JPH01284717A - Multi-item indicator - Google Patents

Abstract

PURPOSE:To indicate process measured values of plural items on one indicator by applying process measurement signals of plural items to plural curve type arrayed phase liquid crystal elements stuck on the indication surface of the one indicator through an A/D converter. CONSTITUTION:A water level, a flow rate, and temperature are measured at process measured value detection terminals 1-1-1-3, whose measurement signals 2-1-2-3 are sent to a monitor room. Those signals 2-1-2-3 are inputted to a measurement signal converting circuit 3 and converted corresponding to the current measurement signals 2-1-2-3. Their converted signals 4-1-4-3 are inputted to a liquid crystal display circuit 7, which determines which liquid crystal element of liquid crystal 5 a voltage is applied corresponding to the converted signals 4-1-4-3 and then applies the voltage to the determined liquid crystal element. Consequently, the curve type arrayed phase liquid crystal becomes transparent and the red of the rear surface is confirmed through the front surface.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is a multi-item indicator using a liquid crystal for monitoring process measurements in a water and wastewater plant, and more specifically, a curved alignment phase indicator. This is a multi-item indicator with an inexpensive and simple circuit configuration using a liquid crystal display.

[Conventional technology]

As for the method of indicating process measurement values, a wide-angle vertical indicator and a CRT were used. Wide-angle/vertical indicators have simplified maintenance due to the number of items that can be indicated with one indicator and have moving parts, while CRTs have not been considered in terms of economy. Incidentally, related devices of this type include, for example, Japanese Patent Application Laid-Open No. 60-1
44808, JP-A No. 60-107110, and the like.

[Problem to be solved by the invention]

Conventional technology does not take into consideration the number of process measurement values of multiple items that can be measured with a single indicator, and maintenance issues, and it is necessary to install indicators according to the number of measurement items. There were problems with installation space and maintenance of the moving parts of the indicator.

The purpose of the present invention is to reduce the installation space of a monitoring operation panel indicator by allowing one indicator to indicate process measurement values of multiple items, and to improve monitoring performance through a compact configuration of the monitoring operation panel. uses a curved aligned phase liquid crystal,
The purpose is to eliminate maintenance such as span adjustment, which was necessary with conventional indicators.

[Means to solve the problem]

When indicating multiple process measurement items using a second indicator, attach a curved aligned phase type liquid crystal to the indicator and apply a voltage to display the curved aligned phase type liquid crystal. It is transparent so that the color on the back can be seen from the front. Alternatively, by utilizing the property of turning white when made opaque, a plurality of curved aligned phase type liquid crystals can be controlled in combination, thereby making it possible to indicate a plurality of process measurement items. By the method described above, it is possible to create a simple and inexpensive multi-item indicator device that controls whether or not to apply voltage.

[Effect]

A multi-item indicator is a multi-item process measurement signal (DC
4 to 20 mA input signal) is converted into a signal by an analog-to-digital converter, and the converted digital signal is used by a voltage application circuit to operate a plurality of curved aligned phase type liquid crystals pasted on the indication surface of one indicator. As a result, multiple LCDs attached to the display surface of one indicator will indicate process measurement values according to input signals, so one indicator can display process measurement values for multiple items. It becomes possible to give instructions. Therefore, conventionally, there is no restriction on the number of items that can be indicated with one indicator.

〔Example〕

A monitoring operation panel will be installed so that process measurement values for water and sewage can be grasped by monitoring operators with their own eyes, and it is possible to control something. The process measurement values are indicated by incorporating an indicator into a monitoring operation panel. Currently, there is a method for indicating process measurement values using a wide-angle, vertical indicator. 1st
To explain this method with the help of a diagram, the wide-angle type process measurement signal, the vertical type (-
The pointer and two pointers) are operating circuits inside the indicator and indicate process measurement values in response to input signals. According to this method, the number of process measurement items that can be indicated with one indicator is as follows:
Since it is limited to a maximum of 2 items, when it is incorporated into a monitoring operation panel, it is necessary to install it according to the number of process measurement items, and the shape of the monitoring operation panel becomes large, resulting in poor monitoring performance and The drawback was that it was expensive. Further, since each of the indicators has a built-in movable part, there is a drawback that maintenance such as span adjustment is required.

An embodiment of the present invention will be described below based on the drawings. Second
In the figure, multiple process measurement value indication embodiments are shown.

The water level, flow rate, and temperature are measured at the process measurement value detection terminals 1-1 to 1-3, and each measurement signal 2-1 to 2-3 is sent from the process measurement value detection terminals 1-1 to 1-3 to the monitoring room. transmit signals. Each of the process measurement signals 2-1 to 2-3 is input to the measurement signal conversion circuit 3, and signal conversion is performed corresponding to the current measurement signals 2-1 to 2-3. The converted signals 4-1 to 4-3 are input to the liquid crystal display circuit 7, and the liquid crystal display circuit l receives the converted signal 4.
-1 to 4-3, it is determined to which liquid crystal element among the liquid crystal 5 a voltage is to be applied, and the voltage is applied to the determined liquid crystal element. As a result, the curved aligned phase type liquid crystal becomes transparent and the red color on the back can be seen from the front, making it possible to monitor the current process measurement values such as water level, flow rate, and temperature. For example, the water level is 3 m compared to the full scale of 6 m, and the flow rate is 1 full scale.
0rn'/day vs. ft/day, temperature is full scale 50
If it is 10 degrees Celsius, the liquid crystal 5-1-
1~5-1-5.5-2-1~5-2-7.5-3-1
If voltage is applied to ~5-3-2 and it becomes transparent, the water level will be 3 m,
The flow rate appears to be 7 volts/day and the temperature appears to be 10°C. 'Furthermore, when the upper and lower limits set during water level measurement are reached, the liquid crystal display circuit 7 operates the liquid crystal 5-4 separately from the measurement signals 2-1 to 2-3, so that the upper and lower limits can be visually confirmed.

Figure 4 shows the structure and application example of the liquid crystal item indicator.

FIG. 4 is a side view of the monitoring surface of the monitoring operation panel, and a multi-item indicator is embedded in the monitoring surface. A liquid crystal element 5 is installed between support stands 2 of a multi-item indicator in parallel to a monitoring surface, and a painted plate 3 is installed on the back side of the liquid crystal element 5 in parallel with the liquid crystal element 5 with an interval. A space is provided between the liquid crystal element 5 and the painted plate 3 so that they contact each other so that the color of the painted plate is not visible beyond the front surface of the monitoring surface 1 of the monitoring operation panel. Voltage application wiring for the liquid crystal element 5 is wired to both ends of each of the liquid crystal elements 5-1 to 5-10, so that a commercial low-voltage power supply 8 can be used. Further, it is assumed that the switch 9 of the voltage application wiring 7 is turned ON and OFF by the output of the liquid crystal display circuit 6.

The structure of the curved aligned phase liquid crystal is shown in FIG.

Since the liquid crystal 3 has a structure in which the liquid crystal 3 is encapsulated in a transparent polymer 2 and sandwiched between plastic substrates on both sides, the liquid crystal can be processed into any size in the X-Y dimension. Further, the voltage application wiring 4 can be made transparent or opaque by connecting it to both ends of the liquid crystal. Furthermore, since it is a liquid crystal, power consumption is close to zero when voltage is applied, making it economical. Wide-angle and vertical indicators each have moving parts, and reliability and maintenance must be considered, but multi-item indicators have no moving parts, only the life of the liquid crystal, so they are highly reliable. It is durable and requires no maintenance.

As described above, the multiple-item indicator can simplify the control device and reduce power consumption to zero. Furthermore, since there are no moving parts and the device can be divided into arbitrary sizes, it is possible to provide a multi-item indicator that can easily indicate and measure a plurality of process measurement values, compared to the installation space required for one conventional indicator.

〔Effect of the invention〕

According to the present invention, without being limited by the conventional limit on the number of items that can be measured and instructed with one indicator, it is possible to specify multiple process measurement values with one indicator, thereby reducing the number of instructions. And the size of the monitoring operation panel can be reduced. Furthermore, in addition to process measurement values, upper and lower limit status displays for process measurement items can be output, thereby improving monitoring operability for monitoring operators. Furthermore, since there are no moving parts, there is almost no need for maintenance, and the simple device configuration and materials make it an inexpensive multi-item indicator.

[Brief explanation of the drawing]

Figure 1 is an external view of a wide-angle/vertical indicator, Figure 2 is an application diagram of process measurement instructions using a multiple-item indicator, Figure 3 is an operation diagram of a multiple-item indicator, and Figure 4 is monitoring of a multiple-item indicator. The operation panel installation diagram, FIG. 5, is a diagram of the structure of a curved aligned phase type liquid crystal. 1... Process measurement value detection end, 2... Each measurement signal,
3... Measurement signal conversion circuit, 4... Conversion signal, 5...
- Curved aligned phase liquid crystal, 6... Pond, 7... Liquid crystal display circuit, 8... Commercial low voltage power supply, 9... Electromagnetic flow meter. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. On the monitoring operation panel for monitoring and controlling the entire process in a water and sewage plant, a curved aligned phase type liquid crystal is used to indicate multiple process measurement values with one indicator installed. By applying a voltage, the curved aligned phase liquid crystal becomes transparent, or by applying no voltage, it becomes opaque, and the back color can be viewed from the front, making it possible to indicate process measurement values for multiple items. Multi-item indicator.