Airbag and a deployment sensor
First Claim
1. An airbag and a deployment sensor comprising:
- an airbag cushion, defining a cushion interior having an inside surface;
a structure to which the airbag cushion is attached;
a sensor mounted to the structure, and mounted internal to the airbag cushion, the sensor further comprising;
a cartridge having portions defining a storage space within the cartridge, the storage space containing a quantity of string, the cartridge having portions forming a string outlet, wherein one end of the string is attached to a portion of the inside surface of the airbag cushion, so that deployment of the airbag cushion draws string out of the storage space in the cartridge, through the string outlet, and the string leaving the string outlet defines a direction of string withdrawal;
a structure positioned within the cartridge to cause string drawn out of the storage space to move transverse to the direction of string withdrawal, wherein the transverse motion caused has a periodicity which is proportional to the length of string withdrawn;
at least one string sensor positioned in the cartridge between the storage space and the string outlet, the at least one string sensor positioned to detect the transverse motion of the string, so that the sensor output varies with a frequency proportional to the rate string is withdrawn from the cartridge.
3 Assignments
0 Petitions
Accused Products
Abstract
A cartridge stores a quantity of string, one end of which is attached to the inside surface of an airbag cushion. A spool which transitions to a cone is situated within the cartridge. A narrow gap around the spool forms a string storage space and a similar gap overlies the cone and leads to an outlet. Positioned within the body of the cartridge is a light source and a light detector. As string is drawn out of the cartridge, the string traverses between the light sources and a light detector generating a signal directly proportional to the rate at which string is withdrawn. The geometry of the cartridge is arranged to provide friction against the string. The friction is created between the string and the junction between the cylindrical spool and the cone and rapidly overcomes the momentum of the string when the airbag cushion comes to a stop.
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Citations
33 Claims
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1. An airbag and a deployment sensor comprising:
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an airbag cushion, defining a cushion interior having an inside surface;
a structure to which the airbag cushion is attached;
a sensor mounted to the structure, and mounted internal to the airbag cushion, the sensor further comprising;
a cartridge having portions defining a storage space within the cartridge, the storage space containing a quantity of string, the cartridge having portions forming a string outlet, wherein one end of the string is attached to a portion of the inside surface of the airbag cushion, so that deployment of the airbag cushion draws string out of the storage space in the cartridge, through the string outlet, and the string leaving the string outlet defines a direction of string withdrawal;
a structure positioned within the cartridge to cause string drawn out of the storage space to move transverse to the direction of string withdrawal, wherein the transverse motion caused has a periodicity which is proportional to the length of string withdrawn;
at least one string sensor positioned in the cartridge between the storage space and the string outlet, the at least one string sensor positioned to detect the transverse motion of the string, so that the sensor output varies with a frequency proportional to the rate string is withdrawn from the cartridge. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. An airbag cushion deployment sensor comprising:
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a cartridge having portions which define a storage space within the cartridge, the storage space containing a quantity of string, arranged in coils stacked one upon another, the cartridge having portions forming a string outlet positioned above the storage space so that when the string is withdrawn from the string outlet, string is removed from the string storage space by unwinding one coil at a time so that the string moves transverse to a direction defined by string withdrawal, wherein the transverse motion caused has a periodicity which is proportional to the length of string withdrawn; and
at least one string sensor positioned in the cartridge between the storage space and the string outlet, the at least one string sensor positioned to detect the transverse movement of the string, so that the sensor output varies with a frequency proportional to the rate string is withdrawn from the cartridge. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20, 21)
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22. An airbag cushion deployment sensor comprising:
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a cartridge having portions defining an interior storage space;
portions of the cartridge which define a string outlet communicating with the interior storage space;
a spool fixed within the cartridge interior storage space;
a string stored in a coil encircling the spool, and having a first end which extends through the string outlet for connection to the airbag cushion;
at least one light source mounted to the cartridge; and
at least one light detector mounted to receive light from the at least one light source, the at least one light detector being positioned such that extraction of the string from the coil causes the string to only intermittently pass between the at least one light detector and the at least one light source and to thus generate a fluctuating signal corresponding to the speed of withdrawal of the string from the cartridge. - View Dependent Claims (23, 24, 25, 26, 27, 28, 29, 30, 31)
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32. A method of monitoring airbag deployment comprising the steps of:
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deploying an airbag cushion having a string mounted to an interior surface of the airbag, wherein the string is drawn from a cartridge which does not move in response to the deploying airbag cushion;
drawing the string from the cartridge, wherein portions of the cartridge are arranged to cause the string passing through the cartridge to perform an oscillating motion at a frequency proportional to the rate at which the string is being withdrawn; and
detecting the frequency of the oscillating motion and determining the rate at which string is being withdrawn. - View Dependent Claims (33)
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Specification