Movable main shaft of lathe tailstock

The utility model discloses a movable main shaft of a lathe tailstock, and relates to the technical field of numerical control lathe machining. The shaft head comprises a shaft head inner check ring, a bearing spacer sleeve is arranged on one side of the shaft head inner check ring, and a first O-shaped ring and a second O-shaped ring are arranged on one side of the shaft head inner check ring. A shaft head outer check ring matched with the first O-shaped ring and the second O-shaped ring is arranged on the peripheral side of the bearing spacer sleeve. Through the arrangement of the shaft head outer check ring, the main shaft can be tested on a machine, the load is 150 Kg, the rotating speed is 3000 revolutions, the temperature of the main shaft is constant at 25 DEG C when the main shaft continuously operates for 8 hours, and the waterproof and dustproof effects are good. 本实用新型公开了一种车床尾架活动主轴，涉及数控车床加工技术领域。本实用新型包括轴头内挡圈，轴头内挡圈一侧装设有轴承挡套，轴头内挡圈一侧装设有第一O型圈、第二O型圈；轴承挡套周侧装设有与第一O型圈和第二O型圈相配合的轴头外挡圈。本实用新型通过设置的轴头外挡圈，能使主轴经上机测试