Low-temperature starting liquid crystal display screen

Abstract

The utility model relates to the technical field of display screens, and particularly discloses a low-temperature starting liquid crystal display screen, which comprises a backlight module, a liquid crystal display (LCD) screen and a liquid crystal display screen, the heating film is positioned between the LCD display screen and the backlight module, and one end of the heating film is connected with a temperature control circuit capable of performing constant temperature control on the temperature of the heating film; the temperature sensing module is installed on the LCD display screen and connected with the control circuit, the temperature sensing module is matched with the temperature control circuit, the heating film is triggered by the temperature sensing module to heat the LCD display screen in a low-temperature environment through the temperature sensing module, the phenomenon of water mist on the LCD display screen is avoided, and the LCD display screen is protected from being damaged. And after heating is completed, constant-temperature control is conducted on the heating film through the temperature control circuit, so that the LCD display screen has a certain heat preservation function, the LCD display screen can conduct normal display, and the use stability of the display screen in the low-temperature environment is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of display screens, in particular to a low-temperature started liquid crystal display screen. Background Art

[0002] Liquid crystal display is a flat display device that uses liquid crystal materials to display text, graphics, images and videos. Liquid crystal display is usually composed of liquid crystal layer, glass substrate, polarizer, light source and other parts. When current passes through the liquid crystal layer, the liquid crystal molecules will be arranged according to the different electric fields, thereby changing the degree of light transmission, and then displaying different images or texts. With the needs of people's use, the liquid crystal display still needs to be started in a low temperature environment. In order to ensure that the liquid crystal display can work in a low temperature environment, a low temperature start display needs to be designed.

[0003] For example, the Chinese patent document application number is 202222755442.X, which discloses a low-temperature start display screen, including a fixed shell, a temperature control probe is provided on the inner wall of one end of the fixed shell, a liquid crystal display screen is provided on the top of the fixed shell, a control panel is provided on one side of the top of the fixed shell, a shielding glass is provided on the other side of the top of the fixed shell, and a heating film is provided on the bottom of the fixed shell. The utility model uses the arrangement of the heating film and the shielding glass. When the temperature control probe detects that the surrounding environment is lower than -25°C, the single-chip microcomputer controls the power supply relay to operate, so that the heating film can heat the liquid crystal display screen, which can improve the adaptability of the display screen, so that the display screen can work stably under extreme low temperature conditions. When the glass is fogged, the control panel heats the shielding glass to defog, so that the display screen can work stably in environments with different temperatures.

[0004] However, it is not convenient to keep the heating film warm after the above-mentioned LCD screen is heated, so that once the heating film stops heating, the temperature of the heating film will drop, thereby affecting the stability of the LCD screen when used in a low temperature environment. Therefore, we need to propose a low-temperature start-up LCD screen to solve the above-mentioned problems. Utility Model Content

[0005] The purpose of the utility model is to provide a low-temperature start-up liquid crystal display screen, so that the LCD display screen has a certain heat preservation function, the LCD display screen can display normally, and the stability of the display screen when used in a low-temperature environment is improved to solve the problems raised in the background technology.

[0006] To achieve the above object, the utility model provides the following technical solution: a low temperature start-up liquid crystal display screen, comprising: a backlight module, one side of which is provided with an LCD display screen;

[0007] A heating film located between the LCD display screen and the backlight module, one end of the heating film being connected to a temperature control circuit capable of performing constant temperature control on the temperature of the heating film;

[0008] A driving circuit for driving the backlight module to start and stop, one end of the driving circuit is connected to a control circuit, and one end of the control circuit is connected to the heating film through a wire;

[0009] A temperature sensing module is installed on the LCD display screen, and the temperature sensing module is connected to a control circuit.

[0010] Preferably, the backlight module is composed of a plurality of parallel-connected LED light groups, each of which includes a plurality of series-connected LED lights, and both ends of each LED light group are connected to a driving circuit.

[0011] Preferably, the driving circuit includes a driving chip U1, a diode D1 is connected to the Vout end of the driving chip U1, one end of the diode D1 is connected to the inductor L1, one end of the inductor L1 is connected to the ground capacitor C1, the Vin of the driving chip U1 is connected in parallel with a resistor R6 and a ground capacitor C3, and the RT end of the driving chip U1 is connected to the ground resistor R1.

[0012] Preferably, the temperature sensing module includes a thermistor R with one end grounded NTC , the thermistor R NTC The other end is connected to the high temperature environment resistor R HOT , the high temperature environment resistance R HOT With thermistor R NTC The connection end is connected to the driver chip U1, and the high temperature environment resistor R HOT The other end is connected to a resistor R8, one end of which is connected to the T of the driver chip U1. SET The connecting end of the resistor R8 and the driving chip U1 is connected to a ground resistor R7.

[0013] Preferably, the temperature control circuit includes a sensing chip U3 and a transformer T1 connected to a 220V voltage on one side, a rectifier BD1 is connected to the other side of the transformer T1, a capacitor C11 and a diode VD5, a resistor R11 and a transistor VT1 are connected in parallel at one end of the rectifier BD1, a resistor R22 is connected to the base of the transistor VT1, one end of the resistor R22 is connected to the 7th pin of the sensing chip U3, and the 2nd pin of the sensing chip U3 is connected to the potentiometer RP1, and the potentiometer RP1 is One end is connected to a potentiometer RP2, one end of the potentiometer RP2 is connected to pin 3 of the sensing chip U3, the other end of the potentiometer RP2 is connected in parallel to a diode VD3, a resistor R44 and a transistor VT2 arranged in series, and a resistor R66 and a transistor VT3 arranged in series, the base of the transistor VT2 is connected to pin 6 of the sensing chip U3 through a resistor R33, the collector of the transistor VT3 is connected to a temperature rise load unit, and the base of the transistor VT3 is connected to the sensing chip U3 through a resistor R55.

[0014] Preferably, the temperature rising load unit includes a diode VD7, one end of the diode VD7 is connected to a transistor VS, one end of the transistor VS is connected to one side of the transformer T1 through a resistor Rf, the connecting end of the transistor VS and the resistor Rf is connected to a resistor R77 and a capacitor C22 arranged in series, and one end of the capacitor C22 is respectively connected to the other end of the transistor VS and the emitter of the transistor VT2.

[0015] Preferably, the control circuit includes a microcontroller chip U5, pin 18 of the microcontroller chip U5 is connected in parallel with a capacitor C10 to ground and a capacitor C20 to ground, and a crystal oscillator Y1 is connected between the non-grounded pins of the capacitor C10 to ground and the capacitor C20 to ground, pin 9 of the microcontroller chip U5 is connected in parallel with a capacitor C22 and a resistor R20, the connecting end of the capacitor C20 and the resistor R20 is connected to a resistor R12, one end of the resistor R12 is connected to a switch S, one end of the switch S is connected to the other end of the capacitor C22, and the microcontroller chip U5 is respectively connected with a connector J1 connected to the temperature control circuit, a connector J2 connected to the temperature sensing module, a connector J3 connected to the heating film, and a J5 connected to the drive circuit.

[0016] Compared with the prior art, the beneficial effects of the utility model are:

[0017] 1. The utility model uses the temperature control circuit, heating film, temperature sensing module and control circuit to trigger the heating film to heat the LCD display screen in a low temperature environment, thereby avoiding the occurrence of water mist on the LCD display screen. After the heating is completed, the heating film is controlled at a constant temperature by the temperature control circuit, so that the LCD display screen has a certain heat preservation function, the LCD display screen can display normally, and the stability of the display screen in a low temperature environment is improved.

[0018] 2. The utility model facilitates the control of the LCD display screen to display or turn off through the cooperation of the driving circuit, the backlight module and the control circuit, thereby improving the convenience of using the LCD display screen. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a system block diagram of the utility model;

[0020] Figure 2 This is a connection circuit diagram of the backlight module, driving circuit and temperature sensing module of the utility model;

[0021] Figure 3 This is a circuit diagram of the temperature control circuit of the utility model;

[0022] Figure 4 The utility model is a circuit diagram of the control circuit. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] See also Figure 1-4 The utility model provides a technical solution: a low temperature start-up liquid crystal display screen, comprising: a backlight module, one side of the backlight module is provided with an LCD display screen; Figure 2 As shown, the backlight module is composed of multiple groups of LED lamps connected in parallel, each group of LED lamps includes multiple LED lamps connected in series, and both ends of each group of LED lamps are connected to the driving circuit;

[0025] A heating film located between the LCD display screen and the backlight module, one end of the heating film being connected to a temperature control circuit capable of performing constant temperature control on the temperature of the heating film;

[0026] like Figure 3As shown, the temperature control circuit includes a sensing chip U3 and a transformer T1 connected to a 220V voltage on one side, a rectifier BD1 is connected to the other side of the transformer T1, a capacitor C11 and a diode VD5, a resistor R11 and a transistor VT1 arranged in series are connected at one end of the rectifier BD1 in parallel, a resistor R22 is connected to the base of the transistor VT1, one end of the resistor R22 is connected to pin 7 of the sensing chip U3, a potentiometer RP1 is connected to pin 2 of the sensing chip U3, one end of the potentiometer RP1 is connected to the potentiometer RP2, one end of the potentiometer RP2 is connected to pin 3 of the sensing chip U3, the other end of the potentiometer RP2 is connected in parallel to a diode VD3, a resistor R44 and a transistor VT2 arranged in series, and a resistor R66 and a transistor VT3 arranged in series, the transistor V The base of T2 is connected to the 6th pin of the sensing chip U3 through the resistor R33, the collector of the transistor VT3 is connected to the heating load unit, and the base of the transistor VT3 is connected to the sensing chip U3 through the resistor R55. The temperature threshold of the heating film when the LCD display screen is normally displayed is first set through the sensing chip U3. When the actual temperature of the heating film reaches the threshold, the potentiometer RP1 and the potentiometer RP2 are controlled by the sensing chip U3 to perform constant temperature control, wherein the potentiometer RP1 is the lower limit temperature control, and the potentiometer RP2 is the upper limit temperature control. When the actual temperature of the heating film is lower than the threshold, the heating film is triggered by the heating load unit to heat up, so that the heating film can be kept within a constant temperature range, so that the LCD display screen has a certain heat preservation function, so that the LCD display screen can display normally, and the stability of the display screen when used in a low temperature environment is improved.

[0027] The temperature rise load unit includes a diode VD7, one end of the diode VD7 is connected to a transistor VS, one end of the transistor VS is connected to one side of a transformer T1 through a resistor Rf, the connecting end of the transistor VS and the resistor Rf is connected to a resistor R77 and a capacitor C22 which are arranged in series, one end of the capacitor C22 is respectively connected to the other end of the transistor VS and the emitter of the transistor VT2, so as to trigger the heating film to heat up, so that the heating film can be kept within a constant temperature range, and ensure that the LCD can be displayed and used normally.

[0028] A driving circuit for driving the backlight module to start and stop, one end of the driving circuit is connected to a control circuit, and one end of the control circuit is connected to the heating film through a wire;

[0029] like Figure 2As shown, the driving circuit includes a driving chip U1, a diode D1 is connected to the Vout end of the driving chip U1, one end of the diode D1 is connected to the inductor L1, one end of the inductor L1 is connected to the ground capacitor C1, the Vin of the driving chip U1 is connected in parallel with a resistor R6 and a ground capacitor C3, the RT end of the driving chip U1 is connected to the ground resistor R1, the driving chip U1 is used to drive different LED light groups to start, and the LCD display screen is displayed by starting different LED light groups.

[0030] like Figure 4 As shown, the control circuit includes a microcontroller chip U5, and the 18th pin of the microcontroller chip U5 is connected in parallel with a capacitor C10 to ground and a capacitor C20 to ground, and a crystal oscillator Y1 is connected between the non-grounded pins of the capacitor C10 to ground and the capacitor C20 to ground, and the 9th pin of the microcontroller chip U5 is connected in parallel with a capacitor C22 and a resistor R20, and the connecting end of the capacitor C20 and the resistor R20 is connected with a resistor R12, and one end of the resistor R12 is connected with a switch S, and one end of the switch S is connected to the other end of the capacitor C22, and the microcontroller chip U5 is respectively connected with a connector J1 connected to the temperature control circuit, a connector J2 connected to the temperature sensing module, a connector J3 connected to the heating film, and a J5 connected to the drive circuit, so as to facilitate the coordinated work between the temperature control circuit, the temperature sensing module, the drive circuit and the backlight module through the microcontroller chip U5, so as to ensure that the LCD can be stably turned on and used in a low temperature environment (generally around minus 25°C).

[0031] A temperature sensing module installed on the LCD display screen, wherein the temperature sensing module is connected to a control circuit;

[0032] like Figure 2 As shown, the temperature sensing module includes a thermistor R with one end grounded. NTC , the thermistor R NTC The other end is connected to the high temperature environment resistor R HOT , the high temperature environment resistance R HOT With thermistor R NTC The connection end is connected to the driver chip U1, and the high temperature environment resistor R HOT The other end is connected to a resistor R8, one end of which is connected to the T of the driver chip U1. SET The connection end of the resistor R8 and the driver chip U1 is connected to a ground resistor R7, and the thermistor R NTC The resistance value changes according to the temperature, and the high temperature environment resistance R HOT In order to maintain stable resistance characteristics in a high temperature environment, the thermistor R NTC And high temperature environment resistance R HOTThe characteristic changes are detected by the driver chip U1, which then reads and processes these signals to sense and measure temperature changes.

[0033] During operation, the temperature environment of the LCD display is sensed by the temperature sensing module, and the sensed data is transmitted to the control unit. When the LCD display is started, the control unit starts the heating film to heat the LCD display to avoid water mist on the LCD display. The control unit controls the drive circuit to drive the backlight module to start, so that the LCD display starts normally. After the startup is completed, the heating film is no longer heated, and the heating film is controlled at a constant temperature by the temperature control circuit, so that the LCD display has a certain heat preservation function, so that the LCD display can display normally, and the stability of the display when used in a low temperature environment is improved.

[0034] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Low temperature start-up LCD display, characterized by: include: A backlight module, wherein an LCD display screen is arranged on one side of the backlight module; A heating film located between the LCD display screen and the backlight module, one end of the heating film being connected to a temperature control circuit capable of performing constant temperature control on the temperature of the heating film; A driving circuit for driving the backlight module to start and stop, one end of the driving circuit is connected to a control circuit, and one end of the control circuit is connected to the heating film through a wire; A temperature sensing module is installed on the LCD display screen, and the temperature sensing module is connected to a control circuit.

2. The low temperature start-up liquid crystal display according to claim 1, characterized in that: The backlight module is composed of a plurality of parallel-connected LED light groups, each of which includes a plurality of serially connected LED lights, and both ends of each LED light group are connected to a driving circuit.

3. The low temperature start-up liquid crystal display according to claim 2, characterized in that: The driving circuit includes a driving chip U1, a diode D1 is connected to the Vout end of the driving chip U1, one end of the diode D1 is connected to the inductor L1, one end of the inductor L1 is connected to the ground capacitor C1, the Vin of the driving chip U1 is connected in parallel with a resistor R6 and a ground capacitor C3, and the RT end of the driving chip U1 is connected to the ground resistor R1.

4. The low temperature start-up liquid crystal display according to claim 3, characterized in that: The temperature sensing module includes a thermistor R with one end grounded NTC , the thermistor R NTC The other end is connected to the high temperature environment resistor R HOT , the high temperature environment resistance R HOT With thermistor R NTC The connection end is connected to the driver chip U1, and the high temperature environment resistor R HOT The other end is connected to a resistor R8, one end of which is connected to the T of the driver chip U1. SET The connecting end of the resistor R8 and the driving chip U1 is connected to a ground resistor R7.

5. The low temperature start-up liquid crystal display according to claim 4, characterized in that: The temperature control circuit includes a sensing chip U3 and a transformer T1 connected to a 220V voltage on one side, a rectifier BD1 is connected to the other side of the transformer T1, a capacitor C11 and a diode VD5, a resistor R11 and a transistor VT1 are connected in parallel to one end of the rectifier BD1, a resistor R22 is connected to the base of the transistor VT1, one end of the resistor R22 is connected to the 7th pin of the sensing chip U3, and the 2nd pin of the sensing chip U3 is connected to the potentiometer RP1, one end of the potentiometer RP1 A potentiometer RP2 is connected, one end of the potentiometer RP2 is connected to pin 3 of the sensing chip U3, the other end of the potentiometer RP2 is connected in parallel with a diode VD3, a resistor R44 and a transistor VT2 arranged in series, and a resistor R66 and a transistor VT3 arranged in series, the base of the transistor VT2 is connected to pin 6 of the sensing chip U3 through a resistor R33, the collector of the transistor VT3 is connected to a temperature rise load unit, and the base of the transistor VT3 is connected to the sensing chip U3 through a resistor R55.

6. The low temperature start-up liquid crystal display according to claim 5, characterized in that: The temperature rise load unit includes a diode VD7, one end of the diode VD7 is connected to a transistor VS, one end of the transistor VS is connected to one side of a transformer T1 through a resistor Rf, the connecting end of the transistor VS and the resistor Rf is connected to a resistor R77 and a capacitor C22 arranged in series, and one end of the capacitor C22 is respectively connected to the other end of the transistor VS and the emitter of the transistor VT2.

7. The low temperature start-up liquid crystal display according to claim 6, characterized in that: The control circuit includes a microcontroller chip U5, wherein the 18th pin of the microcontroller chip U5 is connected in parallel with a capacitor C10 to ground and a capacitor C20 to ground, and a crystal oscillator Y1 is connected between the non-grounded pins of the capacitor C10 to ground and the capacitor C20 to ground, and the 9th pin of the microcontroller chip U5 is connected in parallel with a capacitor C22 and a resistor R20, and the connecting end of the capacitor C20 and the resistor R20 is connected with a resistor R12, one end of the resistor R12 is connected with a switch S, and one end of the switch S is connected to the other end of the capacitor C22, and the microcontroller chip U5 is respectively connected with a connector J1 connected to the temperature control circuit, a connector J2 connected to the temperature sensing module, a connector J3 connected to the heating film, and a J5 connected to the drive circuit.

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