A metal grill that open and close via force

[remembrance1]

Hi,

I'm looking for a metal grill, that closes it's flaps when I step on a button, and opens the flaps when I release my foot. May I know where can I find such a design?

 

[hacksaw]

Do a search on dampers, they come in all forms and strength of design.

 

[dbill74]

Use a motorized damper connected to a push-button switch.

 

[bimr]

These are used on standby generator applications.

http://www.greenheck.com/media/pdf/catalogs/BackdraftDampers_catalog.pdf