A calculation coefficient setting unit sets feedback control calculation coefficients to a value between a first feedback control calculation coefficient value for a machining feed and a second feedback control calculation coefficient value for a speed-up operation that is smaller than the first feedback control calculation coefficient value. A calculation coefficient changing unit continuously changes the feedback control calculation coefficient from the second feedback control calculation coefficient value to the first feedback control calculation coefficient value in a first period between a first time which is an arbitrary time during the speed-up operation and a second time after the first time , or a second period between a third time after the first time and before the second time, and the second time when it is predicted at the first time that the operation command at the second time switches from the quick shift operation command to the machining feed command.
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