Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Isolite Babcock Refractories Co., Ltd.

Masahiro Kubo

Tadashi Dohnomoto

Atsuo Tanaka

Kaneo Hamajima

Hidetoshi Hirai

Hiroshi Miyamoto

Koichi Kitaura

Yoshiaki Tatematsu

Yasushi Iwazaki

Tetsuya Suganuma

Ryozo Kayama

Tadashi Donomoto

Yoshiaki Kajikawa

Toshihiko Tanaka

Tetsuya Nukami

Kouichi Kitaura

Haruo Kito

Yasushi Iwasaki

Jun Ohkijima

An abnormality diagnosis system of an internal combustion engine which is provided with an exhaust purification catalystwhich can store oxygen is provided with a downstream side air-fuel ratio sensordownstream of the catalyst and a catalyst abnormality diagnosis system which uses an output air-fuel ratio of the downstream side air-fuel ratio sensor when performing active air-fuel ratio control as the basis for diagnosing an exhaust purification catalyst for abnormality. The catalyst abnormality diagnosis system uses the amount of oxygen which is stored in or released from the exhaust purification catalyst in an air-fuel ratio reversal time period in active air-fuel ratio control as the basis to calculate the maximum storable oxygen amount of the exhaust purification catalyst and uses this as the basis to diagnose the exhaust purification catalyst for abnormality.

Abnormality diagnosis system of internal combustion engine

An internal combustion engine comprises an exhaust purification catalyst which can store oxygen, controller for controlling the air-fuel ratio of exhaust gas to become a target air-fuel ratio, and a downstream side air-fuel ratio sensor. An abnormality diagnosis system performs an active air-fuel ratio control which alternately controls the target air-fuel ratio to rich and lean air-fuel ratios, and diagnoses abnormality of said exhaust purification catalyst based on the output air-fuel ratio of the air-fuel ratio sensor. The abnormality diagnosis system judges that the exhaust purification catalyst is abnormal when the output air-fuel ratio of the air-fuel ratio sensor reaches a rich judgment air-fuel ratio and a lean judgment air-fuel ratio during the active air-fuel ratio control, and judges that said air-fuel ratio control is abnormal when the output air-fuel ratio reaches only one of the rich and lean judgment air-fuel ratios.

The sulfur poisoning of a three-way catalyst is intended to be detected with a high degree of accuracy. It is determined whether the sulfur poisoning of the three-way catalyst is made to be recovered, or a determination is made that the degree of sulfur poisoning of the three-way catalyst is higher when the concentration of NOx detected by an NOx sensor is high than when it is low, based on the concentration of NOx downstream of the three-way catalyst after the air fuel ratio of the exhaust gas flowing into the three-way catalyst has been made to change from a rich air fuel ratio to a lean air fuel ratio and before the air fuel ratio of the exhaust gas flowing out of the three-way catalyst changes to a lean air fuel ratio.

Exhaust gas purification apparatus for an internal combustion engine

When a wastegate valve, which opens and closes an exhaust bypass passage bypassing an exhaust turbine, is open, exhaust gases of respective cylinders bypass the exhaust turbine and pass a sensing point of an air-fuel ratio sensor downstream of the exhaust turbine. Accordingly, the exhaust gases of the respective cylinders can be avoided from being mixed by the exhaust turbine, so an influence of an inter-cylinder variation in an air-fuel ratio due to an inter-cylinder imbalance abnormality becomes apt to appear in an output waveform of the air-fuel ratio sensor. Therefore, existence or nonexistence of the inter-cylinder imbalance abnormality is determined based on the output of the air-fuel ratio sensor when the wastegate valve is open. Eventually, the existence or nonexistence of the inter-cylinder imbalance abnormality can be determined accurately, thereby improving detection accuracy of the inter-cylinder imbalance abnormality.

Abnormality diagnostic device of internal combustion engine with turbocharger

A metal matrix composite material having uniformly dispersed intermetallic compounds and no micropores is manufactured by forming a porous preform including 60% to 80% by volume fine fragments essentially made of aluminum, 1% to 10% by volume fine fragments essentially made of nickel, copper or both, and 1% to 10% by volume fine fragments essentially made of titanium so that these fine fragments occupy in total 62% to 95% by volume of said preform, and at least a part of the preform is contacted with a melt of a matrix metal selected from aluminum, aluminum alloy, magnesium and magnesium alloy, so that the porous preform is infiltrated with the melt under no substantial application of pressure to the melt.

Method of manufacture of metal composite material including

A preform for being embedded in a matrix material for making a composite material is made essentially of many short fibers stuck together by a quantity of dried binder. This preform has a first portion in which the fiber volume proportion is relatively high, a second portion in which the fiber volume proportion is relatively low, and a third portion, joining between the first portion and the second portion, in which the fiber volume proportion changes substantially continuously from its portion adjoining to the first portion to its portion adjoining to the second portion. Thereby, the characteristics of the composite material, such as its strength, heat and wear resistance, and machinability and workability and characteristics with respect to wear on a mating member, alter smoothly from the first portion to the second portion without any severe discontinuity, thus ensuring that no points of weakness are caused. A method for making such a preform, and a composit material object manufactured using such a preform, which may be an engine piston, are also disclosed.

Short fiber preform, method of making it, and composite material

A composite material is made from reinforcing fiber material embedded in a matrix of metal. The matrix metal is a light metal such as aluminum alloy or magnesium alloy. The reinforcing fiber material is a mixture of potassium titanate whiskers and a short fiber material, which is one or a mixture of: silicon carbide whiskers, silicon nitride whiskers, alumina short fibers, crystalline alumina-silica short fibers, and amorphous alumina-silica short fibers. The overall volume proportion of the reinforcing fiber material in the composite material is between approximately 5% and approximately 50%, and more desirably may be between approximately 5% and approximately 40%, and even more desirably may be between approximately 10% and approximately 40%. And the relative volume proportion of the potassium titanate whiskers in the reinforcing fiber material is from about 10% to about 80%, and more desirably may be between approximately 10% and approximately 70%, and even more desirably may be between approximately 20% and approximately 60%.

Composite material with light matrix metal and with reinforcing fiber

A composite material is made from alumina-silica type short fibers embedded in a matrix of metal. The matrix metal is an alloy consisting essentially of from approximately 2% to approximately 6% of copper, from approximately 0.5% to approximately 3.5% of magnesium, and remainder substantially aluminum. The short fibers have a composition of from about 35% to about 80% of Al.sub.2 O.sub.3 and from about 65% to about 20% of SiO.sub.2 with less than about 10% of other included constituents, and may be either amorphous or crystalline, in the latter case optionally containing a proportion of the mullite crystalline form. The fiber volume proportion of the alumina-silica type short fibers is between approximately 5% and approximately 50%, and may more desirably be between approximately 5% and approximately 40%. If the alumina-silica short fibers are formed from amorphous alumina-silica material, the magnesium content of the aluminum alloy matrix metal may desirably be between approximately 0.5% and approximately 3%. And, in the desirable case that the fiber volume proportion of the alumina-silica type short fibers is between approximately 30% and approximately 40%, then the copper content of the aluminum alloy matrix metal is desired to be between approximately 2% and approximately 5.5%.

Composite material including alumina-silica short fiber reinforcing

In this method for making an alloy of a first metal and a second metal which has a stronger tendency to form an oxide than the first metal, a powdered solid is prepared comprising at least one of a compound of the first metal with oxygen and the second metal, the compound is mixed with the second metal, and an alloying process is carried out of alloying a melt with the powdered solid, in which the second metal is oxidized by the oxygen of the compound of the first metal with oxygen which is reduced. The compound of the first metal with oxygen may be an oxide, and may be a simple oxide or a compound oxide. As one variation, the powdered solid may contain the compound of the first metal with oxygen, in which case the melt will contain the second metal; or alternatively the powdered solid may contain the second metal, in which case the melt will contain the compound of the first metal with oxygen. Alternatively, the powdered solid may contain both the compound of the first metal with oxygen and the second metal, in which case the melt may contain a third metal.

Process for manufacturing alloy including fine oxide particles

In this method for manufacturing an aluminum alloy, a porous preform is manufactured from a mixture of a finely divided oxide of a metallic element which has a weaker tendency to form oxide than does aluminum, and an additional substance substantially more finely divided than that metallic oxide. Then an aluminum alloy containing a substantial quantity of silicon is permeated in the molten state through the porous preform. This causes the metallic oxide to be reduced by a thermite reaction, to leave the metal which it included as alloyed with the aluminum alloy. At this time, the silicon in the aluminum alloy does not tend to crystallize out upon the particles of the metallic oxide, which would interfere with such a reduction reaction by forming crystalline silicon shells around such metallic oxide particles and would lead to a poor final product, because instead the silicon tends to crystallize out upon the particles of the additional substance. This alloying method is effective even if the average particle diameter of the finely divided metallic oxide, on the assumption that it is in the form of globular particles, is less than about 10 microns. The melting point of the additional substance should desirably be substantially higher than the melting point of the aluminum alloy. The silicon content of the aluminum alloy may freely be greater than about 1.65% by weight. Desirably, the preform may further contain reinforcing fibrous material. And, particularly, the additional substance may be Al.sub.2 O.sub.3.

Method for manufacturing aluminum alloy by permeating molten aluminum

A composite material is made from silicon carbide and/or silicon nitride short fibers embedded in a matrix of metal. The metal is an alloy consisting essentially of between approximately 2% to approximately 6% of copper, between approximately 0.5% to approximately 3% of silicon, and remainder substantially aluminum. The short fibers may be all silicon carbide short fibers, or may be all silicon nitride short fibers, or may be a mixture of silicon carbide and silicon nitride short fibers. The fiber volume proportion of the silicon carbide and/or silicon nitride short fibers may desirably be between approximately 5% and approximately 50%, and may more desirably be between approximately 5% and approximately 40%.

Composite material including silicon carbide and/or silicon nitride

A piston of a light alloy matrix material having a cavity for containing heat insulating air immediately below its head or a cavity for passing cooling oil inside the grooved side wall is manufactured by preforming a precursory member having the shape of the cavity from an extractable material which remains in solid state at room temperature and is convertible into a fluid, gas or liquid when heated at a temperature below the melting point of the matrix metal. The precursory member is disposed in place in a pressure casting mold having a cavity corresponding to the shape of the piston, and covered with a porous member stable to the molten matrix metal. A head member of heat resisting metal material to constitute at least a portion of the piston head may be disposed on the mold cavity bottom. Molten matrix metal is then cast into the mold cavity and a pressure is applied thereto to form a piston-shaped casting having precursory member and porous member embedded therein. Finally the casting is heated at a sufficient temperature to gasify or liquefy the extractable material of the precursory member material into fluid, which is extracted from the casting, leaving a cavity at the location of the precursory member. Alternatively, the precursory member may be formed from a composite material of a gasifiable material and a stable material whereby the cavity is given as a porous insert of the stable material which is left after the extraction of the gasifiable material by heating.

Production of pistons having a cavity

An alloy is made of a first material and a second material which has a substantially lower melting point than the first material, by (a) forming from the first material a body which has multiple fine interstices; (b) pouring the second material in the molten state around the body formed from the first material; and (c) allowing the resultant mass to cool. Thus, in the parts of the resultant mass in which the body formed from the first material was originally present, an alloy mass comprising the first metal and the second material alloyed together is made. Optionally, the body made from the first material may be preheated, desirably to a temperature higher than the melting point of the second material; and optionally the molten second material may be pressurized so as to enter into the interstices of the body. The first material may desirably be, for example, tungsten, cobalt, chromium, titanium, iron, nickel, silicon, manganese, copper, niobium, tantalum, vanadium, gold, silver, aluminum, molybdenum, zirconium, or zinc; and the second material may desirably be, for example, aluminum, magnesium, copper, lead, tin, or zinc.

Method for alloying substances

This composite material includes reinforcing hybrid fiber mixture material in a matrix of metal which is aluminum, magnesium, copper, zinc, lead, tin, or an alloy having these as principal components. The hybrid fiber mixture is a mixture of crystalline alumina-silica fiber material and mineral fiber material. The crystalline alumina-silica fiber material has as principal components 35% to 80% by weight of Al.sub.2 O.sub.3 and 65% to 20% by weight of SiO.sub.2, with a content of other substances of less than or equal to 10% by weight, and with the percentage of mullite being greater than or equal to 15% by weight, and with the percentage of non fibrous particles with diameters greater than 150 microns being less than or equal to 5% by weight. And the mineral fiber material has as principal components SiO.sub.2, CaO, and Al.sub.2 O.sub.3, the content of MgO being less than or equal to 10% by weight, the content of Fe.sub.2 O.sub.3 being less than or equal to 5% by weight, and the content of other inorganic substances being less than or equal to 10% by weight, with the percentage of non fibrous particles being less than or equal to 20% by weight, and with the percentage of non fibrous particles with diameters greater than 150 microns being less than or equal to 7% by weight. The volume proportion of the reinforcing hybrid fiber material is at least 1%. The qualities of this composite material with regard to wear, wear on a mating member, and bending strength are good.

Composite material made from matrix metal reinforced with mixed

A composite material, including reinforcing fiber material with principal components SiO.sub.2 and/or CaO and/or Al.sub.2 O.sub.3, and with a Mg content by weight of between about 0% and about 10%, an Fe.sub.2 O.sub.3 content by weight of between about 0% and about 5%, and a content by weight of other inorganic substances of between about 0% and about 10%, and consisting essentially of mineral fibers and non fibrous particles to a total percentage of not more than about 20% by weight, the weight percentage of the part of the non fibrous particles which have a diameter of greater than or equal to about 150 microns being between about 0% and about 7%. Also, the composite material includes a matrix metal selected from the group consisting of aluminum, magnesium, copper, zinc, lead, tin, and alloys having these as principal components, the volume proportion of the mineral fibers being in the range of from about 4% to about 25%. This composite material is economical to manufacture and has very good wear characteristics, machinability, and bending strength.

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Toyota, Japan

Masahiro Kubo