Patent ID: 11905684
Assignee: KUBOTA CORPORATION
Field: Civil engineering (Other fields)
Classification: CPC E  F | IPC E

Claim 0:
1. A hydraulic system for a working machine, the hydraulic system comprising:
a first hydraulic pump;
a first hydraulic device to be actuated by hydraulic fluid delivered by the first hydraulic pump;
a hydraulic fluid tank to store hydraulic fluid;
a first discharge fluid passage to allow hydraulic fluid discharged from the first hydraulic device to flow into the hydraulic fluid tank;
a second hydraulic pump to suck hydraulic fluid from the hydraulic fluid tank through a suction fluid passage, the second hydraulic pump being connected to the hydraulic fluid tank via the suction fluid passage;
a second hydraulic device to be actuated by hydraulic fluid delivered by the second hydraulic pump, the second hydraulic device being configured such that a difference between a flow rate of hydraulic fluid supplied from the second hydraulic pump to the second hydraulic device and a flow rate of hydraulic fluid discharged from the second hydraulic device changes according to a manner in which the second hydraulic device is actuated;
a second discharge fluid passage to allow hydraulic fluid discharged from the second hydraulic device to flow into the first hydraulic pump, the second discharge fluid passage being connected to a suction port of the first hydraulic pump;
a connecting fluid passage branching off from the second discharge fluid passage and connected to the suction fluid passage; and
a supplier to additionally supply hydraulic fluid to the second discharge fluid passage, the supplier being connected to the second discharge fluid passage, wherein
the supplier is a bypass fluid passage connecting the second discharge fluid passage and the hydraulic fluid tank; and
an inside diameter of the bypass fluid passage is greater than an inside diameter of the connecting fluid passage and an inside diameter of the second discharge fluid passage.