JP2945173B2 - Postponed laser detonator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a detonation laser detonator detonated by laser light transmitted through an optical fiber, and more particularly to a detonation laser detonation detonator capable of reliably detonating even with low energy.

[0002]

2. Description of the Related Art Conventionally, an industrial detonator using a squib and an electric detonator detonated by electric current have been known as detonators. Recently, a laser detonator using an optical fiber has been developed. For example, as a detonator detonated by laser light, a detonator detonated by a YAG (yttrium aluminum garnet) laser oscillation device is disclosed in
No. 273800. As shown in FIG. 3, the laser detonator described in the above-mentioned patent document uses the explosive 3 mounted on the upper part in contact with the optical fiber 2 as a second class high-performance explosive containing a black laser light absorbing substance. ,
In addition, the specific gravity of the explosive 4 loaded at the lower portion is made higher than that of the explosive 3 loaded at the upper portion, and only the side surface of the explosive 3 loaded at the upper portion is surrounded by the restraining wall 5.

[0003]

The above-described conventional laser detonator has the following two problems. Part 1
Requires a high energy of about 2.5J to detonate, so a laser oscillating device of a size that can be practically handled at a blast site using a laser detonator, in view of its laser light output, The number of laser detonators that can be simultaneously detonated by laser light is limited. Second, since it has only a function as an instantaneous detonator, its use range is limited. In view of the above-mentioned problems of the prior art, an object of the present invention is to provide a delayed laser detonator detonated by a low-energy laser beam and having a delay mechanism for detonation.

[0004]

[Means for Solving the Problems] After research, the present inventor placed a charge transfer agent, which is a mixture mainly composed of an oxidizing agent and a reducing agent, on top of an explosive to ignite with low-energy laser light. And, by inclining the upper end surface of the restraining wall outward and upward, the heat is propagated from the explosive charge and the delaying material so that the explosive in the restraining wall is reliably and postponedly shifted from deflagration to detonation. I found that I got it.

[0005] Based on this finding, the above object has been achieved by a configuration having the following features according to the present invention. That is,
Its features are: a tubular container whose upper opening is closed by an embolus; an optical fiber introduced into the tubular container through the embolus to transmit the laser light; and placed below the end face of the optical fiber in the tubular container. And an inner tube having a constraining wall composed of a tubular longitudinal wall, the upper end face of the constraining wall forms a funnel-shaped annular surface having an opening area that increases upward, thereby forming a tubular container. Extend to the inner wall,
In the tubular container, in order from the end face side of the optical fiber toward the bottom of the tubular container, a transfer agent layer, a spreading agent layer, an upper explosive layer,
And a lower explosive layer. The explosive layer has an oxidizing agent and a reducing agent as main components, and has a compounding ratio of black, gray, or brown in a range of 5: 5 to 9: 1. The explosive charge of the mixture is loaded, the end face of the optical fiber is opposed to the upper surface of the explosive charge layer, the spreading medicine layer is loaded with the spreading medicine, and the lower explosive layer located below it Is located below the upper edge of the upper end face of the constraining wall in contact with the inner wall surface of the tubular container, and the upper explosive layer is a second class of the second class loaded in the inner tube to almost the lower end of the constraining wall. The lower explosive layer is composed of a high-class explosive, and the lower explosive layer is composed of a second class of high explosives loaded so that its specific gravity is greater than that of the upper explosive layer.

Hereinafter, the configuration of the present invention will be described in more detail with reference to the accompanying drawings. FIG. 1 is a schematic sectional view of a laser detonator 10 according to the present invention. The laser detonator 10 includes a tubular container 12 as a container for storing explosives and the like. The tubular container 12 is an elongated tubular container having an opening 14 at the top and a closed bottom. The cross-sectional shape of the tubular container 12 is generally cylindrical, but there is no particular limitation, and an elliptical shape, a square shape, or the like can be freely used depending on the application. Can be set. The material of the tubular container 12 used in the present invention is selected from copper, iron, aluminum, reinforced plastic, and the like, and the length, diameter, and wall thickness can be arbitrarily set according to the application, the amount of explosive, and the like. The upper opening 14 of the tubular container 12 is tightly closed by an embolus 16. In order to introduce laser light from an external laser light oscillation device into the tubular container 12, an optical fiber 18 connected to the laser light oscillation device passes through a through hole provided at a substantially central portion of the embolus 16 and has a substantially tubular shape. It is introduced into the upper space of the tubular container along the center line of the container 12. The material and size of the embolus 16 are arbitrary as long as the embolus 16 can fix and hold the optical fiber 18 to the tubular container 12.

[0007] Inside the tubular container 12, an inner tube 22 having a constraining wall 20 formed of a tubular longitudinal wall is disposed below an end face 26 of the optical fiber 18. Restraint wall 2
The upper end surface 24 of the tube 0 forms a funnel-shaped annular surface whose opening area increases upward and extends to the inner wall surface 25 of the tubular container. The inclination angle of the generatrix of the annular surface of the upper end surface 24 is preferably 30 to 70 ° above the horizontal plane, and most preferably 55 to 65 °. The inner tube 22 is connected to the tubular container 12
And may be mounted in the tubular container 12 or formed integrally with the tubular container 12. The material of the inner tube 22 is selected from iron, stainless steel, copper, aluminum, reinforced plastic, and the like.
The thickness and length of 0 are determined by the inner diameter and volume of the medicine chamber and the material used. In the case of an iron restraining wall with an inner diameter of 4.5 mm, the wall thickness should be 0.5 mm or more and the length should be 30 mm or more. The optical fiber 18 used in the present invention is not particularly limited, and a commercially available optical fiber made of a material such as quartz or resin can be used, and the core diameter and the length from the laser light oscillation device to the tubular container 12 are arbitrary.

As will be described in detail below, the laser detonator 10 according to the present invention includes a charge transfer layer 30 in the above-described tubular container 12 sequentially from the end face 26 of the optical fiber 18 toward the bottom of the tubular container 12. , An extended explosive layer 32, an upper explosive layer 34, and a lower explosive layer 36. The explosive charge is loaded in the explosive charge layer 30, and the upper surface thereof is the optical fiber 1
8 are oppositely contacting or spaced apart by a slight gap. End face 26 of optical fiber 18
The gap between the layer and the upper surface of the transfer charge layer 30 can be arbitrarily set according to the intensity of the laser beam and the core diameter of the optical fiber, but is preferably 0 to 10 mm, and most preferably 4 to 8 mm. In the optimal range of the gap, it is possible to ignite with lower energy laser light. Under the explosive charge layer 30, an extended charge layer 32 is loaded, and the explosive charge layer 30 and the extended charge layer 3 are loaded.
2 is located above the upper peripheral edge 28 of the upper end surface 24 of the restraining wall 20. The boundary surface between the extended charge layer 32 and the lower upper explosive layer 34 is located below the upper peripheral edge 28 of the upper end surface 24 of the restraining wall 20. If the boundary surface between the extended explosive layer 32 and the upper explosive layer 34 is located above the upper peripheral edge 28, the upper explosive layer 34 may not be ignited smoothly from the extended explosive layer 32.

The explosive charged in the explosive charge layer 30 mainly includes an oxidizing agent and a reducing agent, and the mixing ratio of the oxidizing agent and the reducing agent is 5:
Mixtures exhibiting a black, gray or brown color ranging from 5 to 9: 1. Since the transfer charge has a black, gray or brown color, the transfer charge substantially absorbs the laser beam transmitted through the optical fiber 18 with little reflection, and easily ignites by the absorbed energy. To prepare a black, gray, or brown explosive, an oxidizing agent such as a metal oxide such as lead red, cupric oxide, ferric oxide, barium peroxide, or lead chromate is used. And, as the reducing agent, metal or alloy powder, for example, silicon iron,
Silicon, potassium borofluoride, aluminum, and antimony trisulfide are used. Examples of the combination of the oxidizing agent and the reducing agent include, for example, leadtan-siliconiron-3antimony leadleadtan-siliconiron-ferric oxide leadtan-silicon leadtan-silicon-potassium borofluoride cupric aluminum-aluminum Ferric oxide-silicon peroxide-magnesium peroxide and the like. As the delay medicine loaded into the delay medicine layer 32, a known delay medicine used for a delay electric detonator or a delay industrial detonator is used. This type of delaying agent is composed of a mixture mainly composed of an oxidizing agent and a reducing agent, as in the case of the transfer charge, and maintains a delayed time by the burning time. On the other hand, the transfer charge of the transfer charge is short and the ignitability is high. As with the transfer charge, the oxidizing agent used in the postponed medicine is a metal oxide, for example, barium peroxide, lead tin, lead chromate, etc., and the reducing agent is a metal or alloy powder, such as silicon iron, Antimony trisulfide or the like is used, and the mixing ratio of the oxidizing agent and the reducing agent is larger than that of the transfer agent, and is preferably 1: 9 to 9: 1.

A high-class explosive of the second class is loaded as an upper explosive layer 34 in the inner tube 22 near the lower end 29 of the constraining wall 20 under the spreading agent layer 32. Second
See Anon. Ordn. Tech. Term
Explosives as defined in (1962), 267-L, for example PE
TN (pentaerythritol tetranitrate), tetrile (trinitrophenylmethylnitroamine), R
DX (trimethylenetrinitroamine), HMX (cyclotetramethylenetetranitramine), TNT (trinitrotoluene), pentrite (a mixture of PETN and TNT) and the like are used. The reason for limiting the explosives to the second class is to exclude explosives that are dangerous for security such as DDNP. The loading specific gravity of the upper explosive layer is 0.8 ~
It is selected within the range of 1.4, preferably within the range of 1.0 to 1.3. As shown in FIG. 2, when the upper explosive layer 34 in the constraining wall is multi-layered, and the specific gravity is gradually increased toward the lower layer, the detonation performance is further improved. Below the upper explosive layer 34, a lower explosive layer 36 is loaded so that its loading specific gravity is larger than that of the upper explosive layer 34. If the loading specific gravity of the lower explosive layer 36 is smaller than the loading specific gravity of the upper explosive layer 34, the detonation may be interrupted. The detonation is smoothly transferred to the lower explosive layer 36. The second class of high explosive used for the lower explosive layer 36 is, for example, P
Select and use from ETN, tetrile, RDX, HMX, TNT, pentrite and the like. The loading specific gravity is set in the range of 1.0 to 1.7, preferably in the range of 1.2 to 1.7, so as to be higher than the loading specific gravity of the upper explosive layer 34.

[0011]

According to the above-mentioned structure of the present invention, when laser light is irradiated from the laser light oscillating device through the optical fiber, the transfer charge loaded on the upper portion is heated and ignited, and then the spreading agent of the next layer is ignited. The explosive in the upper explosive layer in the restraint wall ignites due to the ignition of the explosive and postponed medicine, and the blast detonates and transfers to detonation. The detonation of the explosive in the upper explosive layer also causes the explosive at the bottom to detonate, thereby achieving sufficient power to detonate dynamite and hydrous explosives. More specifically, the explosive loaded at the top is easily ignited by a low energy laser beam to sequentially detonate the lower explosive layer, while the explosive layer, the spreading layer, the upper explosive layer and the lower explosive layer The configuration forms a delay mechanism for the detonation action. Further, the upper end surface of the restraining wall is inclined outward and upward, so that the explosive in the restraining wall can be ignited from the explosive and the delaying agent smoothly.

[0012]

EXAMPLES Hereinafter, the present invention will be described more specifically based on examples. Example 1 An extended laser detonator according to the present invention shown in FIG. 1 was manufactured as described below. A copper tube having an outer diameter of 6.5 mm, a thickness of 0.3 mm, and a length of 65 mm is used as the tubular container 12, and PETN is formed as a lower explosive layer 36 at the bottom of the tubular container 12.
(150 mesh pass) 200 mg was loaded at a loading specific gravity of 1.40. Next, a restraining wall 2 with an outer diameter of 5.9 m, a thickness of 1 mm, and a length of 35 mm
0 was inserted into the tubular container 12, and the lower end of the inner tube 22 was placed in contact with the upper surface of the lower explosive layer 36. The upper end surface 24 of the inner tube 22 is formed in a funnel-shaped annular surface whose opening area is enlarged upward and extends to the inner wall surface 25 of the tubular container 12, and the generatrix of the surface faces outward with respect to the horizontal plane. Inclined 45 ° upward. Next, as the upper explosive layer 34, PETN is inserted into the inner tube 22.
(150 mesh pass) 600 mg was loaded at a loading specific gravity of 1.20. The upper surface 34 of the upper explosive layer was located substantially at the lower periphery of the upper end face of the restraining wall 20. Next, the time delay medicine layer 32
300 mg of a spreader consisting of a mixture of lead red, silicon iron and antimony trisulfide in a weight ratio of 62.00%, 6.00% and 32.00%, respectively, was pressed and charged.

Further, as the charge transfer layer 30, 250 mg of a transfer charge composed of a mixture of lead red, silicon iron and antimony trisulfide, each of which is 71.43%, 2.30% and 26.19%,
I loaded it. Next, one end of the quartz optical fiber 18 having a core diameter of 0.4 mm and a length of 30 m is introduced into the tube through the through hole of the rubber plug 14, and fixed so that the end surface 26 thereof is in contact with the upper surface of the transfer charge layer 30, Example 1 An extended laser detonator according to the present invention was manufactured in Example 1. The thus obtained extended laser detonator of Example 1 was irradiated with laser light from a YAG laser device through a 30 m-long quartz optical fiber 18, and the detonation performance was determined by a lead plate test specified in JIS K4806-1978. It was confirmed. The test was performed five times with irradiation energy of 0.20 J and 0.15 J, respectively.
In J, all explosions occurred, and in 0.15J, only one explosion occurred.
Further, as a result of conducting a blunt explosive test specified in the JIS at 0.20 J, it was possible to obtain blast marks similar to those of the No. 6 industrial detonator.

Embodiment 2 The present invention is carried out in the same manner as in Embodiment 1 except that the quartz optical fiber 18 is fixed with the rubber plug 16 at the position where the end face 26 of the quartz optical fiber 18 is separated from the upper surface of the explosive charge layer 30 by 6 mm. Example 2 of such a delayed laser detonator was produced. The ignition performance of the extended laser detonator of Example 2 obtained in this manner was confirmed in the same manner as in Example 1.
As a result of five experiments with irradiation energy of 0.15 J,
Five explosions were completed. As a result of conducting the blunt explosive test specified in the JIS at an irradiation energy of 0.15 J, 6
Bomb scars comparable to the No. industrial detonator were obtained.

Example 3 The upper explosive layer in the constraining wall 20 was squeezed into four layers and loaded in multiple layers, and the specific gravity was 1.20, 1.15,
Example 1 except that the filling was performed to 1.05 and 1.00.
Example 3 of the extended laser detonator according to the present invention was produced in the same manner as in Example 1. The detonation performance of the extended laser detonator of Example 3 thus obtained was confirmed in the same manner as in Example 1. The experiment was performed five times at an irradiation energy of 0.15 J. As a result, all five explosions were completed. As a result of performing the blunt explosive test specified in the JIS at an irradiation energy of 0.15 J, a blast mark larger than the No. 6 industrial detonator could be obtained.

Comparative Example 1 A conventional laser detonator shown in FIG. 3 was prepared by the following method. A copper tube 1 having an outer diameter of 7.6 mm, a thickness of 0.3 mm and a length of 50 mm was loaded with 200 mg of PETN (150 mesh pass) as a lower explosive layer 4 by squeezing at a loading specific gravity of 1.40. Next, a 1 mm thick, 30 mm long iron restraining wall 5 is inserted, and PETN in which 1% by weight of carbon black as a laser light absorbing substance is added to the inside of the restraining wall 5 as an upper explosive layer 3.
(150 mesh pass) 600 mg was loaded at a loading specific gravity of 1.15. Next, one end of a quartz optical fiber 2 having a core diameter of 0.4 mm and a length of 30 m was fixed with a rubber plug 6 so that the end face thereof was in contact with the explosive surface, thereby producing a laser detonator of Comparative Example 1. The detonation performance of the laser detonator of Comparative Example 1 thus obtained was confirmed in the same manner as in Example 1. The experiment was performed five times at an irradiation energy of 0.20 J. As a result, none of the five experiments was non-explosive. A laser beam with an irradiation energy of 2.5 J was required to complete all five explosions.

COMPARATIVE EXAMPLE 2 The upper end face 24 is not inclined, that is, the flat upper end face 2
Example 1 except that a restraining wall 20 having a four was used.
A laser detonator according to Comparative Example 2 was manufactured in the same configuration as described above. The firing performance of Comparative Example 2 thus obtained was confirmed in the same manner as in Example 1. As a result of performing five experiments with irradiation energy of 0.20 J, only two explosions were completed.

From the comparison between the embodiment and the comparative example, the comparative example 1
That is, the conventional laser detonator requires 2.5J to detonate.
The laser detonation detonator of the example was able to be detonated with the laser irradiation energy of 0.2 J, while the laser irradiation energy of 0.2 mm was required. From the comparison between Example 1 and Comparative Example 2, the upper end face of the restraining wall is formed into a funnel-shaped annular surface having an opening area increasing upward, so that explosives in the restraining wall can be reduced from the explosive charge and the spreading agent. It was confirmed that the ignition of the gas could be performed smoothly. The laser detonator according to the second embodiment, in which there is a gap of 6 mm between the end face of the optical fiber and the upper surface of the explosive charge layer, has the laser of the first embodiment in which the end face of the optical fiber is in contact with the upper surface of the explosive charge layer. It can be detonated with 0.15J irradiation energy, which is even lower than the detonator. According to the results of the blunt explosive test, Example 3 of the loading structure in which the upper explosive layer in the constraining wall has a multilayer structure and the specific gravity of the upper explosive layer gradually increases toward the lower layer is the laser detonator of Examples 1 and 2. In comparison, it was confirmed that the upper explosive layer smoothly transitioned from deflagration to detonation, and had higher detonation performance.

[0019]

The delayed laser detonator according to the present invention comprises:
With a configuration in which the primer layer, the delay layer, and the explosive layer are loaded in multiple layers in a primer vessel of a specific structure, it detonates with a laser beam of extremely low energy compared to a conventional laser detonator,
And it has a reliable postponement function for detonation action and high detonation performance. Therefore, the present invention significantly increases the number of simultaneous laser detonators at the blast site and contributes to the efficiency of the blasting operation, and the required number of detonators can be reduced due to high detonation performance. And the effect of enhancing the safety of the blasting work is exerted by the delay mechanism.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an example of an extended laser detonator according to the present invention.

FIG. 2 is a schematic cross-sectional view showing an example of an extended laser detonator in which the explosive loading structure in the restraining wall is multi-layered and the detonation performance is improved.

FIG. 3 is a sectional view of a conventional laser detonator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tube 2 Optical fiber 3 Explosive containing an absorbing substance 4 Explosive 5 Restriction wall 6 Embolus 10 Delayed laser detonator 12 Tubular container 14 Top opening 16 Embolism 18 Optical fiber 20 Restriction wall 22 Inner tube 24 Upper end face of restriction wall 25 Tubular Inner wall surface of container 26 End face of optical fiber 28 Upper edge of upper end face of constraining wall 29 Lower end of constraining wall 30 Explosive layer 32 Spreading agent layer 34 Upper explosive layer 36 Lower explosive layer

Continued on the front page (72) Inventor Mikio Takano 2-22-10-1002 Kita-ku, Kita-ku, Tokyo (72) Inventor Toshikazu Miyajima 9-1-10, Minamirinma, Yamato-shi, Kanagawa Prefecture (72) Inventor Toshifumi Sato Kanagawa Prefecture 5-18-9 Sagamihara, Sagamihara-shi (56) References JP-A-63-273800 (JP, A) JP-A-62-123299 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB Name) F42B 3/113

Claims (3)

(57) [Claims] 1. A tubular container having an upper opening closed by an embolus, an optical fiber penetrating the embolus into the tubular container for transmitting a laser beam, and an end face of the optical fiber in the tubular container. Located below,
An inner tube having a constraining wall consisting of a tubular longitudinal wall, wherein an upper end surface of the constraining wall forms a funnel-shaped annular surface having an opening area that increases upward and forms an inside of the tubular container. Extending to the wall surface, in the tubular container is sequentially loaded from the end face side of the optical fiber toward the bottom of the tubular container, the explosive charge layer, the extended charge layer, the upper explosive layer, and the lower explosive layer, The explosive charge layer is loaded with an explosive charge composed of a black, gray, or brown mixture having an oxidizing agent and a reducing agent as main components, and having a compounding ratio in the range of 5: 5 to 9: 1. The end face of the optical fiber is opposed to the upper surface of the explosive charge layer, the spread medicine layer is loaded with a spread medicine, and the boundary surface with the upper explosive layer located thereunder is Located below the upper edge of the upper end face of the restraining wall, The upper explosive layer is composed of a high-class explosive of the second class loaded in the inner tube to almost the lower end of the restraining wall, and the lower explosive layer has a loading specific gravity higher than that of the upper explosive layer. A deferred laser detonator comprising a class II high explosive loaded to be large. 2. The laser detonator according to claim 1, wherein the distance between the end face of the optical fiber and the upper surface of the explosive charge layer facing the end face is 4 to 8 mm. 3. The detonation laser detonator according to claim 1, wherein the upper explosive layer comprises a multi-layer explosive layer whose loading specific gravity is sequentially increased toward a lower layer.