JPH0476005B2 - - Google Patents
Info
- Publication number
- JPH0476005B2 JPH0476005B2 JP25620886A JP25620886A JPH0476005B2 JP H0476005 B2 JPH0476005 B2 JP H0476005B2 JP 25620886 A JP25620886 A JP 25620886A JP 25620886 A JP25620886 A JP 25620886A JP H0476005 B2 JPH0476005 B2 JP H0476005B2
- Authority
- JP
- Japan
- Prior art keywords
- core material
- valve
- core
- manufacturing
- hot
- 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
Links
- 239000000463 material Substances 0.000 claims description 39
- 239000011162 core material Substances 0.000 claims description 35
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 13
- 238000004519 manufacturing process Methods 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 12
- 229910002804 graphite Inorganic materials 0.000 claims description 8
- 239000010439 graphite Substances 0.000 claims description 8
- 239000010959 steel Substances 0.000 claims description 6
- 229910000831 Steel Inorganic materials 0.000 claims description 5
- 238000005242 forging Methods 0.000 claims description 5
- 238000000465 moulding Methods 0.000 claims description 5
- 239000000843 powder Substances 0.000 claims description 5
- 229910052799 carbon Inorganic materials 0.000 claims description 4
- 239000000919 ceramic Substances 0.000 claims description 4
- 238000001192 hot extrusion Methods 0.000 claims description 4
- 239000004576 sand Substances 0.000 claims description 3
- 230000005484 gravity Effects 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 claims description 2
- 238000003466 welding Methods 0.000 description 8
- 230000000694 effects Effects 0.000 description 3
- 238000001125 extrusion Methods 0.000 description 3
- 238000005266 casting Methods 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005553 drilling Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 229910000861 Mg alloy Inorganic materials 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 239000011796 hollow space material Substances 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000005121 nitriding Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 238000009721 upset forging Methods 0.000 description 1
- 239000013585 weight reducing agent Substances 0.000 description 1
Landscapes
- Forging (AREA)
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、内燃機関に使用する軽量エンジンバ
ルブおよび中空エンジンバルブの製造方法に関す
る。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing lightweight engine valves and hollow engine valves for use in internal combustion engines.
従来の技術
内燃エンジンのエンジンバルブは、エンジンの
高速高出力化の要求に伴つて、高熱雰囲気に耐え
ることは勿論、弁の慣性から生じる弊害を回避す
るためになるべく軽量であることが望まれてい
る。BACKGROUND OF THE INVENTION With the demand for high-speed, high-output engines, engine valves for internal combustion engines are desired not only to withstand high-temperature atmospheres but also to be as lightweight as possible to avoid adverse effects caused by inertia of the valves. There is.
軽量化の対策の１つとして傘部に対してバルブ
ステム部分を細くする試みがなされ、かつ、実用
化されているが、軸径の強度上の限界のため軽量
化には限度がある。又バルブの軽量化の他の試み
としては、バルブ自体を中空にすることが行なわ
れている。例えば実公昭60−34725号明細書は、
鋼素材或いは弁頭及び弁軸を形成した予備成形品
に孔あけ加工を施して中空にし、できた孔にアル
ミニウム合金或いはマグネシウム合金の芯を装填
固定したエンジンバルブを開示してある。 As one measure to reduce weight, attempts have been made to make the valve stem portion thinner than the umbrella portion, and this has been put into practical use, but there is a limit to the weight reduction due to the strength limit of the shaft diameter. Another attempt to reduce the weight of the valve is to make the valve itself hollow. For example, the specification of Utility Model Publication No. 60-34725 is
An engine valve has been disclosed in which a steel material or a preformed product having a valve head and a valve stem is hollowed out by drilling, and a core made of aluminum alloy or magnesium alloy is charged and fixed into the hole.
又特公昭51−29106号明細書或いは特公昭51−
29506号明細書には、パイプ素材を用い、パイプ
の内側に捨中子となるインサートを挿入するか或
いは、芯となるインサートを挿入接着した後アプ
セツト鍛造及び熱間プレス加工を行つて製造され
るエンジンバルブが開示されている。さらに中空
バルブの傘部、ステム部分及び軸端部分を別々に
用意した後これらを溶接することも行なわれてい
る。バルブの軽量化のさらに別の試みとしてバル
ブ自体を軽金属で作ることも行なわれている。 Also, Specification of Special Publication No. 51-29106 or Special Publication No. 51-
Specification No. 29506 states that the pipe is manufactured by using a pipe material, inserting an insert to serve as a waste core inside the pipe, or inserting and adhering a core insert, and then performing upset forging and hot pressing. Engine valves are disclosed. Furthermore, it has also been practiced to prepare the cap, stem, and shaft end portions of a hollow valve separately and then weld them together. Another attempt to reduce the weight of the valve is to make the valve itself from a light metal.
発明が解決しようとする問題点
しかしながら、このような試みでエンジンバル
ブを軽量化するものにあつては、中空化するため
に正確、精密な孔あけ加工を必要としたり、捨中
子となるインサトを削出し或いは腐食酸による溶
出によつて除去する加工を必要としたり、或いは
芯となるインサートやバルブの各部分を溶接しな
くてはならないため、加工が複雑かつ困難で製造
コストが高くなりやすいという問題点があつた。
又軽金属でエンジンバルブを製造する場合には、
材料が高価であり、加工が困難な上に窒化処理等
により表面を硬化させる必要があるため、特殊エ
ンジンを除いては一般的でないという問題点があ
つた。Problems to be Solved by the Invention However, when attempting to reduce the weight of engine valves in this way, accurate and precise drilling is required to make them hollow, and inserts that become waste cores are required. The process is complicated and difficult, and the manufacturing cost tends to be high because the core insert and each part of the valve must be welded. There was a problem.
Also, when manufacturing engine valves from light metals,
The material is expensive, it is difficult to process, and the surface needs to be hardened by nitriding, so it is not common except for special engines.
本発明の目的は上述した問題点を除去し、煩雑
な加工を行うことなく製造することのできる軽量
エンジンバルブの製造方法を提供することにあ
る。 An object of the present invention is to provide a method for manufacturing a lightweight engine valve that eliminates the above-mentioned problems and can be manufactured without complicated processing.
問題点を解決するための手段
本発明は、エンジンバルブを製造するにあた
り、中空円筒形の耐熱鋼素材に、前記素材に比べ
比重及び熱膨張係数が小さく、熱間鍛造温度で溶
融しない炭素、黒鉛、鋳物砂、セラミツク粉末等
から成る芯材を、前記素材の一端に片寄らせて装
填し前記素材の芯材が片寄つている側と反対側の
端部をかしめ、前記芯材と装填された素材とを加
熱した後、前記素材の前記孔の開口と反対側に熱
間押出し成形によつて芯材の入つたバルブステム
部分を形成し、次いで前記素材の残部に熱間プレ
ス据込成形を施して傘部を形成し、次いで前記芯
材を片寄らせた側より芯材を一部或いは全部取出
した後、栓により前記孔の開口部を溶接密栓する
ことを特徴とする。Means for Solving the Problems The present invention provides a method for manufacturing engine valves using carbon and graphite, which have a smaller specific gravity and coefficient of thermal expansion than the aforementioned materials, and which do not melt at hot forging temperatures. , a core material made of foundry sand, ceramic powder, etc. is loaded in a biased manner to one end of the material, and the end of the material on the opposite side from where the core material is biased is caulked, and the core material and the loaded material are After heating the material, a valve stem portion containing a core material is formed by hot extrusion molding on the opposite side of the hole opening of the material, and then hot press upsetting is performed on the remaining part of the material. The method is characterized in that after a part or all of the core material is taken out from the side where the core material is shifted, the opening of the hole is welded and sealed with a plug.
以下、図面により本発明を説明する。 The present invention will be explained below with reference to the drawings.
実施例
第１図は本発明による軽量エンジンバルブの製
造過程を示す一例の概略断面図である。中空円筒
形の耐熱鋼或いはチタン合金の棒材を用意し、こ
れを所定の寸法に切断して素材１を得る。次いで
第１図ａに示すように、素材１の孔２に素材より
短い芯材３を装填するとともに、芯材３の両端に
芯材脱落防止用の円板状の蓋４，５を配置する。
芯材は、素材に比べ、軽量で熱膨張係数が小さ
く、熱間鍛造温度で溶融しない物質であることが
必要であり、例えば炭素、黒鉛、鋳物砂又はセラ
ミツク粉末等が好ましい。本例では黒鉛を使用す
る。芯材が粉末状のもの、又はこれを固めたもの
である場合、後の工程で芯材が素材から脱落する
おそれがあり、このため蓋４，５が取付けられて
いる。蓋４は、素材のエンジンバルブの傘部とな
るべき側に、その外面を素材の端面と面一になる
ように孔２に挿入されている。蓋５は、素材のエ
ンジンバルブのステム部分となるべき側に挿入さ
れている。これらの蓋は、中心に夫々小孔４ａ，
５ａを有しても良い。この場合後の熱間鍛造時に
圧縮された芯材内の空気を孔４ａ，５ａを通すこ
とにより、一部の芯材が素材より飛び出ることを
防止する事ができる。Embodiment FIG. 1 is a schematic sectional view of an example showing the manufacturing process of a lightweight engine valve according to the present invention. A hollow cylindrical heat-resistant steel or titanium alloy bar is prepared and cut into a predetermined size to obtain the material 1. Next, as shown in FIG. 1a, a core material 3 shorter than the material is loaded into the hole 2 of the material 1, and disk-shaped lids 4 and 5 are placed at both ends of the core material 3 to prevent the core material from falling off. .
The core material needs to be a material that is lighter than the raw material, has a smaller coefficient of thermal expansion, and does not melt at hot forging temperatures, and is preferably made of carbon, graphite, foundry sand, ceramic powder, or the like. In this example, graphite is used. If the core material is powdered or hardened, there is a risk that the core material will fall off from the material in a later process, and for this reason the lids 4 and 5 are attached. The lid 4 is inserted into the hole 2 on the side of the material that is to become the umbrella part of the engine valve, with its outer surface flush with the end surface of the material. The lid 5 is inserted into the side of the material that is to become the stem portion of the engine valve. These lids each have a small hole 4a in the center,
5a. In this case, by passing the air in the core material compressed during subsequent hot forging through the holes 4a and 5a, it is possible to prevent part of the core material from popping out from the material.
次いで第１図ｂに示すように素材１の蓋５の側
をかしめ芯材を素材にしつかりと固定する。 Next, as shown in FIG. 1b, the lid 5 side of the material 1 is caulked to firmly fix the core material to the material.
次に芯材３を孔３に装填した素材１を熱間押出
成形に適した所定温度まで加熱し、第２図の押出
成形用のダイ６にこの加熱された素材１を挿入
し、ポンチ７で素材１及び蓋４にこれらの面一と
なつた端面から圧縮を加えて反対側の端からバル
ブステム８として熱間前方押出しを行う。バルブ
ステム８が所定長さ押出し成形されたとき、ダイ
内には弁頭部となるべき部分９が残部として残
る。第１図ｃに示すように、素材中の芯材黒鉛は
素材とともに押出される結果、ステム８の中心一
様に入込む。 Next, the material 1 with the core material 3 loaded into the hole 3 is heated to a predetermined temperature suitable for hot extrusion molding, the heated material 1 is inserted into the extrusion molding die 6 shown in FIG. Then, compression is applied to the raw material 1 and the lid 4 from their flush end surfaces, and hot forward extrusion is performed from the opposite end to form the valve stem 8. When the valve stem 8 is extruded to a predetermined length, a portion 9 that is to become the valve head remains in the die. As shown in FIG. 1c, the core graphite in the material is extruded together with the material, and as a result, it enters the center of the stem 8 uniformly.
次にこれをエンジンバルブとするため、第３図
に示すようにダイ１０に挿入したポンチ１１で部
分９に熱間プレス据込成形を施して所定形状を有
する傘部１２を形成する。第１図ｄに傘部１２の
据込形成後ダイ１０より取出されたエンジンバル
ブを示す。 Next, in order to use this as an engine valve, as shown in FIG. 3, hot press upsetting is performed on the portion 9 using a punch 11 inserted into a die 10 to form an umbrella portion 12 having a predetermined shape. FIG. 1d shows the engine valve taken out from the die 10 after the head portion 12 has been formed by upsetting.
次いで第１図ｅに示すように、傘部１２におけ
る孔２の開口部分から蓋４及び芯材の一部を取出
し、耐熱鋼より成る栓１３によつて孔２の開口部
分を溶接で密栓する。この溶接としては抵抗溶
接、TIG溶接、電子ビーム溶接摩擦溶接等を適用
することができる。最後にエンジンバルブに軸端
部１４を形成する。軸端部１４は第１図ｅに示す
ように直接形成してもよく、第４図ａ及びｂに示
すようにステム部分を加工した後、素材と別の部
品１４ａ，１４ｂを溶接して形成するようにして
もよい。 Next, as shown in FIG. 1e, the lid 4 and a part of the core material are taken out from the opening of the hole 2 in the umbrella part 12, and the opening of the hole 2 is sealed by welding with a plug 13 made of heat-resistant steel. . As this welding, resistance welding, TIG welding, electron beam welding, friction welding, etc. can be applied. Finally, the shaft end portion 14 is formed on the engine valve. The shaft end portion 14 may be formed directly as shown in FIG. 1e, or by welding the material and other parts 14a and 14b after processing the stem portion as shown in FIGS. 4a and 4b. You may also do so.
第５図は、本発明によるエンジンバルブの製造
方法の他の例によつて作られた中空エンジンバル
ブを示す一部断面図である。この方法では、第１
図の実施例とは密栓工程だけが異なるため、第１
図と同様の説明を省略する。前と同様に、熱間押
出し成形及び熱間プレス据込成形を経てエンジン
バルブを作り、傘部１２表面にある孔２の開口部
より芯材である黒鉛３を全部破砕して取出し、エ
ンジンバルブを中空化する。次いで溶接によつて
栓１３′を傘部１２に固定し密栓する。 FIG. 5 is a partial sectional view showing a hollow engine valve manufactured by another example of the method for manufacturing an engine valve according to the present invention. In this method, the first
The only difference from the example shown in the figure is the sealing process.
Descriptions similar to those in the figures will be omitted. As before, the engine valve is made through hot extrusion molding and hot press upsetting, and all of the graphite 3 that is the core material is crushed and taken out from the opening of the hole 2 on the surface of the umbrella part 12, and the engine valve is made. Hollow out. Next, the stopper 13' is fixed to the umbrella part 12 by welding, and the stopper is sealed.
中空軽量エンジンバルブの場合には、中空内に
金属ナトリウムを封入して、冷却効果の向上を図
ることができる。 In the case of a hollow lightweight engine valve, metallic sodium can be sealed inside the hollow space to improve the cooling effect.
効 果
以上の説明から明らかなように本発明による軽
量エンジンバルブの製造方法によれば、中空円筒
状の耐熱鋼素材を使用して、この中心に黒鉛、炭
素、セラミツクス粉末等の芯材を装填した後、熱
間鍛造によりバルブステム部と傘部とを成形する
ようにしたため、極めて軽いエンジンバルブを簡
単かつ低コストで製造することができる。中空円
筒状の素材は、種々の形状寸法のものを少ない加
工工数で簡単に得ることができる利点がある。
又、内部に黒鉛芯材を封入した軽量バルブでは、
黒鉛が潤滑性に優れるため、エンジンの高速回転
時において素材との間に微動摩耗を起こすことが
ない。Effects As is clear from the above explanation, according to the method of manufacturing a lightweight engine valve according to the present invention, a hollow cylindrical heat-resistant steel material is used, and a core material such as graphite, carbon, or ceramic powder is loaded in the center of the hollow cylindrical heat-resistant steel material. After that, the valve stem portion and the umbrella portion are formed by hot forging, so that an extremely light engine valve can be manufactured easily and at low cost. Hollow cylindrical materials have the advantage that they can be easily obtained in various shapes and sizes with a small number of processing steps.
In addition, for lightweight valves with a graphite core sealed inside,
Graphite has excellent lubricity, so there is no slight wear between it and the material when the engine rotates at high speeds.
さらに本発明の製造方法によれば、熱間鋳造前
に芯材を装填するため、鋳造後芯材を素材内部に
隙間なく、特に粉末芯材では極めて密に、封入す
ることができる効果もある。 Furthermore, according to the manufacturing method of the present invention, since the core material is loaded before hot casting, it is possible to encapsulate the core material inside the material after casting without any gaps, especially when using a powder core material, extremely tightly. .
第１図ａ〜ｅは、本発明による軽量エンジンバ
ルブの製造方法を示す一例の概略断面図、第２図
は、軽量エンジンバルブのバルブステムを熱間前
方押出しにより成形するダイ及びポンチを示す概
略図、第３図は、本発明による軽量エンジンバル
ブに熱間プレス据込成形によつて傘部を形成する
ダイ及びポンチを示す概略図、第４図はエンジン
バルブの軸端部の他の例を示す部分断面図、第５
図は、本発明のエンジンバルブの製造方法の他の
例による軽量エンジンバルブを示す一部切欠き断
面図である。
１……素材、３……芯材、４，５……蓋、８…
…バルブステム部分、１２……傘部分、１３……
栓。
Figures 1 a to e are schematic cross-sectional views of an example of the method for manufacturing a lightweight engine valve according to the present invention, and Figure 2 is a schematic diagram showing a die and punch for forming the valve stem of the lightweight engine valve by hot forward extrusion. Fig. 3 is a schematic diagram showing a die and punch for forming an umbrella part by hot press upsetting on a lightweight engine valve according to the present invention, and Fig. 4 is another example of the shaft end of an engine valve. 5th partial cross-sectional view showing
The figure is a partially cutaway sectional view showing a lightweight engine valve according to another example of the engine valve manufacturing method of the present invention. 1...Material, 3...Core material, 4, 5...Lid, 8...
...Valve stem part, 12... Umbrella part, 13...
plug.
Claims (1)
筒形の耐熱鋼素材に、前記素材比べ比重及び熱膨
張係数が小さく、熱間鍛造温度で溶融しない炭
素、黒鉛、鋳物砂、セラミツク粉末等から成る芯
材を、前記素材の一端に片寄らせて装填し前記素
材の芯材が片寄つている側と反対側の端部をかし
め、前記芯材と装填された素材とを加熱した後、
前記素材の前記孔の開口と反対側に熱間押出し成
形によつて芯材の入つたバルブステム部分を形成
し、次いで前記素材の残部に熱間プレス据込成形
を施して傘部を形成し、次いで前記芯材を片寄ら
せた側より芯材を一部或いは全部取出した後、栓
により前記孔の開口部を溶接密栓することを特徴
とする軽量エンジンバルブの製造方法。1. In manufacturing engine valves, a core material made of carbon, graphite, foundry sand, ceramic powder, etc., which has a smaller specific gravity and coefficient of thermal expansion than the above-mentioned materials and does not melt at hot forging temperatures, is added to a hollow cylindrical heat-resistant steel material. , after loading the material offset to one end, caulking the end of the material opposite to the side where the core material is offset, and heating the core material and the loaded material,
A valve stem portion containing a core material is formed by hot extrusion molding on the opposite side of the opening of the hole of the material, and then a cap portion is formed by hot press upsetting molding on the remaining part of the material. 2. A method for manufacturing a lightweight engine valve, characterized in that, after removing part or all of the core material from the side where the core material is shifted, the opening of the hole is welded and sealed with a plug.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25620886A JPS63205410A (en) | 1986-10-28 | 1986-10-28 | Manufacture of lightweight engine valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25620886A JPS63205410A (en) | 1986-10-28 | 1986-10-28 | Manufacture of lightweight engine valve |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63205410A JPS63205410A (en) | 1988-08-24 |
| JPH0476005B2 true JPH0476005B2 (en) | 1992-12-02 |
Family
ID=17289421
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP25620886A Granted JPS63205410A (en) | 1986-10-28 | 1986-10-28 | Manufacture of lightweight engine valve |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63205410A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3929534A1 (en) * | 1989-09-06 | 1991-03-28 | Daimler Benz Ag | METHOD FOR PRODUCING A VALVE |
| JP2008000768A (en) * | 2006-06-20 | 2008-01-10 | Aisan Ind Co Ltd | Method for production of engine valve |
-
1986
- 1986-10-28 JP JP25620886A patent/JPS63205410A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63205410A (en) | 1988-08-24 |
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