JPH0832154A - Laser rod holder mounting structure - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Laser rod holder mounting that can cool the entire rod holder efficiently when inserting the rod holder of the solid-state laser device through the opening so as to project from the casing. Provide structure. A rod holder 19 for supporting a laser rod 15 arranged in a cooling water filling space 14 inside a casing 11 of a solid-state laser device is inserted into an opening of a casing, and a centering portion 27 of the rod holder allows the opening of the opening. Mount so that it matches the central axis. The centering portion 27 is formed with an outer diameter larger than the outer diameter of the end portion on the laser rod supporting side,
Further, a plurality of arcuate outer peripheral surface portions 27 that are partially provided in the circumferential direction to directly or indirectly contact the inner peripheral surface of the opening portion and between them are formed, and the central axis of the rod holder is larger than the radius of the arcuate outer peripheral surface portions. The outer peripheral surface portion 27 is formed at a position where the radial distance from the outer peripheral surface is short, and the gap portion 29 that appears between each outer peripheral surface portion and the inner peripheral surface of the opening serves as a cooling water passage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for mounting a laser rod holder, and more particularly, to a laser oscillator casing constituting a solid state laser device, in which a rod holder for supporting a laser rod which is a laser medium is mounted in a casing of the laser oscillator. It relates to a structure that is inserted and attached.

[0002]

2. Description of the Related Art As is well known, some solid-state laser devices are provided with a laser oscillator main body, and the laser oscillator main body is composed of a box-shaped casing and a lid for closing the upper opening. In such a laser oscillator main body, a reflector is generally arranged in its casing. An Nd: YAG laser rod, for example, is arranged as a laser medium in a space formed in the axial direction of the reflecting cylinder, and an excitation lamp as an excitation source is installed in this space.

In such a laser oscillator body, N
The d: YAG laser rod is irradiated with an excitation lamp and energy is injected. At this time, in order to allow the rod to efficiently absorb the energy of the excitation lamp, the inner peripheral surface of the space is mirror-finished as a reflecting mirror for converging the rod and the lamp. From that meaning, the member that defines the space is defined as a reflecting cylinder.

This space is filled with cooling water for cooling the laser rod, the excitation lamp, and the light collecting and reflecting surface which is the inner peripheral surface. Further, a cooling water passage is formed in the reflecting cylinder, the cooling water passage communicates with a cooling water inflow pipe and a cooling water outflow pipe provided in the casing, and the cooling water is flowed into the cooling water passage in the reflecting cylinder at any time. The temperature rise of the reflector is prevented.

The laser rod, which is placed in the cooling water in the reflecting cylinder of the laser oscillator body, is supported at both ends by being inserted into one end of a cylindrical rod holder and being watertightly sealed. The other end of the rod holder that supports the laser rod at one end is inserted into an opening formed in the casing of the laser oscillator body and attached so as to project to the outside.

The rod holder which is inserted through the opening of the casing is fixed to the casing with a highly accurate position holding structure so as not to cause an axial deviation, that is, a disagreement between the center axis of the opening and that of the rod holder. It That is, in the rod holder mounting structure at the casing opening, the rod holder is formed such that the outer diameter of the rod holder in the axial direction is larger than that of the other portion, and the outer diameter of the middle portion is formed to be substantially the same as the inner diameter of the opening of the casing. As a result, when the rod holder is inserted into the opening, the maximum outer diameter portion is fitted and mounted so as to accurately slide on the inner peripheral surface of the opening.

On the other hand, in the opening of the casing, a small screw hole for attaching a set screw is formed extending in the radial direction at a portion where the maximum outer diameter portion of the rod holder is located. A set screw is screwed into the screw hole, and the tip end of the set screw is brought into contact with the peripheral surface of the maximum outer diameter portion of the rod holder to prevent axial movement of the rod holder.

Of course, the opening formed in the casing of the laser oscillator body through which the rod holder is inserted is provided with a strict seal so that the cooling water filled in the space inside the reflecting cylinder does not leak out of the casing. .

[0009]

However, the conventional structure for mounting the rod holder by inserting it into the opening of the casing has the following problems. That is, as described above, when the rod holder is inserted through the opening formed in the casing of the laser oscillator body and attached, a large outer diameter formed in the axially substantially intermediate portion of the rod holder to prevent the occurrence of axis deviation. The portion is adapted to be accurately slidably fitted to the inner peripheral surface of the opening portion.

Therefore, the cooling water filled in the internal space of the reflecting cylinder is blocked by the large outer diameter portion of the rod holder even if it enters the opening, so that it cannot enter further. Therefore, the rod holder was hardly subjected to the cooling action in the outer portion including the large outer diameter portion. As a result, there is a problem that the temperature rises in many parts of the rod holder, and as a result, the generation of laser light is adversely affected.

An object of the present invention is to solve the above conventional problems, and a rod holder for supporting a laser rod in a laser oscillator body of a solid-state laser device is projected outside from a casing of the laser oscillator body. Accordingly, it is an object of the present invention to provide a laser rod holder mounting structure capable of efficiently cooling the entire rod holder when it is mounted by inserting it through the opening.

[0012]

According to the present invention, a laser rod 15 is arranged in a cooling water filling space 14 inside a casing 11 of a laser oscillator body 10 which constitutes a solid-state laser device.
The rod holder 19 supporting the rod holder 19 is inserted into the opening 26 formed in the casing 11,
Is a structure in which the center axis of the is aligned with that of the opening 26 by the centering portion 27 formed in a part of the axial direction, and is attached, and is configured as follows in order to solve the above-mentioned technical problem. There is.

That is, in the laser rod holder mounting structure of the present invention, the centering portion 2 of the rod holder 19 is used.
A plurality of 7 are formed with an outer diameter that is at least larger than the outer diameter of the end portion of the laser rod supporting side, and are partially provided in the circumferential direction that directly or indirectly contact the inner circumferential surface of the opening 26. Of the first outer peripheral surface portion 27a of the
A second outer peripheral surface portion 27b which is formed between the outer peripheral surface portions 27a of the first outer peripheral surface portion 27a and is formed at a position where the radial distance from the central axis of the rod holder 19 is shorter than the radius of the first outer peripheral surface portion 27a, A space 29 that appears between the second outer peripheral surface portion 27b and the inner peripheral surface of the opening portion 26 of the casing 11 is used as a cooling water passage along the rod holder 19 (claim). 1). The constituent features of the laser rod holder mounting structure according to the present invention will be individually described below.

(Centering part of rod holder) The centering part 27 of the rod holder 19 has the opening 26 as described above.
Of the plurality of first outer peripheral surface portions 27a and the plurality of second outer peripheral surface portions 27b formed between the plurality of first outer peripheral surface portions 27a. , The second outer peripheral surface portion 27b is the centering portion 27
When viewed in cross section, the first outer peripheral surface portion 27a is composed of six outer peripheral surfaces formed at equal intervals of 60 degrees in the circumferential direction.
Can also be composed of six outer peripheral surfaces that are equally spaced in the circumferential direction.

Of course, these first and second outer peripheral surface portions 27
The numbers of a and 27b may be arbitrary. But in that case, the first
If the number of outer peripheral surface portions 27a is large, the contact area becomes large and the stability of the rod holder attachment is improved, but the cross-sectional area of the flow passage defined by the second outer peripheral surface portion 27b becomes small, and air (air bubbles) are generated. Since it is difficult for the cooling water to escape and therefore the cooling water will not flow easily, it is preferable to design in consideration of these balances.

(Passage for Cooling Water) With the formation of the second outer peripheral surface portion 27b of the rod holder 19, a space 29 is formed between the second outer peripheral surface portion 27b and the inner peripheral surface portion of the opening 26 along the axial direction. Appears. The space 29 is a cooling water passage.

<Additional Requirement in the Present Invention> The laser rod holder mounting structure of the present invention comprises the above-mentioned essential components. However, when the following components are further added, or the essential components are specifically described. It holds even in the following cases.

That is, in the laser rod holder mounting structure of the present invention, the second outer peripheral surface portion 27b is formed as a flat surface (corresponding to claim 2). Furthermore, in the laser rod holder mounting structure of the present invention,
The opening 26 is formed integrally with the wall of the casing 11 and is formed in a rod holder mounting portion 30 that protrudes inside the casing. The rod holder mounting portion 30 has a diameter that extends toward the opening 26. Is provided with a set screw 32 that is screwed into a screw hole 31 provided in the direction, and has its tip end abutted and fixed to the outer peripheral surface of the centering portion 27 of the rod holder 19 through which the opening 26 is inserted. The rod holder 19 and the opening 26 are located outward of the casing with respect to the fixing position by the screw 32.
This is a case where an O-ring 25 is attached to the outer periphery of the rod holder 19 to perform a water-tight seal with (corresponding to claim 3).

Further, in the laser rod holder mounting structure of the present invention, the rod holder mounting portion 30 is provided with a water passage hole 33 for communicating cooling water which communicates with the opening 26 (corresponding to claim 4). ).

[0020]

According to the laser rod holder mounting structure of the present invention, the rod holder is inserted into the opening portion 26 formed in the casing 11 of the laser oscillator body 10, and the centering portion 27 is positioned in the opening portion 26. . This time,
A plurality of first outer peripheral surface portions 2 forming the centering portion 27
Since 7a directly or indirectly contacts the inner peripheral surface of the opening 26, the rod holder 19 is held at an accurate position with respect to the opening 26 without deviation of the central axis line.

Moreover, the plurality of first outer peripheral surface portions 27a which directly prevent these axial deviations are formed at intervals in the circumferential direction, and in the meantime, in cooperation with the inner peripheral surface of the opening 26, the intervals are formed. Since the second outer peripheral surface portion 27b that forms the portion 29 is formed, the gap portion 29 serves as a cooling water passage and the cooling water filled in the casing is provided along the rod holder 19 near the outlet of the opening portion 26. Enter up to the seal part. As a result, most of the entire circumference and the entire length of the rod holder 19 is subjected to the cooling action by the cooling water, the temperature rise is suppressed, and the preferable environment for generating the laser light is achieved.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The laser rod holder mounting structure of the present invention will now be described in more detail with reference to the embodiments shown in the drawings.
FIG. 1 shows a laser oscillator body 10 in a solid-state laser device.
It is shown. The overall structure of the laser oscillator main body 10 is almost the same as the conventional one, and is composed of a box-shaped casing 11 and a lid 12 that closes the upper opening.

A reflecting cylinder 13 is arranged in the casing 11. In the space 14 formed in the axial direction of the reflecting cylinder 13, for example, N as a laser medium is used.
A d: YAG laser rod 15 is arranged, and an excitation lamp 16 as an excitation source is installed in this space 14. The inner peripheral surface of the space 14 is mirror-finished as a converging reflecting mirror that surrounds the rod 15 and the lamp 16 so that the energy of the excitation lamp 16 is efficiently absorbed by the rod 15.

The space 14 is filled with cooling water for cooling the laser rod 15, the excitation lamp 16 and the light collecting and reflecting surface which is the inner peripheral surface. Further, a cooling water passage is formed in the reflection tube 13, and the cooling water passage is provided in the casing 11 and the cooling water inflow pipe 17 and the cooling water outflow pipe 1 are provided.
The cooling water is flowed through the cooling water passage in the reflecting cylinder 13 at any time to prevent the temperature of the reflecting cylinder 13 from rising.

In this way, the laser rod 15 arranged in the cooling water in the reflecting cylinder 13 of the laser oscillator body 10 is arranged.
Both ends thereof are inserted into a cylindrical rod holder 19 and supported while being watertightly sealed. Here, the support structure of the laser rod 15 in the watertightly sealed state by the rod holder 19 will be briefly described. The cylindrical rod holder 19 has an inlet at the end portion on the laser rod mounting side as shown in FIGS. 2 and 3. A screw portion 20 formed on the inner peripheral surface of the portion 19a and a radially inwardly bulging portion 21 formed at a predetermined axial position from the inlet portion 19a are provided.

Usually, the rod holder 19 is made of a metal material such as stainless steel. However, it goes without saying that the solid-state laser device may be made of other materials as long as it is preferable.

The end of the laser rod 15 is inserted into the rod holder 19 through the inlet 19a. At that time, the laser rod 15 inserted into the rod holder 19
Backup ring 2 which is a seal member on the outer circumference of the end of
Two and two O-rings 23 are attached and inserted into the rod holder 19 together with the laser rod end.
A plug 24 having a threaded portion formed on the outer circumference is attached to the inlet portion 19a of the rod holder 19 by being screwed into the threaded portion 20 on the inner peripheral surface of the inlet portion. Backup rings 22 and 2
The two O-rings 23 are pressed inward in the axial direction by the pressure of the plug 24 entering the rod holder, whereby the backup ring 23 and the two O-rings 23 and the bulging portion 21 in the rod holder 19 are formed. It is compressed by being sandwiched by the plug 24.

When the backup ring 22 and the two O-rings 23 are compressed, they closely adhere to the laser rod 15, and the laser rod 15 is also stably supported by these sealing members. The backup ring 23 is preferably made of Teflon resin, but may be made of another elastic member or the like.

When the laser rod 15 having such a structure is attached to the rod holder 19 in a watertight sealed state in the space 14 inside the reflection cylinder 13 of the laser oscillator body 10, the cooling water in the space 14 of the reflection cylinder 13 is The rod holder 19 tries to enter the inside from the inlet portion 19a.

However, since the two O-rings 23 are located axially inward of the inlet portion 19a, O
When the installation position of the ring 23 is viewed, the entry path of the cooling water is only in the axial direction along the laser rod 15.
As a result, the entry of cooling water from this direction is usually O-
The direction is as designed for the ring 23, and therefore the originally designed sealing performance can be exhibited.

In order to prevent leakage of the cooling water by making a watertight seal in the portion where the rod holder 19 penetrates the casing 11 of the laser oscillator body 10 to the outside,
An O-ring 25 is attached to the outer circumference of the rod holder 19,
Thereby, the outer peripheral portion of the rod holder 19 and the casing 11
The inner peripheral surface of the opening is sealed.

By the way, in the two rod holders 19 which support the respective ends of the laser rod 15 while sealing in a watertight manner, the rod holders 19 are formed in the casing 11 of the laser oscillator body 10. Opening 26
A centering portion 27 is formed in the axially substantially middle portion of the rod holder 19 so that the center axis of the opening 26 and the rod holder 19 are exactly aligned with each other when the rod holder 19 is inserted into the rod holder 19.

The centering portion 27 is formed by the laser rod 15
A plurality of arc-shaped first outer peripheral surface portions 27a that are formed with an outer diameter larger than the outer diameter of the end portion side that supports the arc, and are partially provided in the circumferential direction, and the plurality of first outer peripheral surface portions 27a.
4 and is formed at a position where the radial distance s from the central axis of the rod holder 19 is shorter than the radius r of the first outer peripheral surface portion 27a, that is, the position r> s, as shown in FIG. And a second outer peripheral surface portion 27b.

An outer tube 28 is fitted around the centering portion 27 of the rod holder 19.
This outer tube 28 has a split groove 28a formed in the axial direction, and when mounted on the centering portion 27, its inner peripheral surface has a centering portion 2a.
It adheres to the first outer peripheral surface portion 27a of No. 7. This outer tube 28
Is for preventing the casing 11 made of acrylic resin from being damaged when the rod holder 19 moves in the axial direction, and functions as a so-called protective tube.

When the outer tube 28 is mounted on the centering portion 27 of the rod holder 19, the outer diameter thereof is substantially equal to the inner diameter of the opening 26 for inserting the rod holder formed in the casing 11. Is formed.

When the rod holder 19 with the outer tube 28 attached to the centering portion 27 is inserted into the opening 26 of the casing 11 as described above, the outer tube 28 is fitted into the opening 26 in a close contact state. As a result, the central axis of the opening 26 and that of the rod holder 19 can be kept in perfect alignment.

In this way, the opening 2 of the casing 11
When the rod holder 19 is inserted in 6, the cooling water in the casing 11 enters from the inlet of the opening 26. Then, the plurality of first outer peripheral surface portions 27 contacting the inner peripheral surface of the outer tube 28 in order to directly prevent the axis deviation in the centering portion 27.
Since the second outer peripheral surface portion 27b formed between a and the interval portion 29 is formed apart from the inner peripheral surface of the outer tube 28, the interval portion 29 serves as a cooling water passage.

As a result, the cooling water that has entered from the inlet side of the opening 26 enters along the rod holder 19 to the seal portion (attachment portion of the O-ring 25) near the outlet of the opening. As a result, most of the entire circumference and the entire length of the rod holder 19 is subjected to the cooling action by the cooling water, the temperature rise is suppressed, and the preferable environment for generating the laser light is achieved.

The opening 26 through which one of the two rod holders 19 supporting both ends of the laser rod 15 is inserted,
As shown in FIG. 1, it is formed on a rod holder mounting portion 30 that is integrally provided so as to project from the inner end surface of the casing 11 of the laser oscillator body 10. A screw hole 31 is formed on the upper surface of the rod holder mounting portion 30, and the screw hole 31 reaches the opening 26.

A set screw 32 is screwed into the screw hole 31, and the tip end of the set screw 32 is a split groove of the outer tube 28 for preventing axial movement of the rod holder 19 inserted into the opening 26 as described above. 28a directly contacts the first outer peripheral surface portion 27a of the centering portion 27. Then, on the side surface of the rod holder mounting portion 30, as described above, water passage holes 33 are formed for returning the cooling water that has entered the opening 26 from the inlet side to the inside of the casing 11 and for removing air (air bubbles). ing. When the temperature of the contact point of the screw 32 was measured on the outer surface of the holder in this example, the laser output was 800 W and the maximum temperature was 37 ° C. It should be noted that the maximum temperature was 60 ° C. in the comparative example under the same conditions except that a cylindrical holder was used for this example.

In the above-described embodiment, the tip of the set screw 32 is located at the first position in the centering portion 27 of the rod holder 19.
Although it is configured to be brought into contact with the outer peripheral surface portion 27a of the above, it may be brought into contact with the second outer peripheral surface portion. However, in that case, one cooling water passage 29 is partially blocked, which causes a slight decrease in the cooling water flow rate.

Further, although the first outer peripheral surface portion 27a is an arcuate outer peripheral surface formed with a radius substantially the same as the inner diameter of the outer tube 28 in the above-mentioned embodiment, it is not limited to the arcuate outer peripheral surface. It may be a corner. In that case, the outer peripheral surface of the centering portion 27 has a polygonal shape when viewed in cross section. Also,
The purpose of forming the second outer peripheral surface portion 27b is to form the space portion 29 between the inner peripheral surface of the outer tubular pipe 28 and use this as a cooling water passage, so that the second outer peripheral surface portion is It is needless to say that the shape is not limited to the flat surface as in the above-described embodiment, and that it can be formed in various shapes such as a concave shape.

[0043]

As described above, according to the laser rod holder mounting structure of the present invention, the rod holder supporting the laser rod is inserted into the opening formed in the casing of the laser oscillator body, and its centering portion is inserted. Since the plurality of first outer peripheral surface portions constituting the centering portion directly or indirectly contact the inner peripheral surface of the opening portion when the rod holder is positioned in the opening portion, the rod holder is attached to the opening portion. The central axis will be held in the correct position without shifting.

In addition, the second outer peripheral surface portion between the plurality of first outer peripheral surface portions which are aligned with each other in the rod holder cooperates with the inner peripheral surface of the opening to form a space portion, and the space portion is formed. Serves as a cooling water passage and the cooling water filled in the casing enters along the rod holder up to the seal near the outlet of the opening. By receiving the cooling action, the temperature rise is suppressed, and a preferable environment for generating the laser light can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a laser oscillator body of a solid-state laser device to which a laser rod holder mounting structure of the present invention is applied.

2 is an exploded perspective view of a structure in which a laser rod is attached to a rod holder in a sealed state in the laser oscillator body shown in FIG.

FIG. 3 is a sectional view showing a laser rod holder mounting structure according to an embodiment of the present invention.

4 is a perspective view of the rod holder attached through the opening of the casing of the casing of FIG.
FIG. 4 is a cross-sectional view taken along line -4.

[Explanation of symbols]

 10 Laser Oscillator Main Body 11 Casing 12 Lid 13 Reflecting Tube 14 Space 15 Laser Rod 16 Excitation Lamp 17 Cooling Water Inflow Pipe 18 Cooling Water Outflow Pipe 19 Rod Holder 19a Inlet 20 Screw Part 21 Bulging Part 22 Backup Ring 23 O-Ring 24 Plug 25 O-ring 26 Opening portion 27 Centering portion 27a Arc-shaped outer peripheral surface portion 27b Outer peripheral surface portion 28 Outer cylinder tube 28a Split groove 29 Cooling water passage (interval portion) 30 Rod holder mounting portion 31 Screw hole 32 Set screw 33 Water passage hole

Claims (4)

[Claims] 1. A rod holder for supporting a laser rod arranged in a cooling water filling space inside a casing of a laser oscillator body constituting a solid-state laser device is inserted into an opening formed in the casing, and the rod holder. In the structure in which the center axis of the rod holder is attached by aligning it with the centering portion formed in a part of the axial direction of the opening portion, the centering portion of the rod holder is at least outside the laser rod supporting side end portion. A plurality of first outer peripheral surface portions that are formed with an outer diameter larger than the diameter and that are partially provided in the circumferential direction that directly or indirectly contact the inner peripheral surface of the opening, and a plurality of these first outer peripheral surface portions. A second outer peripheral surface portion which is formed between the outer peripheral surface portions and is formed at a position where a radial distance from the central axis of the rod holder is shorter than a radius of the first outer peripheral surface portion, Laser rod holder mounting structure, characterized in that the spacing unit to emerge and cooled water path along the rod holder between the opening peripheral surface of the second outer peripheral surface the casing. 2. The laser rod holder mounting structure according to claim 2, wherein the second outer peripheral surface portion is formed as a flat surface. 3. The opening is formed in a rod holder attachment portion that is integrally provided in a wall portion of the casing and protrudes inside the casing, and the rod holder attachment portion has a diameter that increases toward the opening. A fixing screw that is screwed into a screw hole provided in the direction, and has its tip end abutting and fixing to the outer peripheral surface of the rod holder that is inserted through the opening, and further the casing is more fixed than the fixing position by the fixing screw. 3. The laser rod holder according to claim 1, wherein an O-ring is attached to the outer periphery of the rod holder so as to perform a watertight seal between the rod holder and the opening in the outward direction. Mounting structure. 4. The laser rod holder mounting structure according to claim 3, wherein the rod holder mounting portion is formed with a cooling water circulation hole communicating with the opening.