JPH01273922A - Liquid crystal display device for electric range - Google Patents

Abstract

PURPOSE:To eliminate the necessity of illuminating a liquid crystal element all the time but make it possible to illuminate only it is required by adding a LED control device which controls the lighting and unlighting a group of LED's for illuminating liquid crystal display elements. CONSTITUTION:A LED control device 23 is constituted with a transistor 23a and resistors 23b and 23c. When the program of a display action is executed, LED's 11-18 are lighted, and next a display data is outputted to a liquid crystal display element (LCD) 19 to light it. And, by providing a control a device 26 for heater energizing which is controlled to open and close while a microcomputer 22 is in the energization control mode, LED's 11-18 are lighted and the LCD is lighted while the mode is the energization control mode. While not in the energization control mode it is possible to unlight the LED's 11-18. Further, a frame section 21 for holding the LCD 19 and diffusion plates and for shielding light is provided with partition plates 27 to divide it into four chambers, and by means of a control device 28 for LED which can light and unlight independently four kinds of two LED's it is possible also to light only the LED which corresponds to the section which is displayed on LED 19.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a liquid crystal display device for an electric range used in general households.

BACKGROUND OF THE INVENTION Conventional liquid crystal display devices of this type have used reflective liquid crystal hydrogen atoms. However, since this liquid crystal display element does not emit light, various lighting devices are used. An example of a liquid crystal display device having this type of illumination is shown in FIG.

In this FIG. 9, 1 is a light emitting board, and this light emitting board 1
In this method, a chip-type LED is mounted on a substrate, and the chip-type LED is connected by a pattern and a bonding wire. 2 is a diffusion plate for diffusing light from the light emitting substrate 1, 3 is a liquid crystal display element, and 4 is a printed circuit board on which electronic components are mounted. In this configuration, the liquid crystal display element 3 receives light from the LED mounted on the light emitting substrate 1 from behind through the diffuser plate 2, so that it can be seen even in a dark place. In addition, these lighting devices
When the operation starts, the entire surface of the liquid crystal display device is illuminated.

Problems to be Solved by the Invention However, in the conventional configuration described above, when attempting to display various operating modes using a large liquid crystal display element, the entire surface is illuminated as soon as the power is turned on. Unfortunately, when a liquid crystal display element is used partially, the display may be difficult to read. Another problem was that because the entire surface of the liquid crystal display was always lit, a large amount of current was consumed.

An object of the present invention is to provide a liquid crystal display device for an electric range that solves these problems.

Means for Solving the Problems In order to solve the above problems, the liquid crystal display device for an electric range of the present invention controls the lighting and extinguishing of a group of LEDs for illuminating the liquid crystal display element arranged on the back surface of the liquid crystal display element. It has an LED control device added.

Further, the LED control device automatically lights up the LED group only when the heater energization control device that controls energization to the heater is in the energization control state, or when some display is being output to the liquid crystal display element. The configuration is such that only the LED group is automatically turned on.

Further, the LED control device is configured to independently control each of the plurality of divided LEDs, and the LED control device is configured to independently control each of the divided LEDs, and the LED control device is configured to independently control each of the divided LEDs, and
The configuration is such that only the light is turned on.

Further, when the content displayed on the liquid crystal display element is a warning message when an abnormality is detected, the LED control device causes the entire LED group to blink at a constant cycle, or causes the divided LEDs to blink alternately. It is configured as follows.

Function In the liquid crystal display device configured as described above, when nothing is displayed on the liquid crystal display element in standby mode, such as immediately after the power is turned on, the LED group turns off and the heater starts energizing. When the mode shifts to the energization control mode, the LED group lights up until this mode ends, and when the energization control mode ends, the LED group also turns off. Also, since the LED group is off unless something is displayed on the LCD, it is necessary to illuminate the LCD when the power is on but nothing is displayed on the LCD. In the absence of this, unnecessary current will not flow, and it will be visually clear whether the device is in an operating state or a standby state.

Furthermore, the LED control device is configured to independently control each of the divided LEDs, and is configured to light only the LED corresponding to the portion displayed on the liquid crystal display element. When a pictogram is displayed on a part of the liquid crystal display element, only that pictogram can be highlighted by lighting the LED, and as a result, it is possible to more clearly recognize what mode is currently in progress. It is something.

In addition, when displaying a message or the like when an abnormality is detected on the liquid crystal display element, the entire illumination of the liquid crystal display element is blinked, and the LEDs divided into multiple parts are blinked alternately, so the user can It is possible to call for more attention to the situation.

Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. FIG. 1(a) shows the configuration of a liquid crystal display device in an embodiment of the present invention, in which 1Q is a printed circuit board, 11 to
18 is a diode type L arranged on the printed circuit board 1o.
ED, 19 is a transmission type liquid crystal display element, 19a, 19b
, 19c, and 19d are displayed. 20 is the LED1
A light diffusing plate 21 is disposed between the liquid crystal display element 19 and the liquid crystal display element 19, and is a frame portion for holding the liquid crystal display element 19 and the diffusing plate 20 and blocking light.

FIG. 1(b) shows a circuit diagram of the same liquid crystal display device, where 22 is a microcomputer and 123 is an LED composed of a transistor 23a and resistors 2sb and 23C.
fli11# device, 24 is AC power supply, 25 is heater,
Reference numeral 28 denotes a heater energization control device composed of a relay coil 28a and an IJ relay point 26b, and this heater energization control bag @26 is controlled to open and close when the operating mode of the microcomputer 22 is in the energization control mode.

The operation of the liquid crystal display device for an electric range constructed as described above will now be described based on the flowcharts of FIGS. 2 to 4 showing the display operation.

In the embodiment shown in FIG. 2, when the display operation program is executed, the LEDs 1 to 18 are turned on in step 101, and the display data is outputted to the liquid crystal display element (LCD) 19 in the next step 102, and the LEDs are turned on. It looks like this. In the embodiment shown in FIG. 3, when the display operation program is executed, if the current mode is the energization control mode in step 103, the LEDs 11 to 18 are turned on in step 101, and the liquid crystal display element ( LCD) 19 is turned on. If it is not the energization control mode in step 103, the process proceeds to step 104, and the LEDs 11 to 18
Turn off the light and exit.

In the embodiment shown in FIG. 4, in step 106, the liquid crystal display element (
If there is data to be output to LCD) 19, step 10
1, the I and EDs 11 to 18 are turned on, and in step 102, the liquid crystal display element (I, CD) 19 is turned on. Further, if there is no data to be output to the liquid crystal display element (LCD) in step 105, the process proceeds to step 104.
The LEDs 11 to 18 are turned off and the process ends.

FIG. 6 fal is a front view showing the frame 21 shown in FIG. 1(a) divided into four rooms by providing three partition plates 27, and shows the positional relationship with the LEDs 1 to 18. ing. Figure 5 (BL is the L that allows the four types of two LEDs surrounded by each room mentioned above to be turned on and off independently.
EL) shows a circuit diagram of the control device 28.

The operation of the above configuration will now be described based on the flowcharts shown in FIGS. 6 to 8.

In the flowchart of FIG. 6, first, step 1
If there is data to be displayed on the liquid crystal display element (LCD) 19 in step 05, the process proceeds to the next step 106, and the liquid crystal display element (
If the output data of the LCD (LCD) 19 is output to the position 19a on the liquid crystal display (LCD) 19 shown in FIG.
19(7) 19a(7) position LEDll, 12 is turned on; otherwise, in step 108, LEDll is turned on.

12 is turned off. Next, the process proceeds to step 109, where it is determined whether the output position of the liquid crystal display element (LCD) 1s is at the position 19b, and if it is at the position 19b,
In step 110, LEDs 13 and 14 are turned on, and if not, in step 111, LEDs 13 and 14 are turned off. Similarly, in steps 112 to 117, when the output position of the liquid crystal display element (LCD) 19 is 19c,
When EDl5.16 is lit and the output position is 19d, it is LE.
Turn on Dl7.18. Moreover, when there is no output data at each output position, the LEDs 11 to 18 corresponding to the respective output positions 19a to 19d are turned off. After passing step 117, display data of a liquid crystal display element (LCD) is outputted in step 102. Still step 1
If there is no display output data of the liquid crystal display element (LCD) in step 05, the LEDs 11 to 18 are turned off in step 118, and the process ends.

In the flowchart of FIG. 7, if it is determined in step 119 that the abnormal mode is present, the process proceeds to step 120, where all the liquid crystal display elements (LCDs) 19 are turned on, and in the next step 121, the LEDs 11 to 18 are turned on for one second. And in step 122, the light is turned off for one second. Next step 11
Return to step 9 and repeat step 12o until you are no longer in abnormal mode.
Repeat steps 122 to 122. On the other hand, if it is determined in step 119 that the mode is not abnormal, the process ends.

In the flowchart of FIG. 8, if the abnormal mode is determined in step 119, the liquid crystal display element (LCD) is
) 19, and in step 123 the LE
Light up only Dll and 12 for 1 second, and other 0LED13
~18 lights out.

Next, in step 124, turn on LEDl 3.14 for 1 second, and turn on the other LEDl, 12,1es.

Lights out on 16.17.18. Similarly, in step 126, only the LEDs 15 and 16 are turned on, and in step 12
In e, only the LEDs 17 and 18+7) are turned on for one second, and the picture display sections 19a, 19b, 19c, and 19d of the liquid crystal display element (LCD) 19 are sequentially illuminated as a whole. Then, in step 119, if it is not the abnormality detection mode, the process ends.

Effects of the Invention As is clear from the description of the above embodiments, according to the present invention,
0 (1) Since it is equipped with an LED control device that controls turning on and off of the LED for illuminating the liquid crystal display element, it can be used without constantly illuminating the liquid crystal display element. It can be illuminated only at certain times, and by controlling the illumination, it can be used not only to illuminate the liquid crystal display element but also as a means of transmitting information about the status of the equipment.

(2) The LED control device lights up the LED only when the heater energization control device, which controls the energization of the heater, is in the energization control state, so the user can visually see that it is in the energization control mode. You can clearly convey the message. Additionally, the LED is turned on only when some kind of display is output on the liquid crystal display element, so the LED is turned off when nothing is displayed on the liquid crystal display element, such as in standby mode. As a result, it is possible to communicate that the device is currently in standby mode, with no operation, and when there is no need to illuminate, the LED
Since the light is turned off, the current load on the circuit power supply is also reduced.

(3) The LED control device is configured to independently control each of the divided LEDs, and is configured to light only the LED corresponding to the portion displayed on the liquid crystal display element. Therefore, even if only a portion of a small pictogram is displayed on a device with a wide display area, such as a large liquid crystal display, only the LEDs in the vicinity will light up, illuminating the pictogram display, resulting in an extremely becomes easier to recognize.

(2) Since the LED control device blinks the LED group during the abnormal mode, the abnormal state can be clearly recognized even from a distance where the liquid crystal display element is difficult to see. Furthermore, in the abnormal mode, the LED divided into multiple parts is made to alternately flash one page after another, so the user can be more reliably warned of an abnormal state. be.

[Brief explanation of the drawing]

FIG. 1(a) is an exploded perspective view of a liquid crystal display device for an electric range showing an embodiment of the present invention, FIG. 1(b) is an electric circuit diagram of the same, and FIGS. 2 to 4 are the same liquid crystal display device. 6(a) is a partial front view of the same liquid crystal display device, FIG. 6(b) is an electric circuit diagram of the LED control device in the same liquid crystal display device, and FIGS. 6 to 8 are A flowchart showing the operation of the liquid crystal display device, and FIG. 9 is an exploded perspective view of a conventional liquid crystal display device. 11-18...LED, 19...Liquid crystal display element, 20...Light diffusion plate, 23.28...
...LED control device, 26 ... heater,
26... Heater energization control device. Name of agent: Patent attorney Toshio Nakao and 1 other person
~tθ-・-LED Fig. 5 28-L E D control device Fig. 6 Fig. 7 Fig. 8

Claims (6)

[Claims] (1) A transmissive liquid crystal display element, a group of LEDs for illuminating the liquid crystal display element disposed on the back side of the liquid crystal display element, and a light diffusion plate disposed between the liquid crystal display element and the LED group. and an LED control device that controls turning on and off of the LED group. (2) The heater energization control device according to claim 1, further comprising a heater energization control device that controls energization to the heater, and the LED control device is configured to automatically light up the LED group only when the heater energization control device is in the energization control state. LCD display device for electric range. (3) A liquid crystal display device for an electric range according to claim 1, wherein the LED control device is configured to automatically light up the LED group only when the liquid crystal display element is lit. (4) A claim in which the LED control device is configured to independently control each of the divided LEDs, and to light only the LED corresponding to the portion displayed on the liquid crystal display element. A liquid crystal display device for an electric range according to item 1. (5) When the LED control device detects an abnormality in the control circuit and the heater control element that controls energization to the heater,
2. The liquid crystal display device for an electric range according to claim 1, wherein the entire ED group is configured to blink at a constant period. (6) The electric range according to claim 6, wherein the LED control device is configured to alternately blink the plurality of divided LEDs when an abnormality is detected in the control circuit and the heater control element that controls energization to the heater. LCD display device.