Parkhurst & Oliff
Device for controlling the pressure in the bearings of a roots blower supercharger
 A pressure controlling device for controlling pressure acting on end faces of bearings in a Roots blower type supercharger. An end portion of a shaft having an impeller projects through an inner wall of a housing of the supercharger, and is rotatably supported by a bearing provided outside of the inner wall. An annular space is formed the bearing and the inner wall. The annular space is communicated with the atmosphere through an air passage which is connected to a control valve. The control valve closes for a predetermined period after the engine load becomes higher than a predetermined value. 
Toyota Jidosha Kabushiki Kaisha
F F F
F02B F02B F04C
inventional inventional inventional
Kichiro
Kato