Inertial switch
![]() A disconnect switch | |
Type | Switch |
---|---|
Electronic symbol | |
![]() |
An inertial switch is a switch, firmly mounted upon a vehicle or other mobile device, that triggers in the event of shock or vibration. It is a part of electrical circuits that may either enable or disable some function.[1]
Disconnect
The switch shown to the right is intended to disable an electric fuel pump in automotive applications. This functionality is required in some vehicle racing applications, since an electric fuel pump may otherwise continue operating after a collision or rollover. If the fuel line is broken or the vehicle is inverted, fuel may be spilled, creating a fire hazard. A small loose weight (called a proof mass) is trapped within a spring-loaded cage. A shock in any direction will cause movement of the mass relative to the cage. If sufficiently shocked, the cage will spring open which actuates an associated switch. The switch is reset by pressing the cage closed through the flexible (red) top cover, retrapping the mass. These switches are also used to open a contactor (a large relay) to disable the high power circuit of a battery electric vehicle upon collision.
Actuation
A normally open switch is used to activate passenger safety equipment early in a collision, typically to pre-tension seat belts and/or to activate airbags to protect the occupant(s) from collision with the vehicle interior or the steering wheel.
Inertia switches are also used in ordnance applications for both safety (shell will not explode until it has been subjected to launch acceleration) and fuzing.
References
- v
- t
- e
- Analogue switch
- Banyan switch
- Battery isolator
- Cam switch
- Centrifugal switch
- Company switch
- Contact protection
- Crossbar switch
- Crossover switch
- Cryotron
- DIP switch
- Dry contact
- Electric switchboard
- Float switch
- Half-moon switch
- Humidistat
- Infinite switch
- Inertial switch
- Kill switch
- Key switch
- Knife switch
- Limit switch
- Latching switch
- Light switch
- Lightning switch
- Magnetic proximity fuze
- Magnetic starter
- Magnetic switch
- Mercury switch
- Miniature snap-action switch
- Motion-triggered contact insufficiency
- Nintendo Switch
- Optical switch
- Photoswitch
- Piezo switch
- Placebo button
- Pull switch
- Push switch
- Push-button
- Railroad switch
- Reed switch
- Rotary switch
- Sail switch
- Sea switch
- Sense switch
- Silicone rubber keypad
- Softswitch
- Spark gap
- Staircase timer
- Stepping switch
- Strowger switch
- Thermostat
- Time switch
- Touch switch
- Transfer switch
- Vacuum switch
- Vandal-resistant switch
- Wireless light switch
- Zero speed switch
![Switches](http://upload.wikimedia.org/wikipedia/commons/thumb/4/46/SPST-Switch.svg/80px-SPST-Switch.svg.png)
This article about an automotive part or component is a stub. You can help Wikipedia by expanding it. |
- v
- t
- e