JP2017084954A - Airtight terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an airtight terminal in which airtightness reliability is enhanced while ensuring the mechanical strength of a lead material and a glass sealing part.SOLUTION: An airtight terminal 10 consists of a metal outer ring 11 having at least one through hole, a lead-out lead 12 inserted into the through hole of this metal outer ring 11, and an insulation glass 13 filling the through hole and sealing the metal outer ring and the lead-out lead airtightly. The lead-out lead 12 is obtained by providing a core material 121, composed of a low resistance metal material, with a pipe lead 122 of lower thermal expansion than the core material on the outer periphery of the core material 121 across a gap, and then filling the gap with a soft brazing filler metal 123.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an airtight terminal.

  The hermetic terminal is a lead-sealed lead with an insulating material inserted in the insertion hole of the metal outer ring, supplying current to the electrical equipment and elements housed in the hermetic container, and signals from the electrical equipment and elements. It is used when deriving from the outside. In particular, GTMS (Glass-to-Metal-Seal) type hermetic terminals, in which the metal outer ring and the lead are sealed with insulating glass, are roughly classified into two types, a matching sealing type and a compression sealing type. In order to ensure highly reliable hermetic sealing in the above-described hermetic terminal, it is important to appropriately select the thermal expansion coefficients of the outer ring and the lead metal material and the insulating glass. The insulating glass for sealing is determined by the material of the metal outer ring and the lead, the required temperature profile, and its thermal expansion coefficient. In the case of alignment sealing, the sealing material is selected so that the thermal expansion coefficients of the metal material and the insulating glass match as much as possible. On the other hand, in the compression sealing, a metal material and an insulating glass material having different thermal expansion coefficients are selected intentionally so that the outer metal ring compresses the insulating glass and the lead.

  In order to ensure high hermetic reliability and electrical insulation, the conventional hermetic terminal has a Kovar that has the same thermal expansion coefficient as that of the glass outer ring and lead material in a wide temperature range. An alloy (Fe 54%, Ni 28%, Co 18%) is used, and both are sealed with insulating glass made of borosilicate glass. For compression-sealing type airtight terminals, concentric compressive stress is applied to the glass in the operating temperature range. Steel outer ring made of carbon steel or stainless steel and iron alloy lead material such as iron nickel alloy (Fe50%, Ni50%) and iron chromium alloy (Fe72%, Cr28%) Both were sealed with insulating glass made of soda barium glass.

  In addition, there is a dumet wire as a sealing metal wire used for a soft glass encapsulating portion of a semiconductor device such as an electron tube, a light bulb, a discharge lamp, a diode, or a thermistor. A dumet wire is a composite wire in which an iron / nickel alloy is used as a mandrel and copper is coated thereon, and the surface is further oxidized or borated, and is defined in Japanese Industrial Standards of Non-Patent Document 1. However, the jumet wire has only a relatively thin wire diameter for a bulb tube such as a lamp and cannot cope with an increase in capacity. In addition, a lead base material with a large core wire diameter corresponding to an increase in capacity and a copper plating film applied thereto are caused by the occurrence of gas component leaks from the plating process and poor film adhesion. There is a drawback that it is difficult to wipe out problems such as swelling and peeling, a rough surface structure of deposited metal, and a so-called Dog-Bone phenomenon due to thickening of the edge portion due to the tip current effect.

JP 61-260560 A

Japanese Industrial Standard JIS H 4541-1997 Jumet wire

  In recent years, it has been demanded that airtight terminals be compatible with high power. For example, a compact and high-performance compressor is required for a refrigerator installed in a store with limited space such as a convenience store. In this way, recent compressors, mainly for business use, tend to be smaller than conventional sizes, but the maximum current value that passes through the airtight terminal attached to the compressor naturally increases as the capacity of the refrigerator increases. Tend to. Conventionally, high resistance metals such as iron alloys have been used as lead materials for airtight terminals for refrigerators due to restrictions such as mechanical strength of the leads and pins. For this reason, when an electrical overload is applied, the insulating glass melts due to the Joule heat of the lead material, and airtightness cannot be secured, and in the worst case, there is a risk that the lead material falls off. Particularly for high-power applications, it is more preferable from the viewpoint of efficient use of electric energy, such as response to high power and power saving, if current conduction heat generation of the lead material of the hermetic terminal can be suppressed. It is only necessary to change from conventional iron alloy lead materials to lead materials made of low resistance metals such as copper and aluminum alloys. However, these low resistance materials have lower mechanical strength than iron alloys, and lead / This is inconvenient because the pins are easily bent. Insulating glass used for sealing is generally a low thermal expansion coefficient material. Therefore, if the lead material is a high thermal expansion coefficient material such as silver, copper, aluminum, a silver alloy, a copper alloy, or an aluminum alloy, matched sealing is the principle. It becomes unavailable. Even in compression sealing, low resistance metals have a larger coefficient of thermal expansion than steel materials used for the metal outer ring, and if this is used for the lead material, the lead material shrinks after sealing, so there is a load on the insulating glass. The compressive stress that can be made becomes too small, making it difficult to ensure airtightness. It is conceivable that both the metal outer ring and the lead material are made of a material having a high thermal expansion coefficient such as silver, copper, aluminum or an alloy thereof, but in that case, the compressive stress applied to the insulating glass becomes too large, and the glass of the sealing material It is not possible to adopt because cracks occur.

  Conventionally, airtight terminals using copper core leads have been proposed for the purpose of reducing the electrical resistance of the lead material. As shown in Patent Document 1, there is an airtight terminal using a composite lead material in which the surface of a copper core is coated with an alloy steel. However, since the lead material of the hermetic terminal of Patent Document 1 has a copper inner core surface fixedly coated with an outer jacket made of alloy steel, the lead material of copper is subject to the restriction of mounting the lead in a limited metal outer ring. If the inner core diameter is increased and the outer jacket of the alloy steel is made thinner, the mechanical strength of the lead cannot be maintained and the coating of the alloy steel cannot sufficiently resist the large thermal expansion of the copper, resulting in sufficient compression sealing. I can't get it. Conversely, if the copper diameter of the inner core is reduced and the coating of the alloy steel is increased, there is a structural limit that it becomes difficult to obtain a desired lead resistance value. In addition, when the lead has mechanical strength within a practical range, the outer jacket of the steel material is always energized as a current path, and the outer jacket of the alloy steel has a specific resistance several tens of times that of copper. Therefore, even if heat generation is suppressed in the copper material portion, large heat generation occurs in the steel material portion. If the copper core is made thicker in order to suppress energization to the steel material, the heat generation of the steel material can be suppressed and the thermal stress between the lead and the glass can be reduced, but instead a large amount of heat is generated between the copper material on the energization side and the steel material. Stress is generated and the material interface is easily peeled off. Therefore, in the structure of the steel outer jacket and the copper inner core, the effect of lowering the electrical resistance of the copper core material and the excessive thermal expansion of the copper core material antagonize, so the thermal stress of the copper core material and the coated steel material The problem of interfacial delamination could not be solved, and the composite interface of the metal material was affected by the thermal history, and there was a drawback that the airtightness was easily lost.

  An object of the present invention is, for example, a hermetic terminal suitable for high power use such as a hermetic terminal for a refrigerator, a battery cell such as a secondary battery or a fuel cell, and a high-capacity relay for vehicle use, and includes a lead material and a glass seal. An object of the present invention is to provide a hermetic terminal with improved hermetic reliability while ensuring the mechanical strength of the wearing portion.

  According to the present invention, in an airtight terminal comprising a metal outer ring, a lead lead inserted into the metal outer ring, and an insulating glass that hermetically seals the inner wall of the metal outer ring and the outer diameter of the lead lead, The lead-out lead is characterized in that a core lead made of a low resistance metal material is provided with a pipe lead having a lower thermal expansion than the core material with a gap around the outer periphery of the core material, and the gap is filled with a soft brazing material. An airtight terminal is provided.

  An airtight terminal according to the present invention airtightly connects a metal outer ring having at least one through hole, a lead lead inserted through the through hole of the metal outer ring, and the metal outer ring and lead lead filled in the through hole. The lead wire is made of insulating glass to be sealed, and the lead wire is provided on a core material made of a low resistance metal material with a pipe lead having a lower thermal expansion than the core material with a gap around the outer periphery of the core material. Fill with material. The lead out has a three-layer cross section. The pipe lead of the outermost layer has a rim function that minimizes the thermal expansion of the core material while supporting the core material as the lead lead structure material and maintaining the sealing with the insulating glass. The soft solder material of the intermediate layer joins the core material and the pipe lead, and has spreadability to buffer the stress generated between the core material having a large thermal expansion and the pipe lead having a smaller thermal expansion. The core material may be a metal material having a low electrical resistance, and may have a larger thermal expansion than the two layers described above.

  The hermetic terminal according to the present invention hermetically seals a metal outer ring, a pipe lead of a conductive lead inserted through a through hole formed in the metal outer ring, and the metal outer ring and the pipe lead. Component transfer process for combining insulating glass tablets and setting them in a sealing jig, heating furnace in which the metal outer ring, pipe leads, and insulating glass tablets set in the sealing jig are adjusted to a temperature above the glass softening point Glass sealing process that seals the metal outer ring and pipe lead through the glass, brazing preparation process in which the core material is inserted into the sealed pipe lead and soft brazing material is set and set up in the previous process In the brazing process in which the pipe lead sealed with the outer metal ring, the core material and the soft brazing material are passed through a heating furnace adjusted to a temperature not lower than the melting temperature of the soft brazing material and lower than the glass softening point, and both are brazed. Yo It is manufactured Te. Any method can be used for attaching the soft brazing material to the core material as long as it can be filled with a molten soft solder material between the pipe lead and the core material in the brazing process. A method of attaching a material and inserting it into a sealed pipe lead and passing it through a furnace, or installing a soft brazing material on the end of a pipe lead or core material sealed in a metal outer ring and passing through a furnace Can be suitably used.

  According to the present invention, in the lead-out lead of the hermetic terminal having a high electric capacity, the heat stress between the core material made of the low resistance metal material and the exterior pipe lead is arranged in the intermediate layer between the two, and the soft solder material rich in spreadability. By buffering, the interface peeling at the material interface of the lead out made of a composite material having different electric resistance and thermal expansion is prevented, and airtight reliability is improved. Further, by using a pipe lead made of a low thermal expansion material as the outermost layer, the electrical resistance of the hermetic terminal can be reduced without impairing the mechanical strength of the insulating glass that seals the lead-out lead and the metal outer ring.

  According to the method for manufacturing an airtight terminal according to the present invention, the core material is hermetically brazed to the pipe lead by soft brazing at a temperature much lower than the glass sealing temperature. Reduces shrinkage and suppresses interface peeling between core material and pipe lead.

The top view of the airtight terminal 10 which concerns on this invention is shown. The front view of the airtight terminal 10 which concerns on this invention is shown, and the front fragmentary sectional view cut | disconnected along the DD line | wire of FIG. 1 is shown. The bottom view of the airtight terminal 10 which concerns on this invention is shown. FIG. 20 shows a process flow diagram 20 of an airtight terminal according to the present invention.

  As shown in FIGS. 1 to 3, the hermetic terminal 10 according to the present invention is inserted into a metal outer ring 11 made of iron or an iron alloy having at least one through hole, and the through hole of the metal outer ring 11. The lead 12 and the insulating glass 13 hermetically sealing the metal outer ring 11 and the lead 12 filled in the through hole. The lead 12 is made of silver, copper, aluminum or a silver alloy, copper alloy, aluminum. A pipe lead 122 made of iron having a lower thermal expansion than the core 121 or an iron alloy such as Fe-Ni alloy, Kovar alloy, Fe-Cr alloy, or ferritic stainless steel is provided on the core 121 made of a low-resistance metal such as an alloy. Is provided on the outer periphery of the core 121 with a gap interposed therebetween, and the gap is formed by a single metal such as Sn having a melting temperature of less than 450 ° C., Sn—Bi alloy, or Sn—Bi—Ag alloy. Sn-Cu alloy, Sn-Ag alloy, Sn-Ag-In-Bi alloy, Sn-Ag-Cu alloy, Sn-Cu-Ag alloy, Sn-Cu-Ni alloy, Sn-Zn alloy, Sn-Zn-Bi It is filled with a solder material such as an alloy, a Sn—Zn—Al alloy, or a soft solder material 123 such as an Au—Sn alloy.

  As shown in the process flow diagram 20 of FIG. 4, the hermetic terminal 10 of the present invention includes a metal outer ring, a pipe lead of a conductive lead inserted through a through hole formed in the metal outer ring, a metal outer ring and a pipe. A component transfer step 21 in which an insulating glass tablet that hermetically seals the lead is combined and set in a sealing jig, a metal outer ring set in the sealing jig, a pipe lead, and an insulating glass tablet are softened. A glass sealing step 22 for sealing the metal outer ring and the pipe lead through a heating furnace adjusted to a temperature equal to or higher than the temperature, inserting the core material into the pipe lead after sealing, and attaching a soft soldering material The brazing preparation step 23 for setting, and the pipe lead, the core material, and the soft brazing material, which are glass-sealed to the metal outer ring set up in the previous step, are brought to a temperature higher than the melting temperature of the soft brazing material and lower than the glass softening point of the insulating glass Produced by brazing step 24 of both contact row through a heated was heated furnace. The method of attaching the soft solder material to the core material is to insert the core material with the soft solder material attached to the peripheral wall in advance into the inner diameter of the pipe lead after sealing, or the core material is inserted into the pipe lead sealed with glass, Next, it is preferable to apply a soft soldering material to the end of the pipe lead or the core material and to pass through the furnace. Since the core material is hermetically brazed with the pipe lead by soft brazing at a low temperature of less than 450 ° C, the temperature difference during cooling is small and the rapid contraction in the lead axis direction is alleviated, and the interface material peels off the core material and the pipe lead. To prevent.

  As shown in FIGS. 1 to 3, the hermetic terminal 10 of Example 1 according to the present invention is inserted into a carbon steel outer metal ring 11 having three through holes and a through hole of the outer metal ring 11. The lead 12 is composed of an insulating glass 13 of soda barium glass filled in the through hole and hermetically sealing the metal outer ring 11 and the lead 12, and the lead 12 has a lower heat than copper on the copper core 121. Pipe leads 122 made of expanded Fe—Cr alloy are provided on the outer periphery of the copper core with a gap therebetween, and this gap is filled with a soft solder material 123 of Sn—Cu alloy.

  As shown in the process flow diagram 20 of FIG. 4, the hermetic terminal 10 according to the first embodiment of the present invention includes a metal outer ring, and a pipe lead of a conductive lead inserted in a through hole formed in the metal outer ring, A component transfer step 21 in which an insulating glass tablet is hermetically sealed between the metal outer ring and the pipe lead and set in the sealing jig, and the metal outer ring and pipe lead set in the sealing jig A glass sealing step 22 in which a metal outer ring and a pipe lead are sealed in a glass furnace through a furnace heated to 1000 ° C. above the glass softening point, and a pipe lead sealed in the metal outer ring. A brazing preparation step 23 in which a core material coated with Sn-Cu alloy is inserted into the inner wall of the inner wall of the brazing, and a pipe lead, a core material, and a soft brazing material sealed in a metal outer ring set up in the previous step , A temperature above the melting soft brazing material, is manufactured by brazing step 24 of both contact row through a heating furnace controlled at 300 ° C. lower than the glass softening point of the dielectric glass.

  The present invention can be used for an airtight terminal that is durable to a high voltage and a high current, particularly under a high pressure, and requires high airtightness.

10 ... Airtight terminal,
11 ... Metal outer ring,
12: Derived lead,
13: Insulating glass,
121 ... core material,
122 ... Pipe lead,
123 ... soft brazing material,
20 ... Process flow diagram,
21 ... Parts transfer process,
22 ... Glass sealing step,
23 ... brazing preparation process,
24: Brazing process.

Claims (10)

  Metal outer ring having at least one through hole, lead-out lead inserted into the through-hole of the metal outer ring, and insulating glass filled in the through-hole and hermetically sealing the metal outer ring and the lead-out lead The lead is provided on a core made of a low-resistance metal material with a pipe lead having a lower thermal expansion than that of the core material with a gap around the outer periphery of the core material, and the gap is filled with a soft brazing material. Airtight terminal characterized by   The hermetic terminal according to claim 1, wherein the low-resistance metal material is selected from silver, copper, aluminum, a silver alloy, a copper alloy, and an aluminum alloy.   3. The airtight terminal according to claim 1, wherein the pipe lead is selected from iron or an iron alloy such as an Fe—Ni alloy, a Kovar alloy, an Fe—Cr alloy, or a ferritic stainless steel material.   The hermetic terminal according to any one of claims 1 to 3, wherein the soft solder material is made of a single metal having a melting temperature of less than 450 ° C, a solder material, or a soft solder material.   The soft solder material is Sn, Sn-Bi alloy, Sn-Bi-Ag alloy, Sn-Cu alloy, Sn-Ag alloy, Sn-Ag-In-Bi alloy, Sn-Ag-Cu alloy, Sn-Cu- Any one of claims 1 to 4, wherein the alloy is selected from an Ag alloy, a Sn-Cu-Ni alloy, a Sn-Zn alloy, a Sn-Zn-Bi alloy, a Sn-Zn-Al alloy, and an Au-Sn alloy. The airtight terminal as described in one.   Combining a metal outer ring, a pipe lead of a conductive lead inserted through a through hole formed in the metal outer ring, and an insulating glass tablet that hermetically seals both between the metal outer ring and the pipe lead A component transfer step for setting the sealing jig, and passing the metal outer ring, the pipe lead, and the insulating glass tablet set on the sealing jig through a heating furnace adjusted to a temperature equal to or higher than the glass softening point. In a glass sealing step for sealing the metal outer ring and the pipe lead in a glass, a brazing preparation step for inserting a core material into the pipe lead after sealing and mounting and setting a soft brazing material, in a previous step The pipe lead, the core material, and the soft soldering material that are glass-sealed to the metal outer ring that has been set up are adjusted to a temperature not lower than the melting temperature of the soft soldering material and lower than the glass softening point of the insulating glass. Method for producing a hermetic terminal, characterized in that the assembly by brazing step of the two contact row through a heating furnace.   The method of manufacturing an airtight terminal according to claim 6, wherein the core material is selected from silver, copper, aluminum, a silver alloy, a copper alloy, and an aluminum alloy.   The airtight terminal according to claim 6 or 7, wherein the pipe lead is selected from iron or an iron alloy such as an Fe-Ni alloy, a Kovar alloy, an Fe-Cr alloy, and a ferritic stainless steel material. Production method.   The method of manufacturing an airtight terminal according to any one of claims 6 to 8, wherein the soft solder material is made of a single metal having a melting temperature of less than 450 ° C, a solder material, or a soft solder material. The soft solder material is Sn, Sn-Bi alloy, Sn-Bi-Ag alloy, Sn-Cu alloy, Sn-Ag alloy, Sn-Ag-In-Bi alloy, Sn-Ag-Cu alloy, Sn-Cu- Any one of claims 6 to 9, wherein the alloy is selected from an Ag alloy, a Sn-Cu-Ni alloy, a Sn-Zn alloy, a Sn-Zn-Bi alloy, a Sn-Zn-Al alloy, and an Au-Sn alloy. The manufacturing method of the airtight terminal as described in any one.

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