To provide a variable displacement gear pump with low-fuel consumption, by reducing a size and varying a capacity including 0%.
The variable displacement gear pump 101 comprises: D-S short-circuiting passages 21a, 21b connecting discharge-side spaces 62a, 62b with an intake-side space 61; valves 51a, 51b respectively disposed to these passages 21a, 21b and opening/closing the passages 21a, 21b; paths 22a, 22b connecting closing part pressure release holes 12a, 12b to the valves 51a, 51b and opening/closing the valves 51a, 51b by respective pressure; paths 23a, 23b connecting the paths 22a, 22b to the intake-side space 61; and solenoid valves 18a, 18b disposed to the paths 23a, 23b, changing respective pressure by opening/closing the paths 23a, 23b to open/close the valves 51a, 51b.
MURAKAMI KAZURO
YOKOI HIRONAO
SUZUKI SHIGERU
FUJII TOSHIRO
YAMASHITA KATSUMI
Hidetoshi Furukawa
Suzuki Kenchi
Kajinami order
Masahiro Taguchi
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