Abstract: There is provided an oil/air lubrication system capable of surely detecting lubrication oil in oil/air adapted to be fed into a rotary portion of a machine tool. A detection means which is provided to a pipe line in the vicinity of a mixing valve, just downstream of the mixing valve, is adapted to detect a flow of lubrication oil with the use of electromagnetic waves, and accordingly, a flow of air/oil can be accurately detected, irrespective of vibration of the machine tool, influence by the gravity, variation in the flow and a length of the pipe line from the mixing valve to the machine tool, and irrespective of a viscosity of the lubrication oil, and as well, irrespective of the installation of the detecting portion of the detecting means in a vertical direction or a horizontal direction.

Abstract: There is provided an oil/air lubrication system capable of surely detecting lubrication oil in oil/air adapted to be fed into a rotary portion of a machine tool. A detection means which is provided to a pipe line in the vicinity of a mixing valve, just downstream of the mixing valve, is adapted to detect a flow of lubrication oil with the use of electromagnetic waves, and accordingly, a flow of air/oil can be accurately detected, irrespective of vibration of the machine tool, influence by the gravity, variation in the flow and a length of the pipe line from the mixing valve to the machine tool, and irrespective of a viscosity of the lubrication oil, and as well, irrespective of the installation of the detecting portion of the detecting means in a vertical direction or a horizontal direction.