JP2000252551A - Laser apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent break of a shutter or deterioration and damage to components within the apparatus. SOLUTION: A control circuit 9 outputs an activation signal D to a drive circuit 8 before driving a laser oscillator 2. In response to a signal D, the circuit 8 outputs an activation current which is a DC current and thereafter a holding current which is a pulse current to a rotary solenoid 6. As a result, the solenoid 6 is excited to thereby move a shutter 5 to an opening position and hold the shutter 5 there under a power-saving state, whereby a radiation window is opened. By driving the oscillator 2 under this state, a laser beam is radiated from the window. When the holding current is reduced to thereby cause the shutter 5 to get out of the opening position, a photo interrupter 7 detects such a state. Thus, the circuit 9 outputs the signal D again. As a result, the shutter 5 is moved to return to the opening position immediately.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser device having a shutter for blocking laser light from a laser oscillator from being emitted to the outside.

[0002]

Conventionally, a laser mark device for performing marking by irradiating a laser beam from a laser oscillator onto a surface of an object such as a work in a condensed state has been practically used. In such a laser marking device, the laser beam path is closed by a shutter while the laser oscillator is stopped because the output of the laser beam is large, preventing the laser beam from being inadvertently emitted. I am trying to do it.

[0003] Generally, such shutter opening and closing drive is performed by driving a solenoid. In this case, when the solenoid is not energized, the shutter is moved to the closed position by the biasing force of the built-in return spring,
During operation of the laser oscillator, the solenoid must be continuously energized to move and hold the shutter at the open position against the return spring, so that the current consumption of the laser marking device increases by the energizing current.

Therefore, when starting the solenoid, a large starting current is supplied to improve the responsiveness of the shutter opening operation.
After the operation, a minimum necessary holding current necessary to hold the shutter at the open position is supplied. As a method of saving power by suppressing the holding current in this way, it is general to apply a starting current consisting of DC to the solenoid at the time of starting, and then to apply a holding current consisting of pulse current.

However, when the holding current is suppressed to the minimum necessary to enhance the power saving effect as described above, the power saving effect is increased, but the temperature characteristics of the solenoid or the variation in the characteristics, and further, the power supply If the holding current fluctuates below the required minimum due to temperature characteristics, there is a possibility that the excitation of the solenoid is stopped and the shutter is closed by the urging force of the return spring.

When the shutter is closed while the laser light is being emitted as described above, not only the laser light is not irradiated onto the object, but also the shutter is damaged, or the internal parts of the apparatus due to the laser light reflected by the shutter. Has the disadvantage that it is deteriorated or damaged.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to reduce the current consumption and prevent the shutter from being damaged even when the shutter is inadvertently closed while the laser oscillator is being driven. Another object of the present invention is to provide a laser device capable of preventing components inside the device from being deteriorated or damaged.

[0008]

According to the present invention, there is provided a shutter provided movably between a closed position in which a laser beam path from a laser oscillator is blocked and an open position in which the laser beam path is opened. Opening and closing means for moving the shutter to the closed position in the biased state and moving the shutter to the open position in the energized state against the biasing force; and When a start current required to move the shutter to the open position is supplied, a holding current required to hold the shutter at the open position is supplied, and when a stop command is given, the holding current is reduced. A driving unit for stopping the energization, and a start command to the driving unit before the laser oscillator is driven and a stop finger for the driving unit after the laser oscillator is stopped. And a control means for detecting that the shutter has exited from the open position, and the control means controls the shutter by the detection means in a driving state of the laser oscillator. When it is detected that the vehicle has exited from the open position, a start command is again given to the driving means (claim 1).

According to such a configuration, when power is not supplied to the opening / closing means, the opening / closing means keeps the shutter in the closed position by the urging force. When the laser oscillator is driven, the control means gives a start command to the driving means before the laser oscillator is driven. As a result, the driving means supplies a starting current necessary for moving the shutter to the open position to the opening / closing means, so that the opening / closing means is activated and moves the shutter from the closed position to the open position against the urging force. . After that, the driving means supplies the opening / closing means with a holding current necessary for holding the shutter in the open position, and the shutter is held in the open position by the opening / closing means. Therefore, by driving the laser oscillator in this state, laser light from the laser oscillator can be emitted to the outside. At this time, since a small holding current is applied to the opening / closing means, the shutter can be held at the open position in the power saving state.

If the holding current supplied from the driving means to the opening / closing means fluctuates and drops, the holding state of the shutter at the open position by the opening / closing means is released, and the attachment of the opening / closing means is released. The shutter may move out of the open position due to the force. In such a case,
Since the detection means detects that the shutter has exited from the open position, the control means gives the drive means a start command again according to the detection result of the detection means.

Accordingly, the driving means again applies the starting current necessary for moving the shutter to the opening position to the opening / closing means, so that the opening / closing means moves the shutter which has exited from the opening position to the opening position. Thus, the shutter immediately returns to the holding state at the open position.

In the above configuration, the opening / closing means may be a solenoid, and the driving means may supply a holding current composed of a pulse current to the solenoid after supplying a starting current composed of a direct current to the solenoid. Item 2).

According to such a configuration, when the shutter is moved to the open position, the driving means is supplied with a starting current composed of direct current to the solenoid, so that a large starting current is applied to the solenoid to close the shutter. Move from the position to the open position against the biasing force. Thereafter, since a holding current composed of a pulse current is supplied from the driving means to the solenoid, a small starting current is applied to the solenoid, and the shutter continues to move to the open position against the urging force. Thereby, power saving can be achieved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a laser mark device will be described below with reference to the drawings. FIG. 2 schematically shows a cross section of the laser mark device. In FIG. 2, a laser oscillator 2 is built in a laser mark device 1 as a laser device, and a laser beam emitted from the laser oscillator 2 is adjusted to an arbitrary emission angle by a carbano mirror 3 in an emission window. 4 illuminated. The laser light is applied to the work in a state where the laser light is focused on a minute point by a lens (not shown). Therefore, by controlling the swinging position of the galvanometer mirror 3, the laser beam condensing position on the work can be moved to perform laser marking.

Here, the shutter 5 corresponding to the emission window 4
Is provided. The shutter 5 is attached to a shaft 6a of a rotary solenoid (corresponding to opening / closing means) 6, and the shutter 5 rotates according to the rotation of the shaft 6a. In this case, the shaft 6a of the rotary solenoid 6 is held at a predetermined reference angle by the biasing force of the built-in return spring, and the shutter 5 closes the emission window 4 completely while the shaft 6a is held at the reference angle. The position is located.

The shutter 5 is provided integrally with a tongue piece 5a (see FIG. 4), and a photo interrupter (corresponding to a detecting means) 7 is provided corresponding to the rotation locus of the tongue piece 5a. ing. This photo-interrupter 7 has a shutter 5
Is to detect that has exited the closed position,
The detection signal C (see FIG. 1) is output when the tongue piece 5a of the shutter 5 is retracted from the optical axis of the photo interrupter 7. In this case, the photo interrupter 7
Is desirably arranged to detect that the shutter 5 has slightly exited from the open position.

FIG. 1 is a block diagram showing an electrical configuration. In FIG. 1, the rotary solenoid 6 is driven by a drive circuit (corresponding to drive means) 8. The drive circuit 8 drives the rotary solenoid 6 by outputting a drive signal A. The drive signal A is composed of a starting current composed of a direct current and a holding current composed of a pulse current, and the holding current has a lower current level than the starting current. In this case, the driving circuit 8
Is configured to output a holding current and output a holding signal B to the control circuit 9 at a predetermined timing after outputting the starting current as the driving signal A. The timing at which the drive signal A switches from the starting current to the holding current may use the detection signal C from the photo-interrupter 7 or set a timer time in advance.

A control circuit (corresponding to control means) 9 drives the laser oscillator 2 by outputting a drive signal E to the laser oscillator 2 in response to a start-up command from the operation unit 10. In such a case, a start signal D is output to the drive circuit 8 prior to the drive. In this case, the control circuit 9 continues the output state of the start signal D until the holding signal B is input from the drive circuit 8.

Here, the control circuit 9 outputs the start signal D to the drive circuit 8 when the detection signal C is input from the photo-interrupter 7 while the drive signal E is output to the laser oscillator 2. Has become.

When stopping the laser oscillator 2, the control circuit 9 stops outputting the drive signal E to the laser oscillator 2 and then outputs a stop signal F to the drive circuit 8. Then, the drive circuit 8 stops outputting the drive signal A to the rotary solenoid 6 in response to the input of the stop signal F.

Next, the operation of the above configuration will be described. When irradiating a laser beam from the laser marking device 1 to perform a marking process on the surface of the work, the work is positioned so that the surface of the work is located at a predetermined position. Then, the operation unit 10
Is operated, the control circuit 9 first outputs a start signal D to the drive circuit 8 (see FIG. 3D).

When the drive circuit 8 receives the start signal D,
The drive signal A is output to the rotary solenoid 6. At this time, when the rotary solenoid 6 is started, the drive circuit 8 outputs DC starting power as the drive signal A (FIG. 3).
(See (a)). As a result, a large starting current flows through the rotary solenoid 6 to be excited, so that the rotary solenoid 6 moves the shutter 5 from the closed position to the open position against the urging force of the return spring as shown in FIG. Become. Then, when the rotary window 6 is completely excited and the emission window 4 closed by the shutter 5 is opened, the drive circuit 8 sends the drive signal A to the minimum necessary to hold the rotary solenoid 6 in the excited state. Is switched to the holding current composed of the pulse current of

When the drive signal A switches from the starting current to the holding current, the holding signal B indicating that the rotary solenoid 6 is excited by the holding current is output from the drive circuit 8 to the control circuit 9 (FIG. 4). 3 (b)).

Therefore, when the control circuit 9 receives the hold signal B, it determines that the shutter 5 is held at the open position and outputs the drive signal E to the laser oscillator 2 (FIG. 3).
(E)). As a result, the laser oscillator 2 is driven and the laser light is emitted through the emission window 4, so that the laser light is irradiated on the surface of the work while being focused on a minute point by a lens (not shown). In this irradiation state, the control circuit 9 controls the swinging position of the galvanomirror 3 to move the laser light condensing position, so that characters,
Numbers, figures, etc. can be marked.

Incidentally, the holding current may fluctuate due to the temperature characteristics of the rotary solenoid 6, or variations in the characteristics, and the temperature characteristics of the power supply. In such a case,
When the holding current given to the rotary solenoid 6 falls below the minimum necessary for keeping the shutter 5 at the open position, the excitation of the rotary solenoid 6 is stopped. The return angle returns to the reference angle due to the biasing force of the return spring, and the shutter 5 returns regardless of the driving state of the laser oscillator 2.
May return to the closed position.

Therefore, in the present embodiment, the shutter 5 is prevented from being located at the closed position when the laser oscillator 2 is driven as follows. That is, when the excitation of the rotary solenoid 6 is stopped, the tongue piece 5a of the shutter 5 retreats from the photo interrupter 7 (see FIG. 5), and the detection signal C is output from the photo interrupter 7 (see FIG. c)).

Here, the control circuit 9 determines whether or not the detection signal C is input from the photo-interrupter 7 in a state where the drive signal E is output to the laser oscillator 2. When the detection signal C is input, Then, regardless of the operation state of the laser oscillator 2, it is determined that the shutter 5 has exited from the open position, and the activation signal D is output to the drive circuit 8 again (see FIG. 3D).

When the start signal D is input, the drive circuit 8
Since the drive signal A is switched from the holding current consisting of a pulse current to the starting current consisting of a direct current again and output, a large starting current is given to the rotary solenoid 6. As a result, the rotary solenoid 6 is immediately excited, and the shutter 5 returns to the open position. Therefore, even if the shutter 5 is inadvertently withdrawn from the open position while the laser light is being emitted, the shutter 5 immediately returns to the open position. This is also a very short time, and the shutter 5 is not damaged, and the components inside the apparatus reflected by the shutter 5 are not deteriorated or damaged.

When the control circuit 9 receives a stop command from the operation unit 10, the control circuit 9 stops outputting the drive signal E output to the laser oscillator 2 and then outputs a stop signal F to the drive circuit 8. Accordingly, the output of the drive signal A given from the drive circuit 8 to the rotary solenoid 6 stops. Thereby, the emission window 4 is closed by the shutter 5 in a state where the emission of the laser light from the laser oscillator 2 is stopped, so that the careless laser light from the laser oscillator 2 is cut off by the shutter 5 thereafter. Is done.

According to the present embodiment, when the laser oscillator 2 is driven, the shutter 5 is held at the open position,
If the holding current of the rotary solenoid 6 is insufficient in the holding state and the shutter 5 moves out of the open position, the rotary solenoid 6 is restarted, so that the shutter 5 immediately returns to the open position. Become like Therefore, unlike the conventional configuration in which the shutter is located at the closed position when the holding current of the solenoid is insufficient, the shutter 5 is damaged or the internal equipment is deteriorated by the influence of the laser light reflected from the shutter 5. A defect such as breakage or breakage can be prevented beforehand.

The present invention is not limited to the above embodiment, but can be modified or expanded as follows. The photo interrupter 7 is not limited to the one that detects the state in which the shutter 5 is closed, and may be one that outputs a detection signal when the shutter 5 is opened. The means for detecting the opening / closing of the shutter 5 is not limited to the photo interrupter 7, but may be a reflective photoelectric sensor, a proximity sensor, a limit switch, or the like. As a means for rotating the shutter, a general solenoid may be used instead of the rotary solenoid, or the shutter may be reciprocated by the solenoid. The present invention is not limited to the laser mark device, and may be applied to a general-purpose laser device.

[0032]

As is apparent from the above description, according to the laser apparatus of the present invention, when the shutter leaves the open position where the laser beam path is opened in the driving state of the laser oscillator, a start command is issued to the opening / closing means. By giving the shutter again, the shutter is moved and returned again to the open position, so that it is possible to prevent the shutter from being damaged, or the components inside the apparatus from being deteriorated or damaged while suppressing the current consumption. It has an excellent effect that it can be done.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an electrical configuration showing an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a mechanical configuration.

FIG. 3 is a diagram showing output timing of each signal.

FIG. 4 is a perspective view of a shutter shown in a state where the shutter is moved to an open position.

FIG. 5 is a perspective view of the shutter shown in a state where the shutter has been retracted from an open position.

[Explanation of symbols]

1 is a laser mark device (laser device), 2 is a laser oscillator, 4 is an emission window, 5 is a shutter, 6 is a rotary solenoid (opening / closing means), 7 is a photo interrupter (detecting means), and 8 is a driving circuit (driving means). , 9 are control circuits (control means).

Claims (2)

[Claims] 1. A shutter movably provided between a closed position in which a laser beam path of a laser oscillator is blocked and an open position in which the laser beam path is opened, and biases the shutter to the closed position in a non-energized state. Opening / closing means for moving the shutter to the open position in the energized state against the urging force in the energized state, and moving the shutter to the open position when the start command is given. A driving means for supplying a holding current necessary for holding the shutter at the open position after supplying a starting current necessary for the power supply and stopping the supply of the holding current when a stop command is given; Control means for giving a start command to the driving means before the laser oscillator is driven and for giving a stop command to the driving means after the laser oscillator is stopped. In the laser apparatus, a detection unit that detects that the shutter has exited from the open position is provided, and the control unit is configured to detect that the shutter has exited from the open position by the detection unit in a driving state of the laser oscillator. A laser device which, when detected, gives a start command to the driving means again. 2. The device according to claim 1, wherein the opening / closing means is a solenoid, and the driving means supplies a holding current composed of a pulse current to the solenoid after supplying a starting current composed of a direct current to the solenoid. Laser device.