Patent ID: 9599224
Date: 2017-03-21
CPC Classifications: B63C,F16J

Claim:
1. A shell of a pressure-resistant container, comprising: a shell portion which has a curved shape and is made only of ceramics and has a convexly-curved surface; and a thick-walled portion which has a curved shape and is made only of ceramics, continues into the shell portion, is larger in thickness than the shell portion, and has a through hole penetrating through the thick-walled portion in a thickness direction thereof, the thick-walled portion being defined in part by an imaginary spherical surface, wherein the shell portion includes a shell-portion inner surface defined by part of an imaginary spherical surface having a first radius of predetermined length, and a shell-portion outer surface defined by part of an imaginary spherical surface having a second radius which is longer than the first radius, and the thick-walled portion includes a thick-walled-portion inner surface defined by part of an imaginary spherical surface having a third radius which is shorter than the first radius, and a thick-walled-portion outer surface defined by part of an imaginary spherical surface having a fourth radius which is longer than the second radius, and an angle, which is formed between straight lines connecting a center point of a half sphere with points of the thick-walled portion where a thickness of the thick-walled portion begins to decrease toward the shell portion, that is in a range of 20° to 30°.