| 摘要 |
PURPOSE:To prevent operating oil from leaking outward from the forward end surface of a cylinder head by mounting a groove portion for an oil reservoir on the forward inner peripheral surface of the cylinder head. CONSTITUTION:A very small amount of oil, which passes through a gap between a wiper ring 9 and a piston rod 5 to come oozing outside of the siper ring 9, flows in the interior of a groove portion 12 through the inlet end portion 14 thereof and collects in an oil reservoir portion 13 little by little. The oil collected in the oil reservoir portion 13 is naturally evaporated from a space portion 16 formed between the inside peripheral edge of the front wall portion 15 of a cylinder head 7 and the outer peripheral surface of the piston rod 5, under the working condition of a high temperature during the daytime. Thus, oil is prevented from directly leaking outward from the cylinder head 7, unlike a conventional case. |
