US Patent 7594457 Method of machining work in numerically controlled lathe

In a method of machining a work in a numerically controlled lathe, it is possible to reduce machining cost by shortening idle time at the time of switching and to enhance the lifetime by lessening a load on a feeding mechanism of a tool rest. After completion of the machining of a work W with a tool T1 on one tool rest (13), the one tool rest (13) is moved to a standby position B and, at the same time, the other tool rest (15) is moved from a standby position D and the feed speed of the other tool rest (15) is controlled such that the one and the other tool rests (13, 15) simultaneously reach positions C and F preset between the work W and the standby positions B and D.