US 12,378,751 B2
Shovel
Kiminori Sano, Chiba (JP); and Ryuji Shiratani, Chiba (JP)
Assigned to SUMITOMO CONSTRUCTION MACHINERY CO., LTD., Tokyo (JP)
Filed by SUMITOMO CONSTRUCTION MACHINERY CO., LTD., Tokyo (JP)
Filed on Sep. 27, 2021, as Appl. No. 17/448,970.
Application 17/448,970 is a continuation of application No. PCT/JP2020/014312, filed on Mar. 27, 2020.
Claims priority of application No. 2019-069171 (JP), filed on Mar. 29, 2019.
Prior Publication US 2022/0010529 A1, Jan. 13, 2022
Int. Cl. E02F 9/22 (2006.01)
CPC E02F 9/2292 (2013.01) [E02F 9/2235 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A shovel comprising:
a lower traveling structure;
an upper swing structure swingably mounted on the lower traveling structure;
an engine mounted on the upper swing structure;
a first hydraulic pump configured to be driven by the engine, the first hydraulic pump being an electrically controlled variable displacement hydraulic pump;
a second hydraulic pump configured to be driven by the engine, the second hydraulic pump being an electrically controlled variable displacement hydraulic pump;
a first regulator configured to control a first geometric displacement of the first hydraulic pump;
a second regulator configured to control a second geometric displacement of the second hydraulic pump; and
processing circuitry configured to electrically control the first and second regulators,
wherein the processing circuitry is configured to
calculate a limit value of the first and second geometric displacements based on respective discharge pressures of the first and second hydraulic pumps,
calculate a first required geometric displacement of the first hydraulic pump and a second required geometric displacement of the second hydraulic pump,
compare the first required geometric displacement with the limit value and compare the second required geometric displacement with the limit value, and
spare the second hydraulic pump part of an available torque allocated to the first hydraulic pump in response to determining, as a result of said comparing, that the second required geometric displacement exceeds the limit value and the first required geometric displacement is less than the limit value.