JPS6127133A - Warm forming method of coil spring - Google Patents
Warm forming method of coil springInfo
- Publication number
- JPS6127133A JPS6127133A JP14688484A JP14688484A JPS6127133A JP S6127133 A JPS6127133 A JP S6127133A JP 14688484 A JP14688484 A JP 14688484A JP 14688484 A JP14688484 A JP 14688484A JP S6127133 A JPS6127133 A JP S6127133A
- Authority
- JP
- Japan
- Prior art keywords
- wire
- coil spring
- wire rod
- coil
- warm
- 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.)
- Pending
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21F—WORKING OR PROCESSING OF METAL WIRE
- B21F3/00—Coiling wire into particular forms
- B21F3/02—Coiling wire into particular forms helically
- B21F3/06—Coiling wire into particular forms helically internally on a hollow form
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Wire Processing (AREA)
Abstract
Description
【発明の詳細な説明】
(産業上の利用分野)
本発明は各種機械装置に多用されているコイルばね一就
中大径高強度コイルばねの温間成形方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for warm forming coil springs, particularly large-diameter high-strength coil springs, which are frequently used in various mechanical devices.
(従来の技術)
ばねを製造する場合、通常線径8〜9mm以下の細径線
材からなるコイルばねは素材線材を引抜き加工や熱処理
で所定の強度としたうえで冷間成形してコイルばねとな
し、線径19mm以上の大径線材からなるコイルばねは
成形の困難さから素材線材を熱間でコイルばね形状に成
形のうえ熱処理で所定強度を付与して製品としている。(Prior art) When manufacturing springs, coil springs made of thin wire rods with a wire diameter of 8 to 9 mm or less are usually made by drawing or heat treating the raw wire rods to a predetermined strength, and then cold forming them into coil springs. Coil springs made of large-diameter wire rods with a wire diameter of 19 mm or more are difficult to form, so the wire rods are hot-formed into a coil spring shape and then heat-treated to give a predetermined strength.
しかし乍ら、近来上記大径線材からなるコイルばねも例
えば本出願人の出願発明にかかる特公昭59−1356
8号に開示される如く、素材線材に所定の熱処理を施す
ことにより、引張り強さ150Kgf / m n(以
上でありなから冷間成形性が極めて良好なばね用線材が
開発されて大径高強度線材も冷間成形が可能となった。However, in recent years, coil springs made of the above-mentioned large-diameter wire rods have also been developed, for example, in Japanese Patent Publication No. 59-1356 according to the invention filed by the present applicant.
As disclosed in No. 8, by subjecting the raw material wire to a predetermined heat treatment, a spring wire material with a tensile strength of 150 Kgf/mn (or more) and extremely good cold formability has been developed. It has also become possible to cold form high-strength wire rods.
一方、同じく本出願人の出願発明にかかる特公昭59−
1’0975号に開示される如く、抗張力150Kgf
/mrJ以上としたばね用オイルテンパー線等の線材を
連続的に高周波誘導加熱等の急熱により300〜600
“Cの適当な温度に加熱した状態でコイル成形すること
により、ばね材として具備すべき機械的性質を保持した
まま容易にコイル成形しうるコイルばねの製造方法も開
発された。□
(発明が解決しようとする問題点)
ところで、上記特公昭59−10975号に示される実
施例では、第2図に示す如(、線材コイル(I)から供
給される線材1は、送り込みローラ群2.ワイヤーガイ
ド3およびガイドローラまたはガイドピン4からなるコ
イルばね成形機構(■)に送給される前に例えば高周波
誘導加熱コイル6を備えた温間加熱装置(II)を通過
するようにしているので、温間領域にまで加熱された線
材が通過する上記送り込みローラ群2およびワイヤーガ
イド3を耐熱材で調製せねばならず、また大径高強度線
材の曲げ加工のためには線材1を強力な推力で送給する
必要から送り込みローラ2の圧下刃を大に設定すると、
塑性変形抵抗が低下している線材の真円度を低下させる
などの問題が生ずる虞があった。なお、5として示すの
は線材矯直ローラである。On the other hand, Japanese Patent Publication No. 59-1999, which is also related to the invention filed by the present applicant,
As disclosed in No. 1'0975, tensile strength 150Kgf
/mrJ or more, wire rods such as oil-tempered wires for springs are continuously heated to 300 to 600 by rapid heating such as high-frequency induction heating.
“A method for manufacturing a coil spring has also been developed, which allows coil springs to be easily formed while maintaining the mechanical properties required for a spring material by heating the coil to an appropriate temperature of C. By the way, in the embodiment shown in the above-mentioned Japanese Patent Publication No. 59-10975, as shown in FIG. Before being fed to the coil spring forming mechanism (■) consisting of a guide 3 and guide rollers or guide pins 4, it passes through a warm heating device (II) equipped with, for example, a high frequency induction heating coil 6. The feed roller group 2 and the wire guide 3, through which the wire heated to the warm temperature range passes, must be made of heat-resistant material, and in order to bend the large-diameter high-strength wire, the wire 1 must be subjected to a strong thrust. If you set the reduction blade of feed roller 2 to large because it is necessary to feed the material with
There is a risk that problems such as a decrease in the roundness of the wire rod, which has decreased plastic deformation resistance, may occur. In addition, what is shown as 5 is a wire straightening roller.
(発明の目的)
本発明は上記従来方法に存する問題点を解消する目的で
なされたもので、送り込みローラ群を加熱せずに大径高
強度線材を成形可能とするコイルばね温間成形方法を提
供するものである。(Object of the Invention) The present invention was made with the aim of solving the problems existing in the above-mentioned conventional methods, and provides a coil spring warm forming method that enables forming a large-diameter high-strength wire rod without heating the feed roller group. This is what we provide.
(発明の構成)
本発明の構成は、
(1)連続的に供給される大径高強度ばね用線材を送り
込みローラ、ワイヤーガイドおよびコイリングピンもし
くはコイリングローラからなる成形機構に送り込んで所
定形状のコイルばねに成形する場合において、
(2)当該線材を上記ワイヤーガイド上に存する成形時
の曲げ応力作用点通過直前の送り線上に設けた急速加熱
手段により温間領域まで加熱し、(3)当該温間領域に
加熱された状態の線材を上記コイリングピンもしくはコ
イリングローラにより走行方向の偏向をなさしめてコイ
ル状となすようにした
ことを特徴とするコイルバネの温間成形方法にある。(Structure of the Invention) The structure of the present invention is as follows: (1) Continuously supplied large-diameter high-strength spring wire is fed into a forming mechanism consisting of a feed roller, a wire guide, and a coiling pin or coiling roller to form a coil into a predetermined shape. In the case of forming into a spring, (2) the wire rod is heated to a warm region by a rapid heating means provided on the feed line immediately before passing through the point of bending stress applied during forming on the wire guide; A method for warm forming a coil spring, characterized in that the wire heated in the intermediate region is deflected in the traveling direction by the coiling pin or the coiling roller to form a coil shape.
(実施例)
本発明を第1図(a)および(b)に示す実施例に従っ
て以下に詳述する。(Example) The present invention will be described in detail below according to the example shown in FIGS. 1(a) and 1(b).
第1図(a)および(b)はそれぞれ本発明の要部を示
す正面図およびA−A線断面図であって、成形機構(I
)の送り込みローラ群2の矢印方向への回転力によって
推力Pを与えられた線材1はワイヤーガイド3に設けら
れている線材通路31を通過して、コイリングローラ4
,4方向へ進む。当該ワイヤーガイド3の線材通路31
の出口に近接した点Fとして示す位置には、上記コイリ
ングローラ4,4によってその走行方向を偏向させられ
て塑性加工される際に線材に生ずる曲げ応力作用点があ
るが、本発明では当該曲げ応力作用点Fよりも線材送り
方向後方に、線材通路31を含む所定形状の空間32を
孔設し、当該空間に線材径よりも巻回内径が所定だけ大
径の誘導加熱コイル6を線材通路31と同心状に配置し
、かつその外周を絶縁性磁性体7で上記空間31を埋め
る如くにして構成した急速“加熱手段が設けられている
。上記誘導加熱コイル6は所定周波数・出力電源Eに接
続されており“、当該誘導加熱コイル6内を所定送り速
度で通過する線材を所定の温間領域まで誘導加熱可能に
設定されている。上記温間領域は、線材の強度を低下せ
しめない温度でなければならず、もし線材が焼入れ・焼
戻し線材である場合には、焼戻し温度以下の温度−・−
例えば300〜600℃の範囲でなければならない。上
記絶縁性磁性体7は例えばフェライトコア等からなり、
誘導加熱コイル6から発生する磁束を収束して加熱効率
を高めるとともに、ワイヤ−ガイド3自体およびその周
囲を加熱せしめないために設けられる。FIGS. 1(a) and 1(b) are a front view and a sectional view taken along the line A-A of the present invention, respectively, showing the forming mechanism (I).
) The wire rod 1 is given a thrust P by the rotational force of the feed roller group 2 in the direction of the arrow, passes through the wire rod passage 31 provided in the wire guide 3, and then passes through the coiling roller 4.
, moving in four directions. Wire passage 31 of the wire guide 3
At a position shown as point F near the exit of the coiling rollers 4, there is a bending stress application point that occurs in the wire when the wire is plastically worked by deflecting its running direction by the coiling rollers 4, 4. A space 32 of a predetermined shape including a wire passage 31 is provided behind the stress application point F in the wire feeding direction, and an induction heating coil 6 whose winding inner diameter is larger than the wire diameter by a predetermined value is inserted into the space through the wire passage. A rapid "heating means" is provided which is arranged concentrically with 31 and whose outer periphery is constructed so as to fill the space 31 with an insulating magnetic material 7.The induction heating coil 6 is connected to a predetermined frequency and output power source E. The wire is connected to the induction heating coil 6 at a predetermined feed rate and is set to be able to be inductively heated to a predetermined warm region. The above-mentioned warm region must be at a temperature that does not reduce the strength of the wire, and if the wire is a hardened and tempered wire, the temperature is below the tempering temperature.
For example, it must be in the range of 300 to 600°C. The insulating magnetic body 7 is made of, for example, a ferrite core,
It is provided to converge the magnetic flux generated from the induction heating coil 6 to increase heating efficiency, and to prevent the wire guide 3 itself and its surroundings from being heated.
(発明の作用)
以上のように設定することにより、送り込みローラ群2
により強力な推力Pをもって送給される線材は当該送り
込みローラ群2通過時には常温状態にあって塑性変形抵
抗の低下はなく、他方コイリング時にはワイヤ−ガイド
30線材通路31上にある曲げ応力作用点Fの直前に設
けられている加熱手段によって温間領域にまで加熱され
て塑性変形抵抗が低下しているので、ガイドローラ4・
4に衝接してその走行方向を偏向せしめられる際の曲げ
応力作用点Fに作用する力も小となる。(Operation of the invention) By setting as described above, the feed roller group 2
The wire rod fed with a stronger thrust P is at room temperature when it passes through the feeding roller group 2, and there is no decrease in plastic deformation resistance.On the other hand, during coiling, the bending stress application point F is on the wire guide 30 and the wire rod passage 31. Since the guide roller 4 is heated to a warm region by the heating means provided immediately before the guide roller 4, the plastic deformation resistance is reduced.
The force acting on the bending stress application point F when it collides with 4 and deflects its traveling direction also becomes small.
(実験例)
本発明者は本発明の効果を確認するため次の実験を行っ
た。(Experimental Example) The inventor conducted the following experiment to confirm the effects of the present invention.
◎実験方法
以下に示す供試体を使用して後記条件に従いコイルばね
に成形し、成形時のワイヤーガイド3の昇温状態の観察
と形成されたコイルばねの性能を試験した。◎ Experimental Method The specimens shown below were molded into coil springs according to the conditions described below, and the temperature rise state of the wire guide 3 during molding was observed and the performance of the formed coil springs was tested.
供試体;線材材質−3iCr鋼
線 径−φ14mm
強 度−1,80〜195Kgf/mm(焼入れ・
焼戻し線材
成形機諸元;トルク−60Kgm
送り込み速度−28m/min
高周波電力;周波数−100’KHz
出力・−150Kw
加熱温度;350〜370℃
コイルばね形状;巻径−φ84mm
巻数−8N を
高さ一440mm
◎ワイヤーガイド観察
ワイヤーガイド3の誘導加熱コイル6が設けられている
周辺には殆ど昇温か認められず、その送り方向前方−即
ち出口近傍には300°C程度の昇温かみとめられた。Specimen: Wire material: 3iCr steel wire Diameter: φ14mm Strength: 1,80 to 195Kgf/mm (quenched/
Tempered wire forming machine specifications: Torque: 60 Kgm Feed speed: 28 m/min High frequency power: Frequency: 100'KHz Output: -150 Kw Heating temperature: 350 to 370°C Coil spring shape: Winding diameter: φ84 mm Number of turns: 8 N 440 mm ◎ Wire Guide Observation Almost no temperature increase was observed in the vicinity of the wire guide 3 where the induction heating coil 6 was provided, and a temperature increase of approximately 300°C was observed in the front of the wire guide 3 in the feeding direction, that is, near the exit.
◎耐へたり性試験
試験条件をせん断応力115Kg f /mrd (修
正係数を含む)2時間100hrとして定歪締め付は試
験を行い、同一供試体線材を冷間成形によって同一形状
のコイルばねとしたものの当該試験結果と比較した。◎Settling resistance test The constant strain tightening test was conducted under the conditions of shear stress of 115Kg f /mrd (including correction coefficient) for 2 hours and 100hr, and the same specimen wire was made into a coil spring of the same shape by cold forming. The results were compared with those of the same test.
本発明供試体の永久歪−−−−−2、OX 10−’冷
間成形供試体の永久歪−2,8X 10−P以上の実験
結果から、ワイヤーガイド3に装着された誘導加熱コイ
ル6は、その周囲を絶縁性磁性体7で被覆されているの
でワイヤーガイド3を加熱することなく、また線材走行
時のみ急速加熱手段が動作するようにしているので、そ
の出口近傍の昇温も比較的低く押られることが確認され
るとともに、成形されたコイルばねは特公昭59−10
975号に開示された技術と同様に冷間塑性加工による
コイルばね以上の性能を有することが確認された。Permanent deformation of the specimen of the present invention---2, OX 10-'Permanent deformation of the cold-formed specimen-2,8 Since the wire guide 3 is covered with an insulating magnetic material 7, the wire guide 3 is not heated, and the rapid heating means operates only when the wire is running, so the temperature rise near the outlet is also compared. It was confirmed that the coil spring could be pressed as low as possible, and the molded coil spring was
Similar to the technique disclosed in No. 975, it was confirmed that the coil spring had better performance than the coil spring produced by cold plastic working.
(発明の効果)
本発明を実施することにより、
(1)大径高強度ばね用線材は真円度を保証されつつ極
めて容易にコイル成形可能となり、(2)しかも温間成
形であるので成形後の残留歪が少ない点1強度低下をき
たさない点、線材にスケールを住じない点、脱炭の虞が
ない点9表面粗さに変化を生じない点は勿論のこと、ホ
ットストレッチングと称するものの効果と同様に耐クリ
ープ性および耐疲労性向上等すべて前記特公昭59−1
0975号に示される発明の効果と同等またはそれ以上
の効果が得られるのは勿論のこと、(3)線材送り込み
用ローラ群は耐熱材で調製する必要もなく、
(4)ワイヤーガイドは誘導加熱コイルを包蔵している
にも拘わらず漏洩磁束が殆どなく、また所定温間領域ま
で加熱さ゛れた線材と接触するのは当該ワイヤーガイド
の曲げ応力作用点より前方先端部のみであって、しかも
当該曲げ応力作用点に作用する力は線材の弾性限が低く
なって作用応力が低下しているので、ワイヤーガイドに
はガイド疵がつきにくり、従って損耗がないので耐用時
間が延長されることとなる
などその璽される効果は甚大である。(Effects of the Invention) By carrying out the present invention, (1) large-diameter, high-strength spring wire rods can be formed into coils with guaranteed roundness, and (2) since they are warm-formed, 1. There is no decrease in strength, no scale is present in the wire, and there is no risk of decarburization. 9. There is no change in surface roughness, and hot stretching As well as the effects of the above-mentioned JP 59-1, creep resistance and fatigue resistance are improved.
Of course, the effect equivalent to or greater than the effect of the invention shown in No. 0975 can be obtained, (3) the roller group for feeding the wire does not need to be made of heat-resistant material, and (4) the wire guide is made of induction heating. Despite containing a coil, there is almost no leakage magnetic flux, and only the tip of the wire guide in front of the bending stress application point comes into contact with the wire heated to a predetermined warm temperature range. The force acting on the bending stress application point is lowered due to the lower elastic limit of the wire rod, so the wire guide is less prone to guide flaws, so there is no wear and tear, and the service life is extended. The effect of the seal is enormous.
第1図(a) は本発明コイルばねの温間成形方法の一
実施例の一部断面正面図、第1図(b)は第1図(a)
におけるA−AIm断面図、第2図は従来方法を示す一
部断面正面である。
1−−m−・−大径高強度ばね用線材
2−・−送り込みローラ ′
3−−−−−−ワイヤーガイド
31−線材送り通路
32−空間
4−・−コイリングピン、コイリングローラ6−−−一
急速加熱手段、誘導加熱コイル7−−−−−一絶縁性磁
性体
F−−−一−−曲げ応力作用点
(III)−m−成形機構FIG. 1(a) is a partially sectional front view of an embodiment of the method for warm forming a coil spring of the present invention, and FIG. 1(b) is a partial front view of FIG. 1(a).
FIG. 2 is a partially sectional front view showing the conventional method. 1--m--Wire rod for large diameter high-strength spring 2--Feeding roller' 3--Wire guide 31-Wire feeding passage 32-Space 4--Coiling pin, coiling roller 6-- -1 Rapid heating means, induction heating coil 7----1 Insulating magnetic material F---1--Bending stress application point (III)-m-Forming mechanism
Claims (1)
みローラ、ワイヤーガイドおよびコイリングピンもしく
はコイリングローラからなる成形機構に送り込んで所定
形状のコイルばねに成形する場合において、当該線材を
上記ワイヤーガイド上に存する成形時の曲げ応力作用点
通過直前の送り線上に設けた急速加熱手段により温間領
域まで加熱し、当該温間領域に加熱された状態の線材を
上記コイリングピンもしくはコイリングローラにより走
行方向の偏向をなさしめてコイル状となすようにしたこ
とを特徴とするコイルバネの温間成形方法。 2)温間領域が線材の強度を低下せしめない温度領域で
あることを特徴とする特許請求の範囲第1項記載のコイ
ルばねの温間成形方法。 3)線材が焼入れ・焼戻し熱処理材である場合の温間領
域が焼戻し温度以下であることを特徴とする特許請求の
範囲第1項記載のコイルばねの温間成形方法。 4)急速加熱手段が上記ワイヤーガイドにおける線材送
り通路上の曲げ応力作用点よりも線材送り方向後方側に
設けた所定形状の空間に、周囲を絶縁性磁性体で被覆さ
れて線材送り通路と同心状に配置された誘導加熱コイル
であることを特徴とする特許請求の範囲第1項記載のコ
イルばねの温間成形方法。 5)急速加熱手段が線材の走行時のみ動作することを特
徴とする特許請求の範囲第1項記載のコイルばねの温間
成形方法。[Claims] 1) In the case where continuously supplied large-diameter high-strength spring wire is fed into a forming mechanism consisting of a feeding roller, a wire guide, and a coiling pin or coiling roller to form a coiled spring of a predetermined shape. , the wire rod is heated to a warm region by a rapid heating means provided on the feed line immediately before passing through the bending stress application point during forming on the wire guide, and the wire rod heated to the warm region is coiled. A method for warm forming a coil spring, characterized by deflecting the running direction using a pin or a coiling roller to form a coil spring. 2) The method for warm forming a coil spring according to claim 1, wherein the warm region is a temperature region that does not reduce the strength of the wire rod. 3) The method for warm forming a coil spring according to claim 1, wherein the warm region is below the tempering temperature when the wire is a quenched/tempered heat-treated material. 4) The rapid heating means is provided in a space of a predetermined shape provided on the rear side in the wire rod feeding direction of the bending stress application point on the wire rod feeding path in the wire guide, the periphery of which is covered with an insulating magnetic material, and is concentric with the wire rod feeding path. 2. The method of warm forming a coil spring according to claim 1, wherein the coil spring is an induction heating coil arranged in a shape. 5) The method for warm forming a coil spring according to claim 1, wherein the rapid heating means operates only when the wire is running.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP14688484A JPS6127133A (en) | 1984-07-17 | 1984-07-17 | Warm forming method of coil spring |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP14688484A JPS6127133A (en) | 1984-07-17 | 1984-07-17 | Warm forming method of coil spring |
Publications (1)
Publication Number | Publication Date |
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JPS6127133A true JPS6127133A (en) | 1986-02-06 |
Family
ID=15417751
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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JP14688484A Pending JPS6127133A (en) | 1984-07-17 | 1984-07-17 | Warm forming method of coil spring |
Country Status (1)
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JP (1) | JPS6127133A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04178233A (en) * | 1990-08-27 | 1992-06-25 | Kawasaki Steel Corp | Method and device for forming helical steel wire |
JPH071065A (en) * | 1992-07-29 | 1995-01-06 | Fried Krupp Ag Hoesch Krupp | Method and device for manufacturing curved coil spring |
US8082769B2 (en) * | 2001-04-13 | 2011-12-27 | Orametrix, Inc. | Robot and method for bending orthodontic archwires and other medical devices |
WO2013021828A1 (en) * | 2011-08-11 | 2013-02-14 | 日本発條株式会社 | Compression coil spring and method for producing same |
EP3127629A4 (en) * | 2014-03-25 | 2017-11-15 | Daewon Kang Up Co., Ltd. | Device for manufacturing hot-rolled coil spring |
KR20180022418A (en) * | 2016-08-24 | 2018-03-06 | 울산대학교 산학협력단 | Residual stress control apparatus for coil spring |
CN110026506A (en) * | 2019-04-25 | 2019-07-19 | 浙江富淳弹簧有限公司 | A kind of spring production process |
-
1984
- 1984-07-17 JP JP14688484A patent/JPS6127133A/en active Pending
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04178233A (en) * | 1990-08-27 | 1992-06-25 | Kawasaki Steel Corp | Method and device for forming helical steel wire |
JPH071065A (en) * | 1992-07-29 | 1995-01-06 | Fried Krupp Ag Hoesch Krupp | Method and device for manufacturing curved coil spring |
US8082769B2 (en) * | 2001-04-13 | 2011-12-27 | Orametrix, Inc. | Robot and method for bending orthodontic archwires and other medical devices |
WO2013021828A1 (en) * | 2011-08-11 | 2013-02-14 | 日本発條株式会社 | Compression coil spring and method for producing same |
US10359090B2 (en) | 2011-08-11 | 2019-07-23 | Nhk Spring Co., Ltd. | Compression coil spring and method for producing same |
EP3127629A4 (en) * | 2014-03-25 | 2017-11-15 | Daewon Kang Up Co., Ltd. | Device for manufacturing hot-rolled coil spring |
KR20180022418A (en) * | 2016-08-24 | 2018-03-06 | 울산대학교 산학협력단 | Residual stress control apparatus for coil spring |
KR101879571B1 (en) * | 2016-08-24 | 2018-07-19 | 울산대학교 산학협력단 | Residual stress control apparatus for coil spring |
CN110026506A (en) * | 2019-04-25 | 2019-07-19 | 浙江富淳弹簧有限公司 | A kind of spring production process |
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