JP5942906B2 - Speed control device, image processing device, speed control program - Google Patents

Description

  The present invention relates to a speed control device, an image processing device, and a speed control program.

  In Patent Document 1, when a plurality of rolls are driven by a plurality of electric motors corresponding to the respective rolls and a sheet-like material continuous in the length direction is conveyed, a ratio of speed setting values of the electric motors is determined in advance. The tension of the sheet material between the rolls is held at a predetermined value.

  Moreover, in patent document 2, when conveying a web using the 1st-3rd AC servomotor, a 2nd AC servomotor takes charge of web conveyance speed, and it is a 1st and 3rd AC servomotor. A technique for maintaining tension by controlling torque is described.

  Patent Document 3 describes a technique for automatically adjusting the draw rate. A dancer roller is used for tension detection, and when the tension exceeds an allowable value, the draw rate is automatically adjusted.

JP 03-2111156 A Japanese Patent Laid-Open No. 08-085659 JP 2001-278518 A

  The present invention relates to a speed control apparatus and an image processing apparatus that can convey a conveyance medium that is sandwiched between a plurality of drive rollers of unlimited number and receives a conveyance force while applying an optimum tension between the rollers. The purpose is to obtain a speed control program.

According to the first aspect of the present invention, a plurality of rollers that apply a conveyance force to the sheet and form a conveyance path, a plurality of driving units that independently drive the plurality of rollers, and the plurality of rollers are appropriately selected. The difference between the tension of the sheet generated between the upstream roller in the sheet conveying direction and the tension of the sheet generated between the downstream roller in the sheet conveying direction with the specified roller as a reference. Accordingly, the peripheral speed of the specific roller is maintained and the peripheral speed of the upstream roller or the downstream roller is set so that the torque of the drive unit that drives the specific roller is a predetermined target value. and control means for controlling said control means, and selection means for selecting a particular roller from a plurality of rollers, based on the particular roller selected by the selecting means, generated between the upstream side roller Measuring means for measuring the torque of a drive unit that varies according to the difference between the tension of the sheet and the tension of the sheet generated between the downstream roller and that drives the specific roller; Calculation means for calculating an increase / decrease amount for setting the torque measured by the means to a predetermined target value, and based on the increase / decrease amount of the torque calculated by the calculation means, the upstream roller or the downstream roller, Setting means for setting a draw rate that is a ratio of the peripheral speed of the specific roller; and holding the peripheral speed of the specific roller so that the draw rate set by the setting means is the upstream side And an adjusting means for adjusting the peripheral speed of the roller or the downstream roller .

According to a second aspect of the present invention, in the first aspect of the invention, after the control of the peripheral speed of the driving unit is completed in the control unit, the specific roller is placed on the conveyance path in the upstream direction or the downstream direction. The arrangement order is selected in accordance with the arrangement order, and the control by the control means is continued for each selection.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the sheet generated between the upstream roller and the specific roller at the start of control by the control means is used. The difference in tension between the tension and the tension of the sheet generated between the downstream rollers is set to zero.

According to a fourth aspect of the present invention, the speed control according to any one of the first to third aspects is provided, and an image reading apparatus that reads at least image information or an image as a processing unit between the plurality of rollers. An image processing apparatus includes any one of image forming apparatuses that form an image on a recording sheet based on information.

According to the fifth aspect of the present invention, a plurality of rollers that impart a conveyance force to the sheet and form a conveyance path are driven and controlled by an independent drive unit, and a specific roller is selected from the plurality of rollers. The sheet is changed according to the difference between the tension of the sheet generated with the upstream roller and the tension of the sheet generated with the downstream roller, with the selected specific roller as a reference, and Measure the torque of the drive unit that drives the specific roller, calculate an increase / decrease amount for making the measured torque a predetermined target value, and based on the calculated increase / decrease amount of the torque, the upstream roller Alternatively, the upstream roller is set so that a draw rate, which is a ratio of a peripheral speed between the downstream roller and the specific roller, is set, and the peripheral speed of the specific roller is held to obtain a set draw rate. Is a speed control program to be executed that, adjusting the peripheral speed of the downstream roller.

  According to the first aspect of the present invention, it is possible to convey a conveyance medium that is sandwiched between a plurality of drive rollers that are not limited in number and receives a conveyance force by applying an optimum tension between the rollers. .

The motor serving as a torque control target, can be carried out at a peripheral speed adjustment of the adjacent motor.

According to the second aspect of the present invention, it is possible to convey by applying an optimum tension between a plurality of rollers by repeating simple control.

According to the invention described in claim 3 , the initial control can be simplified.

According to the fourth aspect of the present invention, it is possible to convey a conveyance medium sandwiched between a plurality of drive rollers of unlimited number and receiving a conveyance force by applying an optimum tension between the rollers. .

According to the fifth aspect of the present invention, it is possible to convey a conveyance medium sandwiched between a plurality of drive rollers of unlimited number and receiving a conveyance force by applying an optimum tension between the rollers. .

1 is a schematic diagram of an image processing apparatus according to the present embodiment. It is a schematic diagram which shows the information memorize | stored in the memory | storage part of a control part. It is the schematic which shows the basic principle of the torque control of this Embodiment. It is a flowchart which shows the tension control routine which concerns on this Embodiment. 5 is a control flowchart showing details of a draw rate teaching mode in the tension control of FIG. 4.

(Schematic configuration of the image forming apparatus 10)
As shown in FIG. 1, an image processing apparatus 10 according to the present embodiment includes a paper feeding device 16 that winds and stores a long paper 12 (hereinafter referred to as “roll paper 12”) around a reel 14. Yes. The reel 14 is provided with a shaft brake (not shown) and is braked so that the tension when the uppermost roll paper 12 is pulled out is always constant.

  As shown in FIG. 1, after the roll paper 12 is pulled out from the paper supply device 16, it is sandwiched between a plurality of pairs of rollers 18 and predetermined conveyance paths (in this embodiment, straight conveyance paths). It is designed to be transported along. In the present embodiment, N roller pairs 18 are arranged. When collectively referred to, the roller pair 18 is used, and when distinguishing each, (1), (2). N-1) and (N) are attached.

  One of the roller pairs 18 is independently connected to the drive shaft of the motor 20, which is a drive source, via a transmission 40. For this reason, it is possible to give independent conveyance speeds to the roll paper 12 from each roller pair 18. An AC servomotor is applied to the motor 20, and the rotation speed is controlled according to the current value. The motor is not limited to an AC servo motor as long as the motor can control the rotational speed.

  In the present embodiment, N motors 20 are arranged for driving the roller pair 18, and are collectively referred to as motors 20, and when distinguished from each other, (1), (2) ... (N-1) and (N) are attached.

  The motor 20 is collectively managed by the control of the speed control unit 36, and the rotation speed (circumferential speed) is controlled.

  Note that torque is generated even when the motor 20 rotates with no load, and this is referred to as loss torque, and loss torque unique to each motor 20 can be recognized and stored in advance (described later). ).

  A plurality of types of processing units 22 (1), 22 (2),... 22 (n) are provided at appropriate positions between the roller pair 18. The processing units 22 (1), 22 (2)... 22 (n) are processed by the control of the processing control units 32 (1), 32 (2). It is supposed to be executed.

  The processing types of the processing units 22 (1), 22 (2)... 22 (n) are pre-processing, image forming processing (printing), coating processing, post-processing, etc. The processing units 22 (1), 22 (2)... 22 (n) that execute these processes can be selectively installed.

  In FIG. 1, a plurality of types of processing units 22 (1), 22 (2)... 22 (n) are illustrated, but may be a single type or a plurality of the same processing types may be installed. Also good. Furthermore, it may be installed not only on the front surface (upper surface in FIG. 1) of the roll paper 12 but also on the rear surface (lower surface in FIG. 1).

  The processing control units 32 (1), 32 (2)... 32 (n) in the main control unit 30 are collectively managed by the main controller 30M, such as synchronous control.

  The roll paper 12 that has been processed in the processing section 22 is stored in a storage device 24 provided on the downstream side of the last-stage roller pair 18 (N). The storage device 24 receives the roll paper 12 by winding it around a reel 26 in the same manner as the paper supply device 16. A motor 28 is connected to the reel 26 of the storage device 24, and a rotational driving force is applied to the reel 26 in the same manner as the roller pair 18. The motor 28 is managed under the control of the speed control unit 36.

  The housing device 24 is provided with a dancer roll portion 24D. The dancer roll unit 24D is wound with the roll paper 12 fed from the roller pair 18 (N) at the final stage, and includes tension between the roller pair 18 (N) and tension due to the winding force on the reel 26. Due to the difference, a part of the rollers of the dancer roll section 24D moves in the direction perpendicular to the axis, thereby having a function of canceling out (matching) the tension difference.

  Here, in the image processing apparatus 10 according to the present embodiment, as described above, the reel 14 of the paper feeding device 16 is provided with the shaft brake. The tension T0 of the roll paper 12 until it is sandwiched between the roller pair 18 (1) is always kept constant.

  That is, the peripheral speed of the uppermost layer when pulled out from the paper feeder 16 is the same as the peripheral speed of the first-stage roller pair 18 (1). The ratio between the upstream and downstream peripheral speeds (downstream peripheral speed / upstream peripheral speed) may be referred to as a draw rate. Here, the draw rate is “1” (100%).

  Here, N (N is a positive integer) roller pairs 18 are arranged in the conveyance path of the present embodiment, and these N roller pairs 18 are at a constant rotational speed (circumferential speed). If it rotates, the tension of the roll paper 12 between each pair of rollers 18 is theoretically held at the desired tension. The desired tension varies depending on the type of the roll paper 12, and is stored in a table in advance in the storage unit 34 of the control unit 30 (see FIG. 2).

  The technique for generating tension on the roll paper 12 can be executed by general speed control in which the peripheral speed of the roller pair 18 is increased toward the downstream side. Therefore, when the desired tension is determined, the speed control unit 36 of the control unit 30 executes the peripheral speed control of the roller pair 18 and the reel 24, and the basic tension control is executed. The speed control unit 36 is connected to the main controller 30M and is instructed with a conveyance speed and a tension according to the type of the roll paper 12.

  However, due to factors such as machine differences, friction coefficient between the roll paper 12 and the roller pair 18 and aging deterioration, theoretical values may not necessarily be obtained. This phenomenon may be accumulated as the number of roller pairs 18 increases (the N value increases).

  Therefore, in the present embodiment, roll paper between the paper feeder 16 that is known in advance (the draw rate is 100%) and the first-stage roller pair 18 (1) under the control of the speed control unit 36. Based on the tension T0 of 12, the peripheral speed control (torque control) of the motor 20 is executed according to the arrangement order as in the second-stage, third-stage,... Yes.

  That is, the torque control of the motor 20 to be controlled is sequentially executed by controlling the peripheral speed of the motor 20 of the next-stage roller pair 18, so that the circumference of the motor 20 up to the final-stage roller pair 18 (N) is increased. Set the speed. In this embodiment, since the reel 26 of the storage device 24 cancels out the tension difference by the dancer roller portion 24D, the motor 28 is not controlled here.

  Hereinafter, the roller pair 18 that rotates with the driving force of the motor 20 to be torque controlled is referred to as a “specific roller pair 18”.

  In the torque control of the motor 20, first, the upstream tension (corresponding to the tension Th in FIG. 3) and the downstream tension (FIG. 3) of the roll paper 12 sandwiched between the roller pair 18 following the specific roller pair 18. The draw ratio, which is the peripheral speed ratio between the specific roller pair 18 and the next-stage roller pair 18, is determined based on the difference from the tension Td (corresponding to the tension Td) (first control).

  Next, based on the determination of the draw rate, the peripheral speed of the motor 20 that is the drive source of the next-stage roller pair 18 is controlled (second control).

  The results of the first control and the second control are reflected in the torque control of the motor 20 that drives the specific roller pair 18.

  That is, increasing the peripheral speed of the motor 20 of the next roller pair 18 means increasing the draw rate, and the torque of the motor 20 of the specific roller pair 18 is reduced.

  On the other hand, reducing the peripheral speed of the motor 20 of the roller pair 18 in the next stage means lowering the draw rate, and the torque of the motor 20 of the specific roller pair 18 increases.

  In the present embodiment, when the torque of the motor 20 of the specific roller pair 18 is determined, the first control and the second control are executed by using the next roller pair 18 as the new specific roller pair 18. Yes. By repeating this up to the final stage (in this embodiment, the roller pair 18 (N)), the tension can be gradually adjusted from one of the conveyance paths regardless of the number of roller pairs 18.

  The torque control is derived from the following basic principle.

(Basic principle of torque control of this embodiment)
First, as a basic configuration, as shown in FIG. 3, the relationship between tensions on the upstream side and the downstream side in a state where the roll paper 12 is sandwiched between a single roller pair 18 is shown.

  As shown in FIG. 3, it is assumed that the roll paper 12 is sandwiched between a single roller pair 18, and the roll paper 12 is being conveyed at a constant conveyance speed vp.

  The rotation shaft 19 of the roller 18L located on the lower side of the roller pair 18 in FIG. 3 is connected to the drive shaft 20D of the motor 20 via the transmission 40. For this reason, the roller 18L rotates according to the gear ratio of the transmission 40 according to the driving force of the motor 20. The conveyance speed given to the roll paper 12 depends on the outer diameter Dr of the roller 18L.

  Here, when the roll paper 12 is being transported at a constant transport speed vp, when the circumferential speed vr of the roller pair 18 is faster than the transport speed vp of the roll paper 12 (vp <vr), the upstream tension Th becomes higher than the downstream tension Td. On the other hand, when the circumferential speed vr of the roller pair is slower than the transport speed vp of the roll paper 12, the downstream tension Td becomes higher than the upstream tension Th.

  That is, if the upstream tension Th matches the downstream tension Td, the peripheral speed vr of the roller pair 12 and the roll paper transport speed vp match.

Td = Th + {(Rg) / (Dr)} × {(tm) − (tl)} (1)
here,
Td: Tension applied to the roll paper 12 on the downstream side of the roller pair 18 Th: Tension applied to the roll paper 12 on the upstream side of the roller pair 18 Rg: Gear ratio Dr: Diameter of the roller pair 18 tm: During rotation of the motor 20 Torque (motor torque)
tl: Loss torque.

  In (1), the loss torque may be acquired by driving the motor 20 in a no-load state in advance as described above. Actual measurement is required to acquire this loss torque, but actual measurement is possible even when the apparatus is assembled or when periodic maintenance is used.

  Further, since the gear ratio Rg is determined by the configuration of the transmission 40 and the roller diameter Dr is determined by a physical structure, (gear ratio) / (roller diameter) is a known constant (default value). The predetermined values (loss torque, gear ratio, roller diameter) are stored in the storage unit 34 (see FIG. 2) and can be updated as appropriate.

  Thus, when the torque generated when the motor 20 is driven is known, the relationship between the tension Th applied to the upstream roll paper 12 of the roller pair 18 and the tension Td applied to the downstream roll paper 12 is recognized. It becomes possible.

  Here, the tension difference determined by the speed difference (draw rate) between the circumferential speed vr of the roller pair 18 and the roll paper transport speed vp depends on the rotational torque tm when the motor 20 is driven (the first control). .

  Accordingly, when it is desired to obtain a desired tension difference (target value), the increase / decrease amount of the rotational torque for obtaining the target value may be calculated to control the circumferential speed vr of the roller pair 18 (the second control). ).

  Hereinafter, the flow of the draw rate setting control during the conveyance of the roll paper 12 will be described according to the flowchart of FIG.

  FIG. 4 is a flowchart showing a tension control routine.

  First, in step 100, it is determined whether it is time to execute tension control. In the present embodiment, as an example of the execution time, an instruction from the user may be given when the image processing apparatus 10 is initially installed (9 including after moving installation, after a certain period of time has elapsed).

  If a negative determination is made in step 100, it is determined that it is not time to execute tension control, and this routine is terminated.

  If an affirmative determination is made in step 100, it is determined that it is time to execute tension control, and the process proceeds to step 102.

  In step 102, it is determined whether or not the stored default value correction time is reached. The default values include the loss torque of the motor 20, the diameter of the roller 18, and the gear ratio of the transmission 40. These may fluctuate over time, so they are not stored permanently and may be corrected as appropriate. preferable.

  If an affirmative determination is made in step 102, the routine proceeds to step 104, where each roller pair 18 is first driven to rotate without the paper 12, and then the routine proceeds to step 106, where the motor 20 generated at the time of rotational driving without paper is detected. Torque is measured and the process proceeds to step 108.

  In step 108, the measured torque is updated as loss torque (overwritten and stored in the storage unit 34).

  In the next step 110, the roller diameter and gear ratio are reset, and the routine proceeds to step 112. If the determination in step 102 is negative, it is determined that the correction of the default value is unnecessary, and the process proceeds to step 112.

  In step 112, the paper 12 is set, and the process proceeds to step 114 to execute the draw rate teaching mode control (see FIG. 5).

  FIG. 5 shows a detailed procedure of the draw rate teach mode control in step 112 of FIG.

  In step 150, the variable value i for specifying the roller pair 18 (i) is set to 0 as an initial setting, and then the process proceeds to step 152 to read the appropriate tension from the type of the roll paper 12. That is, the tension value corresponding to the type of the roll paper 12 is read from the table stored in the storage unit 34 of the control unit 30.

  In the next step 154, the preset values (loss torque, gear ratio, roller diameter) of each roller pair 18 stored in advance are read, and the process proceeds to step 156, where each motor 20 based on this specified value and appropriate tension is read. Calculate the motor torque.

  In the next step 158, the variable value i is incremented (i ← i + 1), and the process proceeds to step 160.

  In step 160, the motor torque of the motor 20 (i), which is the drive source of the i-th stage roller pair 18 (i), is measured, and then the process proceeds to step 162 where the difference between the measured motor torque and the appropriate torque is obtained. Based on this, the draw rate is calculated, and the process proceeds to step 164.

  In step 164, the peripheral speed of the motor 20 (i + 1) on the (i + 1) th stage surface is adjusted based on the draw rate.

  When adjustment is made to increase the peripheral speed of the motor 20 (i + 1) of the next-stage roller pair 18 (i + 1), the draw rate increases and the torque of the motor 20 of the roller pair 18 (i) decreases.

  On the other hand, when adjustment is made to slow down the peripheral speed of the motor 20 (i + 1) of the roller pair 18 (i + 1) at the next stage, the draw rate decreases and the torque of the motor 20 (i) of the roller pair 18 (i) increases. Become.

  In the next step 166, it is determined whether or not the variable value i has reached N, that is, whether or not the variable value indicating the last roller pair 18 has been reached. Is incremented, the above affirmation (steps 160, 162, 164) is repeated. If an affirmative determination is made in step 166, it is determined that all adjustments have been completed, and this routine ends.

  In the present embodiment, the first-stage roller pair 18 (1) and the second stage are based on the tension T0 between the reel 14 of the paper feeder 16 and the first-stage roller pair 18 (1). The tension between the second roller pair 18 (2) is converted into the torque of the first stage motor 20 (1), and the torque is adjusted by adjusting the peripheral speed of the second stage motor 20 (2). By sequentially executing the control up to the N-th roller pair 18 (N), it is possible to moderately maintain the tension between each roller pair 18 moderately without producing an accumulated error.

  In the present embodiment, the adjustment of the peripheral speed based on the draw rate of the motor 20 is performed from the supply device 16 side, but may be performed from the accommodation device 24 side.

  In addition, a plurality of rollers that apply a conveyance force to the sheet and form a conveyance path to the computer including the main controller 30M according to the present embodiment are driven and controlled by independent drive units, and the specific rollers are controlled by the plurality of rollers. And based on the selected specific roller, the sheet tension varies with the difference between the sheet tension generated with the upstream roller and the sheet tension generated with the downstream roller. And measuring a torque of a driving unit that drives the specific roller, calculating an increase / decrease amount for setting the measured torque to a predetermined target value, and based on the calculated increase / decrease amount of the torque, A draw rate, which is a ratio of the peripheral speed between the upstream roller or the downstream roller and the specific roller, is set, the peripheral speed of the specific roller is maintained, and the set draw As the speed control program for the adjusting the peripheral speed of the upstream roller or downstream roller, to execute it, may be stored in various recording media.

10 Image forming apparatus 12 Roll paper (paper)
DESCRIPTION OF SYMBOLS 14 Reel 16 Paper feeder 18 Roller pair 20 Motor 22 Processing part 24 Storage device 24D Dancer roll part 26 Reel 28 Motor 30 Control part 30M Main controller 32 Processing control part 34 Storage part 36 Speed control part 40 Transmission

Claims (5)

A plurality of rollers for applying a conveying force to the sheet and forming a conveying path;
A plurality of driving units for independently driving the plurality of rollers;
The sheet generated between the tension of the sheet generated with the upstream roller in the sheet conveying direction and the downstream roller in the sheet conveying direction with a specific roller appropriately selected from the plurality of rollers as a reference In order to set the torque of the drive unit that drives the specific roller to a predetermined target value, the peripheral speed of the specific roller is maintained and the upstream roller or Control means for controlling the peripheral speed of the downstream roller ,
The control means is
Selecting means for selecting a specific roller from a plurality of rollers;
Fluctuates according to the difference between the tension of the sheet generated between the upstream roller and the tension of the sheet generated between the downstream roller and the specific roller selected by the selection unit. And measuring means for measuring the torque of the driving unit for driving the specific roller,
A calculating means for calculating an increase / decrease amount for setting the torque measured by the measuring means to a predetermined target value;
Setting means for setting a draw rate, which is a ratio of the peripheral speeds of the upstream roller or the downstream roller and the specific roller, based on the increase / decrease amount of the torque calculated by the calculation means;
Adjusting means for holding the peripheral speed of the specific roller and adjusting the peripheral speed of the upstream roller or the downstream roller so as to achieve the draw rate set by the setting means;
A speed control device comprising: In the control means, after the control of the peripheral speed of the drive unit is completed, the specific roller is selected in the order of arrangement along the conveyance path in the upstream direction or the downstream direction, and the control by the control means is continued for each selection. The speed control device according to claim 1 . The difference between the tension of the sheet generated with the upstream roller and the tension of the sheet generated with the downstream roller with respect to the specific roller at the start of control by the control unit. The speed control device according to claim 1 or 2, wherein a difference in tension is zero . An image reading apparatus that reads at least image information or an image on a recording sheet based on the image information is provided as a processing unit between the plurality of rollers. An image processing apparatus including any one of image forming apparatuses to be formed. On the computer,
  A plurality of rollers that apply conveyance force to the sheet and form a conveyance path are driven and controlled by independent drive units,
  A specific roller is selected from the plurality of rollers,
  Fluctuating according to the difference between the tension of the sheet generated between the upstream roller and the tension of the sheet generated between the downstream roller with respect to the selected specific roller, and Measure the torque of the drive that drives the specific roller,
  Calculate the increase / decrease amount to make the measured torque a predetermined target value,
  Based on the calculated increase / decrease amount of the torque, a draw rate that is a ratio of the peripheral speeds of the upstream roller or the downstream roller and the specific roller is set,
  Holding the peripheral speed of the specific roller and adjusting the peripheral speed of the upstream roller or the downstream roller so as to achieve a set draw rate;
A speed control program to make things happen.

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