Hollow engine valve and production method thereof
AssigneeFuji Oozx Inc.
InventorsTakaaki Kumagai, Koji Kushima
Life of this patent
Estimating the term…
Abstract
A hollow engine valve includes a shaft portion and an umbrella portion of which diameter is enlarged to form an umbrella shape to be provided on a base end of the shaft portion, a cooling material being enclosed in a hollow portion that is at least formed inside the shaft portion. The shaft portion comprises a first shaft portion in a tip end side, a second shaft portion that is provided in a base end side to have an outer diameter larger than that of the first shaft portion, and a stepped portion formed by a difference in the outer diameters between the first and second shaft portions. A wall thickness of the stepped portion is larger than that of the second shaft portion.
Claims9
A hollow engine valve comprising a shaft portion and an umbrella portion of which diameter is enlarged to form an umbrella shape to be provided on a base end of the shaft portion, a cooling material being enclosed in a hollow portion that is at least formed inside the shaft portion,
- wherein the shaft portion comprises a first shaft portion in a tip end side, a second shaft portion that is provided in a base end side to have an outer diameter larger than that of the first shaft portion, and a stepped portion formed by a difference in the outer diameters between the first and second shaft portions, and
- wherein each wall thickness of the first shaft portion and the stepped portion is larger than that of the second shaft portion.
A hollow engine valve comprising a shaft portion and an umbrella portion of which diameter is enlarged to form an umbrella shape to be provided on a base end of the shaft portion, a cooling material being enclosed in a hollow portion that is formed inside the shaft portion and the umbrella portion,
- wherein the shaft portion comprises a main shaft portion in a tip end side and a neck portion that is formed continuously from the umbrella portion to have an outer diameter larger than that of the main shaft portion,
- wherein a wall thickness of the neck portion is larger than that of the main shaft portion, and,
- wherein the hollow portion is formed to have an inner diameter which is fixed from the main shaft portion to the neck portion and is gradually increased from the neck portion to the umbrella portion toward a bottom portion.
Dependencies are inferred from the claim text.