| 摘要 |
PURPOSE:To prevent damage to a machine device and an injury to an operator by providing a switch group for manual mode with an abnormal signal detecting circuit and making execution in manual mode in effective if there is abnormality in switching to the manual mode. CONSTITUTION:The outputs of operation switches PB1-PB4 for the manual mode are supplied to the abnormal signal detecting circuit 1 and also inputted to an OR gate OR1. If a manual mode selection switch S2 is pressed during the execution in automatic mode selected with an automatic mode selection switch S2, an interlocking switch S1-1 is turned on. For example, when the return spring of the PB1 is broken and contacts X1-a1 and Y1-b are left open, a relay Z1 does not operate and no output is sent to a manual mode gate 2. Therefore, the manual mode of a control element 3 is ineffective although there are the outputs from the OR1 and manual mode switch S1 to a manual mode gate 2. |
