EP0054374A2 - Zündkerzenelektrode und Verfahren zu ihrer Herstellung - Google Patents

Zündkerzenelektrode und Verfahren zu ihrer Herstellung Download PDF

Info

Publication number
EP0054374A2
EP0054374A2 EP81305642A EP81305642A EP0054374A2 EP 0054374 A2 EP0054374 A2 EP 0054374A2 EP 81305642 A EP81305642 A EP 81305642A EP 81305642 A EP81305642 A EP 81305642A EP 0054374 A2 EP0054374 A2 EP 0054374A2
Authority
EP
European Patent Office
Prior art keywords
metal
billet
shaped
cup
spark plug
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP81305642A
Other languages
English (en)
French (fr)
Other versions
EP0054374B1 (de
EP0054374A3 (en
Inventor
Kenneth Howard
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
FLOFORM LIMITED
Original Assignee
FLOFORM Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by FLOFORM Ltd filed Critical FLOFORM Ltd
Publication of EP0054374A2 publication Critical patent/EP0054374A2/de
Publication of EP0054374A3 publication Critical patent/EP0054374A3/en
Application granted granted Critical
Publication of EP0054374B1 publication Critical patent/EP0054374B1/de
Expired legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C23/00—Extruding metal; Impact extrusion
    • B21C23/22—Making metal-coated products; Making products from two or more metals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T13/00—Sparking plugs
    • H01T13/20—Sparking plugs characterised by features of the electrodes or insulation
    • H01T13/39—Selection of materials for electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T21/00—Apparatus or processes specially adapted for the manufacture or maintenance of spark gaps or sparking plugs
    • H01T21/02—Apparatus or processes specially adapted for the manufacture or maintenance of spark gaps or sparking plugs of sparking plugs

Definitions

  • This invention relates to a method of making a spark plug centre electrode having an inner core of a metal which has good thermal conductivity relative to the metal of an outer sheath fully enclosing the inner core, the outer sheath being formed of a corrosion resistant material.
  • a spark plug electrode in which an inner core of a metal having good thermal conductivity, for example copper, is partly encased within a sheath of a metal having good corrosion resistance properties, such as for example nickel or a nickel alloy.
  • a metal having good corrosion resistance properties such as for example nickel or a nickel alloy.
  • the purpose of using a composite electrode of this type is that, while good heat conduction is required of the electrode in order to prevent undue "burning", it is also necessary to provide for a hard-wearing portion of the electrode at and around the point where sparking occurs.
  • the advantage of a composite electrode as described is that a material suitable for good heat conduction is used in conjunction with a material having suitably hard-wearing properties.
  • British Patent 754,591 discloses a method of making a spark plug electrode in which a billet of copper is placed on top of a billet of nickel, the composite billet then being extruded through a suitable die to form a spark plug electrode having at one end a core of metal having good thermal conductivity surrounded by a sleeve of the corrosion resistant metal.
  • a further object of the invention is to provide a centre electrode for a spark plug which can be easily formed at one end to provide a shoulder for mounting in the body of a spark plug.
  • a centre electrode for a spark plug of the type having a core of a first metal within a sheath of a second metal, the first metal having a thermal conductivity higher than that of the second metal and a melting point lower than that of the second metal, the second metal being resistive to the corrosive environment in which the electrode works, characterised by the steps of inserting a billet of the first metal within a cup-shaped billet of the second metal; heating the two billets together to a temperature at or above the melting point of the first metal but below the melting point of the second metal; cooling the two metals to a temperature below the melting point of the first metal to form a composite billet wherein the first and second metals are united at their interfaces and extruding the composite billet so as to form an elongate rod-shaped extrusion comprising a core of the first metal enclosed substantially entirely within a sheath of the second metal.
  • the heating of the first and second metals may conveniently take place in a reducing atmosphere within a radiant furnace, the cup-shaped billet of the second metal being held in a suitably shaped black body so that conduction of heat from the radiant furnace occurs through the black body in order to melt the billet of said first contained within the cup-shaped billet of the second metal.
  • the melting of the billet of said first metal may be just sufficient to wet the interfaces thereof with the cup-shaped second metal or the whole of the first metal may be melted but, in any event, the first and second metals become united at their interfaces to form a unitary composite billet after cooling.
  • the extrusion of the composite billet can occur with a single blow to form an elongate rod-shaped extrusion having a core of the first metal enclosed substantially entirely within a sheath of the second metal, the side-wall of which is generally thicker in the regions above the end of the copper core than in the region adjacent to this core to provide a suitable volume of the nickel alloy at one end for forming a shoulder thereon.
  • the composite extrusion may be cropped off at one end and the shoulder formed at that end in order to provide mounting means for mounting in the ceramic insulator of a spark plug.
  • the composite electrode may conveniently be welded to a wire connector by electric butt welding in a known manner, or may be friction welded.
  • the invention also provides a centre electrode for a spark plug of the type having a core of a first metal within a sheath of a second metal, the first metal having a thermal conductivity higher than that of the second metal and a melting point lower than that of the second metal, the second metal being resistive to the corrosive environment in which the electrode works, whenever produced by the method described in any of the preceding four paragraphs.
  • a cup shaped billet 10 of a heat resistant nickel alloy is of substantially cylindrical shape and has a cylindrical cavity 11 in which has been inserted a copper billet 12, the copper billet having been cropped-off from a length of copper wire (not shown).
  • the cup-shaped billet 10 has a frusto-conical portion 13 at one end thereof comprised solely of nickel alloy.
  • Figure 2 is shown a part-sectional view of a rectangular black body 14 of carbon, having a plurality of apertures 15 of cross-sectional shape corresponding substantially to the cross-sectional shape of billet 10.
  • the copper billet 12 is shown contained within a cup-shaped billet 10.
  • the copper billet 12 has been melted within the cylindrical part 11 of cup-shaped billet 10 by conduction of heat from a radiant furnace (not shown).
  • the meniscus 16 is of concave section, the peripheral edge of which is joined to the inner surface of billet 10.
  • the cup-shaped billet 10 is shown contained within an extrusion die 17 having a cylindrical section 18 of internal diameter corresponding substantially to the external diameter of the billet 10.
  • a converging portion 19 corresponds substantially to the frusto-conical portion of billet 10.
  • An extrusion punch 20 having a frusto-. conical end 21 is capable of axial movement downwardly in order to extrude the billet 10 containing the melted copper billet 12 through an extrusion nozzle 22 provided with a clearance 23 of cylindrical shape.
  • Figure 5 is shown the extruded billet having an inner core 12 of copper and an outer sheath 10 of nickel alloy substantially entirely enclosing the inner core 12.
  • a flanged head 24 comprised solely of the nickel alloy is formed at one end of the extruded billet 10 which meets at junction 25 to substantially enclose the core 12.
  • the other end of the extruded billet 10 is comprised solely of the nickel alloy, the nickel alloy of this end corresponding generally to the nickel alloy contained within the frusto-conical portion 19 of the billet 10 prior to extrusion.
  • the cup-shaped billet 10 containing the copper billet 12 is placed within a correspondingly shaped recess in the black body 14, which is of carbon, and heated in a radiant furnace having a reducing atmosphere to a temperature at or above the melting point of the copper billet so as to cause melting of the copper billet 12 within the cup-shaped billet 10 to form a composite billet as shown in Figure 3.
  • the composite billet 10, 12 is then placed in the extrusion press as shown in Figure 4 and. extruded, by pressure exerted on the billet via punch 20, through nozzle 22 to the shape of a composite electrode as shown in Figure 5.
  • this composite electrode consists of a cigar-shaped inner core 12 of copper and an outer sheath 10 of nickel alloy which substantially entirely encloses the inner core 12 by virtue of part of the metal of cup-shaped billet 10 meeting at 25 subsequent to extrusion.
  • the flanged portion 24 is cropped-off by a cropping machine and a shoulder portion 26 is then formed on this cropped-off end of the billet 10, the shoulder 26 being comprised solely of the nickel alloy.
  • a wire element 27 can then be butt welded to the electrode in any known manner, for example by electric butt welding or friction welding to form a welded junction at 28.
  • a centre electrode is provided according to the invention having closely controlled thermal characteristics which can be simply manufactured and yet is suitable for connection with a wire element as described above.
  • electrodes of different lengths and with different amounts of copper core can be produced by appropriate variations in the volume of copper placed in the cup; and the ratio of cross section of the copper and nickel alloy composite is determined by the ratio of cylindrical bore to outside diameter of the nickel alloy cup shaped billet.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Spark Plugs (AREA)
EP81305642A 1980-12-10 1981-11-27 Zündkerzenelektrode und Verfahren zu ihrer Herstellung Expired EP0054374B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8039567A GB2088753B (en) 1980-12-10 1980-12-10 Spark plug electrode
GB8039567 1980-12-10

Publications (3)

Publication Number Publication Date
EP0054374A2 true EP0054374A2 (de) 1982-06-23
EP0054374A3 EP0054374A3 (en) 1982-07-21
EP0054374B1 EP0054374B1 (de) 1985-03-13

Family

ID=10517887

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81305642A Expired EP0054374B1 (de) 1980-12-10 1981-11-27 Zündkerzenelektrode und Verfahren zu ihrer Herstellung

Country Status (7)

Country Link
EP (1) EP0054374B1 (de)
AU (1) AU551102B2 (de)
CA (1) CA1203510A (de)
DE (1) DE3169299D1 (de)
GB (1) GB2088753B (de)
NZ (1) NZ199163A (de)
ZA (1) ZA818375B (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2172223A (en) * 1985-03-11 1986-09-17 Champion Spark Plug Co Composite center electrode for a spark plug and method for producing same
CN108270149A (zh) * 2016-12-30 2018-07-10 宁波卓然铱金科技有限公司 火花塞中心电极制造镍杯-铜芯合成机构

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB754591A (en) * 1953-06-06 1956-08-08 Bosch Gmbh Robert A method for the extrusion of rod-shaped or pin-shaped metal articles, particularly sparking plug electrodes
DE2238283A1 (de) * 1972-04-14 1973-10-25 Nippon Denso Co Verfahren zur herstellung von zuendkerzenmittelelektroden
DE2755120A1 (de) * 1977-12-10 1979-06-13 Atomic Energy Authority Uk Verfahren zur herstellung einer zuendkerzenelektrode
GB2024665A (en) * 1978-07-07 1980-01-16 Ford Motor Co Spark plug electrode manufacture
DE1941979B2 (de) * 1968-09-03 1980-04-10 Champion Spark Plug Co., Toledo, Ohio (V.St.A.) Zündkerze
GB2037190A (en) * 1978-12-16 1980-07-09 Gkn Floform Ltd Manufacture of spark plug electrode

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB754591A (en) * 1953-06-06 1956-08-08 Bosch Gmbh Robert A method for the extrusion of rod-shaped or pin-shaped metal articles, particularly sparking plug electrodes
DE1941979B2 (de) * 1968-09-03 1980-04-10 Champion Spark Plug Co., Toledo, Ohio (V.St.A.) Zündkerze
DE2238283A1 (de) * 1972-04-14 1973-10-25 Nippon Denso Co Verfahren zur herstellung von zuendkerzenmittelelektroden
DE2755120A1 (de) * 1977-12-10 1979-06-13 Atomic Energy Authority Uk Verfahren zur herstellung einer zuendkerzenelektrode
GB2024665A (en) * 1978-07-07 1980-01-16 Ford Motor Co Spark plug electrode manufacture
GB2037190A (en) * 1978-12-16 1980-07-09 Gkn Floform Ltd Manufacture of spark plug electrode

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2172223A (en) * 1985-03-11 1986-09-17 Champion Spark Plug Co Composite center electrode for a spark plug and method for producing same
CN108270149A (zh) * 2016-12-30 2018-07-10 宁波卓然铱金科技有限公司 火花塞中心电极制造镍杯-铜芯合成机构

Also Published As

Publication number Publication date
DE3169299D1 (en) 1985-04-18
AU7813781A (en) 1982-06-17
GB2088753A (en) 1982-06-16
CA1203510A (en) 1986-04-22
GB2088753B (en) 1984-02-01
AU551102B2 (en) 1986-04-17
EP0054374B1 (de) 1985-03-13
EP0054374A3 (en) 1982-07-21
ZA818375B (en) 1982-11-24
NZ199163A (en) 1984-09-28

Similar Documents

Publication Publication Date Title
US4635851A (en) Casting nozzle
US4644140A (en) Electric heating arrangement for spray nozzles
US4590669A (en) Method of preparing resistance thermometer
US2955222A (en) Center electrode structure for spark plugs and process for making the same
US4684352A (en) Method for producing a composite spark plug center electrode
DE10112781B4 (de) Verfahren zum Herstellen einer Glühkerze
JPH0325336B2 (de)
KR20000070947A (ko) 납땜 인두팁 및 그 제조 방법
CN1024876C (zh) 火花塞电极及其制造工艺
US3144576A (en) Spark plug and method of manufacture
US4314392A (en) Method of making a spark plug electrode
US4695759A (en) Method for producing a composite center electrode and an electrode
EP0054374B1 (de) Zündkerzenelektrode und Verfahren zu ihrer Herstellung
US4720697A (en) Terminal for electrical resistance heating element and a method for the manufacture of such terminals
US4410309A (en) Method of making a spark-plug center electrode
CA1268020A (en) Method for producing a composite center electrode for spark plug
EP0637863A1 (de) Zündkerzenelektroden
US2162062A (en) Manufacture of spark plugs
US4155776A (en) Electrical heat sensing element, and method of its manufacture, particularly for gas burning appliances
US3077649A (en) Process of envelopment
JP2717682B2 (ja) スパークプラグの中心電極の製造方法
GB2037190A (en) Manufacture of spark plug electrode
US2890070A (en) Rail-bond shoe attachable by conically pointed brazing pin
GB2036608A (en) Method of manufacturing centre electrodes for spark plugs
JP2633655B2 (ja) 良熱伝導金属が包み込まれたスパークプラグの外側電極製造方法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Designated state(s): BE DE FR GB IT

AK Designated contracting states

Designated state(s): BE DE FR GB IT

17P Request for examination filed

Effective date: 19821207

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: FLOFORM LIMITED

ITF It: translation for a ep patent filed

Owner name: SOCIETA' ITALIANA BREVETTI S.P.A.

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): BE DE FR GB IT

REF Corresponds to:

Ref document number: 3169299

Country of ref document: DE

Date of ref document: 19850418

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
GBPC Gb: european patent ceased through non-payment of renewal fee
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19881118

ITTA It: last paid annual fee
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20001113

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20001122

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 20001218

Year of fee payment: 20

BE20 Be: patent expired

Free format text: 20011127 *FLOFORM LTD