| 摘要 |
A closed crankcase emission control system (10) for an internal combustion engine (12) includes a replaceable filter element (73) having a ring of filt er media (94) ; a first end cap (96) at one end of the media ring (94); a sump container defined by a second end cap (98) at the other end of the media rin g and a cup-shaped valve pan (128) fixed to the second end cap; and a check valve (140) in the valve pan to block blow-by gas flow directly into the filter element during engine operation, and to allow collected oil to flow o ut of the sump container during engine idle or shut-down. A shut off valve (160 , 200) is provided to prevent oil from passing through the emission control system to the engine. The shut off valve comprises a cylindrical float membe r (162) with a supporting body (164) and a seal (166), where the body includes a guide member (169). The float member could also be a ball valve (214, 272). The float member (162) floats with the level of oil in the housing, and can fluidly seal against a valve seat to prevent oil passing to the engine. The shut off valve can be incorporated into the filter element (73), into a central support tube (184) of the housing, or into the inlet or outlet fittings (268, 270) for the housing. Supporting structure (174, 218) is provided to maintain thefloat member in a proper orientation. A pressure relief valve (230) can also be provided upstream from the shut-off valve to relieve system pressure when the shut-off valve is closed. |
