Patent ID: 8251415

Claim:
An end effector for a robot for retrieving work products and placing the retrieved work products at a delivery site, said end effector comprising: a vacuum plenum housing, an array of vacuum retrievers extending down from said vacuum plenum housing for engaging the work products, a valve positioned in each said vacuum retrievers that separates each said vacuum retrievers into an upper chamber in communication with said vacuum plenum housing and a lower chamber in communication with the atmosphere for engaging the work products, said valves each defining an air passage between said upper chamber and said lower chamber for the movement of air from the lower chamber to the upper chamber and into said vacuum plenum, and a valve element comprising a diaphragm movable in said upper chamber into and out of blocking relationship with said air passage, wherein said upper chamber of said vacuum retrievers are configured to be moveable in response to closing of said air passage and a reduced air pressure drawn in said upper chamber.