Abstract: A rotary cutting tool is disclosed which has a tool body, a cutting insert, a clamp member and a clamp screw. The tool body has an insert-receiving recess and a clamp member-receiving aperture formed in an outer surface thereof. The insert-receiving recess has a bottom and at least two bearing walls disposed so as to be inclined with respect to each other. The clamp member-receiving aperture is disposed so as to be communicated with the recess. The cutting insert includes a plate having a front face serving as a rake surface and a rear face. The cutting insert is releasably received in the recess with the rear face being mated with the bottom, in such a manner that the front face is partly located in the clamp member-receiving aperture. The clamp member has an axis therethrough and an engagement portion. The clamp member is releasably accommodated in the clamp member-receiving aperture so as to be axially slidable, with the engagement portion being held in abutment with the front face of the cutting insert.

Abstract: A protective structure for a surge absorber which is composed of the surge absorber, connecting means for connecting the surge absorber to an electronic device and means for protecting the surge absorber as well as the electronic device from fire caused by a continuous overvoltage. The surge absorber protecting means is composed of a first electroconductive spring member which does not deteriorate from heat generated by repeated transient surge voltages to which it might be subjected. This spring member may be connected to a communication line and is movable between a first spring-loaded position wherein it connects the electronic device and the surge absorber to the communication line and a second non-spring loaded condition wherein the connection is broken. Also included are release means for releasing the first member from its first spring-loaded position which release means is activated by heat generated from a continuous overvoltage.

Abstract: A cutter insert for a ball end mill is disclosed which includes a plate-like insert body having a front face and a side face extending from the front face. The front face has a generally convexly curved marginal ridge defined by the intersection of the front face with the side face. The marginal ridge serves as a cutting edge. The front face serves as a rake surface for the cutting edge while the side face serves as a relief surface for the cutting edge. The cutting edge has a leading portion to be indexed in the end cutting position and a trailing portion to be indexed in the peripheral cutting position. A land is formed on the rake surface so as to extend along the cutting edge. The land has a width gradually increasing in a direction from the leading portion of the cutting edge toward the trailing portion thereof.

Abstract: The surge absorber having a surge absorbing element, and first and second wire means for electrically connecting the surge absorbing element across the input lines of an electronic device. The first and second wire means are connected to the surge absorber by conductive heat releasable means, for example, a low melting point solder. The second wire means includes a spring loaded member such that, on release of the first or second wire means by the first or second heat releasable means, respectively, by melting of the solder due to heat generated by the surge absorbing element, the surge absorbing element moves away from the first or second wire means. The surge absorber prevents an abnormal heating of the surge absorbing element when continuous overvoltages or overcurrents pass therethrough.

Abstract: In apparatuses for melting semiconductor material and growing single crystals of semiconductor material, the apparatus comprising:(a) a furnace,(b) a cylindrical double crucible assembly comprising an inner crucible in which single crystals of semiconductor material are grown at a vertical-concentric line thereof, the inner crucible having an upper part and a lower part, and an outer crucible in which melted semiconductor material is received, the outer crucible having the inner crucible disposed therein,(c) a susceptor for supporting the outer crucible,(d) rotating means for rotating the susceptor,(e) a feed pipe for supplying starting material in the space formed between the inner and the outer crucibles,(f) fluid-passage means for permitting the melted semiconductor material to flow between the inner and outer crucibles, the fluid-passage means being disposed at the lower part of the inner crucible, andwherein the inner crucible being set inside the outer crucible in a separable manner, the apparatus impro

Abstract: A corrosion resistant zirconium alloy for use as a nuclear reactor cladding material. This alloy consists essentially of, on a weight % basis 0.02-1.7 % Sn, 0.19-0.6% Fe, 0.07-0.4% Cr, 0.01-0.2% Ta, and optionally 0.05 up to less than 0.5% Nb, the balance being Zr and incidental impurities, provided that the content of the nitrogen in the form of incidental impurities is no more than 60 ppm.

Abstract: A monocrystal rod utilized for producing the semiconductor device or solar cell includes a neck section, a main rod section and a shoulder section. The neck section is smaller in diameter than a seed crystal. The main rod section is formed integrally with the neck section and is larger in diameter than the neck section. The shoulder section is tapered for linking the neck section to the main rod section. The main rod section has a stopper section at the top portion of the main rod section, and the stopper section is larger than the main rod section.Also, an apparatus for preparing the monocrystal rod has a safety member for supporting upward the stopper section of the falling monocrystal rod.Further, a method of preparing the monocrystal rod includes the steps as follows. The seed crystal is pulled out from a melt in a crucible while rotating it.

Abstract: A cutting tool having a positioning block inserted between the cutting insert and the insert-receiving seat is disclosed. The disclosed cutting tool demonstrates excellent resistance to damage by severe vibration caused by the milling process. The cutting tool of the present invention comprises (a) a tool body having a recess formed at a forward end thereof and defining a insert-receiving seat; (b) a cutting insert; (c) a positioning block to be placed between the cutting insert and said insert-receiving seat, having a top and bottom faces and having a hardness thereof which is lower than that of a surface of an insert-receiving seat; and (d) clamp means for securing the cutting insert and the positioning block on the insert-receiving seat. The above described positioning block is able to absorb some extent of vibration of the cutting insert during the milling process. According to the present invention, there is also provided the cutting tool in which a positioning block has two layers.

Abstract: A cutting insert is disclosed which includes a polygonal plate-like insert body defined by a front face, a rear face and a plurality of side faces lying between the front face and the rear face. The insert body has at least one main cutting edge defined by the intersection of the front face with one of the side faces and at least one nose portion intersecting the at least one main cutting edge and defined by one of the corners of the front face. The front face has an inclined surface extending immediately from the nose portion and sloping toward the rear face in a direction away from the nose portion.

Abstract: A method for reducing pressure losses in a cyclone separator includes introducing a gas entraining a particulate material into a duct connected to the cyclone separator, separating at least a portion of the particulate material through an opening formed in a bottom surface of a horizontally extending section of the duct in proximity to a junction point of the duct to the cyclone separator, and introducing the gas entraining the particulate material into the cyclone separator. A ducting system for the cyclone separator includes the duct and the opening. The particulate material is prevented from being deposited and heaped in the vicinity of the junction point.

Abstract: A rotary cutter is disclosed which includes a cutter body having an axis of rotation therethrough and a cutting insert releasably secured to a forward end of the cutter body. The cutting insert has marginal ridges defining a main cutting edge and an auxilliary cutting edge. The main cutting edge is directed radially outwardly of the cutter body while the auxiliary cutting edge is directed axially forwardly of the cutter body. The cutting insert has faces defining a first rake surface and a second rake surface. The first rake surface is disposed adjacent to the main and auxiliary cutting edges such that an axial rake angle is no less than +30.degree.. The second rake surface is disposed between the first rake surface and the auxiliary cutting edge such that an angle, defined between the second rake surface and the axis of rotation of the body as viewed in a cross-section perpendicular to the auxiliary cutting edge, is no larger than .degree.20.degree..

Abstract: A throwaway insert having a generally quadrilateral-shaped flat plate configuration is disclosed that includes first and second major faces disposed parallel and opposite to each other; oppositely facing first and second side faces extending between the first major face and the second major face; remaining oppositely facing third and fourth side faces extending between the first major face and the second major face; major cutting edges, one each constituted along each of the intersections of the first and second major faces with the first and second side faces minor flanks, one each constituted along the intersections of each of the first and second major faces with the third and fourth side faces, the minor flanks extending between a pair of oppositely formed intersections of the first major face with the first and second side faces, and between a pair of the oppositely formed intersections of the second major face with the first and second side faces, where the intersection constitutes the major cutting edg

Abstract: There is disclosed an Al.sub.2 O.sub.3 based ceramic which includes 5% to 50% by weight of a hard dispersed phase of at least one compound selected from metal carbide, metal nitride, metal carbonitride, metal oxy-carbide, metal oxy-nitride and metal carbo-oxy-nitride. The compound is represented by M(CNO), wherein M is at least one metal selected from the group consisting of Ti, Zr and Hf. The ceramic contains no greater than 25% by weight of ZrO.sub.2, and balance Al.sub.2 O.sub.3 matrix. which contains an additive dissolved in the Al.sub.2 O.sub.3 grains so as to form solid solution therewith. The additive is contained in an amount of 0.01% to 12% by weight with respect to the Al.sub.2 O.sub.3 matrix and is at least one oxide of an element selected from the group consisting of Y, Mg, Cr, Ni, Co, and rare earth elements. The Al.sub.2 O.sub.3 grains have an average grain size no larger than 1.0 .mu.m while the hard phase constituent has an average grain size no larger than 0.6 .mu.m.

Abstract: A ball end mill is disclosed which includes a tool body having an axis of rotation therethrough and having a forward end portion, and a cutting edge provided on the forward end portion of the tool body and having an arcuate shape as viewed in a direction opposite to the direction of rotation of the tool body. The cutting edge is comprised of a radially inner portion disposed adjacent to the axis of rotation of the tool body and extending radially inwardly of the tool body in a direction opposite to the direction of rotation of the tool body, and a radially outer portion extending from the inner portion radially outwardly and axially rearwardly of the tool body. Each of the inner and outer portions of the cutting edge is formed of a two-layered composite sintered complex having a base layer of cemented carbide and an upper layer of sintered super hardened compact disposed on the base layer and containing cubic boron nitride, diamond or the like.

Abstract: A microwave absorbing heater comprising a porous body containing silicon oxide and having a porosity of 40 to 95%.A microwave absorbing heater may be formed of a porous body having a porosity of 40 to 95% and composed of an inorganic electrical insulating material, and a silicon carbide film formed on the surface thereof.Since the microwave absorptivity is high, the dissipation of water from a heated object is easy and the heat dissipation is small, the heating efficiency is great. The thermal shock resistance is also high.

Abstract: An end mill is disclosed which includes a tool body having a shaft-like shape. The tool body has a cutting edge portion formed at one end thereof. The cutting edge portion has a plurality of circumferential cutting edges formed on the circumference thereof along the longitudinal axis of the tool body. The end mill is characterized in that the cutting edge portion has the circumferential surface thereof which includes rake faces and flanks. Each of the rake faces adjoins one of two adjacent circumferential cutting edges. Each of the flanks intersects with one of the rake faces at one end and adjoins the other of the two adjacent circumferential cutting edges at the other end. The rake faces have a rake angle arranged between a range of 5.degree. to -45.degree. at a cross section perpendicular to the axis of the tool body. The flanks have a relief angle arranged between a range of 20.degree. to 45.degree. at a cross section perpendicular to the axis of the tool body.

Abstract: An inserted tooth rotary cutter is disclosed which includes a tool body having an axis of rotation therethrough and a plurality of indexable cutting inserts. The tool body is defined by forward and rearward axial faces and a circumferential surface lying between the forward and rearward axial faces. The tool body has a plurality of insert receiving recesses formed in the circumferential surface in circumferentially spaced relation to one another and has a mounting bore formed coaxially therewith. Furthermore, the tool body has a plurality of through holes formed in circumferentially spaced relation to one another. Each through hole is disposed between two adjacent insert receiving recesses and opens to the circumferential surface and the forward axial face. Each insert is releasably secured to a respective insert receiving recess.

Abstract: A microgap type surge absorber comprises a columnar insulator element being covered with a conductive material and provided with a microgap around the center thereof, a pair of conductive caps being fixed on the both ends of the element, first and second electrodes being attached to the both caps, first and second glass tubes adhering to the periphery of the first and second electrodes and surrounding the end parts of the element, and a cylindrical third electrode being held between the both glass tubes and adjacently surrounding the element containing the microgap. The first, second, and third electrodes and glass tubes are charged with inert gas. When a glow discharge started from near the microgap extends to the conductive coating and arrives at the caps, an arc discharge is formed between caps through the third electrode. The third electrode protects the microgap from arc discharge current.

Abstract: A copper smelting process is disclosed in which copper concentrate is smelted in a furnace to produce purified copper. Flue gas discharged from the furnace is treated to produce sulfuric acid. Furthermore, waste liquid discharged during the production of sulfuric acid is treated to produce gypsum, and the gypsum thus produced is recycled to the furnace as a flux. The flue gas may be exhausted from either or both of a smelting furnace and a converting furnace, and the gypsum may be preferably introduced into the converting furnace.

Abstract: Concentrations of cobalt and copper of electrolysis solution for electrowinning of zinc can be measured any time during electrowinning operation by continuously sampling the solution, diluting it, adding coloring reagent to the flow of the solution and spectrophotometrically analyzing the solution.The cobalt and copper as deleterious impurities can be removed continuously and automatically by measuring their concentrations by the above method and adding precipitation reagents for them in an amount calculated by a microcomputer on the basis of said analysis.