Patent ID: 7928330

Claim:
A safety switch assembly comprising: a housing; an opening formed in the housing; a key having a first portion and a second portion that is offset from the first portion, the first portion of the key cooperating with the opening formed in the housing altering an operating condition of a control system of a machine; a lock constructed to directly engage the second portion of the key, the key cooperating with the opening to be movable between a fully engaged position wherein the control system allows operation of the machine and the lock is directly engaged with the key, a partially engaged position wherein the control system suspends operation of the machine and the lock remains directly engaged with the key thereby preventing disengagement of the key from the opening and the control system generates a verification signal indicating suspension of operation of the machine, and a disengaged position wherein the key is removed from the opening and the lock is disengaged from the second portion of the key so that the key can be removed from the safety switch assembly only upon receipt of a verification signal from the control system indicating suspension of operation of the machine.