JPH0218191B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a center line for aligning the center lines of both strip materials when joining the rear end of the leading strip material and the leading end of the trailing strip material to obtain a long strip material. This invention relates to a matching device.

Heretofore, various devices for centering strip materials have been proposed, but none of them have been satisfactory as they have advantages and disadvantages. A general example thereof is shown in FIGS. 1 and 2. FIG. 1 is a plan view, in which 1 and 2 respectively indicate the leading and trailing strips to be joined;
a and 2a are the center lines of the leading strip material 1 and trailing strip material 2, respectively; 3 and 4 are the clamping mechanisms of the leading strip material 1 and trailing strip material 2, respectively; 5 and 6 are the leading strip material and trailing strip material, respectively. Reference numeral 7 indicates a moving frame movable in the width direction of the strip material, which is equipped with a clamping mechanism 4 and an edge detection mechanism 6 for the trailing strip material; 8 indicates an edge detection mechanism 5;
and a moving frame position control device which receives output signals from 6 and determines the position of the moving frame 7 in the width direction, and 9 controls the moving frame 7 by the output of the moving frame position control device 8 so that the centers of both strips coincide. This is a moving frame driving means for moving in the direction. The edge detection mechanisms 5 and 6 are installed parallel to each other between the fixed base 11, the supports 12a and 12b installed on the fixed base 11, and the supports 12a and 12b, as shown in the side view in FIG. 2, respectively. sliders 14a and 14b which slide on guide rods 13a and 13b via slide bearings 15a to 15d, respectively, and are connected to each other by racks 20a and 20b and pinions 21 meshing therewith; , sliders 14a and 1
A support plate 16a and 16b in which edge detection sensors 17a and 17b are embedded, each attached to one end of the support plate 16a and 16b, and a support plate 18 whose one end is attached to the backing plate 16a and the other end is attached to the fluid pressure cylinder 19.
The piston rod of the fluid pressure cylinder 19 is attached to the slider 14b. Also, the shaft of the pinion 21 is a potentiometer 2 for position detection.
It is linked to 2. The operation of the strip material centering device having the edge detection mechanism structured as shown in FIG. 2 is roughly as follows. When the rear end of the strip material 1 and the leading end of the strip material 2, which have been fed by a transport device (not shown), stop at predetermined positions, they are clamped by clamp mechanisms 3 and 4. Thereafter, when the hydraulic cylinder 19 is actuated to retract its piston rod, the sliders 14a and 14b, that is, the backing plates 16a and 16b attached to these ends are driven in a direction toward each other. As a result, the patch plate 16a or 16
Either one of b hits the edge of the strip material.
For example, when the strip material is in the position shown in FIG. 2, the backing plate 16b will hit first. If the cylinder 19 continues to operate further, the backing plate 16b
cannot move any further because it is in contact with the edge of the strip material, and the pinion 21 moves to the right in FIG. Plate 16a moves to the right and contacts the other edge of the strip of material. When both abutment plates come into contact with the respective edges of the strip material, an edge detection sensor detects this and stops the hydraulic cylinder. At this time, the axis of the pinion 21 is located on the center line of the width of the strip material because the backing plates 16a and 16b are connected by a rack and pinion mechanism. Therefore, the positions of the pinion shafts of the edge detection mechanisms 5 and 6 of the leading and trailing plates are detected by potentiometers connected to the shafts and input to the moving frame position control device 8, and both detection signals are detected. If the moving frame is driven by the driving means 9 according to the difference, the centers of both strips can be brought into alignment.

Such conventional devices have a simple structure and are widely put into practical use. The progress of the caul plate in contact with the strip is only hindered by the rigidity of the strip material, so if the strip material is thin or has low rigidity, one of the caul plates will After it comes into contact with one end edge, and until the other end comes into contact with it, the end edge of the strip deforms because it cannot resist the frictional resistance generated in the rack and pinion part, the slide part, etc., and the end edge of the strip appears to be This is the same as a change in position, making accurate detection impossible.

In order to overcome these drawbacks of conventional devices, a device has been proposed that detects the edge in a non-contact manner and calculates the obtained position signal to calculate the center position, correction amount, and direction of the strip material. Complex arithmetic processing was required and the equipment became expensive, making it impractical.

The present invention detects the amount of movement of each edge detector by the number of pulses, receives the output pulses from the detectors with a single counter, and calculates the direction and amount of correction for centering the strip material. We have proposed an extremely simple and accurate centering device that detects this as a count result of a counter and also feeds back the amount of correction to the same counter when correcting the position of the strip material. .

FIG. 3 is a plan view showing an embodiment of the present invention.
In the figure, parts having the same functions as those in FIG. 1 are given the same reference numerals. Unlike the case shown in FIG. 1, the trailing strip material 2 edge detection mechanism 6' is fixed to the strip conveyance line separately from the trailing strip material clamping mechanism 4'. Further, the trailing strip material clamping mechanism 4' is configured to be movable in the width direction of the strip material by a feed screw rod 92 rotated by a driving electric motor 91. The amount of movement of the clamp mechanism 4' is converted into pulses by the detector 93 and fed back to the control device 8'. FIG. 4 is a side view of the edge detection mechanism 5' for the leading strip 1 in the embodiment shown in FIG. 3, and the edge detection mechanism 6' for the trailing strip 2 has a similar structure. In the figure, 51a, 5
1b is a sensor for detecting the edge of a strip material, and is fixed to sensor mounting tables 52a and 52b. The sensor mounting tables 52a and 52b are connected at the center and engaged with a feed screw rod 53 having screws in opposite directions, and are moved toward and away from each other by equal distances by rotation of the feed screw rod 53. do.
The feed screw rod 53 has bearings 54a to 54c.
and rotated by an electric motor 55. This amount of rotation is determined by the sensor 51 by the detector 56.
The pulses are converted into a number of pulses corresponding to the amount of movement of a and 51b, and are supplied to the control device 8' in FIG. When the sensors 51a, 51b approach the sensor mounting tables 52a, 52b due to the rotation of the electric motor 55, they come into contact with the strip material, the actuator rotates, and the contacts of the built-in switches close. In this switch, when the sensor mounting tables 52a and 52b approach further, the actuator goes under the strip and continues the closed state. The operation of the embodiment shown in FIGS. 3 and 4 will be explained with reference to FIG. FIG. 5 schematically shows the above embodiment, and the reference numerals in the figure correspond to the reference numerals in FIGS. 3 and 4. Further, 61a and 61b are sensors for detecting the edge of the trailing strip material 2, 63 is a feed screw rod, 65 is a driving motor, and 66 is a sensor movement amount detector. In FIG. 5, a leading strip 1 of width W ₁ and a trailing strip 2 of width W ₂ are shown.
are the edge detection sensors 51a, 51b, 61, respectively.
Assuming that they are at a distance of l ₁ to l ₄ from the open ends of the strips a and 61b, respectively, the deviation amount Δl of the center position of both strips is based on the left end of the figure: Δl = (l ₁ +1/2・W ₁ )−( l ₃ +1/2・W ₂ )...
…(1). Therefore, when using the left end of the figure as a reference, if Δl in equation (1) is positive, the center of strip material 1 is to the right of the center of strip material 2, and if it is negative, as shown in FIG. It will be on the left. If the edge detection sensors of the leading and trailing strips are all arranged at the same distance from the center of the device, then l ₁ + l ₂ + W ₁ = l ₃ + l ₄ + W ₂ ...(2) So, by substituting this into equation (1), Δl=1/2(l ₁ −l ₂ )+1/2(l ₄ −l ₃ )……(
3), and is independent of the widths W ₁ and W ₂ of the strip material. Therefore, in FIG.
By rotating and 65 and moving the sensors 51a, 51b and 61a, 61b inward until each sensor detects the edge of each strip, and measuring the amount of movement of each sensor at this time, the above formula (3) can be obtained. l ₁ to
l ₄ variables are obtained. In this case, each value of l ₁ to l ₄ may be detected, but if the structure is as shown in FIG.
Since a and 61b are each moved the same distance by a common feed screw rod, the feed screw from when the first sensor of each set detects the edge until the remaining sensors detect the edge. By detecting the amount of rotation of the rod, |l ₁ −l ₂ | or |l ₃ −l ₄ | can be directly obtained. At this time, the direction of deviation of the strip material from the center of the device can be determined by the sensor that first detects the edge of each set of sensors. Therefore, the sign and value of the center position difference Δl are determined by the distinction of the sensor that first detected the edge and the values of |l ₁ −l ₂ | and |l ₃ −l ₄ |.

FIG. 6 shows an embodiment of the control device 8' in the apparatus of FIG. 3 constructed as shown in FIG. In the same figure, 81 is a multilayer pulse oscillator, and in the case of FIG. For the B phase, an oscillator is used that generates pulses of different phases that do not overlap each other and whose period is shorter than the width of the output pulses of the sensor movement amount detectors 56 and 66. 82,8
3 is a pulse synchronization circuit that generates a single pulse for each pulse of the output of the sensor movement amount detectors 56 and 66 in synchronization with the output of the multiphase pulse oscillator 81;
AND1 or AND10 is an AND gate, OR1
and OR2 is an OR gate, FF1 to FF4 are R-S flip-flop circuits, and IN1 is an inverter. 84 is an up-down counter that counts input pulses in binary code; 85 is an absolute value conversion circuit that receives the output of the up-down counter 84 and converts 1/2 of this output value into an absolute value; 86;
is a zero detection circuit, and when the output of the up-down counter 84 becomes zero, the flip-flop circuit is activated.
Outputs a reset signal to FF4. Reference numeral 87 denotes a display device which inputs the highest digit output of the up-down counter 84 and the output of the absolute value conversion circuit 85 and displays the distance Δl between the center positions of both strips together with its direction. 88 is a push button switch for starting strip position detection, and 89 is a push button switch for starting strip position correction operation. Terminals A and B are output terminals to the control device for electric motors 55 and 65 (not shown), and terminals C and D are output terminals to the control device for electric motor 91 (also not shown). Here, the AND gates AND1 to AND4 and the OR gates OR1 and OR2 transmit the output pulses of the movement amount detectors 56 and 66 to the sensor 51a,
This is a discrimination circuit for determining which pulses are to be added or subtracted according to the detection order of 51b, 61a, and 61b. When the push button switch 88 is pressed to start detecting the position of the strip material, the flip-flop circuits FF1 and FF2 are set and the counter 84 is reset. As a result, H signals appear at output terminals A and B, which are the Q outputs of flip-flop circuits FF1 and FF2, and motors 55 and 65 start rotating by a motor control device (not shown). As the electric motors 55 and 65 rotate, the feed screw rods 53 and 63 rotate,
The strip material edge detection sensors 51a, 51b and 61a, 61b are driven toward each other. The amount of movement of each sensor at this time is
6 and 66, the number of pulses corresponding to the amount of movement is supplied to pulse synchronization circuits 82 and 83, and is synchronized with the output pulses of each phase of the multiphase pulse oscillator 81 and output to AND gates AND1 to AND4.
supplied to Edge detection sensors 51a, 51b,
While neither 61a nor 61b detects the edge of the strip material, the AND gates AND1 to AND4 are closed, and the outputs of the pulse synchronization circuits 82 and 83 are not transmitted to subsequent circuits. As each sensor approaches further, each sensor sequentially detects this in accordance with the position of the strip material. When the strip material 1 is located in the state shown in FIG. 5, the sensor 51a first detects the strip material. This detection signal opens the AND gate AND2, and from then on, the output of the movement amount detector 56 inputs the pulse synchronized by the A-phase pulse of the multiphase pulse oscillator 81 to the down count terminal of the counter 84, and then outputs a negative value. Count. When the electric motor 55 further rotates and the sensor 51b also detects the edge of the strip material 1, the AND gate AND5 opens and the flip-flop circuit FF1 is reset. As a result, the output of the output terminal A is inverted and becomes L, and the motor 55 stops and the AND gate AND
Close 2. In this case, the AND gate AND1 does not open between the start and stop of the electric motor 55. If the strip material 1 is located to the right of the center in FIG.
4 receives a pulse corresponding to the distance moved by both sensors at the up count terminal until the sensor 51a detects the edge, and performs a positive count, and in this case, the AND gate AND2 does not open. On the other hand, since the electric motor 65 also starts rotating at the same time, the sensor 61
The movement amount detector 66 generates a pulse according to the movement amount of the sensors 61a and 61b, and the pulse synchronization circuit 83 converts it into a pulse synchronized with the B-phase pulse of the multiphase pulse oscillator 81. AND gates AND3 and AND4 both remain closed until one of them detects the edge of the strip material, and when the strip material 2 is in the position as shown in FIG. is detected, the AND gate AND4 opens and transmits the pulse of the pulse synchronization circuit to the down count terminal of the up/down counter 84. This state continues until the electric motor 65 rotates further and the sensor 61a detects the edge. Here, A of the multilayer pulse oscillator 81
If the oscillation period of each phase of and B is set as a two-phase pulse that has a period shorter than the pulse width generated by the sensor movement amount detectors 56 and 66 and does not overlap with each other,
Since each output of pulse synchronization circuits 82 and 83 is synchronized with this, the two outputs do not overlap.
As shown in FIG. 6, the outputs of sensors 51a, 51b, 61a and 61b are connected to
When connected to AND4, in the schematic diagram of Fig. 5, when l ₁ < l ₂ , it is connected to AND gate AND2 |l ₁ −
When l ₂ |, l ₁ > l ₂ , the AND gate AND1 becomes |l ₁ −
When l ₂ | is l ₃ < l ₄ , it is converted to AND gate AND3 | l ₃ −
l ₄ |, but when l ₃ > l ₄ , it becomes an AND gate AND4 |l ₃ −
l ₄ | is output. Therefore, the outputs of the AND gates AND1 and AND3 are connected to the up terminal of the up-down counter, and the outputs of the AND gates AND2 and AND3 are connected to the up terminal of the up-down counter.
When the output of AND4 is supplied to the down-count terminal of the up-down counter 84, the up-down counter 84 counts the number of pulses corresponding to 2Δl = (l ₁ - l ₂ ) + (l ₄ - l ₃ ) along with their signs. That will happen. When the trailing strip material 2 is on the right side of the figure with respect to the leading strip material 1 as shown in FIG. Therefore, the counter 84 has −|l ₁ −l ₂ |−|l ₃ −l ₄ |=−|(l ₁ −
l ₂ ) + (l ₄ - l ₃ )}=-2Δl is counted, and the negative sign indicates the strip material 1
and 2 have the relationship shown in Figure 5.

Here, the value Δl of the deviation between the center positions of the strip materials 1 and 2 is determined by using a binary counter as the counter 84, excluding the lowest digit, and converting each digit above the second digit by one digit to the immediately lower digit. If it is connected so as to carry it down and supply it to the absolute value conversion circuit 85, 1/2 of the contents of the counter 84 can be obtained without performing calculations.
value is obtained. In addition, if the counter 84 has a capacity larger than the number of pulses corresponding to the maximum movement distance of the sensors 51a to 61b, and the counter 84 is prevented from overflowing when the sensors are moved, the result shown in FIG. Since the maximum digit indicated by the MSB is 0 when the count result is positive and 1 when the count result is negative, it is possible to determine whether the count contents are positive or negative from the state of the MSB. Further, the absolute value conversion circuit 85 obtains the absolute value of the input signal and converts it into a decimal code, or displays it on the display 87.
has a conversion function, it is transmitted as is to the display 87, and the display 87 outputs the MSB of the counter 84.
It is displayed with positive/negative or left/right signs depending on the signal from.

When the above-described position detection operation of the strip material by the edge detector is completed, the electric motors 55 and 65 are reversed by an appropriate means (not shown) to detect the sensor 5.
1a to 61b are retracted, but at this time flip-flop circuits FF1 and FF2 are in the reset state, so the rotational speed of the feed screw rods 53 and 63 during this retracting operation is detected by the movement amount detector 5.
6 and 66, this pulse is not transmitted to the counter 84.

When the evacuation of each sensor is completed, push the correction start pushbutton switch 89 and remove the strip materials 1 and 2.
Start correcting the misalignment. When pushbutton switch 89 is pressed, flip-flop circuit FF3 is reset and flip-flop circuit FF4 is set. In this case, the highest digit output of the counter 84
If the MSB is 0, that is, the count result is positive, flip-flop FF3 remains reset, but if the count content is negative, the flip-flop circuit
The FF3 enters the set state when the push button switch 89 is released. Now, the case where the output of the counter 84 is a positive count will be explained. counter 8
If the content of 4 is positive, the flip-flop circuit is in a reset state, so its Q terminal becomes L.
In response to the Q terminal output of flip-flop FF4 and the output of inverter IN1 which is an inversion of the output of flip-flop circuit FF3, AND gate AND9 opens, while AND gate AND10 closes.
As a result, an H output appears at the output terminal C, and the motor 91 rotates in a direction to move the trailing strip material clamping mechanism 4' to the right in the figure. According to this rotation, the detector 93 generates a number of pulses corresponding to the amount of movement, and these pulses are transmitted to the down count terminal of the counter 84 via an AND gate AND8 and an OR gate OR2, and are subtracted from the count contents of the counter 84. It acts on If the strip materials 1 and 2 are located in the relationship shown in FIG. 5, the contents of the counter 84 will be negative, so the AND gates AND7 and AND10 will open and move the clamping mechanism 4' to the left in the figure. The amount is provided to the up count terminal of counter 84. Here, as mentioned above, since the contents of the counter 84 indicate 2·Δl, the number of output pulses of the detector 93 is set to generate twice the number of pulses for the same moving distance to the detectors 56 and 66. Configure it. As the electric motor 91 rotates, the contents of the counter 84 decrease and when it reaches zero, the zero detection circuit 86 detects this and activates the flip-flop circuit.
Reset FF4. This result and gate
AND9 closes, motor 91 stops, and the position correction operation ends.

Here, the pulse synchronization circuits 82 and 83 input the outputs of the movement amount detectors 56 and 66 and the output of the multiphase pulse oscillator 81, respectively, and generate a multiphase pulse oscillator for each output pulse of the movement amount detectors 56 and 66. Any device that generates one pulse synchronized with the output pulse of 81 is sufficient, and an example thereof is shown in a block diagram in FIG. In Figure 7,
FF5 and FF6 are D-type flip-flop circuits, AND11 is an AND gate, and TD1 is a delay circuit. The operation when the example shown in FIG. 7 is used for the pulse synchronization circuits 82 and 83 will be explained with reference to the waveform diagram in FIG. 8. FIG. 8 is a waveform diagram showing the input/output relationship of the pulse synchronization circuit of FIG. These are input pulses from the movement amount detectors 56 and 66, and the width of the pulses corresponds to the movement speed of each edge detection sensor. Normally, these pulses have approximately the same pulse width, but this is exaggerated in the figure. e is the Q output of the D-type flip-flop circuit FF5 triggered in synchronization with the A-phase pulse, f
is the Q output of the flip-flop circuit FF6 which is triggered by the delay circuit TD1 with a delay of time tp from the A phase, g is the output of the AND gate AND11,
This output becomes the output of the pulse synchronization circuit 82.
h indicates the output pulse of the pulse synchronization circuit 83 synchronized with the B-phase pulse similarly obtained. First, the operation of the pulse synchronization circuit 82 that synchronizes input pulses from the movement amount detector 56 will be described. 8th
As shown in FIG. When is input to the C terminal, the flip-flop circuit FF5 is set and its Q terminal output becomes H. This flip-flop circuit FF5 is inverted and becomes L at the rise of the next C terminal input pulse after the D terminal input becomes L. On the other hand, the A-phase output pulse of the multiphase pulse oscillator is timed by delay circuit TD1.
The signal is delayed by tp and is supplied to the C terminal of the D-type flip-flop FF6. At this time, if the D terminal input is L, the flip-flop circuit FF6 is reset at that point, and the Q output becomes L. Therefore, the AND gate AND11 generates a pulse for a period tp from the time when the A-phase pulse of the multiphase pulse oscillator 81 is input and the flip-flop 5 is set until the flip-flop circuit FF6 is reset. Next, even if the A-phase pulse of the multiphase pulse oscillator 81 is input, the D of the flip-flop circuit FF5 is
The terminal does not invert as long as the pulse from the movement amount detector 56 continues. flip-flop circuit
This is the D terminal input of FF5. This state continues until the output pulse of the movement amount detector 56 disappears, and eventually the output of the AND gate AND11, that is, the output of the pulse synchronization circuit 82, is supplied first after the rise of the output pulse of the movement amount detector 56. A single pulse having a width tp synchronized with the A-phase pulse from the multiphase pulse oscillator 81 is generated as shown in FIG. 8g. Similarly, the output pulse of the movement amount detector 66 is synchronized with the B-phase pulse of the multiphase pulse oscillator 81 by the pulse synchronization circuit 83 as shown in FIG. 8h.
This results in a single pulse of tp. At this time, the output pulses from the multiphase pulse oscillator 81 are configured so that they do not overlap each other in the A phase and B phase, and the period thereof is shorter than the output pulse width of the movement amount detectors 56 and 66, and If the delay time of the delay circuit TD1 is set to be shorter than the time difference between the A-phase and B-phase pulses, the output pulses from the movement amount detectors 56 and 66 will be mutually independent regardless of the timing of generation of these pulses. It is converted into pulses that do not overlap.

The edge detection mechanism for the strip material may be provided with a drive mechanism and a movement amount detector for each detection sensor in addition to those shown in FIGS. 3 to 5. FIG. 9 shows an example of such a case using a schematic diagram similar to FIG. 5. In the same figure, strip material edge detection sensors 51a, 51b, 61a and 61b are operated by dedicated electric motors 55a and 55, respectively.
b, 65a and 65b, respectively, and the amount of movement is determined by the amount of movement detectors 56a, 56b, 66a and 66b provided respectively.
is detected as the number of pulses corresponding to the amount of movement. In the example of FIG. 9, each sensor is driven by a separate drive mechanism, so it is sufficient to stop each sensor when it detects the edge of strip 1 or 2. Each displacement detector generates a number of pulses corresponding to the distance from each sensor's outermost position or preset position to its stop position.

FIG. 10 is a connection diagram showing an example of a control device in which the strip edge detection mechanism is configured as shown in FIG. 9. In the figure, components corresponding to those in FIG. 9 are given the same reference numerals. 81' is a multiphase pulse oscillator similar to the embodiment shown in FIG. 6, but since there are four movement amount detectors, A, B, C,
A four-phase pulse oscillator that generates four pulses with different phases from each other is used. Also, AND12 to AND15 are AND gates, OR3 and OR4
is an OR gate, FF1a, FF1b, FF2a and FF2b are R-S flip-flop circuits, 82
a, 82b, 83a and 83b are pulse synchronization circuits corresponding to numerals 82 and 83 in the embodiment shown in FIG. 94 is a setting device including a digital ital switch for setting the position at which the moving speed of the movable clamp 4' is reduced during correction; 95;
is a comparator which compares the output Δl of the absolute value conversion circuit 85 with the set value of the setter 94 and outputs a deceleration signal to the output terminal 96 when the two match. 10th
In the illustrated embodiment, movement amount detectors 56a, 56
The discrimination circuit for discriminating the outputs of 66a and 66b into addition or subtraction signals is an OR gate.
It is composed of OR3, OR4 and their related input/output connections, and the output pulses of the movement amount detectors 56a and 66b are sent to the up count terminal of the counter 84, and the output pulses of the movement amount detectors 56b and 66a are sent to the up count terminal of the counter 84. 2・Δl=(l ₁ −
l ₂ ) + (l ₄ − l ₃ ). In the same figure, AND gates AND12 to AND15
The movement amount of each sensor is input to the counter 84 only from when one sensor detects an edge to when the other sensor detects an edge, and also prevents pulses from being erroneously generated when the sensor is retracted. These AND gates are gate circuits to prevent overloading and counting.If the operation procedure is set so that each sensor is not evacuated until the position correction is completed, these AND gates will only change the counting period of the counter, but the final count result will be the same. Therefore, it can be omitted. Further, terminals H to H are output terminals to a control device (not shown) that controls the rotation of the electric motors 55a, 55b, 65a, and 65b. In the embodiment shown in FIG. 10, similarly to the embodiment shown in FIG.
b is set, and at the same time the counter 84 is reset. As a result, the sensor drive electric motors 55a, 55b, 65a and 65b shown in FIG.
1b respectively move inward in the figure. When each sensor detects the edge of the strip material, the flip-flop circuits FF1a to FF2a are reset and stopped. At this time, the movement amount of each sensor is determined by movement amount detectors 56a, 56b, 66a and 66b.
The number of pulses corresponding to the distance traveled is detected by the pulse generator and supplied to the AND gates AND12 to AND15. These AND gates are provided with edge detection sensors 51a, 51b, 61a and 6, respectively.
1b and flip-flop circuit FF1
Since the Q terminal outputs of a to FF2b are supplied, the sensors 51a and 51b or the sensor 61a constituting each sensor set
and AND gate AND12 or AND13 or AND14 or AND15 is opened from when one of them detects the edge of the strip material to when the other detects the edge of the strip material, and the amount of movement of the sensor during that time. Accordingly, the pulse train corresponding to the terms (l ₁ - l ₂ ) and (l ₃ - l ₄ ) in the third equation is passed through the AND gates AND12 to AND15 to the pulse synchronization circuits 82a, 82b, 83a and 83b. Supplied. Pulse synchronization circuit 82a
In input pulses 83b to 83b, the input pulses are converted into pulses synchronized with each phase pulse of the multiphase pulse oscillator 81' and supplied to OR gates OR3 and OR4. The output of the pulse synchronization circuits 82b and 83a, that is, the output of the movement amount detectors 56b and 66a, is supplied to the down-count terminal of the counter 84. Here, the period of the A phase to D phase of the multiphase pulse oscillator 81' is the same as that of the movement amount detectors 56a, 56b, 66a and 66a.
If the value is set to be smaller than the narrowest pulse width of each output pulse of 6b and the pulses of each phase do not overlap with each other, the output pulses from each detector will be as shown in Fig. 8. Similarly, one pulse is necessarily converted into a single pulse with no overlap by the synchronizing pulses of each phase of the multiphase pulse oscillator 81'. Therefore, the counter 84 has 2Δl=(l ₁ −l ₂ )+(l ₄ −
The pulses corresponding to l ₃ ) are counted exactly with their sign. The contents of the counter 84 are reduced by one digit and supplied to the absolute value converting circuit 85 to become a 1/2 value, that is, the value Δl, and are inputted to the display 87 together with the MSB signal of the highest digit of the counter 84, and the center of both strips is inputted. The distance Δl between positions is displayed together with its sign. When the value of distance Δl is detected in this way, electric motors 55a, 55b, 65a and 65
b is reversed to retract the sensors 51a, 51b, 61a and 61b. Next, when the pushbutton switch 89 is pressed to correct the position of the strip material, the flip-flop circuit FF4 is reset and the AND gate AND9 or AND10 opens according to the count contents of the counter 84.
is rotated in the direction in which Δl decreases to move the movable clamp 4'. Due to this operation, the amount of correction is
3 and fed back to the counter 84. When the content of the counter 84 decreases and reaches the preset value of the setter 94, the comparator 95 issues a deceleration command and decelerates the motor 91 to a sufficiently low speed so that no error occurs when stopping. When the correction progresses further and the contents of the counter 84 become zero, the zero detection circuit 86 detects this and resets the flip-flop circuit FF4, and the AND gate AND9,
AND10 is closed to stop the electric motor 91. At this time, the accuracy can be further improved by setting the zero detection circuit 86 to a value other than zero that takes into account errors caused by overrun or backlash of the drive mechanism.

The embodiments shown in FIGS. 3 to 10 are specific examples of the apparatus of the present invention, and
The present invention is not limited to these embodiments and can be modified in various ways. In particular, the circuit for supplying the output pulses of the movement amount detector of each sensor to the counter in the above embodiment is configured such that the difference in center position of each strip with respect to the left end of the figure in the arrangement shown in FIGS. 5 and 9 is This is a connection diagram for detecting and correcting by the above-mentioned formula (1). When the detection criteria for the strip center position is different, the formula (1) is also different, so the signal that is compatible with them is Of course, it is necessary to change connections and assign meanings to each signal in order to handle it. Furthermore, in the embodiment shown in FIG. 6, a setting device 94 and a comparator 95 for presetting the deceleration position may be provided in the same manner as in the embodiment shown in FIG. The sensor uses a contact type switch as shown in the figure, as well as a non-contact type switch such as a proximity switch or a photoelectric switch, or if the strip material is conductive, the sensor may be a contact type switch such as a proximity switch or a photoelectric switch. It may also be of a type that detects this based on electrical continuity. Further, two pushbutton switches 88 for starting strip position detection may be provided so as to detect each of the leading and trailing strips independently, or the pushbutton switch 88 can be closed in response to a signal indicating completion of clamping the strip material. It is also possible to perform automatic operation in place of traffic lights.
In addition, the positions of both the leading and trailing strip materials are detected and a signal is sent to the push button switch 88 and flip-flop circuits FF1, FF2 or FF1a, FF1.
By using the push button switch 89 for starting correction of the trailing strip position obtained from FF2b, FF2a and FF2b, the correction operation can be automatically started following position detection. Furthermore, the corrective action for aligning both strips was performed by moving the clamping mechanism of the trailing strip in the above embodiment, but this was done by moving the clamping mechanism of the leading strip. Alternatively, the clamping mechanisms for both the leading and trailing strips may be moved. In addition to the drive mechanism shown in the drawings, the clamp mechanism and the drive mechanism for each sensor may be of a rack and pinion type or a pressure responsive mechanism using a hydraulic cylinder and a servo valve. Additionally, Figures 6 and 10
The control circuit shown in the figure may be configured by logic elements or may be provided with similar functions by program designation using a small information processing unit such as a microprocessor.

As described above, the centering device of the present invention includes a pulse synchronization circuit that simply shapes the amount of movement of the edge detection sensor of each strip material so that the pulses do not overlap each other, and a pulse synchronization circuit that simply shapes the amount of movement of the edge detection sensor of each strip material until each sensor detects the edge of the strip material. The widthwise direction of the center position of both the leading and trailing strip material is simply guided to a single up-down counter via a discrimination circuit that determines the amount of movement between as an addition or subtraction signal. Not only can the device be inexpensive because it can directly detect the difference in the strip material, but the strip edge detection sensor simply obtains a signal of the presence of the strip edge, so it does not require other mechanisms like conventional devices. Since it is not moved by the drag force based on the rigidity of this edge, even a non-contact type sensor as well as a contact type sensor can detect this with a minute force. Since it does not deform, extremely high detection accuracy can be obtained.

[Brief explanation of drawings]

Figure 1 is a plan view of a conventional centering device, Figure 2 is a plan view of a conventional centering device;
The figure is a side view of an edge detection mechanism used in the conventional device shown in FIG. 1, FIG. 3 is a plan view showing an embodiment of the centering device of the present invention, and FIG. 4 is an edge detection mechanism in the embodiment shown in FIG. A side view of the detection mechanism, FIG. 5 is an explanatory diagram schematically shown to explain the function of the device in the embodiment shown in FIG. 3, and FIG. 6 is applied to the embodiment shown in FIGS. 3 to 5. 7 is a block diagram showing an embodiment of the pulse synchronization circuit used in the embodiment of FIG. 6, and FIG.
9 is a schematic diagram showing the outline of another embodiment of the present invention, and FIG. 10 is a waveform diagram showing the input/output relationship when using the pulse synchronization circuit shown in FIG. FIG. 2 is a connection diagram showing an example of a control device. 1... Leading strip material, 2... Trailing strip material, 3... Leading strip material clamping mechanism,
4, 4'... trailing strip material clamping mechanism, 5,
5', 6, 6'... Edge detection mechanism, 7... Moving frame, 8, 8'... Control device, 51a, 51b,
61a, 61b... Edge detection sensor, 55, 6
5, 55a, 55b, 65a, 65b...Sensor drive electric motor, 56, 66, 56a, 56b, 6
6a, 66b...Sensor movement amount detector, 81, 8
1'...Multiphase pulse oscillator, 82, 83...Pulse synchronization circuit, 84...Up-down counter.

Claims (1)

[Scope of Claims] 1. When joining the rear end of the leading strip material and the tip of the trailing strip material, both strip materials are clamped by two sets of clamp mechanisms, at least one of which is movable in the width direction, and the movable In a centering device that moves the clamp mechanism to align the center lines of both strips in the width direction, a pair of edge detection devices are provided for each strip to detect the edges of the strip in the width direction. a sensor, a sensor driving means for driving the edge detection sensor in the width direction of the strip material, and a movement amount detector for detecting the amount of movement of the sensor from a reference position by the sensor driving means as a number of pulses corresponding to the amount of movement. and a multiphase pulse oscillator that generates non-overlapping pulses of n phases (where n is the number of the movement amount detectors) with a cycle shorter than the minimum value of the pulse width of the output pulse of the movement amount detector; The output of the movement amount detector provided for each phase of the multiphase pulse oscillator, the output of the multiphase pulse oscillator, and the output of the edge detection sensor are input, and one pulse of the output of the movement amount detector is input. a pulse shaping circuit that generates a single pulse for each output pulse of the movement amount detector that is discriminated into two types, positive and negative; and a pulse shaping circuit that adds each output of the pulse shaping circuit according to the discrimination result. A strip comprising a single up/down counter for subtraction, and movable clamp driving means for moving the movable clamp in the width direction of the strip material by a direction and an amount determined by the counting results of the previous up/down counter. Material centering device. 2. The pulse shaping circuit includes a pulse synchronization circuit that generates a single pulse synchronized with the output of the multiphase pulse oscillator in response to one pulse of the output of the movement amount detector, and an output of the pulse synchronization circuit. and a discriminating circuit which receives as input the output of the pulse synchronization circuit and the output of the sensor and discriminates the output of the pulse synchronization circuit into an addition signal and a subtraction signal according to the order in which the outputs of the sensor are generated. Material centering device. 3. The sensor driving means is independently provided with a dedicated movement amount detector for each sensor,
The pulse shaping circuit includes a pulse synchronization circuit that converts one pulse of the output of the movement amount detector into a single pulse synchronized with the output of each phase of the multiphase pulse oscillator; 2. The strip material centering device according to claim 1, comprising a discrimination circuit that fixedly discriminates the output into an addition signal and a subtraction signal according to the corresponding movement amount detectors.