CN113671119A

CN113671119A - Gas detection device and temperature compensation method thereof

Info

Publication number: CN113671119A
Application number: CN202110882436.8A
Authority: CN
Inventors: 侯斐; 王建科; 郑宏霏; 董汉
Original assignee: Draeger Safety Equipment China Co ltd
Current assignee: Draeger Safety Equipment China Co ltd
Priority date: 2021-08-02
Filing date: 2021-08-02
Publication date: 2021-11-19

Abstract

A gas detection device and a temperature compensation method thereof, the gas detection device comprising: the sensor module comprises a sensor unit for detecting the VOC concentration of the gas to be detected and generating a detection result; wherein the sensor unit includes: the sensor is used for detecting the VOC concentration of the gas to be detected and generating detection data; a processing unit in communication with the sensor, the processing unit receiving the detection data and processing to generate the detection result; and the temperature compensation unit is used for controlling the temperature of the gas to be measured flowing through the sensor within a preset temperature range. According to the scheme of the invention, the influence of humidity on the detection result can be eliminated in a manner of intervention in advance, so that the detection precision of the gas detection device is improved.

Description

Gas detection device and temperature compensation method thereof

Technical Field

The invention relates to the technical field of gas detection, in particular to a gas detection device and a temperature compensation method thereof.

Background

In the industrial field, toxic and harmful gases such as Volatile Organic Compounds (VOC) can be generated in both raw materials and by-products generated in various steps of the production process, and the toxic and harmful gases can cause great harm to human bodies and even seriously endanger life. Therefore, gas detection devices are used in industry to detect the concentration of VOC in industrial production environment, so as to find out the leakage of toxic and harmful gases in time for prevention and remedy.

The gas detection device monitors toxic and harmful gases by detecting the concentration of VOC (volatile organic compounds) in the gases by using a sensor. The sensors adopted in the existing gas detection device are generally very sensitive to temperature and humidity, and if more water vapor is carried by gas flowing into the gas detection device, the detection result of the sensors can be influenced.

Disclosure of Invention

The invention solves the technical problem of how to eliminate the influence of humidity on the detection result of the gas detection device, thereby improving the detection precision.

In order to solve the above technical problem, an embodiment of the present invention provides a gas detection apparatus, including: the sensor module comprises a sensor unit for detecting the VOC concentration of the gas to be detected and generating a detection result; wherein the sensor unit includes: the sensor is used for detecting the VOC concentration of the gas to be detected and generating detection data; a processing unit in communication with the sensor, the processing unit receiving the detection data and processing to generate the detection result; and the temperature compensation unit is used for controlling the temperature of the gas to be measured flowing through the sensor within a preset temperature range.

Optionally, the temperature compensation unit includes: the temperature measuring unit is communicated with the processing unit and is used for detecting the temperature of the gas to be measured flowing through the sensor and sending a temperature measuring result to the processing unit; and the temperature adjusting unit is arranged around the sensor and is communicated with the processing unit so as to receive a temperature adjusting instruction of the processing unit and execute temperature adjusting operation according to the temperature adjusting instruction, and the temperature adjusting instruction is generated when the temperature measuring result exceeds a preset temperature range.

Optionally, the temperature measuring unit is disposed near an air inlet for conveying the gas to be measured to the sensor.

Optionally, the sensor module further includes a gas collecting member, a gas chamber for accommodating the gas to be detected is disposed on one side of the gas collecting member facing the sensor unit, the sensor is at least partially exposed to the gas chamber, and a projection of the temperature measuring unit on the gas collecting member falls into the gas chamber.

Optionally, the sensor unit includes a housing having a cavity for accommodating the sensor, and the temperature adjustment unit is attached to a sidewall of the cavity and extends along a circumferential direction of the cavity.

Optionally, the temperature adjusting unit is in a strip shape and surrounds the circumferential direction of the chamber to form a closed structure end to end.

Optionally, the number of the temperature adjusting units is multiple and is distributed in multiple positions of the sensor.

Optionally, the temperature adjustment unit is made of a graphene material.

Optionally, along the height direction of the gas detection device, the height of the temperature adjustment unit is equal to the height of the sensor.

Optionally, the preset temperature range is a local section within the range of the span temperature of the sensor.

Optionally, the gas detection apparatus further comprises: and the transmitter module is detachably connected with the sensor module and is used for receiving the detection result and transmitting the detection result outwards.

Optionally, the sensor module further includes: and the pump assembly is detachably connected with the sensor unit, and the gas to be detected is sucked into the sensor module by the pump assembly and is discharged by the pump assembly after flowing through the sensor unit.

In order to solve the above technical problem, an embodiment of the present invention further provides a temperature compensation method for a gas detection apparatus, where the gas detection apparatus includes a sensor for detecting a VOC concentration of the gas to be detected and generating detection data, and the method includes: acquiring a temperature measurement result, wherein the temperature measurement result is the temperature of the gas to be measured flowing through the sensor; judging whether the temperature measurement result exceeds a preset temperature range or not; and when the judgment result shows that the temperature measurement result exceeds the preset temperature range, adjusting the temperature of the gas to be measured flowing through the sensor.

Optionally, the gas detecting device includes a temperature adjusting unit disposed around the sensor, and the adjusting the temperature of the gas to be detected flowing through the sensor includes: and sending a temperature adjusting instruction, wherein the temperature adjusting instruction is used for instructing the temperature adjusting unit to execute temperature adjusting operation.

Optionally, the determining whether the temperature measurement result exceeds the preset temperature range includes: comparing whether the single temperature measurement result exceeds a preset temperature range or not; and/or predicting whether the trend of exceeding the preset temperature range exists according to the change trend of a plurality of temperature measurement results acquired within a period of time.

Optionally, the temperature compensation method further includes: continuously acquiring a temperature measurement result during temperature adjustment; and when the temperature measurement result shows that the temperature of the gas to be measured returns to the preset temperature range, stopping regulating the temperature of the gas to be measured flowing through the sensor.

Compared with the prior art, the technical scheme of the embodiment of the invention has the following beneficial effects:

an embodiment of the present invention provides a gas detection apparatus, including: the sensor module comprises a sensor unit for detecting the VOC concentration of the gas to be detected and generating a detection result; wherein the sensor unit includes: the sensor is used for detecting the VOC concentration of the gas to be detected and generating detection data; a processing unit in communication with the sensor, the processing unit receiving the detection data and processing to generate the detection result; and the temperature compensation unit is used for controlling the temperature of the gas to be measured flowing through the sensor within a preset temperature range.

Compared with the post compensation scheme adopted by the prior art, the embodiment can improve the detection precision of the gas detection device in a mode of intervention in advance, prevent the sensor from dewing in advance, and accordingly eliminate the influence of humidity on the detection result of the sensor. Furthermore, what this embodiment was adjusted based on the temperature compensation unit is the temperature of the gas that awaits measuring, can eliminate the steam that the gas that awaits measuring carried more effectively to reduce the influence of the humidity of the gas that flows into the sensor module to the sensor as far as possible.

Furthermore, the temperature of the gas to be measured is controlled within the preset temperature range through the temperature compensation unit, so that the processing unit can only store the preset calibration curve corresponding to the preset temperature range (such as a room temperature range), and does not need to store calibration data of the full range of the sensor, thereby effectively reducing the data storage burden of the processing unit.

Drawings

FIG. 1 is a schematic structural diagram of a gas detection apparatus according to an embodiment of the present invention;

FIG. 2 is an exploded view of the gas detection apparatus of FIG. 1;

FIG. 3 is a flow chart of a lock control method for a gas detection device according to an embodiment of the present invention;

FIG. 4 is an exploded view of the sensor unit of FIG. 2;

FIG. 5 is a flow chart of a method of temperature compensation for a gas detection device according to an embodiment of the present invention;

FIG. 6 is a cross-sectional view of the transmitter module of FIG. 1 taken along the A-A direction;

FIG. 7 is an exploded view of the pump assembly of FIG. 2;

FIG. 8 is a schematic view of the air-collecting member of FIG. 7;

FIGS. 9 through 11 are schematic views of the air path structure in the sensor module of FIG. 1;

FIG. 12 is a schematic view of a variation of the air passage structure shown in FIGS. 9-11;

in the drawings:

1-a gas detection device; 2-a sensor module; 21-a threaded portion; 211-a clamping portion; 22-a sensor unit; 221-a sensor; 222-a temperature compensation unit; 223-a temperature measuring unit; 224-a temperature adjustment unit; 225-shell; 226-a chamber; 227-an adaptation portion; 228-a processing unit; 229-a signal adjustment unit; 23-a pump assembly; 231-a snap-fit portion; 232-a pump; 232 a-air pump inlet; 232 b-air pump exhaust port; 233-gas collecting member; 234-a body portion; 234 a-wall; 234 b-annular groove; 234 c-quick connect end; 235-air chamber; 236-air inlet; 237-air outlet; 238-a drainage groove; 239-a groove; 24-a housing; 241-air outlet holes; 242-air intake; 243-first intake line; 244-outlet line; 245-gas distribution plate; 246 a-inlet airway; 246 b-outlet airway; 247-a sealing mechanism; 248 — a second air intake conduit; 249-waterproof permeable membranes; 25-a cover portion; 261-foam cotton; 262-sensor end cap; 263-aviation plug; 264-secondary vent line; 265-a limit pin; 266-check valve ball; 3-a transmitter module; 31-a coupling part; 32-a display unit; 321-a display panel; 33-a control unit; 34-a terminal unit; 341-first terminal; 342-a second terminal; 343-a third terminal; 344-a fourth terminal; 35-a communication module; 36-a body; 361-upper cover; 362-a support; 37-a cable passing portion; 371-cable fixing part; z-the height direction of the gas detection device; y-the first direction.

Detailed Description

As background art, a sensor used in an existing gas detection device is very sensitive to temperature and humidity, and a detection result of the sensor is greatly affected by the gas humidity.

In order to eliminate the influence of the temperature and humidity on the detection result, the prior art generally adopts post compensation. Specifically, the detection result of the sensor is compensated according to a preset calibration curve, for example, the detection result is corrected to eliminate the interference of the temperature and the humidity on the detection precision of the sensor.

However, there are many unreasonable points in such a post-compensation manner, such as actually not really eliminating the interference of the temperature and humidity to the sensor, and for example, causing a steep increase in data processing amount of the sensor, and further, if a large amount of calibration data needs to be stored, a large data storage pressure is caused to the gas detection device.

Accordingly, there is a need to provide an improved gas detection device and temperature compensation scheme.

The embodiment can improve the detection precision of the gas detection device in a mode of intervening in advance, prevent the sensor from dewing in advance, and accordingly eliminate the influence of humidity on the detection result of the sensor. Furthermore, what this embodiment was adjusted based on the temperature compensation unit is the temperature of the gas that awaits measuring, can eliminate the steam that the gas that awaits measuring carried more effectively to reduce the influence of the humidity of the gas that flows into the sensor module to the sensor as far as possible.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

FIG. 1 is a schematic structural diagram of a gas detection apparatus according to an embodiment of the present invention; fig. 2 is an exploded view of the gas detecting device shown in fig. 1.

The present embodiment can be applied to a toxic and harmful gas detection scenario, such as the aforementioned scenario in the industrial field. The gas detection device may be a stationary device, i.e., fixedly installed at a specific location in the environment to be detected to detect the toxic gas in the environment to be detected. For example, the gas detection device may be mounted on and communicated into a gas delivery pipeline to detect the concentration of toxic and harmful gases in the gas delivered in the pipeline. For another example, a gas detection device may be installed near a gas delivery line to detect whether a leak has occurred in the gas delivered in the line. Further, the gas detecting device may be a Photo Ion Detector (PID), or a detecting device that detects toxic and harmful gases by using other technical means.

Specifically, with reference to fig. 1 and fig. 2, the gas detection apparatus 1 according to the present embodiment may include: a sensor module 2 for detecting the VOC concentration of the gas to be detected and sending the detection result; and a transmitter module (transmitter) 3 detachably connected with the sensor module 2, wherein the transmitter module 3 is used for receiving the detection result and transmitting the detection result outwards. The gas to be detected (also referred to as a sampling gas) may be collected from an environment to be detected in which the gas detection device 1 is located.

More specifically, the detection result is used to characterize the concentration of VOC in the gas to be measured, i.e., the concentration value of VOC in the gas to be measured. The sensor module 2 can detect the VOC concentration of the gas to be detected, process the detection data to obtain a detection result, and output the detection result to the transmitter module 3 in the form of a digital signal. According to the detection result (i.e. the concentration of VOC), whether toxic gas exists in the environment to be detected or not can be measured, and the content of the corresponding toxic gas can be measured.

Further, transmitter module 3 can transmit, store and display the detection results received from sensor module 2. For example, transmitter module 3 may be provided with a display unit 32 to present the received detection results in real time. For another example, the control unit 33 of the transmitter module 3 can determine whether the VOC content in the gas to be measured exceeds a preset warning value according to the level of the received concentration value. If it is determined that the preset alarm value is exceeded, the control unit 33 may control an alarm unit (not shown) of the transmitter module 3 to issue an alarm. For example, the alarm unit may include an LED lamp disposed on an outer surface of the transmitter module 3, and the LED lamp may blink when the concentration of VOC in the gas to be measured is detected to exceed a standard.

Further, there may be an electrical and mechanical connection between transmitter module 3 and sensor module 2, sensor module 2 obtaining electrical support from transmitter module 3 (or from outside via transmitter module 3) through the electrical connection with transmitter module 3 and transmitting data with transmitter module 3, transmitter module 3 and sensor module 2 being secured to each other through the mechanical connection. In this implementation, the detachable connection between transmitter module 3 and sensor module 2 includes a detachable connection at the mechanical connection level, and also includes a detachable connection at the electrical connection level. The sensor module 2 can be detached from the transmitter module 3 by means of a detachable mechanical connection so that the gas detection device 1 is separated into two separate parts, or mounted to the transmitter module 3 to obtain a complete gas detection device 1. When sensor module 2 is removed from transmitter module 3, the electrical connections of sensor module 2 and transmitter module 3 are simultaneously disconnected, and when sensor module 2 is installed in transmitter module 3, the electrical connections of the two are simultaneously connected.

For example, the sensor module 2 has a generally cylindrical housing (shown). Along the height direction (indicated by the z direction in the drawing) of the gas detection device 1, a transmitter module 3 is provided at the upper end of the sensor module 2. The upper end of the sensor module 2 may be provided with a threaded portion 21, the threaded portion 21 being disposed around the central axis of the cylinder. The lower end of the transmitter module 3 may be provided with a matching coupling 31 (as shown in fig. 6). The threaded portion 21 has an external thread and the coupling portion 31 has a matching internal thread (the specific internal thread is not shown in fig. 6). The mechanical connection between the sensor module 2 and the transmitter module 3 is realized by the threaded portion 21 and the coupling portion 31. Of course, the mechanical connection between the sensor module 2 and the transmitter module 3 can also be realized by means of a snap or a pin, etc.

The electrical connection may be made, for example, by an air plug 263 (as shown in fig. 4). Specifically, a plurality of harness through holes may be provided in the aviation plug 263 to allow harnesses such as a data line, a power line, and a control line to pass through, respectively, and these harnesses are connected to the sensor module 2 and the transmitter module 3, respectively, to achieve electrical connection. The data line is used for transmitting data, such as detection results. The control line is used for transmitting a control signal of the transmitter module 3 to the sensor module 2, such as a start instruction and a stop instruction for controlling whether the sensor 221 in the sensor module 2 works, a heating instruction, and the like, and also such as a start instruction and a stop instruction for controlling whether the pump assembly 23 in the sensor module 2 works.

During assembly, each harness having one end coupled to the transmitter module 3 is inserted into the sensor module 2 from the corresponding harness through hole, and the other end of each harness is coupled to a corresponding component (e.g., a sensor unit 22 described below) in the sensor module 2, thereby achieving electrical connection. Then, the screw part 21 is screwed to the coupling part 31 to achieve mechanical connection of the sensor module 2 and the transmitter module 3. Further, a clamping portion 211 may be formed by machining from the upper end of the sensor module 2 to the first step downward for fixing a jig at the time of assembly, so that a user can conveniently mount the sensor module 2 to the transmitter module 3 using the jig.

Therefore, modularization of the gas detection device 1 can be achieved, a user can flexibly replace any module according to needs without replacing the whole device, and product universality is improved. Specifically, the gas detection function and the data transmission function are functionally modularized into the sensor module 2 and the transmitter module 3 which are independent, and are detachably connected so that either one of them can be independently replaced. A user can choose to use one transmitter module 3 to match with a plurality of sensor modules 2, or can purchase a plurality of sets of gas detection devices 1, and the sensor module 2 and the transmitter module 3 of each gas detection device 1 can be used in a replacement and matching mode.

Further, with continued reference to fig. 1 and 2, the sensor module 2 may include: a sensor unit 22 for generating the detection result, the sensor unit 22 being in communication with the transmitter module 3 for sending the detection result to the transmitter module 3. For example, data lines and control lines are coupled between the sensor unit 22 and the transmitter module 3 for transmission of detection results and control signals. Further, the sensor unit 22 is coupled to a power line to obtain power required for operation, and the other end of the power line may be coupled to the transmitter module 3 or coupled to the outside of the gas detection apparatus 1 through a cable passing portion 37 provided in the transmitter module 3.

Further, with continued reference to fig. 1 and 2, the sensor module 2 may further include: a pump assembly 23 detachably connected to the sensor unit 22, wherein the gas to be measured is sucked into the sensor module 2 by the pump assembly 23 and discharged by the pump assembly 23 after passing through the sensor unit 22.

In this implementation, the detachable connection between the pump assembly 23 and the sensor unit 22 includes a detachable connection of a mechanical connection level and an electrical connection level. The pump assembly 23 can be detached from the sensor unit 22 by means of a detachable mechanical connection so that both components in the sensor module 2 can also be replaced at will, or mounted to the sensor unit 22 to obtain a complete sensor module 2. The electrical connection between the pump assembly 23 and the sensor unit 22 is synchronously broken when the pump assembly 23 is removed from the sensor unit 22, and is synchronously connected when the pump assembly 23 is mounted to the sensor unit 22.

Further, the electrical connection between the pump assembly 23 and the sensor unit 22 is such that the pump assembly 23 is directly or indirectly coupled to a power supply line to obtain the power required for operation. The electrical connection between the two also couples the pump assembly 23, either directly or indirectly, to the control line to receive start or stop commands.

For example, referring to fig. 2, the pump assembly 23 may be located below the sensor unit 22 in the height direction (the illustrated z direction) of the gas detection apparatus 1, and the gas to be measured is sucked by the pump assembly 23 and flows to the sensor unit 22 from below to above in the z direction. The gas to be measured flowing through the sensor unit 22 is driven by the pump assembly 23 to be discharged out of the sensor module 2 from top to bottom in the direction opposite to the z-direction.

That is, in the present embodiment, the gas to be measured enters from the lower end of the gas detection device 1 in the height direction (the illustrated z direction), and is discharged from the lower end, and the gas path through which the gas to be measured flows is limited to the chamber 226 of the sensor module 2 for accommodating the sensor unit 22 and the part (such as the pump assembly 23) below the chamber 226 in the z direction, while the part of the sensor unit 22 above the chamber 226 in the z direction and the transmitter module 3 have no gas path therein. Wherein the area below the chamber 226 in the z-direction is adapted to form a measurement space in which the gas to be measured continuously flows and is detected by the sensor unit 22.

From this, thereby sensor module 2 is integrated with pump assembly 23 and realizes that the pump is inhaled formula and is surveyed, and the pump assembly 23 of just being integrated in sensor module 2 makes the gas circuit restriction that the gas that awaits measuring flows in gaseous detection device 2 inside sensor module 2, and is irrelevant with changer module 3 to effectively shorten gas circuit length, do benefit to the response speed that improves gaseous detection device 1. Further, need not to set up the structure of breathing in such as air pump in addition outside gas detection device 1, and gas detection device 1 overall structure is small and exquisite for gas detection device 1 is more nimble in the position that sets up of treating in the detection environment, if can fix in the narrow and small space between gas pipeline.

Further, inside the sensor module 2, the gas detection function and the gas flow direction control function are also functionally modularized as the sensor unit 22 and the pump assembly 23, and both are also detachably connected so that either one may be individually replaced. For example, different sensor units 22 can be provided with gas-sensitive devices for different gases, so that different types of toxic and harmful gases can be detected, and the sensor units 22 can be replaced individually as required, while the transmitter module 3 and the pump assembly 23 do not need to be replaced, and the original components can still be used, so that the compatibility and the universality of the transmitter module 3 and the pump assembly 23 can be improved, and the maintenance is also convenient.

In one implementation, the gas detection apparatus 1 may include: an identity matching unit (not shown) in communication with the transmitter module 3 and the sensor unit 22, the identity matching unit being configured to obtain and match first identity information of the transmitter module 3 and second identity information of the sensor unit 22; and a connection control unit (not shown) in communication with the identity matching unit, the connection control unit being configured to control a connection state of the sensor module 2 and the transmitter module 3 according to a matching result of the identity matching unit.

Fig. 3 shows a flowchart of a lock control method for the gas detection apparatus 1 according to an embodiment of the present invention. The locking control method can be executed by the identity matching unit and the connection control unit in cooperation to realize locking control between the sensor unit 22 and the transmitter module 3.

Specifically, referring to fig. 3, the lock control method for the gas detection apparatus 1 according to the present embodiment includes the steps of:

step S301, acquiring and pairing first identity information of the transmitter module 3 and second identity information of the sensor unit 22;

step S302, controlling the connection state of the sensor module 2 and the transmitter module 3 according to the pairing result.

More specifically, the first identity information may be an identity generated from a series of parameters of the transmitter module 3 that is capable of uniquely identifying the transmitter module 3. Similarly, the second identity information may be an identity generated from a series of parameters of the sensor unit 22 that is capable of uniquely identifying the sensor unit 22. The first identity information and the second identity information may be stored in a storage module of the corresponding device, respectively.

Further, the identity pairing unit and the connection control unit may be integrated in the control unit 33 of the transmitter module 3 (as shown in fig. 2) or in the processing unit 228 of the sensor unit 22 (as shown in fig. 4). Alternatively, the identity pairing unit and the connection control unit may be modules/chip modules independent of the aforementioned control unit 33 or processing unit 228.

Further, the connection status may include a connection success status and a connection failure status. In the successful connection state, the sensor unit 22 connected to the transmitter module 3 can normally operate, for example, perform gas detection and send a detection result to the transmitter module 3. In the connection failure state, although the sensor unit 22 has an electrical connection and a mechanical connection with the transmitter module 3, the sensor unit 22 cannot normally operate, for example, the control command of the transmitter module 3 is limited and cannot be successfully transmitted to the sensor unit 22, or the sensor unit 22 is disabled and cannot respond to the control command.

Further, the gas detection apparatus 1 may further include a pairing information storage unit (not shown) in communication with the identity pairing unit, wherein the pairing information storage unit is configured to store at least one first identity information, at least one second identity information, and a pairing relationship thereof. The pairing information storage unit may be integrated in the control unit 33 of the transmitter module 3 or the processing unit 228 of the sensor unit 22, or may be a module/chip module independent of the aforementioned control unit 33 or processing unit 228.

For example, the pairing information storage unit may store at least one first identity information, and a white list of each first identity information, the white list recording one or more second identity information of the first identity information pairing.

The white list may have historically been based on user settings, such as after the B1 sensor unit 22 is connected to the B2 transmitter module 3, the user may send a lock command to the control unit 33 of the B2 transmitter module 3 to indicate that the two modules are locked. In response to receiving the lock instruction, the control unit 33 acquires the first identification information of itself and the second identification information of the currently connected B1 sensor unit 22 and stores them in a matching manner to the pairing information storage unit.

Thus, on the premise that the gas detection device 1 is modularized into a plurality of independent modules and can be replaced respectively, the present embodiment can lock the sensor unit 22 and the transmitter module 3 together in pairs, avoiding the user from mistakenly replacing an inappropriate component onto the gas detection device 1 to cause component damage. Further, if a user assembles the unpaired sensor unit 22 and transmitter module 3 together, the gas detection apparatus 1 cannot be used normally.

In a typical application scenario, the steps shown in fig. 3 are performed after the sensor module 2 and the transmitter module 3 are assembled, so as to detect whether the currently connected sensor unit 22 and the transmitter module 3 are paired.

Specifically, in response to detecting that there is currently one sensor unit 22 electrically connected to the transmitter module 3, the identity matching unit disposed in the transmitter module 3 may execute step S301 to obtain the first identity information of the transmitter module itself and obtain the second identity information of the sensor unit 22 through the electrical connection.

Next, the pairing information storage unit is searched to determine whether the currently acquired first identity information and the second identity information are paired. For example, a white list corresponding to the first identity information stored in the pairing information storage unit may be searched, and if the currently acquired second identity information is on the white list, the two identity information are paired.

Next, corresponding to step S302, if it is confirmed that the currently connected sensor unit 22 and transmitter module 3 are paired, the connection control unit controls the connection state of the currently connected sensor unit 22 and transmitter module 3 to be a connection success state. At this time, the gas detection device 1 can be used normally, that is, the sensor unit 22 can perform normal gas detection operation under the control of the transmitter module 3.

However, if it is determined that the currently connected sensor unit 22 and transmitter module 3 are not paired, that is, the pairing result of the identity pairing unit is pairing failure, the connection control unit controls the connection state of the currently connected sensor unit 22 and transmitter module 3 to be switched to the connection failure state. At this time, the gas detection device 1 is not used, that is, the function of the sensor unit 22 is disabled.

Further, if the pairing result of the identity pairing unit is that the pairing is failed, the connection control unit may also send a warning message to prompt that an unpaired sensor unit 22 is connected to the transmitter module 3.

Further, the action of step S301 may be performed after each power-up of transmitter module 3. Alternatively, step S301 may be performed upon detection of occurrence of sensor module 2 being connected to transmitter module 3.

In a variation, the pairing information storage unit may be stored outside the gas detection apparatus 1, such as in a cloud, and the identity pairing unit may communicate with the cloud to obtain data stored in the pairing information storage unit. For example, the identity pairing unit may communicate with the cloud over Wi-Fi.

In a variant, the locking function corresponding to the locking control method shown in fig. 3 can be selected by the user as to whether it is enabled, that is to say whether the user can select whether the transmitter module 3 is locked in pair with the sensor unit 22.

Specifically, before step S301, the method may include the steps of: it is detected whether the lock function is enabled (enable).

If the lock function is enabled, the scheme of the embodiment shown in FIG. 3 described above is performed.

If the locking function is disabled, sensor unit 22 and transmitter module 3 can be assembled arbitrarily. That is, any one of the sensor units 22 can be electrically connected to the transmitter module 3, and can perform corresponding signal transmission with the transmitter module 3, and the like.

Further, the user can enable or disable the lockout function through a display unit 32 (shown in FIG. 2) of transmitter module 3, which display unit 32 can include a user interface. Or the locking function can be enabled or disabled remotely in a Wi-Fi mode, a Bluetooth mode and the like through a smart terminal such as a mobile phone.

Thereby, it is possible to control whether or not the transmitter module 3 and the sensor unit 22 are locked in pair, which is advantageous to flexibly cope with diversified demands of users.

In a variation, the steps shown in fig. 3 may be performed by the sensor unit 22, and accordingly, the white list may record one or more first identity information paired with the second identity information in the present variation.

Specifically, if the determination result in step S301 is that the matching is successful, the sensor unit 22 switches to a connection successful state and performs normal operation according to the control signal of the transmitter module 3.

If the determination result in step S301 is that the matching fails, the sensor unit 22 switches to the connection failure state and refuses to perform normal operation. At this time, the transmitter module 3 that failed the pairing can be updated to the white list of the sensor unit 22 according to the indication so that the currently connected sensor unit 22 and transmitter module 3 can be switched to the connection success state. Wherein the indication may be issued by a user.

In one implementation, referring to fig. 2 and 4, the sensor unit 22 may include: a sensor 221 for detecting the VOC concentration of the gas to be detected and generating detection data; a processing unit 228 in communication with the sensor 221, the processing unit 228 receiving the detection data and processing to generate the detection result.

Specifically, the processing unit 228 may be a processor, such as a single chip, disposed in the sensor unit 22.

Further, the detection data may be a voltage signal representing a concentration value of VOC in the gas to be detected, the processing unit 228 converts the voltage signal into a digital serial signal and outputs the digital serial signal, and the output result is a detection result. After obtaining the voltage signal, the processing unit 228 may perform temperature and humidity compensation on the voltage signal, and then convert the voltage signal into a detection result.

Further, the processing unit 228 may also store the main calibration and setting parameters of the sensor 221. For example, the processing unit 228 may perform zero point compensation and/or sensitivity compensation on the detection data (analog signals) sent by the sensor 221 according to a preset calibration curve, and convert the compensated detection data into digital serial signals (digital signals) to obtain the detection result.

The abscissa of the preset calibration curve is VOC concentration, the ordinate is humidity, and different temperatures correspond to different preset calibration curves. The preset calibration curve may be used to represent the sensitivity and zero point of the sensor 221.

The sensitivity refers to the detection accuracy of the sensor 221 at a certain point in the measurement range, and if the measurement range of the sensor 221 for detecting the VOC concentration is 0-100 ppm (parts per million, abbreviated as ppm), the sensitivity refers to the numerical fluctuation degree of multiple measurements within a period of time of detection data of, for example, 50ppm in the middle of the measurement range of the sensor 221. The better the sensitivity is corresponding to a preset calibration curve, the closer the curve approaches to a straight line; the worse the sensitivity, the more the curve fluctuates, and if the deviation of the currently received detection data from the corresponding curve exceeds the preset tolerance range, the processing unit 228 determines that the sensitivity compensation needs to be performed on the detection data.

The zero point refers to detection data when the sensor 221 measures a gas (e.g., air) having no VOC concentration. The VOC concentration of the curve at zero should be zero corresponding to the preset calibration curve, and if the detection data obtained by detecting the VOC concentration of the clean gas (such as air) by the sensor 221 deviates from zero, the processing unit 228 determines that zero compensation is required.

Further, the preset calibration curve may be obtained by drawing detection data obtained by historical detection by the sensor 221 and current temperature and humidity data. For example, the processing unit 228 may collect the detection data acquired by the sensor 221 over a period of time, and store the collected detection data in association with the temperature and humidity data at the time of acquiring each detection data. By analyzing the stored data, preset calibration curves corresponding to different temperatures can be drawn.

Further, since the sensitivity and/or the zero point of the detection data are affected by the temperature and the humidity, the processing unit 228 can determine whether to perform the temperature and humidity compensation operation according to the ambient temperature by analyzing the stored data. For example, when the temperature of the gas to be measured flowing to the sensor 221 falls within a certain range, the processing unit 228 determines that the temperature and humidity compensation operation needs to be performed.

In one implementation, with continued reference to fig. 4, the sensor unit 22 may further include a signal adjusting unit (also referred to as a conditioning board) 229, which is detachably disposed in the sensor unit 22 and is respectively in communication with the sensor 221 and the processing unit 228, wherein the signal adjusting unit 229 is configured to amplify the detection data generated by the sensor 221 and transmit the amplified detection data to the processing unit 228.

Specifically, in the z direction, the signal adjustment unit 229 is detachably disposed between the sensor 221 and the processing unit 228.

Further, the amplification of the signal conditioning unit 229 may be correlated to the range of the sensor 221. However, the smaller the measurement range of the sensor 221 is, the larger the amplification factor of the signal adjustment unit 229 is. When assembling the sensor unit 22, the signal adjustment unit 229 having a corresponding amplification factor can be selected and assembled according to the measurement range of the sensor 221 currently mounted.

In one variation, the signal conditioning unit 229 may select a corresponding amplification from a library of preset amplifications based on the range of the currently coupled sensor 221 and amplify the detection data generated by the sensor 221 using the selected amplification.

Specifically, the signal adjusting unit 229 may store a preset magnification library, which may record the corresponding relationship between the measurement ranges and the magnifications of the plurality of sensors 221. After assembly, the signal conditioning unit 229 may determine the corresponding magnification from a library of preset magnifications based on the actual range of the currently connected sensor 221.

This improves the compatibility of the signal adjustment unit 229.

In one implementation, with continued reference to fig. 4, the sensor unit 22 may further include a temperature compensation unit 222 for controlling the temperature of the gas to be measured flowing through the sensor 221 within a preset temperature range.

Specifically, the temperature compensation unit 222 may include: a temperature measuring unit 223 (shown in fig. 11), wherein the temperature measuring unit 223 is in communication with the processing unit 228, and is configured to detect the temperature of the gas to be measured flowing through the sensor 221 and send a temperature measuring result to the processing unit 228; and a temperature adjustment unit 224 disposed around the sensor 221, wherein the temperature adjustment unit 224 is in communication with the processing unit 228 to receive a temperature adjustment instruction of the processing unit 228, and performs a temperature adjustment operation according to the temperature adjustment instruction, and the temperature adjustment instruction is generated when the temperature measurement result exceeds a preset temperature range.

Fig. 5 is a flow chart of a temperature compensation method for a gas detection device according to an embodiment of the present invention. The method illustrated in fig. 5 may be performed by the processing unit 228.

Specifically, referring to fig. 5, the temperature compensation method for the gas detection apparatus according to the present embodiment may include the following steps:

step S501, obtaining a temperature measurement result, wherein the temperature measurement result is the temperature of the gas to be measured flowing through the sensor 221;

step S502, judging whether the temperature measurement result exceeds a preset temperature range;

in step S503, when the determination result indicates that the temperature measurement result exceeds the preset temperature range, a temperature adjustment instruction is issued, where the temperature adjustment instruction is used to instruct the temperature adjustment unit 224 to perform a temperature adjustment operation.

When the determination result in the step S502 is negative, that is, the temperature measurement result does not exceed the preset temperature range, the step S501 may be executed again until the determination result in the step S502 is positive.

Further, the temperature measurement result in step S501 may be obtained from the temperature measurement unit 223.

Further, the temperature adjustment instructions may be sent to the temperature adjustment unit 224.

Thus, by adding the temperature compensation means 222 to the sensor module 2, condensation on the sensor 221 can be prevented in advance, and the influence of humidity on the detection result of the sensor 221 can be eliminated.

In one implementation, the predetermined temperature range may be a local interval within the limit temperature range that the sensor 221 can withstand. For example, the predetermined temperature range may be a room temperature range, such as 10-40 degrees Celsius (C.). Thus, the temperature of the intake air is maintained near the room temperature range by the temperature compensation unit 222, so that the preset calibration curve corresponding to a temperature outside the room temperature range is hardly recalled during the gas detection performed by the sensor 221. Therefore, the processing unit 228 can only store the preset calibration curve corresponding to the room temperature range, and does not need to store the calibration data of the full range of the sensor 221, thereby effectively reducing the data storage burden of the processing unit 228.

In one implementation, the temperature measurement unit 223 may be disposed near an inlet that delivers the gas to be measured to the sensor 221.

For example, the temperature measurement unit 223 may be a temperature and humidity flexible circuit board, and may be disposed as close as possible to a position where the gas to be measured initially contacts the sensor 221. Such as may be located near the sensing port where the sensor 221 is exposed to the gas cell 235, as shown in fig. 11.

In one implementation, temperature adjustment unit 224 is disposed around sensor 221 to substantially adjust the temperature of the environment surrounding sensor 221, ensuring that the temperature of the gas to be measured has been adjusted to a room temperature range when the gas to be measured flows to sensor 221.

Specifically, in conjunction with fig. 4, 9 and 11, the sensor unit 22 may include a housing 225, the housing 225 having a chamber 226 for accommodating the sensor 221, and the temperature adjustment unit 224 may be attached to a sidewall of the chamber 226 and extend along a circumferential direction of the chamber 226. Accordingly, the temperature adjusting unit 224 adjusts the temperature in the chamber 226 according to the temperature adjusting instruction, and the temperature in the chamber 226 ultimately acts on the temperature of the sensor 221 and the surrounding environment, thereby changing the temperature of the gas to be measured flowing to the sensor 221.

For example, the temperature adjustment unit 224 may have a long bar structure, is attached to the sidewall of the chamber 226 facing the sensor 221, and forms a closed structure around the circumference of the chamber 226.

For another example, the number of temperature adjustment units 224 may be multiple and distributed in multiple orientations of the sensor 221. There may be a space between adjacent temperature conditioning units 224 to allow for cost and even heating.

In one implementation, the height of the temperature adjustment unit 224 in the z-direction may be equal to the height of the chamber 226 in the z-direction. That is, the temperature-adjusting unit 224 may cover substantially the entire sidewall of the chamber 226.

In one variation, the height of the temperature adjustment unit 224 extending along the z-direction may be substantially equal to the height of the sensor 221 along the z-direction, i.e., the temperature adjustment unit 224 may be attached to the sidewall of the chamber 226 only around the space where the sensor 221 is located, as shown in fig. 9. Thus, the temperature of the gas to be measured can be precisely adjusted while saving costs to ensure that the temperature of the gas to be measured flowing to the sensor 221 is within the preset temperature range.

For example, referring to fig. 9, the temperature adjustment unit 224 may surround only the sidewall of the chamber 226 between the signal adjustment unit 229 and the sensor 221 to more accurately adjust the temperature of the gas to be measured in the gas chamber 235.

In one implementation, the temperature adjustment unit 224 may be made of graphene material. For example, the temperature adjustment unit 224 may be a graphene heating sheet.

In one implementation, the temperature adjustment command may be used to indicate the temperature of the heating sensor 221 and its surrounding environment, and accordingly, the temperature adjustment unit 224 may be a heating unit to remove moisture from the gas to be measured. In step S502, the processing unit 228 may determine whether the currently received temperature measurement data is close to or lower than the lower limit of the preset temperature range.

During execution of the temperature adjustment instruction by the temperature adjustment unit 224, the temperature measurement unit 223 may continue to detect the temperature of the gas to be measured flowing to the sensor 221. If the temperature measurement result is close to or greater than the upper limit of the preset temperature range, the processing unit 228 sends a temperature adjustment stop command. In response to receiving the stop temperature adjustment instruction, the temperature adjustment unit 224 stops heating the sensor 221 and its ambient temperature.

In a variation, the judgment in step S502 may be whether the variation trend of the temperature of the gas to be measured in a period of time is beyond a preset temperature range. Therefore, the effect of early intervention can be better realized.

In a variant, the solution of the embodiment shown in fig. 5 can be performed by the control unit 33 in the transmitter module 3. For example, the temperature measuring unit 223 may send the temperature measurement result to the control unit 33 through the data line, and receive the temperature adjustment instruction and the temperature stop instruction sent by the control unit 33 through the control line.

In one implementation, with continued reference to fig. 2, the sensor unit 22 may include a sensor end cap 262 for receiving the aviation plug 263 and enclosing the sensor 221, the temperature compensation unit 222, and the processing unit 228 within the chamber 226. After the sensor 221, the temperature compensation unit 222, and the processing unit 228 are assembled into the chamber 226, the sensor end cap 262 with the aviation plug 263 installed is screwed to the housing 225, completing the assembly of the sensor unit 22.

In one implementation, referring to fig. 1, 2 and 6, transmitter module 3 may include: a display unit 32 for displaying the detection result; a control unit 33 in communication with the display unit 32 and the sensor unit 22, the control unit 33 being configured to receive the detection result and send the detection result to the display unit 32; a terminal unit 34 coupled to the control unit 33, wherein the control unit 33 transmits the detection result to the outside through the terminal unit 34; the display unit 32, the control unit 33, and the terminal unit 34 are arranged in parallel along a first direction (indicated by y-direction in fig. 2), and the first direction (illustrated by y-direction) is perpendicular to a plane of the display unit 32.

The y-direction may be perpendicular to the z-direction to reduce the size of the gas detection apparatus 1 in height.

Specifically, the user can view the real-time detection result of the sensor 221 through the display unit 32. The operating state, operating mode, etc. of the gas detection apparatus 1 may also be controlled by a user interaction interface provided by the display unit 32. The display unit 32 may be formed of a display panel (display board)321 having a user interactive interface. For example, the display panel 321 may be a display screen. For another example, the display panel 321 may have a touch function so as to receive an operation instruction of a user.

Further, the display unit 32 may also be provided with one or more control buttons (not shown) for a user to adjust the operational state of the transmitter module 3 and/or the sensor module 2.

Further, the display unit 32 may also be provided with indicator lights (not shown) to show the operating status of the transmitter module 3 and/or the sensor module 2 to a user. For example, the indicator lights may include a fault indicator light and a normal operation indicator light.

Further, the control unit 33 may be integrated with a storage unit for storing the detection result transmitted from the sensor unit 22. The control unit 33 may be formed of a main board (main board).

Further, the terminal unit 34 may integrate a plurality of terminals, and different terminals correspond to different data transmission types. The terminal unit 34 may be formed of a terminal board (terminal board).

From this, display panel, mainboard and terminal block arrange in proper order along the y direction, have line connection in order to realize signal transmission each other, because the interval between the adjacent circuit board can be equal to the height of device on the circuit board of lower floor basically to can realize compact design, realize demonstration and diversified data transmission function in finite space. Based on such a design, the transmitter module 3 is small in size, so that the gas detection apparatus 1 can be disposed in a narrow space.

In one implementation, with continued reference to fig. 2, the terminal unit 34 may include a plurality of terminals for connecting different serial bus communication modes, so that the terminal unit 34 may be compatible with multiple serial bus communication modes, and a user may select a desired mode for data transmission. It should be noted that fig. 2 only shows the arrangement position and number of the plurality of terminals on the terminal unit 34 by way of example, and in practical applications, the specific type and layout of each terminal on the terminal unit 34 may be adjusted as needed.

Specifically, the terminal unit 34 may include a first terminal 341 and a second terminal 342. The transmitter module 3 may include a communication module 35 arranged in parallel with the display unit 32, the control unit 33, and the terminal unit 34 in the first direction (y direction).

Further, the communication module 35 may be a first communication unit coupled to the first terminal 341, or the communication module 35 may be a second communication unit coupled to the second terminal 342, where the first communication unit and the second communication unit use different serial bus communication methods.

For example, the first communication unit may use a Highway Addressable Remote Transducer (HART) open communication protocol (Highway Addressable Remote Transducer), and the second communication unit may use a ModBus protocol for serial bus communication.

When the transmitter module 3 is assembled, an appropriate communication module 35 can be selected and fixed in the body 36 of the transmitter module 3 according to the serial bus communication mode indicated by the user, and coupled to the corresponding terminal. For example, if the user indicates that the serial bus communication is required by using HART, the circuit boards arranged in the y direction in the body 36 from bottom to top are the first communication unit, the terminal unit 34, the control unit 33 and the display unit 32, and the first communication unit is coupled to the first terminal 341. Moreover, during the use of the gas detection apparatus 1, the second terminal 342 is always in an idle state (i.e. not coupled to the communication module 35), and the detection result is not transmitted through the second terminal 342.

Further, the communication module 35 may be located below the terminal unit 34 in the first direction (y direction). That is, in the y direction, the body 36 is provided therein with the communication module 35, the terminal unit 34, the control unit 33, and the display unit 32 in this order. Further, referring to fig. 2 and 6, the communication module 35 may be independently installed in the body 36, and the terminal unit 34, the control unit 33, and the display unit 32 are sequentially installed in the support part 362 to form an assembly and then are collectively installed in the body 36. Therefore, when replacing the communication module 35, only the support part 362 needs to be removed quickly, and the normal operation of other components in the transmitter module 3 is not affected.

Further, with continued reference to fig. 6, the communication module 35 and the terminal unit 34 may have a cable passing portion 37 therebetween. A cable (not shown) enters the body 36 through the cable passing portion 37 and is connected to the power supply port and the signal port of the terminal unit 34. The communication module 35 is connected to the corresponding terminal of the terminal unit 34 to transmit the detection result through the terminal to the outside via the cable.

Further, the cable may be fixed to the cable passing portion 37 by the cable fixing portion 371.

In a variation, the communication module 35 may be omitted, i.e., the body 36 may not have the communication module 35 disposed therein. At this time, the control unit 33 may realize transmission of the detection result through another terminal (a third terminal 343 described below) on the terminal unit 34.

In one implementation, with continued reference to fig. 2, the terminal unit 34 may include a third terminal 343, and the control unit 33 may bulk-transmit the detection results received within a period of time and/or receive external data through the third terminal 343.

For example, the number of the third terminals 343 may be two, wherein one of the third terminals 343 may be used to export the detection results stored in the storage unit of the control unit 33 in batches and receive an upgrade patch to update the software of the control unit 33; wherein another third terminal 343 may be used to receive upgrade patches to upgrade the overall system of the gas detection apparatus 1.

Further, the third terminal 343 may be a USB interface.

Thus, the terminal unit 34 may be provided with a first terminal 341 and a second terminal 342, which may allow real-time transmission of the detection results, and a third terminal 343, which may allow batch, asynchronous transmission of the detection results. The data transmission form of the transmitter module 3 is richer, and the diversified requirements of users can be met.

In one implementation, with continued reference to fig. 2, the terminal unit 34 may further include a fourth terminal 344, the fourth terminal 344 is coupled to an external alarm device (not shown), and the control unit 33 controls the external alarm device to operate through the fourth terminal 344.

For example, the external alarm device may comprise an audible and visual alarm. The control unit 33 may analyze the received detection result, and if the detection result indicates that the VOC concentration in the current environment to be detected exceeds the warning standard, the control unit 33 sends an alarm command through the fourth terminal 344 to control the audible and visual alarm to alarm.

In one implementation, the transmitter module 3 may further include a wireless communication unit (not shown) in communication with the control unit 33, and the control unit 33 transmits the detection result and/or receives external data in a wireless manner through the wireless communication unit.

For example, the wireless communication unit may be integrated with the display unit 32 to avoid the metal housing adopted by the body 36 from adversely affecting the wireless transmission signal.

Further, the wireless communication unit may be a Wi-Fi communication unit. Alternatively, the wireless communication unit may be a bluetooth communication unit.

Further, the control unit 33 may also receive a control instruction of the user through the wireless communication unit. Further, the upgrade patch may be received through the wireless communication unit to update the software of the control unit 33.

In one implementation, with continued reference to fig. 2 and 6, transmitter module 3 may include a cover 361 that covers the periphery of body 36 to protect the various circuit boards and other devices mounted within body 36. The upper cover 361 may be opened with an opening exposing the display unit 32.

In one implementation, referring to fig. 2, 4, 7 and 8, the pump assembly 23 can include a snap-fit portion 231 and the sensor unit 22 can include an adapter portion 227, the snap-fit portion 231 cooperating with the adapter portion 227 to removably mechanically couple the pump assembly 23 and the sensor unit 22.

For example, the snap-in portion 231 may be a hook portion, and the fitting portion 227 may be a recess recessed into the cavity 226 from the housing 225 of the sensor unit 22. When assembled, the hook portion hooks over the recess to effect fixation of the pump assembly 23 and the sensor unit 22.

Thereby, the pump assembly 23 and the sensor unit 22 also form a modular structure, and either module can be replaced individually.

In one implementation, with continued reference to fig. 2, 7, and 8, the pump assembly 23 may include: a pump 232, such as an air pump; the gas collecting member 233 is located between the pump 232 and the sensor unit 22, the gas collecting member 233 may include a main body 234, a gas chamber 235 for accommodating the gas to be measured is provided on a side of the main body 234 facing the sensor unit 22, the sensor 221 of the sensor unit 22 is at least partially exposed to the gas chamber 235, and the gas chamber 235 is communicated with the pump 232.

Specifically, the detection port of the sensor 221 may be disposed opposite to the gas chamber 235 to ensure timely and accurate detection of the VOC concentration of the gas to be detected in the gas chamber 235, as shown in fig. 6 and 11.

Further, the air chamber 235 may be formed by a concave opening formed in the main body portion 235, and the area of the air chamber 235 is large, so that the flow velocity of the gas to be measured can be properly reduced after the gas flows into the air chamber 235. The detection port of the sensor 221 may be located towards the center point of the gas chamber 235, i.e. the projection of the detection port onto the gas collector 233 may be located substantially in the center of the gas chamber 235.

In a typical application scenario, the gas to be measured is sucked into the sensor module 2 via the pump 232, flows into the gas chamber 235, is deposited and stays slightly for the sensor 221 to detect sufficiently, and then is discharged out of the sensor module 2 under the action of the pump 232.

From above, the gas-collecting part 233 arranged between the pump 232 and the sensor 221 can play a role in sufficiently fusing the gas to be detected and prolonging the contact time between the gas to be detected and the sensor unit 22, so as to ensure that the detection port of the sensor 221 sufficiently contacts the gas to be detected, thereby improving the detection precision.

In one implementation, the projection of the temperature measurement unit 223 on the gas collection member 233 may be located within the gas chamber 235, as shown in fig. 11, so as to accurately detect the temperature of the gas to be measured.

In one implementation, with continued reference to FIG. 8, the body portion 234 may define an inlet 236 and an outlet 237, respectively, in communication with the pump 232. The gas to be measured enters the gas chamber 235 from the gas inlet 236 and exits the gas chamber 235 through the gas outlet 237 under the driving of the pump 232.

Further, the air chamber 235 may be located between the air inlet 236 and the air outlet 237. For example, the gas inlet 236, the gas chamber 235 and the gas outlet 237 may be arranged along the same straight line to minimize wind resistance of the gas to be measured flowing from the gas inlet 236 to the gas outlet 237, thereby improving gas flow efficiency.

Further, the area of the gas chamber 235 may be larger than the area of either of the gas inlet 236 and the gas outlet 237, so as to prolong the retention time of the gas to be measured in the gas chamber 235 as much as possible while ensuring the overall high gas flow efficiency, and to take into account the detection accuracy of the sensor 221.

Further, a flow guide groove 238 may be provided between the air inlet 236 and the air chamber 235. Similarly, a flow directing groove 238 may be provided between the air outlet 237 and the air chamber 235. The gas to be measured flows from the gas inlet 236 to the gas chamber 235 along the flow guiding groove 238, and then flows to the gas outlet 237 along the flow guiding groove 238.

Further, the drainage groove 238 may be the shortest connecting path between the gas inlet 236 and the gas chamber 235 to ensure that the gas to be detected can reach the gas chamber 235 as fast as possible to be detected by the sensor 221, thereby improving the response speed of the gas detection device 1.

Further, the flow guide groove 238 may be the shortest connecting path between the air outlet 237 and the air chamber 235 to reduce the wind resistance of the gas flow path.

Further, the drainage groove 238 is wider as it is closer to the gas chamber 235 in the flow direction of the gas to be measured. Wherein the drainage groove 238 is defined by a bottom wall facing the sensor 221 and a pair of side walls, and the width of the drainage groove 238 refers to the distance between the pair of side walls.

In other words, the main body 234 may be opened with a flying saucer-shaped groove 239 on a side facing the sensor unit 22, a disk of the groove 239 forms the air chamber 235, and the wing ends of the groove 239 form the air inlet 236 and the air outlet 237, respectively. Because the middle of the flying saucer-shaped groove 239 is large and the two ends are small, the gas to be measured can flow from the gas inlet 236 to the gas chamber 235 smoothly and quickly, and cannot be discharged from the gas outlet 237 too quickly. Thus, the gas to be measured can be sufficiently stayed in the gas chamber 235, thereby improving the detection accuracy of the sensor 221.

Further, the width of the drainage groove 238 may be smoothly transitioned in the flow direction of the gas to be measured to reduce wind resistance.

In one implementation, with continued reference to fig. 2, 7, and 8, the plenum 233 can further include a wall 234a disposed around an edge of the body portion 234 and extending in a direction of the sensor unit 22, the wall 234a at least partially encasing the housing 225 of the sensor unit 22.

After assembly, the lower half of the sensor unit 22 is embedded in the space enclosed by the wall 234a of the gas collector 233 to ensure effective contact between the sensor 221 and the gas to be measured in the gas chamber 235.

Further, the wall 234a may be provided with a snap portion 231, and the housing 225 of the sensor unit 22 may have an adapting portion 227, and the snap portion 231 may be detachably connected to the adapting portion 227.

Further, the pump assembly 23 may further include a sealing mechanism 247 disposed between the air collector 233 and the sensor unit 22 to isolate at least the air chamber 235 from the outside.

For example, the main body 234 may be formed with an annular groove 234b at its edge, and the sealing mechanism 247 may be a sealing ring. When assembled, the sealing ring is inserted into the annular groove 234b, and then the sensor unit 22 is inserted downward into the space defined by the wall 234a of the air collector 233 in the direction opposite to the z direction until the locking portion 231 is locked to the main fitting portion 227. At this time, the seal ring is pressed and deformed by the sensor unit 22, so that most of the area of the main body 234 is isolated from the outside, and the gas to be measured in the gas chamber 235 is prevented from flowing to the outside.

In one implementation, with continued reference to fig. 8, body portion 234 may include a quick connect end 234c, with pump 232 and transmitter module 3 being coupled through quick connect end 234 c.

For example, the quick connect end 234c may be a metal contact that is hard-wired to a conductive terminal (not shown) of the sensor unit 22 to capture power from the power cord and deliver the power to the pump 232 when the sensor unit 22 and the manifold 233 are assembled in place. Wherein, the hard contact can mean that the metal contact and the conductive terminal are lapped to realize the electric connection. Further, the transmitter module 3 can also transmit a control signal to the pump 232 through the metal contact to control the operation state of the pump 232.

Further, the pump 232 can be fixed to the gas collecting member 233 by screws, and the main body 234 is provided with mounting holes (not shown) adapted to the screws.

Further, the mounting hole may be plural and symmetrical with respect to the center point of the air chamber 235. Similarly, the quick connect end 234c may be plural and symmetrical about the center point of the air chamber 235.

In one implementation, with continued reference to fig. 2, 4, 9, and 11, a foam 261 can be disposed within the chamber 226 of the sensor unit 22 around the sensor 221, the foam 261 opening to expose a detection port of the sensor 221 to isolate the chamber 226 from the gas chamber 235 while ensuring that the detection port contacts the gas chamber 235.

For example, the foam 261 may be EVA foam (also called EVA sponge), which has the effects of shock resistance and gas isolation, and prevents the gas to be measured from diffusing into the entire chamber 226.

After assembly, foam 261 is interference fit with sensor 221 to confine the gas to be measured within gas chamber 235. By restricting the concentration of the gas to be measured in the gas chamber 235 from contacting the detection port of the sensor 221, the concentration of the gas to be measured in the gas chamber 235 can be maintained.

In one implementation, with continued reference to fig. 1, 2, 9-11, fig. 9-11 are cross-sectional views of sensor module 2 taken along different directions and angles. To more clearly show the air passage structure in the sensor module 2, fig. 10 and 11 only show a partial sectional structure of the sensor module 2.

In particular, the sensor module 2 may further comprise a housing 24 for accommodating the sensor unit 22 and the pump assembly 23. The housing 24 has a substantially hollow cylindrical shape and an upper end in the z direction has an opening that exposes the hollow cavity, and after the pump unit 23 and the sensor unit 22 are sequentially placed in the hollow cavity, the cover 25 closes the opening to enclose the pump unit 23 and the sensor unit 22 in the housing 24.

More specifically, the side wall of the casing 24 is provided with an air outlet 241, the bottom of the casing 24 is provided with an air inlet 242, and the air outlet 241 and the air inlet 242 are respectively communicated with the pump assembly 23. Here, the bottom of the case 24 means a lower end in the z direction.

Further, the sensor module 2 may further include a cover portion 25, and after the pump assembly 23 and the sensor unit 22 are assembled in the housing 24, the cover portion 25 closes the opening of the housing 24 to complete the assembly of the sensor module 2.

Further, the number of the air outlet holes 241 may be plural and provided at the side wall at intervals along the circumferential direction of the housing 24. Therefore, the gas discharge efficiency can be improved, and the influence of the gas detection operation of the gas detection device 1 on the concentration of the gas to be detected in the environment to be detected can be reduced.

For example, the plurality of air outlet holes 241 may be uniformly distributed in the sidewall of the housing 24 along the circumference thereof.

Further, the air outlet holes 241 may be disposed adjacent to the air inlet holes 242. That is, the air outlet hole 241 may be provided at a position where the sidewall of the housing 24 is close to the bottom of the housing 24.

Further, the pump assembly 23 may include a gas distribution plate 245, integrating a first intake conduit 243 communicating the intake hole 242 with the pump 232, and a second intake conduit 248 communicating the pump 232 with the sensor 221. For example, one end of the first air intake pipe 243 is connected to the air intake hole 242, and the other end is connected to the air pump inlet 232 a. One end of the second air inlet pipe 248 is connected to the air pump outlet 232b, the other end is connected to the air inlet air duct 246a, and the air inlet air duct 246a is connected to the air inlet 236. So that the gas to be measured enters the sensor module 2 through the inlet hole 242 and flows to the inlet 236 by the pump 232.

Further, the gas distribution plate 245 may further integrate a gas outlet pipe 244 communicating the sensor 221 and the gas outlet hole 241. For example, the gas outlet 237 is connected to the gas outlet tube 246b, and the gas outlet tube 246b is connected to the gas outlet pipe 244, so that the gas to be measured flows from the gas outlet 237 to the gas outlet 241 via the gas outlet tube 246b and the gas outlet pipe 244 in sequence.

Further, a filter device such as a filter screen may be disposed between the first air inlet pipe 243 and the air inlet hole 242 to perform pretreatment such as dust removal before the gas to be detected enters the air chamber 235, so as to ensure better detection accuracy. For example, in the z-direction, a filter device may be disposed between the gas distribution plate 245 and the gas inlet holes 242.

Further, the first air intake pipe 243 may be provided with a waterproof permeable membrane 249 to prevent external moisture from entering to affect the detection accuracy of the sensor 221. Further, the waterproof permeable membrane 249 can also exert a certain degree of dust-proof effect.

Further, the first air inlet conduit 243 and the second air inlet conduit 248 may be collectively referred to as a primary vent conduit that is completely separate from the outlet conduit 244 within the gas distribution plate 245 to avoid interference between the inlet and outlet gases. Similarly, inlet airway 246a and outlet airway 246b are also separate airway tubes to prevent the inlet and outlet air from interfering with each other.

Alternatively, the outlet line 244 may communicate with the pump 232 and the primary vent line communicates directly with the inlet aperture 242 and the inlet 236, again achieving complete separation of the inlet and outlet gases.

Alternatively still, the primary vent line and the outlet line 244 may each communicate with the pump 232. This facilitates the achievement of a rapid flow of the gas to be measured within the sensor module 2.

Further, one end of the air outlet pipe 244 connected to the air outlet 241 may be provided with a waterproof membrane 249, so as to prevent external moisture from entering from the air outlet 241 due to splashing and other factors, and thus, the detection accuracy of the sensor 221 is affected.

Further, along the z-direction, a sintered ring, a sintered sheet and other components can be arranged between the lower end of the sensor module 2 and the gas distribution plate 245, so as to achieve a better explosion-proof effect.

In a variation of the air passage structure shown in fig. 9 to 11, referring to fig. 12, the pump assembly 23 may further include: an auxiliary vent line 264 for directly communicating the gas chamber 235 with the outside of the sensor module 2; an air passage switching mechanism (not shown) for controlling the communication state of the primary vent line and the secondary vent line 264 connecting the pump 232 and the air chamber 235.

Specifically, the air passage switching mechanism may control one of the primary vent passage and the secondary vent passage 264 to be in a connected state while the other is in a disconnected state. That is, by adding the gas path switching mechanism, the operating mode of the gas detection device 1 can be switched between the pumping mode and the diffusion mode.

The pumping type means that the gas to be measured is actively sucked into the sensor module 2 through the pump 232 via the main ventilation pipeline (including the first air inlet pipeline 243 and the second air inlet pipeline 248) and the air inlet air duct 246a in the air path structure shown in fig. 9 to 11.

The diffusion mode is that the main vent line is closed, the pump 232 does not work, but the gas to be measured is obtained from the gas inlet hole 242 through the auxiliary vent line 264, and at this time, the gas to be measured is blown into the gas inlet hole 242 through the external pump (not shown).

Further, the inlet of the auxiliary ventilation line 264 may be connected to an external pump. The inlet of the secondary vent line 264 may multiplex the inlet vents 242. Alternatively, the two may be independent two inlet ends.

Further, the air path switching mechanism may be disposed at the air pump inlet 232a and/or the air pump outlet 232b of the pump 232 to control the on/off of at least one of the air ports.

Further, a secondary vent line 264 may be integrated into the gas distribution plate 245 along with the primary vent line 264, with one end of the secondary vent line 264 being connected to the second inlet line 248 and the other end of the secondary vent line 264 being connected to the inlet holes 242. At this point, the secondary vent line 264 and the second air intake line 248 form a tee. From this, gas circuit switching mechanism can switch the gas circuit between built-in pump 232 and external pump, and when switching over to the external pump of intercommunication, pump 232 and corresponding gas circuit cut off, and air chamber 235 directly links the external pump through the three-way pipe.

Further, the secondary vent line 264 may include: a limit pin 265 and a check ball 266, the check ball 266 being located within the limit pin 265. Check ball 266 is used to prevent backflow of air through inlet holes 242.

In a typical application scenario, in response to the operation mode of the gas detection apparatus 1 being switched from the pumping mode to the expansion mode, the processing unit 33 may control the pump 232 to stop operating, and the air path of the air pump inlet 232 a/the air pump outlet 232b is cut off.

Further, the external pump works, and the gas to be measured enters the auxiliary ventilation pipeline 264 integrated on the gas distribution plate 245 through the air inlet (such as the air inlet 242) of the external pump.

Further, the gas to be measured pushes the check valve ball 266 to rise, and the rising height is limited by the limit pin 265. At this time, the gas to be measured flows into the intake air guide tube 246a through the gap between the check valve ball 266 and the inner wall of the auxiliary ventilation line 264, and further reaches the intake port 236.

Therefore, in the variation, the gas to be detected can be pumped into the sensor module 2 through the external pump without manual replacement of a user, and the method is suitable for the pumping scene of the large-flow external pump.

Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A gas detection apparatus, comprising:

the sensor module comprises a sensor unit for detecting the VOC concentration of the gas to be detected and generating a detection result;

wherein the sensor unit includes:

the sensor is used for detecting the VOC concentration of the gas to be detected and generating detection data;

a processing unit in communication with the sensor, the processing unit receiving the detection data and processing to generate the detection result;

and the temperature compensation unit is used for controlling the temperature of the gas to be measured flowing through the sensor within a preset temperature range.

2. The gas detection apparatus of claim 1, wherein the temperature compensation unit comprises:

the temperature measuring unit is communicated with the processing unit and is used for detecting the temperature of the gas to be measured flowing through the sensor and sending a temperature measuring result to the processing unit;

and the temperature adjusting unit is arranged around the sensor and is communicated with the processing unit so as to receive a temperature adjusting instruction of the processing unit and execute temperature adjusting operation according to the temperature adjusting instruction, and the temperature adjusting instruction is generated when the temperature measuring result exceeds a preset temperature range.

3. The gas detection apparatus of claim 2, wherein the temperature measurement unit is disposed near an inlet port that delivers the gas to be measured to the sensor.

4. The gas detection device according to claim 3, wherein the sensor module further comprises a gas collecting member, a side of the gas collecting member facing the sensor unit is provided with a gas chamber for accommodating the gas to be measured, the sensor is at least partially exposed to the gas chamber, and a projection of the temperature measuring unit on the gas collecting member falls into the gas chamber.

5. The gas detection apparatus of claim 2, wherein the sensor unit includes a housing having a cavity for accommodating the sensor, and the temperature adjustment unit is attached to a sidewall of the cavity and extends in a circumferential direction of the cavity.

6. A gas detection apparatus as claimed in claim 5 wherein the temperature conditioning unit is elongate and forms a closed configuration end to end around the circumference of the chamber.

7. The gas detection apparatus of claim 2, wherein the temperature adjustment unit is plural in number and distributed in plural orientations of the sensor.

8. The gas detection apparatus of claim 2, wherein the temperature adjustment unit is made of graphene material.

9. The gas detection apparatus according to claim 2, wherein a height of the temperature adjustment unit is equal to a height of the sensor in a height direction of the gas detection apparatus.

10. The gas detection apparatus of claim 1, wherein the predetermined temperature range is a local segment within a span temperature range of the sensor.

11. The gas detection apparatus of claim 1, further comprising:

and the transmitter module is detachably connected with the sensor module and is used for receiving the detection result and transmitting the detection result outwards.

12. The gas detection apparatus of claim 1, wherein the sensor module further comprises:

and the pump assembly is detachably connected with the sensor unit, and the gas to be detected is sucked into the sensor module by the pump assembly and is discharged by the pump assembly after flowing through the sensor unit.

13. A temperature compensation method for a gas detection apparatus including a sensor for detecting a VOC concentration of a gas to be detected and generating detection data, the method comprising:

acquiring a temperature measurement result, wherein the temperature measurement result is the temperature of the gas to be measured flowing through the sensor;

judging whether the temperature measurement result exceeds a preset temperature range or not;

and when the judgment result shows that the temperature measurement result exceeds the preset temperature range, adjusting the temperature of the gas to be measured flowing through the sensor.

14. The temperature compensation method of claim 13, wherein the gas detection device includes a temperature adjustment unit disposed around the sensor, the adjusting the temperature of the gas to be measured flowing through the sensor including:

and sending a temperature adjusting instruction, wherein the temperature adjusting instruction is used for instructing the temperature adjusting unit to execute temperature adjusting operation.

15. The method of claim 13, wherein the determining whether the temperature measurement result exceeds a predetermined temperature range comprises:

comparing whether the single temperature measurement result exceeds a preset temperature range or not; and/or

And predicting whether the trend of exceeding the preset temperature range exists according to the change trend of the plurality of temperature measurement results acquired within a period of time.

16. The temperature compensation method of claim 13, further comprising:

continuously acquiring a temperature measurement result during temperature adjustment;

and when the temperature measurement result shows that the temperature of the gas to be measured returns to the preset temperature range, stopping regulating the temperature of the gas to be measured flowing through the sensor.