JPH02159513A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To enable versatility of a display pattern by arranging a plurality of power sources for irradiate a liquid crystal display plate with color lights differing from one another and a selective drive means for altering and selectively driving the light sources to alter and control color of a display screen. CONSTITUTION:A display device 9 is made up of a liquid crystal display plate 12 and a backlight lamp section 14, which is made up of lamps 15-17 of red, yellow and white inserted into a lamp box 13 through a through hole B. Then, a voltage is applied through leads 12a corresponding to a number of liquid crystal elements to make the elements turbid so that transmissivity of light passing therethrough changes to display a character. A CPU reads detection values of electric parts of various sensors and makes a display panel 12 display a code number of an abnormal part determining an abnormality when the values exceed an allowable value. A color corresponding to the abnormal part, for example, red is read out of an ROM to light a lamp 15 to make a screen of a display panel 12, namely, a display device 9 red. Thus, an operator is informed of the occurrence of an abnormality to be handled at emergency.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a liquid crystal display device.

I. Prior Art] A liquid crystal display device using the electro-optic effect performs a predetermined display by converting electrical changes in a liquid crystal display element into changes in transmitted light and reflected light. In other words, light is projected onto the liquid crystal panel to maintain its brightness, and in the liquid crystal element to which a voltage is applied, the transmission angle of the light is changed and becomes darker, and in a transmission type device, this contrast between light and dark is directly displayed, This is visually observed, and further confirmed by being reflected by a reflecting mirror in a reflective device.

This liquid crystal display device has very low power consumption and is therefore widely used in various fields. - For example, in battery-powered industrial vehicles such as battery forklifts, it is used in various display devices including self-diagnosis display devices. The self-diagnosis display device will be briefly described.

That is, the speedometer of the display panel provided in the driver's cab is formed of a liquid crystal display board, and displays the traveling speed of the vehicle according to instructions from the controller, which is normally in the normal mode. When the controller detects an abnormality in an electrical part, it displays the part with a predetermined code number to call the driver's attention.

However, this speedometer merely displays a uniform liquid crystal display of the abnormal area in response to a single color bank light, and does not make the driver aware of the extent to which the abnormality in that area has a negative impact on driving, cargo handling, etc. isn't it. Therefore, even if a serious abnormality occurs that requires the driver to take immediate action,
The driver may not be able to distinguish it from a minor malfunction and may overlook it. For this reason, a failure may occur in the relevant part, or
It may reduce work efficiency.

[Problems to be Solved by the Invention] The above problems result from the fact that current liquid crystal display devices emit light in a single color. Therefore, an object of the present invention is to provide a liquid crystal display device that can be used in various fields including self-diagnosis display devices for industrial vehicles and can diversify display modes by changing and controlling the color of the screen.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a liquid crystal display board and a plurality of light sources that illuminate the display board with light of different colors when displaying the liquid crystal display board. The gist thereof is to provide a selection driving means for selectively changing and driving the plurality of light sources.

[Function] During display on the liquid crystal display, the plurality of light sources are selectively driven by the selection drive means to emit light in different colors, thereby causing the liquid crystal display board to display in different colors.

[Example 1] An example in which the present invention is embodied in a battery forklift truck will be described in detail below with reference to the drawings.

In FIG. 4, the forklift is driven in accordance with the amount and direction of operation of traveling system operating members such as an accelerator lever 1 and a forward/backward lever 2 provided in the driver's cab, and a lift lever 4, a tilt lever 5, etc. The foyer 7 is moved based on the amount of operation of the operating member. In addition, as shown in FIG. 3, 1. Speed indicator 9 on instrument panel 8
, a key switch 10, a mode changeover switch close, etc. are provided.

As shown in FIG. 1, the speed indicator 9 embedded in the instrument panel 8 includes a translucent liquid crystal display plate 12 constituting a screen, and a backlight lamp part disposed in a lamp box 13. It consists of 14. The backlight lamp section 14 is composed of three sets of three lamps inserted into the lamp box 13 from below through the through hole B, and a red lamp 15, a yellow lamp 16, and a white lamp 17 as light sources. There is.

Then, a voltage is applied through the lead wires 12a corresponding to a large number of liquid crystal elements included in the liquid crystal display board 12, causing cloudiness, and as shown in FIGS. 7 and 8, the transmittance of light passing through this changes. The letter C etc. will be displayed. Therefore, the red lamp 15
When it is lit, red light passes through the entire area of the liquid crystal display board 12 except for characters, etc., and the liquid crystal display board 12 is displayed in red.

Similarly, when the yellow lamp 16 or the white lamp 17 is on, the liquid crystal display panel 12 is maintained in the corresponding color by the yellow light or white light.

Next, an electrical configuration for driving the liquid crystal display panel 12 described above will be explained.

As shown in FIG.
It operates based on the operation of O. When the vehicle is running, the CPU I B causes the white lamp 17 to emit light and displays the liquid crystal display panel 12.
The screen is kept white, and the vehicle speed is digitally displayed on the liquid crystal display board 12 of the speed display 9 based on the detection signal of the vehicle speed sensor 22.

The CPU 18 includes a drive system sensor group 24 such as a potentiometer and a limit sensor, which detects the operation amount, operation direction, etc. of the drive system operating member according to a program stored in a read-only memory (ROM) 19 when the vehicle is traveling and cargo handling. The detected values of electrical parts of the traveling system and cargo handling system, including the cargo handling system sensor group 25 that detects the operation amount of the cargo handling system operating members, are read and temporarily stored in a readable and writable memory (RAM) 23. Make me remember.

Further, the ROM 19 stores the code number of each electrical part and the corresponding reference value, and lamps 15 to 17 to be lit when an abnormality occurs in each electrical part.
The colors are stored according to the importance of the electrical parts.

Now, the operation of the CPU 18 will be explained according to the flowchart shown in FIG.

Now, the vehicle is running, and the traveling speed of the vehicle is displayed on the liquid crystal display panel 12 of the speed indicator 9 under the illumination of the white lamp 17 against a white background (FIG. 7). And step S1
(hereinafter, the step is simply referred to as S), the CPU
1B reads the detected values of the electrical parts of the various sensor groups 24, 25, etc., and in S2 reads the reference values of the corresponding sensors from the ROM 19, and compares the detected values with the reference values. Then, in S3, cpU1B determines that there is an abnormality when the difference between the two values exceeds the allowable range, and in S4, the code of the abnormal part is displayed on the liquid crystal display board 12 of the speed indicator 9 instead of displaying the vehicle speed. Display the number (Figure 8).

Next, CPolB outputs 6L of the color corresponding to the abnormal part from the ROM 19, and when it determines that this is red in S5, that is, when an abnormality has occurred in an extremely important electrical part, it lights up the red lamp 15 in S6. and the liquid crystal display board 12
That is, the screen of the speed indicator 9 is rubbed in red ζ. This 6. Second, the driver recognizes that an abnormality has occurred in the vehicle's electrical system that requires emergency response.

If red lighting is not required due to the determination in S5, it is determined in S7 that the color of the wick in the abnormal area is yellow, and the yellow lamp 16 is turned on in S8 to change the speed indicator 9 screen to yellow. to notify that an abnormality has occurred in a relatively important electrical part. Further, when the determination result in S7 is NO, that is, when an abnormality occurs in an electrical part that does not significantly affect the transportation of the vehicle, the white rung 17 is turned on in the SIO.

As mentioned above, by changing the colored light of the light source, it becomes possible to change the color of the liquid crystal display board 12,
A variety of displays are possible. Accordingly, in the self-diagnosis display device of industrial vehicles, CPtJ i B
detects whether or not there is an abnormality in various electrical parts 2. If there is an abnormality, the vehicle speed display on the speed indicator 9 is temporarily stopped, and the corresponding electrical part (◇ importance level, , : the corresponding color is displayed on the background G) Therefore, when the speed indicator 3 is displayed in red due to the lighting of the red lamp 15, for example, the driving stone is activated (this has a serious effect on the operation of the vehicle). It is possible to recognize that there is an abnormality in the electrical parts causing the problem and immediately move on to analysis of the abnormality and repair work.

In this embodiment, a translucent liquid crystal display panel was used, but instead of this, after the light passes through, it is reflected by a reflecting mirror.
! It is also possible to use a reflective display board.

In this embodiment, the liquid crystal display board 12 is adopted to diversify the function of displaying the vehicle's self-diagnosis.・Anomaly analysis is performed by switching the CP (river 8) to the analyzer, and items that require urgent measures are displayed in red, and may be displayed in yellow or white depending on the degree of urgency. can.

Furthermore, when the mode of the CPU 18 is switched, it is also possible to display the color of the liquid crystal board that displays this by selectively lighting the lamps 15 to 17.

Furthermore, any changes may be made without departing from the spirit of the invention, such as being used not only in battery forklifts but also in industrial vehicles, or even for changing the color of bank lights in any liquid crystal display device other than industrial vehicles. It is possible to argue passionately.

[Effects] As detailed above, according to the present invention, the display color can be changed and the display mode can be diversified.

[Brief explanation of the drawing]

FIG. 1 is a sectional view 1 showing a liquid crystal display device, FIG. 2 is a plan view thereof, and FIG. 3 is a plan view showing an instrument panel.
FIG. 4 is a side view showing a battery forklift, FIG. 5 is a block circuit diagram showing the electrical configuration of the present invention, FIG. 6 is a diagram showing the operation of the CPU, coachyard diagram, FIGS. 1 is a schematic plan view of a speed indicator that displays vehicle speed and self-diagnosis, respectively. Liquid crystal display board 12, red lamp 15, yellow lamp 16, and white lamp 17 as light sources, and C as a selection drive device.
PU18゜Patent applicant Toyoda Fish Loom Manufacturing Co., Ltd. Agent Patent attorney On 1) Hiroshi Nobu 1” 1d = 80

Claims (1)

[Scope of Claims] 1. A liquid crystal display board, a plurality of light sources that illuminate the display board with light of different colors when displaying information on the liquid crystal display board, and a selection driving means that selectively drives the plurality of light sources. A liquid crystal display device.