JP2804321B2 - Indicator - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a general-purpose display meter capable of setting a correspondence between an input signal value and a display value within a wide range in accordance with display symmetry.

[Conventional technology]

Electronic indicators that display current, voltage, measured values, etc. using numeric displays such as LCDs and LEDs have large and small input signal ranges and display value ranges. It was made as something. For example, as shown in FIG. 4, an indicator (4) composed of an amplifier (1) A / D converter (2) and a numeric display (3) is to be manufactured as an ammeter for displaying 1 to 100A. In such a case, the following creation procedure is required. First, since the minimum display unit according to the Measurement Law is 0.1A, select an A / D converter that has a maximum display capacity of 100.0 on the numeric display (3) and has an A / D conversion resolution of 0/1000. Select (2). The amplification factor and the zero point value of the amplifier (1) are adjusted by the adjustment volumes (1a) and (1b) so that the input signal and the displayed value are correct and correspond to each other for each indicator.

[Problems to be solved by the invention]

As described above, in the conventional indicator (4), it is necessary to select and use components depending on its type, and it is necessary to perform adjustment for each unit at the time of shipment, so that there is a problem that the manufacturing cost is increased.

Therefore, an object of the present invention is to provide a general-purpose indicator having an automatic scaling function capable of setting a correspondence relationship between an input signal value and a display value so as to be adapted to different display targets with one indicator. I do.

[Means for solving the problem]

The present invention relates to a display meter for converting A / D of input data and displaying it on a numerical display.
And the maximum number C that can be converted by the A / D converter is compared with the span value A, and the minimum display unit n is set to A
Under a condition of ≦ Cn, a minimum display unit determination unit that determines a predetermined integer value group including 1 such as 1, 2, 5, or 10 as a minimum value, a span value A, and a zero point value B Corresponding A / D
An input zero / span setting unit for specifying input data a and b to be converted, and an arithmetic operation of D = [(AB) / (ab)] × X + B is performed on the input A / D conversion value X. And a scaling unit for performing a scaling operation and outputting a display value D to a numerical display.

[Action]

Since the display unit of the present invention switches the display unit so that the display value range falls within the display capability of the numerical display, a wide range of display can be performed with one numerical display.

The display span value A is calculated by the calculation in the scaling section.
And the zero point value B are automatically associated with the A / D conversion values a and b, so that there is no need to use a dedicated A / D converter.

Therefore, one indicator can be used as an indicator for a wide range of purposes.

〔Example〕

The configuration of the present invention will be described with reference to FIGS.

In FIG. 1, (5) is an input terminal for an analog signal,
(6) is an amplifier, (7) is an A / D converter, (8) is LCD, LE
Numerical display such as D, (8a) is a driving circuit of the numerical display (8), (9) is a zero span setting unit for inputting a span value A and a zero point value B of a display amount, and (10) is a minimum display unit. In the decision part,
The maximum number C that can be displayed on the numeric display (8) is compared with the span value A, and the minimum display unit n is set to 1, under the condition of A ≦ Cn.
The smallest power is determined from the powers of 2, 5, and 10. (1
1) is a minimum unit display section for displaying the selected minimum unit near the numeric display (8). (12) is an input span setting unit for specifying input data a and b to be A / D converted corresponding to the span value A and the zero point value B. (13) is a scaling unit, and D = [(A−
B) / (ab)] × X + B is performed and the display value D is output to the numerical display.

The operation of the display unit (14) with a scaling function will be described in order.

First, a span value A, eg, 3000 (mA), which is the maximum display amount, and a zero point value B, eg, 0, are set by the zero span setting section (9). Then the minimum display unit selection part (10)
Is compared with the maximum number C which can be converted by the A / D converter (7), for example, 2000 as shown in FIG.
Under the condition of ≦ Cn, two minimum powers are selected from the powers of 1, 2, 5, and 10.

Under the conditions of A = 3000 and C = 2000 described above, n = 2, and this value is displayed near the numeric display (8) by the minimum unit display section (11). It is a unit. The display of mA is performed by separately preparing a display piece on which this is printed and fitting it into the numeric display (8) from the side.

Next, scaling is performed. That is, an electric signal that detects a span value A, for example, 3000 mA, and an electric signal that detects a zero point value, for example, OmA, are input to the input terminal (5).
At each input, it is specified by the input span setting value (12). Then, the scaling unit (13) then A / D
The digital values a and b output from the converter (7) are stored as values corresponding to A and B, respectively.

Thereafter, the scaling unit (13) calculates D = [(AB) /
(A−b)] × X + B is calculated and the numeric display (8)
Output the display value D. In this scaling, the digital values a and b are linearly converted into display values A and B as shown in FIG.

Next, an example of incorporating the scaling function of the present invention is shown in FIG.
This will be described with reference to the bar graph indicator (15) shown in the figure.

As shown in FIG. 5, the bar graph indicator (15) has a numeric display and a liquid crystal display (17) in which a bar graph and the like are formed on a front frame (16). The bar graph indicator (15) automatically scales and displays input data, and generates a control output when the input data exceeds a preset value. Further, it has a setting function for performing various settings.

FIG. 5 shows all the display patterns of the liquid crystal display (17) collectively for convenience of explanation, and these display patterns are selectively displayed according to this function at the time of operation.

Explaining this display pattern, (8) is a numeric display, (8b) is a maximum value display section of the display, (8a) is a measurement display section, (19) is a display point display on a bar graph (20). Preset value display section in which elements are arranged along a bar graph, (19), (21) is a percentage scale display, (22) is four setting operation display sections, (23) is eight mode display sections, ( 24) are three control state display sections. The mode key (23 ') and the increment key (2
4 '), a decrement key (25) and a set key (26) are embedded and arranged.

Each function of the bar graph indicator (15) of the present invention will be described in order.

First, the setting function will be described. The setting types are
There are zero point setting, span setting, decimal point setting, preset value setting, and display brightness setting.

This setting operation is performed as shown in the flowchart of FIG. That is, the setting subroutine is periodically called during the normal counting display. At this time, when it is detected that the mode key (23 ') is pressed, the four setting operations on the lower side of the liquid phase display (17) are performed. The display (22) is displayed, and the setting operation is started.

When the setting subroutine is called, the key timer is turned on first. This is because the key operation is automatically exited from the setting mode when the key operation is not performed for a predetermined number of seconds, for example, 5 seconds.

Next, press the mode key (23 ') and the increment key (2
4 '), whether the decrement key (25) and the set key (26) are pressed is checked in order, and key input processing is performed. If the mode key (23') is pressed, a mode flag is set. The number of times the mode key (23 ') is pressed after the mode flag is set is also counted and stored in the mode counter (27). This counter is of a ring counter type with the maximum number of all modes. If the increment key (24 ') is pressed, the set counter (2
8) is incremented by one, and if the decrement counter (25) is depressed, the set counter (28) is decremented by one. When the increment key (24 ') or the decrement key (25) is continuously depressed, the counting is continuously performed to increase the counting speed. For example, perform key check several times, measure the time that is kept pressed, and when this exceeds a certain time,
Until the key is turned off, counting is continuously performed at predetermined intervals on the tenth side or one side. If the set key (26) is pressed, the set flag is set. When exiting this key check subroutine, if any key is pressed, the key timer is cleared to zero. If the key timer has counted up, all the flags are cleared and the process returns to the main routine for displaying the normal count. If not, the setting operation is continued. Next, looking at the mode flag, if this is set, the display returns to the normal count display. If not set, it is determined whether or not the zero span has been set. This is performed by looking at a zero span flag described later, in order to prevent a preset value or the like from being set in a state where the zero span setting has not been made. Once the determination of the zero span setting is completed,
According to the contents of the mode counter (27), the zero point value,
Move on to the setting mode of span value, upper limit value, upper / lower limit value, lower limit value, lower / lower limit value, and display brightness. When entering each mode, one of the mode displays (23) at the upper left of the liquid crystal display is selectively displayed, and a display corresponding to the set mode is displayed on the liquid crystal display (17).

For example, in the case of zero point setting, span setting, upper limit value, upper limit value, lower limit value, and lower limit value, the count value of the set counter (28) is displayed on the numeric display (8).

Then, it is determined whether or not the set flag is set. If the set flag is set, the contents of the set counter are stored as a zero point value, a span value, an upper limit value, a lower limit value, and the like.
In this case, when both the zero point value and the span value are stored, a zero span flag is set. Then, returning to the beginning of the setting subroutine, the key check is restarted. In order to end such a setting mode, the keys (23 ') to (26) need not be touched for a predetermined number of seconds, for example, 5 seconds as described above.

The bar graph display (15)
Can be set at any time during the operation of. In the normal count display, for example, as shown in FIG. 7, a 100% display with respect to the span value A of the input signal is displayed by a bar graph (19), and the count value of the input data is displayed by a numeric display (8a). The value A is digitally displayed as a maximum value display section (8b).
The upper limit, upper limit, lower limit, and lower limit are lit by the preset value display section (20) in correspondence with the display of the bar graph (19).

The bar graph indicator (15) of the present invention has various other features, which will be described in order.

When the numerical value is displayed on the bar graph (19), when the input is smaller than the zero point value B and when the input is larger than the span value A, the bar graph (19) is not displayed at all.
Alternatively, the display becomes 100% display and overflows, and the content cannot be grasped. To solve this, separately, 0
A small display point such as an LED is provided on the dot side and 100% side (Japanese Utility Model Application Laid-Open No. 168016). However, in this case, a display element is required separately. Also, it is not clear from this display alone how much overflow occurs. Therefore, FIG. 8 (a)
As shown in (b), the amount of overflow is turned on and off from the zero point value side or the span value side and blinks.
The processing procedure in this case is as shown in the flowchart of FIG. That is, the output of the scaling unit (13) is 0
If it is below, the polarity is inverted and given to the drive circuit (8a) to make it blink. If the output of the scaling section (13) is equal to or larger than the span value, the span value is subtracted from the digital output, and the drive circuit (8a) is displayed blinking starting from the maximum value side.

Next, a control output generation operation based on preset values such as an upper limit value and a lower limit value will be described. These preset values turn on all display elements between the upper limit and the lower limit in the bar graph type preset display section (20) as shown in FIG. 7, and the upper limit and the lower limit are each one. The display element is lit and displayed. If the output of the scaling unit (13) is between the upper and lower limits, a GO output (24) above the liquid crystal display (17) is generated as shown in FIG. If the value goes above or below the value in this range,
Upper limit output and lower limit output occur.
When the values exceed the lower and lower limit values, respective control outputs are generated. At this time, the control status display section (24) above the liquid crystal display (17)
Is displayed as H or L.

Here, the determination as to whether or not the preset value such as the upper limit value is exceeded is performed by considering the virtual set value as shown in the flowchart of FIG. 10 so that the chattering operation does not occur.

In other words, when the upper limit or the upper limit is exceeded, the set value is added to the value of the minimum unit of digital display x 10 to make a virtual set value, which is compared with the input data for one second. Is exceeded, an output indicating that the set value has been reached is generated. If this control output does not occur during this one second,
A value obtained by adding the minimum unit × 5 to the set value is set as a virtual set value.
Compare with input data for one second. If no control output is generated during this time, a value obtained by adding the minimum unit × 2 to the set value is set as a virtual set value, and further compared with the input data for one second. If no control output is generated even by this, the determination is made by returning to the original set value. This chattering prevention process is performed by subtracting the minimum unit Xm from the set value for the lower limit or the lower lower limit. The setting operation of the bar graph indicator (15) of the present invention can be performed by remote control in addition to the embedded key switches (23 ') to (26) provided on the front panel.

 An embodiment in this case will be described with reference to FIGS. 11 and 12.

The remote control device (39) of this embodiment uses near-infrared light as a data transmission means. As shown in FIG. 11, an optical communication receiver (15) is provided in the main body of the bar graph indicator (15). 40), ID code and data confirmation display section (41)
A transmitter (43) and four setting switches (44) to (4) corresponding to the setting switches of the main body are provided on the portable operation device (42).
7), a digital switch (48) and an ID code setting switch (49) are provided.

As shown in FIG. 12 (a), the optical communication receiver (40) has a base end of an optical fiber (50) having a front end exposed at a lower portion of a front frame (16) and a light receiving element of a receiving section (40). It is optically coupled to (51) and extracts digital data serially transmitted by the output of the light receiving element (51). Confirmation display (4
1) is for digital data received by the receiver (40).
It has a function of displaying a D code and input data on a numeric display (8) and a bar code display (19) for confirmation.

As shown in FIG. 12 (b), the remote control device (39) has the light projecting unit facing the front of the bar graph indicator (15) and the four setting switches (44) to (4) of the operation unit (42). By pressing (47), the four setting switches (23 ')
The same settings can be made as when (26) is operated. The ID code is a bar graph indicator (15)
By using the digital switch (48) to specify this code and pressing the ID code setting switch (49), it is possible to operate multiple bar graph indicators (15) with one operation unit (42). You can do it.

The bar graph indicator (15) of the present invention is provided with a memory (60) for storing sampling measurement data and upper and lower limit operation data for a predetermined period in the main body as shown in FIG. Can be collected up to a predetermined time before. In this case, the bar graph indicator (1
5) includes a transmitter (61) using a near infrared ray or an ultrasonic wave, a transmission operation start switch (61a), and a transmission confirmation display circuit (61).
b) is provided. In addition, receiving devices for data collection (6
2) As driven by the CPU (63). A data check unit (65) for checking the data content of the receiving circuit (64), a memory (70) having a capacity for storing data for the number of data to be collected at one time, and a display unit for confirming that the data has been received ( 66) and a personal computer interface (68) for transmitting and receiving data to and from a personal computer (67). The receiver (62) is driven by a built-in battery (68 ') at the time of data collection, but an adapter (69) for converting a commercial AC power supply to a DC low voltage at the time of connection with a personal computer (67). used.

The bar graph indicator (15) of the present invention can collectively collect various settings such as preset values and a large number of measurement data by linking a large number of indicators with a communication line.

Fig. 14 shows data collection using a local area network (LAN). Each bar graph indicator (15) is connected to a communication line (71) via a LAN interface (70 '). Have been. The communication line (71) is connected to a host computer (72) via a LAN interface (70 '). In the illustrated example, the modems (73) and (73) are used and the connection is made through the telephone line (74). However, when the host computer (72) is installed in the factory, the LAN interface (70 ') and the host computer (72) may be directly connected.

The remote control device (39), the data collection device, and the data transmission / reception device via a communication line described as application examples can incorporate all of these functions into the bar graph indicator (15). One or more can also be incorporated.

〔The invention's effect〕

Since the indicator of the present invention has an automatic scaling function, one indicator can be used as an indicator for various purposes, and it is necessary to manufacture and selectively use different types of indicators according to the purpose of use. Absent. Therefore, it is possible to reduce the manufacturing cost and provide a convenient indicator for use.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the indicator of the present invention,
FIG. 2 is a flowchart showing a procedure for determining a minimum display unit, and FIG. 3 is a conceptual diagram of scaling. FIG. 4 is a block diagram showing a conventional indicator. FIG. 5 is a view showing a front panel of a specific embodiment of the indicator of the present invention, FIG. 6 is a flowchart for explaining setting functions in the indicator shown in FIG. 5, and FIG. 7 is a normal display of the front panel. FIGS. 8 (a) and 8 (b) show the state of the wrapped display at the time of overflow, and FIG. 9 is a flowchart for explaining the processing of wrapped display at the time of overflow.
FIG. 10 is a flowchart for explaining virtual value processing for preventing chattering of a control output based on a preset value,
11 and 12 (a) and (b) are a block diagram and an external view showing a configuration of a remote control device, FIG. 13 is a block diagram showing a configuration of a data collection device, and FIG. 14 is a local area network. It is a block diagram which shows a data transmission / reception system.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01D 3/02 G01R 19/165

Claims (1)

(57) [Claims] An A / D converter for converting an input data into an A / D converter and displaying the data on a numeric display. A zero-span setting unit for setting a span value A and a zero-point value B of a display amount. A minimum display unit determining unit that compares the maximum possible number C with the span value A, and determines the minimum display unit n to be the minimum among predetermined integer value groups including 1 under the condition of A ≦ Cn; An input zero / span setting unit that specifies input data a and b to be A / D converted corresponding to a span value A and a zero point value B, and D = [(A−B ) / (Ab)] × X + B, performing scaling, and outputting a display value D to a numerical display.