JP2010084980A - Airtight terminal for igniter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To smoothen the whole surface of a first main face by polishing only a part of the first main face of an airtight terminal for an igniter, and to reduce costs. <P>SOLUTION: This airtight terminal for the igniter includes an annular rising section formed around a through-hole 2 of the metallic base first main face 1a, and an elevated section having a sealing glass top section 3a and an insulating lead top section 4a on a face of the same height as a top section of the rising section. The elevated section is selectively ground and polished, so that the whole face of the first main face of the airtight terminal for the igniter comprising the metallic base first main face 1a, the sealing glass top section 3a, and the insulating lead top section 4a is smoothened. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a safety device such as an air bag or a pretensional seat belt mounted on a vehicle, and more particularly to an airtight terminal for an ignition device used in an ignition device for operating them.

  As a conventional hermetic terminal for an igniter, an insulating lead that is inserted into a through hole of a metal base with a through hole penetrating the front and back and insulated from the metal base through a glass plug is held. A base lead is erected on the surface, and an upper surface that is the opposite surface of the surface on which the base lead of the base is erected, a glass plug upper surface, and an insulating lead tip surface are formed on the same surface. (For example, see Patent Document 1).

  FIG. 4 shows an example of a conventional airtight terminal for an ignition device described in Patent Document 1 and an example of an ignition device using the same. FIG. 4A shows an airtight terminal for an ignition device, and FIG. ) Shows an example of an ignition device.

  In FIG. 4, 100 is an airtight terminal for an ignition device, 101 is a metal base, 101a is a metal base upper surface, 102 is a through hole, 103 is a glass plug, 103a is a glass plug upper surface, 104 is an insulation lead, 104a is an insulation lead tip surface , 105 is a base lead, 106 is an ignition bridge, 107 is gunpowder, and 108 is a cap.

  An ignition device hermetic terminal 100 shown in FIG. 4A has a metal base 101 having a through-hole 102 penetrating the front and back, and is inserted into the through-hole 102 from the base 101 through a glass plug 103. The insulated insulating lead 104 is held on the metal base 101, the base lead 105 is erected on one main surface of the metal base 101 by electric welding or the like, and the surface of the base 101 on which the base lead 105 is erected is opposite The metal base upper surface 101a, which is the side main surface, the glass stopper upper surface 103a, and the insulating lead tip surface 104a are formed on the same A surface.

  The above-mentioned airtight terminal 100 for an ignition device generally has an ignition bridge 106 made of an electric resistor such as a nichrome wire between an insulating lead tip surface 104a and a metal base upper surface 101a around the glass plug upper surface 103a. The outer peripheral portion of the metal base 101 is connected to the inner peripheral portion of the bottomed cylindrical cap 108 that is connected by resistance welding or the like, filled with the explosive 107, and formed to have an inner peripheral diameter substantially the same as the outer peripheral diameter of the metal base 101. The cap 108 and the metal base 101 are pressed together with the above-mentioned metal base upper surface 101a, the glass plug upper surface 103a and the insulating lead tip surface 104a pressed against the explosive 107 together with the ignition bridge 106. Is sealed by laser welding or the like to form an ignition device (FIG. 4B).

The gunpowder 107 is ignited by energization between the insulating lead 104 and the base lead 105 and the ignition bridge 106 generating heat.
JP 2007-198724 A

  By the way, the ignition bridge 106 on the A surface of the airtight terminal 100 for the ignition device is a thin wire generally formed with a wire diameter of 100 μm or less, and when pressed against the explosive 107, the explosive 107 and the A surface It receives pressure in the middle and causes deformation in the shape along the A surface, and is pressed against the airtight terminal 100 for the ignition device, that is, the A surface.

  Therefore, the A surface of the ignition device hermetic terminal 100 is required to be smooth so as not to damage the ignition bridge 106. For this reason, the surface A of the airtight terminal 100 for the igniter is required to be surfaced by high-precision processing, and there is a problem that the cost is increased although the number of parts is small.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and for an ignition device that can be manufactured at low cost without damaging the ignition bridge and without compromising other functions when assembled as an ignition device. An object is to provide an airtight terminal.

  In order to solve the above-described conventional problems, an airtight terminal for an ignition device according to the present invention has a metal base with a through hole, and is inserted from the through hole and insulated from the base through a sealing glass. An airtight terminal in which the insulated lead is held by a metal base, and the first main surface of the hermetic terminal is formed on the top of the insulating lead around the top of the insulating lead and the first main surface of the metal base around the top of the glass. A portion to be applied is selectively polished, and the entire first main surface of the airtight terminal is smooth.

  With this configuration, it is possible to smooth the entire first main surface of the airtight terminal for the ignition device by selectively polishing a part without polishing the entire first main surface of the airtight terminal, thereby reducing the manufacturing cost. can do.

  As described above, according to the airtight terminal for the ignition device of the present invention, it is possible to reduce the manufacturing cost without impairing the function.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a glass seal as an intermediate product composed of a metal base, a sealing glass, an insulating lead, and a base lead in a manufacturing process of an airtight terminal for an ignition device according to an embodiment of the present invention. The figure (a) is a section showing a metal base, the figure (b) is a section showing a glass sealing object, and the figure (c) is an important section expanded section of a glass sealing object. It is.

  In FIG. 1, 1 is a metal base, 1a is a metal base first main surface, 2 is a through hole, 3 is a sealing glass, 3a is a sealing glass top, 4 is an insulating lead, 4a is an insulating lead top, and 5 is a base. Each lead is shown.

  It is press-molded with a press die and is a trace of shearing processing during press molding around the through-hole 2 of the first main surface 1a of the metal base 1 with the through-hole 2 (R in the figure) Is formed as an annular raised portion (the raised dimension is B in the figure), the insulating lead 4 is inserted into the through hole 2, and the insulating lead 4 is held on the metal base 1 through the sealing glass 3, The metal base 1 and the insulating lead 4 are electrically insulated, and the sealing glass top portion 3a and the insulating lead top portion 4a corresponding to the metal base first main surface 1a are substantially annularly raised on the first main surface 1a. The top of the metal base 1 is formed on the same surface height as the top of the part or at a height slightly higher than the top of the raised part. Base lead 5 is melted on the two main surfaces, for example It is erected at.

  That is, on the metal base first main surface 1a, the height of the base portion formed by the top portion of the annular raised portion of the metal base 1, the sealing glass top portion 3a and the insulating lead top portion 4a on the inside is higher by the B dimension. It is formed. The raised dimension B of the hill part is in the range of 10 to 100 μm, preferably about 15 to 30 μm.

  Here, the burr explained as the above-described annular bulge can be adjusted in the bulge dimension B by adjusting the clearance between the press die and the punch.

  Further, when the swell dimension B is determined more strictly, a two-stage process may be used in which a circular trapezoidal part is formed by extrusion of a press and then a through hole is formed in the central part of the trapezoidal part.

  FIG. 2 shows a completed airtight terminal for an ignition device using such a glass sealing body.

  In FIG. 2, the same components as those in FIG. In FIG. 2, 10 indicates an airtight terminal for the ignition device.

  The airtight terminal 10 for the ignition device shown in FIG. 2 is formed by selectively grinding and polishing the hill portion described in FIG. 1, and is formed of a metal base first main surface 1a, a sealing glass top portion 3a, and an insulating lead top portion 4a. A smooth C-plane is formed.

  According to such a configuration, it is not necessary to grind and polish the entire first main surface of the airtight terminal 10 for the ignition device, and the insulating lead top 4a corresponding to the hill portion of the first main surface of the airtight terminal 10 for the ignition device can be obtained. A smooth surface (C surface in the figure) can be obtained by selectively grinding and polishing only the sealing glass top part 3a and the metal base first main surface 1a around the glass top part 3a (Y part in the figure). Thus, the manufacturing cost can be reduced.

  Such a method for manufacturing the airtight terminal 10 for the ignition device can be referred to FIG.

  A metal base having a through hole, a cylindrical glass tablet, and a lead material are prepared (material preparation step). In the periphery of the through hole of the metal base first main surface, the annular raised portion described in FIG. 1 is provided. The glass tablet is obtained by compression-molding glass powder together with a binder and pre-baking.

  Next, a metal base, a glass tablet, and an insulating lead, which are erected on the second main surface by welding, are assembled into an assembly jig made of carbon, and the glass tablet is inserted into the through hole of the metal base, An insulating lead is inserted into the hole of the tablet (assembly process).

  Here, the top of the annular raised portion on the metal base first main surface is brought into contact with the assembly jig surface, and the glass tablet and the insulating lead located in the through hole of the metal base are also on the jig surface. Keep their tops in contact.

  Next, the assembled jig is heated in a sealing furnace, and the metal base and the insulating lead are sealed with glass (glass sealing step).

  Here, at the time of glass sealing, the top of the annular raised portion, the top of the glass tablet, and the top of the insulating lead on the metal base first main surface are in contact with the assembly jig surface, The molten glass melted by the glass tablet becomes the sealing glass without flowing out to the periphery, and the hill part described with reference to FIG. 1 is formed.

  Next, the hill portion is selectively ground and polished to complete an airtight terminal for an ignition device with a smooth first main surface (partial polishing step).

  Here, in order to reduce the number or size of bubbles contained in the sealing glass, a glass tablet which has been subjected to heat vacuum treatment and degassed may be used for assembly.

  According to this, the number and magnitude | sizes of the recessed part by the bubble which appears on the top part surface of the sealing glass grind-polished can be reduced, and the smoothness of this surface can be improved.

  In addition, using tableted glass is less expensive than using tube glass.

  It is useful as a secret terminal for an ignition device, and is particularly suitable for those requiring smoothness on the main surface.

Sectional drawing of the glass sealing body which is an intermediate product in embodiment of this invention Sectional drawing of the airtight terminal for ignition devices in embodiment of this invention Manufacturing flow diagram of airtight terminal for ignition device in an embodiment of the present invention Sectional drawing which shows the airtight terminal for conventional ignition devices, and an ignition device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 Metal base 1a Metal base 1st main surface 2,102 Through-hole 3 Sealing glass 3a Sealing glass top part 4,104 Insulating lead 4a Insulating lead top part 5,105 Base lead 10,100 Airtight terminal for ignition device 101a Metal Base upper surface 103 Glass stopper 103a Glass stopper upper surface 104a Insulating lead tip surface 106 Ignition bridge 107 Gunpowder 108 Cap

Claims (3)

An airtight terminal having a metal base having a through hole, and an insulating lead inserted through the through hole and insulated from the base through a sealing glass, held by the metal base,
A portion of the first main surface of the hermetic terminal, which is centered on the top portion of the insulating lead, and is applied to the sealing glass top and the first main surface of the metal base around the top of the glass is selectively polished, and the hermetic terminal An airtight terminal for an ignition device, wherein the entire first main surface of the ignition device is smooth. The top part of the annular bulge part around the through hole on the first main surface of the metal base and the assembly jig surface are brought into contact with each other, and the top part of the glass tablet and the insulating lead located in the through hole of the metal base By heating the top part in contact with the jig surface and melting the glass tablet to form a sealing glass, the glass is sealed to form a hill part,
The hill portion is selectively ground and polished to smooth the entire first main surface including the first main surface of the metal base, the top of the sealing glass, and the top of the insulating lead. Manufacturing method of airtight terminal. The method for producing an airtight terminal for an ignition device according to claim 2, wherein the glass tablet is defoamed by heating and vacuuming.