Abstract: This invention is directed to a vibration damping soundproof sheet for use in vehicles, in which the surface of the soundproof layer is made flat irrespective of the or uneven configuration at the surface of a vehicle. The soundproof layer-forming material comprises a formed rubber blend in which a foaming agent and other rubber blending agents are blended with a rubber type polymer in which the soundproof layer-forming material contains from 15 to 85% by weight of 1,2-polybutadiene ingredient.

Abstract: A polyamide resin composition is described, which is characterized by blending a polyamide resin with a composition (A) comprising (i) either polyamide-rubber copolymer or polyolefin resin, and (ii) a tackiness providing resin wherein either said polyamide-rubber copolymer or the polyolefin resin is from 80 to 20% by weight based on the composition (A), and the tackiness providing resin is from 20 to 80% by weight based on the composition (A).

Abstract: An extrusion device comprises a die provided with feed passageways and grid-shaped extrusion slots, and a die mask covering the peripheral portion of the die on the extrudable material outlet side. The die mask is provided with a plurality of disconnected openings which are formed in the lower end of the inner surface thereof at predetermined intervals so as to be communicated with the extrusion slots of the peripheral portion of the die. By this extrusion device, the extrudable material is supplied from the openings into the outer periphery of the extruded body to form a honeycomb structure having a smooth outer peripheral surface and a thick outer wall.

Abstract: An extrusion device comprises a die provided with feed passageways and grid-shaped extrusion slots of which width is made larger in the outer peripheral portion compared with those of the central portion of the die. By the above extrusion device, a honeycomb structure having a thicker walled outer peripheral portion can be obtained without any distortion.

Abstract: An extrusion device comprises a die provided with disconnected feed passageways and interconnected grid-shaped extrusion slots and a die mask which covers the outer peripheral portion of the die on the extrudable material outlet side through a pooling zone. The width of the uncovered grid shaped extrusion slots along the die mask is made larger on the extrudable material outlet side compared with that on the extrudable material inlet side. The extrudable material is supplied from the covered extrusion slots into the uncovered extrusion slots through the pooling zone.

Abstract: An exhaust gas purifying apparatus having an exhaust pipe divided into at least two branches each connected to a different cylinder or cylinders. Each of the exhaust pipe branches is further connected to a secondary air supply tube to intermittently supply secondary air upstream of a three-way catalyst disposed in the branch thereby to vary periodically within a range the air-fuel ratio of exahust gases flowing into the three-way catalyst.

Abstract: A catalyst carrier high in strength and suitable for use in internal combustion engines is produced by transforming a boehmite into .gamma.-alumina at a high temperature, transforming the .gamma.-alumina into .alpha.-alumina at a high temperature and sintering the .alpha.-alumina, boehmite having been prepared by forming a large number of agglomerates of adequate size from powdered aluminum hydroxide (Al.sub.2 O.sub.3.3H.sub.2 O) and contacting the agglomerates with water vapor at a high temperature and a high pressure to transform the aluminum hydroxide into boehmite.

Abstract: An exhaust gas purifying system of the type utilizing a three-way catalyst containing an oxygen storage material includes an electronic control unit for controlling the amount of secondary air supplied to the exhaust system of an internal combustion engine. The electronic control unit receives a signal from an exhaust air-fuel ratio sensor indicative of an air-fuel ratio of the exhaust gases and provides a pulse signal to an electromagnetic valve disposed in the passage of the secondary air leading to the upstream of the three-way catalyst. The amount of secondary air supplied to the exhaust system is controlled such that the resultant exhaust gases having an exhaust air-fuel ratio greater than the stoichiometric ratio and those having an exhaust air-fuel ratio smaller than the stoichiometric ratio are alternately supplied to the three-way catalyst thereby to achieve the average exhaust air-fuel ratio to fall within the optimum purifying conditions of the three-way catalyst.

Abstract: A method of operating a three-way catalyst which contains an oxygen storage material and which is mounted on the exhaust system of an internal combustion engine is disclosed. In order to operate the three-way catalyst effectively, the air-fuel ratio of the mixture supplied to the engine is set to be richer than the stoichiometric ratio, and secondary air is intermittently supplied by an air pump into the exhaust system upstream of the three-way catalyst, thereby to alternately vary the air-fuel ratio of the exhaust gases supplied to the three-way catalyst to become rich and lean with respect to the stoichiometric ratio.

Abstract: A device for detecting the specific gravity and level of liquid in a container comprising a light source, a photoelectric transducer positioned in light receiving relationship with respect to the light source, a float which has a predetermined specific gravity and is displaced depending upon the change in specific gravity and level of the liquid, and means operatively coupled to the float so as to permit or interrupt the light transmission from the light source to the photoelectric transducer.