Abstract: In a method of detecting defects generated in a honeycomb structural body, both end sections of the honeycomb structural body is sealed along a flowing direction of exhaust gas. Air is supplied in the flowing direction of the exhaust gas from one end section to the other end section of the honeycomb structural body. Microphones are arranged at outer periphery of the honeycomb structural body and detect sounds of air leaking from a skin layer of the honeycomb structural body. A judgment step judges whether or not defects such as holes having not less than a predetermined diameter and cracks are generated on the basis of a magnitude of the detected sounds of the leaking air.

Abstract: In a method of detecting defects generated in a honeycomb structural body, both end sections of the honeycomb structural body is sealed along a flowing direction of exhaust gas. Air is supplied in the flowing direction of the exhaust gas from one end section to the other end section of the honeycomb structural body. Microphones are arranged at outer periphery of the honeycomb structural body and detect sounds of air leaking from a skin layer of the honeycomb structural body. A judgment step judges whether or not defects such as holes having not less than a predetermined diameter and cracks are generated on the basis of a magnitude of the detected sounds of the leaking air.

Abstract: The spark plug manufacturing apparatus includes a holding plate formed with a plurality of mounting holes penetrating from a front surface to a rear surface thereof for holding therein hollow tubular insulators of spark plugs, each of which is fitted therein with a center electrode and a metal stem provided with a terminal part, and is charged with a powder resistance material between the center electrode and the stem, and an electric furnace for heating the insulators held in the mounting holes of the holding plate. The holding plate is made of a ceramic material containing not less than 50 wt % of silicon nitride.

Abstract: The spark plug manufacturing apparatus includes a holding plate formed with a plurality of mounting holes penetrating from a front surface to a rear surface thereof for holding therein hollow tubular insulators of spark plugs, each of which is fitted therein with a center electrode and a metal stem provided with a terminal part, and is charged with a powder resistance material between the center electrode and the stem, and an electric furnace for heating the insulators held in the mounting holes of the holding plate. The holding plate is made of a ceramic material containing not less than 50 wt % of silicon nitride.

Abstract: A deodorant fibrous material contains (1) as a first deodorant material, at least one deodorant component selected from inorganic type and polyorganic acid, ester or salt type components, (2) as a second deodorant material, at least one hydrazine compound and (3) a synthetic resin binder. The deodorant fibrous material can be produced by applying to a fibrous material by a padding or coating method, a liquid composition containing the above components (1)-(3), followed by subsequent heat treatment.

Abstract: A deodorant fibrous material contains (1), as a first deodorant material, at least one deodorant component selected from inorganic type and polyorganic acid, ester or salt type components, (2), as a second deodorant material, at least one of a hydrazine compound and a specified polyvinyl amine compound and (3) a synthetic resin binder. The deodorant fibrous material can be produced by applying to a fibrous material, by a padding or coating method, a liquid composition containing the above components (1)-(3), followed by subsequent heat treatment.

Abstract: A vehicle body structure at mounting portions of tractive or fastening hooks of an automobile comprises U-shaped members welded to vehicle body members whose joint flanges surrounded by the U-shaped members are formed with apertures to reinforce the joint flange by bolts passing through the apertures, thereby preventing separations and cracks in the joint flanges during a transport for a long distance.