Honda Giken Kogyo Kabushiki Kaisha

Other

Nippon Steel Corporation

Kabushiki Kaisha Riken

Honda Giken Kogyo Kabushiki

Noriyuki Yamada

Chikara Tanaka

Junichi Iwamoto

Tsutomu Saka

Hiromu Nakamura

Akira Fujiwara

Toshiki Kobayashi

Toshihiro Oikawa

Takeya Harada

Tsuneo Tanai

Atsushi Takahashi

Hiroshi Hagiwara

Masayuki Hashimura

Takeshi Sugawara

Takanori Shiina

Yoshiharu Abe

Seiichi Koike

Yukihiro Matsumoto

Tomonori Niizato

Hiroaki Hayashi

Nobuki Matsuo

Takanari Miyaki

Kazushige Yakubo

Katsuaki Shiiki

Makoto Asami

Takaaki Harasaki

Tetsuya Kajiura

Masayasu Tajima

Kaoru Kamibayashi

Fujio Itabashi

Toshiaki Ohnuma

Tomotaka Takahashi

Shouich Suzuki

Yoshiyasu Fukui

Yoshinori Akagawa

Setsuo Kikuchi

Kenji Yoshihara

The present invention provides a steel wire, for springs excellent in coiling property while having a high strength, as a heat treated steel wire for high strength springs, characterized by: comprising, in mass, C: 0.75 to 0.85%, Si: 1.5 to 2.5%, Mn: 0.5 to 1.0%, Cr: 0.3 to 1.0%, P: not more than 0.015%, S: not more than 0.015%, N: 0.001 to 0.007%, W: 0.05 to 0.3%, and the balance consisting of Fe and unavoidable impurities; having a tensile strength of not less than 2,000 MPa; spheroidal carbides, composed of mainly cementite, observed in a microscopic visual field satisfying the area percentage of the spheroidal carbides not less than 0.2 &#x3bc;m in circle equivalent diameter being not more than 7%, the density of the spheroidal carbides 0.2 to 3 &#x3bc;m in circle equivalent diameter being not more than 1 piece/&#x3bc;m, and the density of the spheroidal carbides over 3 &#x3bc;m in circle equivalent diameter being not more than 0.001 piece/&#x3bc;m; the prior austenite grain size number being #10 or larger; the content of the retained austenite being not more than 12 mass %; the maximum diameter of carbides being not more than 15 &#x3bc;m; and the maximum diameter of oxides being not more than 15 &#x3bc;m.

Heat-treated steel wire for high strength spring

An iron-based alloy comprises 1.5 to 2.5 wt % of C, 0.25 to 4.75 wt % of Ni, and W and V in quantities surrounded by the line L as shown in FIG.of the attached drawings with a balance of Fe and inevitable impurities. The iron-based alloy is obtained by a first heat treatment for applying a solid solution treatment by rapidly cooling the iron-based alloy from a temperature of an austenite forming temperature or more to consequently obtain a mixed matrix comprising a base matrix of martensite and remaining austenite phases and a non-molten carbide, and a second heat treatment for cooling the iron-based alloy after precipitating an MC type carbide within an eutectoid transformation temperature range to consequently precipitate a low carbon content austenite phase.

Iron-based alloy and method for production thereof

A valve train for an internal combustion engine includes a rocker shaft ( ) provided with an oil passage, first and second rocker arms ( ) having support parts ( ) provided with bores ( ) to receive the rocker shaft ( ) therein so as to be supported on the rocker shaft ( ) for rocking motion, and a rocker arm interlocking mechanism ( ) for selectively engaging or disengaging the first and the second rocker arms ( ). The first rocker arm ( ) is provided with a pressure chamber ( ) holding a piston ( ) therein, a straight connecting passage connected to the pressure chamber ( ) and an oil passage ( )formed in the rocker shaft ( ). An open end surface ( ) of the bore ( ) of a first support wall ( ) of the rocker arm ( ) is on an axially outer side of the pressure chamber ( ). The straight connecting passage ( ) is inclined to the axis of the bore ( ) so that an imaginary passage ( ) on an extension of the connecting passage ( ) extended toward the open end surface ( ) intersects the open end surface ( ). The outermost side surface ( ) of the first support wall ( ) has an inclined section inclined to the axis of the bore ( ) along the connecting passage ( ).

Valve train for internal combustion engine

The present invention provides a valve operating system for internal combustion engines, having a roller rolling contacting a valve operating cam, the system being provided with an oil supply passage capable of reducing a pressure loss to a low level even when a flow rate of lubricating oil entering the oil supply passage increases in accordance with a heightened engine speed, improving the lubricating ability with respect to the roller, and attaining a long lifetime of a rocker arm. This valve operating system includes a rocker arm support member provided with an oil passage in an inner portion thereof, a cam shaft provided on a valve operating cam, and a rocker arm which is provided with a roller rolling contacting the valve operating cam, and which is provided in an inner portion thereof with an oil supply passage for supplying a lubricating oil from the rocker arm support member to the roller, the sectional area of the flow passage of the oil supply passage increasing gradually from an opening thereof on the side of the roller toward an opening thereof on the side of the rocker arm support member.

Valve operating system for internal combustion engines

A valve operating system in an internal combustion engine includes an associative-operation switchover means capable of switching over the associative operation of a pair of rocker arms disposed adjacent each other and the releasing of the associative-operation. The associative-operation switchover means is provided between a plurality of rocker arms including the rocker arms disposed adjacent each other. In such valve operating system, through-bores are coaxially provided in support walls of the rocker arm, and opposite ends of a roller shaft are fitted and fixed in the through-bores. A spring-receiving member is mounted to the roller shaft for receiving a return spring. Thus, when the roller shaft with the return spring of the associative-operation switchover means accommodated therein is mounted to the rocker arm, it is possible to facilitate the processing and to reduce the size and weight of the rocker arm.

Valve operating system in internal combustion engine

In a valve operating system in an internal combustion engine, a swinging support section provided at a base end of a rocker arm is swingably carried on a rocker shaft mounted in a cylinder head. A plurality of valve abutments are provided at a tip end of the rocker arm and capable of being individually put into abutment against upper ends of a plurality of engine valves, and a cam abutment is provided on the rocker arm in an intermediate portion between the swinging support section and each of the valve abutments to come into contact with a valve operating cam. The swinging support section comprises a thinner cylindrical portion surrounding the rocker shaft, and thicker cylindrical portions which are formed at a thickness larger than that of the thinner cylindrical portion into a cylindrical shape to surround the rocker shaft and which are integrally and continuously provided at axially opposite ends of the thinner cylindrical portion, respectively. Thus, it is possible to enhance the durability of the rocker arm, while avoiding an increase in weight of the rocker arm.

A method for heat treating a mold cast product by releasing the product from a mold and hardening the product. Since the mold release is performed when a surface layer of the product held in contact with the mold has a hardening allowing temperature and after it becomes a shell-shaped solidified layer, the product immediately after release from the mold has a heat suitable for hardening. Using this heat, the product is thereafter hardened by means of a cooling agent. As a result, a heating process required for hardening can be omitted, thereby achieving energy conservation.

Method for heat treating mold cast product

In a valve operating system in an internal combustion engine, a swinging support section provided at a base end of a rocker arm is swingably carried on a rocker shaft, and tappet screws are threadedly fitted in a plurality of boss portions formed at a tip end of the rocker arm and arranged in a direction parallel to an axis of the rocker shaft, so that they can be individually put into abutment against upper ends of a plurality of engine valves. Cam abutments are provided on the rocker arm in an intermediate portion between the swinging support section and the boss portions to come into contact with a valve operating cam. The boss portions are interconnected by a connection wall having a plurality of wall portions which intersect each other in a plane perpendicular to the axis of the rocker shaft. Thus, the rigidity of the tip end of the rocker arm is enhanced sufficiently.

In a valve operating system in an internal combustion engine, a rocker arm has a plurality of valve abutments provided thereon and capable of being individually put into abutment against upper ends of a plurality of engine valves cam abutments, and also has cam abutments provided thereon to come into contact with a valve operating cam. Wall-removed portions are formed in the rocker arm at locations corresponding to the cam abutments and open at opposite sides of the rocker arm. Thus, it is possible to provide a reduction in weight of the rocker arm.

A valve operating system in an internal combustion engine includes a switchover pin which is movable between an associatively operating position where adjacent ones of rocker arms are operated in association with each other, and an associative-operation releasing position where the associative-operation is released, the switchover pin receiving at axially opposite ends thereof a hydraulic pressure force acting toward the associatively operating position and a spring force acting toward the associative-operation releasing position, a cylindrical roller shaft which is fixed to one of the adjacent rocker arms, and into which the switchover pin is slidably fitted in response to the movement thereof toward the associatively operating position, and a roller rotatably carried on the roller shaft to come into rolling contact with a cam provided on a camshaft. In this valve operating system, at least one of axially opposite end surfaces of the roller shaft formed of a material harder than that of the one rocker arm, which receives the switchover pin, protrudes from a side surface of the one rocker arm. Thus, a wear powder can be prevented from entering into the roller shaft, thereby ensuring the smooth switching-over operation of the switchover pin.

One of adjacent rocker arms in a valve operating system of an engine is provided with first and second support walls. A roller is disposed between the first and second support walls to come into rolling contact with cams. A cylindrical roller shaft, supporting the roller, is provided between the first and second support walls, so that a switchover pin of an associative-operation switchover means can be slidably fitted into the roller shaft in response to the movement thereof. The roller shaft is press-fitted into at least a second one of the first and second support walls, and a press-fit margin for the roller shaft press-fitted into the second support wall on the side of the other rocker arm is set smaller than a press-fit margin for the roller shaft press-fitted into the second support wall on the side of the roller.

A combustion system for reducing an amount of air polluting substances in a combustion exhaust gas produced in a combustion furnace comprises a combustion furnace configured to produce a combustion exhaust gas upon combustion of a combustible material, wherein the combustion exhaust gas contains an amount of air polluting substances; an analyzer suitable for analyzing the combustion exhaust gas and producing an analytical signal; a conduit suitable for conducting the combustion exhaust gas from the outlet opening to the analyzer, wherein the conduit is located adjacent the outlet opening of the combustion furnace; a controller suitable for processing the analytical signal produced by the analyzer and outputting a first control signal and a second control signal, based on the analytical signal; a neutralizer supplier suitable for supplying the combustion furnace with an amount of neutralizers to reduce the amount of air polluting substances in the combustion exhaust gas, wherein the amount of neutralizers supplied to the combustion furnace is based on the first control signal outputted by the controller; and an operating condition readjuster suitable for readjusting at least one operating condition of the combustion furnace selected from the group consisting of (1) a temperature of the combustion furnace, (2) a time for combusting the combustible material, and (3) an air flow in the combustible furnace, to reduce the amount of air polluting substances in the combustion exhaust gas, wherein the at least one operating condition is readjusted based on the second control signal outputted by the controller.

Combustion system for sooty smoke generating facilities

In carrying out a cast-in process, a cast-in insert member is placed into a cast forming cavity in a casting mold, and a casting is conducted. The cast-in insert member has a barrier layer on its non-deposited surface for inhibiting the deposition of a molten metal. During casting, a portion of a molten metal is introduced to a heating chamber on the side of the barrier layer to come into contact with the barrier layer. Thus, the cast-in insert member can be heated not only from the side of its deposited surface, but also from the side of its non-deposited surface, thereby providing an enhanced strength of deposition of the cast-in insert member.

Cast-in process

In producing a rocker arm, following steps are used: fabricating a rocker arm blank which includes: a rocker arm body having an aperture therein adapted to be converted to a hole for the insertion of a shaft, and which blank is made of a nitrided steel comprising specified amounts of C, Mn, Cr, Al, Si, P, S, Cu, Ni, one of Pb and Bi, and optionally Mo, and, as the balance substantially, Fe; and a slipper surface forming piece; subjecting the rocker arm blank to a refining treatment to adjust its hardness; subjecting the apertures to reaming to form the shaft insertion holes; and subjecting the rocker arm blank with the shaft insertion holes formed therein to a nitriding treatment. Thus, it is possible to mass-produce rocker arms for an internal combustion engine, each of which has excellent mechanical properties.

Process for producing rocker arm for internal combustion engine

A cast iron slide member is formed from cast iron comprising 3.0% to 3.6% by weight of carbon (C), 1.6% to 2.4% by weight of silicon (Si), 0.2% to 1.5% by weight of manganese (Mn), 0.5% to 1.5% by weight of chromium (Cr), 1.5% to 3.0% by weight of nickel (Ni), 0.5% to 1.0% by weight of molybdenum (Mo), 0.0003% to 0.1% by weight of at least one chilling promoting element E.sub.L selected from the group consisting of bismuth (Bi), tellurium (Te) and cerium (Ce), and the balance of iron (Fe) and unavoidable impurities. The slide member has a chilled slide portion. Thus, it is possible to improve the scuffing and pitting resistances of the slide portion.

Growing community of inventors

Wako, Japan

Noriyuki Yamada