Patent GB-1401854-A (GB)
Title: Inspection of ampoules
IPC: B07C5/342
Filed: 1972-08-02
Abstract: 1401854 Photo-electric sorting apparatus TAKEDA YAKUHIN KOGYO K K 2 Aug 1972 36127/72 Heading G1A [Also in Division G4] Ampoules having foreign bodies or dirt are sorted from clean ones by a system utilizing a television camera, the video signal from which is analyzed to detect defective ampoules. In the arrangement of Fig.1, ampoules from a feeder disc are transported by disc B to a means C for rotating them at high speed before presentation to the photo-electric inspection station. The latter comprises illumination source D and a T.V. camera F which views (in this arrangement) two ampoules crossing its field of view. The camera circuit, Fig.2, includes a Schmitt trigger K which determines from the signal amplitude the presence of a foreign body in an ampoule. In order to identify such a defect as relating to a particular ampoule, gating circuitry is provided to blank out video signals outside areas X, Y Fig.4A corresponding to the parts of the ampoules A 1 , A 2  of interest, these blanking signals being developed from the horizontal and vertical synchronizing pulses from oscillator OSC, via monostable M 10  and monostables M 11 , respectively, as applied to monostables M 1 , M 2  and to monostables M 3 , M 4  and M 5 , M 6 . Monostables M 11  are used in association with a "correction" circuit CN 3 , M 12  M 13  (with switch SW in position S 2 ) to cause a non-blanked window X to follow an ampoule across part of the field at which point the same ampoule is then followed by window Y. As this occurs, the gating circuit AND 1-3 etc, arranges that defect pulses from K associated with window X are fed to one counter CN 1  and those associated with window Y to the other counter CN 2 . The counters may only generate an output if a predetermined count is reached indicative of a defective ampoule. Since each ampoule is counted twice, means are provided in the form of photocell 17, indicating by detecting the position of a later ampoule when an ampoule has reached a particular position in the camera field of view, to control resetting of the counters (the output of CN 1  being stored in register SR 1  to await the count for the same ampoule made by CN 2 ) and of the windows to their initial positions. The information representing a defective ampoule is subsequently passed via delay register SR 2  &c. to a rejection mechanism MG, Fig.2, in Fig.1 being shown as an electromagnetically operated bar 21 which pushes the ampoule from collector disc 14 to collector 15. In the circuit of Fig.2, if switch SW is in position S 1 , the "correction" circuit is ineffective and no following of ampoules by the unblanked windows occurs. The system may be monitored by display M. Various modifications of the Fig.2 system are described. In Fig.5 (not shown), ampoules move in the horizontal direction across the field, so that horizontal synchronizing correction signals are developed instead of vertical to enable following in this direction. In Fig.7 (not shown), detection of ampoules in a particular position in the field is by operating on the video signal instead of the use of the photo-cell 17 of Fig.2. Fig.8 (not shown) substitutes for the shift register SR 1  and OR gate OR 1 , a gating arrangement controlled by a flip-flop switched by the resetting means. When more than two ampoules simultaneously cross the camera field, the appropriate number of counters and associated gating circuits will be provided.