Kabushiki Kaisha Toyota Jidoshokki

Ryosuke Koshizaka

Shinya Yamamoto

Masahiro Kawaguchi

Nobuaki Hoshino

Mamoru Kuwahara

Satoru Kuramoto

Masahiro Inagaki

Yuya Izawa

Osamu Uchiyama

Daisuke Sato

Mika Fujiwara

Kentaro Ishihara

Yoshiaki Fujiwara

A vacuum pump includes a housing assembly having an oil-reservoir chamber in which a lubricating oil is stored; a pair of screw rotors disposed in the housing assembly and engaged with each other; a pair of rotary shafts connected to the rotors, respectively; a plurality of bearings supporting each of the rotary shafts and having an opening; an oil-feed pump for feeding the lubricating oil from the oil-reservoir chamber to the bearing; an oil-circulation passage provided for circulating the lubricating oil from the oil-feed pump to the oil-reservoir chamber through the bearing; a cover provided at the opening of the bearing to close the opening of the bearing with a clearance remained, the cover permitting the lubricating oil to enter the bearing through the clearance; and an oil-escape passage provided adjacent to the bearing for returning to the oil-reservoir chamber the lubricating oil not entering the bearing.

Vacuum pump with improved oil lubrication

A fluid pump system has a cover, a fluid pump and a conduit. An inside of the cover is divided into a main chamber and a sub chamber. The fluid pump is accommodated in the main chamber. The conduit extends from the fluid pump to an outside of the cover through the sub chamber.

Fluid pump system

A vacuum pump having a rotary shaft that is rotated by a drive source has a main pump and a sub pump. The main pump includes a pump chamber and a gas transferring body that is located in the pump chamber. The main pump is driven by the drive source through the rotary shaft for transferring gas to an exhaust space. The sub pump is connected to the exhaust space for partially exhausting the gas from the exhaust space. The sub pump is driven by the same drive source. The displacement volume of the sub pump is smaller than that of the main pump.

Vacuum pump having main and sub pumps

A Roots pump rotates a plurality of rotors by a pair of rotary shafts to draw gas. Each rotary shaft extends through a rear housing member of the Roots pump. An annular shaft seal is fitted around each rotary shaft and is received in a recess formed in the rear housing member. A helical groove is formed in a circumferential side of each rotary shaft. Each helical groove urges oil between the circumferential side of the associated shaft seal and the circumferential wall of the recess to move from a side corresponding to pump chambers toward a gear accommodating chamber when the associated rotary shaft rotates. This preferably prevents oil from leaking to the pump chambers.

Shaft seal structure of vacuum pumps

Growing community of inventors

Kariya, Japan

Ryosuke Koshizaka