JPH048720B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a laser detonator that improves detonation properties by configuring the structure of the chamber for loading explosives, loading specific gravity, and constraint conditions of the chamber in a specific manner. It is something.

(Prior art) Conventionally, detonators used to detonate explosives include industrial detonators that use a fuse and electric detonators that allow current to flow through a conducting wire, but in recent years laser detonators that use laser light have been developed. ing.

A ruby laser, a YAG (yttrium aluminum garnet) laser, or the like is used as a laser oscillation device for such a laser detonator.

As a detonator that is detonated by a laser beam from the laser oscillation device, a detonator as shown in FIG. 3 is conventionally known (see US Pat. No. 3,528,372). This laser detonator 30 is
7 and a first chamber 3 defined by a plate 40.
3 and a second chamber 34, an optical fiber 39 is connected to the upper part of the explosive 31 placed in the first chamber 33 via a lens 36, and both chambers 33 and 3
4. The plate 40, the cavity 37, the lens 36 and the optical fiber 39 are surrounded by a restraining wall 38, the end of the optical fiber 39 is sealed with an embolus 35, and a multilayer structure is loaded into both chambers 33 and 34, respectively. Explosives 31 and 32 are Class 2 high-performance explosives,
The loading specific gravity of the explosive in each chamber is such that the upper part is higher than the lower part, and the specific gravity composition of both chambers is the same.

(Problems to be Solved by the Invention) Such a laser detonator has a complicated structure because it is divided into a first chamber and a second chamber, and is provided with a cavity and a plate. Since only Class 2 high-performance explosives are loaded in the part of the first chamber that comes into contact with the optical fiber, most of the laser light irradiated through the optical fiber is reflected and cannot be efficiently absorbed by the explosive. Ta. Further, since the loading specific gravity of the explosive loaded in each chamber was higher in the upper part than in the lower part, the ignition sensitivity by laser light was low in the first chamber. Additionally, since the restraining wall also exists around the second chamber, when the second chamber detonates, the power is concentrated at the bottom, which has the disadvantage that the detonation ability of the explosive in the area in contact with the restraining wall is reduced. It was hot.

In order to solve the above-mentioned problems, the present invention provides a laser detonator with a specific configuration to simplify the structure, efficiently absorb laser light, easily ignite, and ensure reliable detonation. Therefore, it is an object of the present invention to provide a laser detonator that can sufficiently detonate loaded explosives.

(Means for Solving the Problems) The present invention provides a laser detonator in which an optical fiber is brought into contact with the upper part of the explosive and a restraining wall is provided on the outside of the explosive. shall be a class 2 class high explosive containing a black laser light absorbing substance, or the explosive loaded in the upper part shall be a class 2 class high explosive containing the above laser light absorbing substance, and the explosive loaded in the middle and lower parts shall be a class 2 high explosive containing a black laser light absorbing substance. The explosives are classified as class 2 high-performance explosives,
In addition, the loading specific gravity of the explosives loaded in the lower part was made higher in the middle than in the upper part and higher in the lower part than in the middle, and only the sides of the explosives loaded in the upper part or the upper part and the middle part were surrounded by restraining walls. It is characterized by

(Function) According to the present invention, when the upper part of the explosive loaded in the laser detonator is irradiated with laser light through the optical fiber, the laser light absorbing substance contained in the explosive loaded in the upper part is heated, and the surrounding area is heated. of the explosive ignites, the combustion rate of the upper explosive surrounded by the restraining wall increases, and the pressure of the gas increases. Therefore, when the combustion progresses to the lower explosive, the pressure of the combustion gas increases enough to detonate, and the lower explosive detonates, causing the lower explosive charged with the laser detonator of the present invention to explode. The explosives surrounding the explosive detonate.

(Example) The present invention will be explained below with reference to the drawings.

FIG. 1 shows a first example of the laser detonator of the present invention. In this example, the laser detonator 1 has a bottomed tube body 2, in which the upper part of the tube body 2 is loaded with a class 2 class high explosive 4 containing a laser light absorbing substance, and the lower part is loaded with a class 2 class high explosive 4 containing a laser light absorbing substance. Load high explosive 5. At this time, the explosives 4 loaded in the upper part of the restraining wall 6 inside the tube body 2
and the upper side thereof is covered by the embolus 7. That is, the central part of the embolus 7 is penetrated by the optical fiber 8, and in this state, the embolus 7 is inserted into the tube body 2.
so that the end opening of the optical fiber 8 can come into direct contact with the explosive charge 4.

Explosives used in the laser detonator of the present invention configured as described above include, for example, PETN (pentaerythritol tetranitrate), tetryl (trinitrophenylmethyl nitramine),
RDX (trimethylene trinitramine), HMX
(cyclotetramethylenetetranitramine) and other class 2 class high-performance explosives are used. In particular, the explosive 4 loaded on the top is carbon black to efficiently absorb laser light.
Black carbon-based substances such as graphite, or dyes that have an absorption band at the laser wavelength, such as black dyes (direct first black B,
(manufactured by Sumitomo Chemical) etc. from 0.5 to
A class 2 class high explosive with 10% by weight added is used as the igniter or detonator.

For example, when PETN is used as the explosive, the loading specific gravity of the explosive loaded in the laser detonator of the present invention is usually in the range of 0.8 to 1.7, but the loading specific gravity of the explosive 4 loaded at the top is usually 0.8 to 1.4. , preferably from 0.8 to 1.2. Further, the loading specific gravity of the explosive 5 loaded at the bottom is usually selected from the range of 1.2 to 1.7. That is, the loading specific gravity is selected to be low in order to continue top-loaded combustion and to easily transition from combustion to deflagration and from deflagration to detonation. Furthermore, the explosive 5 loaded at the bottom is sufficiently detonated by the detonation wave of the explosive loaded at the top, and has the explosive power sufficient to detonate the explosive loaded with the laser detonator of the present invention. To achieve this, choose a high loading density.

The material of the restraining wall 8 is selected from metals with high tensile strength such as iron, stainless steel, copper, and aluminum, or reinforced plastics with comparable strength. Moreover, the thickness of the restraining wall 8 is
It is determined by the inner diameter of the upper chamber and the material used, but for example, if the inner diameter is 6 mm and iron is used,
It is sufficient if it is 0.1 mm or more, but it is usually in the range of 1 to 2 mm. This restraining wall 8 is used to maintain the pressure of the combusted gas when the explosive 4 loaded on the top ignites and burns. Therefore, its length should be sufficient to at least cover the sides of the explosive 4 loaded on the top. Further, although the detonating force of the explosive at the portion in contact with the side surface of the explosive 5 loaded at the bottom is weakened, the restraining wall 8 may cover even the side surface of the explosive 5 loaded at the bottom.

The tube body 2 is used as a container for loading the explosives 4 and 5, and may be made of any material and thickness that will not be deformed by the pressure during loading, such as iron, copper, aluminum, reinforced It is selected from plastics, etc. For example, in the case of copper, if the loading specific gravity of the explosive is 1.4, the thickness should be about 0.1 mm. The optical fiber 8 and the class 2 high-performance explosive 4 containing a laser light absorbing substance may be brought into direct contact with each other, or may be brought into contact indirectly through a lens.

A second example of the laser detonator of the present invention will be explained below with reference to FIG.

In this example, the laser detonator 10 has a bottomed tube body 11
The part of the upper part of the tube body 11 in contact with the optical fiber 8 is made of a Class 2 high-grade material with a laser light-absorbing material added to a length that is sufficient to ignite when it absorbs laser light, usually in the range of 1 to 15 mm. A high explosive 4 is loaded, and a class 2 high explosive 13 is loaded in the middle and lower parts. Also, the upper side of the explosive 4 is embolized 7.
covered by. At this time, an optical fiber 8 is inserted into the center of the embolus 7, and in this state, the embolus 7 is inserted into the tube body 11.
The opening at the end of the optical fiber 8 is fitted onto the upper end of the optical fiber 8 so that it can directly contact the explosive 4. Further, the outer side of the tube body 11 is surrounded by a restraining wall 6 around the upper explosive 4 and the middle explosive 13.

The operation of the laser detonator configured as above is that the explosive proceeds from the top to the middle and then to the bottom.
Since it is the same as that explained for the first example, detailed explanation thereof will be omitted.

Hereinafter, specific examples of the present invention will be explained.

Specific Example 1 A laser detonator shown in FIG. 1 was produced by the following method.

A type 2 explosive 5 is loaded into a copper tube body 2 having an outer diameter of 7.6 mm, a thickness of 0.3 mm, a length of 50 mm, and a tube bottom 3 of 0.3 mm thick, at the bottom between 10 mm from the tube bottom 3. It was loaded with PETN, a class high explosive, with a loading specific gravity of 1.40. Next, a restraining wall 6 made of iron with an inner diameter of 5.0 mm, a thickness of 1 mm, and a length of 30 mm was loaded so as to contact the explosive loaded at the bottom. Next, inside the restraining wall 8,
1% by weight of carbon braz, a laser light absorbing substance, was added as explosive 4 to be loaded on the top.
PETN was loaded with a loading specific gravity of 1.15. Next, tube body 2
The embolus 7 was inserted into the inside of the cage so as to be in contact with the restraining wall 6 and fixed by adhesion.

A quartz optical fiber 8 with a core diameter of 0.8 mm, an attenuation rate of 6 dB/Km, and a length of 30 m is connected to the laser detonator 1 shown in FIG. When irradiated with laser light from a YAG laser that generates laser light, the laser detonator 1 completely explodes, and the lead plate (40 mm x 40 mm x 4 mm) of the lead plate test specified in the Japanese Industrial Standards (JIS K4806-1978) ) was penetrated. Also,
Explosives for the blunt explosive test similarly specified by JIS (TNT: 70% trinitrotoluene, 30% talc)
The lead plate (70mm x 70mm x 30mm) was able to be completely detonated and the same level of detonation marks as a No. 6 industrial detonator were obtained.

Specific example 2 The laser explosive detonator 20 shown in FIG.
1 has an inner diameter of 6.2 mm, a thickness of 0.3 mm, and a length of 55 mm.
Using a copper detonator tube body with a tube bottom 12 of 0.3 mm,
As an explosive to be loaded at the bottom, 15mm from the bottom of the tube 12
During the period, PETN was used as a class 2 high explosive.
was loaded with a loading specific gravity of 1.40, and the middle part was filled from the bottom of the tube with 12
Loading PETN between 15mm position and 35mm specific gravity 1.15
Load it with
Tetrile to which 1% by weight of black dye (Direct First Black B, manufactured by Sumitomo Chemical Co., Ltd.), which is a laser light absorbing substance, is added is loaded between 45mm and has a specific gravity of 1.15.
Loaded with. Next, the inner diameter is 6.8 mm, the thickness is 1 mm, and the length is
It is the same as the laser detonator 1 shown in Example 1, except that the explosives loaded in the upper and middle parts are surrounded by a 40 mm steel restraining wall 6 and attached to the tube body 11 so that the lower part is not covered. When a product was prepared and the same tests as in Example 1 were conducted, similar good results were obtained.

Comparative Example 1 Conventional laser detonator 3 as shown in Figure 3
0 was created.

A glass lens 36 was inserted into a restraining wall 38 made of copper and having a length of 58 mm, an inner diameter of 6 mm, and a thickness of 1 mm. As an explosive, it is a class 2 high-performance explosive.
Using PETN, it is placed in the first chamber 33 and within 4 mm from the surface in contact with the lens 36 with a loading specific gravity of 1.40.
So, between 4mm and 10mm, I loaded it with 1.20, and between 10mm and 16mm, I loaded it with 1.10. A circular copper plate 40 with a diameter of 6 mm and a thickness of 0.3 mm was placed at the bottom of the first chamber 33 and fixed by adhesive. Next, with an empty space of 5 mm, the explosive in the second chamber 34 is loaded between 21 mm and 25 mm from the lens surface with a specific gravity of 1.40.
1.20 between 25mm and 31mm, and 1.20 between 31 and 37mm.
1.10 and loaded with PETN at 1.00 between 37mm and 43mm, respectively. The tube bottom 41 has a diameter of 8 mm and a thickness of 0.3
A copper plate having a diameter of 1 mm was adhered and fixed to the restraining wall 40. Next, an embolus 35 is inserted, an optical fiber 39 is placed,
Fixed.

In this conventional laser detonator 30, specific example 1
When irradiated with laser light in the same manner as above, it did not ignite and did not explode.

Comparative Example 2 In the conventional laser detonator of Comparative Example 1,
The same as Comparative Example 1 except that an explosive containing 1% by weight of carbon black as a laser light absorbing substance in PETN was loaded at a loading specific gravity of 1.40 as an explosive to be loaded within 4 mm from the surface of the first chamber 33 in contact with the lens 36. A sample was prepared and the same test as in Example 1 was conducted.

As a result, although this conventional laser detonator ignited, it was so weak that it did not penetrate the lead plate in the lead plate test, nor could it detonate blunt explosives.

(Effects of the Invention) The laser detonator of the present invention has the following features.

(1) While conventional laser detonators do not contain a laser light-absorbing material in the explosive loaded in the upper part that contacts the optical fiber, the laser detonator of the present invention contains a laser light-absorbing material. Therefore, it is possible to reliably ignite a laser with a small pulse width of several μs or a continuous wave laser with a small peak output other than the laser oscillation method using a Q switch with a high absorption efficiency of laser light and a pulse width of several 10 ns with a large peak output. I can do it.

(2) The explosive loaded at the top uses an explosive containing a laser light absorbing material only in the part that absorbs and ignites the laser light, and the other parts do not contain the above absorbing material. When burned, it has no ingredients other than explosives and is very powerful.

(3) In the conventional laser detonator, the loading specific gravity of the explosive is higher in the upper part than in the lower part in each of the first and second chambers, whereas in the laser detonating detonator of the present invention, the loading specific gravity of the explosive is higher in the upper part than in the lower part. By making the lower part higher, the explosive loaded in the upper part easily deflagrates and transfers from deflagration to detonation, so that the explosive loaded in the lower part can be reliably detonated.

(4) While the conventional laser detonator has a restraining wall covering the entire sides of the first and second chambers, the laser detonator of the present invention has a restraining wall that covers the entire side of the first and second chambers, whereas the laser detonator of the present invention has a restraining wall that covers the entire side of the first and second chambers. It covers only the sides,
Since the lower part is not covered, the side of the explosive loaded in the lower part also has detonating force, and the explosive loaded with the laser detonator of the present invention can be sufficiently detonated.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the laser detonator of the present invention, FIG. 2 is a sectional view of another example of the laser detonator of the present invention, and FIG. 3 is a sectional view of a conventional laser detonator. . 1... Laser detonator of the present invention, 2... Tube body, 3... Tube bottom, 4... Class 2 high performance explosive added with a laser light absorbing substance, 5... Class 2 high performance explosive. High performance explosive, 6... Restriction wall, 7... Embolus, 10... Laser detonator of the present invention, 11...
... Tube body, 12 ... Tube bottom, 13 ... Class 2 high-performance explosive, 30 ... Conventional laser detonator.

Claims (1)

[Claims] 1. In a laser detonator in which an optical fiber is brought into contact with the upper part of the explosive and a restraining wall is provided on the side of the explosive, the explosive loaded in the upper part that contacts the optical fiber is covered with a black laser light absorbing material. A Class 2 class high-performance explosive containing A laser detonator characterized by surrounding a laser detonator. 2. In a laser detonator with an optical fiber in contact with the upper part of the explosive and a restraining wall on the side of the explosive, the explosive loaded in the upper part that contacts the optical fiber is heated to High-performance explosives are used, and the explosives loaded in the middle and lower parts are Class 2 high-performance explosives, and the specific gravity of the explosives loaded in each part is set higher in the middle than in the upper part, higher in the lower part than in the middle, and restrained. A laser detonator characterized in that a wall surrounds only the sides of the explosive loaded in the upper and middle parts.