JP2004309221A - Service life evaluation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a service life evaluation device capable of evaluating accurately the service life of a reduction gear or grease, even if a temperature condition is unknown. <P>SOLUTION: This device is constituted to evaluate the service life of the grease from the state quantity of the reduction gear operated by a state quantity operation part 4 in consideration of the grease temperature estimated by a temperature estimation part 5. The device is also constituted so as to identify the friction coefficient of the reduction gear from the state quantity of a motor, and to estimate the temperature from the friction coefficient. Hereby, the service life of the grease can be evaluated accurately without adding a temperature sensor or the like, even if the temperature condition is unknown or the temperature condition is changed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００３３】
また、評価用データ演算部６は、下記のようにして、第ｋサンプル目の平均回転数Ｎａｖ（ｋ）を演算する。
Ｎａｖａ（ｋ）＝Ｆｒａｖｂ（ｋ） （１０）
Ｎａｖｂ（ｋ）＝ｔ（１）＋ｔ（２）＋・・・＋ｔ（ｋ） （１１）
Ｎａｖ（ｋ）＝Ｎａｖａ（ｋ）／Ｎａｖｂ（ｋ） （１２）
次に、動等価ラジアル荷重Ｐ（ｋ）を下記のようにして演算する。
Ｐ（ｋ）＝Ｘ×Ｆｒａｖ（ｋ）＋Ｙ×Ｆａａｖ（ｋ） （１３）
ここで、Ｘはラジアル荷重係数、Ｙはアキシャル荷重係数である。
評価用データ保存部７は、Ｆｒａｖａ（ｋ），Ｆｒａｖｂ（ｋ），Ｆａａｖａ（ｋ），Ｆａａｖｂ（ｋ），Ｎａｖａ（ｋ），Ｎａｖｂ（ｋ）を保存する。
【００３４】
現在寿命評価部８は、評価用データ演算部６により演算された動等価ラジアル荷重Ｐ（ｋ）と平均回転数Ｎａｖ（ｋ）から比較値Ｌ（ｋ）を計算する。ただし、Ｐ_０は基本動定格荷重である。
Ｌ（ｋ）＝１０^６×（Ｐ_０／Ｐ（ｋ））^ｃ／６０／Ｎａｖ（ｋ） （１４）
現在寿命評価部８は、比較値Ｌ（ｋ）に対するＮａｖｂ（ｋ）の比Ｚ＝Ｎａｖｂ（ｋ）／Ｌ（ｋ）を演算し、その比Ｚが規定値を上回っている場合には、規定値以上の軸の軸受交換を促すメッセージをメカニカルシステムの制御盤に表示する。
【００３５】
以上で明らかなように、この実施の形態７によれば、温度推定部５により推定された減速機の温度を考慮して、状態量演算部４により演算された減速機の状態量から減速機の軸受の寿命を評価するように構成したので、温度条件が分からない場合や温度条件が変化する場合でも、正確に軸受の寿命を評価することができる効果を奏する。
また、この実施の形態７によれば、モータの状態量から減速機の摩擦係数を同定し、その摩擦係数から温度を推定するように構成したので、温度センサ等を付加することなく、軸受の現在温度を推定することができる効果を奏する。
【００３６】
実施の形態８．
上記実施の形態１では、温度推定部５がモータの状態量から減速機の摩擦係数を同定して、その摩擦係数からグリースの現在温度を推定するものについて示したが、次のようにしてグリースの現在温度を推定するようにしてもよい。ただし、装置構成は図１と同じである。
即ち、温度推定部５は、予め様々な動作条件でモータと減速機が組み合わされた駆動ユニットを動作させることにより、モータの平均負荷トルク、平均速度と減速機の平均負荷トルク、平均速度とグリース温度上昇の関係を示すデータベースをあらかじめ作成する。
【００３７】
次に温度推定部５は、環境温度Ｔ_１を設定し、メカニカルシステムの実作業が行われると、モータ制御部３から出力される各軸のモータ電流、モータ速度、モータ位置を入力し、その入力データに基づいて、各軸のモータトルクτｍ（ｋ）、モータ速度ｖｍ（ｋ）、減速機トルクτｇ（ｋ）、減速機速度ｖｇ（ｋ）を算出する。
次に温度推定部５は、各軸のモータトルクτｍ（ｋ）、モータ速度ｖｍ（ｋ）、減速機トルクτｇ（ｋ）、減速機速度ｖｇ（ｋ）から、モータの平均負荷トルクＴｍ（ｋ）、平均速度Ｖｍ（ｋ）、減速機の平均負荷トルクＴｇ（ｋ）、平均速度Ｖｂ（ｋ）を算出する。
【００３８】
そして、そのモータの平均負荷トルクＴｍ（ｋ）、平均速度Ｖｍ（ｋ）、減速機の平均負荷トルクＴｇ（ｋ）、平均速度Ｖｂ（ｋ）に最も近い組み合わせをデータベースから抽出し、その温度上昇値をＴ_２とする。データベースから求めた温度上昇値Ｔ_２と環境温度Ｔ_１の和をグリース温度の推定値として評価用データ演算部６に出力する。
この実施の形態８によれば、上記実施の形態１と同様に、温度センサ等を付加することなく、グリースの現在温度を推定することができる効果を奏する。
【００３９】
実施の形態９．
上記実施の形態８では、温度推定部５以外の動作は上記実施の形態１と同様であるものについて示したが、温度推定部５の動作は上記実施の形態８と同様であって、状態量演算部４、評価用データ演算部６、評価用データ保存部７及び現在寿命評価部８の動作は上記実施の形態７と同様であってもよい。
この場合は、上記実施の形態７と同様の効果を奏することができる。
【００４０】
実施の形態１０．
図３はこの発明の実施の形態１０による寿命評価装置を示す構成図であり、図において、図１と同一符号は同一または相当部分を示すので説明を省略する。
温度推定部１１はモータ制御部３からモータの状態量を入力する代わりに、指令値生成部２から指令値を入力し、その指令値からモータの状態量を特定する。なお、温度推定部１１は温度推定手段を構成している。
【００４１】
この実施の形態１０では、予め様々な動作条件でモータと減速機が組み合わされた駆動ユニットを動作させることにより、モータの平均負荷トルク、平均速度と減速機の平均負荷トルク、平均速度と軸受温度の関係を示すデータベースをあらかじめ作成する。
また、様々な動作条件で動作させたときのクーロン摩擦係数と粘性摩擦係数の測定も実施し、軸受温度とクーロン摩擦係数及び粘性摩擦係数の関係を示すデータベースもあらかじめ作成し、環境温度Ｔ_１を設定する。
【００４２】
温度推定部１１は、メカニカルシステムの実作業が行われると、指令値生成部２から各軸の位置指令と速度指令を入力する。次に、モータ制御部３を近似的に表現するモデルを用いて、各軸の位置指令と速度指令から各軸の位置と速度の推定値を計算する。
そして、温度推定部１１は、各軸の速度の推定値からモータ速度と減速機速度を算出する。さらに、メカニカルシステムのダイナミクスモデルと粘性摩擦係数及びクーロン摩擦係数を用いて、モータトルクと減速機に作用するトルクを計算する。粘性摩擦係数及びクーロン摩擦係数は１周期前の温度推定値からデータベースを用いて求める。
【００４３】
さらに、温度推定部１１は、そのモータトルク、モータ速度、減速機トルク及び減速機速度から、モータの平均負荷トルク、平均速度と減速機の平均負荷トルク、平均速度を算出する。
そして、そのモータの平均負荷トルク、平均速度と減速機の平均負荷トルク、平均速度の組み合わせに最も近いデータベースの値を温度上昇値Ｔ_２とし、Ｔ_１＋Ｔ_２を軸受温度の推定値として評価用データ演算部６に出力する。
この実施の形態１０によれば、上記実施の形態７と同様に、温度センサ等を付加することなく、軸受の現在温度を推定することができる効果を奏する。
【００４４】
実施の形態１１．
図４はこの発明の実施の形態１１による寿命評価装置を示す構成図であり、図において、図３と同一符号は同一または相当部分を示すので説明を省略する。
短時間動作寿命評価部１２は温度推定部１１により推定された軸受温度と現在寿命評価部８により評価された軸受の寿命を参照して、メカニカルシステムが継続運転を実施したときに軸受の寿命が目標寿命を超えられるか否かを判定する判定手段を構成している。短時間動作寿命評価結果保存部１３は短時間動作寿命評価部１２の評価結果を保存する。
【００４５】
次に動作について説明する。
この実施の形態１１では、プログラム解析部１は短時間寿命評価用のプログラムを２回実行する。まず、１回目の実行時に寿命評価開始指令を処理すると、寿命評価開始指令を温度推定部１１に送信し、寿命評価終了指令を処理すると、寿命評価終了指令を温度推定部１１に送信する。また、２回目の実行時に寿命評価開始指令を処理すると、寿命評価開始指令を短時間動作寿命評価部１２に送信し、寿命評価終了指令を処理すると、寿命評価終了指令を短時間動作寿命評価部１２に送信する。
【００４６】
温度推定部１１は、寿命評価開始指令を受信してから寿命評価終了指令を受信するまでの間、モータの平均負荷トルク、平均速度、減速機の平均負荷トルク及び平均速度を上記実施の形態１０と同様にして計算する。
温度推定部１１は、予めモータの平均負荷トルク、平均速度、減速機の平均負荷トルク、平均速度と軸受温度のデータベースを作成し、データベースの中で、モータの平均負荷トルク、平均速度、減速機の平均負荷トルク、平均速度の組み合わせに最も近いデータベースの温度を短時間動作評価用の温度Ｔｓとして短時間動作寿命評価部１２に出力する。また、上記実施の形態９と同様にして、モータの平均負荷トルク、平均速度、減速機の平均負荷トルク及び平均速度の計算を常時実施し、現在の軸受温度の推定値をデータベースに基いて算出し、評価用データ演算部６に送信する。
【００４７】
短時間動作寿命評価部１２は、プログラム解析部１から寿命評価開始指令を受け取ると、寿命評価開始指令を受け取ったサンプル周期を第１周期として、式（３）〜式（１３）式に基いて動等価ラジアル荷重Ｐ（ｋ）と平均回転数Ｎａｖ（ｋ）を算出し、プログラム解析部１から寿命評価終了指令を受け取るまで継続する。
寿命評価終了指令を受け取ったサンプル周期が第ｊ周期の場合、第ｊ周期の動等価ラジアル荷重Ｐ（ｊ）と平均回転数Ｈａｖ（ｊ）を用いてＬ（ｊ）を算出する。
Ｌ（ｊ）＝１０^６×（Ｐ_０／Ｐ（ｊ））^ｃ／６０／Ｎａｖ（ｊ） （１５）
【００４８】
次に短時間動作寿命評価部１２は、軸受の目標寿命をＬ_０として、現在寿命評価部８から出力される現在までの動作時間Ｎａｖｂ（ｋ）と現在の予測寿命Ｌ（ｋ）から、評価値ｗを算出する。
ｗａ＝（Ｌ_０−Ｎａｖｂ（ｋ））／Ｌ（ｊ） （１６）
ｗｂ＝（Ｌ（ｋ）−Ｎａｖｂ（ｋ））／Ｌ（ｋ） （１７）
ｗ＝ｗａ／ｗｂ （１８）
【００４９】
短時間動作寿命評価部１２は、評価値ｗを算出すると、その評価値ｗを短時間動作寿命評価結果保存部１３に保存する。そして、メカニカルシステムのすべての軸において評価値ｗを算出し、少なくとも１つの軸における評価値ｗが予め規定した値を上回っている場合、速度・加速度などの動作条件の軽減を促すメッセージをメカニカルシステムの制御盤に表示する。
【００５０】
この実施の形態１１によれば、短時間のテスト動作を行うだけで、当該動作を継続した場合に目標寿命を満たすかどうかの判別を、温度条件も考慮して正確に行うことができる効果を奏する。
なお、実施の形態１１では、軸受の寿命が目標寿命を超えられるか否かを判定するものについて示したが、同様の方法によりグリースの寿命が目標寿命を超えられるか否かを判定するようにしてもよい。
【００５１】
実施の形態１２．
上記実施の形態１１では、プログラム解析部１が短時間寿命評価用のプログラムを２回実行するものについて示したが、次のようにしてもよい。
即ち、図５のプログラム解析部１は、温度が安定するまで待つために、予め規定されている時間が経過するまで、寿命評価開始指令及び寿命評価終了指令の処理を実施せず、プログラムの次の行の処理に移行する。また、温度条件推定部５の処理は上記実施の形態１と同一である。
プログラム動作開始後、予め規定されている時間が経過すると、寿命評価開始指令及び寿命評価終了指令がプログラムに記載されている場合に処理を実行する。寿命評価開始指令を処理すると、寿命評価開始指令を短時間動作寿命評価部１２に送信し、寿命評価終了指令を処理すると寿命評価終了指令を短時間動作寿命評価部１２に送信する。
この実施の形態１２でも、短時間のテスト動作を行うだけで、当該動作を継続した場合に目標寿命を満たすかどうかの判別を、温度条件も考慮して正確に行うことができる。
【００５２】
実施の形態１３．
上記実施の形態１１では、短時間動作寿命評価部１２が軸受の目標寿命をＬ_０として、現在寿命評価部８から出力される現在までの動作時間Ｎａｖｂ（ｋ）と現在の予測寿命Ｌ（ｋ）から評価値ｗを算出するものについて示したが、次のようにしてもよい。
【００５３】
即ち、図６の短時間動作寿命評価部１４は、まず、上記実施の形態１１と同様に、式（１７）を用いてＬ（ｊ）を計算する。
次に短時間動作寿命評価部１４は、軸受の目標寿命をＬ_０として、評価値ｗ＝Ｌ（ｊ）／Ｌ_０の計算をメカニカルシステムの全ての軸で実施し、各軸の評価値ｗの値を短時間動作寿命評価結果保存部１３に出力する。
そして、少なくとも１つの軸における評価値ｗが予め規定した値を上回っている場合、速度・加速度などの動作条件の軽減を促すメッセージをメカニカルシステムの制御盤に表示する。
これにより、短時間のテスト動作を行うだけで、当該動作を継続した場合に目標寿命を満たすかどうかの判別を、温度条件も考慮して正確に行うことができる効果を奏する。
【００５４】
実施の形態１４．
上記実施の形態１では、温度推定部５がモータの状態量から減速機の摩擦係数を同定して、その同定したクーロン摩擦係数と粘性摩擦係数からグリースの現在温度を推定するものについて示したが、次のようにしてグリースの現在温度を推定するようにしてもよい。ただし、装置構成は図１と同じである。
【００５５】
即ち、温度推定部５は、様々な動作速度における摩擦力と減速機のグリース温度との関係を示すデータベースを予め作成する。
温度推定部５は、メカニカルシステムの実作業が行われると、モータの状態量から減速機のクーロン摩擦係数と粘性摩擦係数を同定し、また、モータ速度から現在のモータ速度に最も近く、データベースにデータのある速度ｖｄを求める。
次に、温度推定部５は、その同定したクーロン摩擦係数及び粘性摩擦係数と速度ｖｄから、現在のモータ速度に最も近いデータベースの速度における摩擦力Ｆを算出する。そして、その摩擦力Ｆと、その速度におけるデータベースから算出した摩擦力に最も近いデータベース記載の摩擦力Ｆ１，Ｆ２を求める。
【００５６】
温度推定部５は、摩擦力がＦ１，Ｆ２のときの温度をそれぞれＴ１，Ｔ２とし、グリースの現在温度Ｔを次のように算出する。
Ｔ＝Ｔ１＋（Ｔ２−Ｔ１）×（Ｆ−Ｆ１）／（Ｆ２−Ｆ１） （１９）
この実施の形態４によれば、上記実施の形態１と同様に、温度センサ等を付加することなく、グリースの現在温度を推定することができる効果を奏する。
【００５７】
【発明の効果】
以上のように、この発明によれば、温度推定手段により推定された構成部材の温度を考慮して、状態量演算手段により演算された伝達機構の状態量から構成部材の寿命を評価するように構成したので、温度条件が分からない場合や温度条件が変化する場合でも、正確に構成部材の寿命を評価することができる効果がある。
【図面の簡単な説明】
【図１】この発明の実施の形態１による寿命評価装置を示す構成図である。
【図２】この発明の実施の形態５による寿命評価装置を示す構成図である。
【図３】この発明の実施の形態１０による寿命評価装置を示す構成図である。
【図４】この発明の実施の形態１１による寿命評価装置を示す構成図である。
【図５】この発明の実施の形態１２による寿命評価装置を示す構成図である。
【図６】この発明の実施の形態１３による寿命評価装置を示す構成図である。
【符号の説明】
１ プログラム解析部、２ 指令値生成部、３ モータ制御部、４ 状態量演算部（状態量演算手段）、５ 温度推定部（温度推定手段）、６ 評価用データ演算部（寿命評価手段）、７ 評価用データ保存部（寿命評価手段）、８ 現在寿命評価部（寿命評価手段）、９ 温度測定部（温度推定手段）、１０ 温度推定部（温度推定手段）、１１ 温度推定部（温度推定手段）、１２，１４ 短時間動作寿命評価部（判定手段）、１３ 短時間動作寿命評価結果保存部。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to, for example, a transmission mechanism such as a speed reducer, and a life evaluation device that evaluates the life of a lubricant such as grease of the speed reducer.
[0002]
[Prior art]
The conventional life evaluation device calculates the life of the reduction gear and the grease by using the motor torque and the rotation speed commanded to the servo motor for each sampling time (see Patent Document 1 below). .
[0003]
[Patent Document 1]
JP-A-7-124889 (paragraph numbers [0006] to [0008], FIG. 1)
[0004]
[Problems to be solved by the invention]
Since the conventional life evaluation device is configured as described above, the life of the speed reducer and grease can be calculated.However, in calculating the life, the bearing temperature and the grease temperature of the speed reducer are considered. Therefore, there was a problem that the life of the reduction gear and grease could not be accurately calculated.
[0005]
The present invention has been made to solve the above-described problems, and a life evaluation device capable of accurately evaluating the life of a speed reducer or grease even when temperature conditions are unknown or temperature conditions change. The purpose is to obtain.
[0006]
[Means for Solving the Problems]
A life evaluation apparatus according to the present invention evaluates the life of a component from the state quantity of the transmission mechanism calculated by the state quantity calculation means in consideration of the temperature of the component estimated by the temperature estimating means. It is.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described.
Embodiment 1 FIG.
FIG. 1 is a configuration diagram showing a life evaluation apparatus according to a first embodiment of the present invention. In the figure, a program analysis unit 1 analyzes an operation program of a mechanical system, and a command value generation unit 2 analyzes the program analysis unit 1. A command value is generated according to the result. The motor control unit 3 controls the motor according to the command value generated by the command value generation unit 2. That is, the control amount for the motor (for example, the control amount of the motor current and the motor speed) is updated according to the command value generated by the command value generation unit 2, and the current and speed of the motor are controlled.
The state quantity calculating section 4 constitutes a state quantity calculating means for calculating the state quantity of the transmission mechanism for transmitting the driving force of the motor to the mechanical system. For example, it calculates the input speed of the speed reducer as a transmission mechanism and the torque acting on the speed reducer. The temperature estimating unit 5 constitutes temperature estimating means for estimating the current temperature of the grease (component) of the speed reducer based on a state quantity (for example, motor current or motor speed) fed back from the motor to the motor control unit 3. I have. In the first embodiment, the case where the current temperature of the grease is estimated from the state quantity of the motor is described. However, instead of the state quantity, the current temperature may be estimated by a similar method based on the control amount for the motor. it can.
[0008]
The evaluation data calculation unit 6 calculates the rotational speed r of the reduction gear during the current sampling period from the input speed of the reduction gear calculated by the state quantity calculation unit 4.₀, And considering the grease temperature estimated by the temperature estimating unit 5, the rotational speed r₀Is corrected, and the corrected rotational speed r is added to the total rotational speed nr (k-1) up to the previous time to calculate the total rotational speed nr (k) up to the present. The evaluation data storage unit 7 stores the total number of rotations calculated by the evaluation data calculation unit 6. The current life evaluation unit 8 calculates the total number of rotations nr (k) up to the present time calculated by the evaluation data calculation unit 6 and the reference temperature T₀The grease life is evaluated by comparing the total number of rotations on the input side with respect to the grease replacement time when the reduction gear is driven by the above. Note that the evaluation data calculation unit 6, the evaluation data storage unit 7, and the current life evaluation unit 8 constitute a life evaluation unit.
[0009]
Next, the operation will be described.
First, when an operation program of a mechanical system is given, the program analysis unit 1 analyzes the operation program and outputs the analysis result to the command value generation unit 2.
When receiving the analysis result of the operation program from the program analysis unit 1, the command value generation unit 2 generates a command value according to the analysis result.
The motor control unit 3 controls the motor according to the command value generated by the command value generation unit 2. That is, the control amount for the motor (for example, the control amount of the motor current and the motor speed) is updated according to the command value generated by the command value generation unit 2, and the current and speed of the motor are controlled. Thereby, the motor driving force is transmitted to the mechanical system via the speed reducer, and the mechanical system performs a predetermined operation.
[0010]
The state quantity calculator 4 calculates the state quantity of the speed reducer based on the state quantity fed back from the motor to the motor controller 3. For example, the input speed of the reduction gear and the torque acting on the reduction gear are calculated.
For example, when the reduction gear is directly connected to the motor, the motor speed is set as the input speed of the reduction gear, and the motor current × torque constant × reduction ratio is calculated as the torque acting on the reduction gear.
[0011]
The temperature estimating unit 5 estimates the current temperature of the grease of the speed reducer based on the state quantity fed back from the motor to the motor control unit 3.
Specifically, the current temperature of the grease of the speed reducer is estimated as follows.
First, the temperature estimating unit 5 identifies the Coulomb friction coefficient and the viscous friction coefficient from the motor current and the motor speed, which are the state quantities fed back from the motor to the motor control unit 3.
Next, using the Coulomb friction coefficient and the viscous friction coefficient as keys, the current temperature of the grease is acquired from a database in which information relating to the Coulomb friction coefficient, the viscous friction coefficient, and the temperature of the speed reducer is stored. That is, four sets of data (current temperature) close to the Coulomb friction coefficient and the viscous friction coefficient are acquired from the current temperature of the grease stored in the database, and the average value of the four sets of data is the current value of the grease. Estimate temperature.
However, the above database is created in advance by operating a drive unit in which a motor and a speed reducer are combined under various temperature conditions, and calculating a Coulomb friction coefficient and a viscous friction coefficient at each temperature condition. And
[0012]
The evaluation data calculation unit 6 refers to the relationship information between the grease temperature and the total number of revolutions on the input side related to the grease replacement time (the relationship information is, for example, published by the reduction gear maker), and refers to the temperature estimation unit 5. Input-side total number of rotations L related to grease replacement time when the reducer is driven at the current temperature estimated by_gtAsk for.
Next, the evaluation data calculation unit 6 calculates the reference temperature T₀Input-side total number of rotations L related to grease replacement time when the reducer is driven with_gt0(Total input speed L_gt0Is announced by the reducer maker), and the total rotation speed L on the input side is obtained._gt0Input side total rotation speed L_gtTotal rotation ratio X_t= L_gt/ L_gt0Is calculated.
[0013]
Next, the evaluation data calculator 6 calculates the rotational speed r of the speed reducer during the current sampling period from the input speed of the speed reducer calculated by the state quantity calculator 4.₀Is calculated, and the total rotational speed ratio X_t, The rotational speed r of the speed reducer₀Is corrected.
Then, the corrected rotational speed r = r₀/ X_tIs added to the total number of rotations nr (k-1) up to the previous time stored in the evaluation data storage unit 7 to calculate the total number of rotations nr (k) = nr (k-1) + r up to now. . Here, k means the k-th sample period.
The total rotation speed nr (k) up to the present is stored in the evaluation data storage unit 7 for use in the next calculation. However, when grease is replaced, the total number of rotations of the replaced shaft is reset to zero.
[0014]
The current life evaluation unit 8 calculates the total number of rotations nr (k) up to the present time calculated by the evaluation data calculation unit 6 and the reference temperature T₀Input-side total number of rotations L related to grease replacement time when the reducer is driven with_gt0To evaluate the life of the grease.
That is, the input-side total rotational speed L_gt0Y = nr (k) / L_gt0Is calculated, and when the ratio Y exceeds the specified value, a message urging the grease replacement of the corresponding axis is displayed on the control panel of the mechanical system.
[0015]
As is clear from the above, according to the first embodiment, the life of the grease is calculated from the state quantity of the speed reducer calculated by the state quantity calculating section 4 in consideration of the grease temperature estimated by the temperature estimating section 5. Therefore, even when the temperature condition is not known or the temperature condition changes, the grease life can be accurately evaluated.
Further, according to the first embodiment, since the friction coefficient of the speed reducer is identified from the state quantity of the motor and the temperature is estimated from the friction coefficient, the grease can be removed without adding a temperature sensor or the like. This has the effect of estimating the current temperature.
[0016]
Embodiment 2 FIG.
In the first embodiment, the temperature estimating unit 5 identifies the friction coefficient of the speed reducer from the state quantity of the motor, estimates the current temperature of the grease from the friction coefficient, and the current life evaluation unit 8 The number nr (k) and the reference temperature T₀Input-side total number of rotations L related to grease replacement time when the reducer is driven with_gt0Although the evaluation of the grease life is shown by comparing with the above, the estimation of the current temperature of the grease and the evaluation of the life of the grease may be performed as follows.
[0017]
That is, the temperature estimating unit 5 operates the drive unit in which the motor and the speed reducer are combined under various temperature conditions in advance, so that the Coulomb friction coefficient and the viscous friction coefficient at the reference temperature and the Coulomb friction coefficient and the viscous friction coefficient under various temperature conditions are obtained. Find the increment of the viscous friction coefficient.
When the temperature estimating unit 5 receives the increments of the Coulomb friction coefficient and the viscous friction coefficient, the temperature estimating unit 5 has a built-in neural network for outputting the current temperature of the grease, and the Coulomb friction coefficient and the viscous friction under the various temperature conditions previously obtained. Inputting the coefficient increment and learning in advance.
[0018]
Next, after assembling the mechanical system by filling the grease, the temperature estimating unit 5 operates under the condition of the reference temperature to measure the Coulomb friction coefficient and the viscous friction coefficient at the reference temperature of the mechanical system.
Next, when the actual operation of the mechanical system is performed, the temperature estimating unit 5 identifies the Coulomb friction coefficient and the viscous friction coefficient from the motor current and the motor speed output from the motor control unit 3 as in the first embodiment. I do.
The temperature estimating unit 5 compares the Coulomb friction coefficient and the viscous friction coefficient under the reference temperature condition with the Coulomb friction coefficient and the viscous friction coefficient during the actual operation to obtain an increment from the reference temperature. Input to the net to estimate the current temperature of the grease.
[0019]
The evaluation data calculation unit 6 calculates the corrected rotational speed r of the speed reducer and further calculates the average load torque of the speed reducer in the same manner as in the first embodiment.
The average load torque Tav (k) of the k-th sample is calculated as follows.
Tav (k) = (Tava (k) / Tavb (k))^1/3        (1)
Tava (k)
= N (1) × t (1) × | T (1) |³
+ N (2) × t (2) × | T (2) |³
＋ ・ ・ ・ ・
+ N (k) × t (k) × | T (k) |³
Tavb (k)
= N (1) × t (1) + n (2) × t (2) +... + N (k) × t (k)
Here, T (k) is the torque of the reduction gear of the k-th sample, n (k) is the rotation speed of the reduction gear of the k-th sample, and t (k) is the sample time.
[0020]
The evaluation data storage unit 7 stores the total number of rotations nr (k) up to the present time calculated by the evaluation data calculation unit 6, and Tava (k) and Tavb (k). However, when grease is replaced, the total number of rotations of the replaced shaft is reset to zero.
[0021]
The current life evaluation unit 8 compares the average load torque Tav (k) calculated by the evaluation data calculation unit 6 with the rated torque Tr (k) of the reduction gear.
If Tav (k) <Tr (k), the total rotational speed L for comparison is used._gtTo L_gt0And Where L_gt0Is the reference temperature T₀Corresponds to the total number of rotations on the input side according to the grease replacement time when the reduction gear is driven.
If Tav (k) ≧ Tr (k), the total rotational speed L for comparison_gtTo L_gt0× (Tr (k) / Tav (k))³And
The current life evaluation unit 8 calculates the total rotation speed L for comparison._gtOf the total number of rotations nr (k) with respect to Y = nr (k) / L_gtIs calculated, and when the ratio Y exceeds the specified value, a message urging the grease replacement of the corresponding axis is displayed on the control panel of the mechanical system.
As a result, also in the second embodiment, the same effect as in the first embodiment can be obtained.
[0022]
Embodiment 3 FIG.
In the first embodiment, the temperature estimating unit 5 identifies the friction coefficient of the speed reducer from the state quantity of the motor and estimates the current temperature of the grease from the friction coefficient. May be estimated.
That is, the temperature estimating unit 5 operates the drive unit in which the motor and the speed reducer are combined under various temperature conditions in advance, so that the Coulomb friction coefficient and the viscous friction coefficient at the reference temperature and the Coulomb friction coefficient and the viscous friction coefficient under various temperature conditions are obtained. Find the rate of increase of the viscous friction coefficient.
When the rate of increase of the Coulomb friction coefficient and the viscous friction coefficient are input, the temperature estimating unit 5 has a built-in neural network for outputting the current temperature of the grease, and has the Coulomb friction coefficient and the viscosity under the various temperature conditions previously obtained. The rate of increase of the friction coefficient is input and learned in advance.
[0023]
Next, after assembling the mechanical system by filling the grease, the temperature estimating unit 5 operates under the condition of the reference temperature to measure the Coulomb friction coefficient and the viscous friction coefficient at the reference temperature of the mechanical system.
Next, when the actual operation of the mechanical system is performed, the temperature estimating unit 5 identifies the Coulomb friction coefficient and the viscous friction coefficient from the motor current and the motor speed output from the motor control unit 3 as in the first embodiment. I do.
Then, the temperature estimating unit 5 compares the Coulomb friction coefficient and the viscous friction coefficient under the reference temperature condition with the Coulomb friction coefficient and the viscous friction coefficient during the actual operation to determine the rate of increase from the reference temperature, and calculates the increase rate. The rate is input to the neural network to estimate the current temperature of the grease.
According to the third embodiment, similarly to the first embodiment, there is an effect that the current temperature of the grease can be estimated without adding a temperature sensor or the like.
[0024]
Embodiment 4 FIG.
In the first embodiment, the temperature estimating unit 5 identifies the friction coefficient of the speed reducer from the state quantity of the motor, and estimates the current temperature of the grease from the friction coefficient. May be estimated.
That is, the temperature estimating unit 5 obtains various temperature conditions (grease temperature tg) and a viscous friction coefficient vc by operating a drive unit in which a motor and a speed reducer are combined under various temperature conditions in advance.
Next, the temperature estimating unit 5 obtains coefficients ka and kb of the following linear relational expression from various grease temperatures tg and the viscous friction coefficient vc.
tg = ka + kb × vc (2)
[0025]
Next, when the actual operation of the mechanical system is performed, the temperature estimating unit 5 identifies the Coulomb friction coefficient and the viscous friction coefficient from the motor current and the motor speed output from the motor control unit 3 as in the first embodiment. I do.
The temperature estimator 5 calculates the current temperature of the grease by substituting the identified viscous friction coefficient into the equation (2).
According to the fourth embodiment, similarly to the first embodiment, an effect is obtained that the current temperature of the grease can be estimated without adding a temperature sensor or the like.
[0026]
Embodiment 5 FIG.
FIG. 2 is a configuration diagram showing a life evaluation apparatus according to Embodiment 5 of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and a description thereof will be omitted.
The temperature measuring unit 9 is a temperature sensor that is attached to the outer surface of the speed reducer and measures the surface temperature of the speed reducer. The temperature estimating unit 10 estimates the current temperature of the grease from the surface temperature of the speed reducer measured by the temperature measuring unit 9. In addition, a temperature estimating unit includes the temperature measuring unit 9 and the temperature estimating unit 10.
[0027]
In the first embodiment, the temperature estimation unit 5 identifies the friction coefficient of the speed reducer from the state quantity of the motor and estimates the current temperature of the grease from the friction coefficient. When the surface temperature ts of the machine is measured, the temperature estimating unit 10 adds the preset surface temperature of the reducer and the temperature difference Δtg of the grease to the surface temperature ts of the reducer to obtain the current grease temperature ts + △ tg. May be estimated.
In this case, although a temperature sensor is required, there is an effect that the estimation process of the temperature estimation unit 5 can be simplified.
[0028]
Embodiment 6 FIG.
In the first embodiment, the temperature estimating unit 5 identifies the friction coefficient of the speed reducer from the state quantity of the motor, and estimates the current temperature of the grease from the friction coefficient. May be estimated. However, the device configuration is the same as in FIG.
That is, the temperature estimating unit 5 operates the drive unit in which the motor and the speed reducer are combined under various operating conditions in advance, so that the temperature measured by the temperature sensor of the servo amplifier that controls the motor and the grease temperature of the speed reducer are calculated. Ask for a relationship.
Then, when the actual operation of the mechanical system is performed, the temperature estimating unit 5 inputs the measured temperature of the temperature sensor of the servo amplifier output from the motor control unit 3 and measures the temperature of the temperature sensor with reference to the above relationship. Identify the grease temperature of the reduction gear corresponding to the temperature.
According to the sixth embodiment, similarly to the first embodiment, there is an effect that the current temperature of grease can be estimated without adding a temperature sensor or the like.
[0029]
Embodiment 7 FIG.
In the first to sixth embodiments, the evaluation of the life of the grease is described. However, the life of the bearing (component) of the reduction gear may be evaluated. However, the device configuration is the same as in FIG.
Specifically, it is as follows.
The state quantity calculation unit 4 calculates the rotational speed n of each shaft, the radial load Fr and the axial load Fa of the bearing of each shaft, from the position and speed of the motor control unit 3 of each shaft of the mechanical system.
[0030]
The evaluation data calculation unit 6 calculates the dynamic equivalent radial load P in consideration of the average output rotation speed Nav and the temperature condition.
That is, when the evaluation data calculation unit 6 inputs the current temperature of the speed reducer estimated by the temperature estimation unit 5 (the current temperature of the speed reducer is estimated by the same method as in the first to sixth embodiments). The current temperature of the speed reducer is regarded as the same as the temperature Tj of the bearing portion, and the life temperature correction coefficient fwt at the bearing temperature Tj is calculated with reference to data provided by the bearing manufacturer.
Next, the evaluation data calculation unit 6 receives the position command and the position measurement value from the motor control unit 3, calculates the acceleration command from the position command, calculates the acceleration from the position measurement value, Calculate the maximum value of each.
Then, according to the ratio between the acceleration command maximum value and the acceleration maximum value, the life load correction coefficient fwk until the next calculation of the acceleration command maximum value and the acceleration maximum value is obtained.
[0031]
Next, the evaluation data calculation unit 6 calculates the average radial load Frav (k) and the average axial load Faav (k) of the k-th sample as described below. Here, Fr (k) is the bearing radial load of the k-th sample, Fa (k) is the bearing axial load of the k-th sample, n (k) is the rotation speed, t (k) is the sample time, and fwt (k) is the life. The temperature correction coefficient fwk (k) is a life load correction coefficient. Here, c is a constant that is “3” for a ball bearing and “10/3” for a roller bearing.
[0032]

[0033]
In addition, the evaluation data calculation unit 6 calculates the average rotation speed Nav (k) of the k-th sample as described below.
Nava (k) = Flavb (k) (10)
Navb (k) = t (1) + t (2) +... + T (k) (11)
Nav (k) = Nava (k) / Navb (k) (12)
Next, the dynamic equivalent radial load P (k) is calculated as follows.
P (k) = X × Flav (k) + Y × Fav (k) (13)
Here, X is a radial load coefficient, and Y is an axial load coefficient.
The evaluation data storage unit 7 stores Frava (k), Fravb (k), Faava (k), Faavb (k), Nava (k), and Navb (k).
[0034]
The current life evaluation unit 8 calculates a comparison value L (k) from the dynamic equivalent radial load P (k) calculated by the evaluation data calculation unit 6 and the average rotation speed Nav (k). Where P₀Is the basic dynamic load rating.
L (k) = 10⁶× (P₀/ P (k))^c/ 60 / Nav (k) (14)
The current life evaluation unit 8 calculates the ratio Z = Navb (k) / L (k) of Navb (k) to the comparison value L (k), and if the ratio Z exceeds the specified value, A message prompting the user to replace bearings of a shaft with a value higher than the value is displayed on the control panel of the mechanical system.
[0035]
As is clear from the above, according to the seventh embodiment, the speed reducer is calculated from the state quantity of the speed reducer calculated by the state quantity calculator 4 in consideration of the temperature of the speed reducer estimated by the temperature estimator 5. Since the configuration is such that the life of the bearing is evaluated, there is an effect that the life of the bearing can be accurately evaluated even when the temperature condition is unknown or the temperature condition changes.
Further, according to the seventh embodiment, since the friction coefficient of the speed reducer is identified from the state quantity of the motor and the temperature is estimated from the friction coefficient, the bearing can be mounted without adding a temperature sensor or the like. This has the effect of estimating the current temperature.
[0036]
Embodiment 8 FIG.
In the first embodiment, the temperature estimating unit 5 identifies the friction coefficient of the speed reducer from the state quantity of the motor, and estimates the current temperature of the grease from the friction coefficient. May be estimated. However, the device configuration is the same as in FIG.
That is, the temperature estimating unit 5 operates the drive unit in which the motor and the speed reducer are combined under various operating conditions in advance, so that the average load torque of the motor, the average speed and the average load torque of the speed reducer, the average speed and the grease A database showing the relationship of temperature rise is created in advance.
[0037]
Next, the temperature estimating unit 5 calculates the environmental temperature T₁When the actual operation of the mechanical system is performed, the motor current, motor speed, and motor position of each axis output from the motor control unit 3 are input, and the motor torque τm of each axis is input based on the input data. (K), the motor speed vm (k), the reduction gear torque τg (k), and the reduction gear speed vg (k) are calculated.
Next, the temperature estimating unit 5 calculates the average motor load torque Tm (k) from the motor torque τm (k), motor speed vm (k), reduction gear torque τg (k), and reduction gear speed vg (k) of each axis. ), Average speed Vm (k), average load torque Tg (k) of reducer, and average speed Vb (k).
[0038]
Then, a combination closest to the average load torque Tm (k), the average speed Vm (k), the average load torque Tg (k), and the average speed Vb (k) of the motor is extracted from the database, and the temperature rise thereof is performed. Value T₂And Temperature rise value T obtained from database₂And ambient temperature T₁Is output to the evaluation data calculation unit 6 as an estimated value of the grease temperature.
According to the eighth embodiment, similarly to the first embodiment, there is an effect that the current temperature of grease can be estimated without adding a temperature sensor or the like.
[0039]
Embodiment 9 FIG.
In the eighth embodiment, the operation other than the temperature estimating unit 5 is the same as that of the first embodiment. However, the operation of the temperature estimating unit 5 is the same as that of the eighth embodiment, The operations of the operation unit 4, the evaluation data operation unit 6, the evaluation data storage unit 7, and the current life evaluation unit 8 may be the same as those in the seventh embodiment.
In this case, the same effect as in the seventh embodiment can be obtained.
[0040]
Embodiment 10 FIG.
FIG. 3 is a configuration diagram showing a life evaluation apparatus according to Embodiment 10 of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and a description thereof will be omitted.
The temperature estimating unit 11 inputs a command value from the command value generating unit 2 instead of inputting a motor state quantity from the motor control unit 3, and specifies a motor state quantity from the command value. The temperature estimating unit 11 constitutes a temperature estimating unit.
[0041]
In the tenth embodiment, the average load torque of the motor, the average speed and the average load torque of the reducer, the average speed and the bearing temperature are obtained by operating the drive unit in which the motor and the reducer are combined under various operating conditions in advance. Create a database showing the relationship in advance.
In addition, the Coulomb friction coefficient and the viscous friction coefficient when operating under various operating conditions were measured, and a database showing the relationship between the bearing temperature and the Coulomb friction coefficient and the viscous friction coefficient was created in advance.₁Set.
[0042]
When the actual operation of the mechanical system is performed, the temperature estimating unit 11 inputs a position command and a speed command of each axis from the command value generating unit 2. Next, an estimated value of the position and speed of each axis is calculated from the position command and speed command of each axis using a model that approximately represents the motor control unit 3.
Then, the temperature estimating unit 11 calculates the motor speed and the speed reducer speed from the estimated value of the speed of each axis. Further, using the dynamics model of the mechanical system, the viscous friction coefficient and the Coulomb friction coefficient, the motor torque and the torque acting on the speed reducer are calculated. The viscous friction coefficient and the Coulomb friction coefficient are obtained from the temperature estimation value one cycle before using a database.
[0043]
Further, the temperature estimating unit 11 calculates an average load torque of the motor, an average speed, an average load torque of the reducer, and an average speed from the motor torque, the motor speed, the reducer torque, and the reducer speed.
Then, the value of the database closest to the combination of the average load torque, the average speed of the motor, the average load torque of the speed reducer, and the average speed is calculated as the temperature rise value T.₂And T₁+ T₂Is output to the evaluation data calculation unit 6 as an estimated value of the bearing temperature.
According to the tenth embodiment, similarly to the seventh embodiment, there is an effect that the current temperature of the bearing can be estimated without adding a temperature sensor or the like.
[0044]
Embodiment 11 FIG.
FIG. 4 is a configuration diagram showing a life evaluation apparatus according to Embodiment 11 of the present invention. In the figure, the same reference numerals as those in FIG. 3 denote the same or corresponding parts, and a description thereof will be omitted.
The short-term operation life evaluation unit 12 refers to the bearing temperature estimated by the temperature estimation unit 11 and the life of the bearing evaluated by the current life evaluation unit 8, and determines the life of the bearing when the mechanical system performs continuous operation. The determination means determines whether or not the target life can be exceeded. The short operation life evaluation result storage unit 13 stores the evaluation result of the short operation life evaluation unit 12.
[0045]
Next, the operation will be described.
In the eleventh embodiment, the program analysis unit 1 executes the short-life evaluation program twice. First, when the service life evaluation start command is processed at the first execution, the service life evaluation start command is transmitted to the temperature estimating unit 11, and when the service life evaluation end command is processed, the service life evaluation end command is transmitted to the temperature estimating unit 11. When the life evaluation start command is processed at the time of the second execution, the life evaluation start command is transmitted to the short operation life evaluation unit 12, and when the life evaluation end command is processed, the life evaluation end command is transmitted to the short operation life evaluation unit. 12 is transmitted.
[0046]
The temperature estimating unit 11 calculates the average load torque and the average speed of the motor, the average load torque and the average speed of the speed reducer from the reception of the life evaluation start command to the reception of the life evaluation end command in the tenth embodiment. Calculate in the same way as
The temperature estimating unit 11 creates a database of the average load torque, the average speed of the motor, the average load torque of the speed reducer, the average speed and the bearing temperature in advance, and stores the average load torque, the average speed of the motor, the speed of the speed reducer in the database. The database temperature closest to the combination of the average load torque and the average speed is output to the short-term operation life evaluation unit 12 as the temperature Ts for short-time operation evaluation. In the same manner as in the ninth embodiment, the average load torque and the average speed of the motor, the average load torque and the average speed of the reduction gear are constantly calculated, and the current estimated value of the bearing temperature is calculated based on the database. Then, the data is transmitted to the evaluation data calculation unit 6.
[0047]
Upon receiving the life evaluation start command from the program analysis unit 1, the short-term operation life evaluation unit 12 sets the sample period that has received the life evaluation start command as the first period, based on the equations (3) to (13). The dynamic equivalent radial load P (k) and the average rotation speed Nav (k) are calculated, and the calculation is continued until a life evaluation end command is received from the program analysis unit 1.
When the sample cycle receiving the life evaluation end command is the j-th cycle, L (j) is calculated using the dynamic equivalent radial load P (j) of the j-th cycle and the average rotation speed Hav (j).
L (j) = 10⁶× (P₀/ P (j))^c/ 60 / Nav (j) (15)
[0048]
Next, the short-time operation life evaluation unit 12 sets the target life of the bearing to L₀The evaluation value w is calculated from the current operating time Navb (k) output from the current life evaluation unit 8 and the current predicted life L (k).
wa = (L₀-Navb (k)) / L (j) (16)
wb = (L (k) -Navb (k)) / L (k) (17)
w = wa / wb (18)
[0049]
After calculating the evaluation value w, the short-time operation life evaluation unit 12 stores the evaluation value w in the short-time operation life evaluation result storage unit 13. Then, the evaluation value w is calculated for all axes of the mechanical system, and when the evaluation value w for at least one axis exceeds a predetermined value, a message urging the reduction of operating conditions such as speed and acceleration is sent to the mechanical system. Displayed on the control panel.
[0050]
According to the eleventh embodiment, it is possible to determine whether or not the target life is satisfied when the operation is continued by simply performing the test operation for a short period of time. Play.
Although the eleventh embodiment has been described with reference to the case where it is determined whether or not the life of the bearing exceeds the target life, it is determined in a similar manner whether or not the life of the grease can exceed the target life. You may.
[0051]
Embodiment 12 FIG.
Although the eleventh embodiment has been described with reference to the case where the program analysis unit 1 executes the short-life evaluation program twice, the following may be adopted.
That is, in order to wait until the temperature stabilizes, the program analysis unit 1 in FIG. 5 does not execute the life evaluation start command and the life evaluation end command until a predetermined time elapses. Move to the processing of the row. The processing of the temperature condition estimating unit 5 is the same as that of the first embodiment.
When a predetermined time elapses after the start of the program operation, the process is executed when a life evaluation start command and a life evaluation end command are described in the program. When the life evaluation start command is processed, the life evaluation start command is transmitted to the short-time operation life evaluation unit 12, and when the life evaluation end command is processed, the life evaluation end command is transmitted to the short-time operation life evaluation unit 12.
Also in the twelfth embodiment, it is possible to accurately determine whether or not the target life is satisfied if the operation is continued by performing only a short test operation in consideration of the temperature condition.
[0052]
Embodiment 13 FIG.
In the eleventh embodiment, the short-term operation life evaluation unit 12 sets the target life of the bearing to L.₀Although the calculation of the evaluation value w from the current operating time Navb (k) output from the current life evaluation unit 8 and the current predicted life L (k) has been described, the following may be used.
[0053]
That is, the short-term operation life evaluation unit 14 of FIG. 6 first calculates L (j) using Expression (17), as in the eleventh embodiment.
Next, the short-term operation life evaluation unit 14 sets the target life of the bearing to L₀As an evaluation value w = L (j) / L₀Is calculated for all axes of the mechanical system, and the value of the evaluation value w of each axis is output to the short-term operation life evaluation result storage unit 13.
Then, when the evaluation value w of at least one axis exceeds a predetermined value, a message urging the reduction of operating conditions such as speed and acceleration is displayed on the control panel of the mechanical system.
As a result, there is an effect that it is possible to accurately determine whether or not the target life is satisfied when the operation is continued by performing the test operation for a short time, in consideration of the temperature condition.
[0054]
Embodiment 14 FIG.
In the first embodiment, the temperature estimation unit 5 identifies the friction coefficient of the speed reducer from the state quantity of the motor, and estimates the current temperature of the grease from the identified Coulomb friction coefficient and the viscous friction coefficient. Alternatively, the current temperature of the grease may be estimated as follows. However, the device configuration is the same as in FIG.
[0055]
That is, the temperature estimating unit 5 creates in advance a database indicating the relationship between the frictional force at various operation speeds and the grease temperature of the speed reducer.
When the actual operation of the mechanical system is performed, the temperature estimating unit 5 identifies the Coulomb friction coefficient and the viscous friction coefficient of the speed reducer based on the state quantity of the motor. A speed vd with data is obtained.
Next, the temperature estimating unit 5 calculates the friction force F at the speed of the database closest to the current motor speed from the identified Coulomb friction coefficient and viscous friction coefficient and the speed vd. Then, the frictional force F and the frictional forces F1 and F2 described in the database closest to the frictional force calculated from the database at that speed are obtained.
[0056]
The temperature estimating unit 5 sets the temperatures when the frictional force is F1 and F2 to T1 and T2, respectively, and calculates the current temperature T of the grease as follows.
T = T1 + (T2−T1) × (F−F1) / (F2−F1) (19)
According to the fourth embodiment, similarly to the first embodiment, an effect is obtained that the current temperature of the grease can be estimated without adding a temperature sensor or the like.
[0057]
【The invention's effect】
As described above, according to the present invention, in consideration of the temperature of the component estimated by the temperature estimating means, the life of the component is evaluated from the state quantity of the transmission mechanism calculated by the state quantity calculating means. With the configuration, even when the temperature condition is unknown or the temperature condition changes, there is an effect that the life of the component can be accurately evaluated.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a life evaluation apparatus according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram showing a life evaluation device according to a fifth embodiment of the present invention.
FIG. 3 is a configuration diagram showing a life evaluation device according to a tenth embodiment of the present invention.
FIG. 4 is a configuration diagram showing a life evaluation apparatus according to an eleventh embodiment of the present invention.
FIG. 5 is a configuration diagram showing a life evaluation apparatus according to a twelfth embodiment of the present invention.
FIG. 6 is a configuration diagram showing a life evaluation apparatus according to Embodiment 13 of the present invention.
[Explanation of symbols]
1 program analysis section, 2 command value generation section, 3 motor control section, 4 state quantity calculation section (state quantity calculation section), 5 temperature estimation section (temperature estimation section), 6 evaluation data calculation section (life evaluation section), 7 evaluation data storage unit (life evaluation unit), 8 current life evaluation unit (life evaluation unit), 9 temperature measurement unit (temperature estimation unit), 10 temperature estimation unit (temperature estimation unit), 11 temperature estimation unit (temperature estimation unit) Means), 12, 14 Short-time operation life evaluation section (determination means), 13 Short-time operation life evaluation result storage section.

Claims (4)

State quantity calculating means for calculating the state quantity of the transmission mechanism for transmitting the driving force of the motor to the mechanical system, temperature estimating means for estimating the temperature of the component of the transmission mechanism, and the component estimated by the temperature estimating means And a life evaluating means for evaluating the life of the component from the state quantity of the transmission mechanism calculated by the state quantity calculating means in consideration of the temperature. 2. The life evaluation apparatus according to claim 1, wherein the temperature estimating means identifies a friction coefficient of the transmission mechanism and estimates a temperature of the component from the friction coefficient. 2. The life evaluation apparatus according to claim 1, wherein the temperature estimating means estimates the temperature of the constituent member from a state quantity of the transmission mechanism or the motor or a control quantity for the motor. With reference to the temperature of the component estimated by the temperature estimating means and the life of the component evaluated by the life evaluating means, whether the life of the component exceeds the target life when the mechanical system performs the continuous operation is determined. 2. The life evaluation apparatus according to claim 1, further comprising a judgment unit for judging whether or not the service life has expired.

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