| 摘要 |
PROBLEM TO BE SOLVED: To prevent water from leaking from an O ring owing to pressure variation of cooling water, etc., by providing a rod holding structure which can press an O ring at the base end of a rod holder against the outer peripheral surface of an end part of a laser rod tightly with large contact area. SOLUTION: The rod holding structure holds the axial end part of the laser rod 2 in a cavity 1. On the base end side of the rod holder 21 into which the end part of the laser rod 2 is inserted, a diameter-reduced part 28 is formed which tapers an opening 27 on the base end side to a diameter nearly equal to the external diameter of the laser rod 2. The O ring 24 is fitted and mounted in a triangularly sectioned groove formed between the diameter-reduced part 28 and an inner ring 29 and a lock ring 31 engaged threadably with the inner peripheral surface of the tip side of the rod holder 21 is clamped to hold the O ring 24 between the diameter-reduced part 28 and inner ring 29. |
