Abstract: The invention relates to a lock mechanism for doors, preferably for use with dwellings, apartments or offices, the locking mechanism providing in particular a measure of safety against unauthorized opening of the lock. The lock mechanism is of a type which at will may be alternatively actuated from the inside either by a key or a thumb turn. When the resident of the house leaves he may in a simple manner suspend the function of the thumb turn. The lock is on its inside equipped both with a key hole hand and a thumb turn. The thumb turn may be engaged or disengaged with a dead bolt by means of a screw means. The screw means is actuated from the front of the lock, actuating an arm which actuates a transmission element bringing the transmission means of the thumb turn into, respectively out of engagement with the transmission means on the follower so that the lock at the operators will either will be actuated by a key or a thumb turn.

Abstract: Heated molten material is circulated in a closed cycle between a heater and a storage tank. The heater is controlled to maintain the temperature of the circulating fluid at a predetermined level. A replenishment supply of solid material to be melted is mixed with the heated fluid during retention in a melting container during the circulation from heater to storage tank.

Abstract: Method of producing aluminiumchloride with a low content of magnesium from hydrochloric acid solutions which contain ions of aluminium and magnesium and from which the aluminiumchloride is precipitated by hydrochloric gas and where the precipitation is carried out continuously in cascade so that the major part of the aluminium will be precipitated from solutions in which the ratio between aluminium and magnesium calculated as g Al.sup.+3 /g Mg.sup.+2 is above 0,5. Produced aluminiumchloride may be transformed to aluminiumoxide by calcination.

Abstract: Method of producing aluminiumchloride with low contents of iron from solutions containing ions of aluminium and iron by precipitation of aluminiumchloride by means of hydrochloric gas where the solution from which the aluminiumchloride is precipitated contains at least 0.1 g Fe/l which solution has been formed by leaching of a natural mineral raw material or artifically produced aluminium-containing raw material by leaching with hydrochloric acid and/or sulphuric acid, respectively a mixture of such acids. The produced aluminiumchloride may be transformed to aluminiumoxide by calcination.

Abstract: A direct current smelting furnace is disclosed. The anode and cathode are series connected electrodes, both of which are immersed in the furnace charge. A plurality of pairs of electrodes is preferably employed.

Abstract: A method of detecting flaws in metal members is disclosed. The metal member is exposed to high frequency heating whereupon the temperature profile across the work piece is measured, preferably by recording with an infrared camera. The recorded data can be used for automatic marking or repair of the metal member.

Abstract: An improved roof for covered electric smelting furnaces is disclosed. Cooling pipes are disposed on the outside of the roof and are of sufficient capacity and spacing to maintain a temperature on the inside of the roof of 150.degree. C.-400.degree. C. A sealing arrangement for adjacent sectors of the roof is also disclosed.

Abstract: An apparatus providing a gas tight seal for electrodes in covered electrical smelting furnaces is disclosed. The apparatus is characterized by hydraulic hoses which permit movement of the electrodes and their associated holders without loss of a gas tight seal.

Abstract: A latch handle of the type having a lever which rotates about a shaft normal to one end is locked by a key-controlled pin engaging the second end of the lever.

Abstract: A construction for a non-powered trailer to be towed by a motor vehicle is disclosed. A trailer frame is provided to which a plurality of different bodies can be affixed. In addition, the trailer is adaptable to be readily stored in a vertical position whereby storage space is substantially reduced.

Abstract: Improvements in matte smelting are disclosed. A circular furnace is formed having a concave bottom, the radius of curvature of the bottom being no greater than the diameter of the circular furnace. The matte level is controlled to cover not more than half of the concave surface bottom. Advantageous positioning of the electrodes, tapping holes, feed chutes and the like are also disclosed.

Abstract: A method of producing mechanically strong sintered pellets suitable for consumable use in smelting furnaces from non-oxidizable metal oxides is disclosed. The metal oxide is combined with a carbon-containing material whereafter the formed pellet is sintered in a shaft furnace.

Abstract: A method of producing sintered pellets containing metal oxide is disclosed. The pellets obtained are mechanically strong and are produced at substantially less cost than is encountered with known methods.

Abstract: Lock apparatus comprising a housing in which is movably supported a locking member for movement between locked and unlocked positions. The housing and locking member have aligned bores containing blocking pins supported for movement between a first position in which the locking member is movable relative to the housing and a second position in which the blocking pins block movement of the locking member relative to the housing. A plate-like key member and a plate-like code member are respectively insertable into slots provided in the housing. The bores in the housing and locking member are arranged in a predetermined pattern and the plate-like members have respective regions corresponding to the location of the bores in the pattern.

Abstract: A system for the continuous analysis of furnace gasses for carbon dioxide and oxygen levels is disclosed. Materials which would be detrimental to the measuring instruments are removed before the gasses reach the measuring instruments. In particular, moisture content is removed by condensation at temperatures near freezing whereafter the gas is permitted to continuously warm up as it goes through the measuring instruments so that no condensation takes place in the measuring instruments.

Abstract: A method of disposing of silica dust precipitated from metallurgical furnaces producing products high in silicon content by making mechanically strong metal oxide pellets with the silica dust as a binder is disclosed.

Abstract: A gas purification device comprising substantially concentric chambers separated by a filter tube is disclosed. The filter tube forms a common wall between adjacent chambers. Gas enters one of the chambers, passes through the filter, and exits from the other chamber. The gas is filtered by passage through the permeable wall. The filter tube may be rotated as a unit about a central shaft to move the walls of the cylinder past cleaning means such as scrapers, brushes, vibrators or pressurized gas blasts. The apparatus has special application to the purification of high temperature waste gasses from industrial furnaces.

Abstract: A method of compacting silica dust without the use of water is disclosed. The dust is charged to a hopper and is then injected with air under pressure whereby the weight per unit volume of the material is increased.

Abstract: A gas collection apparatus for use in open electrical smelting furnaces is disclosed. The apparatus comprises an annular body about the outer circumference of the furnace and sealed to the top edge of the furnace on one side thereof with a sloped wall extending into the furnace on the other side to a depth below the normal height of the charge in the furnace.