GB541463A - A kinematograph projector with continuous film feed - Google Patents

Abstract

541,463. Kinematograph projectors. KOLB, O. K. (Electrical Fono-Films Co. Aktieselskab). Dec. 10, 1940, No. 17502. [Class 97 (i)] In a continuous-feed projector having two rocking mirrors alternately operative to effect compensation, the mirrors are mounted on separate co-axial spindles alternately rocked by arms engaged by pins on the two faces of a rotating drum, and the spindles are reciprocated axially by a guide pin engaging a sinusoidal channel cut in the curved surface of the drum. As shown, the film 1 is drawn over rollers 2 and through a curved two-picture gate 3 by a sprocket 6, and the projecting beam is reflected by one or both of rocking mirrors 10, 11 through a projection lens 12 to an adjustable mirror 13 reflecting to the projection screen. The mirrors 10, 11 are respectively carried by co-axial spindles 15, 16, Fig. 2, provided with arms 18, 21 loaded by springs 39, 40 and engaging opposite faces of a drum, 24 on the spindle 27 of the sprocket 6. Each arm has an outwardly bent face 19, 22, the faces being alternately engaged by pins 20, 23 on the drum so that each arm is rocked by such engagement until it engages a fixed stop, and is afterwards flexed so as to load the spring associated with it. The outwardly bent face ultimately slips off the pin engaging it, and the spring and the flexure return the arm to its initial position. Axial reciprocation of the spindles is effected by a pin 32 engaging a sinusoidal channel 25 on the drum 24 ; the pin 32 is carried by a blade spring having a frequency equal to that of the reciprocation. The relative positions of the parts may be modified, and the image projected by the lens 12 may be formed in an adjustable framing aperture carrying a field lens, a further lens being provided to project the screen image therefrom.