JPH10223948A - Simmer power source circuit for yag laser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the capacity on the high-voltage power source side of a simmer power source circuit and reduce the heat loss on the low-pressure power source side by providing a high-voltage power source section and a low-voltage power source section and making the high-voltage power source section to only output for short times before and after triggering operations. SOLUTION: A high-voltage power source section A and a low-voltage power source section B which outputs a lower voltage than the section A does are respectively connected to both poles of a lamp L through ballast resistances Ra and Rb and a reverse-current preventing diode D is provided between the sections A and B. The section A is controlled by means of a current sensor G, a power supply detecting circuit F, a high-voltage power supply turning-on/off circuit E, etc. When a simmer current flows to the lamp L and the value of the current exceeds a set value, the section A is immediately turned off and only the simmer current from the section B is supplied. Since the section A is only made to operate for a short time when triggering operations are made, the capacity of the section A can be reduced and, since the ballast resistance Rb of the section B can be reduced, the heat loss of the section B can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an improvement in a simmer power supply circuit for a lamp of a YAG laser oscillator.

[0002]

2. Description of the Related Art FIG. 5 shows a power supply circuit of a YAG laser oscillator. Main power circuit and shimmer power circuit are YAG
It is connected in parallel to both poles of the lamp of the laser oscillator, and a trigger circuit is provided on the side of the lamp. In addition, a diode for preventing backflow is provided between the main power supply circuit and the simmer power supply circuit. The lamp of this oscillator is normally discharged in the following order.

A. A high voltage (several kV) is applied between the anode and cathode of the lamp. b. An even higher voltage (several tens of kV) is momentarily applied between the cathode of the lamp and the side of the lamp to bring the lamp into a simmer state (generally referred to as triggering). c. In order to maintain simmer discharge, voltage (several tens to several hundreds of volts) is continuously applied between the anode and the cathode. d. Next, the main power supply circuit required for processing is discharged. e. The simmer discharge in the state c is continued even after the discharge of the main power supply circuit is completed. If the simmer discharge disappears, when the main power supply circuit is to be discharged again, it is necessary to start over from a as described above.

A stabilizing resistor is connected in series to the simmer power supply circuit. When the simmer does not pass through, the simmer power supply voltage is applied to the lamp as it is. , A voltage of several tens to several hundreds of volts is constantly applied. When the simmer is about to disappear, the voltage drop of the stable resistor becomes small, a large voltage is applied to the lamp, the simmer current increases, and a stable discharge is performed.

[0005]

However, since the simmer current is generally several A, the power consumption of the stable resistor may be several kW. Therefore, the size of the simmer power supply circuit is increased, and the heat generated by the stable resistor is taken into consideration. I needed to. The present invention seeks to remedy such disadvantages of the conventional simmer power supply circuit.

[0006]

A conventional YA as described above is used.
In order to improve the disadvantages of the simmer discharge circuit of the lamp for the G laser oscillator, the present invention relates to a simmer power supply circuit for a lamp of a YAG laser oscillator. A power supply section B for outputting a low voltage is provided, and a power supply section A for outputting a high voltage has a function of outputting only a short time before and after the trigger operation.

[0007]

FIG. 1 shows an embodiment of the first aspect of the present invention. As shown, high-voltage power supply A
(About 1500 V) and low-voltage power supply B (100 to 500 V
) Is connected to both poles of the lamp L via stabilizing resistors Ra and Rb, respectively.
A backflow prevention diode D is provided between them. The high-voltage power supply unit A includes a current sensor G, a current detection circuit F, and a high-voltage power supply ON. Controlled by an OFF circuit E and the like, a simmer passes through the lamp L, and when this value exceeds a set value, the high-voltage power supply unit A is immediately turned off. Therefore, when the simmer passes through the lamp L, the simmer current is supplied to the lamp only from the low-voltage power supply unit B thereafter.

FIG. 2 shows the states of the output voltages Va, Vb and the output currents Ia, Ib of the high-voltage power supply section A and the low-voltage power supply section B before and after the trigger operation of this circuit with respect to the time axis.

At time a, a voltage is previously output from the high-voltage power supply unit and the low-voltage power supply unit (the simmer currents Ia and Ib do not flow).
Trigger at b. Simmer currents Ia and Ib begin to flow. At time c (when Ia exceeds the set value), the high-voltage power supply unit A is turned off. The simmer current Ia disappears, and the simmer current Ib is supplied by the low-voltage power supply section B.

As described above, since the high-voltage power supply section A allows a current to flow only for a short time at the time of triggering, the capacity can be reduced, and since the low-voltage power supply section B has a low voltage, the capacity of the stable resistor also decreases. Fever is also reduced.

FIG. 3 shows one embodiment of the second aspect of the present invention. The high voltage power supply unit A is connected via the switch S,
The capacitor C is connected to the lamp via a resistor Ra, and the low-voltage power supply section B is connected to the lamp via a stable resistor Rb and a diode D for preventing backflow. The operation of this circuit is as follows.

A. First, the switch S is closed, and the high-voltage power supply unit A charges the capacitor C with high-voltage charge. b. Trigger after opening switch S. c. When the simmer passes, the capacitor C is discharged, and when the voltage drops to some extent, the simmer current is supplied from the low-voltage power supply unit B. By doing so, the capacity of the high-voltage power supply unit A can be further reduced.

FIG. 4 shows one embodiment of the third aspect of the present invention. The high-voltage power supply A and the low-voltage power supply B are connected in series so that the high-voltage power supply A has a higher voltage than the low-voltage power supply B. The high-voltage power supply unit A has a switch S and a resistor R
a, and the low-voltage power supply section B is connected to the lamp via a stable resistor Rb and a backflow prevention diode D. With this configuration, the capacity of the high-voltage power supply unit A can be further reduced as compared with FIG.

[0014]

As described above, the present invention comprises a high-voltage power supply for outputting a high voltage only when a trigger is performed and a low-voltage power supply for maintaining a simmer discharge only when a simmer passes. In addition, it is possible to reduce the capacity of the high-voltage part, and to reduce the heat loss of the stable resistor of the low-voltage power supply part. can do.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the first aspect of the present invention.

FIG. 2 shows states of a voltage and a current of a high-voltage power supply unit A and a low-voltage power supply unit B before and after operation of the circuit of FIG.

FIG. 3 shows an embodiment of claim 2 of the present invention.

FIG. 4 shows an embodiment of the third aspect of the present invention.

FIG. 5 shows a power supply circuit of a conventional YAG laser oscillator.

[Explanation of symbols]

 A high-voltage power supply B low-voltage power supply C condenser D backflow prevention diode E high-voltage power supply ON. OFF circuit F Current detection circuit G Current sensor L Lamp Ra High voltage power supply stable resistance Rb Low voltage power supply stable resistance T Trigger circuit

Claims (3)

[Claims] 1. A power supply section A for outputting a high voltage, and a power supply section A
And a current sensor, a current detection circuit, and a high voltage power supply ON. So that the power supply A outputs only a short time before and after the trigger operation.
A simmer power supply circuit for a YAG laser, comprising control means including an OFF circuit and the like. 2. A control means for outputting only a short time before and after the triggering operation of the power supply unit A, comprising a circuit comprising a switch, a capacitor, a stable resistor and the like on the output side of the power supply unit A. Item 7. A simmer power supply circuit for the YAG laser according to Item 1. 3. A control means for outputting only a short time before and after the trigger operation of the power supply unit A, the power supply unit A is connected in series to the power supply unit B such that the power supply unit A is on the high voltage side, and the output side of the power supply unit A is controlled. 2. A simmer power supply circuit for a YAG laser according to claim 1, further comprising a circuit comprising a switch, a stable resistor and the like.