JPH1164390A - Pointer indicator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pointer indicator suppressing the generation of so-called jumping and the shaking of a pointer. SOLUTION: A smoothing circuit 5 obtains the shaking angle value T(n) of a most faithful pointer 9 by a digital signal S(n) continuously changing with a prescribed measuring timing in accordance with the state of an object to be measured, obtains a variable constant N=||jT(n)-D(n$1)|-K1|/K22 from the newest shaking angle value T(n), a present indicating angle value D(n-1) and fixed parameters K1 and K2 set in advance and obtains (variable 1/N processing) an indicated target angle value D(n)=(n-1)$+ T(n)-D(n-1)}/N from the variable constant N, the newest shaking angle value T(n) and a present indicated angle value D(n-1). Displaying is executed by indicating operation by the change of the angle of the painter 9 based on this value D(n).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an instrument such as a cross-coil instrument or a stepping motor instrument which performs a pointing operation by changing the angle of a pointer, and more particularly to smoothing of the pointer pointing operation.

[0002]

2. Description of the Related Art A general pointer indicating instrument processes signals from various sensors installed on an object to be measured as appropriate, converts the signals into an appropriate pointer driving signal, and indicates the state of the object to be measured by a change in the angle of the pointer. It is indicated by. In such an indicating instrument, for signal processing from various sensors,
The sensor signal is once digitized, subjected to a predetermined process, and then converted into an analog signal again to drive the hands.

More specifically, when displaying the engine speed of a vehicle using a cross-coil meter, a pulse signal having a frequency proportional to the engine speed is output from a sensor. The voltage signal after the conversion is converted into a digital signal (digital numerical value), or the pulse signal is counted or period-measured, and the state of the object to be measured is output as a digital signal. The driving amount (angle) of the hands is calculated and processed by a control unit such as a microcomputer, thereby controlling the angle of the hands and displaying the engine speed.

In such an instrument, Japanese Patent Application Laid-Open No. H5-1808
In order to smooth the pointer indicating operation,
It is disclosed that a filter (smoothing unit) for smoothing the digital signal is provided.

[0005] This comprises a conversion unit for digitizing an input signal from the object to be measured, a drive processing unit for outputting a predetermined pointer instruction signal corresponding to the digital signal from the conversion unit,
A conversion unit configured to include a display unit that receives a drive output from the drive processing unit and operates a pointer, detects a change amount of the conversion unit output signal, and performs a digital smoothing process on the conversion unit output signal. By providing between the drive processing unit, the smoothing response characteristics are switched according to the amount of change, thereby realizing smoothing.

[0006]

According to the above prior art,
By detecting the amount of change in the output signal of the conversion unit and switching the smooth response characteristics, it is possible to quickly follow the movement of the pointer in response to the change of the object to be measured. Can be eliminated.

An object of the present invention is to further improve this conventional example and to provide an indicating instrument capable of realizing further smoothing.

[0008]

SUMMARY OF THE INVENTION The present invention for solving the above-mentioned problems is to appropriately process signals from various sensors installed on the object to be measured, convert the signals into appropriate pointer driving signals, and A pointer indicating instrument for displaying a state by a pointing operation based on a change in the angle of a pointer, wherein the most faithful pointer is indicated by a digital signal S (n) that changes every moment at a predetermined measurement timing according to the state of the object to be measured. Runout angle value T
(N) is obtained, and the latest shake angle value T (n) and the current designated angle value D (n−n) obtained at the previous measurement timing are obtained.
1) and preset fixed parameters K1 and K2
From the above, the variable constant N = || T (n) -D (n-1) |-
K1 | / K2 is obtained, and from the variable constant N, the latest shake angle value T (n), and the current designated angle value D (n-1),
Instructed target angle value D (n) = D (n−1) + ΔT (n) −
D (n-1)｝ / N is obtained, and the designated target angle value D
Based on (n), it is displayed by an instruction operation based on a change in the angle of the pointer.

Further, according to the present invention, signals from various sensors installed on the object to be measured are appropriately processed and converted into an appropriate pointer driving signal, and the state of the object to be measured is indicated by an instruction operation based on a change in the angle of the pointer. A pointer indicating instrument to be displayed, wherein the most faithful pointer swing angle value T (n) is obtained by a digital signal S (n) which changes momentarily at a predetermined measurement timing according to the state of the object to be measured. Latest swing angle value T
From (n), the current designated angle value D (n-1) of the pointer obtained at the previous measurement timing, and a fixed parameter K set in advance, a variable constant M = | T (n) -D (N
-1) | / K is obtained, and from the variable constant M, the latest shake angle value T (n), the current designated angle value D (n-1), and the fixed parameter N, the designated target angle value D (n) = D (n-
1) + {T (n) -D (n-1)} × M / N is obtained, and is displayed by an instruction operation based on the angle change of the pointer based on the instruction target angle value D (n). .

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Signals from various sensors installed on an object to be measured are appropriately processed and converted into appropriate pointer driving signals, and the state of the object to be measured is displayed by an instruction operation based on a change in the angle of the pointer. When an input signal which is a pointer indicating instrument, for example, a pulse signal having a frequency proportional to the engine speed to be measured is input from an input terminal 1, the waveform is shaped by a waveform shaping circuit 2 and then the period is measured. The circuit 3 detects the rise or fall of the input signal, counts another high frequency clock signal by the input signal, and measures the engine speed, which changes every moment at a predetermined measurement timing, for example, an 8-bit binary meter. The signal is output as a numerical value (digital signal) S (n), and the output signal S (n) of the cycle measuring circuit 3 is sent to the processing circuit 4 and used by a meter described later based on the current output signal S (n). Deflection angle value T also faithful guidance 9
(N), and further converted into a designated target angle value D (n) subjected to a smoothing process by the smoothing circuit 5, and the designated target angle value D (n) smoothed in this way is supplied to the drive circuit 6
And, if necessary, supplied to an exciting coil (not shown) of the stepping motor type instrument 8 via the output circuit 7,
Is performed by changing the angle of the engine, and the engine speed is displayed.

The smoothing circuit 5 obtains the most faithful deflection angle value T (n) of the pointer 9 based on the digital signal S (n) which changes every moment at a predetermined measurement timing according to the state of the object to be measured. , The latest shake angle value T (n),
Current indicated angle value D obtained at the previous measurement timing
(N-1) and a preset fixed parameter K
1 and K2, the variable constant N = || T (n) -D (n-
1) | -K1 | / K2 is obtained, and the variable constant N, the latest shake angle value T (n), and the current designated angle value D (n-1) are obtained.
From this, the indicated target angle value D (n) = D (n-1) + ΔT
(N) −D (n−1)｝ / N is obtained (variable 1 / N processing), or a digital signal S (n) that changes every moment at a predetermined measurement timing according to the state of the measured object. The most faithful deflection angle value T (n) of the pointer 9 is obtained, and the latest deflection angle value T (n) and the current designated angle value D (n-1) of the pointer 9 obtained at the previous measurement timing are obtained. When,
A variable constant M = | T (n) -D (n-1) | / K is obtained from the fixed parameter K set in advance, and the variable constant M, the latest shake angle value T (n) and the current From the designated angle value D (n−1) and the fixed parameter N, the designated target angle value D (n) = D (n−1) + ΔT (n) −D (n−)
1) Find｝ × M / N (variable M / N processing).

By displaying the pointer 9 in accordance with the instruction operation based on the change in the angle of the pointer 9 based on the instruction target angle value D (n), it is possible to further smooth the instruction operation of the pointer 9.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described based on an embodiment applied to a stepping motor type instrument shown in the accompanying drawings.

FIG. 1 is a block diagram showing the configuration of the embodiment. When an input signal which is a pulse signal having a frequency proportional to the engine speed to be measured is input from an input terminal 1, a waveform shaping circuit is shown. After the waveform is shaped in 2, the cycle measuring circuit 3 detects the rise or fall of the input signal, counts another high frequency clock signal by the input signal, and changes the engine at a predetermined measurement timing. The number of rotations is output, for example, as an 8-bit binary count value (digital signal) S (n).

The output signal S (n) of the period measuring circuit 3 is sent to the processing circuit 4 and the most faithful pointer swing angle value T based on the current output signal S (n) in an instrument described later.
(N), and further converted by the smoothing circuit 5 into an indicated target angle value D (n) that has been subjected to a smoothing process by a method described later, and the indicated target angle value D thus smoothed.
(N) is supplied to an exciting coil (not shown) of the stepping motor type instrument 8 via the drive circuit 6 and, if necessary, the output circuit 7, performs an instruction operation by changing the angle of the pointer 9, and displays the engine speed. Things.

Next, "variable 1 / N processing" which is an example of the processing performed by the smoothing circuit 5 will be described. The smoothing circuit 5
From the latest shake angle value T (n), the current designated angle value D (n-1) of the pointer 9 obtained at the previous measurement timing, and the fixed parameters K1 and K2 set in advance, the following 1 The variable constant N is obtained from the equation. The fixed parameters K1 and K2 are arbitrarily determined to determine the characteristics of the smoothing circuit 5 according to the specifications and characteristics of the meter 8.

N = || T (n) −D (n−1) | −K1 | / K2 [Equation 1]

Then, from the variable constant N, the latest shake angle value T (n) and the current designated angle value D (n-1),
Instructed target angle value D subjected to smoothing processing by the following two equations
Find (n).

D (n) = D (n−1) + {T (n) −D (n−1)} / N [Equation 2]

In equation (1), if the value of the first term of the numerator is equal to or larger than the value of the fixed parameter K1, the variable constant N is set to an arbitrary minimum value N (min), and the value of the first term of the numerator is calculated. Becomes "0", the variable constant N is set to a numerical value obtained by Expression 1 or an arbitrary maximum value N (max), and the variable constant N must be larger than "0".

According to such a configuration, the shake angle value T (n) which is input data and the designated angle value D (n) which is output data
By changing the ratio by varying the filter coefficient 1 / N according to the magnitude of the difference (angle difference) from (-1), the ratio is increased when the difference is large, and the ratio is decreased when the difference is small. This makes it possible to obtain characteristics that can sufficiently absorb fluctuations without impairing responsiveness.

Next, "variable M / N processing" which is another example of the processing performed by the smoothing circuit 5 will be described. Smoothing circuit 5
Is the latest shake angle value T (n) and the current designated angle value D (n-1) of the pointer 9 obtained at the previous measurement timing.
And a fixed parameter K set in advance, a variable constant M is obtained by the following three equations. The fixed parameter K is arbitrarily determined in order to determine the characteristics of the smoothing circuit 5 according to the specifications and characteristics of the meter 8.

M = | T (n) −D (n−1) | / K [Equation 3]

Then, based on the variable constant M, the latest shake angle value T (n), the current designated angle value D (n-1) and the fixed parameter N, an instruction which has been subjected to a smoothing process by the following equation (4). A target angle value D (n) is obtained. The fixed parameter N is arbitrarily determined in order to determine the characteristics of the smoothing circuit 5 in accordance with the specifications and characteristics of the meter 8, and must be larger than "0".

D (n) = D (n−1) + {T (n) −D (n−1)} × M / N [Equation 4]

In the equation (3), when the value of the numerator is “0”, the variable constant M is changed to an arbitrary minimum value M (min).
When the value of the numerator is equal to or more than a certain value, the variable constant M is calculated by the numerical formula (3) or an arbitrary maximum value M (max).
The variable constant M must be larger than “0”.

According to such a configuration, the shake angle value T (n) which is input data and the designated angle value D (n) which is output data
By changing the ratio by varying the filter coefficient M / N according to the magnitude of the difference (angle difference) from (-1), the ratio is increased when the difference is large, and the ratio is decreased when the difference is small. This makes it possible to obtain characteristics that can sufficiently absorb fluctuations without impairing responsiveness.

FIG. 2 shows “variable 1 / N” in the smoothing circuit 5.
FIG. 5 is a characteristic diagram in which the characteristics of “processing” and “variable M / N processing” are easily understood. The actual numerical values are determined by various parameters, but the latest shake angle value T (n) and the current designated angle value When the angle variation width (the angle at which the pointer 9 is about to move), which is the difference (angle difference) from D (n-1), is large, the filter coefficient (1 / N or M / N) becomes large, Conversely, it can be seen that when the angle fluctuation width is small, the filter coefficient becomes small. In particular, it can be seen that the filter coefficient 1 / N has a characteristic that changes abruptly in accordance with the angle difference.

FIG. 3 is a characteristic diagram for explaining the operation of the pointer 9 in the embodiment provided with the smoothing circuit 5 for performing "variable 1 / N processing". , The direction of the pointer 9). As a comparative example, output data after smoothing with a fixed filter coefficient 1 / N regardless of the angle difference is also shown. According to this, the output data after the variable 1 / N processing is larger than the output data after the fixed 1 / N processing, and as a result of the processing of the smoothing circuit 5, when the angular amplitude width is large, the filter coefficient is large. It can be seen that responsiveness is fast, and conversely, slow output data can be obtained when the response is small. Since the change of the filter coefficient is continuous, the movement of the pointer 9 can be smooth and natural.

It is needless to say that the present invention is not limited to the stepping motor type meter of the embodiment, but can be similarly applied to a meter such as a cross-coil type meter which performs an instruction operation by changing the angle of a pointer.

[0031]

According to the present invention, the "variable 1 / N processing" or "variable M / N processing" in the smoothing circuit 5 can realize further smoothing of the operation of indicating the hands. Even if the signals from various sensors installed on the object to be measured suddenly change or fluctuate irregularly, it is possible to suppress the occurrence of so-called needle jump and needle run-out by the above processing,
Especially in the case of indicating instruments that display the engine speed of the vehicle,
Prevents fine movement of the pointer at low rotation speeds and overshoot from high rotation speed to low rotation speed, and provides smooth pointer indications, and smooth pointer indications with less visual unnaturalness Instruments can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a characteristic diagram of the smoothing circuit of the embodiment.

FIG. 3 is a characteristic diagram of the pointer indicating instrument of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Input terminal 2 Waveform shaping circuit 3 Period measuring circuit 4 Processing circuit 5 Smoothing circuit 6 Driving circuit 7 Output circuit 8 Stepping motor type instrument (pointer indicating instrument) 9 Pointer

Claims (2)

[Claims] 1. A pointer instruction for appropriately processing signals from various sensors installed on an object to be measured, converting the signal into an appropriate pointer drive signal, and displaying the state of the object to be measured by an instruction operation based on a change in the angle of the pointer. A digital signal S (n) that changes momentarily at a predetermined measurement timing in accordance with the state of the object to be measured;
(N) is obtained, and the latest shake angle value T (n) and the current designated angle value D (n−n) obtained at the previous measurement timing are obtained.
1) and preset fixed parameters K1 and K2
From the above, the variable constant N = || T (n) -D (n-1) |-
K1 | / K2 is obtained, and from the variable constant N, the latest shake angle value T (n), and the current designated angle value D (n-1),
Instructed target angle value D (n) = D (n−1) + ΔT (n) −
D (n-1)｝ / N is obtained, and the designated target angle value D
A pointer indicating instrument for displaying by a pointing operation based on an angle change of the pointer based on (n). 2. A pointer instruction for appropriately processing signals from various sensors installed on an object to be measured, converting the signal into an appropriate pointer drive signal, and displaying the state of the object to be measured by an instruction operation based on a change in the angle of the pointer. A digital signal S (n) that changes momentarily at a predetermined measurement timing in accordance with the state of the object to be measured;
(N) is obtained, and the latest shake angle value T (n) and the current designated angle value D of the pointer obtained at the previous measurement timing are obtained.
From (n-1) and a preset fixed parameter K, a variable constant M = | T (n) -D (n-1) | / K is obtained, and this variable constant M and the latest shake angle value are obtained. From T (n), the current designated angle value D (n-1) and the fixed parameter N, the designated target angle value D (n) = D (n-1) + ΔT
(N) -D (n-1)｝ × M / N is obtained, and is displayed by an instruction operation based on an angle change of the pointer based on the indicated target angle value D (n). .