| 摘要 |
PROBLEM TO BE SOLVED: To eliminate accidental leakage of a liquid even if the thread of a lid may be tightened loosely by protrusively arranging a guide cylinder inside so that the outer circumference part thereof exceeding a specified vertical width is made to slide freely on an internal wall part of a liquid supply port of a liquid vessel exceeding a specified vertical width to ensure that the thread part of the lid is screwed fit on the liquid vessel. SOLUTION: The outer diameter of a guide cylinder 14 arranged protrusively inside a lid 20 is set slightly less than the diameter of an internal wall part 103 of a liquid supply port 22 of a liquid vessel 21. As the vertical widths of the outer circumference part of the guide cylinder 14 and the internal wall part 103 are set exceeding specified values, meaning that there is no point contact, when the lid 20 is put on the liquid vessel 21, the guide cylinder 14 of the lid 20 guides the lid so as to be inserted straight into the liquid supply port 22. Thus, even when the female thread 201 of the lid 20 is screwed incompletely on the male thread 101 of the liquid supply port 22, that is, the lid 20 fails to be tightened to the end, an 0 ring 16 fitted into a groove 142 of the outer circumference part of the guide cylinder 14 is pressed being kept airtight on to the internal wall part 103 of the liquid supply port 22 thereby preventing leakage of a hazardous liquid inside. |
