JPS6249835B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a motor speed reference control device that continuously and smoothly changes the speed of a large number of motors in a continuous processing process for sheet materials such as paper, rubber, plastic, etc.

Generally, in the process of processing a sheet-like object, for example, a plurality of electric motors are arranged along a line to feed the sheet-like object, and the sheet-like object is processed between two successive electric motors. Then, the length of the sheet-like material is absorbed by the speed difference by driving the downstream electric motor at a higher speed than the upstream electric motor. Therefore, speed setting in a continuous processing line is an extremely important requirement, and conventionally, this type of control has been performed using analog methods. Generally, several to several dozen electric motors are used in continuous processing, but a conventional control device having three electric motors will be described below with reference to the block diagram shown in FIG. In Fig. 1, 1 is a line speed setting device that sets the speed of the entire line, 2 is a first speed difference setting device that sets a desired speed difference with respect to the line speed, and 3 is a first speed difference setting device. This is a second speed difference setting device for setting a desired speed difference with respect to the speed.
Further, 4, 5, and 6 are speed control devices for electric motors in each stage, and 7, 8, and 9 are electric motors in each stage. 1 more
0, 11, and 12 are acceleration/deceleration control circuits for each stage.
Generally, each electric motor 7, 8, 9 has a different acceleration/deceleration time depending on its load. Therefore, each acceleration time is set in the acceleration/deceleration control circuit, and the setting device 1,
In order to protect the machine from the wide and sudden speed reference given by 2 and 3, a control output that changes smoothly is obtained.

FIG. 2 is a block diagram showing yet another conventional example. In this case, the second speed difference setter 13 is configured to set a desired speed difference with respect to the line speed.

Therefore, in the conventional analog system, the first
As shown in the figure, speed control is performed by setting a speed difference for the front stage speed of each motor, and as shown in Figure 2, speed control is performed by setting the speed of each motor relative to the line speed. be. There is also a system that combines these two types of speed control.

By the way, conventional speed control will be explained in more detail with reference to the block diagram of FIG. 1 as follows.
That is, the respective speeds of the first stage electric motor 7, second stage electric motor 8, and third stage electric motor 9 are V _1(t0) and V _2(t0
) , V _3(t0) , and the respective speeds V _1(t3) , V _2(t3) ,
A case will be explained in which the speed is changed to V _{3 (t3)} . In this case, as shown in the speed change diagram shown in Figure 3, where the horizontal axis is time and the vertical axis is speed, first operate the line speed setting device 1 to set the first stage motor speed to V _{1 (t0
)} to V _1(t3) . If the completion time of this speed change is _t1 , at this point the second stage electric motor 8
The speed V _{2 (t0)} of the third stage electric motor 9 changes to V _{2 (t1)} , and the speed V _{3 (t0)} of the third stage electric motor 9 changes to V _{3 (t1)} . At the above time _t1 , the first speed difference setter 2 is operated to change the second stage motor speed from V2 _(t1) to V2 _(
t3) . If the completion time of this change is _t2 , the first stage motor speed remains at V1 _(t1) , but the third stage motor speed changes from _V3(t1) to _V3(t2) . Therefore, at time _t2 , the second speed difference setter 3 is operated to change the third stage electric motor speed from V3 _(t2) to V3 _(t3) in FIG. In this way, the line speed setting device 1, the first stage speed difference setting device 2, and the second stage speed difference setting device 3 are sequentially operated to change the speed. For this purpose, for example, in FIG. 3, the third stage motor speed is V _3(t0) →V _3(t1) →V ₃₍
There was a problem in that the speed fluctuated greatly from _t2) to V3 _(t3) and required a long time to settle to the desired speed.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a motor speed reference control device that controls the speed reference so that it changes linearly to the final speed value when the speed is changed.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the block diagram shown in FIG. That is, in this embodiment, each data is processed as a digital value, and at the final stage, the digital value is converted into an analog value, and the speed reference is passed to each control device. Note that it is of course possible to pass the speed reference to each control device as a digital value. In Fig. 4, 7, 8, and 9 are the first, second, and third stage electric motors, 14 is a digital line speed setting device, 15 is a digital first speed difference setting device, and 16 is a digital type line speed setting device. This is a second speed difference setting device. 17 is for reading the set values V, a, and b of the line speed setter 14, the first speed difference setter 15, and the second speed difference setter 16, and for generating gate signals for each series of digital arithmetic processing. This is the settings read push button. Then, 18 reads each set value V, a, b of the line speed setter 14, the first speed difference setter 15, and the second speed difference setter 16 by the signal of the setting read push button 17,
8,9 speed setting standard Vn _SET (n=1,2,3)
This is a set speed calculation circuit that calculates . and 1
9, 20, and 21 are speed standards of each actual speed standard Vn (n=1, 2, 3) of the 1st, 2nd, and 3rd stages and the above speed setting standard Vn _SET (n=1, 2, 3) This is a speed reference difference calculator that calculates the difference ΔVn (n=1, 2, 3). Furthermore, 22, 23, 24 are the acceleration/deceleration αn (n=1,
This is an acceleration/deceleration setting device that digitally sets parameters 2 and 3). 25, 26, and 27 are the speed reference differences ΔVn (n=1,
2, 3) and the above acceleration/deceleration αn (n=1, 2, 3)
The time required to change the speed Tn (n=1, 2,
3) is a speed change time calculator that calculates. 28
is the above speed change time Tn of the 1st, 2nd, and 3rd stage
This is a speed change time determining device that detects the longest time Tmax among (n=1, 2, 3). 29,30,3
1 is the speed reference difference ΔVn of the first, second, and third stages.
(n = 1, 2, 3) and the longest speed change time above
This is a determined acceleration/deceleration calculator that calculates the determined acceleration/deceleration αcn (n=1, 2, 3) of each of the electric motors 7, 8, and 9 based on Tmax. Also, 32, 33, 34
is the actual speed reference Vn (n=1, 2,
3) The above determined acceleration/deceleration αcn (n=1, 2,
3) and the above speed setting standard Vn _SET (n=
1, 2, 3) and finally match the actual speed reference output circuit. Note 4,
5 and 6 are speed control devices. The line speed setter 14, the first speed difference setter 15, the second speed difference setter 16, and the setting read push button 17 are attached to the operation desk on the field machine side. Therefore, the speed reference control device 35 is within the frame surrounded by the one-dot chain line in FIG.

The operation of the speed reference control device 35 will be described below with reference to speed change diagrams shown in FIGS. 4 and 5.
That is, as shown in FIG _.
) , V _2(t0) , V _3(t0) to V _1(t3) , V _2(t3) , V _3(t3
). Consider the case where the speed is changed to A method of setting a speed difference with respect to a previous stage speed reference as shown in FIG. 1 will now be described as an example. In FIG. 4, a new speed setting value V _{1 (t3)} for the first stage electric motor 7 is set in the line speed setting device 14. In addition, the new speed setting value V of the second stage electric motor 8 is input to the first speed difference setting device 15.
_2(t3) , a speed difference setting value a is set such that V _2(t3) =a·V _1(t3) . Similarly, a speed difference set value b is set in the first speed difference setter 16 so that V _{3 (t3)} = b·V _{2 (t3)} . Then, by pressing the setting read button 17, the set speed calculation circuit 18 calculates the speed setting standard for the first stage, V _{1 (t3) SET,} the speed setting standard for the second stage, V _{2 (t3) SET} = a× V _{1(t
3) SET} 3rd stage speed setting standard, V _3(t3)SET =b×V _{2(t
3) Calculate SET} , and when the calculation is completed, the next stage speed reference calculator 19,
20 and 21, and output a gate signal. The speed reference difference calculators 19, 20, and 21 calculate the speed reference difference for the first stage ΔV ₁ =V _1(t3)SET −V _1(t
0) Second stage speed reference difference ΔV ₂ =V _2(t3)SET −V _2(t
0) Speed reference difference for 3rd stage ΔV ₃ =V _3(t3)SET −V _3(t
0) is performed, and upon completion of the calculation, a transfer gate signal is output to the speed change time calculation units 25, 26, and 27 at the next stage.

Here, to simplify the explanation, the set values of the acceleration/deceleration setters 22, 23, and 24 are all set equal to α ₁ =α
₂ = α ₃ = α. speed change time calculator 25,
26 and 27 calculate the following: 1st stage speed change time T ₁ = ΔV ₁ /α 2nd stage speed change time T ₂ = ΔV ₂ /α 3rd stage speed change time T ₃ = ΔV ₃ /α , upon completion of the calculation, it is handed over to the next stage speed change time determiner 28, and a gate signal is output.
Now the acceleration/deceleration is α ₁ = α ₂ = α ₃ = α, so the sixth
As shown in the figure, the speed is changed directly at the acceleration/deceleration α. That is, according to Fig. 6, 1st stage speed change time T ₁ = t ₁ - t ₀ 2nd stage speed change time T ₂ = t ₁ - t ₀ 3rd stage speed change time T ₃ = t ₂ - t It becomes ₀ .

The speed change time determiner 28 determines each speed change time mentioned above.
As is clear from FIG. 6, the circuit that determines the longest time among T ₁ , T ₂ , and T ₃ determines the longest time Tmax=T ₃ . Then, the next stage determination acceleration/deceleration calculator 2
Data Tmax is delivered to 9, 30, and 31, and a gate signal is output. The determined acceleration/deceleration calculator 29,
30 and 31 are based on the maximum time Tmax and the speed reference differences ΔM ₁ , ΔM ₂ , ΔM ₃ 1st stage determined acceleration/deceleration αc ₁ = ΔV ₁ /Tmax 2nd stage determined acceleration/deceleration αc ₂ = ΔV ₂ /Tmax The three-stage determined acceleration/deceleration αc ₃ =ΔV ₃ /Tmax is calculated, and upon completion of the calculation, the data is transferred to the next-stage actual speed reference output circuits 32, 33, and 34, and a gate signal is output. Actual speed reference output circuit 32, 33, 3
4 has a sampling signal internally, and when one sampling occurs, 1st stage actual speed reference V ₁ = V ₁ + αc ₁ 2nd stage actual speed reference V ₂ = V ₂ + αc ₂ 3rd stage actual speed reference V ₃ = V ₃ Perform the calculation +αc ₃ . Here, V ₁ = V ₁ + αc ₁ is the sum of the speed change value per unit time of one sampling, that is, the determined acceleration αc ₁ , to the current actual speed reference V ₁ , and this is used as the new actual speed reference V ₁ . represent The actual speed references V ₁ , V ₂ , and V ₃ are delivered to the speed control devices 4, 5, and 6, respectively. Further, the actual speed reference output circuits 32, 33, and 34 output the speed setting standard V _1(t3)SET ,
When the values of V _{2 (t3) SET} and V _{3 (t3) SET} are reached, the above-mentioned calculation is stopped and held there, waiting until the next speed setting change request. Therefore, as shown in the speed change diagram shown in FIG. 5, the speeds of the first, second, and third stage electric motors 7, 8, and 9 change smoothly and linearly, and speed reference control of the electric motors is performed. be able to.

Note that the speed change time determining unit 28 is removed and the results of the speed change time calculating units 25, 26, 27 are directly delivered to the determined acceleration/deceleration calculating units 29, 30, 31, so that the speed is determined as shown in FIG. 6, for example. The criteria may be controlled.

Therefore, according to the control device of the present invention, the speed can be changed smoothly and the required time can be shortened. In addition, the amount of defective sheet material that occurs when changing speeds can be greatly reduced, and productivity can be significantly improved in continuous processing lines that frequently change speeds to produce various sheet materials, for example. can. Also, when performing operations, the first
In the conventional device shown in the figure, the line speed setting device,
In contrast to the need to operate the stage speed setter and second stage speed setter sequentially, in the present invention, after each set value is set, the speed can be changed using the setting read button, reducing the burden on the operator. It can be reduced. Note that the present invention may be configured using a programmable control device such as a microcomputer, and the above-mentioned effects can of course be achieved in this case as well.

As described in detail above, according to the present invention, it is possible to provide a motor speed reference control device that can smoothly change the speed in a short time, is easy to operate, and can reduce the burden.

[Brief explanation of the drawing]

1 and 2 are block diagrams showing different conventional control devices, FIG. 3 is a speed change diagram of the above conventional device, FIG. 4 is a block diagram showing an embodiment of the present invention, and FIG. 5 6 is a speed change diagram of the above embodiment, and FIG. 6 is a speed change diagram of another embodiment of the present invention. 4, 5, 6... Speed control device, 7, 8, 9...
Electric motor, 14, 15, 16...Speed difference setting device, 1
9, 20, 21...Speed reference difference calculator, 22, 2
3, 24... Acceleration/deceleration setting device, 25, 26, 27
... Speed change time calculator, 28... Speed change time determiner, 29, 30, 31... Determined acceleration/deceleration calculator, 32, 33, 34... Actual speed reference output circuit,
35...Speed reference control device.

Claims (1)

[Claims] 1 A plurality of electric motors, a speed control device that controls the speed of the electric motors, an actual speed reference output circuit that provides the final speed to the speed control device from the determined acceleration/deceleration and speed setting standards, and the actual speed of the electric motors and the speed mentioned above. A determined acceleration/deceleration calculator that calculates the determined acceleration/deceleration from the speed standard difference with the setting standard and the longest speed change time, and a speed that calculates the speed change time from the speed standard difference and the acceleration/deceleration set value of the acceleration/deceleration setting device. a speed change time calculator; a speed change time determiner that determines the longest speed change time from the speed change time of each of the motors by the speed change time calculator; a speed reference difference calculator that calculates the speed reference difference; In order to provide the speed setting standard to the speed standard difference calculating unit, the speed setting unit is provided with a set speed calculation circuit that calculates the speed setting standard of each of the motors from the speed setting device and the speed difference setting device, An electric motor speed reference control device characterized by performing control so as to smoothly change speed in the longest speed change time and lead to a final speed setting reference.