摘要 |
A safety switch is described in which a switching contact in a lock mechanism switches between an open and closed condition. Switching is coupled to a lock member moveable between a locked position, locking a drive cam, and an unlocked position, allowing the cam to rotate. A link member, cooperating with the lock member, switches between open and closed conditions of normally-open and normally-closed switching contacts, indicating movement of the lock member between the locked position and the unlocked position. By monitoring the open and closed conditions of the normally-open and normally-closed switching contacts, it is possible to determine the state of the lock member, i.e., whether it is in the locked position or in the unlocked position. It therefore can be determined whether the drive cam is in the locked or unlocked (i.e., free to rotate) state.
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