| 摘要 |
PROBLEM TO BE SOLVED: To prevent the malfunction of reed switches and to extend the life of a position detecting device by controlling a switching element with the outputs of the reed switches responding to a magnet fitted to a piston, and allowing light emitting bodies to emit light. SOLUTION: When drive air is fed to a cylinder and a piston having fitted magnet is slid in a cylinder main body, reed switches 2, 3 fitted to the outer periphery of the cylinder main body and serving as detecting means are connected together by the magnet fitted to the piston when the piston is located in a prescribed range. When the reed switches 2, 3 are connected together, the control terminals for transistors 14, 19, 21, 22 connected in series to the reed switches 2, 3 and serving as switching elements are excited. A power supply is connected to one side of the switching elements via an input terminal 11, red and green diodes 16, 20 serving as light emitting bodies are connected to another side, thus the light emitting bodies emit light. The amount of current flows in the reed switches 2 is little, 3 because they are excited via the switching elements. |
