GB599848A - Improvements in furnace electrode regulators - Google Patents

Abstract

599,848. Fluid-pressure servomotorcontrol systems. DELAWARE ENGINEERINC CORPORATION. April 17, 1944. No. 7089. Convention date, Aug. 12, 1943. [Class 135] [Also in Group XXXV] The position of an electrode 52 in an electric arc furnace is adjusted in accordance with the current flowing by means of a piston 54 connected to the electrode and working in a hydraulic cylinder 55 in which liquid pressure is controlled by a reversible pump 57 interposed between the cylinder and a tank 59, and the pressure in the latter compensates for leakage in the system and serves to counterbalance the electrode and its support. The pump is driven by an electric motor 62 controlled by an apparatus 63 susceptible to changes in the current flowing through the electrode. An air cushion above the liquid in tank 59 is supplied with pressure air from a compressor 60, although the air cushion may be dispensed with by elevating the tank. The Specification as open to inspection under Sect. 91 comprises also an apparatus wherein the movement of the piston 14, Fig. 1 (Cancelled), is regulated by a valve 17 inserted between the Cylinder 15 and a hydraulic pressure tank 19, the valve 17 being controlled by the regulator 33. When the electrode is to be lowered, valve 17 allows the liquid in cylinder 15 to flow to a reservoir 21, the pressure in which is just sufficient to balance the weight of the electrode &c. As the level of the liquid in the reservoir rises, a float-operated switch 34 starts a motor and pump 24, 23 to pump liquid, e.g. hydro. carbon oil, from the reservoir to the pressure tank 19 past a check valve 25. The pressures in the tank and reservoir are maintained either by forcing air from compressors 27, 30 into the tanks to form air cushions above the liquid, or by elevating the tanks. This subject-matter does not appear in the Specification as accepted.