CN115015294A - Microwave sensor and icing and frosting detection equipment based on microwave sensor - Google Patents
Microwave sensor and icing and frosting detection equipment based on microwave sensor Download PDFInfo
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- CN115015294A CN115015294A CN202210599527.5A CN202210599527A CN115015294A CN 115015294 A CN115015294 A CN 115015294A CN 202210599527 A CN202210599527 A CN 202210599527A CN 115015294 A CN115015294 A CN 115015294A
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Abstract
The invention discloses a microwave sensor and icing and frosting detection equipment based on the microwave sensor, which comprises a radio frequency microwave signal source, a coupler and a detector, wherein the radio frequency microwave signal source, the coupler and the detector are arranged on a single PCB (printed circuit board); the radio frequency microwave signal source is used for generating a radio frequency microwave signal and sending the radio frequency microwave signal to the coupler; the coupler is set to be exposed in the air so as to detect the icing and frosting phenomena in the environment and transmit the radio frequency microwave signal generated by the radio frequency microwave signal source; the detector is used for receiving the radio frequency microwave signals transmitted by the coupler, converting the energy of the radio frequency microwave signals into direct current signals and outputting the direct current signals to an external upper computer. The invention is built by only a plurality of separating devices which are arranged on the single PCB, so the cost is low; and the sensor has small volume and simple structure, can be tightly attached to the condensing sheet, and can greatly improve the efficiency of deicing and defrosting.
Description
Technical Field
The invention relates to the technical field of deicing and defrosting industries, in particular to a microwave sensor and icing and frosting detection equipment based on the microwave sensor.
Background
With the improvement of living standard and the requirement of living quality, the refrigerator has become a necessity. In the using process of the refrigerator, the freezing refrigerating chamber is often frozen, and the like, so that the use of the refrigerator is seriously influenced.
Aiming at the problem of icing and frosting of a condenser in the using process of a refrigerator, the current detection and defrosting modes are generally two types: one is to periodically defrost; the other is that a defrosting sensor is used for defrosting when frost is detected. For the periodic defrosting mode, in order to ensure the defrosting effect, no matter whether the surface of the condenser is frosted or not, the periodic defrosting is required, and the energy consumption of the refrigerator is greatly increased. In the mode of passing through the defrosting sensor, the defrosting sensor is required to have higher accuracy, otherwise, the defrosting action is easily triggered by mistake.
The existing defrosting sensor mainly has two methods, namely a mechanical method and a capacitance method. The two icing and frosting sensors have the common characteristics of large volume and high price, and are not beneficial to popularization on white household appliances. In order to achieve the purpose of accurate measurement, the capacitance sensor needs to increase the volume of the capacitance sensor to increase the capacitance volume, however, the larger volume will increase the cost of the whole refrigerator product, and the installation is not suitable.
The above background disclosure is only for the purpose of assisting understanding of the inventive concept and technical solutions of the present invention, and does not necessarily belong to the prior art of the present patent application, and should not be used for evaluating the novelty and inventive step of the present application in the case that there is no clear evidence that the above content is disclosed at the filing date of the present patent application.
Disclosure of Invention
The invention aims to provide a microwave sensor and an icing and frosting detection device based on the microwave sensor, so as to solve at least one of the above background technical problems.
In order to achieve the above purpose, the technical solution of the embodiment of the present invention is implemented as follows:
a microwave sensor, comprising: the radio frequency microwave signal source, the coupler and the detector are arranged on the single PCB; the radio frequency microwave signal source is used for generating a radio frequency microwave signal and sending the radio frequency microwave signal to the coupler; the coupler is set to be exposed in the air so as to detect the icing and frosting phenomena in the environment and transmit the radio frequency microwave signal generated by the radio frequency microwave signal source; the detector is used for receiving the radio frequency microwave signal transmitted by the coupler, detecting the radio frequency microwave signal to convert the energy of the radio frequency microwave signal into a direct current signal, and outputting the direct current signal to an external upper computer.
In some embodiments, the microwave signal source comprises a power source, a field effect transistor, a microstrip resonator; wherein, a current limiting resistor and a choke capacitor are also arranged between the power supply and the field effect tube.
In some embodiments, the microwave signal source is built by using a single separation device; the microstrip resonator is a microstrip line formed on a PCB.
In some embodiments, a dc blocking capacitor is further disposed between the microstrip resonator and the coupler.
In some embodiments, the coupler is formed by a plurality of microstrip lines, and the microstrip lines are configured to be exposed to the air of the tested environment.
In some embodiments, the detector comprises a diode that receives the input signal of the coupler.
In some embodiments, the rf microwave signal source, the coupler, and the detector are disposed on the same side of the PCB.
In some embodiments, the rf microwave signal source and the detector are disposed at two ends of the PCB, respectively, and the coupler is disposed in the middle of the PCB.
The other technical scheme of the embodiment of the invention is as follows:
an icing and frosting detection device based on a microwave sensor comprises the microwave sensor, a base, a sealing sheet and a cover plate, wherein the microwave sensor is arranged on the base; the PCB, the sealing sheet and the cover plate correspond to the positioning column, and fixing holes are formed in the positioning column and matched with the fixing holes to fix the PCB, the sealing sheet and the cover plate on the base.
In some embodiments, the sealing sheet and the cover plate are provided with concave openings corresponding to the positions of the couplers of the microwave sensors on the PCB, so that the couplers of the microwave sensors are exposed to the tested environment.
The technical scheme of the invention has the beneficial effects that:
the microwave sensor and the icing and frosting detection equipment based on the microwave sensor are built only by the separating devices, the separating devices are arranged on the single PCB, the sensor is small in size, simple in structure and low in cost, can be tightly attached to the condensing sheet, and can greatly improve the deicing and defrosting efficiency.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a schematic diagram of a microwave sensor according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a microwave sensor on a PCB board according to an embodiment of the invention;
FIG. 3 is a schematic diagram of an equivalent circuit of a microwave sensor according to an embodiment of the present invention;
4A-4C are graphical representations of detection signals of a microwave sensor according to an embodiment of the present invention;
FIG. 5 is a structural illustration of a microwave sensor-based icing frost detection apparatus according to another embodiment of the present invention;
FIG. 6 is an exploded view of a microwave sensor based icing frost detection apparatus according to another embodiment of the present invention.
Detailed Description
In order to make the technical problems, technical solutions and advantages to be solved by the embodiments of the present invention clearer and more obvious, so that those skilled in the art can better understand the solutions of the present invention, 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 some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element. The connection may be for fixation or for circuit connection.
It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for convenience in describing the embodiments of the present invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be in any way limiting of 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 one or more of that feature. In the description of the embodiments of the present invention, unless otherwise explicitly specified or limited, "plurality" means two or more, and the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as meaning 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 may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
The embodiment of the invention provides a microwave sensor and an icing and frosting detection device based on the microwave sensor, which can directly detect the icing and frosting condition of a detected object, have low cost and simple structure and are beneficial to energy conservation and environmental protection.
Fig. 1 is a schematic diagram of a microwave sensor for sensing icing and frosting of a measured object according to an embodiment of the present invention, and the microwave sensor includes a radio frequency microwave signal source 1, a coupler 2, and a detector 3, which are disposed on a single PCB; the radio frequency microwave signal source 1 is used for generating a radio frequency microwave signal and sending the radio frequency microwave signal to the coupler 2; the coupler 2 is set to be exposed in the air so as to detect the icing and frosting phenomena in the environment and transmit the radio frequency microwave signal generated by the radio frequency microwave signal source; the detector 3 is used for receiving the radio frequency microwave signal transmitted by the coupler 2, detecting the radio frequency microwave signal, converting the energy of the radio frequency microwave signal into a direct current signal and outputting the direct current signal to an external upper computer. It should be noted that the external upper computer may adopt the existing technology, and therefore, detailed description is not provided in the embodiment of the present invention.
Specifically, referring to fig. 2, the radio frequency microwave signal source 1 includes a power supply 10, a field effect transistor 11, and a microstrip resonator 12; a current limiting resistor 13 and a choke capacitor 14 are also provided between the power supply 10 and the field effect transistor 11. In the embodiment of the invention, the radio frequency microwave signal source 1 is constructed by adopting a single separation device, the main separation device is a field effect tube 11, and the microstrip line is used as the microstrip resonator, so that the cost of the whole radio frequency microwave signal source can be greatly reduced, and basically the cost of the field effect tube 11 is mainly the cost of the microstrip line. In some embodiments, the microwave signal source may be an MMIC (monolithic microwave integrated circuit) type, and the field effect transistor, the power supply, the choke capacitor 14 and the current limiting resistor 13 are formed and connected on a semi-insulating semiconductor substrate by a semiconductor process method, so that the volume of the radio frequency microwave signal source can be greatly reduced, and the cost can be reduced. In some embodiments, a dc blocking capacitor 15 is also provided between the microstrip resonator 12 and the coupler 2.
In some embodiments, the coupler 2 is formed by a plurality of microstrip lines 20, the resonant frequency of which is set by the microstrip lines
) (ii) a The multi-section microstrip line 20 is set to be exposed in the air of the tested environment to detect the icing and frosting conditions of the tested environment; when the icing and frosting phenomena occur, ice or frost adheres to the surface of the microstrip line 20, and the resonant frequency of the microstrip line changes at the moment. In the icing and frosting environment and the non-icing and frosting environment, the resonance frequency of the microstrip line is different, so that the signal energy received by the wave detector 3 and transmitted by the radio frequency microwave signal source transmitted by the coupler 2 is changed.
The detector 3 is a passive diode half-wave detection circuit or an active detection circuit. Referring to fig. 3, in the embodiment of the present invention, the detector is a passive diode half-wave detector circuit including a diode D 1 30. Load resistance R load 31 and a capacitor C out 32. Referring to FIG. 4A, diode D 1 30 receives the input signal of the coupler 2, when the input signal is in positive period and the signal amplitude is larger than the voltage V of the diode DC Time, diode tube D 1 30 is in forward conduction; when the input signal is in the negative period, i.e. when the input signal is in the negative voltage, the diode tube D 1 30 is turned off, so that diode D is connected 1 The output of 30 will form a dc bias level proportional to the signal strength, from which it can be determined whether icing and frosting is occurring. For example, in FIG. 4A, S1 represents a periodic signal coupled by the coupler during non-icing and frosting, and the periodic signal is incident on the diode tube D 1 At 30, only the diode D is in the positive period of the periodic signal 1 30 leadBy generating a direct current component, i.e. t 1 -t 2 Time period, corresponding to S1, diode D 1 The signal output by 30 is shown in fig. 4B. S2 is a periodic signal coupled via a coupler when icing and frosting occur, and the periodic signal is at t 1’ -t 2’ The time segments generate a direct current component. Diode D corresponding to S2 1 The signal output by 30 is shown in fig. 4C. As can be seen, according to diode D 1 30, the DC level finally output can detect whether the icing and frosting phenomena occur.
Referring to fig. 2, in some embodiments, the rf microwave signal source 1, the coupler 2, and the detector 3 are disposed on a single PCB 4, wherein the rf microwave signal source 1, the coupler 2, and the detector 3 are disposed on the same surface of the PCB 4, and the other surface of the PCB is tightly attached to a condensation sheet of a measured object, so that the microwave sensor and the condenser can be frosted synchronously, thereby improving the efficiency and accuracy of frosting detection.
In some embodiments, the rf microwave signal source 1 and the detector 3 are respectively disposed at two ends of the PCB 4, and the microstrip line 20 is disposed in the middle of the PCB 4.
In some embodiments, the microstrip line is disposed in a square shape at a position on the PCB 4, and the microstrip line includes a plurality of sections of strip lines attached to the surface of the PCB, and the plurality of sections of strip lines have the same width and thickness. It should be noted that, in some other embodiments, the microstrip line may also be configured in other structural forms, and no particular limitation is imposed in the embodiments of the present invention, and any structural form is not departing from the spirit of the present invention, and the present invention shall fall within the protection scope of the present invention.
The whole microwave sensor product is only built by a plurality of separating devices (a power supply, a field effect tube, a capacitor, a resistor and a diode), the separating devices are arranged on the single PCB, the size of the sensor is small, the cost is low, the sensor can be tightly attached to a condensing sheet of a measured object, the frosting efficiency is high, and the synchronous detection of the icing and frosting of the condenser can be realized.
In the embodiment of the invention, the resonator and the coupler are microstrip lines formed on the PCB, in practical application, the main devices are a field effect tube, a diode, a capacitor and a resistor, the cost of the capacitor, the resistor and the diode is very low, mainly the cost of the field effect tube, and the cost of the whole sensor product can be less than one yuan, so that the cost can be greatly reduced.
Referring to fig. 5 to 6, a microwave sensor-based icing and frosting detection device 5 as another embodiment of the present invention comprises the microwave sensor according to any of the above-mentioned embodiments, a base 50, a sealing sheet 51 and a cover plate 52; wherein, the microwave sensor is integrated on the single PCB board 4; the base 50 is provided with a positioning and fixing column 500, the PCB 4, the sealing sheet 51 and the cover plate 52 are provided with a fixing hole 501 corresponding to the positioning column 500, and the PCB 4, the sealing sheet 51 and the cover plate 52 are fixed on the base 50 through the matching of the fixing hole 501 and the positioning and fixing column 500.
In some embodiments, the sealing plate 51 and the cover plate 52 are provided with a concave opening 502 corresponding to the coupler (microstrip line) of the microwave sensor on the PCB 4, so that the coupler (microstrip line 20) of the microwave sensor is exposed to the measured environment.
In some embodiments, the sealing plate is provided with a square opening 510 corresponding to the rf microwave signal source of the microwave sensor and the position of the detector on the PCB.
In some embodiments, the shape of the sealing plate 51 is substantially the same as the shape of the cover plate 52, and the thickness of the sealing plate 51 is less than the thickness of the cover plate 52.
In the embodiment of the present invention, the icing and frosting detection device is used for detecting the icing and frosting condition of the refrigerator, and it should be understood that the present invention is not limited to the icing and frosting detection of the refrigerator, and the present invention can also be applied to refrigeration equipment such as an air conditioner, and is not particularly limited herein; in any case, the invention should be protected as long as it is the same as the principle scheme of the invention. In the embodiment of the invention, the detected environment is a refrigerator, and the measured physical quantity is the icing and frosting condition of the refrigerator.
It is to be understood that when the sensor of the present invention is embedded in a device or hardware, corresponding structural or component changes may be made to accommodate the needs, the nature of which still employs the sensor of the present invention and, therefore, should be considered as within the scope of the present invention. The foregoing is a further detailed description of the invention in connection with specific/preferred embodiments and it is not intended to limit the invention to the specific embodiments described. It will be apparent to those skilled in the art that various substitutions and modifications can be made to the described embodiments without departing from the spirit of the invention, and these substitutions and modifications should be considered to fall within the scope of the invention. In the description herein, references to the description of the term "one embodiment," "some embodiments," "preferred embodiments," "an example," "a specific example," or "some examples" or the like are intended to 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 are not necessarily intended to 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. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction. Although embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the scope of the invention as defined by the appended claims.
Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. One of ordinary skill in the art will readily appreciate that the above-disclosed, presently existing or later to be developed, processes, machines, manufacture, compositions of matter, means, methods, or steps, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.
Claims (10)
1. A microwave sensor, comprising: the radio frequency microwave signal source, the coupler and the detector are arranged on the single PCB; the radio frequency microwave signal source is used for generating a radio frequency microwave signal and sending the radio frequency microwave signal to the coupler; the coupler is set to be exposed in the air so as to detect the icing and frosting phenomena in the environment and transmit the radio frequency microwave signal generated by the radio frequency microwave signal source; the detector is used for receiving the radio frequency microwave signal transmitted by the coupler, detecting the radio frequency microwave signal to convert the energy of the radio frequency microwave signal into a direct current signal, and outputting the direct current signal to an external upper computer.
2. A microwave sensor as in claim 1, wherein: the microwave signal source comprises a power supply, a field effect tube and a microstrip resonator; wherein, a current limiting resistor and a choke capacitor are also arranged between the power supply and the field effect tube.
3. A microwave sensor as in claim 2, wherein: the microwave signal source is built by adopting a single separating device; the microstrip resonator is a microstrip line formed on a PCB.
4. A microwave sensor as in claim 2, wherein: and a DC blocking capacitor is also arranged between the microstrip resonator and the coupler.
5. A microwave sensor as in claim 1, wherein: the coupler is formed by a plurality of sections of microstrip lines, and the plurality of sections of microstrip lines are arranged to be exposed in the air of the tested environment.
6. A microwave sensor as in claim 1, wherein: the detector includes a diode that receives the input signal of the coupler.
7. A microwave sensor as in claim 1, wherein: the radio frequency microwave signal source, the coupler and the detector are arranged on the same surface of the PCB.
8. A microwave sensor as in claim 7 wherein: the radio frequency microwave signal source and the detector are respectively arranged at two ends of the PCB, and the coupler is arranged in the middle of the PCB.
9. The utility model provides an icing detection equipment that frosts based on microwave sensor which characterized in that: comprising the microwave sensor of any one of claims 1-8, a base, a sealing plate, and a cover plate; the PCB, the sealing sheet and the cover plate correspond to the positioning column, and fixing holes are formed in the positioning column and matched with the fixing holes to fix the PCB, the sealing sheet and the cover plate on the base.
10. A microwave sensor-based icing detection apparatus according to claim 8 wherein: the sealing sheet and the cover plate are provided with concave openings corresponding to the coupler positions of the microwave sensors on the PCB, so that the couplers of the microwave sensors are exposed in the tested environment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210599527.5A CN115015294A (en) | 2022-05-30 | 2022-05-30 | Microwave sensor and icing and frosting detection equipment based on microwave sensor |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210599527.5A CN115015294A (en) | 2022-05-30 | 2022-05-30 | Microwave sensor and icing and frosting detection equipment based on microwave sensor |
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| CN115015294A true CN115015294A (en) | 2022-09-06 |
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| CN202210599527.5A Pending CN115015294A (en) | 2022-05-30 | 2022-05-30 | Microwave sensor and icing and frosting detection equipment based on microwave sensor |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117368232A (en) * | 2023-10-08 | 2024-01-09 | 江苏麦赫物联网科技有限公司 | Miniature ice and water accumulation sensor |
| CN118961763A (en) * | 2024-10-15 | 2024-11-15 | 北京理工大学 | A microwave ice detection device and system based on capacitive coupling splitting ring |
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2022
- 2022-05-30 CN CN202210599527.5A patent/CN115015294A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117368232A (en) * | 2023-10-08 | 2024-01-09 | 江苏麦赫物联网科技有限公司 | Miniature ice and water accumulation sensor |
| CN118961763A (en) * | 2024-10-15 | 2024-11-15 | 北京理工大学 | A microwave ice detection device and system based on capacitive coupling splitting ring |
| CN118961763B (en) * | 2024-10-15 | 2024-12-13 | 北京理工大学 | A microwave ice detection device and system based on capacitive coupling splitting ring |
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