JP2712973B2 - Ultrasonic thread length meter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a yarn length meter for measuring the length of a yarn when the yarn is unwound or wound up from a yarn winding, and more particularly to measuring the length of the yarn using an ultrasonic distance meter. The present invention relates to an ultrasonic yarn length meter.

[0002]

2. Description of the Related Art As a yarn length meter for measuring the length of a yarn unwound or wound from a bobbin, for example,
As shown in FIG. 3, an ultrasonic microphone 53 which is a part of the ultrasonic distance meter 52 is disposed at a position facing the surface of the spool 51 around which the yarn 57 is wound, and the spool detected by the ultrasonic distance meter 52 is also provided. A radius calculating means 54 for calculating a radius r of the bobbin 51 from a distance D between the ultrasonic microphone 53 and
Further, a tachometer 55 for detecting the number of rotations of the bobbin 51, a yarn length calculating means for calculating a yarn length from rotation data detected by the tachometer 55 and a radius r of the bobbin 51 calculated by the radius calculating means. (Integral calculation means in this conventional example) 5
6 is provided with an ultrasonic thread length meter.

In this conventional ultrasonic thread length meter, an ultrasonic distance meter 52 detects the distance D between the bobbin 51 and the ultrasonic microphone 53 at regular time intervals, and a radius calculating means 54 calculates the distance D from the distance D. The radius r of the bobbin 51 is calculated, and the integral calculating means 56 outputs the bobbin 51 from the radius r of the bobbin 51 obtained by the radius calculating means 54 and the number of rotations (the amount of rotation) detected by the tachometer 55. The length of the thread 57 is calculated.

[0004]

However, in the above-described ultrasonic thread length meter, while the ultrasonic thread length meter is in use, the power of the ultrasonic distance meter is always on and the distance is detected (measured). ) Is performed at regular time intervals, the power consumption is large, and when a battery is used as a power source, the battery runs out in a short time, and there is a problem that it takes time to replace the battery. There is a problem that the thread length cannot be measured in a situation where the battery cannot be replaced on the way.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide an ultrasonic thread length meter having low power consumption and a long battery life.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an ultrasonic thread length meter according to the present invention comprises an ultrasonic distance meter for detecting a thread, a distance to a surface of the thread, and a rotation number of the thread. Tachometer, a radius calculating means for calculating the radius of the bobbin from the distance data detected by the ultrasonic distance meter, and a yarn based on the number of rotations of the bobbin detected by the tachometer and the radius of the bobbin calculated by the radius calculating means. And a thread length calculating means for calculating the length of the bobbin, the ultrasonic rangefinder performs distance detection only when the tachometer detects rotation of the bobbin, and the rotational speed of the bobbin is high. sometimes distance interval of the detection is shortened, to switch the time interval of the distance detection as ultrasonic distance meter spacing distance detection becomes long in accordance with the rotational speed of the yarn detected by tachometer when the rotational speed of the yarn is small It is with the features.

Further, a switch means for turning off the power of the ultrasonic range finder when the tachometer does not detect the rotation of the bobbin can be added to the ultrasonic thread length meter.

[0008]

In the ultrasonic thread length meter according to the present invention, the ultrasonic distance meter operates only when the tachometer detects the rotation of the bobbin, and the distance is detected. When the rotational speed of the bobbin is high, the distance is detected. interval is shortened, and so that the distance of the distance detection becomes longer when the rotational speed of the yarn is small super
The time interval of the distance detection of the ultrasonic rangefinder is switched according to the rotational speed of the bobbin detected by the tachometer. Instead, it is possible to perform more efficient distance detection than when distance detection is always performed at a constant time interval, and power consumption can be reliably reduced.

Further, by adding a switch means for turning off the power of the ultrasonic distance meter when the rotation meter does not detect the rotation of the bobbin, the ultrasonic distance when the rotation of the bobbin is stopped is added. By setting the power consumption in the meter to 0, the power consumption of the entire ultrasonic yarn length meter can be further reduced.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an ultrasonic yarn length meter according to the present invention. FIG. 1 is a schematic diagram showing a basic configuration of an ultrasonic yarn length meter according to one embodiment of the present invention. As shown in FIG. 1, the ultrasonic thread length meter of this embodiment has an ultrasonic wave provided with an ultrasonic microphone 3 for measuring a distance D between the thread 1 and a thread 1 around which a thread 7 is wound. Distance meter 2 and pin 1
And a tachometer 5 for detecting the number of rotations (the amount of rotation). The ultrasonic range finder 2 is connected to the tachometer 5, and performs distance detection only when the tachometer 5 detects the rotation of the peg 1, as described later.
The time interval of the distance detection of the ultrasonic distance meter 2 is detected by the tachometer 5 so that the interval of the distance detection becomes shorter when the rotation speed of the spool 1 is high, and the interval of the distance detection becomes longer when the rotation speed of the bobbin 1 is low. It is configured to switch in accordance with the rotation speed of the wound spool 1 . Further, the ultrasonic thread length meter includes a radius calculating means 4 for calculating a radius r of the peg 1 from the distance data, a rotation data detected by the tachometer 5 and a radius r of the peg 1 calculated by the radius calculating means 4. And a yarn length calculating means (in this embodiment, an integral calculating means) 6 for calculating a yarn length from the yarn.

FIG. 2 is a diagram showing a more specific configuration of the ultrasonic yarn length meter of the above embodiment. As shown in FIG. 2, in the ultrasonic thread length meter, magnetic switches 11a, 1 constituting a tachometer 5 at a predetermined position near the bobbin 1.
1b and 11c are provided. A magnet 12 is attached to the peg 1, and the peg 1 rotates and the magnet 12 attached to the peg 1 is connected to the magnetic switches 11a, 11b, 11
When the value approaches c, the magnetic switches 11a, 11b, 11c are sequentially turned on, and the tachometer 5 detects this, and outputs the number of rotations (the amount of rotation) in the form of an electric signal.

The ultrasonic distance meter 2 includes an oscillator 21 that periodically outputs a voltage, an oscillator 22 that oscillates an ultrasonic wave only while a voltage is being output from the oscillator 21, and a transmission amplifier 2.
3, transmitting microphone 24, receiving microphone 25, receiving amplifier 2
6, detector 27, differentiator 28, comparator 29, flip-flop circuit 30, AND circuit 31, counter 3
2, a distance calculation unit 33.

In this ultrasonic rangefinder 2, an oscillator 2
1 periodically outputs a voltage, and the oscillator 22
Oscillates at the transmission frequency of the ultrasonic wave only while the voltage is being output. Then, this is amplified and input to the transmission microphone 24, and the transmission microphone 24 emits an ultrasonic wave. The ultrasonic waves emitted from the transmitting microphone 24 are reflected on the surface of the wound pin and reach the receiving microphone 25. The signal output from the receiving microphone 25 is amplified by the receiving amplifier 26 and detected by the detector 27. After the detection waveform is further differentiated by a differentiator 28, it is compared with a reference voltage by a comparator 29. The comparator 29 outputs a voltage only when the input becomes higher than the reference voltage. Therefore, the time during which the comparator 29 is outputting a voltage is the time during which the ultrasonic wave is being received, and the time from when the oscillator 21 outputs the voltage until the comparator 29 outputs the voltage is the reflection time of the ultrasonic wave. Become.

The flip-flop circuit 30 detects the reflection time, and the AND circuit 31 calculates the product of the reflection time and a clock signal of a constant frequency, thereby obtaining a pulse corresponding to the reflection time. By counting the number of pulses by the counter 32, the number of pulses proportional to the reflection time can be obtained. Further, since the reflection time is proportional to the distance, the distance calculation unit 3
In step 3, the number of pulses is converted into a distance, and the result is output to the radius calculating means 4.

The radius r of the bobbin 1 calculated by the radius calculating means 4 and the number of rotations (the amount of rotation) of the bobbin 1 detected by the tachometer 5 are input to a yarn length calculating means (integral calculating means) 6, The yarn length calculating means (integral calculating means) 6 calculates the yarn length from the radius r of the bobbin 1 and its rotation speed.

In the above ultrasonic thread length meter, when the bobbin 1 rotates and the magnet 12 attached to the bobbin 1 approaches one of the magnetic switches 11a, 11b and 11c and one magnetic switch is turned on, The oscillator 21 is configured to output a pulse, and performs distance detection (measurement) only at that time. Accordingly, the distance detection is performed by the number of magnetic switches (three times in this embodiment) during one rotation of the bobbin. When the rotational speed of the bobbin 1 is high, the rotational speed of the bobbin 1 is reduced at short time intervals. Is small,
Distance detection is performed at long time intervals and the tachometer 5
Since the distance detection is not performed when the rotation of the bobbin 1 is not detected, efficient distance detection can be performed, the power consumption can be reduced, and the battery life can be improved.

Further, a switch (not shown) such as a transistor or an FET is inserted into a power supply line of the ultrasonic range finder 2 so that power supplied to the ultrasonic range finder 2 can be cut by an external signal. When distance detection is not performed for a certain period of time (that is, when the bobbin 1 is not rotating), the power of the ultrasonic range finder can be turned off. The power consumption of the entire length meter can be further reduced.

The method of detecting the rotation of the bobbin is not limited to the method of the above-described embodiment using a magnetic switch, but the rotation of the bobbin is transmitted to another portion by a gear belt or the like, where the bobbin rotation is detected. The rotation may be detected.

Further, in the distance detection, the magnetic switch is turned on.
May be performed a plurality of times in succession.

[0020]

As described above, in the ultrasonic thread length meter according to the present invention, the ultrasonic distance meter detects the distance only when the tachometer detects the rotation of the bobbin, and according to the rotational speed of the bobbin. Because it is configured to switch the time interval of distance detection, compared to the case where distance detection is always performed at a fixed time interval regardless of the state of thread take-out or thread winding, as with the conventional ultrasonic thread length meter. It is possible to perform efficient distance detection, reduce power consumption when the rotation speed of the bobbin is low or when the bobbin is not rotating, reduce power consumption, and use a battery as a power supply. Battery life can be improved.

Further, by adding a switch means for turning off the power of the ultrasonic distance meter when the rotation meter does not detect the rotation of the bobbin, the ultrasonic distance when the rotation of the bobbin is stopped is added. By setting the power consumption in the meter to 0, the power consumption of the entire ultrasonic yarn length meter can be further reduced.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the configuration of an ultrasonic yarn length meter according to the present invention.

FIG. 2 is a diagram showing a configuration of an ultrasonic yarn length meter according to one embodiment of the present invention.

FIG. 3 is a schematic diagram showing a configuration of a conventional ultrasonic yarn length meter.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Pincushion 2 Ultrasonic distance meter 3 Ultrasonic microphone 4 Radius calculation means 5 Tachometer 6 Thread length calculation means (integration calculation means) 7 Thread 11a, 11b, 11c Magnetic switch

Claims (2)

(57) [Claims] 1. An ultrasonic range finder for detecting a bobbin, a distance to a bobbin surface, a tachometer for detecting the number of revolutions of the bobbin, and a radius of the bobbin based on distance data detected by the ultrasonic range finder. An ultrasonic thread length meter comprising: a radius calculating means; and a yarn length calculating means for calculating a length of the yarn from a rotation number of the bobbin detected by the tachometer and a radius of the bobbin calculated by the radius calculating means. The ultrasonic rangefinder performs distance detection only when the bobbin rotation is detected, and the distance detection interval is short when the bobbin rotation speed is high, and the distance detection interval is long when the bobbin rotation speed is low. so as to the time interval of the distance detection of the ultrasonic distance meter times
An ultrasonic thread length meter characterized in that switching is performed in accordance with the rotation speed of a bobbin detected by a transmeter. 2. The ultrasonic thread length meter according to claim 1, further comprising switch means for turning off the power of the ultrasonic distance meter when the rotation meter does not detect the rotation of the bobbin.