GB137583A - Improvements in sound reproducing machines - Google Patents

Abstract

137,583. Marks, E. C. R., (Cheney Talking Machine Co.). Jan. 9, 1919. Periodic; applied by springs.-Relates to automatic stop-mechanism for talking-machines, of the kind in which the stop member, brake or switch, is brought into operative position by a spring upon the release of a latch by the tonearm, and consists in operating the latch by a trigger lever frictionally connected to the arm that is engaged by the tone-arm. Fig. 2 is a plan view showing the brake lever latched in its in. operative position. The brake lever 18 has a friction pad 20 and a handle 38, and is pivoted on a pin 19 to the base-plate 4. Two shoulders 25, 27 on a lever 18 co-operate with corresponding projections cn a latch member 23 also pivoted to the base-plate 4. A trigger lever 26, fitting loosely in the forked outer end of the latch, is pivoted on a pin 28, and is frictionally connected to the operating arm 29, which is pivoted on the same pin 28 and has an upstanding outer end 41. The frictional connexion comprises an arm 32 of the operating-lever 29, overlying an arm on the trigger lever 26, the two arms being pressed together by a spring surrounding the bolt 34. A segmental slot is provided on the upper arm 32, to enable the position of the operating-lever to be adjusted relatively to the trigger 26. In the position shown in Fig. 2, the brake is held off by the engagement of a projection on the latch 23 with the shoulder 25 on the brake lever. When the tone-arm reaches the final groove of the record, a member 13 moving with the tone arm engages the end 41 of the operating-lever 29, and after a certain delay due to the lost motion between the trigger 26 and the latch 23 the latter is tripped and the brake block 20 is brought into engagement with the inner side of the turntable rim 22 by means of a spring 21. The spring is attached at one end to a lug on the brake lever and at its other end to a lug on the trigger. Initial setting is effected by moving the arm 29 over to the left, placing the tonearm in its final position, and then moving the arm 29 by hand until it reaches the member 13 attached to the tone-arm. During the setting operation, the pin 40 forms an abutment for the trigger 26. The arm 13 is attached by a screw 11, and lugs 15, 16 to a tubular member 10 which surrounds the stationary socket 8 and is connected to the tone arm elbow by the screws 11 and 12 which move in slots in the socket 8. In a modification adapted for electrically-driven machines, the lever 18 has no brake block, but is provided with an arm, the outer end of which bridges a pair of fixed contacts in the motor circuit during the running of the machine, and opens the motor circuit when the machine is to be arrested.