OPENTECHNICAL PUBLICATION
OT-2026-000003156

Control apparatus for hydraulic excavator

Published: 2026-09-15T19:40:24.239068Z
Permanent URL: https://opentechnical.org/p/OT-2026-000003156
Categories: Industrial Motion & Power Transmission > Fluid Power

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ABSTRACT

Pressure sensors sense a pilot pressure Pa corresponding to the amount of boom
raising operation of a boom operation lever and a pilot pressure Pb
corresponding to the amount of arm pulling operation of an arm operation
lever. When the condition of Pa>Pb is met during the horizontal pulling
operation, the rate of supply of the working fluid to an arm actuating
cylinder is reduced to a rate corresponding to the amount of operation of the
operation lever. Conversely, when the condition Pa<Pb is met, the rate of
supply of the working fluid to the boom actuating cylinder 5 is reduced to a
rate corresponding to the amount of operation of the operating lever.
Horizontal pulling operation for levelling the ground can be conducted without
requiring high level of skill. The horizontal pulling work can be done easily
and smoothly, while preventing the bucket from cutting into the ground and
from floating above the ground.

1. Drawings

[0001] Sheet 1.

[0002] Sheet 2.

[0003] Sheet 3.

[0004] Sheet 4.

[0005] Sheet 5.

[0006] Sheet 6.

[0007] Sheet 7.

[0008] Sheet 8.

[0009] Sheet 9.

[0010] Sheet 10.

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OpenTechnical publication OT-2026-000003156
Published 2026-09-15T19:40:24.239068Z
https://opentechnical.org/p/OT-2026-000003156