GB344398A - - Google Patents

Abstract

344,398. Brakes. FREUND, B., 30, M³nchenerstrasse, Sch÷neberg, Berlin. Aug. 20, 1929, No. 28781/30. Convention date, Aug. 20, 1928. Divided on 317,735, [Class 40 (ii), Phonographs &c.]. [Class 103 (i).] Applied by speed-responsive devices.-Relates to hand-operated driving-mechanism for driving a sound or picture film, in recording apparatus, at a uniform speed, particularly for use in connection with the apparatus described in Specification 317,735. According to the invention, the driving mechanism comprises a spring through which the drive from a hand crank, rotated continuously or substantially so, is transmitted under the control of a governor to the film, so that irregularities in the rotation of the crank do not affect the movement of the film. Means may also be provided, whereby variations in the tension of the spring are automatically compensated for by action upon the governor. In the construction shown in Fig. 1, a hand-crank 140 drives a sound-record film 149 through a spring 141 and a train of gearing 143 .. 148. A centrifugal governor 147, driven from a wheel 146 of the transmission train, controls the speed. The governor includes a brake surface 160, the position of which relatively to the centrifugal weights is automatically varied by a tongs device 152, 158, which is so controlled by the spring 141 that as the spring expands the member 160 rises. Fig. 3 shows another arrangement wherein a handdriven spindle 200 winds up a spring in a drum 201, which, as it rotates, drives the film through gears 202, a shaft 204, and wheels 148, a governor 147 being arranged as shown to control the speed of the shaft 204. Epicyclic gearing 199, 210, 208 is so connected with the spindle 200 and the spring drum 201 that an arm 211 carrying the wheel 210 rotates around the axis 209 if the speed of rotation of the hand crank 30 and of the spring drum are unequal. By means of a member 212 mounted on the arm 211 and controlling the position of the part 160 of the governor, the action of the governor is automatically varied in accordance with changes in the tension of the spring as the wheel 210 moves in either direction around the axis 209. A pointer 213 moves over a scale 214, and may be adapted to operate bells or other signals to indicate when the maximum permissible change in tension of the spring has been reached in either direction. In a further construction (Fig. 2, not shown) a screw and nut device is used instead of and to serve the same purpose as the epicyclic gear shown in Fig. 3.