JPS618620A - Display device - Google Patents

Abstract

PURPOSE:To simplify a handling and to make a maintenance easy by giving the function of a recording meter to the function of an indication meter together. CONSTITUTION:A CPU9 performs an indication process corresponding to various key operation signals inputted via a key signal inputting circuit 3, letting each indicating element perform an indication as well as storing in order in a memory device 2 the data showing the inputted processing quantity via an analog signal input circuit 1, further letting it print the data of images via a printer interface 8 by outputting to the outer part printer the data of images. An LC display element 4 for graphic display performs a graphic display corresponding a part of the data accumulated in order via a driving circuit 5 or the processed and edited data corresponding to the prescribed time axis. A digital display LC element 6 performs the digital display of the data corresponding to the specified part of the data locus shown on the display element 4 and other data via a driving circuit 7. The handling can be thus simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a display device that continuously displays analog signals such as various process variables that are continuously input.

[Prior art]

Conventional industrial indicators that display process signals include various types of meters, strip indicators, and those that display numerical values digitally, but all of them display instantaneous values of process quantities. Only.

On the other hand, there are industrial recorders that make it possible to visually capture the temporal transition of data from data trajectories and to semi-permanently store data. It has a mechanical structure in which points indicating values corresponding to the process amount are plotted with ink on a moving recording paper at regular intervals or continuously, and it is time-consuming to maintain. Recording paper can be long, and when you want to know data from a specific period in the past, the task of searching for the trajectory of a desired time period is tedious.
It wasn't easy to use.

[Object and structure of the invention]

The present invention has been made in view of the above circumstances, and its purpose is to provide a display device that can have both the function of an indicator and the function of a recorder, and is easy to handle and maintain. be.

In order to achieve these three objects, the present invention provides a means for sampling an external analog signal and converting it into digital data, a storage means for sequentially accumulating this data, and a means for sequentially displaying the data in correspondence with the time axis. and means for extracting predetermined data from the storage means and displaying it graphically on the screen in accordance with the operation of a specific operator. Hereinafter, the present invention will be explained in detail using Examples.

〔Example〕

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a front view showing its operation display panel. In FIG. 1, 1 is an analog signal input circuit that samples a process signal P input from the outside at regular intervals and converts it into digital data, and 2 is a storage device consisting of an MO8IC that sequentially stores this digital data in time series. , 3 is a key signal input circuit for identifying and sensing the operation signal K of each operation key arranged on the operation display panel, and 4 is a key signal input circuit for identifying and sensing the operation signal K of each operation key arranged on the operation display panel; 5 is a driving circuit thereof; 6 is a liquid crystal display element that digitally displays data corresponding to a specific portion of the data locus displayed on the display element 4 and other data; 7;
8 is a driving circuit thereof; 8 is a printer ink connected to a printer (not shown) to make it possible to print out the data displayed on the display device on recording paper; faces 1 and 9 print each of these according to a predetermined program; A well-known CPU that controls components to perform predetermined operations
shows.

On the other hand, in FIG. 2, numeral 11 corresponds to 4 in FIG. 1, and is a liquid crystal display element for graphically displaying the process amount accumulated in the storage device. The screen uses the vertical axis as the time axis,
Normally, the latest data for each process quantity appears at the top of the screen and moves downward one by one. Therefore, it is always possible to grasp at a glance the instantaneous value of each process quantity and also the data transition during the time period corresponding to the interval between the upper and lower sides of the screen.

12 is a liquid crystal display element that digitally displays the reading value of each process quantity corresponding to the upper side of the screen of the display element 11; 13 corresponds to the current time or the upper side of the screen when past data is displayed on the display element 11; This is a liquid crystal display element that displays the time when data was sampled. On the other hand, 21 is a key used to scan the data trajectory of the display element 11 upwards at high speed, that is, to call up past data on the screen, and 22 is a key to be pressed to scan the trajectory downwards. 23 is a key to instruct that the time axis should be compressed to /io and the data trajectory should be displayed, and 24 is a key corresponding to the step function, which is used to move the trajectory downward one step each time it is pressed. This is the key. 25 is a key corresponding to the return function. When various data are displayed using the above keys, pressing this key instantly returns the initial state, that is, the current state on the top of the screen on the display element 11. % data is pulled out, and the display element 13 returns to the current state display with the past trajectory continuing below. 2B is a data trajectory display mode selection key, and by operating this key, in this embodiment, only one of the three trajectories on the screen of the display element 11 can be selected and displayed, or the trajectory can be changed. You can make the image flicker and display it darker. 2T uses a combination of ten keys, function keys, and numeric keys to specify a specific time in the past for which data at that time is to be recalled. Reference numeral 28 is a key used when you want to output the displayed data to an external output device, for example, a thermal printer 30 as shown in FIG. Then, the data on that screen is sequentially output to the printer. Table 31 in Figure 3
is a piece of paper on which the screen data has been copied.

That is, as shown in FIG. 4, the CPU 5 sequentially stores data indicating the process amount inputted through the analog signal input circuit 1 in the storage device 2 (step 101).
Display processing is performed in response to various key operation signals inputted via the key signal input circuit 3, causing each display element to perform a predetermined display (step 101), and if there is further operation of the key 28, the printer interface 8 to output the screen data to an external printer to print the data (step 103).

Here, the above display processing is performed as shown in FIG.

In other words, when the press of the return key 25 is detected (step 201), the current status is displayed (step 202), and when the press of the scan key 21t or 22 is detected (step 201), the current status is displayed (step 202). 203), scan display is performed in each designated direction (step 204). In other words, C.P.
U9 sequentially reads the stored data from the storage device 2 and causes the display device to display the corresponding display in rows. Similarly, if the display time is specified using the key 27 (step 205
), the data for the relevant time period is read out from the storage device 2 (step 206), and displayed (step 20T). Further, when the compression key 23 is operated (step 20B),
Compression processing, time trajectory on the screen.

After processing the data to compress it into (step 209
) Display the data trajectory (step 21o).

As a result, data trends over a period 910 times longer than normal can be viewed on a single screen. On the other hand, when the selection key 26 is pressed (step 211), a process is performed to select a trajectory of a predetermined process amount in accordance with the number of presses, etc. (step 212), and a corresponding display is performed (step 212). 213). Further, if the step key 24 is pressed (step 214), the trajectory is moved downward by one step (step 215).

There are industrial recorders that are generally installed for process monitoring.In this case, there are large data fluctuations during plant start-up as a transient state, but once the steady state is reached, the process signal is stable and shows the changes that should be observed. In many cases, data that does not exist is recorded endlessly, and this embodiment exhibits its ability in such cases. In other words, when a supervisor visits the plant intermittently to check the operating status of the plant, the indicator/recorder of this embodiment not only displays the process amount at that time, but also accumulates data over the past several dozen hours. You can easily and quickly retrieve and examine any past data with just a key operation, without having to sift through long recording sheets. In addition, it is possible to view data trends over a long period of time by displaying a compressed time axis, and to extract only the parts that require special attention and make a hard copy with a single keystroke.

In addition, in this embodiment, a liquid crystal display element is used for the display device and an MO8 circuit is used for the storage device, so that the power consumption is low, and by making it possible to drive for a long time with batteries, etc., it is possible to use it outdoors. Although it is possible to use it even in places without commercial power supply equipment, the present invention is not limited to this. For example, if a cathode ray tube is used as a display device, a much clearer image can be obtained, and once the IC memory is full, past data can be sequentially transferred to an external storage device such as a floppy disk, so that a large amount of data can be stored over a long period of time. It can also enable data storage.

〔Effect of the invention〕

As explained above, according to the present invention, there is provided a means for sampling an external analog signal and converting it into digital data, a storage means for accumulating the data, and a means for displaying the data in correspondence with the time axis. The functions of an industrial indicator and a recorder can be achieved by providing a means for displaying specific data, an operator for instructing the display of specific data, and a means for extracting and displaying data corresponding to the operation from the storage means. It is possible to realize a display device that is both user-friendly and capable of investigating arbitrary past data with extremely simple operations.

In addition, if the display device of the present invention is used, there is no need for a mechanical structure and no recording paper as in the past, so maintenance is easy and it can be used in bad environments such as rain. have

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a front view showing the operation display panel, Fig. 3 is a front view showing the usage state of the printer, and Figs. 4 and 5 are the CPU It is a flowchart which shows an example of control operation. A1... Analog signal input circuit, 211 storage device, 3... Key signal input circuit, 4.11... Liquid crystal display element that displays data locus, 5Φ... Drive circuit, 8...CPU, 21-27...Keys for instructing display contents. Patent applicant Yamatake Honeywell Co., Ltd. Agent Masaki Yamakawa (and 2 others) Figure 1

Claims (1)

[Claims] A means for sampling an analog signal continuously inputted from the outside at a predetermined time interval and converting it into digital data, a storage means for sequentially accumulating the digital data, and a plot of the digital data in correspondence with a time axis. means for sequentially displaying the trajectory on a screen; an operator for instructing the display of specific data; 1. A display device comprising means for displaying information on a screen.