FIELD: machine tools. SUBSTANCE: invention can be used to control the speed of the main drive of a lathe, which is equipped with a cutter with a coolant supply device and with a built-in system for automatic throttle control of the coolant supply, having a throttle limit sensor with a status indicator of this sensor. The system comprises a programmable controller, the output of which is configured to be connected to the control input of the drive through a code-voltage converter and a programmable voltage limiter. At the same time, it is equipped with a drive start and stop station with free run-out, a drive stop station with forced braking, as well as two-input AND, OR, and DISABLE logic elements. The start and stop station includes a control button connected to the T-flip-flop input, one of the outputs of which is connected to the corresponding indicator of the system operation mode, and the other to the station output. EFFECT: expanding range of cutting temperature reduction, which is provided only by controlling the coolant supply, which leads to an increase in tool life and an increase in the quality of part processing. 1 cl, 1 dwg.