Cutting fluid circulation device

A cutting fluid circulation device comprising:

• a tank reservoir that stores cutting fluid discharged from a machine tool;
• a drum filter disposed in the tank reservoir, the drum filter as a primary filter that filters cutting fluid;
• a secondary filter disposed outside the tank reservoir;
• a pump that pumps up cutting fluid in the tank reservoir,
• an annular flow channel formed in the tank reservoir, the annular flow channel being configured to circulate the cutting fluid filtered by the drum filter;
• a first pipe configured to supply a part of the cutting fluid pumped up by the pump to the drum filter;
• and
• a second pipe configured to supply a remaining part of the cutting fluid pumped up by the pump to the secondary filter,
• wherein the first pipe is configured such that cutting fluid supplied to the drum filter is used for cleaning the drum filter and is then returned to the annular flow channel, and
• the second pipe is configured such that cutting fluid supplied to the secondary filter is filtered by the secondary filter and is then returned to the annular flow channel.