Work machine

Patent metadata

Field	Value
Publication number	US-11879233-B2
Application number	US-201917054797-A
Country	US
Kind code	B2
Filing date	Jun 7, 2019
Priority date	Sep 14, 2018
Publication date	Jan 23, 2024
Grant date	Jan 23, 2024

Abstract

A work machine includes a plurality of actuators that drive a work device; a posture sensor that senses postural data about the work device; and a controller having a degree-of-proximity calculating section that computes a degree of proximity that is an index value indicating proximity between an intrusion prohibition region and the work device on the basis of positional data about the intrusion prohibition region and the postural data. A command section executes, when the proximity specified by the degree of proximity is closer than proximity specified by a degree-of-proximity threshold, operating area limiting control to decelerate at least one of the plurality of actuators such that an intrusion of the work device into the intrusion prohibition region is prevented. History of the data about the degree of proximity calculated at the degree-of-proximity calculating section is stored and the degree-of-proximity threshold is altered on the basis of the history data.

First claim

The invention claimed is:

1. A work machine comprising:
a work device installed on a machine main body;
a plurality of actuators that drive the machine main body and the work device;
a posture sensor that senses postural data about the machine main body and the work device; and
a controller that computes a degree of proximity that is an index value indicating proximity between a preset intrusion prohibition region, and the work device and the machine main body on a basis of positional data about the intrusion prohibition region and the postural data, and when the proximity specified by the degree of proximity is closer than proximity specified by a degree-of-proximity threshold set as a threshold for the degree of proximity, executes operating area limiting control to decelerate at least one of the plurality of actuators such that an intrusion of the work device and the machine main body into the intrusion prohibition region is prevented,
the work machine further comprising a storage device that stores history data about the degree of proximity computed by the controller,
the controller altering the degree-of-proximity threshold on a basis of the history data about the degree of proximity stored in the storage device,
the degree of proximity being a distance between the work device and the machine main body, and the intrusion prohibition region,
the controller executing the operating area limiting control when the distance is shorter than the degree-of-proximity threshold, and lowers the degree-of-proximity threshold as dispersion of the distance decreases.

2. The work machine according to claim 1 , wherein
the storage device stores operability data indicating whether or not operation of the work machine by an operator is enabled, and
when it is checked on a basis of the operability data that operation of the work machine by the operator is temporarily disabled, the controller alters the degree-of-proximity threshold to a value specifying proximity closer to the intrusion prohibition region.

3. The work machine according to claim 1 , wherein
the storage device stores the number of times the degree of proximity to the intrusion prohibition region has become higher than the degree-of-proximity threshold, and
when the number of times has reached a predetermined number of times, the controller alters the degree-of-proximity threshold to a value specifying proximity closer to the intrusion prohibition region.

Assignees

• Hitachi Construction Mach Co

Inventors

• Narikawa Ryu
• Sakamoto Hiroshi
• Moriki Hidekazu

Classifications

• E02F9/2033 Primary

  Limiting the movement of frames or implements, e.g. to avoid collision between implements and the cabin (sub-groups of E02F3/431 of E02F3/435 take precedence; for turntables E02F9/123) · CPC title

• E02F9/2271

  Actuators and supports therefor and protection therefor · CPC title

• E02F9/24

  Safety devices {, e.g. for preventing overload (E02F9/226 takes precedence)} · CPC title

• E02F9/265 Primary

  with follow-up actions (e.g. control signals sent to actuate the work tool) · CPC title

• E02F3/32

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