US 12,404,880 B2
Boom control system of work machine
Yosuke Yamagoe, Tokyo (JP)
Assigned to KOMATSU LTD., Tokyo (JP)
Appl. No. 18/274,798
Filed by KOMATSU LTD., Tokyo (JP)
PCT Filed Feb. 4, 2022, PCT No. PCT/JP2022/004521
§ 371(c)(1), (2) Date Jul. 28, 2023,
PCT Pub. No. WO2022/176653, PCT Pub. Date Aug. 25, 2022.
Claims priority of application No. 2021-022390 (JP), filed on Feb. 16, 2021.
Prior Publication US 2024/0102261 A1, Mar. 28, 2024
Int. Cl. F15B 11/044 (2006.01); E02F 9/22 (2006.01)
CPC F15B 11/044 (2013.01) [E02F 9/2203 (2013.01); E02F 9/2207 (2013.01); F15B 2211/3057 (2013.01); F15B 2211/3127 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A boom control system of a work machine comprising a boom, the boom control system comprising:
a boom cylinder that drives the boom and includes a head side oil chamber and a bottom side oil chamber;
a hydraulic pump;
an oil tank;
a first valve that supplies oil from the hydraulic pump to the head side oil chamber and discharges the oil to the oil tank; and
a second valve that supplies oil from the hydraulic pump to the bottom side oil chamber and discharges the oil to the oil tank, wherein
the first valve includes a first opening for discharging the oil in the head side oil chamber to the oil tank,
the second valve includes a second opening for discharging the oil in the bottom side oil chamber to the oil tank, and
the boom control system further comprises a controller that individually controls
an opening degree of the first opening and an opening degree of the second opening, during work including manipulation of the boom and
upon activation of a boom float function adjusts at least one of the opening degree of the first opening and the opening degree of the second opening based on a work mode selected from a plurality of work modes of a work implement including the boom and the boom cylinder.