Intelligent control microwave heater
Technical Field
The invention relates to an electric heater, in particular to an intelligent control microwave heater.
Background
Energy shortage becomes an important problem restricting economic development of China. In the current composition of primary energy consumption in China, coal accounts for 66%. At present, the heating mode which is the dominating place in China still is centralized heating mainly by using coal as fuel, the coal consumption of heating accounts for nearly half of the annual coal consumption, and the defects of the heating mode are increasingly shown: firstly wasting energy and resources, such as coal resources, water resources and heat energy lost during the transmission process, and secondly polluting the environment. Therefore, the novel heating mode is created, and the novel heat source is adopted, so that the novel heating system has great significance for reducing energy consumption, protecting the environment and building a conservation-oriented society.
An electric heater is a high-quality and long-life electric heating device which is popular internationally and is a process for converting electric energy into heat energy. Since the discovery that the thermal effects of power sources can occur through the wires, many inventors have engaged in the research and manufacture of various electric heating appliances in the world. The electric heater is mainly used for heating, preserving heat and heating flowing liquid and gaseous media, and when the heating medium passes through the heating cavity of the electric heater under the action of pressure, huge heat generated in the working process of the electric heating element is uniformly taken away by adopting the fluid thermodynamic principle, so that the temperature of the heated medium meets the process requirements of users. The current common heating mode of the electric heater is resistance heating, and the joule effect of the current is utilized to convert the electric energy into heat energy to heat the object, which is generally divided into direct resistance heating and indirect resistance heating. Common resistance wire heating, ceramic heaters, resistance coil heating and quartz tube heating belong to resistance heating in principle.
However, resistive heaters are the most primitive in heating and therefore have the worst thermal efficiency, typically only about seventy percent, with a large amount of heat being dissipated into the air. Meanwhile, the existing electric heater can automatically cut off the circuit to stop heating when the temperature reaches a certain temperature, and can restart heating when the temperature is lower than the certain temperature, but because the electric heater is too long in heating time, people often forget the electric heater which is heating, so that the temperature of the electric heater is reduced within a period of time after the electric heater finishes heating, the electric heater can be reheated, the service life of the electric heater can be shortened while electric energy is consumed, and potential safety hazards such as fire hazard occur.
Disclosure of Invention
In order to solve the technical problems, the invention provides an intelligent control microwave heater, which comprises an intelligent control device and a heater, wherein the heater comprises a microwave generator, a microwave heating cavity and a heat-conducting medium, and the intelligent control device comprises a control circuit, an electronic switch, a power supply, an external power supply and a negative temperature coefficient thermistor; one end of the microwave generator is connected with the electronic switch, the other end of the microwave generator is connected with the microwave heating cavity, the heat-conducting medium is arranged in the microwave heating cavity, the microwave generator generates microwaves after being electrified, and the heat-conducting medium is heated through the microwave heating cavity; one end of the electronic switch is connected with an external power supply, and the other end of the electronic switch is connected with the heater; the power supply is connected with the negative temperature coefficient thermistor and the control circuit and is connected in series to form a closed loop;
the control circuit comprises a current measuring module, a counting module and a control module, wherein the current measuring module is used for measuring the current of the closed loop, the counting module is used for counting the times that the current measured by the current measuring module reaches a preset threshold value, and the control module is used for controlling the electronic switch to be connected or disconnected when the current measured by the current measuring module reaches a preset value and controlling the electronic switch to be kept disconnected when the count of the counting module reaches the preset threshold value.
Specifically, the controller is a programmable logic controller.
Optionally, the power supply is a dc power supply, and the external power supply is an ac power supply.
Preferably, the microwave generator comprises a rectifying device and a microwave tube, wherein the rectifying device is used for converting alternating current of the external power supply into direct current, and the microwave tube is used for converting electric energy into microwave energy.
Further, the rectifying device is an electron tube.
Preferably, the rectifying device is a crystal diode.
Optionally, the intelligent control microwave heater further comprises an alarm module, wherein the alarm module is respectively connected with the power supply and the control circuit and is used for sending an alarm signal when the current measured by the current measuring module reaches a preset threshold value.
Preferably, the alarm module is used for generating an alarm signal when the counting module reaches a preset number.
Specifically, the data stored in the counting module is automatically cleared after power failure.
Optionally, the control module is a logic circuit.
The application of the invention has the following beneficial effects:
according to the invention, the intelligent control device is arranged, the number of times of circulating heating is judged through the counting module, and the heating power supply is cut off by controlling the electronic switch to be switched off when the number of times of heating reaches a certain amount, so that the problem of circulating heating of the electric heater caused by forgetting or unattended operation is effectively solved, the loss of the electric heater caused by circulating heating is avoided, the electric energy can be saved, and the electric heating device is energy-saving and environment-friendly.
The heater is a microwave heater, the microwave tube of the microwave generator is operated by an external power supply to convert electric energy into microwave energy, the microwave passes through the microwave heating cavity to heat the heat-conducting medium in the microwave heating cavity, and the heating mode is higher in heat efficiency than resistance heating and is safer and more reliable.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions and advantages of the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a block diagram of an intelligent control microwave heater according to a first embodiment and a second embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
The first embodiment is as follows:
referring to fig. 1, an embodiment of the present invention provides an intelligent control microwave heater, including an intelligent control device and a heater, where the heater includes a microwave generator, a microwave heating cavity, and a heat-conducting medium, and the intelligent control device includes a control circuit, an electronic switch, a power supply, an external power supply, and a negative temperature coefficient thermistor; one end of the microwave generator is connected with the electronic switch, the other end of the microwave generator is connected with the microwave heating cavity, the heat-conducting medium is arranged in the microwave heating cavity, the microwave generator generates microwaves after being electrified, and the heat-conducting medium is heated through the microwave heating cavity; one end of the electronic switch is connected with an external power supply, and the other end of the electronic switch is connected with the heater; the power supply is connected with the negative temperature coefficient thermistor and the control circuit and is connected in series to form a closed loop;
the control circuit comprises a current measuring module, a counting module and a control module, wherein the current measuring module is used for measuring the current of the closed loop, the counting module is used for counting the times that the current measured by the current measuring module reaches a preset threshold value, and the control module is used for controlling the electronic switch to be connected or disconnected when the current measured by the current measuring module reaches a preset value and controlling the electronic switch to be kept disconnected when the count of the counting module reaches the preset threshold value.
The negative temperature coefficient thermistor is manufactured by adopting a ceramic process and taking metal oxides of manganese, cobalt, nickel, copper and the like as main materials, and the metal oxide materials all have semiconductor properties because the metal oxide materials are completely similar to semiconductor materials of germanium, silicon and the like in a conduction mode. At low temperatures, these oxide materials have a low number of carriers (electrons and holes) and therefore have a high resistance; as the temperature increases, the number of carriers increases, so the resistance value decreases.
When the circuit works normally, the temperature of the negative temperature coefficient thermistor is close to the room temperature, the resistance is high, and the negative temperature coefficient thermistor is connected in series in the circuit to cause that the passing current is small; when the temperature is higher and exceeds the switch temperature, the resistance is instantly reduced, the current in the loop is rapidly increased, and the current in the circuit is greatly improved after the thermistor acts. The negative temperature coefficient thermistor can convert the temperature signal into an electric signal, so that the control of the control circuit based on the temperature is realized.
The temperature of the electric heater is divided into a low-temperature opening temperature and a high-temperature cut-off temperature, the high-temperature cut-off temperature refers to the temperature for stopping heating when the temperature is higher than a preset temperature, such as 60 ℃, when the high-temperature cut-off temperature is reached, correspondingly, the resistance value of the negative temperature coefficient thermistor is reduced to a certain value, the current in the closed loop is also increased to a certain value, a control module in the control circuit controls the electronic switch to open the circuit, and the electric heater stops heating; the low temperature turn-on temperature refers to a temperature at which the electric heater starts to heat below a predetermined temperature, for example, 20 ℃. When the low-temperature opening temperature is reached, correspondingly, the resistance value of the thermistor with the negative temperature coefficient is increased to a certain value, the current of the closed circuit is also reduced to a certain value, the control module in the control circuit controls the electronic switch to be connected with the circuit, and the electric heater starts to heat. When the current measuring module measures that the current reaches a preset temperature, such as a high-temperature cut-off temperature, the counting value of the counting module is increased by one, and when the counting value of the counting module reaches a preset value, such as three, the control module in the control circuit controls the electronic switch to be kept disconnected, and the electric heater does not heat any more.
Specifically, the controller is a programmable logic controller.
Optionally, the power supply is a dc power supply, and the external power supply is an ac power supply.
Preferably, the microwave generator comprises a rectifying device and a microwave tube, wherein the rectifying device is used for converting alternating current of the external power supply into direct current, and the microwave tube is used for converting electric energy into microwave energy.
Further, the rectifying device is an electron tube.
Optionally, the intelligent control microwave heater further comprises an alarm module, wherein the alarm module is respectively connected with the power supply and the control circuit and is used for sending an alarm signal when the current measured by the current measuring module reaches a preset threshold value.
Preferably, the alarm module is used for generating an alarm signal when the counting module reaches a preset number.
Specifically, the data stored in the counting module is automatically cleared after power failure.
Optionally, the control module is a logic circuit.
The application of the invention has the following beneficial effects: the invention adopts a microwave heating mode, has higher thermal efficiency than the traditional resistance heating mode, judges the number of times of circulating heating through the counting module by arranging the intelligent control device, and cuts off the heating power supply by controlling the disconnection of the electronic switch when the number of times of heating reaches a certain amount, thereby effectively solving the problem of circulating heating of the electric heater caused by forgetting or unattended operation, avoiding the loss of the electric heater caused by the circulating heating, saving electric energy, saving energy and protecting environment.
Example two:
referring to fig. 1, an embodiment of the present invention provides an intelligent control microwave heater, including an intelligent control device and a heater, where the heater includes a microwave generator, a microwave heating cavity, and a heat-conducting medium, and the intelligent control device includes a control circuit, an electronic switch, a power supply, an external power supply, and a negative temperature coefficient thermistor; one end of the microwave generator is connected with the electronic switch, the other end of the microwave generator is connected with the microwave heating cavity, the heat-conducting medium is arranged in the microwave heating cavity, the microwave generator generates microwaves after being electrified, and the heat-conducting medium is heated through the microwave heating cavity; one end of the electronic switch is connected with an external power supply, and the other end of the electronic switch is connected with the heater; the power supply is connected with the negative temperature coefficient thermistor and the control circuit and is connected in series to form a closed loop;
the control circuit comprises a current measuring module, a counting module and a control module, wherein the current measuring module is used for measuring the current of the closed loop, the counting module is used for counting the times that the current measured by the current measuring module reaches a preset threshold value, and the control module is used for controlling the electronic switch to be connected or disconnected when the current measured by the current measuring module reaches a preset value and controlling the electronic switch to be kept disconnected when the count of the counting module reaches the preset threshold value.
The negative temperature coefficient thermistor is manufactured by adopting a ceramic process and taking metal oxides of manganese, cobalt, nickel, copper and the like as main materials, and the metal oxide materials all have semiconductor properties because the metal oxide materials are completely similar to semiconductor materials of germanium, silicon and the like in a conduction mode. At low temperatures, these oxide materials have a low number of carriers (electrons and holes) and therefore have a high resistance; as the temperature increases, the number of carriers increases, so the resistance value decreases.
When the circuit works normally, the temperature of the negative temperature coefficient thermistor is close to the room temperature, the resistance is high, and the negative temperature coefficient thermistor is connected in series in the circuit to cause that the passing current is small; when the temperature is higher and exceeds the switch temperature, the resistance is instantly reduced, the current in the loop is rapidly increased, and the current in the circuit is greatly improved after the thermistor acts. The negative temperature coefficient thermistor can convert the temperature signal into an electric signal, so that the control of the control circuit based on the temperature is realized.
The temperature of the electric heater is divided into a low-temperature opening temperature and a high-temperature cut-off temperature, the high-temperature cut-off temperature refers to the temperature for stopping heating when the temperature is higher than a preset temperature, such as 60 ℃, when the high-temperature cut-off temperature is reached, correspondingly, the resistance value of the negative temperature coefficient thermistor is reduced to a certain value, the current in the closed loop is also increased to a certain value, a control module in the control circuit controls the electronic switch to open the circuit, and the electric heater stops heating; the low temperature turn-on temperature refers to a temperature at which the electric heater starts to heat below a predetermined temperature, for example, 20 ℃. When the low-temperature opening temperature is reached, correspondingly, the resistance value of the thermistor with the negative temperature coefficient is increased to a certain value, the current of the closed circuit is also reduced to a certain value, the control module in the control circuit controls the electronic switch to be connected with the circuit, and the electric heater starts to heat. When the current measuring module measures that the current reaches a preset temperature, such as a high-temperature cut-off temperature, the counting value of the counting module is increased by one, and when the counting value of the counting module reaches a preset value, such as three, the control module in the control circuit controls the electronic switch to be kept disconnected, and the electric heater does not heat any more.
Specifically, the controller is a programmable logic controller.
Optionally, the power supply is a dc power supply, and the external power supply is an ac power supply.
Preferably, the microwave generator comprises a rectifying device and a microwave tube, wherein the rectifying device is used for converting alternating current of the external power supply into direct current, and the microwave tube is used for converting electric energy into microwave energy.
Further, the rectifying device is a crystal diode.
Optionally, the intelligent control microwave heater further comprises an alarm module, wherein the alarm module is respectively connected with the power supply and the control circuit and is used for sending an alarm signal when the current measured by the current measuring module reaches a preset threshold value.
Preferably, the alarm module is used for generating an alarm signal when the counting module reaches a preset number.
Specifically, the data stored in the counting module is automatically cleared after power failure.
Optionally, the control module is a logic circuit.
The application of the invention has the following beneficial effects: the invention adopts a microwave heating mode, has higher thermal efficiency than the traditional resistance heating mode, judges the number of times of circulating heating through the counting module by arranging the intelligent control device, and cuts off the heating power supply by controlling the disconnection of the electronic switch when the number of times of heating reaches a certain amount, thereby effectively solving the problem of circulating heating of the electric heater caused by forgetting or unattended operation, avoiding the loss of the electric heater caused by the circulating heating, saving electric energy, saving energy and protecting environment.
While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.