JP2014159040A - Outer cylinder of injection sleeve for die casting machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prolong a life of a die cast sleeve and facilitate replacement by mounting an outer cylinder with a water-cooling mechanism so as to be in tapered-surface contact with the sleeve.SOLUTION: A cooling mechanism such as a water-cooling hole is not arranged on a sleeve which is a consumable part. An outer cylinder (a water jacket), which has a tapered surface outer circumference formed immediately beneath a periphery of a molten metal injection port of the sleeve and a tapered surface inner surface with the water-cooling mechanism, is mounted so as to be in tapered-surface contact with the sleeve. Heat transferability is secured by this means so as to prevent early damage in a periphery of a part immediately beneath the molten metal injection port which is considered as a bottleneck of a life of the sleeve, and also achieve easiness of attachment and detachment of the sleeve and the outer cylinder with the help of tapered-surface contact.

Description

本発明はダイカスト機に装着されるスリーブを、水冷機構を備えて効率よく冷却しかつ装着取外しが容易な外筒（ウォータージャケット）に関するものである。   The present invention relates to an outer cylinder (water jacket) that is provided with a water cooling mechanism to efficiently cool a sleeve that is mounted on a die casting machine and that can be easily mounted and removed.

アルミニウム、マグネシウム、亜鉛、銅等をベースとする合金の溶湯を鋳型へ注入する際に使用されるスリーブは鋳込む毎に、注入される合金溶湯から受ける作用に耐える耐熱強度、耐熱疲労強度、耐侵蝕性のほか、溶湯を押し出すためスリーブの,内部を往復するチップから受けるかじり摩耗に耐える耐摩耗性が要求される。そのためスリーブの材料はＪＩＳ ＳＫＤ６１あるいはこれに改良を加えた熱間工具鋼が一般に使用されている。さらに焼入れ焼もどし熱処理後、窒化処理も効果が有ってよく利用されている。なお、一般にスリーブの内面では特に溶湯の直撃を受ける注入口の直下部分が最初に損傷して、これがスリーブの寿命を決めてしまうケースが多い。
このスリーブの損傷は鋳物製品の品質を損なうため、ダイカスト作業現場では、鋳込みショット数の管理、スリーブの損耗程度の検査、さらには新品との交換作業に多くの工数をかけているため、スリーブには更なる寿命向上のニーズが極めて高いのが現状である。
そのため現状ではスリーブの溶湯注入口の直下部分近傍に水冷孔（図１）あるいは水冷溝（特許文献１および２の例）あるいは水冷パイブ（特許文献３の例）などを設けて冷却をすることによって、スリーブ材料の昇温による強度、耐摩耗性の低下を抑えて効果を得ているが、多くは大凡数ヶ月の寿命に留まっている。更に上記の水冷方式ではスリーブ自体の構造の複雑化による高コスト化と交換作業の煩雑さを招いている。 The sleeve used when injecting molten metal of an alloy based on aluminum, magnesium, zinc, copper, etc. into the mold is resistant to heat, fatigue resistance, In addition to erosion, the sleeve is required to have wear resistance to withstand galling wear from the sleeve that reciprocates inside the sleeve to push out the molten metal. Therefore, JIS SKD61 or a hot work tool steel obtained by improving the sleeve is generally used as a material for the sleeve. Further, after quenching and tempering heat treatment, nitriding treatment is effective and often used. In general, on the inner surface of the sleeve, in particular, the portion immediately below the injection port that receives the direct impact of the molten metal is first damaged, and this often determines the life of the sleeve.
Since this sleeve damages the quality of the cast product, it takes a lot of man-hours to manage the number of cast shots, inspect the sleeve for wear, and to replace it with a new one at the die casting work site. Currently, there is an extremely high need for further improvement of life.
Therefore, at present, a water cooling hole (FIG. 1), a water cooling groove (examples of Patent Documents 1 and 2), a water cooling pipe (example of Patent Document 3), or the like is provided in the vicinity of the portion immediately below the molten metal inlet of the sleeve for cooling. Although the effect of suppressing the decrease in strength and wear resistance due to the temperature rise of the sleeve material is obtained, most of them have a life of about several months. Furthermore, the above-described water cooling system increases the cost due to the complicated structure of the sleeve itself, and complicates the replacement work.

このためスリーブの長寿命化は大きな課題になっており、材料の見直しも試みられている。例えば、スリーブ内面の材質をセラミックスに置き換える考案もされてきた。下記特許文献４〜８はスリーブにセラミックス材の内筒または部分を設ける事を特徴として考案されているが、未解決な問題点特に母材の鋼と内筒のセラミックスの熱膨張差に起因する熱変形（バナナ現象）と予期したコストメリットが得られないという理由などから広く採用されるには至っていない。
本発明者等もかつて特許文献９で開示したとおり内面に硬質物質をプラズマ溶射したスリーブを試作したが、期待した長寿命を得るには至らなかった。 For this reason, extending the life of the sleeve has become a major issue, and attempts have been made to review the material. For example, it has been devised to replace the material of the sleeve inner surface with ceramics. The following Patent Documents 4 to 8 are devised with the feature that the sleeve is provided with the inner cylinder or part of the ceramic material, but unsolved problems are caused by the difference in thermal expansion between the steel of the base material and the ceramic of the inner cylinder. It has not been widely adopted for reasons such as thermal deformation (banana phenomenon) and the expected cost advantage.
The inventors of the present invention have also made a trial manufacture of a sleeve in which a hard substance is plasma sprayed on the inner surface as disclosed in Patent Document 9, but did not achieve the expected long life.

以上のとおり、スリーブを長寿命化するために、スリーブを水で冷却する方法と、スリーブの材料を改革する方法が図られてきた背景技術はあったが決め手を欠いていた。   As described above, in order to extend the life of the sleeve, there has been a background technique in which a method for cooling the sleeve with water and a method for reforming the material of the sleeve have been attempted, but lack of conclusiveness.

特開平６−３４４１０７JP-A-6-344107 特開２０１１−２０６８２７JP2011-206827 特開２００３−１３６２１３JP 2003-136213 A 公開特許公報昭６１−１０３６５８Published Patent Publication No. 61-103658 実用新案登録公報第２５３７６６６Utility Model Registration Gazette No. 2537666 実用新案公報平７−４７１６９Utility Model Publication No. 7-47169 実用新案公報平７−４１５５７Utility Model Publication No. 7-41557 実用新案公報平７−７０１０Utility Model Gazette Hei 7-7010 特開平１１−３２００６６JP-A-11-320066

なしNone

本発明は上記の背景を整理して、スリーブの昇温を効率よく防いで材料の強度を確保して、かつ寿命時のスリーブの着脱を容易にすることを課題とした。そこで消耗品であるスリーブには水冷機構を付けないで簡素化、低コスト化し、交換作業を容易にする。スリーブで最初に損傷する溶湯注入口の直下部分には熱移動しやすい構造でかつスリーブとの着脱が容易な水冷機構を内蔵する外筒を発明することであった。   An object of the present invention is to arrange the above background, to efficiently prevent the temperature rise of the sleeve, to secure the strength of the material, and to easily attach and detach the sleeve at the lifetime. Therefore, the sleeve, which is a consumable item, is simplified and reduced in cost without a water cooling mechanism, and the replacement work is facilitated. The inventor has invented an outer cylinder with a built-in water-cooling mechanism that is easy to move and detach from the sleeve, directly under the melt inlet that is first damaged by the sleeve.

そのためスリーブ外面と外筒内面をテーパー面当たりにして嵌め込み、取り外しが極めて容易でかつ面接触しやすく、それによって熱伝導しやすくした。さらにこの外筒は図２に示されるように通常の円筒形でなく、軸方向に沿って切欠きを持たせて開いた構造として溶湯注入口を塞がず、かつスリーブ嵌め込み時の弾性変形に対しても拘束力を弱めて余裕のある形状とした。   Therefore, the outer surface of the sleeve and the inner surface of the outer cylinder are fitted into the tapered surface, and the removal is extremely easy and the surface is easily contacted, thereby facilitating heat conduction. Further, as shown in FIG. 2, this outer cylinder is not an ordinary cylindrical shape, but has an open structure with a notch along the axial direction, and does not block the molten metal inlet, and is elastically deformed when the sleeve is fitted. In contrast, the restraining force was weakened to provide a shape with a margin.

アルミニウム合金のダイカストの場合、水冷孔をつけた冷却機構付きスリーブの実施例１（図１)の交換寿命は数ヶ月程度であったが、実施例２（図２）のように溶湯注入口の直下部分に本発明の外筒を取り付けると、この部分の損耗発生は遅れが確認され、スリーブの寿命が大幅に伸びた。さらにテーパー面加工は要するが水冷機構がないためスリーブは低コスト化し、新たに本発明の水冷機構付き外筒（ウォータージャケット）は交換の必要はなく、その製作コストを含めても大きなメリットが出た。また付随して、スリーブに水冷用の穴加工をなくしたことにより、穴加工面の切り欠けが原因でスリーブが破損する突発事故もなくなった。さらにスリーブ寿命の向上とあいまってスリーブ内部をショット毎に往復して溶湯を押し出すチップの寿命も延長する付随効果が見られた。これらの結果スリーブの低価格化、保守のための工数削減とダイカスト製品品質の安定化に大きく寄与した。   In the case of aluminum alloy die-casting, the replacement life of the sleeve with the cooling mechanism with water cooling holes in Example 1 (FIG. 1) was about several months, but as in Example 2 (FIG. 2), When the outer cylinder of the present invention was attached to the portion directly underneath, the occurrence of wear in this portion was confirmed to be delayed, and the life of the sleeve was greatly extended. In addition, taper surface processing is required but there is no water cooling mechanism, so the cost of the sleeve is reduced, and the outer cylinder (water jacket) with a water cooling mechanism of the present invention does not need to be replaced. It was. In addition, by eliminating the hole for water cooling in the sleeve, there was no sudden accident that the sleeve was damaged due to notches in the hole processing surface. In addition, along with the improvement of the sleeve life, there was an accompanying effect of extending the life of the tip that reciprocates the inside of the sleeve for each shot to push out the molten metal. As a result, it contributed greatly to lowering the price of the sleeve, reducing the number of man-hours for maintenance, and stabilizing the quality of die-cast products.

図１は従来のスリーブの外観図である。（実施例１）FIG. 1 is an external view of a conventional sleeve. Example 1 図２は改善したスリーブと本発明の外筒の組み合わせ図である。（実施例２）FIG. 2 is a combination view of the improved sleeve and the outer cylinder of the present invention. (Example 2)

ダイカスト機用の射出スリーブは水冷機構を不要とし、溶湯注入口付近の外周にテーパー面加工するだけで、本発明の外筒（ウオータージャケット）を取り付けることによって稼動時の昇温が抑えられるため寿命が延長し、さらに寿命にいたっても取り外しがテーパー面当たりなので容易である。本発明の外筒（ウオータージャケット）は内部に水流ができて冷却できる構造であればよく、内周面はスリーブの外周テーパー面に呼応した傾斜角と面粗度を持てば良い。   The injection sleeve for die-casting machines does not require a water cooling mechanism, and only has a tapered surface on the outer periphery in the vicinity of the molten metal inlet. However, even if it reaches the end of its service life, it is easy to remove because it comes in contact with the tapered surface. The outer cylinder (water jacket) of the present invention only needs to have a structure in which water can flow inside and can be cooled, and the inner peripheral surface only needs to have an inclination angle and surface roughness corresponding to the outer peripheral tapered surface of the sleeve.

図2は、本発明の水冷機構を備えた外筒とスリーブを組み立てた外観であって、外筒には図に示す通りの冷却水の入口(図ではIN)と出口(OUT)がある。   FIG. 2 is an external view of the outer cylinder and the sleeve provided with the water cooling mechanism of the present invention. The outer cylinder has an inlet (IN) and an outlet (OUT) of cooling water as shown in the figure.

損耗交換は避けられないダイカストスリーブ自体には水冷機構を付けず低コストにして、スリーブ外筒に本発明の水冷機構付き外筒を取り付けることによって、スリーブの長寿命化と交換の容易さを図る事ができる利点があり、簡易に従来からのダイカストマシン用スリーブに広く応用出来る可能性がある。スリーブと水冷機構付き内筒（ウォータージャケット）の着脱、熱交換にテーパー面あたりにしたことは利用の可能性が大きい。
Replacement of wear and die is inevitable. The die-casting sleeve itself is not provided with a water cooling mechanism, and the cost is low. By attaching the outer cylinder with the water cooling mechanism of the present invention to the sleeve outer cylinder, the life of the sleeve is extended and the replacement is facilitated. There is an advantage that it can be applied to a conventional sleeve for a die casting machine. The possibility of using the sleeve and the inner cylinder (water jacket) with a water cooling mechanism around the tapered surface for attaching / detaching and heat exchange is great.

Claims (3)

アルミニウム合金その他の合金のダイカスト機に取り付けられ、これらの溶湯の注入口と排出口を持つ射出シリンダー（スリーブ）に取り付ける水冷機構を持つ外筒（ウォータージャケット）。   An outer cylinder (water jacket) attached to an aluminum alloy or other alloy die-casting machine and attached to an injection cylinder (sleeve) with an inlet and outlet for these molten metals. 請求項１において、スリーブと外筒がテーパー面で嵌合することを特徴とする外筒。 The outer cylinder according to claim 1, wherein the sleeve and the outer cylinder are fitted with a tapered surface. 請求項１において、外筒が円筒でなく円周方向に切り欠けを持って開放されていることを特徴とする外筒。 2. The outer cylinder according to claim 1, wherein the outer cylinder is not a cylinder but is opened with a notch in the circumferential direction.

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