JPH09291973A - Drive shaft having excellent fatigue characteristic - Google Patents
Drive shaft having excellent fatigue characteristicInfo
- Publication number
- JPH09291973A JPH09291973A JP12626096A JP12626096A JPH09291973A JP H09291973 A JPH09291973 A JP H09291973A JP 12626096 A JP12626096 A JP 12626096A JP 12626096 A JP12626096 A JP 12626096A JP H09291973 A JPH09291973 A JP H09291973A
- Authority
- JP
- Japan
- Prior art keywords
- balance weight
- drive shaft
- memory alloy
- shape memory
- fatigue
- 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.)
- Withdrawn
Links
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- Motor Power Transmission Devices (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、回転駆動力を伝達
する疲労特性に優れた駆動軸、例えば自動車車両のエン
ジン推進力を各車輪に伝えるプロペラシャフト、ドライ
ブシャフトといった部品に関するもので、特に従来品よ
り疲労特性が向上し、サイズダウンによる軽量化が可能
な駆動軸に係る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive shaft for transmitting a rotational driving force and having excellent fatigue characteristics, for example, a propeller shaft and a drive shaft for transmitting engine propulsive force of an automobile vehicle to each wheel, and particularly to a conventional component The present invention relates to a drive shaft that has improved fatigue characteristics and can be made lighter by downsizing.
【０００２】[0002]
【従来の技術】駆動軸は、例えば自動車技術ハンドブッ
ク（第４分冊、生産・品質・整備編ｐ２３３自動車工業
会、１９９１年）に記載されるように、高速回転時に振
動が少ないことが重要な特性のｌつである。その対策と
して、バランスウエイトを取り付け、周方向の重量バラ
ンスを調整した後に使用されることが一般的である。2. Description of the Related Art As described in, for example, the Automotive Engineering Handbook (4th volume, Production / Quality / Maintenance p233 Automobile Manufacturers Association, 1991), it is important that the drive shaft has little vibration at high speed. It is one of As a countermeasure, it is common to attach a balance weight and adjust the weight balance in the circumferential direction before use.
【０００３】このバランスウエイトの取付方法には溶接
が用いられ、自動車等の大量生産を前提とする産業分野
では、溶接の効率や経済性の観点から、スポット溶接あ
るいはプロジエクション溶接といった方法が用いられる
ことが多い。これらの方法によってバランスウエイトを
取り付けた駆動軸を、駆動力を繰返し伝達することに対
応するねじり疲労試験に供すると、図１（ａ）に示すよ
うに鋼管１に溶接されているバランスウエイト２の溶接
部からの疲労割れ５が認められる場合がある。引張強さ
が５００ＭＰａ未満の低強度材の疲労試験の場合は図１
（ｂ）のようにジョイント部品４のジョイント部品接合
部３からの疲労割れ６が特性を決めていたのに対し、特
開平２−１９７５２５号公報に記載されるような材料強
度を高め駆動軸の断面積を減らし、軽量化を進めた場合
の疲労破壊は、図１（ａ）に示すようにバランスウエイ
ト溶接部からの疲労割れ５が支配的となり、ねじり疲労
特性が劣化して軽量化のための大きな障害であった。Welding is used to attach the balance weights. In the industrial field premised on mass production of automobiles, spot welding or projection welding is used from the viewpoint of welding efficiency and economy. It is often done. When the drive shaft to which the balance weight is attached by these methods is subjected to the torsional fatigue test corresponding to the repeated transmission of the driving force, the balance weight 2 welded to the steel pipe 1 as shown in FIG. Fatigue cracks 5 from the weld may be observed. Fig. 1 for fatigue test of low strength material with tensile strength of less than 500 MPa
While the fatigue crack 6 from the joint part joint portion 3 of the joint part 4 determines the characteristics as shown in (b), the material strength is increased and the drive shaft of As shown in Fig. 1 (a), fatigue cracks 5 from the balance weight welds become dominant in the fatigue fracture when the cross-sectional area is reduced and the weight is reduced. Was a major obstacle.
【０００４】バランスウエイト溶接部からの疲労割れの
主な原因としては、溶接部の幾何学形状に起因する応
力集中、溶接時の急熱急冷による金属組織の変化、
溶接残留応力などが考えられる。これらを解消するた
め、例えば、特開平６−２４６４３９、特開平６−２４
６４４０、あるいは特開平６−２４９２９１が開示され
ている。[0004] The main causes of fatigue cracking from a balance weight weld are stress concentration due to the geometrical shape of the weld, changes in the metal structure due to rapid heating and rapid cooling during welding, and the like.
Welding residual stress can be considered. In order to solve these problems, for example, JP-A-6-246439 and JP-A-6-24
6440 or JP-A-6-249291 is disclosed.
【０００５】特開平６−２４６４３９は、取付方法に従
来のスポット溶接やプロジエクション溶接を用いず、ア
ーク溶接を用いてバランスウエイトを取り付けたもので
ある。この方法によるとバランスウエイト取付部の疲労
強度はある程度改善されるが、その場合もバランスウエ
イト取付部から疲労破壊が発生することは避けられず、
完全な対策とはなっていない。In Japanese Patent Laid-Open No. 6-246439, balance weights are attached using arc welding instead of conventional spot welding or projection welding. According to this method, the fatigue strength of the balance weight mounting portion is improved to some extent, but in that case as well, fatigue fracture from the balance weight mounting portion cannot be avoided,
It is not a complete countermeasure.
【０００６】特開平６−２４６４４０は、バランスウエ
イト溶接部を加熱することで疲労特性を向上させるもの
である。バランスウエイト取付部の疲労強度は向上する
が、バランスウエイト溶接部周辺または軸全体を再加熱
する必要があり、特別な設備と工程が要求され、生産性
と経済性に課題がある。Japanese Unexamined Patent Publication No. 6-246440 discloses heating a balance weight weld to improve fatigue characteristics. Although the fatigue strength of the balance weight attachment part is improved, it is necessary to reheat the periphery of the balance weight weld part or the entire shaft, special equipment and process are required, and there are problems in productivity and economy.
【０００７】特開平６−２４９２９１は、バランスウエ
イトの取付けに、溶接による金属接合を用いず、接着接
合を用いてバランスウエイトを取り付けた駆動軸であ
る。これはバランスウエイト取付部の疲労強度低下の原
因である金属接合を排除する点で優れたものであるが、
接着剤の乾燥に時間を要するため、バランスウエイト固
定後の重量バランスの再評価を迅速に行えない点で、生
産性と経済性に課題がある。Japanese Unexamined Patent Publication No. 6-249291 discloses a drive shaft in which the balance weight is attached by using adhesive joining instead of metal joining by welding. This is excellent in eliminating the metal bonding that causes the fatigue strength of the balance weight mounting part to decrease,
Since it takes time to dry the adhesive, it is not possible to quickly re-evaluate the weight balance after fixing the balance weight, and there are problems in productivity and economy.
【０００８】[0008]
【発明が解央しようとする課題】本発明は、このような
現状に鑑み前記課題を解決しようとするもので、バラン
スウエイトを駆動軸に取付ける際に溶接を用いずに固定
することにより、バランスウエイト取付け部の疲労強度
低下を避け、かつ短時間でバランスウエイトを固定でき
生産性と経済性を損なうことのない疲労特性の優れた駆
動軸を提供するものである。SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems in view of such a situation as described above. By fixing the balance weight to the drive shaft without welding, the balance weight is fixed. The purpose of the present invention is to provide a drive shaft having excellent fatigue characteristics, which is capable of fixing the balance weight in a short time while avoiding a decrease in fatigue strength of a weight mounting portion and without impairing productivity and economy.
【０００９】[0009]
【課題を解決するための手段】本発明の要旨は以下の通
りである。The gist of the present invention is as follows.
【００１０】回転振れ回り低減のために駆動軸に取付け
るバランスウエイトを、形状記憶合金で固定したことを
特徴とする、疲労特性に優れた駆動軸。A drive shaft excellent in fatigue characteristics, characterized in that a balance weight attached to the drive shaft for reducing whirling is fixed by a shape memory alloy.
【００１１】[0011]
【発明の実施の形態】本発明の主たる特徴は、駆動軸に
バランスウエイトを固定する際に疲労強度低下の原因と
なる溶接による固定法を用いず、バランスウエイトと駆
動軸の接触部分の疲労強度を駆動軸と同等のものとし
て、さらに形状記憶合金を用いることで、生産性と経済
性を損なうことなくバランスウエイトを目的の位置に固
定し、バランスウエイトの取付部の疲労強度低下を避け
た駆動軸にある。BEST MODE FOR CARRYING OUT THE INVENTION The main feature of the present invention is that when the balance weight is fixed to the drive shaft, the fatigue strength of the contact portion between the balance weight and the drive shaft is eliminated without using a fixing method by welding which causes a decrease in fatigue strength. , Which is equivalent to the drive shaft, and a shape memory alloy is used to fix the balance weight at the target position without sacrificing productivity and economic efficiency, and to avoid a decrease in fatigue strength of the balance weight mounting part. On the axis.
【００１２】次に、本発明を更に詳細に説明する。Next, the present invention will be described in more detail.
【００１３】バランスウエイトの固定には形状記憶合金
を用いる。これにより、疲労強度の低下を引き起こす溶
接を用いずにバランスウエイトの固定が可能となる。A shape memory alloy is used for fixing the balance weight. As a result, the balance weight can be fixed without using welding that causes a decrease in fatigue strength.
【００１４】本発明で形状記憶合金を用いる本質は、形
状記憶合金の形状回復効果によりバランスウエイトを固
定することにある。The essence of using the shape memory alloy in the present invention is to fix the balance weight by the shape recovery effect of the shape memory alloy.
【００１５】形状回復効果によるバランスウエイトの固
定原理を説明するために、一例をあげると、以下のよう
な方法がある。まず、形状記憶合金を駆動軸の外径より
小さい内径を有する円筒状に成形する。これを形状記憶
合金のマルテンサイト変態温度以下の温度で、駆動軸の
外径より大きな内径まで拡径する。この状態で円筒状形
状記憶合金を駆動軸の外部に挿入し、バランスウエイト
取付け部を覆う。その後、形状記憶合金をオーステナイ
ト変態温度以上に加熱して形状回復を起こさせる。これ
により形状記憶合金が収縮し、バランスウエイトが固定
される。なお、ここであげた方法は、形状回復効果によ
るバランスウエイトの固定原理を説明するためにあげた
−例であり、本発明の範囲がこうした製造方法によって
制限を受けるものではない。In order to explain the principle of fixing the balance weight by the shape recovery effect, as an example, there is the following method. First, the shape memory alloy is formed into a cylindrical shape having an inner diameter smaller than the outer diameter of the drive shaft. This is expanded to an inner diameter larger than the outer diameter of the drive shaft at a temperature below the martensitic transformation temperature of the shape memory alloy. In this state, the cylindrical shape memory alloy is inserted outside the drive shaft to cover the balance weight mounting portion. After that, the shape memory alloy is heated above the austenite transformation temperature to cause shape recovery. As a result, the shape memory alloy contracts and the balance weight is fixed. It should be noted that the method described here is an example for explaining the principle of fixing the balance weight by the shape recovery effect-the example is not intended to limit the scope of the present invention by such a manufacturing method.
【００１６】形状記憶合金としては、Ｎｉ−Ｔｉ合金、
Ｃｕ−Ｚｎ−Ａ１合金、Ｆｅ−Ｍｎ−Ｓｉ合金をはじめ
として数十種類の合金が知られているが、本発明では特
に形状記憶合金の種類を限定するものではない。前述の
ように、本発明で形状記憶合金を用いる本質は、形状記
憶合金の形状回復効果によりバランスウエイトを固定す
ることにあり、したがって形状回復効果を示す合金はそ
の種類によらず全て本発明の目的に合致し、本発明の駆
動軸に用いることができる。本発明で用いる形状記憶合
金は駆動軸の使用環境や用途あるいは経済性を考慮して
任意に選択が可能である。As the shape memory alloy, a Ni--Ti alloy,
Although several tens of kinds of alloys such as Cu—Zn—A1 alloy and Fe—Mn—Si alloy are known, the present invention does not limit the kind of shape memory alloy. As described above, the essence of using the shape memory alloy in the present invention is to fix the balance weight by the shape recovery effect of the shape memory alloy. Therefore, all alloys exhibiting the shape recovery effect are independent of the type of the present invention. It fits the purpose and can be used in the drive shaft of the present invention. The shape memory alloy used in the present invention can be arbitrarily selected in consideration of the use environment of the drive shaft, the application, or the economical efficiency.
【００１７】[0017]
【実施例】外径１１４．３ｍｍ、肉厚４．０ｍｍ、引張
強さ７３５ＭＰａクラスの高強度鋼管部分を持つ駆動軸
に、バランスウエイトをＣｕ−Ｚｎ−Ａｌ形状記憶合金
で固定した。Example A balance weight was fixed with a Cu-Zn-Al shape memory alloy to a drive shaft having a high-strength steel pipe part having an outer diameter of 114.3 mm, a wall thickness of 4.0 mm, and a tensile strength of 735 MPa class.
【００１８】Ｃｕ−Ｚｎ−Ａｌ合金は内径ｌｌ３ｍｍ、
肉厚０．８ｍｍ、長さ１００ｍｍの円筒状に成形した後
に、該合金のマルテンサイト変態温度以下の液体窒素温
度で予め内径ｌｌ８ｍｍに拡径したものを用いた。これ
を、駆動軸に挿入してバランスウエイト部を覆い、該合
金のオーステナイト変態温度以上の２００℃に加熱し、
形状回復を起こさせてバランスウエイトを固定した。こ
れら本発明例の駆動軸をねじり疲労試験に供した。The Cu-Zn-Al alloy has an inner diameter of 11 mm,
The alloy was formed into a cylindrical shape having a wall thickness of 0.8 mm and a length of 100 mm, and then expanded to an inner diameter of 11 mm at a liquid nitrogen temperature of the alloy below the martensitic transformation temperature. This is inserted into a drive shaft to cover the balance weight portion and heated to 200 ° C. which is higher than the austenite transformation temperature of the alloy,
The balance weight was fixed by causing shape recovery. The drive shafts of these examples of the present invention were subjected to a torsional fatigue test.
【００１９】比較材として、従来の取付け方法であるプ
ロジェクション溶接を用いてバランスウエイトを取付け
た駆動軸と、バランスウエイトを取付けていない駆動軸
を作製し、これらも同様に試験に供した。As comparative materials, a drive shaft having a balance weight attached thereto and a drive shaft having no balance weight attached thereto were produced by using projection welding, which is a conventional attachment method, and these were similarly subjected to the test.
【００２０】ねじり疲労試験は、完全両振り、負荷トル
ク振幅：７ｋＮｍ、負荷トルク波形：正弦波、周波数：
６Ｈｚで行い、疲労破壊までの繰り返し回数を測定し
た。In the torsional fatigue test, complete double swing, load torque amplitude: 7 kNm, load torque waveform: sine wave, frequency:
It carried out at 6 Hz, and the number of repetitions until fatigue failure was measured.
【００２１】結果を表１および表２に示す。表ｌにはバ
ランスウエイトを取付けていない駆動軸の結果を示す。
バランスウエイトを取付けていない駆動軸の疲労割れは
ジョイント部品接合部より発生し、その破断寿命は平均
で８８８，０５９回であった。一方、表２に示すよう
に、プロジエクション溶接を用いてバランスウエイトを
取付けた比較例６〜１０では、バランスウエイト取付け
部から疲労破壊が発生し、破断寿命が著しく低く、バラ
ンスウエイトを取付けていない駆動軸の場合の平均破断
寿命を１とすると、０．３３程度の破断寿命である。こ
れに対し、形状記憶合金でバランスウエイトを取付けた
本発明例１〜５は、バランスウエイトからの疲労破壊は
発生せず、バランスウエイトを取付けていない駆動軸と
同様に、ジョイント部品接合部において疲労破壊した。
被断寿命もバランスウエイトを取付けていない駆動軸と
同程度であり、本発明によりバランスウエイト取付け部
からの疲労破壊が回避され、バランスウエイトを取付け
ない場合と同等の高い疲労強度が得られることがわか
る。The results are shown in Tables 1 and 2. Table 1 shows the results of the drive shaft without the balance weight attached.
Fatigue cracking of the drive shaft without the balance weight attached occurred at the joint parts of the joint parts, and the rupture life was 888,059 times on average. On the other hand, as shown in Table 2, in Comparative Examples 6 to 10 in which balance weights were attached by using projection welding, fatigue fracture occurred from the balance weight attachment portion, the fracture life was extremely short, and the balance weights were attached. When the average rupture life in the case of a drive shaft having no drive shaft is 1, the rupture life is about 0.33. On the other hand, in the present invention examples 1 to 5 in which the balance weight is attached with the shape memory alloy, the fatigue fracture from the balance weight does not occur, and the fatigue occurs in the joint part joint portion like the drive shaft in which the balance weight is not attached. Destroyed.
The breaking life is about the same as that of the drive shaft without the balance weight attached, and the present invention avoids the fatigue fracture from the balance weight attachment portion, and the high fatigue strength equivalent to that without the balance weight is obtained. Recognize.
【００２２】[0022]
【表１】 [Table 1]
【００２３】[0023]
【表２】 [Table 2]
【００２４】[0024]
【発明の効果】本発明を用いれば、回転振れまわりを低
減するためのバランスウエイトを取り付けた駆動軸にお
いて、ねじり疲労特性を低下させていたバランスウエイ
ト取付部からの疲労破壊発生を回避することができ、部
品としてのねじり疲労特性を向上させることができる。
その結果、実使用応力の上昇が可能であり、駆動軸の軽
量化が可能である。EFFECTS OF THE INVENTION According to the present invention, in a drive shaft equipped with a balance weight for reducing whirling, it is possible to avoid the occurrence of fatigue fracture from the balance weight mounting portion which has deteriorated torsional fatigue characteristics. It is possible to improve the torsional fatigue characteristics of the component.
As a result, the stress in actual use can be increased, and the weight of the drive shaft can be reduced.
【図１】（ａ）、（ｂ）は駆動軸に対して主要な性能評
価であるねじり疲労試験を実施した場合の疲労破壊発生
位量を示す図である。1A and 1B are diagrams showing a fatigue fracture occurrence amount when a torsional fatigue test, which is a main performance evaluation, is performed on a drive shaft.
１ 鋼管 ２ バランスウエイト ３ ジョイント部品接合部 ４ ジョイント部品 ５ バランスウエイト溶接部からの疲労割れ ６ ジョイント部品接合部からの疲労割れ 1 Steel pipe 2 Balance weight 3 Joint part joint 4 Joint part 5 Fatigue crack from balance weight weld 6 Fatigue crack from joint part joint
Claims (1)
けるバランスウエイトを、形状記憶合金で固定したこと
を特徴とする、疲労特性に優れた駆動軸。1. A drive shaft having excellent fatigue characteristics, characterized in that a balance weight attached to the drive shaft for reducing rotational whirling is fixed with a shape memory alloy.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12626096A JPH09291973A (en) | 1996-04-24 | 1996-04-24 | Drive shaft having excellent fatigue characteristic |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12626096A JPH09291973A (en) | 1996-04-24 | 1996-04-24 | Drive shaft having excellent fatigue characteristic |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09291973A true JPH09291973A (en) | 1997-11-11 |
Family
ID=14930788
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12626096A Withdrawn JPH09291973A (en) | 1996-04-24 | 1996-04-24 | Drive shaft having excellent fatigue characteristic |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09291973A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2931870A1 (en) * | 2008-05-29 | 2009-12-04 | Snecma | Rotating piece e.g. turbine shaft, for e.g. jet engine of aircraft, has balancing units comprising ring, where center of gravity of ring is remote from symmetry axle of its internal surface and positioned to compensate unbalance of piece |
| CN105039885A (en) * | 2015-05-05 | 2015-11-11 | 云南电网有限责任公司电力科学研究院 | Anti-fracturing method of circuit breaker operation mechanism on the basis of shape-memory alloy ring |
| GB2545187A (en) * | 2015-12-08 | 2017-06-14 | Bae Systems Plc | Drivetrain |
| CN110783126A (en) * | 2019-11-12 | 2020-02-11 | 苏州国嘉记忆合金有限公司 | Method for strengthening connecting rod of isolating switch based on memory effect of titanium-nickel-based alloy |
-
1996
- 1996-04-24 JP JP12626096A patent/JPH09291973A/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2931870A1 (en) * | 2008-05-29 | 2009-12-04 | Snecma | Rotating piece e.g. turbine shaft, for e.g. jet engine of aircraft, has balancing units comprising ring, where center of gravity of ring is remote from symmetry axle of its internal surface and positioned to compensate unbalance of piece |
| CN105039885A (en) * | 2015-05-05 | 2015-11-11 | 云南电网有限责任公司电力科学研究院 | Anti-fracturing method of circuit breaker operation mechanism on the basis of shape-memory alloy ring |
| CN105039885B (en) * | 2015-05-05 | 2017-01-18 | 云南电网有限责任公司电力科学研究院 | Anti-fracturing method of circuit breaker operation mechanism on the basis of shape-memory alloy ring |
| GB2545187A (en) * | 2015-12-08 | 2017-06-14 | Bae Systems Plc | Drivetrain |
| CN110783126A (en) * | 2019-11-12 | 2020-02-11 | 苏州国嘉记忆合金有限公司 | Method for strengthening connecting rod of isolating switch based on memory effect of titanium-nickel-based alloy |
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