JP2844314B2 - Information display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information display device,
In particular, the present invention relates to an information display device that displays various kinds of information composed of patterns such as characters and graphic symbols by display elements arranged in a vertical and horizontal matrix.

[0002]

2. Description of the Related Art In general, an information display device of this type uses an LED as a display element because of its long service life, multi-color display, moving image display, etc. In particular, the LED is driven by a direct current. In addition, since the luminous intensity is proportional to the drive current value, a switching type DC stabilized power supply or the like is often used as a power supply device for supplying the drive current. In general, in an outdoor information display device having a display surface having a size of 2 m × 3 m, LEDs are arranged at a pitch of about 10 mm in order to perform finer display. In this case, the number of LEDs is 200 × 300
= 60000.

On the other hand, the required power capacity of one LED is 0.2
The power capacity required for the entire information display device is
An enormous capacity of 0.2 × 60000 = 12 KW is required. However, from the viewpoint of productivity, a switching type DC stabilized power supply generally has a capacity of up to about 3 KW.
As a power supply for the information display device, a plurality of power supply devices are connected and used in parallel.
Four KW stabilized DC power supplies are connected in parallel. Further, when a failure occurs in any one of the power supply units, the other power supply units connected in parallel become overloaded and cause a secondary disaster. In such a case, the power supply from all the power supply units is stopped, and all information displays disappear.

[0004]

Therefore, in such a conventional information display device, when a failure occurs in one of the power supply devices, the other power supply device becomes overloaded, and
If one of the power supply units fails, the power supply from all power supply units is stopped and all information displays are erased. If the device is displaying important information, for example, if it is displaying important information to ensure the safety of the road user, failure of only one power supply will endanger the road user. However, there is a problem that the system is exposed, which causes a reduction in the reliability of the system. The present invention is intended to solve such a problem, and provides a highly reliable information display device capable of accurately displaying the initial information content even when a failure occurs in any of the power supply devices. It is intended to be.

[0005]

In order to achieve such an object, an information display device according to the present invention is connected in parallel to supply power to each display element and to provide a fault in its own device. When a failure occurs, a plurality of power supplies each outputting a predetermined failure signal, and in accordance with the failure signal from any one of the power supplies, a required power supply capacity required to display the current symbol and each of the remaining power supply capacity are displayed. A control unit that compares the power supply capacity that can be supplied from the power supply device and, when the required power supply capacity exceeds the power supply capacity, reduces the power supply capacity consumed by the display element.

Further, a drive control means for controlling the drive of each of the display elements constituting the whole or a part of the display surface based on a predetermined control signal is provided, and the control section requires the required power supply capacity to exceed the supply power supply capacity. In such a case, the driving of each display element constituting a part of the display surface is stopped by outputting a control signal. Further, a drive control means for controlling the drive of each display element constituting all or a part of the display surface based on a predetermined control signal is provided, and when the required power supply capacity exceeds the supply power supply capacity, By outputting a control signal having a predetermined duty ratio, each display element constituting the whole or a part of the display surface is intermittently driven.

[0007] When the required power supply capacity exceeds the supply power supply capacity, the control unit is configured to display the information indicating the initial information based on the display data indicating the new design in which the required power supply capacity is smaller than the current design. Each display element is driven. Also, the control unit has a plurality of power saving means for suppressing the power supply capacity consumed by the display element, and when the required power supply capacity exceeds the supply power supply capacity, the control unit sequentially controls each power saving means based on a predetermined standard. It is intended to be implemented. Further, the control unit executes each power saving means in ascending order of a decrease in visibility of display contents due to execution of each power saving means.

[0008]

Therefore, the control unit determines the required power supply capacity required for displaying the current symbol and the supply power supply capacity that can be supplied from each of the remaining power supply apparatuses in response to a failure signal from any of the power supply apparatuses. If the required power supply capacity is larger than the supply power supply capacity, the power supply capacity consumed by the display element is reduced.

[0009]

Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of an information display device according to an embodiment of the present invention. In FIG. 1, 11 to 14 supply driving current to respective LEDs 31 which are connected in parallel and constitute a display element. In addition, when a failure occurs in the own device, failure signals S1 to
Power supply device that outputs S4, 2 is LED31, LED31
, A display unit composed of a plurality of display dot circuits 21 to 2n having a storage circuit 33 for storing display data D for the LED 31 and a display circuit D for driving each display dot circuit 2
A predetermined display data D is output to the storage circuits 33 of 1 to 2n, and the control is performed in accordance with the failure signals S1 to S4 from any of the power supply devices 11 to 14 and the power supply capacity necessary for displaying information. This is a control unit that outputs the signal CNT.

The display dot circuits 21 to 2m which are a part of the display dot circuits 21 to 2n and correspond to the portions for displaying the graphic symbol information are provided with the LEDs 31 based on the display data D in the storage circuit 33. Control signal C
An AND gate (drive control means) controlled by NT is provided, and a control signal CNT from the control unit 1
The supply of the display data D output from the storage circuit 33 to the transistor 32 is controlled.

Next, the operation of the present invention will be described with reference to FIG. The control unit 1 forms a pattern composed of characters and graphic symbols in response to a display request from the outside, and stores the display data D corresponding to each display dot position in the storage circuit 33 of each of the display dot circuits 21 to 2n. And the storage circuit 33 of each of the display dot circuits 21 to 2n stores the display data D from the control unit 1 in response to this. In response, the display data D is output from the storage circuit 33 of the display dot circuits 2m + 1 to 2n to the transistor 32 to drive the LED 31, and the display is displayed on one of the AND gates 34 from the storage circuit 33 of the display dot circuits 21 to 2m. Data D is output.

FIG. 4 is a timing chart showing signal waveforms at various parts of the information display device of FIG. 1. FIG. 4A shows failure signals S1 to S4 output from power supply devices 11 to 14, and FIG.
(B) is a control signal CNT output from the control unit 1,
(C) is display data D output from the storage device 33,
(D) shows ON / OFF of the LED 31. Each of the power supply devices 11 to 14 has its + and-output terminals connected in parallel and supplies power to each of the display dot circuits 21 to 2n in common. As shown in a section T0 in FIG. When the operation is normal, the "L" level is output as the failure signals S1 to S4. The control unit 1 monitors the operation status of each of the power supply devices 11 to 14 with the failure signals S1 to S4, and determines that the power supply devices 11 to 14 are operating normally when all the failure signals S1 to S4 are at the “L” level. And the control signal C
"H" level is output as NT.

As a result, for each of the display dot circuits 21 to 2m to which the control signal CNT is supplied, the control signal CNT of "H" level is input to the other input of the AND gate 34.
Is input, and the display data D stored in the storage circuit 33 is supplied to the transistor 32 to drive the LED 31, and each LED 31 displays a symbol according to the display request. In FIG. 4C, the display data D of “H” level indicating the lighting is output from the storage device 33, and the control signal CNT of FIG. 4B is at “H” level. LED 31 is "ON", that is, lit.

Here, any one of the power supply devices 11 to 14,
For example, when the power supply device 11 detects a failure that has occurred in the power supply device itself and changes the failure signal S1 to the “L” level, the control unit 1 detects this and recognizes that a failure has occurred in the power supply device 11. Then, the power supply capacity that can be supplied after the occurrence of the failure, that is, the supply power supply capacity, and the power supply capacity that is necessary to display the current display symbol, that is, the necessary power supply capacity, are calculated and compared. First, regarding the supply power capacity, since one of the four power supply devices has failed and power cannot be supplied, the power supply capacity is assumed to be 3/4 of the normal power supply capacity. The required power supply capacity is obtained by calculating the lighting ratio of the display element with respect to the current symbol, that is, the ratio of the lighting display element with respect to all the display elements, from the display data D output to each display dot circuit, and comparing the two.

Therefore, if the required power supply capacity is smaller than the supply power supply capacity, the control unit 1 must make sure that the other power supply devices 12 to 14 do not become overloaded even if the display of the current symbol is continued. Then, the control signal CNT is maintained at the “H” level, and each of the display dot circuits 21 to
Drive 2m. On the other hand, when the required power supply capacity is larger than the supply power supply capacity, when the display of the current symbol is continued, it is determined that the other power supply devices 12 to 14 are overloaded, and the section of FIG. As indicated by T1, the control signal CN
T is changed to “L” level.

Thus, each of the display dot circuits 21 to 2n
Of the display dot circuits 21 to 2m to which the control signal CNT is supplied, one of the inputs of the AND gate 34 is at the “L” level, and the transistors are irrespective of the contents of the display data D stored in the storage circuit 33. "L" level is output to the LED 32, and the LED 3 is turned off.
1 is stopped (OFF). FIG. 6 is an explanatory diagram showing an example of a symbol display by the display unit 2. FIG. 6A shows an initial display symbol when all the power supply devices are in a normal state.
(B) shows a display symbol when any one of the power supply devices has failed.

In FIG. 6, reference numeral 61 denotes an entire display area; 62, a graphic symbol display area for displaying graphic symbols for calling various kinds of attention; and 63, a character display area for displaying characters indicating detailed contents of information. The control signal CNT from the control unit 1 is supplied only to each display dot circuit constituting the graphic symbol display area. Therefore, when a failure occurs in any of the power supply devices, each of the display dot circuits 2
Only the display of the symbol symbol display area 62 where symbol symbols are displayed, for example, 1 to 2 m, is stopped, and the power supply capacity required for display is reduced. As shown in FIG. Character display in the remaining character display area 63 is continued according to the power supply capacity of the apparatus.

As described above, when a failure occurs in any of the power supply devices, the power supply capacity that can be supplied by the remaining power supply devices is compared with the power supply capacity required for the current symbol display.
When the power supply capacity required for display exceeds the power supply capacity that can be supplied, the display of an area that is a part of the design and that can sufficiently transmit information is stopped in another part even if the display is stopped. Therefore, even if a failure occurs in any of the power supply devices, the display is continued by the remaining power supply device, the original information content can be accurately displayed, and a highly reliable information display device is realized. You.

In the above description, a part of the display surface is fixedly selected in advance as an area to be stopped in response to a failure of the power supply device, and each LED 31 corresponding to the area is selected.
Although only the case where only the control signal CNT is used has been described, all the LEDs 3 constituting the display surface are controlled.
1 for each LED or a plurality of LEDs 3
The control signal CNT can be output in the unit of a predetermined block composed of 1 and each LED 3 corresponding to an arbitrary part of the display surface is controlled.
1 may be controlled. This makes it possible to flexibly select the position and size of the area where the display is stopped in response to the failure of the power supply device. By removing the restriction and changing the size of the display stop area in accordance with the power supply capacity reduced due to the failure, it is possible to continue the display with the maximum visibility.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 2 is a block diagram of an information display device according to a second embodiment of the present invention, and the same or equivalent parts as those described above (FIG. 1) are denoted by the same reference numerals. In FIG. 2, a control signal CNT from the control unit 1 is
AND gate 34 of all display dot circuits 21 to 2n
Are supplied in common. Now, when a failure occurs in the power supply device 11 and the failure signal S1 changes to “H” level, the control unit 1 detects this and calculates and compares the supplied power supply capacity and the required power supply capacity as described above. .

Here, when the required power supply capacity is larger than the supply power supply capacity, it is determined that the other power supply devices 12 to 14 are overloaded when the display of the current symbol is continued. As shown in a section T2 in FIG. 4, a pulse-like control signal CNT having a predetermined duty ratio is output.
As a result, the pulse-like control signal CNT is input to the AND gates 34 of the display dot circuits 21 to 2n, and the display data D from the storage circuit 33 is output intermittently to the transistor 32. CNT
, A current corresponding to the lighting time flows.

In this case, the duty ratio is calculated from the power supply capacity of the remaining power supply device and the lighting rate of the symbol to be displayed, and the lower limit thereof is determined based on the brightness and visibility of the display. For example, when one of the four power supply devices fails, the power supply capacity becomes 3/4 of the normal capacity, and the duty ratio of the control signal CNT is also set to 3/4.
Or, by setting it to less than that, it is possible to reliably avoid overloading the remaining power supply devices. In addition, although flickering of the display occurs in response to the blinking of the LED 31, flickering at a high speed within the remaining time of the human eye can avoid flickering in visual recognition.

Therefore, by selecting a duty ratio such that the required power supply capacity is smaller than the supply power supply capacity and outputting a control signal CNT in accordance with the duty ratio, the power supply capacity required for display is reduced. Even if a failure occurs in the power supply device, the display is continued by the remaining power supply device, the display can be performed without changing the original design, and a highly reliable information display device is realized.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 3 is a block diagram of an information display device according to a third embodiment of the present invention, where the same or equivalent parts as those described above (FIG. 1) are denoted by the same reference numerals. In FIG. 3, each of the display dot circuits 21 to 2n is L
It comprises an ED 31, a transistor 32 and a storage circuit 33, does not have an AND gate 34 as compared with FIGS. 1 and 2, and does not output the control signal CNT from the control unit 1. Now, when a failure occurs in the power supply device 11 and the failure signal S1 changes to “H” level, the control unit 1 detects this and calculates and compares the supplied power supply capacity and the required power supply capacity as described above. .

Here, when the required power supply capacity is larger than the supply power supply capacity, it is determined that the other power supply devices 12 to 14 are overloaded when the current symbol display is continued. The information contained in the current symbol is newly configured with a symbol having a smaller required power supply capacity, for example, a symbol with a small number of characters or a small character, and is output to the storage circuit 33 of each of the display dot circuits 21 to 2n by the display data D. As a result, as shown in the section T3 of FIG. 4, a part of the display data D, which has been lit up ("H" level) until now, is turned off ("L" level).
1 is stopped.

FIG. 7 shows a symbol display example newly constructed in response to a failure of the power supply unit. The size of the characters is smaller than that of FIG. 6B and the number of characters is reduced. Have been. In this case, a simple and low lighting rate symbol is provided in the control unit 1 in advance in correspondence with the initial important symbol, for example, characters such as "accident", "fire", "no traffic" or "no entry". In addition, a symbol having a low lighting rate corresponding to the symbol currently displayed may be selected and displayed according to the failure of the power supply device, and an auxiliary display such as “in a tunnel” indicating a point may be relatively displayed. It may be displayed in small characters.

As described above, when the required power supply capacity is larger than the supply power supply capacity, a design including the initial information and having a smaller required power supply capacity is newly constructed and the display is switched. Therefore, even if a failure occurs in any of the power supply devices, it is possible to retain and display the gist of the information content included in the original symbol with a simpler control and configuration, and to provide a highly reliable information display device. Is realized.

Next, a fourth embodiment of the present invention will be described with reference to FIG. In the above description, when any one of the power supply devices has a failure, the respective power saving methods are used to continue the display based on the power supply capacity that can be supplied from the remaining power supply devices. May be performed in order according to a predetermined criterion instead of being performed individually. FIG. 5 shows a control unit 1 in the case where the above-described power saving methods are combined and implemented.
Is a flowchart showing the processing procedure in the case where the order of execution of the processing is based on the visibility to the user as “display stop of graphic symbols”, “reduction in duty ratio”, “switching to display with low lighting rate” It is what it was.

When a failure occurs in any one of the power supply devices 11 to 14, one of the corresponding failure signals S1 to S4 becomes "H" level, and the control unit 1 responds to changes in these failure signals S1 to S4. In response, the processing shown in the flowchart of FIG. 5 is started. First, calculate the required power supply capacity required for display from the lighting rate for the current symbol,
The power supply capacity that can be supplied by the remaining power supply device is calculated, and the two are compared (step 51). If the required power supply capacity is smaller than the supply power supply capacity (step 5
1: YES), it is determined that the current symbol can be displayed without imposing an overload on the remaining power supply devices, and the process ends without performing the power saving process.

On the other hand, if the required power supply capacity is larger than the supply power supply capacity (step 51: NO), it is determined whether or not a graphic symbol is displayed in the current symbol (step 52). (Step 52: Y
ES), the display of graphic symbols is stopped as the first power saving process (step 53). In this case, when the display area of the graphic symbol is fixed, the display of only the display dot circuits corresponding to the graphic symbol display area is stopped by the dedicated control signal CNT as shown in FIG. Alternatively, when the position or size of the graphic symbol display area is changed, the control signal CNT may be selectively output only to the corresponding display dot circuit to stop the display. New display data D from which only graphic symbols have been deleted may be output to the storage circuits 33 of the display dot circuits 21 to 2n.

Subsequently, the required power supply capacity corresponding to the symbol from which the graphic symbol has disappeared is calculated and compared with the supplied power supply capacity (step 54). If the required power supply capacity is smaller than the supplied power supply capacity (step 54: YES), it is determined that the symbol in which the graphic symbol has disappeared can be displayed without imposing an overload on the remaining power supply devices, and the process ends without performing further power saving processing. On the other hand, if the required power supply capacity is larger than the supply power supply capacity (step 54: NO), the drive current of each LED 31 is suppressed by reducing the duty ratio of the control signal CNT to a predetermined value based on visibility (step 54). 55).

Further, the required power capacity corresponding to the power saving state based on the duty ratio is calculated and compared with the supplied power capacity (step 56). If the required power capacity is smaller than the supplied power capacity (step 56: YES). Then, it is determined that the symbol can be displayed based on the power saving state based on the duty ratio without imposing an overload on the remaining power supply devices, and the process ends without performing further power saving processing. On the other hand, if the required power supply capacity is larger than the supply power supply capacity (step 56:
NO), the display is switched to a new display with a lower lighting rate by changing the number of characters or the size of the characters (step 57).

Further, the required power capacity corresponding to the new display having a low lighting rate is calculated and compared with the supplied power capacity (step 58). If the required power capacity is smaller than the supplied power capacity (step 58: YES), it is determined that a symbol having a low lighting rate can be displayed without imposing an overload on the remaining power supply devices, and the process ends without performing further power saving processing. On the other hand, if the required power supply capacity is larger than the supply power supply capacity (step 58: NO), all displays are stopped to avoid a secondary disaster due to overload on the remaining power supply units (step 59).

As described above, by executing the power saving process in accordance with a predetermined standard, even if a power supply unit has a failure condition, for example, a plurality of power supply units have failed, the control unit controls each power saving unit in an order based on the predetermined standard. It is possible to sequentially implement more appropriate power saving means according to the magnitude and progress of the failure, and in particular, by implementing the power saving means in the order in which the reduction in the visibility of the displayed content due to the implementation is small, The display with higher visibility is continued at the initial failure, and an information display device with higher reliability can be realized.

The case where the order in which the power saving processing is performed is determined based on the visibility of the user has been described. This makes it possible to ensure safety. In addition, the power saving processing may be performed in an order determined by a criterion according to the content of the displayed symbol.
As shown in FIG. 7A, when the original symbol includes a graphic symbol or an omissible character, the graphic symbol is preferentially turned off, and as shown in FIG. When many characters are not included, more appropriate power saving processing can be performed by giving priority to the power saving processing by changing the duty ratio.

In the above description, the case where an LED is used as a display element,
Although the case where one is provided has been described, the present invention is not limited to this. Even when another display element is used or the number of power supply devices is different, the same operation and effect as described above can be obtained.

Further, L capable of multicolor display as a display element
ED, for example, an LED having red and yellow-green monochromatic light-emitting portions
When using a power supply device for each color, or when a power supply device is provided for each color, It is possible to carry out the combination in any manner, and it is also possible to switch and display as a display with a low lighting rate by replacing the orange light emitting portion by simultaneous light emission of both colors in the design with any single color light emission, Alternatively, the display may be continued by displaying in one of the single colors supplied with power.

[0038]

As described above, in the information display device according to the present invention, when a failure occurs in the information display device, a plurality of power supply devices for outputting a predetermined failure signal are connected in parallel. In response to the failure signal from the power supply device, the control unit compares the required power supply capacity required to display the current symbol with the supply power supply capacity that can be supplied from each of the remaining power supply devices. If the power supply capacity is exceeded, the power supply capacity consumed by the display element is reduced, so even if a failure occurs in any of the power supply units, the display is continued by the remaining power supply unit and the initial information The contents can be accurately displayed, and a highly reliable information display device can be realized.

Further, a drive control means for controlling the drive of each display element constituting the whole or a part of the display surface based on a predetermined control signal is provided, and when the required power supply capacity exceeds the supply power supply capacity, Since the driving of each display element constituting a part of the display surface is stopped by the control signal from the control unit, the display can be continued with a simple configuration. Further, drive control means for controlling the drive of each display element constituting all or a part of the display surface based on a predetermined control signal is provided, and when the required power supply capacity exceeds the supply power supply capacity, By outputting a control signal having a predetermined duty ratio, each display element constituting all or a part of the display surface is intermittently driven, so that display is continued without changing the original symbol. It becomes possible.

When the required power supply capacity exceeds the supply power supply capacity, the control unit controls each display element based on display data indicating a new symbol whose required power supply capacity is smaller than the current symbol. Therefore, it is possible to hold and display the gist of the information content included in the initial symbol with a simpler control and configuration. Also, a plurality of power saving means for suppressing the power capacity consumed by the display element is provided, and when the required power capacity exceeds the supply power capacity,
The control unit performs each power saving means in an order based on a predetermined standard, so that more appropriate power saving means can be sequentially implemented according to the magnitude and progress of the failure, and particularly, the visibility of the display contents by the implementation. By executing the power saving means in the order of the decrease in the power consumption, the display with higher visibility is continued at the initial failure, and the information display device with higher reliability can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram of an information display device according to an embodiment of the present invention.

FIG. 2 is a block diagram of an information display device according to another embodiment of the present invention.

FIG. 3 is a block diagram of an information display device according to another embodiment of the present invention.

FIG. 4 is a timing chart showing signals of respective parts of the information display device according to the present invention.

FIG. 5 is a flowchart illustrating a processing procedure when a plurality of power saving methods are combined and executed.

FIG. 6 is an explanatory diagram showing a symbol display example according to the present invention.

FIG. 7 is an explanatory diagram showing another symbol display example according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Control part, 2 ... Display part, 11-14 ... Power supply device, 21
２2n: display dot circuit, 31: LED, 32: transistor, 33: storage circuit, 34: AND gate (drive control means), D: display data, CNT: control signal, S1
S4: Failure signal.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G09G 3/20 670 G09G 3/20 670N 5/00 550 5/00 550A

Claims (6)

(57) [Claims] An information display for displaying various kinds of information by dot spelling by driving display elements arranged on a display surface in a matrix in a vertical and horizontal matrix based on display data indicating a pattern composed of characters and graphic symbols. A plurality of power supply devices connected in parallel to each other to supply power to the display elements, and to output a predetermined failure signal when a failure occurs in the device; In response to a failure signal from the power supply device, a required power supply capacity required for displaying a current symbol is compared with a supply power supply capacity that can be supplied from each of the remaining power supply devices. An information display device comprising: a control unit configured to reduce a power supply capacity consumed by the display element when the power supply capacity is exceeded. 2. The information display device according to claim 1, further comprising: a drive control unit configured to control driving of each of the display elements configuring all or a part of the display surface based on a control signal, When the required power supply capacity exceeds the supply power supply capacity, by outputting the control signal, the drive of each of the display elements constituting a part of the display surface is stopped. Information display device. 3. The information display device according to claim 1, further comprising: a drive control unit configured to control a drive of each of the display elements forming all or a part of the display surface based on a control signal, When the required power supply capacity exceeds the supply power supply capacity, by outputting the control signal having a predetermined duty ratio, the display elements constituting all or a part of the display surface are intermittently output. An information display device characterized by being driven. 4. The information display device according to claim 1, wherein the control unit is a symbol indicating initial information when the required power supply capacity exceeds the supply power supply capacity, and the required power supply capacity is a current design. An information display device, wherein each of the display elements is driven based on display data indicating fewer new symbols. 5. The information display device according to claim 1, further comprising: a plurality of power saving means for suppressing a power supply capacity consumed by the display element, wherein the control unit controls the power supply capacity to be equal to the supply power. An information display device, wherein when the capacity is exceeded, the power saving means is sequentially executed based on a predetermined standard. 6. The information display device according to claim 5, wherein the control unit executes the power saving means in ascending order of a decrease in visibility of display contents due to the execution of the power saving means. Information display device.