Bridge igniter
AssigneeRobert Bosch GmbH
InventorsRoland Mueller-Fiedler, Winfried Bernhard, Ulrich Kunz
Life of this patent
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Abstract
The present invention relates to a bridge igniter 1 having: a resistance layer 3 which has a given electrical resistance and which can be heated by an electrical current; an electrical insulating layer 4 that is disposed on the resistance layer 3 and has a given thermal conductivity; a reactive layer that is disposed on the insulating layer, the insulating layer 4 transmitting the heat that is produced in the resistance layer 3 to the reactive layer 5, thereby causing the latter to undergo an exothermic reaction; and a pyrotechnic layer 7 that is disposed on or above the reactive layer 5 and that may be set off by the exothermic reaction of the reactive layer 5.
Claims16
A bridge igniter (1) comprising:
- a resistance layer (3) having a given electrical resistance which can be heated by an electrical current;
- an electrical insulating layer (4) that is disposed on the resistance layer (3) and has a given thermal conductivity;
- a reactive layer (5) that is disposed on the insulating layer, the insulating layer (4) transmitting the heat generated in the resistance layer (3) to the reactive layer (5), thereby causing the latter to undergo an exothermic reaction;
- and
- a pyrotechnic layer (7) that is disposed on or above the reactive layer (5) and may be initiated by the exothermic reaction of the reactive layer (5).
The bridge igniter as recited in one of the preceding claims, wherein the resistance layer (3) is formed in particular of palladium or nickel-chromium.
The bridge igniter as recited in one of the preceding claims, wherein the reactive layer (5) is formed in particular of zirconium or hafnium.
The bridge igniter as recited in one of the preceding claims, wherein an adhesive layer (9), such as a titanium layer, is disposed on and/or under the resistance layer (3).
The bridge igniter as recited in one of the preceding claims, wherein the insulating layer (4) functions as an adhesive layer (9) between the resistance layer (3) and the reactive layer (5).
The bridge igniter as recited in one of the preceding claims, wherein a co-reactant (6) cooperates with the reactive layer (5) to produce an exothermic reaction in the latter.
The bridge igniter as recited in one of the preceding claims, wherein a co-reactant (6), especially an oxide layer, is disposed on the reactive layer (5).
The bridge igniter as recited in one of the preceding claims, wherein the insulating layer (4) functions as a diffusion barrier between the resistance layer (3) and the reactive layer (5).
The bridge igniter as recited in one of the preceding claims, wherein electrical contact surfaces (10), gold plates for example, are connected to the resistance layer (3) in order to provide it with electrical power.
The bridge igniter as recited in one of the preceding claims, wherein the bridge igniter (1) is disposed on a substrate (2), for example, a silicon or silicon dioxide substrate, a ceramic, a plastic or an integrated circuit.
A process as recited in one of the preceding claims, wherein the resistance layer (3) is configured in a bridge shape.
Dependencies are inferred from the claim text.