Abstract: A dome shaped ceramic insert which defines a portion of a swirl chamber is formed at the crown portion with a single aperture through which both the fuel injector and the glow plug can extend. The cylinder head is formed with a portion which fits into the aperture and which has a wall portion which cooperates with the inner walls of the insert to define the upper section of the swirl chamber.

Abstract: In preparing a resin coated sand for use in sand mold casting processes by a hot-melt process using an unsaturated polyester which is solid at room temperature as the coating material, a solution of an organic peroxide as a polymerization initiator for the unsaturated polyester is introduced into the mixture of heated foundary sand and the unsaturated polyester while the polyester is in the state of liquid coating on the sand particles, and stirring is continued to uniformly mix the solution with the unsaturated polyester and evaporate and dissipate the solvent before solidification of the polyester coating as the result of cooling of the mixture. The polyester coating contains no liquid cross-linking agent, so that the resin coated sand is untacky and high in fluidity at room temperature and, therefore, can be filled into a die cavity to shape a sand mold or core with sufficiently high bulk density.

Abstract: A method of producing a large-sized body of a ceramic honeycomb structure, comprising the steps of integrating unfired unit blocks each having a prismatic shape and a honeycomb structure with axial gas passages into a large-sized body by bonding the unit blocks to one another with a bonding agent and firing this body. The unit blocks are formed of a ceramic composition consisting of a powdered ceramic material and completely gasifiable substances, and essential components of the bonding agent are also completely gasifiable substances such as a combination of an organic binder material used in the ceramic composition and a solvent for this binder material. The gasifiable substances present in the large-sized body are completely dissipated by heating before the occurrence of sintering of the ceramic material by firing, so that the fired product is a wholly and homogeneously ceramic body of a honeycomb structure highly resistant to thermal shocks.

Abstract: An axial flow inducer for hydraulic devices is disclosed. The inducer is coaxially arranged in front of a fluid suction inlet side of a main impeller of an hydraulic device, for example, a pump and constituted by at least two axial flow blade parts which are constructed and arranged so as to prevent an occurrence of noise over all flow amount region of the impeller.

Abstract: A high temperature abrasion-resistant material in the form of a sintered mass such as a board consists of NiO and/or CoO, Ni and/or Co, and a solid lubricant such as CaF.sub.2. The concentration of the total oxide in the mass is maximum at the surface and continuously decreases as the depth from the surface increases, but the concentration of the total metal is substantially zero at the surface and continuously increases as the depth increases. The lubricant is uniformly distributed. This material is produced by firstly sintering a powder mixture of the ingredients in a non-oxidizing atmosphere into a mass of a desired shape and subsequently heating the sintered mass in an oxidizing atmosphere.

Abstract: A low wear coating formed on a metal substrate to serve as a high temperature rubbing seal layer, comprising a surface layer made fundamentally of a wear resistant metal oxide such as nickel oxide and a solid lubricating material such as calcium fluoride and at least one intermediate layer made fundamentally of the metal oxide optionally with the addition of the lubricating material, wherein at least an outmost intermediate layer as well as an inmost region of the surface layer is impregnated with a brazing solder. The solder is added in the form of powder to the material of the intermediate layer prior to a flame spraying process and later caused to melt and permeate into the surface layer formed by flame spraying.

Abstract: A member including a metal substrate, a low wear coating formed by flame spraying a mixture of a wear resistant metal oxide such as nickel oxide and a solid lubricating material such as calcium fluoride to serve as a high temperature rubbing contact seal layer and at least one undercoat layer formed by flame spraying between the substrate and the surface layer, characterized by the presence of a metal in at least one of the undercoat layers mixed with a commonly employed fundamental material, which is the wear resistant metal oxide optionally with the addition of the solid lubricating material, in order to lessen the difference in thermal expansion coefficient between the individual undercoat layer and the surface layer.