Improvements in and relating to stop mechanism for talking machines

摘要

328,095. Garrard Engineering & Manufacturing Co., Ltd., Offen, F. J., and Butler, W. March 21, 1929. Brakes.-Relates to automatic stopmechanism of the kind comprising a screw spindle rotated by the turntable and a pawl engaging said screw and moved by the tone-arm. According to the invention, the screw spindle c is mounted for longitudinal displacement so that when the traverse of the pawl g due to the angular displacement of the tone-arm o is less than the advance of the screw-thread d on the spindle c due to the rotation of the spindle, the spindle is longitudinally displaced and releases a spring stressed braking mechanism which stops the turntable. As shown, the spindle c is slidably mounted in lugs e, e on a carriage f and is rotated by the shaft of the turntable b1 through a worm gear a, b. The pawl q is pivoted at q1 on a lever p pivoted at p' and formed with a slot p1 engaged by a pin o' on the tone-arm. The pawl is held against the screw thread by a spring r. When, at the end of a record, the tone-arm and therefore. also the pawl stops moving while the turntable and the screw spindle continue to rotate, the spindle moves towards and deflects a lever m about a pivot n, and this releases a lever j1 with a brake pad which is applied by a spring j3 to the turntable. At the 'same time, the lever j1 releases a lever g1, which then allows a spring f1 to turn the carriage f about the axis of the turntable and thus withdraw the screw thread beyond the reach of the pawl q, which is limited by the abutment of a pin q2 on the pawl against a plate s on the bed-plate z. To restart the machine, the tone-arm is moved back, and the brake swung out of action by a handle j; the lever j1 is then again caught by the lever m under the action of a spring m1, and lever carriage f is returned to the operative position by the lever g1. If desired, the manual resetting of the brake may be avoided by the provision of a double-armed lever t, t1 pivoted at t2. With this arrangement, when the tone-arm is moved back to the starting position, the lever t, t1 is deflected by the lever p and swings the brake lever j1 to the cocked or inoperative position.