Toyota Jidosha Kabushiki Kaisha

Toyota Jidosha Kogyo Kabushiki Kaisha

Atsushi Ota

Hidehiko Kadono

Hiroaki Mori

Minoru Uozumi

Yasuyuki Arakawa

Seizi Uda

Shinichi Yoshida

Hirokazu Onishi

Mitsuhiro Karaki

Tamotsu Hasegawa

Shingo Nakamura

Masaaki Tokui

Toshika Masaoka

Shigeki Tamura

Seiji Uda

Masatada Nakamichi

Satoshi Yamada

A process for casting a pipe such as a delivery pipe with transversal holes, the pipe having an elongate longitudinal hole and at least one pair of transversal holes communicating with the longitudinal hole in a substantially normal direction thereto. The process comprises the steps of positioning a rod-like center pin for forming the longitudinal hole in a predetermined positional relation to a cavity formation surface of a casting die, positioning a pair of mandrel pins for forming the pair of transversal holes such that end faces thereof are in contact with side surfaces of the center pin, and charging molten metal into a die cavity after the center pin and the pair of mandrel pins have been positioned. The molten metal is charged under the condition that the center pin is prevented from deforming by the pair of mandrel pins.

Process for casting pipe with transversal hole, and casting die for the

A method of casting a pipe having an axially elongate hole of which a front end is closed, comprises the steps of positioning a rod-like center pin for forming the blind hole in a predetermined positional relation to cavity defining surfaces of a die cavity, supporting the positioned center pin sidewise with a support pin to prevent positional deviation of the center pin, charging molten metal into the die cavity, retreating the support pin apart from the center pin, and replenishing a space formed by the retreat of the support pin with molten metal.

Method of and apparatus for casting pipe

A casting mold includes a cavity formed therein, and an auxiliary mold projecting into the cavity. The auxiliary mold forms a concave portion in a cast product, and it exhibits a thermal expansion coefficient being more than a thermal expansion coefficient exhibited by a molten metal to be charged into the cavity. Hence, the auxiliary mold greatly expands thermally during casting, and it keeps the expanded state during the solidification of the molten metal. Accordingly, the casting mold can prevent the casting defects resulting from the shrinkage cavities from arising in the resulting cast products. All in all, the casting mold can obviate to give the auxiliary mold a tapered configuration, and it can reduce the after-casting machining allowance to be provided in the resulting concave portion.

Casting mold

Apparatus for and method of vacuum casting

In a vacuum casting method, a mold cavity is reduced in pressure to a vacuum, and when a gate is opened, a molten metal which has been raised to a molten metal retaining dome is charged into the cavity at a high speed. When a portion of a molten metal held in a molten metal holding furnace is raised to the molten metal retaining dome, an upper surface of the molten metal is moved downwardly and upwardly through at least one cycle in the molten metal retaining dome, or a swirl flow is generated in the molten metal in a stalk. Such a unique motion as the downward and upward motion or the swirl flow effectively operates to detach solid metal pieces from an inside surface of the molten metal retaining dome or the stalk to push them to an upper portion of the molten metal. As a result, the detached metal pieces are prevented from being charged into the mold cavity to thereby cause defects in a cast product.

Vacuum casting method

Vacuum casting apparatus

A method of casting including the steps of closing gates with a counter tip after lower and upper molds heated to a predetermined temperature have been clamped, pouring melt into a sleeve in which a plunger tip is lifted a predetermined distance, lowering the plunger tip while displacing the counter tip to a predetermined position to open the gates, which are formed such that the ratio of the volume of products to the cross-sectional area of the gates is 20-40 (i.e. the volume of products/(CM.sup.3) cross-sectional area of gates (CM.sup.2)=20-40), to allow the melt to flow into cavities via the gates by the force of gravity alone with the plunger tip reaching the upper surface of the melt the moment a percentage of the melt placed in the cavities has reached a value between 30 and 70%, and pressure-filling the cavities with the melt by the plunger tip with the melt passing through the gates at 0.4-0.8 m/sec.

Vertical type pressure casting method

Growing community of inventors

Toyota, Japan

Atsushi Ota