JP6038015B2 - Servo control device - Google Patents

Description

  The present invention relates to a servo control device applied to a processing apparatus that processes a long workpiece while conveying it.

  Traditionally, to automate the work of printing, crimping, cutting, or perforating a long workpiece (eg paper or film), A processing apparatus that processes at a predetermined interval is used. Marks are printed on the workpiece at predetermined intervals, and the processing apparatus performs processing using a tool (for example, a blade) with a position (mark position) where the mark is printed as a target position. The tool is mounted on the processing roll. The processing apparatus can perform periodic processing on the workpiece by rotating the processing roll while conveying the workpiece. Hereinafter, a workpiece conveyed by such a processing apparatus may be referred to as a conveyance material.

  A servo control device is used to drive the processing roll so that the tool processes the mark position. The position on the conveying material actually processed by the tool is referred to as a processing position. Here, the mark position and the processing position may be shifted due to various factors. Factors that cause the mark position to deviate from the processing position include, for example, mark printing errors, mark position fluctuations due to the expansion and contraction of the transport material, transport speed errors due to the diameter error of the transport roll that transports the transport material, transport roll or processing Examples include roll eccentricity, fluctuations in the speed of a motor that drives the conveyance roll or processing roll (speed ripple, cogging torque), fluctuations in conveyance speed or mark position due to fluctuations in tension applied to the conveyance material, and the like.

  In this regard, Patent Document 1 discloses a technique for controlling the rotational phase of a magnetic head drum of a video tape recorder. According to this technique, the phase control of the drum motor is executed based on the phase error calculated from the reference pulse and the feedback phase control pulse. Then, the rotational speed of the drum motor is corrected based on the DC phase error obtained by smoothing the phase error, thereby realizing correction of the phase error that occurs in the steady state.

  Patent Document 2 discloses a technique for detecting a deviation state using a mark and performing correction using a correction function based on the detected deviation state. The correction function is a function that adds a correction amount that changes sequentially with time to the basic function.

JP 59-38804 A Special Table 2004-530207

  However, when the techniques of Patent Documents 1 and 2 are applied, there are various cases in which the conveyance speed and the peripheral speed of the machining roll at the moment of machining are different, or due to a synchronization shift between the conveyance roll and the machining roll. Problems arise. For example, when the tool is a blade, the conveying material is caught on the blade or the conveying material is lifted. Thereby, disorder of a processing surface or a fracture of a conveyance material occurs. Further, the tension applied to the conveying material fluctuates due to the reaction when the conveying material and the blade are separated, and as a result, the subsequent processing quality or operational stability is adversely affected.

  The present invention has been made in view of the above, and an object of the present invention is to obtain a servo control device that realizes as high-quality processing and operational stability as possible on a long workpiece.

In order to solve the above-described problems and achieve the object, the present invention provides a transport roll for transporting a long transport material in which marks that are target positions for processing are applied at predetermined intervals, and the transport material A servo control device applied to a machine tool comprising: a processing roll including a tool for processing a workpiece; and a sensor disposed on a transport path of the transport material and detecting the passage of the mark. A processing roll control for rotating the processing roll based on a transport roll control unit that rotates in synchronization with the main shaft operation, an operation function that defines a relationship between the main shaft operation and the main shaft operation and the operation of the processing roll. And a processing roll control unit that calculates a distance error between the marks based on a detection signal of the sensor, and a tool for processing by the tool in one rotation of the processing roll. A second section that is different from the first section in accordance with an error in the interval so that the peripheral speed of the transport roll and the peripheral speed of the processing roll are equal in a first section including a gap. A first correction unit that changes the operation function so that the processing roll makes one rotation while being conveyed by a distance of an interval between the marks by accelerating and decelerating, and the processing roll control unit includes: A determination unit that determines whether the error in the interval is larger than a threshold value, and a second correction unit that corrects an input value to the operation function by an amount corresponding to the error in the interval. When it is determined that the error in the interval is larger than the threshold, the first correction unit changes the operation function, and when it is determined that the error in the interval is smaller than the threshold. The second correction unit inputs the input Correcting the, characterized in that.

  According to the present invention, since control is executed so that the peripheral speed of the transport roll and the peripheral speed of the processing roll are equal at the moment of processing, high-quality processing can be performed on a long workpiece. Can do.

FIG. 1 is a diagram illustrating a configuration of a machining apparatus in which the servo control apparatus according to the first embodiment is used. FIG. 2 is a diagram illustrating a configuration of the servo control device. FIG. 3 is a diagram illustrating a configuration of the cam correction unit according to the first embodiment. FIG. 4 is a diagram showing a cam pattern calculated by the cam data changing means. FIG. 5 is a diagram showing the peripheral speed of the processing roll. FIG. 6 is a diagram for explaining the positional relationship among the mark sensor, the mark position, and the processing position on the conveyance path. FIG. 7 is a diagram for explaining the positional relationship among the mark sensor, the mark position, and the processing position on the conveyance path. FIG. 8 is a diagram showing various timings when neither the machining axis cam input is corrected nor the cam data is changed. FIG. 9 is a diagram showing various timings when the machining axis cam input is corrected. FIG. 10 is a diagram illustrating various timings when the cam data is changed. FIG. 11 is a diagram illustrating an example of the transition of the mark length error when the comparative example is applied and when the first embodiment is applied. FIG. 12 is a diagram illustrating a configuration of the cam correction unit according to the second embodiment.

  Hereinafter, a servo control device according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a diagram illustrating a configuration of a machining apparatus in which the servo control apparatus according to the first embodiment is used. The processing apparatus 100 includes a mark sensor 4, a processing roll 5, a processing motor 7, a transport roll 8, a transport motor 9, and a servo control device 1. The processing apparatus 100 cuts the conveying material 2 on which the marks 3 are printed at a predetermined interval with the blade 6 that is a tool while conveying the conveying material 2 in the right direction in the drawing. The transport motor 9 drives a transport roll 8 for transporting the transport material 2. The processing motor 7 rotates the processing roll 5 to which the blade 6 is attached. The blade 6 is rotated by the processing roll 5 and can process the contact position on the conveying material 2. A plurality of transport rolls 8 may be provided along the transport path.

  The mark sensor 4 is disposed on the conveyance path of the conveyance material 2. The mark sensor 4 detects the mark 3 printed on the conveying material 2 and transmits a mark detection signal S (k) indicating whether or not the mark 3 has been detected to the servo control device 1. For example, the mark sensor 4 transmits a notification indicating “On” as the mark detection signal S (k) from when the mark 3 starts to pass through the position where the mark sensor 4 is disposed until the end of the passage. After the passing of the mark 3, the notification indicating “Off” is transmitted as the mark detection signal S (k).

  Note that k is a parameter provided for the following explanation. k is incremented every time the mark sensor 4 detects the mark 3. Hereinafter, the cycle in which the mark sensor 4 detects the mark 3 is referred to as a detection cycle. Further, the interval between the marks 3 is expressed as a mark length.

  The servo control device 1 drives the processing motor 7 and the conveyance motor 9. Here, the servo control device 1 controls the drive of the machining motor 7 based on the mark detection signal S (k) so that the mark position matches the machining position.

  FIG. 2 is a diagram illustrating a configuration of the servo control device 1. As shown in the figure, the servo control device 1 includes a reference command generation unit 11, a gain unit 12, a cam calculation unit 13, a conversion unit 14, a drive control unit 15, a gain unit 16, a subtraction unit 17, a cam calculation unit 18, and a conversion unit. 19, drive control means 20, and cam correction means 21.

  The gain unit 12, the cam calculation unit 13, the conversion unit 14, and the drive control unit 15 cooperate to function as a transport roll control unit that rotates the transport roll in synchronization with the spindle operation. Further, the gain means 16, the subtraction means 17, the cam calculation means 18, the conversion means 19, the drive control means 20, and the cam correction means 21 are operations that define the main shaft operation and the relationship between the main shaft operation and the operation of the processing roll 5. It functions as a processing roll controller that rotates the processing roll 5 based on the function.

  The reference command generator 11 generates a reference command xr (t). The reference command xr (t) represents the position of the spindle that serves as a reference for synchronizing the machining motor 7 and the transport motor 9. The main axis may be virtual. The reference command xr (t) may be generated, for example, in the form of an encoder pulse that indicates the position of the spindle. The servo control device 1 may be supplied with the reference command xr (t) from the outside. Further, the reference command xr (t) is not limited to only one indicating the position as long as it indicates the spindle operation.

  The gain unit 12 multiplies the reference command xr (t) by the gain G2 and outputs the transport axis reference command xr2 (t). The transport axis reference command xr2 (t) is input to the cam calculation means 13 as the transport axis cam input x2 (t).

  The cam calculation means 13 converts the conveyance axis cam input x2 (t) into a conveyance axis cam output y2 (t) based on the cam data. The cam data used by the cam calculation means 13 is an operation function that defines the relationship between the spindle operation and the operation of the transport roll 8. Here, specifically, the cam data includes a cam input length X2, a cam output length Y2, and a cam pattern f2 (x). The cam pattern f2 (x) is an operation function that defines the relationship between the conveyance axis cam input x2 (t) and the conveyance axis cam output y2 (t). The cam pattern f2 (x) is information expressed using, for example, a table or a mathematical expression.

  The converting means 14 converts the transport shaft cam output y2 (t) into a transport shaft position command yr2 (t) that is a position command for the transport motor 9.

  The drive control unit 15 receives a conveyance shaft position ym <b> 2 (t) that is a detection position of the conveyance motor 9 from the conveyance motor 9. The drive control unit 15 controls the torque of the transport motor 9 so that the transport shaft position command yr2 (t) and the transport shaft position ym2 (t) coincide.

  The gain means 16 multiplies the reference command xr (t) by the gain G1 and outputs the machining axis reference command xr1 (t).

  The subtracting means 17 subtracts the cam input correction dX1 (k) calculated by the cam correcting means 21 from the machining axis reference command xr1 (t). The result of subtraction by the subtracting means 17 is input to the cam calculating means 18 as a machining axis cam input x1 (t).

  The cam calculation means 18 converts the machining axis cam input x1 (t) into the machining axis cam output y1 (t) based on the cam data. The cam data used by the cam calculation means 18 is an operation function that defines the relationship between the spindle operation and the operation of the processing roll 5. Specifically, the cam data includes a cam input length X1, a cam output length Y1, and a cam pattern f1 (x). The cam pattern f1 (x) is information expressed using, for example, a table or a mathematical expression. Here, the cam calculation means 18 is configured so that the setting of the cam data can be changed. The cam data is changed by the cam correction means 21.

  The conversion means 19 converts the machining axis cam output y1 (t) into a conveyance axis position command yr1 (t) that is a position command for the machining motor 7.

  The drive control means 20 receives a machining axis position ym1 (t), which is a detection position of the machining motor 7, from the machining motor 7. The drive control means 20 controls the torque of the machining motor 7 so that the machining axis position command yr1 (t) matches the machining axis position ym1 (t).

  The cam correction means 21 receives the mark detection signal S (k) and the monitor data U (t). The cam correction means 21 holds (latches) the monitor data U (t) at the timing when the passage of the mark 3 is detected. The cam correction unit 21 calculates the correction amount of the machining axis cam input x1 (t) based on the held monitor data U (t) so that the mark position matches the machining position. The cam correction means 21 outputs the calculated correction amount of the machining axis cam input x1 (t) as the cam input correction dX1 (k). Further, the cam correction means 21 can change the cam pattern f1 (x) and the cam input length X1 in the cam data set in the cam calculation means 18.

  Note that any data can be adopted as the monitor data U (t) as long as the amount of movement of the conveying material 2 can be derived. For example, the reference command xr (t), the conveyance axis cam input x2 (t), the conveyance axis cam output y2 (t), the conveyance axis position command yr2 (t), or the conveyance axis position ym2 (t) is the monitor data U (t ). Here, as an example, it is assumed that the reference command xr (t) is used as the monitor data U (t).

  FIG. 3 is a diagram illustrating a configuration of the cam correction unit 21 according to the first embodiment. The cam correction unit 21 includes a mark length error calculation unit (first calculation unit) 22, a correction value calculation unit 23, a holding unit 24, a cam input correction unit 25, and a cam data change unit 26. The correction value calculation means 23 and the cam data change means 26 work together to function as a first correction unit that changes cam data. Further, the correction value calculation means 23 and the cam input correction means 25 function as a second correction unit that corrects the machining axis cam input x1 (t) in cooperation.

  The holding unit 24 holds the monitor data U (t) using the mark detection signal S (k) as a latch signal, and outputs the held monitor data U (t) as latch data U (k).

  The mark length error calculation means 22 calculates the mark length error based on the mark detection signal S (k). Specifically, the mark length error calculation unit 22 includes a delay unit 27, a subtraction unit 28, a subtraction unit 29, a delay unit 30, and an error storage unit 31. The delay means 27 outputs the latch data U (k−1) output from the holding means 24 in the previous detection cycle. The subtracting unit 28 subtracts the latch data U (k−1) of the previous detection cycle output from the delay unit 27 from the latch data U (k) output from the holding unit 24 in the current detection cycle. The subtraction means 28 outputs the value dU (k) obtained by the subtraction as a mark length calculation value L (k) that is a calculation value of the mark length.

  The delay means 30 outputs the cam input length change value X1 (k-1) of the previous detection cycle output from the adding means 35 described later as a mark length reference value LP (k) which is a mark length reference value. . The subtracting means 29 subtracts the mark length reference value LP (k−1) from the mark length calculated value L (k) and outputs the value obtained by the subtraction as the mark length error dL (k). The error storage means 31 holds and outputs the mark length error dL (k).

  The correction value calculation unit 23 includes a switching unit 32, a determination unit 33, a gain unit 34, and an addition unit 35. The determination unit 33 compares the absolute value of the mark length error dL (k) with a preset threshold value dXs, and inputs the determination result to the switching unit 32 as a selection signal. The switching unit 32 switches the output destination of the mark length error dL (k) between the gain unit 34 and the addition unit 35 based on the selection signal.

  When the absolute value of the mark length error dL (k) is smaller than the threshold value dXs, the determination unit 33 selects the gain unit 34 as the output destination of the mark length error dL (k). The gain means 34 multiplies the mark length error dL (k) by the gain Q, and outputs the value obtained by the multiplication as the cam input correction dX1 (k). The cam input correction unit 25 inputs the cam input correction dX1 (k) to the subtraction unit 17 in the asynchronous section of one rotation of the processing roll 5. The input of the cam input correction dX1 (k) to the subtraction means 17 can be executed at an arbitrary timing in the asynchronous period.

  In the first embodiment, the peripheral speed of the work roll 5 and the peripheral speed of the transport roll 8 are matched in a predetermined section including the moment when the blade 6 processes the transport material 2. A section in which the peripheral speed of the processing roll 5 and the peripheral speed of the transport roll 8 are matched is referred to as a synchronous section (first section). The asynchronous section refers to a section (second section) excluding the synchronous section. That is, the asynchronous section is a predetermined section in which the blade 6 does not contact the conveying material 2. Whether the current time is a synchronous zone or an asynchronous zone can be determined, for example, by the rotation angle of the processing roll 5 at that time.

  When the absolute value of the mark length error dL (k) is larger than the threshold value dXs, the determination unit 33 selects the addition unit 35 as the output destination. The adding means 35 adds the mark length error dL (k) to the cam input length Xn set in the cam calculating means, and outputs the value obtained by the addition as the cam input length change value X1 (k). The cam data changing means 26 calculates a cam pattern f1 (x) suitable for the cam input length change value X1 (k). The cam input length change value X1 is equal to the mark length calculation value L (k). Accordingly, the cam data changing unit 26 calculates a new cam pattern f1 (x) so that the processing roll 5 makes one rotation while the conveying material 2 is conveyed by a distance equal to the mark length calculation value L (k). . The cam data changing means 26 uses the cam pattern f1 (x) and the cam input length X1 set in the cam calculating means 18 as the newly calculated cam pattern f1 (x) and the cam input length change value X1 (k). Update. The cam data changing unit 26 changes the cam pattern f1 (x) and the cam input length X1 in the synchronization period. The cam input length change value X1 (k) can be changed at any timing within the synchronization interval.

  Here, the cam data changing operation by the cam data changing means 26 will be described in detail. In order to simplify the explanation, the cam calculation means 13 for the transport shaft has a linear cam indicating that the relationship between the transport shaft cam input x2 (t) and the transport shaft cam output y2 (t) is a linear relationship. As a result, the conveyance speed of the conveyance material 2 is assumed to be constant. The gear ratio between the processing roll 5 and the processing motor 7 and the gear ratio between the transport roll 8 and the transport motor 9 are both “1”. Further, it is assumed that the gain G2 of the gain unit 12 and the gain G1 of the gain unit 16 are both “1”.

  As described above, in the cam calculation means 18, based on the cam data defined by the cam pattern f1 (x), the cam input length X1, and the cam output length Y1, the machining axis cam output y1 with respect to the machining axis cam input x1 (t). (T) is calculated. For example, the unit of the machining axis cam input x1 (t) is deg, the cam output length Y1 is set to 360 deg, and the cam input length X1 is set to a value corresponding to the mark length Lm. Specifically, when the unit of the machining axis cam input x1 (t) is a unit of length such as mm, Xb = Lm may be set. Further, when the unit of the machining axis cam input x1 (t) is a pulse and the length of one pulse machining axis cam input x1 (t) corresponds to 10,000 pulses in the reference command xr (t), Xb = It may be set to 10000 * Lm. Here, it is assumed that Xb = Lm. Further, when the machining shaft cam input x1 (t) is moved by Lm, the machining motor 7 is moved by 360 degrees (that is, rotated once), and the machining roll 5 is also rotated once. In addition, the conveyance axis cam input x2 (t), the conveyance motor 9, and the conveyance roll 8 are assumed to have the same relationship as the machining axis cam input x1 (t), the machining motor 7, and the machining roll 5.

  FIG. 4 is a diagram showing a cam pattern calculated by the cam data changing means 26. FIG. 5 is a diagram showing the peripheral speed of the processing roll 5 corresponding to each of the three cam patterns shown in FIG.

  In the steady state, the conveying material 2 is conveyed at a constant speed, but the mark length Lm varies due to the various factors described above. When the mark length Lm is equal to the circumferential length L1 of the processing roll 5 (Lm = L1), the cam pattern for rotating the processing roll 5 is similar to the cam pattern for rotating the transporting roll 8. A linear cam for rotating the processing roll 5 at the same peripheral speed as the peripheral speed and always at a constant peripheral speed is applied (see case b). X1b is the machining shaft cam input length in case b.

  When the mark length Lm is smaller than the peripheral length L1 of the processing roll 5 (Lm <L1), when the processing roll 5 is rotated at the same peripheral speed as the peripheral speed of the transport roll 8 and always at a constant peripheral speed, The mark position does not match. In order to make the machining position coincide with the mark position, a cam pattern that speeds up the peripheral speed of the machining roll 5 in the asynchronous period is set (see case a). That is, the peripheral speed of the work roll 5 is increased by acceleration / deceleration compared to the case a. In the synchronization period, new cam data is calculated so that the peripheral speed of the processing roll 5 matches the peripheral speed of the transport roll 8. X1a is the machining shaft cam input length in case a.

  When the mark length Lm is larger than the peripheral length L1 of the processing roll 5 (Lm> L1), the peripheral speed of the processing roll 5 is set to an asynchronous period compared to the cam pattern of the case b in order to match the processing position with the mark position. A slow cam pattern is calculated (see case c). X1c is the machining shaft cam input length in case c.

  In the transport path, the position where the mark sensor 4 is disposed and the position where the blade 6 processes the transport material 2 are separated by an integer multiple of the mark length. There are cases where the position where the mark sensor 4 is disposed, the position where the blade 6 processes the conveying material 2 and the integer multiple of the mark length do not exactly match. Because there may be.

  6 and 7 are diagrams for explaining the positional relationship among the mark sensor 4, the mark position, and the processing position on the conveyance path. The mark position in the kth detection cycle is denoted as A [k]. FIG. 6 shows the positional relationship at the detection timing of A [k], and FIG. 7 shows the positional relationship at the processing timing of A [k]. Here, it is assumed that the position where the mark sensor 4 is disposed and the position where the blade 6 processes the conveying material 2 are separated by a distance approximately equal to the mark length. As shown in FIGS. 6 and 7, the processing timing of A [k] is delayed by a time approximately equal to the detection cycle from the detection timing of A [k]. When the position where the mark sensor 4 is disposed and the position where the blade 6 processes the conveying material 2 are separated by an integer multiple of the mark length, the processing timing of A [k] is A [k ] Is delayed by a time approximately equal to an integral multiple of the detection cycle. In FIG. 7, for example, due to an error in the mark length, the position where the mark is printed, that is, the position A [k] to be originally processed and the actual processing position B [k] are shown. Does not match.

  FIG. 8 is a diagram showing various timings when neither the machining axis cam input x1 (t) is corrected nor the cam data is changed. The horizontal axis indicates the elapsed time [s], and the vertical axis indicates the rotational position [deg] of the processing roll 5. It is assumed that the blade 6 processes the conveying material 2 when the rotational position of the processing roll 5 reaches an integral multiple of 360 deg. Further, from the time when the mark A [k−1] detected by the mark sensor 4 reaches the position of the processing roll 5 to the time when the mark A [k] detected next reaches the position of the processing roll 5. A time interval is denoted as interval [k]. Note that the time of the section [k] is equal to the kth detection cycle.

  In the section [k-1], the rotation period of the processing roll 5 and the detection period coincide with each other, so that A [k-1] and B [k-1] coincide with each other. If the mark length of the section [k] is larger than the mark length of the section [k−1], the detection period in the section [k] is increased by dT from the detection period in the section [k−1]. In the section [k], the rotation period of the processing roll 5 and the detection period do not coincide with each other, so that the positions of A [k] and B [k] are shifted. Further, since the mark length in the section [k + 1] is further increased from the mark length in the section [k], the detection period in the section [k + 1] is further increased by dT than the detection period in the section [k]. Therefore, the shift amount between A [k + 1] and B [k + 1] is larger than the shift amount between A [k] and B [k].

  FIG. 9 is a diagram showing various timings when the machining axis cam input x1 (t) is corrected. In addition, the dashed-dotted line has shown the relationship demonstrated in FIG. In the interval [k], it corresponds to the difference between the mark length L (k−1) calculated at the detection timing of A [k−1] and the mark length L (k) calculated at the detection timing of A [k]. The cam input is corrected to be delayed by the amount to be changed, and the machining position is changed from B [k] to B ′ [k]. As a result, the rotation period and the detection period of the processing roll 5 coincide with each other in the section [k], and the timing at which A [k] passes through the processing roll 5 coincides with the processing timing. The coincidence of the timing when A [k] passes the machining roll 5 and the machining timing is synonymous with the coincidence of the mark position A [k] and the machining position. C [k] represents the timing at which the cam input is corrected. Here, the cam input is corrected at the timing when the rotational position of the processing roll 5 reaches the asynchronous section. B ′ [k] indicates the corrected machining position. Similarly, in the section [k + 1], the cam input is corrected at the timing C [k + 1], and as a result, the A [k + 1] and the machining position B ′ [k + 1] coincide with each other.

  FIG. 10 is a diagram illustrating various timings when the cam data is changed. As shown in the figure, in the interval [k], the mark length L (k−1) calculated at the detection timing of A [k−1] and the mark length L (k) calculated at the detection timing of A [k] The cam pattern fn (x) and the cam input length Xn are generated so that the cam input is delayed by an amount corresponding to the difference between them, and applied at the timing C [k]. Thereby, in the section [k], the rotation cycle of the processing roll 5 coincides with the detection cycle, and as a result, the mark position A [k] and the processing position B ′ [k] match. In the section [k + 1], A [k + 1] and the machining position B ′ [k + 1] can be matched without changing the cam pattern fn (x) and the cam input length Xn.

  As described above, according to the first embodiment, the servo control device 1 determines that the peripheral speed of the transport roll 8 and the peripheral speed of the processing roll 5 are in the synchronous section including the processing instant of one rotation of the processing roll 5. The processing roll 5 is rotated once so that the processing roll 5 is rotated by an amount corresponding to the mark length by accelerating / decelerating the processing roll 5 in the asynchronous section in accordance with the mark length error. Change the cam data. Since the control is executed so that the peripheral speed of the transport roll 8 and the peripheral speed of the processing roll 5 are equal in the synchronous section, the peripheral speed of the transport roll 8 and the peripheral speed of the processing roll 5 are different in the synchronous section. In comparison, the processed surface of the conveying material 2 can be kept in high quality. That is, it is possible to perform as high-quality processing as possible on a long workpiece. Moreover, the reaction at the time of the conveyance material 2 and the blade 6 separating can be reduced.

  The servo control device 1 changes the cam data when the mark length error is larger than the threshold value dXs, and corrects the machining axis cam input x1 (t) when the mark length is smaller than the threshold value dXs. To do.

  FIG. 11 shows an embodiment in which only the correction of the machining axis cam input x1 (t) can be executed (comparative example) and the correction of the machining axis cam input x1 (t) and the change of the cam data are executed. 1 is a diagram illustrating an example of a transition of a mark length error. According to the comparative example, when the mark length error dL (k) exceeds the threshold value dXs, the correction amount by the cam input correction is large, and every time the mark length error dL (k) exceeds the threshold value dXs. Then, the correction of the large correction amount is executed. When the correction amount by the cam input correction is large, the behavior of the motor by the correction is large, so that the variation in correction becomes large, and the sound and impact generated in the processing apparatus 100 increase. On the other hand, according to the first embodiment, the cam data is changed when the mark length error dL (k) reaches the threshold value dXs. After the cam data is changed, the correction amount by the cam input correction is reduced as compared with the case where the cam data is not updated. Therefore, according to the first embodiment, it is possible to reduce the variation in correction and to reduce the sound and the impact as compared with the case where the cam data is not changed.

  In the above description, the linear cam is set in the cam calculation means 13 so that the conveying material 2 is conveyed at a constant speed. The cam data changing means 26 accelerates or decelerates the processing roll 5 in the asynchronous section according to the mark length error so that the peripheral speed of the transport roll 8 and the peripheral speed of the processing roll 5 become equal in the synchronous section. As long as it is possible to change the cam data of the processing roll 5 so that the processing roll 5 makes one rotation when it is conveyed by the mark length by the cam, the cam calculation means 13 has a cam pattern other than the linear cam. The first embodiment can be applied even when is set.

Embodiment 2. FIG.
FIG. 12 is a diagram showing another configuration example of the cam correction unit. The same constituent elements as those of the first embodiment are denoted by the same reference numerals and names as those of the first embodiment, and redundant description is omitted.

  The cam correction unit 21a according to the second embodiment includes a mark length error calculation unit 22, a correction value calculation unit 23a, a holding unit 24, a cam input correction unit 25, and a cam data change unit 26. The mark length error calculation unit 22 includes a delay unit 27, a subtraction unit 28, a subtraction unit 29, a delay unit 30, and an error storage unit 31.

  The correction value calculation unit 23a includes a switching unit 32a, a determination unit 33a, a gain unit 34a, an addition unit 35, and a subtraction unit 36. The determination unit 33a compares the absolute value of the mark length error dL (k) with a preset threshold value dXs, and inputs the determination result to the switching unit 32a as a selection signal. The switching unit 32a switches between the mark length error dL (k) and the zero value as the cam input length correction value dX (k) input to the adding unit 35 based on the selection signal.

  When the absolute value of the mark length error dL (k) is smaller than the threshold value dXs, the determination unit 33a selects the zero value as the cam input length correction value dX (k). The adding means 35 outputs a value obtained by adding a zero value to the cam input length X1 set in the cam calculating means as the cam input length change value X1 (k). That is, when the absolute value of the mark length error dL (k) is smaller than the threshold value dXs, the cam input length change value X1 (k) is not changed, so that the cam data is not changed. On the other hand, the gain unit 34a multiplies the mark length error dL (k) by the gain Q. The subtracting means 36 subtracts the zero value output from the switching means 32 from the mark length error dL (k) multiplied by the gain Q, and outputs the value obtained by the subtraction as the cam input correction value dX1 (k). To do.

  That is, when the absolute value of the mark length error dL (k) is smaller than the threshold value dXs, the machining axis cam input x1 (t) is corrected and the cam data is changed as in the first embodiment. I will not.

  When the absolute value of the mark length error dL (k) is larger than the threshold value dXs, the determination unit 33a selects the mark length error dL (k) as the cam input length correction value dX (k). The adding means 35 adds the mark length error dL (k) as the cam input length correction value dX (k) to the cam input length X1 set in the cam calculating means, and the value obtained by the addition is added to the cam input length. The change value X1 (k) is output. On the other hand, the gain unit 34a multiplies the mark length error dL (k) by the gain Q. The subtracting unit 36 subtracts the mark length error dL (k) output from the switching unit 32a from the mark length error dL (k) multiplied by the gain Q. The subtracting means 36 outputs the value obtained by the subtraction as the cam input correction value dX1 (k).

  Here, when the gain Q is “1”, as in the first embodiment, the machining axis cam input x1 (t) is not corrected and the cam data is changed. When the gain Q is different from “1”, both the machining axis cam input x1 (t) is corrected and the cam data is changed. In this case, a part of the necessary correction amount can be dealt with by changing the cam data, so that the correction amount of the machining axis cam input x1 (t) can be reduced.

  The constituent elements of the servo control device 1 according to the first and second embodiments (reference command generation means 11, gain means 12, cam calculation means 13, conversion means 14, drive control means 15, gain means 16, subtraction means 17, cam Calculation means 18, conversion means 19, drive control means 20, holding means 24, cam input correction means 25, cam data change means 26, delay means 27, subtraction means 28, subtraction means 29, delay means 30, and error storage means 31 , Switching means 32, switching means 32a, determination means 33, determination means 33a, gain means 34, gain means 34a, addition means 35, and subtraction means 36) are part or all of software, hardware, or both It can be realized by a combination of The realization of a constituent element by software means that the function of the constituent element is realized by executing a program built in a storage device in advance by a processor. Further, the realization of a constituent element by hardware means that the function of the constituent element is realized by a hardware circuit.

  DESCRIPTION OF SYMBOLS 1 Servo control apparatus, 2 conveyance material, 3 mark, 4 mark sensor, 5 processing roll, 6 blades, 7 processing motor, 8 conveyance roll, 9 conveyance motor, 11 reference command generation means, 12, 16 gain means, 13 cam calculation Means, 14 conversion means, 15 drive control means, 17, 28, 29, 36 subtraction means, 18 cam computing means, 19 conversion means, 20 drive control means, 21 cam correction means, 21a cam correction means, 22 mark length error calculation Means 23 correction value calculating means 23a correction value calculating means 24 holding means 25 cam input correcting means 26 cam data changing means 27 27 delay means 31 error storage means 32 32a switching means 33 33a Determination means, 34, 34a Gain means, 35 Addition means, 100 Processing device.

Claims (1)

A transport roll for transporting a long transport material in which marks as processing target positions are given at predetermined intervals, a processing roll having a tool for processing the transport material, and a transport path for the transport material A servo control device applied to a machine tool provided with a sensor for detecting the passage of the mark,
A transport roll controller that rotates the transport roll in synchronization with the spindle operation;
A processing roll control unit that rotates the processing roll based on the main shaft operation, and an operation function that defines a relationship between the main shaft operation and the operation of the processing roll;
With
The processing roll control unit
A first calculator that calculates an error in the interval between marks based on the detection signal of the sensor;
The circumferential speed of the transport roll and the circumferential speed of the processing roll are equal to each other in the interval in the first section including the moment of processing by the tool in one rotation of the processing roll. The operation function is changed so that the processing roll makes one rotation while being conveyed by the distance of the interval between the marks by accelerating / decelerating in a second section different from the first section according to an error. 1 correction unit;
Equipped with a,
The processing roll control unit
A determination unit that determines whether an error in the interval is larger than a threshold;
A second correction unit that corrects an input value to the motion function by an amount corresponding to the error in the interval;
Further comprising
When it is determined that the error in the interval is larger than the threshold, the first correction unit changes the operation function,
The second correction unit corrects the input value when it is determined that an error in the interval is smaller than the threshold value;
A servo control device characterized by that.

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