| 摘要 |
505,177. Automatic control systems. HARDINGE CO., Inc. Nov. 1 1937, No. 29830. Convention date, Nov. 1.1, 1936. [Class 38 (iv)] Sound output.-The rate of feed to a mechanism is automatically controlled by the sound vibrations produced, these being converted into electrical power variations in a control circuit in which the amplitude of such power may be adjusted to a predetermined noise level. Thus a microphone adjacent to a ball mill, and in series with an adjustable resistance and the primary winding of a transformer, may cause current variation in a secondary circuit containing a rectifier, a relay, and a current indicator, and the resistance may be set so that the relay will respond at a given noise level to effect control of an electric motor operating feeding means. The motor circuit may be controlled through a second relay having a time delay, for example a thermal switch having a heating winding controlled by the first relay. The Figure shows a mill 11 and a motor 116 operating feeding means 113. Three energy sources 140, 141, 142 may be added in sequence in the motor circuit to give three feeding speeds, by the operation of two relays 145, 132, the three operating windings of which are selectively controlled by a damped relay 123 receiving rectified current from an amplifier 121, the input to which is controlled by a microphone 120 and means 122 for adjusting the amplifier output. |
