| 摘要 |
The present invention embodies a safety interlock system and method for automatically disabling operation of a robot or other machine with standard mechanical interfaces (SMIF) apparatus if the components are not in proper operating positions when the machine is started. In a preferred embodiment the safety interlock is incorporated in a robotic machine for processing semiconductor wafers and the system uses three conventional sensors for detecting whether the transfer robot is in the out position or not, whether the cassette elevator is "home" or not, and whether the cassette gripper on the transfer robot is open or closed. A logic circuit has the outputs of the robot "out" sensor and the cassette elevator "home" sensor input to a NAND gate, the output of which is input to an OR gate along with the output of the "open" sensor of the SMIF robot arm gripper. An appropriate output from the OR gate lights an LED setting off an audible alarm and opening a breaker that automatically disables the SMIF robot motor. Thus, when the machine is started, the system checks the outputs of the three sensors and if no output results from the OR gate the SMIF apparatus goes to work. If an output from the OR gate does result, the alarm is set off, the breaker is opened disabling the SMIF apparatus and preventing further machine operation.
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