| 摘要 |
PURPOSE:To perform reliable and smooth operation, by a method wherein an air bleeding passage, exhausting the air contained in working fluid in an oil chamber in a tappet body, is formed at a juncture between an approximately cylindrical guide part, acting as a tappet body, and a tappet head. CONSTITUTION:A direct-acting type tappet valve mechanism is formed such that a tappet head part 9 of a tappet body 2 is forcibly pressed through rotation of a cam 1, the whole tappet body 2 is lowered as it is guided by means of a guide hole 6 formed in a cylinder head 5, and a valve 4 is opened. When a plunger 12, vertically moving in linkage with opening and closing of the valve 4, is restored upward through the elastic force of a spring 18, a check valve 28 is forcibly opened by a differential pressure to suck working fluid from an oil chamber 15 to an oil chamber 16, and this causes a valve clearance to be brought to zero. Further, an air bleeding passage 35 is formed at a juncture 34 between the tappet head 9 and a guide part 7, and this enables exhausting of the air, contained in working fluid in an annular oil chamber 26, to the atmosphere. |
