JPH0565714B2 - - Google Patents
Info
- Publication number
- JPH0565714B2 JPH0565714B2 JP22191786A JP22191786A JPH0565714B2 JP H0565714 B2 JPH0565714 B2 JP H0565714B2 JP 22191786 A JP22191786 A JP 22191786A JP 22191786 A JP22191786 A JP 22191786A JP H0565714 B2 JPH0565714 B2 JP H0565714B2
- Authority
- JP
- Japan
- Prior art keywords
- structure according
- injection nozzle
- metal member
- nozzle structure
- tip
- 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.)
- Expired - Lifetime
Links
- 239000002184 metal Substances 0.000 claims description 27
- 238000002347 injection Methods 0.000 claims description 20
- 239000007924 injection Substances 0.000 claims description 20
- 239000000919 ceramic Substances 0.000 claims description 14
- 238000003466 welding Methods 0.000 claims description 8
- 239000007769 metal material Substances 0.000 claims description 5
- 229910001347 Stellite Inorganic materials 0.000 claims description 4
- AHICWQREWHDHHF-UHFFFAOYSA-N chromium;cobalt;iron;manganese;methane;molybdenum;nickel;silicon;tungsten Chemical compound C.[Si].[Cr].[Mn].[Fe].[Co].[Ni].[Mo].[W] AHICWQREWHDHHF-UHFFFAOYSA-N 0.000 claims description 4
- 238000005260 corrosion Methods 0.000 claims description 4
- 230000007797 corrosion Effects 0.000 claims description 4
- 238000005219 brazing Methods 0.000 claims description 2
- 238000009792 diffusion process Methods 0.000 claims description 2
- 229910001293 incoloy Inorganic materials 0.000 claims description 2
- 229910000833 kovar Inorganic materials 0.000 claims description 2
- 238000005482 strain hardening Methods 0.000 claims description 2
- 239000000463 material Substances 0.000 claims 3
- 239000010410 layer Substances 0.000 description 10
- 239000000446 fuel Substances 0.000 description 7
- 239000002344 surface layer Substances 0.000 description 4
- 238000002485 combustion reaction Methods 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- 229910000521 B alloy Inorganic materials 0.000 description 1
- 229910001339 C alloy Inorganic materials 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 239000000567 combustion gas Substances 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000005304 joining Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000007751 thermal spraying Methods 0.000 description 1
Landscapes
- Fuel-Injection Apparatus (AREA)
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明は燃料を霧化して内燃機関へ供給する噴
射ノズルに係り、特にノズル本体を金属でノズル
先端部をセラミツクスで形成した噴射ノズル構造
に関する。Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an injection nozzle that atomizes fuel and supplies it to an internal combustion engine, and particularly relates to an injection nozzle structure in which the nozzle body is made of metal and the nozzle tip is made of ceramics. .
［従来の技術］
内燃機関の燃焼室にノズル先端部を臨ませて配
設される噴射ノズルは、常時燃焼ガスに曝される
ため高温強度が要求される。このため本出願人は
特開昭58−14316号公報に少なくともノズルボデ
イの先端となる噴口部をSi3N4またはAl2O3等の
セラミツクスで形成したエンジン用燃料噴射ノズ
ルを提案している。[Prior Art] An injection nozzle disposed with its nozzle tip facing the combustion chamber of an internal combustion engine is required to have high-temperature strength because it is constantly exposed to combustion gas. For this reason, the present applicant has proposed a fuel injection nozzle for an engine in JP-A-58-14316, in which at least the nozzle portion, which is the tip of the nozzle body, is formed of ceramics such as Si 3 N 4 or Al 2 O 3 .
［発明が解決しようとする問題点］
セラミツクスは金属材料に比べて熱膨張係数
が小さい、大きな耐熱衝撃性をもつ、熱伝導
度が小さいなどの優れた長所をもつ。[Problems to be Solved by the Invention] Ceramics has superior advantages compared to metal materials, such as a lower coefficient of thermal expansion, greater thermal shock resistance, and lower thermal conductivity.
しかし噴口部をセラミツクス、ノズル本体を金
属で形成し、これらを一体に接続する技術につい
ては構造、コスト上で改善の余地を残していた。 However, the technique of forming the nozzle part from ceramics and the nozzle body from metal, and connecting them together, left room for improvement in terms of structure and cost.
［問題点を解決するための手段］
本発明は上記問題点を解決することを目的とし
ている。本発明は針弁を昇降自在に収容するノズ
ル本体とセラミツクスから形成されて噴口を有す
るノズル先端部とをリング状の中間金属部材を介
して一体に接続し、この中間金属部材に上記針弁
が着座されるシート部を形成して噴射ノズル構造
を成すものである。[Means for Solving the Problems] The present invention aims to solve the above problems. The present invention connects a nozzle body that accommodates a needle valve so as to be freely raised and lowered, and a nozzle tip made of ceramics and having a spout through a ring-shaped intermediate metal member, and the needle valve is connected to this intermediate metal member. A jet nozzle structure is formed by forming a seat portion on which the user sits.
［作用］
ノズル本体に昇降自在に収容された針弁がシー
ト部に着座されたときは、針弁の先端部の外周面
がノズル先端部の内周面に当接することがない。
このため、ノズル先端部及び中間金属部材とノズ
ル先端部との接合部に針弁の着座時に生じる衝撃
力が加えられなくなり、ノズル先端部の耐久性と
接続強度が大巾に向上されることになる。[Function] When the needle valve housed in the nozzle body so as to be movable up and down is seated on the seat portion, the outer circumferential surface of the tip of the needle valve does not come into contact with the inner circumferential surface of the nozzle tip.
Therefore, the impact force generated when the needle valve is seated is not applied to the nozzle tip and the joint between the intermediate metal member and the nozzle tip, and the durability and connection strength of the nozzle tip are greatly improved. Become.
また中間金属部材は低熱膨張係数をもちまた表
面硬化層を形成されたため耐摩耗性が向上されて
減りが少なく、熱膨張が極力抑えられて接続部の
接続強度が一定に保たれる。 Further, since the intermediate metal member has a low coefficient of thermal expansion and is formed with a hardened surface layer, its wear resistance is improved and there is little wear, thermal expansion is suppressed to the utmost, and the connection strength of the connection portion is maintained constant.
［実施例］
以下にこの発明の噴射ノズル構造の好適一実施
例を添付図面に基づいて説明する。[Embodiment] A preferred embodiment of the injection nozzle structure of the present invention will be described below with reference to the accompanying drawings.
第１図に示されるように円筒状のノズル本体１
内には、半径方向に過度なクリアランスを有して
針弁２が昇降自在に収容されている。このノズル
本体１はこの実施例では機械構造用炭素鋼材
（JIS規格）で構成される。ノズル本体１の先端に
は、リング状の中間金属部材３が一体的に接続さ
れており、この中間金属部材３の内周面の先端側
には上記針弁２のシート面２ａが気密に着座され
る円錐状のシート部３ａが形成されている。この
実施例にあつて中間金属部材３はインコロイまた
はコバール等の低熱膨張率をもつ金属材料から形
成される。中間金属部材３の他端には、セラミツ
クスにて焼成されたノズル先端部４が一体に接続
されており、このノズル先端部４は上記針弁２の
先端外周面に倣うように断面Ｖ字形に形成されて
いる。シート部３ａには表面に耐摩耗性を向上さ
せるための表面硬化層９が形成される。 As shown in FIG. 1, a cylindrical nozzle body 1
A needle valve 2 is accommodated therein with an excessive clearance in the radial direction so as to be able to move up and down. In this embodiment, the nozzle body 1 is made of carbon steel for mechanical structures (JIS standard). A ring-shaped intermediate metal member 3 is integrally connected to the tip of the nozzle body 1, and the seat surface 2a of the needle valve 2 is airtightly seated on the tip side of the inner peripheral surface of the intermediate metal member 3. A conical sheet portion 3a is formed. In this embodiment, the intermediate metal member 3 is made of a metal material having a low coefficient of thermal expansion, such as Incoloy or Kovar. A nozzle tip 4 fired from ceramics is integrally connected to the other end of the intermediate metal member 3, and the nozzle tip 4 has a V-shaped cross section so as to follow the outer peripheral surface of the tip of the needle valve 2. It is formed. A hardened surface layer 9 is formed on the surface of the sheet portion 3a to improve wear resistance.
この実施例では、シート部３ａの表面に平面応
力を加え、平面ひずみの増加に伴つて変形抵抗を
増加させることにより表面硬化層９が形成され
る。即ちこの実施例に於ける表面硬化層９は加工
硬化によつて得られる。ここで、表面硬化層９の
硬度は針弁２のシート面２ａの硬度に応じて所期
の硬度に設定される。一方、ノズル本体１のノズ
ル収容部７の表面硬度は、針弁２のステム部２ｂ
を収容する部分が高く、中間金属部材３との接合
部付近は低く設定される。ちなみに、ステム部２
ｂの収容部分がHRC55以上、接続部分付近がHB
56〜HB212の硬度に設定される。また、上記硬化
層９に針弁２のシート面２ａが着座されたときに
おいて、ノズル先端部４の内周面４ａと針弁２の
先端部の外周面との間には僅かなクリアランスを
保つように設定される。さらに、ノズル先端部４
には、そのノズル先端部４の傾斜方向に対して交
差する方向に開口された噴口５が形成されてお
り、またこの噴口５は実施例ではノズル先端部４
の軸方向に間隔をおいて複数形成されている。６
はノズル先端部４の内周面４ａに沿つて形成され
各噴口５を接続する溝で、この溝６により、各噴
口へ均等に燃料を案内し、燃料溜りをなくして、
噴口５のカーボンづまりを防止するものである。 In this embodiment, the surface hardening layer 9 is formed by applying plane stress to the surface of the sheet portion 3a and increasing the deformation resistance as the plane strain increases. That is, the surface hardened layer 9 in this embodiment is obtained by work hardening. Here, the hardness of the surface hardening layer 9 is set to a desired hardness according to the hardness of the seat surface 2a of the needle valve 2. On the other hand, the surface hardness of the nozzle accommodating portion 7 of the nozzle body 1 is
The part that accommodates the metal member 3 is set high, and the vicinity of the joint with the intermediate metal member 3 is set low. By the way, stem part 2
The storage part of b is H R C55 or more, and the area near the connection part is H B
Hardness is set from 56 to H B 212. Further, when the seat surface 2a of the needle valve 2 is seated on the hardened layer 9, a slight clearance is maintained between the inner circumferential surface 4a of the nozzle tip 4 and the outer circumferential surface of the tip of the needle valve 2. It is set as follows. Furthermore, the nozzle tip 4
is formed with a nozzle 5 which is opened in a direction crossing the direction of inclination of the nozzle tip 4, and this nozzle 5 is formed in the nozzle tip 4 in the embodiment.
A plurality of them are formed at intervals in the axial direction. 6
is a groove formed along the inner circumferential surface 4a of the nozzle tip 4 and connecting each nozzle 5, and this groove 6 guides the fuel evenly to each nozzle, eliminating fuel accumulation,
This prevents carbon from clogging the nozzle 5.
ところで、ノズル本体１と中間金属部材３とは
この実施例では摩擦圧接またはビーム溶接により
溶着され、また、中間金属部材３とセラミツク製
のノズル先端部４とはブレージング溶接または拡
散溶接によつて接続される。 By the way, the nozzle body 1 and the intermediate metal member 3 are welded together by friction welding or beam welding in this embodiment, and the intermediate metal member 3 and the ceramic nozzle tip 4 are connected by brazing welding or diffusion welding. be done.
さらに、噴口５はセラミツクの焼成と同時に形
成できるため、噴口５の形状を異形にすることや
噴口５を精度良く形成することができる。７ａは
燃料室、８は燃料通路である。 Further, since the nozzle 5 can be formed at the same time as the firing of the ceramic, the nozzle 5 can be made into an irregular shape and the nozzle 5 can be formed with high accuracy. 7a is a fuel chamber, and 8 is a fuel passage.
第２図には上記表面硬化層９の他の実施例が示
されている。 Another embodiment of the surface hardening layer 9 is shown in FIG.
同図において、表面硬化層９はこの実施例にあ
つては溶射によつて形成される。溶射材料として
はステライト（CO−Cr−Ｗ−ＣまたはCO−Cr
−MO−Ｃ合金）が採用される。ステライトは耐
摩耗性の他に耐熱、耐蝕性も高く、さらに溶接に
よる熱影響を受けても硬度劣化を生じない利点を
もつている。したがつて中間金属部材３にセラミ
ツク製のノズル先端部４がブレージング溶接され
た後も、接合後に於ける熱処理を不要とすること
ができる。 In this figure, a hardened surface layer 9 is formed by thermal spraying in this embodiment. Stellite (CO-Cr-W-C or CO-Cr
-MO-C alloy) is adopted. Stellite has high heat and corrosion resistance in addition to wear resistance, and has the advantage that its hardness does not deteriorate even when it is affected by heat from welding. Therefore, even after the ceramic nozzle tip 4 is brazed welded to the intermediate metal member 3, heat treatment after joining can be made unnecessary.
また、表面硬化層９の形成としてはステライト
に限らず超硬合金、Ni−Cr−Ｂ系合金を溶着さ
せても良く、セラミツクスを溶射しても良い。 Furthermore, the surface hardening layer 9 is not limited to stellite, but may be welded with cemented carbide, Ni-Cr-B alloy, or thermally sprayed with ceramics.
尚本実施例の説明で、シート部３ａ及びそのシ
ート部３ａに被覆形成される表面硬化層９を中間
金属部材３に形成する説明をしたが、中間金属部
材３をノズル本体部１とノズル先端部４とを接続
するためのものとして軸方向の厚さを薄くし、シ
ート部３ａ及び上記硬化層９をノズル本体１の先
端部側に形成してもよい。 In the description of this embodiment, the sheet portion 3a and the surface hardening layer 9 coated on the sheet portion 3a are formed on the intermediate metal member 3. The sheet portion 3a and the hardened layer 9 may be formed on the tip side of the nozzle body 1 by reducing the thickness in the axial direction to connect the sheet portion 4 to the nozzle body 1.
［発明の効果］
以上説明したことから明らかなように本発明の
噴射ノズル構造によれば次の如き優れた効果を発
揮できる。[Effects of the Invention] As is clear from the above explanation, the injection nozzle structure of the present invention can exhibit the following excellent effects.
(1) 針弁を昇降自在に収納するノズル本体の先端
に上記針弁が着座されるシート部を備えた中間
金属部材を接続し、その金属部材の他端にセラ
ミツクスから形成されて燃料の噴口を有するノ
ズル先端部を接続し、且つノズル先端部内周面
と針弁先端部外周面との間に針弁着座時に於け
る僅かなクリアランスをもたせたので針弁の着
座時に生じる衝撃力がセラミツク製のノズル先
端部及びノズル先端部と中間金属部材との接続
部に加えられなくなり耐久性を大巾に向上でき
る。(1) An intermediate metal member having a seat portion on which the needle valve is seated is connected to the tip of the nozzle body that accommodates the needle valve so as to be able to move up and down, and a fuel nozzle made of ceramic is connected to the other end of the metal member. By connecting the nozzle tip with a ceramic needle and providing a slight clearance between the inner circumferential surface of the nozzle tip and the outer circumferential surface of the needle valve tip when the needle valve is seated, the impact force generated when the needle valve is seated is suppressed by the ceramic material. The durability can be greatly improved since the nozzle tip and the connection part between the nozzle tip and the intermediate metal member are not affected.
(2) シート部に表面硬化層を形成したので、シー
ト部の耐摩耗性を大巾に向上できる。(2) Since a hardened surface layer is formed on the seat, the abrasion resistance of the seat can be greatly improved.
第１図は本発明の噴射ノズル構造の好適一実施
例を示す縦断面図、第２図は表面硬化層の他の実
施例を示す縦断面図である。
図中、１はノズル本体、２は針弁、３は中間金
属部材、３ａはシート部、４はノズル先端部、５
は噴口、６は溝、９は表面硬化層である。
FIG. 1 is a longitudinal sectional view showing a preferred embodiment of the injection nozzle structure of the present invention, and FIG. 2 is a longitudinal sectional view showing another embodiment of the surface hardening layer. In the figure, 1 is the nozzle body, 2 is the needle valve, 3 is the intermediate metal member, 3a is the seat part, 4 is the nozzle tip, 5
6 is a nozzle, 6 is a groove, and 9 is a surface hardening layer.
Claims (1)
ミツクスから形成されて噴口を有するノズル先端
部とをリング状の中間金属部材を介して一体に接
続し、この中間金属部材に上記針弁が着座される
シート部を形成し、該シート部の表面に表面硬化
層を設けたことを特徴とする噴射ノズル構造。 ２ 上記ノズル先端部が針弁先端部に倣つて形成
されると共に、上記シート部に針弁が着座された
ときに、ノズル先端部内周面と針弁先端部外周面
との間に僅かなクリアランスを有するように形成
された上記特許請求の範囲第１項記載の噴射ノズ
ル構造。 ３ 上記表面硬化層がシート部表面を加工硬化さ
せて形成された上記特許請求の範囲第１項記載の
噴射ノズル構造。 ４ 上記表面硬化層が耐熱、耐蝕、耐摩耗性材料
から構成された上記特許請求の範囲第１項記載の
噴射ノズル構造。 ５ 上記耐熱、耐蝕、耐摩耗性材料がセラミツク
スから構成された上記特許請求の範囲第４項記載
の噴射ノズル構造。 ６ 上記耐熱、耐蝕、耐摩耗性材料がステライト
から構成された上記特許請求の範囲第４項記載の
噴射ノズル構造。 ７ 上記中間金属部材が低熱膨脹係数をもつ金属
材料から構成された上記特許請求の範囲第１項記
載の噴射ノズル構造。 ８ 上記低熱膨脹係数をもつ金属材料がインコロ
イから構成された上記特許請求の範囲第７項記載
の噴射ノズル構造。 ９ 上記低熱膨脹係数をもつ金属材料がコバール
から構成された上記特許請求の範囲第７項記載の
噴射ノズル構造。 １０ 上記中間金属部材と上記ノズル本体とが圧
接により接合された上記特許請求の範囲第１項記
載の噴射ノズル構造。 １１ 上記中間金属部材と上記ノズル本体とがビ
ーム溶接により接合された上記特許請求の範囲第
１項記載の噴射ノズル構造。 １２ 上記中間金属部材と上記ノズル先端部とが
ブレージング溶接により接合された上記特許請求
の範囲第１項記載の噴射ノズル構造。 １３ 上記中間金属部材と上記ノズル先端部とが
拡散溶接により接合された上記特許請求の範囲第
１項記載の噴射ノズル構造。[Claims] 1. A nozzle body that accommodates a needle valve so as to be able to rise and fall freely and a nozzle tip formed from ceramics and having a nozzle are integrally connected via a ring-shaped intermediate metal member, and this intermediate metal member is An injection nozzle structure characterized in that a seat portion is formed on which the needle valve is seated, and a surface hardening layer is provided on the surface of the seat portion. 2. The nozzle tip is formed to follow the needle valve tip, and when the needle valve is seated on the seat, there is a slight clearance between the inner circumferential surface of the nozzle tip and the outer circumferential surface of the needle valve tip. The injection nozzle structure according to claim 1, which is formed to have the following. 3. The injection nozzle structure according to claim 1, wherein the surface hardening layer is formed by work-hardening the surface of the sheet portion. 4. The injection nozzle structure according to claim 1, wherein the surface hardening layer is made of a heat-resistant, corrosion-resistant, and wear-resistant material. 5. The injection nozzle structure according to claim 4, wherein the heat-resistant, corrosion-resistant, and wear-resistant material is made of ceramics. 6. The injection nozzle structure according to claim 4, wherein the heat-resistant, corrosion-resistant, and wear-resistant material is made of stellite. 7. The injection nozzle structure according to claim 1, wherein the intermediate metal member is made of a metal material having a low coefficient of thermal expansion. 8. The injection nozzle structure according to claim 7, wherein the metal material having a low coefficient of thermal expansion is made of Incoloy. 9. The injection nozzle structure according to claim 7, wherein the metal material having a low coefficient of thermal expansion is made of Kovar. 10. The injection nozzle structure according to claim 1, wherein the intermediate metal member and the nozzle body are joined by pressure contact. 11. The injection nozzle structure according to claim 1, wherein the intermediate metal member and the nozzle body are joined by beam welding. 12. The injection nozzle structure according to claim 1, wherein the intermediate metal member and the nozzle tip are joined by brazing welding. 13. The injection nozzle structure according to claim 1, wherein the intermediate metal member and the nozzle tip are joined by diffusion welding.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22191786A JPS6380062A (en) | 1986-09-22 | 1986-09-22 | Jet nozzle structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22191786A JPS6380062A (en) | 1986-09-22 | 1986-09-22 | Jet nozzle structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6380062A JPS6380062A (en) | 1988-04-11 |
| JPH0565714B2 true JPH0565714B2 (en) | 1993-09-20 |
Family
ID=16774182
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22191786A Granted JPS6380062A (en) | 1986-09-22 | 1986-09-22 | Jet nozzle structure |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6380062A (en) |
-
1986
- 1986-09-22 JP JP22191786A patent/JPS6380062A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6380062A (en) | 1988-04-11 |
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