KR20090093328A - Measuring instrument - Google Patents

Abstract

A meter using a rotation sensor utilizing the property of an LC resonance circuit is provided to prevent the metric performance from lowering even if it uses the long time. A meter comprises a body(20), a rotational plate(37), a first and second rotation sensor(43), a power source, a controller, a display part. The rotational plate is pivotally installed inside the body. The rotational plate is connected to the rotator. The rotational plate comprises a conductor part and a nonconductor part. The rotating sensor includes an inductor(44) and a capacitor(45). The rotating sensor detects the rotation of a rotor by damping the voltage waveform generated in the conductor part when contacting the inductor with the conductor part. The inductor is installed inside the body in order to face with the one side of the rotational plate. The capacitor is connected to the inductor and an LC resonance circuit. The controller receives a sensing signal from the rotation sensor to output the rotation number of the rotor.

Description

Meter {MEASURING INSTRUMENT}

The present invention relates to a meter, and more particularly, to an improved meter to accurately and stably measure water, gas, electricity, and the like by using a rotation sensor that can detect rotation of a rotating plate.

On the supply line for supplying water, gas, electricity, etc. used for domestic and industrial purposes, a meter for measuring the amount used is installed. The meter usually takes the form of an integrated meter in which the amounts used are accumulated or summed and the amount is visually displayed. Such a meter generally detects the number of revolutions of the rotating body that is rotated as a constant, gas, electricity, etc. is supplied, and calculates the supply amount according to the revolutions.

The meter that calculates the amount of use by the number of revolutions of the rotating body can be largely divided into a mechanical meter and an electronic meter. The mechanical meter has a gear set that cooperates with the rotating body and a counter set that includes a numeric dial or instructions that cooperate with the gear train. On the other hand, the electronic meter has a sensor that can detect the rotation of the rotating body.

Nowadays, AMR (Automatic Meter Reading) system that can collect usage information from a remote site without checking the meter reading by the meter reader directly, the electronic meter is preferred to the mechanical meter.

As a sensor used in an electronic meter, a magnetic sensor using a magnet and an optical sensor are well known. The magnetic sensor detects the rotational speed of the rotating body by using the change of the magnetic field of the magnet attached to the rotating body, and the optical sensor detects the rotational speed of the rotating body by using the change in the amount of light emitted to the rotating body.

However, the magnetic sensor is affected by an external magnetic field, and iron is easily attached to the magnet, which causes a problem in that rotation of the rotating body is easily affected by external factors. In addition, the optical sensor consumes a high current and has a complicated design for the rotating body.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to accurately detect rotation of a rotating body according to supply of constant, gas, electricity, etc., and to provide a meter operated at low power.

Meter according to the present invention for achieving the above object is a body rotatably installed therein; A rotating plate rotatably installed in the body to interlock with the rotating body and having a conductor portion and a non-conductive portion; A rotation sensing sensor having an inductor installed in the body to face one surface of the rotating plate and a capacitor connected to the inductor to form an LC resonance circuit together with the inductor; A power supply for supplying a voltage to the rotation sensor; A control unit which receives the detection signal from the rotation detection sensor and calculates the rotation speed of the rotating body; And a display device controlled by the control unit to display information, wherein the rotation sensor is configured such that the voltage waveform is attenuated by an eddy current generated in the conductor portion when the inductor faces the conductor portion. It is characterized by detecting the rotation of the.

The body has a first housing having a flow path in which the rotating body is located, a second housing coupled to the first housing and having a rotation board, a circuit board having the control unit, and an installation space for accommodating the display device. And a separating member made of a non-conductive material disposed between the first housing and the second housing to separate the flow path and the installation space, and the rotating plate may be coupled to the rotating body.

The rotation sensor may be one in which the inductor and the capacitor are connected in parallel.

In addition, a plurality of the rotation detection sensor may be installed.

In addition, the rotating plate may have a structure in which a conductive plate is coupled to one surface of the non-conductive plate.

The meter according to the present invention can accurately detect the rotation of the rotating body at low power by using a rotation sensor using the characteristics of the LC resonance circuit. Therefore, it is possible to accurately measure the amount of use of water, gas, electricity and the like, and the metering performance does not deteriorate even when used for a long time.

1 is a side cross-sectional view schematically showing a meter according to an exemplary embodiment of the present invention.

2 is a block diagram showing a part of the configuration of the meter according to an exemplary embodiment of the present invention.

3 is a circuit diagram of a rotation sensor of a meter according to an exemplary embodiment of the present invention.

4A and 4B are perspective views for explaining the operation of the rotating plate and the rotation sensor of the meter according to an exemplary embodiment of the present invention.

5A and 5B show voltage waveforms of a rotation sensor of a meter according to an exemplary embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

10.Weighing machine 20 ... Body

21, 22 ... 1st and 2nd housing 23 ... Euro

27.Installation space 29 ... Separation member

31,32 Sealing element 33 Impeller

34 ... support shaft 35 ... rotation shaft

37.Turning plate 38 ... Conductor part

39, non-conducting part 43, 46 ... 1,2 rotation detection sensor

44,47 ... inductor 45 ... capacitor

51 ... circuit board 52 ... control unit

53 ... LCD 54 ... Power

Hereinafter, a meter according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

1 is a side cross-sectional view schematically showing a water meter as a meter according to an exemplary embodiment of the present invention.

As shown in FIG. 1, the meter 10 according to an exemplary embodiment of the present invention includes a body 20, an impeller 33 and a rotating plate 37 rotatably installed inside the body 20, and First and second rotational sensors 43 and 46 for detecting rotation of the impeller 33 and circuit boards 51 equipped with various circuits and electric elements for controlling the overall operation of the meter 10. It includes.

The body 20 is connected to a water supply pipe (not shown), and includes a first housing 21 having a flow path 23, a second housing 22 coupled to an upper portion of the first housing 21, and a first It consists of a separating member 29 for separating the inside of the housing 21 and the inside of the second housing (22).

The first housing 21 has a flow path 23 through which the constant flows, and first and second connections 24 and 25 connected to the water supply pipe, respectively. The first connection part 24 is equipped with a filter 26 for filtering foreign matter, and the constant flows through the flow path 23 from the first connection part 24 to the second connection part 25. The opening 21a is formed in the center upper surface of the 1st housing 21, and the separating member 29 is provided in this opening 21a. Separation member 29 is a non-conductor such as plastic so as not to interfere with the electromagnetic interaction between the rotating plate 37 is installed on the lower portion and the first and second rotation sensor 43, 46 installed on the top It is made of material. In the center of the lower surface of the separating member 29, a bearing 36 for rotatably supporting the rotating shaft 35 to be described later is installed. The sealing member 31 is installed at the edge of the separating member 29, and the sealing member 31 seals a gap between the first housing 21 and the separating member 29. Therefore, the opening 21a of the first housing 21 is completely sealed by the separating member 29 and the sealing member 31.

The second housing 22 has an installation space 27 for accommodating components such as the first and second rotation detection sensors 43 and 46 and the circuit board 51. The upper surface of the second housing 22 is provided with a transparent window 28 to externally check the LCD 53 mounted on the circuit board 51. An opening 22a is formed at one side of the second housing 22, and a power supply line 55 connected to the circuit board 51 through the opening 22a is exposed to the outside of the second housing 22. do. A sealing member 32 for sealing a gap between the power supply line 55 and the second housing 22 is inserted into the opening 22a.

The circuit board 51 is fixedly installed in the installation space 27. The circuit board 51 includes a controller 52, a memory (not shown), a circuit such as a pulse voltage supply unit (not shown), and an electronic device. As shown in FIG. 2, the control unit 52 receives a voltage from the power supply 54, receives detection signals of the first and second rotation detection sensors 43 and 46, and controls the LCD 53. To display information such as cumulative usage. The LCD 53 may be replaced by another display device capable of displaying information.

The impeller 33 is rotatably installed in the flow path 23 of the first housing 21. The impeller 33 has a boss portion 33a rotatably supported by a support shaft 34 fixed to one inner side of the first housing 21. In the center of the boss portion 33a, a rotating shaft 35 rotatably coupled to the bearing 36 is coupled to have the same center of rotation as the support shaft 34. The impeller 33 rotates by a constant flowing through the flow path 23. In the present invention, the impeller 33 may be replaced by another rotating body rotated by a constant flowing through the flow path 23. The rotating plate 37 is fixed to the upper surface of the boss portion 33a and rotates together with the impeller 33.

The rotating plate 37 has a donut shape with an opening 37a in which a bearing 36 is inserted in the center, and is composed of a conductor portion 37 in which an eddy current is generated, and a non-conductive portion 38 in which an eddy current is not generated. . As shown in FIG. 4A, the rotating plate 37 has a structure in which a semicircular conductor plate 41 having a center cut out is coupled to an upper surface of the donut-shaped non-conductor plate 42. The conductor portion 38 occupies half of the upper surface of the rotating plate 37, and the non-conductive portion 39 occupies the other half of the rotating plate 37. Of course, it is possible to have a structure in which the area of either the conductor portion 37 or the non-conductor portion 38 is larger and the area of the others is smaller.

A nonmagnetic metal such as copper or aluminum may be used as the material of the conductive plate 41, and plastic may be used as the material of the non-conductive plate 42. Of course, the conductive plate 41 may be made of a nonmagnetic metal other than copper or aluminum, and the non-conductive plate 42 may be made of a non-conductive material other than plastic. In the present invention, since the conductive plate 37 and the non-conductive unit 38 need only exist on the upper surface of the rotating plate 37 that faces the first and second rotation detecting sensors 43 and 46, the rotating plate 37 is The semicircular conductor plate and the semicircular non-conductor plate may be formed in a structure in which they are bonded to each other. Of course, the shape of the rotating plate 37 is not limited to a circular shape can be variously changed.

The first and second rotation detection sensors 43 and 46 detect the rotation of the rotary plate 37 by using characteristics of the LC resonance circuit, and are respectively provided with inductors 44 facing the upper surface of the rotary plate 37. And a capacitor 45 (not shown) connected to each inductor 44 and 47. As shown in FIG. 3, each rotation detecting sensor 43, 46 is connected to each inductor 44, 47 and each capacitor 45 in parallel to form an LC parallel resonance circuit, and a power supply 54. The voltage is supplied from Each inductor 44, 47 is coupled to an inductor support member 48 fixedly installed in the installation space 27, and each capacitor 45 is fixed to the circuit board 51. Of course, the installation positions of each inductor 44 and 47 and each capacitor 45 may be variously changed. The operating principle of each rotation sensor 43, 46 is as follows. Since the principle of operation of the first rotation sensor 43 and the second rotation sensor 46 is the same, the first rotation sensor 43 will be described below.

When a pulse voltage is supplied to the first rotation detection sensor 43, energy is charged in the inductor 44 and the capacitor 45. In the case of the ideal inductor 44 and the capacitor 45, this energy is always resonated in a constant form, and the resonant frequency at this time is expressed by the following equation.

In general, since the inductor 44 has a resistance, the waveform of the LC resonant circuit gradually decreases with time. At this time, when the conductor portion 37 is placed below the inductor 44, the magnetic field generated by the inductor 44 generates an eddy current in the conductor portion 37. This eddy current creates a new magnetic field that changes the mutual inductance of the inductor 44. Therefore, the resonance frequency is changed and the voltage waveform of the LC resonant circuit is rapidly attenuated. That is, when the conductor portion 37 is adjacent to the resonant LC resonant circuit, it becomes a form of an electrical load, and the voltage waveform is rapidly attenuated.

As shown in FIG. 4A, when the rotating plate 37 rotates so that the inductor 44 of the first rotational sensor 43 faces the conductor portion 37, an eddy current is generated in the conductor portion 37 so that the first The voltage waveform of the rotation detection sensor 43 is rapidly attenuated as shown in Fig. 5A. On the contrary, when the rotating plate 37 rotates as shown in FIG. 4B and the inductor 44 of the first rotation detecting sensor 43 faces the non-conducting portion, no eddy current is generated in the non-conducting portion 38. The voltage waveform of the first rotation sensor 43 is attenuated slowly as shown in FIG. 5B.

Therefore, after a predetermined time t _delay , the magnitude of the voltage waveform is compared with the reference value V _ref , and if there is no signal larger than the reference value V _ref , the inductor 44 faces the conductor portion 37. If there is a signal larger than the reference value V _ref , it can be seen that the inductor 44 faces the non-conducting portion 38. Through the change characteristic of the voltage waveform, the first rotation sensor 43 may detect rotation of the rotating plate 37 and the impeller 33.

 In the LC resonant circuit, the attenuation of the voltage waveform depends on factors such as the relative position of the inductor and the conductor, the distance between the inductor and the conductor, the size and thickness of the conductor, and the magnetic permeability of the conductor. Therefore, in the design of the first and second rotation detection sensors 43, 46, the relative positions of each inductor 44, 47 and the conductor portion 37, each inductor 44, 47 and the conductor portion ( Each rotation detecting sensor 43, 46 capable of accurately detecting the rotation of the rotating plate 37 by appropriately selecting the distance between the 37, the size and thickness of the conductor portion 37, and the permeability of the conductor portion 37. Can be implemented. The number of rotation detection sensors may vary. The rotation of the rotary plate 37 may be detected by one rotation sensor, but the number of the rotation sensors may be plural in consideration of a failure.

Hereinafter, with reference to the accompanying drawings will be described the operation of the meter 10 according to an exemplary embodiment of the present invention.

As shown in FIG. 1, when a constant flows through the flow path 23 of the body 20, the impeller 33 rotates. At this time, the rotary plate 37 coupled to the impeller 33 rotates like the impeller 33. When the rotating plate 37 rotates so that the positions of the conductor portion 37 and the non-conductor portion 38 are changed, the voltage waveforms of the first and second rotation detection sensors 43 and 46 are changed from the pattern of FIG. 5A to the pattern of FIG. 5B. , The pattern of FIG. 5B is changed from the pattern of FIG. 5A. The pattern change of the voltage waveform is transmitted to the controller 52 as a detection signal. At this time, the control unit 52 calculates the cumulative usage amount of the rotation speed and the constant of the impeller 33 through the detection signals of the first and second rotation detection sensors 43 and 46, and calculates the accumulated cumulative usage amount of the LCD 53. ).

As such, the meter 10 according to the present invention can accurately detect the rotation of the rotary plate 37 at low power by using the rotation detection sensors 43 and 46 using the characteristics of the LC resonance circuit. Therefore, the constant amount of water used can be accurately measured, and the weighing performance is not degraded even when used for a long time.

In the above, the meter according to the present invention has been described with an example of a water meter, but the meter according to the present invention may be applied to various meters such as a gas meter, an integrated calorimeter, an electricity meter, as well as a water meter.

The present invention described above is not limited to the configuration and operation as shown and described. That is, the present invention is capable of various changes and modifications within the spirit and scope of the appended claims.

Claims (5)

A body rotatably installed therein; A rotating plate rotatably installed in the body to interlock with the rotating body and having a conductor portion and a non-conductive portion;  A rotation sensing sensor having an inductor installed in the body to face one surface of the rotating plate and a capacitor connected to the inductor to form an LC resonance circuit together with the inductor; A power supply for supplying a voltage to the rotation sensor; A control unit which receives the detection signal from the rotation detection sensor and calculates the rotation speed of the rotating body; A display device controlled by the control unit to display information; And the rotation sensor detects the rotation of the rotating body by attenuating the voltage waveform by the eddy current generated in the conductor part when the inductor faces the conductor part. The method of claim 1, The body has a first housing having a flow path in which the rotating body is located, a second housing coupled to the first housing and having a rotation board, a circuit board having the control unit, and an installation space for accommodating the display device. And a separating member of a non-conductive material disposed between the first housing and the second housing to separate the flow path and the installation space, wherein the rotating plate is coupled to the rotating body. The method of claim 1, The rotation sensor is a meter, characterized in that the inductor and the capacitor are connected in parallel. The method of claim 1, The rotation sensor is a meter, characterized in that a plurality is installed. The method of claim 1, The rotating plate is characterized in that the conductor plate is coupled to one surface of the non-conductive plate.