Vacuum Filter

After preset level of vacuum is reached, it is broken temporarily by opening actuated by-pass valve. Part of dirt-laden filter paper is pulled out to be replaced by fresh filter paper. Dirt is dumped in a bin while dirty filter paper is wound on a shaft. A perforated top vacuum chamber is placed at the bottom of dirty coolant tank. Machine outlet lets dirty coolant in this tank. A pump sucks coolant through filter paper laid on top of vacuum chamber, leaving dirt on filter paper. Pump suction generates vacuum increasing dirt layer thickness & hence finer filtration.