JPH05218531A - Shutter mechanism of laser oscillator - Google Patents

Abstract

PURPOSE:To operate a shutter mechanism performing cut-off and cut-off release of a laser optic axis at a high speed. CONSTITUTION:A shutter plate 1 cutting off a laser optic axis 2 by clockwise turning operation and releasing said cut-off by anticlockwise turning operation is journalled for turning. In addition to turning drive of the shutter plate right and left by the coils 5a, 5b as well as a coil 31, the shutter plate 1 performs turning drive by means of the coils 6a and 6b as well as a coil 32. An open sensor 7 and a closed sensor 8 detect a turning angle of the shutter plate 1 in the cut-off state and in the cut-off release state of the optic axis 2. According to this detected turning angle, a driving direction by means of the coil 6a or the like is made a reverse direction of the driving direction by means of the coil 5a or the like. Accordingly, owing to the drive by means of a magnetic circuit, switching operation can be performed at high speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shutter mechanism, and more particularly to a shutter mechanism for blocking and releasing the optical axis of laser oscillation light in a laser oscillator.

[0002]

2. Description of the Related Art Generally, a solid-state laser using a Q-switch modulator is known to output a pulse having an extremely high peak output value, and is applied to various fields such as a marking device and a trimming device.

For example, when applied to a marking device,
When the repetition frequency of the Q switch pulse is 2 [KHZ] or more, the peak value of the first Q switch pulse that turns the laser beam from the OFF state to the ON state is large, leaving a deep and large machining locus only at this point. Therefore, the work piece may be damaged or the substrate may be damaged.

Therefore, as a conventional method for controlling the peak pulse, a shutter mechanism utilizing a drive source such as a rotary solenoid outside the laser resonator is known. This shutter mechanism will be described with reference to FIG. Figure 3
In (a), an output mirror 33 is provided at one end of the YAG rod 34, and a Q switch 36 and a total reflection mirror 37 are provided at the other end via a shutter mechanism 35. Then, the shutter mechanism 35 is opened and closed to interrupt and release the laser optical axis.

In such a configuration, the shutter mechanism 35 is opened after the pulse oscillation in the Q switch 36, and the portion where the peak pulse is high is deleted for processing. Further, the continuous wave solid-state laser is applied to a marking device, a welding device, etc., and the on / off control of laser light is controlled by the shutter mechanism 3.
5 is done.

Here, the shutter mechanism 35 is shown in FIG.
As shown in FIG.
And a shutter plate 30. When the lead wire 39 is energized by a power source (not shown), the shaft of the rotary solenoid 38 is rotated by the coil and the rotor, which causes the shutter plate 30 to move as indicated by arrow Y.
Therefore, the shutter plate 30 blocks (or cancels) the laser optical axis.

When the current is cut off in this energized state,
A return spring attached to the shaft of the rotary solenoid 38 causes the shaft to rotate in the reverse direction, and the shutter plate 30 returns to its original state. In this way, the interruption (or interruption) of the laser optical axis is performed.

However, the conventional shutter mechanism using this rotary solenoid has a delay time in mechanical operation and a delay time in electrical control, and thus it is difficult to perform high-speed operation with rapid repetition. For this reason, there is a drawback in that it becomes a factor that reduces the processing capability of the application device that controls the on / off of the laser oscillation light.

[0009]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional drawbacks, and an object of the present invention is to provide a shutter mechanism capable of high-speed operation.

[0010]

The shutter mechanism of the present invention is a shutter mechanism for blocking and releasing the optical axis of laser oscillation light in a laser oscillator, and is rotatably supported in first and second directions. A shutter plate that shuts off the optical axis by a turning operation in a first direction and releases the shutoff of the optical axis by a turning operation in a second direction; and a shutter plate that opens the shutter plate in response to an external command. And a magnetic circuit which is rotationally driven in the first and second directions.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a schematic configuration diagram of an embodiment of a shutter mechanism according to the present invention. In the figure, the shutter mechanism of the present embodiment is different from the conventional one in that both the shutter opening operation and the shutter closing operation are rotationally driven by a magnetic circuit. That is, in this example, a magnetic circuit is configured by the drive coils 5a and 5b and the shutter coil 31, and this magnetic circuit drives the shutter plate 1 to rotate right and left around the fulcrum 11 as shown by an arrow Y, and the drive coils 6a and Another magnetic circuit is constituted by 6b and the shutter coil 32, and this magnetic circuit drives the shutter plate 1 to rotate left and right around the fulcrum 11 as indicated by arrow Y.

The shutter plate 1 is rotatably supported by a fulcrum 11. Then, the shutter plate 1
When is closed, the laser beam is stopped and blocked at the position of the laser optical axis 2 (broken line portion). On the other hand, a constant low current is supplied to the shutter coils 31 and 32 from the control circuit 4, and the drive coil 5a
And 5b, or the magnetic poles of either one of the drive coils 6a and 6b, and are not affected by external vibrations. The output of the control circuit 4 is connected to the coil 31, and the output thereof is connected to the coil 32.

In the drive coils 5a and 5b and the drive coils 6a and 6b, the shutter coil 31,
The magnetic poles on the 32 side are connected so as to always have the same polarity and connected to the control circuit 4.

Further, the present shutter mechanism is provided with an open sensor 7 and a close sensor 8 for detecting the rotation angle of the shutter plate 1 in order to detect the open / closed state of the shutter. Both of these sensors are connected to the control circuit 4. Known sensors including a light emitting unit and a light receiving unit may be used for these sensors.

The control circuit 4 is connected to a power supply circuit 9 for operating each coil and the control circuit 4, and a switch circuit 100 for transmitting a control signal 10 for instructing opening / closing of a shutter.

The operation of each part when the control signal 10 changes from the closed state to the open state and vice versa in such a configuration will be described with reference to FIG.

FIG. 2 shows the control signal 10 from the switch circuit 100, the detection signals of the closing sensor 8 and the opening sensor 7, the current flowing through the shutter coils 31 and 32, and the driving coils 5a and 5b, 6a and 6b. The flowing current is shown.

In the figure, when the control signal 10 changes from the closed state to the open state, the control circuit 4 causes the shutter coil 3 to move.
The current to 1, 32 becomes a high current and the magnetic force increases. Further, the drive coils 5a and 5b, the drive coils 6a and 6b
Also, a current is applied so that the magnetic poles at both ends become the same magnetic pole, and the shutter plate 1 moves the fulcrum 11 using the bearing by the attractive force and repulsive force of the magnetic field generated by the shutter coil and the drive coil. Rotate around the open sensor 7 side (left).

The shutter plate 1 starts to rotate and the open sensor 7
When the shutter plate 1 is detected by the control circuit 4, the current applied to the shutter coils 31 and 32 by the control circuit 4 decreases, and the current becomes low.

The drive currents of the drive coils 5a and 5b are turned off by a timer in the control circuit 4 after a certain time delay.
At the same time, a current having a polarity opposite to that at the start of driving is applied to the drive coils 6a and 6b. As a result, the braking effect is generated, and the vibration generated in the shutter plate 1 is suppressed.

The current applied to the drive coils 6a and 6b has a reverse flow after the open sensor 7 is detected, but the current is gradually reduced by the control of the control circuit 4. Therefore, finally, the magnetic force of the shutter coil causes a stable state at the open position.

Next, when the control signal 10 changes from the open state to the closed state, the control circuit 4 causes the control circuit 4 to increase the current to the shutter coils 31 and 32 to increase the magnetic force, as in the case described above. As for the drive coils 5a and 5b and the drive coils 6a and 6b, the shutter plate 1 is close to the close sensor 8 centering on the fulcrum 11 due to the magnetic fields generated by the shutter coils and the drive coils, as in the case described above. (right)
Turn to.

The shutter plate 1 starts to rotate and the closing sensor 8
When the shutter plate 1 is detected by, the current applied to the shutter coils 31 and 32 by the control circuit 4 decreases and becomes a low current.

In the drive coils 5a and 5b, the drive current is turned off after a certain time delay by the timer in the control circuit 4, as in the case described above. At the same time, a current having a polarity opposite to that at the start of driving is applied to the drive coils 6a and 6b. As a result, similarly to the case described above, the braking effect is generated and the vibration generated in the shutter plate 1 is suppressed.

Further, as in the case described above, the drive coil 6
The currents applied to a and 6b are
Although the current flow is reversed, the current is gradually reduced by the control of the control circuit 4. Therefore, finally, the magnetic force of the shutter coil causes a stable state at the closed position.

By performing the control as described above, the high-speed opening / closing operation of the shutter becomes possible.

In the above-described embodiment, the shutter plate is rotationally driven by using two magnetic circuits, but even if one magnetic circuit is used, it is not mechanically driven unlike the conventional shutter mechanism. The shutter can be opened and closed at high speed. If it is necessary to suppress the vibration generated on the shutter plate, 2
The above-mentioned control may be performed using one magnetic circuit.

As described above, by providing the high-speed shutter mechanism outside the resonator of the laser oscillator, the Q speed can be increased at a high speed.
The first shot of the switch pulse train can be turned off.

Further, by using a high-speed shutter also for continuous wave laser light, the on / off control of the laser light can be performed at high speed, and the takt time, that is, the time required for processing one object can be shortened. It will be possible.

[0031]

As described above, the present invention has an effect that the laser light can be controlled to be turned on and off at high speed by performing the opening operation and the closing operation of the shutter by using the magnetic circuit.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a shutter mechanism according to an embodiment of the present invention.

FIG. 2 is a waveform diagram showing an operation of each unit of FIG.

FIG. 3 is a schematic configuration diagram of a conventional shutter mechanism.

[Description of Reference Signs] 1 shutter plate 2 laser optical axes 5a, 5b, 6a, 6b drive coil 7 open sensor 8 closed sensor 11 fulcrum 31, 32 shutter coil

Claims (2)

[Claims] 1. A shutter mechanism for blocking and unblocking an optical axis of laser oscillation light in a laser oscillator, comprising:
And a shutter that is rotatably supported in a second direction, blocks the optical axis by a rotating operation in the first direction, and releases the blocking of the optical axis by a rotating operation in the second direction. A shutter mechanism comprising: a plate; and a magnetic circuit that rotationally drives the shutter plate in the first and second directions in response to an external command. 2. The magnetic circuit includes a first drive circuit that rotationally drives the shutter plate in the first and second directions in response to the external command, and the shutter in response to the external command. A second plate for rotationally driving the plate in the first and second directions
Drive circuit, angle detection means for detecting the rotation angle of the shutter plate in the blocked and unblocked states of the optical axis, and the drive direction of the second drive circuit according to the detected rotation angle. 2. The shutter mechanism according to claim 1, further comprising a control circuit for controlling so as to be a direction opposite to a driving direction of the first driving circuit.