CN210953901U - Humidifier calibration circuit and humidifier - Google Patents
Humidifier calibration circuit and humidifier Download PDFInfo
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- CN210953901U CN210953901U CN201921985410.0U CN201921985410U CN210953901U CN 210953901 U CN210953901 U CN 210953901U CN 201921985410 U CN201921985410 U CN 201921985410U CN 210953901 U CN210953901 U CN 210953901U
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Abstract
The utility model provides a humidifier calibration circuit and a humidifier, relating to the technical field of electronic equipment, wherein the humidifier calibration circuit comprises a humidity sensor, a Bluetooth circuit and a display circuit which are respectively connected with a measurement control circuit; the measurement control circuit comprises a capacitance measurement circuit and a storage circuit which are connected with the signal control and processing circuit; the output end of the capacitance measuring circuit is connected with the first input end of the signal control and processing circuit; the input end of the Bluetooth circuit is connected with the second input end of the signal control and processing circuit; the data output end of the humidity sensor is connected with the input end of the capacitance measuring circuit; the input end of the display circuit is connected with the output end of the signal control and processing circuit. The humidity sensor calibration circuit can realize mass humidity sensor production calibration without additional calibration equipment, thereby saving the production cost; through bluetooth transmission calibration data, realize calibrating a plurality of humidity measuring device simultaneously, promoted calibration efficiency.
Description
Technical Field
The utility model belongs to the technical field of the electronic equipment technique and specifically relates to a humidor calibration circuit and humidor are related to.
Background
The humidity sensors adopted in the existing household humidity measuring instrument are of two types, namely a humidity-sensitive resistor and a humidity-sensitive capacitor, and the two types of sensors need to be accurately calibrated due to the high precision requirement of the humidity sensors. In the prior art, special calibration equipment is needed when the humidity sensor is calibrated, so that the cost of the humidity sensor is increased, and meanwhile, a means for quickly transmitting data of the humidity sensor is also lacked.
SUMMERY OF THE UTILITY MODEL
In view of this, the present invention provides a calibration circuit for a humidity sensor and a humidity sensor, which utilize the resources of a humidity measurement device to realize the mass production calibration of the humidity sensor, and do not need additional calibration resources, thereby saving the production cost; the Bluetooth broadcast protocol is adopted to send and receive the humidity calibration data, a plurality of humidity measurement devices in a workshop can be calibrated simultaneously, the calibration speed is increased, and the shipment speed is accelerated finally.
In a first aspect, an embodiment of the present invention provides a calibration circuit for a humidifier, wherein the calibration circuit for a humidifier includes a humidity sensor, a bluetooth circuit and a display circuit, which are respectively connected to a measurement control circuit;
the measurement control circuit comprises a capacitance measurement circuit and a storage circuit which are connected with the signal control and processing circuit; the output end of the capacitance measuring circuit is connected with the first input end of the signal control and processing circuit; the input end of the Bluetooth circuit is connected with the second input end of the signal control and processing circuit;
the data output end of the humidity sensor is connected with the input end of the capacitance measuring circuit;
the input end of the display circuit is connected with the output end of the signal control and processing circuit.
In some embodiments, the humidity sensor is an uncalibrated capacitive sensor; the capacitance value of the sensor changes with the change of the external environment.
In some embodiments, the display circuit is provided with a display screen for displaying the humidity data sent by the measurement control circuit.
In some embodiments, the measurement control circuit employs an SOC chip of MXM11P63 integrated with a high precision capacitive-to-digital converter.
In some embodiments, the bluetooth circuit employs an MG127 bluetooth transmitting chip.
In some embodiments, the signal control and processing circuit performs humidity calibration using the following equation:
RH＝K×(D-D1)+RH1
in the above formula, RH is the humidity value of the humidifier to be measured; d is the capacitance value of the humidifier to be measured; RH1 is the humidor humidity value in the standard measuring chamber; d1 is the capacitance value of the humidifier in the standard measurement chamber; k is a calibration coefficient.
In some embodiments, the calibration factor K is calculated by the following equation:
in the above formula, K is a calibration coefficient; RH1 is the humidometer humidity value in the first measurement chamber; RH2 is the humidometer humidity value in the second measurement chamber; d1 is the capacitance value of the humidifier in the first measurement chamber; d2 is the capacitance value of the humidifier in the second measurement chamber.
In some embodiments, the humidity value of the humidifier, the capacitance value of the humidifier, and the calibration coefficient are transmitted through a bluetooth circuit.
In some embodiments, the storage circuit is provided with a memory, and the humidity value of the humidifier, the capacitance value of the humidifier, and the calibration coefficient are stored in the memory.
In a second aspect, an embodiment of the present invention provides a humidifier, which includes a housing, a display screen, and a humidifier calibration circuit mentioned in any one of the embodiments of the first aspect.
The embodiment of the utility model provides a following beneficial effect has been brought:
the embodiment of the utility model provides a humidor calibration circuit and humidor, this humidor calibration circuit includes humidity transducer, bluetooth circuit and display circuit that are connected with measurement control circuit respectively; the measurement control circuit comprises a capacitance measurement circuit and a storage circuit which are connected with the signal control and processing circuit; the output end of the capacitance measuring circuit is connected with the first input end of the signal control and processing circuit; the input end of the Bluetooth circuit is connected with the second input end of the signal control and processing circuit; the data output end of the humidity sensor is connected with the input end of the capacitance measuring circuit; the input end of the display circuit is connected with the output end of the signal control and processing circuit. The mass production and calibration of the humidity sensors are realized through the self resources of the humidity sensors, no additional calibration equipment is needed, and the production cost is saved. Moreover, the circuit sends and receives humidity calibration data through the Bluetooth broadcast protocol, a plurality of humidity measurement devices in a workshop can be calibrated simultaneously, calibration efficiency is improved, and the shipment speed is accelerated finally.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
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 embodiments or the technical solutions in the prior art will be briefly described below, and it is obvious that the drawings in the following description are 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 humidifier calibration circuit according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a humidifier according to an embodiment of the present invention.
Icon:
102-measurement control circuitry; 104-a humidity sensor; 106-bluetooth circuitry; 108-a display circuit; 12-signal control and processing circuitry; 14-a capacitance measuring circuit; 16-a storage circuit; 202-a housing; 204-display screen; 206-a humidifier calibration circuit.
Detailed Description
To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and obviously, the described embodiments are some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
A hygrometer is a common measuring device in daily and production processes, and the humidity is represented by absolute humidity, relative humidity, dew point, ratio of humidity to dry gas (weight or volume), and the like. The physical quantity most commonly used in daily life to represent humidity is the relative humidity of air, and it is specified in the metering law that humidity is defined as "the quantity of an object state". The moderation referred to in everyday life is relative humidity, expressed in RH%, for example 55 RH% means that the current relative humidity is 55%.
Common humidity measurement methods are: dynamic methods (double pressure method, double temperature method, split flow method), static methods (saturated salt method, sulfuric acid method), dew point method, dry and wet ball method and electronic sensor method. The existing household humidity measuring instrument adopts an electronic sensor method, the electronic sensor method is used for detecting humidity through a humidity sensor, and the existing humidity sensor is divided into two types, namely a humidity sensitive resistor and a humidity sensitive capacitor. Due to the high accuracy requirements of humidity sensors, accurate calibration of both sensors is required. In the prior art, special calibration equipment is needed when the humidity sensor is calibrated, so that the cost of the humidity sensor is increased, and meanwhile, a means for quickly transmitting data of the humidity sensor is also lacked.
Consider the problem that calibration cost is high in the production process of current humidity measuring apparatu, the utility model aims to provide a hygronom calibration circuit and hygronom, this technique can be applied to in the hygronom production process, describes through specific embodiment below.
In order to facilitate understanding of the present embodiment, a humidifier calibration circuit disclosed in an embodiment of the present invention is first described in detail, a schematic diagram of the control circuit is shown in fig. 1, and the humidifier calibration circuit includes: including a humidity sensor 104, a bluetooth circuit 106, and a display circuit 108, each connected to the measurement control circuit 102.
The data output end of the humidity sensor 104 is connected with the input end of the capacitance measuring circuit 14; the data output end of the humidity sensor 104 is a capacitance variation value, and the capacitance measuring circuit 14 converts the capacitance value into a humidity value according to the capacitance variation value.
An input of display circuit 108 is coupled to an output of signal control and processing circuit 12.
The humidity sensor 104 is a humidity sensor that has not been calibrated, and measures the capacitance or resistance value of the relevant electrical element to realize humidity measurement, and the value of the capacitance changes with the change of the external environment temperature.
The measurement control circuit 102 is a core circuit of the calibration circuit of the humidity sensor, and the signal control and processing circuit 12 included therein can quantize the humidity data in the humidity sensor 104 to obtain a specific humidity value and then perform a correction operation. The corrected data and the related humidity data are stored in the storage circuit 16, and the processed humidity data are displayed through the display circuit 108.
The bluetooth circuit 106 can be used to wirelessly receive data related to humidity calibration through a bluetooth broadcast protocol, thereby implementing calibration of multiple humidity measurement devices at the same time. Because the speed of bluetooth transmission is fast, and the delay is low, and stability is high, and final calibration speed is also faster.
In the above embodiment, the output of the humidity sensor 104 is a capacitance value; the input data of the measurement control circuit 102 is capacitance data of the humidity sensor 104 and wireless data of the bluetooth circuit 106, and the output data of the measurement control circuit 102 is a humidity value, which is transmitted as input data to the display circuit 108.
According to the humidometer calibration circuit, the resource of the circuit accessible humidity sensor realizes the production calibration of large batches of humidity sensors, does not need additional calibration equipment, saves the production cost, and the circuit sends and receives humidity calibration data through the Bluetooth broadcast protocol, can calibrate a plurality of humidity measurement devices in a workshop simultaneously, improves the calibration efficiency, and finally accelerates the shipment speed.
In some embodiments, the humidity sensor 104 is an uncalibrated capacitive sensor; the capacitance value of the sensor changes with the change of the external environment. For example, the humidity sensor can use the capacitance value in the printed circuit board to realize the measurement of the humidity, the printed circuit board contains related metal parts, the capacitance is formed by the interval between the metal parts, and finally the measurement of the humidity is realized.
In some embodiments, the display circuit 108 is provided with a display screen for displaying the humidity data sent from the measurement control circuit 102. The Display screen may be an LCD (Liquid Crystal Display) or LED (Light Emitting Diode) Display device, and the humidity value initiated in the measurement control circuit 102 is displayed by the Display device in the Display circuit 108.
In some embodiments, the measurement control circuit 102 employs an SOC chip of MXM11P63 integrated with a high precision capacitive-to-digital converter. The measurement control circuit 102 may be implemented by a related integrated high-precision capacitance-to-digital converter chip, or by another integrated chip for measurement of a related temperature/humidity sensor. In particular, an SOC chip of type MXM11P63, which is commonly used in temperature and humidity sensors and capacitive sensors, may be used.
In some embodiments, the bluetooth circuitry 106 employs an MG127 bluetooth transmitter chip. The relevant bluetooth module in the bluetooth circuit 106 adopts bluetooth 4.0 protocol, can also select the bluetooth protocol of other editions according to actual conditions, MG127 bluetooth emission chip adopts bluetooth 4.0 protocol, bluetooth 4.0 intersects in bluetooth 3.0, promote obviously from aspects such as transmission distance, energy consumption performance and transmission stability, and compare with the latest bluetooth 5.0 at present, its chip cost is far lower than the chip of other bluetooth 5.0 editions, therefore can select MG127 bluetooth emission chip or similar chip preferentially.
In some embodiments, the signal control and processing circuit 12 performs humidity calibration according to the following equation:
RH＝K×(D-D1)+RH1
in the above formula, RH is the humidity value of the humidifier to be measured; d is the capacitance value of the humidifier to be measured; RH1 is the humidor humidity value in the standard measuring chamber; d1 is the capacitance value of the humidifier in the standard measurement chamber; k is a calibration coefficient.
Through the above formula, the humidity value under the humidity environment to be measured can be realized through the measured humidity value RH1 and the capacitance value D1 in the standard measuring chamber in combination with the calibration coefficient K. The calibration factor K in this equation is a ratio that is referenced to the relative humidity and capacitance values in the standard measurement chamber.
In some embodiments, the calibration factor K is calculated by the following equation:
in the above formula, K is a calibration coefficient; RH1 is the humidometer humidity value in the first measurement chamber; RH2 is the humidometer humidity value in the second measurement chamber; d1 is the capacitance value of the humidifier in the first measurement chamber; d2 is the capacitance value of the humidifier in the second measurement chamber.
At least one of the first measuring chamber and the second measuring chamber in the above formula is required to be used as a standard measuring chamber, and the ratio of the obtained humidity difference to the humidity value is used as a calibration coefficient, so that the method can be used for the calibration process of other humidifiers to be measured.
The hygrometer in this embodiment is calibrated by measuring the humidity in the production plant, and the calibration coefficient required for calibration can be calculated using the humidity values and capacitance values of the humidifiers in different plants, and the calculation formula used for calculation can use the calibration coefficient calculation formula.
Specifically, the humidity meter calibration circuit is firstly placed in a first production workshop, and the humidity value RH1 of the workshop is recorded, wherein the measurement precision of the humidity value RH1 is not necessarily accurate and can be changed, because the humidity meter is not calibrated yet at the moment. During the measurement, the capacitance value of the humidity sensor 104 is measured and calculated by the capacitance measurement circuit 14, so as to obtain a capacitance value D1.
After the measurement is finished in the first production workshop, the humidity controller control circuit is placed in the second production workshop, and the humidity RH2 of the second production workshop needs to meet the conditions that RH2> RH1+ 10%, namely, the humidity difference is 10%, so that the precision of the calibration coefficient can be ensured. Then, humidity value RH2 and capacitance value D2 were recorded. After the humidity values and the capacitance values of the two workshops are obtained, the calibration coefficient can be obtained through a calibration coefficient formula.
In some embodiments, the humidity value of the humidifier, the capacitance value of the humidifier, and the calibration coefficient are transmitted through a bluetooth circuit.
The bluetooth circuit 106 receives the humidity value, the capacitance value and the calibration coefficient transmitted from the outside in a bluetooth broadcasting manner. Because the bluetooth agreement is wireless connection, has connection speed fast moreover, characteristics such as transmission stability can calibrate a plurality of humidifiers. The advantage of using the broadcast function of the bluetooth to receive the calibration data is that no wired connection is needed, and the production is convenient; in addition, connection and transmission are not needed, the transmission speed is high, and the production efficiency is high.
In some embodiments, the storage circuit 16 is provided with a memory, and the humidity value of the humidifier, the capacitance value of the humidifier, and the calibration coefficient are stored in the memory.
The humidity value of the humidifier, the capacitance value of the humidifier, and a part of the calibration coefficient are collected or obtained by the signal control and processing circuit 12 in the measurement control circuit 102, and can also be received and obtained by the bluetooth circuit 106 in a bluetooth broadcasting manner, and the obtained humidity value of the humidifier, the capacitance value of the humidifier, and the calibration coefficient are all stored in the memory in the storage circuit 16. When data is required to be extracted during calibration, the required data can be directly retrieved through a memory in the storage circuit 16.
According to the embodiment, the calibration circuit of the humidifier comprises a humidity sensor, a Bluetooth circuit and a display circuit which are respectively connected with a measurement control circuit, wherein the measurement control circuit comprises a capacitance measurement circuit and a storage circuit which are connected with a signal control and processing circuit, the output end of the capacitance measurement circuit is connected with the first input end of the signal control and processing circuit, the input end of the Bluetooth circuit is connected with the second input end of the signal control and processing circuit, the data output end of the humidity sensor is connected with the input end of the capacitance measurement circuit, and the input end of the display circuit is connected with the output end of the signal control and processing circuit. The mass production and calibration of the humidity sensors are realized through the self resources of the humidity sensors, no additional calibration equipment is needed, and the production cost is saved. Moreover, the circuit sends and receives humidity calibration data through the Bluetooth broadcast protocol, a plurality of humidity measurement devices in a workshop can be calibrated simultaneously, calibration efficiency is improved, and the shipment speed is accelerated finally.
The embodiment of the present invention provides a humidifier, as shown in fig. 2, the humidifier includes a housing 202, a display screen 204 and a humidifier calibration circuit 206 mentioned in the above embodiments.
The principle and the technical effect of the humidity sensor mentioned in the embodiment of the present invention are the same as those of the embodiment of the humidity sensor calibration circuit mentioned above, and for the sake of brief description, the embodiment is not mentioned, and reference may be made to the corresponding contents in the embodiment of the method mentioned above.
In the description of the embodiments of the present invention, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Finally, it should be noted that: the above embodiments are only specific embodiments of the present invention, and are not intended to limit the technical solution of the present invention, and the protection scope of the present invention is not limited thereto, although the present invention is described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: those skilled in the art can still modify or easily conceive of changes in the technical solutions described in the foregoing embodiments or make equivalent substitutions for some technical features within the technical scope of the present disclosure; such modifications, changes or substitutions do not substantially depart from the spirit and scope of the embodiments of the present invention, and are intended to be included within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (10)
1. A humidity device calibration circuit is characterized in that the circuit comprises a humidity sensor, a Bluetooth circuit and a display circuit which are respectively connected with a measurement control circuit;
the measurement control circuit comprises a capacitance measurement circuit and a storage circuit which are connected with the signal control and processing circuit; the output end of the capacitance measuring circuit is connected with the first input end of the signal control and processing circuit; the input end of the Bluetooth circuit is connected with the second input end of the signal control and processing circuit;
the data output end of the humidity sensor is connected with the input end of the capacitance measuring circuit;
and the input end of the display circuit is connected with the output end of the signal control and processing circuit.
2. The humidifier calibration circuit according to claim 1, wherein the humidity sensor is an uncalibrated capacitive sensor; the capacitance value of the sensor changes with the change of the external environment.
3. The humidifier calibration circuit according to claim 1, wherein a display screen is disposed in the display circuit for displaying the humidity data sent from the measurement control circuit.
4. The humidifier calibration circuit according to claim 1, wherein the measurement control circuit employs a SOC chip of MXM11P63 integrated with a high precision capacitive-to-digital converter.
5. The humidifier calibration circuit according to claim 1, wherein the bluetooth circuit employs an MG127 bluetooth transmitter chip.
6. The humidifier calibration circuit according to claim 1, wherein the signal control and processing circuit performs humidity calibration using the following equation:
RH＝K×(D-D1)+RH1，
in the above formula, RH is the humidity value of the humidifier to be measured; d is the capacitance value of the humidifier to be measured; RH1 is the humidity value of the humidifier in the standard measurement chamber; d1 is the capacitance value of the humidifier in the standard measurement chamber; k is a calibration coefficient.
7. The humidifier calibration circuit according to claim 6, wherein the calibration coefficient K is calculated by the following equation:
in the above formula, K is a calibration coefficient; RH1 is the humidity value of the humidifier in the first measurement chamber; RH2 is the humidity value of the humidifier in the second measurement chamber; d1 is the capacitance value of the humidifier in the first measurement chamber; d2 is the capacitance value of the humidifier in the second measurement chamber.
8. The humidifier calibration circuit according to claim 7, wherein the humidifier humidity value, the humidifier capacitance value and the calibration coefficient are transmitted through a Bluetooth circuit.
9. The humidifier calibration circuit according to claim 7, wherein a memory is provided in the storage circuit, and the humidity value of the humidifier, the capacitance value of the humidifier, and the calibration coefficient are stored in the memory.
10. A humidometer comprising a housing, a display screen and a humidometer calibration circuit according to any one of claims 1 to 9.
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| CN201921985410.0U CN210953901U (en) | 2019-11-15 | 2019-11-15 | Humidifier calibration circuit and humidifier |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112578840A (en) * | 2020-12-09 | 2021-03-30 | 杭州米芯微电子有限公司 | Method, system and storage medium for calibrating reference voltage by using temperature |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112578840A (en) * | 2020-12-09 | 2021-03-30 | 杭州米芯微电子有限公司 | Method, system and storage medium for calibrating reference voltage by using temperature |
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