US Patent 10414008 Method for supplying cutting oil

A method for supplying cutting oil in a machine tool for cutting work pieces, including the steps of retaining cutting oil in a minimum reference quantity or an initial reference quantity in the cutting-oil tank, measuring a supply quantity per unit time q of the cutting oil flowing out from the cutting-oil tank and supplied to a cutting area of work pieces, either supplying the cutting oil to the cutting-oil tank by a quantity per unit time q′ larger than q and the supply is stopped in the case where the cutting-oil tank is filled, and the supplying and stopping are repeated as necessary, or supplying the cutting oil to the cutting-oil tank by a quantity per unit time equal to the supply quantity per unit time q.