GB2396336A

GB2396336A - Airbag housing with ignition cable tie

Info

Publication number: GB2396336A
Application number: GB0229665A
Authority: GB
Inventors: Murray Alec Ingram
Original assignee: Autoliv Development AB
Current assignee: Autoliv Development AB
Priority date: 2002-12-19
Filing date: 2002-12-19
Publication date: 2004-06-23
Anticipated expiration: 2022-12-19
Also published as: GB0229665D0; GB2396336B

Abstract

An airbag housing comprises a body 6 having an element 10 spaced apart from a position where a flexible cord 12 extends from the body 6, wherein a free end 14 of the cord 12 may be inserted through an aperture 11 in the element 10, which is configured to prevent subsequent cord 12 withdrawal. The inserted cord 12 can secure an ignition cable 4 to the body, to prevent wiring damage or disconnection due to handling during airbag module installation in a vehicle. The body 6 preferably has an outer face 7 provided with a groove 8 for the cable 4. The element 10 may be a lug with a deformable aperture 11. The cord 12 may be serrated and located on the opposite side of the groove 8 to the lug 10. The housing may comprise a plurality of such lugs and cords.

Description

DESCRIPTION OF INVENTION

IMPROVEMENTS IN OR RELATING TO HOUSINGS FOR AIR-BAG

UNITS 10 THE PRESENT INVENTION relates to a housing for an air-bag unit. More particularly, the present invention relates to a housing for an airbag unit, the air-bag unit having an ignition cable for electrical connection to a motor vehicle electrical system.

15 It is well known to provide motor vehicles with air-bags to be inflated in the event of an accident, in order to prevent injury to the occupants of a motor vehicle. Each air-bag is typically provided as an individual air-bag unit in which a folded inflatable air-bag, a gas generator and an ignition squib are provided within an air-bag housing. The ignition squib is electrically connected 20 to an ignition cable, and the cable passes out of the housing so as to be electrically connectable to the electrical system of a motor vehicle. However, in order to avoid disconnection of the electrical connection between the ignition cable and the squib, it is necessary to secure the ignition cable to the air-bag housing so that should the cable become snagged, caught or pulled, for example 25 during transportation, storage or installation of the air -bag unit, the electrical connection remains intact.

Previously proposed arrangements to secure the ignition cable of such an air-bag unit to the air-bag housing typically only serve to grip the cable properly

when the air-bag housing is finally closed around the internal components of the air-bag unit. For example, an air-bag housing can take the form of two housing parts which are secured and sealed to one another so as to enclose the internal components of the air-bag unit. Such an arrangement can be 5 configured to grip the ignition cable between gripping regions of the two housing parts. However, it will be appreciated that this arrangement does not properly grip or secure the ignition cable to the housing until the two parts of the housing are finally secured to one another, which can be disadvantageous during manufacture of the air-bag unit.

It is therefore an object of the present invention to provide an improved housing for an air-bag unit having an ignition cable.

Accordingly, the present invention provides a housing for an airbag unit 15 having an ignition cable, the housing comprising: a housing body having a cable securing tie to secure said cable to the housing body; the cable securing tie comprising: an elongate, flexible cord having a first end secured to the housing body; and an element defining an aperture spaced from the first end of the cord by a distance sufficient to accommodate the cable between the aperture 20 and the cord, the aperture being configured to receive and engage the opposite, free end of the cord and to prevent subsequent withdrawal of the cord from the aperture after the cord has been drawn up against the cable passing between the aperture and said first end of the cord.

25 Preferably, the housing body defines a channel between said aperture and said first end of the cord to receive a length of said ignition cable.

Advantageously, said channel is substantially arcuate in cross-section.

Conveniently, said aperture is formed through a lug projecting outwardly from said housing body.

5 Preferably, said lug is moulded integrally with said housing body.

Conveniently, the flexible cord is integrally formed with the housing body. 10 Advantageously, said flexible cord is provided with a plurality of serrations configured to pass through said aperture in a first insertion direction but to engage said aperture and prevent withdrawal of said cord in a withdrawal direction. 15 Preferably, the element defining the aperture is of resilient material.

Conveniently, said housing comprises a plurality of said cable securing ties. 20 So that the present invention may be more readily understood, and so that further features thereof may be appreciated, an embodiment of the invention will now be described by way of example, with reference to the accompanying drawings, in which: 25 FIGURE 1 is a perspective view of a known air-bag unit having an ignition cable for connection to a motor vehicle electrical system; FIGURE 2 is a perspective view of a section of an air-bag housing in accordance with the present invention, provided with a cable securing tie to secure an ignition cable to the housing body;

FIGURE 3 is a view corresponding generally to that of Figure 2, illustrating an ignition cable about to be secured to the housing body by the cable securing tie; and FIGURE 4 is a view corresponding generally to that of Figure 3, 5 illustrating the cable securing tie in a configuration in which it secures the ignition cable to the housing body.

Referring in initially to Figure 1, there is illustrated an air-bag unit 1 of a type known per se. The particular air-bag unit 1 illustrated is configured to lO deploy a "side air-bag" and it is therefore configured to be installed, for example, in the trim of a side door, or in the side of a passenger seat, so that the air-bag, when deployed, is located between a passenger and the side of a motor -vehicle. 15 The air-bag unit 1 comprises a housing 2 which typically comprises two housing parts secured and sealed together so as to enclose within the housing a folded air-bag, a gas generator and an ignition squib. The ignition squid is electrically connected to a plurality of ignition wires 3 passing out of the housing 2 and which are bound together and led away from the housing 2 as an 20 insulated ignition cable 4. The ignition cable 4 terminates with an electrical connector 5 which is configured for electrical connection to the electrical system of a motor vehicle.

In order to actuate the air-bag unit 1, an appropriate ignition signal is fed 25 to the ignition squib along the cable 4, so that the ignition squib can be activated in order to trigger deployment of the air-bag.

It should be appreciated from the illustration of Figure 1, that if the ignition cable 4 becomes snagged or caught on an obstruction or such like

during transportation or storage of the air-bag unit 1, the ignition wires 3 can quite easily become detached, thereby becoming electrically disconnected from the ignition squib 2. It has also been found, in practice, that technicians producing or installing air-bag units such as that illustrated in Figure 1, often 5 card the entire air-bag unit 1 simply by grasping the ignition cable 4 and allowing the relatively heavy housing 2 to dangle from the cable 4 which can, again, cause the ignition wires 3 to become disconnected.

Turning now to consider Figures 2 to 4, there is illustrated a section of 10 the outer wall 6 of an air-bag housing in accordance with the present invention.

The outer face of the side wall 6 is indicated at 7.

The side wall 6 of the air-bag housing of the present invention is preferably moulded from plastics material and is moulded so as to define an 15 inwardly-directed groove or channel 8 which is shown extending upwardly from a lowermost edge 9 of the side wall 6. The channel or groove 8 has a uniform and substantially arcuate cross-section.

At a position along the lowermost edge 9 of the housing side wall 6, 20 there is provided an integrally moulded lug 10 which projects outwardly from the side wall 6, and which is located immediately adjacent one side of the channel 8. A generally key-hole-shaped aperture 11 is provided through the lug 10. The lug 10 is resiliently deformable so that the keyhole-shaped aperture 1 1 can be deformed out of its initial shape as illustrated.

Projecting outwardly from the housing side wall 6 on the opposite side of the channel 8 to the lug 10, there is provided an integrally moulded flexible cord 12 having a plurality of serrations 13 provided along at least part of its length. The flexible cord 12 terminates with a free end 14 which, as will be

described below, is sized so as to be freely insertable through the keyhole shaped aperture 11 formed through the lug 10. As will become clear, the lug 10 and the flexible cord 12 together serve as a cable-securing tie to secure an ignition cable to the side wall 6 of the housing.

The ignition cable 4 is illustrated in Figure 3 in position ready to be secured to the side wall 6 of the housing. The ignition cable 4 is received within the channel 8 so as to lie between the lug 10 and the flexible cord 12.

Although not illustrated, the ignition cable 4 extends upwardly from the 10 lowermost edge 9 of the housing side wall 6 and passes into the housing through an aperture formed in the side wall 6. This aperture is preferably formed within the channel 8, or at a position at which the channel 8 terminates.

It will be seen from Figure 3 that the cable 4, although received and 15 partially accommodated within the channel 8 stands proud of the outer wall surface 7.

In order to secure the ignition cable 4 to the side wall 6 of the housing, the free end 14 of the flexible cord 12 is inserted through the key-holeshaped 20 aperture 11 "hereafter it is pulled sharply so as to draw at least some of the serrations 13 through the key-hole-shaped aperture 11 (as illustrated in Figure 4), until the flexible cord 12 is drawn up tightly against the ignition cable 4 so as to trap the ignition cable 4 tightly between the flexible cord 12 and the channel 8.

As clearly illustrated in Figure 3, the serrations 13 are shaped so as to be relatively easily pulled through the key-hole-shaped aperture 11, by deforming the aperture 11. However, because of the relative size of the key-hole-shaped aperture 11 and the serrations 13, as the serrations 13 are pulled through the

key-hole-shaped aperture 11, the aperture 11 is caused to deflect and deform, so as to allow the passage of the serrations 13 therethrough. However, each serration 13 is shaped so as not to freely pass through the aperture 11 in a withdrawal direction, so that when the flexible cord 12 is drawn up tightly 5 against the ignition cable 4 illustrated in Figure 4, it will not subsequently become loose. It will therefore be understood that the aperture 11 and the flexible cord 12 are configured to engage one another to prevent subsequent withdrawal of the cord from the aperture after the cord has been drawn up tightly against the cable.

It will therefore be understood that the above-described air-bag housing of the present invention provides a simple and convenient arrangement to secure an ignition cable 4 to the housing, at a position spaced from the electrical connection (inside the housing) between the cable and the ignition 15 squid. This arrangement therefore helps to prevent inadvertent disconnection of the ignition cable 4 from the squib during transportion, storage and installation of the air-bag unit. However, because the described arrangement of the present invention serves to secure the cable 4 against only one part of the housing, the cable 4 can be secured in position with respect to the housing even 20 before the housing is finally closed around the internal components for the air-

bag unit. This allows the cable 4 to be tightly secured to the housing during the production process of the actual air-bag unit.

It should also be noted that the cable-securing tie arrangement of the 25 described embodiment of the present invention is effective in securing cables of a range of different diameters to the air-bag housing. The cord 12 can be drawn up tightly against any cable housing a diameter greater enough to stand proud of the outer wall surface 7.

If desired, a plurality of the cable-securing ties may be provided.

Although the present invention has been described above with particular 5 reference to a particular preferred embodiment, it has been envisaged that certain modifications or alterations could be made to the arrangement, without departing from the scope of the present invention. For example, although the above-described embodiment is provided with a key-hole-shaped aperture 11 and a plurality of appropriately-shaped serrations on the flexible cord 12, other 10 forms of aperture and cord could be provided to ensure that the cord is relatively freely insertable through the aperture in a first insertion direction, but to prevent subsequent withdrawal of the cord through the aperture 11 in a withdrawal direction. For example, the lug 10 could be provided with a deformable locking element configured to engage suitable locking formations 15 provided along the cord 12.

In the present specification "comprises" means "includes or consists oft'

and "comprising" means "including or consisting of".

20 The features disclosed in the foregoing description, or the following

claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse 25 forms thereof.

Claims

CLAIMS:

1. A housing for an airbag unit having an ignition cable, the housing comprising: a housing body having a cable securing tie to secure said cable to the housing body; the cable securing tie comprising: an elongate, flexible cord having a first end secured to the housing body; and an element defining an 10 aperture spaced from the first end of the cord by a distance sufficient to accommodate the cable between the aperture and the cord, the aperture being configured to receive and engage the opposite, free end of the cord and to prevent subsequent withdrawal of the cord from the aperture after the cord has been drawn up against the cable passing between the aperture and said first end 15 of the cord.

2. A housing according to claim 1, wherein the housing body defines a channel between said aperture and said first end of the cord to receive a length of said ignition cable.

3. A housing according to claim 2, wherein said channel is substantially arcuate in cross-section.

4. A housing according to any one of the preceding claims, wherein said 25 aperture is formed through a lug projecting outwardly from said housing body.

5. A housing according to claim 4, wherein said lug is moulded integrally with said housing body.

6. A housing according to any one of the preceding claims, wherein the flexible cord is integrally formed with the housing body.

5

7. A housing according to any one of the preceding claims, wherein said flexible cord is provided with a plurality of serrations configured to pass through said aperture in a first insertion direction but to engage said aperture and prevent withdrawal of said cord in a withdrawal direction.

10

8. A housing according to claim 7, wherein the element defining the aperture is of resilient material.

9. A housing according to any one of the preceding claims comprising a plurality of said cable securing ties.

10. A housing for an airbag unit substantially as hereinbefore described with reference to and as shown in figures 2 to 4 of the accompanying drawings.

11. Any novel feature or combination of features disclosed herein.