JP3778345B2 - Accuracy control method for moisture measuring device - Google Patents

Description

BACKGROUND OF THE INVENTION
The present invention relates to an accuracy management method for a moisture measuring device that measures moisture such as ready-mixed concrete, mortar, sand and the like.
[Prior art]
Conventionally, as a moisture measuring device such as ready-mixed concrete, mortar, and sand, a device that measures the moisture content by measuring the capacitance of an object to be measured has been proposed (for example, Japanese Patent Laid-Open No. 2000-314712).
[Problems to be solved by the invention]
Usually, the accuracy control in the conventional moisture measuring device is to check the accuracy of the moisture measuring device by comparing the measured value of the measured object by the moisture measuring device and the measured value by the heat drying method, such as mortar This makes it difficult to simplify the accuracy control due to the time and effort required to manufacture the object to be measured. In addition, in the case of accuracy control of the moisture measuring device by the heat drying method, a large facility such as a dryer is required, and it takes a lot of time for accuracy control, and the measured value by the heat drying method is obtained. There was a problem of including errors.
The present invention has been made in view of the above circumstances, and it is possible to easily and accurately confirm whether or not it is in a highly accurate state on a daily basis, thereby simplifying accuracy management. It is an object of the present invention to provide a method for controlling the accuracy of a moisture measuring apparatus.
[Means for Solving the Problems]
According to the first aspect of the present invention, an object to be measured such as ready-mixed concrete, mortar, or sand is accommodated in a sample case, and a measurement electrode provided on the sample case is attached to a contact assembly of the apparatus main body, and is provided on the apparatus main body. In the accuracy control method of the moisture measuring device for measuring the capacitance of the object to be measured by means of measuring the capacitance by a bridge method and obtaining the moisture content of the object to be measured, A contact provided on a calibration reference body containing a substance whose capacitance is known and whose reference value is clearly specified is attached, and the capacitance of the substance is measured by means of measuring the capacitance, and the measurement is performed. reaffirmed comparison device accuracy value and the reference value, the display unit provided in the prior Symbol apparatus main body, a display of the measured values, the difference between the measured value and the reference value when it is within a predetermined range Device is normal It is characterized in that the display of Rukoto.
According to the first aspect of the present invention, in the moisture measuring device for determining the moisture content of a measured object such as ready-mixed concrete, mortar, sand, etc. by means of measuring the capacitance of the measured object, the capacitance is known. By using this material, accurate accuracy control can be performed easily at any time in a short time, and the measured value is displayed on the display unit of the main body of the device. Since it is clearly shown, the measured value can be easily compared with the reference value, and it is also displayed on the display that the device is normal. It is possible to provide an accuracy management method for a moisture measuring apparatus that can determine whether or not it is extremely easy and can simplify the accuracy management as a whole.
According to a second aspect of the present invention, there is provided a method for controlling the accuracy of a moisture measuring apparatus, comprising: measuring a specimen such as ready-mixed concrete, mortar, or sand in a sample case; and attaching the measurement electrode provided on the sample case to a contact assembly of the apparatus main body. An arbitrary number of moisture measuring devices for measuring the capacitance of the object to be measured by means of measuring the capacitance with a high-frequency bridge method provided in the apparatus body, and determining the moisture content of the object to be measured, and an arbitrary Provided on a calibration reference body containing a substance whose capacitance is known and whose reference value is clearly specified for the contact assembly of each apparatus body, comprising a number of moisture measuring devices and management means connected by communication lines. The measured value of the capacitance of the substance measured by the means for measuring the capacitance and the management results of normality and abnormality by each device body are sent to the management means via the communication line. Ri respectively received, is characterized in that centrally control the accuracy of the moisture measuring device by the management means.
In addition to the operation of the invention according to claim 1, the accuracy management method for the moisture measuring device according to the second aspect of the present invention allows the accuracy management of each moisture measuring device to be performed at a site where any number of moisture measuring devices are installed. It is possible to provide an accuracy management method for a moisture measuring apparatus capable of centrally managing whether or not it is properly performed by a management means.
DETAILED DESCRIPTION OF THE INVENTION
Below, the quality control method of the moisture measuring device which concerns on embodiment of this invention is demonstrated in detail. First, prior to the description of the accuracy management method, a moisture measurement device that is an object of the accuracy management method of the moisture measurement device according to the embodiment of the present invention and to which this accuracy management method is applied will be described with reference to FIGS. 1 to 6. To do.
The moisture measuring device to which the accuracy controlling method of the present invention is applied is a moisture measuring device that measures moisture of ready-mixed concrete, mortar, sand, etc., and has a capacitance of ready-mixed concrete, mortar, sand, etc. The moisture content is estimated by measuring.
In addition, since the capacitance is affected by the bulk density, it is possible to estimate the moisture content with higher accuracy by measuring the mass of the sample and correcting the capacitance. In general, 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. Moreover, it is thought that the change in the capacitance measured by the moisture measuring device mainly depends on the moisture content W of the ready-mixed concrete or the like to be measured existing between the measurement electrodes.
Therefore, the water content W can be obtained by measuring the capacitance C of the object to be measured.
This moisture measuring device is based on the above principle, and the moisture measuring device will be described in detail below.
FIG. 1 and FIG. 2 show the configuration of the moisture measuring device, which includes a box-shaped lower case 13, a packing 19, and an upper case 14 that constitute the moisture measuring device main body. Between the lower case 13 and the upper case 14, a battery storage unit 50, a support substrate 21 and a display unit 60 comprising an LCD (liquid crystal), a control program for this moisture measuring device, are stored, and a capacitance calculation, etc. The CPU board assembly 2 including the CPU 80 for performing various calculations of the above, display control of the display unit 60, and the like, and the operation switch board assembly 3 constituting the operation unit 70 are incorporated.
Furthermore, an LCR series resonance circuit or a high-frequency bridge circuit described later is mounted in the apparatus main body. The operation unit 70 is configured such that the panel sheet 4 and the filter 17 are stacked on the operation switch board assembly 3 so that a large number of operation keys 3a for inputting numerical values and items can be operated on the upper case 14. .
Further, the display screen 60a of the display unit 60 for displaying various measurement results and the like is configured to be exposed on the upper case 14 from the hole 4a and the transparent part 17a provided in the panel sheet 4 and the filter 17, respectively. Visible from above the case 14.
By providing the operation unit 70 and the display unit 60 as described above, the operation is facilitated and the confirmation of display contents is facilitated.
An accommodation region 90 for the sample case 40 is formed on the upper case 14, and the contact assembly 1 that makes electrical connection with the sample case 40 can be attached to and detached from a vertical wall portion 14 a that forms the accommodation region 90. It is attached to. 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 accommodation region 90 of the sample case 40 is formed in an inclined surface shape having a large opening surface side and becoming smaller toward the bottom, thereby facilitating entry / exit of an object to be measured such as ready-mixed concrete 100.
Further, on the upper case 14, a mounting guide 40b having a wide width on the side of the vertical wall 14a and a narrow width on the insertion end side is provided, which is engaged with a mounting guide groove 40a provided on the bottom surface of the sample case 40, as shown in FIG. Thus, by mounting the sample case 40 in the direction of the arrow shown in FIG. 1 while engaging the mounting guide 40b in the mounting guide groove 40a of the sample case 40, without worrying about the positional relationship with the contact assembly 1, The sample case 40 can be accurately positioned on the upper case 14 with the contact assembly 1 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 body device but also in either the sample case or the main body device.
The display unit 60 is fixed in place using the upper fixture 7, the lower fixture 8 and the screw 200. The battery storage unit 50 includes a lower battery holder 16a and an upper battery holder 16b at the lower part of the lower case 13, and stores, for example, a single-type dry battery between the first and second battery contacts 10 and 11. It is like that.
A battery lid packing 20, a second battery contact 10, a battery lid 15, and a battery lid set screw 9 are arranged on the side wall of the lower case 13.
A communication connector 22 is arranged 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 is arranged so that it can be used with two power sources. Yes. 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 attached herewith shows the contact assembly 1 that is electrically connected to the measurement electrodes 41 and 42 provided on the sample case 40. As shown in FIG. 4, the contact assembly 1 has a pair of contact springs 32, a contact cover 34, and a contact fixture 35 with a screw 200 or the like with respect to a pair of connector receivers 36 provided on the plate 33. It is assembled using. The analog substrate 31 is attached to the back surface of the plate 33.
As shown in FIG. 1, the measurement electrodes 41 and 42 provided on the sample case 40 are connected to the pair of contact springs 32, respectively, so that the measurement exposed to the sample storage portion 45 provided inside the sample case 40. By storing, for example, ready-mixed concrete 100 between the exposed surfaces 41a, 42a of the electrodes 41, 42, the moisture content of the ready-mixed concrete 100 can be measured by the moisture measuring device, and the capacitance can be calculated.
In the above-described moisture measuring device, it is not essential to provide the sample case 40. Instead of the sample case 40, an electrode inserted into the object to be measured is connected with a cable or the like. It is also possible to measure capacitance by connecting to
FIG. 5 and FIG. 6 attached show the configurations of an LCR series resonance circuit and a high-frequency bridge circuit that measure the capacitance mounted on the moisture measuring device.
The LCR series resonance circuit shown in FIG. 5 supplies high-frequency power having a frequency f from a high-frequency power source 150 to a series resonance circuit including resistors R, r, a coil (inductor) L, and a variable capacitor C, and the capacitance of the variable capacitor C is increased. A sample case 40 accommodating the ready-mixed concrete 100 is attached to the apparatus main body, and the resistance Rx equivalently shows the electrical characteristics of the ready-mixed concrete 100 at both ends of the variable capacitor C brought into the resonance state. Then, the parallel circuit of the capacitor Cx is connected, the capacitance of the variable capacitor C is varied again, resonance is performed, and the capacitance of the ready-mixed concrete 100 is measured from the capacitance change value of the variable capacitor C at each resonance.
In addition, the code | symbol V in FIG. 5 is a voltmeter. As a result, 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 is supplied from a high-frequency power source 150 to a high-frequency bridge circuit including a high-frequency power having a frequency f and a detector DET, and connecting resistors R1, R2, R3, variable capacitors VC1, VC2, and capacitor C3 in a bridge connection. The capacitance of the two variable capacitors VC1 and VC2 is varied to balance the high-frequency bridge circuit. Next, the sample case 40 containing the ready-mixed concrete 100 is mounted on the main body of the apparatus, and is attached to both ends of the variable capacitor VC2. The parallel circuit of the resistor Rx and the capacitor Cx expressed equivalently is connected, and the capacitances of the two variable capacitors VC1 and VC2 are changed again to balance the high-frequency bridge circuit.
And the electrostatic capacitance of the ready-mixed concrete 100 which is the said to-be-measured object is calculated | required from the capacity | capacitance change value of one variable capacitor VC2. As a result, the L (inductance) component is unnecessary, the circuit configuration is more simplified than that of the LCR series resonance circuit, and the balance of the high-frequency bridge circuit that is the simplest among the high-frequency bridge circuits is utilized. From the capacitance change value of the variable capacitor VC2, it is possible to accurately obtain the capacitance of the ready-mixed concrete that is the object to be measured.
It should be noted that a conductor that affects the measured value of metal or the like is configured not to be disposed around the installation location of the sample case 40 in the apparatus main body, so that the mounting position of the metal parts or the like can be adjusted when the moisture measuring apparatus is assembled. Even if there is a slight deviation, there is no instrumental error, and the characteristics of the object to be measured can be reflected more faithfully in the measurement value, so that the accuracy of the measurement result can be expected.
Next, an accuracy management method for the moisture measuring apparatus according to the embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 7, the accuracy management method of the moisture measuring device according to the present embodiment is formed in, for example, a rectangular parallelepiped shape with respect to the pair of contact springs 32 of the contact assembly 1, and has a polymer resin inside. Alternatively, by attaching a pair of contacts 101 provided on a calibration reference body 140 containing a substance made of a ceramic material and having a known capacitance, and comparing the measured value of the substance with a moisture measuring device and the reference value The accuracy of the above-described moisture measuring device shown in FIGS. 1 to 6 is simply confirmed.
Since the substance is made of a polymer resin or ceramic that is stable in physical characteristics, such as temperature characteristics and chemical characteristics, the accuracy can be controlled without being influenced by the surrounding environment. In addition, since the electrical characteristics of the substance are stable, the confirmation period of the electrical characteristics of the substance itself can be extended.
Furthermore, the method for managing the accuracy of the moisture measuring device according to the present embodiment can be applied to the display unit 60 provided in the moisture measuring device main body if the difference between the measured value of the substance and the reference value is within a certain range. The fact that it is normal is displayed by characters such as “normal”.
As a result, it is possible to immediately grasp that the device body is normal, it is easier to understand than the numerical value, etc., it is very easy to judge whether the user is normal, and accuracy management is simplified and facilitated Can be achieved.
Next, referring to FIG. 8, an embodiment relating to an accuracy management method for performing the accuracy management of the above-described moisture measuring devices in an arbitrary number (for example, three units installed in different places) in one place. explain.
In the quality control method using the configuration shown in FIG. 8, for example, three identification numbers NO. 1 to NO. 3 are connected to each other through, for example, a modem 122, a telephone line 123 as a communication line, and a modem 124 on the host computer 130 side which is a management means so that data can be communicated with each other. The host computer 130 sends the measured value of the capacitance of the substance whose capacitance measured by 121A to 121C is known, the accuracy control result of normality, abnormality, etc. via the modem 122, telephone line 123, and modem 124. Received by the host computer 130 and processed by the host computer 130, the identification number NO. 1 to NO. For example, characters such as “normal” and “abnormal” are displayed for each of the three moisture measuring devices 121A to 121C, and unified management of the accuracy management data of each of the moisture measuring devices 121A to 121C is executed.
That is, it is possible to centrally manage whether or not the accuracy management is properly performed at the site where the moisture measuring devices 121A to 121C are installed, respectively.
【The invention's effect】
According to the present invention described above in detail, the following effects can be obtained. According to the first aspect of the present invention, in the moisture measuring device for obtaining the moisture content of the measured object such as ready-mixed concrete, mortar, sand, or the like by means of measuring the capacitance of the measured object, the capacitance is known. By using this material, accuracy control can be easily performed at any time in a short time, and the measured value is displayed on the display of the main body of the device, and the reference value is clearly indicated for the substance with known capacitance. Therefore, the measured value can be easily compared with the reference value, and the display unit displays that the device is normal. Such determination can be made very easily, and the simplification of accuracy management can be measured as a whole.
According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, it is unified that the accuracy management of each moisture measuring device is appropriately performed at the site where each moisture measuring device is installed. It is possible to provide a method for managing the accuracy of a moisture measuring device that can be managed easily.
[Brief description of the drawings]
FIG. 1 is an external perspective view of a moisture measuring device to which an accuracy management method of the present invention is applied.
FIG. 2 is an exploded perspective view of a moisture measuring device to which the quality control method of the present invention is applied.
FIG. 3 is a perspective view of a bottom portion of a storage case in a moisture measuring device to which the accuracy management method of the present invention is applied.
FIG. 4 is an exploded perspective view of a connector portion of a moisture measuring device to which the accuracy management 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 quality control method of the present invention is applied.
FIG. 7 is an external perspective view of a moisture measuring device including a calibration reference body used for accuracy management of the moisture measuring device according to the embodiment of the present invention.
FIG. 8 is a schematic block diagram showing a configuration for performing unified accuracy management of the moisture measuring apparatus 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 Communication connector 40 Sample case 41 Measurement electrode 42 Measurement electrode 50 Battery storage part 60 Display part 70 Operation part 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

Claims (2)

The measured object such as ready-mixed concrete, mortar, sand, etc. is stored in the sample case, and the measurement electrode provided in this sample case is attached to the contact assembly of the device body, and the capacitance is measured by the high frequency bridge method provided in the device body. The moisture measuring device is configured to measure the capacitance of the object to be measured by means for obtaining the moisture content of the object to be measured, and to display the measured value on a display unit provided in the apparatus body. A quality control method,
A pair of contacts provided on a calibration reference body containing a substance having a known electrostatic capacity made of a polymer resin or a ceramic material and clearly indicating the reference value is attached to the contact assembly of the apparatus body, The capacitance of the substance is measured by means for measuring the capacitance, and the measurement value is compared with a reference value so that the accuracy of the device can be confirmed. If the difference between the measured value and the reference value is within a certain range, the device is displayed as normal. If the difference is outside the certain range, the device is abnormal. It is characterized by the fact that it can be displayed, and it can easily and accurately manage the accuracy of the device in a short time without being influenced by the environment around the device, and it can also lengthen the confirmation period of the electrical characteristics Of equipment quality control Quality control method of the moisture measuring apparatus is characterized in that to allow substantially facilitated. The measured object such as ready-mixed concrete, mortar, sand, etc. is stored in the sample case, and the measurement electrode provided in this sample case is attached to the contact assembly of the device body, and the capacitance is measured by the high frequency bridge method provided in the device body. Measuring the capacitance of the object to be measured by the means to determine the moisture content of the object to be measured, and displaying the measured value on the display unit provided in the apparatus body. A measuring device;
With an arbitrary number of moisture measuring devices and management means connected by a communication line,
In an arbitrary number of moisture measuring devices, a pair of calibration reference bodies that contain a substance that has a known electrostatic capacitance made of a polymer resin or a ceramic material and that clearly indicates the reference value for the contact assembly of the device body . A contact is mounted, the capacitance of the substance is measured by means for measuring the capacitance, and the accuracy of each device can be confirmed by comparing the measured value with a reference value. When the difference between the measured value and the reference value is within a certain range, the display unit provided for the display indicates that the device is normal, and the difference is outside the certain range. In some cases, it is characterized by displaying that the device is abnormal, and can accurately and accurately manage each device in a short time without being influenced by the environment around each device, And the confirmation period of electrical characteristics Can also be lengthened, characterized in that to allow a simplified ease of quality control of each device,
Management results of normality and abnormality of each device main body are received by the management means via the communication line, and the accuracy management of each moisture measuring device is centrally performed by this management means. A quality control method for a moisture measuring device.

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