Safety Air Switch Logic for Clamps

Advice on sources for pneumatic clamps that require two-handed actuation for safety. August 30, 2010

I need to learn something about air switch logic. I am trying to develop some air actuated clamps but I want to ensure that both hands are safely out of harmís way when the clamp is being actuated. I also need to be able to leave the project in clamped position without having to keep any switches depressed by clamping. Specifically I would like to require that your left hand engage air into the system and your right hand actuate the clamp. After clamp is actuated somehow the left side still receives necessary air to drive the clamp. Does anybody here know enough about air logic to know if this is possible?

Forum Responses
From contributor O:
It is possible but I do not know the mechanics of how it works. Our Maka mortiser and Gartop finger joint press work like this. The press has no electricity to it so it is a function of the air switches.

From the original questioner:
I want to make sure I am clear here.

You say you can:
Engage air with left hand.
Engage clamp with right hand.
Clamp will not activate unless air switch is depressed at left.
Clamp will continue to clamp after both hands are removed from both switches.

From contributor O:
No pushing of left or right to activate the clamps. They both have to be pushed to get things going. The buttons on the Arch press can be released right away but on the Maka you have to hold them for the entire drill or mortise sequence. Both machines are set up for safety but I am sure with the right pneumatic switches you can accomplish what you want.

The Maka has an additional foot pedal that clamps the work piece at low pressure (will not smash your fingers) while you get set to push the two buttons. Something else to think about for safety is the new type pneumatic clamps with a wide head and short 10mm throw. Itís hard to get fingers under these.