EP0324627A2 - Glühkerze - Google Patents

Glühkerze Download PDF

Info

Publication number
EP0324627A2
EP0324627A2 EP89300281A EP89300281A EP0324627A2 EP 0324627 A2 EP0324627 A2 EP 0324627A2 EP 89300281 A EP89300281 A EP 89300281A EP 89300281 A EP89300281 A EP 89300281A EP 0324627 A2 EP0324627 A2 EP 0324627A2
Authority
EP
European Patent Office
Prior art keywords
sheath
plug
discontinuity
wall
zone
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.)
Withdrawn
Application number
EP89300281A
Other languages
English (en)
French (fr)
Other versions
EP0324627A3 (de
Inventor
Patrick Christopher O'brien
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.)
WELLMAN AUTOMOTIVE PRODUCTS Ltd
Original Assignee
WELLMAN AUTOMOTIVE PRODUCTS 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 WELLMAN AUTOMOTIVE PRODUCTS Ltd filed Critical WELLMAN AUTOMOTIVE PRODUCTS Ltd
Publication of EP0324627A2 publication Critical patent/EP0324627A2/de
Publication of EP0324627A3 publication Critical patent/EP0324627A3/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23Q—IGNITION; EXTINGUISHING-DEVICES
    • F23Q7/00—Incandescent ignition; Igniters using electrically-produced heat, e.g. lighters for cigarettes; Electrically-heated glowing plugs
    • F23Q7/001—Glowing plugs for internal-combustion engines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B1/00—Engines characterised by fuel-air mixture compression
    • F02B1/02—Engines characterised by fuel-air mixture compression with positive ignition
    • F02B1/04—Engines characterised by fuel-air mixture compression with positive ignition with fuel-air mixture admission into cylinder

Definitions

  • This invention relates to electrically operated glow plugs used as an aid to speedy start-up of internal combustion engines, in particular diesel and other compression ignition engines as used in vehicles.
  • the invention relates to glow plugs of the kind including a housing adapted to mount the plug in the wall of a cylinder or other combustion chamber of the engine in use, a tubular sheath carried by the housing to project into the combustion chamber in use, the distal extremity or tip of the sheath containing a totally enclosed heating element whereby the tip of the sheath speedily attains a high temperature when electric current is applied thereto by way of an electrode carried in the housing, and a resistance element also totally enclosed in the sheath electrically interconnecting the heating element with the electrode and formed of a material having a high positive temperature coefficient of resistance.
  • This kind of glow plug is hereinafter referred to as "a sheathed element self-limiting glow plug”.
  • the object of the present invention is to provide a glow plug of said kind which is economical to manufacture, reliable and durable in use, and which will attain its working temperature very much more quickly than most if not all known plugs of the kind for rapid starting of an engine from cold.
  • a sheathed element self-limiting glow plug characterised in that there is a discontinuity in the wall of the sheath in an intermediate zone at or adjacent to the interconnection between the coils whereby conductive dispersion of heat from the tip portion of the sheath containing the heating element to the remainder thereof is substantially delayed or resisted.
  • the discontinuity is conveniently a substantial reduction in cross sectional area of the sheath in that zone as by a substantial reduction in diameter and/or a substantial reduction in wall thickness in that zone.
  • the discontinuity may also be provided by a gap or gaps in the sheath wall in that zone.
  • Said gap or gaps may be occupied by one or more spacers or distance pieces which may be formed from a material having low heat conductivity and which may be bonded to the adjoining sheath wall portions to provide mechanical strength.
  • the sheath normally serves as the grounded or earth return of the electrical circuit from the distal end of the heating element, if the sheath wall is completely broken by the discontinuity, as when a continuous spacer or distance piece is used which is not electrically conductive an electrical connection bridging the discontinuity e.g. a wire connection, will be provided.
  • the plug comprises a tubular metal housing 10 of conventional shape including an externally screwthreaded portion 12 which will be received in a threaded bore through the wall of an engine combustion chamber in use, its outer end being provided with a hexagon head 14 for engagement by a spanner.
  • An insulated electrode 16 having a connecting terminal 18 at its outer end is sealed into and extends through housing 10 in known manner.
  • a hollow cylindrical metal sheath 20 projects from the inner end of housing 10.
  • the distal extremity or tip portion 22 remote from the body is totally closed and the proximal end part 24 of the sheath is fitted within a bore of the inner end of housing 10 and is closed in sealing engagement with electrode 16 in known manner.
  • a wound wire heating coil 26 is located within tip 22, its distal end being electrically connected, e.g. by welding, to the tip, sheath 20 and housing 10 constituting the earth return side of the electrical circuit.
  • a wound wire resistance coil 28 within sheath 20 has one end electrically connected to electrode 16, e.g. by welding.
  • coil 28 is substantially longer than coil 26 and extends from the part of sheath 20 within housing 10 along the exposed portion of the sheath towards coil 26, it is electrically connected in series with coil 26 by a short axial connecting rod or wire 30 to which the adjacent ends of the coils are welded.
  • sheath 20 is swaged or otherwise formed to provide a reduced diameter neck 32 at an intermediate zone along the length of the sheath in the region of the connecting rod or wire 30, i.e. between the tip portion 22 of the sheath occupied by heating coil 26 and the major proximal part of the sheath occupied by the resistance coil 28.
  • the wall thickness of the sheath is also substantially reduced by the swaging process at said reduced diameter.
  • the discontinuity so formed in the sheath provides a heat stop between the coils due to the much reduced cross sectional area of the metal sheath at said intermediate zone, delaying conductive dispersion of heat from the tip portion 22 back along the sheath to its proximal portion.
  • Heating coil 26 may be made of "Kanthal” alloy and the resistance coil 28 may be made of nickel or nickel alloy.
  • Sheath 20 is filled with electrically insulating material 34 which also helps to keep the coils centered in place, for example magnesium oxide or other inert heat resistant material, in known manner.
  • Sheath 20 is typically formed from a stainless steel.
  • Tip portion 22 may attain full heat in as little as 2 seconds or less enabling extremely fast start-up of the engine from cold. This is little more than the time needed for effective cranking of the engine on start-up.
  • a diesel or other compression ignition engine e.g. in a passenger car may be started as easily and quickly as a petrol engine with electric ignition.
  • the plug described is at least as durable and reliable as those of conventional design; indeed the fast operation may enhance durability in that the plug will normally have to operate for only very brief periods at or near full heat.
  • Figure 2 shows an alternative arrangement in which the discontinuity is a complete break or gap 232 extending right around the sheath wall in the zone of the connection 30 between the coils.
  • the two parts of the sheath are connected by a short bridging wire 240.
  • the insulating material 34 filling the sheath might be fused or bonded to form a body within the sheath which will assist in securing the two parts safely together.
  • said gap might not be continuous, but in two or more parts separated by narrow integral bridging pieces across the gap.
  • Figure 3 shows a further alternative in which the tip portion 22 of the sheath is connected to the remaining portion by a washer or spacer 332 formed of a material having low heat conductivity e.g. a glass or ceramic material sintered or otherwise bonded to the remaining parts of the sheath. If said material is not electrically conducting the discontinuity so formed will again need to be bridged by a wire or the like (not shown) to complete the grounded or earth return.
  • a washer or spacer 332 formed of a material having low heat conductivity e.g. a glass or ceramic material sintered or otherwise bonded to the remaining parts of the sheath.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Resistance Heating (AREA)
EP89300281A 1988-01-14 1989-01-12 Glühkerze Withdrawn EP0324627A3 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8800807 1988-01-14
GB8800807A GB2214568B (en) 1988-01-14 1988-01-14 Glow plug

Publications (2)

Publication Number Publication Date
EP0324627A2 true EP0324627A2 (de) 1989-07-19
EP0324627A3 EP0324627A3 (de) 1990-01-17

Family

ID=10629959

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89300281A Withdrawn EP0324627A3 (de) 1988-01-14 1989-01-12 Glühkerze

Country Status (2)

Country Link
EP (1) EP0324627A3 (de)
GB (1) GB2214568B (de)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1279896A1 (de) * 2001-07-23 2003-01-29 Beru AG Glühkerzen und Verfahren zu deren Herstellung
WO2010003727A1 (de) * 2008-07-11 2010-01-14 Robert Bosch Gmbh Glührohr, insbesondere für eine glühstiftkerze
JP2011145062A (ja) * 2007-04-27 2011-07-28 Man Diesel Se ガスエンジンのための点火装置及びガスエンジン
JP2015152222A (ja) * 2014-02-14 2015-08-24 日本特殊陶業株式会社 グロープラグ

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2058216A (en) * 1979-09-01 1981-04-08 Bosch Gmbh Robert Glow plug for internal combustion engines
FR2490888A1 (fr) * 1980-09-20 1982-03-26 Bosch Gmbh Robert Bougie d'allumage a pointe incandescente pour moteurs a combustion interne
JPS61105028A (ja) * 1984-10-26 1986-05-23 Mitsubishi Electric Corp デイ−ゼルエンジン用グロ−プラグ

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2058216A (en) * 1979-09-01 1981-04-08 Bosch Gmbh Robert Glow plug for internal combustion engines
FR2490888A1 (fr) * 1980-09-20 1982-03-26 Bosch Gmbh Robert Bougie d'allumage a pointe incandescente pour moteurs a combustion interne
JPS61105028A (ja) * 1984-10-26 1986-05-23 Mitsubishi Electric Corp デイ−ゼルエンジン用グロ−プラグ

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 10, no. 286 (M-521)(2342) 27 September 1986, & JP-A-61 105028 (MITSUBISHI) 23 May 1986 *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1279896A1 (de) * 2001-07-23 2003-01-29 Beru AG Glühkerzen und Verfahren zu deren Herstellung
US6753505B2 (en) 2001-07-23 2004-06-22 Beru Ag Glow plugs and a method of producing glow plugs
JP2011145062A (ja) * 2007-04-27 2011-07-28 Man Diesel Se ガスエンジンのための点火装置及びガスエンジン
WO2010003727A1 (de) * 2008-07-11 2010-01-14 Robert Bosch Gmbh Glührohr, insbesondere für eine glühstiftkerze
US20110180525A1 (en) * 2008-07-11 2011-07-28 Patrick Vedel Glow tube, in particular for a sheathed-element glow plug
JP2015152222A (ja) * 2014-02-14 2015-08-24 日本特殊陶業株式会社 グロープラグ

Also Published As

Publication number Publication date
GB2214568B (en) 1991-08-21
GB8800807D0 (en) 1988-02-17
GB2214568A (en) 1989-09-06
EP0324627A3 (de) 1990-01-17

Similar Documents

Publication Publication Date Title
US5589091A (en) Glow plug with prestressed contact surfaces
CA1089307A (en) Glow-plug
EP0229677A2 (de) Glühkerze
KR100427818B1 (ko) 세라믹히터
US4112577A (en) Method of making electric heater
US6878903B2 (en) Glow plug
JPS60114629A (ja) デイ−ゼルエンジン用グロ−プラグ
US4252091A (en) Glow plug construction
US5039839A (en) Diesel engine glow plug with self-temperature saturation characteristic and extended after-glow-time
US4661686A (en) Dual line ceramic glow plug
US5132516A (en) Glow plug having self-temperature control function
EP1471307B1 (de) Glühkerze
US5206483A (en) Temperature controlled glow plug having controlled saturation and afterglow characteristics
US5251589A (en) Hot tip glow plug and method for making
US5468933A (en) Rod flame glow plug having a CoFe alloy regulating coil and a housing having a fuel connection for a metering device
EP0324627A2 (de) Glühkerze
EP0989370A2 (de) Metallspitze für Glühsensor
JP2002526737A (ja) セラミック製のシース形グロープラグ
EP0365258A1 (de) Glühkerze
US4592134A (en) Glow plug
EP0989367B1 (de) Keramische Spitze für Glühsensor
US4237843A (en) Starting aid for a combustion engine
JP3754529B2 (ja) 自己制御型セラミックヒータ
GB2216952A (en) Glow plugs
JPS6350606Y2 (de)

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

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE CH DE ES FR GR IT LI LU NL SE

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH DE ES FR GR IT LI LU NL SE

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

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19900718