Oil circulation device and oil circulation system for agitating oil in oil bath

An oil circulation device for agitating oil in an oil bath, comprising:

• an oil bath having a first oil supply/discharge port and a second oil supply/discharge port;
• a circulation pump for circulating the oil;
• a pair of pipes for connecting the oil bath and the circulation pump;
• a first switching valve which is attached to the pipes so as to switch the oil supply/discharge direction for each of the first oil supply/discharge port and the second oil supply/discharge port;
• an oil collection tank which is located downstream of the circulation pump so as to collect oil;
• a new oil tank which is located upstream of the circulation pump so as to receive new oil;
• and
• a control unit for controlling at least the circulation pump and the first switching valve, wherein
• the control unit has:
• an agitation mode in which a command is executed for the first switching valve so that the oil supply/discharge direction is switched so as to supply oil to the first oil supply/discharge port located at a low position and discharge oil from the second oil supply/discharge port located at a high position, whereby oil in the oil bath is agitated via the circulation pump from a low position to a high position in the oil bath;
• and
• an oil exchange mode in which, after the agitation mode is executed so as to suspend impurities in the oil bath, a command is executed for the first switching valve so that the oil supply/discharge direction is switched so as to discharge oil from the first oil supply/discharge port located at a low position, whereby the oil is collected from the oil bath to the oil collection tank via the circulation pump, and a command is executed for the first switching valve so that the oil supply/discharge direction is switched so as to supply oil to the first oil supply/discharge port located at a low position, whereby the new oil is supplied from the new oil tank to the oil bath via the circulation pump.