KR920000752B1 - Dryer control apparatus of papermaking machine - Google Patents

Abstract

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Description

Paper Maker Dryer

1 is a view showing the arrangement of the drying unit according to the first embodiment of the present invention.

2 is a view showing an arrangement of a drying unit according to a second embodiment of the present invention.

3 is a view showing an arrangement of a drying unit according to a third embodiment of the present invention.

4 is a view showing an arrangement of a drying unit according to a fourth embodiment of the present invention.

5 is a view showing an arrangement of a drying unit according to a fifth embodiment of the present invention.

6 is a view for explaining the ability to lower power.

The present invention relates to an improvement of a paper machine dryer, and more particularly to a drive system for driving rolls of the dryer. U.S. Patent 3,815,256 describes an example of a paper machine dryer, but this type has the disadvantage of having to have a large number of parts. In order to solve such a problem, US Patents 4,495,711 and 4,495,712 have been proposed, which suggests that the dryer drivers vary the rotational speed of each roll and the number of motors for directly driving a canvas roll or cylinder roll. Controllers for controlling the motors to synchronize with the controller.

According to the configuration as described in the two US patents, the rolls being driven are synchronized with each other and have the same rotational speed. Since the paper web is wet at the inlet of the dryer and dried at the outlet, it is desirable to change the paper feed rate even in a single dryer. However, it is difficult to realize such a speed change because the driven rolls are synchronously rotated with each other. In addition, the paper web is torn or wrinkled when the load on each motor in the dryer driver fluctuates for some reason.

It is therefore an object of the present invention to provide a paper maker dryer in which the rolls being driven can be controlled under a properly distributed load at a suitable speed.

In order to achieve the above object, a plurality of cylinder rolls 1A-1F, a plurality of canvas rolls 2A-3H, and acting between the cylinder rolls 1A-1F and the canvas rolls 2A-2H The conveying means for drying the paper web W to be dried while the paper web W composed of the canvases 3 is conveyed, and the cylinder rolls 1A-1F and the canvas rolls 2A-2H. A plurality of joints for conveying a predetermined path of the paper web W to be dried by being coupled to the interlocking rolls and for driving each of the at least one interlocking roll for drying the paper by the cylinder rolls 1A-1F and the canvases 3 respectively. Paper making machine consisting of a motor 4A-4H of the motor and a motor controller 14A-14H provided respectively to the motor 4A-4H to control the speed and load distribution of the motor 4A-4H, respectively. Provide wealth.

With the above arrangement, the drying unit of the present invention can individually control the motors for driving the rolls in a suitable mode to prevent the paper web to be dried from being torn or wrinkled.

The paper machine drying unit according to the first embodiment of the present invention will be described below with reference to FIG. 1 shows an arrangement of a drying unit according to the first embodiment of the present invention. This drying part is arranged behind the wire and press part of the paper maker, and a calender part and a reel part are arranged behind the drying part.

The pulp liquid is led to the dewatering wire part and compressed in the press part to become wet paper. This wet paper is dried in the drying section shown in FIG. 1, finished in the calendar section, and wound on the reel section. In FIG. 1, the three cylinder rolls 1A-1C and the four canvas rolls 2A-2D are arranged in a staggered fashion in cooperation in the lower stage. Similarly, the upper canvas 3 to guide and dry the wet paper around the three cylinder rolls runs between the upper rolls and the lower canvas 3 runs between the lower rolls.

The wet paper supplied from the press section is wound around the upper cylinder rolls 1 and the lower cylinder rolls one by one in turn. The paper represented by the dotted line W shown in FIG. 1 is dried by cylinder rolls 1 and canvas 3 which are heated.

Eight motors 4A-4H are provided in a one-to-one relationship to eight canvas rolls 2A-2H. In this embodiment, motor 4A acts as the main motor while others act as auxiliary motors. The individual canvas rolls 2A-2H are coupled directly or via a reducer to the respective motors 4A-4H.

The cylinders 3 are driven by the canvas rolls 2A-2H so that the cylinder rolls 1A-1F are indirectly driven. Motor controllers 14A-14H are provided in a one-to-one relationship to motors 4A-4H. As will be described later, the main motor controller 14A controls the speed of the main motor 4A and the auxiliary motor controllers 14B-14H control the load torque of the auxiliary motors 4B-4H. Motor controllers 14A-14H control associated motors 4A-4H, respectively.

The main motor controller 14A includes a speed controller 7, an adder 9, a switching power supply 6 including a switching controller 6A and a chopper 6B, and a current detector 8 for detecting the output current of the switching power supply 6. The switching power supply 6 has, for example, an input terminal connected to the main power supply PS and an output terminal connected to the main motor 4A. The axis of rotation of the main motor 4A is connected to a speed sensor 5, eg a taco generator. The speed sensor 5 outputs a speed signal SS (also a function of the speed of feeding the paper W) corresponding to the rotational speed of the motor. This speed signal SS is supplied to the negative input terminal of the speed controller 7. In this papermaker, the signal SREF indicating the paper feed rate reference (system reference) is supplied to the plus input terminal of the speed controller 7 via a draw regulator 11 (voltage divider).

The adjustment value of the draw adjuster 11 is set in consideration of the draw given to the drying section, and the output signal DREF of the draw adjuster 11 represents a reference of the paper conveying speed in the drying section. The speed controller 7 calculates the difference between the speed signal SS and the reference signal DREF and outputs the speed control signal SC corresponding to the difference. The speed control signal SC indicating the amount of increase or decrease in the amateur current to be supplied to the main motor 4A is supplied to the adder 9 together with the output signal of the current detector 8.

The output signal of the adder 9 is supplied to the switching power supply 6. Based on the input signal, the switching controller 6A of the switching power supply 6 controls the output current of the chopper by controlling the on time (for PWM) and on frequency (for PFM) of the chopper 6B, thereby controlling the main motor 4A. The rotational speed thereof becomes equal to the rotational speed defined by the reference signal DREF. Current detector 8 detects the effective (average) current from main motor 4A and sends it to adder 9. Adder 9, switching power supply 6 and current detector 8 form a minor current loop.

Each auxiliary motor controller 14B-14H consists of a switching power supply 6, a current detector 8 and an adder 9 including a switching controller 6A and a chopper 6B. The speed control signal SC from the speed controller 7 of the main motor controller 14A is supplied to the load regulators 12B-12H provided to the auxiliary motors 4B-4H in a one-to-one relationship. The load regulators 12B-12H divide the received speed control signal SC into voltages according to the loads of the respective motors so that each trailing device receives the resulting signals MSC, which is a current indicating signal, respectively, and receives the output signal of its associated current detector 8. Send to guys 9. The switching controller 6A of the switching power supply 6 controls the on time, the on frequency, etc. of the chopper 6B by the output signal of the adder 9. The current detector 8 detects the output current of the power supply 6 and sends it to the adder 9.

In this embodiment, it is assumed that the total drying portion requires a driving force of 100 kw, the main motor requires a driving force of 30 kw, and each auxiliary motor requires a driving force of 10 kw. In this case, the signal output-to-input ratio of the load regulators 12B-12H is set to 1/3 (10/30). For example, if the signal SREF is represented as 600 m / min, the output signal DREF of the draw regulator 11 is set to a value representing 596 m / min.

The operation of the drying units arranged as shown in FIG. 1 will be described below.

Canvas rolls 2A-2H are rotated by motors 4A-4H and cylinder rolls 1A-1F and canvas 3 are indirectly driven by motors. The wet paper W supplied from the press section is dried while being alternately passed between the upper cylinder rolls 1D-1F and the upper canvas 3 and between the lower cylinder rolls 1A-1C and the lower canvas 3. The dried paper W is then sent to the calendar unit.

In this embodiment, in the steady state, the main motor 4A and the respective auxiliary motors 4B-4H are allotted 30 kw and 10 kw loads, respectively, and the wet paper W is transferred on the 2 A canvas at a speed of 596 m / min.

Consider the case where the paper feed speed becomes lower than indicated by the reference signal DREF due to the increase in load. The speed controller 7 obtains the difference between the reference signal DREF and the speed signal SS and outputs the speed control signal SC of a positive level corresponding to the difference. The adder 9 adds a signal representing the current currently supplied to the speed control signal SC and the main motor 4A and detected by the current detector 8. Based on the output signal of the adder 9, the switching controller 6A controls the on time, on frequency, etc. of the chopper 6B. In this embodiment, the level of the speed control signal SC is positive. The level of the output signal of the adder 9 is larger by the level of the speed control signal SC than the effective value of the current currently supplied to the main motor 4A. Therefore, the switching controller 6A increases the on time, on frequency, etc. of the chopper 6B, thereby increasing the effective value of the current to be supplied to the main motor 4A. The current detector 8 detects the active current supplied to the main motor 4A and supplies it to the adder 9, thereby performing the current mirror loop control. The control operation is repeated until the level of the speed control signal SC becomes zero. When the effective value of the current supplied to the main motor 4A increases, the torque of the motor 4A increases accordingly, so that the rotational speed of the motor 4A increases, whereby the speed indicated by the reference signal DREF becomes stable. As a result, the main motor 4A is driven at constant speed as defined by the reference signal DREF.

As mentioned above, in this embodiment, the signal output-to-input ratios of the load regulators 12B-2H are set to 1/3, so the level of the speed control signal SC from the speed controller 7 is reduced to 1/3, so that the auxiliary motor controllers Adders 9 of 14B-14H are supplied as signal MSC. Adders 9 are also supplied with signals from current detectors 8 representing the current values generated from switching power supply 6. In this embodiment, the level of the speed control signal SC is positive and the levels of the output signals of the adders 9 are higher by the level of the signal MSC than the corresponding values of the current values currently supplied to the auxiliary motors 4A-4H. Big. The switching controllers 6A of the power supplies 6 increase the on time, on frequency, etc. of the choppers 6B and thereby increase the effective value of the currents supplied to the auxiliary motors 4B-4H. The amount of increasing current here is different from that of the main motor controller 14A. Accordingly, drive current control (torque control) is performed.

The above operation is repeated until the level of the speed control signal SC becomes zero. The control system is stabilized when the rotational speed of the main motor A is equal to that indicated by the reference signal DREF.

Suppose the paper feed rate is greater than indicated by the reference signal DREF due to the reduction in load. In this case, consider the operation of the main motor controller 14A. The speed controller 7 outputs the speed control signal SC of voice level. The level of the output signal of the adder 9 is smaller by the level of the speed control signal SC than that corresponding to the effective value of the silver current currently supplied to the main motor 4A. The switching controller 6A reduces the on time, on frequency, etc. of the chopper 6B, thereby reducing the effective value of the current supplied to the main motor 4A. Now consider the operation of the auxiliary motor controllers 14B-14H, the level of the output signal of each adder 9 is higher by the level of the signal MSC than that corresponding to the effective value of the current currently supplied to the associated one of the auxiliary motors 4B-4H. small. The switching controller of each switching power supply 6 reduces the on time and on frequency of the associated chopper, thereby reducing the effective value of the current supplied to the associated auxiliary motor. This operation is repeated until the level of the speed control signal SC becomes zero.

With the above arrangement, even if the load varies, the main motor 4A can be controlled to drive at constant speed. The torques of the auxiliary motors 4B-4H are increased or decreased in accordance with the allocation ratio of the load of the auxiliary motors 4B-4H. As a result, the individual motors are always driven in a proper state, so that the paper to be dried can be stably transported without eventually tearing or creasing the paper.

A second embodiment of the present invention will now be described with reference to FIG. In FIG. 2, the components shown in FIG. 1 are given the same numerals and description is omitted. In addition, some components are omitted to simplify the drawings. The feature of the second embodiment is that the cylinder rolls 1A-1F are respectively driven by the motors 4A-4F. The control operation in this embodiment is substantially the same as that in which the specific control parameters have to be changed in the first embodiment.

Referring to FIG. 3, a third embodiment corresponding to the combination of the first and second embodiments as shown in FIGS. 1 and 2 will now be described. In this embodiment, the motors are provided in a one-to-one relationship to the canvas rolls 2B-2D and 2F-2H. Cylinder rolls 1A and 1D are mechanically coupled by gear 13 and driven by one motor 4A. The fourth embodiment is the same as that of the first embodiment in that the torque is controlled by using the motor 4A as the main motor and the torque is controlled in consideration of the load allocated using the other motors 4B-4H as the auxiliary motor.

Referring to Fig. 5, the fifth embodiment will now be described. In the first to fourth embodiments, the main motor is speed controlled and torque controlled in consideration of the load to which the auxiliary motors are allocated, but in the fifth embodiment, all the motors are speed controlled.

In this embodiment, motors 4A-4H are provided on canvas rolls 2A-2H respectively, and speed detectors 5A-5H and motor controllers 14A-14H are provided on motors 4A-4H in a one-to-one relationship. . The structure of the motor controllers 14A-14H is substantially the same as that of the motor controller 4A shown in FIG. These motor controllers 14A-14H commonly receive a reference signal DREF from draw regulator 11. The speed controller 7 of each of the motor controllers 14A-14H outputs the speed control signal SC based on the speed signal SS and the reference signal DREF from the association of the speed detectors 5A-5H. The adder 9 finds the sum of the signals representing the active currents from the current detector 8 associated with the speed control signal SC. The output signal from adder 9 controls the pulse width and pulse frequency of the associated switching power supply 6. Motor controller 14 selects one function to reduce the motor speed (i.e., the strong ability) with increasing load torque as shown in FIG. This function reduces the motor speed as the load increases so that the load allocated between the canvas rolls 2A-2H can be adequately maintained.

According to the first to fifth embodiments, by appropriately setting the drive capability of the individual motors, the drive system can continue its operation even if one motor or one motor controller is not operated. Now suppose that the driving capacity required for this motor is 100 kW for a conventional dryer which drives all rolls with a single motor. If the canvas rolls are driven by six motors each having a driving capacity of 22 KW, the total driving capacity is 6 × 22 = 132 KW. Even when one motor or motor controller is not running, the total drive capacity of the remaining motors is 110 KW, which is greater than the required drive capacity. Therefore, in this arrangement, the paper manufacturing process can be continued even when one motor or one motor controller is not operated.

In the above-described embodiments, the speed deviation is obtained and the effective value of the current output from the chopper is changed according to the speed, whereby the speed control and the torque control can be performed. However, the present invention is not limited to these embodiments. The motor controllers for performing the speed control and the torque control of the motors may be other known types of structures in addition to the above. For example, switching power supply 6 may be replaced with a conventional variable power supply or may not act as a chopper. The present invention may use AC motors and AC power supplies as well as DC motors and DC power supplies. For example, conventional structures for speed control and torque control of the motor can be used. That is, the frequency controller may be replaced with a switching power supply 6 for controlling the speed of the AC motor.

Claims (13)

A plurality of cylinder rolls, a plurality of canvas rolls, and canvases traveling between the cylinder rolls and the canvas rolls, the conveying means for drying the paper web to be dried while the paper web is being transported, and the cylinder A plurality of motors coupled to rolls and associated rolls of the canvas rolls, each of which drives at least one of the associated rolls to transfer and dry the paper web to be dried in a predetermined path, and the speed and load distribution of the motors Paper maker drying unit characterized in that it comprises motor controllers provided to each of the motors for individually controlling the. The speed detector of claim 1, wherein the speed detector for detecting the rotational speed of the first motor in the plurality of motors is coupled to the first motor, and the first motor controller for controlling the first motor includes: And the rotation speed of the first motor is controlled based on the output signal of the speed detector and the reference signal so that the rotation speed is equal to the speed indicated by the reference signal. 3. The paper maker dryer of claim 2, wherein motor controllers other than the first motor controller control the torques of the associated motors according to the load allocation ratio of the associated motors. 3. The method of claim 2, wherein the first motor controller calculates a difference between the rotational speed represented by the reference signal and the actual rotational speed of the first motor based on the output signal of the speed detector and the reference signal, and then And a speed difference detecting means for outputting a speed control signal corresponding to the speed control means and a speed control means for controlling the speed of the first motor based on the speed control signal. 5. The apparatus of claim 4, wherein each of the motor controllers other than the first motor controller comprises: compensation means for compensating the speed control signal from the speed difference detection means of the first motor controller by load allocation of an associated motor; And control means for controlling the current to be supplied of the associated motor based on the compensated speed control signal. 6. The apparatus of claim 5, wherein when the load of the associated motor is XKW and the load of the first motor is YKW, each of the compensating means multiplies the speed control signal from the first motor controller by X / Y; And torque control means for controlling an associated amateur current based on the X / Y-multiplied speed control signal. 2. The motor of claim 1, wherein each of the motors is coupled with a speed detector for detecting a rotational speed of an associated motor, and each of the motor controllers is equal to a rotational speed at which the rotational speed of the associated motor is defined by the reference signal. And controlling the associated motor on the basis of a reference signal and an output signal of the associated one of the speed detectors in consideration of a draw. 8. The motor controller of claim 7, wherein each of the motor controllers obtains a difference between the actual rotational speed of the motor associated with the rotational speed indicated by the reference signal based on the reference signal and the output signal of the associated one of the speed detectors. And a speed difference detecting means for outputting a speed control signal corresponding to the car and a speed control means for controlling the speed of the associated motor based on the speed control signal. 8. The paper maker dryer as claimed in claim 7, wherein the motor controllers each have a power to increase the torque and decrease the rotational speed. 2. The paper maker dryer of claim 1 wherein two of the plurality of rolls are mechanically coupled together and one of the plurality of motors drives the two combined rolls. The paper maker dryer of claim 1, wherein the sum of the driving capacities of the plurality of motors other than any one of the motors exceeds the driving capacities required to drive the plurality of canvases and the cylinder rolls. An upper stage having a plurality of cylinder rolls, a plurality of canvas rolls arranged in a staggered manner with the cylinder rolls, an upper stage having a canvas running between the cylinder rolls and the canvas rolls, the plurality of cylinder rolls, the A plurality of canvas rolls arranged in a staggered manner with the rolls, a canvas for traveling between the cylinder rolls and the canvas rolls, around the cylinder rolls of the upper stage and the cylinder rolls of the lower stage In a paper maker drying unit comprising a paper roll which is sequentially wound and dried by the cylinder rolls and the canvas, a driver for driving the cylinder and a lower stage having the canvas rolls, for driving the associated rolls. A plurality of motors connected to the associated at least one of the cylinder rolls and the canvas rolls, and one of the plurality of motors. Speed detector for detecting the rotational speed, means for comparing the predetermined reference signal with the output signal of the speed detector in consideration of the draw to obtain a difference between the actual rotational speed of the motor and the rotational speed defined by the reference signal And a first motor controller having speed control means for controlling an associated motor based on a signal corresponding to the difference to make the rotational speed of the one motor equal to the reference signal, and the plurality of motors other than the one motor. It is provided in a one-to-one relationship to the motors and receives and compensates the speed control signal from the first motor controller based on the ratio of the load of the associated motor and the load of the first motor to output the compensated speed control signal. And controlling the current supplied to the associated motor based on the compensated speed control signal. And a second motor controller for controlling the torque of said associated motor thereby having a control means for each. An upper stage having a plurality of cylinder rolls, a plurality of canvas rolls arranged in a staggered manner with the cylinder rolls, a canvas running between the cylinder rolls and the canvas rolls, a plurality of cylinder rolls, staggered with the rolls A plurality of canvas rolls arranged in a manner, a canvas for traveling between the cylinder rolls and the canvas rolls, and sequentially wound around the cylinder rolls of the upper stage and the cylinder rolls of the lower stage, In the paper maker drying unit comprising a lower stage having the cylinder rolls and the paper dried by the canvas, the driver for driving the cylinder and the canvas rolls, the cylinder rolls and the Associated at least one connected plurality of motors of the canvas rolls, and the rotational speed of the associated motors Corresponding to the difference by obtaining a difference between the speed detectors respectively provided to the motors and the output signals of the associated ones of the speed detectors and the reference signal, respectively, in consideration of a draw to detect them. Means for outputting a speed control signal, and means for varying the rotational speed of the associated ones of the motors according to the speed control signal so that the rotational speed of the associated motor is equal to the rotational speed defined by the reference signal. Paper maker drying unit characterized in that it comprises a motor controller having.

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