JPS5815837B2 - Hiyojisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a display device comprising a display device and a priority determining device, and particularly to an improvement in a display device that performs a plurality of different types of display operations within a limited narrow display space. .

As automatic control devices and automatic monitoring devices have come into widespread use in various fields in recent years, various display devices have become necessary to indicate changes or states in their functional parts.

In general, in order to accurately communicate and display the status of a large number of functional parts, it is suitable to display characters, symbols, or figures (hereinafter simply referred to as characters).

However, a disadvantage of this character display is that it requires a relatively large display space to read the displayed characters.

The character display devices described above cannot be used in most cases where display space is limited.

A display device installed in the driver's seat of a vehicle such as an automobile is known as a notable example of a display space limited.

It is desirable to constantly monitor the status of each functional part of a vehicle even while in the driver's seat, and such a device is already installed in some vehicles as a central vehicle warning system.

In such a warning device, it is desirable to display text in order to clearly indicate the functional section in which an abnormal condition has occurred.

However, as is well known, the driver's seat of a vehicle is equipped with many instruments and other instruments, and it has not been possible to obtain enough display space to accommodate a display device that displays characters in correspondence with the many functional parts.

Therefore, the display device used in the central warning system for a vehicle normally indicates an abnormal location by illuminating a display plate showing each functional section.

This makes it difficult to identify abnormalities, and in particular, reading the characters on a small display plate that is illuminated while the vehicle is running has the disadvantage of actually causing an accident.

Improved display devices suitable for displaying a large number of characters within such a limited display space are known.

This display device includes a display element consisting of a transparent display plate provided with a reflective part corresponding to a desired character and a light source part that irradiates light from the side of the display plate, and a plurality of display elements are arranged in a stacked manner. It consists of two configurations.

According to this improved display device, since a plurality of display elements each having a display function are arranged in a stacked manner, many display functions can be performed even in a limited display space, and it can be used as a centralized warning system for vehicles. It is also suitable as a display device.

Since the display device described above has a plurality of display elements that correspond to each functional part arranged in a stacked manner, if an abnormality occurs in two or more functional parts, the displayed characters will overlap, making it impossible to read the characters. There were drawbacks.

Such a situation occurs when an abnormality occurs in two or more functional units at the same time, or when another abnormality occurs following one preceding warning display.

In view of these conventional problems, a display device has been proposed in which only one of the stacked display elements activates a warning by adding priority to the abnormality detection signals from each functional section. .

In such a display device having a plurality of display elements, an abnormality check of the display element, abnormality detector, and drive circuit is performed by lighting each display element sequentially or simultaneously.

However, turning on the display elements at the same time makes it difficult to distinguish between abnormalities, and it is extremely troublesome to turn on the display elements individually by sequentially operating check switches, etc. Checking the correspondence with the lighting of the display element may also cause misunderstandings.

The present invention has been made in view of the above points, and is a display that can check for abnormalities in the display element, abnormality detector, and drive circuit by automatically applying a check signal when the power is turned on to sequentially turn on the display elements. The purpose is to provide equipment.

The present invention will be described in detail below based on preferred embodiments shown in the drawings.

The structure of the display element forming the display device according to the present invention is the first
The principle is shown in the figure.

In FIG. 1, a display plate 10 is made of a transparent plate such as glass or plastic, and acrylic resin is particularly suitable.

The display board 10 is held at both ends by supports 11, and a display lamp 12 forming a light source is fixedly disposed in a cavity 11a of the support 11.

Although the surface 10a of the display board 10 is a flat surface, it may be a flat surface or a curved surface.

On the back surface 10b of the display panel 10, reflective portions 13 and 14 are formed, each consisting of a conical or hemispherical perforation.

It is preferable that the perforation depth of each reflective part 13, 14 is set within a range of 0.2 to 0.8 mm, for example, when the thickness of the display board 10 is 1 mm.

The irradiated light from the light source section 12 is directed to the display board 1 as shown by the arrow in FIG.
0 from its side.

Since the thickness of the display board 10 is smaller than the measured length of the irradiated light that shines directly onto both surfaces 10a and iob of the display board 10 from the light source section 12, the angle of incidence with respect to both surfaces 10a or 10b is the critical total reflection angle. becomes larger than

As a result, the irradiated light is totally reflected and is not emitted from the display panel 10 to the outside.

On the other hand, the irradiated light hitting the reflecting portions 13, 14 is reflected by the reflecting portions and then emitted from the surface 10a.

Therefore, light emitting parts corresponding to the reflecting parts 13 and 14 appear on the surface 10a of the display panel 10.

As is clear from the above description, if reflective portions are formed in an appropriate arrangement on the back surface 10b of the display body, desired characters or figures can be displayed.

FIG. 2 shows the characters "A J and 1B" appearing on the display board 10.

In FIG. 3, three display elements shown in FIG. 1 are arranged in a stacked manner to provide a display device capable of displaying three different characters.

In FIG. 3, an indicator lamp 12 forming a light source section is attached to a lamp holder 19 fixed to a substrate 40.

Although not shown, an electrical wiring section is incorporated inside the board 40, and an external power supply and control circuit are connected to the light source section through a connector provided at the end of the electrical wiring section.

Since the other two display elements have similar configurations, the same constituent members as those of the first display element shown in FIG. .

Each of the display panels 10, 20, and 30 is provided with a plurality of reflective portions as explained in FIG. 1, forming a character display area.

Therefore, when any light source section is turned on, characters formed on the display board corresponding to that light source section appear.

For example, when the display lamp 22 is turned on, the emitted light reflected by the reflective section within the display panel 20 and emitted from the display panel 20 passes through the transparent display panel 10 and appears outside the display device.

At this time, if the respective reflecting parts provided on the display boards 20 and 10 are installed with their positions slightly shifted with respect to the horizontal or vertical direction of the figure, the light emitted from the display board 20 will be reflected to the display board 10. The light is not reflected by the reflective part and can pass through the display panel 10 as it is.

Characters formed in the character display area of the display board 30 are also displayed in the same manner.

FIG. 4 shows a preferred embodiment of the priority determining circuit according to the present invention.

Of the three display boards shown in FIG. 3, display board 10 corresponds to an important functional section, display board 20 is slightly less important, and display board 30 corresponds to a less important functional section. Assume that you are doing so.

In FIG. 4, one end of the display lamp 12 that illuminates the display panel 10 is connected to the power supply terminal B, and the other end is connected to the collector of the transistor 51.

The emitter of the transistor 51 is grounded, and its base is connected via a diode 50 to an intermediate connection point between a resistor 52 connected in series with a power supply and an abnormality detector 53.

The abnormality detector 53 is provided in the corresponding functional section, and is turned on when the functional section is in a normal state.

Therefore, at this time, the base potential of the transistor 51 is grounded, and the transistor 51 is maintained in an off state, so that the display lamp 12 is turned off.

The display lamp 22 that illuminates the display panel 20 has one end connected to a power source and the other end connected to the collector of a transistor 54.

The emitter of the transistor 54 is grounded, and its base is connected via a diode 55 to an intermediate connection point between a resistor 56 connected in series to the power supply and an abnormality detector 57.The anode of the diode 55 is connected to a diode 58. It is connected to the collector of the transistor 51 via.

The abnormality detector 57 is turned on when the corresponding functional section is normal, and turns off the indicator lamp 22 by keeping the transistor 54 in the off state.

The display lamp 32 that illuminates the display panel 30 has one end connected to a power source and the other end connected to the collector of a transistor 59.

The emitter of the transistor 59 is grounded, and the base thereof is connected via a diode 60 to an intermediate connection point between a resistor 61 connected in series with a power supply and an abnormality detector 62.

The anode of diode 60 is connected to the collector of transistor 51 via diode 63 and to the collector of transistor 54 via diode 64.

The abnormality detector 62 is turned on when the corresponding functional section is normal, and turns off the indicator lamp 32 by keeping the transistor 59 in the off state.

Each of the above-mentioned abnormality detectors 53, 57, and 62 is composed of various switch devices, but when a contact failure occurs at the contact point, each display plate may malfunction due to an increase in the contact resistance.

The diode groups 50, 55, 60 connected to the bases of each transistor 51, 54, 59 are suitable as level shifts to prevent such problems, and even if the contact resistance of the abnormality detector increases to some extent, transistor 5l
54 and 59 from turning on.

The priority determination circuit according to the present invention has the above-mentioned configuration,
The effect will be explained below.

When the abnormality detector 53, which has the highest priority, detects an abnormality in the corresponding functional section and turns off, the transistor 51
Since a base current flows through the base of the transistor 51 and turns on the transistor 51, the indicator lamp 12 is lit to display a warning.

As a result, the base potential of transistors 54 and 59 is limited to the collector potential of transistor 51, which is approximately the ground potential, via diodes 58 and 63, respectively.

Therefore, while the indicator lamp 12 is on, the abnormality detectors 57 and 6
Even if transistor 2 detects an abnormality and turns off, the transistor 54
, 59 are maintained in the off state and do not interfere with the warning effect of the indicator lamp 12.

Since the warning of the indicator lamp 12 indicates an abnormality in a more important functional part than the warnings of the other lamps 22 and 32, there is no need to display other abnormalities.

When the abnormality detector 53 is turned on by eliminating the abnormality in its corresponding functional section, the transistor 51 is turned off and the indicator lamp 12 is turned off.

At the same time, the collector potential of the transistor 51 rises and releases the limiting effect on the other transistors 54 and 59, so if another abnormality detector detects an abnormality and is turned off at that time, the abnormality is detected. The transistor to which the device is connected is turned on and another warning operation is performed.

Regarding the abnormality detector 57, which has the second priority, the on operation of the transistor 54 limits the operation of the transistor 59 due to the same effect.

However, even if the abnormality detector 57 is turned off and the indicator lamp 22 is lit, if the abnormality detector 53 with a higher priority is turned off and the transistor 51 is turned on, the transistor 54 is immediately turned off. The display lamp 22 is turned off, and the display lamp 12 is turned on instead.

Regarding the abnormality detector 62, which has a low priority, the operation of the transistor 59 is always limited by the other transistors 51 and 54, as is clear from the above-mentioned operation, so the indicator lamp is turned off only when only the abnormality detector 62 is turned off. 32 can be lit.

As is clear from the above description, according to the present invention, when any of the abnormality detectors 53, 57, and 62 is turned off, the corresponding high-priority indicator lamp lights up, so that the location of the abnormality can be known. .

In the present invention, furthermore, when any abnormality occurs, it is effective to warn only the fact of the abnormality in order to prevent accidents.

This warning is issued by flashing a warning light or by a buzzer, etc. at the same time as one or more abnormalities occur, and provides a prompt warning to the driver.

The driver is informed of the occurrence of an abnormality by this warning function, and can then be informed of the location of the abnormality by the indicator lamp.

For this purpose, a device consisting of an OR logic circuit and a warning circuit is added in the invention.

That is, an OR logic circuit including a group of diodes connected to each of the abnormality detectors 53, 57, and 62, and a warning circuit that starts a warning operation based on the output of this OR logic circuit are provided.

Further, the signals to the diode group can also be taken out from each transistor 51, 54, 59 which is a drive circuit for the display lamp.

FIG. 5 shows another embodiment of the display device according to the present invention, in which a first display section 70 includes three display panels 7L, 72.73 and three display panels 81.82. 83.

In the case of a display device having a plurality of display sections like this, the arrangement of each display panel is 71.81 in order of importance.

72, 82, 73, and 83 are alternately distributed.

This arrangement eliminates the inconvenience that important functional sections are classified into the same display section and only one of them is alerted.

FIG. 6 shows a circuit in which a conventional check circuit is added to the display device.

The priority determination circuit shown in FIG.
00,200,300°400, priority diode circuit 1
It consists of 50.

The drive circuit 100 includes a transistor 101 and a diode 10
2 and a resistor 103, and at the same time other drive circuit 2
00, 300, 400 are also transistors 201.301.
401, diode 202, 302, 402 and resistor 2
It is composed of 03,303°403.

Display elements 105°205.305, 405 and abnormality detectors 106°206.306, 406 are connected to each drive circuit 100°200.300, 400, respectively, and each drive circuit 100.200.300.400 is connected at once. and is connected to batch IJ-501 via switch 500.

The priority diode circuit 150 includes diodes 151 and 152.
, 153, a circuit including diodes 251, 252, and a diode 351.

The former diodes 151, 152, 153 are in the drive circuit 1
00, the diodes 251 and 252 then give priority to the operation of the drive circuit 200, and the diodes 351 and 252 give priority to the operation of the drive circuit 200.
then prioritizes the operation of drive circuit 300.

The above structure and operation are as described above.

Each of the drive circuits 100, 200, 300, and 400 degrees has a check circuit 600 including a check switch 600.
A is connected.

The check switch 600 has fixed contacts 601, 610, 6
It consists of 20°630.640 and a movable contact 650.

That is, the check circuit 600A connects the movable contact 650 to the battery 501 via the resistor 660 and the switch 500.
and each fixed contact 610, 620゜630.64
0 to each drive circuit 100, 200, 300, 400 transistors 101, 201.

It is configured by connecting to the base of 301.401.

The fixed contact 601 is a contact that keeps the movable contact 650 in the constant position when the check switch 600 is not operated.

In the above configuration, when the check switch 600 is operated to connect the movable contact 650 to the fixed contact 610, the base of the transistor 101 is connected to the battery 501 and the resistor 66
0 and is connected to a high potential.

Therefore, the transistor 101 enters the operating state, and the display element 105 lights up.

This lighting state is formed even when the abnormality detector 106 does not detect an abnormality, that is, when the contacts are closed.

Therefore, in such a lighting state, if the display element 105 does not light up, the display element 105 or the drive circuit 100
It turns out that it is malfunctioning.

Similarly, by sequentially operating the check switch 600 in the direction of the arrow, each drive circuit 200°300.4
00 and display elements 205, 305° and 405 can be checked for abnormalities.

However, the conventional check circuit 600A includes a check switch 600 having a large number of contacts, and therefore its operation is complicated.

In addition, the check switch 600 is more likely to fail due to contact wear.

The embodiment shown below is an improvement on the above points, and the check switch has a single contact configuration, and the check switch 600
The switching function is replaced by the electronic switching action of the check circuit.

FIG. 7 shows a circuit with the addition of an electronic check signal circuit 700.

This check signal circuit 700 has a check switch 701
It is composed of delay switch circuits 710, 720, and 730 and a resistor 740.

The delay switch circuit 710 is composed of a transistor 711, a capacitor 712, and a resistor 713, 714, and similarly, the other delay switch circuits 720, 730 are composed of a transistor 721, 731, a capacitor 722, 732, and a resistor 7.
It is composed of 23°724.733,734.

The order in which each delay switch circuit 710, 720, 730 turns on is delay switch circuit 710, 720, 730.
The order is

That is, each transistor 711.72
Resistor 713.72 connected to the base circuit of 1.731
3.733 and the time constant of the capacitor 712.722.732.

Therefore, first, after the delay switch circuit 710 is turned on, the second delay switch circuit 720 is turned on after a predetermined period of time, and further after a predetermined period of time, the third delay switch circuit 73 is turned on.
0 is turned on.

These on-operation commands are issued by operating the check switch 701.

That is, each of the delay switch circuits 710, 720, 730 is powered by the battery 501 via the check switch 701.

And the collector of transistor 711 is transistor 1
01, and the respective collectors of transistors 721 and 731 are connected to the anodes of diodes 202 and 302.

Along with this connection, backflow prevention diodes 206 and 306 are inserted and connected to the base circuit of the transistor 20L301, respectively.

One end of the resistor 740 is connected to the battery 501 via the check switch 701, and the other end is connected to the anode of the diode 402.

Along with this connection, a diode 406 for preventing backflow is inserted into the base circuit of the transistor 401.

The check switch 701 is constituted by a bushing switch, and is turned on by pressing the button for a predetermined period of time.

By turning on the check switch 701, each delay switch circuit 710, 720, 730 is supplied with power from the battery 501, and each delay switch circuit 710, 720, 730 is supplied with power.
0.730 resistors 714, 720, 734 and resistor 74
The base of each transistor 10L201.301°401 is powered by a battery 501 via a power supply terminal 0.

In the above configuration, it is assumed that the switch 500 is turned on and the battery 501 is in a state of supplying power to each circuit.

A case where the check switch 701 is pressed in this state will be described.

When the check switch 701 is turned on, each delay switch circuit 710, 720, 730 is supplied with power, and at the same time, the base of each transistor 10L20L 301° 401 is supplied with power through the external resistor 714, 724, 734° 740, respectively.

In this state, each of the delay circuits 710, 720, and 730 cannot yet reach the on state because of the capacitors 712, 722, and 732.

However, the transistor 101 is connected to the check switch 701
It turns on at the same time as turning on.

Under the condition that it is in the on state, the other transistor 201
．． 301.401 also satisfies the same requirements, but when the transistor 101 turns on, the bases of the transistors 20.1 and 30L401 are grounded through the diodes 151, 152, and 153 connected to their respective bases. It will be done.

This is because the action of the priority diode circuit 150 also functions in this respect.

Therefore, transistors 201, 301, and 401 remain off.

At this time, the display element 105 is supplied with power by turning on the transistor 101 and enters a lighting state.

This lighting state continues while 1 to 101 are turned on.

Then, when a predetermined period of time has elapsed and the delay switch circuit 710 enters an on state, the base of the transistor 101 is grounded via the transistor 711, and the transistor 101 becomes an off state.

At this time, the display element 105 is turned off, the bases of the other transistors 20L30L401 are removed from the ground, and conditions for turning on are established.

However, when transistor 201 enters the on state, the bases of other transistors 30L401 are grounded through diode 25L252, and transistors 301.
401 maintains the off state.

At this time, the display element 205 is supplied with power by turning on the transistor 201, and is turned on.

This lighting state continues while the transistor 201 is on, that is, until the transistor 721 is turned on.

Similarly, display elements 305 and 405 are transistors 3
The lighting state is established by the formation of the on state at 01.401.

The fourth display element 405 is turned on by the check switch 701
It will last until it is turned on.

FIGS. 8A, B, C, and D show the above operating states.

The leading edges of waveforms A, B, c, and D are generated when the check switch 701 is turned on and each transistor 101.201.301.
Indicates the start of input of the operation signal to 401, waveforms B and C1D
The broken line portion indicates the state where the operation signal is supplied.

The solid line portion of waveform A indicates the ON state of the transistor 101 due to the ON of the check switch 701; the hatched portion inside thereof indicates the lighting state of the display element 105.

Then, as the transistor 711 turns on at the trailing edge of waveform A, the transistor 101 turns off, and at the same time, the next transistor 201 turns on.

The solid line portion of waveform B indicates the on state of this transistor 201, and the diagonal line portion indicates the lighting state of the display element 205.

Similarly, waveforms C and D indicate the ON operation of the transistor 30L401 and the lighting state of the display elements 305 and 405.

As described above, the lighting state of the display element 405 continues until the check switch 701 is turned off, as shown in the waveform.

In the present invention, the check switch 7 shown in FIG.
01 is formed by a timer circuit that applies a check signal for a predetermined time to each delay switch circuit 710, 720, and 730 based on the ON operation of the ignition switch 500.

This timer circuit is shown in FIG. 9 and includes a time constant circuit consisting of a resistor 702 and a capacitor 703.

One end of resistor 702 is connected to battery 501 via ignition switch 500, and an intermediate connection point between resistor 702 and capacitor 703 is connected to the base of transistor 705 via resistor 704.

The collector of transistor 705 is connected to the base of transistor 706 and to ignition switch 500 via resistor 707.

The collector of the transistor 706 is connected to the ignition switch 500 via a relay coil 708, and the relay contact 7 is turned on and off by the relay coil 708.
One end of 09 is connected to the ignition switch 500, and the other end is connected to each delay switch circuit 710.720.7 in FIG.
30 and a resistor 740.

The timer circuit used in the present invention has the above configuration,
Next, its effect will be explained.

When the vehicle engine is stopped, the transistor 705
Since the switch 706 is in the OFF state, the relay contact 709 is opened and no check signal is sent to the delay switch circuit.

When the ignition switch 500 is turned on, the battery voltage is applied to the collector of each transistor 705, 706.

At this time, since the capacitor 703 is not yet charged, the base potential of the transistor 705 does not reach the on-operation voltage, and the transistor 7'05 is kept in the off state.

As a result, the battery voltage is applied to the base of transistor 706, and transistor 706 is turned on.

Therefore, an exciting current flows through relay coil 708, closing relay contact 709, and each delay switch circuit 710.7
A check signal 770 is applied at 20.730.

This check signal 770 is continued while the drive circuit and display element are being checked for abnormalities, and is automatically stopped after all check operations are completed.

That is, the capacitor 703 is gradually charged through the resistor 702, and after a predetermined charging time, the base potential of the transistor 705 is raised to the ON operating voltage.

At this point, the transistor 705 is turned on, and at the same time, the base potential of the transistor 706 falls below the cutoff voltage, so the transistor 706 is turned off.

As a result, the excitation current of relay coil 708 is cut off,
Since the relay contact 709 is opened, the check signal 770
The application of is stopped.

If the time constant of the time constant circuit including the resistor 702 and the capacitor 703 is selected in accordance with a predetermined check operation time, the check signal can be correctly and automatically stopped after all check operations are completed.

As described above, the present invention has the advantage that the check operation is automatically performed when the ignition switch is turned on.

The circuit shown in FIG. 10 is another example of an implementation circuit.

Also in the embodiment shown in FIG. 10, the check switch is located at the ninth
Although it is formed by the timer circuit shown in the figure, it is shown as a check switch 701 to simplify the explanation.

In this circuit, the check signal circuit 700 is replaced with the delay switch circuits 710, 720, 730 shown in FIG.
It is constructed using L771.

Since the other configurations are completely the same as the circuit shown in FIG. 7, the same reference numerals are given to those parts and the explanation thereof will be omitted.

The operation of check signal circuit 700 will be explained below.

When check switch 761 is turned on, transistor 4
An operating voltage is supplied to the base of transistor 40
1 enters the ON operating state.

At this time, the capacitor 771.761.751 at the base of the other transistors 301.201.101 does not reach a predetermined voltage, and each transistor 301.degree. 20L101 remains in an inoperative state.

The display element 405 is turned on by turning on the transistor 401.
first enters the lit state.

Then, when the capacitor 761 is charged to a predetermined voltage,
The transistor 301 is turned on, and the display element 305
becomes lit.

As the transistor 301 turns on, the base of the transistor 401 is grounded via the diode 351, the transistor 401 turns off, and the display element 40
5 is in an off state.

That is, the diode 351 of the priority diode circuit 350 functions in the same manner as in the circuit shown in FIG. 7 above.

Subsequently, when the capacitor 751 is charged to a predetermined voltage, the transistor 201 is turned on, the transistor 301 is turned off, and the display element 205 enters a lighting state instead of the display element 305.

Similarly, the display element 105 then enters the lighting state.

In this case, the time constant determined by each resistor 750, 760°770 and capacitor 751.76L771 is
It goes without saying that the capacitors become larger in the order of 771°, 761.751.

FIGS. 11A, B, and C1D show the above operating states.

Similar to FIG. 8, the solid line portions of waveforms A, B, C, and D represent each transistor 101.201.

301.401, the broken line part shows the input state of the operation signal, and the diagonal line part shows the on state of the display element 105.205.
．． 305.405'o is lit.

That is, the waveform is the same as that of the transistor 401 and the display element 405.
In this case, the waveform C is the transistor 301 and the display element 30
5, waveforms B and A are transistors 201 and 1, respectively.
01 and display element 205°105.

It can be seen that the situation is completely opposite to the case shown in FIG. 8 above.

The leading edge of the waveform A responds to turning on the check switch 701, and the trailing edge of the waveform A responds to turning off the check switch 701.

As described above, according to the present invention, the warning operation is always performed in the order of the functional parts having the highest importance, and it is possible to avoid display characters from overlapping and becoming unreadable.

Furthermore, since warnings that have been suspended due to low priority are continuously retained, a warning is immediately displayed when a high priority abnormality is resolved.

An abnormality check for the display element, the abnormality detector, and the first drive circuit can be performed by automatically turning on the first drive circuit and the display element for a predetermined period of time when the ignition switch is turned on. It is extremely easy to operate.

Furthermore, since the circuit is constructed using a priority determining function that sequentially turns on the display elements, it is extremely economical and can achieve high reliability from a functional point of view.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a schematic configuration of a display element used in the present invention, FIG. 2 is a front view of main parts showing the display state of FIG. 1,
FIG. 3 is a sectional view showing the specific structure of the display device, FIG. 4 is a circuit diagram showing a preferred embodiment of the priority determining circuit used in the present invention, and FIG. 5 is a diagram showing an embodiment of the display device. 6 is a circuit diagram of a display device with a conventional check circuit added thereto, FIG. 7 is a circuit diagram of a display device with a check signal circuit added thereto showing an embodiment of the present invention, and FIG. 8 shows its operation. FIG. 9 is a circuit diagram showing a timer circuit forming a check switch used in the present invention, FIG. 10 is a circuit diagram showing another embodiment, and FIG. 11 is an explanatory diagram showing its operation. 53.57.62.106.206.306. 406... Abnormality detector, 12, 22, 32.1
05°205.305,405...display element,
700... Check signal circuit, 701...
・Check switch.

Claims (1)

[Claims] 1 A plurality of abnormality detectors arranged in each functional part to detect an abnormality in each functional part, and a plurality of display elements provided corresponding to each abnormality detector to display the functional part in which an abnormal state has occurred. and a plurality of drive circuits provided corresponding to a plurality of display elements that receive a detection signal output from the abnormality detector and energize the display element, and a priority order of the detection signal from each abnormality detector. a priority determination circuit that determines and outputs an activation signal to the corresponding drive circuit to put the drive circuit into an operating state; A timer circuit that generates a check signal for confirming the function; and a timer circuit that receives the check signal from the timer circuit and supplies each of the drive circuits with an operating signal that does not match in time at least at one of the rising and falling points of the check signal. 1. A display device comprising: a delay switch circuit that outputs a delay switch circuit; and a check signal circuit including a delay switch circuit.