JP7675581B2

JP7675581B2 - Twist processing method, twist processing program, and twist processing machine

Info

Publication number: JP7675581B2
Application number: JP2021115191A
Authority: JP
Inventors: 嵩士湯川; 誠栄山本; 憲則藤瀬
Original assignee: Okuma Corp
Current assignee: Okuma Corp
Priority date: 2021-07-12
Filing date: 2021-07-12
Publication date: 2025-05-13
Anticipated expiration: 2041-07-12
Also published as: JP2023011367A

Description

本開示は、ワークをツイスト加工するためのツイスト加工方法、当該方法を実行するためのツイスト加工プログラム、ツイスト加工機に関するものである。 This disclosure relates to a twist processing method for twisting a workpiece, a twist processing program for executing the method, and a twist processing machine.

ツイスト加工は、棒材や平板等のワーク（素材）を軸線上でねじることで変形させて機械部品や意匠物等を製作する塑性加工である。例えば特許文献１には、ツイスト加工によるクランクシャフトの製造方法が記載されている。クランクシャフトは、素材を鍛造で成形するにあたり製品が複雑形状なために型抜きが困難であることから、特許文献１の製造方法では、型抜き可能な形状で素材を成形した後にツイスト加工によって加工箇所の位相を変化させ完成形状としている。
ツイスト加工は、塑性変形を利用する加工のため、ワークは鋼材などの金属材料が一般的である。従って、必要なねじりトルクが高くなることから、高トルクモータやワークが滑らないためのツイスト型を備えた専用設備を使用する必要がある。 Twisting is a plastic processing method for manufacturing machine parts, decorative objects, etc. by twisting a work (material) such as a bar or a flat plate on an axial line to deform the work. For example, Patent Document 1 describes a method for manufacturing a crankshaft using twisting. Since crankshafts are difficult to stamp out from a die due to the complex shape of the product when the material is forged, the manufacturing method described in Patent Document 1 involves forming the material into a shape that can be stamped out, and then changing the phase of the processed part by twisting to obtain the finished shape.
Since twist processing utilizes plastic deformation, the workpiece is generally made of metal materials such as steel, and therefore requires a high twisting torque, making it necessary to use dedicated equipment equipped with a high-torque motor and a twisting die to prevent the workpiece from slipping.

特許第２９９８０５８号公報Patent No. 2998058

ツイスト加工を工作機械で行う際、素材は鋼材などの金属材料が一般的と考えられるが、その際にねじり変形の負荷トルクが高いため、工作機械の主軸モータトルクではねじりの塑性変形が困難である場合がある。さらにワークのチャッキングでの滑りの発生や変形後の弾性ひずみの解放による戻り量が大きいことから、位相位置決め精度の良いツイスト加工が困難であるといった課題もあった。 When twist processing is performed with a machine tool, the material is generally a metal such as steel, but the load torque of the torsional deformation is high, so plastic deformation of the torsion may be difficult with the spindle motor torque of the machine tool. Furthermore, there are issues such as the difficulty of performing twist processing with good phase positioning accuracy due to the occurrence of slippage when chucking the workpiece and the large return amount caused by the release of elastic strain after deformation.

そこで、本開示は、ねじり変形の負荷トルクを減少させ、位相位置決め精度の良いツイスト加工を行うことができるツイスト加工方法、ツイスト加工プログラム、ツイスト加工機を提供することを目的としたものである。 Therefore, the present disclosure aims to provide a twist processing method, a twist processing program, and a twist processing machine that can reduce the load torque of torsional deformation and perform twist processing with good phase positioning accuracy.

上記目的を達成するために、本開示の第１の構成は、対向する２つの回転軸と、ワークの加熱装置と、各前記回転軸と前記加熱装置とを制御する制御装置とを用いて、ワークにツイスト加工を行う方法であって、
前記２つの回転軸によってワークの両端を保持させて、前記２つの回転軸を同期回転させる第１の同期回転ステップと、
前記２つの回転軸を同期回転させながら前記ワークを前記加熱装置により加熱する加熱ステップと、
前記加熱ステップでの加熱開始から所定の加熱時間の経過後、前記２つの回転軸の回転速度に差を設定することで前記ワークにねじり動作を加えるツイスト加工ステップと、
前記ツイスト加工ステップの終了後、前記２つの回転軸を同期回転させる第２の同期回転ステップと、
前記第２の同期回転ステップの実行中に前記加熱装置による加熱を停止する加熱停止ステップと、
前記加熱装置による加熱の停止後、前記２つの回転軸の同期回転を停止する解除ステップと、
を実行すると共に、
前記ツイスト加工ステップにおけるねじり動作は、各前記回転軸の回転速度をそれぞれ設定し、各前記回転軸の回転速度の差分との積で所望のねじり位相値を得るための所定の加工時間が経過するまで行われることを特徴とする。
本開示の第１の構成の別の態様は、対向する２つの回転軸と、ワークの加熱装置と、各前記回転軸と前記加熱装置とを制御する制御装置とを用いて、ワークにツイスト加工を行う方法であって、
前記２つの回転軸によってワークの両端を保持させて、前記２つの回転軸を同期回転させる第１の同期回転ステップと、
前記２つの回転軸を同期回転させながら前記ワークを前記加熱装置により加熱する加熱ステップと、
前記加熱ステップでの加熱開始から所定の加熱時間の経過後、前記２つの回転軸の回転速度に差を設定することで前記ワークにねじり動作を加えるツイスト加工ステップと、
前記ツイスト加工ステップの終了後、前記２つの回転軸を同期回転させる第２の同期回転ステップと、
前記第２の同期回転ステップの実行中に前記加熱装置による加熱を停止する加熱停止ステップと、
前記加熱装置による加熱の停止後、前記２つの回転軸の同期回転を停止する解除ステップと、
を実行すると共に、
前記ツイスト加工ステップにおけるねじり動作は、各前記回転軸の回転速度をそれぞれ設定し、各前記回転軸の位相差を監視することで所望のねじり位相値が得られるまで行われることを特徴とする。
本開示の第１の構成の別の態様は、上記構成において、前記ツイスト加工ステップでは、ねじり動作の開始直後の各前記回転軸の負荷トルク差と位相差との関係に基づいて前記ワークの弾性域での応力－ひずみ関係を計算し、ねじり動作の終了時の各前記回転軸の負荷トルク差から、前記解除ステップ終了後の弾性ひずみの戻り量を推定し、前記弾性ひずみの戻り量を補償する補償ねじり制御を行うことを特徴とする。
上記目的を達成するために、本開示の第２の構成は、ツイスト加工プログラムであって、対向する２つの回転軸と、ワークの加熱装置と、各前記回転軸と前記加熱装置とを制御する制御装置とを備えたツイスト加工機の前記制御装置に、本開示の第１の構成の何れかに記載のツイスト加工方法を実行させることを特徴とする。
上記目的を達成するために、本開示の第３の構成は、対向する２つの回転軸と、ワークの加熱装置と、各前記回転軸と前記加熱装置とを制御する制御装置とを備えたツイスト加工機であって、
ワークの両端を保持させた状態で、前記２つの回転軸を同期回転させる第１の同期回転手段と、
前記２つの回転軸を同期回転させながら前記ワークを前記加熱装置により加熱する加熱手段と、
前記加熱装置による加熱開始から所定の加熱時間の経過後、前記２つの回転軸の回転速度に差を設定することで前記ワークにねじり動作を加えるツイスト加工手段と、
前記ツイスト加工手段の実行後、前記２つの回転軸を同期回転させる第２の同期回転手段と、
前記第２の同期回転手段の実行中に前記加熱装置による加熱を停止する加熱停止手段と、
前記加熱装置による加熱の停止後、前記２つの回転軸の同期回転を停止する解除手段と、
を備え、
前記ツイスト加工手段におけるねじり動作は、各前記回転軸の回転速度をそれぞれ設定し、各前記回転軸の回転速度の差分との積で所望のねじり位相値を得るための所定の加工時間が経過するまで行われることを特徴とする。
本開示の第３の構成の別の態様は、対向する２つの回転軸と、ワークの加熱装置と、各前記回転軸と前記加熱装置とを制御する制御装置とを備えたツイスト加工機であって、
ワークの両端を保持させた状態で、前記２つの回転軸を同期回転させる第１の同期回転手段と、
前記２つの回転軸を同期回転させながら前記ワークを前記加熱装置により加熱する加熱手段と、
前記加熱装置による加熱開始から所定の加熱時間の経過後、前記２つの回転軸の回転速度に差を設定することで前記ワークにねじり動作を加えるツイスト加工手段と、
前記ツイスト加工手段の実行後、前記２つの回転軸を同期回転させる第２の同期回転手段と、
前記第２の同期回転手段の実行中に前記加熱装置による加熱を停止する加熱停止手段と、
前記加熱装置による加熱の停止後、前記２つの回転軸の同期回転を停止する解除手段と、
を備え、
前記ツイスト加工手段におけるねじり動作は、各前記回転軸の回転速度をそれぞれ設定し、各前記回転軸の位相差を監視することで所望のねじり位相値が得られるまで行われることを特徴とする。
In order to achieve the above object, a first configuration of the present disclosure is a method for performing twist processing on a workpiece using two opposing rotation shafts, a workpiece heating device, and a control device that controls each of the rotation shafts and the heating device, comprising:
a first synchronous rotation step of synchronously rotating the two rotation shafts while holding both ends of a workpiece by the two rotation shafts;
a heating step of heating the workpiece by the heating device while rotating the two rotation shafts synchronously;
a twist processing step of applying a twisting operation to the workpiece by setting a difference between the rotation speeds of the two rotating shafts after a predetermined heating time has elapsed since the start of heating in the heating step;
a second synchronous rotation step of synchronously rotating the two rotating shafts after the twisting step is completed;
a heating stopping step of stopping heating by the heating device during execution of the second synchronous rotation step;
a release step of stopping the synchronous rotation of the two rotating shafts after the heating by the heating device is stopped;
In addition to carrying out the above,
The twisting operation in the twist processing step is characterized in that the rotational speeds of the respective rotating shafts are set, and the twisting operation is performed until a predetermined processing time has elapsed in order to obtain a desired twist phase value by multiplying the rotational speeds of the respective rotating shafts by the difference between the rotational speeds of the respective rotating shafts .
Another aspect of the first configuration of the present disclosure is a method for performing twist processing on a workpiece using two opposing rotation shafts, a workpiece heating device, and a control device that controls each of the rotation shafts and the heating device, comprising:
a first synchronous rotation step of synchronously rotating the two rotation shafts while holding both ends of a workpiece by the two rotation shafts;
a heating step of heating the workpiece by the heating device while rotating the two rotation shafts synchronously;
a twist processing step of applying a twisting operation to the workpiece by setting a difference between the rotation speeds of the two rotating shafts after a predetermined heating time has elapsed since the start of heating in the heating step;
a second synchronous rotation step of synchronously rotating the two rotating shafts after the twisting step is completed;
a heating stopping step of stopping heating by the heating device during execution of the second synchronous rotation step;
a release step of stopping the synchronous rotation of the two rotating shafts after the heating by the heating device is stopped;
In addition to carrying out the above,
The twisting operation in the twist processing step is characterized in that the rotation speed of each of the rotating shafts is set and the phase difference between each of the rotating shafts is monitored, and the twisting operation is performed until a desired twist phase value is obtained .
Another aspect of the first configuration of the present disclosure is characterized in that, in the above configuration, in the twist processing step, the stress-strain relationship in the elastic region of the workpiece is calculated based on the relationship between the load torque difference and phase difference of each of the rotating shafts immediately after the start of the twisting operation, and the amount of return of elastic strain after the release step is estimated from the load torque difference of each of the rotating shafts at the end of the twisting operation, and compensating twist control is performed to compensate for the amount of return of elastic strain.
In order to achieve the above object, a second configuration of the present disclosure is a twist processing program which causes a control device of a twist processing machine having two opposing rotating shafts, a workpiece heating device, and a control device for controlling each of the rotating shafts and the heating device to execute a twist processing method described in any of the first configurations of the present disclosure.
In order to achieve the above object, a third configuration of the present disclosure is a twisting machine including two opposing rotating shafts, a work heating device, and a control device that controls each of the rotating shafts and the heating device,
a first synchronous rotation means for synchronously rotating the two rotary shafts while holding both ends of a workpiece;
A heating means for heating the workpiece by the heating device while rotating the two rotary shafts synchronously;
a twist processing means for applying a twisting action to the workpiece by setting a difference between the rotation speeds of the two rotating shafts after a predetermined heating time has elapsed since the start of heating by the heating device;
a second synchronous rotation means for synchronously rotating the two rotating shafts after the execution of the twist processing means;
a heating stop means for stopping heating by the heating device while the second synchronous rotation means is being executed;
a release means for stopping the synchronous rotation of the two rotating shafts after the heating by the heating device is stopped;
Equipped with
The twisting operation in the twist processing means is characterized in that the rotational speeds of the respective rotating shafts are set, and the twisting operation is performed until a predetermined processing time has elapsed in order to obtain a desired twist phase value by multiplying the rotational speeds of the respective rotating shafts by the difference between the rotational speeds of the respective rotating shafts .
Another aspect of the third configuration of the present disclosure is a twist processing machine including two opposing rotating shafts, a work heating device, and a control device that controls each of the rotating shafts and the heating device,
a first synchronous rotation means for synchronously rotating the two rotary shafts while holding both ends of a workpiece;
A heating means for heating the workpiece by the heating device while rotating the two rotary shafts synchronously;
a twist processing means for applying a twisting action to the workpiece by setting a difference between the rotation speeds of the two rotating shafts after a predetermined heating time has elapsed since the start of heating by the heating device;
a second synchronous rotation means for synchronously rotating the two rotating shafts after the execution of the twist processing means;
a heating stop means for stopping heating by the heating device while the second synchronous rotation means is being executed;
a release means for stopping the synchronous rotation of the two rotating shafts after the heating by the heating device is stopped;
Equipped with
The twisting operation in the twist processing means is characterized in that the rotation speed of each of the rotating shafts is set and the phase difference between the rotating shafts is monitored until a desired twist phase value is obtained .

本開示によれば、回転中に加熱することでワーク全周が軟化すなわち降伏応力が減少し、加工に必要な負荷トルクが減少する。よって、チャッキング滑りの抑制及び弾性ひずみの解放による戻り量の減少が期待でき、位相位置決め精度の良いツイスト加工を行うことができる。 According to the present disclosure, by heating the workpiece during rotation, the entire circumference is softened, i.e., the yield stress is reduced, and the load torque required for processing is reduced. This is expected to suppress chucking slippage and reduce the amount of return due to the release of elastic strain, allowing twist processing with good phase positioning accuracy to be performed.

旋盤におけるツイスト加工の模式図である。FIG. 1 is a schematic diagram of twist processing on a lathe. ツイスト加工方法のフローチャートである。1 is a flowchart of a twisting method. 各主軸の角速度と加熱（レーザ照射）との時間経過を示す説明図である。FIG. 11 is an explanatory diagram showing the angular velocity of each spindle and heating (laser irradiation) over time.

以下、本開示の実施の形態を図面に基づいて説明する。
図１は、ツイスト加工機として旋盤Ｍを用いたツイスト加工の模式図である。図２は、ツイスト加工方法のフローチャートである。図３は、ツイスト加工の時間経過を示す説明図である。
旋盤Ｍは、メイン主軸１と、メイン主軸１と同軸上に配置される対向主軸２とでワーク４の両端を保持可能となっている。ワーク４は横断面円形の棒材である。また、旋盤Ｍは、ワーク４の加熱装置としてレーザユニット３を備えている。
旋盤Ｍの制御装置１０は、記憶部に予め記憶されたツイスト加工プログラムに従って両主軸１，２及びレーザユニット３を制御して、図２のツイスト加工方法を実行する。すなわち、制御装置１０は、両主軸１，２と併せて本開示の第１、第２の同期回転手段、ツイスト加工手段、解除手段を構成し、レーザユニット３と併せて本開示の加熱手段、加熱停止手段を構成する。 Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings.
Fig. 1 is a schematic diagram of a twist processing using a lathe M as a twist processing machine. Fig. 2 is a flow chart of a twist processing method. Fig. 3 is an explanatory diagram showing the time course of a twist processing.
The lathe M is capable of holding both ends of a workpiece 4 between a main spindle 1 and an opposing spindle 2 that is arranged coaxially with the main spindle 1. The workpiece 4 is a bar material having a circular cross section. The lathe M also includes a laser unit 3 as a heating device for the workpiece 4.
The control device 10 of the lathe M controls both spindles 1, 2 and the laser unit 3 in accordance with a twist processing program stored in advance in the storage unit to execute the twist processing method of Fig. 2. That is, the control device 10, together with both spindles 1, 2, constitutes the first and second synchronous rotation means, twist processing means, and release means of the present disclosure, and together with the laser unit 3, constitutes the heating means and heating stop means of the present disclosure.

図２において、まずＳ１で、メイン主軸１と対向主軸２とを、記憶部に予め設定された角速度ω１となるように矢印方向へ同期回転させる（図３のｔ１：第１の同期回転ステップ）。
次に、Ｓ２で、同期回転を保持したまま、レーザユニット３により、レーザをワーク４に照射する（加熱ステップ）。この照射により、ワーク４の加熱範囲５が加熱され軟化する。制御装置１０には、レーザユニット３の出力、ワーク４の加熱位置座標、同期回転中の加熱時間（図３のｔ２～ｔ３）が設定されている。
ここで両主軸１，２を同期回転させてから加熱を加えることで、加熱点が限られた範囲であってもワーク４の全周を確実に加熱することができる。 In FIG. 2, first, in S1, the main spindle 1 and the counter spindle 2 are rotated synchronously in the direction of the arrow so as to rotate at an angular velocity ω1 preset in the storage unit (t1 in FIG. 3: first synchronous rotation step).
Next, in S2, while maintaining the synchronous rotation, the laser unit 3 irradiates the workpiece 4 with a laser (heating step). This irradiation heats and softens the heating range 5 of the workpiece 4. The output of the laser unit 3, the heating position coordinates of the workpiece 4, and the heating time during the synchronous rotation (t2 to t3 in FIG. 3) are set in the control device 10.
Here, by rotating both spindles 1 and 2 synchronously and then applying heat, the entire circumference of the workpiece 4 can be reliably heated even if the heating point is limited in area.

次に、加熱時間経過後、Ｓ３で、ワーク４が冷却しないようレーザ照射を保持した状態で、両主軸１，２の回転を止めないまま一方の主軸の角速度をω２に変化させるねじり動作を行う（図３のｔ３：ツイスト加工ステップ）。同時にＳ３では、ねじり動作開始直後の両主軸１，２の負荷トルク差と位相差とを取得する。これにより、ツイスト加工におけるワーク４の弾性域での応力－ひずみ関係を得ることができる。
ねじり動作は、Ｓ４で、目標ねじり位相値（所望のねじり位相値）であるθが得られる所定の加工時間ｔが経過するまで行われる（図３のｔ３～ｔ４）。以下に関係式を記す。
θ＝（ω１－ω２）×ｔ
例として、ワーク４を左ねじれにする場合は、対向主軸２の角速度をω１＜ω２となるようにω２に変化させる。ワーク４を右ねじれとする場合は、角速度をω１＞ω２となるように変化させる。
但し、ここでは加工時間ｔによらず、両主軸１，２の位相差を監視して目標ねじり位相値θが得られるまでねじり動作を追加するようにしてもよい。 Next, after the heating time has elapsed, in S3, while maintaining the laser irradiation so that the workpiece 4 does not cool, a twisting operation is performed in which the angular velocity of one of the spindles is changed to ω2 without stopping the rotation of both spindles 1 and 2 (t3 in FIG. 3: twisting step). At the same time, in S3, the load torque difference and phase difference of both spindles 1 and 2 immediately after the start of the twisting operation are obtained. This makes it possible to obtain the stress-strain relationship in the elastic region of the workpiece 4 during twisting.
The twisting operation is continued in S4 until a predetermined processing time t has elapsed (t3 to t4 in FIG. 3) at which a target twist phase value (desired twist phase value) θ is obtained.
θ = (ω1 - ω2) × t
For example, when the workpiece 4 is to be twisted to the left, the angular velocity of the counter spindle 2 is changed to ω2 so that ω1<ω2 holds. When the workpiece 4 is to be twisted to the right, the angular velocity is changed to ω1>ω2.
However, here, regardless of the machining time t, the phase difference between both spindles 1 and 2 may be monitored and twisting operations may be added until the target twisting phase value θ is obtained.

Ｓ４で目標ねじり位相値θに達した際、両主軸１，２の負荷トルクに差があると、同期制御が解除されたとき、弾性ひずみの開放により戻りが発生し、位相精度が悪化するおそれがある。そこで、制御装置１０は、Ｓ３で取得した応力－ひずみ関係から、加工時間ｔが経過してＳ４で目標ねじり位相値θに達した時点での両主軸１，２の負荷トルク差を監視する。負荷トルク差があると、応力－ひずみ関係に基づいて本制御終了後の弾性ひずみの戻り量が推定できる。
よって、Ｓ５で、制御装置１０は、両主軸１，２の負荷トルク差から弾性ひずみを推定し、弾性ひずみの戻り量を補償する補償ねじり制御を行う。この補償ねじり制御は、ねじり動作の加工時間ｔを延長するか、或いはさらにねじり動作を加えるかすることで行う。なお、目標ねじり位相値θに達した時点で負荷トルク差がなければＳ５の処理は行わない。 If there is a difference in the load torque between the spindles 1 and 2 when the target torsional phase value θ is reached in S4, the release of elastic strain will cause a return when the synchronous control is released, which may result in a deterioration in phase accuracy. Therefore, the control device 10 monitors the load torque difference between the spindles 1 and 2 from the stress-strain relationship acquired in S3 at the time when the target torsional phase value θ is reached in S4 after the machining time t has elapsed. If there is a load torque difference, the amount of return of elastic strain after the end of this control can be estimated based on the stress-strain relationship.
Therefore, in S5, the control device 10 estimates the elastic strain from the load torque difference between the two spindles 1 and 2, and performs compensatory torsion control to compensate for the return amount of the elastic strain. This compensatory torsion control is performed by extending the processing time t of the torsion operation or by adding an additional torsion operation. Note that if there is no load torque difference when the target torsion phase value θ is reached, the process of S5 is not performed.

次に、Ｓ６で、加工時間ｔの経過後、両主軸１，２の回転を止めないまま角速度の等しい同期回転に戻す（図３のｔ４：第２の同期回転ステップ）。この際、同期回転の角速度は問わない。このようにレーザ照射の停止前に再び同期回転させることで、ワーク４に局所的な加熱が加わらないようにすることができる。
次に、Ｓ７で、レーザユニット３によるレーザ照射を停止する（図３のｔ５：加熱停止ステップ）。
次に、Ｓ８で、両主軸１，２の同期回転を停止し（図３のｔ６）、両主軸１，２の同期制御を解除する（解除ステップ）。このように同期回転とした後に加熱を停止し、両主軸１，２の同期を保持したまま回転を停止することで、ワーク４に余分なねじりトルクが発生することを抑制できる。 Next, in S6, after the processing time t has elapsed, the rotation of both spindles 1 and 2 is returned to synchronous rotation at equal angular velocities without being stopped (t4 in FIG. 3: second synchronous rotation step). At this time, the angular velocity of the synchronous rotation does not matter. By rotating the spindles 1 and 2 synchronously again before stopping the laser irradiation in this way, it is possible to prevent localized heating of the workpiece 4.
Next, in S7, the laser irradiation by the laser unit 3 is stopped (t5 in FIG. 3: heating stop step).
Next, in S8, the synchronous rotation of both spindles 1 and 2 is stopped (t6 in FIG. 3), and the synchronous control of both spindles 1 and 2 is released (release step). By stopping the heating after the synchronous rotation in this manner and stopping the rotation while maintaining the synchronization of both spindles 1 and 2, it is possible to suppress the generation of excess torsional torque in the workpiece 4.

このように、上記形態のツイスト加工方法及び旋盤Ｍでは、対向する両主軸１，２によってワーク４の両端を保持させて、両主軸１，２を同期回転させながらワーク４をレーザユニット３により加熱し、所定の加熱時間の経過後、両主軸１，２の回転速度に差を設定することでワーク４にねじり動作を加える。そして、ねじり動作の終了後、再び両主軸１，２を同期回転させ、その後レーザユニット３による加熱と両主軸１，２の同期回転とを順番に停止させる。
この構成によれば、回転中に加熱することでワーク４の全周が軟化すなわち降伏応力が減少し、加工に必要な負荷トルクが減少する。よって、チャッキング滑りの抑制及び弾性ひずみの解放による戻り量の減少が期待でき、位相位置決め精度の良いツイスト加工を行うことができる。 In this manner, in the twist processing method and lathe M of the above-described form, both ends of the workpiece 4 are held by the opposing spindles 1, 2, and the workpiece 4 is heated by the laser unit 3 while the spindles 1, 2 are rotated synchronously, and after a predetermined heating time has elapsed, a twisting operation is applied to the workpiece 4 by setting a difference in the rotational speeds of the spindles 1, 2. Then, after the twisting operation is completed, the spindles 1, 2 are rotated synchronously again, and then the heating by the laser unit 3 and the synchronous rotation of the spindles 1, 2 are stopped in order.
According to this configuration, the entire circumference of the workpiece 4 is softened by heating during rotation, i.e., the yield stress is reduced, and the load torque required for processing is reduced. Therefore, it is expected that chucking slippage can be suppressed and the return amount can be reduced by releasing elastic strain, and twist processing with good phase positioning accuracy can be performed.

特に、切削加工のできる旋盤Ｍでツイスト加工を行うので、ツイスト加工の終了後に発生するひずみあるいはバリ等を切削で除去可能となる。
また、ねじり動作開始直後のワーク４が弾性域にある状態での両主軸１，２の負荷トルク差と位相差とから、応力とひずみとの関係を取得し、ねじり動作終了時の両主軸１，２の負荷トルク差から、弾性ひずみの戻り量を推定し、当該戻り量を補償する補償ねじり制御を行うので、ワーク４の断面形状や温度依存により同定が困難な弾性係数を考慮することなく、精度の良いツイスト加工が可能となる。 In particular, since the twisting process is carried out on a lathe M capable of cutting, distortion or burrs that occur after the twisting process can be removed by cutting.
In addition, the relationship between stress and strain is obtained from the load torque difference and phase difference between the two spindles 1, 2 when the workpiece 4 is in the elastic region immediately after the start of the twisting operation, and the amount of return of the elastic strain is estimated from the load torque difference between the two spindles 1, 2 when the twisting operation is completed. Compensatory twist control is then performed to compensate for this amount of return, making it possible to perform precise twist processing without taking into account the cross-sectional shape of the workpiece 4 and the elastic coefficient, which is difficult to identify due to its temperature dependence.

なお、上記形態では、加熱装置としてレーザユニットを用いているが、誘導加熱器等の他の装置も採用できる。
また、旋盤を利用してツイスト加工を実行しているが、他の工作機械を利用して差し支えない。よって、ワークの向きは横向きでなく縦向きや斜め向きでもよい。ワークの形状も上記形態に限定されない。
さらに、ツイスト加工機としては、工作機械に限らず、対向する２つの回転軸と、ワークの加熱装置と、各回転軸と加熱装置とを制御する制御装置とを備えたものであれば、他の産業機械も使用可能である。ツイスト加工の専用機であってもよい。 In the above embodiment, a laser unit is used as the heating device, but other devices such as an induction heater can also be used.
In addition, although the twisting process is performed using a lathe, other machine tools may be used. Therefore, the orientation of the workpiece may be vertical or oblique instead of horizontal. The shape of the workpiece is not limited to the above.
Furthermore, the twist processing machine is not limited to a machine tool, and other industrial machines can be used as long as they are equipped with two opposing rotating shafts, a heating device for the workpiece, and a control device for controlling each of the rotating shafts and the heating device. A machine dedicated to twist processing can also be used.

１・・メイン主軸、２・・対向主軸、３・・レーザユニット、４・・ワーク、５・・加熱範囲、１０・・制御装置。 1: Main spindle, 2: Counter spindle, 3: Laser unit, 4: Workpiece, 5: Heating area, 10: Control device.

Claims

A method for performing twist processing on a workpiece using two opposing rotation shafts, a workpiece heating device, and a control device that controls each of the rotation shafts and the heating device, comprising:
a first synchronous rotation step of synchronously rotating the two rotation shafts while holding both ends of a workpiece by the two rotation shafts;
a heating step of heating the workpiece by the heating device while rotating the two rotation shafts synchronously;
a twist processing step of applying a twisting operation to the workpiece by setting a difference between the rotation speeds of the two rotating shafts after a predetermined heating time has elapsed since the start of heating in the heating step;
a second synchronous rotation step of synchronously rotating the two rotating shafts after the twisting step is completed;
a heating stopping step of stopping heating by the heating device during execution of the second synchronous rotation step;
a release step of stopping the synchronous rotation of the two rotating shafts after the heating by the heating device is stopped;
In addition to carrying out the above,
a twisting operation in the twisting step, which is performed until a predetermined processing time has elapsed, the processing time being required to obtain a desired twist phase value by multiplying the rotational speed of each of the rotating shafts by the difference between the rotational speeds of the rotating shafts, the twisting operation being performed until a predetermined processing time has elapsed, the desired twist phase value being obtained by multiplying the rotational speed of each of the rotating shafts by the difference between the rotational speeds of the rotating shafts.

A method for performing twist processing on a workpiece using two opposing rotation shafts, a workpiece heating device, and a control device that controls each of the rotation shafts and the heating device, comprising:
a first synchronous rotation step of synchronously rotating the two rotation shafts while holding both ends of a workpiece by the two rotation shafts;
a heating step of heating the workpiece by the heating device while rotating the two rotation shafts synchronously;
a twist processing step of applying a twisting operation to the workpiece by setting a difference between the rotation speeds of the two rotating shafts after a predetermined heating time has elapsed since the start of heating in the heating step;
a second synchronous rotation step of synchronously rotating the two rotating shafts after the twisting step is completed;
a heating stopping step of stopping heating by the heating device during execution of the second synchronous rotation step;
a release step of stopping the synchronous rotation of the two rotating shafts after the heating by the heating device is stopped;
In addition to carrying out the above,
A twist processing method characterized in that the twisting operation in the twist processing step is performed by respectively setting the rotational speed of each of the rotating shafts and monitoring the phase difference of each of the rotating shafts until a desired twist phase value is obtained .

The twist processing method according to claim 1 or 2, characterized in that in the twist processing step, the stress-strain relationship in the elastic region of the workpiece is calculated based on the relationship between the load torque difference and phase difference of each of the rotating shafts immediately after the start of the twisting operation, the amount of elastic strain recovery after the release step is estimated from the load torque difference of each of the rotating shafts at the end of the twisting operation, and compensating twist control is performed to compensate for the amount of elastic strain recovery.

A twist processing program for causing a control device of a twist processing machine having two opposing rotating shafts, a workpiece heating device, and a control device that controls each of the rotating shafts and the heating device to execute the twist processing method described in any one of claims 1 to 3 .

A twist processing machine including two opposing rotary shafts, a work heating device, and a control device for controlling each of the rotary shafts and the heating device,
a first synchronous rotation means for synchronously rotating the two rotary shafts while holding both ends of a workpiece;
A heating means for heating the workpiece by the heating device while rotating the two rotary shafts synchronously;
a twist processing means for applying a twisting action to the workpiece by setting a difference between the rotation speeds of the two rotating shafts after a predetermined heating time has elapsed since the start of heating by the heating device;
a second synchronous rotation means for synchronously rotating the two rotating shafts after the execution of the twist processing means;
a heating stop means for stopping heating by the heating device while the second synchronous rotation means is being executed;
a release means for stopping the synchronous rotation of the two rotating shafts after the heating by the heating device is stopped;
Equipped with
A twist processing machine characterized in that the twisting operation in the twist processing means is performed until a predetermined processing time has elapsed, in which the rotational speed of each of the rotating shafts is set and a desired twist phase value is obtained by multiplying the rotational speed and the difference between the rotational speeds of each of the rotating shafts.

A twist processing machine including two opposing rotary shafts, a work heating device, and a control device for controlling each of the rotary shafts and the heating device,
a first synchronous rotation means for synchronously rotating the two rotary shafts while holding both ends of a workpiece;
A heating means for heating the workpiece by the heating device while rotating the two rotary shafts synchronously;
a twist processing means for applying a twisting action to the workpiece by setting a difference between the rotation speeds of the two rotating shafts after a predetermined heating time has elapsed since the start of heating by the heating device;
a second synchronous rotation means for synchronously rotating the two rotating shafts after the execution of the twist processing means;
a heating stop means for stopping heating by the heating device while the second synchronous rotation means is being executed;
a release means for stopping the synchronous rotation of the two rotating shafts after the heating by the heating device is stopped;
Equipped with
A twist processing machine characterized in that the twisting operation in the twist processing means is performed by setting the rotational speed of each of the rotating shafts and monitoring the phase difference of each of the rotating shafts until a desired twist phase value is obtained .