JPH0454305B2 - - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a reel motor control device for a tape leader with a reel, and more particularly, the present invention relates to a reel motor control device for a tape leader with a reel, and in particular, the tape is fed out from a feeding reel and wound on a take-up reel by a feeding side tensioner biased by a spring. The present invention relates to a device that controls a payout reel motor and a take-up reel motor so that a tension arm and a take-up side tension arm are tensioned, and both tension arms are maintained approximately in the center of their movable ranges.

Prior Art and Problems In general, in this type of control device, it is desired to control the reel motor with good responsiveness so that the tension arm does not exceed its movable range even when the tape is rapidly fed at high speed. Normally, this requirement can be met relatively easily if the reel motor's response and torque are sufficiently large relative to the load, but with the aim of lowering the price and downsizing the device, reel motors with small values are being developed. When used, since the torque is small relative to the load inertia, it takes too long to reach the rotation speed corresponding to the command voltage, and in some cases the tension arm may exceed its movable range, causing mechanical damage. It turns out.

A common way to improve this is to add advanced elements to the reel motor's feedback system. The advance element is, in other words, a differential element, which detects the acceleration of the tension arm and adds or subtracts a compensation value corresponding to the detected acceleration to or from the output value. Although this can be constructed with an analog circuit using an operational amplifier or a differential circuit, it is preferable to implement it with a digital circuit in order to ensure high reliability of the device. When implemented with a digital circuit, the output voltage of the potentiometer that detects the position of the tension arm is converted to A/D.
It is conceivable to import the value into the processor via a converter, compare the sampled value at regular intervals with the previous sampled value, and add or subtract the value corresponding to the difference from the current output value as an advanced compensation value. In this method, an A/D converter with an 8-bit resolution is used, and input data is sampled at about 1/100 to 3/100 of the arm change speed in order to improve control responsiveness.

However, for example, when a tape is fed at high speed, the tension arm moves through the movable range in about 100 ms, and if an A/D converter with an 8-bit resolution is used and the sampling period is 1 to 3 ms, the amount of change at each sampling is The number of output bits of the A/D converter becomes a very small value of 2 to 9 bits. On the other hand, the power supply voltage for the control device is 5V because many devices such as TTLIC are used. When using standard 5V to reduce the price and downsize the device, the potentiometer output is full scale 5V, and converting the above number of bits into voltage:
Since the value is 4mV to 18mV, which is close to the noise level, there is a drawback that the output value after compensation is strongly influenced by noise and fluctuates. In order to solve this problem, if the sampling period is lengthened, there will be a delay in the time for detecting a change in the position of the tension arm, which will cause a delay in correction, making it impossible to control the reel motor with good response.

Purpose of the Invention The present invention has been made in view of the above circumstances, and its purpose is to realize advance compensation that can detect changes in the position of the tension arm as quickly as possible while reducing the influence of noise. be.

Configuration of the Invention FIG. 1 is an explanatory diagram of the configuration of the present invention. tape
TP is paid out from a payout reel WL ₁ , taken up by a take-up reel WL ₂ , and tensioned by a payout side tension arm TA ₁ and a take-up side tension arm TA ₂ , which are biased by a spring SP. The rotational position of the tension arm TA ₁ on the feeding side is detected at predetermined intervals by a position detector DT ₁ such as a potentiometer and the tension arm position detecting means AR ₁ on the feeding side that processes the output thereof. The position information of the tension arm on the feeding side is stored in the position information storage means _ME1 . In addition, the tension arm on the winding side
The rotational position of TA ₂ is also determined by the position detector DT ₂ and the winding side tension arm position detection means that processes its output.
The AR ₂ detects the position information at predetermined intervals, and the position information of the past N or more times is stored in the winding side tension arm position information storage means ME ₂ . This storage means ME ₁ ,
The ME ₂ has a so-called FIFO register function that updates its contents at each predetermined period and always stores position information of the past N or more times at the current stage. The feeding-side compensation information calculation means CM ₁ multiplies the difference between the latest feeding-side tension arm position information and the most past feeding-side tension arm position information stored in the storage means ME ₁ by a predetermined value to obtain a compensation value. The winding-side compensation information calculation means CM ₂ multiplies the difference between the latest winding-side tension arm position information and the past winding-side tension arm position information stored in the storage means ME ₂ by a predetermined value. Proceed to find the compensation value. The output calculation means OS ₁ calculates the latest extension side tension arm position information stored in the storage means ME ₁ and the calculation means.
An output value that has been subjected to advance compensation is calculated from the compensation value from CM ₁ , and the payout reel motor MO ₁ is driven via the drive circuit DR ₁ . Also, output calculation means
The OS ₂ calculates the compensated output value based on the latest winding side tension arm position information stored in the storage means ME ₂ and the compensation value from the calculation means CM ₂ , and outputs it via the drive circuit DR ₂ . take-up reel motor
Drive MO ₂ .

In this way, in the present invention, sampling of the positional information of the tension arm TA ₁ on the feeding side and the tension arm TA ₂ on the winding side is performed, for example, at an interval of 1 ms to 3 ms, and the amount of change is calculated from the current value by 1 ms to 3 ms x N.
(N is 2 or more, preferably 3 to 4) Since it is calculated by comparing it with the previous value, even if the amount of position change per sampling period is small, the calculated amount of change will be a large value, and the noise level will increase. Since the proportion of the calculated amount of change is small, the influence of noise can be reduced, and the sampling time is 1 ms.
Since the change is calculated every ~3ms using the current value, changes in the tension arm position can be detected relatively quickly, and the response is relatively good, achieving the above purpose. Can be done.

Embodiment of the Invention FIG. 2 is a block diagram of essential parts showing an example of the hardware configuration of an embodiment of the invention. In the figure, 1 is a feeding reel, 2 is a feeding reel motor that rotates the feeding reel, and the paper tape 3 fed out from the feeding rail 1 is transferred to a fixed guide roller 4, a guide roller 6 of a feeding side tension arm 5, a fixed guide The brake shoe 10 is guided by a roller 7 between a light source 8 such as a light emitting element array and a light receiving element 9 such as a phototransistor array.
A capstan roller 12 rotated by a motor (not shown) between a brake magnet 11 that attracts zero
and a pinch roller 14 that moves vertically between the feed magnet 13 and feeds the paper tape 3 in cooperation with the capstan roller 12, and a fixed guide roller 15 and a tension arm on the winding side. It is guided by 16 guide rollers 17 and fixed guide rollers 18, and is wound up by a take-up reel 20 rotated by a reel motor 19. The feeding side tension arm 5 and the winding side tension arm 16 are biased by springs 21 and 22, respectively, and apply tension to the paper tape 3.

Furthermore, potentiometers 25 and 26 are attached to the rotation axis of the feeding side tension arm 5 and the rotation axis of the winding side tension arm 16, respectively.
The output is input to A/D converters 27 and 28. Note that one end of the fixed side terminals of the potentiometers 25 and 26 is connected to a 5V power supply, and the other end is grounded.

A microcomputer 29 is interconnected with peripheral circuits by a bus 30 including a data bus, an address bus, and a control bus.
The ROM 31 is a memory that stores necessary programs and the like, and the RAM 32 is a memory that has an area for temporarily storing the outputs of the A/D converters 27 and 28, a flag area, etc. The areas for storing the outputs of the A/D converters 27 and 28 are, for example, areas 27m ₅ and 28m ₅ for storing the latest position information, as shown in FIG. 3a and b.
and areas 27m ₄ , 28m ₄ , 27m ₃ , which store position information sampled 1 to 4 times before.
It has 27m ₂ , 28m ₃ , 28m ₂ , 27m ₁ and 28m ₁ . The output interface circuit 33 outputs the output value calculated by the microcomputer 29 to the drive circuit 35,
The drive circuits 35 and 36 convert the inputs into D/A to rotate the motors 2 and 19. The input interface circuit 34 is a circuit for connecting the outputs of the A/D converters 27 and 28 to the bus 30.

Figures 4 and 5 show the microcomputer 29.
This is a flowchart showing an example of the processing performed by the microcomputer 29, in which the microcomputer 29 executes the processing shown in FIG. 4 when an internal counter interrupts once every 3 ms, and executes the processing shown in FIG. 5 in the main routine.

In the interrupt processing, as shown in FIG. 4, the output processing (S1 to S10) of the A/D converter 27 and the A/D
Output processing (S11 to S20) of the D converter 28 is performed. The processing of the A/D converter 27 first begins with the A/D converter 27.
The output of the converter 27 is read and stored in the area _27m5 of the RAM 32 (S1), and the contents of the area 27 are transferred to the internal accumulator ACL (S2). Then the area
FIFO processing is executed to transfer the contents of _27m2 to area _27m1 , the contents of area _27m3 to area _27m2 , and the contents of area _27m4 to area _27m3 (S3). Then area 27m ₅
Subtract the contents of the accumulator ACL from the contents of and retain the value in the accumulator ACL (S4),
It is determined whether the value of the accumulator ACL is positive (+) (S5). If the value of the accumulator ACL is positive, the value of the accumulator ACL is multiplied by a predetermined value and the result is placed in internal register A to calculate an advance compensation value (S6). Also, RAM3
The flag _F1 provided at 2 is set and the compensation direction is stored (S7). On the other hand, if the value of the accumulator ACL is not positive, calculate the absolute value of the value of the accumulator ACL (S8), multiply the value by a predetermined value, and register ACL.
Then, the process proceeds to step 100, stores the compensation value (S9), resets the flag _F1 , and stores the compensation direction (S10).

Next, by performing the same processing as described above on the output of the A/D converter 28, the advance compensation value is obtained.
It is stored in the register B provided in the RAM 32, etc., and the flag _F2 is set according to the value of the accumulator ACL.
Perform a reset.

In the main routine, as shown in FIG. 5, a drive control process for the feed reel motor 2 consisting of steps S30-S33 and a drive control process for the take-up reel motor 19 consisting of steps S34-S35 are performed. The control of the feeding reel motor 2 is as follows.
First, the set/reset state of flag _F1 is determined to identify the compensation direction (S30), and if the compensation direction is positive, the contents of register A are added to the contents of area _27m5 (S31), and if negative, the contents of register A are added to the contents of area _20m5 . The contents of register A are subtracted from the contents (S32). This step S30~S32
advances and realizes compensation. Next, based on the obtained value, a digital amount to be sent to the drive circuit 36 via the output interface circuit 33 is calculated (S33).
For example, when the tension arm 5 on the feeding side is located at one end of the movable range, the A/D converter 27
When the output of is 0 and it is located at the other end, the output is 256,
If the position at the target location (approximately the midpoint of the range of motion) is 128, then from 128 step S31,
The value obtained in S32 is subtracted, and if the value is positive, the feed reel motor 2 is driven in the negative direction with a voltage proportional to the absolute value of that value, and if the subtracted value is negative, it is driven in the positive direction by the absolute value. Drive with a voltage proportional to . As a result, the drive circuit 36 rotates the feed-out reel motor 2 using the value obtained by converting the input into a D/A, and maintains the feed-out reel motor 2 at the target position.

The control of the take-up reel motor 19 is first performed using a flag.
Determine the set/reset state of _F2 and identify the compensation direction (S34). If the compensation direction is positive, add the contents of register B to the contents of area _28m5 (S35), and if negative, start from the contents of area _28m5 . The contents of register B are subtracted (S35). Next, the same processing as described above is performed based on the obtained value to calculate a digital value for driving, which is sent to the driving circuit 35 via the output interface circuit 33 (S33), and is input by the driving circuit 36. The take-up reel motor 1 is converted to D/A.
Rotate 9.

Effects of the Invention As explained above, according to the present invention, sampling of the positional information of the tension arm TA ₁ on the feeding side and the tension arm TA ₂ on the winding side is performed, for example.
Performed in 1ms to 3ms, and the amount of change is calculated from the current value.
1ms to 3ms×N (N is a value of 2 or more, preferably 3
~4) Since it is calculated by comparing with the previous value, even if the amount of position change per sampling period is small, the calculated amount of change will be a large value, and the proportion of the noise level in the calculated amount of change will be Because it is small, the influence of noise can be reduced, and since sampling is performed every 1ms to 3ms and the amount of change is calculated using the current value and the past value a predetermined number of times ago, changes in the position of the tension arm can be can be detected relatively quickly, and the responsiveness is also relatively good. Another method to reduce the influence of noise is to calculate the average value of the position information up to several times before, and calculate the compensation value based on the amount of change in this average value. The disadvantage of this process is that it requires a relatively large number of steps. In contrast, in the present invention, it is only necessary to find the difference between the current position information and the position information at a certain point in the past, which simplifies the processing and uses a so-called one-chip microcomputer with a small memory capacity to control the control unit. There is also the advantage that it can be realized.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the configuration of the present invention, FIG. 2 is a main block diagram showing an example of the hardware configuration of an embodiment of the present invention, and FIG. 3 is an explanatory diagram of a memory that stores position information of the tension arm. 4 and 5 are flowcharts showing an example of the processing performed by the microcomputer 29. FIG. 1, WL ₁ is the feeding reel, 2, MO ₁ is the feeding reel motor, 3, TP is the paper tape, 5, TA ₁ is the feeding side tension arm, 16, TA ₂ is the winding side tension arm, 19, MO ₂ is the take-up reel motor, 20, WL ₂ is the take-up reel, 25,
26, DT ₁ and DT ₂ are position detectors.

Claims (1)

[Claims] 1. A tape that is fed out from a feeding reel and wound up on a take-up reel is stretched between a feeding side tension arm and a winding side tension arm that are biased by a spring, and both tension arms are stretched within their movable range. A device for controlling a pay-out reel motor that drives the pay-out reel and a take-up reel motor that drives the take-up reel so that the pay-out reel is maintained substantially at the center, comprising: a pay-out reel motor control unit that controls the pay-out reel motor; a take-up reel motor control unit that controls a take-up reel motor; the pay-out reel motor control unit includes pay-out side tension arm position detection means that detects the current position of the pay-out side tension arm at predetermined intervals; a feeding-side tension arm position information storage means that stores detection information of the past N or more times of detection by the detection means and updates the contents at each predetermined period; and a feeding-side tension arm position information storage means that stores the latest detection information of the detection means at the predetermined period. a feeding-side compensation information calculation means for calculating a compensation value by multiplying the difference between the position information and the most recent feeding-side tension arm position information by a predetermined value; and the latest feeding-side tension arm position information stored in the storage means. and an output calculation means for calculating a compensated output value advanced from the compensation value, and a drive circuit for driving the feed-out reel motor with a value proportional to the output of the output calculation means, and a drive circuit for controlling the take-up reel motor. The section includes a winding side tension arm position detecting means for detecting the current position of the winding side tension arm at every predetermined period, and a winding side tension arm position detecting means for detecting the current position of the winding side tension arm at every predetermined period; A winding side tension arm position information storage means that updates the contents thereof, and a difference between the latest winding side tension arm position information stored in the storage means and the most past winding side tension arm position information. a winding-side compensation information calculating means for multiplying by a predetermined value to obtain a compensation value, and a winding-side tension arm position information stored in the winding-side tension arm position information storage means and the compensation value. A reel motor for a tape reader with a reel, comprising an output calculation means for calculating a compensated output value, and a drive circuit for driving the take-up reel motor with a value proportional to the output of the output calculation means. Control device.