JPH1047892A - Igniting part for electric detonator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an igniting part for an electric detonator, capable of preventing accidental explosion due to electrostatic induction or the damage of electric bridge wires due to loading pressure of igniting charge surely, and further, capable of being manufactured easily. SOLUTION: The bottom surface of a spot facing 24 of an insulating body 2 made of ceramics is connected to the rear surface of inflated head 32 of a lead pin 3 through a connecting material and a gap between them is sealed while the inwardly projected flange 11 of a metallic tube 1 is connected to the other end surface 22 of the insulating body 2 made of ceramics through a connecting material and a gap between them is sealed respectively. A step between the other end surface 111 of the metallic tube 1 and the flat end surface 21 of the insulating body 2 made of ceramics as well as a step between the feat end surface 21 of the insulating body 2 and the surface 321 of inflated head of the lead pin 3 are specified so as to be not more than 100μm or preferably not more than 50μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an ignition part for an electric detonator.

[0002]

2. Description of the Related Art Blasting work, crushing of concrete buildings,
The electric detonator used for airbags for automobiles and the like has a configuration in which the opening of the metal outer cylinder is closed with an ignition part having a bridge, and an ignition agent is filled in the metal outer cylinder in contact with the bridge.
In operation, a metal outer cylinder is ruptured by igniting an igniting charge by energization and heating of a bridge wire. Depending on the configuration and operating conditions of this electric detonator, a potential difference occurs between the lead pin and the metal outer cylinder due to electrostatic induction, and a discharge occurs between the lead pin and the metal outer cylinder, As a result, a potential difference is generated between both ends of the bridge due to an electrostatic imbalance, and the potential difference may cause a current to flow through the bridge and cause an explosion.

Conventionally, as an electric detonator, as shown in FIG. 4, a distal end of a first lead pin 3 'is penetrated through a metal inner cylinder 1' using an insulating glass 2 'as a sealing material. Of the ignition component A 'having a second lead pin 5' welded thereto and a bridge 4 'connected between the distal end surface of the first lead pin 3' and the distal end surface of the inner cylinder 1 '. It is known that the metal inner cylinder 1 'is covered with the metal outer cylinder b and the metal outer cylinder b is filled with the igniting agent c. The gap between the metal outer cylinder b and the lead pins 3' and 5 'is known. Since they are electrically connected to each other with a low resistance by the metal inner cylinder 1 ′ and the bridge wire 4 ′, the explosion caused by the electrostatic induction can be advantageously eliminated.

[0004]

In sealing the metal inner cylinder 1 'with the insulating glass 2', a glass block having a lead pin insertion hole is placed in the metal inner cylinder, and the metal block is sealed.
The tip of the first lead pin is inserted into the through hole, and the glass block is melted and solidified by heating to bond the metal inner cylinder and the interface between the lead pin and the glass. However, in such a configuration, it is difficult to make the front end surface of the metal inner cylinder, the front end surface of the sealing glass, and the front end surface of the first lead pin flush, and the electric bridge wire fills the non-planar surface with the ignition agent. Since it is pressurized by pressure, there is concern about damage to the bridge. Conventionally, it has been proposed to grind with a grindstone in order to make the above-mentioned surface flush (Japanese Patent Laid-Open No. 6-185897). However, the hardness of the lead pin or metal inner cylinder is greatly different from that of the insulating glass, and the polishing rate for each member is different. Therefore, it is not easy to polish the above-mentioned surface by polishing.

An object of the present invention is to provide an ignition component for an electric detonator that can surely prevent the explosion caused by the electrostatic induction and the damage to the bridge bridge due to the charging pressure of the igniter, and that can be easily manufactured. is there.

[0006]

According to one aspect of the present invention, there is provided an ignition component for an electric detonator according to the present invention, comprising: a metal tube having an inwardly projecting flange on an inner periphery of one end of a cylindrical portion; and a metal tube mounted in the metal tube. An end surface facing the other end of the ceramic insulator is a flat surface, a lead pin insertion hole penetrates from the end surface to the other end surface, and a counterbore portion is provided at an insertion opening of the insertion hole; A lead pin having a pin portion inserted through the lead pin insertion hole and a bulging head housed in the counterbore portion;
An electric bridge wire connected between the other end surface of the metal cylinder and the surface of the bulging head of the lead pin, wherein the bottom surface of the counterbore of the ceramic insulator and the back surface of the bulging head of the lead pin are provided; And between the inwardly projecting flange of the metal tube and the other end surface of the ceramic insulator are joined and sealed with a bonding material, respectively, and the other end surface of the metal tube is Although there is a step between the flat end surface of the ceramic insulator and a step between the flat end surface of the ceramic insulator and the bulging head surface of the lead pin, the step is 100 μm or less, preferably 50 μm or less. Have been.

Another ignition part for an electric detonator according to the present invention is:
A metal cylinder having an inwardly projecting flange on the inner periphery of one end of the cylinder, and an end face that is mounted in the metal cylinder and faces one end of the metal cylinder is a flat surface. A stepped portion engaged with the inwardly projecting flange, a ceramic insulator having a lead pin insertion hole penetrating from the same end face to the other end face, and a pin inserted through the lead pin insertion hole; And a lead pin having a flange portion locked to the other end surface of the ceramic insulator, and a bridge wire connected between an end surface on one end side of the metal cylinder and a tip end surface of the lead pin. And a joining material for joining between the flange of the lead pin and the other end surface of the ceramic insulator, and between the inwardly projecting flange of the metal cylinder and the step of the ceramic insulator. The metal tube has an inward protrusion. Tsubagaimen the ceramic insulator of the flat end surface and re stepped and ceramic insulator between the flat end face - also present is a step between the tip end surface of the Dopin,
The step is set to 100 μm or less, preferably 50 μm or less.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing an example of one electric detonator ignition component according to the present invention. In FIG. 1, reference numeral 1 denotes a metal inner cylinder, which has an inwardly projecting flange 11 on the inner periphery of one end of the cylinder. Reference numeral 2 denotes a ceramic insulator, one end surface 21 of which is flat, a lead pin insertion hole 23 penetrating from the one end surface 21 to the other end surface 22, and a counterbore 24 is formed at an insertion opening of the insertion hole 23. Is provided. Reference numeral 3 denotes a lead pin having a pin portion 31 and a bulging head 32. In this lead pin 3, the pin portion 31 is inserted through the lead pin insertion hole 23 of the ceramic insulator 2, the bulging head 32 is accommodated in the counterbore portion 24, and the bulging head back surface and the counterbore bottom surface are provided. Is a bonding material 41, for example,
Bonded and sealed with a low melting point metal film. Further, in the ceramic insulator 2, the joining material 42 is accommodated in the metal inner cylinder 1, and a space between the inner surface of the inwardly projecting flange 11 of the inner cylinder 1 and the other end surface 22 of the ceramic insulator 2 is formed. Are bonded and sealed by a low melting point metal film. A step between one end face 21 of the ceramic insulator 2 and one end face 111 of the metal inner cylinder 1 and the ceramic insulator 2
There is a step between the one end surface 21 of the lead pin and the outer surface 321 of the lead pin bulging head 32, and the step is 100 μm or less, preferably 50 μm or less.

Reference numeral 4 denotes a bridge bridge connected by welding or the like between one end surface 111 of the metal inner cylinder 1 and the outer surface 321 of the lead pin bulging head 32. Reference numeral 5 denotes a return-side lead pin welded to the other end surface of the metal inner cylinder 1. For the electric bridge wire 4, a single metal wire such as iron, nickel, molybdenum, platinum, tungsten, tantalum or the like having a normal wire diameter of 20 to 50 μm, or an alloy wire such as nickel-chromium or iron-chromium-aluminum is used. Is done. The metal inner cylinder 1 and the lead pin 3 are made of copper,
Iron, stainless steel, etc. are used.

In the above, the joining and sealing of the ceramic insulator 2 and the metal inner cylinder 1 and the lead pin bulging head 3
For example, the bonding / sealing between the ceramic insulator 2 and the ceramic insulator 2 includes, for example, an intermediate layer (for example, Mo-M) firmly bonded to the ceramic at the other end face and the counterbore of the ceramic insulator.
manganese aluminate layer by the n method), and a metal such as copper, tin, etc., which is easy to solder, is plated on this intermediate layer,
A method can be used in which a sheet-like solder is interposed at the joint interface, and both joints and seals are performed at once by hot pressing. When the ceramics are alumina ceramics, they can be directly joined by heat pressure welding with sheet-like aluminum solder without forming an intermediate layer. In this case, the depth of the metal inner cylinder 1, the height of the ceramic insulator 2, the ceramic insulator 2
The processing tolerances such as the depth of the counterbore portion 24, the thickness of the bulging head 32 of the lead pin 3, and the difference in the thermal expansion coefficient of the metal inner cylinder, the lead pin, the ceramic insulator, and the solder. Due to the difference in thermal strain based on the above, between the one end surface 21 of the ceramic insulator 2 and the one end surface 111 of the metal inner cylinder 1, and between the one end surface 21 of the ceramic insulator 2 and the tip of the lead pin. There is a step between the outer surface 321 and the step.
It is easy to fit within 0 μm, preferably within 50 μm.

In the above embodiment, the return-side lead pins 5 are welded to the metal inner cylinder 1, and the insulated wires 63 and 65 are connected to the respective lead pins 3 and 5, as shown in FIG. On the return side, the insulated wire 65 can be directly connected to the metal inner cylinder 1.

FIG. 3 is an explanatory view showing an example of another ignition component for an electric detonator according to the present invention. In FIG. 3, reference numeral 1 denotes a metal inner cylinder having an inwardly projecting flange 110 on the inner periphery of one end of the cylinder. Reference numeral 2 denotes a ceramic insulator, one end surface 21 of which is a flat surface.
A lead pin insertion hole 23 extends from one end surface 21 to the other end surface 22 of the same. 3 is a lead pin having a pin portion 31 and a flange portion 33. This Lee
Copper or iron or the like is used for the doping 3 and the metal inner cylinder 1 as described above. In the lead pin 3, the pin portion 31 is inserted into the lead pin insertion hole 23 of the ceramic insulator 2, and the flange portion 33 is connected to the other end face 22 of the ceramic insulator 2.
And the contact interface is joined and sealed by a joining material 42, for example, a low melting point metal film. Further, in the ceramic insulator 2, the joining material 410 is accommodated in the metal inner cylinder 1, and a space between the inner surface of the inwardly projecting flange 110 of the inner cylinder 1 and the step portion 240 of the ceramic insulator 2, for example, Are bonded and sealed by a low melting point metal film. One end flat surface 21 of this ceramic insulator 2 and metal inner cylinder 1
There is a step between the one end surface 111 and the one end flat surface 21 of the ceramic insulator 2 and the tip end surface 311 of the lead pin 3, but the step is 100 μm or less, preferably 50 μm. It is as follows.

Reference numeral 4 denotes an electric bridge line connected by welding or the like between the one end surface 111 of the metal inner cylinder 1 and the tip end surface 311 of the lead pin 3, and has a wire diameter of usually 20 to 50 μm as described above. A single metal wire such as iron, nickel, molybdenum, platinum, tungsten, tantalum or the like, or an alloy wire such as nickel-chromium or iron-chromium-aluminum is used. It is a side lead pin.

[0014] The step of the ceramic insulator is joined to the inwardly projecting flange of the metal inner cylinder. The seal and the flange of the lead pin are joined to the other end face of the ceramic insulator. For example, as in the above embodiment, an intermediate layer is formed on the ceramic insulator portion at the bonding interface, a metal which is easily soldered is plated on the intermediate layer, and a seal is formed on the bonding interface.
A method in which both joints and seals are formed at a time by thermal pressure welding with interposed solder, a method in which both joints and seals are formed at once by heat and pressure welding with a sheet-like aluminum solder without providing an intermediate layer Can be used. In this case as well, tolerances in processing such as the thickness of the inwardly projecting flange of the metal inner cylinder, the height of the step portion of the ceramic insulator, the height of the ceramic insulator, and the length of the lead pin portion, and the like. Between the flat surface of the ceramic inner cylinder and one end surface of the metal inner cylinder due to the difference in thermal strain based on the difference in the coefficient of thermal expansion of the metal inner cylinder, the lead pin, the ceramic insulator, and the solder. , Flat surface of ceramic insulator
There is a step between the tip of the pin and the pin.
It is easy to keep this step within 100 μm, preferably within 50 μm.

The ignition component according to the present invention is used by hermetically covering the opening of the metal outer cylinder in the metal inner cylinder of the ignition component and filling the metal outer cylinder with an igniting agent. In this case, since the metal outer cylinder and the lead pins 3 and 5 are electrically connected with low resistance by the metal inner cylinder 1 and the electric bridge wire 4, etc., it is possible to eliminate the explosion caused by the electrostatic induction. . In addition, the electric bridge is pressurized by the charging pressure of the igniting agent, but the end surface of the ceramic insulator to which the electric bridge is pressed is flat, and the step between the flat surface and the end end of the lead pin is formed. And the step between the flat surface and one end surface of the metal inner cylinder is 100
Since it is set to be not more than μm, preferably not more than 50 μm (less than the dimension substantially equal to the outer diameter of the bridge wire), it is possible to sufficiently prevent the breakage by only bending the bridge wire at the step. Furthermore, the igniting agent is kept airtight to the outside by the joining and sealing between the ceramic insulator and the metal inner cylinder, the sealing and the joining between the tip of the lead pin and the ceramic insulator. In addition, the igniting agent can be stably held without humidification or deterioration. Therefore, reliable operation and excellent reliability can be guaranteed. In the ignition component according to the present invention, the step on the surface where the bridge wire contacts is suppressed to 100 μm or less, preferably 50 μm or less, based on the normal processing tolerance of each member such as a metal inner cylinder, a ceramic insulator, and a lead pin. It is a configuration that can be obtained and is easy to manufacture.

[0016]

In the ignition component for an electric detonator according to the present invention, even if a step is formed on the surface in contact with the electric bridge line due to the structure, the step is reduced to 100 μm by the normal processing tolerance of the member.
m, preferably 50 μm or less. Therefore, according to the present invention, it is possible to provide an ignition part for an electric detonator that is easy to manufacture without fear that the electric bridge wire will be damaged by the charging pressure of the ignition charge.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an example of an electric detonator ignition component according to claim 1;

FIG. 2 is an explanatory view showing another example of the ignition component for an electric detonator according to claim 1.

FIG. 3 is an explanatory view showing an example of an electric detonator ignition component according to claim 2;

FIG. 4 is an explanatory diagram showing a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 metal inner tube 11 inwardly projecting flange 110 inwardly projecting flange 2 ceramic insulator 21 flat surface 24 counterbore 240 step 3 lead pin 31 pin 32 bulging head 33 flange 41 bonding material 42 bonding material 410 bonding Material 4 Denbashi Line

Claims (3)

[Claims] 1. A metal cylinder having an inwardly projecting flange on the inner periphery of one end of a cylinder, and an end face mounted in the metal cylinder and facing the other end of the metal cylinder is a flat surface. A ceramic insulator having a lead pin insertion hole penetrating the end face, and a counterbore portion provided in the insertion opening of the insertion hole; a pin portion inserted into the lead pin insertion hole and the counterbore portion A lead pin having a bulging head accommodated in the metal cylinder, and a bridge wire connected between the other end face of the metal cylinder and the surface of the bulging head of the lead pin. The bottom surface of the counterbore and the back surface of the bulging head of the lead pin and the space between the inwardly projecting flange of the metal cylinder and the other end surface of the ceramic insulator are bonded and sealed with a bonding material. An ignition part for an electric detonator characterized by the above-mentioned. 2. A metal cylinder having an inwardly projecting flange on one inner end of a cylindrical part, and an end face mounted in the metal cylinder and facing one end of the metal cylinder is a flat surface. Is provided with a step engaged with the inwardly projecting flange of the metal cylinder,
A ceramic insulator having a lead pin insertion hole penetrating from the same end face to the other end face; a pin portion inserted into the lead pin insertion hole; and a flange locked to the other end face of the ceramic insulator. A lead pin having a portion, and a bridge wire connected between an end face on one end side of the metal cylinder and a tip end face of the lead pin, wherein a flange of the lead pin and a ceramic insulator are provided. An ignition part for an electric detonator, characterized in that a gap between an end face and a gap between the inwardly projecting flange of the metal cylinder and the step of the ceramic insulator are joined and sealed with a joining material. 3. A step between the flat end face of the ceramic insulator and the end face of the lead pin and a step between the flat end face of the ceramic insulator and the end face of the metal cylinder are 100 μm or less. Ignition parts for electric detonators.