GB1529825A - Film counter device for a movie camera - Google Patents

Abstract

1529825 Film counters NIPPON KOGAKU KK 11 Nov 1975 [15 Nov 1974] 46578/75 Heading G2A A camera has plural counter scales, corresponding to different lengths of film, the counter moving through the whole of the particular scale which is being used, as determined by automatically set means responsive to the cartridge inserted, which has a characteristic (e.g. shape) indicative of the length of film therein. In Fig. 1, two gear-wheels 11, 12, fixed together, are mounted by a shaft 9 at the centre of a three-armed lever 8. In the position shown, gear 11 drives, via an intermediate gear 13, a gear 1b to which is fixed a counter dial 1a carrying two sets of footage scales, 0-50 and 0-200. This is the position for a standard cartridge containing 50 feet of film. During the picture-taking operation, the movement of the film is transmitted to gear 11, and hence to gear 1b, and so is shown on the dial 1 a, which turns through the full scale as the whole length of film is transported. If a large cartridge containing 200 feet of film is introduced into the camera, an additional part of the cartridge projects downwards to engage a slider 6 and push it downwards, from the Fig. 1 position to the Fig. 4 position. This pushes downwards the end 8a of lever 8 to pivot it anti-clockwise. Consequently gear 13 is retracted out of engagement with gear 1b, and gear 14 is now brought into engagement with gear 1b. Thus the film movement is now trasmitted to the counter dial via gear 14. The gear ratios are such that dial 1a now turns at a quarter of its previous speed, so that again it will turn full scale for the whole length of film, which is four times longer than in the standard cartridge. Fig. 6 shows another embodiment in which the film counter, instead of being a rotating dial as in Fig. 1, is a sliding pointer 21, whose end 21b reads against a linear scale (not shown). The pointer is moved by engagement with one of two worm rods 29 or 31, either of which can be rotated into engagement with the pointer by similar means to that described in the first embodiment.