Hitachi Astemo Ltd.

Hitachi Automotive Systems Steering, Ltd.

Tomohiko Nakazono

Yukio Uchida

Satoshi Muramatsu

A pump device includes: a drive shaft; a pump element; a pump housing including; a pump element receiving space, first and second bearing receiving spaces, a suction passage, a discharge passage, a return passage, and a seal receiving space, a first bearing including a first lubrication groove, received within the first bearing receiving space, and supporting the drive shaft; a second bearing which includes a second lubrication groove having a sectional area that is perpendicular to the rotation axis, and that is greater than a sectional area of the first bearing that is perpendicular to the rotation axis, which is received within the second bearing receiving space, and which supports the drive shaft; and a seal member provided within the seal receiving space, and arranged to seal between the drive shaft and the pump housing.

Pump device

A tank-integrated pump unit includes a reservoir tank fixed to a pump body. The body of the reservoir tank includes an introduction opening for introducing working fluid from an external hydraulic device into the body. A filter member is arranged in the body for filtering working fluid introduced through the introduction opening. A suction passage connection portion is connected to a suction hole of a pump body. The suction passage connection portion includes a body-side opening through a wall of the body. The body-side opening is located below a predetermined level of working fluid and above a lowermost position in the body. A pressure chamber is defined in the body, and located below the body-side opening of the suction passage connection portion. The introduction opening faces the pressure chamber. The filter member covers an upper side of the pressure chamber.

Growing community of inventors

Fujisawa, Japan

Tomohiko Nakazono