| 摘要 |
<p>725,868. Automatic control systems for electric furnace electrodes. DELAWARE ENGINEERING CORPORATION. May 4, 1953 [March 5, 1953], No. 12253/53. Class 38 (4). [Also in Group XXXVII] In an arc-furnace electrode regulating system using a reversible electric winch motor, the counterbalance-weight is replaced by a continuously energized torque motor which exerts insufficient force to move the electrode by itself. The torque motor might be a solenoid and plunger, Fig. 3 (not shown), but is preferably a suitably rated motor belt or gear coupled to the winch motor or built in the same frame as the winch motor, Figs. 4-9 (not shown). A control circuit for the motors is shown, Fig. 10, wherein a Ward-Leonard generator 114, supplying the winch motor 120, has fields 107, 113, energized in accordance with the arc current and voltage respectively, and the torque motor 122 is supplied from a differentially compounded generator 123. For manual control fields 107, 113 are de-energized by switches 104a, 108 and field 116 is energized by switch 117; in addition the compounding field 129 may be shorted by switch 130, and the strength of the torque-motor field varied by resistor 124, to assist in raising the electrode.</p> |
