Binoculars switching filter is applied to the nominal pressure 0.6Mpa thin oil lubrication system, respectively, by two groups filter cartridges and a three six-way valve components, A filter in normal use to reach the peak differential pressure, the filter should be replaced. Through the A / B valve switch to the B filter, this time A filter can be opened, remove the used filter element to replace the new one, installed, waiting for B to reach the service life of the filter and then switch back to A Filter, one tube work, one spare tube, can be achieved without stopping to switch the filter cartridge, reaching circulation lubrication system of uninterrupted work purposes.