9 SWITCHES AND SENSORS FOR USE WITH MACHINERY, NAMELY, PROXIMITY SWITCHES OR SENSORS, PHOTOELECTRIC SWITCHES OR SENSORS, VIBRATION DETECTING SENSORS, PRECISION POSITIONING SENSOR, DISPLACEMENT SENSOR, METAL PASSAGE CONFIRMING SENSORS, DOUBLE FEED DETECTION SENSORS, PRESS MACHINE STROKE END DETECTION SENSOR, ROTATION RUNOUT SENSOR, TAPPING MISS DETECTION SENSORS, WELDED PORTION POSITIONING SENSORS, NON-CONTACT SIGNAL COUPLER, FIBRE OPTIC PHOTO-ELECTRIC SENSORS, OUTER DIAMETER AND WIDTH MEASURING GAUGE, DOUBLE SHEET DETECTORS, OPTICAL DISPLACEMENT SENSORS, AND RAY SCALE OPTICAL MICROMETER