| 摘要 |
PURPOSE:To prevent grease from sticking to a spherical valve and to avoid an occurrence of an unsatisfactory performance by deppressing the spherical valve of an overflow prevention valve to return to the initial position at a place apart from the grease coated section on the sliding faces of a plug and a cock main body. CONSTITUTION:When an overflow condition occurs with a plug 1 at a fully opened position, a spherical valve 3 is raised in a cylindrical body 5 and is inserted into a valve seat port 4 to cut off a gas passage 7. Under this closed valve condition, a part of the spherical valve 3 protrudes into a side hole 12 of the plug 1 through the valve seat port 4, and when the plug 1 is rotated to a close position, the spherical valve 3 is deppressed into the cylindrical body 5 by means of the periphery of the side hole 12, returning to the initial condition. During this reset operation, the portion which the spherical valve 3 gets into contact with is the side hole 12 apart from the grease section coated on the sliding faces of the plug 1 and a cock main body 6, thereby grease will not stick to the spherical valve 3 and an occurrence of an unsatisfactory performance can be prevented. |
