Reed switches as Impact sensors for triggering airbags

Statistics say almost 80% of automobiles use reed switch based crash sensors for triggering airbags. A ring magnet is mounted on a very precise tension spring and this assembly is slid over a reed switch. Depending on the impact which is required to trigger the reed switch, different tension springs are used. In most crash sensors, two reed switches are used instead of one as a failsafe mechanism. When a crash occurs, the mass of the magnet compresses the spring and moves closer to the reed switch, closing it. This signal is used to trigger the compressed cylinder which inflates the airbags.
Application Classification
Applications are classified as Position Sensing, Pulse Counting, Electromagnetic or Relay, Temperature Sensing or Magnet Biasing types. This application is classified as follows and the link gives more information on best practices to help select the most suitable AT band and matching magnet.
Position sensing Type
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Position Sensing type application When an application requires the end position of a movement sensed, or the sensing of a part when it
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Nov 7, 2020 |
Recommended Products
The Reed Switches and Sensors used in such applications need to be robust, durable and efficient in meeting a high life expectancy. Our engineers work hard in life testing our products under various conditions, and our intention is to ensure end product durability and life. Although we wouldn’t want to restrict any of our products for use in only certain applications, the recommended products for use in this application are listed below.
R3 Miniature SMD Reed Sensor
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These miniature SMD reed sensors are designed for low power, high speed switching applications, and have a cost advantage over the
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Jun 7, 2021 |
R2 Standard size SMD Reed Sensor
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R2-S Gull-wing SMD Formed Reed SensorR2-S Gull-wing SMD Formed Reed Sensor Pad LayoutR2-F Low Profile SMD Formed Reed SensorR2-F Low
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Dec 2, 2020 |
MM-1018 Micro Miniature Reed Switch
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This 10.0 mm long, Form A type Micro Miniature reed switch is designed for moderate power, low load applications. The fast operate
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Nov 8, 2022 |
RM-1318 Reduced Miniature Reed Switch
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The RM-1318 Reduced Miniature reed switches are designed for applications where a size restriction is present, but a higher Contact
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Nov 8, 2022 |