CN217606298U

CN217606298U - Constant temperature equipment, on-vehicle new line display and vehicle

Info

Publication number: CN217606298U
Application number: CN202221055471.9U
Authority: CN
Inventors: 李明坤; 覃寿远; 张英
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2022-04-29
Filing date: 2022-04-29
Publication date: 2022-10-18
Anticipated expiration: 2032-04-29

Abstract

The utility model discloses a constant temperature equipment, on-vehicle new line display and vehicle, constant temperature equipment includes: the temperature adjusting mechanism is used for adjusting the temperature of the heat source; the temperature measuring circuit is used for detecting the actual temperature of the heat source; and the PID controller is respectively connected with the temperature measuring circuit and the temperature regulating mechanism and is used for carrying out PID regulation according to the actual temperature and the target temperature to obtain a control signal and controlling the temperature regulating mechanism to heat or refrigerate according to the control signal so as to stabilize the temperature of the heat source at the target temperature. The constant temperature device can automatically dissipate or refrigerate the heat source according to the actual temperature of the heat source and the preset target temperature, so that the actual temperature of the heat source is accurately and stably kept at the target temperature.

Description

Constant temperature equipment, on-vehicle new line display and vehicle

Technical Field

The utility model relates to an automatic control technology field especially involves a constant temperature equipment, on-vehicle new line display and vehicle.

Background

In recent years, a Head Up Display (HUD) is becoming more and more popular in the market, and it is also becoming more and more important to improve the user experience of the HUD. The vehicle-mounted HUD mainly adopts LCD (Liquid Crystal Display)Liquid crystal display) and DLP (Digital Light Processing) imaging technologies. The LCD imaging technology is low in brightness and the DLP imaging technology is high in brightness, but both imaging technologies have high requirements on the brightness of the source image. Since the ambient brightness is very different between day and night (maximum brightness in day is about 15000 cd/m) ² At night, about 3cd/m ² ) And ambient brightness decides HUD virtual image luminance, and HUD virtual image luminance further decides HUD module light source luminance again, and HUD virtual image luminance and HUD module light source luminance are direct ratio again. It can be seen that on-vehicle HUD is very high to the luminance requirement of source image when daytime work to lead to HUD module calorific capacity very big. Obviously, no matter which kind of imaging technology, all need consider on-vehicle HUD's heat dissipation problem, if the heat can not in time distribute away, will lead to system's work unstable, and even partial device can burn out when serious, and an effectual radiating mode is very important. And in the north winter the ambient temperature is very low, and too low temperature can lead to on-vehicle HUD unable normal work.

In the correlation technique, the method for radiating the vehicle-mounted HUD is mainly improved from the aspects of structure and material, the radiating effect is poor, and the normal work of the vehicle-mounted HUD under the severe environment in winter can not be ensured.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a constant temperature equipment, according to the actual temperature and the target temperature of heat source, dispel the heat or refrigerate to the heat source automatically, make the accurate and stable maintenance of the actual temperature of heat source at the target temperature.

A second object of the present invention is to provide a vehicle-mounted head-up display.

A third object of the present invention is to provide a vehicle.

In order to achieve the above object, an embodiment of a first aspect of the present invention provides a thermostat device, the device includes: the temperature adjusting mechanism is used for adjusting the temperature of the heat source; the temperature measuring circuit is used for detecting the actual temperature of the heat source; and the PID controller is respectively connected with the temperature measuring circuit and the temperature regulating mechanism and is used for carrying out PID regulation according to the actual temperature and the target temperature to obtain a control signal and controlling the temperature regulating mechanism to heat or refrigerate according to the control signal so as to stabilize the temperature of the heat source at the target temperature.

The constant temperature device provided by the embodiment of the utility model has the advantages that the temperature measuring circuit detects the actual temperature of the heat source, the PID controller carries out PID adjustment according to the actual temperature of the heat source and the preset target temperature to output accurate control signals, and when the actual temperature of the heat source is higher than the target temperature, the temperature adjusting mechanism is controlled to refrigerate to radiate the heat source; and when the actual temperature of the heat source is lower than the target temperature, controlling the temperature regulating mechanism to heat so as to heat the heat source. The temperature of the heat source is accurately controlled, so that the heat source is stabilized at the target temperature, and the overheating or overcooling of the heat source is effectively prevented.

In addition, the thermostat device provided by the above embodiment of the present invention may also have the following additional technical features:

in some examples, the temperature measuring circuit includes a first resistor, a second resistor, a third resistor and a thermistor, the first resistor, the second resistor, the thermistor and the third resistor are connected end to form a wheatstone bridge, the first resistor and the second resistor form a first arm of the wheatstone bridge, the third resistor and the thermistor form a second arm of the wheatstone bridge, one end of the first arm connected with the first resistor is connected with a preset power supply, and one end of the first arm connected with the second resistor is grounded; the preset power supply is used for providing reference voltage, the resistance value of the third resistor is equal to the resistance value of the thermistor corresponding to the target temperature, the thermistor is arranged corresponding to the heat source, and the midpoint of the first bridge arm and the midpoint of the second bridge arm are both connected with the PID controller and used for providing a first voltage signal corresponding to the actual temperature and a second voltage signal corresponding to the target temperature for the PID controller.

In some examples, the thermometry circuit further comprises: the first filter capacitor is connected with the thermistor in parallel.

In some examples, the PID controller includes a chopping operational amplifier circuit, a compensation circuit, an integrating operational amplifier circuit, a comparison operational amplifier circuit, and a PWM control circuit; the middle point of the first bridge arm and the middle point of the second bridge arm are respectively and correspondingly connected with the positive phase end and the reverse end of the chopping operational amplifier circuit, the output end of the chopping operational amplifier circuit is connected with the first end of the compensation circuit, the second end of the compensation circuit is connected with the reverse end of the integral operational amplifier circuit, the output end of the integral operational amplifier circuit is connected with the third end of the compensation circuit, the positive end of the integral operational amplifier circuit is grounded, the first input end of the comparison operational amplifier circuit is connected with the output end of the integral operational amplifier circuit, and the second input end of the comparison operational amplifier circuit is connected with the preset power supply; the comparison operational amplifier circuit is used for outputting a control signal for controlling the temperature adjusting mechanism to heat through the PWM control circuit when the voltage output by the integral operational amplifier circuit is greater than the reference voltage, and outputting a control signal for controlling the temperature adjusting mechanism to refrigerate through the PWM control circuit when the voltage output by the integral operational amplifier circuit is less than the reference voltage.

In some examples, the compensation circuit includes a fourth resistor, a first capacitor, a second capacitor, a fifth resistor, a third capacitor, and a sixth resistor, one end of the fifth resistor and one end of the sixth resistor are connected to the first end of the compensation circuit, the other end of the fifth resistor is connected to one end of the third capacitor, the other end of the sixth resistor, one end of the first capacitor, and one end of the second capacitor are connected to the second end of the compensation circuit, the other end of the first capacitor is connected to one end of the fourth resistor, and the other end of the fourth resistor and the other end of the second capacitor are connected to the third end of the compensation circuit.

In some examples, the temperature adjustment mechanism includes a semiconductor refrigeration sheet, the PID controller further includes a driving circuit, the driving circuit includes a first inductor, a first energy storage capacitor, a seventh resistor, a second filter capacitor, a second energy storage capacitor, a second inductor, a first PMOS transistor, a first NMOS transistor, a second PMOS transistor, and a second NMOS transistor, the semiconductor refrigeration sheet is connected between the seventh resistor and the second energy storage capacitor, one end of the first inductor is connected to the drain of the first PMOS transistor and the drain of the first NMOS transistor, the other end of the first inductor is connected to one end of the first energy storage capacitor and one end of the seventh resistor far from the semiconductor refrigeration sheet, the other end of the first energy storage capacitor and one end of the second energy storage capacitor far from the semiconductor refrigeration sheet are both grounded, one end of the second inductor is connected to the drain of the second PMOS transistor and the second NMOS transistor, and the other end of the second inductor is connected to one end of the semiconductor refrigeration sheet connected to the second energy storage capacitor; when the PWM control circuit outputs a control signal for controlling the temperature adjusting mechanism to refrigerate, the first PMOS tube and the second NMOS tube are conducted, and current flows to the ground end through the first PMOS tube, the first inductor, the seventh resistor, the semiconductor refrigerating sheet, the second inductor and the second NMOS tube and forms a BUCK circuit together with the first energy storage capacitor and the second energy storage capacitor; when the PWM control circuit outputs a control signal for controlling the temperature adjusting mechanism to heat, the second PMOS tube and the first NMOS tube are conducted, and current flows to the ground end through the second PMOS tube, the second inductor, the semiconductor refrigeration sheet, the seventh resistor, the first inductor and the first NMOS tube and forms a BUCK circuit with the first energy storage capacitor and the second energy storage capacitor.

In some examples, the PID controller further includes a current sampling operational amplifier circuit and a voltage sampling operational amplifier circuit, the positive phase end of the current sampling operational amplifier circuit is connected to the seventh resistor, the negative phase end of the current sampling operational amplifier circuit is connected to the seventh resistor, the positive phase end of the voltage sampling operational amplifier circuit is connected to the semiconductor cooler, the negative phase end of the voltage sampling operational amplifier circuit is connected to the seventh resistor, the current sampling operational amplifier circuit and the voltage sampling operational amplifier circuit output end are connected to the PWM control circuit.

In some examples, the thermostat device further includes a heat sink disposed corresponding to the semiconductor chilling plate and configured to dissipate heat of the semiconductor chilling plate.

In some examples, the thermostat device further includes a heat dissipation fan, where the heat dissipation fan is disposed corresponding to the semiconductor chilling plate and used for dissipating heat from the semiconductor chilling plate.

In some examples, the thermistor is soldered to a flexible circuit board that is secured at the heat source.

In order to achieve the above object, an embodiment of a second aspect of the present invention provides an on-vehicle head-up display, including display screen, backlight module and the thermostat device as above, wherein, the backlight module is as the heat source, be used for doing the display screen formation of image provides backlight.

In order to achieve the above object, an embodiment of a third aspect of the present invention further provides a vehicle including the on-vehicle head-up display as described above.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

Fig. 1 is a schematic structural view of a thermostat according to an embodiment of the present invention;

fig. 2 is a circuit diagram of a thermostat according to an embodiment of the present invention;

fig. 3 is a circuit diagram of a temperature measuring circuit according to an embodiment of the present invention;

fig. 4 is a circuit diagram of a compensation circuit of an embodiment of the present invention;

fig. 5 is a circuit diagram of a driving circuit according to an embodiment of the present invention;

fig. 6 is a schematic structural view of a temperature adjustment mechanism according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of an on-vehicle head-up display according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a vehicle according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present invention, and should not be construed as limiting the present invention.

For better understanding of the above technical solutions, the thermostat device, the on-board head-up display and the vehicle will be described in detail with reference to fig. 1 to 8 and specific embodiments of the present disclosure.

Fig. 1 is a schematic structural view of a thermostat according to an embodiment of the present invention. As shown in fig. 1, the thermostat device 100 includes a temperature measuring circuit 10, a PID controller 20, and a temperature adjusting mechanism 30. The temperature adjusting mechanism 30 is used for adjusting the temperature of the heat source; the temperature measuring circuit 10 is used for detecting the actual temperature of the heat source; the PID controller 20 is connected with the temperature measuring circuit 10 and the temperature adjusting mechanism 30 respectively, and is used for performing PID adjustment according to the actual temperature and the target temperature to obtain a control signal, and controlling the temperature adjusting mechanism 30 to heat or refrigerate according to the control signal so as to stabilize the temperature of the heat source at the target temperature.

Specifically, the temperature measuring circuit 10 detects the actual temperature of the heat source, the PID controller 20 performs PID adjustment according to the actual temperature of the heat source and a preset target temperature to output an accurate control signal, and controls the temperature adjusting mechanism 30 to refrigerate and dissipate heat from the heat source when the actual temperature of the heat source is higher than the target temperature; when the actual temperature of the heat source is lower than the target temperature, the temperature control mechanism 30 is controlled to heat the heat source. The temperature of the heat source is accurately controlled, so that the heat source is stabilized at the target temperature, and the overheating or overcooling of the heat source is effectively prevented.

Fig. 2 is a circuit diagram of a thermostat according to an embodiment of the present invention.

In some embodiments, as shown in fig. 3, the temperature measuring circuit 10 may include a first resistor R1, a second resistor R2, a third resistor R3, and a thermistor Rt, where the first resistor R1, the second resistor R2, the thermistor Rt, and the third resistor R3 are connected end to form a wheatstone bridge, the first resistor R1 and the second resistor R2 form a first leg of the wheatstone bridge, the third resistor R3 and the thermistor Rt form a second leg of the wheatstone bridge, one end of the first leg connected to the first resistor R1 is connected to the preset power supply Vcc, and one end of the first leg connected to the second resistor R2 is connected to ground; the preset power supply Vcc is used for providing a reference voltage U1, the resistance value of the third resistor R3 is equal to the resistance value of the thermistor Rt corresponding to the target temperature, the thermistor Rt is arranged corresponding to a heat source, and the midpoint of the first bridge arm and the midpoint of the second bridge arm are both connected with the PID controller 20 and used for providing a first voltage signal corresponding to the actual temperature and a second voltage signal corresponding to the target temperature for the PID controller 20.

The thermistor Rt is a sensor resistor, and its resistance value changes with a change in temperature. When the actual temperature of the heat source changes, the resistance value of the thermistor Rt arranged corresponding to the heat source can be caused to change. The resistance value of the thermistor Rt changes to bring about the change of the first voltage signal, so that the change of the actual temperature of the heat source can be known according to the change of the first voltage signal, the heat source is radiated and heated, and the heat source is kept at the target temperature.

For better effect, the temperature measuring circuit 10 may employ a flexible circuit board, and in some embodiments, the thermistor Rt is soldered on the flexible circuit board, and the flexible circuit board is fixed at the heat source. The thermistor Rt may be disposed corresponding to the heat source by soldering the thermistor Rt on the flexible circuit board so as to detect the actual temperature of the heat source.

In this embodiment, the temperature measuring circuit 10 is a wheatstone bridge composed of a first resistor R1, a second resistor R2, a third resistor R3 and a thermistor Rt, the first resistor R1 and the second resistor R2 constitute a first arm of the wheatstone bridge, and the third resistor R3 and the thermistor Rt constitute a second arm of the wheatstone bridge, wherein the two resistors of the first arm have equal resistance values, and the third resistor R3 of the second arm has equal resistance value to the corresponding resistance value of the thermistor Rt when detecting that the heat source is at the target temperature.

Specifically, since the resistances of the first resistor R1, the second resistor R2, and the third resistor R3 are fixed, the resistance of the thermistor Rt changes with a change in an actual temperature of the heat source, the resistance of the thermistor Rt changes, the first voltage signal output by the midpoint of the second arm changes, and the midpoint of the first arm outputs the second voltage signal corresponding to the target temperature.

In this embodiment, the thermistor Rt employs a Negative Temperature Coefficient thermistor (NTC) whose resistance value decreases as the Temperature increases. When the actual temperature of the heat source is reduced, the resistance value of the negative temperature coefficient thermistor is increased, and the voltage value of the first voltage signal is increased; when the actual temperature of the heat source is increased, the resistance value of the negative temperature coefficient thermistor is reduced, and the voltage value of the first voltage signal is reduced. As the voltage value of the first voltage signal increases and decreases, the voltage difference between the voltage value of the first voltage signal and the voltage value of the second voltage signal changes.

In the above embodiment, the temperature measuring circuit 10 can not only detect the actual temperature of the heat source, provide the first voltage signal corresponding to the actual temperature of the heat source and the second voltage signal corresponding to the target temperature, but also set the target temperature. Specifically, when the target temperature is set, the resistance value corresponding to the thermistor Rt when the heat source is at the preset target temperature is acquired, and the resistance value of the third resistor R3 is set to the resistance value corresponding to the thermistor Rt at that time. For better effect, the corresponding resistance value of the thermistor Rt can be acquired when the heat source is at different target temperatures, so that the resistance value of the third resistor R3 can be changed when the target temperature is set, and the purpose of adjusting the target temperature is achieved.

In this embodiment, as shown in fig. 3, the temperature measuring circuit 10 may further include a first filter capacitor C11, and the first filter capacitor C11 is connected in parallel with the thermistor Rt.

Specifically, the first filter capacitor C11 is connected across the port 23 of the first voltage signal output end of the temperature measuring circuit 10 and the ground, so as to filter the high-frequency interference.

In some embodiments, as shown in fig. 2, the PID controller 20 may include a chopping operational amplifier circuit A1, a compensation circuit B1, an integrating operational amplifier circuit A2, a comparison operational amplifier circuit A3, and a PWM (Pulse width modulation) control circuit A6; the middle point of the first bridge arm and the middle point of the second bridge arm are respectively and correspondingly connected with a positive phase end and a reverse end of a chopping operational amplifier circuit A1, the output end of the chopping operational amplifier circuit A1 is connected with a first end of a compensating circuit B1, a second end of the compensating circuit B1 is connected with a reverse end of an integral operational amplifier circuit A2, the output end of the integral operational amplifier circuit A2 is connected with a third end of the compensating circuit B1, the positive end of the integral operational amplifier circuit A2 is grounded, a first input end of a comparison operational amplifier circuit A3 is connected with the output end of the integral operational amplifier circuit A2, and a second input end of the comparison operational amplifier circuit A3 is connected with a preset power supply Vcc; the comparison operational amplifier circuit A3 is used for outputting a control signal for controlling the temperature adjusting mechanism 30 to heat through the PWM control circuit A6 when the voltage Uout output by the integration operational amplifier circuit A2 is greater than the reference voltage U1, and outputting a control signal for controlling the temperature adjusting mechanism 30 to cool through the PWM control circuit A6 when the voltage Uout output by the integration operational amplifier circuit A2 is less than the reference voltage U1.

Specifically, a second voltage signal output by the midpoint of the first arm of the temperature measuring circuit 10 is input to the positive phase end of the chopping operational amplifier circuit A1, a first voltage signal output by the midpoint of the second arm of the temperature measuring circuit 10 is input to the reverse end of the chopping operational amplifier circuit A1, and the chopping operational amplifier circuit A1 amplifies a voltage difference between a voltage value of the first voltage signal input by the reverse end and a voltage value of the second voltage signal input by the positive end. The output end of the chopping operational amplifier A1 outputs the amplified voltage difference and outputs the amplified voltage difference to the first end port 31 of the compensating circuit B1, the series network of the compensating circuit B1 processes the amplified voltage difference and outputs the amplified voltage difference to the inverting end of the integral operational amplifier circuit A2 through the second end port 32 of the compensating circuit B1, the integral operational amplifier circuit A2 performs integral processing on the processed voltage difference and then inputs the processed voltage difference to the third end port 33 of the compensating circuit B1, and the voltage difference is fed back to the inverting end of the integral operational amplifier circuit A2 after being processed by the negative feedback network of the compensating circuit B1. The compensation circuit B1 enables the integral operational amplifier circuit A2 to form a proportional-integral-derivative PID control circuit.

More specifically, after the voltage difference between the first voltage signal and the second voltage signal is amplified by the chopper operational amplifier circuit A1, the voltage difference is regulated by the compensation circuit B1 and the integral operational amplifier circuit A2 through PID, and the output end of the integral operational amplifier circuit A2 outputs a voltage Uout after PID regulation. The integral operational amplifier circuit A2 outputs the voltage Uout after PID adjustment to a first input end of a comparison operational amplifier circuit A3, a second input end of the comparison operational amplifier circuit A3 receives a reference voltage U1, the comparison operational amplifier circuit A3 compares the input voltage Uout with the reference voltage U1, when the voltage Uout is greater than the reference voltage U1, a comparison value of the comparison value outputs a control signal for controlling the temperature adjusting mechanism 30 to heat through a PWM control circuit A6, when the voltage Uout is less than the reference voltage U1, the comparison value of the comparison value outputs a control signal for controlling the temperature adjusting mechanism 30 to refrigerate through the PWM control circuit A6, when the voltage Uout is equal to the reference voltage U1, the comparison value of the comparison value outputs a control signal for controlling the temperature adjusting mechanism 30 not to work through the PWM control circuit A6.

In some embodiments, as shown in fig. 4, the compensation circuit B1 includes a fourth resistor R4, a first capacitor C1, a second capacitor C2, a fifth resistor R5, a third capacitor C3, and a sixth resistor R6, one end of the fifth resistor R5 and one end of the sixth resistor R6 are both connected to the first end of the compensation circuit B1, the other end of the fifth resistor R5 is connected to one end of the third capacitor C3, the other end of the sixth resistor R6, one end of the first capacitor C1, and one end of the second capacitor C2 are both connected to the second end of the compensation circuit B1, the other end of the first capacitor C1 is connected to one end of the fourth resistor R4, and the other end of the fourth resistor R4 and the other end of the second capacitor C2 are both connected to the third end of the compensation circuit B1.

Specifically, the sixth resistor R6, the fifth resistor R5 and the third capacitor C3 connected across the first port 31 and the second port 32 of the compensation circuit B1 form a series network. The first capacitor C1, the fourth resistor R4 and the second capacitor C2 connected in bridge between the second port 32 and the third port 33 of the compensation circuit B1 form a negative feedback network of the integrating operational amplifier A2. The compensation circuit B1 not only enables the integral operational amplifier circuit A2 to form a proportional-integral-derivative (PID) control circuit, but also provides a double pole zero point for a control loop, so that system oscillation can be avoided, and the response speed of the system is accelerated.

In some embodiments, the temperature regulating mechanism 30 may include a semiconductor Cooler (TEC).

The semiconductor cooling sheet has a cold side and a hot side. The direction of the cold surface and the direction of the hot surface can be changed by changing the direction of the current passing through the semiconductor refrigerating sheet. Therefore, when the semiconductor refrigerating sheet is used for heating or radiating heat of the heat source, the orientation of the hot surface and the orientation of the cold surface of the semiconductor refrigerating sheet can be changed by changing the direction of current flowing through the semiconductor refrigerating sheet. And the refrigerating and heating degrees of the hot surface and the cold surface of the semiconductor refrigerating sheet can be changed by changing the current flowing through the semiconductor refrigerating sheet.

In this embodiment, the control signal may be a PWM signal, and the heating or cooling degree of the temperature adjustment mechanism 30 are adjusted by changing the duty ratio and the direction of the PWM signal, so as to change the current magnitude and the current direction of the current signal, so that the heat source is rapidly and stably maintained at the target temperature. When the voltage Uout is larger, the current is larger, the heating or cooling degree of the semiconductor cooling plate is larger, and when the voltage Uout is smaller, the current is smaller, and the heating or cooling degree of the semiconductor cooling plate is smaller.

In some embodiments, the PID controller 20 further includes a driving circuit B2, the driving circuit B2 includes a first inductor L1, a first energy storage capacitor C21, a seventh resistor R7, a second filter capacitor C12, a second energy storage capacitor C22, a second inductor L2, a first PMOS transistor PMOS1, a first NMOS transistor NMOS1, a second PMOS transistor PMOS2, and a second NMOS transistor NMOS2, the semiconductor cooling chip TEC is connected between the seventh resistor R7 and the second energy storage capacitor C22, one end of the first inductor L1 is connected to the drains of the first PMOS transistor PMOS1 and the first NMOS transistor NMOS1, the other end of the first inductor L1 is connected to one end of the first energy storage capacitor C21 and one end of the seventh resistor R7 far away from the semiconductor cooling chip, the other end of the first energy storage capacitor C21 and one end of the second energy storage capacitor C22 far away from the semiconductor cooling chip are both grounded, one end of the second inductor L2 is connected to the drains of the second PMOS transistor PMOS2 and the second NMOS transistor NMOS2, and the other end of the second inductor L2 is connected to the second cooling chip of the semiconductor cooling chip C22; when the PWM control circuit A6 outputs a control signal for controlling the temperature adjustment mechanism 30 to refrigerate, the first PMOS transistor PMOS1 and the second NMOS transistor NMOS2 are turned on, and a current flows to the ground through the first PMOS transistor PMOS1, the first inductor L1, the seventh resistor R7, the semiconductor chilling plate, the second inductor L2, and the second NMOS transistor NMOS2, and forms a BUCK circuit with the first energy storage capacitor C21 and the second energy storage capacitor C22; when the PWM control circuit A6 outputs a control signal for controlling the heating of the temperature adjustment mechanism 30, the second PMOS transistor PMOS2 and the first NMOS transistor NMOS1 are turned on, and the current flows to the ground through the second PMOS transistor PMOS2, the second inductor L2, the semiconductor refrigeration chip, the seventh resistor R7, the first inductor L1, and the first NMOS transistor NMOS1, and forms a BUCK circuit with the first energy storage capacitor C21 and the second energy storage capacitor C22. The grid electrode of the first PMOS tube PMOS1 and the grid electrode of the first NMOS tube NMOS1 are both connected with the PWM control circuit A6, the source electrode of the first PMOS tube PMOS1 is connected with a system power supply, and the source electrode of the first NMOS tube NMOS1 is grounded. The grid electrode of the second PMOS tube PMOS2 and the grid electrode of the second NMOS tube NMOS2 are both connected with the PWM control circuit A6, the source electrode of the second PMOS tube PMOS2 is connected with a system power supply, and the source electrode of the second NMOS tube NMOS2 is grounded.

When the PWM control circuit A6 controls the semiconductor refrigeration piece to refrigerate or heat, the current flowing direction of the semiconductor refrigeration piece is controlled by controlling the first PMOS tube PMOS1 and the second NMOS tube NMOS2 to be conducted simultaneously or controlling the second PMOS tube PMOS2 and the first NMOS tube NMOS1 to be conducted simultaneously, so that the heating surface and the cooling surface of the semiconductor refrigeration piece are changed. The comparison value output by the comparison operational amplifier circuit A3 is input into a PWM control circuit A6 to control the time sequence of the simultaneous conduction of the PMOS tube PMOS1 and the NMOS tube NMOS2 or the simultaneous conduction of the PMOS tube PMOS2 and the NMOS tube NMOS1, the voltage of the BUCK circuit is changed by changing the duty ratio of the PWM control circuit, and the voltage changes the further current along with the change, thereby controlling the refrigerating or heating degree of the temperature adjusting mechanism 30.

Specifically, the first port 41 and the second port 45 of the driving circuit B2 are both bidirectional ports, and can be used as output ends or input ends. Further specifically, when the temperature adjustment mechanism 30 is controlled to refrigerate, the PWM control circuit A6 controls the conduction of the first PMOS tube PMOS1 and the second NMOS tube NMOS2, the first end port 41 of the driving circuit B2 is an input end, the second end port 45 of the driving circuit B2 is an output end, the current passes through the first PMOS tube PMOS1, the first inductor L1, the seventh resistor R7, the semiconductor refrigeration sheet, the second inductor L2, the second NMOS tube NMOS2 to the ground end, and forms a BUCK circuit with the first energy storage capacitor C21 and the second energy storage capacitor C22, and the semiconductor refrigeration sheet heats the heat source on the side facing the heat source. When the temperature adjusting mechanism 30 is controlled to heat, the PWM control circuit A6 controls the conduction of the second PMOS transistor PMOS2 and the first NMOS transistor NMOS1, the second port 45 of the driving circuit B2 is an input end, the driving circuit B2 is an output end of the first port 41, the current flows to the ground end through the second PMOS transistor PMOS2, the second inductor L2, the semiconductor chilling plate, the seventh resistor R7, the first inductor L1 and the first NMOS transistor NMOS1, and forms a BUCK circuit with the first energy storage capacitor C21 and the second energy storage capacitor C22, and the semiconductor chilling plate refrigerates the side facing the heat source to dissipate the heat source.

In the driving circuit B2, the first storage capacitor C21 and the second storage capacitor C22 function as storage and filtering. The second filter capacitor C12 functions as a filter. The first inductor L1, the first energy storage capacitor C21, the seventh resistor R7, the second filter capacitor C12, the second energy storage capacitor C22, the second inductor L2, the first PMOS tube PMOS1, the first NMOS tube NMOS1, the second PMOS tube PMOS2 and the second NMOS tube NMOS2 are connected to form a bidirectional BUCK circuit, the direction of current can be changed, and therefore the semiconductor refrigeration piece can heat or refrigerate a heat source.

In some embodiments, as shown in fig. 5, the PID controller 20 further includes a current sampling operational amplifier circuit A4 and a voltage sampling operational amplifier circuit A5, a positive phase end of the current sampling operational amplifier circuit A4 is connected to one end of the seventh resistor R7, which is connected to the semiconductor chilling plate TEC, a negative phase end of the current sampling operational amplifier circuit A4 is connected to one end of the seventh resistor R7, which is connected to the first inductor L1, a positive phase end of the voltage sampling operational amplifier circuit A5 is connected to one end of the semiconductor chilling plate TEC, which is connected to the second inductor L2, and a negative phase end of the voltage sampling operational amplifier circuit A5 is connected to one end of the seventh resistor R7, which is connected to the semiconductor chilling plate TEC.

The current sampling operational amplifier circuit A4 is used for monitoring the working current of the semiconductor refrigeration chip TEC, specifically, a first output port 42 of the driving circuit B2 is connected with a negative phase end of the current sampling operational amplifier circuit A4, a second output port 43 of the driving circuit B2 is connected with a positive phase end of the current sampling operational amplifier circuit A4, a seventh resistor R7 is bridged between the first output port 42 and the second output port 43, the current sampling operational amplifier circuit A4 detects the current magnitude of the semiconductor refrigeration chip TEC, and feeds the current magnitude of the semiconductor refrigeration chip back to the PWM control circuit, so that the semiconductor refrigeration chip is prevented from being burnt down due to overlarge current.

The voltage acquisition operational amplifier circuit A5 is used for monitoring the working voltage of the semiconductor refrigerating chip TEC. Specifically, the second output port 43 of the driving circuit B2 and the negative phase end of the voltage sampling operational amplifier circuit A5, the third output port 44 of the driving circuit B2 and the positive phase end of the voltage sampling operational amplifier circuit A5, and the semiconductor refrigerating chip TEC is bridged between the second output port 43 and the third output port 44, and the voltage sampling operational amplifier circuit A5 detects the current voltage of the semiconductor refrigerating chip TEC and feeds the current voltage back to the PWM control circuit, thereby preventing the voltage from exceeding the withstand voltage of the semiconductor refrigerating chip and causing damage.

In some embodiments, the thermostatic device 100 further includes a heat sink disposed corresponding to the semiconductor chilling plate for dissipating heat from the semiconductor chilling plate.

Specifically, the plane of the radiating fin is attached to the default hot surface of the semiconductor refrigerating sheet, so that when the semiconductor refrigerating sheet is in a heating working state, the heat of the hot surface of the semiconductor refrigerating sheet can be rapidly led out, and the semiconductor refrigerating sheet is prevented from being burnt. Wherein, the radiating fin can be a groove-shaped metal radiating fin.

For better effect, heat conduction materials, such as heat conduction silicone grease or heat conduction silica gel, are filled between the semiconductor refrigeration piece and the heat radiating fin and between the semiconductor refrigeration piece and the heat source, so that the heat source, the semiconductor refrigeration piece and the heat radiating fin are heated uniformly, friction among the heat source, the semiconductor refrigeration piece and the heat radiating fin is buffered, and the semiconductor refrigeration piece is prevented from being damaged.

In some embodiments, the thermostatic device 100 further includes a heat dissipation fan disposed corresponding to the semiconductor cooling plate for dissipating heat from the semiconductor cooling plate.

Specifically, the cooling fan blows air to the cooling fins to assist the semiconductor refrigeration fins in cooling. The heat dissipation fan may selectively dissipate heat roughly from a heat sink and a heat source when the thermostat device 100 is in operation.

In the thermostat device in the embodiment, the thermistor Rt detects the actual temperature of the heat source, and changes the resistance value thereof according to the actual temperature of the heat source, the temperature measuring circuit 10 provides a first voltage signal corresponding to the actual temperature and a second voltage signal corresponding to the target temperature, the PID controller 20 performs PID adjustment according to the voltage difference between the first voltage signal corresponding to the actual temperature and the second voltage signal corresponding to the target temperature to output an accurate control signal, and controls the temperature adjusting mechanism 30 to refrigerate and dissipate heat of the heat source when the actual temperature of the heat source is higher than the target temperature; when the actual temperature of the heat source is lower than the target temperature, the temperature adjusting mechanism 30 is controlled to heat the heat source, and when the actual temperature of the heat source is equal to the target temperature, the temperature adjusting mechanism 30 is controlled not to work. The temperature of the heat source is accurately controlled, so that the heat source is stabilized at the target temperature, and the overheating or overcooling of the heat source is effectively prevented. And the temperature can be accurate to 0.001 deg.c.

Based on foretell constant temperature equipment, the utility model also provides an on-vehicle new line display.

Fig. 6 is a schematic structural diagram of an on-vehicle head-up display according to an embodiment of the present invention. As shown in fig. 6, the vehicle-mounted head-up display 1000 includes a display screen 300, a backlight module 200 and the thermostat 100 as described above, wherein the backlight module 200 is used as a heat source for providing backlight for imaging of the display screen 300.

Referring to fig. 6, the in-vehicle head-up display 1000 includes a display screen 300, a backlight module 31, and a thermostat 100. The backlight module 200 provides stable and reliable backlight for LCD and DLP imaging, so that the display screen 300 can be imaged, and thus, the backlight module 200 can generate a large amount of heat. The thermostat 100 heats or dissipates the heat of the backlight module 200 according to the actual temperature of the backlight module 200, so that the actual temperature of the backlight module 200 is stabilized at the target temperature to prevent the backlight module 200 from being burnt out due to over-high temperature and heat dissipation, and to prevent the backlight module 200 from being failed at low temperature and partial components of the backlight module 200 from being burnt out.

In this embodiment, the temperature measuring circuit 10 of the thermostat 100 may be a flexible circuit board, and the thermistor Rt is a negative feedback coefficient thermistor. Specifically, the degeneration coefficient thermistor is welded on a flexible circuit board, which is fixed on the backlight module 200, so as to detect the actual temperature of the backlight module 200.

In this embodiment, the heat conductive material 40 may be a heat conductive silicone grease or a heat conductive silicone, and the heat sink may be a groove-shaped metal heat sink 50. The heat conduction materials are filled between the semiconductor refrigeration piece and the groove-shaped metal radiating fin and between the semiconductor refrigeration piece and the backlight module 200, so that the backlight module 200, the conductor refrigeration piece and the groove-shaped metal radiating fin are heated uniformly, friction among the backlight module 200, the conductor refrigeration piece and the groove-shaped metal radiating fin can be buffered, and the semiconductor refrigeration piece is prevented from being damaged.

Under the effect of the thermostat device 100, the vehicle-mounted head-up display 1000 in this embodiment can achieve an automatic constant temperature effect even in environments with large brightness change, cold and hot, so that the vehicle-mounted head-up display 1000 works more stably, user experience is improved, and the problems that the backlight module 300 of the existing vehicle-mounted head-up display 1000 dissipates heat roughly and cannot work normally in a low-temperature environment are solved.

Based on foretell constant temperature equipment, the utility model also provides a vehicle.

Fig. 7 is a schematic structural diagram of a vehicle according to an embodiment of the present invention. As shown in fig. 7, the vehicle 2000 includes the on-board heads-up display 1000 as described above.

Specifically, by installing the vehicle-mounted head-up display 1000 in the vehicle 2000, the vehicle-mounted head-up display 1000 can achieve an automatic constant temperature effect in environments with large brightness change, cold and hot, and can prevent the vehicle-mounted head-up display 1000 from being out of work in a low-temperature environment, so that user experience is improved.

It should be noted that the logic and/or steps represented in the flowcharts or otherwise described herein, such as an ordered listing of executable instructions that can be considered to implement logical functions, can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic device) having one or more wires, a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.

It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or combination of the following technologies, which are well known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship indicated based on the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless explicitly defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

While embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations of the above embodiments may be made by those of ordinary skill in the art without departing from the scope of the present invention.

Claims

1. A thermostatic device, characterized in that it comprises:

the temperature adjusting mechanism is used for adjusting the temperature of the heat source;

the temperature measuring circuit is used for detecting the actual temperature of the heat source;

and the PID controller is respectively connected with the temperature measuring circuit and the temperature regulating mechanism and is used for carrying out PID regulation according to the actual temperature and the target temperature to obtain a control signal and controlling the temperature regulating mechanism to heat or refrigerate according to the control signal so as to stabilize the temperature of the heat source at the target temperature.

2. The thermostat device according to claim 1, wherein the temperature measuring circuit comprises a first resistor, a second resistor, a third resistor and a thermistor, the first resistor, the second resistor, the thermistor and the third resistor are connected end to form a Wheatstone bridge, the first resistor and the second resistor form a first bridge arm of the Wheatstone bridge, the third resistor and the thermistor form a second bridge arm of the Wheatstone bridge, one end of the first bridge arm connected with the first resistor is connected with a preset power supply, and one end of the first bridge arm connected with the second resistor is grounded;

the preset power supply is used for providing reference voltage, the resistance value of the third resistor is equal to the resistance value of the thermistor corresponding to the target temperature, the thermistor is arranged corresponding to the heat source, and the midpoint of the first bridge arm and the midpoint of the second bridge arm are both connected with the PID controller and used for providing a first voltage signal corresponding to the actual temperature and a second voltage signal corresponding to the target temperature for the PID controller.

3. The thermostat device of claim 2, wherein the thermometry circuit further comprises:

the first filter capacitor is connected with the thermistor in parallel.

4. The thermostat device according to claim 2 or 3, wherein the PID controller comprises a chopping operational amplifier circuit, a compensation circuit, an integral operational amplifier circuit, a comparison operational amplifier circuit and a PWM control circuit;

the middle point of the first bridge arm and the middle point of the second bridge arm are respectively and correspondingly connected with the positive phase end and the reverse end of the chopping operational amplifier circuit, the output end of the chopping operational amplifier circuit is connected with the first end of the compensation circuit, the second end of the compensation circuit is connected with the reverse end of the integral operational amplifier circuit, the output end of the integral operational amplifier circuit is connected with the third end of the compensation circuit, the positive end of the integral operational amplifier circuit is grounded, the first input end of the comparison operational amplifier circuit is connected with the output end of the integral operational amplifier circuit, and the second input end of the comparison operational amplifier circuit is connected with the preset power supply;

the comparison operational amplifier circuit is used for outputting a control signal for controlling the temperature adjusting mechanism to heat through the PWM control circuit when the voltage output by the integral operational amplifier circuit is greater than the reference voltage, and outputting a control signal for controlling the temperature adjusting mechanism to refrigerate through the PWM control circuit when the voltage output by the integral operational amplifier circuit is less than the reference voltage.

5. The thermostat device according to claim 4, wherein the compensation circuit comprises a fourth resistor, a first capacitor, a second capacitor, a fifth resistor, a third capacitor and a sixth resistor, one end of the fifth resistor and one end of the sixth resistor are connected to the first end of the compensation circuit, the other end of the fifth resistor is connected with one end of the third capacitor, the other end of the sixth resistor, one end of the first capacitor and one end of the second capacitor are connected to the second end of the compensation circuit, the other end of the first capacitor is connected with one end of the fourth resistor, and the other end of the fourth resistor and the other end of the second capacitor are connected to the third end of the compensation circuit.

6. The thermostat device according to claim 4, wherein the temperature adjusting mechanism comprises a semiconductor chilling plate, the PID controller further comprises a driving circuit, the driving circuit comprises a first inductor, a first energy storage capacitor, a seventh resistor, a second filter capacitor, a second energy storage capacitor, a second inductor, a first PMOS tube, a first NMOS tube, a second PMOS tube and a second NMOS tube,

the semiconductor refrigeration piece is connected between the seventh resistor and the second energy storage capacitor, one end of the first inductor is connected with the drain electrodes of the first PMOS tube and the first NMOS tube respectively, the other end of the first inductor is connected with one end of the first energy storage capacitor and one end of the seventh resistor, which is far away from the semiconductor refrigeration piece, respectively, the other end of the first energy storage capacitor and one end of the second energy storage capacitor, which is far away from the semiconductor refrigeration piece, are both grounded, one end of the second inductor is connected with the drain electrodes of the second PMOS tube and the second NMOS tube respectively, and the other end of the second inductor is connected with one end of the semiconductor refrigeration piece, which is connected with the second energy storage capacitor;

when the PWM control circuit outputs a control signal for controlling the temperature adjusting mechanism to refrigerate, the first PMOS tube and the second NMOS tube are conducted, and current flows to the ground end through the first PMOS tube, the first inductor, the seventh resistor, the semiconductor refrigerating sheet, the second inductor and the second NMOS tube and forms a BUCK circuit together with the first energy storage capacitor and the second energy storage capacitor;

when the PWM control circuit outputs a control signal for controlling the temperature adjusting mechanism to heat, the second PMOS tube and the first NMOS tube are conducted, and current flows to the ground end through the second PMOS tube, the second inductor, the semiconductor refrigerating sheet, the seventh resistor, the first inductor and the first NMOS tube and forms a BUCK circuit with the first energy storage capacitor and the second energy storage capacitor.

7. The constant temperature device according to claim 6, wherein the PID controller further comprises a current sampling operational amplifier circuit and a voltage sampling operational amplifier circuit, a positive phase end of the current sampling operational amplifier circuit is connected with one end of the seventh resistor connected with the semiconductor refrigeration piece, a negative phase end of the current sampling operational amplifier circuit is connected with one end of the seventh resistor connected with the first inductor, a positive phase end of the voltage sampling operational amplifier circuit is connected with one end of the semiconductor refrigeration piece connected with the second inductor, a negative phase end of the voltage sampling operational amplifier circuit is connected with one end of the semiconductor refrigeration piece connected with the seventh resistor, and output ends of the current sampling operational amplifier circuit and the voltage sampling operational amplifier circuit are connected with the PWM control circuit.

8. The thermostat device as claimed in claim 6, further comprising a heat sink disposed in correspondence with the semiconductor chilling plate for dissipating heat from the semiconductor chilling plate.

9. The thermostatic device according to claim 6, further comprising a heat dissipation fan disposed corresponding to the semiconductor chilling plate for dissipating heat from the semiconductor chilling plate.

10. The thermostat device of claim 2, wherein the thermistor is soldered to a flexible circuit board that is fixed at the heat source.

11. A vehicle-mounted head-up display, comprising a display screen, a backlight module and the thermostat device as claimed in claims 1-10, wherein the backlight module is used as the heat source for providing backlight for the display screen.

12. A vehicle comprising the on-board heads-up display of claim 11.