| 摘要 |
957,919. Cinematograph apparatus, intermittent film feed. FERNSEH G.m.b.H. Sept. 11, 1961 [Sept. 10, 1960], No. 32463/61. Heading G2E. In a cinematographic apparatus such as in. Fig. 1 in which film as at F is led through a region in which a claw as at G is periodically operative thereon to advance said film by a predetermined amount through a first clamping device as at K1 15 arranged to open periodically to allow the passage of film advanced by said claw into a storage loop as at 13 of predetermined minimum length between said first clamping device and a second clamping device as at K2, 15 arranged to secure said film in a gate as at 14 in which it is exposed to light or in which it is projected, said second clamping device is arranged to be briefly opened during periods in which said first clamping device is closed and said film is led subsequent to said gate in a curved path as at E through a region in which there is arranged to be produced (for example by suction means) between the two sides of the film a difference of pressure such as when said second clamping device is opened to cause said film to be rapidly drawn through said gate. As shown, the film is led to the claw S by means of a driven sprocket 10 and guides 11, 12. Claw S (as best seen in Fig. 7) is pivotally mounted at one end on a driven crank R2 and medially on a freely pivotable crank R1. The clamping cheek K1 of the first clamping device, pivoted at X1 is normally urged into its clamping position (shown) by a spring F1 and is periodically raised for releasing the film by the engagement between a bearing L1 and an eccentric E on a shaft El driving with non-uniform angular velocity through a double-crank drive (Fig. 8 - not shown). The clamping member K2 of the second clamping device is similarly pivoted at X2, is normally urged into its clamping position (shown) by a spring F2 and is periodically briefly displaced for releasing the film by the engagement between a bearing L2 and the eccentric E. The period during which member K2 is displaced is made shorter than the period during which cheek K1 is raised by suitable arrangement of said non- uniform velocity. After passing through said region where suction is applied, the film passes over a driven sprocket 16, over a guide pulley 19, over a sound drum 22, over another guide pulley 23 and is fed for example to a take-up spool (not shown) by way of a further driven sprocket 32. Guides 17, 20, 21 and 31 (Fig. 3) are provided for guiding the leading end of the film during threading. The suction chamber is also shaped to facilitate threading and member K2 may be held in its inoperative position for the same purpose by an anticlockwise rotation of a lifter A (Fig. 7) comprising three ground surfaces on a rotatable shaft. On further rotation of the lifter A, the cheek K 1 also becomes lifted and easy removal of the film from the apparatus is thereby facilitated. Further means for facilitating threading (as described in Specification 927, 830) comprise an electromagnet 24 which by means of a pull-rod 25 and wedgeshaped components 26, 27 oscillates the guide pulleys 19 and 23 in a horizontal direction (at 50 cycles per sec. ). Framing adjustment is obtained by moving the normally stationary pivot point M of the crank R1 (as fully described in the Specification with reference to Fig. 5, not shown). The Specification also describes a way in which the switch for the electromagnet 24 and the switches for the three motors for film transport, sound drum and suction may be coupled together. |
