| 摘要 |
1,204,274. Detecting flows photo-electrically. REYNOLDS METALS CO. Oct.14, 1968, No.48656/68. Heading G1A. In a method and apparatus for testing for perforations the side-walls and bottom of an open ended hollow body 10 having highly reflective interior surfaces the outside of the body is immersed in light and any light passing into the can through a perforation is detected in a sensor 24 mounted on the can side of a member 22 arranged to be brought into light tight engagement with the open end. The body may be pressed against a conical surface 18 to form the light seal by a transparent plate 20, and any detected light may control "accept" "reject" mechanism. The sensor may be protected from damage from the light when a can is not in position by switching off the lights or by a cover. The body may be passed through a succession of stations in which the hold-down plate is differently orientated. |
