly affect the tightening process.

[0019] In one embodiment, it is provided at this point that at least one guide section of the end cap engaging in the frame is deformed when inserted into the frame and thereby secures the tensioning cable against unintentional movement. Thus, at least one securing section is only deformed during the insertion and in particular at the end of the insertion process, so that a force is exerted on the tensioning cable to secure against unintentional movement. For this purpose, it can be provided in particular that the frame has a corresponding geometric design along which the securing section is inserted into the frame, wherein a deformation of the securing section occurs due to the geometric design. Such a deformation is also understood to be a deflection of the securing section.

[0020] By means of the deformation of the fastening section, the tensioning cable can also be pressed against a further element of the tensioning device, whereby the tensioning cable is clamped between the fastening section and the further element.

[0021] In a particularly preferred embodiment, it is provided that two fastening sections are provided which engage in the frame, wherein the fastening sections are deformed from both sides towards the tensioning cable when inserted. This enables the tensioning cable to be clamped between the two safety sections.

[0022] When designing the section of the end cap that engages in the frame, it can also be provided that the section that physically engages in the frame has several functions. For example, it can be provided that a part of the aforementioned section as a guide section serves on the one hand for guiding the tensioning cables and on the other hand rests on the inner side of the frame and thus forms an inner sealing section.

[0023] The present invention and the technical environment are explained exemplarily below with reference to the accompanying drawings. Schematically, in the accompanying drawings:

[0024] Figure 1 : A perspective view showing the tensioning device,

[0025] Figure 2 : shows an exploded view of the tensioning device,

[0026] Figure 3 : shows a cross-section through the tensioning device,

[0027] Figure 4 : shows a perspective view of the end cap,

[0028] Figure 5 : shows a perspective view of the deflection element, and

[0029] Figure 6 : shows a cross-section through another embodiment of a tensioning device with a straight cable channel,

[0030] Figures 1 to 3The tensioning device shown in the figure comprises a tightening tube 5 in which the piston rod 2 is arranged in the installed state. The piston 2 is firmly connected to a tensioning cable 3 inserted into the tightening tube 5, which is connected to a safety component 4 on its other side for tightening movement.

[0031] The tensioning device also comprises a component in which the cable guide 12 and the receptacle 6 for the gas generator 1 are formed. In the installed state, the component is arranged in the section of the tightening tube 5 having an oval cross section.

[0032] The tensioning device further comprises a frame 7 which, in the mounted state, is arranged with an engagement section located within the tightening tube 5 .

[0033] The deflection element 9 is mounted in the frame 7 by means of bushings 10 which in the mounted state pass through the receptacles 9 . 2 of the deflection element 9 and are arranged on both sides of the deflection element 9 in corresponding openings of the frame 7 , which is U-shaped in cross section.

[0034] The tensioning device also comprises an end cap 8 which is attached to the frame 7 from the side facing away from the tightening tube 5 .

[0035] If especially by Figure 4 It can be seen that the end cap 8 has several sections which are arranged in the frame 7 in the installed state.

[0036] Accordingly, the end cap 8 has a guide section 8 . 1 which is arranged in the frame in the installed state and is channel-shaped and has a curvature in the direction of the tensioning cable.

[0037] The end cap 8 also has an inner sealing section 8.2 which is arranged on the inner side of the frame 7 in the mounted state and abuts against the frame 7. At the same time, the outer sealing section 8.3 abuts against the outer side of the frame 7. By combining the inner sealing section 8.2 and the outer sealing section 8.3, the frame 7 is sealed on the side facing away from the tightening tube 5, so that the pressurized gas escaping from the cable guide 12 cannot escape from the front side of the frame 7, but is deflected.

[0038] Furthermore, the side surfaces of the groove-shaped guide section 8.1 are designed so that when the end cap 8 is inserted, they are pressed on both sides by the frame 7 onto the tensioning cable 3, thereby securing the tensioning cable 3 against accidental movement. Thus, the end cap 8 forms a securing section 8.4. However, the force imposed on the tensioning cable 3 by the securing section 8.4 is not so great that the tightening process is not hindered.

[0039] from Figure 5 It can be seen that the deflection element 9 has an outer surface, referred to as the deflection surface 9.1, which is Figure 3The cross-section shown has a circular shape. The receptacle 9.2 for the bushing 10 is arranged eccentrically with respect to the deflection surface 9.1 and in particular offset towards the deflection surface 9.1.

[0040] The tensioning device further comprises a plug element 11 via which a cable can be connected to the gas generator 1 . The outer contour of the plug element 11 is adapted to the outer contour of the deflection element 9.

[0041] To start the tightening process, the gas generator 1 is ignited, whereby pressurized gas enters the section of the tightening tube 5 with a circular cross section and drives the piston 2 along the tightening tube 5. The driven piston 2 sets the belt part 4 into a tightening movement, wherein the tensioning cable 3 is deflected by the deflection element 9 and the guide section 8.1 of the end cap 8.

[0042] Although in the exemplary embodiment the tensioning cable 3 is deflected by approximately 90°, the tensioning device can also be adapted by replacing a few parts so that the tensioning cable 3 leaves the frame 7 in a linear extension in the direction of movement of the piston 2, such as Figure 6 shown.

[0043] exist Figure 6 In the embodiment of , only the end cap 8 is replaced for this purpose, wherein the guide section will be designed as an opening, through which the tensioning cable 3 protrudes. In order to achieve an optionally different deflection and / or alignment of the tensioning cable 3, the deflection element 9 can also be designed differently.

[0044] The proposed tensioning device can therefore only be adapted for other applications by replacing individual components.

[0045] Reference numerals list

[0046] 1 Gas generator

[0047] 2 Piston

[0048] 3 Tension cables

[0049] 4 Seat belt components

[0050] 5 Tensioner tube

[0051] 6 Receiver

[0052] 7 Framework

[0053] 8 End cap

[0054] 8.1 Boot Segment

[0055] 8.2 Inner sealing section

[0056] 8.3 External sealing section

[0057] 8.4 Fastening section

[0058] 9 Deflection element

[0059] 9.1 Deflection surfaces

[0060] 9.2 Bushing receiving area

[0061] 10 Bushing

[0062] 11 Plug element

[0063] 12 Cable guide

Claims

1. A tensioning device for a seat belt component, the tensioning device comprising: - an inflator (1) for generating pressurized gas, - a piston (2) which can be driven by the pressurized gas, a tensioning cable (3) connected to the piston (2) and connectable to the belt component (4) to be subjected to a tensioning movement, - a tensioner tube (5) for receiving and guiding the piston (2), and - a receiver (6) which accommodates the gas generator (1), It is characterized in that The tensioning cable (3) extends through a frame (7) on the side facing away from the tensioner tube (5), and an end cap (8) is plugged onto the frame (7), wherein the end cap (8) engages at least in sections in the frame (7).

2. The tensioning device according to claim 1, wherein the end cap (8) abuts at least sectionally internally and externally against the edge of the frame (7).

3. The tensioning device according to claim 2, wherein the end cap (8) circumferentially closes the frame (7) on the end face facing away from the tensioner tube (5).

4. The tensioning device according to any of the preceding claims, wherein a guide section (8.1) of the end cap (8) engaged in the frame (7) forms a guide for the tensioning cable (3).

5. The tensioning device according to claim 4, wherein the guide section (8.1) is configured to deflect the tensioning cable by 90°.

6. A tensioning device according to any of the preceding claims, wherein the frame (7), at least one fastening section (8.4) of the end cap (8) engaged in the frame and the tensioning cable (3) are aligned with one another so that the tensioning cable (3) is fastened by the at least one fastening section (8.4) to prevent accidental movement.

7. The tensioning device according to claim 6, wherein the at least one fastening portion (8.4) of the end cap (8) engaged in the frame (7) is deformed when inserted into the frame (7) and thereby fastens the tensioning cable (3) against accidental movement.

8. The tensioning device according to claim 7, wherein the two fastening sections (8.4) of the end cap (8) engaged in the frame (7) are deformed towards the tensioning cable (3) when inserted from both sides.

9. The tensioning device according to any of the preceding claims, wherein the end cap (8) is plugged onto the frame (7) from the end facing away from the tensioner tube (5).

10. The tensioning device according to any of the preceding claims, wherein the frame (7) is formed from sheet metal and is in particular U-shaped in cross section.

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