WO2004094190A2

WO2004094190A2 - Airbag deployment sensor tape folding loom

Info

Publication number: WO2004094190A2
Application number: PCT/US2004/003870
Authority: WO
Inventors: Edward R. Stembler
Original assignee: Key Safety Systems, Inc.
Priority date: 2003-04-22
Filing date: 2004-02-09
Publication date: 2004-11-04
Also published as: US20040211795A1; WO2004094190A3

Abstract

A tape (42) for use within an airbag deployment sensor is formed in an apparatus (20) having a housing (22) that receives an elongated tape (42) within a tape slot (36). A pin base (60) with upwardly protruding parallel pins (56) is positioned forward of the tape slot and reciprocates vertically. A tray (38) is mounted to the housing forward of the pins (56) which has an upwardly facing support surface (40) that receives the elongated tape (42) thereon as it is folded. Parallel blades (54) are mounted to the housing and are slidable in the front to back direction. Each blade (54) is movable from behind the pins (56) to extend between two pins such that portions of the blade protrude forward of the pins (56). Each blade may thus extend across the tray support surface (40) to engage with the tape (42) extending through the tape slot (36) to impose a fold (50) on the tape.

Description

AIRBAG DEPLOYMENT SENSOR TAPE FOLDING LOOM

The present invention relates to an apparatus for fabricating a fan folded tape used in an airbag deployment sensor to determine the progress of airbag deployment.

A crash event triggers an airbag deployment algorithm that determines whether deployment of the airbag will be conducive to a positive outcome for the vehicle occupant. These automated decisions are made in a very short period of time, and may be subject to revision in light of the additional data that is provided during a crash and the milliseconds immediately following impact. It is important to determine if the airbag is impacting a vehicle occupant before the airbag is fully deployed. If the vehicle occupant engages the airbag too soon it is preferable to instantly deflate the airbag rather than continue to inflate it. Thus sensors are required to determine when the vehicle occupant engages the airbag, or, more particularly, when the deployment of the airbag is restricted by encountering a vehicle occupant.

A sensor taught in EP 0990567A1 employs a plurality of tapes that extend between the front of the airbag and a tape dispensing cartridge mounted on the airbag housing. Tape extraction sensors within the cartridge monitor the rate at which tape is withdrawn from the cartridge and thus can detect airbag impact with a vehicle occupant by a decrease in airbag velocity. One compact mechanism for storing the tape within the cartridge before deployment is to fold the tape into a series of fan folds. Such a tape storage approach is very volume effective and does not require rotating parts. Withdrawal of the fan folded tape does not build up momentum like a spool of tape can.

What is needed is an apparatus for rapidly and repeatedly forming the required pleats in the airbag deployment sensor tapes.

There is provided by the present invention an airbag deployment sensor tape folding loom used for fabricating an airbag deployment sensor tape. The loom comprises an apparatus having a housing that receives an elongated and unfolded tape within a tape slot. The tape extends from a housing inlet to a housing outlet. A pin base is mounted to the housing for reciprocating vertical motion, and is positioned forward of the tape slot. Parallel pins extend upwardly from the pin base. A tray is mounted to the housing forward of the pins which has an upwardly facing support surface that receives the elongated tape thereon as it is folded. Parallel sliding blades are mounted to the housing and are slidable in a front to back direction. Each blade is movable between a first position rearward of the pins to a second position extending between two pins such that portions of the blade protrude forward of the pins. Each blade in the second position extends across the tray support surface, and the blades are thus engageable with the tape extending through the tape slot to impose a plurality of folds on the tape.

Features and advantages of the invention will be apparent from the following detailed description when taken in conjunction with the accompanying drawings.

FIG. 1 is an exploded isometric view, partially broken away in section, of the airbag sensor tape loom of this invention, shown with a partially folded tape.

FIG. 2 is a top plan view of the tape loom of FIG. 1 , with the cover partially broken away in section, to show the tape in the process of being folded.

Referring to FIGS. 1-2, wherein like numbers refer to similar parts, the tape folding apparatus 20 is shown. The apparatus 20 has a housing 22 that may be formed of plastic, metal or another suitable material. The housing 22 is generally box-like and has a base wall 24 with an upwardly extending front wall 26, a left sidewall 28, and a right sidewall 30. A notch is formed along the upper edge of the left sidewall 28 that defines a tape inlet 32. A similar notch is formed along the upper edge of the right sidewall 30 that defines a tape outlet 34. A tape slot 36 extends between the inlet 32 and the outlet 34.

A sliding tray 38 is located within the housing 22 forward of the tape slot 36. The sliding tray 38 has an upwardly facing horizontal tape support surface 40 onto which an elongated tape 42 extends during the folding operation. A tape compartment 31 is defined within the walls 26, 28, 30, forward of the tape slot 36 and above the sliding tray 38. The tray 38 extends between a tray slot 44 in the left sidewall 28 and a tray slot, not shown, in the right sidewall 30. An upper flange 46 extends upwardly from the surface 40 of the tray 38. The upper flange 46 is substantially parallel to the left sidewall 28, and is positioned adjacent the inside of the right sidewall 30 at the beginning of the processing of a tape 42, and serves to compress a folded tape when the tray 38 is slid toward the left sidewall 28, as described more fully below. The sliding tray 38 is slightly more than twice as wide as the housing 22 and has an outside segment 48 that protrudes to the right of the flange 46 and extends exterior to the housing at the beginning of the folding process.

For purposes of storage within a sensor device, the tape 42 should be compactly formed with a series of fan folds 50. In FIG. 1 , the tape 42 may be preprinted or otherwise treated to have a series of alternating dark and light stripes 52. The fan folds 50 are imposed on the tape 42 by the interaction between a series of sliding blades 54 and vertically extending pins 56.

The pins 56, which may be formed of metal or other rigid material, extend upwardly from a pin base 60 which extends from side to side rearward of and beneath the sliding tray 38. The pin base 60 is arranged for reciprocating vertical movement within the housing 22. Various mechanisms may be employed, for example, horizontal rods 62 may extend outwardly from the ends of the pin base 60 to ride within vertical slots 64 formed in the housing sidewalls 28, 30. The pins 56 are parallel to one another and equally spaced apart. The pins 56 extend above the level of the sliding tray 38 support surface 40, preferably to at least the height of the tape 42 which is being processed.

The blades 54 run from front to back within the housing, and extend within parallel blade slots 68 formed in the housing 22 rearward of the pins 56. The blade slots 68 have floors, not shown, which support each blade 54 at a level to allow it to slide freely across the tray support surface 40. The blades 54 are retained within the blade slots 68 and are prevented from tipping by a restraint plate 70 that is fastened to the housing 22 to overlie the blade slots 68 and the blades 54 retained therein.

Each blade 54 extends perpendicular to the tape slot 36 and is centered to project out over the sliding tray support surface 40 at a position between two pins 56. In FIG. 2, each blade 54 may be independently operated to cross the tape slot 68, engage a tape 42, and extend the tape in a fan fold across the sliding tray 38. The blades 54 are operated one after the other, starting from the inlet end of the housing, to add additional fan folds to the tape 42 until the sliding tray 38 is filled with folded sections of tape. As the blades 54 are operated they draw additional tape 42 from the direction of the on folded portion of the tape into the apparatus 20. The housing 22 has a transparent cover 72 which is hinged to the front wall 26 and which is closed over the sliding tray 38 during operation. The cover 72 terminates at a short distance from the restraint plate 70 so that the tape slot 36 is not obstructed by the cover.

To remove a folded tape 42 from the apparatus 20, the blades 54 are withdrawn between the pins 56. To facilitate the uniform withdrawal of the blades 54, each blade is preferably provided with an outer notch 74. The notches 74 of all the depressed blades 54 may be simultaneously engaged by a retraction member 76, as shown in FIG. 1. The retraction member 76 has downwardly opening slots 78 to correspond with each notch 74.

After the blades 54 are withdrawn, the rods 62 are depressed to lower the pin base 60 and the pins 56 below the level of the sliding tray support surface 40. The pin base 60 may be held by friction or the operator in either a depressed condition or in a raised position. The outside segment 48 of the sliding tray 38 is then pressed to urge the flange 46 against the folds of the tape and to compress the fan folds 50 into a compact arrangement. The folds will be restrained between the left sidewall 28 and the flange 46.

Once the folds have been compressed, a user may, flip open the cover 72 about its hinges 80, grasp the completed folded tape and remove it from the apparatus 20. To facilitate engagement of the folded tape by the user's fingers, a finger relief opening 81 is defined in the left sidewall 28 forward of the tape inlet 32, and a similar finger relief opening finger relief is formed along the upper edge of the sliding tray flange 46.

Although the apparatus 20 has been shown as a manually operated fixture, it may readily be automated utilizing closing cams and stepper type motors to operate the blades, the retraction of the pins, and the insertion of the raw tape.

The operation of the apparatus 20 is as follows. First, with the sliding tray 38 fully extended to the right, the cover 72 is opened. Next, the pins are returned to the up position. A fresh, unfolded, tape 42, approximately 91.5 centimeters long, is then threaded through the tape slot 36, leaving approximately 2.5 centimeters of tape extending outwardly of the inlet 32. The remainder of the tape 42 will extend through the tape slot and protrude through the outlet 34. The cover is then closed, and the 2.5 centimeters of tape extending from the tape inlet 32 is held against the left sidewall 28. The blade 54 closest to the left sidewall 28 is slid into the housing, and then the remainder of the blades are advanced, while holding the earlier depressed blades in their depressed position. Once all the fan folds have been imposed on the tape, the retraction member 76 is used to move the blades to the open position. Once opened, the blades may be moved slightly forward to reposition the tape folds against the pins. The blades may then be retracted again. The pins are then moved to the full down position. The tray is slid to the left, thereby closing and compressing the tape folds. The cover is then opened, and the folded tape removed. If necessary, the tray may be moved slightly to the right to facilitate removal.

Claims

CLAIMS:

1. An apparatus (20) for folding elongated tapes (42), the apparatus comprising: a tape supporting tray (38); a housing (22) having portions defining an interior tape compartment (31 ), into which the tray (38) extends; portions of the housing (22) defining a tape slot (36) communicating with the tape compartment (31 ) and having an inlet (32) and an outlet (34); a plurality of pins (56) that project upwardly into the tape compartment (31 ), the pins (56) being movable to be positioned below the tray (38), the pins (56) being positioned forward of the tape slot (36) and rearwardly of the tray; portions of the housing (22) which define a plurality of parallel blade slots (68) communicating with the tape compartment (31 ); and a plurality of blades (54), each blade being mounted in one of said blade slots (68), wherein each blade is movable from a first position rearward of the pins (56), and a second position extending between two pins such that portions of said blade protrude forward of the pins (56) wherein each blade in the second position extends across the tray support surface (40), the blades (54) being engageable with a tape (42) extending through the tape slot (36) to impose a plurality of folds on the tape (42).

2. The apparatus (20) of claim 1 wherein the housing (22) has a first wall (28) which extends upwardly above the level of the tray support surface (40), and wherein a flange (46) extends upwardly from the tray (38) within the housing (22), the flange (46) being substantially parallel to the housing first wall (28), such that the tray may be advanced to compress the folded tape (42) between the flange (46) and the first wall (28).

3. The apparatus (20) of claim 1 or 2 wherein the flange (46) has portions defining an upwardly opening finger relief opening (82), and the first wall (28) has portions defining an upwardly opening finger relief opening (81 ).

4. The apparatus (20) of any of claims 1 - 3 further comprising a cover which is hinged to the housing (22) and which in a first position extends over and covers the tape compartment (31 ), and in a second position allows access to the tape compartment.

5. The apparatus (20) of any of claims 1 - 4 wherein the housing (22) has a first sidewall (28) and a parallel second sidewall (30), and wherein parallel tray slots are defined in the first sidewall (28) and the second sidewall (30) to receive the tray (38) extending therethrough, and wherein portions of the tray extend outwardly from the second sidewall (30) prior to the imposition of the plurality of folds on the tape (42).