Advics Co., Ltd.

Denso Corporation

Nippon Soken, Inc.

Takashi Hashiba

Naoki Hakamada

Tomoaki Kawabata

Takahiro Naganuma

Kazunori Uchiyama

Kunihito Ando

A gear pump apparatus includes a gear pump and a sealing mechanism which includes an annular rubber member, an outer member, and an inner member. One of the outer member and a casing of the gear pump apparatus has a contact member located outside a portion of the outer member which contacts the gear pump in a radial direction of the gear pump. The contact member is placed to create a physical contact between the outer member and the casing to absorb a part of force by which the outer member is pressed against the gear pump. This results in a decrease in pressure acting on an area of contact between the outer member and the gear pump, which leads to a drop in resistance to sliding between the gear pump and the outer member, thus decreasing a loss of torque required for the pumping operation of the gear pump.

Sealing of a gear pump

A gear pump apparatus is equipped with a pump and a sealing mechanism which is made up of an outer member, an inner member, and a rubber member fit between the outer and inner members. The inner member has a pressure-exerted surface to which pressure, as produced by contact of the rubber member with the inner member arising from application of discharge pressure of the pump, is applied. The pressure-exerted surface has a flange which creates thrust to move the inner member away from the gear pump, thereby bringing the inner member against an inner wall of a pump casing to develop a hermetical seal between a high-pressure region and a low-pressure region within the pump casing. This eliminates the leakage of pressure and ensures torque required for a pumping operation of the pump.

Compact structure of gear pump designed to minimize loss of pumping torque

Growing community of inventors

Nishio, Japan

Takashi Hashiba