Robot safety monitor device, and robot safety monitor method

A robot safety monitor device that monitors safety at a time of a tool change of a robot, comprising:

• a displacement receiving portion that receives a command value or an actual displacement value, the command value being output from a robot control device that controls the robot, the command value being a commanded displacement amount of a motor that drives each axis of the robot, the actual displacement value being output from a servo control device that drives each axis;
• a position coordinates calculation portion that calculates position coordinates of a reference point in an actual space of the robot that moves in association with a change in the command value or the actual displacement value, the position coordinates of the reference position based on the command value or the actual displacement value received by the displacement receiving portion;
• a first tool identification information receiving portion that receives first tool identification information which is output from the robot control device, the first tool identification information indicating a present tool as stored by the robot control device;
• a second tool identification information receiving portion that receives second tool identification information for detecting and identifying a tool currently attached to the robot;
• a determination portion that determines whether or not the first tool identification information and the second tool identification information are different by comparing the first tool identification information and the second tool identification information;
• a region setting portion that calculates a safety region if the tool has changed as determined by the determination portion, the safety region including a plurality of three dimensional volumes;
• and
• an emergency stop signal output portion, including a processor, that outputs an emergency stop signal for causing the robot to be in a safe state if it is determined by the determination portion that the first tool identification information and the second tool identification information are different and if the emergency stop signal output portion determines that the position coordinates of the reference point calculated by the position coordinates calculation portion are outside all of the plurality of three dimensional volumes of the safety region set by the region setting portion.