JPS5853845B2 - Length measurement control device using pulse transmitter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a length measurement control device using a pulse transmitter, particularly a pulse transmitter that measures the length of a continuously moving longitudinal material using a pulse transmitter that correlates to the rotation of a roll. relates to a length measurement control device.

FIG. 1 shows a conceptual diagram of a conventional length measurement control device of this type.

1 are rolls 21 and 2 that operate in pairs facing each other.
2. . . . Longitudinal materials 31, 32 . . . . 3n is a tip detector such as a photoelectric switch for detecting the tip of the longitudinal material 1; 41.42. ...4n is each roll 21.22. ...This is a pulse oscillator that emits a pulse signal in correlation with the rotation of 2n.

51.52. ...5n are respective corresponding tip detectors 31, 32, . ”・Signal from 3n S1.S2...S
Based on n, the corresponding pulse transmitters 41, 42°...
Input gate controlling pulse signal from 4n, 61.6
2. ...6n is the input gate 51, 52°...5
Counter 71, 7 for counting pulse signals passing through n
2. . . . In is each counter 61, 62 . . . . When 6n reaches a preset value, a match signal φ1. φ2
．． . . . A comparison circuit that outputs φn.

In operation, rolls 21, 22 degrees...
2n are all rotating at the same speed, and the detector, pulse oscillator, input gate, counter, and comparison circuit have the same configuration for each roll, so
Only the constituent elements corresponding to the first roll 21 will be described.

For example, when a longitudinal material 1 such as a pipe or a steel bar is transferred in the direction of the arrow in the figure, its tip will be detected by the tip detector 31.
This detection signal S1 is detected by the input gate 51
join.

The detection signal S1 opens the input gate 51 to allow the passage of the pulse signal P1 from the pulse transmitter 41 connected to the roll 21, and presses the counter 61 to output the pulse signal P1.
are counted.

Here, if the moving distance of the longitudinal material 1 per one pulse of the pulse signal is known in advance, the count value of the counter 61 will indicate the distance.

Therefore, by setting a target distance indicating the position of the dimension to be processed in the comparison circuit 71 in advance and pressing the button, this target distance and the contents of the counter 71 are compared, and if the contents match, a coincidence signal φ1 is output. Output.

The process of measuring the length of the longitudinal material 1 regarding the second roll 22 and the subsequent n-th rolls 2n is the same, but the target distance set in the comparison circuits 72, . , differ.

As the longitudinal material 1 is transported in the direction of the arrow in this manner, the coincidence signal φ1. φ2. ...φn is output.

In order to process the longitudinal material 1 at a desired length, this coincidence signal φ1. φ2. ...Roll 21.22. based on φn. ...2n opening/closing control button and speed control.

By the way, in the conventional length measurement control device using a pulse transmitter, as mentioned above, a tip detector is provided in front or behind each roll (in the conventional example shown in Fig. 1, at the front), and thereby the length measurement control device uses a pulse transmitter. The counter provided is incremented.

Therefore, each roll must be individually provided with a tip detector.

However, other mechanical equipment may be installed between the rolls, and in such cases, if there is no space to install a residue or tip detector, conventional length measurement control devices cannot perform length measurement. It is difficult to measure the length with high accuracy.

Therefore, the main object of the present invention is to provide a length measurement control device using a pulse oscillator that can eliminate the above-mentioned drawbacks.

To summarize, the present invention provides a length measurement control device for processing a longitudinal material at a predetermined length position between successive rolls.
A first counter that counts pulse signals from a first pulse transmitter attached to the first roll, and the contents of this 10th counter are attached to the second roll at a position where the longitudinal material has advanced a predetermined target distance. a comparator circuit that provides the timing to switch to the second pulse oscillator that is
This is a length measurement control device using a pulse transmitter that measures the length of a longitudinal material by sequentially switching the pulse transmitter attached to each roll according to the degree of penetration of the longitudinal material. be.

The above objects and features of the invention will become more apparent from the following detailed description with reference to the drawings.

FIG. 2 is a conceptual diagram showing an embodiment of the present invention.

FIG. 2 differs from FIG. 1 in the following points. That is, for example, only one tip detector 31 is provided at the front end of the first roll on the entry side of the longitudinal material.

The detection signal S1 of this tip detector 31 is transmitted to the input gate 51.
It is given as an opening/closing control signal.

tfC, input gates 51, 52, ``5n are pulse signals P1, P2 from pulse transmitters 41, 42, . . . 4n attached to each roll 21, 22, . ...Receives Pn.

These input games) 51, 52. Counters 61, 62, . . . , which individually receive the outputs of 5n. ...The output of 6n is
Corresponding comparison circuits 71, 72 . ...In, and the corresponding subtraction circuits 81 except for the final stage (nth stage)
, 82...... subtraction signal 5UB1.5UB2
.

It is given as...

Then, the outputs of each subtracting circuit 81, 82, ..., (Pl
, AP2, . . . are the counters 62 in the next stage, respectively.
．． ... is given as a preset value of 6n.

Note that the comparison circuits 71, 72 . ...7n output Φ1. Φ
2. . . . Φn is the roll 21, 22 . . . as described above.・・・
・Given as a reference signal for opening/closing control or speed control of 2n, and corresponding input game) 51.52.・・・
- It is given as an inhibit (close) signal for 5n, and also as a permit (open) signal for the input gates 52, . . . 5n in the next stage.

Furthermore, this signal φ1. φ2. . . . φn is the counter 62 of the next stage. ...Preset value JP1 to 6n
．． It also acts as a setting start signal to preset JP2...

Regarding the operation, each roll 21, 22 . ...2n are all rotating at the same speed.

When the longitudinal material 1 enters in the direction of the arrow, its tip is detected by the tip detector 31 and the input gate 51 is opened in response to a signal S1.

Then, the pulse signal P1 from the pulse transmitter 41 attached to the roll 21 passes through the input gate 51 and is input to the counter 61.

As explained in FIG. 1, if the distance traveled by the long material 1 per one pulse of the pulse signal is known in advance, the contents of the counter represent the distance, so it is set in the comparator circuit 71 in advance. By comparing the target distance moved with the contents of the counter 61, it can be determined whether the longitudinal material 1 has advanced by the target distance.

If they match, a match signal φ1 is generated.

Now, assume that the distance between the rolls 21 and 22 is L in FIG.

Then, when the tip detector 31 detects the tip of the longitudinal material 1 and the longitudinal material 1 has advanced by the distance, the tip of the longitudinal material 1 is further removed from the tip at a distance longer than the distance. It is assumed that processing will be performed.

In this case, if the longitudinal material advances by this distance, the first stage (
Transmitter 41, input gate 51, counter 61. ...)
to the second stage (oscillator 42, input gate 52, counter 62, . . . ).

Therefore, the distance is set in the comparison circuit 71 in advance.

Now, when the contents of the counter 61 are equal to, less than, or more than L, a switching signal (also a coincidence signal) φ1 is output.

This signal φ1 closes the input gate 51 of the first counter 61, simultaneously becomes an open signal for the second input gate 52, and becomes a preset signal for the 20th counter 62.

Therefore, when the signal Φ1 is obtained, the result of the calculation (content of the counter 61) -L, ie, JP1, calculated by the first subtraction circuit 81 is preset loaded as the initial value of the counter 62.

Since the second stage input gate 52 is opened by the signal φ1, the counter 62 increments from the preset initial value JPI by the pulse signal P2 from the second pulse oscillator 42.

Below are the 2nd and 3rd rows, the 3rd and 4th rows, etc.
The operation mode is the same.

In the above embodiment, only L is shown as the value to be compared with the contents of the first counter, but if there are other comparison values having values less than or equal to L, a similar comparison circuit can be connected in parallel to the comparison circuit 7. may be added to.

In this way, a plurality of matching signals can be derived and finer binary signals can be obtained between the rolls, which has the advantage of providing more accurate length measurement results and more preferable control.

If the distance traveled by the longitudinal material per pulse changes depending on the shape of the roll, the size of the longitudinal material, etc., a correction circuit may be configured in conjunction with the comparison circuit.

This also has the advantage of increasing the versatility of this length measuring device.

Furthermore, if the length measurement accuracy is such that it is not necessary to switch the pulse transmitter for each roll, there is no need to provide a pulse transmitter for each roll, for example, for every 2 or 3 rolls. It is only necessary to provide one pulse generator per machine.

This has the advantage of simplifying equipment and reducing costs.

As described above, according to the present invention, only one tip detector is provided corresponding to a specific roll on the entrance side of the longitudinal material, and from then on, specific settings are determined by the comparison circuit on the length measurement control device side. Since the pulse transmitter is configured to switch sequentially based on the value, firstly, the number of detectors can be reduced, and secondly, the detector can be installed between rolls, which solves the problem of space. There is no need to consider it anymore.

Further, pulse count errors during the counter switching period can also be corrected by providing a subtraction circuit, so length measurement errors can be made extremely small.

In addition, each comparison circuit button and each subtraction circuit are integrated (second
(The part surrounded by the two-dot chain line in the figure) If the programmable controller is used as a single device, the length measurement control device itself will have a simple configuration, and the length measurement and control can be performed with more precision, and the length measurement control is more advantageous. A device is obtained.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram showing a length-measuring device for longitudinal materials using a conventional pulse transmitter. FIG. 2 is a conceptual diagram showing an embodiment of the present invention. In the figures, the same reference numerals indicate the same or corresponding parts, 1 is a longitudinal material, 21.22, . . . 2n are rolls, 31, 32, . ...3n is the tip detector, 41.42
．． ...4n is a pulse transmitter, 51.52°...5n
is an entry card game), 61, 62. ...6n is a counter, γ
1,72. ...7n is a comparison circuit, 81°82, ...
indicate subtraction circuits, respectively.

Claims (1)

[Scope of Claims] 1. A length measurement control device using a pulse transmitter that measures the length of a moving longitudinal material using a pulse transmitter that correlates to the rotation of a roll, comprising: a plurality of rollers arranged at predetermined intervals on the transfer path; a detector provided at any position on the transfer path where the plurality of rollers are arranged to detect the tip of the longitudinal material to be transferred; a plurality of pulse transmitters that are provided corresponding to each of the rollers and generate pulse signals in accordance with the rotation of each roller; a plurality of counters that individually receive pulse signals from each of the plurality of pulse transmitters; A plurality of comparison circuits and buttons that compare the counted value of each counter with a preset set value, and output an output when the counted value of the counter matches the set value or exceeds the set value. and a subtraction circuit that subtracts a set value preset in the comparator circuit from the counted value of the counter, and the detection output of the detector is given as a counting start signal to a predetermined tenth counter among the plurality of counters. , Output of the comparison circuit corresponding to the tenth counter among the plurality of comparison circuits causes the first counter to stop counting, and a predetermined second counter among the plurality of counters to start counting. The subtraction value of the subtraction circuit corresponding to the first counter among the plurality of subtraction circuits is set as the initial value of the 20th counter by the switching signal. Multiple counter comparison rotations,
1. A length measurement control device using a pulse oscillator, characterized in that the subtraction circuit is sequentially switched and operated. 2. The length measurement control device using a pulse oscillator according to claim 1, wherein each of the comparison circuits and each of the subtraction circuits are included in a programmable controller.