CN216208882U

CN216208882U - Gas detection device

Info

Publication number: CN216208882U
Application number: CN202121782003.7U
Authority: CN
Inventors: 董汉; 侯斐; 郑宏霏; 秦飞
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: 2022-04-05
Anticipated expiration: 2031-08-02

Abstract

A gas detection apparatus comprising: the sensor module comprises a sensor unit and a pump assembly, wherein the sensor unit is used for detecting the VOC concentration of the gas to be detected and generating a detection result, the pump assembly is detachably connected with the sensor unit, and the gas to be detected enters the sensor module from an air inlet under the action of the pump assembly and is discharged from an air outlet after flowing through the sensor unit; a main vent line communicating the air intake and the sensor unit via the pump assembly; the air outlet pipeline is communicated with the sensor unit and the air outlet; the main ventilation pipeline and the air outlet pipeline are mutually independent and located on the same side of the sensor unit, and the number of the air outlet holes is multiple and surrounds the air inlet holes. The scheme of the utility model can improve the response speed of the gas detection device.

Description

Gas detection device

Technical Field

The utility model relates to the technical field of gas detection, in particular to a gas detection device.

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 detects toxic and harmful gas by detecting the VOC concentration of the inhaled gas to be detected, and the detected gas to be detected is discharged out of the gas detection device. However, the gas path design in the existing gas detection device has many unreasonables, which affect the response speed of the gas detection device.

Disclosure of Invention

The utility model solves the technical problem of providing an improved gas detection device.

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 and a pump assembly, wherein the sensor unit is used for detecting the VOC concentration of the gas to be detected and generating a detection result, the pump assembly is detachably connected with the sensor unit, and the gas to be detected enters the sensor module from an air inlet under the action of the pump assembly and is discharged from an air outlet after flowing through the sensor unit; a main vent line communicating the air intake and the sensor unit via the pump assembly; the air outlet pipeline is communicated with the sensor unit and the air outlet; the main ventilation pipeline and the air outlet pipeline are mutually independent and located on the same side of the sensor unit, and the number of the air outlet holes is multiple and surrounds the air inlet holes.

Optionally, the sensor module further includes: the casing is used for containing the sensor unit and the pump assembly, the air outlet is formed in the side wall of the casing, and the air inlet is formed in the bottom of the casing.

Optionally, the plurality of air outlets are arranged on the side wall of the shell at intervals along the circumferential direction of the shell.

Optionally, the air outlet is disposed adjacent to the air inlet.

Optionally, the pump assembly comprises a pump, and the primary vent line comprises a first inlet line communicating the inlet aperture with the pump, and a second inlet line communicating the pump with the sensor unit.

Optionally, the main ventilation pipeline and the air outlet pipeline are independently integrated in the air distribution plate.

Optionally, the gas detection apparatus further comprises: an auxiliary ventilation pipeline for directly communicating the sensor unit with the outside; and the air path switching mechanism is used for controlling the conduction state of the main ventilation pipeline and the auxiliary ventilation pipeline.

Optionally, the air passage switching mechanism controls one of the main ventilation pipeline and the auxiliary ventilation pipeline to be in a connected state, and the other of the main ventilation pipeline and the auxiliary ventilation pipeline is in a disconnected state.

Optionally, an air inlet of the auxiliary ventilation pipeline is connected with an external pump, wherein the air inlet is multiplexed with the air inlet hole or is independent of the air inlet hole.

Optionally, the main ventilation pipeline includes a first air inlet pipeline communicating the air inlet hole and the pump, and a second air inlet pipeline communicating the pump and the sensor unit, one end of the auxiliary ventilation pipeline is connected to the second air inlet pipeline, and the other end of the auxiliary ventilation pipeline is connected to the air inlet hole.

Optionally, the main ventilation pipeline, the auxiliary ventilation pipeline and the air outlet pipeline are independently integrated in an air dividing plate.

Optionally, the pump assembly includes a pump, and the air path switching mechanism is disposed at an air pump air inlet and/or an air pump air outlet of the pump.

Optionally, the secondary vent line comprises: the check valve ball is positioned in the limiting pin.

Optionally, the main vent line and/or the outlet line is provided with a water-proof permeable membrane.

Optionally, 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.

Optionally, the pump assembly comprises: the pump is used for controlling the gas to be measured to flow in the sensor module; the gas collecting piece is positioned between the pump and the sensor unit and comprises a main body part, one side, facing the sensor unit, of the main body part is provided with a gas chamber used for containing the gas to be detected, at least part of a sensor of the sensor unit is exposed in the gas chamber, and the gas chamber is communicated with the pump.

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.

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

an embodiment of the present invention provides a gas detection apparatus, including: the sensor module comprises a sensor unit and a pump assembly, wherein the sensor unit is used for detecting the VOC concentration of the gas to be detected and generating a detection result, the pump assembly is detachably connected with the sensor unit, and the gas to be detected enters the sensor module from an air inlet under the action of the pump assembly and is discharged from an air outlet after flowing through the sensor unit; a main vent line communicating the air intake and the sensor unit via the pump assembly; the air outlet pipeline is communicated with the sensor unit and the air outlet; the main ventilation pipeline and the air outlet pipeline are mutually independent and located on the same side of the sensor unit, and the number of the air outlet holes is multiple and surrounds the air inlet holes.

This embodiment can improve gas detection device's response speed. Particularly, the gas inlet branch and the gas outlet branch are independent from each other, and discharged gas cannot influence the concentration of sucked gas, so that the detection precision of the gas detection device is improved. Furthermore, the air inlet branch and the air outlet branch which are positioned on the same side of the sensor can shorten the length of an air path inside the device, and the improvement of the response speed is facilitated. Further, the design of a plurality of ventholes makes the gas that awaits measuring can be discharged rapidly, improves gaseous exhaust efficiency. Therefore, the response speed of the gas detection device is improved by improving the gas flow efficiency in the whole gas path structure formed by the gas inlet hole, the main vent pipeline, the gas outlet pipeline and the gas outlet hole.

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 sensor module of FIG. 1;

FIG. 3 is an exploded view of the sensor unit of FIG. 2;

FIG. 4 is an exploded view of the pump assembly of FIG. 2;

FIG. 5 is a schematic view of the air-collecting member of FIG. 4;

FIGS. 6-8 are schematic diagrams of the air path structure in the sensor module of FIG. 1;

FIG. 9 is a schematic view of a variation of the air passage structure shown in FIGS. 6-8;

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; z-the height direction of the gas detection device.

Detailed Description

As background art shows, there are many unreasonables in the design of the gas path in the existing gas detection device, which affect the response speed of the gas detection device. For example, in some existing gas detection devices, gas suction and gas discharge are realized through the same path, and the concentration of the sucked gas may be affected by the discharged gas, which may result in inaccurate detection. For another example, although some existing gas detection devices separately design the gas inlet pipeline and the gas outlet pipeline, the gas inlet channel and the gas outlet channel are disposed on different sides of the sensor, and the gas to be detected needs to reach the sensor through a long section of path and then be discharged through a long section of path, so that the response speed of detection is reduced.

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 sensor module of 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. 3). 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, referring to fig. 2 and 3, 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. 3, 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. 3, 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. 8), 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.

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. 8.

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. 3, 6 and 8, 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 its 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. 6, 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 lower limit of the preset temperature range, the processing unit 228 sends a temperature adjustment stopping 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 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 cover 262 with the aviation plug 263 mounted thereon is screwed to the housing 225, completing the assembly of the sensor unit 22.

In one implementation, referring to fig. 2-5, 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. 2-5, 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 8.

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. 8, so as to accurately detect the temperature of the gas to be measured.

In one implementation, with continued reference to FIG. 5, 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 surrounded 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, 4, and 5, the gas-collecting member 233 may further include a wall 234a disposed around a rim 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. 5, 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, 3, 6, and 8, 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, 6-8, fig. 6-8 are cross-sectional views of sensor module 2 taken along different directions and angles. To more clearly show the air path structure in the sensor module 2, fig. 7 and 8 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, a main vent line 244 may be provided in the sensor module 2, wherein the main vent line communicates with the air inlet hole 242 and the sensor unit 22 (e.g., the air inlet 236) via the pump assembly 23, and an outlet line 244 communicates with the sensor unit 22 (e.g., the air outlet 237) and the air outlet hole 241. Further, the main vent line and the outlet line 244 are independent of each other and are located on the same side of the sensor unit 22 in the z-direction.

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. 6 to 8, referring to fig. 9, 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. 6 to 8.

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 utility model as defined in the appended claims.

Claims

1. A gas detection apparatus, comprising:

the sensor module comprises a sensor unit and a pump assembly, wherein the sensor unit is used for detecting the VOC concentration of the gas to be detected and generating a detection result, the pump assembly is detachably connected with the sensor unit, and the gas to be detected enters the sensor module from an air inlet under the action of the pump assembly and is discharged from an air outlet after flowing through the sensor unit;

a main vent line communicating the air intake and the sensor unit via the pump assembly;

the air outlet pipeline is communicated with the sensor unit and the air outlet;

the main ventilation pipeline and the air outlet pipeline are mutually independent and located on the same side of the sensor unit, and the number of the air outlet holes is multiple and surrounds the air inlet holes.

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

the casing is used for containing the sensor unit and the pump assembly, the air outlet is formed in the side wall of the casing, and the air inlet is formed in the bottom of the casing.

3. The gas detection apparatus of claim 2, wherein the plurality of gas outlet holes are provided at intervals in a circumferential direction of the housing at a side wall of the housing.

4. The gas detection apparatus of claim 1, wherein the gas outlet hole is disposed adjacent to the gas inlet hole.

5. The gas detection apparatus of claim 1, wherein the pump assembly includes a pump, and the primary vent line includes a first inlet line communicating the inlet aperture and the pump, and a second inlet line communicating the pump and the sensor unit.

6. The gas detection apparatus of claim 1, wherein the primary vent line and the outlet line are independently integrated into a gas panel.

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

an auxiliary ventilation pipeline for directly communicating the sensor unit with the outside;

and the air path switching mechanism is used for controlling the conduction state of the main ventilation pipeline and the auxiliary ventilation pipeline.

8. The gas detection device of claim 7, wherein the gas path switching mechanism controls one of the primary vent line and the secondary vent line to be in a connected state while the other is in a disconnected state.

9. The gas detection device of claim 7, wherein an external pump is connected to an inlet of the secondary vent line, wherein the inlet is multiplexed with or independent of the inlet.

10. The gas detection apparatus of claim 7, wherein the primary vent line comprises a first inlet line communicating the inlet hole and a pump, and a second inlet line communicating the pump and a sensor unit, wherein one end of the secondary vent line is connected to the second inlet line, and wherein the other end of the secondary vent line is connected to the inlet hole.

11. The gas detection apparatus of claim 7, wherein the primary vent line, the secondary vent line, and the outlet line are independently integrated within a gas distribution plate.

12. The gas detection apparatus of claim 7, wherein the pump assembly comprises a pump, and the air path switching mechanism is disposed at an air pump inlet and/or an air pump outlet of the pump.

13. The gas detection apparatus of claim 7, wherein the secondary vent line comprises: the check valve ball is positioned in the limiting pin.

14. The gas detection apparatus of claim 1, wherein the primary vent line and/or the outlet line is provided with a water-impermeable membrane.

15. The gas detection apparatus of claim 1, wherein the sensor unit comprises: 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.

16. The gas detection apparatus of claim 1, wherein the pump assembly comprises:

the pump is used for controlling the gas to be measured to flow in the sensor module;

the gas collecting piece is positioned between the pump and the sensor unit and comprises a main body part, one side, facing the sensor unit, of the main body part is provided with a gas chamber used for containing the gas to be detected, at least part of a sensor of the sensor unit is exposed in the gas chamber, and the gas chamber is communicated with the pump.

17. 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.