JP6898779B2 - Molded product take-out machine - Google Patents

Description

The present invention relates to a molded product take-out machine capable of reducing the displacement vibration of the take-out head in a short time.

Japanese Patent Application Laid-Open No. 2010-110112 (Patent Document 1) describes a molded product take-out device provided with a take-out head (molded product take-out unit) driven by a drive source to take out a molded product from a molding machine. A table for inputting vibration components and a control means for controlling the moving speed of the take-out head so as to drive a servomotor (drive source) by feed-forward control using this table and suppress displacement vibration of the take-out head are provided. Therefore, the vibration of the take-out head is suppressed.

Further, in Japanese Patent Application Laid-Open No. 2004-223798 (Patent Document 2), a chuck and a chuck thereof are described in a molded product take-out machine for taking out a molded product from a resin molding machine by controlling the movement of a chuck holding the molded product between predetermined positions. Disclosed is a vibration suppression device for a molded product take-out machine, which is provided with a dynamic vibration absorbing device for generating vibration that cancels the residual vibration of the movable body when the movement is stopped at least one of the movable bodies for moving the article. The dynamic vibration absorber used is to enclose the fluid in a container so that it can flow and vibrate it, and to converge the vibration by the damping rate due to the viscosity of the fluid.

Japanese Unexamined Patent Publication No. 2010-11102 Japanese Unexamined Patent Publication No. 2004-223798

The positioning control function by the servo motor has been completed in the molded product take-out machine, etc., in which the take-out head (attachment) is attached to the tip of the elevating frame attached to the moving base provided in the pull-out frame driven by the servo motor. There is a problem that displacement vibration occurs in the attachment even afterwards. Therefore, in the conventional technique described in Patent Document 1, there is a problem that it takes time to suppress the displacement vibration.

Further, in the conventional technique described in Patent Document 2, it is necessary to individually prepare a dynamic vibration absorbing device utilizing the viscosity of a fluid that generates appropriate resonance vibration in response to a change in extraction conditions, which is a problem in terms of versatility. was there. Therefore, it is conceivable to use an electric actuator as a dynamic vibration absorber, but if all of the displacement vibration is absorbed by the electric actuator, a large electric actuator with a heavy weight is required, and such a large electric actuator is taken out. It was not realistic to attach it to a head or the like.

An object of the present invention is to provide a molded product take-out machine capable of suppressing displacement vibration of an attachment in a shorter time than before by using active control.

Another object of the present invention is to suppress the displacement vibration of the attachment in a shorter time than before by performing active control in cooperation with various vibration damping functions of the positioning servo device of the servomotor. The purpose is to provide a molded product take-out machine.

The molded product take-out machine to be improved by the present invention is a molded product take-out machine having an attachment to an approach frame controlled by a positioning servo device using a servomotor. The servo motor may be an AC servo motor or a DC servo motor as long as it can be servo-controlled. Further, the attachment is used for taking out a molded product such as a take-out head and a cutter. In the present invention, the displacement vibration detection unit that detects the displacement vibration of the attachment and the active control that suppresses the displacement vibration of the attachment by adding the vibration of the opposite phase to the displacement vibration detected by the displacement vibration detection unit from the electric actuator to the attachment. It is equipped with a control device. Then, the active control device performs active control together with at least the positioning control of the positioning servo device. According to the present invention, since at least the positioning control and the active control of the positioning servo device are used in combination, the displacement vibration of the attachment can be suppressed in a shorter time than before. Further, when the positioning control function of the servo device and the active control are used together, a small and lightweight electric actuator can be used as compared with the case where the active control alone controls the vibration.

When a belt transmission mechanism or a rope transmission mechanism driven by a servomotor is used, it is often not possible to suppress the displacement vibration of the attachment in a short time even if only the positioning control by the servomotor is performed. .. Therefore, it is considered to use an active control device, but it is difficult to control the timing of starting the active control in the active control using a dynamic vibration absorbing device that utilizes the viscosity of the liquid as shown in Patent Document 2. In addition, if the weight or center of gravity of the molded product is changed, it becomes impossible to perform accurate vibration damping control. Therefore, in the present invention, when the molded product is taken out, active control is performed in which the displacement vibration detected by the displacement vibration detection unit and the vibration having the opposite phase to the displacement vibration are added to the attachment from the electric actuator to suppress the displacement vibration of the attachment.

Further, when the vibration damping control and the active control of the positioning control function by the servomotor are used together, it is not necessary to control the magnitude of the output of the electric actuator especially when the output of the electric actuator is small. However, when the output of the electric actuator becomes large, if the weight and installation position of the electric actuator are not taken into consideration, the active control impedes the positioning control function by the servomotor or temporarily increases the displacement vibration. It may not be possible to shorten the vibration time. When such a situation is assumed, the active controller is more than the maximum output of the electric actuator after the amplitude of the displacement vibration of the attachment is attenuated to a predetermined magnitude or until it can be regarded as attenuated. It is preferable to perform limited active control at a low output. In this way, since the active control is started together with the positioning control function by the servomotor, it is possible to smoothly shift from the vibration damping control by the positioning control by the servomotor to the vibration damping by the active control. As a result, the displacement vibration of the attachment can be smoothly suppressed in a shorter time than before by using a lightweight and compact electric actuator. It is preferable that the low output is set so as not to affect the positioning control by the servomotor. In this case, it is preferable that the active controller gradually or gradually increases the output of the electric actuator from a low output. In this way, it is possible to prevent the rise of the active control from adversely affecting the vibration damping control.

After the amplitude of the displacement vibration of the attachment is attenuated to a predetermined magnitude or until it can be regarded as attenuated, active control limited to an output lower than the maximum output of the electric actuator is performed, depending on the capacity of the electric actuator. Since vibration damping by the electric actuator is positively performed from that point, a lightweight and compact electric actuator can be used. Therefore, it is practically possible to apply active control using an electric actuator to a molded product take-out machine. Further, if the electric actuator is lightweight and small, the electric actuator can be attached to the attachment itself or another part.

The present invention can be applied not only to suppress the displacement vibration in the uniaxial direction but also to suppress the displacement vibration in the plurality of axial directions. When suppressing the displacement vibration in the plurality of axial directions, an electric actuator may be provided for each axial direction, and the displacement vibration in each axial direction may be suppressed by active control.

The active control is not only when the positioning servo device performs only positioning control, but also when the positioning servo device performs vibration damping control together with the positioning control, the positioning servo device performs jerk control together with the positioning control. It can also be applied when the positioning servo device is performing vibration damping control and jerk control together with positioning control.

Specifically, the active control device can determine that the amplitude of the displacement vibration has been attenuated to a predetermined magnitude by comparing the output of the displacement vibration detection unit with the threshold value. The threshold value for determining the predetermined size will be determined in the preliminary test.

When the active control is performed in combination with the vibration damping control or the jerk control in the servo device of the servo motor, the active control device determines that the amplitude of the displacement vibration has been attenuated to a predetermined magnitude. It may be determined when a predetermined timer time has elapsed from a predetermined operation time in the positioning control by the servomotor. The timer time setting in this case can also be determined by a preliminary test. Further, the timer time can be set appropriately by the manager of the molded product take-out machine at the site.

It is preferable that the predetermined operation time is either the start time of the positioning control by the servomotor, when the completion command is output, or before or after the completion command is output. For the actual setting of the timer time, it is preferable to include a timer time adjustment unit for adjusting the timer time.

When the amplitude of the displacement vibration is considered to have been attenuated to a predetermined magnitude, the active control device indicates that the ejector retract limit signal, the ejector advance limit signal, the mold opening / closing signal, and the mold opening limit from the molding machine are reached. It may be operated when a signal or a mold closing signal is output. The time when the ejector backward limit signal, ejector forward limit signal, mold opening / closing signal, mold opening signal or mold closing signal from the molding machine is generated is completed after the start time of the positioning control by the servomotor. It is issued before the command is output. Therefore, as the operation start timing of the active control device, an ejector backward limit signal, an ejector forward limit signal, a mold opening / closing signal, a mold opening signal, or a mold closing signal from the molding machine can be used. In this way, the ejector backward limit signal, ejector forward limit signal, mold opening / closing signal, mold opening signal, or mold closing signal transmitted from the molding machine side to the molded product ejecting machine side are used as the operation start timing. Then, since it is not necessary to prepare special signal processing, a timer, or the like for timing determination, the configuration of the active control device becomes simple.

When the take-out head needs to position the take-out head after taking out the molded product from the mold of the molding machine, the active control device can consider that the amplitude of the displacement vibration has been attenuated to a predetermined magnitude. Can be determined based on the signal output from the peripheral device of the molded product take-out machine. In this way, the active control can be effectively utilized even in the direction changing operation, the opening operation, and the like other than the taking-out operation.

When using a displacement vibration detection unit that outputs a motor current signal of a servomotor, a torque signal of a motor, or a signal proportional to a motor current signal or a torque signal of a motor as a displacement vibration detection signal for detecting displacement vibration, It may be determined based on the displacement vibration detection signal that the amplitude of the displacement vibration has been attenuated to a predetermined magnitude. By using the displacement vibration detection signal in this way, it is possible to determine the start timing of active control without installing a special sensor.

The active control device is the number of digital signals obtained when the displacement vibration detected by the displacement vibration detection unit is A / D converted when the amplitude of the displacement vibration is considered to have been attenuated to a predetermined magnitude. Alternatively, it may be determined based on a change in the signal width of the digital signal. The effective number of digital signals or the ratio of the signal width of the digital signals may be appropriately determined by a preliminary experiment.

It is a figure which shows the whole structure of the molded article take-out machine of embodiment of this invention. It is a partial schematic perspective view for demonstrating an example of the mounted state of an electric actuator. It is a block diagram which shows an example of the structure of an active vibration apparatus. (A) and (B) are a perspective view and a cross-sectional view of an example of an electric actuator that can be used in this embodiment. It is a figure used for demonstrating the basic structure and operation of the phase correction part, the additional vibration detection part and the drive signal generation part of FIG. (A) is a waveform diagram showing the vibration state of the take-out mechanism during the pull-out operation so that the vibration waveform measured by the laser displacement meter and the torque command waveform of the servo motor can be compared, and (B) is the vibration waveform and the servo. It is a figure which shows the comparison result with the torque command waveform of a motor. From the position where the drawing operation of the molded product starts, when the vibration damping control of the servomotor positioning servo device is used and when the vibration damping control is not used, in addition to the positioning control by the servomotor without active control. It is a figure which shows a plurality of types of waveforms, and a partially enlarged waveform until the vibration suppression operation is completed. Shows multiple types of waveforms and partially enlarged waveforms that show the control results when active control and servomotor positioning control and vibration damping control are used together, and when active control is performed but servomotor vibration damping control is not used together. It is a figure. Timer time period that determines when only the positioning control of the servomotor is performed without active control, when the positioning control is performed by the servomotor, and when the amplitude of the displacement vibration is in a state where it can be regarded as attenuated to a predetermined magnitude. It is a plurality of types of waveform diagrams and a partially enlarged waveform diagram showing the control results when active control is used in combination with. It is a conceptual waveform diagram for showing the displacement vibration of the take-out head when the positioning control function of a servo device, the vibration damping function and / or the jerk control are used together, and the vibration suppression effect when the active control is used together. To explain the operation when the gain of the drive signal generator is set to 10% and the gain is set to 100% after 0.4 seconds until t = 0.4 seconds immediately after the first amplitude of the servomotor feedback speed is generated. It is a waveform diagram. It is a waveform diagram which shows the result of having tested three kinds of patterns which changed the output condition of active control in the case of performing vibration damping by active control without performing the positioning control function by a servomotor. It is a figure for demonstrating the operation state when the taking-out mechanism performs a stop operation at a molded article open position.

Hereinafter, an example of an embodiment of the molded article take-out machine of the present invention will be described in detail with reference to the drawings.

<Structure of molded product take-out machine>
FIG. 1 is a diagram showing an overall configuration of a molded product take-out machine 1 according to the present embodiment. FIG. 2 is a partial schematic perspective view for explaining an example of the mounted state of the electric actuator. The molded product take-out machine 1 is a traverse-type molded product take-out machine, and the base is supported by a fixed platen of a molding machine (not shown). The molded product take-out machine 1 shown in FIG. 1 includes a traverse frame 3, a control box 5, a first traveling body 6, a drawing frame 7, a runner elevating unit 8, and a molded product adsorbing elevating unit 9. I have. The traversing frame 3 has a cantilever beam structure extending in the X direction horizontally orthogonal to the longitudinal direction of the molding machine (not shown). The first traveling body 6 is supported by the traversing frame 3, and moves back and forth in the X direction along the traversing frame 3 with the AC servomotor 11 included in the servo mechanism as a drive source. The drawing frame 7 is provided on the first traveling body 6 and extends in the Y direction parallel to the longitudinal direction of the molding machine. A molded product suction elevating unit 9 is supported on the drawing frame 7 so as to be movable in the Y direction by using a servomotor 13 (AC servomotor in the present embodiment) included in the servo mechanism as a drive source. In the present embodiment, the belt 15 is rotationally driven by the servomotor 13, and the second traveling body 17 as a base included in the molded product suction elevating unit 9 and supported by the drawing frame 7 moves in the Y direction. To do. In the present embodiment, the second traveling body 17 is moved by the belt transmission mechanism using the belt 15, but a rope transmission mechanism using a rope as a force transmission means may be used instead of the belt transmission mechanism. ..

The elevating unit 9 for adsorbing the molded product includes an elevating frame 19 as an approach frame that elevates and elevates in the vertical direction (Z direction) by the drive source 18, an reversing unit 21 that rotates around the frame line of the elevating frame 19, and an inversion unit. It is provided with a take-out head 23 as an attachment provided on the 21. In the present embodiment, the take-out mechanism 24 is composed of the reversing unit 21 and the take-out head 23. When the reversing unit 21 is not provided, the take-out mechanism 24 is configured only by the take-out head 23. Further, in the present embodiment, an electric actuator 25 including an exciting coil and a mover having a permanent magnet driven by the exciting coil is attached to the extraction head 23 of the extraction mechanism 24. A first acceleration sensor 27 is attached to the mover of the electric actuator 25. Theoretically, the mounting position of the electric actuator 25 is not limited to the take-out head 23, and it goes without saying that the electric actuator 25 may be mounted on the reversing unit 21, the elevating frame 19, and the second traveling body 17. is there.

<Configuration of active control device>
The molded product take-out machine 1 of the present embodiment includes an active control device 31 shown in FIG. 3 in a control unit not shown in FIG. The active control device 31 includes a displacement vibration detection unit 33, a phase correction unit 34, an electric actuator 25 mounted on the take-out head 23 to suppress horizontal or vertical vibration of the take-out head 23, and additional vibration. It includes a detection unit 35 and a drive signal generation unit 37.

The electric actuator 25 may have any structure as long as it can apply vibration of any power and any frequency to the take-out head 23 within the range of capability. In this embodiment, an electromagnetic actuator manufactured by Sinfonia Technology Co., Ltd. under the product number of RM040-021 is used. In the present embodiment, since the take-out mechanism 24 is composed of the reversing unit 21 mounted on the elevating frame 19 and the take-out head mounted on the reversing unit 21, the electric actuator 25 is attached to the take-out head 23 as described above. I am wearing it. This is because the reversing unit 21 has a predetermined rigidity, so that vibration can be effectively suppressed. In order to suppress the vibration in the horizontal direction, the electric actuator 25 is attached so that the vibration direction generated by the electric actuator is in the horizontal direction. Then, in order to suppress the vibration in the vertical direction, the actuator may be attached so that the vibration direction generated by the electric actuator is in the vertical direction. The present invention can of course be applied to the case where a plurality of electric actuators are used to suppress vibration in a plurality of axial directions.

4 (A) and 4 (B) show a perspective view and a cross-sectional view of an example of the electric actuator 25'that can be used in the present embodiment. In this electric actuator 25'B, the mover 25'B is arranged at the center of the tubular stator 25'A, and the mover 25'B is supported by the stator 25'A by three leaf springs 25'C. Has a structure that has been modified. The operating range of the mover 23'C is regulated by the stopper 45'D. The electric actuator 25'operates on the same principle as a so-called cylindrical linear motor. Active control is performed by fixing the stator 25'A to the take-out head and transmitting the vibration of the mover 25'B to the stator 25'A. The above-mentioned acceleration sensor 27 is attached to the mover 25'B.

The displacement vibration detection unit 33 includes a displacement vibration detection signal S1 that includes information on a displacement vibration frequency component proportional to the displacement vibration in the horizontal direction of the take-out head 23 based on the output of the second acceleration sensor 38 mounted on the take-out head 23. Is output. The displacement vibration includes a plurality of vibration frequency components based on the primary vibration, the secondary vibration, and the like generated by the operation of the elevating frame 19 and the take-out head 23. The vibration frequency component included in the displacement vibration changes depending on the structure of the belt-type or rope-type transport mechanism provided between the servomotor 13 and the elevating frame. The take-out mechanism 24 of the molded product take-out machine needs to enter between the two molds of the molding machine. For this reason, in order to attach the electric actuator 25 to the take-out mechanism 24 and suppress the vibration of the take-out head 23 by the electric actuator 25, it is desirable to use a lightweight and small electric actuator.

As the displacement vibration detection unit 33, it goes without saying that a vibration detection device other than the acceleration sensor or a vibration detection device such as a laser displacement meter can be used.

<Details of active control device>
In the present embodiment, even when a lightweight and small electric actuator is used, positioning control, vibration damping control, jerk control, and active control by a servomotor are performed so that the vibration damping ability can be fully utilized. Combined. In this embodiment, the positioning control function by the servomotor and the active control are used together. FIG. 5 is a diagram used for explaining the basic configuration and operation of the phase correction unit 34, the additional vibration detection unit 35, and the drive signal generation unit 37 of FIG. In FIG. 5, in order to facilitate understanding, the positioning control function by the servomotor is not executed, but only the active control is performed. The combined use of positioning control and active control by the servomotor will be described later.

The phase correction unit 34 corrects the phase shift of the displacement vibration detection signal S1 output by the displacement vibration detection unit 33 that receives the output of the second acceleration sensor 38 based on the phase shift information obtained in advance, and corrects the displacement vibration. The detection signal S1'is generated. A phase shift occurs between the displacement vibration detection signal S1 and the actual displacement vibration due to various factors such as the configuration of the displacement vibration detection unit 33. In the case of a molded product take-out machine, once the setting is made, the shape and weight of the take-out mechanism 24 and the molded product to be taken out do not change. Therefore, this phase shift can be obtained in advance by pre-measurement before starting the take-out operation. Therefore, in the present embodiment, the phase shift of the displacement vibration detection signal S1 is corrected by the phase shift information obtained in advance to generate the corrected displacement vibration detection signal S1', and the occurrence of oscillation based on the phase shift is prevented.

The additional vibration detection unit 35, which receives the output of the first acceleration sensor 27 as an input, detects the additional vibration in the horizontal direction generated by the electric actuator 25 itself, and detects the additional vibration including the information of the additional vibration frequency component of the additional vibration. The signal S2'is output. When the electric actuator 25 is operated using only the corrected displacement vibration detection signal S1'to perform the vibration suppression operation, the horizontal additional vibration frequency component of the electric actuator 25 itself is included in the displacement vibration frequency component. .. However, if this additional vibration frequency component is not taken into consideration, vibration damping using the electric actuator 25 cannot be realized quickly and without oscillating. Therefore, in the present embodiment, the accelerometer 27 mounted on the mover of the electric actuator 25 and detecting the acceleration of the mover is used as the additional vibration detection unit 35. Currently, as the first and second acceleration sensors 27 and 38, for example, semiconductor type acceleration sensors can be used. Semiconductor accelerometers with dimensions that can be attached to movers are on the market. In this embodiment, an accelerometer sold by Kionix, Inc. under the product name of KXR94-2050 is used.

The drive signal generation unit 37 vibrates in the horizontal direction of the take-out head 23 of the take-out mechanism 24 based on the displacement vibration frequency component included in the corrected displacement vibration detection signal S1'and the additional vibration frequency component included in the additional vibration detection signal. The drive signal necessary for actively controlling the electric actuator 25 is generated so as to suppress the above. The vibration may not be suppressed only by the drive signal for driving the actuator generated based only on the displacement vibration detection signal S1 including the information of the displacement vibration frequency component. The reason is that the displacement vibration frequency component includes the additional vibration (additional vibration frequency component) generated due to the vibration of the actuator itself. Therefore, the vibrator of the electric actuator 25 that generates vibration for suppressing the horizontal vibration of the take-out head 23 from the corrected displacement vibration detection signal S1 ′ in which the detection signal S1 including the information of the displacement vibration frequency component is phase-corrected. The drive signal Sa generated by excluding the additional vibration detection signal S2'proportional to the speed obtained by integrating the acceleration signal S2 of the acceleration sensor 27 including the information of the additional vibration frequency component due to the additional vibration is used. As a result, the damping of the additional vibration can be increased to prevent the oscillation, and the active control using the electric actuator 25 becomes more effective. As a result, the vibration of the take-out head 23 can be reliably suppressed in a shorter time than before.

FIG. 5 is a waveform diagram showing the process of generating a drive signal Sa when only active control is performed and vibration control is performed by the electric actuator 25 without performing vibration control control by positioning control by the servomotor. is there. As shown in FIG. 5, the drive signal generation unit 37 includes a first gain adjustment unit 37A, a second gain adjustment unit 37B, and a calculation unit 37C. The first gain adjusting unit 37A adjusts the gain of the corrected displacement vibration detection signal S1'output from the phase correction unit 34. The second gain adjusting unit 37B adjusts the gain of the additional vibration detection signal S2'output from the additional vibration detection unit 35. The first gain adjusting unit 37A and the second gain adjusting unit 37B adjust the difference in dimension and amplitude between the corrected displacement vibration detection signal S1'and the additional vibration detection signal S2' to enable calculation. Then, the calculation unit 37C performs a calculation to reduce or eliminate the influence of the additional vibration frequency component generated by the additional vibration of the actuator included in the displacement vibration frequency component, and adjusts the gain from the gain-adjusted corrected displacement vibration detection signal S1'. The operation for removing the additional vibration detection signal S2'is executed. If the polarity of the output of the acceleration sensor 27 is negative, the calculation unit 37C will perform an addition calculation. The calculation unit 37C has a timing determination function for determining the timing for starting to make maximum use of the active control when the positioning control function by the servomotor and the active control are used in combination. In the example of FIG. 5, this function is not used.

It is preferable that the active control device 31 is always in the operating state when the molded product ejecting machine is in the operating state. In this way, the vibration of the take-out head 23 is always suppressed, so that the molded product can be taken out without being deformed, and the molded product that has not been completely cured after being taken out by the take-out head 23 is prevented from being deformed. it can. Further, if the active control device 31 is in an operating state at least when the take-out head 23 is stopped in the mold of the molding machine, the take-out head 23 can quickly and surely take out the molded product.

Further, the active control device 31 may be in an operating state when the take-out head 23 stops at the molded product open position or when the take-out head 23 stops when the moving direction is changed. By doing so, it is possible to prevent deformation of the molded product that has not yet been completely cured.

<Combined use of servo motor positioning control and active control>
In the present embodiment, the positioning control of the servomotor and the active control are used together. When the servomotor positioning control and the active control are used in combination, the active control may be performed at the same time as or before the start of the servomotor positioning control if the output of the electric actuator is not so large. However, when the output of the electric actuator becomes large, it may become a problem to use the positioning control of the servomotor and the active control at the same time from the initial stage of vibration damping. Therefore, in the present embodiment, the active control device 31 is active after the amplitude of the displacement vibration of the take-out head 23 is attenuated to a predetermined magnitude by the positioning control by the servomotor 13 or when it can be regarded as attenuated. Actively control. The positioning control of the servomotor is a control function generally mounted on a commercially available servo amplifier 39, and is a control for positioning while suppressing vibration of the drive frame of the servomotor when a stop command is output. The commercially available servo amplifier 39 is generally equipped with a vibration damping control function for suppressing vibrations of a specific frequency and a jerk control function for suppressing the acceleration change rate within a predetermined range. The servo amplifier 39 is configured to output a completion command when the positioning is completed.

However, when the belt transmission mechanism driven by the servomotor 13 is used, the displacement vibration of the take-out head 23 may not be suppressed in a short time only by the positioning control by the servomotor. Therefore, the active control by the active control device 31 is used together with the positioning control by the servomotor. In the present embodiment, when the molded product is taken out, the displacement vibration detected by the displacement vibration detection unit 33 and the vibration having the opposite phase to the displacement vibration are added from the electric actuator 25 to the take-out head 23 to suppress the displacement vibration of the take-out head 23. In the present embodiment, the active control device 31 positively starts after the amplitude of the displacement vibration of the take-out head 23 is attenuated to a predetermined magnitude by the positioning control function by the servomotor or when it can be regarded as attenuated. Active control is performed. When the amplitude of the displacement vibration of the take-out head 23 is attenuated to a predetermined magnitude by the positioning control function by the servomotor or when it can be regarded as attenuated, if active control is positively performed, the servomotor initially performs the active control. Vibration control is performed by positioning control, and later vibration control is performed by active control by the electric actuator 25. As a result, a lightweight and compact electric actuator can be used. Needless to say, the active control can be performed not only at the time of taking out the molded product but also at any time when the positioning control is performed by the servomotor.

Specifically, when the positioning control by the servomotor and the active control are used together, the active control device 31 attenuates the amplitude of the displacement vibration of the take-out head 23 to a predetermined magnitude by the positioning control function by the servomotor. Active control is actively started when the state can be regarded as having been done. After the amplitude of the displacement vibration of the take-out head 23 is attenuated to a predetermined magnitude by the positioning control function by the servomotor or before it can be regarded as attenuated, the active is limited by the output lower than the maximum output of the electric actuator. Take control.

The fact that the amplitude of the displacement vibration is attenuated to a predetermined magnitude (active control start timing) is determined based on the output of the displacement vibration detection unit 33. Specifically, a comparison means for generating a start timing signal by comparing the output of the first gain adjusting unit 37A of FIG. 5 with the threshold values corresponding to the plus and minus "predetermined magnitudes" in the calculation unit 37C is provided. Provide. This comparison means generates a start timing signal when it determines that the output of the first gain adjusting unit 37A is within the threshold value corresponding to the plus and minus "predetermined magnitudes". Then, the calculation unit 37C outputs the actuator drive signal Sa when the start timing signal is generated. This threshold value will be determined by a preliminary test.

Further, the active control device 31 is provided with a timer means for counting the timer time in the calculation unit 37C, and when the amplitude of the displacement vibration is considered to have been attenuated to a predetermined magnitude, a predetermined value in the positioning control by the servomotor is obtained. It may be determined when a predetermined timer time has elapsed from the operation time. The predetermined operation time can be any time of the start time of the positioning control by the servomotor, when the stop command is output, or before and after the stop command is output. The timer time setting in this case is also determined by a preliminary test. For the actual timer time setting, it is preferable to include a timer time adjustment unit for adjusting the timer time. If the timer time adjustment unit is provided, the administrator of the molded product take-out machine can appropriately set the timer time on site.

Further, as the displacement vibration detection unit, a servomotor motor current signal or motor torque signal or a signal proportional to the motor current signal or motor torque signal may be used as a displacement vibration detection signal for detecting displacement vibration. Good.

Further, the active control device 31 cuts the output of the displacement vibration detection unit 33 (the output of the phase correction unit 34 in the present embodiment) when the amplitude of the displacement vibration is equal to or larger than a predetermined magnitude in the calculation unit 37C. A filter circuit may be provided. When the output is output from the filter circuit, the calculation unit 37C executes the calculation assuming that the amplitude of the displacement vibration has been attenuated to a predetermined magnitude. The cut frequency of the filter circuit will be determined by the test. In this case as well, there is an advantage that it is not necessary to install a special sensor. If a cut frequency adjusting unit for adjusting the cut frequency is further provided, versatility can be enhanced.

Further, the active control device is a digital signal obtained when the displacement vibration detected by the displacement vibration detection unit is A / D converted when the amplitude of the displacement vibration is considered to have been attenuated to a predetermined magnitude. It may be determined based on the change in the number or the signal width of the digital signal. The effective number of digital signals or the ratio of the signal width of the digital signals may be appropriately determined by a preliminary experiment. The means for performing A / D conversion, counting digital signals, and counting signal widths may be realized by a program in the calculation unit 37C.

Further, as the displacement vibration detection unit 33, a servomotor motor current signal or motor torque signal or a signal proportional to the motor current signal or motor torque signal is used as a displacement vibration detection signal for detecting displacement vibration. May be good. By using the displacement vibration detection signal in this way, it is possible to determine the start timing of active control without installing a special sensor. Specifically, the displacement vibration detection unit 33 moves the elevating frame 19 shown in FIG. 1 in the horizontal direction. The motor current signal or motor torque signal of the servomotor 13 in the servo mechanism, or the motor current signal or motor torque. A signal proportional to the signal is detected from the servo amplifier 39 as the displacement vibration detection signal S1. If the information on the displacement vibration frequency component is obtained from the signal S1, it is not necessary to provide a special sensor around the take-out mechanism 24 or the mold of the molding machine to detect the horizontal vibration of the take-out head 23. In order to suppress the vibration of the elevating frame 19 in the vertical direction, the motor current signal or the torque signal is acquired from the output of the servo amplifier 39 for driving the motor of the motor that moves the elevating frame 19 in the vertical direction, and the electric actuator 25 is moved. You just have to drive it. In this case, the mounting position of the electric actuator 25 may be changed so that the vibration generated by the electric actuator 25 faces in the vertical direction.

FIG. 6A shows the vibration waveform A and the servomotor measured by a laser displacement meter (a laser displacement meter sold by KEYENCE Co., Ltd. under the product name of IL-S100) of the vibration state of the take-out mechanism 24 during the pull-out operation. It is a waveform diagram displayed so that it can be compared with the torque command waveform B of 13. By the way, the torque command waveform B is taken out from the torque command output terminal of the servo amplifier sold by Fuji Electric Co., Ltd. under the trade name of RYT201D5-LS2-Z25. Comparing the waveform A and the waveform B, it can be seen that the two waveforms A and B are in a proportional relationship when viewed from the peak value, although there is a phase shift. This is as shown in FIG. 6 (B). It was also confirmed from the plot results of the absolute value of the torque command waveform and the absolute value of the output of the laser displacement meter. It has been confirmed that this relationship also appears in the motor current signal of the motor. Focusing on the first peak and the second peak of both waveforms, it can be seen that both waveforms have a rise deviation (advance) of 0.03 to 0.04 seconds.

<Results of combined use of servo motor positioning control and active control>
Hereinafter, the results of confirming the effect of feedback control in the active control device used in the present embodiment will be described with reference to FIGS. 7 to 10. First, FIG. 7 is a comparative example, in which the vibration damping control possessed by the positioning servo device of the servomotor is used (ON) and the vibration damping control is used in addition to the positioning control by the servomotor without performing the active control. It is a figure which shows the plurality of types of waveforms and a partially enlarged waveform from the drawing operation start position of a molded product to the completion of the vibration damping operation when there is no (OFF). In FIG. 7, the waveform of the “servomotor feedback speed” is a feedback speed signal used when positioning control by the servomotor is performed by feedback control. The waveform of the "servomotor command torque" is a torque command used for feedback control. The waveform of the "displacement amount of the head" is the displacement amount of the take-out head 23 detected from the output of the laser displacement meter. Further, the waveform of "acceleration of the elevating frame" is an output waveform of a third acceleration sensor (not shown) that detects the horizontal acceleration provided on the elevating frame 19 for confirmation. Then, in FIG. 7, “section A” is the time from the pull-out operation start position to the pull-out completion. Further, "X1" is a waveform when vibration suppression control is not performed by the positioning servo device of the servomotor (OFF), and "X2" is a waveform when vibration suppression control is performed by the positioning servo device of the servomotor (X1). It is a waveform of ON). As described in the enlarged view, when vibration damping control is performed by the positioning servo device of the servomotor, the amplitude of vibration when the target position is reached is reduced. However, even after the extraction operation is completed, the residual vibration cannot be reliably reduced by the vibration damping control by the positioning servo device of the servomotor.

FIG. 8 is a diagram showing a plurality of types of waveforms and partially enlarged waveforms showing the control results when the positioning control function by the servomotor and the active control are used together (Y2) and when only the active control is performed (Y1). is there. In FIG. 8, “section B” is a section in which active control is actively performed. In this example, active control was positively performed from the end of "section A", that is, when the withdrawal was completed. In "section A", active control is not performed in order to clarify the effect of active control. From FIG. 8, while the amplitude of the displacement vibration of the take-out head 23 is large, it takes time to reduce the displacement vibration (waveform of Y1) only by the active control, and the positioning control by the servomotor and the active control are used together. In the case (Y2), it can be seen that the displacement vibration can be quickly reduced and the residual vibration after reaching the target position can also be reduced.

FIG. 9 shows the control when only the positioning control function by the servomotor is performed (Z1 waveform) and when the positioning control function by the servomotor and the active control are positively used together by using the timer time period (Z2 waveform). It is a plurality of types of waveform diagrams and a partially enlarged waveform diagram showing the results. In this example, the timer time period for determining the timing for actively using the active control by utilizing the maximum output of the electric actuator is set to start the active control in 0.5 seconds from the start of the withdrawal operation. In FIG. 9, the section of “Active ON” is the section in which active control is performed. From FIG. 9, even if the completion of the timer time counting is used as the active control start signal, if the timer time setting is appropriate, the combined effect of the positioning control function and the active control by the servomotor can be surely obtained. I understand.

<Other embodiments>
In the above embodiment, the positioning control is performed and active control of the servo motor together. However, a commercially available servo device for a servo motor has a positioning control function, a vibration damping function for suppressing vibration of a predetermined frequency, and a jerk control function for suppressing an acceleration change rate within a predetermined range. The present invention relates to a positioning servo device when the positioning servo device is configured to perform vibration damping control together with positioning control, and when the positioning servo device is configured to perform jerk control together with positioning control. Of course, it can be applied even when is configured to perform vibration damping control and jerk control together with positioning control.

In the conceptual waveform of FIG. 10, the waveform of A imitates the displacement vibration of the take-out head when only the positioning control is performed by the servo device, and the waveform of B is the positioning control and the vibration suppression control by the servo device. The displacement vibration of the take-out head when used together is imitated, and the waveform of C imitates the displacement vibration of the take-out head when the positioning control, the vibration damping control, and the jerk control are used together in the servo device. In FIG. 10, TH is a threshold set to determine the active start time of active control. In this example, by comparing the amplitudes of the threshold values TH and the waveforms A to C, it is assumed that the active control is positively started after the amplitude is attenuated to the threshold value TH or less. The waveform of A'simulates the displacement vibration of the take-out head when the active control is positively used from time T3 when the positioning control is performed by the servo device, and the waveform of B'is the waveform of the servo device. After performing positioning control and vibration suppression control, the displacement vibration of the take-out head when active control is actively used from time T2 is imitated, and the waveform of C'is controlled by positioning control and control by the servo device. It imitates the displacement vibration of the take-out head when the vibration control and jerk control are used together and the active control is actively used from time T1. From these waveforms, it can be seen that the combined use of various control functions of the servo device and active control is effective. In particular, as you can see by comparing the waveforms A, B and C with the waveforms A', B'and C', if the positioning control of the servo device, the vibration suppression control, the jerk control and the active control are used together, the displacement vibration will be generated at an early stage. Since it can be suppressed, it can be seen that active control can be effectively utilized even with a small electric actuator. The maximum output of the electric actuator is after the amplitude of the displacement vibration of the take-out head 23 is attenuated to a predetermined magnitude by the positioning control, vibration damping control and / or jerk control by the servomotor, or before it can be regarded as attenuated. Limited active control may be performed with lower output.

In the above embodiment, active control is started together with the positioning control function by the servomotor. However, in that case, from the maximum output of the electric actuator until the amplitude of the displacement vibration of the take-out head is attenuated to a predetermined magnitude or can be regarded as attenuated by the positioning control function and active control by the servomotor. Active control is performed with low output. In FIG. 11, the gain of the active control output (actuator drive signal) of the drive signal generation unit 37 is set to 10% until t = 0.4 seconds immediately after the first amplitude of the servomotor feedback speed is generated, and after 0.4 seconds, the gain is set to 10%. It is a waveform diagram for demonstrating the operation when this is realized by setting a gain as 100%.

In the example of FIG. 11, the waveform W1 is a waveform indicating the amount of head displacement when the active control is turned off from the start of the positioning control of the servomotor, and W2 is the waveform showing the active control ON from the start of the positioning control of the servomotor. It is a waveform diagram which shows the head displacement amount at the time of this. In this example, when the active control is turned off (in the case of the waveform W1), only the positioning control function by the servomotor is performed from the beginning to the end. Comparing the case where the active control is OFF and the case where the active control is ON (waveform W2), the active control and the servomotor are performed from the beginning of the control until t = 0.4 seconds immediately after the first amplitude of the servomotor return speed is generated. It can be seen that the vibration damping time can be significantly shortened when used in combination with the positioning control function. If the gain up to t = 0.4 seconds immediately after the first amplitude of the servomotor feedback speed is generated is too large, the positioning control of the servomotor may be adversely affected.

In this example, since the active control is started together with the positioning control function by the servomotor, it is possible to smoothly shift from the vibration damping control by the positioning control by the servomotor to the vibration damping by the active control. As a result, the displacement vibration of the take-out head can be smoothly suppressed in a shorter time than before by using a lightweight and compact electric actuator. The "low output" is preferably set so as not to affect the positioning control by the servomotor. In this case, it is preferable that the active controller gradually or gradually increases the output of the electric actuator from a low output. In this way, it is possible to prevent the rise of the active control from adversely affecting the vibration damping control.

FIG. 12 shows the results of tests on three types of patterns in which the output conditions of the active control are changed when the servomotor performs the vibration damping by the active control without performing the vibration damping control. Pattern A is a pattern in which active control is performed at the maximum output (steady output) of 100% from the beginning of active control, and Pattern B is a stepwise output of active control from 1% → 20% → 55% → 100%. Pattern C is a pattern in which the output of the active control is gradually and continuously performed from 0% to 100%. The waveform V1 is a waveform when active control is not performed, waveform V2 is a waveform when active control is performed by Pattern A, and waveform V3 is a waveform when active control is performed by Pattern B. Waveform V4 is a waveform when active control is performed by Pattern C. From this result, when the active control is performed with 100% output in Pattern A from the beginning, the initial vibration amplitude is increased, which adversely affects the vibration damping. On the other hand, it can be seen that the vibration damping is faster when the output is gradually increased like Pattern B or when the output is gradually and continuously increased like Pattern C.

In addition, when the amplitude of the displacement vibration is considered to have been attenuated to a predetermined magnitude, the active control device receives an ejector backward limit signal, an ejector forward limit signal, a mold opening / closing signal, and a mold opening from the molding machine. It may be operated when a limiting signal or a mold closing signal is output. The time when the ejector backward limit signal, ejector forward limit signal, mold opening / closing signal, mold opening signal or mold closing signal from the molding machine is generated is completed after the start time of the positioning control by the servomotor. It is issued before the command is output. Therefore, as the operation start timing of the active control device, an ejector backward limit signal, an ejector forward limit signal, a mold opening / closing signal, a mold opening signal, or a mold closing signal from the molding machine can be used. In this way, the ejector backward limit signal, ejector forward limit signal, mold opening / closing signal, mold opening signal, or mold closing signal transmitted from the molding machine side to the molded product ejecting machine side are used as the operation start timing. Then, since it is not necessary to prepare special signal processing, a timer, or the like for timing determination, the configuration of the active control device becomes simple.

Further, the active control device 31 may be in an operating state when the take-out mechanism 24 stops at the molded product open position RP as shown in FIG. By doing so, it is possible to prevent deformation of the molded product that has not yet been completely cured. Then, the molded product open position RP may be provided with a displacement sensor 26 that detects the transverse displacement vibration when the take-out mechanism 24 is displaced and vibrated in the transverse direction orthogonal to the left-right direction and the vertical direction. In this case, the active control device 31 is configured to further mount an electric actuator (not shown) that suppresses the transverse displacement vibration based on the output of the displacement sensor 26 on the take-out mechanism 24 to perform active control. In this way, most of the vibration applied to the molded product when the molded product is opened can be suppressed.

According to the present invention, since active control is used in combination with at least positioning control of the positioning servo device , displacement vibration of the attachment can be suppressed in a shorter time than before. Further, when the positioning control function of the servo device and the active control are used together, a small and lightweight electric actuator can be used as compared with the case where the active control alone controls the vibration.

1 Molded product take-out machine 3 Traverse frame 5 Traveling body 8 Runner lifting unit 9 Molded product suction lifting unit 11 AC servomotor 13 Servomotor 15 Belt 17 Running body 18 Drive source 19 Lifting frame 21 Reversing unit 23 Extraction head 24 Extraction mechanism 25 Electric actuator 26 Displacement sensor 27 Acceleration sensor 31 Active controller 33 Displacement vibration detection unit 34 Phase correction unit 35 Additional vibration detection unit 37 Drive signal generation unit 37A 1st gain adjustment unit 37B 2nd gain adjustment unit 37C Calculation unit 38 Acceleration sensor 39 Servo amplifier

Claims (15)

A molded product take-out machine equipped with an attachment to the approach frame controlled by a positioning servo device that uses a servomotor.
A displacement vibration detection unit that detects the displacement vibration of the attachment,
It is a molded product take-out machine provided with an active control device that applies active control that suppresses the displacement vibration of the attachment by adding the vibration of the opposite phase to the displacement vibration detected by the displacement vibration detection unit from the electric actuator to the attachment. hand,
The active control device starts the active control together with at least the positioning control of the positioning servo device, but until the amplitude of the displacement vibration is attenuated to a predetermined magnitude or can be regarded as attenuated. A molded product take-out machine characterized in that active control is performed with an output lower than the maximum output of the electric actuator. The molded product take-out machine according to claim 1, wherein the positioning servo device is configured to perform vibration damping control together with the positioning control. The molded product take-out machine according to claim 1, wherein the positioning servo device is configured to perform jerk control together with the positioning control. The molded product take-out machine according to claim 1, wherein the positioning servo device is configured to perform vibration damping control and jerk control together with the positioning control. The entry frame is an elevating frame provided on the pull-out frame.
The attachment is a take-out head provided at the tip of the elevating frame.
The molded product take-out machine according to any one of claims 1 to 4, wherein the active control is executed when the pull-out frame is driven to perform a pull-out operation. The molded product taking out according to claim 1, wherein the active control device determines that the amplitude of the displacement vibration is attenuated to a predetermined magnitude by comparing the output of the displacement vibration detection unit with a threshold value. Machine. When the active control device is in a state where it can be considered that the amplitude of the displacement vibration has been attenuated to a predetermined magnitude, a predetermined timer time has elapsed from a predetermined operation time in the positioning control by the servomotor. The molded product take-out machine according to claim 1, wherein the determination is made. The predetermined operation time is either the start time of the positioning control by the servomotor, when the completion command is output, or before or after the completion command is output.
The molded product take-out machine according to claim 7, further comprising a timer time timing adjusting unit for adjusting the timer time. When the amplitude of the displacement vibration is considered to have been attenuated to a predetermined magnitude, the active control device receives an ejector backward limit signal, an ejector forward limit signal, a mold opening / closing signal, and a mold from the molding machine. The molded product take-out machine according to claim 1, wherein the opening signal or the mold closing signal is output. In the active control device, when the take-out head needs to position the take-out head after taking out the molded product from the mold of the molding machine, it can be considered that the amplitude of the displacement vibration is attenuated to a predetermined magnitude. The molded product unloading machine according to claim 5 , wherein the time is determined based on a signal output from a peripheral device of the molded product unloading machine. The displacement vibration detection unit outputs a motor current signal of the servomotor or a torque signal of the motor or a signal proportional to the motor current signal or the torque signal of the motor as a displacement vibration detection signal for detecting the displacement vibration. Using
The molded product take-out machine according to claim 1, wherein the active control device determines that the amplitude of the displacement vibration has been attenuated to a predetermined magnitude based on the displacement vibration detection signal. The active control device digitally obtains when the displacement vibration detected by the displacement vibration detection unit is A / D converted when the amplitude of the displacement vibration is considered to have been attenuated to a predetermined magnitude. The molded product unloading machine according to claim 1, wherein the determination is based on the number of signals or a change in the signal width of the digital signal. The take-out head is attached to the tip of the elevating frame attached to the moving base provided on the pull-out frame so that it can be moved freely via the belt transmission mechanism or the rope transmission mechanism driven by the servomotor.
A displacement vibration detection unit that detects the displacement vibration of the take-out head,
A molded product take-out machine provided with an active control device that applies an vibration in a phase opposite to the displacement vibration detected by the displacement vibration detection unit from the electric actuator to the take-out head and performs active control to suppress the displacement vibration of the take-out head. And
The active control device starts the active control together with the positioning control by the servomotor, but the amplitude of the displacement vibration of the take-out head reaches a predetermined magnitude by the positioning control function by the servomotor and the active control. A molded product take-out machine characterized in that the active control is performed at an output lower than the maximum output of the electric actuator until it is attenuated or until it can be regarded as attenuated. The molded product take-out machine according to claim 13, wherein the low output does not affect the positioning control by the servomotor. The molded product take-out machine according to claim 13 or 14, wherein the active control device gradually or gradually increases the output of the electric actuator from the low output.

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