Reed switches in Seatbelt lock sensing
Seat belts are vehicle safety device used to secure the occupants of a vehicle against harmful movement that may result during a collision or a sudden stop. They also ensure that the occupants are secured in the right place, for airbags to be more effective when deployed. The first step automobile manufacturers look at is to check whether a passenger is seated at a particular location, and then check if the seat belts have be secured. For this, a reed switch and a magnet under the seat is used, and when a passenger is seated, the magnet moves closer to the reed switch and signals the microprocessor. This ensures that the seat belt warnings are issued only where passengers are seated. The next step is to check whether the passenger has actually secured the seat belts so the alarm can be disabled. Vane sensors, which consist of a reed switch and magnet secured at a fixed distance to keep them actuated, are fitted inside the seatbelt holster. When the seat belt lock is inserted, and it comes between the reed switch and the magnet, the magnet’s field is shunted away and the reed switch opens.
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.
Magnet Biasing Type
 | Magnet Biasing type Vane application Some special field applications, for the sake of circuit logic, security concerns, or a power Continue reading Nov 30, 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.
MS-324 Miniature Flat Pack Reed Sensor with Actuator
 | Drawing of MS-324 Magnet Sensor starFeatures10W Contact Rating. Normally Open contact. Three sensitivity bands. Sputtered Ruthenium Continue reading Oct 30, 2020 |
MM-1018 Micro Miniature Reed Switch
 | This 10.0 mm long, Form A type Micro Miniature reed switch is designed for moderate power, low load applications. The fast operate Continue reading Jun 2, 2021 |
MS-106 Reduced Miniature PCB Mountable Reed Sensor
 | Drawing of MS-106 Reed SensorDrawing of MS-106 Reed Sensor Pad Layout starFeatures10W Contact Rating. 15.2 mm PCB Pitch. Normally Continue reading Dec 2, 2020 |
MS-214 Miniature Cylindrical Sensor
 | Drawing of MS-214 Magnet Sensor starFeatures10W Contact Rating. Normally Open contact. Three sensitivity bands. Sputtered Ruthenium Continue reading Oct 30, 2020 |