JP2002340835A - Precision management method for moisture measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a precision management method for a moisture measuring device, capable of always simply confirming whether the precision is good or not usually so as to simplify and facilitate precision management. SOLUTION: In this precision management method for the moisture measuring device, moisture content of material to be measured such as freshly mixed concrete, mortar, and sand is obtained by a means for measuring the electrostatic capacity of the material to be measured. The precision of the moisture measuring device is confirmed by measuring the electrostatic capacity of the material having known electrostatic capacity built in a calibrating reference body 140, and comparing the measured value with a reference value.

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a ready-mixed concrete,
The present invention relates to an accuracy control method of a moisture measuring device for measuring moisture in mortar, sand, and the like.

2. Description of the Related Art Hitherto, as a moisture measuring device for ready-mixed concrete, mortar, sand and the like, a device for measuring the moisture content by measuring the capacitance of an object to be measured has been proposed (for example, JP-A-2000-2000). 314712).

Normally, the accuracy control in the conventional moisture measuring apparatus is performed by comparing the measured value of the object to be measured by the moisture measuring apparatus with the measured value by the heating and drying method to determine the accuracy of the moisture measuring apparatus. It has been confirmed that it is difficult and troublesome to manufacture an object to be measured such as mortar, and it is difficult to simplify the accuracy control. Further, in the case of quality control of the moisture measuring device by the heating and drying method,
There is a problem that a large-scale facility such as a dryer is required, and a long time is required for accuracy control, and errors are included in measured values obtained by the heating and drying method. The present invention has been made in view of the above circumstances, and enables the user to easily and accurately confirm whether or not the state is in a state of high accuracy on a daily basis, thereby simplifying accuracy management. It is an object of the present invention to provide a quality control method for a moisture measuring device.

According to a first aspect of the present invention, there is provided a method for controlling the accuracy of a moisture measuring apparatus, comprising the steps of: measuring a capacitance of an object; In the accuracy control method of the moisture measuring device for obtaining the moisture content, the capacitance is measured for a substance having a known capacitance, and the device accuracy is confirmed by comparing the measured value with a reference value. Is what you do. Claim 1
According to the described invention, in a moisture measuring device for determining the moisture content of an object to be measured such as ready-mixed concrete, mortar, sand, or the like by means of measuring the capacitance of the object to be measured, a material having a known capacitance is used. By using it, accurate accuracy control can be easily performed at any time in a short time, and accuracy control can be simplified. According to a second aspect of the present invention, there is provided the accuracy control method for the moisture measuring apparatus according to the first aspect, wherein the substance is a polymer resin or a ceramic. According to the second aspect of the present invention, in addition to the function of the first aspect of the present invention, a material made of a polymer resin or ceramic having stable physical characteristics such as temperature characteristics and chemical characteristics is used. Therefore, accuracy control can be performed without being affected by the surrounding environment, and since the electrical characteristics of the substance are stable, the period for checking the electrical properties of the substance itself can be lengthened, which simplifies the accuracy control. It can be facilitated. According to a third aspect of the present invention, in the accuracy control method for a moisture measuring apparatus according to the first or second aspect, a reference value is specified for the substance and the display unit is provided in the main body of the moisture measuring apparatus. The measured value is displayed on the display. According to the third aspect of the invention, in addition to the operation of the first or second aspect, the measured value is displayed on the display section of the apparatus main body, and the reference value is clearly indicated for a substance having a known capacitance. Therefore, the measured value and the reference value can be easily compared, and accuracy control can be simplified. According to a fourth aspect of the present invention, in the accuracy control method for a moisture measuring apparatus according to any one of the first to third aspects, the difference between the measured value and the reference value is within a predetermined range. Then, it is characterized in that a display section provided in the apparatus main body indicates that the apparatus is normal. According to the invention set forth in claim 4, in addition to the effect of the invention set forth in any one of claims 1 to 3, the fact that the device is normal is displayed on the display unit. It is easy for the user to judge whether or not it is normal, and accuracy control can be simplified. According to a fifth aspect of the present invention, in the accuracy control method of the moisture measuring apparatus according to any one of the first to fourth aspects, the accuracy of the moisture measuring apparatus is determined by measuring a capacitance of an object to be measured. Any number of moisture measuring devices to determine the moisture content of the measured object such as concrete, mortar, sand, etc.
This moisture measurement device is provided with management means connected by a communication line, and the capacitance measured by any number of moisture measurement devices is used to manage the measured value of the capacitance of a substance having a known capacitance via the communication line. It is characterized by receiving and managing by means. According to the invention described in claim 5, in addition to the operation of the invention described in any one of claims 1 to 4,
Moisture measurement device for measuring the moisture content of the measured object such as ready-mixed concrete, mortar, sand, etc. by means of measuring the capacitance of the measured object. It is possible to centrally manage whether or not the accuracy control is properly performed by the management means.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for managing the accuracy of a moisture measuring apparatus according to an embodiment of the present invention will be described below in detail. First, prior to the description of the quality control method, a moisture measurement device to which the quality control method is applied, which is a target of the quality control method of the moisture measurement device according to the embodiment of the present invention, will be described with reference to FIGS. I do. Moisture measurement apparatus to which the quality control method is applied, which is a target of the quality control method of the present invention,
A moisture measuring device for measuring the moisture content of ready-mixed concrete, mortar, sand, etc., is to estimate the moisture content by measuring the capacitance of the ready-mixed concrete, mortar, sand, etc. Further, since the capacitance is affected by the bulk density, by measuring the mass of the sample and correcting the capacitance, it is possible to estimate the moisture content with higher accuracy. Generally, the water content W and the capacitance C can be expressed by the equation W = K · C. Here, K is a constant depending on the material. Also,
It is considered that the change of the capacitance measured by the moisture measuring device mainly depends on the moisture amount W of the ready-mixed concrete or the like, which is the measured object existing between the measurement electrodes. Therefore, by measuring the capacitance C of the measured object, the water content W can be obtained. This moisture measuring device is based on the above principle, and the moisture measuring device will be described in detail below. FIGS. 1 and 2 show the structure of the moisture measuring apparatus, which includes a box-shaped lower case 13, a packing 19, and an upper case 14, which constitute the main body of the moisture measuring apparatus. Between the lower case 13 and the upper case 14, a battery storage unit 50, a support substrate 21, and L
A display unit 60 composed of a CD (liquid crystal), which includes a CPU 80 that stores a control program of the moisture measuring device and performs various calculations such as capacitance calculation and display control of the display unit 60.
The PU board assembly 2 and the operation switch board assembly 3 constituting the operation unit 70 are incorporated. Further, an LCR series resonance circuit or a high-frequency bridge circuit described later is mounted in the apparatus main body. The operation unit 70 has a configuration in which the panel sheet 4 and the filter 17 are stacked and arranged on the operation switch board assembly 3 so that a large number of operation keys 3 a for inputting numerical values, items, and the like can be operated on the upper case 14. . The display screen 60a of the display unit 60 for displaying various measurement results and the like is provided on the panel sheet 4
And the transparent portion 17a provided in the filter 17
And the upper case 1
4 from above. Such an operation unit 7
0, the provision of the display unit 60 facilitates operation and confirmation of display contents. Also, upper case 1
4, a housing area 90 for the sample case 40 is formed, and the vertical wall portion 14 a forming the housing area 90 is provided with a contact assembly 1 for making an electrical connection with the sample case 40.
Is detachably attached. Since the contact assembly 1 is detachable, there is an advantage that maintenance and replacement of the contact assembly 1 are easy. The inner surface of the accommodating area 90 of the sample case 40 is formed in an inclined surface shape whose opening surface side is large and becomes smaller toward the bottom, thereby facilitating entry and exit of an object to be measured such as ready-mixed concrete 100. On the upper case 14, there is provided a mounting guide 40b which engages with the mounting guide groove 40a provided on the bottom surface of the sample case 40, for example, has a wide width on the vertical wall portion 14a side and a narrow width on the insertion end side, as shown in FIG. As shown, the sample case 40
By mounting the sample case 40 in the direction of the arrow shown in FIG. 1 while engaging the mounting guide 40b with the mounting guide groove 40a,
Without worrying about the positional relationship with the contact assembly 1,
The sample case 40 can be accurately positioned with respect to the contact assembly 1 on the upper case 14 to be in a measurement state. The mounting guide groove 40a and the mounting guide 40b may be provided not only in the sample case and the main unit but also in only one of the sample case and the main unit. The display unit 60 is fixed at a fixed position using an upper fixture 7, a lower fixture 8, and a screw 200. The battery housing section 50 includes a battery lower holder 16a and a battery upper holder 16b in a lower portion of the lower case 13, and houses, for example, a single type dry battery between the first and second battery contacts 10 and 11. It has become. Also, on the side wall of the lower case 13,
Battery cover packing 20, second battery contact 10, battery cover 1
5. The battery cover fixing screw 9 is arranged.
A communication connector 22 is provided on the back side of the lower case 13 so that data can be output to a printer or a computer. The AC jack 12 allows use with two power supplies. I have. A communication connector cover 23 and an AC jack cover 18 are attached to the communication connector 22 and the AC jack 12, respectively, and have a waterproof structure. FIG. 4 shows the contact assembly 1 for making electrical connection with the measurement electrodes 41 and 42 provided on the sample case 40. As shown in FIG. 4, the contact assembly 1 includes a pair of contact springs 32, a contact cover 34, a contact fixing tool 35, and a screw 200, for a pair of connector receivers 36 provided on a plate 33. Assembled using Analog board 3
1 is attached to the back of the plate 33. Then, as shown in FIG. 1, by connecting the measurement electrodes 41 and 42 provided on the sample case 40 to the pair of contact springs 32, respectively, the sample accommodation portion 45 provided inside the sample case 40 is provided.
Exposed surfaces 41a and 42a of measurement electrodes 41 and 42 exposed to
In the meantime, for example, by storing the ready-mixed concrete 100 or the like, the water content of the ready-mixed concrete 100 can be measured by the water measuring device, and its capacitance can be calculated.
In the above-described moisture measuring device, it is not essential to include the sample case 40. Instead of the sample case 40, an electrode inserted into the object to be measured is replaced with a cable or the like. It is also possible to measure the electrostatic capacitance by connecting to and measuring more. FIGS. 5 and 6 show the configuration of an LCR series resonance circuit and a high-frequency bridge circuit for measuring capacitance mounted on the moisture measuring apparatus. The LCR series resonance circuit shown in FIG.
It is supplied to a series resonance circuit composed of a coil (inductor) L and a variable capacitor C, and the capacitance of the variable capacitor C is varied to resonate. Then, the sample case 40 containing the ready-mixed concrete 100 is mounted on the main body of the apparatus. The raw concrete 10 is equivalently placed at both ends of the variable capacitor C in a resonance state.
By connecting a parallel circuit of a resistor Rx and a capacitor Cx exhibiting zero electrical characteristics, the capacitance of the variable capacitor C is re-variable to resonate, and the capacitance of the ready-mixed concrete 100 is determined from the capacitance change value of the variable capacitor C at each resonance. It measures the capacity. In addition, the code | symbol V in FIG. 5 is a voltmeter. Thus, the capacitance of the device under test can be accurately obtained from the capacitance change value of the variable capacitor VC using the resonance with the simplest circuit configuration among the LCR series resonance circuits. The high-frequency bridge circuit shown in FIG. 6 includes a high-frequency power of a frequency f from a high-frequency power supply 150, a detector DET, resistors R1, R2, R3, and variable capacitors VC1, V
C2 and a capacitor C3 are supplied to a high-frequency bridge circuit having a bridge connection, and two variable capacitors VC1 and VC2
The balance of the high-frequency bridge circuit is adjusted by changing the capacitance of the high-frequency bridge circuit. Next, with the sample case 40 containing the ready-mixed concrete 100 mounted on the main body of the apparatus, a resistor Rx equivalently represented at both ends of the variable capacitor VC2 is provided. , A parallel circuit of a capacitor Cx, and two variable capacitors VC1 and VC
The capacity of the high frequency bridge circuit is balanced by changing the capacity of the high frequency bridge circuit again. Then, the capacitance of the ready-mixed concrete 100 as the object to be measured is obtained from the capacitance change value of one of the variable capacitors VC2. This eliminates the need for an L (inductance) component, simplifies the circuit configuration as compared with the LCR series resonance circuit, and utilizes the balance of the simplest high-frequency bridge circuit among the high-frequency bridge circuits. From the capacitance change value of the variable capacitor VC2, the capacitance of the ready-mixed concrete as the object to be measured can be accurately obtained. In addition, by using a structure in which the conductor that affects the measured value of metal or the like is not arranged around the installation position of the sample case 40 in the main body of the apparatus, the mounting position of the metal part or the like during the assembly of the moisture measuring apparatus is reduced. Even if there is a slight deviation, it is possible to reflect the characteristics of the measured object more faithfully on the measured value without causing an instrumental difference, and it is possible to improve the accuracy of the measurement result. Next, with respect to the accuracy control method of the moisture measuring device according to the embodiment of the present invention, FIG.
This will be described with reference to FIG. As shown in FIG. 7, the accuracy control method of the moisture measuring apparatus according to the present embodiment is, for example, formed in a rectangular parallelepiped shape with respect to a pair of contact springs 32 of the contact assembly 1, and has a polymer resin inside. Or, a pair of contacts 101 provided on a calibration reference body 140 containing a substance having a known capacitance made of a ceramic material is attached,
By comparing the measured value of the substance by the moisture measuring device with a reference value, the accuracy of the above-described moisture measuring device shown in FIGS. 1 to 6 is easily confirmed. As the substance, a physical property such as a temperature property, and a substance made of a polymer resin or ceramic having stable chemical properties are used, so that accuracy control can be performed without being affected by the surrounding environment, In addition, since the electric characteristics of the substance are stable, the period for checking the electric characteristics of the substance itself can be extended. Still further, the accuracy control method of the moisture measuring device according to the present embodiment, if the difference between the measured value of the substance and the reference value is within a certain range, the display device 60 provided in the main body of the moisture measuring device. "Normal", for example, indicates that itself is normal
And so on. This makes it possible to immediately grasp that the main body of the device is normal, to make it easier to understand than expressing it by numerical values, etc., to make it extremely easy for the user to determine whether or not the device is normal, and to simplify and facilitate accuracy management. Can be achieved. Next, with reference to FIG. 8, an embodiment relating to an accuracy management method for centrally managing the accuracy of an arbitrary number (for example, three units installed at different locations) of the above-described moisture measuring devices in one place will be described. explain. In the accuracy control method using the configuration shown in FIG. 8, for example, three identification numbers NO. 1 to N
O. 3 moisture measuring devices 121A to 121C,
For example, a modem 122, a telephone line 12 as a communication line
3. connected to each other via a modem 124 of the host computer 130 as a management means so as to be able to communicate with each other, and the capacitance measured by each of the moisture measuring devices 121A to 121C is the known capacitance of the substance. Measured value, normal,
The quality control results of abnormalities and the like are transmitted to the host computer 13 via the modem 122, the telephone line 123, and the modem 124.
0, the data is processed by the host computer 130, and the identification number NO.
1 to NO. For example, characters such as "normal" and "abnormal" are displayed for each of the third moisture measuring devices 121A to 121C, and the unified management of the accuracy management data of each moisture measuring device 121A to 121C is executed. That is, the moisture measuring device 121A
It is possible for the host computer 130 to centrally manage whether or not the quality control is properly performed at the site where the devices 121 to 121C are installed.

According to the present invention described in detail above, the following effects can be obtained. According to the first aspect of the present invention, in a moisture measuring apparatus for measuring the moisture content of an object to be measured such as ready-mixed concrete or mortar or sand by means for measuring the capacitance of the object to be measured, the capacitance is known. By using the above substance, it is possible to provide an accuracy control method of the moisture measuring apparatus which can easily perform accuracy control at any time in a short time. According to the second aspect of the present invention, in addition to the effects of the first aspect of the present invention, a material made of a polymer resin or ceramic having stable physical characteristics such as temperature characteristics and chemical characteristics is used. As a result, accuracy control can be performed without being affected by the environment, and since the electric characteristics of the substance are stable, the period for checking the electric characteristics of the substance itself can be lengthened. A method can be provided. According to the third aspect of the invention, in addition to the operation of the first or second aspect, the measured value is displayed on the display section of the apparatus main body, and the reference value is clearly indicated for a substance having a known capacitance. Therefore, the measured value and the reference value can be easily compared, and simplification of quality control can be measured. According to the invention described in claim 4, claims 1 to 3 are provided.
In addition to the effects of the invention described in any one of the above, since the display unit indicates that the device is normal, it is easier to understand than the numerical value and the like, and it is extremely easy for the user to determine whether the device is normal. It is possible to provide a method for controlling the accuracy of a moisture measurement device that can be performed. According to the invention as set forth in claim 5, in the moisture measuring device for determining the moisture content of the measured object such as ready-mixed concrete or mortar or sand by means for measuring the capacitance of the measured object, It is possible to provide a quality control method of a moisture measurement device that can centrally manage that the accuracy control of each moisture measurement device is appropriately performed at the site where the moisture measurement device is installed.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a moisture measuring device to which a quality control method of the present invention is applied.

FIG. 2 is an exploded perspective view of a moisture measuring device to which the accuracy control method of the present invention is applied.

FIG. 3 is a perspective view of a bottom portion of a storage case in the moisture measuring device to which the accuracy control method of the present invention is applied.

FIG. 4 is an exploded perspective view of a connector portion of the moisture measuring device to which the accuracy control method of the present invention is applied.

FIG. 5 is a circuit diagram showing an LCR resonance circuit mounted on a moisture measuring device to which the quality control method of the present invention is applied.

FIG. 6 is a circuit diagram showing a high-frequency bridge circuit mounted on a moisture measuring device to which the accuracy control method of the present invention is applied.

FIG. 7 is an external perspective view of a moisture measurement device including a calibration reference body used for quality control of the moisture measurement device according to the embodiment of the present invention.

FIG. 8 is a schematic block diagram showing a configuration for performing unified quality control of the moisture measuring device according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Contact assembly 2 CPU board assembly 3 Operation switch board assembly 3a Operation key 4 Panel sheet 13 Lower case 14 Upper case 15 Battery cover 22 LCD module 40 Sample case 41 Measurement electrode 42 Measurement electrode 50 Battery storage unit 60 Display unit 70 Operation unit 90 Housing area 100 Ready-mixed concrete 121A to 121C Moisture measuring device 122 Modem 123 Telephone line 124 Modem 130 Host computer 140 Calibration reference body 150 High-frequency power supply Rx Resistance Cx Capacitor VC1 Variable capacitor VC2 Variable capacitor C Variable capacitor DET Detector L coil

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takahiro Kanno 2-2-2 Yoyogi, Shibuya-ku, Tokyo Inside Japan Railway Company (72) Inventor Junichi Kino 2-2-2 Yoyogi, Shibuya-ku, Tokyo No. Tohoku Japan Railway Company (72) Inventor Chiaki Toyoda 1-8-1, Minamimagome, Ota-ku, Tokyo Inside Kett Science Laboratory (72) Inventor Toru Hirose 1-8-1, Minamimagome, Ota-ku, Tokyo No. 1 F-term in the Kett Science Laboratory (reference) 2G060 AA14 AC01 AF10 AG11 FA01 HA02 HC01 HC13 HC19 HC24 HE02

Claims (5)

[Claims] An accuracy control method for a moisture measuring device for determining the moisture content of an object to be measured such as ready-mixed concrete or mortar or sand by means for measuring the capacitance of the object to be measured. A quality control method for a moisture measuring device, comprising measuring the capacitance of a substance and comparing the measured value with a reference value to confirm the accuracy of the device. 2. A method according to claim 1, wherein said substance is a polymer resin or ceramic. 3. The method according to claim 1, wherein a reference value is specified for the substance and the measured value is displayed on a display unit provided in the main body of the moisture measuring device. . 4. The apparatus according to claim 1, wherein when the difference between the measured value and the reference value is within a certain range, the display unit provided in the apparatus main body indicates that the apparatus is normal. The accuracy control method of the moisture measuring device according to any one of the above. 5. An arbitrary number of moisture measuring devices for measuring the moisture content of an object to be measured such as ready-mixed concrete or mortar, sand, etc. by means for measuring the capacitance of the object to be measured. Connected to the management unit, and the capacitance measured by any number of moisture measuring devices is received and managed by the management unit via the communication line, the measured value of the capacitance of the known substance. The accuracy control method for a moisture measuring device according to any one of claims 1 to 4, wherein: