Kabushiki Kaisha Fujikoshi

Hiroyoshi Takamori

Takashi Nishimoto

Seiichi Suzuki

A shaft sealing means for use in a hydraulic pump/motor having a rotary shaft rotating within its body, an oil seal fitted in the gap between the rotary shaft and the body for sealing therebetween and between the high and low pressure sides, and a spacer fixed in the gap. The shaft sealing means comprises anti-protrusion means fitted relatively tightly in the gap with its high pressure side surface in close contact with the low pressure side surface of the oil seal for preventing protrusion of the oil seal toward the low pressure side, and anti-friction means inserted in the gap between the anti-protrusion means and the spacer for providing a sliding motion between the anti-protrusion means and the spacer thereby reducing the generation of frictional forces therebetween. This construction eliminates the possibility of damaging the oil seal thereby preventing oil leakage and also resulting in an improved shaft sealing means for use in a high pressure and/or high speed hydraulic pump/motor having a long service life.

Growing community of inventors

Toyama, Japan

Hiroyoshi Takamori