Abstract: A portal frame 3 made of wide flange sections without braces is fixed to the external surfaces of an existing RC-column 5 extending in the vertical direction and to the external surfaces of existing RC-beam 8 extending in the horizontal direction of a reinforced concrete building. The wide flange section column 4 fixed to the existing RC-column 5 is assigned a bending rigidity roughly equivalent to that of the existing RC-column 5, thereby reducing the stress additionally occurring at the connecting part between the existing RC-column 5 and column 4 by deforming the column 4 similarly to the existing RC-column 5 under the horizontal load transmitted from existing RC-beam 8 and/or wide flange section beam 6 during an earthquake. Using a steel portal frame without braces preserves the building appearance and avoids bracing which may block windows while increasing earthquake resistance.

Abstract: In a heat-treatment apparatus for heat-treating a V-type cylinder block (W) by induction heating, the block (W) is fixedly mounted on a work table (11) and set at a reference position thereon. A plurality of induction heating coils (23) are disposed in each of opposite sides of a base frame (10) of the work table (11) through Z tables (21), Y tables (18) and X tables (13). These tables (13, 18, 21) enable the heating coils (23) to enter and exit from the corresponding cylinder bores (Wn) of the block (W) in a direction in parallel with a longitudinal direction of the cylinder bores (Wn). The Z table (21) moves back and forth in parallel with the longitudinal direction of the cylinder bores (wn). The Y table moves back and forth in a direction perpendicular to the rows of the cylinder bores (Wn). The X table (13) moves back and forth in parallel with the rows of cylinder bores (Wn).

Abstract: In a method of producing hollow rack bars from steel tubes for use in steering equipment for automobiles and so on, a part of the length of the steel tube to be processed and its adjacent parts is held in split dies that encircle a whole circumference of the tube except for the dies having a hole coinciding with the part of the tube to be processed. Then, a punch is inserted into the hole in a closed state of the dies for flattening a part of the tube, and then mandrels are pushed into the tube for ironing from the inside to form a rack pattern, when a rack forming die is inserted into the hole and held in contact with the flattened part of the tube.

Abstract: In a heat-treatment apparatus for heat-treating a V-type cylinder block (W) by induction heating, the block (W) is fixedly mounted on a work table (11) and set at a reference position thereon. A plurality of induction heating coils (23) are disposed in each of opposite sides of a base frame (10) of the work table (11) through Z tables (21), Y tables (18) and X tables (13). These tables (13, 18, 21) enable the heating coils (23) to enter and exit from the corresponding cylinder bores (Wn) of the block (W) in a direction in parallel with a longitudinal direction of the cylinder bores (Wn). The Z table (21) moves back and forth in parallel with the longitudinal direction of the cylinder bores (wn). The Y table moves back and forth in a direction perpendicular to the rows of the cylinder bores (Wn). The X table (13) moves back and forth in parallel with the rows of cylinder bores (Wn).

Abstract: Hardening is accomplished by heating a longitudinal section of a workpiece such as an odd-shaped bar, and by quenching while constraining the workpiece section in dies. The quenching is executed while the workpiece is pressed in a direction perpendicular to its longitudinal direction by a pressing device which is installed adjacent to the workpiece section constrained in the dies. Warping by quenching can thus be minimized in odd-shaped workpieces, such as an automobile steering rack bar.

Abstract: In the method, apparatus and the substance produced thereby: a plasma flame 1 is produced by a plasma torch 11; the plasma flame 1 is passed through a plasma flame furnace 21 which controls the heat of the plasma flame 1; then, the plasma flame 1 is injected into a reactor column 31 to heat the substance. The substance may be a particle. The plasma flame 1 has a wide flame area in which a temperature of flame is uniform.

Abstract: In the method, apparatus and the substance produced thereby: a plasma flame 1 is produced by a plasma torch 11; the plasma flame 1 is passed through a plasma flame furnace 21 which controls the heat of the plasma flame 1; then, the plasma flame 1 is injected into a reactor column 31 to heat the substance. The substance may be a particle. The plasma flame 1 has a wide flame area in which a temperature of flame is uniform.

Abstract: A method and an installation for producing biconical wire, i.e., wire with repeating cylindrical and conical wire sections from a cylindrical starting material, in particular for producing helical compression springs inexpensively by using hot forming to form the conical wire sections. The installation has a heating unit (1) and a forming unit (2). The embodiment also includes a cooling unit (3) downstream from the heating unit (1), a cooling unit (4) downstream from the forming unit (2), a roll control (5), a re-rolling unit (6) downstream from the forming unit (2), another heating unit (7) for annealing or tempering, a cooling unit (8) downstream from the additional heating unit (7), an uncoiler (9), a roller straightening apparatus (10) and a coiler (11).

Abstract: In the apparatus: Y table 43 carries a work W and travels a predetermined distance in direction Y in a reciprocating manner; X table 41 causes the work W to reciprocate in direction X between a first position, in which the work W is loaded onto and unloaded from Y table 43, and a fourth position, in which an induction heating coil 23 is disposed; X table 41 is mounted on a base frame 11; a first reference on Y table 43 positions rows of quenched portions 76a of the work W in desired locations when the work W is loaded onto Y table 43; a second reference on Y table 43 serves as a reference for determining coordinates of Y table 43; a position measuring means 32 in a second position intermediate between the first and the third position measures coordinates of the second reference and of the quenched portions 76a; and, a control means 100 issues signals to control X-Y table 40 together with the heating coil 23 based on the measured coordinates.

Abstract: A raw material prepared by washing a phosphor powder containing a phosphor host material and an activator with an acid solution, followed by drying the washed powder, is heated within a thermal plasma at a temperature which permits partially melting the phosphor, followed by cooling and subsequently subjecting the resultant phosphor at 1200.degree. to 1700.degree. C., thereby manufacturing spherical phosphor particles having a concentration gradient in a radial direction.

Abstract: This invention provides a method and apparatus for quenching a tubular workpiece such as cylindrical tubes or different-shaped tubes, which are difficult to be exerted constraining force for preventing warping especially in case of thinner thickness. Warping is prevented by applying a constraining force which is increased from beginning of the quenching to termination thereof, corresponding to increase of elasticity limit stress in accordance with temperature drop of the workpiece. Furthermore, apparatus for carrying out the method for quenching a tubular workpiece are offered, wherein the apparatus are provided with a pressure controller for pressure rolls or dies, thereby the pressure controller changes setting input for the pressure during the quenching.

Abstract: A constrained quenching apparatus is provided for hardening a workpiece such as an asymmetrical bar which has a notable tendency to warping when quenched, without warping the workpiece. The apparatus comprises a set of two or more dies having plural projections provided on the inner side thereof, the projections coinciding with the contour of the workpiece when the dies are closed so that their die faces in contact with one another, and having plural recesses therein defined by the projections. The recesses are provided with one or more cooling liquid blow holes. The apparatus does not exert pressure on the workpiece at the start of the quenching when the workpiece is soft, so the flattening of the hollow workpiece such as a pipe, can be prevented.

Abstract: An induction heating coil for forming a hardened layer in the inner wall of an external cylindrical member to be heated is disclosed. On the inner wall of the conductive induction member, a plurality of recess portions are formed at predetermined spaces circumferentially. The portions of the inner wall of the external cylindrical member to be heated which are opposed to the recess portions can be separately heated, in order collectively to form a plurality of separate partial hardened layers in the inner wall of the external cylindrical member to be heated circumferentially.

Abstract: A cutting method to be applied to producing helical springs by cold-forming a thick high-strength wire having a tensile strength in the range of 1765 to 2157 N/mm.sup.2 and a diameter in the range of 8 to 16 mm on a coiling machine, and then the wire is cut at the end coil of the coiled portion to provide a helical spring. A predetermined range about a position on the wire at a distance coresponding to the length of wire in the helical spring from the free end of the wire fed to the coiling machine is heated to a temperature within a predetermined temperature range. Therefore, the end coil of the helical spring is formed by the heated portion of the wire, and hence the helical spring is cut off the wire at a position in the heated portion.

Abstract: An ignition element for use in igniting a high-frequency plasma torch is ungrounded and displaceable. When a tip end of the ignition element is positioned in a location in a gas to be formed into a plasma, which flows under normal pressure, and a high-frequency energy is applied to the above location in the gas flow, the gas is ignited into a high-temperature plasma in a small period of time shorter than 1 second. After the gas has been ignited, the ignition element is immediately retracted out of the location. The ignition element may be in the form of an ignition rod of metal or an ignition tube of quartz or the like. Where the ignition rod is used, it instantaneously contacts the high-temperature plasma upon ignition so that the high-temperature plasma is of high purity consisting only of the component of the gas. The ignition tube may be used for producing a high-temperature plasma of higher purity on and after ignition. The ignition tube is employed while a pressure therein is reduced.

Abstract: A method of starting a current-fed inverter used as a high-frequency induction heating power supply and having a DC cut-off capacitor in the load circuit first supplies successive gate pulses which are spaced apart by small periods of time to a pair of thyristors of a power inverter unit until a turn-on current for the thyristors exceeds a latching current. When a voltage between output terminals of the power inverter unit reaches a predetermined thyristor reverse-biasing voltage, the successive gate pulses are no longer supplied to the thyristor pair. Then, successive gate pulses are supplied to a another pair of thyristors of the power inverter unit. The foregoing operation is repeated for successive thyristor pairs in a predetermined order until the period of oscillation of successive gate pulses supplied to the thyristor pairs is progressively shortened into conformity with a prescribed inverter oscillation period.

Abstract: Apparatus and method for forming a reinforcing cage for a prestressed concrete pile, in which the cage includes a set of main steel bars arranged in a circular pattern and an auxiliary wire which is helically wound around and welded at its crossings with the steel bars, that prevents any crossings from being welded when the current for welding is either insufficient in magnitude or not present and that prevents any unwelded crossings from being subsequently tempered.

Abstract: A flexible bar reinforced concrete pile is provided herein composed of a steel tube containing therein a plurality of jointless high-strength flexible bars, strands or bundles of bar or strand located axially along the inside wall of said steel tube, the remaining space within the steel tube being packed with prepacked concrete or mortar, and a method for constructing the same.