JP2022185691A - Conveyance control device, conveyance control method and conveyance control program - Google Patents

Abstract

To provide a conveyance control device capable of stabilizing conveyance operations.SOLUTION: A conveyance control device 1 includes: a tension detector 21 for detecting a tension of a conveyed object 3; a main correction amount generation part 13 for generating a correction amount to a conveyance speed of the conveyed object 3 on the basis of a difference e between the detected tension and a tension command generated by a tension command generation part 111; a correction amount storage part 14 for storing a correction amount generated by the main correction amount generation part 13 when the difference e is less than a prescribed value; a correction amount switching part 15 for switching between the correction amount generated by the main correction amount generation part 13 and the correction amount stored by the correction amount storage part 14 for outputting; and a speed correction part 182 for correcting a conveyance speed of the conveyed object 3 on the basis of a correction amount α output by the correction amount switching part 15.SELECTED DRAWING: Figure 1

Description

The present invention relates to conveying technology.

2. Description of the Related Art As a conveying device for conveying a linear conveyed object such as a string or wire or a planar conveyed object such as paper or cloth, there is known a conveying device that detects the tension of the conveyed object. For example, Patent Literature 1 discloses a technique of generating an operation amount for a motor based on a difference between a detected wire tension value and a reference value, and maintaining the wire tension at the reference value.

Japanese Patent Application Laid-Open No. 2003-176080

In Patent Document 1, while the tension of the wire is maintained near the reference value, the operation amount of the motor always fluctuates according to minute fluctuations in the tension of the wire. Depending on the conveying conditions, minute fluctuations in the amount of operation of the motor may cause deformation of the conveyed object, which may reduce the yield of the conveying apparatus.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to provide a transport control device capable of stabilizing the transport operation.

In order to solve the above problems, a transport control device according to one aspect of the present invention includes a tension detector that detects the tension of a transported object, and a transport speed of the transported object based on the difference between the detected tension and the tension command. a correction amount generation unit that generates a correction amount for the difference, a correction amount storage unit that stores the correction amount generated by the correction amount generation unit when the difference is less than a predetermined value, a correction amount generated by the correction amount generation unit, and a correction amount storage a correction amount switching unit capable of switching and outputting the correction amount stored by the unit;

According to this aspect, the correction amount storage unit stores the correction amount generated by the correction amount generation unit when the difference between the detected tension and the tension command is less than the predetermined value, and the speed correction unit changes the conveying speed of the conveyed object. By using it for correction, the conveying speed of the conveyed object can be stabilized by a constant correction amount even when the tension varies minutely.

Another aspect of the present invention is a transport control method. This method includes a tension detection step of detecting the tension of the object to be conveyed, a correction amount generation step of generating a correction amount for the conveying speed of the object to be conveyed based on the difference between the detected tension and the tension command, and A correction amount storage step for storing the correction amount generated in the correction amount generation step when the value is less than the value, and a correction amount switching step for switching between the correction amount generated in the correction amount generation step and the correction amount stored in the correction amount storage step for output. and a speed correction step of correcting the transport speed of the transported object based on the correction amount output in the correction amount switching step.

Any combination of the above constituent elements, and any conversion of expressions of the present invention into methods, devices, systems, recording media, computer programs, etc. are also effective as embodiments of the present invention.

ADVANTAGE OF THE INVENTION According to this invention, the conveyance control apparatus which can stabilize a conveyance operation can be provided.

1 shows a first configuration example of a transport control device. 4 is a flow chart showing an example of processing of the transport control device; 3 shows a second configuration example of the transport control device.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In the description and drawings, the same or equivalent components, members, and processes are denoted by the same reference numerals, and overlapping descriptions are omitted as appropriate. The scales and shapes of the illustrated parts are set for convenience in order to facilitate explanation, and should not be construed as limiting unless otherwise specified. The embodiments are illustrative and do not limit the scope of the invention in any way. Not all features or combinations thereof described in the embodiments are essential to the invention.

FIG. 1 shows a first configuration example of a transport control device 1 according to an embodiment of the present invention. The transport control device 1 is a device that controls the transport operation of the transport device 2 that transports the object 3 to be transported. As will be described later, the transport control device 1 maintains the tension of the transported object 3 within a desired range by controlling the relative transport speeds of different portions of the transported object 3 . The transported object 3 may be anything as long as it can generate tension along the transport direction during transport. and the like are exemplified. The transport device 2, which uses paper as the transported object 3, is provided in a printing machine such as a rotary press, for example, and is in charge of feeding or discharging paper in each printing unit of a roll paper or a web as an object to be printed and transported. According to this embodiment, the tension of each portion of the web can be maintained within a desired range, so that the yield of the conveying device 2 and the printing press can be increased.

The conveying device 2 includes a tension detector 21 as a tension detector for detecting the tension of the object to be conveyed 3, a first roller unit 22 as a first conveying unit provided upstream of the tension detector 21, and a tension detector. 21 and a second roller portion 23 as a second conveying portion. Here, the terms "previous stage" and "subsequent stage" are defined with respect to the transport direction of the transported object 3 in the transport device 2 . In the illustrated example, the conveying direction of the object to be conveyed 3 is from left to right, and "front stage" means the left side opposite to the conveying direction, and "back stage" means the right side that is the same as the conveying direction. . Therefore, the first roller portion 22 is provided on the left side (front stage) of the tension detector 21 and the second roller portion 23 is provided on the right side (back stage) of the tension detector 21 .

Various types and structures of the tension detector 21 are known, and any one can be used as long as it is suitable for the transport mode of the transport device 2 . In the illustrated tension detector 21, a guide roller deviating from the transport path of the object 3 is provided between a pair of rollers 211 and 212 provided along the transport path of the object 3 (horizontal line extending from left to right). 213 is provided. A tension applied to a guide roller 213 combined with the tension detector 21 (provided in the tension detector 21 ) is detected as an electric signal by a detector 214 that is in contact with the guide roller 213 and is composed of a piezoelectric element or the like.

The first roller portion 22 sandwiches the conveyed object 3 between a first driving roller 221 driven to rotate in the conveying direction (clockwise direction in FIG. 1) by a motor (not shown) and the first driving roller 221 . A first driven roller 222 that rotates in the conveying direction (counterclockwise direction in FIG. 1) in conjunction with the first driving roller 221 is provided. As will be described later, the first drive roller 221 and the first driven roller 222 rotate at a first transport speed based on a speed command generated by the speed command generator 181 to transport the transported object 3 . Therefore, the conveying speed of the conveyed object 3 in the first roller portion 22 is the first conveying speed v1.

The second roller portion 23 sandwiches the conveyed object 3 between a second driving roller 231 driven to rotate in the conveying direction (clockwise direction in FIG. 1) by a motor (not shown) and the second driving roller 231 . A second driven roller 232 that rotates in the conveying direction (counterclockwise direction in FIG. 1) in conjunction with the second driving roller 231 is provided. As will be described later, the second driving roller 231 and the second driven roller 232 rotate at a second conveying speed obtained by adding a correction amount to the speed command generated by the speed command generating unit 181 to convey the conveyed object 3. . Therefore, the conveying speed of the conveyed object 3 in the second roller portion 23 is the second conveying speed v2.

When the correction amount is zero, the second conveying speed v2 is equal to the first conveying speed v1. At this time, the conveying speed of the conveyed object 3 is constant from the first roller portion 22 to the second roller portion 23, and the tension of the conveyed object 3 in the conveying device 2 does not change. When the correction amount is positive, the second conveying speed v2 is greater than the first conveying speed v1. At this time, since the transferred object 3 is pulled by the relative speed v2-v1, the tension of the transferred object 3 in the transfer device 2 increases. When the correction amount is negative, the second conveying speed v2 is smaller than the first conveying speed v1. At this time, since the transferred object 3 is loosened by the relative speed v1-v2, the tension of the transferred object 3 in the transfer device 2 is reduced. In this manner, the transport control device 1 can control the tension of the transported object 3 based on the value of the correction amount.

The conveying control device 1 includes a tension command generation unit 111, a difference calculation unit 112, a difference comparison unit 12, a main correction amount generation unit 13, a correction amount storage unit 14, a correction amount switching unit 15, and a speed correction amount. It includes a calculation unit 16 , a secondary correction amount generation unit 17 , a speed command generation unit 181 and a speed correction unit 182 . These functional units are realized through the cooperation of hardware resources such as the computer's central processing unit, memory, input device, output device, peripheral devices connected to the computer, and software executed using them. . Regardless of the type of computer or installation location, each of the above functional units may be realized by hardware resources of a single computer, or may be realized by combining hardware resources distributed among multiple computers. .

The tension command generation unit 111 generates a tension command for the transported object 3 transported by the transport device 2 . The transport control device 1 changes the second transport speed v2 with respect to the first transport speed v1 to maintain the tension of the transported object 3 within a desired range near the tension command. The difference calculator 112 is a subtractor that calculates the difference e between the tension of the transferred object 3 detected by the tension detector 21 and the tension command generated by the tension command generator 111 . The difference comparison unit 12 compares the absolute value of the difference e calculated by the difference calculation unit 112 (hereinafter simply referred to as the difference e) with a predetermined threshold value _e0 . As will be described later, when the absolute value of the difference e is equal to or greater than the threshold value _e0 and when the absolute value of the difference e is less than the threshold value _e0 , the processing of each section of the transport control device 1 is switched.

The main correction amount generator 13 generates a correction amount for the transport speed of the transported object 3 based on the difference e calculated by the difference calculator 112 . Specifically, the proportional calculation unit 131 calculates the proportional correction amount by a proportional calculation that multiplies the difference e by a predetermined proportional gain, and the integral calculation that multiplies the difference e by a predetermined integral gain and integrates the The main correction amount generation unit 13 is provided with an integral calculation unit 132 that calculates the integral correction amount. That is, the main correction amount generator 13 is a PI controller including a proportional calculator 131 as a P control (proportional control) element and an integral calculator 132 as an I control (integral control) element. A differential operation unit as a D control (differential control) element may be added here to configure the main correction amount generation unit 13 as a PID control unit. The D control element is not provided in this embodiment since it may be over-amplified. Note that the proportional gain of the proportional calculation section 131 and the integral gain of the integral calculation section 132 may be the same value or different values.

The correction amount storage unit 14 stores the correction amount generated by the main correction amount generation unit 13 according to the instruction from the difference comparison unit 12 when the difference e calculated by the difference calculation unit 112 is less than the threshold value _e0 . Specifically, a proportional correction amount storage unit 141 that stores the proportional correction amount calculated by the proportional calculation unit 131 and an integral correction amount storage unit 142 that stores the integral correction amount calculated by the integral calculation unit 132 perform correction. It is provided in the quantity storage unit 14 . The timing at which the proportional correction amount storage unit 141 stores the proportional correction amount and the timing at which the integral correction amount storage unit 142 stores the integral correction amount may be the same or different. For example, the proportional correction amount storage unit 141 stores the proportional correction amount at the timing when the difference e calculated by the difference calculation unit 112 falls below a _first value e1 that is equal to or smaller than the threshold value _e0 , and the difference calculation unit 112 calculates the proportional correction amount. The integrated correction amount storage unit 142 may store the integrated correction amount at the timing when the difference e thus obtained falls below a _second value e2 which is equal to or smaller than the threshold value _e0 .

The correction amount switching unit 15 can switch between the correction amount generated by the main correction amount generation unit 13 and the correction amount stored by the correction amount storage unit 14 and output the same. Specifically, a proportional correction amount switching unit 151 capable of switching between the proportional correction amount generated by the proportional calculation unit 131 and the proportional correction amount stored in the proportional correction amount storage unit 141 and outputting the integral correction amount generated by the integral calculation unit 132 The correction amount switching unit 15 is provided with an integral correction amount switching unit 152 capable of switching between the correction amount and the integral correction amount stored in the integral correction amount storage unit 142 and outputting the same. When the difference e calculated by the difference calculation unit 112 is equal to or greater than the threshold value _e0 , the correction amount switching units 151 and 152 generate correction amounts generated by the calculation units 131 and 132 in response to instructions from the difference comparison unit 12. and outputs the correction amounts stored in the correction amount storage units 141 and 142 according to the instruction from the difference comparison unit 12 when the difference e calculated by the difference calculation unit 112 is less than the threshold value _e0 .

The timing of switching the proportional correction amount switching unit 151 from the output of the proportional calculation unit 131 to the output of the proportional correction amount storage unit 141 and the timing of switching the integral correction amount switching unit 152 from the output of the integral calculation unit 132 to the The timing of switching to output may be the same or different. For example, as described above with respect to the correction amount storage unit 14, after the difference e falls below the _first value e1 which is equal to or less than the threshold value _e0 and the proportional correction amount storage unit 141 stores the proportional correction amount, the proportional correction amount switching unit 151 switches from the output of the proportional calculation unit 131 to the output of the proportional correction amount storage unit 141, the difference e falls below the _second value e2 which is equal to or less than the threshold value _e0 , and the integral correction amount storage unit 142 stores the integral correction amount. Later, the integral correction amount switching section 152 may switch the output of the integral calculation section 132 to the output of the integral correction amount storage section 142 .

After the proportional correction amount switching unit 151 switches the output of the proportional calculation unit 131 to the output of the proportional correction amount storage unit 141, the output of the proportional calculation unit 131 is maintained while the difference e is less than the threshold value _e0 or the _first value e1. is not used to control the transport speed of the transported object 3, the generation of the proportional correction amount by the proportional calculation unit 131 is stopped in accordance with the instruction from the difference comparison unit 12 to reduce power consumption, and the transport control device Calculation resources of one CPU (Central Processing Unit) can be released from the proportional calculation unit 131 and assigned to other functional units. Similarly, after the integral correction amount switching unit 152 switches from the output of the integral calculation unit 132 to the output of the integral correction amount storage unit 142, while the difference e is less than the threshold value _e0 or the _second value e2, the integral calculation unit Since the output of 132 is not used for controlling the conveying speed of the object to be conveyed 3, the generation of the integral correction amount by the integral calculating unit 132 is stopped in accordance with the instruction from the difference comparing unit 12, thereby reducing power consumption. The calculation resources of the CPU of the transport control device 1 can be released from the integration calculation section 132 and assigned to other functional sections.

The speed correction amount calculation unit 16 is an adder that adds the proportional correction amount output by the proportional correction amount switching unit 151 and the integral correction amount output by the integral correction amount switching unit 152 , and calculates the speed relative to the transport speed of the object 3 to be transported. A correction amount α is calculated. The secondary correction amount generated by the secondary correction amount generation section 17 is also input to the speed correction amount calculation section 16 . When the difference e calculated by the difference calculation unit 112 is less than the threshold value e of ₀ , the sub correction amount generation unit 17 as a second correction amount generation unit performs the correction based on the difference e according to the instruction from the difference comparison unit 12. A secondary correction amount is generated as a second correction amount for the conveying speed of the article to be conveyed 3 . The secondary correction amount generation unit 17 is provided with a proportional calculation unit 171 that calculates the secondary correction amount by proportional calculation in which the difference e is multiplied by a predetermined proportional gain. There is no integral calculation section for performing an integral calculation for .

The main role of the secondary correction amount generation unit 17 is to change the tension of the transferred object 3 after at least one of the correction amount switching units 151 and 152 switches the correction amount storage units 141 and 142 to the constant correction amount. to suppress low-frequency fluctuations that can occur in If the sub-correction amount generation unit 17 is provided with an integral calculation unit, the sub-correction amount may fluctuate greatly due to accumulation of tension fluctuations by the integral calculation, and the conveying operation of the conveying device 2 may become unstable. , the sub-correction amount generator 17 is provided with only the proportional calculator 171 .

As described above, the speed correction amount calculation unit 16, which is an adder, receives the proportional correction amount from the proportional correction amount switching unit 151, the integral correction amount from the integral correction amount switching unit 152, and the auxiliary correction amount from the auxiliary correction amount generation unit 17. Three data of correction amount (proportional correction amount) are input. Specifically, the data added by the speed correction amount calculator 16 changes as follows according to the difference comparison result in the difference comparator 12 . When the difference e calculated by the difference calculation unit 112 is equal to or greater than the threshold e ₀ , the proportional correction amount from the proportional calculation unit 131 output by the proportional correction amount switching unit 151 and the integral calculation unit output by the integral correction amount switching unit 152 The two data of the integral correction amount from 132 are added by the speed correction amount calculator 16 . At this time, since the secondary correction amount generator 17 is not operating, the secondary correction amount is not added by the speed correction amount calculator 16 . When the difference e calculated by the difference calculation unit 112 is less than the threshold value _e0 , the proportional correction amount from the proportional correction amount storage unit 141 output by the proportional correction amount switching unit 151 and the integral correction amount output by the integral correction amount switching unit 152 The speed correction amount calculation unit 16 adds three data, the integral correction amount from the correction amount storage unit 142 and the sub-correction amount from the sub-correction amount generation unit 17 .

The speed command generator 181 generates a command for the transport speed of the object 3 transported by the transport device 2 . As described above, the speed command generated by the speed command generation unit 181 corresponds to the first conveying speed v1 of the conveyed object 3 in the first roller unit 22 in the previous stage. The speed correction unit 182 is an adder that adds the speed correction amount α calculated by the speed correction amount calculation unit 16 to the speed command generated by the speed command generation unit 181. 3, the second conveying speed v2 is calculated. Thus, the speed correction amount α calculated by the speed correction amount calculation unit 16 designates the difference between the second conveying speed v2 and the first conveying speed v1 or the relative speed v2−v1 (=α). In other words, the speed correction unit 182 corrects the second conveying speed v2 of the transferred object 3 by the speed correction amount α calculated by the speed correction amount calculation unit 16 .

As described above regarding the speed correction amount calculation unit 16, when the difference e calculated by the difference calculation unit 112 is equal to or greater than the threshold value _e0 , the speed correction amount α is the proportional correction amount from the proportional calculation unit 131 and the integral calculation unit 132. is the sum of two data of the integral correction amount of . Further, when the difference e calculated by the difference calculation unit 112 is less than the threshold value _e0 , the speed correction amount α is the proportional correction amount stored in the proportional correction amount storage unit 141 and the integral correction amount stored in the integral correction amount storage unit 142. It is the sum of three data: the amount and the sub-correction amount generated by the sub-correction amount generation unit 17 . According to the present embodiment, when the tension difference e of the object to be transferred 3 is less than the threshold value _e0 , the second conveying speed v2 of the object to be transferred 3 is corrected by the constant correction amount stored in the correction amount storage unit 14. Therefore, it is possible to prevent minute fluctuations in the conveying speed of the conveyed object 3 caused by minute fluctuations in the tension of the conveyed object 3 . If the present embodiment is applied to a printing machine such as a rotary press, the difference e from the tension command of the tension of the roll paper as the printed material and the conveyed material 3 is maintained within a desired range, that is, less than the threshold value _e0 . Since the conveying operation of 2 can be stabilized, the yield of the conveying device 2 and the printing press can be increased.

FIG. 2 is a flow chart showing a processing example of the transport control device 1. As shown in FIG. In the description of the flowchart, "S" represents a step. In S1, the main correction amount generator 13 operates, and the proportional calculator 131 and the integral calculator 132 start generating the correction amount based on the tension difference e of the transferred object 3 calculated by the difference calculator 112 . In S2, the difference comparison unit 12 compares the absolute value of the tension difference e with the threshold value _e0 . In S2, when the tension difference e is equal to or greater than the threshold _e0 , the process proceeds to S3, and the proportional correction amount switching section 151 and the integral correction amount switching section 152 in the correction amount switching section 15 generate Proportional correction amount and integral correction amount are output respectively. In S4, the speed correction amount calculator 16 adds the proportional correction amount and the integral correction amount switched in S3 to calculate the speed correction amount α. 2 Correct the conveying speed v2. After S4, the process returns to S2.

If the tension difference e is less than the threshold value e ₀ in S2, the process proceeds to S5, and the proportional correction amount storage unit 141 and the integral correction amount storage unit 142 in the correction amount storage unit 14 are generated by the proportional calculation unit 131 and the integral calculation unit 132 A proportional correction amount and an integral correction amount are respectively stored. In S6, the proportional correction amount switching unit 151 and the integral correction amount switching unit 152 in the correction amount switching unit 15 change the proportional correction amount and the integral correction amount stored in the proportional correction amount storage unit 141 and the integral correction amount storage unit 142 in S5. Output each. In S7, the proportional calculation unit 131 and the integral calculation unit 132 in the main correction amount generation unit 13 stop generating correction amounts. In S<b>8 , the sub-correction amount generation unit 17 operates, and the proportional calculation unit 171 starts generating the sub-correction amount based on the tension difference e of the transferred object 3 calculated by the difference calculation unit 112 . In S9, the speed correction amount calculator 16 calculates the speed correction amount α by adding the proportional correction amount and integral correction amount switched in S6 to the sub-correction amount started to be generated in S8, and the speed correction unit 182 The second conveying speed v2 of the conveyed object 3 is corrected by the speed correction amount α.

In S10, the difference comparison unit 12 compares the absolute value of the tension difference e with the threshold value _e0 . If the tension difference e is less than the threshold _e0 in S10, the process returns to S9, the correction amount stored in the correction amount storage unit 14 (S5) is output by the correction amount switching unit 15 (S6), and the main correction amount generation unit 13 is stopped (S7), and the correction of the conveying speed of the conveyed object 3 is continued in a state where the sub-correction amount generating unit 17 is activated (S8). During this time, not only can the desired tension state in which the difference e is less than the threshold value _e0 be maintained, but also minute fluctuations in the tension of the conveyed object 3 can be prevented by using the constant correction amount stored in the correction amount storage unit 14. It is possible to prevent minute fluctuations in the correction amount and thus in the conveying speed.

When the tension difference e becomes equal to or greater than the threshold value _e0 in S10, the process proceeds to S11, in which the main correction amount generation unit 13 operates to restart generation of the correction amount. In S12, the proportional calculation unit 171 in the secondary correction amount generation unit 17 stops generating the correction amount, and the process returns to S3.

FIG. 3 shows a second configuration example of the transport control device 1 according to the embodiment of the present invention. The same reference numerals are given to the same components as in the first configuration example of FIG. The conveying device 2 includes a dancer 24 as a tension detector that detects the tension of the object 3 to be conveyed. The dancer 24 is provided with a dancer roll 243 deviated from the transport path of the object 3 between a pair of rollers 241 and 242 provided along the transport path of the object 3 (horizontal line extending from left to right). .

The dancer roll 243 is provided movably between an upper end 243A and a lower end 243B in a direction perpendicular to the conveying path of the object 3 (vertical direction in FIG. 3). is urged or pressurized in the direction (downward in FIG. 3) away from the transport path of the transported object 3 by . The biased or pressurized dancer roll 243 applies tension to the transferred object 3 by pulling the transferred object 3 in a direction away from the transfer path. In other words, the dancer roll 243 stops at a position where the downward force received from the air cylinder 244 and the upward tension received from the transferred object 3 are balanced. Since the force that the dancer roll 243 receives from the air cylinder 244 is substantially constant, the position of the dancer roll 243 represents the tension of the object 3 to be conveyed.

The position of the dancer roll 243 is detected as an electric signal by the position sensor 245 and supplied to the difference calculator 112 . In addition, the position command for the dancer rolls 243 generated by the position command generation unit 113 is input to the difference calculation unit 112 . As described above, the position of the dancer rolls 243 corresponds to the tension of the transferred object 3 , so the position command of the dancer rolls 243 generated by the position command generation unit 113 corresponds to the tension command of the transferred object 3 . Therefore, the difference calculation unit 112 calculates the difference e between the detected tension of the transferred object 3 and the tension command, as in the first configuration example of FIG. Other components in FIG. 3 are the same as those in FIG. 1, so description thereof will be omitted.

The present invention has been described above based on the embodiments. It should be understood by those skilled in the art that the embodiments are examples, and that various modifications can be made to combinations of each component and each treatment process, and such modifications are also within the scope of the present invention.

In the embodiment, the correction amount storage unit 14 is provided with the proportional correction amount storage unit 141 that stores the proportional correction amount and the integral correction amount storage unit 142 that stores the integral correction amount. may be provided only. When only the integral correction amount storage unit 142 is provided, the integral correction amount switching unit 152 switches to the stored integral correction amount, thereby avoiding the accumulation of minute variations in tension when the tension difference e is less than the threshold value _e0 . Therefore, the transport operation of the transport device 2 can be stabilized. If the proportional correction amount storage unit ₁₄₁ is not provided, the proportional correction amount generated by the proportional calculation unit 131 is always used. The proportional calculation unit 171 or the sub-correction amount generation unit 17 provided for generation may not be provided. In this case, the proportional gain of the proportional calculation unit 131 may be changed when the tension difference e is equal to or greater than the threshold value _e0 and when the tension difference e is less than the threshold value _e0 .

Note that the functional configuration of each device described in the embodiments can be realized by hardware resources, software resources, or cooperation between hardware resources and software resources. Processors, ROMs, RAMs, and other LSIs can be used as hardware resources. Programs such as operating systems and applications can be used as software resources.

Reference Signs List 1 transport control device 2 transport device 3 transported object 12 difference comparison unit 13 main correction amount generation unit 14 correction amount storage unit 15 correction amount switching unit 16 speed correction amount calculation unit 17 sub correction amount generation Part 21 Tension detector 22 First roller part 23 Second roller part 24 Dancer 111 Tension command generator 112 Difference calculator 113 Position command generator 131 Proportional calculator 132 Integral calculator 141 Proportional correction amount storage unit 142 Integral correction amount storage unit 151 Proportional correction amount switching unit 152 Integral correction amount switching unit 171 Proportional calculation unit 181 Speed command generation unit 182 Speed correction unit 243 Dancer roll.

Claims (8)

a tension detector that detects the tension of the object to be transported;
a correction amount generation unit that generates a correction amount for the conveying speed of the conveyed object based on the difference between the detected tension and the tension command;
a correction amount storage unit that stores the correction amount generated by the correction amount generation unit when the difference is less than a predetermined value;
a correction amount switching unit capable of switching and outputting the correction amount generated by the correction amount generation unit and the correction amount stored by the correction amount storage unit;
a speed correction unit that corrects the transport speed of the transported object based on the correction amount output by the correction amount switching unit;
A transport control device comprising: The correction amount switching unit outputs the correction amount generated by the correction amount generation unit when the difference is equal to or greater than the predetermined value, and outputs the correction amount stored in the correction amount storage unit when the difference is less than the predetermined value. 2. The transport control device according to claim 1, which outputs. The correction amount storage unit stores the correction amount generated by the correction amount generation unit when the difference becomes less than the predetermined value;
After the correction amount storage unit stores the correction amount, the correction amount generation unit stops generating the correction amount while the difference is less than the predetermined value.
The transport control device according to claim 2. The correction amount generation unit includes a proportional calculation unit that performs proportional calculation on the difference and an integral calculation unit that performs integral calculation on the difference,
a second correction amount generation unit for generating a second correction amount for the conveying speed of the object to be conveyed based on the difference when the difference is less than the predetermined value, the proportional calculation unit performing proportional calculation for the difference; and further comprising a second correction amount generation unit that does not include an integration operation unit that performs an integration operation on the difference,
When the difference is less than the predetermined value, the speed correction unit adjusts the conveying speed of the object based on the correction amount stored in the correction amount storage unit output by the correction amount switching unit and the second correction amount. to correct the
The transport control device according to claim 2 or 3. The tension detection unit detects a position of a dancer roll that applies tension to the transported object,
The correction amount generating section calculates a correction amount for the conveying speed of the article to be conveyed based on the difference between the position of the dancer roll detected by the tension detecting section and the position command of the dancer roll corresponding to the tension command. generate,
The transport control device according to any one of claims 1 to 4. The object to be conveyed is conveyed by a first conveying section provided before the tension detecting section and a second conveying section provided after the tension detecting section,
The speed correcting unit corrects the conveying speed of the second conveying unit with respect to the first conveying unit based on the correction amount output by the correction amount switching unit.
The transport control device according to any one of claims 1 to 5. a tension detection step of detecting the tension of the object to be conveyed;
a correction amount generating step of generating a correction amount for the transport speed of the transported object based on the difference between the detected tension and the tension command;
a correction amount storage step for storing the correction amount generated in the correction amount generation step when the difference is less than a predetermined value;
a correction amount switching step for switching and outputting the correction amount generated in the correction amount generation step and the correction amount stored in the correction amount storage step;
a speed correction step of correcting the transport speed of the transported object based on the correction amount output in the correction amount switching step;
A transportation control method comprising: a tension detection step of detecting the tension of the object to be conveyed;
a correction amount generating step of generating a correction amount for the transport speed of the transported object based on the difference between the detected tension and the tension command;
a correction amount storage step for storing the correction amount generated in the correction amount generation step when the difference is less than a predetermined value;
a correction amount switching step for switching and outputting the correction amount generated in the correction amount generation step and the correction amount stored in the correction amount storage step;
a speed correction step of correcting the transport speed of the transported object based on the correction amount output in the correction amount switching step;
A transport control program that causes a computer to execute

Images