DE102008017636B4 - Airbag module - Google Patents

Abstract

Airbag module having a housing (20) having an outlet opening (23), into which a gas bag (60) is received, a vehicle-fixed component (30) having a passage opening (32), a cover element (10) with at least one attachment section and a door (13a) having cover portion (12) which closes the passage opening (32) and spans at least a part of the outlet opening (23), wherein the fastening portion is non-positively connected to the vehicle-fixed component (30), and securing means which ineffective in the idle state of the gas bag module However, a detachment of the cover (10) from the vehicle-fixed component (30) during expansion of the gas bag (60) prevent, characterized in that the securing means directly between the cover (10) and the vehicle-fixed component (30) act that attachment means for the cover next to the attachment portion comprise at least a separate component, on Grund whose cover member (10), housing (20) and vehicle-fixed component (30) are non-positively connected to each other, wherein the cover member (10) has a mounting portion which engages under a mounting flange (24) of the housing (20), and that the securing means. ..

Description

The The invention relates to a gas bag module according to the preamble of the claim 1.

Front airbag modules are common constructed as follows: inflatable by an inflator Airbag is in a housing recorded, which frictionally is connected to a vehicle-mounted component. In the case of a passenger front airbag module, which is the most important application of the present invention, this vehicle-mounted component is often the instrument panel, a component which is rigidly connected to the instrument panel, or a combination thereof. The housing has an outlet opening, through which the gas bag on actuation of the gas generator exits. This outlet is spanned by a door, which Part of a cover is. In the case of a passenger front airbag module can the door one piece formed with the instrument panel and of weakening lines, which form predetermined breaking and hinge areas, be surrounded. The lines of weakness have to very precise be trained to perform their task reliably. However, there is an instrument panel a very large plastic injection molded part is, is the effort that one must operate, so that the lines of weakness educate with sufficient precision, great.

From the generic US 5,588,669 a passenger gas bag module is known in which a separate cover member is provided with a door. The instrument panel has a through hole which is closed by a cover portion of the cover member. In addition to this covering section, the covering element has two fastening sections which are connected in a clamping manner and thus non-positively connected to the instrument panel via latching noses. In order to prevent the cover element from completely detaching from the instrument panel when the gas bag is being expanded, the cover element furthermore has securing means in the form of side walls with apertures. These side walls are latched onto the housing such that projections of the housing protrude into these openings, but do not touch them, so that the cover element floats with respect to the housing (floating cover). However, the protrusions protruding into the openings prevent the cover element from becoming detached during expansion of the gas bag when deformations of the components involved occur due to the high forces. The housing itself is bolted to a carrier below the instrument panel.

adversely There are several aspects to the proposed construction: Zum one can the clamping between cover and instrument panel design condition only with relatively little force done, which in particular to rattling noises to lead can. Furthermore, it is also possible that it is between the side walls of the cover and the projections of the housing for touch and thus to noise developments while the ride comes because the side walls Due to the design, they must have a certain elasticity. Finally, the Construction relatively much space.

In the EP 0 631 907 A1 a passenger gas bag module is described in which the cover is held in a positive and positive manner in the border of a passage opening of the instrument panel. From the cover, a metal bracket extends inwards. This metal strap has a safety hook, which, when the cover is pressed out of the unfolding gas bag from the instrument panel, comes into engagement with an eyelet and thus secures the cover on the instrument panel and in particular limits its opening angle.

The US 5,342,090 proposes, inter alia, to provide at the edge of the passage opening of the instrument panel bevelled contact surfaces on which rests the cover.

For example, from the EP 0 703 122 A1 and the DE 198 56 407 B4 It is known to hold the cover by means of a U-shaped rear handle on the housing.

Of these, Based on the object of the present invention, a generic airbag module to further develop that achieves a more compact design can be.

These The object is achieved by an airbag module having the features of the claim 1 solved.

The Covering element of the gas bag module according to the invention is by means of at least one fastening portion frictionally with connected to a vehicle-fixed component. It is still securing present, which are ineffective at rest, but a detachment of the Prevent cover element during expansion of the gas bag. Act according to the invention this securing means between the cover and the vehicle-mounted component. This leaves while retaining the advantages of the generic concept offers a very compact design. In the present case The compact design has the further advantage of having it through them becomes much easier to prevent unwanted noise.

The at least one fastening means comprises a separate component for constructing the retaining force, which is preferably a screw according to claim 2. This makes it possible to form very high holding forces, which additionally counteracts noise development. Another advantage is that no clip connections are needed, which helps to have very small gaps.

The Holds fastener vehicle-mounted component, cover and housing together. This is possible achieve a very rational assembly. Continue to wear too This measure for noise suppression.

The common attachment of cover and housing on the vehicle-mounted component is achieved in that the housing has a mounting flange and the attachment portion of the cover member the mounting flange at least partially engages under, whereby a clamping fastening supply the attachment portion of the cover between the mounting flange and the vehicle-mounted component takes place.

The Securing means comprise pins which extend from the vehicle-fixed component extend in recesses of the attachment portion of the cover. These pins preferably extend substantially perpendicularly to the surface the door of the Cover. This has the advantage of having no installation in any Complicate way. Another advantage is that no elastic Elements needed become. The components of the securing means are preferably rigid.

Of the Fastening portion of the cover serves both its frictional attachment at rest as well as its backup during expansion of the gas bag.

A preferred application of the gas bag module according to the invention is the use as a passenger front airbag module, wherein the door of the cover a Part of the visible surface the instrument panel forms.

Further preferred embodiments emerge from the dependent claims.

The The invention will now be described with reference to the figures with reference to an embodiment described in more detail. Hereby show:

1 A three-dimensional representation of a housing and a cover member partially pushed onto the housing,

2 a cutaway three-dimensional view of the housing and the cover 1 , which are accommodated in a vehicle-mounted component,

3 the detail D off 2 but in a state during insertion of the housing and cover assembly in the passage opening of the vehicle-fixed component,

4 Housing, cover and vehicle-mounted component in a sectional view, which is parallel to the yz plane, in the region of a Anschraubblockes,

5 this in 4 Shown after tightening the screw and

6 a cut through the in 2 Shown parallel to the yz plane, with the cut passing through a pin.

The embodiment described below is a passenger front airbag module. Such a passenger front airbag module also constitutes an important area of application of the invention. With reference to FIGS 1 . 2 . 4 and 6 First, the basic elements of the gas bag module will be explained. The gas bag module comprises a housing 20 , a cover element 10 and a vehicle-resistant component 30 which is a part of the instrument panel in the embodiment shown. This may be made in one piece with the entire instrument panel, or it may be rigidly connected to this, for example screwed. The vehicle-mounted component 30 - And thus the instrument panel - has a passage opening 32 on, through which one in the housing 20 absorbed gas bag 60 expanded upon actuation of a gas generator also connected to the housing. The housing also shows this 20 an opening, which here as an outlet opening 23 referred to as. To the passage opening 32 and thus also the outlet opening 23 cover in normal operation of the motor vehicle, is the cover 10 with a a door 13a having cover section 12 intended. The cover section 12 that's outside the door 12a still a narrow edge strip 13b has, forms in the fully assembled state of rest of the airbag module part of the visible surface of the instrument panel. When the gas generator is activated and the gas bag is expanded, the door opens 12a along and a predetermined breaking line 18 and works around the hinge 19 on (best to see in 6 ).

The cover element 10 has three sections, namely the cover section just mentioned 12 and two L-brackets serving as attachment portions 14a . 14b , which are parallel to the long sides 12a . 12b of the cover section 12 extend on the underside. These L-hangers 14a . 14b are a part of the fasteners which are non-positive Attachment of the cover 10 on the vehicle-fixed component 30 serve. The cover element 12 is preferably a one-piece plastic injection-molded part.

When mounting the module, the cover element is first 10 on the housing 20 arranged. For this purpose, the housing 20 a mounting flange 24 on, on its long sides 24a . 24b the cover 10 by means of the L-brackets described above 14a . 14b is postponed. The L-hanger 14a . 14b each have a first leg 15a . 15b and a second leg 16a . 16b , After pushing the cover 10 on the case 20 engage under the second thighs 16a , b the mounting flange 24 of the housing 20 as this particular in 3 you can see. Here is the position of the Abdec kelements 10 with respect to the housing neither exactly defined in x, nor in y, nor in the z direction, the cover 10 "Floats" with respect to the housing 20 , Both the second leg 16a of the first L-bracket 14a , as well as the first long side 24a of the mounting flange 24 have recesses in the form of openings. The openings of the first L-bracket 14a be as through holes 17 and the openings of the mounting flange 24 be as bores 25 designated. Since the housing is often a metal component, the holes are 25 often actually drilled, but this is not mandatory. In this respect, the term "bore" in this context is not restrictive to understand the method of production, but as a synonym for breakthrough.

Each in the middle of a page 24a . 24b . 24c . 24d of the mounting flange 24 shows the case 20 a screw-on block 27 on (in 1 are only two of these Anschraubblöcke 27 but the others are arranged accordingly). The screw-on blocks 27 , which are on the long sides 24a . 24b are from the mounting flange 24 spaced so that they slide on the cover 10 not in the way.

In the state when the cover completely on the housing 20 postponed, through holes are aligned 17 and drilling 25 essentially (s. 2 and 3 ). In this state, the cover off 10 and housing 20 existing assembly on the vehicle-fixed component 30 to be ordered. This happens because the said assembly from above into the passage opening 32 is introduced ( 3 ). The border area 34 of the vehicle-mounted component 30 has upper sloping surfaces 36 along, along which the edges 12a . 12b . 12c . 12d of the cover section 12 be guided of the cover. Thus, the position of the visible cover portion 12 of the cover 10 only through the closure section 12 itself and through the edge region of the vehicle-fixed component 30 defined, so that a very high accuracy of fit is achieved.

Below the sloping surfaces 36 is on one side, namely on the side where the hinge is 19 of the cover 10 to lie down, a mounting block 38 from which a series of rigid pins 39 protrude. Here is every pin 39 a through hole 17 and a hole 25 assigned by which the pin protrudes in the assembled state (see in particular 2 ). There, where the Anschraubblock 27 is the attachment block 38 interrupted.

After the cover off 10 and housing 20 existing assembly in the passage opening 32 of the vehicle-mounted component 30 was inserted, penetrate the pins 39 the holes 25 and the through holes 17 but without a fixing function or a positioning function with respect to the cover member 10 exercise. This is achieved by the diameter of the pins 39 smaller than the diameters of the through holes 17 and the holes 25 , The positioning of the cover 10 happens exclusively through the upper inclined surfaces 36 of the edge area 34 of the vehicle-mounted component 30 , so that no tolerance chain is established. In other words: the visible part of the cover 10 namely the cover section 12 , becomes exclusively through the likewise visible part, namely the border area 34 of the vehicle-mounted component 30 positioned. Thus, very small tolerances can be met, resulting in a very small and very uniform gap between cover 12 and vehicle-mounted component 30 results.

For frictional connection of the cover 10 and housing 20 existing assembly with the vehicle-fixed component 30 serve four screws 50 , in each Anschraubblock 27 of the housing 20 a screw 50 is screwed in. In the state in which the cover element 10 and housing 20 existing assembly already in the passage opening 32 of the vehicle-mounted component 30 taken, but not yet screwed with this (see 2 and 4 ), is the cover element 10 floating with respect to the housing 20 held, ie there is no adhesion. This makes it possible that the position of the cover 10 exclusively by the vehicle-mounted component 30 and is not defined by the housing, so that manufacturing tolerances of the housing, not transmitted to a visible from the outside component. Also the pins 39 do not contribute to the positioning of the cover 10 so that there is no risk of static over-determination. This also means that the pins at the Mon days and dormant are inoperative. This also means that their presence does not increase the assembly costs.

After inserting the cover 10 and housing 20 existing assembly in the passage opening 32 of the vehicle-mounted component 30 and the case occurring automatic positioning of the cover 10 , be the four screws 50 tightened, eliminating the long sides 24a . 24b of the mounting flange 24 on the second leg 16a , b the L-hanger 14a , b of the cover 10 be pressed, causing the three components cover 10 , Casing 20 and vehicle-mounted component 30 be positively connected with each other. The traction between the L-bars 14a . 14b and the vehicle-mounted component 30 takes place exclusively in the area of Anschraubblöcke 38 , over protrusions 14c the L-hanger 14a . 14b which on sloping lower contact surfaces 37 of the vehicle-resistant component are pressed (s, see 4 and 5 ). Thus, the position of the cover in the z-direction by direct contact between the vehicle-fixed component 30 and cover 10 defined and is from the housing 20 independently. After tightening the screws, the assembly is complete.

The function of the pins 39 and the through holes 17 is the following: If the gas generator is actuated in an accident, the gas bag exits the housing and, the predetermined breaking line 18 breaks and the door 12a works around the hinge 19 on. Due to the large forces occurring, the housing 20 often deformed, which does not ensure that the clamping between mounting flange 24 , second thigh 16a and vehicle-mounted component 30 preserved. Without the presence of the pins, it could therefore happen that the L-bar 14a from the gap between mounting flange 24 and mounting block 38 slips out, causing the door 12 from the vehicle-fixed component 30 and could fly uncontrollably through the vehicle interior. This is reliably prevented by the pins. A detachment of the cover 10 is excluded because they slipping out of the second leg 16a out of the through mounting flange and mounting block 38 prevent gap formed even without the presence of clamping forces.

The first L-shaped bracket 14a thus has a double function. It serves both the non-positive attachment of the cover 10 on the vehicle-fixed component, namely by clamping through the mounting flange of the housing, as well - together with the pins 39 - The fuse of the cover at ignition of the gas generator. So he is both a part of the fastener as well as a part of the securing means.

in the shown embodiment is there a break line and a hinge with associated pins, which the open door before a detachment from secure the internal structure of the motor vehicle. It would be too possible, to have two hinges and a break line, which are in a middle section of the door extends, such that the door two wings having. In this case, it is preferable for each hinge securing means provided.

10

cover

12

cover

12a, 12b

long side

12c, 12d

short page

13a

door

13b

edge strips

13c

head Start

14a, 14b

L-bracket

15a, 15b

first leg

16a, 16b

second leg

17

Through Hole

18

Line of weakness

19

hinge

20

casing

22

reception area

23

outlet opening

24

mounting flange

25

drilling

27

Anschraubblock

30

fixed to the vehicle component

32

Through opening

34

border area

36

upper inclined surfaces

37

lower inclined surfaces

38

mounting block

39

Pin code

50

screw

60

airbag

Claims (12)

Airbag module with an outlet opening ( 23 ) housing ( 20 ) into which an airbag ( 60 ), a passage opening ( 32 ) vehicle-mounted component ( 30 ), a cover element ( 10 ) with at least one attachment section and one door ( 13a ) having cover section ( 12 ), which the passage opening ( 32 ) and at least a part of the outlet opening ( 23 ), wherein the attachment portion frictionally with the vehicle-fixed component ( 30 ), and securing means, which are ineffective in the idle state of the gas bag module, a detachment of the cover ( 10 ) of the vehicle-mounted component ( 30 ) during expansion of the gas bag ( 60 ), characterized in that the securing means are located directly between the cover element ( 10 ) and the vehicle solid component ( 30 ) act that fastening means for the cover next to the attachment portion comprise at least a separate component, due to its cover ( 10 ), Casing ( 20 ) and vehicle-mounted component ( 30 ) are positively connected to each other, wherein the cover ( 10 ) has a mounting portion which has a mounting flange ( 24 ) of the housing ( 20 ) and that the securing means pins ( 39 ) extending from the vehicle-mounted component ( 30 ) in the direction of the cover element ( 10 ), and recesses (through holes 17 ) in the cover element ( 10 ) into which the pins ( 39 ) protrude. The gas bag module according to claim 1, characterized in that the separate component is a screw ( 50 ). Airbag module according to one of the preceding claims, characterized in that the diameter of the recesses greater than the diameter of the pins ( 39 ). The gas bag module according to claim 3, characterized in that the recesses pass through holes ( 17 ) and that the mounting flange ( 24 ) further recesses (bores 25 ), so that the pins ( 39 ) through the mounting portion in the mounting flange ( 24 ). Airbag module according to claim 4, characterized in that that the diameter of the other recesses in the mounting flange of the housing greater than the diameters of the pins are. Airbag module according to one of the preceding claims, characterized in that the pins ( 39 ) substantially perpendicular to the cover portion ( 12 ). Airbag module according to one of the preceding claims, characterized characterized in that the fastening means both for attachment the cover as well as for attachment of the housing serve the instrument panel. Airbag module according to one of the preceding claims, characterized in that the vehicle-mounted component is rigidly connected to the instrument panel or the instrument panel itself is. Airbag module according to one of the preceding claims, characterized in that the edge region of the vehicle-fixed component ( 30 ) upper inclined surfaces ( 36 ) having the position of the cover ( 10 ) define. Airbag module according to one of the preceding claims, characterized in that the vehicle-mounted component ( 30 ) further lower sloping surfaces ( 37 ), via which adhesion between the cover and the vehicle-mounted component takes place. The gas bag module according to claim 10, characterized in that the cover element protrusions ( 14c ), over which the adhesion occurs. Airbag module according to one of the preceding claims, characterized in that the securing means a hinge ( 19 ) assigned.