JP2000221069A - Flow rate detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To unnecessitate electric power consumption of a battery-driven flow rate detection circuit. SOLUTION: This flow rate detection device has magnets 1 each passing a fixed position whenever a unit flow quantity is measured, a flow rate sensor 3 outputting a voltage generated in a coil as a flow rate signal whenever the flow rate sensor 3 faces the magnet 1 to allow reversal of a magnetic field within an iron core having a large Barkhausen effect, and a battery 6 that is a controlling power supply for the flow rate detection device. Since the output voltage of the flow rate sensor 3 is used as the signal, the flow rate sensor 3 requires no power supply.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow detecting device such as a gas meter.

[0002]

2. Description of the Related Art A conventional flow detecting device of this type will be described with reference to FIGS. 1 is a gas meter main body, 2 is a gas inlet, 3 is a gas outlet, and 4 is a mechanical integrated value display section for displaying a flow rate of gas passing through the gas meter. As shown in FIG. 6, the gas meter 1 is a reed switch provided to face a passing position of a permanent magnet 6 attached to a rotating body 5 which rotates in conjunction with a film-type measuring unit (not shown) for measuring a passing flow rate. The on / off operation of 7 is converted into an electric signal by the flow rate detection circuit 8. The flow detection circuit 8 outputs a flow signal voltage obtained by dividing the voltage of the battery 13 by the resistors 8a and 8b. Reference numeral 9 denotes a flow rate measuring unit for measuring an on / off flow rate signal from the flow rate detecting circuit 8, which is constituted by a microcomputer or the like. Flow measurement unit 9
Is configured to monitor a gas flow rate value, leakage, etc., shut off the valve 11 via a valve drive unit when an abnormality occurs, and issue an alarm on the display unit 12, and these power supplies are supplied from the battery 13. It has become.

[0003]

However, in the conventional flow rate detecting device, the reed switch is turned on / off by the magnetic field of the permanent magnet. Therefore, the permanent magnet attached to the rotating body which rotates in conjunction with the unit measurement is used. When stopped in the on-field of the reed switch, the flow detection circuit has a problem that current continues to flow through the voltage-dividing resistor, thereby increasing unnecessary power consumption and shortening the battery life.

Further, since the reed switch is a mechanical contact, the contact turns on and off due to vibration and impact, and the flow rate measurement is erroneously detected. In addition, the on / off impression value shifts due to a change in the contact interval of the reed switch. And the flow rate cannot be detected.

[0005]

In order to solve the above-mentioned problem, the present invention faces a magnet passing through a fixed position every time a unit flow rate is measured, and sets a coil every time a magnetic field in a core having a large Barkhausen effect is reversed. And a flow rate sensor for outputting a voltage generated in the flow rate sensor, and a flow rate measuring means that uses the output voltage of the flow rate sensor as a signal.

[0006] According to the above, the flow rate sensor can be made without a power source for detecting the voltage generated by reversing the magnetic field of the magnet passing through the fixed position every unit flow rate measurement.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention comprises a magnet passing a fixed position for each unit flow measurement, a flow sensor provided facing the magnet, and a flow measuring means for measuring an output signal of the flow sensor. The flow sensor uses a voltage induced every time the polarity of a passing magnet is reversed as a flow signal. Further, since the voltage generated in the flow sensor is used as the flow signal, unnecessary current of the flow detection circuit including the flow sensor can be eliminated.

The flow sensor has a configuration in which a voltage generated in the coil is output each time the magnetic field in the iron core having the large Barkhausen effect is reversed. Since the voltage is output only when the applied magnetic field of the flow sensor is reversed, erroneous output due to vibration or impact can be eliminated.

Further, by increasing the number of poles of the magnet passing each time the unit flow rate is measured, the resolution of the unit measurement can be increased with one flow sensor.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a configuration diagram of a gas meter flow rate detecting device according to Embodiment 1 of the present invention. FIG. 2 is a structural diagram of the flow sensor, and FIG. 3 is an operation principle diagram of the flow sensor.

In FIG. 1, reference numeral 1 denotes a permanent magnet attached to a rotating body 2 which rotates in conjunction with a film-type measuring unit (not shown) for measuring a passing flow rate. Place at 180 °. Reference numeral 3 denotes a flow sensor provided facing the passage position of the permanent magnet 1, and outputs a pulse voltage every time the polarity of the permanent magnet 1 is inverted from the N pole to the S pole and from the S pole to the N pole. Reference numeral 4 denotes a signal processing circuit for waveform-processing a pulse voltage output from the flow sensor 3, and reference numeral 5 denotes a flow rate measuring means for measuring a flow signal from the signal processing circuit, which is constituted by a microcomputer or the like. Reference numeral 6 denotes a battery serving as a control power supply for the flow rate measuring means 5 and the like.

Next, the operation and operation will be described. The flow sensor has a structure as shown in FIG. 2, and reference numeral 3a denotes an iron core having a large Barkhausen effect, around which a detection coil 3b is wound. As an iron core having a large Barkhausen effect, an iron element in which an amorphous element is formed in a fiber shape is disclosed. When the polarity of the applied magnetic field in the direction shown in the figure is reversed, positive and negative pulse voltages are induced in the detection coil 3b according to a sudden magnetic flux change.

The pulse voltage is synchronized with the polarity of the magnet 1 passing through the flow rate sensor 3 as shown in FIG. 3, and the signal processing circuit 4 may be configured to detect, for example, a positive pulse voltage when the N pole is inverted. When the membrane type measuring section makes one rotation, the flow rate measuring means 5 can recognize it as a unit measured flow rate. It should be noted that a single permanent magnet magnetized with N polarity and S polarity can be similarly implemented.

(Embodiment 2) FIG. 4 is a structural view of a permanent magnet of a gas meter flow rate detecting device according to the present invention. The difference from the first embodiment is that permanent magnets are arranged at 90 ° intervals on the north pole and the south pole for one flow sensor.

The components having the same reference numerals as in the first embodiment have the same structure, and the description is omitted.

Next, the operation and the operation will be described. Since the pulse voltage can be obtained twice from the flow rate sensor 3 with respect to one rotation unit measurement flow rate of the membrane type measuring unit, the unit resolution of the flow rate measurement can be increased. Can be. That is, the flow rate measuring means 5 can capture a minute change in the flow rate, thereby increasing the leak detection accuracy.

[0018]

As described above, according to the present invention, the voltage generated in the coil every time the magnetic field in the iron core having the large Barkhausen effect is reversed, facing the magnet passing through the fixed position every unit flow rate measurement. Since the output voltage of the output flow sensor is used as the flow signal, the flow sensor circuit has an advantageous effect that it can be configured without a power supply.

Further, since there is no mechanical structure, malfunction due to vibration or impact can be eliminated, and the accuracy of flow rate detection and the reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a flow rate detection device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a flow sensor of the apparatus.

FIG. 3 is a diagram illustrating a flow signal of the apparatus.

FIG. 4 is a diagram showing a relationship between a magnet and a flow sensor in a flow detection device according to a second embodiment of the present invention.

FIG. 5 is an external perspective view of a gas meter.

FIG. 6 is a configuration diagram of a conventional gas meter flow rate detection device.

[Explanation of symbols]

 Reference Signs List 1 magnet 3 flow sensor 5 flow measuring means 4 battery

Claims (3)

[Claims] 1. A magnet passing a fixed position for each unit flow rate measurement, a flow sensor provided facing the magnet, a flow rate measuring means for measuring an output signal of the flow rate sensor, and a control power supply for the flow rate measuring means. Wherein the flow sensor uses a voltage generated in the coil as a flow signal every time the magnetic field in the iron core having the large Barkhausen effect is reversed. 2. A flow rate detecting device according to claim 1, wherein one magnet is magnetized with N polarity and S polarity, and a magnetic field is changed for each unit measurement to the flow rate sensor. 3. A flow rate detecting apparatus comprising a single flow rate sensor and a plurality of magnets to increase the number of magnetic field changes per unit flow rate measurement.