To provide a hydraulic circuit which can restrain a power consumption as much as possible without causing a useless work in a hydraulic pump to achieve an energy saving, and can miniaturize the hydraulic pump.
A first and a second hydraulic pumps 1, 2 are provided. A hydraulic fluid discharged from the first hydraulic pump 1 is introduced to a first discharge passage 4, which communicate with a main gallery 8. A hydraulic fluid discharged from the second hydraulic pump 2 is introduced to a second discharge passage 14, which communicates with a valve control device 19. A communicating passage 20 to make the first and the second discharge passage 4, 14 mutually communicate is provided. The communicating passage 20 is provided with a relief valve 21 to open the communicating passage 20 under a fixed pressure in the second discharge passage 14.
KONDO TAKEHISA
WATANABE YASUSHI
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