Patent ID: 7698017

Claim:
An electric press having a ram that is movable relative to a work to be processed and having an area sensor connected thereto for detecting a person entering a predetermined area in connection with the electric press, said electric press comprising: detecting means for detecting a predetermined condition of the electric press; signal producing means that is structured and arranged to produce a signal to invalidate said area sensor whenever the detecting means detects that said electric press is in the predetermined condition; and watching means for determining whether or not watching said signal producing means if said signal producing means is operating correctly; wherein said detecting means includes a first detecting means and a second detecting means; said signal producing means includes a first signal producing means and a second signal producing means; said watching means includes a first watching means for watching if said first signal producing means is normally operating and a second watching means for watching if said second signal producing means is normally operating, said first and second signal producing means being prevented from producing the signal for invalidating the area sensor in case one of said first and second signal producing means is not normally operating.