Abstract: A coal planer for use in an underground mine gallery comprises a central unit, a pair of loading heads arranged spaced from and to opposite sides of the central unit and a pair of intermediate units respectively located between the central unit and the loading heads and linked to the latter and the central unit. Each of the intermediate units is provided with a plurality of planing knives arranged vertically spaced from each other for cutting coal from the mine face during reciprocation of the coal planer in a direction parallel to the mine face, and with a bottom knife adapted to cut into the sole of the mine gallery.

Abstract: An injection-molding machine has a drive ram with a pressurizable chamber that can be connected either to the high-pressure side or the low-pressure side of a source of fluid under pressure. A control system operating this machine has a pressure-reducing valve with an inlet port connected to the high-pressure side of the source, an outlet port connected through a cut-off valve and a throttle to the chamber of the ram, and a pilot port pressurizable to control the pressure at this outlet port. A pressure-relief valve has an inlet port connected to the pressurizable ram chamber, an outlet port connected to the low-pressure side of the pressure source, and a pilot port pressurizable to control the pressure differential across this pressure-relief valve.

Abstract: A mine roof support comprises a support member adapted to rest on the floor of a mine gallery, a first shield projecting upwardly from the rear end of the support member, a second shield pivotally attached at its lower end to the upper end of the first shield, an expandable and contractable prop between the support member and the second shield for changing the inclination of the latter and a cap adapted to engage the roof of the mine gallery pivotally attached between its ends to the upper end of the second shield to form between the upper surface of the latter and the bottom face of the cap a wedge-shaped space directed away from the face of the mine gallery.

Abstract: A charge of ore, pellets, sinter and the like is admitted into the top of a shaft furnace. In the upper region of the furnace, there are provided inlets through which a reducing gas is introduced into the furnace. Direct reduction of the charge takes place in the upper region of the furnace and yields iron sponge. The iron sponge forms a column in the furnace which extends from the upper region of the furnace into the lower region of the latter. A burner extends into the lower region of the furnace and continuously directs a flame against the lower end of the sponge column. As the iron sponge in the lower portion of the column melts, fresh iron sponge descends through the furnace and becomes exposed to the flame so that the iron sponge is continuously melted. The molten material is continuously withdrawn from the furnace. The charge may include alloying elements so as to permit alloying of the molten material to produce a steel having a desired composition.

Abstract: A multi-partite guide roll which is especially usable in continuous casting installations has a plurality of axially arrayed discrete roll sections which are connected by stems so that they are compelled to rotate jointly about a common axis. The stems may either be provided at one axial end of the respective roll sections and extend into an axial recess of an axially adjacent roll section, or the roll sections may each have axial recesses at their opposite axial ends and the stems may be separate elements having two end portions each received in the axially aligned recesses of two axially adjacent roll sections.

Abstract: Metal fibers are produced in a magnetic field by generating magnetic flux lines which extend normal to a planar supporting surface located in an enclosed space. Metallic substances are fed into the enclosed space for travel lengthwise of the flux lines and normal to the supporting surface. The space is heated to a decomposition temperature at which the substances undergo thermal decomposition and liberate metal atoms which agglomerate under the influence of the flux lines on the supporting surface and form thereon metal fibers which project from the supporting surface in direction normal thereto. The supporting surface is then moved in the direction of travel of the incoming metallic substances past a fiber transporting device, and when it has moved to a position downstream of the fiber transporting device, the fiber transporting device engages the fibers and effects their further transportation.

Abstract: An injection-molding apparatus for making ceramic moldings has a mold provided with a mold cavity, a structure formed with a passage which communicates with the mold cavity, and an injecting arrangement for injecting the molding material via the passage into the cavity. The injecting arrangement has a cylinder a front end of which is provided with an outlet communicating with the passage, and which also has a material inlet rearwardly spaced from the outlet. A ram is reciprocable in the cylinder between a first end position in which it is located rearwardly of the inlet and another end position in which it is located forwardly of the inlet and close to the outlet. The ram carries a rearwardly extending skirt which extends across the inlet when the ram is in its forward or second end position, so as to prevent material from entering the cylinder behind the ram through the inlet.

Abstract: An advancing excavation roof support has a base and a shield assembly above the base. The base has two base portions which are spaced from one another at its end which faces toward the face of the excavation, and a lifting member is mounted between the two base portions for pivoting about an axis. A hydraulic cylinder-and-piston unit extends between the base and the lifting member and pivots the latter about its pivoting axis between a retracted position in which the lifting member is out of contact with the excavation floor, and an extended position in which an engaging portion of the lifting member engages the excavation floor and is downwardly spaced from the base so that the one end of the base which faces the excavation face is elevated and digging thereof into the excavation floor is prevented.

Abstract: A charge consisting of scrap, sponge iron, pellets and the like is admitted into a vertically arranged melting chamber so as to form a column therein. A burner lance generates a flame which melts the column from below so as to produce a melt and an FeO slag. A transportable and tiltable vessel is provided beneath the melting chamber and contains a quantity of pig iron. The melting chamber has an opening at the bottom thereof through which the melt and the slag flow into the vessel to form a mixture containing between 30 and 60 percent by weight of pig iron. Alloying elements and cooling agents are added to the mixture and the resulting molten mass is then at least partially refined in the vessel by blowing with oxygen. During the blowing operation, reaction of the slag and the pig iron occurs and a pourable steel having a desired composition is thereby obtained.

Abstract: A charge consisting of scrap, sponge iron, pellets and the like is admitted into a vertically arranged melting chamber and forms a column therein. The leading end of the column is melted with an annular flame generated by means of an annular burner or a plurality of burners arranged circumferentially of the melting chamber. In this manner, a downwardly extending projection is formed within the confines of the periphery of the leading end of the column and this bears against the bottom of the melting chamber thereby supporting the column. An outlet for the molten material is provided in the bottom of the chamber and this is surrounded by a projection extending upwardly from the bottom of the chamber. The latter projection is effective for permitting the molten material to remain on the bottom of the chamber for a short period prior to its outflow from the chamber so that the molten material is superheated by the flame.

Abstract: The output of the sensor whose variations are to be compensated is applied to one input of a DC amplifier whose other input is connected to an analog storage. The output of the DC amplifier is applied to a voltage-controlled oscillator whose frequency varies as a function of the voltage applied thereto. A phase detector compares the output of the voltage controlled oscillator to a standard reference frequency and furnishes a DC compensating voltage corresponding to the difference therebetween. Prior to each measurement the DC compensating voltage is applied to the analog storage thereby forming a closed loop circuit and causing the voltage controlled oscillator to oscillate at its standard frequency. At the start of the measurement the connection between the phase detector and the analog storage is broken thereby causing the DC compensating voltage present at the beginning of the measurement to be applied to the DC amplifier throughout the measurement.

Abstract: A charge consisting, for example, of scrap, and/or ore, pellets, sinter and the like, is admitted into a vertically arranged melting chamber and forms a column therein. The leading end of the column is melted with an electric arc which is preferably generated by means of a plurality of electrodes arranged circumferentially of the melting chamber so as to be of annular configuration. In this manner, a downwardly extending projection is formed within the confines of the periphery of the leading end of the column and this bears against the bottom of the melting chamber thereby supporting the column. If necessary, the charge may be reduced in the melting chamber prior to being melted. An outlet for the molten material is provided and may be located in the bottom of the chamber or in the wall of the chamber.

Abstract: A magnetic field is generated whose flux lines extend normal to a planar supporting surface which is located in an enclosed annular space. Carbonyls of metallic material are fed into the enclosed space so that they travel lengthwise of the flux lines and normal to the plane of the supporting surface. The space is then heated to a decomposition temperature at which the carbonyls undergo thermal decomposition and liberate metal atoms which agglomerate under the influence of the flux lines on the supporting surface and form on the latter metal fibers which project from the supporting surface in a direction normal thereto, i.e., opposite to the direction of travel of the carbonyls themselves.

Abstract: Particulate material such as iron scrap is melted down into a melt which is received in a melt retaining zone. During the reception of the melt in this zone, liquid iron of the melt is contacted with an elongated upright body of carbon soluble in the liquid iron, or with a lining of such carbon adherent to the bottom of the melt retaining zone, below any slag which floats on the liquid iron of the melt. The liquidus point of the melt is lowered by the resulting carburization of the iron, thereby facilitating the retention of the liquid iron in the melt retaining zone.

Abstract: An injection molding machine wherein a screw rotates and reciprocates in a barrel to plasticize granular synthetic material and to expel plasticized material into a mold. The screw is reciprocated by the piston of a hydraulic cylinder one chamber of which is connected with the outlet of a first pressure relief valve which determines the pressures of fluid while the screw moves forwardly to expel plasticized material, and with the inlet of a second pressure relief valve which determines the pressure of fluid while the screw moves rearwardly during plastification of granular material. The pressure relief valves are controlled by a pressure selecting valve which, in turn, is controlled by a programming unit. The inlet of the first pressure relief valve is connected directly with a line for highly pressurized fluid, and the outlet of the second pressure relief valve is connected with the tank.

Abstract: Iron ore is continuously converted to steel by introducing the ore into a shaft furnace of substantially equal cross-sectional width and thus forming a column of the charge therein; introducing a reducing gas into the furnace and exposing the bottom portion of the charge column from below to the heat of an electric arc the source of which is centrally disposed in the bottom of the furnace and thus causing the gradual super-heating and melting of the bottom portion of the charge so as to form a dome-shaped cavity at the bottom of the charge column while the column gradually moves downward under the force of gravity and collecting and tapping the formed molten steel at the bottom of the furnace.

Abstract: Particulate material such as scrap, sponge iron, prereduced pellets and the like is introduced into the top of a vertically arranged melting chamber and forms a column in the latter. The material is melted by directing a flame or an electric arc against the lower end of the column and the melt thus formed collects at the bottom of the chamber. As melting continues, fresh particulate material travels downwardly through the melting chamber to become exposed to the action of the flame or arc. A projection is provided at the bottom of the melting chamber and has an upper surface which is located above the level of the melt. The flame or arc is so adjusted that a portion of the lower end of the column bears against the upper surface of the projection. In this manner, the column is supported in the chamber without contacting the melt so that excessive loss of heat from the melt is prevented.