JP3092957B2 - Indication error correction device for meter pointer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a meter pointer indicating error correcting device which always indicates a correct scale display position.

[0002]

2. Description of the Related Art For example, in a meter for indicating a temperature, a pressure, or a signal frequency or a signal voltage, in general, when a production quantity is small and accuracy is required, a current for actually driving a meter pointer is passed through the scale. Is attached,
For large-volume products, dials with scales are used, and the intensity of the excitation magnetic field of the meter unit is adjusted and calibrated.

[0003]

However, the above-mentioned conventional meter grading allows the maximum value and the zero to be exactly adjusted, but the meter pointer swings to an intermediate value other than the maximum value and the zero value. In this case, the indicated value does not always match the scale, and there is a problem that an error occurs according to the characteristic of the meter unit.

In view of the above, it is an object of the present invention to improve the accuracy of the indicated value of the meter pointer even when the deflection of the meter pointer is at an intermediate scale designated position.

[0005]

In order to achieve the above object, according to the present invention, the deflection range of the meter pointer is divided, and a scale value for reading the indicated value of the meter pointer is displayed at each division position. A device for correcting an error in the indication of a meter pointer provided for each of the divided positions.
A memory for storing information on correction values for each of a plurality of reference values corresponding to each of the scale values in association with each of the reference values; and a memory for storing a correction value for an input value to be displayed. Calculating means for approximately obtaining from the information on the correction value read from, and adding means for adding the correction value obtained by the calculating means to the input value and supplying the added output to the meter, Compensation stored in the memory means in association with each reference value.
Correction value setting means for setting a positive value , wherein the correction value
The setting means corresponds to each of the scale values at each of the division positions.
A reference value generating means for generating a plurality of reference values, the group
Each reference value from the reference value generation means is read from the memory means.
Adding the correction value for the reference value found,
Means for supplying the added output to the meter, the notes
The correction value for each reference value of the
And means that can be changed in response to the request .

[0006]

In the embodiment shown in the following figures, a correction value for an error of the meter pointer at each scale value is obtained, and the correction value is stored in the memory means 1.
5 is stored. Then, the correction value for accurate display of the input value is a value larger than the input value, a correction value at a scale value closest to the input value, and a value smaller than the input value. From the correction value at the scale value closest to the input value, a value approximated by, for example, linear approximation is obtained.

[0007] The correction value for the obtained input value and the added value of the input value are supplied to the drive circuit of the meter pointer as a display value for the input value.

Therefore, especially when the deflection range of the meter pointer is divided into a large number and the width of one division is small, a correction value for displaying the input value with high accuracy can be obtained almost exactly. The indication error becomes small, and the indication value of the meter pointer becomes almost accurate as shown on the scale.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a meter pointer pointing error correcting apparatus according to the present invention will be described below with reference to the drawings. The following examples illustrate the present invention using a frequency-voltage converter (hereinafter referred to as F
-V converter), in which the output voltage according to the frequency is displayed on a meter. In the case of this example, the meter is as shown in FIG.

That is, as shown in FIG. 4, this meter is of a type in which a meter pointer 1 is swung so as to rotate about a fulcrum 2.
Is matched with the minimum value (normally 0 (V)) of the value to be displayed and the maximum value (10 (V) in the case of the figure), and the maximum swing range W is determined according to the intermediate scale value at which the display is desired. The image is equally divided by the division value, and the corresponding scale is displayed by printing or liquid crystal display as shown in the figure. In FIG. 4, w is the width of the division range, and in the example of the figure, w = 2 (V). Also, s is the swing width of the meter pointer 1.

First, FIG. 1 shows a block diagram of a portion for setting (calibrating) a correction value of a pointing error of a meter pointer prior to an actual meter display.

In FIG. 1, reference numeral 11 denotes a reference voltage value corresponding to each of the scale values 0, 2, 4, 6, 8, and 10 in FIG. 4, that is, voltages of 0 V, 2 V, 4 V, 6 V, 8, and 10 V. Each reference voltage value from the reference value generation circuit 11 is supplied to a reference voltage selection circuit 12.

The reference voltage selection circuit 12 is controlled so as to select a reference value alternatively by a selection signal SE from a selection signal generation circuit 13. The selection signal generation circuit 13
It is connected to the reference voltage switching key operation unit 14, and a reference value to be selected can be selected by a key input operation on the switching key operation unit 14.

Reference numeral 15 denotes a correction value memory, in which a correction value of a pointing error of the meter pointer at each scale value is stored as described later. Selection signal generation circuit 13
Specifies the address of the memory 15 corresponding to each scale value in accordance with the reference value selection by the key input operation.

Numeral 16 denotes an up / down counter for setting the correction value. Reference numeral 17 denotes a clock generation circuit.
CK is selectively supplied to the up-clock input terminal U and the down-clock input terminal D of the counter 16 via the switching circuit 18.

The switching circuit 18 is switched by a switching signal from an up / down switching signal generating circuit 19. The up / down switching signal generation circuit 19 includes an up key 20
And the down key 21 are connected.
When both 0 and 21 are not operated, the switching circuit 18
Is adapted to an intermediate state which is not connected to any of the U side and D side, the clock to the up-down counter 16
CK is not supplied. When the up key 20 is pressed and turned on, the switching circuit 18 is switched to the U side, and the up / down counter 16 counts up the clock CK. When the down key 21 is pressed and turned on, the switching circuit 18 is switched to the D side, and the up / down counter 16 counts down the clock CK.

A correction value read from the correction value memory 15 is supplied to a preset terminal of the up / down counter 16, and when the reference voltage is changed by operating the reference voltage switching key operation unit 14, Pulse L obtained in
By D, the preset value is loaded into the up / down counter 16. Therefore, when setting the correction value, the up-down counter 16 changes the count value (correction value) with the preset value as an initial value.

Then, the reference voltage value from the reference voltage selection circuit 12 and the correction value from the correction value memory 15 converted into an analog voltage value by the D / A converter 22 are added in the addition circuit 23, and the added output is obtained. Is supplied to the meter 24, and its value is indicated by the meter pointer.

The correction value for the indication of the meter pointer is set as follows.

First, a key operation for selecting any reference voltage, for example, 2 V, is performed in the reference voltage switching key operation unit 14. Then, the selection signal generation circuit 13 selects the selection circuit 1
2, a selection signal SE for selecting the reference value 2V from the reference value generation circuit 11 is supplied, and a signal for specifying the storage address of the correction value for the scale value 2V is supplied to the correction value memory 15. Then, the correction value at 2 V stored before is read from the memory 15 and is preset in the up / down counter 16 by the pulse LD from the selection signal generation circuit 13.

At the same time, the correction value from the D / A converter 22 is supplied to the addition circuit 23, added to the reference voltage from the selection circuit 12, and displayed on a meter.

At this time, if the meter pointer position does not correctly point to the 2 V scale display, the meter pointer indicates 2 V.
The up key 20 or the down key 21 is turned on depending on which side of the scale display is shifted. The count value of the counter 16, that is, the correction value is changed according to these key operations, and is written to the corresponding address in the memory 15.

Thus, the correction value is changed, and the indicated position of the meter pointer changes according to the change. When the meter pointer correctly matches the 2V scale display, the operation of the up key 20 and the down key 21 is stopped. Therefore,
At the corresponding address in the memory 15, the correction value when the memory pointer correctly points to the scale display position remains. This completes the setting of the correction value for the reference value 2V.

The above correction value setting operation is also performed for the other scale display values 0 V, 4 V, 6 V, 8 V, and 10 V, and the correction values for each scale value are set. As shown in FIG.
It is stored at the corresponding address in the memory 15.

Then, using the correction values thus set and stored in the memory 15 , the actual display object F-
The V conversion output voltage is displayed on a meter.

Switching between the correction value setting mode and the meter display mode can be arbitrarily performed using, for example, a mode switching key. Normally, the correction value is set prior to the meter display of the measured value.

Next, an actual meter display operation using this correction value will be described.

FIG. 3 shows the F using the device according to the invention.
It is a block diagram for a meter display of a -V converter.

Reference numeral 31 denotes an input terminal of a frequency signal Sf as a measurement result. The frequency signal f is converted into a voltage Sv corresponding to the frequency by the FV conversion means 32.
Supplied to

The output voltage from the FV conversion means 32
Sv is supplied to the scale indicating position detecting means 33, and the voltage Sv
Is in which range (division range) of the scale display value is determined.

That is, the reference value is compared with the voltage Sv, and based on the comparison result, the scale indication position detecting means 33
The divided range in which the voltage Sv exists, that is, the closest scale value MU higher than the voltage Sv and the closest scale value ML lower than the voltage Sv are detected. In the example of the figure, if Sv = 9V, MU = 10 and ML = 8. Then, from the scale indicating position detecting means 33, storage addresses ADUP and ADDW of correction values for the scale values MU and ML are supplied to the correction value memory 15.

Therefore, from the correction value memory 15, the scale values MU and MU stored in the addresses ADUP and ADDW are stored.
The correction value set for the ML is read and supplied to the approximation calculation means 34.

The approximation means 34 calculates the slope (differential coefficient) kk = (ΔMU−ΔML) / w of the change of the correction value between the scale values MU and ML from the correction values ΔMU and ΔML for the scale values MU and ML. From this slope k, a correction value ΔSv for the voltage value Sv to be displayed is obtained by, for example, a linear approximation calculation. That is, ΔSv = ΔML + k (Sv−ML) where w is the width of the scale division range as shown in FIG.

The correction value Δ for the voltage Sv thus obtained
Sv is converted into an analog voltage by the D / A converter 35, supplied to the addition circuit 23, and added to the voltage Sv from the FV conversion means 32. Then, the output of the adding circuit 23 is supplied to the meter 24. Therefore, the meter pointer indicates a substantially accurate indicated value.

It should be noted that not the correction value for each scale value,
The slope k of the change of the correction value in each division scale range w may be stored in the correction value memory 15 corresponding to each division scale range. In that case, the division scale range in which the input value Sv is indicated is detected, and the detected output is used to store data in the memory 1.
From 5, k information of the inclination of the correction value in the divided scale range is read. The approximation means 34 calculates the information k
Can be used to calculate the correction value ΔSv in a short time.

Further, in the above example, the present invention is applied to the meter display of the FV converter, but it goes without saying that the present invention can be applied to the meter display of various measuring and measuring devices.

[0037]

As described above, in the present invention, the display value for the input value is approximately determined from the input value and the correction value for the two divided intermediate scale values close to the input value. Also, when the memory pointer is deflected other than zero or an intermediate scale display value, the indication of the meter pointer becomes more accurate than before.

[Brief description of the drawings]

FIG. 1 is a block diagram of an example of the present invention for setting a correction value .

FIG. 2 is a diagram illustrating an example of storage contents of a correction value memory;

FIG. 3 is a block diagram showing an example of a case where a meter display is performed using the device according to the present invention.

FIG. 4 is a diagram showing an example of a display portion of a meter.

[Explanation of symbols]

 11 Reference value generation circuit 15 Correction value memory 16 Up / down counter 23 Addition circuit 24 Meter

Continuation of the front page (56) References JP-A-1-284710 (JP, A) JP-A-3-152417 (JP, A) JP-A-4-95818 (JP, A) JP-A-62-75211 (JP) JP-A-1-272920 (JP, A) JP-A-4-89522 (JP, A) JP-A-63-67924 (JP, U) JP-B-59-18668 (JP, B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01D 18/00 G01D 3/00

Claims (1)

(57) [Claims] An apparatus for correcting a pointing error of a pointer of a meter, wherein a swing range of a meter pointer is divided, and a scale value for reading the indicated value of the meter pointer is displayed at each divided position. A memory means for storing, in association with each of the reference values, information on a correction value for each of the plurality of reference values corresponding to each of the scale values at each of the division positions; and an input value to be displayed. Calculating means for approximately calculating a correction value for from the information on the correction value read from the memory means, and adding the correction value obtained by the calculating means to the input value,
Adding means for supplying the added output to the meter; and a correction value stored in the memory means in relation to each reference value.
And a correction value setting means for setting, said correction value setting means, a plurality of groups corresponding to the respective scale values of each divided position
Reference value generating means for generating a reference value; and memory means for storing each reference value from the reference value generating means.
Add the correction value for the reference value read from
Then, the means for supplying the added output to the meter and the correction value for each reference value in the memory means are operated.
Indication error corrector of the meter pointer, characterized means for varying, in that it consists in accordance with the work input.