JP2008290126A - Control device for industrial machinery, and method for controlling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the vibration of industrial machinery while suppressing the enlargement of the device and the increase of cost. <P>SOLUTION: A control device 1 for controlling industrial machinery is equipped with: a servomotor; a crank rotatively driven by the servomotor; a slider provided so as to be reciprocated; and a driving mechanism having a connecting rod converting rotary movement from the crank into reciprocating movement, so as to be transferred to the slider. Further, the control device 1 is equipped with: a displacement sensor 21; a velocity sensor 22; and a damping control unit 25. The displacement sensor 21 and the velocity sensor 22 detect vibration information exhibiting the vibration of industrial machinery. The damping control unit 25 receives the vibration information, and forms a damping control signal for operating the driving mechanism so as to suppress the vibration of the industrial machinery. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a control device and control method for an industrial machine.

2. Description of the Related Art Conventionally, some industrial machines include a drive mechanism that reciprocates a slider by a drive force of a servo motor. In this drive mechanism, the rotation mechanism is driven to rotate by a servo motor, and the rotation motion of the rotation mechanism is converted into a reciprocating motion by the link mechanism and transmitted to the slider. For example, in the press machine disclosed in Patent Document 1, the driving force of the servo motor is transmitted to the slider via the feed screw mechanism and the link mechanism, so that the slider reciprocates up and down. As a result, the upper die provided on the slider approaches and separates from the lower die, and press working is performed.
JP 2003-290984 A

  In the industrial machine as described above, vibration may occur in the main body frame that supports the drive mechanism. If this vibration is transmitted to the ground or floor where the industrial machine is installed, the surrounding environment may be deteriorated. Further, in industrial machines, vibrations may cause a reduction in machining accuracy and productivity.

  On the other hand, as a means for suppressing transmission of vibration as described above to the ground, it is conceivable to support the main body frame by a vibration isolator that attenuates vibration by elasticity. However, in this case, even if it is possible to suppress the transmission of the vibration to the ground, there is a possibility that the vibration of the main body frame increases due to the decrease in the natural frequency due to the elastic support.

  It is also possible to suppress vibration of the main body frame by mounting a dynamic vibration absorber (dynamic damper) or an active vibration damping device (active mass damper) generally used for vibration suppression on the main body frame. However, there is a risk of increasing the size and cost of the apparatus.

  An object of the present invention is to suppress vibration while suppressing increase in size and cost of an industrial machine.

  A control device for an industrial machine according to a first aspect of the present invention includes a servomotor, a rotation mechanism that is rotationally driven by the servomotor, a slider that is reciprocally movable, a slider that converts the rotational motion from the rotation mechanism into a reciprocating motion A control device for controlling an industrial machine including a drive mechanism having a link mechanism for transmitting to a vibration mechanism, and includes a vibration information detection unit and a vibration suppression control unit. The vibration information detection unit detects vibration information indicating the vibration of the industrial machine. The vibration suppression control unit receives the vibration information and generates a vibration suppression control signal for operating the drive mechanism so as to suppress the vibration of the industrial machine.

  In this industrial machine control device, the servomotor is controlled by the vibration suppression control signal, so that the drive mechanism operates to suppress the vibration of the industrial machine. Thereby, the vibration of the industrial machine is suppressed. In addition, since the drive mechanism of the industrial machine is used for suppressing the vibration, the vibration can be suppressed without attaching a separate device to the industrial machine. For this reason, the enlargement of an industrial machine and the increase in cost can be suppressed.

  An industrial machine control device according to a second invention is the industrial machine control device according to the first invention, wherein the vibration suppression control unit uses vibration feedback information based on a feedback gain determined according to the angular position of the rotation mechanism. A vibration suppression control signal is generated.

  In this industrial machine control device, a feedback gain for generating a vibration suppression control signal from vibration information is determined according to the angular position of the rotation mechanism. For this reason, it is possible to control the operation of the drive mechanism in consideration of the nonlinearity of the drive mechanism. Thereby, the effect of vibration suppression can be improved.

  An industrial machine control device according to a third invention is the industrial machine control device of the first invention or the second invention, wherein the vibration suppression control unit is for suppressing vibration of the industrial machine as a vibration control signal. The torque in the rotation mechanism is calculated.

  In this industrial machine control device, the torque in the rotating mechanism for suppressing the vibration of the industrial machine is calculated as the vibration suppression control signal, and the operation of the drive mechanism is controlled by the torque control. Thereby, the vibration of the industrial machine can be suppressed.

  An industrial machine control device according to a fourth invention is the industrial machine control device according to any one of the first to third inventions, wherein the work control signal for operating the drive mechanism for work in the industrial machine is provided. A work control unit for generating, and a command signal generating unit for generating a command signal output to the servo motor by adding the work control signal and the vibration suppression control signal are further provided.

  In this industrial machine control device, a command signal output to the servo motor is generated by adding the work control signal and the vibration suppression control signal. Thereby, it is possible to achieve both control of the drive mechanism for work in the industrial machine and control of the drive mechanism for vibration suppression.

  According to a fifth aspect of the invention, there is provided a control method for an industrial machine comprising: a servo motor; a rotary mechanism that is rotationally driven by the servo motor; a slider that is reciprocally movable; A method for controlling an industrial machine comprising a drive mechanism having a link mechanism for transmitting to the vehicle, the step of detecting vibration information indicating the vibration of the industrial machine, and the drive mechanism so as to suppress the vibration of the industrial machine from the vibration information Generating a vibration suppression control signal for operating.

  In this industrial machine control method, the servomotor is controlled by the vibration suppression control signal, so that the drive mechanism operates to suppress the vibration of the industrial machine. Thereby, the vibration of the industrial machine is suppressed. In addition, since the drive mechanism of the industrial machine is used, vibration can be suppressed without attaching a separate device to the industrial machine. For this reason, the enlargement of an industrial machine and the increase in cost can be suppressed.

  In the industrial machine control device according to the present invention, the vibration of the industrial machine is suppressed by the drive mechanism operating so as to suppress the vibration of the industrial machine. In addition, since the drive mechanism of the industrial machine is used, vibration can be suppressed without attaching a separate device to the industrial machine. For this reason, the enlargement of an industrial machine and the increase in cost can be suppressed.

<Composition of industrial machinery>
An industrial machine 2 including a control device 1 (see FIG. 2) according to an embodiment of the present invention is shown in FIG. This industrial machine 2 is a press machine that performs press processing by reciprocating a mold up and down, and is a so-called servo press that can control the mold to an arbitrary speed and position by controlling a servo motor. It is. As shown in FIG. 2, the industrial machine 2 includes a main body 5 and a control device 1.

  The main body 5 includes the main body frame 3 and the drive mechanism 4 shown in FIG. 1 and is controlled by the control device 1.

  The main body frame 3 supports the drive mechanism 4 and is installed on the ground GR via a vibration isolator 6.

  The drive mechanism 4 includes a servo motor 7, a crank 8 as a rotation mechanism, a slider 9, and a connecting rod 10 as a link mechanism. The servo motor 7 can arbitrarily control the angular position and angular velocity by a command signal from the control device 1. The crank 8 is connected to the rotation shaft of the servo motor 7 and is driven to rotate by the servo motor 7. The connecting rod 10 is connected to the crank 8 and the slider 9, and converts the rotational motion from the crank 8 into a reciprocating motion and transmits it to the slider 9. The slider 9 is provided on the main body frame 3 so as to be linearly movable up and down, and can be reciprocated up and down by the operation of the connecting rod 10. Further, an upper die 11 is attached to the lower surface of the slider 9, and the upper die 11 approaches and separates from the lower die 12 as the slider 9 reciprocates up and down. Thereby, the workpiece | work W arrange | positioned between the upper mold | type 11 and the lower mold | type 12 can be processed into a desired shape. The lower mold 12 is attached to the upper surface of a bolster 13 provided below the slider 9.

  As shown in FIG. 2, the control device 1 includes a displacement sensor 21, a speed sensor 22, an angle sensor 23, an angular speed sensor 24, a vibration suppression control unit 25, a work control unit 26, and a command signal generation unit 27.

  The displacement sensor 21 detects the displacement of the main body frame 3.

  The speed sensor 22 detects the speed of the main body frame 3. The displacement of the main body frame 3 and the speed of the main body frame 3 are vibration information indicating the vibration of the industrial machine 2, and the displacement sensor 21 and the speed sensor 22 constitute a vibration information detection unit that detects vibration information.

  The angle sensor 23 detects the angular position of the servo motor 7, that is, the angular position of the crank 8.

  The angular velocity sensor 24 detects the angular velocity of the servo motor 7, that is, the angular velocity of the crank 8.

  The vibration suppression control unit 25 is a part that performs state feedback control for vibration suppression of the industrial machine 2, receives the displacement information of the main body frame 3 and the speed information of the main body frame 3, and from these information, the industrial machine 2 The vibration control signal for operating the drive mechanism 4 so as to suppress the vibration is generated. The vibration suppression control signal indicates a vibration suppression torque T ′ in the crank 8 for suppressing vibration of the industrial machine 2. Here, the damping feedback gain used to generate the damping control signal is determined according to the angular position of the crank 8, and the determination method will be described in detail later.

The work control unit 26 generates a work control signal for operating the drive mechanism 4 for work in the industrial machine 2, that is, press working. The work control unit 26 includes a motion setting unit 28 and an angular velocity feedback control unit 29. The motion setting unit 28 sets the motion of the slider 9 suitable for press working and outputs a setting signal for the angular velocity of the crank 8 for obtaining the motion. The angular velocity feedback control unit 29 performs the angular velocity feedback control of the crank 8 from the angular velocity setting signal of the crank 8 and the angular velocity information of the crank 8 detected by the angular velocity sensor 24, and generates a work control signal. The work control signal indicates a work torque T ₀ in the crank 8 for obtaining a desired motion of the slider 9. The work feedback gain in the work control unit 26 is also determined according to the angular position of the crank 8.

  The command signal generation unit 27 adds the work control signal generated by the work control unit 26 and the vibration suppression control signal generated by the vibration suppression control unit 25, thereby outputting a torque command signal output to the servo motor 7. Is generated.

<Control method of industrial machine 2>
Next, the control method of the industrial machine 2 by the control device 1 will be described based on the flowchart of FIG.

  First, in the first step S1 to the fourth step S4, various types of information on the industrial machine 2 are detected. Specifically, in the first step S1, the angular velocity of the crank 8 is detected, and in the second step S2, the angular position of the crank 8 is detected. In the third step S3, the speed of the main body frame 3 is detected, and in the fourth step S4, the displacement of the main body frame 3 is detected.

  In the fifth step S5, a work control signal is generated in the work control unit 26. As described above, the work control signal is a control signal for operating the drive mechanism 4 so as to obtain a desired motion of the slider 9 suitable for press working, and is calculated by feedback control based on the angular velocity of the crank 8. .

  In the sixth step S6, a vibration suppression control signal is generated in the vibration suppression control unit 25. As described above, the vibration suppression control signal is a control signal for operating the drive mechanism 4 so as to suppress vibration of the industrial machine 2 and is calculated by feedback control based on the displacement and speed of the main body frame 3.

  In the seventh step S7, the work control signal generated in the work control unit 26 and the vibration suppression control signal generated in the vibration suppression control unit 25 are added, and a torque command signal indicating a torque command value T of the crank 8 is obtained. Generated. The torque command signal is input to the servo motor 7 of the drive mechanism 4.

  Then, returning to the first step S1, the first step S1 to the seventh step S7 are repeated, whereby the feedback control of the servo motor 7 is performed.

<Determination method of feedback gain for vibration suppression>
Next, a method for determining the damping feedback gain used for generating the above-described damping control signal will be described.

  In the model diagram of the industrial machine 2 shown in FIG. 4, when the equation of motion of the industrial machine 2 is obtained, the following equation is obtained.

ここで、
ｍ_１：産業機械２のスライダ９を除く質量、
ｍ_２：スライダ９の質量
ｘ_１：本体フレーム３の変位
ｒ：クランク８の回転半径
θ：クランク８の角位置
ｋ：本体フレーム３と地面ＧＲとの間のバネ定数
ｌ：コンロッド１０の長さ
Ｊ：クランク８の慣性モーメント
ｃ：本体フレーム３と地面ＧＲとの間の減衰係数
Ｃｊ：クランク８の回転抵抗
Ｔ：クランク８に与えられるトルク
である。

here,
m ₁ : mass excluding the slider 9 of the industrial machine 2,
m ₂ : Mass of slider 9 x ₁ : Displacement of main body frame 3 r: Radius of rotation of crank 8 θ: Angular position of crank 8 k: Spring constant between main body frame 3 and ground GR l: Length of connecting rod 10 J: moment of inertia of the crank 8 c: damping coefficient between the main body frame 3 and the ground GR Cj: rotational resistance of the crank 8 T: torque applied to the crank 8

  Substituting θ = α + δ in the above [Equation 1], considering the angle variation δ near the constant angular position α, linearizing it for control system design and reverting it to the state equation, the following equation [Equation 2] It becomes.

以下、制御系の安定性を考慮して、最適レギュレータ理論により制振用フィードバックゲインを求める。

Hereinafter, considering the stability of the control system, the damping feedback gain is obtained by the optimal regulator theory.

  In general, in the optimal regulator theory, in the linear system expressed by the following [Equation 3],

ｑ：制御状態、ｕ：制御入力
以下の〔数４〕式で示される評価関数を最小にする制御入力ｕは、

q: control state, u: control input The control input u that minimizes the evaluation function represented by the following equation (4) is:

Ｑ，Ｒ：重み
以下の〔数５〕式によって示される。

Q, R: It is shown by the following [Formula 5] formula below the weight.

ここで、Ｐは以下の〔数６〕式で示されるリカッチ（Riccati）の方程式を満たす解である。

Here, P is a solution satisfying the Riccati equation expressed by the following [Equation 6].

従って、〔数６〕式を満たすＰを求め〔数５〕に代入することで、制御入力を得るためのフィードバックゲインＦと、制御入力を求めることができる。

Therefore, the feedback gain F for obtaining the control input and the control input can be obtained by obtaining P satisfying the equation [6] and substituting it into [Equation 5].

  Therefore, when the state equation expressed by the above [Expression 2] is applied to [Expression 3], the evaluation function is expressed by the following [Expression 7].

そして、この評価関数を最小にする制御入力すなわち制振用トルクＴ’は、以下の〔数８〕式で与えられる。

The control input that minimizes the evaluation function, that is, the damping torque T ′ is given by the following [Equation 8].

また、制振用トルクＴ’を求めるための制振用フィードバックゲインＦは以下の〔数９〕式で与えられる。

Further, a damping feedback gain F for obtaining the damping torque T ′ is given by the following [Equation 9].

ここで、Ｐは〔数６〕式を満たす解であり、上記の状態方程式〔数２〕式から、行列Ａ，Ｂは以下の〔数１０〕式となる。

Here, P is a solution satisfying [Expression 6]. From the state equation [Expression 2], the matrices A and B are expressed by the following [Expression 10].

なお、重みＱ，Ｒとしては実験値が用いられる。

Experimental values are used as the weights Q and R.

  In the above [Expression 4], [Expression 5], [Expression 6], and [Expression 9], the symbol “T” at the shoulder indicates transposition of the matrix.

The value of the damping feedback gain F obtained as described above varies depending on the value of the angular position α of the crank 8. An example in which the damping feedback gain F with respect to the angular position α of the crank 8 is plotted on a graph is shown in FIG. In FIG. 5, only the values of h ₁ and h ₂ are shown with h ₃ = 0.

<Features>
In the control device 1 of the industrial machine 2, the vibration of the industrial machine 2 can be suppressed using the operation of the drive mechanism 4 provided in the industrial machine 2. For this reason, the increase in size and cost of the industrial machine 2 can be suppressed.

  Further, since the angular position α of the crank 8 changes with time, the state equation represented by the above [Equation 2] has nonlinearity. Therefore, in the control device 1 of the industrial machine 2, the vibration of the industrial machine 2 can be more accurately suppressed by changing the damping feedback gain F according to the angular position α of the crank 8.

  Here, in FIG. 6, the simulation result of the vibration suppression control by the control apparatus 1 of the industrial machine 2 is shown. In FIG. 6, the horizontal axis indicates time, and the vertical axis indicates the displacement of the main body frame 3. The vibration in the industrial machine 2 is a combination of the vibration caused by the rotation of the crank 8 and the vibration generated during processing. In FIG. 6, the large vibration generated during processing is attenuated immediately after the vibration is generated. It can be seen that the time until the vibration is attenuated is shorter than when the vibration suppression control shown in FIG. 7 is not performed.

<Other embodiments>
(A)
In the above-described embodiment, a press machine is illustrated as the industrial machine 2. However, if the industrial machine includes the drive mechanism 4 that converts the rotary motion from the servo motor 7 into a reciprocating motion and transmits the reciprocating motion to the slider 9, the press machine is illustrated. The invention is applicable.

(B)
In the above embodiment, the drive mechanism 4 having the crank / slider mechanism is provided, but a drive mechanism having another link mechanism such as a Whitworth mechanism or a toggle link mechanism may be provided.

(C)
In the above embodiment, the damping feedback gain is calculated by the optimum regulator method, but other methods such as a pole placement method may be used.

(D)
In the above embodiment, the speed sensor 22 is provided to detect the speed of the main body frame 3. However, the speed may be calculated by differentiating the detected value from the displacement sensor 21.

  In the above embodiment, the angular velocity sensor 24 is provided to detect the angular velocity of the crank 8. However, the angular velocity may be calculated by differentiating the detected value from the angle sensor 23.

  INDUSTRIAL APPLICABILITY The present invention can suppress vibration while suppressing an increase in size and cost of an industrial machine, and is useful as a control device and control method for an industrial machine.

The figure which shows the structure of an industrial machine. The control block diagram which shows the structure of a control apparatus. Flow chart showing the control method of industrial machine The figure which modeled the industrial machine and showed the parameter of each part. The graph which shows the relationship between the feedback gain for damping | damping, and the angular position of a crank. The figure which shows the vibration of a main body frame in case the damping control of this invention is performed. The figure which shows the vibration of a main body frame in case the damping control of this invention is not performed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control apparatus 2 Industrial machine 7 Servo motor 8 Crank (rotation mechanism)
9 Slider 10 Connecting rod (link mechanism)
21 Displacement sensor (vibration information detector)
22 Speed sensor (vibration information detector)
25 Vibration control unit 26 Work control unit 27 Command signal generation unit

Claims (5)

A drive having a servo motor, a rotation mechanism that is rotationally driven by the servo motor, a slider that is reciprocally movable, and a link mechanism that converts the rotational motion from the rotational mechanism into a reciprocating motion and transmits the reciprocating motion to the slider. A control device for controlling an industrial machine including a mechanism,
A vibration information detection unit for detecting vibration information indicating vibration of the industrial machine;
A vibration control unit that receives the vibration information and generates a vibration control signal for operating the drive mechanism to suppress vibration of the industrial machine;
An industrial machine control device. The vibration suppression control unit generates the vibration suppression control signal from the vibration information using a feedback gain determined according to the angular position of the rotation mechanism.
The industrial machine control device according to claim 1. The vibration suppression control unit calculates a torque in the rotating mechanism for suppressing vibration of the industrial machine as the vibration suppression control signal.
The control device for an industrial machine according to claim 1 or 2. A work control unit that generates a work control signal for operating the drive mechanism for work in the industrial machine;
A command signal generation unit that generates a command signal output to the servo motor by adding the work control signal and the vibration suppression control signal;
The control device for an industrial machine according to claim 1, further comprising: A drive having a servo motor, a rotation mechanism that is rotationally driven by the servo motor, a slider that is reciprocally movable, and a link mechanism that converts the rotational motion from the rotational mechanism into a reciprocating motion and transmits the reciprocating motion to the slider. A method for controlling an industrial machine including a mechanism,
Detecting vibration information indicating vibration of the industrial machine;
Generating a vibration suppression control signal for operating the drive mechanism to suppress vibration of the industrial machine from the vibration information;
An industrial machine control method comprising:

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