Abstract: The toy flute is configured such that: a reciprocating body is accommodated inside a cylindrical body in a reciprocating manner; the cylindrical body is installed at an inner side of an opening section provided at a hollow body in such a manner that a vent hole at one side from among two vent holes provided at the abovementioned cylindrical body can communicate with the abovementioned opening section; and a flute section is installed at the abovementioned cylindrical body in such a manner that airflow flowing between the abovementioned opening section and a vent hole at the other side from among the abovementioned two vent holes causes sound to occur and reverberate inside the cylindrical body.

Abstract: An iron-based sintered alloy having improved thermal and mechanical strength is provided. The iron-based sintered alloy with dispersed hard particles comprises: a matrix comprising, by weight, 0.4 to 2% silicon (Si), 2 to 12% nickel (Ni), 3 to 12% molybdenum (Mo), 0.5 to 5% chromium (Cr), 0.6 to 4% vanadium (V), 0.1 to 3% niobium (Nb), 0.5 to 2% carbon (C), and the reminder of iron (Fe); and hard particles comprising 60 to 70% molybdenum (Mo), 0.3 to 1% boron (B), 0.1% or less carbon (C), and the reminder of iron (Fe). The hard particles are dispersed in the matrix in an amount in the range of 3 to 20% based on the entire alloy. They are sintered to produce the iron-based sintered alloy. Addition of boron into the ferromolybdenum hard particles enhances the wettability of the ferromolybdenum hard particles to prevent the hard particles from falling off the matrix.

Abstract: A side rail is formed into a ring shape having its generally rectangular section that has an outer surface 3 formed with a pair of edge surfaces 5 of small radius, and an intermediate surface 6 of large radius of curvature formed between the edge surfaces 5. When the side rail is in the inclined condition in operation, each edge surface 5 can easily ride on oil film on cylinder 16 and allow the side rail 1 to perform smooth sliding movement on the inner surface of cylinder. The intermediate surface 6 efficiently scrapes lubricating oil on cylinder to form lubricating oil film of necessary and minimum thickness between an inner surface 17 of cylinder 16 and side rail 1. Also, the larger radius of curvature for forming the intermediate surface 6 provides a larger contact area to the inner surface 17 of cylinder 16 to improve wear resistance.

Abstract: A two piece oil control ring is provided which comprises a ring body (1) formed into a generally M- or I-shaped section with an annular groove (4) on an inside surface (3) of the ring body (1); and a coiled expander (2) attached in the annular groove (4) of the ring body (1) for resiliently urging the ring body (1) toward an inner wall of a cylinder. The ring body (1) is made of stainless steel that contains chromium of 3.0 to 13.0 weight % with the outer and inner circumferential surfaces (11, 12) covered with nitrided layers (14, 15). Circular ratio (&tgr;) of an outer edge length (Yo) to an inner edge length (Yi) in the cross section of the ring body (1) is in a range between 1.08 and 1.32 to keep precise peripheral circularity of the ring body so that the nitrided layers survive lapping of the ring body (14, 15).

Abstract: A scale formation-inhibitory agent used in a welding treatment comprises a polymer selected from the group consisting of polymers having oxygen atoms in the main chain and polymers capable of being thermally depolymerized. The scale formation-inhibitory agent can inhibit the formation of scale on the surface of a metal part to be welded during a welding treatment.

Abstract: The oil control ring 1 is provided to attach in an annular groove 10 formed in a piston 2 for internal combustion engine. The spacer expander 4 comprises a base 8, a plurality of supports 6 and a plurality of arms 7. The supports 6 and arms 7 are integrally formed with the base 8 to extend from an outer periphery 8a or inner periphery 8b of the base 8. The supports 6 resiliently urge a side rail 5 mounted on the space expander 4 toward an upper surface 14 of the annular groove 10 so that during upward stroke of the piston 2, the supports 6 can be resiliently deformed to form between the side rail 5 and upper surface 14 of the groove 10 a radial passage through which oil scraped by the side rail can be drained. Each arm 7 is provided with a lug 8 to resiliently urge the side rail 5 in radial and outward direction.

Abstract: In a shoe 5 for a swash plate compressor, the conical tapered surface 13 is formed between the spherical surface 10 and the rounded edge 14 to converge toward the spherical surface 10 inside an imaginary spherical surface 15 including the spherical surface 10. The conical tapered surface 13 forms a relatively large arcuate gap 23 between the hemispherical concavity 7 and the conical tapered surface 13. The arcuate gap 23 serves to reserve necessary amount of lubricant oil which may be supplied to sliding portions between the spherical surface 10 of the convex surface 11 and hemispherical concavity 7 of the piston 2. In addition, upon manufacture of the shoe 5, it can easily be removed from a metallic mold 52 due to existence of the arcuate gap 23 which prevents tight fit of the shoe 5 in the mold 52.

Abstract: A method and a detector for detecting nitrogen oxide in test gas are provided wherein test gas which contains NOx and interference gases is supplied through an oxygen feeder 4 into a measuring chamber 1a, and the interference gases are oxidized by oxygen or oxygen ion supplied to the measuring chamber 1a through oxygen feeder 4. A total amount of NOx in the test gas is detected based on a level of EMF produced between a first electrode 2 for detecting oxygen and NO2 gas and a second electrode 3 for detecting oxygen.

Abstract: An iron base sintered alloy with dispersed hard particles is provided which comprises by weight 3 to 15% nickel (Ni), 0.5 to 5% chromium (Cr), 0.5 to 2.0% carbon (C), the remainder iron (Fe) and unavoidable impurities. At least a part of nickel (Ni), molybdenum (Mo) and chromium (Cr) is contained in solid solution of an iron base matrix. At least a part of molybdenum (Mo) and chromium (Cr) is dispersed within the iron base matrix to form fine carbides or intermetallic compounds thereof. Uniformly dispersed within the iron base matrix are hard particles of 3 to 20% contain 50 to 57% chromium (Cr), 18 to 22% molybdenum (Mo), 8 to 12% cobalt (Co), 0.1 to 1.4% carbon (C), 0.8 to 1.3% silicon (Si) and the remainder iron (Fe) to strengthen the dispersion and remarkably improve wear resistance.

Abstract: A pipe coupling is provided having a pair of arcuate housings each provided with a crescent groove and a crescent protrusion formed on an abutting end surface of the arcuate housings in the positions which is symmetrical to each other around a vertical axis and is offset from a transverse central axis. When the arcuate housings are tightened by bolts and nuts, the crescent protrusion is inserted into the crescent groove, thereby causing skewed movement of the arcuate housings around the vertical central axis of the pipe coupling in adverse directions to the predetermined angular positions. Thus, upon completion of tightening by the bolts, excessive tightening by the bolt is prevented due to mutual contact of the abutting end surfaces of the arcuate housings.

Abstract: A joint structure, constituting a camshaft, of a metallic tubular member and metallic annular cam defining parts, the annular parts being joined to the outer periphery of the tubular member. Each of the annular parts has around its inner periphery at least one serrated portion which cuts into the outer periphery of the tubular member when they are joined, the annular part also having a planar portion facing another portion of the tubular member in such a manner that substantially no pressure is exerted on the planar portion of the annular part.

Abstract: A joint structure of a metallic tubular member and metallic annular parts, the annular parts being joined to the outer periphery of the tubular member as in a camshaft. Each of the annular parts has around its inner periphery at least one serrated portion which cuts into the outer periphery of the tubular member when they are joined, the annular part also having a planar portion facing another portion of the tubular member in such a manner that substantially no pressure is exerted on the planar portion of the annular part.A method of making such structure involves positioning of the tubular member is required in relation to the annular parts, as by use of a split die, and then forcing into the tubular member a pressing member to expand the tubular member so that the serrated portions cut into the outer periphery of the tubular member.

Abstract: An improved electrical heating molded-element or unit in which a heating wire is embedded or confined in one side of a fibrous layer formed by molding inorganic fibers into a given thickness, characterized in that a portion of said element or unit in the vicinity of the embedded heating wire is treated to provide a zone in which the density, heat conductivity and fire resistance are greater than those of the remainder. With this electrical heating molded-element or unit, it is possible to extract effectively the amount of heat generated by heating wire. This element or unit can be used over an extended period of time with safety but without causing local disintegration thereof owing to the expansion or contraction of the heating wire.

Abstract: A method of producing an insert for the combustion chamber of a diesel engine having an oblique injection port comprising inserting a cylindrical work blank into a die, then cold- or hot-compressing such cylindrical work blank between a punch and counter-punch to form a compressed center-recessed shape, forming an oblique recess in at least one side of the bottom of the center recess of said shape at such an end position as to correspond to the injection port to be formed, and then developing a hole in said oblique recess in conformity with the configuration and extent thereof.

Abstract: A sliding member having a coating especially suitable for a piston ring or a cylinder liner in which excellent wear- and scuff-resistance, as well as excellent initial wear-in property are required. The coating is produced by plasma-arc flame spraying a mixed powder comprising molybdenum powder, nickel-chromium alloy powder and titanium carbide powder on a base surface of the sliding member made of iron or steel.

Abstract: A novel group of iron-base sintered alloys especially suitable for valve seat manufacture having excellent wear resistance and good machinability is provided. The alloy is produced by a combination of specific atomized pre-alloyed powder, iron powder and graphite powder by compacting and sintering processes. Various manufacturing methods with or without infiltration of filler materials into pores in the sintered product to improve wear resistance and machinability are disclosed.