WO2002037028A1 - Bougie luisante de type rechauffeur ceramique et procede de fabrication de la bougie luisante - Google Patents

Bougie luisante de type rechauffeur ceramique et procede de fabrication de la bougie luisante Download PDF

Info

Publication number
WO2002037028A1
WO2002037028A1 PCT/JP2001/009507 JP0109507W WO0237028A1 WO 2002037028 A1 WO2002037028 A1 WO 2002037028A1 JP 0109507 W JP0109507 W JP 0109507W WO 0237028 A1 WO0237028 A1 WO 0237028A1
Authority
WO
WIPO (PCT)
Prior art keywords
outer cylinder
ceramic heater
metal outer
ceramic
glow plug
Prior art date
Application number
PCT/JP2001/009507
Other languages
English (en)
Japanese (ja)
Inventor
Arihito Tanaka
Takashi Aota
Jian Zhao
Toshitsugu Miura
Original Assignee
Bosch Automotive Systems Corporation
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
Priority claimed from JP2000337955A external-priority patent/JP3589176B2/ja
Priority claimed from JP2000337954A external-priority patent/JP2002147758A/ja
Application filed by Bosch Automotive Systems Corporation filed Critical Bosch Automotive Systems Corporation
Publication of WO2002037028A1 publication Critical patent/WO2002037028A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/10—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor
    • H05B3/12—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor characterised by the composition or nature of the conductive material
    • H05B3/14—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor characterised by the composition or nature of the conductive material the material being non-metallic
    • H05B3/141—Conductive ceramics, e.g. metal oxides, metal carbides, barium titanate, ferrites, zirconia, vitrous compounds
    • 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
    • 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
    • F23Q2007/004—Manufacturing or assembling methods
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B2203/00—Aspects relating to Ohmic resistive heating covered by group H05B3/00
    • H05B2203/027—Heaters specially adapted for glow plug igniters

Definitions

  • the present invention relates to a glow plug used for assisting the start of a diesel engine, and more particularly to a glow plug of a ceramic glow using a glow plug as a heat generating means.
  • Heating elements such as coils of high melting point metal (for example, tungsten) or conductive ceramics are embedded in the insulating ceramics, or a part of the heating element made of conductive ceramics is exposed.
  • a ceramic heater formed by compounding with an inorganic conductor as a material is fixed in a metal outer cylinder by brazing, and a lead wire on the negative electrode side of the heating element is taken out from a side surface of the insulating ceramic to form a metal.
  • the lead wire on the positive electrode side was connected to one end of an electrode extraction bracket on the end face opposite to the position where the heating element of insulating ceramic was embedded, and A ceramic heater type global plug configured to connect an external connection terminal to the other end of the electrode take-out is conventionally known.
  • a ceramic heater type plug is a type in which a ceramic heater is inserted into a metal outer cylinder, and a heat generating portion on a tip end side of the ceramic heater where the heating element is held is moved from a tip of the metal outer cylinder.
  • the outer peripheral surface of the ceramic tube and the inner peripheral surface of the metal outer cylinder are fixed by brazing (usually silver brazing) with the ceramic outer cylinder protruding outward.
  • the end (rear end) farther from the heat generating part is pressed into or inserted into the internal hole of the housing and fixed by brazing or the like.
  • the ceramic plug may gradually enter the inside of the metal outer cylinder, causing a “entrance phenomenon”. is there.
  • This phenomenon of ceramic heater penetration is considered to occur for the following reasons.
  • the housing of the glow plug is fixed to the cylinder head of the engine, but this cylinder head is water-cooled and is kept at about 100 ° C.
  • the tip of the ceramic heater which is the heat-generating portion of the glow plug, is heated to a temperature of about 140 (TC) due to heat generation. It is exposed to a high temperature of about C.
  • the rear end side of the metal outer cylinder (housing fixed side) has a temperature of approximately 100 ° C, so this ceramic heater and metal outer cylinder assembly As a result, a large temperature gradient occurs in the axial direction as a whole.
  • a silver brazing material (B Ag-8, etc.) is usually used, and its liquidus temperature is about 780 ° C. Therefore, when heat is generated, if the above-described temperature gradient occurs between the ceramic heater and the metal outer cylinder, the brazing portion of the two ends at the tip side of the metal outer cylinder (on the heating section side of the ceramic heater). The temperature is close to the melting point of the silver brazing material of about ° C, and the brazing material at that part becomes soft and tends to fluidize. On the other hand, the temperature of the brazing part near the housing is low and the brazing material remains solid.
  • stainless steel (SUS430, etc.) is generally used as the material for the metal outer cylinder, and its linear expansion coefficient is 10.4 E-6 deg.
  • the coefficient of linear expansion of silicon nitride, which is a general material, is 3.2 E-6 / deg, which is three times or more. Therefore, at high temperatures, the metal outer cylinder expands considerably more than the ceramic heater (particularly, expands in the axial direction), and a relative displacement in the axial direction occurs between the metal outer cylinder and the ceramic heater.
  • the glow plug when the glow plug generates heat, a large temperature gradient is generated at the brazing portion between the ceramic heater and the metal outer cylinder, and the temperature at the tip end near the heating portion of the ceramic heater is high. A large relative displacement occurs in the axial direction between the ceramic heater and the metal outer cylinder, and the brazing material at that location has a tendency to fluidize as described above. On the other hand, the temperature at the rear end near the housing is low, the relative axial displacement between the metal outer cylinder and the ceramic heater is small, and the brazing material at that portion remains solid.
  • this state means that the ceramic heater enters the inside of the metal outer cylinder.
  • the metal outer cylinder starts to contract.
  • the brazing material solidifies as the temperature decreases, and as the metal outer cylinder shrinks, a force is generated to draw in the ceramic material. In other words, when the heat is generated, a force is generated to maintain the state in which the ceramic heater enters the metal outer cylinder.
  • the temperature at the rear (housing side) of the brazing portion between the ceramic heater and the metal outer cylinder was low as described above, and the relative displacement between the ceramic heater and the metal outer cylinder was also reduced by the brazing material. Since no fluidization has occurred, a force that attempts to maintain the original state, that is, a force that opposes the force generated at the distal end portion, is generated. If the force is smaller than the force generated at the distal end side, ceramic ceramic The phenomenon of overnight entry will occur. Conversely, if the force is large, no penetration phenomenon occurs.
  • a ceramic heater and a metal outer shell are used in a state in which the front end of the ceramic mixer has a stepped shape with a large diameter, and this step is in contact with the front end surface of the metal outer cylinder. It describes a configuration in which the tube is fixed by brazing.
  • the configuration described in the former publication when a slip occurs between the ceramic heater and the metal outer cylinder, stress concentrates on the processed portion (the concave portion) of the ceramic heater and a crack is generated. There is a possibility that the structure is complicated, the processing cost is high, and practical use is difficult. Further, the configuration described in the latter publication has a problem that processing is difficult and the cost is high since the ceramic heater is stepped. Therefore, in the past, it was generally practiced to secure the safety factor of the joint by making the length of the joint between the ceramic heater and the metal outer cylinder by silver brazing sufficiently long. However, increasing the length of the joint between the ceramic heater and the metal outer cylinder inevitably increases the length of the ceramic heater, and also increases the amount of silver brazing material used. However, the overall cost was raised.
  • the present invention has been made to solve the above-described problems, and it is possible to reduce the length of ceramic ceramic and reduce the length of the joint between the ceramic heater and the metal outer cylinder.
  • An object of the present invention is to provide a ceramic heater-type global plug that can suppress the phenomenon of entering into an outer cylinder and reduce costs.
  • a ceramic heater type glow plug is a ceramic heater formed of insulating ceramics and an inorganic conductor, and is fitted to the outer periphery of the ceramic husk and joined by brazing.
  • the front end of the ceramic heating element on the heating element side projects outward from the front end of the metal outer cylinder.
  • the end is located inside the metal outer cylinder, and the length of the metal outer cylinder protruding from the end of the fixing portion to the housing is L, and the length of the metal outer cylinder is inside the metal outer cylinder of the ceramic heater.
  • the ceramic heater type glow plug according to the invention even if the length of the joining portion between the metal outer cylinder and the ceramic heater is shortened, the phenomenon of the ceramic heater entering can be prevented, and the brazing required for the joining portion can be prevented. Material can be saved and costs can be reduced. In addition, the length of the ceramic heater can be shortened, and the cost can be easily reduced. Furthermore, as in the conventional configuration, it is necessary to perform additional processing of ceramic heaters to prevent the phenomenon of intrusion. Since the stress acting on the part is reduced, it is easy to prevent damage as a whole.
  • the ceramic heater type glow plug according to the invention described in claim 2 is characterized in that the insertion length A of the ceramic heater into the metal outer cylinder satisfies the condition of A> 5 mm. It is.
  • a ceramic heater type glow plug according to the invention as set forth in claim 3 is a ceramic heater formed of insulating ceramics and an inorganic conductor, and is fitted to the outer periphery of the ceramic heater and brazed.
  • the rear end is located inside the metal outer cylinder, and the rear of the metal outer cylinder is slightly behind the portion where the rear end of the ceramic heater is located from the outside. It is characterized by being plastically deformed.
  • the ceramic heater type glow plug according to the third aspect of the present invention, a simple process is performed on the metal outer cylinder without performing additional processing on the ceramic heater, and at a low cost, It is possible to prevent the "entrance phenomenon" in which the ceramics enters the metal outer cylinder.
  • the invention according to claim 4 is characterized in that the rear portion of the metal outer cylinder is slightly crimped rearward from a portion where a rear end portion of the ceramic heater is located. Is what you do.
  • the invention according to claim 5 is characterized in that the metal outer cylinder is shrunken on the entire rear side of a portion where the rear end of the ceramic housing is located.
  • the invention according to claim 6 is characterized in that a protrusion is formed on a rear end surface of the ceramic heater.
  • the invention according to claim 7 is characterized in that a small-diameter portion is formed at the tip end side of the ceramic heater, and an inward bent portion is formed at the tip of the metal outer cylinder. It is characterized in that it is brought into contact with a step between the small diameter portion of the ceramic mix and the rear side thereof.
  • the ceramic heater prevents the phenomenon of entering the metal outer cylinder, and the ceramics heater moves to the distal end side of the metal outer cylinder. It can also be prevented from falling off.
  • An invention of a manufacturing method according to claim 8 is a method for manufacturing the ceramic heater type glow plug, wherein the ceramic heater and the metal outer cylinder are joined by brazing, However, the rear part of the ceramic heater is slightly caulked from the outside to the rear part thereof.
  • the manufacturing method according to claim 9, further comprising: forming a small-diameter portion on a tip portion side of the ceramic heater; and forming an inward bent portion at a tip of the metal outer cylinder. After inserting the small-diameter portion from the rear end of the metal outer cylinder and bringing the step between the small-diameter portion of the ceramic heater and the rear side into contact with the bent portion, the ceramic heater and metal It is characterized by being joined to an outer cylinder by brazing.
  • the rear side of the portion where the rear end portion is located is press-fitted into a housing having an inner hole having a smaller diameter than the outer diameter of the metal outer cylinder, thereby reducing the rear side of the metal outer cylinder.
  • the metal outer cylinder is fixed in the housing.
  • the ceramic heater type glow plug having the above configuration can be manufactured by a simple process at a low cost.
  • FIG. 1 is a vertical cross-sectional view of a ceramic heater-type glow plug according to an embodiment of the present invention.
  • FIG. 2 is an enlarged longitudinal sectional view showing a main part of the ceramics-type glow plug.
  • FIG. 3 is a view for explaining a step of joining the ceramic heater of the ceramic heater type glow plug and a metal outer cylinder by brazing.
  • FIG. 4 is a table showing the results of confirmation test 1.
  • FIG. 5 is a table showing the results of confirmation test 2.
  • FIG. 6 is a table showing the results of confirmation test 3.
  • FIG. 7 is a longitudinal sectional view of a ceramic heater type glow plug according to a second embodiment.
  • FIG. 8 is a longitudinal sectional view of a main part of a ceramic heater type glow plug according to a third embodiment.
  • FIG. 9 is a longitudinal sectional view of a main part of a ceramics heater type glow plug according to a fourth embodiment.
  • FIG. 10 is a longitudinal sectional view of a main part of a ceramic heater type glow plug according to a fifth embodiment.
  • FIG. 11 is a longitudinal sectional view of a ceramics-type glow plug according to a sixth embodiment.
  • FIG. 12 is a longitudinal sectional view of a ceramic heater type glow plug according to a seventh embodiment.
  • FIG. 1 is a longitudinal sectional view of a ceramic heater type glow plug (indicated by the reference numeral 1) according to an embodiment of the present invention
  • FIG. 2 is an enlarged view of a main part thereof.
  • the housing 2 of the glow plug 1 is substantially cylindrical, and has a stepped axial hole 4 formed therein.
  • the central portion 4b of the internal hole 4 of the housing 2 has a small diameter, and a ceramic heater to be described later is fixed to the left side of the small diameter portion 4b.
  • the inner diameter is slightly larger than the small diameter portion 4b.
  • a middle diameter portion 4a is formed.
  • the opening 4e located to the left of the middle diameter portion 4a for fixing the ceramic heater has a slightly larger inner diameter than the ceramic heater fixing portion (medium diameter portion) 4a.
  • the right side of the figure for fixing the external connection terminal and the insulating member, which will be described later, is a large diameter portion 4c.
  • a rear portion 8 of a metal outer cylinder 8 to which a ceramic heater 6 is joined by brazing (silver brazing).
  • the d side is press-fitted or inserted and fixed by brazing or the like. Therefore, the opening 4 e closer to the distal end than the middle diameter portion 4 a has a gap without contacting the outer surface of the metal outer cylinder 8.
  • a heating wire (heat generating material) 64 made of a high melting point metal (for example, tungsten (W) or the like) in a coil shape is embedded in a ceramic insulator 62 constituting a main body thereof. It has a heat generating portion 6a, and the heat generating portion 6a projects outside from the tip 8b of the metal outer cylinder 8, and the rear side of the heat generating portion 6a is inserted into the metal outer cylinder 8.
  • the end face 6 b is located inside the metal outer cylinder 8.
  • the heating element 6a is made of a high melting point metal.
  • the ceramic heater 6 may be composed of an insulating ceramic and an inorganic conductor as a heating element.
  • the heating element may be a conductive ceramic or a sheet-like heating element. A part of the heating element of the conductive ceramic is exposed from the insulating ceramic. What is necessary is just to be formed by compounding.
  • a negative lead wire 66 is connected to one end 64 a of the coiled heating wire 64 embedded in the ceramic heater 6, and a positive lead wire is connected to the other end 64 b. 6 8 are connected.
  • the lead wire 66 on the negative electrode side is exposed on the outer surface of the ceramic insulator 62 inside the metal outer cylinder 8 and is electrically connected to the inner surface of the metal outer cylinder 8 by brazing.
  • the end 68 a of the lead wire 68 on the positive electrode side extends to the rear end face 6 b side of the ceramic heater 6, and one end 12 a of the electrode extraction bracket 12 inside the ceramic heater 6. It is connected to the.
  • FIG. 3 (a) shows a process of joining the ceramic ceramics 6 and the metal outer cylinder 8, and the positive electrode lead wire 68 of the ceramics heater 6 and the electrode extraction metal fitting 12 by silver brazing. This will be described with reference to (b) and (c).
  • the ceramic heater 6 is inserted into the metal outer cylinder 8, and the metal outer cylinder 8 and the ceramic heater 6 are mounted in a brazing jig 14 for positioning.
  • the heat generating portion 6a at the tip of the ceramic heater 6 protrudes outside from the tip 8b of the metal outer cylinder 8, and the electrode extraction fitting 1 2
  • the opposite end 6 d to which is connected is located inside the metal outer cylinder 8.
  • the surface of the ceramic heater 6 where silver brazing is to be performed (the outer peripheral surface thereof and the inner peripheral surface of the electrode mounting bracket mounting hole 6c) are formed by surface treatment such as forming a nickel metal (Ni) layer. It is carried out.
  • Ni nickel metal
  • a metallizing process that is, a process of baking at a temperature of about 950 ° C. to convert a metal component (nickel) in the paste into a metal film is performed.
  • the electrode is formed in the electrode extraction fitting mounting hole 6 c formed at the rear end 6 d of the ceramic heater 6 and exposing the side surface of the end 68 a of the positive lead wire 68. Insert one end 1 2a of bracket 1 2.
  • a linear silver brazing material 26 is wound into a coil having an outer diameter approximately equal to the inner diameter of the metal outer cylinder 8 and inserted into the metal outer cylinder 8 to form a ceramic. Place it on the end face 6b of the heater 6 (see Fig. 3 (a)).
  • the silver opening material 26 is melted (see FIG. 3 (b)), and the outer peripheral surface of the ceramic heater 6 and the metal outer cylinder 8 are heated.
  • Between the inner surface of the electrode and the inner surface of the mounting hole 6c formed at the end 6d of the ceramics 6 and the outer surface of the electrode take-out fitting 12 and brazing is performed. (See Fig. 3 (c)).
  • an insulating member (insulating bush) 20 integrally fixed to the outer peripheral surface of the external connection terminal 18 is provided in the large-diameter portion 4 c (right side in FIG. 1) of the internal hole 4 of the housing 2. It is inserted and fixed. Irregularities such as twill knurls are formed on the outer periphery of the external connection terminal 18, and an insulating bush 20 made of an insulating resin is fixed.
  • the insulating bush 20 is connected to the large-diameter portion 4 of the internal hole 4. c and fixed by caulking the end 2 a of the housing 2.
  • the external connection terminal 18 has an axial through-hole 18 a penetrating the shaft core portion.
  • One end 12 a of the through-hole 18 a is connected to the positive electrode side lead wire of the ceramic heater 6.
  • the electrode extraction bracket (electrode extraction wire) 12 connected to 8 is passed through, and the other end 1 2b is brazed or crimped to the external end surface 18b (the right end in Fig. 1).
  • a washer-shaped insulating member 22 is fitted on the outer side of the crimped end 2 a of the housing 2, and an aluminum nut 24 is attached to the tightening screw 18 c of the external connection terminal 18.
  • each member such as the metal outer cylinder 8 and the housing 2, the relative position between each member 2, 6, and 8, the material of these members and the linear expansion coefficient, etc. Further, a test was conducted on the fixing method between the respective members and the like in order to confirm the limit conditions when the phenomenon of the ceramic heater 6 entering the metal outer cylinder 8 occurs and when the phenomenon does not occur.
  • the protruding length L of the metal outer cylinder 8 from the housing 2 is considered to be related to all the items (a to d) of the factors presumed to be the cause of the above-described phenomenon of entry.
  • the length of the ceramic heater 6 inserted into the metal outer cylinder 8 (see A in the figure). This is the brazing length between the ceramic shell 6 and the metal outer cylinder 8.
  • This brazing length is also considered to be related to all of the estimation factors (a to d).
  • Outer diameter of ceramic heater 6 ((i) d).
  • the inner and outer diameters of the metal outer cylinder 8 and the ceramic heater 6 are considered to be related to the estimated factors a, c, and d.
  • Heating part (heater part) of ceramic heater 6 Distance between 6a and brazing part A, that is, the length of ceramic heater 6 protruding from metal outer cylinder 8 (see T in the figure).
  • the length T of the protruding portion of the ceramic heater 6 is considered to be related to all of the above estimation factors (a to d).
  • This gap is a portion where the brazing material flows during the brazing process and joins the both 6, 8 and is considered to be related to the estimated factors (:, d).
  • the material and the linear expansion coefficient of the metal outer cylinder 8, the ceramic heater 6, and the brazing material are related to the estimated factors c and d.
  • the fixed portion between the metal outer cylinder 8 and the housing 2 is related to the estimated factors a, c, and d.
  • each of the members 2, 6, and 8 constituting the ceramic heater-type glow plug 1 affect the above-mentioned estimated factors, and the case where “entrance phenomenon” occurs and does not occur It is thought that there is. Therefore, endurance tests were carried out using test samples in which the size, material, etc. of each of these members were changed in various ways, including those using actual vehicles, to confirm the boundary conditions between when "entrance phenomenon” occurs and when it does not occur. did.
  • the ceramic heater 6 is a silicon nitride ceramic and has a linear expansion coefficient of 3.2 E-6 Z deg.
  • the metal outer cylinder 8 is made of SUS430 (ferrite) and has a linear expansion coefficient of 10.4. E-6 / deg and a nickel heat-resistant alloy containing about 70% nickel (Ni) with a linear expansion coefficient of 13.3 E-6 / deg were used. Further, as the brazing material, silver brazing material BAg-8 was used.
  • the length L of the metal outer cylinder 8 protruding from the housing 2 is 1 Omm and 2 Om m, and the insertion length A of the ceramic shell 6 into the metal outer cylinder 8 is 3 mm. , 5 mm, 7.5 mm, 10 mm, 12.5 mm, 15 mm, 20 mm, and 25 mm were used.
  • D is ⁇ 4.0 mm and 5.0 mm, and the outer diameter of ceramic heater 6 ⁇ d is ⁇ 3.0 mm and 3.5 mm. Were used.
  • the protrusion length T of the ceramic heater 6 from the metal outer cylinder 8 was set to two types of 7. Omm and 9. Omm.
  • the length B of the fixed portion of the metal outer cylinder 8 to the housing 2 was set to 1 Omm and 2 Omm.
  • the metal outer cylinder 8 was fixed to the housing 2 by two methods: press-fitting and brazing.
  • the gap between the metal outer cylinder 8 and the ceramic heater 6 is generally 50/2 to 1 on one side.
  • this sample is set to 75 on one side. Further, the temperature of the ceramic heater 6 is adjusted so that the temperature of the portion of the outer periphery of the metal outer cylinder 8 where the tip 8b of the metal outer cylinder 8 is located (see C in the figure) becomes 700 ° C. Set the temperature of. In this test sample, the temperature at the point C was set by setting the tip temperature of the ceramic ceramic 6 to 1400 ° C to 1500 ° C, and the liquidus temperature of the silver brazing material (BAg-8) 700 ° C, which is close to 780 ° C).
  • the ceramic heater-type glow plug 1 assembled with the various members as the sample was fixed to a jig (block) corresponding to a cylinder head with screws, and current was supplied under the following conditions. I do.
  • the energizing conditions are:
  • the temperature of the ceramic heater 6 is 1400 ° C or 1500 ° (: The temperature of the ceramic heater 6 where the tip 8b of the metal outer cylinder 8 is located is 700 ° C, and the housing is The temperature of 2 will be about 100 ° C. When it is OFF for 30 seconds, the temperature of the tip of ceramic heater 6 will be about 100 ° C, and the temperature of housing 2 will be about 100 ° C. Blow air to cool.
  • Confirmation test 1 was performed under the above test conditions.
  • the energization conditions were as follows: the temperature of the tip of the ceramic heater 6 was 1500 ° C (the temperature at point C was 700 C), and the applied voltage was 12.5 ports.
  • the material of the metal outer cylinder 8 was SUS430, and the test was performed while changing L and A.
  • Figure 4 shows the results of confirmation test 1.
  • L-A fixing of the metal outer cylinder 8
  • Axial phenomena occur only when the end 4 f and the rear end face 6 b of the ceramic heater 6 are -2.5 mm and 15 mm (document numbers 5, 6, 13, 14). , 21, 29).
  • L-A is any other value, no penetration phenomenon has occurred.
  • the penetration phenomenon does not occur, however, the distance between the metal outer cylinder 8 and the ceramic heater 6 is increased. Insufficient airtightness (Document Nos. 1, 9, 17, 25).
  • the method of fixing the metal outer cylinder 8 to the housing 2 is press-fitting, the material of the metal outer cylinder 8 SUS 430 and nickel heat-resistant alloy, L was fixed to 10 mm, and the test was performed while changing the value of A. I went.
  • Figure 5 shows the results of confirmation test 2.
  • the protrusion length T of the ceramic heater 6 was shortened, and the outer diameter * D of the metal outer cylinder 8 and the outer diameter ⁇ d of the ceramic heater 6 were made smaller than in the confirmation test 1.
  • the material is SUS430
  • the penetration phenomenon occurs only when the L-A is -2.5mm and 15mm, as in the results of the confirmation test 1 above (Document Nos. 5 and 6).
  • the test results did not change, and the phenomenon that L-A penetrated only when -2.5 mm and -1.5 mm was observed. Has occurred (Document Nos. 13 and 14).
  • the insertion length A of the ceramic heater 6 into the metal outer cylinder 8 was 3 mm, the airtightness between the metal outer cylinder 8 and the ceramic heater 6 became poor (Document Nos. 1, 9). ).
  • the test consisted of a mileage of 25,000 km, a running period of 13 months, a running area in a city, and a total of 3,500 times of power supply to the gross plug.
  • Figure 6 shows the results of confirmation test 3. Also in this test, the penetration phenomenon occurred only when L-A was -5.0 mm (Document No. 3). The results of this test are also consistent with the above confirmation tests.
  • the occurrence of the penetration phenomenon is limited to L-A (the axial positional relationship between the fixed end 4 f of the metal outer cylinder 8 and the rear end face 6 b of the ceramic heater 6). And other conditions, such as the radial dimensions (ci) D and ⁇ d) of the metal outer cylinder 8 and the ceramic shell 6, and the protrusion of the metal outer cylinder 8 from the housing 2. It is not affected by the length L. Then, the phenomenon of intrusion occurs only in the range of 15 mm and L-A ⁇ 0, and does not occur in the range of L-A ⁇ -5 mm or 0 ⁇ LA.
  • the metal outer cylinder 8 is fixed to the housing 2 by press-fitting or brazing does not affect the penetration phenomenon. Further, the material of the metal outer cylinder 8 does not affect the penetration phenomenon as long as it is within the above-mentioned conditions (SUS430, nickel heat-resistant alloy). On the other hand, when A ⁇ 5 mm, the airtightness between the metal outer cylinder 8 and the ceramic heater 6 after the confirmation test was poor. In conclusion, the axial distance (L—A) between the fixed end 4 f of the metal outer cylinder 8 to the housing 2 and the rear end face 6 b of the ceramic heater 6 located in the metal outer cylinder 8.
  • the temperature does not rise under the influence of the housing 2 (about 100 ° C). Therefore, when the distal end portion 6a of the ceramic heater 6 is heated to a high temperature, the metal outer cylinder 8 protrudes, and even if a retraction force of the ceramic heater 6 is generated during cooling, the retraction force is smaller than the retraction force. However, since the opposing force on the rear end side is larger, it is considered that no entering phenomenon occurs.
  • the rear end 6 d of the ceramic heater 6 is slightly inserted into the fixing portion 8 d of the metal outer cylinder 8 to the housing 2.
  • the rear end 6 d of the ceramic heater 6 that has entered does not rise in temperature due to the low temperature (about 100 ° C) of the housing 2 even when the glow plug 1 is heated, but this range is extremely large. It is slight. Therefore, when the front end 6a of the ceramic heater 6 is heated to a high temperature, the metal outer cylinder 8 protrudes, and thereafter, when the drawing force of the ceramic heater 6 is generated during cooling, the penetration generated at the rear end side. Since the opposing force is smaller than the retracting force, a penetrating phenomenon occurs.
  • the ceramic heater 6 is inserted into the metal outer cylinder 8.
  • the occurrence of the entry phenomenon can be suppressed.
  • the rear end portion 6d of the ceramic heater 6 is not inserted at all into the portion 8d fixed in the housing 2 of the metal outer cylinder 8, so that the ceramic heater 6 Is shortened.
  • the rear end 6 d of the ceramic heater 6 has a length exceeding 5 mm in the fixing portion 8 d of the metal outer cylinder 8 to the housing 2.
  • the metal outer cylinder 8 and the ceramic heater 6 have a smaller heat capacity than the housing 2 ⁇ cylinder head (not shown), the metal outer cylinder 8 and the ceramic heater In the evening 6, the metal outer cylinder 8 becomes hot without being affected by the housing 2 and the cylinder head up to the vicinity of the fixed end 4 f of the metal outer cylinder 8 to the housing 2, and enters the housing 2 from near the fixed end 4 f. The temperature drops sharply under the influence of the housing 2 cylinder head along the opening of the housing.
  • the brazing material is softened and tends to flow, so that the metal outer cylinder 8 is protruded due to a difference in linear expansion coefficient between the metal outer cylinder 8 and the ceramic heater 6. There is not much resistance to this. Also, during cooling, the tip end protruding from the fixed end to the housing 2 is not affected by the housing 2 ⁇ cylinder head, so the temperature rises more rapidly than near the fixed part side of the housing 2. The degree does not decrease. Therefore, the distal end side of the metal outer cylinder 8 protruding from the fixed end to the housing 2 does not affect the entry phenomenon.
  • the length of the brazing portion between the metal outer cylinder 8 and the ceramic heater 6 also inevitably becomes longer.
  • the resistance to the relative displacement between the metal outer cylinder 8 and the ceramic heater 6 should be greater, and the resistance to the force with which the metal outer cylinder 8 pulls in the ceramic heater 6 during cooling should be greater than when it is short. .
  • the brazing portion on the tip end portion protruding from the housing 2 does not become very resistant because the temperature is slowly lowered during cooling, and the length is long, so that the metal brazing portion is not used.
  • the relative displacement of the tip of the cylinder 8 with respect to the ceramic heater 6 increases.
  • the force for pulling the ceramic heater 6 during cooling increases.
  • the above-mentioned opposing force opposes this pulling-in force, even if the brazing length is long, it does not affect the penetrating phenomenon. From the above, it is considered that the penetration phenomenon of the ceramic heater 6 is influenced only by the vicinity of the fixed end of the housing of the metal outer cylinder 8, and the length of the tip is less affected than that.
  • FIG. 7 is a view showing a ceramic heater type glow plug 1 according to a second embodiment. Since the basic configuration is the same as that of the first embodiment, the same parts are the same. The description is omitted by attaching the reference numerals.
  • the rear end of the ceramic heater 6 of the metal outer cylinder 8 Part 6d is located Slightly rearward from the outside (right side in Fig. 7) from the outside and project inward (the caulked portion is indicated by reference numeral 8c).
  • the rear portion 8 d side of the metal outer cylinder 8 is press-fitted into the cylindrical housing 2 serving as a mounting bracket for the cylinder head. Or insert and fix by brazing.
  • the tip of the heating section 6a of the ceramic heater 6 is projected outward from the tip 8b of the metal outer cylinder 8, and the rear end 6d of the ceramic heater 6 is connected to the metal outer cylinder. Since the structure is located inside the outer casing 8, the ceramic heater 6 can be prevented from moving toward the inside of the outer casing 8 only by crimping the outer casing 8 as described above.
  • the outer peripheral portion of the metal outer cylinder 8 may be swaged all around, or a plurality of portions may be partially swaged. Also, the portion that protrudes inward may not necessarily be a position that directly contacts the rear end face 6 b of the ceramic heater 6. For example, even if the ceramic heater 6 is slightly apart, after the ceramic heater 6 has entered that much, further entry can be regulated.
  • the ceramic heater 6 can be mechanically constrained to prevent the penetration phenomenon without any additional processing of the ceramic heater 6 which is difficult and costly, which is required in the conventional configuration. Further, since the ceramic heater 6 is mechanically constrained, the burden of holding force due to the attachment is reduced, and even when the metal outer cylinder 8 is exposed to a higher temperature, the phenomenon of the ceramic heater 6 getting in is prevented. It does not occur. Furthermore, since the caulked portion 8c presses the end face 6b of the ceramic heater 6, the ceramic heater 6 will not be damaged even if a force acting on the ceramic heater 6 acts.
  • FIG. 8 is an enlarged longitudinal sectional view showing a main part of a ceramic heater type glow plug 1 according to a third embodiment, and is different from the second embodiment only in the shape of the ceramic heater 6.
  • the other parts are the same, so the same parts Are denoted by the same reference numerals, and description thereof is omitted.
  • the rear end face 6ba located inside the metal outer cylinder 8 of the ceramic heater 6 is formed in a spherical shape.
  • the spherical end face 6ba is formed by, for example, grinding the ceramic insulator 62 by hot pressing.
  • the configuration of this embodiment can also provide the same effects as the first embodiment. Further, since the rear end surface 6ba of the ceramic heater 6 has a spherical shape, there is no danger of damaging the rear end portion 6d of the ceramic heater 6 during caulking.
  • FIG. 9 shows a main part of a ceramic heater type glow plug 1 according to a fourth embodiment, in which a rear end face 6bb located in a metal outer cylinder 8 of a ceramic heater 6 has: It has a shape protruding like a taper. Also in the case of this embodiment, when caulking is performed, the rear end portion 6 d of the ceramic heater 6 is formed in the same manner as in the second embodiment in which the rear end surface 6 ba has a spherical shape. Can be prevented from being damaged.
  • FIG. 10 is a view showing a main part of a ceramics heater type glow plug 1 according to a fifth embodiment.
  • a small-diameter portion 6e is formed, and a rear portion 6f has a stepped shape having substantially the same thickness as the inner diameter of the metal outer cylinder 8.
  • the metal outer cylinder 8 has a tip 8 ba bent inward, and the bent end 8 ba is formed between the small diameter portion 6 e of the ceramic ceramic 6 and the large diameter rear portion 6 f. It is in contact with the step between them.
  • the rear side of the metal outer cylinder 8 slightly behind the rear end face 6b of the ceramic heater 6 is caulked from the outer surface and protrudes toward the inner surface (a caulked portion is indicated by 8c).
  • the end 8 d of the metal outer cylinder 8 having a bent portion 8 ba formed by bending the tip in advance is opposite to the bent portion 8 ba.
  • the small diameter portion 6 e of the ceramic heater 6 From the side (upper side in FIG. 4), insert the small diameter portion 6 e of the ceramic heater 6, and insert the step between the small diameter portion 6 e of the ceramic heater 6 and the rear large diameter portion 6 f into the metal
  • the outer cylinder 8 is brought into contact with the inner surface of the bent portion 8 ba.
  • the ceramic heater 6 and the metal outer cylinder 8 are joined by brazing, and the outer surface of the metal outer cylinder 8 after the ceramic heater 6 is joined.
  • the outer surface slightly behind the end face 6 b is swaged.
  • the ceramic heater 6 moves to the tip 8 ba side of the metal outer cylinder 8 in a manner opposite to the above-described intrusion phenomenon. Even when an attempt is made to apply a force, the movement of the ceramic heater 6 can be restricted, and the ceramic heater 6 can be prevented from falling off.
  • the rear end face 6b of the ceramic heat sink 6 located inside the metal outer cylinder 8 is formed into a spherical shape similarly to the third and fourth embodiments (see FIG. 8). Alternatively, it may be made to project in a taper shape (see FIG. 9). This can prevent the rear end 6 d of the ceramic heater 6 from being damaged during caulking.
  • FIG. 11 is a longitudinal sectional view showing the entire structure of a ceramic heater type glow plug 1 according to a sixth embodiment.
  • the configuration of the ceramic heater 6 is the same as that of the second embodiment, except that the metal outer cylinder 8 is located rearward of the rear end 6 d side end face 6 b of the ceramic heater 6.
  • Portion 8d has a smaller overall diameter.
  • a small-diameter rear portion 8 d of the metal outer cylinder 8 is press-fitted and fixed in a middle-diameter portion 4 a of the internal hole 4 of the housing 2.
  • the rear portion 8 d of the metal outer cylinder 8 fixed to the internal hole 4 of the housing 2 has a diameter or press-fit portion substantially the same as the middle diameter portion 4 a of the internal hole 4 of the housing 2.
  • the rear portion 8d is inserted into the internal hole 4a of the housing 2 and is fixed by brazing or press-fitting.
  • the inside diameter of the portion (the middle diameter portion 4a) of the inner hole 4 of the housing 2 to which the metal outer cylinder 8 is fixed is slightly smaller than that in the case of normal press-fitting.
  • a tapered stepped portion 4e is formed between the outer side (the left side in FIG. 11).
  • the rear part 8 d of the metal outer cylinder 8 is attached to the housing 2. It is press-fitted into the inner hole 4 having the above shape. Press the metal outer cylinder 8 into the housing 2 until the portion where the rear end face 6 b of the ceramic heater 6 is located hits the tapered stepped portion 4 e of the housing 2. Fix to 2. By press-fitting into the inner hole 4 of the housing 2 as described above, the entire portion 8 d of the metal outer cylinder 8 behind the end face 6 b of the ceramic heater 6 is reduced in diameter, and the ceramic mixer 6 is accommodated.
  • a step is formed between the portion having the diameter and the reduced diameter portion 8d behind the portion. Therefore, even if the ceramic heater 6 is forced into the metal outer cylinder 8 by the heating and cooling of the glow plug, the end surface 6 b of the ceramic heater 6 remains in the tapered stepped portion 4 of the housing 2. e and are not restrained by the stepped portion of the metal outer cylinder 8 that is reduced in diameter. Also in the sixth embodiment, the same effects as in the above embodiments can be obtained.
  • FIG. 12 is a vertical cross-sectional view of a ceramics glove lug according to a seventh embodiment.
  • the ceramics globe lug 6 is inserted into the metal outer cylinder 8.
  • the electrode take-out fitting 1 2 is inserted into the mounting hole 6 c formed in the rear end 6 d of the ceramic heater 6, and the ceramics heater 6 is joined to the metal outer cylinder 8 by brazing, and the electrode take-out fitting 1 is attached. 2 is connected to 6
  • heat-resistant insulating powder 15 (for example, MgO) is filled into the metal outer cylinder 8 from the end of the metal outer cylinder 8, and an elastic seal member 16 is attached to the end of the metal outer cylinder 8.
  • the metal outer cylinder 8 is swaged on a portion 8 d on the rear side (the right side in FIG. 12) of the portion where the rear end 6 d of the ceramic heater 6 is located.
  • the outer diameter of the portion 8 d is reduced so as to be smaller than the outer diameter of the portion where the ceramic ceramic 6 is located.
  • the swaging portion 8 d is press-fitted into the internal hole 4 of the housing 2 and fixed. Or insert and fix by brazing or the like.
  • the penetration phenomenon of the ceramic heater 6 can be prevented, and the connection between the electrode extraction fitting 12 and the ceramic heater 6 is held by the heat-resistant insulating powder 15, so that vibration For example, the connection can be prevented from being cut or damaged.
  • the configuration of this embodiment may be used together with the caulking of the second embodiment and the like.
  • the swaged portion 8c of the metal outer cylinder 8 is located inside the housing 2, but the swaged portion 8c is located outside the housing 2. You may do it. By doing so, the outer circumference of the metal outer cylinder 8 is swaged. This can be performed after the metal outer cylinder 8 is inserted and fixed in the housing 2. Further, in the configuration of the second to sixth embodiments, the metal outer cylinder 8 may be filled with the heat-resistant insulating powder 15. In any case, the configuration of the present invention is not limited to the illustrated shape or the like, and the ceramic heater 6 is deformed by plastic working of the metal outer cylinder 8 from the outside so that the metal outer cylinder 8 Anything that can be prevented from moving inside can be used.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Resistance Heating (AREA)

Abstract

L"invention concerne une bougie luisante de type réchauffeur céramique pouvant empêcher le soi-disant phénomène d"intrusion, c"est-à-dire un événement tel qu"un réchauffeur céramique (6) devient un tube métallique extérieur (8) par chauffage et refroidissement répétés de la bougie luisante. La partie de pointe latérale de l"élément chauffant (6a) du réchauffeur céramique (6) prolonge la partie de pointe (8b) du tube métallique extérieur (8) et sa partie d"extrémité arrière (6d) est placée à l"intérieur du tube métallique extérieur (8). Dans cette configuration, le réchauffeur céramique (6) est fixé au tube métallique extérieur (8) par brasage tendre à l"argent. La partie d"extrémité arrière du tube métallique extérieur (8) est insérée et fixee dans un boîtier (2) et, lorsqu"une longueur saillante du tube métallique extérieur (8), entre une extrémité fixe (4f) et le boîtier (2), est (L) et que la longueur du réchauffeur céramique (6) insérée dans le tube métallique extérieur (8) est (A), les conditions (L-A<-5 mm ou 0<L-A) sont satisfaites, et la longueur (A) du réchauffeur céramique (6) insérée dans le tube métallique extérieur (8) est (A > 5 mm).
PCT/JP2001/009507 2000-11-06 2001-10-30 Bougie luisante de type rechauffeur ceramique et procede de fabrication de la bougie luisante WO2002037028A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2000337955A JP3589176B2 (ja) 2000-11-06 2000-11-06 セラミックヒータ型グロープラグ
JP2000-337954 2000-11-06
JP2000337954A JP2002147758A (ja) 2000-11-06 2000-11-06 セラミックヒータ型グロープラグおよびその製造方法
JP2000-337955 2000-11-06

Publications (1)

Publication Number Publication Date
WO2002037028A1 true WO2002037028A1 (fr) 2002-05-10

Family

ID=26603475

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2001/009507 WO2002037028A1 (fr) 2000-11-06 2001-10-30 Bougie luisante de type rechauffeur ceramique et procede de fabrication de la bougie luisante

Country Status (1)

Country Link
WO (1) WO2002037028A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60165681U (ja) * 1984-04-12 1985-11-02 日本特殊陶業株式会社 二線式セラミツクグロ−プラグ
JPS6446520A (en) * 1987-08-12 1989-02-21 Nippon Denso Co Resistance device for preheating plug of diesel engine
JPH05332241A (ja) * 1992-06-02 1993-12-14 Nippondenso Co Ltd セラミックグロープラグの通電発熱装置
JPH06168773A (ja) * 1992-11-30 1994-06-14 Kyocera Corp セラミックヒーター

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60165681U (ja) * 1984-04-12 1985-11-02 日本特殊陶業株式会社 二線式セラミツクグロ−プラグ
JPS6446520A (en) * 1987-08-12 1989-02-21 Nippon Denso Co Resistance device for preheating plug of diesel engine
JPH05332241A (ja) * 1992-06-02 1993-12-14 Nippondenso Co Ltd セラミックグロープラグの通電発熱装置
JPH06168773A (ja) * 1992-11-30 1994-06-14 Kyocera Corp セラミックヒーター

Similar Documents

Publication Publication Date Title
EP1262717B1 (fr) Dispositif de chauffage et son procédé de fabrication
JPWO2005080877A1 (ja) グロープラグ
JP2000356343A (ja) セラミックヒータ型グロープラグ
EP1283394B1 (fr) Elément chauffant
WO2015163112A1 (fr) Procédé de fabrication de bougie de préchauffage du type à élément chauffant en céramique et bougie de préchauffage du type à élément chauffant en céramique
JP2002195559A (ja) セラミックスヒータ型グロープラグおよびその製造方法。
JP2001141238A (ja) ディーゼルエンジン用グロープラグおよびその製造方法
JP5302183B2 (ja) グロープラグ及びその製造方法
JP4632565B2 (ja) セラミックヒーター装置及びその製造方法
JP2003185137A (ja) ディーゼルエンジン用グロープラグおよびその製造方法
JP3737880B2 (ja) グロープラグ
WO2005061962A1 (fr) Bougie d&#39;allumage pour systeme de chauffage en ceramique
JP5352296B2 (ja) シースヒータ及びグロープラグ並びにシースヒータの製造方法
WO2002037028A1 (fr) Bougie luisante de type rechauffeur ceramique et procede de fabrication de la bougie luisante
JP3589176B2 (ja) セラミックヒータ型グロープラグ
JP3737879B2 (ja) グロープラグ
JP2004132688A (ja) グロープラグ
JP4309757B2 (ja) セラミックヒーター
JP3873444B2 (ja) グロープラグ及びその製造方法
JP4310565B2 (ja) セラミックヒータ型グロープラグおよびその製造方法
JP3754529B2 (ja) 自己制御型セラミックヒータ
JP3551015B2 (ja) グロープラグ
JP4295164B2 (ja) グロープラグ
JP3664093B2 (ja) セラミックスヒータ型グロープラグ
JP2002147758A (ja) セラミックヒータ型グロープラグおよびその製造方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase