JPS5837707B2 - Gas Laser Kanno Youchiyakuhouhou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for welding gas laser tubes, and more particularly to a gas laser tube welding method in which a resistance heating element having a bent portion that fits into the laser tube is fixedly arranged in advance on the laser tube. This article relates to a pipe welding method.

Conventionally, when bonding members of glass to each other, for example, a material with good electrical conductivity such as carbon is applied to the surfaces to be joined, and the carbon is instantly burned by applying a high voltage. High-frequency induction can be applied by heating the glass on the joint surface to high temperature, or when joining glass and metal, by interposing a glass brazing material on the surface of the glass joint member to be joined and overlapping the other metal joint member. There is a method of joining by heating a metal joining member with an electric current and melting a glass brazing material.

Furthermore, based on Fig. 1, the drawbacks of each of the above bonding methods, such as bubbles forming on the bonded surface and easy breakage, and the use of a high-frequency induction device as a heating device and the simultaneous heating of the jig, etc., have been eliminated. There is a way to explain it.

That is, a resistance heating element 1 covered with a glass brazing material and having a shape that substantially matches the shape of the surface to be joined is overlapped on the surface to be joined 3 of the joining member 2 and the expected joining surface 5 of the other joining member 4, and This is a method of melting the glass brazing material 7 and bonding the glass by supplying electricity to the resistance heating element 1 through the lead wire 6.

However, in glass bonding using such a resistance heating element 1, when the resistance heating element 1 is superimposed on the joining members 2 and 4, the resistance heating element 1 is held at the end of the joining member by narrowing it with some kind of jig. I have to throw it.

Further, as shown in FIG. 1, the resistance heating element 1 is held by tying the lead wire 6 connected to the resistance heating element 1 to the joining member 2 with a heat-resistant string 8 made of asbestos or the like.
One joining member 2 and the other joining member 4 are glass-joined via a resistance heating element 1.

That is, in the welding of the reflecting mirror to the laser tube, first a resistance heating element is attached to the end face of the laser tube and then covered with a glass brazing material.

Next, a reflecting mirror is placed through the resistance heating element, and a laser beam is applied from the other side of the laser tube.The reflected light of the reflecting mirror is checked and the reflecting mirror surface is adjusted to be perpendicular to the laser tube axis, and melting is performed. Crimp.

In order to hold the resistance heating element in this manner, some kind of jig or heat-resistant string must be used.

Furthermore, when such glass bonding is used to bond a laser tube and a mirror, it is necessary to accurately align the reflecting mirror and the laser tube.

However, positioning the laser tube and the reflecting mirror is actually extremely difficult and time-consuming.

Furthermore, resistance heating elements are prone to deformation due to electrical heating immediately before installing the reflector, so even if some kind of fixing jig is used, the glass brazing material will become uneven and asymmetric, and the adjusted position of the reflector during heating will be After the filler metal has cooled and solidified, it may be misaligned, so do not
Accurate positioning within mrad is not possible.

This invention was made in view of the above drawbacks.
A gas laser tube welding method that allows for accurate and easy positioning of the resistance heating element by accurately holding the resistance heating element with a bent part that fits into the laser tube in advance in the laser tube. is to provide.

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

That is, as shown in FIG. 2, the cross-sectional shape of the laser tube 11 made of borosilicate glass tube is
The position of the resistance heating element 13, which is made of, for example, an iron-nickel-cobalt alloy and has a shape that substantially matches the shape of the surface to be joined, as shown in a perspective view in FIG. 3, is adjusted and fixed.

This resistance heating element 13 has a bent portion 14 integrally formed at the outer peripheral end of an annular base body 13' so as to fit into contact with and be fixed to the outer surface of the laser tube 11.

After fixing this resistance heating element 13 to the laser tube 11, it is immersed in a molten glass brazing material in a dip furnace or the like, so that the surface of the resistance heating element 13 is completely coated and the laser tube 11 and the resistance heating element 13 are bonded together. After the gap is completely filled, it is lifted out.

After welding the laser tube 11 and the resistance heating element 13 in this way, the laser tube 11 and the reflecting mirror 15 are bonded together as shown in FIG.
The resistive heating elements 13 are stacked one on top of the other so as to be narrow, and the resistive heating elements 13 are electrically heated via lead wires 16 connected to the resistive heating elements 13.

Therefore, the glass brazing material 17 coated on the resistance heating element 13 is softened and its viscosity is rapidly reduced.

Then, when the electricity is turned off, the glass brazing material 17 is cooled and solidified, and a good airtight connection between the laser tube 11 and the reflecting mirror 15 is obtained via the resistance heating element 13.

In this way, by attaching the resistance heating element 13 to the laser tube 11 in advance so as to hold it in an accurate position, it is possible to eliminate the trouble of adjusting the position of the laser tube and the reflecting mirror during welding as in the past. At the same time, when the resistance heating element 13 is cooled, the position adjustment of the laser tube and the reflecting mirror will be extremely incorrect due to asymmetry caused by the shift of the glass brazing material. can do.

Furthermore, since the alignment accuracy of the reflecting mirror with respect to the laser tube axis is within lmrad, the success rate in glass brazing can be greatly improved.

In the above explanation, we have explained the case where an L-shaped cross section as shown in the perspective view in Fig. 3 is used as a resistance heating element, but it is also possible to fix it with a resistance heating element having the following shape. can.

Identical parts are denoted by the same reference numerals. FIG. 5 is a partial sectional view showing another embodiment of the resistance heating element, in which the bent part 14 fitted along the inner surface of the laser tube 11 is connected to the annular base 13'. The outer diameter of the resistance heating element 13 is the same as that of the laser tube 1.
By making it the same size as 1, a flat joining surface can be formed.

Furthermore, as shown in the partial sectional view of FIG. 6, by tapering the bent portion 14 in FIG. 5, the fixation to the laser tube can be made more complete.

Furthermore, FIG. 7 is a partial side view of another embodiment, in which all or part of the resistance heating element 13 is formed with a bent portion 14 along both the inner and outer surfaces of the laser tube 11.

Furthermore, in the above explanation, after fixing the resistance heating element to the laser tube, it was explained that the resistance heating element was coated by dipping it into molten glass brazing material, but this resistance heating element was fixed to the laser tube. Bonding may also be performed by using a resistance heating element whose surface has been previously coated with a glass brazing material.

Further, in the above description, the shape of the bonding surface is circular, but it goes without saying that the shape of the bonding surface may be any shape.

As explained above, according to the present invention, a bent portion is formed on the inner or outer peripheral end of the annular base body and is fitted into the laser tube so as to contact the inner or outer surface of the laser tube, and the resistor is covered with a glass brazing material. means for fixedly arranging a heating element so as to face the joining end surface of the laser tube; means for arranging a reflecting mirror so as to face the joining surface of the laser tube via the resistance heating element; and the resistive heating element. Welding of a gas laser tube comprising a means for welding and joining the bonding surface of the laser tube and the reflecting mirror to the resistance heating element by melting the glass brazing material covered on the surface of the resistance heating element by heating the body with electricity. Since this method can be obtained, the resistance heating element can be fixed to the laser tube without using a holding means such as a jig or a string that would hold a conventional resistance heating element.

Furthermore, since it is possible to accurately align the glass brazing filler metal covering the resistance heating element during cooling, even if the resistance heating element is deformed during heating, it will not change when it cools down. It can be fixedly joined at a precise position.

Therefore, it is possible to save the effort of adjusting the position of the laser tube and the laser during welding.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view for explaining a conventional joining method using a resistance heating element, and FIGS. 2 to 4 are partial sectional views and perspective views for explaining an embodiment of the joining method according to the present invention. 5 to 7 are a partial sectional view and a partial side view for explaining other embodiments of the resistance heating element of the joining method according to the present invention. 11... Laser tube, 12... Joint surface of laser tube, 1
3... Resistance heating element, 14... Resistance heating element locking part,
15...Reflector, 16...Lead wire, 17...Glass brazing material.

Claims (1)

[Claims] 1. A resistance heating element is formed on the inner or outer edge of the annular base body to fit into the inner or outer surface of the laser tube, and is covered with a glass brazing material, on the joint end surface of the laser tube. means for fitting together, means for arranging a reflecting mirror so as to face the joint surface of the laser tube via the resistance heating element, and heating the resistance heating element by heating the resistance heating element so that the reflection mirror is covered with the resistance heating element. 1. A method for welding a gas laser tube, comprising means for melting a glass brazing filler metal and welding and joining the joining surfaces of the laser tube and the reflecting mirror to a resistance heating element.