Intelligent temperature, humidity and pressure sensor

Abstract

The utility model discloses an intelligent temperature, humidity and pressure sensor, which is characterized by comprising a shell structure, a connector, a protective cover, an analog board, a main board, a probe board, a pressure sensitive element and an upper cover structure, the analog board, the main board and the pressure sensitive element are accommodated in the shell structure, and the probe board extends out of one end of the shell structure, is in contact with the environment and is used for measuring environment temperature and humidity information; the main board is used for data acquisition and communication control, and the analog board is used for power conversion and analog current driving; the hollow part of the upper cover structure accommodates the connector, and the connector is protected on the opposite side through the protective cover; the pressure sensitive element is used for measuring environment pressure information; the pressure sensitive element and the probe plate output digital signals. Three laser welding connecting parts are arranged at the joint of the shell structure, between the upper cover structure and the shell structure and between the connector and the upper cover structure; and the interior of the shell structure is completely isolated from the external environment through a potting method.

Description

Technical Field

[0001] The utility model belongs to the technical field of sensors, and in particular relates to an intelligent temperature, humidity and pressure sensor. Background Art

[0002] The measurement of temperature, humidity and pressure parameters is not only closely related to daily life, but also widely used in industrial production, weather forecasting, climate analysis, environmental monitoring, aerospace and other fields. Small size, low power consumption, low cost monolithic integrated sensors can meet the requirements of large-scale, one-time use, especially in meteorological one-time use. However, the current temperature, humidity and pressure sensors are less integrated and cannot be compatible with analog and digital quantities at the same time; the sealing structure is too simple to meet the sealing requirements, and the degree of intelligence is not high, which cannot achieve accurate measurement of temperature, humidity and pressure parameters in special application scenarios such as aerospace.

[0003] Therefore, the above-mentioned prior art indeed needs to propose a better solution. Summary of the invention

[0004] The purpose of the utility model is to provide an intelligent temperature, humidity and pressure sensor, the sensor housing has high corrosion resistance, the printed circuit board adopts the form of multiple pieces and is fixed by copper columns to ensure vibration and impact resistance; the whole body adopts laser welding technology, and the Y30D connector is selected as the connector to improve the waterproof and airtight characteristics of the sensor; and digital signals are used to realize the collection and output of environmental information, the collection accuracy and the implementation of intelligent sensing.

[0005] The utility model provides an intelligent temperature, humidity and pressure sensor, characterized in that it comprises: a housing structure (1), a connector (2), a protective cover (3), an analog board (4), a main board (5), a probe board (6), a pressure sensitive element (7) and an upper cover structure (8); wherein:

[0006] The shell structure (1) is an integrally formed stepped structure, which accommodates the simulation board (4), the main board (5) and the pressure sensitive element (7) therein; the probe board (6) extends from one end of the shell structure (1) to contact the environment and is used to measure the temperature and humidity information of the environment; the main board (5) is used for data acquisition and communication control, and the simulation board (4) is used for power conversion and analog current driving;

[0007] The upper cover structure (8) is attached to the side opposite to the housing structure (1) and the probe plate (6); the hollow portion of the upper cover structure (8) accommodates the connector (2), and the connector (2) is protected by a protective cover (3) on the opposite side;

[0008] The pressure sensitive element (7) is arranged between the simulation board (4) and the main board (5) and between the simulation board (4) and the upper cover structure (8) and is used to measure environmental pressure information;

[0009] Wherein, the pressure sensitive element (7) and the probe plate (6) both output digital signals;

[0010] The connection point of the shell structure (1) of the intelligent temperature, humidity and pressure sensor comprises a first laser welding connection part, the upper cover structure (8) and the shell structure (1) comprise a second laser welding connection part, and the connector (2) and the upper cover structure (8) comprise a third laser welding connection part;

[0011] The intelligent temperature, humidity and pressure sensor completely isolates the interior of the housing structure (1) from the external environment by means of potting.

[0012] Preferably, the maximum size of the intelligent temperature, humidity and pressure sensor is φ40mm×69mm.

[0013] Preferably, the mechanical interface of the intelligent temperature, humidity and pressure sensor is M24×15mm.

[0014] Preferably, the pressure sensitive element (7) comprises a head pressure sensitive element (71) and a tail pressure sensitive element (72), wherein the head pressure sensitive element (71) and the probe plate (6) are placed at the front end of the inner cavity of the sensor structure interface to collect temperature, humidity and pressure information in the measured environment; wherein the head pressure sensitive element (71) collects the pressure of the measured environment through the first air vent, and the probe plate (6) is completely exposed to the measured environment to monitor the temperature and humidity information; in order to achieve pressure difference measurement, the tail pressure sensitive element (72) is arranged at the tail of the sensor, and the tail pressure sensitive element (72) collects the pressure of the atmospheric environment through the second air vent; and the collected values ​​of the head pressure sensitive element (71) and the tail pressure sensitive element (72) are subtracted to obtain the measured pressure difference.

[0015] Preferably, the first air hole and the second air hole are both air holes with a diameter of φ2.

[0016] Preferably, two circuit boards are placed inside the housing structure (1) of the sensor, and the two circuit boards are connected to the structure of the sensor by copper columns.

[0017] Preferably, the two circuit boards are connected by copper pillars.

[0018] Preferably, the shell structure (1) is made of 316L stainless steel with Mo element added.

[0019] Preferably, the sensor further includes a power supply circuit for converting external power supply into 5V and 3.3V for use by the sensor, and the power supply circuit includes a power supply electromagnetic suppression and protection circuit and a power conversion circuit; wherein,

[0020] The power supply electromagnetic suppression and protection circuit includes: a diode device to prevent the power supply from being reversely connected, a transient suppression tube to prevent the peak surge from burning out the subsequent circuit; a common mode suppression inductor and matching inductors and capacitors;

[0021] The power conversion circuit is used to convert the external power supply into 5V, and then use the voltage conversion chip to convert 5V into 3.3V for use by the sensor; a two-stage power supply level conversion is used to provide power supply stability.

[0022] Preferably, the connector (2) is a Y30D connector, so that the electronic and electrical modules and components can be connected into a complete system in a short time, wherein Y represents welding and D represents high frequency band.

[0023] The sensor provided by the utility model has the following beneficial technical effects:

[0024] (1) The sensor housing has high corrosion resistance through the combination of 316L stainless steel and Mo materials;

[0025] (2) The printed circuit board is in the form of multiple pieces, and is fixed to itself and other components through copper pillars to ensure vibration and impact resistance;

[0026] (3) The whole body is laser welded, and the Y30D connector is selected as the connector to improve the waterproof and airtight properties of the sensor;

[0027] (4) Use digital signals to collect and output environmental information with high collection accuracy;

[0028] (5) Through the design of software processes, intelligent sensing can be implemented, triggering switching between monitoring mode and detector mode, thereby improving the applicability of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of the sensor body according to a preferred embodiment of the utility model;

[0030] Figure 2 A schematic diagram of the internal structure size and architecture of a sensor according to a preferred embodiment of the utility model;

[0031] Figure 3 It is a schematic diagram of a pressure sensitive element installation scheme according to a preferred embodiment of the utility model;

[0032] Figure 4The figure is a power supply electromagnetic suppression and protection circuit diagram according to a preferred embodiment of the utility model;

[0033] Figure 5 A power conversion circuit diagram according to a preferred embodiment of the utility model;

[0034] Figure 6 It is a schematic diagram of the working principle according to the preferred embodiment of the utility model;

[0035] Figure 7 It is a schematic diagram of a processing circuit design according to a preferred embodiment of the utility model;

[0036] Figure 8 A communication circuit design diagram according to a preferred embodiment of the utility model;

[0037] Fig. 9 A DAC circuit design diagram according to a preferred embodiment of the present utility model is shown;

[0038] Fig.10 It is a design diagram of a current driving circuit according to a preferred embodiment of the utility model;

[0039] Fig.11 A diagram showing a software working mode switching according to a preferred embodiment of the utility model;

[0040] Fig.12 The present invention is a schematic structural diagram of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0042] Embodiment 1

[0043] See also Figure 1 This embodiment provides an intelligent temperature, humidity and pressure sensor, including: a housing structure 1, a connector 2, a protective cover 3, an analog board 4, a main board 5, a probe board 6, a pressure sensitive element 7 and an upper cover structure 8; wherein:

[0044] The shell structure 1 is a stepped structure formed by two hollow cylinders of different diameters, which contain a simulation board 4, a main board 5 and a pressure sensitive element 7. The probe board 6 extends from one end of the shell structure 1 to contact the environment and is used to measure the ambient temperature and humidity information. The main board 5 is used for data acquisition and communication control, and the simulation board 4 is used for power conversion and analog current driving.

[0045] The upper cover structure 8 is attached to the side opposite to the housing structure 1 and the probe plate 6. The hollow part of the upper cover structure 8 accommodates the connector 2, and the connector 2 is protected by the protective cover 3 on the opposite side.

[0046] The pressure sensitive element 7 is arranged between the simulation board 4 and the main board 5 and between the simulation board 4 and the upper cover structure 8 for measuring the environmental pressure information.

[0047] See also Figure 2 , sensor structure design diagram. As a preferred embodiment, the maximum size of the intelligent temperature, humidity and pressure sensor is φ40mm×69mm, and the mechanical interface is M24×15mm.

[0048] As a preferred embodiment, the joints of the shell structure 1 of the intelligent temperature, humidity and pressure sensor are connected by laser welding, the upper cover structure 8 is connected to the shell structure 1 by laser welding, and the connector 2 is connected to the upper cover structure 8 by laser welding. Laser welding is to weld the materials together after melting them at high temperature with laser, without the need for other welding materials. It is characterized by high weld strength, good air tightness, small weld, low heat generation, and no damage to internal devices.

[0049] like Figure 3 As shown, as a preferred embodiment, the pressure sensitive element 7 includes a head pressure sensitive element 71 and a tail pressure sensitive element 72, wherein the head pressure sensitive element 71 and the probe plate 6 are placed at the front end of the inner cavity of the sensor structure interface to collect the temperature, humidity and pressure information in the measured environment; wherein the head pressure sensitive element 71 collects the pressure of the measured environment through a φ2 air vent, and the probe plate 6 is completely exposed to the measured environment to monitor the temperature and humidity information; in order to realize the pressure difference measurement, the tail pressure sensitive element 72 is arranged at the tail of the sensor, and the tail pressure sensitive element 72 collects the pressure of the atmospheric environment through a φ2 air vent; the collected values ​​of the head pressure sensitive element 71 and the tail pressure sensitive element 72 are subtracted to obtain the measured pressure difference.

[0050] In order to meet the measurement requirements of the absolute pressure and gauge pressure inside and outside the sensor, two pressure sensitive elements are selected to measure the internal pressure and external pressure respectively. Pressure measurement requires full contact with the external environment. Considering the airtightness requirements of the sensor as a whole, the pressure sensitive element is encapsulated in the structure as a whole, and the pressure of the measured environment is collected through the φ2 air vent. This ensures that the pressure sensitive element can fully contact the external measurement environment and the overall airtightness of the sensor is guaranteed.

[0051] As a preferred embodiment, the outer dimensions of the sensor are minimized while meeting the technical requirements, and the interior of the housing structure 1 is completely isolated from the external environment by potting. This sealing method can completely eliminate the possibility of leakage, and can enable each component to be mechanically fixed in place, meet the sealing requirements of special applications, and make the measured values ​​more reliable. In addition, the intelligent temperature, humidity and pressure sensor uses a Y30D connector as the connector 2, which has high waterproof and airtight properties, and the reliability is further improved.

[0052] As a preferred embodiment, two circuit boards are placed inside the housing structure 1 of the sensor, and copper columns are used to connect the circuit boards to the structure and between the circuit boards to ensure the ability to resist vibration and impact.

[0053] As a preferred embodiment, the shell structure 1 is made of 316L stainless steel. The structural material has a higher corrosion resistance due to the addition of Mo element.

[0054] The power supply circuit design mainly converts the external power supply into 5V and 3.3V for use by the sensor. The circuit design mainly considers the stability of the power supply, filtering characteristics, protection against reverse connection, and protection against power supply spike surges.

[0055] See also Figure 4 This is a schematic diagram of the sensor power supply electromagnetic suppression and protection circuit, in which a diode device is used to prevent the power supply from being reversed, and a transient suppression tube is used to prevent spike surges from burning out the subsequent circuits. Common-mode suppression inductors and matching inductors and capacitors are used to suppress electromagnetic interference and improve power supply quality and stability.

[0056] See also Figure 5 This is a schematic diagram of the power conversion circuit, in which the external power supply is converted into 5V, and then a voltage conversion chip is used to convert 5V into 3.3V for the sensor. The use of two-stage power supply level conversion can further improve the stability of the power supply.

[0057] See also Figure 6 The working principle diagram of the sensor is shown in Figure 6As shown, the pressure, temperature and humidity sensitive elements selected by the sensor all output digital signals to realize the collection of environmental information. The digital signals output by the tail pressure sensitive element 72 corresponding to the external pressure collection unit of the sensitive element, the head pressure sensitive element 71 corresponding to the internal pressure collection unit, and the probe board 6 corresponding to the internal temperature and humidity collection unit are analyzed and processed by the processor control unit, and the RS-422A communication is controlled to transmit the information to the control end or the host computer; at the same time, the signal conditioning module is controlled to realize the analog current output of the temperature, humidity and pressure parameters. The host computer can control the working mode of the sensor through the RS-422A communication interface and modify the configuration parameters of the sensor. The power conversion module completes the conversion processing of the external power supply to power the sensor.

[0058] (I) Temperature and humidity measurement solution

[0059] Temperature and humidity measurement is achieved by using high-precision temperature and humidity sensitive components. This embodiment uses the SHT31 temperature and humidity sensitive component of Sensirion Company. This component has high temperature and humidity measurement accuracy, good stability, wide measurement range, low power consumption, short response time, and humidity directly outputs 14-bit I2C digital signal

[0060] (II) Pressure measurement scheme

[0061] The pressure measurement is realized by using a high-precision pressure sensitive element 7. In this embodiment, an absolute pressure sensitive core with a rated range of 200kPa is used as the pressure sensitive element. The core has low power consumption. When the power supply voltage is in the range of 1.8V to 3.6V, the power consumption is no more than 10uA. There is no peripheral circuit and it directly outputs a 24-bit I2C digital signal.

[0062] (III) Processor Design

[0063] The processor is the core of the entire sensor and is mainly used for data acquisition, communication control, and signal conversion. Figure 7 The main parameters of the ultra-low power microcontroller processor are as follows:

[0064] Supply voltage: 1.8V~5.5V;

[0065] Maximum operating frequency: 20MHz;

[0066] Internal programmable Flash: 32K;

[0067] Interface resources: serial port, I2C;

[0068] On-chip watchdog;

[0069] Working temperature: -40℃~85℃.

[0070] (IV) Communication design plan

[0071] like Figure 8 The figure shows the design of the communication circuit. The sensor has the ability to communicate with the outside world via RS-422A. The communication circuit converts the level of the serial port communication output by the processor to meet the RS-422A communication level standard. TVS tubes are used to protect the communication lines to prevent static electricity from breaking through the level conversion chip.

[0072] (V) Simulation current design scheme

[0073] Since the temperature, humidity and pressure sensitive elements of the sensor all use data output, a special DAC circuit needs to be designed to convert digital quantities into analog quantities for external output, so that the sensor has three 4mA~20mA current output capabilities. First, the temperature, humidity and pressure information are converted into analog voltage quantities through DAC, and then a constant current source is used to drive the current signal output. Fig. 9 and 10 shown.

[0074] (VI) Adapter cable design

[0075] The sensor needs to be used with adapter cables in monitoring mode. The two adapter cables are digital adapter cable and analog adapter cable.

[0076] (VII) Software Design Plan

[0077] There are two working modes of the sensor, namely monitoring mode and detector mode. Since the monitoring mode transmits temperature, humidity, and pressure information through RS-422A or analog quantity, only data is uploaded, and no data is sent. Therefore, when designing the software, the sensor automatically enters the monitoring mode after the power-on self-test. When the sensor receives the mode switching command from the detector, it switches to the detector mode. The sensor working mode switching process is as follows: Fig.11 shown.

[0078] The utility model also provides a memory storing a plurality of instructions, wherein the instructions are used to implement the method as in the first embodiment.

[0079] like Fig.12 As shown, the utility model also provides an electronic device, including a processor 301 and a memory 302 connected to the processor 301, the memory 302 stores a plurality of instructions, and the instructions can be loaded and executed by the processor so that the processor can execute the measurement method corresponding to the sensor in the first embodiment.

[0080] Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An intelligent temperature, humidity and pressure sensor, characterized in that: include: A housing structure (1), a connector (2), a protective cover (3), an analog board (4), a main board (5), a probe board (6), a pressure sensitive element (7) and an upper cover structure (8); wherein: The shell structure (1) is an integrally formed stepped structure, which accommodates the simulation board (4), the main board (5) and the pressure sensitive element (7) therein; the probe board (6) extends from one end of the shell structure (1) to contact the environment and is used to measure the temperature and humidity information of the environment; the main board (5) is used for data acquisition and communication control, and the simulation board (4) is used for power conversion and analog current driving; The upper cover structure (8) is attached to the side opposite to the housing structure (1) and the probe plate (6); the hollow portion of the upper cover structure (8) accommodates the connector (2), and the connector (2) is protected by a protective cover (3) on the opposite side; The pressure sensitive element (7) is arranged between the simulation board (4) and the main board (5) and between the simulation board (4) and the upper cover structure (8) and is used to measure environmental pressure information; Wherein, the pressure sensitive element (7) and the probe plate (6) both output digital signals; The connection point of the shell structure (1) of the intelligent temperature, humidity and pressure sensor comprises a first laser welding connection part, the upper cover structure (8) and the shell structure (1) comprise a second laser welding connection part, and the connector (2) and the upper cover structure (8) comprise a third laser welding connection part; The intelligent temperature, humidity and pressure sensor completely isolates the interior of the housing structure (1) from the external environment by means of potting.

2. The intelligent temperature, humidity and pressure sensor according to claim 1, characterized in that: The maximum size of the intelligent temperature, humidity and pressure sensor is φ40mm×69mm.

3. The intelligent temperature, humidity and pressure sensor according to claim 1, characterized in that: The mechanical interface of the intelligent temperature, humidity and pressure sensor is M24×15mm.

4. The intelligent temperature, humidity and pressure sensor according to claim 1, characterized in that: The pressure sensitive element (7) comprises a head pressure sensitive element (71) and a tail pressure sensitive element (72), wherein the head pressure sensitive element (71) and the probe plate (6) are arranged at the front end of the inner cavity of the sensor structure interface, and are used to collect temperature, humidity and pressure information in the measured environment; wherein the head pressure sensitive element (71) collects the pressure of the measured environment through the first air vent, and the probe plate (6) is completely exposed to the measured environment to monitor the temperature and humidity information; in order to achieve pressure difference measurement, the tail pressure sensitive element (72) is arranged at the tail of the sensor, and the tail pressure sensitive element (72) collects the pressure of the atmospheric environment through the second air vent; and the collected values ​​of the head pressure sensitive element (71) and the tail pressure sensitive element (72) are subtracted to obtain the measured pressure difference.

5. The intelligent temperature, humidity and pressure sensor according to claim 4, characterized in that: The first air hole and the second air hole are both air holes with a diameter of φ2.

6. The intelligent temperature, humidity and pressure sensor according to claim 1, characterized in that: Two circuit boards are placed inside the housing structure (1) of the sensor, and the two circuit boards are connected to the structure of the sensor by copper columns.

7. The intelligent temperature, humidity and pressure sensor according to claim 6, characterized in that: The two circuit boards are connected by copper pillars.

8. The intelligent temperature, humidity and pressure sensor according to claim 1, characterized in that: The shell structure (1) is made of 316L stainless steel with Mo added.

9. The intelligent temperature, humidity and pressure sensor according to claim 1, characterized in that: The sensor also includes a power supply circuit for converting external power supply into 5V and 3.3V for use by the sensor, and the power supply circuit includes a power supply electromagnetic suppression and protection circuit and a power conversion circuit; wherein, The power supply electromagnetic suppression and protection circuit includes: a diode device to prevent the power supply from being reversely connected, a transient suppression tube to prevent the peak surge from burning out the subsequent circuit; a common mode suppression inductor and matching inductors and capacitors; The power conversion circuit is used to convert the external power supply into 5V, and then use the voltage conversion chip to convert 5V into 3.3V for use by the sensor; a two-stage power supply level conversion is used to provide power supply stability.

10. The intelligent temperature, humidity and pressure sensor according to claim 1, characterized in that: The connector (2) is a Y30D connector.

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