To simplify a switching means of a two position direction switching valve of a fluid pressure drive pump.
In a fluid pressure drive pump which comprises the expansion member 3, 4 mounted in the cylinder cases 1, 2, a shaft for connecting the both end parts of the expansion members 3, 4, and a two position direction switching valve 6 for feeding the driving fluid to the cylinder cases 1, 2, and in which the expansion members 3, 4 are expanded and contracted in accompany with the reciprocation of the shaft, the pump comprises a housing 31 in which the shaft is arranged between the ends thereof, a groove part 36 formed on a shaft part of the shaft 35, a cavity part 32 formed in the housing 31, and forming a gap between the housing and the shaft part, and an inlet 33a and the outlets 33b, 33c for force feeding the switching fluid to the cavity part from the outside. A position of the groove part 36 is changed by the reciprocation of the shaft 35, whereby a passage of the switching fluid, is formed between the cavity part 32 and the outlets 33b, 33c, and a cylinder mechanism 30 is constituted so that the fluid is applied to a corresponding side of the two position direction switching valve 6 from the outlets 33b, 33c through the passage.
NAKAZAWA TAKAO
NISHIKATA YASUKATSU
TAKAHASHI NAOMICHI
KAWASHIMA TSUTOMU
HARUNA KK
M I TECHNO KK
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