To provide a rotary table device that can prevent the occurrence of malfunction before it happens. A rotary table device equipped with both or one of a clamping mechanism and purge mechanism which operate by way of working fluid, the rotary table device including: a detection unit that detects a pressure or flow rate of the working fluid; a transition information storage unit that acquires and stores transition information related to transition of a pressure value or flow rate value of the working fluid detected by the detection unit; a judgment value storage unit that stores in advance a plurality of sets of judgment value information related to judgment values for judging a pressure value or flow rate value of the working fluid; and a notification unit that notifies of notification information according to the pressure value or flow rate value of the working fluid, based on the transition information stored in the transition information storage unit and the plurality of sets of judgment value information stored in the judgment value storage unit.

A gas-curtain protection device for an aerospace precision machining spindle includes a spindle body, a shaft, a first labyrinth ring, a gas guide ring and a bulkhead ring. The first labyrinth ring and the gas guide ring are mounted around the front end of the spindle body, and the bulkhead ring is mounted around the shaft. The first labyrinth ring has a gas pipe, and the gas guide ring has a gas tank communicated with the gas pipe. The bulkhead ring has a gas guide structure communicated with the gas tank. In use, gas is delivered from the spindle body to the gas tank through the gas pipe, and then guided to the exterior of the spindle body by the gas guide structure so as to form a gas curtain that effectively prevents cutting fluid and chips from entering the interior of the spindle body.

A rotation table mounted on a machining table of a machine tool includes a clamping mechanism which is driven by air so as to clamp a rotation shaft, and an air purging pressure is applied into a casing so as to prevent a cutting fluid or foreign matter from intruding into the casing of the rotation table. Then, air discharged from the clamping mechanism does not pass through the casing, to which the air purging pressure is applied, and is discharged to the outside of the rotation table through a flow passage.