PURPOSE: To smoothly operate an upper base part even if the upper base part is thermally expanded by a warm working by providing an upper die to be combined with a lower die and by providing sliding surfaces between moving guides and fixed guides provided on at least three corners of the upper base part driving vertically in the radial directions from the center of the upper base part.
CONSTITUTION: The sliding surfaces 25 between the moving guides 22 provided at the four corner parts of the upper base part 18 and the fixed guides 21 opposed to said guides 22 are disposed along the radial directions from the center of the upper base part 18. And, between the top end surfaces 22a of the moving guides 22 and bottom planes 21a of the fixed guides 21, a clearance that is larger than the maximum value of the moving distance of the pitch of the moving guide 22 caused by the thermal expansion is provided. Therefore, without causing a biting on the sliding part due to the thermal expansion, the smooth operation is performed.
YONEYAMA SHIGEO
HORI YOSHIMICHI
SATO TAKAYUKI
| JPS5239081U | 1977-03-19 | |||
| JPS5417194A | 1979-02-08 |