JP4395318B2 - measuring device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a measuring apparatus for measuring pH, oxidation-reduction potential, ion concentration, conductivity, etc. of water or food.
[Prior art]
In the conventional apparatus of this type, an analog display using a scale and a pointer or a digital display that displays the measured value itself as a numerical value is used as a display for displaying the measured value. In particular, recently, digital display meters have been used in many cases, and not only measured values but also those capable of displaying changes over time of the measured values in graph form have been developed.
[0003]
On the other hand, it is true that there are relatively many analog-oriented users who have the impression that analog display is easier to see than digital display or that it is easier to grasp the measurement result intuitively.
[0004]
[Patent Document 1]
Japanese Patent Publication No. 7-18798 [0005]
[Problems to be solved by the invention]
However, due to the inherent problem that it is difficult to accurately read the value indicated by the needle in the analog indicator, if the measurement range, which is the width between the upper and lower limits of the measured value, is increased, the measurement accuracy of the device itself is reduced. At best, the reading error of the indicated value indicated by the pointer by the user becomes large, and the final measurement accuracy cannot be improved.
[0006]
On the other hand, in this type of apparatus, the range of measurement values varies greatly depending on the object to be measured. Therefore, if the analog indicator tries to deal with them, the number of channels for switching the range becomes extremely large. As a result, the additional work of switching the channel at the time of measurement occurs, and the labor is complicated.
[0007]
Of course, although it is a different field, there is known a method in which data is displayed in an analog display format on a digital display screen as shown in Patent Document 1, but the same problem as described above may occur.
[0008]
Accordingly, the main object of the present invention is to eliminate all the above-mentioned problems at once while taking advantage of the analog display in this type of measuring apparatus.
[0009]
[Means for Solving the Problems]
That is, the measuring apparatus according to the present invention includes a probe and a main body connected to the probe wirelessly or by wire, and is selected from among the pH, oxidation-reduction potential, ion concentration, and conductivity of the measurement object in contact with the probe. At least one of them is measured and the measured value is displayed on a display provided on the main body, and a series of scales with values assigned to required places and positions on the scale corresponding to the measured values An analog meter drawing unit that draws an indication means for pointing on the display, and the analog meter drawing unit is configured to automatically set an upper limit and a lower limit of the scale according to the measured value. To do.
[0010]
In such a case, since the measurement result is displayed in an analog display format, the user can easily grasp the change in the measured value as the movement of the instruction means. In addition, since the upper and lower limits of the scale drawn on the display are automatically set to appropriate values according to the measured values, the trouble of switching channels at the time of measurement and the reading error of the indicated value indicated by the user's pointer increase. Can be solved.
[0011]
On the other hand, in this type of measuring apparatus, it takes a certain amount of time for the measured value to stabilize. Therefore, the displayed measurement value in a state where the measurement value is not stable does not make sense. However, since it is difficult for the user to determine whether or not the measurement value is stable, a stability determination unit that automatically determines whether or not the measurement value is stable so that the user can easily grasp this. It is preferable that when the stability determination unit determines that at least the measurement value is not stable, a message to that effect is displayed on the display. Of course, conversely, if it is stable, a message to that effect may be displayed, or a message to that effect may be displayed in either state.
[0012]
As a specific embodiment for further improving the user-friendliness, a coordinate system in which one axis indicates time and the other axis indicates a measured value is drawn on the display, and the measured value is displayed in the coordinate system. A graph drawing unit that draws as a series graph is further provided, and the graph drawing unit automatically sets the upper limit and the lower limit of the other axis to an appropriate one according to the measured value.
[0013]
In order to make the display easier to see, it is preferable that the analog meter drawing unit automatically sets a value to be attached to the scale so that the instruction means is positioned at substantially the center of the scale.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0015]
As shown in FIG. 1, the measuring apparatus 1 according to the present embodiment includes a probe 2 that is brought into contact with an object to be measured, and a main body 3 that is connected to the probe 2 by a wireless or wired cable CL. The pH, oxidation-reduction potential, ion concentration, conductivity, and dissolved oxygen of the measurement object are measured and the measured values are displayed on the display 85 provided on the main body 3.
[0016]
To explain each part in detail, there are several types of probes depending on the measurement purpose: pH measurement probe, redox potential measurement probe, ion concentration measurement probe, conductivity measurement probe, and dissolved oxygen measurement probe. The probe corresponding to the measurement purpose is connected to the main body 3 and used. In the present embodiment, the following description will be given using the pH measurement probe 2 as a representative example.
[0017]
This pH measurement probe 2 is a so-called composite electrode comprising a glass electrode and a reference electrode integrated with each other. The glass electrode and the reference electrode are exposed at the tip, and this is used as a measurement object. It is comprised so that it can contact. The potential difference generated between the glass electrode and the reference electrode is output as a probe output signal. In addition, in FIG. 1, although the thing of a normal glass electrode is shown, it is not restricted to this, A needle-shaped thing with the pointed tip may be sufficient, Of course, a glass electrode and a comparison electrode are It goes without saying that other various types of probes such as separate ones may be used.
[0018]
As shown in FIGS. 2 and 3, the main body 3 is a dedicated unit that integrally includes a CPU 81, an A / D converter 82, a storage device 83, an input unit 84, a display 85, and the like as a hardware configuration. . Then, the CPU 81 and, if necessary, peripheral devices operate based on a program stored in the storage device 83, so that a measurement data calculation unit 91, a stability determination unit 92, a measurement data storage unit 93, an analog meter drawing unit 94, and functions as a graph drawing unit 95 or the like.
[0019]
The measurement data calculation unit 91 is known from the value of the probe output signal sampled at a predetermined interval by the A / D converter 82 and successively converted into a digital value, that is, a potential difference generated at the glass electrode and the comparison electrode. Measurement data indicating the pH value (measurement value) of the measurement object is calculated by comparing with a reference potential difference measured and stored in advance using a buffer solution.
[0020]
The measurement data storage unit 93 is set in a predetermined area of the storage device 83 and sequentially stores the measurement data calculated one after another by the measurement data calculation unit 91.
[0021]
The stability determination unit 92 automatically determines whether or not the pH value is stable. Specifically, the stability determination unit 92 refers to each measurement data stored in the measurement data storage unit 93 in time series, and determines them. When the change of the pH value indicated by the measurement data within a predetermined time is within a predetermined range, it is determined that the measurement value is stable. In addition, when it is determined that it is not stable, it has a function of transmitting to the display 85 stability determination display data for displaying that effect, that is, “please wait for a while” as shown in FIGS. .
[0022]
As shown in FIG. 4, the analog meter drawing unit 94 displays a series of scales 41 each having a value 43 at a required location and a pointer 42 that is an instruction means configured to be movable along the scales 41. The analog meter drawing data for drawing is generated and transmitted to the display 85. In the generation of the analog meter drawing data, the position on the scale 41 indicated by the pointer 42 is set based on the value of the measurement data calculated by the measurement data calculation unit 91, that is, the pH value. In the illustrated example, the scales 41 are arranged radially at equal intervals, and the pointer 42 is configured to rotate on the scale 41. On the other hand, the difference between the values 43 attached to the scale 41 is determined in advance, and the three pH values are displayed with a difference of 1.
[0023]
Therefore, in this embodiment, the analog meter drawing unit 94 is configured to automatically set the value 43 to be assigned to the scale 41 to an appropriate value according to the pH value indicated by the measurement data. More specifically, for example, when the pH value is “6.865” as shown in FIG. 4, “7” that is the nearest integer value is selected, and the value “7” is set to the center. And “6” and “8” are attached to the scales 41 at both ends. Then, on the scale 41 set in this way, the drawing is performed so that the pointer 42 points to the position of “6.865”.
[0024]
The graph drawing unit 95 draws the pH value measured on the display 85 as the time series graph 51 as shown in FIG. In this embodiment, time is plotted on the horizontal axis and pH value is plotted on the vertical axis, and the value 53 to be added to the vertical axis is automatically set to an appropriate value according to the measurement result.
[0025]
Specifically, this is for obtaining a series of measurement data in a predetermined time range immediately after the start of measurement, for example, from the measurement data storage unit 93, and displaying the time change of the pH value in a graph based on the measurement data. Graph drawing data is generated, and the graph drawing data is transmitted to the display 85. In generating the graph drawing data, the upper and lower limits of the vertical axis are automatically set so that the maximum value and the minimum value of the pH value indicated by the acquired measurement data are included.
[0026]
It should be noted that the graph drawing screen 5 by the graph drawing unit 95 and the analog meter drawing screen 4 by the analog meter drawing unit 94 can be selectively switched according to the user's specification. If there is a margin, these may be displayed simultaneously.
[0027]
In addition, when a probe other than for pH measurement, that is, a redox potential measurement probe, an ion concentration measurement probe, a conductivity measurement probe, or a dissolved oxygen measurement probe is used, the analog in the corresponding unit system is used. The measurement result can be displayed on the drawing screen 4 and the graph drawing screen 5.
[0028]
Further, when the pH measurement probe is used, the upper and lower limits of the scale are constant, that is, the interval between the values assigned to the scale is constant, and three integer values are displayed at intervals of 1. However, when using other types of probes, the upper and lower limits of the scale are automatically set to appropriate ones as necessary.
[0029]
Specifically, the measurement unit display 7 is automatically set to an appropriate one according to various probes. For example, “pH” is displayed on the unit display 7 in the case of a pH measurement probe, and “S / cm” (Siemens per centimeter) is automatically displayed on the unit display 7 in the case of a conductivity measurement probe. Select to display.
[0030]
Further, at least one of the unit prefixes such as “S / cm”, “mS / cm”, and “μS / cm” is selected so that the unit display 7 is appropriate according to the measured value. Is displayed. For example, the unit display 7 is set to “mS / cm” and the value given to the scale is “1”, “0.1”, or “0”. It is also possible to automatically select and display an appropriate one such as “.01”.
[0031]
Therefore, the measuring apparatus 1 according to the present embodiment configured as described above intuitively grasps the measurement result as compared with the conventional digital display by drawing the measurement result on the display 85 in the form of the analog meter drawing screen 4. It can meet the demands of analog-oriented users that it is easy to do. In the analog meter drawing screen 4, the upper limit and the lower limit of the value 43 to be attached to the scale 41 are automatically set according to the measurement result so that the pointer 42 is positioned substantially at the center of the scale 41. Thus, it is possible to eliminate the trouble of operation during measurement and to read the indicated value indicated by the pointer with high accuracy.
[0032]
In particular, in this embodiment, as shown in FIGS. 4 and 5, the measurement value itself is drawn on the digital display 6, so that there is no problem even when the measurement value needs to be read accurately. It is easy for directional users to accept.
[0033]
Also, a graph drawing screen 5 is provided, and the graph drawing screen 5 also automatically sets the upper and lower limits of the value 53 to be attached to the vertical axis indicating the measured value to an appropriate one, as in the analog meter drawing screen 4. Since the setting is made, the time series graph 51 makes it easy to read the relationship between the elapsed time and the measured value at a glance, and the usability of the measuring apparatus 1 is further improved.
[0034]
Furthermore, since the stability determination part 92 which determines whether the measured value is stable is provided and the determination result is displayed on the display 85, the user can easily know the measurement state.
[0035]
The present invention is not limited to the above embodiment.
[0036]
For example, not only an element (electrode) having a main function but also an element having another function may be incorporated in the probe to supplement the measurement. For example, temperature compensation can be performed based on temperature information of a measurement object obtained by incorporating a temperature measuring element such as a thermistor.
[0037]
In addition, the interval of the values assigned to the scale does not necessarily need to be displayed with an interval of three values. For example, when the measured value is “6.865”, it is the closest value to “ “7” is selected, and the value is assigned to the center scale, and “5” and “9” are attached to the scales at both ends. An appropriate interval other than that may be set automatically.
[0038]
Further, in this type of measuring apparatus, it takes a certain amount of time for the measured value to stabilize. For this reason, if the analog meter drawing unit operates while the measurement value is not stable, the display on the display is frequently switched during that time, which is very difficult to see. In order to effectively avoid this, a configuration may be adopted in which, when the stability determination unit determines that the measurement value is not stable, the analog meter drawing unit does not update the drawing on the display. Absent.
[0039]
In addition, the present invention can be variously modified without departing from the spirit of the present invention.
[0040]
【The invention's effect】
As described above in detail, according to the present invention, since the measurement result is displayed in an analog form on the display, the advantage of the analog meter that the user can easily grasp the change in the measured value as the movement of the instruction means can be utilized. On the other hand, the upper and lower limits of the scale drawn on the display are automatically set to appropriate values according to the measured values, which increases the trouble of switching channels during measurement and reading error of the indicated value indicated by the user's pointer. Can be solved.
[Brief description of the drawings]
FIG. 1 is an external perspective view showing a measuring apparatus according to an embodiment of the present invention.
FIG. 2 is a hardware configuration diagram showing a hardware configuration of the measurement apparatus according to the embodiment.
FIG. 3 is a functional block diagram of the measuring apparatus according to the embodiment.
FIG. 4 is a screen configuration diagram showing an example of an analog drawing screen when displaying measurement results in the embodiment.
FIG. 5 is a screen configuration diagram showing an example of a graph drawing screen when displaying measurement results in the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Measuring apparatus 2 ... Probe (probe for pH measurement)
3 ... Main body 41 ... Scale 42 ... Instruction means 51 ... Time series graph 85 ... Display 92 ... Stability judgment unit 94 ... Analog meter drawing unit 95 ... Graph drawing unit

Claims (5)

Provided with a probe and a main body connected to the probe wirelessly or by wire, a plurality of types of probes can be connected in a replaceable manner , and the pH, oxidation-reduction potential, ion concentration, Measuring at least one of the conductivity and displaying the measurement result on a display provided in the main body,
Analog meter drawing that draws a series of graduations with values at required locations, upper and lower limits of the graduations, indication means for indicating positions on the graduations corresponding to the measurement results, and measurement unit display on the display at the same time The analog meter drawing unit automatically sets the upper and lower limits of the scale drawn on the display according to the measured value, and automatically displays the unit of measurement according to various probes. A measuring apparatus configured to be set . A stability determination unit for determining whether or not the measurement value is stable is further provided, and when the stability determination unit determines that the measurement value is not stable, a message to that effect is displayed on the display. The measuring apparatus according to claim 1. The display further includes a graph drawing unit for drawing a coordinate system in which one axis indicates time and the other axis indicates a measurement value, and the measurement value is drawn in the coordinate system as a time series graph. The measuring apparatus according to claim 1, wherein the unit is configured to automatically set an upper limit and a lower limit of the other axis according to the measurement value. The measuring apparatus according to claim 1, 2, or 3, wherein the analog meter drawing unit sets an upper limit and a lower limit of the scale so that the instruction means is positioned substantially at the center of the scale. The measuring apparatus according to claim 2, wherein when the measurement value is determined not to be stable by the stability determination unit, the analog meter drawing unit does not update drawing on the display.

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