Patents Assigned to Institute po Metaloznanie i Technologia na Metalite
  • Patent number: 4669087
    Abstract: Control system for electroslag remelting having a block for recording arc discharges, the input of which is connected to the current-carrying bus bar of a crystallization mold, while its output is connected to a block for switching over the rate of electrode feed, to the second input of which there is connected the output of a presetting block, and the output of the block for switching over the rate of feed of the electrode is connected via a regulator to an actuating mechanism. The current-carrying bus bar is connected to a block for recording the rectifier valve effect, the output of which is connected via a block for operation switch-over to a third input of the block for switching-over the rate of electrode feed.
    Type: Grant
    Filed: December 8, 1983
    Date of Patent: May 26, 1987
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Ivanka A. Rasheva, Lyudmil K. Valkov, Tzolo V. Rashev, Stoyan M. Stoyanov
  • Patent number: 4635460
    Abstract: Method of plastically deforming a body of malleable solid material between male and female dies which are forcible pressed together. The material is subjected to repeated identical pressing cycles; in each pressing cycle the force between the dies is concentrated consecutively on separate sections of the surface of the material being deformed. The body may be directly or indirectly extruded into an elongated shape from a location between the male and female dies which is disposed nearest the section of the surface of the material being deformed in each pressing cycle, or it may be deformed between the dies without any appreciable portion thereof escaping from between the dies.
    Type: Grant
    Filed: April 29, 1985
    Date of Patent: January 13, 1987
    Assignee: Institute Po Metaloznanie I Technologia Na Metalite
    Inventors: Boyan I. Paunov, Teodor A. Balevski, Bojidar S. Ivanov
  • Patent number: 4616808
    Abstract: A method in which the melt is first treated with solid alloying additives and an alloying gas, and then the casting operation is effected. There is produced a differential between the pressures in the space for additional saturation with alloying gas and in the space where the casting takes place.An apparatus for practicing the above method comprising an induction furnace in a first hermetic chamber, and a second hermetic chamber inside which there is mounted a casting mold. The induction furnace and the first hermetic chamber are interconnected with the second hermetic chamber via a movable launder. Above the one end of the movable launder there is mounted a siphon, underneath its other end there is disposed an tundish, which is mounted inside the first hermetic chamber and is gas-tightly sealed against a separating plate, attached to the second hermetic chamber containing the casting mold. The tundish is provided with a bottom for blowing-through with alloying gas.
    Type: Grant
    Filed: February 4, 1985
    Date of Patent: October 14, 1986
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Ivan D. Nikolov, deceased, by Vassilka P. Dimova, heir, Dobromir I. Dimov, heir, Petar I. Dimov, heir, Marin I. Marinov, Ivan M. Peytchev, Tzolo V. Rashev, Iliya G. Tchorbov
  • Patent number: 4583673
    Abstract: Apparatus for soldering the winding to the commutator of a rotor of great weight of an electric machine. The apparatus has a vessel containing a bath of molten solder and electric resistance heaters, a single-phase magneto-hydrodynamic pump consisting of a first magnetic core disposed beneath the vessel, the first magnetic core being supported from below and surrounded by a winding and solder stream-formation unit made of ferro magnetic material which is concentric with the first magnetic core. The bottom wall of the vessel is disposed on the first magnetic core, and within the vessel and on the bottom thereof there is fastened rigidly an additional, second hollow magnetic core, which is a continuation of the first magnetic core, while a tubular casing which is concentric with the second magnetic core, and which is of stepped shape, seats with its external step on the additional, second hollow magnetic core.
    Type: Grant
    Filed: December 10, 1984
    Date of Patent: April 22, 1986
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Pavel M. Mintchev, Mihail H. Angelov, Hristomir D. Hristov, Stoimen S. Balinov, Nikolay V. Yordanov
  • Patent number: 4550763
    Abstract: A pressure die casting method and apparatus wherein the delivery tube from the melt reservoir contained in the pressurizable housing can receive the melt on the tube affixed to the mold which also is in a pressurizable housing and when the latter tube is retracted from the former, a sliding shutter closes the top of the reservoir tube. Gas communication between the upper end of the reservoir tube and the interior of the housing is permitted to ensure that a gas layer corresponding to that in the housing will overlie the melt in the reservoir portion of the tube.
    Type: Grant
    Filed: December 2, 1981
    Date of Patent: November 5, 1985
    Assignee: Institute po Metaloznanie I Technologia na Metalite
    Inventor: Ivan D. Nikolov
  • Patent number: 4545252
    Abstract: The apparatus comprises a base and two movable opposite centers, one of which is fastened to a rotatable axle, while the other is fastened to a screw by means of a bearing, and mounted in two opposite parallel plates. Between the plates there is disposed a tank filled with an acoustic medium, and underneath it there is mounted a sensor which is connected to a measuring system. Two parallel guides are transversely fastened to the plates. The base is suspended on the parallel guides with a collar fastened to it. The base is provided with a driving screw and a handle. A spring, within the collar and attached to it, is fastened rigidly to a guiding sleeve. To this sleeve there is fastened the tank, on which there are seated parallel rotating rollers. A limiting sleeve of the sensor is mounted inside a guide by means of a locking nut, which is pressed against a second nut fastened to the guiding sleeve.
    Type: Grant
    Filed: September 6, 1983
    Date of Patent: October 8, 1985
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Mihail T. Marinov, Lyubomir T. Petkanchin, Georgi I. Pushev, Georgi T. Kostov, Mitko M. Mihovski, Valentina A. Manolova
  • Patent number: 4523708
    Abstract: An apparatus for soldering the wires of the rotor winding of an electric machine to its commutator. The apparatus comprises a tank with molten solder and heaters, a magneto-hydrodynamic pump for the solder, a device for holding the rotor, and a device for the protection of the molten solder from oxidation. The device for holding the rotor comprises a base in the shape of a hollow cylinder with holes and having a chamfered bottom part of the internal surface thereof in which there is movable disposed a replacement nozzle, which is made up of a sleeve and a rotor holding case rigidly connecting together. The nozzle reciprocates in the base. The commutator of the rotor to be solder is inserted into the case. Between the sleeve and the case there is formed a ring-shaped duct, connected with a booster zone which directs the molten solder toward the commutator.
    Type: Grant
    Filed: May 19, 1983
    Date of Patent: June 18, 1985
    Assignee: Institute Po Metaloznanie I Technologia Na Metalite
    Inventors: Pavel M. Minchev, Hristomir D. Hristov, Stoimen S. Balinov, Mihail H. Angelov, Nikolay V. Yordanov
  • Patent number: 4471640
    Abstract: A machine for the explosive forming of a workpiece of sheet material comprises a yoke-shaped frame with a base carrying a pressure cylinder whose piston is insertable from below into any of several cutouts in an overlying turntable in which dies with cavities spanned by respective workpieces are receivable. An overhanging arm of the frame supports a plate with a bottom recess confronting the cavity of an aligned die and has an upwardly extending supply channel closable by a sliding gate. In operation, with a workpiece clamped between the die and the plate, a force-transmitting medium is admitted into the recess and, with the sliding gate open, a charge provided with a detonation retarder is introduced through the channel with the aid of an igniter at the lower end of that piston which initiates its detonation, occurring after the piston has been withdrawn from the channel and the gate has been closed.
    Type: Grant
    Filed: July 9, 1982
    Date of Patent: September 18, 1984
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Hristo G. Kortenski, Stefan B. Vodenicharov
  • Patent number: 4393916
    Abstract: The invention relates to an apparatus for pressure die casting of metals and alloys involving the action of increased gas pressure on the solidifying melt. In this apparatus, the gas is pressurized automatically during the stroke of the press and pressurized gas at elevated pressure is applied to molten metal in the die cavity immediately after the closing of the die. For this purpose, the apparatus comprises a hydraulic press including a cylinder and a piston slidably mounted therein, which piston divides the cylinder into a first and second chamber. The first chamber is in communication with a source of pressurized liquid and the second chamber is in communication with a gas retaining cavity disposed in the piston rod of the piston. A press plate and die having at least one die cavity is rigidly mounted on the piston rod. The cavity of the die is connected by means of corresponding valves to a supply reservoir with gas under low pressure.
    Type: Grant
    Filed: April 2, 1981
    Date of Patent: July 19, 1983
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Stancho H. Vutov, Rashko R. Slavov
  • Patent number: 4375270
    Abstract: Apparatus for soldering the winding of armatures of electrical machines to the collectors thereof. The apparatus includes a device for gripping, displacing and fixing the armature with the collector, a single-phase magnetic-hydrodynamic pump with metal conduit and a bath with molten solder and heaters. The magnetic core of the single-phase magnetic-hydrodynamic pump is embraced by a metal conduit disposed underneath the bottom of the bath, and the inlet of the metal conduit is connected to the bottom of the bath, while its outlet end is rigidly connected to a casing fastened to the bottom of the bath. To the bottom of the casing there is pressed by means of an easily releasable joint a changeable nozzle unit. When it is necessary to solder a collector with a diameter different from the previous one, the changeable nozzle unit is taken out of the apparatus and new one of a size corresponding to that of the collector to be soldered is inserted in the apparatus.
    Type: Grant
    Filed: January 19, 1981
    Date of Patent: March 1, 1983
    Assignee: Institute Po Metaloznanie I Technologia NA Metalite
    Inventors: Pavel M. Minchev, Hristomir D. Hristov, Stoimen S. Balinov, Nikolay V. Yordanov
  • Patent number: 4331279
    Abstract: Apparatus for soldering the wires of the coil on the armature of an electric machine to the commutator thereof. The apparatus has a device for clamping, shifting and fixing the armature, a monophase magnet-hydrodynamic pump with a charger and a pan with molten solder. The magnetic core of the pump has the shape of a hollow cylinder and is externally chamfered at its upper end. The armature to be soldered is disposed vertically with the lower portion of its commutator telescoped within the upper end of the core. Around the core within the pan there is an annular charger disposed coaxially of the core, the charger having its lower end above the bottom of the pan and its upper end on the level of the upper chamfered end of the core so as to form between the upper end of the charger and the upper chamfered end of the core an annular frusto-conical channel with a discharge end directed toward the upper portion of the commutator and the parts of the wires adjacent thereto to solder the wires to the commutator.
    Type: Grant
    Filed: June 30, 1980
    Date of Patent: May 25, 1982
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Pavel M. Minchev, Hristomir D. Hristov, Stoyan R. Lazarov, Stoimen S. Balinov, Nikolay V. Yordanov
  • Patent number: 4315726
    Abstract: A molding apparatus in which a slider is slidable in an inclined channel into which a passage opens at one side for communication with a mold cavity while a pair of passages open at the opposite side for communication with a plasticating (worm) cylinder and a further cylinder provided with a plunger or piston. The slider has a U-shaped passage, the arms of which are positioned to interconnect both of the passages on the other side of the channel in a position of the slider in which the passage to the mold is blocked but which connects only the accumulating cylinder passage through the bight of the U-shaped passage to the mold in another position of the slider. A check valve is provided in the passage of the worm cylinder.
    Type: Grant
    Filed: April 30, 1980
    Date of Patent: February 16, 1982
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Stefan G. Semerdjiev, Nikolay T. Popov
  • Patent number: 4307263
    Abstract: An electroslag-furnace electrode balancing system in which a pair of double-acting cylinders is connected by a flexible cable passing over pulleys mounted on the electrode carrier, the cylinders being selectively connected to ambient and furnace pressure so that the applied gas pressure balances the pressures to which the electrode may be subject in the furnace.
    Type: Grant
    Filed: October 12, 1978
    Date of Patent: December 22, 1981
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Tzolo V. Rashev, Ivanka A. Rasheva, Konstantin S. Milchev, Yordan G. Lambev
  • Patent number: 4253868
    Abstract: An apparatus for nitriding metal materials and ferroalloys under pressure in which a melting furnace is positioned above a pulverizing chamber and connected thereto, with an intake chamber, provided with a pulverizer, disposed in between with a dust-catching cyclone having a suction collector being connected to the upper portion of the pulverizing chamber. An exchange hopper is connected to an outlet formed in the lower portion of the pulverizing chamber and feeds into an inlet end of a pipe furnace which in turn, feeds into an intermediate hopper. An end hopper is positioned beneath the intermediate hopper and connected thereto and feeds into a briquetting installation. Separate pipe conduit systems are connected to the various elements of the apparatus for supplying pressurized nitrogen thereto or for the evacuation thereof.
    Type: Grant
    Filed: February 26, 1979
    Date of Patent: March 3, 1981
    Assignee: Institute po Metaloznanie I Technologia Na Metalite
    Inventors: Ivan D. Nikolov, Tzolo V. Rashev, Iliya G. Chorbov, Ivan M. Peychev, Hristo G. Penchev, Marin I. Marinov, Alexander K. Bradvarov
  • Patent number: 4227033
    Abstract: An induction crucible furnace for the smelting of materials comprises a crucible which is surrounded by the induction coils and yoke which are mounted upon an intermediate vessel or shell closed by a cover overlying a mass of insulating material interposed between the crucible and inductor and the shell. The intermediate shell has an outwardly extending support flange by which it is mounted on an outward flange of the outer housing with clearance, the clearance likewise being filled with insulating material through openings formed in the flange of the intermediate shell inwardly of the wall of the housing. The flange of the latter projects beyond the flange of the intermediate member and a cover is connected to the housing flange to hermetically seal the system.
    Type: Grant
    Filed: February 27, 1979
    Date of Patent: October 7, 1980
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Ivan D. Nikolov, Pavel M. Minchev, Marin A. Dimitrov, Assen P. Georgiev, Iliya G. Chorbov
  • Patent number: 4116683
    Abstract: A nickel-free corrosion-resistant steel which consists by weight of:Carbon .ltoreq. 0.08%Silicon .ltoreq. 0.9%Chromium = 18.05 to 22%Manganese = 6.0 to 10.5%Nitrogen = 0.40 to 1.10%Sulfur .ltoreq. 0.025%Phosphorus .ltoreq. 0.035%Copper .ltoreq. 3% and the remainder iron.
    Type: Grant
    Filed: April 25, 1977
    Date of Patent: September 26, 1978
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Ivan Dimov Nikolov, Tzolo Valkov Rashev, Rangel Petrov Ivanov, Chavdar Andreev Andreev
  • Patent number: 4092385
    Abstract: A method of injection molding foamed articles wherein, after the mold is closed and while the mold is held closed, a gas counterpressure is generated within the mold cavity against which a portion of the foamable resin is injected under a pressure which prevents foaming. Thereafter, a shape-forming element adapted to be retracted to be flush with a wall of the mold cavity in the final phase thereof, is advanced to force the nonfoamed material, still against the gas counterpressure, into the remainder of the cavity. After a skin has formed, on the mass within the mold cavity the latter element is retracted to permit foaming, preferably after foaming has been initiated by allowing a portion of the foamable mass to recede into the injection cylinder during the inception of the foaming process.
    Type: Grant
    Filed: November 24, 1975
    Date of Patent: May 30, 1978
    Assignee: Institute Po Metaloznanie I Technologia Na Metalite
    Inventors: Angel Tonchev Balevski, Ivan Dimov Nikolov, Evgeni Hristov Mateev, Todor Kostadinov Trifonov, Vassil Vladimirov Kojuharov
  • Patent number: 4090837
    Abstract: An injection molding machine in which a support on a base carries oppositely facing stationary mold portions which, when joined by movable mold portions, form a pair of mold cavities, one of which can be injected with a moldable material having a long solidification time, while the other contains a previously injected article which is solidifying and can be released as soon as the injection of the first cavity is completed. One of the movable mold portions is connected to a movable plate in a fixed spaced relationship, with a wedge-type locking mechanism between the plate and the other movable mold portion for the locking of both mold cavities simultaneously with a single locking mechanism.
    Type: Grant
    Filed: January 19, 1977
    Date of Patent: May 23, 1978
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Angel Tonchev Balevski, Ivan Dimov Nikolov, Dragan Iliev Nenov
  • Patent number: 4050503
    Abstract: An apparatus for casting a molten material in which the mold is received in one chamber and the molten material is received in another chamber, the two chambers being subject to different pressures so that a tube connecting them can deliver the molten material from the second chamber to the first under a pressure differential. Signal-producing apparatus connected to the mold chambers produce signals representing the two pressures and the pressure differential, the signal-producing apparatus being connected to differentiating apparatus whose output produces time derivatives of the pressures and pressure differential. The time derivatives can be used to control the pressures via a comparator to which a reference value or set point signal is applied thereby varying the rate of filling of the mold in accordance with a predetermined program.
    Type: Grant
    Filed: January 23, 1976
    Date of Patent: September 27, 1977
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Angel Tonchev Balevski, Ivan Dimov Nikolov, Dragan Iliev Nenov, Emil Nikolov Momchilov
  • Patent number: 3949905
    Abstract: An apparatus for the production of articles with a compact smooth skin and a cellular core from polymer materials, which contain blowing agents, by injection molding or extrusion wherein the apparatus contains an electric heating element within a channel through which the polymeric material is passed.
    Type: Grant
    Filed: June 5, 1974
    Date of Patent: April 13, 1976
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Ivan Dimov Nikolov, Stefan Georgiev Semerdjiev, Dragan Iliev Nenov, Nikolay Tihomirov Popov