| 摘要 |
1,136,313. Counting-apparatus. AGFAGEVAERT A.G. 22 March, 1966 [22 March, 1965], No. 12447/66. Heading G4D. [Also in Division G2] An apparatus for examining or reproducing a preselected frame of recorded material on a web (4) (e.g. a microfilm viewer) comprises (Fig. 1, not shown), two storage rollers (2) and (3) for the web 4 which may be passed from one storage roller to the other via rollers (6), 7 and (9) and a film platform (5) at which the web is examined or reproduced. As shown in Fig. 2, a cam 12 on a disc 11 on the spindle 8 of roller 7 co-operates once per revolution with a spring biased lever 13 to complete the electric circuit of an impulse acutated addition-subtraction counter which thus records the length of film passing the roller 7 by the number of revolutions of said roller. The film may be moved either backwards or forwards, the counter being operated accordingly by means of a switch 17 which is connected with a master switch for forward and reverse running or with a friction bearing. The web may be programmed by forming a signal notch in its lead portion which automatically zeros the counter. A particular frame or series of frames may be selected for viewing by observing the counter or by using a preselector coupled to the counter. In other embodiments the lever arrangement of Fig. 2 may be replaced by a micro-switch or a photosensitive device, and/or the disc 11 may have a plurality of cams 12. |
