JP2020008472A - Temperature evaluation device, life evaluation device, and robot system - Google Patents

Abstract

To estimate the temperature of a component precisely.SOLUTION: A temperature evaluation device 12 is for evaluating the temperature of a component in a transmission mechanism in a machine having a motor and the transmission mechanism for transmitting power of the motor to a movable part. The temperature evaluation device 12 includes: a motor heat generation amount calculation unit 14 for calculating the heat generation amount of a motor on the basis of the current value of the motor; a friction heat generation amount calculation unit 15 for calculating the friction heat generation amount in the transmission mechanism on the basis of the rate of rotation of the motor and the coefficient of friction of the transmission mechanism; and a component temperature estimation unit 17 for estimating the temperature of the component other than a lubricant for lubricating the component, on the basis of the calculated friction heat generation amount and the motor heat generation amount.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a temperature estimation device, a life evaluation device, and a robot system.

  Conventionally, a life evaluation device that evaluates the life of a bearing by using the temperature of the bearing, which is assumed to be the same as the estimated temperature of the reduction gear, in a relationship between a previously determined temperature of the bearing and a life temperature correction coefficient of the bearing. Is known (for example, refer to Patent Document 1).

Japanese Patent No. 4087435

However, in the life evaluation device described in Patent Literature 1, since the temperature of the bearing is regarded as being the same as the temperature of the speed reducer, there is a disadvantage that the error is large and the life cannot be correctly evaluated.
The present invention has been made in view of the above-described circumstances, and accurately measures the temperature of a component such as a bearing, and can accurately evaluate the life of the component, a temperature estimation device, a life evaluation device, and The purpose is to provide a robot system.

In order to achieve the above object, the present invention provides the following means.
One aspect of the present invention is a temperature estimating apparatus for estimating a temperature of a component included in the transmission mechanism in a machine including a motor and a transmission mechanism that transmits the power of the motor to a movable unit, A motor calorific value calculator for calculating a motor calorific value based on a current value; and a friction calorific value calculation for calculating a friction calorific value in the transmission mechanism based on a rotation speed of the motor and a friction coefficient of the transmission mechanism. And a lubricant for lubricating the component members is removed based on the frictional heating value calculated by the frictional heating value calculation unit and the motor heating value calculated by the motor heating value calculation unit. A temperature estimating apparatus comprising: a component temperature estimating unit configured to estimate a temperature of the component.

According to this aspect, the motor heating value is calculated by the motor heating value calculation unit based on the current value of the motor, and the friction in the transmission mechanism is calculated by the friction heating value calculation unit based on the friction coefficient of the transmission mechanism and the rotation speed of the motor. The calorific value is calculated. Then, the component temperature estimating unit estimates the temperature of the components excluding the lubricant based on the calculated motor heat value and friction heat value.
Compared with the conventional technology in which the temperature of the components is estimated as the same as the temperature of the speed reducer, the amount of heat generated by the motor, which greatly contributes to the temperature rise of the components, is taken into account. Can be accurately estimated.

In the above aspect, a cooling unit that cools the component may be provided according to the temperature of the component estimated by the component temperature estimating unit.
With this configuration, the component is cooled by the cooling unit that operates according to the temperature of the component. This makes it possible to keep the temperature of the component below a predetermined temperature.

In the above aspect, the motor heat generation amount calculation unit may calculate the motor heat generation amount based on a current value of the motor and a rotation speed of the motor.
In this way, when the heat generated by the rotation speed of the motor is large, the amount of heat generated by the motor can be calculated more accurately than in the case where the heat is calculated only from the current value of the motor.

Further, in the above aspect, the apparatus further comprises an air-cooling heat-dissipation calculating unit that calculates an air-cooling heat-dissipating amount based on the moving speed of the transmission mechanism, wherein the component member temperature estimating unit calculates the air-cooling heat-dissipating amount calculated by the air-cooling heat dissipation amount calculating unit. The temperature of the component may be estimated based on the amount of heat.
In this way, when the transmission mechanism is arranged on the movable part and moved, the forced air cooling is performed by the movement. The air-cooling heat radiation amount is calculated, and the component temperature estimating unit estimates the temperature of the component member based on the air-cooling heat radiation amount. Thereby, it is possible to estimate the temperature of the component members more suitable for the actual machine.

ここで、Ｔは前記構成部材の推定温度、Ｔ_０は室温、ｉは目標軸を含む目標軸構成部材温度に影響を与える軸、Ｄ_１，Ｄ_２，Ｄ_３，Ｄ_４，Ｄ_５，Ｄ_６は、予め実験により、種々のパターンの動作を実行し、各パターンにおける前記構成部材の温度、室温、発熱量、減速機の移動速度および他の発熱源の発熱量のデータを取得して同定した係数、Ｗ_３は空冷放熱量、Ｗ_４は他の発熱源の発熱量、Ｅ_ｉは前記モータ発熱量Ｗ_１ｉの係数、Ｆ_ｉは前記摩擦発熱量Ｗ_２ｉの係数であり、Ｅ_ｉおよびＦ_ｉのそれぞれは、予め実験により、種々のパターンの動作を実行し、各パターンにおける前記構成部材の温度、室温、発熱量、減速機の移動速度および他の発熱源の発熱量のデータを取得して同定した係数または予め設定した定数である。 In the above aspect, the component temperature estimating unit may estimate the temperature of the component using the following equation.

Here, T is the estimated temperature of the component, T ₀ is room temperature, i is an axis that affects the target axis component temperature including the target axis, D ₁ , D ₂ , D ₃ , D ₄ , D ₅ , D No. ₆ performs operations of various patterns in advance by experiments, and acquires and identifies data on the temperature, room temperature, heat generation amount, moving speed of the reduction gear and heat generation amount of other heat sources of the constituent members in each pattern. the coefficient, _{W 3} is air-cooled heat dissipation, _{W 4} is the amount of heat generated other heat sources, _{E i} is the coefficient of the motor heating value _{W 1i,} the _{F i} is the coefficient of the friction heating value _{W 2i, E i} and each F _i, by experiment, and perform the operations of various patterns, the temperature of the structural member in each pattern, at room temperature, heating value, obtains the data of the moving speed and other heat sources of the heating amount of the reducer Is a coefficient identified or a preset constant

Further, the constituent member may be a member whose life changes according to a temperature change.
In the above aspect, the constituent member may be a bearing for a rotating shaft included in the transmission mechanism.

Further, in the above aspect, the component member temperature estimating section estimates the temperature of the component member from the friction heat generation amount and the motor heat generation amount by machine learning using the friction heat generation amount and the motor heat generation amount. May be generated.
In this way, it is possible to accurately estimate the temperatures of the constituent members using the learned model based on the data of the frictional heating value and the motor heating value of various patterns.

Further, in the above aspect, a storage unit that stores a learned model generated by machine learning using the frictional heat generation amount and the motor heat generation amount is provided, and the component member temperature estimating unit includes the frictional heat generation amount and the The temperature of the component may be estimated using the learned model based on a motor heat value.
In this way, the temperature of the component is estimated using the learned model stored in the storage unit, so that the temperature of the component can be accurately estimated without generating a learned model from scratch. it can.

Further, in the above aspect, the machine learning is supervised learning using teacher data in which the friction heating value and the motor heating value are input data, and the measured values of the temperatures of the constituent members are associated with each other as labels. There may be.
In this way, the temperature of the component corresponding to the input data can be accurately estimated by using the measured value of the temperature of the component as the correct answer.

According to another aspect of the present invention, there is provided any one of the above temperature estimating devices, and a life estimating unit that estimates the life of the component based on the temperature of the component estimated by the component temperature estimating unit. Provided is a life evaluation device provided.
According to this aspect, the life of the component is estimated by the life estimator based on the temperature estimated by the component temperature estimator, so that the life can be accurately evaluated.

Further, the sun may include a remaining life calculating unit that calculates a remaining life based on the life estimated by the life estimating unit.
By doing so, the remaining life is calculated by the remaining life calculator, so that the replacement time can be confirmed in advance.

Further, in the above aspect, a replacement date calculation unit that calculates an estimated replacement date based on the life estimated by the life estimation unit may be provided.
By doing so, the replacement time can be more clearly recognized based on the estimated replacement date calculated by the replacement date calculation unit.

  According to another aspect of the present invention, one or more of the motors, one or more movable parts, and one or more of the transmission mechanisms connected by the constituent members and transmitting power of each of the motors to each of the movable parts are provided. And a control device for controlling the motor of the robot, and at least one of the above-mentioned life evaluation devices.

  ADVANTAGE OF THE INVENTION According to this invention, there exists an effect that the temperature of the component member except a lubricant can be evaluated accurately.

1 is an overall configuration diagram illustrating a robot system according to an embodiment of the present invention. FIG. 2 is a partial vertical sectional view illustrating an example of a joint portion of a robot provided in the robot system of FIG. 1. FIG. 2 is a block diagram of a part of the robot system 1. FIG. 4 is a block diagram illustrating a part of a modification of the robot system 1 of FIG. 3. It is a graph explaining the calculation method of the exchange date by the exchange date calculation part of a bearing in a modification. FIG. 6 is a diagram showing a display example of an estimated replacement date and a remaining life outputted by the temperature estimating device of FIG. 5.

A temperature estimation device (life evaluation device) 12 and a robot system 1 according to an embodiment of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, the robot system 1 according to the present embodiment includes a robot 2, a control device 3 for controlling the robot 2, and a display unit 4 connected to the control device 3.

The robot 2 has one or more links (movable parts) 5 and one or more joints. In the example shown in FIG. 1, a six-axis articulated robot can be used.
FIG. 2 shows an example of the joint 6 of the robot 2. The joint portion 6 includes a base 7, a link 5 supported swingably about an axis with respect to the base 7, and a reduction gear (transmission mechanism) 8 disposed between the link 5 and the base 7. And a motor 9 for generating power to be input to the speed reducer 8.

The inside of the reduction gear 8 is filled with grease (lubricating material) 10 to lubricate gears and bearings constituting the reduction gear 8. In FIG. 2, a bearing (bearing) 23, an O-ring (component) 31 serving as a seal member, and an external component are included as examples of components included in the reduction gear 8 and transmitting the power of the motor 9. And an oil seal 32 (a component member) for preventing the grease 10 from leaking. The bearing 23 supports a rotating shaft inside the speed reducer 8 not shown in FIG. Note that the constituent members in this specification include an O-ring 31 and an oil seal 32 related to these transmission members in addition to the transmission members that transmit the power of the motor 9. In this embodiment, temperature estimation and life estimation of the bearing 23 as one component will be described.
When the motor 9 is operated, the rotation of the motor 9 is reduced by the speed reducer 8 so that the link 5 is rotated with respect to the base 7.

The control device 3 includes a robot control unit (control device) 11 for controlling the robot 2 and a temperature estimating device 12 according to the present embodiment for estimating the temperature of the bearing 23 and estimating the life of the bearing 23.
FIG. 3 shows a partial block diagram of the robot system 1. As shown in FIG. 3, the temperature estimating device 12 calculates a room heat input unit 13 for inputting a room temperature, a motor heat generation amount calculation unit 14 for calculating a motor heat generation amount, and a friction heat generation amount in a bearing 23 in the speed reducer 8. A calculation unit for calculating the amount of frictional heat 15 to be calculated, a calculation unit for calculating the heat radiation amount of air cooling 16, a temperature estimating unit 17 for estimating the temperature of the bearing 23 based on the amount of heat calculated by the calculation units 14, 15, and 16. A life calculating unit (life estimating unit) 18 that calculates the life of the bearing 23 based on the estimated temperature, and a cooling unit that drives a fan (not shown) according to the temperature estimated by the component temperature estimating unit 17. 24.

The room temperature input unit 13 may be manually input by an operator or may be detected by a temperature sensor.
The motor heat generation amount calculation unit 14 calculates the equation (1) based on the motor state amount input from the robot control unit 11, that is, the current value of the motor 9 (motor current value) and the rotation speed of the motor 9 (motor rotation speed). Is used to calculate the heat value of the motor.

^{_{W 1 = A 1 × I M}} 2 + (A 2 × S M + A 3 × S M 2) (1)
here,
W ₁ is a motor calorific value,
A ₁ , A ₂ , A ₃ are coefficients,
I _M is the motor current value,
_SM is the motor rotation speed.
In the equation (1), the first term on the right side indicates a copper loss in the motor 9, and the second term indicates an iron loss.

Further, the frictional heat generation amount calculation unit 15 calculates the frictional heat generation amount by Expression (2) based on the motor state amount input from the robot control unit 11, that is, the friction torque and the motor rotation speed.
W ₂ = T × S _M
= (B ₁ + B ₂ × T _M + B ₃ × S _M ) × S _M (2)
here,
W ₂ is the calorific value of friction,
T is the friction torque,
B ₁ , B ₂ , B ₃ are the previously identified coefficients of friction,
T _M is the torque required to drive the link 5 of the robot 2 when there is no friction.
The torque T _M is generally calculated by a known calculation method such as a Lagrangian method or a Newton-Euler method using the position, acceleration, mass information, and the like of the link 5.

The air-cooling heat-dissipation calculating unit 16 calculates an air-cooling heat-dissipation amount that is generated because the relative speed is generated between the speed reducer 8 itself and the surrounding air when the speed reducer 8 itself driven by the robot 2 moves in the air. The moving speed of the robot 2 at the position of the speed reducer is calculated based on the rotation speed of the motor 9 input from the robot control unit 11, and the air-cooling heat radiation amount is calculated by the equation (3) based on the calculated moving speed. Is calculated.
W ₃ = C ₁ × S _R (3)
here,
W ₃ is air-cooling heat release amount,
C ₁ is a value calculated by the sum of the motor heating value W ₁ and the friction heating value W ₂ ,
S _R is the moving speed of the robot 2 at the position of the reduction gear 8.

ここで、
Ｔはベアリング２３の推定温度、
Ｔ_０は室温、
ｉは目標軸を含む目標軸ベアリング２３の温度に影響を与える軸、
Ｄ_１，Ｄ_２，Ｄ_３，Ｄ_４，Ｄ_５，Ｄ_６は、予め実験により、種々のパターンの動作を実行し、各パターンにおけるベアリング２３、室温、発熱量、減速機８の移動速度および他の発熱源の発熱量のデータを取得して同定した係数、
Ｗ_４は他の発熱源の発熱量、
Ｅ_ｉは予め実験により、種々のパターンの動作を実行し、各パターンにおけるベアリング２３の温度、室温、発熱量、減速機８の移動速度および他の発熱源の発熱量のデータを取得して同定したモータ発熱量Ｗ_１ｉの係数、
Ｆ_ｉは予め実験により、種々のパターンの動作を実行し、各パターンにおけるベアリング２３の温度、室温、発熱量、減速機８の移動速度および他の発熱源の発熱量のデータを取得して同定した摩擦発熱量Ｗ_２ｉの係数
である。 The component member temperature estimating section 17 estimates the temperature of the bearing 23 by the equation (4).

here,
T is the estimated temperature of the bearing 23,
T ₀ is room temperature,
i is an axis that affects the temperature of the target axis bearing 23 including the target axis;
D ₁ , D ₂ , D ₃ , D ₄ , D ₅ , and D ₆ perform various patterns of operations by experiments in advance, and determine the bearing 23, room temperature, calorific value, moving speed of the speed reducer 8, and the like in each pattern. Coefficients identified by acquiring the calorific value data of other heat sources,
W ₄ is the calorific value of other heat sources,
The E _i is preliminarily experiments, perform the operations of various patterns, the temperature of the bearing 23 in each pattern, at room temperature, heating value, and acquires the data of the moving speed and other heat sources of the heating amount of the reduction gear 8 Identification Coefficient of the _calculated motor heating value W _1i ,
The F _i is preliminarily experiments, perform the operations of various patterns, the temperature of the bearing 23 in each pattern, at room temperature, heating value, acquired by the data of the moving speed and other heat sources of the heating amount of the reduction gear 8 Identification Coefficient of the generated frictional heat value _W2i .

Other sources of heat may include other joints or devices in close proximity.
Further, heat radiation may be considered in addition to equation (4).
In the present embodiment, the estimated temperature T of the bearing 23 is calculated by the equation (4) when the robot 2 operates, and is equal to the room temperature when the robot 2 is stopped.

As an example, when each axis of the robot 2 which is a 6-axis articulated robot is set to J1-axis, J2-axis, J3-axis, J4-axis, J5-axis, and J6-axis, the motor 9 of J4-axis, J5-axis, and J6-axis is used. When the reduction gear 8 and the speed reducer 8 are densely affecting each other, the estimated temperature T of the bearing 23 having the J6 axis as the target axis is estimated by Expression (5).

Coefficients E ₄ are the J4 axis motor heating value _{W 14,}
Coefficient of E ₅ is the J5-axis motor heating value _{W 15,}
E ₆ The coefficient of J6 axis motor heating value _{W 16,}
Coefficient of friction heating value _{W 24} of F ₄ is the J4 axis,
Coefficient of friction heating value _{W 25} of F ₅ is J5 axis,
F ₆ is the coefficient of friction heating value _{W 26} of J6 axis.

In addition, in the equation (5), the case where the J1, J2, and J3 axes do not affect and the J4 and J5 axes affect the J6 axis has been illustrated, but the J1, A2, and J3 axes also have an effect. Is given, W ₁₁ , W ₁₂ , W ₁₃ , W ₂₁ , W ₂₂ , W ₂₃ , E ₁ , E ₂ , E ₃ , F ₁ , F ₂ , and F ₃ are added.
Also, in the equation (5), the case where the J4 axis and the J5 axis affect the J6 axis is illustrated, but the case where the J4 axis and the J5 axis do not affect the J6 axis similarly to the J1, J2, and J3 axes. , W ₁₄ , W ₁₅ , W ₂₄ , W ₂₅ (or E ₄ , E ₅ , F ₄ , F ₅ ) are 0.

The life calculation unit 18 can calculate the life of the bearing 23 using various methods. As an example of the life calculation, the life calculation unit 18 calculates the radical load and the axial load applied to the bearing 23 and the rotation speed of the motor 9 based on the rotation speed of the motor 9. In addition, the life calculating unit 18 uses the estimated temperature T of the bearing 23 estimated by the component temperature estimating unit 17 for the correspondence between the temperature of the bearing provided by the bearing manufacturer and the life temperature correction coefficient. Calculate the life temperature correction coefficient. The life calculation unit 18 can calculate the service life Sg of the bearing 23 using the calculated life temperature calculation coefficient, the number of rotations of the motor 9, the radical load and the axial load applied to the bearing 23, and the operating time of the motor 9. In another embodiment, a different calculation using the estimated temperature T of the bearing 23 may be used for calculating the life of the bearing 23.
Further, in the present embodiment, as shown in FIG. 3, the temperature estimating device 12 includes a remaining life calculating unit 19.

The remaining life calculation unit 19 calculates the remaining life using Expression (6).
Remaining life = (1−Sg / Sg0) × 100% (6)
Sg0 in the equation (6) is a preset rated life.

  The display unit 4 may display the remaining life itself calculated by the remaining life calculation unit 19, or may display a warning when the calculated remaining life becomes smaller than a preset threshold. Good.

    The fan driven by the cooling unit 24 is a device that blows air to the bearing 23. The cooling unit 24 drives the fan when the estimated temperature T of the bearing 23 estimated by the component temperature estimating unit 17 becomes equal to or higher than a preset threshold. On the other hand, when the estimated temperature T of the bearing 23 is lower than the threshold, the cooling unit 24 does not drive the fan. Thereby, when the temperature of the bearing 23 changes from less than the threshold to more than the threshold, the bearing 23 is cooled.

According to the temperature estimating device 12 and the robot system 1 including the same according to the present embodiment, the temperature of the bearing 23 inside the speed reducer 8 for transmitting the power of the motor is limited to the coefficient of friction of the speed reducer 8 only. Instead, the estimation is performed based on the heat value of the motor, so that the estimation is performed with high accuracy. Further, since the life of the bearing 23 is estimated based on the temperature of the bearing 23 estimated with high accuracy, there is an advantage that the life of the bearing 23 can be evaluated with high accuracy.
Further, since the heat value of the motor is calculated based on the motor current and the motor speed, when the heat generated by the motor speed is large, the heat value of the motor can be calculated with high accuracy. There is an advantage that can be evaluated with high accuracy. If the amount of heat generated by the rotation speed of the motor 9 is small, the iron loss in the second term on the right side of the equation (1) may be omitted.

In addition, according to the present embodiment, the temperature of the bearing 23 is estimated in consideration of the amount of air-cooled heat released by the reduction gear 8 that is disposed on the link 5 and moved. Thereby, the temperature of the bearing 23 can be more accurately estimated, and the life of the bearing 23 can be accurately evaluated.
Further, according to the present embodiment, since the remaining life is calculated and displayed instead of displaying the calculated life usage, there is an advantage that the operator can confirm the replacement time in advance.

In the present embodiment, the remaining life of the bearing 23 is calculated and displayed. However, as an alternative or in addition to this, the replacement date of the bearing 23 is calculated as shown in FIG. May be provided.
The replacement date calculation unit 20 uses the data of the life usage of the bearing 23 in the last several days and calculates the integrated value of the life usage using the least squares method as shown in FIG. Is calculated, and the time when the integrated value of the life usage reaches the rated life is predicted using the calculated increase rate. As an example, the following formula (7) shows a formula for calculating a recommended replacement date (estimated replacement date) using the integrated value of the life usage amount for the last 20 days.

ここで、
ｄは最も最新のＳｇを計算した日付
である。
すなわち、直近の数日のロボット２の使用状況がそのまま継続される場合に、寿命を使い切ることとなる日付が予測され、関節毎に表示部４に、図６に示されるように表示される。図６における第１ベアリングから第３ベアリングのそれぞれは、第１関節から第３関節に配置された各減速機に内蔵されたベアリングである。
このように交換日算出部２０により算出された推定交換日が表示部４に表示されることにより、交換時期をより明確に認識することができるという利点がある。式（７）においては最小二乗法を例示したが、これに限定されるものではなく、他の任意の近似計算法を採用してもよい。

here,
d is the date when the latest Sg was calculated.
That is, when the usage status of the robot 2 for the last several days is continued as it is, a date at which the life will be used up is predicted, and displayed on the display unit 4 for each joint as shown in FIG. Each of the first to third bearings in FIG. 6 is a bearing built in each reduction gear arranged in the first to third joints.
Since the estimated replacement date calculated by the replacement date calculation unit 20 is displayed on the display unit 4, there is an advantage that the replacement time can be more clearly recognized. In the equation (7), the least squares method is exemplified, but the present invention is not limited to this, and any other approximate calculation method may be adopted.

  The component member temperature estimating unit 17 determines the temperature of the bearing 23 by machine learning using the frictional heat value calculated by the frictional heat value calculation unit 15 and the motor heat value calculated by the motor heat value calculation unit 14. May be generated. Further, the generated learned model may be stored in the storage unit 25 illustrated in FIG.

The component member temperature estimating unit 17 performs supervised learning based on the frictional heat generation amount, the motor heat generation amount, the air cooling heat radiation amount calculated by the air cooling heat radiation amount calculating unit 16, and the actual temperature of the bearing 23. May be generated for use in estimating. The constituent member temperature estimating unit 17 performs, for example, a regression analysis using the multiple regression equation of the above equation (4) as a learning model, and calculates the coefficients D _{1 to} D ₆ , E _i , F used in the above equation (4). _A trained model is created by estimating all or part of _i .

  The learning by the component temperature estimating unit 17 is performed when the life evaluation device 12 functions as a learning mode. At this time, the component member temperature estimating unit 17 creates teacher data using the frictional heat generation amount, the motor heat generation amount, and the air-cooling heat release amount as input data, and the temperature as the measured value of the bearing 23 as a label (output data). Perform supervised learning using the created teacher data. As the temperature of the bearing 23 as a label, for example, the temperature of the bearing 23 measured by an operator via the component temperature input unit 26 shown in FIG. The temperature detected by a temperature sensor (not shown) attached inside or near the device may be automatically acquired. The component temperature estimating unit 17 stores the generated learned model in the storage unit 25, and uses the learned model when estimating the temperature of the bearing 23.

  In the present embodiment, the bearing 23 is illustrated as a component for transmitting the power of the motor 9, but may be applied to a component such as an oil seal 32, an O-ring 31, and a packing. The constituent members such as the bearing 23 described in the above embodiment can be said to be members whose lifespan changes according to a change in temperature. Further, the axis configuration of the robot 2 is not limited to the vertical articulated type shown in FIG. 1, and may be applied to the robot system 1 including the robot 2 having another arbitrary axis configuration.

  Although the temperature estimation device 12 of the present embodiment has the configuration shown in FIGS. 3 and 4, the configuration of the temperature estimation device 12 and the control by the configuration can be variously modified. For example, the temperature estimation device 12 may not include the cooling unit 24, and the temperature of the bearing 23 estimated by the component temperature estimation unit 17 may be used for control other than cooling. Further, the cooling unit 24 controls the on / off of the operation of the fan at the temperature as the threshold value, but may perform control to increase the rotation speed in proportion to the temperature, for example. The temperature estimation device 12 does not need to calculate the used life amount Sg and the remaining life of the bearing 23 without including the life calculation unit 18 and the remaining life calculation unit 19 in FIG.

1 Robot system 2 Robot 5 Link (movable part)
8 Reduction gear (transmission mechanism)
9 Motor 11 Robot control unit (control device)
12. Temperature estimation device (lifetime evaluation device)
14 Motor heat generation amount calculation unit 15 Friction heat generation amount calculation unit 16 Air cooling heat radiation amount calculation unit 17 Component temperature estimation unit 18 Life calculation unit (life estimation unit)
19 Remaining life calculator 20 Replacement date calculator 23 Bearing 23 (Bearing)
24 cooling unit 25 storage unit

Claims (14)

A motor, and a temperature estimating apparatus for estimating a temperature of a component included in the transmission mechanism in a machine including a transmission mechanism that transmits power of the motor to a movable unit,
A motor heating value calculation unit that calculates a motor heating value based on the current value of the motor,
A frictional heat generation amount calculation unit that calculates a frictional heat generation amount in the transmission mechanism based on a rotation speed of the motor and a friction coefficient of the transmission mechanism;
The constituent members excluding a lubricant for lubricating the constituent members based on the friction heat generation amount calculated by the friction heat generation amount calculation unit and the motor heat generation amount calculated by the motor heat generation amount calculation unit. A temperature estimating device comprising: a component temperature estimating unit for estimating the temperature of the component.   The temperature estimating device according to claim 1, further comprising a cooling unit that cools the component according to the temperature of the component estimated by the component temperature estimating unit.   The temperature estimating device according to claim 1, wherein the motor heating value calculation unit calculates the motor heating value based on a current value of the motor and a rotation speed of the motor.   An air-cooling heat radiation amount calculating unit that calculates an air-cooling heat radiation amount based on a moving speed of the transmission mechanism, wherein the component temperature estimating unit calculates the air-cooling heat radiation amount calculated by the air-cooling heat radiation amount calculating unit. The temperature estimating device according to any one of claims 1 to 3, wherein the temperature estimating device estimates the temperature. The temperature estimating device according to claim 1, wherein the component temperature estimating unit estimates the temperature of the component using the following equation.

Here, T is the estimated temperature of the component, T ₀ is room temperature, i is an axis that affects the target axis component temperature including the target axis, D ₁ , D ₂ , D ₃ , D ₄ , D ₅ , D No. ₆ performs operations of various patterns in advance by experiments, and acquires and identifies data on the temperature, room temperature, heat generation amount, moving speed of the reduction gear and heat generation amount of other heat sources of the constituent members in each pattern. the coefficient, _{W 3} is air-cooled heat dissipation, _{W 4} is the amount of heat generated other heat sources, _{E i} is the coefficient of the motor heating value _{W 1i,} the _{F i} is the coefficient of the friction heating value _{W 2i, E i} and each F _i, by experiment, and perform the operations of various patterns, the temperature of the structural member in each pattern, at room temperature, heating value, obtains the data of the moving speed and other heat sources of the heating amount of the reducer Is a coefficient identified or a preset constant   The temperature estimating device according to claim 1, wherein the constituent member is a member whose life changes according to a temperature change.   The temperature estimating device according to any one of claims 1 to 6, wherein the component is a bearing for a rotating shaft included in the transmission mechanism.   The component temperature estimating unit generates a learned model for estimating the temperature of the component from the friction heat value and the motor heat value by machine learning using the friction heat value and the motor heat value. The temperature estimating device according to claim 1. A storage unit that stores a learned model generated by machine learning using the friction heat generation amount and the motor heat generation amount,
The temperature according to any one of claims 1 to 7, wherein the component temperature estimating unit estimates the temperature of the component using the learned model based on the frictional heat value and the motor heat value. Estimation device.   The machine learning is supervised learning using teacher data in which the friction heating value and the motor heating value are input data and actual measured values of the temperatures of the constituent members are associated with each other as labels. 10. The temperature estimation device according to 9. A temperature estimating device according to any one of claims 1 to 10,
A life estimation unit for estimating the life of the component based on the temperature of the component estimated by the component temperature estimation unit.   The life evaluation device according to claim 11, further comprising a remaining life calculation unit that calculates a remaining life based on the life estimated by the life estimation unit.   The life evaluation device according to claim 11 or 12, further comprising a replacement date calculation unit that calculates an estimated replacement date based on the life estimated by the life estimation unit. One or more of the motors;
One or more moving parts,
A robot having one or more of the transmission mechanisms connected by the constituent members and transmitting the power of each of the motors to each of the movable parts;
A control device for controlling the motor of the robot;
A robot system comprising at least one of the life evaluation device according to any one of claims 11 to 13.

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