JPH0415974A - Laser oscillator - Google Patents

Abstract

PURPOSE:To prevent the ignition error of a laser thereby utterly removing the inferiority in the process of laser processing so as to greatly improve productivity by arranging a discharge start reinforcing ring around the discharge tube between an anode and a cathode, and connecting the discharge start reinforcing ring with the anode or the cathode electrically. CONSTITUTION:Discharge start reinforcing rings 10a and 10b are attached between anodes 2a and 2b and cathodes 3a and 3b, and are connected with the anodes 2a and 2b or the cathodes 3a and 3b, whereby discharge start voltage can be dropped, and especially the ignition error in intermittent output prevented, and discharge start stabilized. Accordingly, even if there is temporal change in the condition of flow velocity, pressure, etc., of the laser medium gas inside the group of discharge tubes composed of one or a plurality of discharge tubes, since discharge start voltage is low, ignition error does not occur, and there never occurs such matters that laser output does not come out or that laser output drops extremely, and the failure in processing ceases to occur.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a laser oscillator that generates laser light for cutting, welding, heat treatment, and the like.

2. Description of the Related Art The structure of a conventional laser oscillator of this type will be explained with reference to FIG. A discharge tube group 1 consisting of one or more discharge tubes includes an anode 2a2b and a cathode 3a, 3 for each discharge tube.
A set of discharge electrodes consisting of B is provided to form two sets of discharge tubes, and the two sets of discharge tubes are arranged symmetrically to form discharge tube group 1.
are formed, and power is supplied to each discharge tube from a high voltage power supply 4. Furthermore, an output mirror 5 and an end mirror 6 are arranged at both ends of the discharge tube group 1 to form an optical resonator. Further, cathode electrodes 3a and 3b at both ends of the discharge tube group 1
A gas circulation path is formed by connecting the anode electrodes 2a and 2b in the vicinity and the central part by an approximately E-shaped circulation tube 7, and this circulation tube 7 includes a blower 8 for circulating gas and a blower 8 for cooling the gas. A heat exchanger 9 is provided.

In a laser oscillator configured in this way, the gas flow direction, the discharge direction, and the laser beam oscillation axis are coaxial, so when viewed from the optical axis direction, the discharge and the gain distribution formed by the discharge are Concentric and symmetrical. Therefore,
Machining performance is said to be good when processing is performed using the output laser light.

Problems to be Solved by the Invention However, since the conditions such as the flow rate and pressure of the laser medium gas within a discharge tube group consisting of one or more discharge tubes change over time, especially when the pulse train has a constant period. In the case of intermittent output, ignition errors occur very rarely, resulting in no laser output or an extremely low laser output, which can lead to processing defects.

Means for Solving the Problems In order to solve the above problems, the present invention arranges a discharge starting auxiliary ring around the outer periphery of the discharge tube between the anode and the cathode, and connects the discharge starting auxiliary ring and the anode or the cathode with electricity. It connects to the

Effect The above configuration reduces the discharge starting voltage and prevents ignition errors even if there are temporal changes in conditions such as the flow rate and pressure of the laser medium gas in the discharge tube group consisting of one or more discharge tubes. There is no problem of no laser output or an extreme drop in laser output, and processing defects are eliminated.

Example An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. Reference numerals 10a and 10b are discharge start assisting rings, which are electrically connected to the anodes 2a and 2b. Components that are the same as those in FIG. 2 are given the same numbers and their explanations will be omitted.

Next, the operation of the oscillator of the above embodiment will be explained using the drawings. Anode 2a is shown in FIGS. 3 and 4.

2b or cathodes 3a, 3b and discharge starting auxiliary rings 10a, 10b connected to anodes 2a, 2b or cathodes 3a,
The relationship between the relative position of 3b and the discharge starting voltage will be shown.

As is clear from FIG. 3, the discharge starting auxiliary ring 10a
, 10b as anode 2a and cathode 3a or anode 2b and cathode 3
When the anode is electrically connected to the outer periphery of the discharge tube between the anodes 2a and 2b, the discharge starting voltage decreases significantly, and gradually decreases from around 30% of the distance between the anodes 2a and 2b and the cathodes 3a and 3b. The anodes 2a, 2b and the cathode 3a,
It becomes almost constant near half of the distance between 3b.

Note that the "relative position of the discharge start assisting ring" in FIG. 3 is the position indicated by . Further, as is clear from FIG. 4, when the discharge starting auxiliary ring 10 is attached to the outer periphery of the discharge tube between the anode 2a and the cathode 3a or between the anode 2b and the cathode 3b, it is electrically connected to the cathodes 3a and 3b. The discharge starting voltage decreases significantly, and shows a tendency to become gradual from around 30% of the distance between the anode 2a2b and the cathodes 3a, 3b,
It becomes almost constant near half the distance between the anode 2a2b and the cathodes 3a, 3b.

In addition, the "relative position of the discharge start assisting ring" in FIG. 4 is the position represented by.

In Figure 3, the relative position of the discharge starting auxiliary ring is 0.
%, the above ring is the anode 2a.

In Fig. 4, when the relative position of the discharge starting auxiliary ring is 0%, it means that the ring overlaps with the cathodes 3a and 3b, and in either case, the discharge starts. This is equivalent to not having the starting auxiliary ring attached at all, and this shows that without the starting auxiliary ring, the discharge starting voltage would be extremely high, increasing the possibility of mis-ignition. Therefore, the discharge starting auxiliary rings 10a, 10b are attached between the anodes 2a, 2b and the cathodes 3a, 3b at the anodes 2a, 2b or the cathodes 3a.

By electrically connecting with 3b, the discharge starting voltage can be lowered, ignition errors can be prevented especially during intermittent output, and the discharge starting can be stabilized. Therefore, even if there are temporal changes in conditions such as the flow rate and pressure of the laser medium gas in a discharge tube group consisting of one or more discharge tubes, ignition errors will not occur because the discharge starting voltage is low. , there is no possibility that the laser output will not be output or the laser output will be extremely reduced, and there will be no processing defects.

Effects of the Invention As is clear from the above explanation, according to the present invention, it is possible to prevent laser ignition mistakes and eliminate defects in the laser processing process, and it is possible to dramatically improve productivity. .

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the laser oscillator of the present invention, Fig. 2 is a block diagram showing a conventional laser oscillator, and Fig. 3 is the relationship between the position of the discharge start auxiliary ring and the discharge start voltage (discharge start Figure 4 is a graph showing the relationship between the position of the discharge starting auxiliary ring and the discharge starting voltage (when the auxiliary discharge ring is electrically connected to the cathode). It is. 1...Discharge tube group, 2a...Left anode, 2
b...Right anode, 3a...Left cathode, 3b
...Right cathode, 4...High voltage power supply, 5...
...Output mirror 6...Terminal mirror 7...
...Circulation tube, 8...Blower, 9...
...Heat exchanger, 10a...Left discharge start auxiliary ring, 10b...Right discharge start auxiliary ring. Name of agent: Patent attorney Shigetaka Awano Haka 1 Meizoku Denkan Shoyu wo E Ishi Hatoya k I7st book shows stone high ground tile electric t Mira 1 abbreviation Mirai Ai Te J-1 Ritsu 4 I (To ζ @2Figure 1θ^ and ▼'-t Fw”j is supplemented with “Kari~ri lθ”
b Shirakami Mekarigori /' / The main aim of the 14" series
j1(n2 fig.

Claims (2)

[Claims] (1) A discharge tube group consisting of one or more discharge tubes having at least one pair of discharge electrodes consisting of an anode and a cathode, a mirror for laser resonance disposed at both ends of this discharge tube group, and a It consists of a circulation pipe body that is connected to the discharge tube group in the vicinity and forms a gas circulation path together with the discharge tube group, and a blower device that circulates gas as a laser medium in the gas circulation path, and is connected to the anode and cathode. A laser oscillator characterized in that a discharge starting auxiliary ring is disposed around the outer periphery of a discharge tube located between the discharge tubes, and the discharge starting auxiliary ring is electrically connected to an anode or a cathode. (2) The laser oscillator according to claim (1), wherein the distance between the discharge starting auxiliary ring and the electrode to which the ring is electrically connected is greater than 30% of the distance between the anode and cathode.