Motography (Jul-Dec 1914)

August 8. N14. MOTOGRAPHY 211 Recent Patents in Motography By David S. Hulfish No. 1,059,067. For an Improved Film Trap Door. Issued to Edwin S. Porter, New York, N. Y.. assignor of half t'1 Francis B. Cannock, New York, \. Y. The illustration show. the tension clip or "trap door" of the film trate. 1,059,(67 This trap door consists of a plate c having a film window C2 and having two ears cj each with a notch at C4. The plate c is held in the film gate by hooking the ears cj over pins in the gate frame, where it is held by a spring latch arrangement. The whole plate c with its tension strips (to be described) may be readily unlatched and removed from the gate for inspection and cleaning. Secured to the film side of the plate c, and by means of small screws or slip dowel pins d, are two parallel resilient strips d2 which normally bear against the film to produce a tension and to prevent buckling in the film window, the strips being long and curved to extend downwardly around the intermittent sprocket just below the film gate, and being provided with slots at rfj for the teeth of the -sprocket so that the spring strips may bear directly upon the film and thus insure an exact relationship between the film and the sprocket by always pressing the film down upon the sprocket teeth. The spring latch arrangement for holding the trap door plate c is so arranged that the plate c may be held to press the strips d against the film, or may be held by a detaining finger to keep a clearance between strips d and the film and sprocket to permit the motion head to be threaded Up, the operation of the detaining finger to release the plate c then permitting that plate to slip for ward to grasp and thereafter to control the film. The claims of the patent read upon this last nun tioned feature. No. 1,059,276. For an Improved Intermittent Mechanism for Motion-Picture Machines. Issued to John C. Collins, New York, N. Y., assignor of half to Otto F. Miller, New York, N. Y. The intermittent sprocket is mounted upon a shaft which carries also a wheel 7 having four pins. These pins in the figures are numbered 17, 18, 19, 20. and are placed equally spaced around the wheel /. Reversing the order of the usual Geneva movement, where the pin wheel is the driving member of the intermittent pair, the pin wheel here is the driven member, being driven by a cam wheel 6. The cam wheel 6 is provided with an annular groove 11 which is not a complete annulus, but merges into operating passages 12 and 13. During the projection of a single image of the film, the two wheels 6 and 7 maintain the position shown by the figure at the left in the two figures of the patent reprinted herewith. The outside face of the wheel 6 engages the pins 17 and 19 while pin 18 is held in the groove 11. The intermittent wheel 7 therefore is held locked and motionless. Imagine now that the driving wheel 6 is turning rapidly in the same angular direction as the hands of a clock take, that is to say, with the top moving to the right, then soon end 21 of the outer portion of the wheel 6 clears from the pin 17 and at about the same time, the projection of the central portion of the wheel 6 strikes the pin 18, starting the pin wheel 7 to shift the film . The projection referred to passes between the pins ij and 18 and the movement of the wheel 7 by pin 18 causes pin IJ to move into the path of end 22 of the outer part of wheel 6 with the result that pin 17 is drawn fully into the groove 11 and pin 20 is drawn down upon the outside of the wheel 6, the point 22 passing under pin 18 and again locking the intermittent wheel 7. By proper design of the operating pathways 13 and 12 the shift of the intermittent wheel 7, and the shift of ,2o -7 the film therefore, may be made any desired fraction of the total revolution of the driving wheel, 6, and therefore may be made as quickly as desired. The first of the six claims of the patent as issued is very broad in its scope, and reads as follows :