Patent ID: 6510688
Filing Date: 2003-01-28
Classification: F16P,H01L,Y10S

Abstract:
A semiconductor transport container loading and unloading station safety device comprising:a cylinder; a pneumatically operated piston operating by linear movement in said cylinder, the piston being connected to a semiconductor transport container support for moving a semiconductor transport container past a stationary part of a loading and unloading station in at least one direction; devices operably connected to ends of the cylinder for measuring the pressure of air flowing out of the cylinder in a movement direction of the piston, so that a drop in an otherwise substantially constant pressure below a threshold value serves as a switching signal; end stops adapted to stop motion of the support at the end of the motion of the support; end position sensors for sensing end positions before the support reaches the end stops; a controller adapted to reverse or stop motion of the support upon receipt of the switching signal, the controller further adapted to ignore the switching signal when the end position is sensed; and at least one additional device for measuring pressure.