Multi-joint robot having gas spring, and method for estimating inner pressure of the gas spring

Patent metadata

Field	Value
Publication number	US-9102064-B2
Application number	US-201414228548-A
Country	US
Kind code	B2
Filing date	Mar 28, 2014
Priority date	Mar 29, 2013
Publication date	Aug 11, 2015
Grant date	Aug 11, 2015

Abstract

A multi-joint robot having a function for estimating an amount of decrease in inner pressure of a gas spring, by means of a simple and low-cost structure, and a method for estimating the amount of decrease in inner pressure of the gas spring. The gas pressure within a cylinder of the gas spring decreases in connection with the motion of a lower arm associated with the gas spring. In the present invention, in view of a finding that the amount of decrease in inner pressure has a high correlation with a total movement distance obtained by integrating an amount of back-and-forth motion of a piston rod relative to a cylinder, an amount of decrease in inner pressure within the gas spring is estimated by calculating the total movement distance.

First claim

The invention claimed is:

1. A multi-joint robot comprising:
a robot mechanical unit having at least one arm;
a gas spring arranged on the arm; and
a controller which controls the robot mechanical unit,
wherein the gas spring comprises a cylinder, compressible inert gas enclosed within the cylinder and a piston rod configured to slide in the cylinder, the gas spring being configured as a gas balancer for reducing a load of a servomotor which drives the arm, and
wherein the…

Assignees

• Fanuc Corp

Inventors

• Hayashi Yu

Classifications

• G05B2219/36406

  Physics · mapped topic

• B25J9/1674 Primary

  Operations & Transport · mapped topic

• B25J19/0012

  Operations & Transport · mapped topic