Tensioning device for a safety belt component

Abstract

The invention relates to a tensioning device for a safety belt component, having a gas generator (1) for generating a compressed gas, a piston (2) which is driveable by the compressed gas, a traction cable (3) which is attached to the piston (2) and is connectable to a safety belt component to be set into a tensioning movement, a tensioner tube (4) for receiving and guiding the piston (2), the tensioner tube (4) having between the gas generator (1) and the piston (2) a cutout (5) in its casing, and a cable guide (6) which projects through the cutout (5) into the tensioner tube (4) and with which the traction cable (3) is led out of the tensioner tube (4) through the cutout (5), the cable guide (6) consisting of at least two, preferably precisely two parts (6.1, 6.2).

Description

[0001] Tensioning device for a seat belt component

[0002] The present invention relates to a tensioning device for a safety belt component, comprising a gas generator for generating a compressed gas, a piston which can be driven by the compressed gas, a pull cable which is connected to the piston and which can be connected to a safety belt component which is to be set in a tensioning movement, and a tensioning tube for receiving and guiding the piston.

[0003] Such a tensioning device is known, for example, from DE 10 2015 1 1 1 083 B4, in which the piston is guided in a tensioning tube. The tensioning tube is connected to a deflection block manufactured using a die-casting process, which forms a cable deflection for the traction cable, a receptacle for the gas generator, and a pressure chamber into which the compressed gas generated by the gas generator flows. The deflection block, connected to the front of the tensioning tube, requires a relatively expensive component that also requires a relatively large amount of space.

[0004] Therefore, WO 2021 / 160 569 A1 discloses a tensioning device in which the gas generator is arranged within the linear tensioning tube. A recess is formed in the casing of the tensioning tube, through which the traction cable is guided out of the tensioning tube. For guiding the traction cable out of the tensioning tube, a cable deflection device is disclosed, which is constructed in several parts. A component referred to as the guide part, with a receptacle for the gas generator, can be inserted into the tensioning tube, and a component referred to as the fixing part protrudes from the outside through the recess, so that the traction cable is guided through the recess by means of the fixing part, also referred to below as the cable guide.

[0005] According to WO 2021 / 160 569 A1, the cable guide, referred to as the fixing part, is formed as a single piece. To assemble the tensioning device, the end of the tension cable facing away from the seat belt component is first threaded through the single-piece cable guide, then inserted through the recess in the guide part and into the tensioner tube. The tension cable is then pulled over the end of the tensioner tube, with the piston and the fastening element then being applied to the tension cable, which is then pressed together with the tension cable. The end of the tension cable associated with the seat belt component is then pulled, so that the piston and the fastening element return to their initial state.Because the end of the seat belt component comes into contact with the cable guide threaded onto the tension cable during assembly, the length to which the tension cable can be pulled out of the tensioner tube for pressing on the fastener is limited. This also limits the tensioning travel.

[0006] The object of the present invention is therefore to at least partially eliminate the disadvantages described with reference to the prior art and in particular to provide a tensioning device and a method for producing a tensioning device with which a longer tensioning path is possible.

[0007] The object is achieved in particular by a method for producing a tensioning device, comprising the following steps in the specified order: a) providing a tensioning tube which has a recess in its casing and is in particular straight, b) introducing a traction cable into the tensioning tube, wherein the traction cable is guided through the recess, in particular from the outside, into the tensioning tube, c) fastening a fastening to the traction cable, for example by pressing the fastening with the traction cable, d) attaching a multi-part cable guide to the traction cable on a section of the traction cable which projects beyond the recess, wherein the traction cable is partially surrounded by the multi-part cable guide, e) inserting the cable guide into the recess.In other words, the method essentially provides for the traction cable to first be inserted through the recess into the tensioner tube. The element that transmits the force from the piston to the traction cable in the event of deployment (i.e., the fastening element) is then first secured to the traction cable. Only then is the cable guide attached to a section of the traction cable outside the tensioner tube, which section is formed between the recess and the end associated with the seat belt component. For this purpose, the cable guide is constructed in several parts so that the traction cable does not have to be threaded through the cable guide before being inserted into the tensioner tube. This allows for a greater tensioning path even with otherwise identical dimensions.

[0008] In particular, it is also proposed that, prior to step b), a guide part is inserted into the tensioner tube from one end face, wherein preferably a gas generator is pre-assembled in the guide part and, in step e), the cable guide is brought into engagement with the guide part.

[0009] Accordingly, the object is also achieved by a tensioning device having the features mentioned at the outset, in which the tensioning tube has a recess in its casing between the gas generator and the piston and in which a cable guide is provided which projects through the recess into the tensioning tube and with which the traction cable is guided out of the tensioning tube through the recess, wherein it is provided that the cable guide consists of at least two, preferably exactly two parts.

[0010] In other words: The invention proposes that the cable guide, i.e. the component of the tensioning device with which the traction cable is guided through the recess into the tensioning tube, is designed in several parts, wherein the parts of the cable guide are arranged and designed such that they surround the traction cable in its circumferential direction when assembled to one another, so that the cable guide can be attached to the traction cable and the traction cable does not have to be threaded through an opening in the cable guide. The (sectional) planes at or along which the parts of the cable guide abut one another therefore extend (at least virtually) into the region of an opening through which the traction cable extends when the cable guide is assembled. It is thus possible to attach the cable guide to the traction cable after the traction cable has been inserted with a free opening through the recess into the tensioning tube.This makes it possible to attach the rope guide to the traction rope at a later point in the manufacturing process, which in turn allows for a greater tensioning path with otherwise identical dimensions.

[0011] The parts of the rope guide are also designed in such a way that the traction rope can come into contact with the parts of the rope guide when installed.

[0012] In one embodiment, it can be provided that the at least two, preferably exactly two, parts abut one another along a plane that runs parallel to a longitudinal axis of the tensioning tube. Alternatively or additionally, it can be provided that the at least two parts abut one another along a plane that runs transversely, in particular orthogonally, to a longitudinal axis of the tensioning tube.

[0013] In both cases, the two parts of the rope guide can be attached to the pull rope from opposite directions.

[0014] In one embodiment, it can be provided that the second part is / will be arranged between two sections of the first part. In this case, it is possible to insert the traction cable between the two sections of the first part and then slide the second part between the two sections, whereby the second parts can be fastened together using suitable means, for example, with a bolt extending through the two sections of the first part and through the second part. In this case, the two parts are secured to one another or immovably fixed to one another with an additional element.

[0015] In an alternative embodiment, however, it can also be provided that the two parts are secured to one another in a form-fitting and / or force-fitting manner, preferably exclusively in a form-fitting manner. For this purpose, the two parts can have complementary projection and recess configurations that interlock for securing. For example, hook-shaped, elastically deflectable elements can be formed on one part, which engage in corresponding recesses in the other part.

[0016] In order to further simplify the manufacturing process and avoid mixing up components, it can also be provided that the two parts of the cable guide are connected to each other via a film hinge so that the two parts can be folded towards each other for attachment to the traction cable.

[0017] It can also be provided that a section of the first part extends along the second part on only one side. In this context, it can be provided, in particular, that the same second part can be used for different first parts, wherein the two first parts differ from each other in that the sections extending along the second part are arranged on opposite sides of the second part. Depending on the subsequent installation situation of the tensioning device, either the first or second alternative of the first part can then be used, while the second part remains structurally identical.

[0018] The invention particularly relates to tensioning devices in which the tensioning tube has a recess in its casing between the gas generator and the piston, and in which the tensioning device comprises a cable guide that extends through the recess into the tensioning tube and guides the traction cable through the recess. Thus, the die-cast deflection block can be dispensed with.

[0019] It is particularly provided that the cable guide engages with the section engaging in the tensioner tube in the guide part, whereby on the one hand the guide part is fixed in its position in the tensioner tube and on the other hand a passage of the pull cable through the recess is made possible without the pull cable coming into contact with an edge of the recess formed by the tensioner tube. The gas generator is in particular arranged inside the tensioner tube, wherein it can preferably be provided that the guide part has a receptacle, wherein the gas generator is arranged in the receptacle. In this context it is particularly provided that the guide part is designed such that the compressed gas generated by the gas generator is guided along the pull cable inside the tensioner tube to the piston without the pull cable being subjected to the compressed gas in the region of the guide part.

[0020] The recess for the traction cable and the cable guide is arranged in particular in a straight section of the tensioning tube, wherein it is provided in particular that the tensioning tube is designed to be straight over its entire extent.

[0021] The invention and the technical environment are explained below using the figures as examples. They show schematically

[0022] Figure 1 : an exploded view of a tensioning device,

[0023] Figure 2: a sectional view along the longitudinal axis of a

[0024] tensioner tube through the tensioning device and

[0025] Figures 3 to 10: different designs for the multi-part rope guide.

[0026] The tensioning device shown in Figures 1 and 2 comprises a tensioner tube 4 and a pull cable 3 for a seat belt component. A recess 5 is formed in the tensioner tube 4, through which the pull cable 3 is guided by means of a cable guide 6. Within the tensioner tube 4, a piston 2 is arranged on the pull cable 3, with a fastening 8 being pressed onto the pull cable 3 and resting against the piston 2. Also arranged within the tensioner tube 4 is a guide part 7, which forms a receptacle for a gas generator 1. In the assembled state, the gas generator 1 is thus also arranged in the tensioner tube 4.

[0027] As can be seen in particular from Figure 2, the cable guide 6 engages in the guide part 7 in the assembled state, whereby the traction cable 3 is guided through the guide -

[0028] REVISED SHEET (RULE 91) ISA / EP tensioning part 7. The cable guide 6 is fixed by means of a clamp 10 surrounding the tensioner tube 4, for which purpose bolts 11 are provided which pass through the cable guide 6 and the clamp 10.

[0029] When triggered, the gas generator 1 generates a pressurized gas, which is guided through the guide part 7 along the pull cable 3 to the piston 2 without coming into contact with the pull cable 3. The pressurized gas drives the piston 2 (to the right in Figure 2), with the piston 2 resting against the fastening 8 at its end facing away from the gas generator 1. The tensioning device can thus be used to retract a safety belt component (such as an end fitting or belt buckle) that can be connected to the pull cable 3.

[0030] As will be explained below with reference to the exemplary embodiments in Figures 3 to 10, the cable guide 6 is constructed in several parts, which makes it possible for the cable guide 6 to be applied to the traction cable 3 after the end of the traction cable 3 which will later be connected to the fastening 8 has already been inserted through the recess 5 into the tensioning tube 4. This also makes it possible, however, for the traction cable 3 to be pulled out of the tensioning tube 4 somewhat further through the right-hand end shown in Figure 2 in order to attach the fastening 8, than if the cable guide had already been threaded onto the traction cable 3, as would be necessary with a one-piece design of the cable guide.

[0031] The cable guide 6 comprises, in particular, a first part 6.1 and a second part 6.2. The first part 6.1 and the second part 6.2 can each have at least one through-opening through which a bolt 11 for fixing the parts 6.1 and 6.2 to the tensioner tube 4 can be guided.

[0032] According to the embodiment of Figure 3, the first part 6.1 and the second part 6.2 are separated from each other along a plane that runs orthogonally to a longitudinal axis of the tensioner tube 4. The parts 6.1 and 6.2 each have a through-opening through which a bolt 11 can be pushed in order to fix the cable guide 6 to the tensioner tube 4 and to the

[0033] 7

[0034] REVISED SHEET (RULE 91) ISA / EP clamp 10. The first part 6.1 is secured to the second part 6.2 by means of a snap connection, for which purpose parts 6.1 and 6.2 have corresponding hooks and recesses.

[0035] According to the embodiments of Figures 4 and 5, the first parts 6.1 each have two parallel sections, between which the second part 6.2 is arranged. The second part 6.2 has a through-hole which, when assembled, is aligned with through-holes in the parallel sections of the first part 6.1, so that a bolt can be passed through the through-holes. To assemble the cable guide 6, the first part 6.1 is first slipped onto the traction cable 3, and then the second part 6.2 is placed between the parallel sections of the first part 6.1 and secured there.

[0036] According to the embodiments of Figures 6 and 7, the first part 6.1 and the second part 6.2 have mutually corresponding form-locking configurations such that the two parts 6.1 and 6.2 can be connected to one another by sliding the form-locking configurations into one another, wherein the displacement direction runs parallel to the traction cable 3 arranged between the parts.

[0037] According to the embodiment of Figure 8, the first part 6.1 has a lateral recess through which the first part 6.1 can be placed onto the traction cable 3. The lateral recess can then be closed again by attaching the second part 6.2, so that the traction cable 3 is guided through the cable guide 6 consisting of the two parts 6.1 and 6.2.

[0038] According to the embodiment of Figure 9, a section of the first part 6.1 extends along one side of the second part 6.2, wherein a through-opening in the section extending along the second part 6.2 is aligned with a through-opening in the second part 6.2. The second part 6.2 can also be used with a first part 6.1 in which the section extending parallel along the second part 6.2 is arranged on the opposite side. Thus, the second part

[0039] 6.2 may be used with different first parts 6.1 depending on the installation situation of the tensioning device.

[0040] According to the embodiment of Figure 10, the first part 6.1 and the second part 6.2 are connected to each other via a film hinge 9. The first part 6.1 and the second part 6.2 can thus be folded onto each other, with the pull cable 3 being arranged between the parts 6.1 and 6.2. This has the advantage that the two parts 6.1 and 6.2 are already permanently connected to each other before assembly, which makes the assembly process more reliable.

[0041] List of reference symbols

[0042] 1 gas generator

[0043] 2 pistons

[0044] 3 pull rope

[0045] 4 tensioner tube

[0046] 5 Recess

[0047] 6 Rope guide

[0048] 6.1 first part

[0049] 6.2 second part

[0050] 7 Guide part

[0051] 8 Fastening

[0052] 9 film hinge

[0053] 10 clamps

[0054] 1 1 bolt

Claims

Claims 1. Tensioning device for a safety belt component, with a gas generator (1) for generating a compressed gas, a piston (2) that can be driven by the compressed gas, a traction cable (3) that is connected to the piston (2) and that can be connected to a safety belt component that is to be set in a tensioning movement, a tensioning tube (4) for receiving and guiding the piston (2), the tensioning tube (4) having a recess (5) in its casing between the gas generator (1) and the piston (2), and a cable guide (6) that projects through the recess (5) into the tensioning tube (4), with which the traction cable (3) is guided out of the tensioning tube (4) through the recess (5), characterized in that the cable guide (6) consists of at least two, preferably exactly two parts (6.1, 6.2).

2. Tensioning device according to claim 1, wherein the at least two parts (6.1, 6.2) are designed such that the at least two parts (6.1, 6.2) surround the traction cable (3) in its circumferential direction when mounted to one another.

3. Tensioning device according to one of the preceding claims, wherein the traction cable (3) can be brought into contact with the at least two parts (6.1, 6.2).

4. Tensioning device according to one of the preceding claims, wherein the at least two parts (6.1, 6.2) abut one another along a plane which runs parallel to a longitudinal axis of the tensioning tube (4).

5. Tensioning device according to one of the preceding claims, wherein the second part (6.2) is arranged between two sections of the first part (6.1).

6. Tensioning device according to one of the preceding claims, wherein the at least two parts (6.1, 6.2) abut one another along a plane which runs transversely, in particular orthogonally, to a longitudinal axis of the tensioning tube (4).

7. Tensioning device according to one of the preceding claims, wherein the at least two parts (6.1, 6.2) abut one another along a first plane which runs parallel to a longitudinal axis of the tensioning tube and along a second plane which runs orthogonal to a longitudinal axis of the tensioning tube.

8. Tensioning device according to one of the preceding claims, wherein a portion of the first part (6.1) extends along the second part (6.2) on only one side.

9. Tensioning device according to one of the preceding claims, wherein the at least two parts (6.1, 6.2) are fixed to one another in a form-fitting and / or force-fitting manner.

10. Tensioning device according to one of the preceding claims, wherein two parts (6.1, 6.2) of the cable guide are connected to one another via a film hinge (9). 1 1. Method for producing a tensioning device, comprising the following steps in the specified order: a) providing a tensioning tube (4) having a recess (5) in its casing and in particular being straight, b) introducing a traction cable (3) into the tensioning tube (4), the traction cable (4) being guided through the recess (5), c) fastening a fastening (8) to the traction cable (3), d) attaching a multi-part cable guide (6) to the traction cable (3) outside the tensioning tube (4) on a section of the traction cable (3) projecting beyond the recess (5), the traction cable (3) being partially surrounded by the cable guide (6), e) inserting the cable guide (6) into the recess (5).

12. The method according to claim 1 1, wherein before step b) a guide part (7) is inserted from an end face into the tensioner tube (4), wherein preferably a gas generator (1) is pre-assembled in the guide part (7), wherein in step e) the cable guide (6) is brought into engagement with the guide part (7).

Images