Work machine and method of controlling work machine

Patent metadata

Field	Value
Publication number	US-11142889-B2
Application number	US-201716087776-A
Country	US
Kind code	B2
Filing date	Dec 1, 2017
Priority date	Dec 1, 2017
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

A work machine includes first and second hydraulic motors, first and second hydraulic pumps provided to supply hydraulic oil in correspondence with the first and second hydraulic motors, respectively, first and second swash plate angle sensors provided in correspondence with swash plates which regulate amounts of delivery by the first and second hydraulic pumps, respectively, the first and second swash plate angle sensors each detecting an angle of the swash plate, a delivery amount setting unit which sets an ideal amount of delivery by the first and second hydraulic pumps, and a command value control unit which corrects a command value for adjusting an angle of the swash plate such that the amount of delivery in accordance with a result of detection by the first and second swash plate angle sensors is set to the ideal amount of delivery.

First claim

The invention claimed is:

1. A work machine comprising:
first and second hydraulic motors;
first and second hydraulic pumps provided to supply hydraulic oil in correspondence with the first and second hydraulic motors, respectively;
first and second swash plate angle sensors provided in correspondence with swash plates which regulate amounts of delivery by the first and second hydraulic pumps, respectively, the first and second swash plate angle sensors each detecting an angle of the swash plate;
a delivery amount setting unit which sets an ideal amount of delivery by the first and second hydraulic pumps; and
a command value control unit which corrects a command value for adjusting an angle of the swash plate based on a predefine relationship between the command value for adjusting the angle of the swash plate and an amount of delivery such that the amount of delivery in accordance with a result of detection by the first and second swash plate angle sensors is set to the ideal amount of delivery, wherein
the command value control unit includes:
a command value setting unit which sets a command value for adjusting an angle of the swash plate, and
a command value correction unit which corrects the command value set by the command value setting unit based on the predefine relationship between the command value for adjusting the angle of the swash plate and the amount of delivery such that the amount of delivery in accordance with the result of detection by the first and second swash plate angle sensors is set to the ideal amount of delivery, and wherein

the command value correction unit corrects the command value by referring to a table which predefines the relationship between the command value for adjusting the angle of the swash plate and the amount of delivery.

2. The work machine according to claim 1 , wherein
the command value correction unit corrects the command value when the swash plate is at an angle between a maximum tilt angle and a minimum tilt angle.

3. The work machine according to claim 1 , wherein
the ideal amount of delivery by the first and second hydraulic pumps is set based on a state of operation of a travel control lever.

4. The work machine according to claim 1 , wherein
the first and second swash plate angle sensors each detect an angle between a maximum tilt angle and a minimum tilt angle of the swash plate.

5. A method of controlling a work machine, the work machine including first and second hydraulic pumps provided to supply hydraulic oil in correspondence with first and second hydraulic motors, respectively, first and second swash plate angle sensors provided in correspondence with swash plates which regulate amounts of delivery by the first and second hydraulic pumps, respectively, the first and second swash plate angle sensors each detecting an angle of the swash plate, and a delivery amount setting unit which sets an ideal amount of delivery by the first and second hydraulic pumps, the method comprising:
accepting a result of detection by the first and second swash plate angle sensors; and
correcting a command value for adjusting an angle of the swash plate based on a predefine relationship between the command value for adjusting the angle of the swash plate and an amount of delivery such that the amount of delivery in accordance with the result of detection by the first and second swash plate angle sensors is set to the ideal amount of delivery, wherein
correcting the command value for adjusting the angle of the swash plate includes:
setting a command value for adjusting an angle of the swash plate, and
correcting the set command value based on the predefine relationship between the command value for adjusting the angle of the swash plate and the amount of delivery such that the amount of delivery in accordance with the result of detection by the first and second swash plate angle sensors is set to the ideal amount of delivery, and wherein

the command value is corrected by referring to a table which predefines the relationship between the command value for adjusting the angle of the swash plate and the amount of delivery.

Assignees

• Komatsu Mfg Co Ltd

Inventors

• Ohigashi Koji

Classifications

• B60K6/20

  the prime-movers consisting of electric motors and internal combustion engines, e.g. HEVs · CPC title

• E02F9/2296

  Systems with a variable displacement pump · CPC title

• E02F9/2235 Primary

  including an electronic controller · CPC title

• F04B1/29

  by varying the relative positions of a swash plate and a cylinder block · CPC title

• E02F3/32

  working downwardly and towards the machine, e.g. with backhoes · CPC title