JP2010094708A - Safety protection system for laser machining - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a safety protection system for laser machining, in which visibility of an operator is improved and operability and safety of the operator are also improved by adopting cableless structure. <P>SOLUTION: The safety protection system for laser machining includes: a light shielding mask 3 including a liquid crystal type light shielding mask 3a and a laser beam shielding plate 3b, on which lead wires are printed; a human body detection sensor 2 for detecting whether a protection helmet 6 equipped with a light shielding mask is mounted; a transmitting part 1a of a radio apparatus 1, which is connected to the light shielding mask and a human body detection sensor: a battery 4 for supplying electric power to the transmitting part; a receiving part 1b for receiving electric waves from the transmitting part; and a main controller 7, which is connected to the receiving part. Breakage information of a lead wire of the laser beam shielding plate and a detected result of the human body detection sensor are transmitted to the main controller through the transmitting part and the receiving part. When the main controller emits a laser oscillation signal, the liquid crystal type light shielding mask is instantly darkened. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a laser processing safety protection system used in a laser processing machine.

  Conventionally, for example, Patent Document 1 discloses a technique in which a plurality of photoelectric sensors are arranged in a commercially available protective helmet as a safety protective device for laser processing, and the wearing is detected by the reflectance of a human body. Further, for example, Patent Document 2 discloses a technique for disposing high-intensity laser light by arranging a laser light-shielding plate in a visual recognition window of a commercially available protective helmet.

Furthermore, for example, the invention of Patent Document 3 discloses an invention in which conductive thin wires are arranged in a plane pattern on a light shielding plate of a commercially available protective helmet to detect light shielding plate breakage (burnout).
Japanese Patent Laid-Open No. 10-225478 Japanese Utility Model Publication No. 4-113176 JP 2001-113386 A

  However, in the invention of Patent Document 1, the sensitivity changes depending on the state of the human body (skin color, hair, etc.) and the wearing state. Further, in the invention of Patent Document 2, when the attenuation rate of the laser light is increased, the brightness at the normal time is lowered and the visibility is deteriorated. Further, during processing, visible light is generated in the spectrum, resulting in extreme brightness. And in invention of patent document 3, there existed a problem that the cable from a control apparatus to a working position obstructed operability, since it was necessary to make a pattern disconnection detection into a normally closed contact and to use a wired line. Therefore, each of the above sensors constitutes a circuit that stops laser oscillation when the conduction is cut off. In either case, the workability is remarkably impaired and the load on the operator is large.

  The present invention has been made to solve the above-described problems, and provides a safety protection system for laser processing in which the visibility of the operator is improved and the operability and safety of the operator by cableless are improved. Objective.

  In order to achieve the above-mentioned object, the present invention comprises the following configurations (1) to (4).

  (1) A light-shielding mask composed of a liquid-crystal-type light-shielding mask and a laser light-shielding plate on which conductive wires are printed; a human body detection sensor for detecting whether or not a protective helmet equipped with the light-shielding mask is attached; A transmitter of a wireless device connected to the mask and the human body detection sensor, a battery for supplying power to the transmitter, a receiver for receiving radio waves transmitted from the transmitter, and the receiver Comprising a connected main control device, the damage information of the conductor of the laser shading plate and the detection result of the human body detection sensor are wirelessly transmitted to the main control device via the transmission unit and the reception unit, and A laser processing safety protection system characterized in that, when the main control device generates a laser oscillation signal, the liquid crystal shading mask is darkened instantaneously.

  (2) The radio system of the above (1), wherein the radio system of the radio apparatus is a 2.4 GHz band spread spectrum system, and the radio apparatus has a modem that normally has a fail-safe communication protocol. Safety protection system for laser processing.

  (3) The human body detection sensor includes a detection probe, a potential adjustment probe, and a sensor, and the negative electrode of the battery is in contact with the human body via the potential adjustment probe. Safety protection system for laser processing.

  (4) When the human body detection sensor is OFF for a predetermined time or more, the main control device stops power supply to the human body detection sensor and performs only the monitoring communication for the return trigger by intermittent communication with the wireless device. The safety protection system for laser processing according to (1), wherein control is performed to perform a power saving mode.

  By having the above-described configuration, the present invention improves both the operability and visibility of the operator, and can provide a safety protection system for laser processing that is superior in terms of safety.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to examples.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[Constitution]
As shown in FIG. 1, the laser processing safety protection system of the present embodiment includes a liquid crystal light shielding mask 3 a, a human body detection sensor 2, a laser light shielding plate 3 b, a wireless device 1, a battery 4, and a main control device 7.

  The liquid crystal shading mask is a solar battery type liquid crystal welding mask that can switch between light and dark with high sensitivity and high speed. A laser shading plate is attached to the back side. The laser light shielding plate is printed with a conductive thin wire to ensure the breakage of the light shielding plate. Hereinafter, the liquid crystal light shielding mask and the light shielding plate are collectively referred to as a light shielding mask unit 3.

  The human body detection sensor 2 detects contact of a human body using a rubber sheet as a detection probe. That is, the capacitance specific to the human body is detected within a specified range. The human body detection sensor includes a detection probe 2a (rubber sheet), a potential adjustment probe 2b (rubber), and a sensor 2c, and is widely wound around the mounting band 5 of the light shielding mask.

  The wireless device 1 wirelessly transmits a sensor signal such as a human body detection sensor or a laser light shielding plate using a specific logic. The transmitter 1a is basically arranged on the light shielding mask side, and the receiver 1b is basically arranged on the main controller side.

  The battery 4 supplies signal power to the transmitter, the human body detection sensor, the laser light shielding plate, and the liquid crystal light shielding mask.

The main control device 7 is incorporated in a processing machine body to which factory power is supplied.
[Operation]
The operation of the laser processing safety protection system of this embodiment will be described with reference to FIG.

<S101>
A laser processing apparatus including a safety protection system for laser processing is prepared, and various safety checks are performed.

<S102>
The battery 4 is driven from the main control device 7 via the wireless device 1, and the entire circuit of the light shielding mask unit 3 and the human body detection sensor 2 is activated.

<S103>
The continuity of the laser light shielding plate 3b is confirmed via the wireless device, and an interlock is set when the wire is disconnected (S105). The conduction signal of the laser light shielding plate functions as a watch dog dedicated to the system (see FIG. 5).

<S104>
The main controller recognizes the establishment of communication. Here, when communication is not established, the interlock is similarly used.

<S106>
By mounting the light shielding mask unit 3, the human body detection sensor 2 outputs a signal, and the main control device 7 recognizes the light shielding surface mounting and permits the operation via the wireless device 1.

<S107>
Laser processing and others are performed. At this time, the high-sensitivity liquid crystal shading mask 3a darkens the liquid crystal during laser processing, and remarkably reduces gaze stress in an appropriate visibility and plasma environment (see FIG. 3).
FIG. 3A shows a state before laser processing is performed, and the liquid crystal shading mask is not darkly turned. FIG. 3B shows a state in which laser processing is performed, and the liquid crystal light-shielding mask is in a dark state. This darkening darkens instantaneously (1/12000 seconds) from the start of laser processing under the control of the main controller. FIG. 3C shows a state during laser processing of only a conventional laser light shielding plate.
In this system, the absence of a cable significantly reduces the burden of mounting, hindering movement during work and accompanying work, and being caught in the cable.

<S108>
At the end of the work, when the shading mask is removed from the human body, the human body detection sensor stops signal output. The main control device prohibits the operation through the wireless device.

[System configuration]
The system configuration of the laser processing safety protection system of this embodiment will be described below.

  When the output of the human body detection sensor is stopped (OFF state) for a predetermined time or longer, the wireless device puts the battery into a power saving state, and therefore waits for a return trigger (see FIG. 4).

  That is, if the human body detection sensor does not turn on for a certain period of time or longer, the power supply to the human body detection sensor is turned off, and the wireless device performs only the monitoring communication of the return trigger from the constant communication to the intermittent communication (ON and OFF at regular intervals). It becomes power saving mode to perform. It returns from the power saving mode by a power saving trigger (button operation or the like in the main controller).

  In addition, when a plurality of protection safety systems for laser processing are independently operated, there is no interference because a different radio frequency is assigned to each system (wireless device) and the direction can be selected.

  The wireless system uses a 2.4 GHz band spread spectrum system that does not require approval related to the Radio Law, uses a modem with high noise resistance, and standard fail-safe in the communication protocol. When communication is impossible, the output contact on the reception processing side is turned off to establish a disconnection state of the B contact.

  This system is assumed to have a wireless safety device based on double safety processing, that is, both a fail-safe of the wireless protocol itself and a fail-safe due to disconnection of the laser shading plate.

  Battery power is indispensable for wireless communication, but by incorporating power-saving software, communication is restored only during use, and battery consumption is reduced. In addition, frequency ch switching is provided for radio-specific interference to support multiple systems.

[Human body detection sensor]
The human body detection sensor 2 is a detection probe that can enable stable capacitance detection when the detection probe 2a and the potential probe 2b are both in contact with the human body in a closed circuit in which a potential is floating. Since the battery potential floats with respect to GND, the battery (−) side is brought into contact with the human body (detected object) which is the GND of the detection circuit, thereby stabilizing the capacitance detection. Stabilization and power saving can be achieved by employing a capacitance type human body detection sensor (see FIG. 6).

[High sensitivity LCD shading mask]
This liquid crystal shading mask increases the visible light transmittance when the liquid crystal is transparent, and lowers the trigger threshold illuminance when the liquid crystal is dark. It is. Based on the protection from the laser light by the high-sensitivity liquid crystal type light shielding surface, the protection from the processing plasma light is made compatible according to the operation state.

  As described above, the safety protection system for laser processing according to the present embodiment provides a protection system in which the operability of the operator of the laser processing machine is remarkably improved, the visibility is improved, and the safety is improved. It becomes possible.

The figure which shows the whole structure of the protector for laser processing of an Example. The flowchart for demonstrating operation | movement of the laser processing protector of an Example. The figure which shows the operation state of the high sensitivity liquid crystal shading mask Diagram showing power saving soft time chart Conceptual diagram showing fail-safe configuration The figure which shows the composition of a human body detection sensor

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Radio | wireless apparatus 1a Transmitter 1b Receiver 2 Human body detection sensor 2a Detection probe 2b Potential adjustment probe 2c Sensor 3 Shading mask unit 3a Liquid crystal shading mask 3b Laser shading plate 4 Battery 5 Wearing band 6 Protective helmet 7 Main controller 8 Laser oscillator 9 Laser torch

Claims (4)

A shading mask comprising a liquid crystal shading mask and a laser shading plate printed with a conductive wire;
A human body detection sensor for detecting whether or not a protective helmet equipped with the light shielding mask is attached;
A transmission unit of a wireless device connected to the light shielding mask and the human body detection sensor;
A battery for supplying power to the transmitter;
A receiving unit for receiving radio waves transmitted from the transmitting unit;
A main controller connected to the receiver,
Damage information on the conductor of the laser shading plate and the detection result of the human body detection sensor are wirelessly transmitted to the main controller via the transmitter and receiver, and the main controller generates a laser oscillation signal. In this case, a safety protection system for laser processing, wherein the liquid crystal shading mask is darkened instantaneously.   2. The laser processing safety according to claim 1, wherein the radio system of the radio apparatus is a 2.4 GHz band spread spectrum system, and the radio apparatus has a modem having a fail-safe standard in a communication protocol. Protection system.   The laser processing safety according to claim 1, wherein the human body detection sensor includes a detection probe, a potential adjustment probe, and a sensor, and the negative electrode of the battery is in contact with the human body via the potential adjustment probe. Protection system.   The main control device, when the human body detection sensor is OFF for a predetermined time or more, stops power supply to the human body detection sensor, and performs only the monitoring communication for the return trigger by intermittent communication with the wireless device. The safety protection system for laser processing according to claim 1, wherein control for setting the mode is performed.

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