| 摘要 |
<p>968,802. Electric correspondence control systems. AEROPROJECTS Inc. March 29,1963 [March 30, 1962], No. 12671/63. Heading G1N. [Also in Division B3] The frequency of the A.C. power fed to a mechanical, work-performing, vibratory device is controlled by a temperature-sensitive resistor to vary with temperature in the same manner as the resonant frequency of the transducer coupling, so as to maintain optimum power-developing conditions. As shown (Fig. 3) a temperature-sensitive resistor 18 is connected across the cathode biasing resistor 58 of a valve 52, whose anode is connected to the grid through resistor 64 and capacitor 62, 68 whereby the output appears to be an inductance in parallel with a resistance. This is fed across the tank coil 86 of an oscillator valve 88, so that an increase in temperature of resistor 18 increases the transferred inductive reactance and reduces the oscillatory frequency of valve 88. The work-performing vibratury device is an ultrasonic welding transducer (Fig. 2) comprising a slotted member 24 of a magnetostrictive metal, or an electrostrictive ceramic, having a coil 28 fed with the controlled frequency A.C. power, and a coil 30 to supply polarizing flux. The member 24 is attached to a conically-shaped coupling element 32, rotated by a shaft 39 which also drives an anvil 46, the metal members 42, 44 to be welded together being located between the anvil and the end of the coupling element 32. The temperaturesensitive resistor 18 is embedded centrally inside the coupler 32, or attached to its surface. Specifications 837,869 and 877,966 are referred to.</p> |
