DEFECTIVE DETECTOR

• Main Authors: IDA YOSHIAKI, TANAKURA ISAMU
• Format: Patent
• Language: English
• Published: 05.09.1987
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS; SEMICONDUCTOR DEVICES; TESTING

PURPOSE:To detect inferiority of a reed at a high speed by scanning laser beams circularly with respect to a reed frame and counting the time of light transmitting through the reed frame. CONSTITUTION:The laser beams emitted from a laser device 11 are made incident in parallel in a rotation shaft 4a of a motor 4 and reflected in the vertical direction to the rotation shaft 4a by a 45 mirror 6 provided to the tip of the rotation shaft 4a. Further, a conical mirror 7 is smaller than 45 deg. with respect to the rotation shaft 4a and light reflected by the mirror 7 is converged on the rotation shaft 4a. Then, the circular scanning is performed on the surface of the reed frame 3 and further, since the motor 4 is moved in parallel to the rotation shaft 4a on a mobile stage 5, it crosses a reed part of the frame 3. At this time, the light is cut by the reed part and the light is transmitted through between the reeds and the diffused 14 light is converged 10 and converted into an electrical signal and the time corresponding to the reed width and intervals is measured with a processing circuit 12. Further, the distance corresponding to the time at the point of time is calculated from the rotating speed of the motor 4 and the mobile position of the mobile stage 5 with the circuit 12 and if it is detected whether the reed width and intervals are over the set values respectively, a defective can be detected.