Laser control device, laser control system, laser device, and laser control method

Patent metadata

Field	Value
Publication number	US-11293835-B2
Application number	US-202016750717-A
Country	US
Kind code	B2
Filing date	Jan 23, 2020
Priority date	Jan 31, 2019
Publication date	Apr 5, 2022
Grant date	Apr 5, 2022

Abstract

A laser control device includes a processor configured to control, when a control circuit of a laser device detects occurrence of an abnormality in a laser oscillator or a laser optical system and stops laser output from the laser oscillator, the control circuit based on a result of determining whether to enable or disable re-outputting of laser light from the laser oscillator by inputting, to a classifier, input data being at least a part of environmental data and state data about the laser device in a predetermined period including a stop time of laser output. Then, the state data and the input data in the predetermined period include at least one of time-series data about a light amount of laser light and time-series data about a light amount of return light propagating in a direction opposite to a direction of the laser light in the predetermined period.

First claim

What is claimed is:

1. A laser control device that controls a laser device including a laser oscillator that outputs laser light, an output light detector that detects a light amount of laser light output from the laser oscillator, a return light detector that detects a light amount of return light propagating in a direction opposite to a propagation direction of the laser light through a laser optical system including an optical fiber that propagates the laser light, and a control circuit that controls the laser oscillator, the laser control device comprising:
a processor configured to determine, when the control circuit detects occurrence of an abnormality in the laser oscillator or the laser optical system and stops laser output from the laser oscillator, whether to enable or disable re-outputting of laser light from the laser oscillator by inputting input data being at least a part of state data indicating a state of the laser device and environmental data indicating a state of an environment in which the laser device and the optical fiber are installed in a predetermined period including a stop time of the laser output, to a classifier that determines whether to enable or disable re-outputting of laser light from the laser oscillator, based on the input data; and
control the control circuit in accordance with the determination result, wherein
the state data and the input data in the predetermined period include at least one of time-series data about a light amount of the laser light and time-series data about a light amount of the return light in the predetermined period.

2. The laser control device according to claim 1 , wherein the processor is further configured to train the classifier, based on the input data at each of a plurality of the stop times.

3. The laser control device according to claim 2 , wherein the processor is further configured to acquire, for each of the plurality of the stop times, label data indicating that re-outputting of laser light is disabled when damage in the laser oscillator or the laser optical system expands by re-outputting laser light by the laser oscillator after the stop time, and, on the other hand, indicating that re-outputting of laser light is enabled when damage in the laser oscillator and the laser optical system does not expand even by re-outputting laser light by the laser oscillator after the stop time,
wherein the processor trains the classifier in accordance with a supervised learning technique, based on a pair of the input data and the label data at each of the plurality of the stop times.

4. The laser control device according to claim 3 , further comprising:
a breakage device that can break the optical fiber in a predetermined section of the optical fiber,
wherein the processor acquires, as data indicating that re-outputting of laser light is disabled, the label data at a stop time at which occurrence of the abnormality is detected by breaking the optical fiber by the breakage device, among the plurality of the stop times.

5. The laser control device according to claim 2 , wherein the processor is further configured to acquire, for each of the plurality of the stop times, determination data indicating whether or not controlling the laser oscillator by the control circuit is correct in accordance with a determination result of whether to enable or disable re-outputting of laser light, which is output from the classifier, by inputting the input data in the predetermined period including the stop time,
wherein the processor trains, for each of the plurality of the stop times, the classifier in accordance with a reinforcement learning technique, based on the determination data at the stop time, and
it is determined that the determination data is correct, when the determination result indicates that re-outputting of laser light is enabled and damage in the laser oscillator and the laser optical system does not expand even by re-outputting laser light from the laser oscillator, or when the determination result indicates that re-outputting of laser light is disabled and damage in the laser oscillator or the laser optical system expands by re-outputting laser light from the laser oscillator.

6. The laser control device according to claim 2 , further comprising:
a communication circuit configured to be able to communicate with a plurality of the laser devices connected via a first communication network and communicate with another laser control device connected via a second communication network that connects the first communication network to another communication network to which the another laser control device is connected,
wherein the processor trains the classifier, based on the input data acquired via the communication unit from any one or more of the plurality of laser devices connected via the first communication network, and
determines, for each of the plurality of laser devices connected via the first communication network, whether to enable or disable re-outputting of laser light from the laser oscillator of the laser device by inputting the input data acquired from the laser device to the classifier, and
the classifier is shared with the another laser control device.

7. The laser control device according to claim 1 , wherein
the classifier further outputs at least one of a damaged portion and a damage state being estimated in the laser oscillator or the laser optical system when the classifier outputs a determination result indicating that re-outputting of laser light is disabled, and
the processor causes a display device to display the at least one of the damaged portion and the damage state being estimated.

8. The laser control device according to claim 7 , wherein the processor is further configured to train the classifier, based on the input data at each of the plurality of the stop times and the at least one of the damaged portion and the damage state.

9. The laser control device according to claim 1 , wherein
the processor controls the control circuit in such a way as to stop outputting of the laser light when the classifier outputs a determination result indicating that re-outputting of laser light is disabled by inputting the input data in the latest certain period having a length identical to that of the predetermined period to the classifier.

10. The laser control device according to claim 1 , wherein
the laser device shifts to a stop state in which laser output is not restarted when the control circuit stops laser output from the laser oscillator, and
the laser control device further includes
an input device for operating the laser device, and
a stop state release input device that is provided separately from the input device, and receives an operation for releasing the stop state after the control circuit stops laser output from the laser oscillator.

11. A laser control system comprising a laser device, and a laser control device that can communicate with the laser device via a communication network, wherein
the laser device includes:
a laser oscillator that outputs laser light;
an output light detector that detects a light amount of laser light output from the laser oscillator;
a return light detector that detects a light amount of return light propagating in a direction opposite to a propagation direction of the laser light through a laser optical system including an optical fiber that propagates the laser light;
a control circuit that controls the laser oscillator; and
a memory configure to store, when the control circuit detects occurrence of an abnormality in the laser oscillator or the laser optical system and stops laser output from the laser oscillator, input data being at least a part of state d

Assignees

• Fanuc Corp

Inventors

• Miyata Ryusuke
• Takigawa Hiroshi

Classifications

• H01S3/005

  Optical devices external to the laser cavity, specially adapted for lasers, e.g. for homogenisation of the beam or for manipulating laser pulses, e.g. pulse shaping (shaping laser beam for working metal or other materials B23K26/06; optical elements, systems or apparatus in general G02B) · CPC title

• B23K26/0626

  Energy control of the laser beam (B23K26/0622 takes precedence) · CPC title

• H01S3/106

  by controlling devices placed within the cavity ({H01S3/10076,} H01S3/13 take precedence) · CPC title

• H01S3/0014 Primary

  Monitoring arrangements not otherwise provided for (photometry G01J1/00, e.g. G01J1/4257; radiation pyrometry G01J5/00; measuring coherence of light G01J9/00; measuring wavelength of light G01J9/00, e.g. G01J9/0246; measuring optical pulses G01J11/00; calorimetrically measuring power of laser beams G01K17/003) · CPC title

• H01S3/06708

  Constructional details of the fibre, e.g. compositions, cross-section, shape or tapering (optical fibres as passive waveguides G02B6/02) · CPC title