Abstract
The present invention relates to a cooling device, which comprises a spindle holder and multiple flow guide pieces. The spindle holder comprises a spindle fixing trough and multiple cooling troughs that are not in communication with each other. The cooling troughs are circumferentially arranged around a circumference of the spindle fixing trough. Each of the flow guide piece comprises multiple separation boards. The flow guide pieces are each arranged, in a one-to-one manner, in the cooling troughs of the spindle holder, so that the flow guide pieces use the separation boards to delimit a flow guide channel in the cooling troughs. As such, the cooling device of the present invention allows a cooling liquid to flow into one or multiple ones of the cooling troughs in response to a temperature distribution of a spindle and the flow guide channel delimited by the flow guide pieces helps lengthens the distance by which the cooling liquid passes through the cooling troughs to extend a time period of cooling. Flowrate and entry temperature of the cooling liquid entering the cooling troughs can be timely adjusted to achieve an effect of allowing the spindle to fast reach heat balance.