JPS5832518A - Manufacture of extruded shape material - Google Patents

Abstract

PURPOSE:To obtain a small-sized and precise extruded shape material due to achieving of a constant-temperature extrusion by controlling the extrusion speed while keeping the delivery side of a die under conditions insulated from the effects of the ambient air, and keeping said delivery side at a constant temperature. CONSTITUTION:In a extruder wherein a extruded shape is pushed out from a die 1 to the delivery side 3 thereof, a means 5 for preventing the ambient air inflow is provided in a cavity 4 formed in the side 3 to keep the atomsphere in the cavity 4 constant. Further a temperature detector 6 detects the atmosphere temperature in the cavity 4 to feed back the detected results to the extruder and controls the extruding speed to attain a constant-temperature extrusion at the die delivery side 3, thereby improving dimensional accuracy in the small- sized or extremely small extruded section susceptible to temperature changes. It is desirable that an insulating plate, screen, or air curtain, etc are used as said means and the cavity 4 is a construction poor in heat transmission.

Description

【発明の詳細な説明】 一般に押出型材の押出しに当って加工、熱が発生し、こ
の加工熱は押出速度が早い程、また押出比（ビレット面
積と型材面積との比）が大きい程、発生量が大である。Detailed Description of the Invention In general, processing heat is generated during extrusion of an extruded mold material, and the faster the extrusion speed and the larger the extrusion ratio (ratio of billet area to mold material area), the more heat is generated. The quantity is large.

ところで、押出温度を高くすれば、ビレットは軟化し押
出しやすくなる反面、ダイスとの焼付き、押出機のわれ
などが起り易く、押出温度が低すぎると押出機の容量が
足らず押出し不能となる。By the way, if the extrusion temperature is increased, the billet becomes softer and easier to extrude, but on the other hand, it is more likely to seize with the die and crack the extruder, and if the extrusion temperature is too low, the capacity of the extruder becomes insufficient and extrusion becomes impossible.

上記した所から、従来は適当な押出温度を得るために主
に適当な押出速度を取るようにコントロールし、最良の
押出材が得られるようにしていた。From the above points, conventionally, in order to obtain an appropriate extrusion temperature, the extrusion speed was mainly controlled to obtain the best extruded material.

しかし乍ら、このようにして押出材が最適温度で押出さ
れたにも拘らず、ダイスを通過した押出形材は、押出時
の温度変化にくらべて外気の流入によシ温度が変化しや
すく、かつ約４００℃〜５００℃に達する押出温度に比
してかなり低温の外気と接触しながら冷却されて行く“
ことになる。However, even though the extruded material is extruded at the optimum temperature in this way, the temperature of the extruded material passing through the die is more likely to change due to the inflow of outside air than the temperature change during extrusion. , and is cooled while coming into contact with outside air, which is much lower than the extrusion temperature, which reaches approximately 400°C to 500°C.
It turns out.

したがって、押出形材の寸法精度の点から考慮した場合
には、従来の押出方法は最良のものとは言えず、たとえ
ば押出形材が小型ないしは極く小型の場合でかつ寸法精
度を向上したとしても、ダイス出口側温度のコントロー
ルなしには寸法精度の向上は望むべくもないと言っても
過言ではない。Therefore, when considering the dimensional accuracy of the extruded shape, the conventional extrusion method cannot be said to be the best. For example, if the extruded shape is small or extremely small and the dimensional accuracy is improved, However, it is no exaggeration to say that there is no hope of improving dimensional accuracy without controlling the temperature at the exit side of the die.

この発明は上記したような従来見過されていたダイス出
口側の温度変化の振れ幅も極く小とすることによシ、小
型又は極く小型でしかも精密な押出形材を提供すること
を目的とするものである。The present invention aims to provide a small or very small yet precise extruded shape by minimizing the amplitude of the temperature change on the die exit side, which has been overlooked in the past. This is the purpose.

次にこの発明を添付図面にしたがって説明する０ 図において、１はダイスであって、押出形材２はこのダ
イス１からダイス出口側３へ押し出されるようになって
いる。このダイス出口＄１１１３に形成される空所４に
おいて外気流入防止手段５を構成して前記空所４内を一
定の雰囲気に保つようにすると共に、この空所４に温度
検出部６を設けるのである。Next, the present invention will be described with reference to the accompanying drawings. In the drawings, 1 is a die, and the extruded section 2 is extruded from the die 1 toward the die outlet side 3. Outside air inflow prevention means 5 is configured in the cavity 4 formed at the die outlet $1113 to maintain a constant atmosphere inside the cavity 4, and a temperature detection section 6 is provided in this cavity 4. be.

前記外気流入防止手段５としては種々の形式のものが考
えられるが、しやへい板、スクリーン、エヤーカーテン
（この場合窒素ガスの混入を行うこともある）が一般的
であり、いずれの場合も形材２の導出部分以外をふさい
で前記空所４内の雰囲気を一定に保つようにするのであ
る。なお、前記空所４を形成する部材自体についても熱
移動の点で熱伝導の悪い材料を選んだり又は熱伝導が悪
くなるように積層構造としたりするのが望ましい。Various types of outside air inflow prevention means 5 can be considered, but in general, a shield plate, a screen, and an air curtain (in which case nitrogen gas may be mixed) are considered. The atmosphere within the space 4 is kept constant by closing off the section of the section 2 other than the lead-out part. It is preferable that the member forming the cavity 4 itself be made of a material that has poor thermal conductivity in terms of heat transfer, or that it has a laminated structure so as to have poor heat conduction.

前記温度検出部６で検出された雰囲気温度は押出機にフ
ィードバックされて形材の押出速度の制御に利用される
のである。The ambient temperature detected by the temperature detection section 6 is fed back to the extruder and used to control the extrusion speed of the shape.

上記した構成において、前記外気流入防止手段５によっ
てダイス出口側３の空所４への外気の流入を防いだ上で
、この空所４内の空気温度を温度検出部６で検出し、こ
の値を押出機にフィードバックし、形材の押出速度を制
御して等温押出を達成するのでろって、この発明の方法
を採用することによって次に列挙するような利益が斉ら
された。すなわち、 １）押出形材の寸法精度が向上する。In the above configuration, after the outside air inflow prevention means 5 prevents outside air from flowing into the space 4 on the die outlet side 3, the temperature of the air inside this space 4 is detected by the temperature detection unit 6, and this value is detected. is fed back to the extruder and the extrusion speed of the profile is controlled to achieve isothermal extrusion. By adopting the method of the present invention, the following benefits have been achieved. That is, 1) The dimensional accuracy of the extruded shape is improved.

２）押出中のそシ、曲り等の発生が防止でき、矯正工程
の削減が可能となるため、コストダウンとなる。2) The occurrence of warpage, bending, etc. during extrusion can be prevented, and the straightening process can be reduced, resulting in cost reduction.

３）表面状態が均等で、機械的強度が均一な押出形材が
得られる。3) An extruded shape with uniform surface condition and uniform mechanical strength can be obtained.

４）矯正工程が削減されるのできずの発生が少ない。4) Since the straightening process is reduced, there are fewer occurrences of cracks.

【図面の簡単な説明】[Brief explanation of the drawing]

添付図面はこの発明の方法を実施する状況を示す側断面
図である０ なお図において、 １　　　ダイス ２　　　押出形材 ３　　　ダイス出口側 ４　　　　　空　　所 ５　　　外気流入防止手段 ６　　　温度検出部 である。 特許出願人　日本軽金属株式会社The attached drawing is a side sectional view showing a situation in which the method of the present invention is carried out. In the drawing, 1 die 2 extruded section 3 die outlet side 4 space 5 outside air inflow prevention means 6 temperature detection section. Patent applicant Nippon Light Metal Co., Ltd.

Claims (1)

【特許請求の範囲】[Claims] ダイス出口側に外気流入防止手段を設け、この部分の雰
囲気温度を検出し、その検出結果を押出機にフィードバ
ックして押出速度を制御し、もってダイス出口側におけ
る等温押出を達成するようにしたことを特徴とする押出
型材の製造方法。A means for preventing outside air from entering is provided on the die exit side, the ambient temperature in this area is detected, and the detection result is fed back to the extruder to control the extrusion speed, thereby achieving isothermal extrusion on the die exit side. A method for producing an extruded material characterized by: