Work machine and operating device for work machine

Patent metadata

Field	Value
Publication number	US-12565755-B2
Application number	US-202318474617-A
Country	US
Kind code	B2
Filing date	Sep 26, 2023
Priority date	Mar 31, 2021
Publication date	Mar 3, 2026
Grant date	Mar 3, 2026

Abstract

A work machine includes an operating device operable in a first direction and a second direction, a hydraulic pump configured to supply hydraulic oil, a hydraulic actuator, a directional control valve configured to control the hydraulic oil flowing from the hydraulic pump to the hydraulic actuator, and a hardware processor configured to control the directional control valve based on the amount of operation of the operating device. The operating device is structured or placed such that a force is likely to escape in the first direction when the operating device is operated in the second direction. The operating device is configured such that a dead area increases with respect to the first direction in which the force is likely to escape.

First claim

What is claimed is:

1 . A work machine comprising:
an operating device including
an operating lever configured to tilt in a first direction, a second direction, a third direction, and a fourth direction, the first direction and the second direction being opposite to each other, the third direction and the fourth direction being opposite to each other;
a cam fixed to the operating lever; and
a first pusher, a second pusher, a third pusher, and a fourth pusher contacting the cam and configured to be pushed by the cam when the operating lever tilts in the first direction, the second direction, the third direction, and the fourth direction, respectively, the first pusher including a single first return spring configured to return the operating lever tilted in the first direction to a neutral position, the second pusher including a single second return spring configured to return the operating lever tilted in the second direction to the neutral position, the third pusher including a single third return spring configured to return the operating lever tilted in the third direction to the neutral position, the fourth pusher including a single fourth return spring configured to return the operating lever tilted in the fourth direction to the neutral position;
a hydraulic pump configured to supply hydraulic oil; a hydraulic actuator; a directional control valve configured to control the hydraulic oil flowing from the hydraulic pump to the hydraulic actuator; and a hardware processor configured to control the directional control valve based on an amount of operation of the operating lever, wherein the hardware processor is configured to set a dead area such that the dead area increases with respect to the first direction and the second direction as the operating lever tilts in the second third direction or the fourth direction, the operating lever is configured to tilt with a maximum operation amount to maximize a spool stroke amount of the directional control valve, and the hardware processor is configured to set the maximum operation amount of the operating lever such that the maximum operation amount in each of the first direction and the second direction decreases as the amount of operation in the third direction or the fourth direction increases.

2 . The work machine as claimed in claim 1 , wherein the hardware processor is configured to set the dead area such that the dead area increases in the first direction and the second direction as the amount of operation increases in the third direction or the fourth direction.

3 . The work machine as claimed in claim 1 , wherein
the first direction and the second direction constitute one of a left-right direction or a front-back direction, and the third direction and the fourth direction constitute the other of the left-right direction or the front-back direction.

4 . The work machine as claimed in claim 1 , wherein
the first direction and the second direction constitute a left-right direction, the third direction and the fourth direction constitute a front-back direction, and the first return spring and the second return spring have a smaller spring constant than the third return spring and the fourth return spring.

5 . The work machine as claimed in claim 1 , wherein the hardware processor is configured to, when the operating lever tilts in one of the first direction or the second direction while the operating lever tilts in one of the third direction or the fourth direction, control the control amount of the directional control valve with respect to said one of the first direction or the second direction based on the maximum operation amount in said one of the first direction or the second direction and the amount of operation in said one of the first direction or the second direction.

6 . The work machine as claimed in claim 1 , wherein
the operating lever has an operable range in which the operating lever is operable, and the maximum operation amount of the operating lever is set within the operable range.

7 . The work machine as claimed in claim 1 , wherein
the hardware processor is configured to set the dead area such that the dead area increases with respect to the third direction and the fourth direction as the operating lever tilts in the first direction or the second direction.

8 . The work machine as claimed in claim 1 , wherein the hardware processor is configured to, when the operating lever tilts in one of the first direction or the second direction while the operating lever tilts in one of the third direction or the fourth direction, control the control amount of the directional control valve with respect to said one of the first direction or the second direction based on a ratio of the maximum operation amount in said one of the first direction or the second direction and the amount of operation in said one of the first direction or the second direction.

9 . The work machine as claimed in claim 1 , wherein a correspondence between the amount of operation of the operating lever in each of the first direction and the second direction and the spool stroke amount of the directional control valve with respect to each of the first direction and the second direction changes according to the amount of operation of the operating lever in the third direction or the fourth direction.

10 . An operating device for a work machine, the operating device comprising:
an operating lever configured to tilt in a first direction, a second direction, a third direction, and a fourth direction, the first direction and the second direction being opposite to each other, the third direction and the fourth direction being opposite to each other; a cam fixed to the operating lever; and a first pusher, a second pusher, a third pusher, and a fourth pusher contacting the cam and configured to be pushed by the cam when the operating lever tilts in the first direction, the second direction, the third direction, and the fourth direction, respectively, the first pusher including a single first return spring configured to return the operating lever tilted in the first direction to a neutral position, the second pusher including a single second return spring configured to return the operating lever tilted in the second direction to the neutral position, the third pusher including a single third return spring configured to return the operating lever tilted in the third direction to the neutral position, the fourth pusher including a single fourth return spring configured to return the operating lever tilted in the fourth direction to the neutral position, wherein a dead area of the operating device is so set as to increase with respect to the first direction and the second direction as the operating lever tilts in the third direction or the fourth direction, the operating lever is configured to tilt with a maximum operation amount to maximize a spool stroke amount of the directional control valve, and the hardware processor is configured to set the maximum operation amount of the operating lever such that the maximum operation amount in each of the first direction and the second direction decreases as the amount of operation in the third direction or the fourth direction increases.

Assignees

• Sumitomo Construction Machinery Co Ltd

Inventors

• Misaki Youji

Classifications

• G05G2505/00

  Means for preventing, limiting or returning the movements of parts of a control mechanism, e.g. locking controlling member · CPC title

• G05G5/05

  Means for returning or tending to return controlling members to an inoperative or neutral position, e.g. by providing return springs or resilient end-stops (G05G5/28 takes precedence) · CPC title

• E02F9/2296

  Systems with a variable displacement pump · CPC title

• E02F9/2292

  Systems with two or more pumps · CPC title

• E02F9/2285

  Pilot-operated systems · CPC title