JPH0832145A - Laser rod support structure - Google Patents

Abstract

(57) [Abstract] [Purpose] Improving the performance of water-tight seal at the support part of the laser rod by the rod holder in the laser oscillator body of the solid-state laser device, and thus the reliability of the laser oscillator body for long-term use To provide a laser rod support structure capable of improving In a solid-state laser device, a laser rod is supported by a rod holder in a watertight sealed state, and has a tubular shape in which a radially inward bulging portion 21 is formed at a predetermined axial position from an inlet portion 19a. The ring-shaped members 22 and 23 are attached to the outer periphery of the end of the laser rod 15 whose end is inserted from the entrance of the rod holder 19, and the plug 24 loosely fitted to the end of the laser rod 15 is attached to the rod holder 19.
The ring-shaped member is fitted into the inlet portion 19a of the plug and is pressed against the bulging portion 21 by the fitting pressure of the plug 24 to be compressed, and the ring-shaped member is brought into close contact with the laser rod 15 to seal and hold it. And

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser rod supporting structure, and more specifically, in a solid-state laser device, a laser rod, which is a laser medium, is supported in a laser oscillator main body while a watertight seal is secured by a rod holder. Regarding the structure.

[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.

As described above, the laser rod arranged in the cooling water in the reflecting cylinder of the laser oscillator body is inserted into both ends of the cylindrical rod holder and supported while being watertightly sealed. Conventionally, mounting of a laser rod in a watertight sealed state on a cylindrical rod holder has been performed with reference to FIG.
It was done as shown in. That is, the conventional rod holder 1 is formed with the cap mounting portion 2 having a small outer diameter at the end portion on the laser rod mounting side.
A screw portion 3 is formed on the outer peripheral surface of the.

When attaching the laser rod 4 to the rod holder 1, the end portion of the laser rod 4 is inserted from the opening of the end surface of the cap mounting portion 2 of the rod holder 1. At that time, the O-ring 5 is fitted on the outer periphery of the end portion of the laser rod 4. Thereafter, a cap 7 having substantially the same outer diameter as that of the holder 1 previously mounted on the laser rod 4 is screwed onto the outer peripheral threaded portion 2 of the cap mounting portion 2 of the rod holder 1 with the inner peripheral threaded portion of the cap 7. It can be tightened.

This cap 7 is provided with a flange portion 7a protruding inward in the radial direction at one end thereof.
When is screwed into the cap mounting portion 2 of the rod holder 1 and tightened, the O-ring 5 is sandwiched between the end surface of the rod holder 1 and the flange portion 7a of the cap 7 and compressed. As a result, the O-ring 5 is pressed against the end surface of the rod holder 1 and the outer peripheral surface of the laser rod 4, seals the cooling water from entering the rod holder 1, and supports the laser rod 4.

[0008]

However, the conventional structure for mounting and sealing the laser rod on the rod holder has the following problems. That is, as described above, when the flanged cap 7 is mounted on the cap mounting portion 2 of the rod holder 1 and tightened, the stepped vertical surface of the cap mounting portion 2 and the end surface of the cap 7 formed with a small outer diameter are completely removed. Further, it is very difficult to bring them into close contact with each other with a predetermined pressure because of a problem of processing accuracy and a problem that the O-ring 5 fitted on the outer circumference of the laser rod 4 has to be in a predetermined compressed state.

However, when a gap 8 is formed between the step vertical surface of the cap mounting portion 2 and the end surface of the cap 7, cooling water is attached from the gap 9 to the cap of the rod holder 1 as indicated by an arrow 9 in FIG. Part 2 It penetrates to the outer peripheral side of the installation part of the O-ring 5 along the outer peripheral thread part 3, and when there is a slight contact failure part between these rings or other components, it immediately enters the rod holder 1. Was thought to do.

Therefore, in such a conventional structure, it is said that there is a problem in the durability of the watertight seal at the mounting portion of the laser rod to the rod holder, and the reliability of the laser oscillator main body for long-term use is low. There was a problem to say.

Further, a part of the laser light emitted from the laser rod is reflected and returns. There is a problem that this laser return light hits the O-ring and deteriorates it.

An object of the present invention is to solve the above-mentioned conventional problems, and to improve the performance of a watertight seal at the mounting portion of the laser rod by the rod holder in the laser oscillator body of the solid-state laser device. Another object of the present invention is to provide a laser rod support structure capable of preventing deterioration of a seal portion due to irradiation of laser return light and thereby improving reliability of the laser oscillator main body for long-term use.

[0013]

The present invention is a structure for supporting a laser rod on a rod holder in a watertight sealed state in a solid-state laser device, and is configured as follows in order to solve the above-mentioned technical problem. ing.

That is, in the laser rod support structure of the present invention, the cylindrical rod holder 19 is formed with the radially inwardly bulging portion 21 formed at the axially predetermined position from the inlet portion 19a of the end portion.
And a laser rod 15 whose end is inserted from the entrance 19a of the rod holder 19, and an outer circumference of the end of the laser rod 15 inserted from the entrance 19a of the rod holder 19. Ring-shaped member 2
2, 23 and the inlet portion 19a of the rod holder 19
A plug 24 that is fitted inside, and the ring-shaped members 22 and 23 are pressed against the bulging portion 21 and compressed by the fitting pressure of the plug 24 into the inlet portion 19a of the rod holder 19; Ring-shaped members 22, 23
Is closely attached to the laser rod 15 for sealing (corresponding to claim 1). The constituent features of the laser rod support structure according to the present invention will be individually described below.

(Rod Holder) The rod holder 19 which supports the laser rod 15 has a cylindrical shape and allows passage of laser light. The rod holder 19 has a radially inwardly bulging portion 21 formed at a predetermined axial position from the inlet portion 19a. The rod holder 19 is preferably made of a metal material such as stainless steel.

(Laser Rod) The laser rod 15 is attached by inserting the end thereof into the inside from the end inlet 19a of the rod holder 19. The laser rod 15 itself is exactly the same as the conventional one, and examples thereof include an Nd: YAG laser rod, a ruby laser rod, and a glass laser rod. This laser rod absorbs the energy of the excitation lamp 16 to generate laser light.

(Ring-shaped member) Ring-shaped members 22 and 23 are attached to the outer periphery of the end portion of the laser rod 15 inserted from the inlet portion 19a of the rod holder 19. The members 22 and 23 are pressed against the rod holder 19 from the outside in the axial direction, and come into contact with the bulging portion 21 and the sealing surface 26 of the rod holder 19 and are compressed, whereby the ring-shaped member 23 is sealed. The close contact with the surface 26 and the outer peripheral surface of the laser rod 15 are ensured, and the sealing property is improved.

(Plug) Inlet 19 of rod holder 19
A plug 24 is attached to a, and the ring-shaped member 2 is caused by the pressure of fitting the plug 24 into the rod holder 19.
2 and 23 are the bulging portions 21 on the inner surface of the rod holder 19 described above.
It is sandwiched between and compressed.

<Additional Requirement in the Present Invention> The laser rod support structure of the present invention comprises the above-mentioned essential constituent elements, but the constituent elements are also established in the following specific cases. The additional components include ring-shaped sealing members 22 and 23 composed of a backup ring 22 and at least one O-ring 23, and the backup ring 22 is brought into contact with the bulging portion 21 of the rod holder 19. (Corresponding to claim 2). It is desirable that the O-ring is made of silicone rubber and has a small absorption of laser light.

The plug 24 may be a ring-shaped member having a threaded portion formed on the outer periphery thereof. In this case, it is necessary to form the screw portion 20 on the inner peripheral surface of the inlet portion 19a of the rod holder 19. When such a ring-shaped plug 24 is fitted into the inlet portion 19a of the rod holder 19, the end portion of the laser rod 15 is loosely fitted in advance before being inserted into the rod holder 19, and after the insertion of the laser rod, The plug 24 is screwed and attached to the entrance of the rod holder 19 (corresponding to claim 3). The backup ring 22 is preferably made of Teflon resin (corresponding to claim 4). In the case of Teflon, the width is 1
If the thickness is equal to or greater than mm, the light transmittance is small and substantially constant, so that it may be equal to or greater than 1 mm in order to shield the laser return light to the 0-ring.

Further, as another additional component, the seal portion between the laser rod and the rod holder is located in the cooling water filling chamber 14 in the laser oscillator body 10, and the cooling water flows from the seal portion into the rod holder. It can be used to prevent entry (corresponding to claim 5).

[0022]

According to the laser rod support structure of the present invention, when the laser rod 15 is attached to the rod holder 19 in the space 14 inside the reflecting cylinder 13 of the laser oscillator body 20 in a watertight sealed state, the space 14 of the reflecting cylinder 13 is provided. The cooling water inside tries to enter the inside from the inlet portion 19a of the rod holder 19. However, since the ring-shaped seal member 23 is located axially inward of the inlet portion 19a, the entrance path of the cooling water when the installation position of the ring-shaped seal member 23 is viewed is the laser rod 15. Only along the axial direction. As a result, the inflow of cooling water from this direction is normally in the direction as designed for the seal member 23, and therefore the originally designed sealing performance can be exhibited.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The laser rod support 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. 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 main body 10
Both ends thereof are inserted into a cylindrical rod holder 19 and supported while being watertightly sealed. Therefore, in the laser rod support structure according to the present embodiment, as shown in FIG. 2, the cylindrical rod holder 19 has the screw portion 20 formed on the inner peripheral surface of the inlet portion 19a at the end portion on the laser rod mounting side, and the screw portion 20. It is provided with a radially inwardly bulging portion 21 formed at a predetermined position in the axial direction from the inlet portion 19a.

Usually, the rod holder 19 is made of a metallic 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 from 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 strongly 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.

With the support structure having such a structure, the laser rod 15 is connected to the internal space 1 of the reflecting cylinder 13 of the laser oscillator body 10.
4, when the rod holder 19 is supported in a watertight sealed state, the cooling water in the space portion 14 of the reflecting cylinder 13 tries to enter the inside from the inlet portion 19a of the rod holder 19.

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.

Next, in the laser rod supporting structure according to this embodiment, a mounting method for supporting the laser rod in a sealed state on the rod holder will be described. As is clear from the exploded perspective view of the structure for supporting the laser rod in the sealed state in the rod holder in the present embodiment shown in FIG. 3, first, the backup ring 22 and then two O's are provided.
-The ring 23 is sequentially connected to the inlet portion 1 of the cylindrical rod holder 19.
Insert from 9a inside.

On the other hand, a ring-shaped plug 24 having a thread portion formed on the outer circumference is loosely fitted to the end portion of the laser rod 15. After that, the laser rod 15 has a backup ring 22 and an O-ring 23 from the inlet of the rod holder 19 to the inside until the end surface of the laser rod 15 reaches the bulging portion 21.
Inserted through.

The plug 24 previously loosely fitted to the laser rod 15 is connected to the inlet portion 19a of the rod holder 19.
It is attached by being screwed into a screw portion 20 formed on the inner peripheral surface.
The backup ring 22 and the two O-rings 23 are
At this time, due to the pressure of the plug 24 entering the rod holder 19, the plug 24 is compressed by being sandwiched between the bulging portion 21 and the plug 24. As a result, the backup ring 22 and the two O-rings 23 are firmly adhered to the outer peripheral surface of the laser rod 15, so that the laser rod 15 and the rod holder 19 are watertightly sealed and supported or attached. Become.

Of course, the mounting of the laser rod 15 on the rod holder 19 in a watertight sealed state is not limited to such a procedure. For example, even if both the backup ring 22 and the two O-rings 23 are previously attached to the outer periphery of the end portion of the laser rod 15, this attachment structure can be assembled.

In order to prevent the 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 main 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.

[0037]

As described above, according to the laser rod supporting structure of the present invention, the seal member is attached to the outer peripheral portion of the end portion of the laser rod inserted inside the rod holder, and the plug is provided at the inlet portion of the rod holder. By compressing the seal member between the bulging portion of the rod holder and the water-tight seal at the laser rod mounting portion of the rod holder. Further, the backup ring prevents the laser return light from irradiating the O-ring, and as a result, the reliability of the laser oscillator main body for long-term use can be improved.

[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 support structure of the present invention is applied.

FIG. 2 is a sectional view showing a laser rod support structure according to an embodiment of the present invention.

FIG. 3 is an exploded perspective view of the laser rod support structure shown in FIG.

FIG. 4 is a partial cross-sectional view showing a conventional structure for supporting a laser rod on a rod holder in a watertightly sealed state.

[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

Claims (5)

[Claims] 1. A solid-state laser device having a structure in which a laser rod is supported by a rod holder in a watertight sealed state, and a radially inwardly bulged portion is formed at a predetermined axial position from an inlet portion of an end portion. A cylindrical rod holder, a laser rod whose end is inserted from the inlet of the rod holder, and an outer periphery of the end of the laser rod inserted from the inlet of the rod holder. A ring-shaped member and a plug fitted inside the rod holder from the inlet portion are provided, and the ring-shaped member is pressed against the bulging portion by the fitting pressure of the plug into the inlet portion of the rod holder. A laser rod support structure, characterized in that the ring-shaped member is compressed and brought into close contact with the laser rod for sealing. 2. The ring-shaped member is composed of a backup ring and at least one O-ring, and the backup ring is pressed against the bulging portion by the fitting pressure of the plug into the inlet portion of the rod holder. The laser rod support structure according to claim 1, wherein the O-ring is pressed against the backup ring and compressed together, thereby closely contacting and sealing the O-ring with the laser rod. 3. The plug is formed of a ring-shaped member having a threaded portion on its outer periphery, and the plug is loosely fitted in an end portion of the rod holder before the laser rod is inserted into the rod holder. The laser rod support structure according to claim 1 or 2, wherein the rod holder is screwed and mounted on a screw portion formed on the inner peripheral surface of the inlet portion. 4. The laser rod support structure according to claim 2, wherein the backup ring is made of Teflon resin. 5. A seal portion between the laser rod and the rod holder is located in a cooling water filling chamber in the laser oscillator body to prevent cooling water from entering the rod holder through the seal portion. Claim 1 characterized in that
2. The laser rod support structure according to 2, 3 or 4.