Improvements in and relating to electric furnaces
552,511. Tilting furnaces. GROVES, W. W. (Moore, W. E.). Nov. 25, 1941, No. 15179. [Class 51 (ii)] A tilting furnace heated electrically is provided with a bracket or brackets 15, Fig. 3, pivotally engaging at 20 a support or supports 18 spaced from the furnace. The furnace is tilted by pivotally mounted hydraulic pistons 25 engaging with brackets 24 on the lower part of the furnace which in its normal position rests by means of feet 26 upon pedestals 30 pivoted at 29 to allow them to be moved into the position shown in dotted lines when it is desired to lower the furnace beyond its normal position so as to rest on supports 33. The furnace roof is raised and moved to one side by a piston rod 45, Fig. 4, rotatably secured to a piston 44 working in a hydraulic cylinder 43 secured to the wall of the furnace. The piston rod is provided with a roller 49 which, as the piston rod is raised, moves in a cam shaped slot 48 which allows the roof to be moved vertically at first and then both vertically and horizontally to clear the furnace. Fluid under pressure is supplied to the cylinders of the tilting and roof-lifting mehanism by a pump 53, Fig. 6, driven by an electric motor 54 and connected by a pipe 55 to a reservoir. When it is desired to tilt the furnace, fluid under pressure passes from the pump through a three-way cock 58 which is manipulated to direct fluid through a pipe 61 to a control valve 60 which is set to permit passage of fluid to a pipe 42 to the cylinders 22. When the furnace has been tilted, the valve 60 is placed in neutral position and fluid is returned from the valve to the tank 56 through the pipe 62. Should the furnace be overtilted, a chain 72 attached to the furnace operates a valve 71 and allows fluid to pass back through pipes 70, 68 to the reservoir. To lower the furnace to its normal position the valve 60 is operated to allow fluid to drain back from the cylinders through the pipe 42, valve 60 and pipe 68. When it is desired to raise the roof, the valve 58 is manipulated to allow fluid to pass to the pipe 64 and control valve 63 which is operated to allow fluid to pass through a pipe 67 to the cylinder 43. An overflow passage 52, Fig. 4, is provided in the cylinder 43 of the roof lifting piston to prevent excessive upward movement of the roof. Safety switches 80, 84 and 86 are arranged in the electric circuit of the motor 54 to limit the tilting of the furnace and to prevent operation of the roof and tilting of the furnace simultaneously.