Inertia / Acceleration cut-off switch 1

[murpia]

Hi,

Does anyone know of a suitable cut-off switch that can be used to detect a serious impact and cut off a hydraulic system?

The ideal switch would be normally closed and latching open in the event of an impact. It would power a normally-open solenoid valve connected to the hydraulic accumulator. In the event of an impact the switch would latch open, de-powering the valve and releasing the hydraulic accumulator pressure. The valve requires 1.5A.

We would like to use something around the 10->15g range to avoid any false triggering. I think this is above the range of the standard fuel-pump cut-off switches.

Many thanks, Ian

 

[MacGyverS2000]

Ever heard of an airbag?

Dan - Owner

http://www.Hi-TecDesigns.com

 

[MikeHalloran]

There is an inertia cutoff switch on many recent cars.
It's not part of the airbag system; it cuts off the fuel pump in the even of a collision.
It may be adaptable to what you want.

On many recent Fords, it's hidden behind the side panel of the front passenger footwell, and accessible for reset by a finger through a cutout near the top of the panel. That's how you find one in a junkyard...






Mike Halloran
Pembroke Pines, FL, USA

 

[murpia]

Mike,

Are the 'g' specs of that type of switch available anywhere?

I'm interested if it senses in any particular preferred direction, and at what level.

Thanks, Ian

 

[DRWeig]

Natural gas valves feeding buildings are available with inertial slam-shut closers. They used to call them "California Valves" because that's where it all started and they're required by codes there.

Not sure if it could be adapted to hydraulic pressures, but if so would be more fail-safe / no electricity involved.

Probably cost lots more than MikeHalloran's suggestion though. Good one, Mike.

Good on ya,

Goober Dave

 

[FeX32]

Find one and test it yourself .


Fe

 

[thruthefence]

Does it only have to register the g load in one direction?