Is there a pressure-sensing ylinder, such that If an arm gets caught in a device returning, it'll stop? Thanks

Question

Hi, I am looking for something that I'm not sure exists or not, and I need your help.

On some automobiles, like VW for example, they have a safety feature such that if you stick your hand in the window and glass is rolling up, when the glass catches your hand, it will sense that and roll down automatically.

Now, my question is, do you happen to have a cylinder (pneumatic preferred) that has such sensing ability? For example, If I have a device that's returning and catches an operator's arm, it will sense the arm (by pressure maybe?) and stop moving?

I know I could put some sensors on and program the machine to do this in a time-based way, but I really would prefer a pressure-based sensing. Please let me know if there is such pressure-sensing cylinder or not, that'd help me a lot. Thank you very much for your help.

Answer 1

Such a thing exists!

Answer 2

you can get a load cell that would send a signal to the cylinder controller...

the electric motors have a current trip circuit (if it uses too much current due to resistance, it stops)

Answer 3

Instead of a pressure switch you might try just using an electrical plunger type shut off switch which we use on all of our automotive lifts.

Hope that this helps and good luck.