| 摘要 |
PROBLEM TO BE SOLVED: To reduce costs by simplifying the constitution of a detecting circuit and also to provide a detecting method for abnormality such as dents in press working by which the ride of refuse on the surface of a lead frame that is apt to generate at the time of punching the lead frame with a press die is rapidly detected and the generation of the flaws on the surface of the lead frame by adhesion of ridden refuse is suppressed to a minimum. SOLUTION: By irradiating the surface of a lead frame after punching with irradiating light 8 with a light emitting element 7 of a light emitting diode LED and also receiving the reflected light from the surface of the lead frame with a light receiving element 9 of a photodiode PD, the abnormality on the surface of the lead frame is detected. By irradiating the irradiating light at the inclination of an incidence angle of the irradiating light in the range of 20-70 deg. to the surface of the lead frame, preferably by inclining the incidence angle at about 45 deg., the abnormality on the surface of the lead frame is detected with a photosensor 6 in which the light emitting element 7 and light receiving element 9 are integrally mounted. |
