CN113932863A

CN113932863A - Gas measuring apparatus

Info

Publication number: CN113932863A
Application number: CN202111344395.3A
Authority: CN
Inventors: 周昌全; 冯勇; 黄立基
Original assignee: Siargo Ltd
Current assignee: Siargo Ltd
Priority date: 2021-11-15
Filing date: 2021-11-15
Publication date: 2022-01-14

Abstract

The invention relates to the technical field of gas measuring equipment, in particular to a gas measuring device. The gas measuring device comprises a sensing chip, a closed pipeline and an impurity collector and disperser; the two ends of the closed pipeline are respectively provided with a gas inlet and a gas outlet, and the impurity collector and the sensing chip are both arranged in the closed pipeline and are sequentially arranged along the direction of gas flow; the impurity collector and diffuser is provided with a plurality of blades, the blades are sequentially arranged along the circumferential direction around the central axis of the closed pipeline, the blades are provided with turnover parts, and the included angles between the turnover parts and the radial cross section of the closed pipeline are acute angles. The gas measuring device provided by the invention can measure the gas with low cleanliness and has a wide application range.

Description

Gas measuring apparatus

Technical Field

The invention relates to the technical field of gas measuring equipment, in particular to a gas measuring device.

Background

Since the eighties of the twentieth century, the thermal flow sensing chip of the micro-electromechanical system is beginning to be used for measuring gas and fluid, and is currently widely applied to medical equipment, automobile combustion efficiency and other aspects.

However, the thermal flow sensing chip of the mems has a high requirement for cleanliness of the gas to be measured, and if the cleanliness of the gas to be measured is poor, the thermal flow sensing chip of the mems is easily damaged by collision of impurities in the gas, so that the conventional gas measuring apparatus using the thermal flow sensing chip of the mems has a limited application range and is difficult to measure the gas with low cleanliness.

In summary, it is an urgent technical problem to be solved by those skilled in the art how to overcome the above-mentioned defects of the conventional gas measuring device.

Disclosure of Invention

The invention aims to provide a gas measuring device, which solves the technical problem that the gas measuring device in the prior art is difficult to measure the gas with low cleanliness.

In order to solve the above problems, the present invention provides a gas measuring apparatus including a sensor chip, a closed pipe, and an impurity collector and diffuser.

And the two ends of the closed pipeline are respectively provided with a gas inlet and a gas outlet, and the impurity collector and the sensing chip are arranged in the closed pipeline and are sequentially arranged along the gas flow direction.

The impurity collector and disperser is provided with a plurality of blades, the blades are sequentially arranged along the circumferential direction around the central axis of the closed pipeline, the blades are provided with turnover parts, and the included angles of the turnover parts and the radial cross sections of the closed pipeline are acute angles.

Preferably, as an implementation mode, the impurity collector and diffuser further has a frame and a central disk, two ends of the blade are respectively connected with the frame and the central disk, and the frame is in sealing fit with the inner wall of the closed pipeline.

Preferably, as an implementable mode, the blade further has a flat blocking portion, the flat blocking portion is parallel to a radial cross section of the closed pipeline, an airflow channel is formed in the flat blocking portion, the folded portion is opposite to the airflow channel, and the folded portion is folded and folded in the airflow direction from the flat blocking portion.

Preferably, as an implementation mode, the width of the folded part and the width of the airflow channel are gradually increased from the central disc to the frame.

Preferably, as an implementation manner, the flat blocking part is a fan-shaped structure with a triangular window, the triangular window forms the airflow channel, the folded part is triangular, the triangular window and the folded part are identical in shape and size, a first ratio of an angle of the folded part close to the central disc to an angle of a central angle of the fan shape ranges from 3/4 to 4/5, and preferably the first ratio is 3/4;

and/or the included angle between the turning part and the radial section of the closed pipeline is 10-80 degrees, preferably 30-60 degrees, and most preferably 30-45 degrees;

and/or the blades are uniformly distributed along the circumferential direction, the number of the blades ranges from 10 to 20, and the number of the blades is preferably 16;

and/or the central disc is a solid disc, or the central disc is a mesh disc with the mesh number of more than or equal to 100 meshes;

and/or the impurity collector and distributor is arranged at the gas inlet or a part close to the gas inlet;

and/or the impurity collector and diffuser is made of stainless steel, aluminum alloy or engineering plastics.

Preferably, as an implementation mode, an impurity collecting tank is disposed on an inner wall of the closed pipeline, and the impurity collecting tank is located between the impurity collector and the sensing chip.

Preferably, as an embodiment, the depth of the impurity collecting tank is gradually increased in a vertical direction.

Preferably, as an implementation mode, a second ratio of the depth of the bottommost end of the impurity collecting tank to the depth of the topmost end of the impurity collecting tank ranges from 1 to 4, and preferably the second ratio ranges from 2 to 3; and/or the roughness of the bottom of the impurity collecting groove is greater than or equal to 10 mu m.

Preferably, as an embodiment, the shape of the outer edge of the rim and the shape of the central disc are both circular.

The distance between the impurity collecting grooves and the impurity collecting and dispersing device is a first distance, a third ratio of the first distance to the outer diameter of the frame ranges from 1/20 to 1/5, and the third ratio is 1/10 preferably; and/or a fourth ratio of the width of the impurity collecting groove to the outer diameter of the frame ranges from 1/10 to 1/2, and the fourth ratio is 1/4; and/or the range of a fifth ratio of the depth of the impurity collecting groove to the outer diameter of the frame is 1/20-1/10; and/or a sixth ratio of the diameter of the central disc to the outer diameter of the frame ranges from 1/10 to 1/4, preferably the sixth ratio is 1/5; and/or a seventh ratio of the width of the frame to the outer diameter of the frame ranges from 1/12 to 1/10, and the seventh ratio is 1/12.

Preferably, as an implementation manner, a gas rectifier and a flow field distribution regulator are sequentially installed in the closed pipeline along the gas flow direction, and both the gas rectifier and the flow field distribution regulator are located between the impurity collector and the sensing chip.

Preferably, as an implementable mode, still install the reposition of redundant personnel component in the closed conduit, the reposition of redundant personnel component includes a plurality of shunt tubes of establishing of overlapping in proper order, and is a plurality of the shunt tubes all with closed conduit coaxial setting, sensor chip is located most central point position intraductal central point of shunt tubes.

Preferably, as an embodiment, the closed conduit has a circular cross-section.

The distance between any two adjacent shunt tubes is smaller than or equal to the inner diameter of the shunt tube at the most central position; and/or an eighth ratio of an inner diameter of a single grid in the gas rectifier to an inner diameter of the enclosed conduit is 1/25; and/or the length of the gas rectifier is equal to the inner diameter of the closed pipeline; and/or a ninth ratio of the thickness of the flow field distribution regulator to the inner diameter of the closed pipe ranges from 1/8 to 1/2, preferably the ninth ratio is 1/4; a plurality of circular holes are uniformly distributed on the flow field distribution regulator, the tenth ratio of the diameter of each circular hole to the inner diameter of the closed pipeline ranges from 1/16 to 1/4, and the preferred tenth ratio is 1/5; and/or the material of the gas rectifier is stainless steel or engineering plastics; and/or the distance between the gas rectifier and the flow field distribution regulator is a second distance which is half of the inner diameter of the closed pipeline; and/or the distance between the flow dividing component and the flow field distribution regulator is a third distance, the range of an eleventh ratio of the third distance to the inner diameter of the closed pipeline is 1-3, and preferably the eleventh ratio is 2; and/or the twelfth ratio of the pipe diameter of the centermost shunt pipe to the inner diameter of the closed pipeline ranges from 1/10 to 1/5, and the twelfth ratio is 1/7 preferably; and/or a thirteenth ratio of the axial length of the flow dividing member to the axial length of the closed conduit ranges from 1/4 to 1/2, preferably the thirteenth ratio is 1/3; and/or the wall thickness of the shunt tube ranges from 2 mm to 5mm, and preferably the wall thickness of the shunt tube is 2.5 mm.

Preferably, as an implementation mode, the gas measurement device further includes a control module electrically connected to the sensor chip.

The gas measuring device further comprises a display, the control module is electrically connected with the display, and the display is used for displaying measured data; and/or the gas measurement device further comprises a communication module, the communication module is electrically connected with the control module, and the communication module is used for sending measurement data to the control host or the cloud processing center; and/or, the gas measuring device further comprises a storage module, the storage module is electrically connected with the control module, and the storage module is used for storing the obtained measuring data.

Preferably, as an implementation mode, the control module, the display, the communication module and the storage module are all installed outside the closed pipeline, and the gas measuring device further includes a cover that is fastened on an outer wall of the closed pipeline and forms a sealed cavity in sealing fit with the closed pipeline; the control module, the display, the communication module and the storage module are all located in the sealed cavity.

Preferably, as an implementation manner, the sensing chip is mounted on a carrier, and a wire for connecting the control module and the sensing chip is disposed on the carrier; the closed pipeline is provided with an insertion hole, the bearing piece can be inserted into the closed pipeline through the insertion hole, and the bearing piece is in sealing fit with the insertion hole.

Preferably, as an embodiment, the gas measuring apparatus further includes a printed circuit board for carrying the sensor chip, and the sensor chip has a silicon substrate.

The sensing chip comprises a flow sensor, the flow sensor comprises a first heat insulation cavity, a micro heater and a plurality of thermistors, the first heat insulation cavity is formed in the silicon substrate, a first heat insulation film covers the first heat insulation cavity, the micro heater and the thermistors are both arranged on the first heat insulation film, and the thermistors are electrically connected with the printed circuit board through a first connecting wire and a first bonding pad; and/or the sensing chip comprises a pressure sensor, the pressure sensor comprises a second heat insulation cavity and a plurality of piezoresistors, the second heat insulation cavity is formed in the silicon substrate, a second heat insulation film covers the second heat insulation cavity, the piezoresistors are arranged on the second heat insulation film, and the piezoresistors are electrically connected with the printed circuit board through second connecting wires and second bonding pads; and/or the sensing chip comprises a temperature sensor, the temperature sensor is arranged on the silicon substrate, and the temperature sensor is electrically connected with the printed circuit board through a third connecting wire and a third bonding pad.

Compared with the prior art, the invention has the beneficial effects that:

the invention provides a gas measuring device, which comprises a sensing chip (namely a micro-electro-mechanical system thermal flow sensing chip), a closed pipeline and an impurity collector-diffuser, wherein a gas inlet and a gas outlet are respectively arranged at two ends of the closed pipeline, the impurity collector-diffuser and the sensing chip are both arranged in the closed pipeline, and the impurity collector-diffuser and the sensor chip are sequentially arranged along the gas flow direction, so that gas flow can firstly pass through the impurity collector-diffuser after entering the closed pipeline from the gas inlet and then can reach the position of the sensing chip.

Be provided with a plurality of blades in the concrete structure of above-mentioned impurity collector, be equipped with the turnover portion on the blade, this turnover portion is the acute angle with the contained angle of the radial cross-section of closed pipeline, thereby, the blade can lead impurity (particulate matter) in the air current, change the flow direction of impurity, make impurity can flow towards the pipe wall of closed pipeline along the blade, thereby, impurity can contact with the pipe wall of closed pipeline, and under the effect of the friction power of pipe wall, the speed descends, no longer follow the air current and flow, but be detained in closed pipeline, thus, impurity and gaseous separation has been realized, through the purer gas of separation impurity, can flow to the sensing chip, thereby, can reduce the impurity content in the air current with sensing chip contact, impurity has been got rid of completely even, so, the sensing chip is just convenient.

Therefore, the gas measuring device provided by the invention can measure the gas with low cleanliness and has a wide application range.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a schematic perspective view of a gas measurement device according to an embodiment of the present invention;

fig. 2 is an exploded view of a gas measuring device according to an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view showing a partial structure of a gas measuring apparatus according to an embodiment of the present invention;

fig. 4 is a schematic perspective view of an impurity collector and diffuser in the gas measuring apparatus according to the embodiment of the present invention;

FIG. 5 is a schematic view showing a partial structure of an impurity collector and diffuser in a gas measuring apparatus according to an embodiment of the present invention;

fig. 6 is an exploded view of a shunt member, a carrier and a sensor chip in the gas measurement device according to the embodiment of the present invention;

fig. 7 is a sectional view showing an assembly structure of a separation member, a carrier, and a sensor chip in a gas measurement device according to an embodiment of the present invention;

fig. 8 is a schematic perspective view of a sensor chip in the gas measuring device according to the embodiment of the present invention.

Description of reference numerals:

100-a sensing chip; a 110-silicon substrate; 120-a flow sensor; 121-a first insulating chamber; 122-a thermistor; 123-a first connection; 124-first bonding pad; 130-a pressure sensor; 131-a second insulating chamber; 132-a piezoresistor; 133-a second link; 134-second pad; 140-a temperature sensor; 141-third connecting line; 142-a third pad;

200-closing the pipeline; 210-a gas inlet; 220-gas outlet; 230-an impurity collection tank; 240-jack; 250-a first threaded connection;

300-impurity collector and disperser; 310-a blade; 311-fold over; 312-a plateau; 320-frame; 330-a central disc;

410-a gas rectifier; 420-a flow field distribution adjuster;

500-a flow-splitting member; 510-a shunt tube; 520-a stabilizing member;

610-a control module; 620-a communication module; 630-an industrial cable;

700-buckling cover; 710-a second threaded connection;

800-a carrier; 810-boss;

910-a sealing station; 920-sealing and pressing the blocks.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "vertical", "horizontal", and the like indicate orientations or positional relationships based on those shown in the drawings, which are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted" and "connected" are to be interpreted broadly, e.g., as being either fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The present invention will be described in further detail below with reference to specific embodiments and with reference to the attached drawings.

Referring to fig. 1 to 7, the present embodiment provides a gas measurement apparatus, which includes a sensing chip 100 (i.e., a mems thermal flow sensing chip 100), a closed conduit 200, and an impurity collector-diffuser 300, wherein two ends of the closed conduit 200 are respectively provided with a gas inlet 210 and a gas outlet 220, the impurity collector-diffuser 300 and the sensing chip 100 are both installed in the closed conduit 200, and the impurity collector-diffuser 300 and the sensing chip are sequentially arranged along a gas flow direction (i.e., a direction indicated by arrows in fig. 1 and 2), so that after entering the closed conduit 200 from the gas inlet 210, a gas flow firstly passes through the impurity collector-diffuser 300 and then reaches the sensing chip 100.

Referring to fig. 3-5, in the specific structure of the impurity collector 300, a plurality of blades 310 are provided, a folded portion 311 is provided on each blade 310, an included angle between the folded portion 311 and the radial cross section of the closed pipe 200 is an acute angle, so that the blades 310 can guide impurities (particles) in the gas flow, change the flow direction of the impurities, and enable the impurities to flow along the blades 310 toward the pipe wall of the closed pipe 200, so that the impurities can contact with the pipe wall of the closed pipe 200, and under the friction force of the pipe wall, the impurities are reduced in speed, no longer flow along the gas flow, but remain in the closed pipe 200, thus the impurities and the gas are separated, and the purer gas from which the impurities are separated can flow to the sensor chip 100, thereby reducing the impurity content in the gas flow contacting the sensor chip 100, even completely removing the impurities, the sensor chip 100 is not easily damaged.

Therefore, the gas measurement device provided in the present embodiment can measure a gas with low cleanliness, and has a wide range of applications.

Referring to fig. 1-3, the gas inlet 210 and the gas outlet 220 may be provided with a threaded connector (female or male) or a flange via a first threaded connector 250.

Referring to fig. 3 and 4, in the specific structure of the impurity collector 300, a frame 320 and a central disk 330 are further provided, two ends of the blade 310 are respectively connected to the frame 320 and the central disk 330, and the frame 320 is in sealing fit with the inner wall of the closed pipeline 200, so that the central disk 330 can block impurities in the gas flow with the highest flow rate in the central region of the closed pipeline 200 and prevent the impurities from entering the closed pipeline 200, thereby preventing the impurities from being adsorbed onto the inner wall of the closed pipeline 200 due to the too high flow rate, preventing the impurities from reaching the sensing chip 100 along with the gas and damaging the sensing chip 100, and being applicable to the gas with a high flow rate.

Specifically, referring to fig. 2, the frame 320 and the inner wall of the enclosed conduit 200 may be sealingly engaged by a first sealing ring.

Referring to fig. 3 to 5, in the specific structure of the blade 310, a flat blocking portion 312 is further provided, the flat blocking portion 312 is parallel to the radial cross section of the closed pipe 200, an airflow channel is formed on the flat blocking portion 312, the folded portion 311 is opposite to the airflow channel, and the folded portion 311 is folded from the flat blocking portion 312 toward the airflow direction, so that part of impurities in the airflow is firstly blocked by the flat blocking portion 312, flows toward the airflow channel along the flat blocking portion 312, and then flows toward the pipe wall of the closed pipe 200 along the folded portion 311; other impurities directly enter the airflow channel and flow to the wall of the closed pipeline 200 along the folded part 311, so that the impurities in the airflow can flow to the wall of the closed pipeline 200 more smoothly, the content of the impurities in the airflow flowing to the sensing chip 100 can be further reduced, and the sensing chip 100 is less prone to damage.

Preferably, referring to fig. 5, the width of the folded portion 311 and the width of the airflow channel are set to be gradually increased from the central disc 330 to the frame 320, so that impurities in the airflow can more easily flow to the wall of the closed pipe 200, and the effect of removing the impurities is better.

Specifically, the blade 310 may be configured to have a fan-shaped structure with a triangular window, the triangular window may form the airflow channel, and accordingly, the folded portion 311 may be configured to be triangular, and the shape and size of the triangular window and the folded portion 311 may be configured to be the same, and a ratio of an angle of the folded portion 311 near the central plate 330 to an angle of the fan-shaped circle may be defined as a first ratio, which may be set to 3/4 to 4/5, and is preferably set to 3/4, so that a good impurity separation effect may be ensured on the premise of a small pressure loss.

The blade 310 may be a unitary structure, that is, the folded portion 311 may be formed by folding after cutting a flat plate, and the unfolded portion forms the flat portion 312.

Specifically, the range of the included angle between the folded portion 311 and the radial cross section of the closed duct 200 is set to 10 ° to 80 °, preferably 30 ° to 60 °, and most preferably 30 ° to 45 °, so as to ensure a better guiding effect and reduce pressure loss.

Alternatively, the blades 310 are uniformly distributed in the circumferential direction, so that the airflow can be uniformly distributed to the airflow passage of each blade 310, so that the airflow distribution is more uniform.

Specifically, the number of the blades 310 may be set to any one of 10 to 20, and preferably 16.

The central disc 330 may be a solid disc or a mesh disc, and when the central disc 330 is a mesh disc, the mesh number of the mesh is not less than 100 meshes, so as to ensure the blocking effect of the central disc 330 on the impurities.

Preferably, referring to fig. 3, the impurity collector 300 is installed at the gas inlet 210 of the closed duct 200 or at a position close to the gas inlet 210, so that it is possible to facilitate shortening the axial size of the closed duct 200, reducing costs, and reducing the requirement for installation space.

The impurity collector 300 may be made of stainless steel, aluminum alloy or engineering plastic, so that the impurity collector 300 has high strength and is not deformed by the impact of air flow.

Preferably, referring to fig. 3, an impurity collecting groove 230 may be formed on an inner wall of the closed conduit 200, and the impurity collecting groove 230 is disposed between the impurity collector 300 and the sensor chip 100, so that impurities in the air flow may flow into the impurity collecting groove 230 under the guiding action of the blade 310, and be blocked by the impurity collecting groove 230 and be retained in the impurity collecting groove 230, so as to avoid the impurities from accumulating in the flow channel, and thus, the problem of influence on the reliability of the measurement due to the flow of the impurities accumulating in the flow channel in the closed conduit 200 may be alleviated or eliminated.

Preferably, the depth of the impurity collecting groove 230 is gradually increased in the vertical direction.

It should be noted that, in the process that the impurities in the air flow are accumulated in the impurity collecting tank 230, the impurities may slide down along the impurity collecting tank 230 due to their own gravity, that is, the amount of the impurities accumulated at the bottom of the impurity collecting tank 230 may be higher than the amount of the impurities accumulated at the top, so that the depth of the bottom of the impurity collecting tank 230 is set to be deeper, the impurity containing amount at the bottom of the impurity collecting tank 230 may be increased, and the impurities may be prevented from overflowing into the flow channel of the closed pipeline 200.

In practice, the closed pipe 200 is generally horizontally disposed in the axial direction, so that the depth of the impurity dispersing groove 230 gradually increases from top to bottom along the circumferential direction.

Specifically, the ratio of the depth of the lowermost end of the impurity collecting tank 230 to the depth of the uppermost end of the impurity collecting tank 230 may be defined as a second ratio, and the second ratio may be set in the range of 1 to 4, preferably 2 to 3.

The roughness of the bottom of the impurity collecting groove 230 is set to be greater than or equal to 10 μm, so that the bottom of the impurity collecting groove 230 can more reliably adsorb impurities, preventing the impurities from escaping into the flow passage.

Specifically, referring to fig. 3 and 4, the outer edge of the frame 320 of the impurity collector and diffuser 300 and the central disk 330 are both circular, but since the impurity collector and diffuser 300 is hermetically fitted to the inner wall of the closed pipe 200, the inner wall of the closed pipe 200 is also circular in cross section and has a diameter identical to that of the outer edge of the frame 320 of the impurity collector and diffuser 300.

The distance between the impurity collecting tank 230 and the impurity disperser 300 is defined as a first distance (i.e. the distance between the end of the impurity collecting tank close to the gas inlet and the impurity disperser), the ratio of the first distance to the outer diameter of the frame 320 of the impurity disperser 300 is defined as a third ratio, the range of the third ratio is set to 1/20-1/5, and the third ratio is preferably set to 1/10, so that the impurity collecting tank 230 can not only effectively collect the impurities separated from the gas flow, but also facilitate the cleaning of the impurities in the impurity collecting tank 230 from the gas inlet 210 of the closed pipeline 200, and in addition, the influence of the impurity collecting tank 230 on the installation and stability of the impurity disperser 300 can be reduced.

Define the ratio of the width of impurity collecting vat 230 and the external diameter of frame 320 of impurity ware 300 for the fourth ratio, set up the scope of fourth ratio into 1/10 ~ 1/2, preferably set up the fourth ratio into 1/4, so, guarantee from the air current in the impurity of separating get into the impurity collecting vat 230 on the basis smoothly, can shorten the axial length who seals pipeline 200, and therefore, the cost is reduced, and the requirement to the installation space is reduced, furthermore, can also reduce the influence of impurity collecting vat 230 to the installation and the stability of impurity ware 300 that scatters.

The ratio of the depth of the impurity collecting groove 230 to the outer diameter of the rim 320 of the impurity collector 300 is defined as a fifth ratio, and the range of the fifth ratio is set to 1/20-1/10, so that the impurity collecting groove 230 has a sufficient impurity containing amount. If the depths of the respective portions of the impurity collecting grooves 230 are set to be uniform, it is preferable that the ratio (fifth ratio) of the depth of the impurity collecting grooves 230 to the outer diameter of the rim 320 of the impurity collector 300 is set to 1/15.

The ratio of the diameter of the central disc 330 of the impurity collector/diffuser 300 to the outer diameter of the frame 320 is defined as a sixth ratio, the range of the sixth ratio is set to 1/10-1/4, and the sixth ratio is preferably set to 1/5, so that the blocking area of the central disc 330 for fast impurities can be enlarged on the premise of less influence on pressure loss, and the fast impurities are prevented from entering the flow channel of the closed pipeline 200.

The ratio of the width of the frame 320 of the impurity collector and diffuser 300 to the outer diameter of the frame 320 is defined as a seventh ratio, the range of the seventh ratio is 1/12-1/10, and the seventh ratio is preferably 1/12, so that the pressure loss of the frame 320 to the airflow is reduced as much as possible on the premise of ensuring the strength of the frame 320 of the impurity collector and diffuser 300.

Referring to fig. 2 and 3, the gas measurement device provided in this embodiment is further provided with a gas rectifier 410 and a flow field distribution regulator 420, the gas rectifier 410 and the flow field distribution regulator 420 are installed in the closed pipe 200 along the gas flow direction, and the gas rectifier 410 and the flow field distribution regulator 420 are both disposed between the impurity collector-diffuser 300 and the sensor chip 100, so that the gas flow from which the impurities are removed by the impurity collector-diffuser 300 can sequentially flow through the gas rectifier 410 and the flow field distribution regulator 420, and then reaches the region where the sensor chip 100 is located.

It should be noted that the gas rectifier 410 can eliminate unstable states in the gas flow, such as pulsating flow, etc., and the flow field distribution regulator 420 can make the flow field distribution of the gas have stability and repeatability, thereby improving the accuracy of the measured value of the sensor chip 100.

Further, referring to fig. 2, 3, 6 and 7, a shunt member 500 may be installed in the closed tube 200, a plurality of shunt tubes 510 sequentially sleeved are provided in a specific structure of the shunt member 500, the plurality of shunt tubes 510 are all coaxially provided with the closed tube 200, and the sensor chip 100 is disposed at a central portion within the tube of the shunt tube 510 at the most central position.

It should be noted that the flow dividing member 500 can divide the flow field, so that the flow field is more stable, the repeatability of the gas flow field can be further improved, the flow velocity of the flow field in the centermost shunt tube 510 is fastest, most stable and most uniform, and the external disturbance is small, so that the sensor chip 100 is arranged in the center of the centermost shunt tube 510, and the high-precision measurement of the gas performance, such as mass flow, pressure, temperature and the like, can be reliably performed, and is particularly suitable for the industrial gas with a fast flow velocity.

Specifically, the shunt member 500 is fixed inside the closed pipe 200 by using the stabilizing member 520, and the stabilizing member 520 may be a sleeve which is sleeved outside the shunt member 500; the stabilizing member 520 can be in sealing engagement with the inner wall of the closed conduit 200 by a sealing ring.

Preferably, the spacing between any two adjacent shunt tubes 510 is set to be less than or equal to the inner diameter of the most centrally located shunt tube 510.

Specifically, the cross section of the closed duct 200 is provided in a circular shape.

The gas rectifier 410 is made of a grid, and the ratio of the inner diameter of the single grid to the inner diameter of the closed duct 200 is defined as an eighth ratio, which is set to 1/25.

Preferably, the length of the gas rectifier 410 is set to be equal to the inner diameter of the closed conduit 200, so that the length of the gas rectifier 410 is maintained at a small size on the premise of ensuring the rectifying effect of the gas rectifier 410, thereby shortening the length of the closed conduit 200, reducing the cost, and reducing the requirement for installation space.

The ratio of the thickness of the flow field distribution adjuster 420 to the inner diameter of the closed duct 200 is defined as a ninth ratio, the range of the ninth ratio is set to 1/8-1/2, and the ninth ratio is preferably set to 1/4, so that a better flow field distribution adjusting effect can be obtained, and the air flow is more stable.

A plurality of circular holes are uniformly distributed on the flow field distribution adjuster 420 to achieve the effect of adjusting the flow field distribution, the ratio of the diameter of the circular hole to the inner diameter of the closed pipe 200 is defined as a tenth ratio, the tenth ratio is set to be in the range of 1/16-1/4, and the tenth ratio is preferably set to be 1/5, so that a better adjusting effect can be obtained.

Preferably, stainless steel or engineering plastic is used as the material of the gas rectifier 410, so that the gas rectifier 410 has sufficient strength and is not deformed by the impact of the gas flow.

It is preferable that the distance between the gas rectifier 410 and the flow field distribution regulator 420 is defined as a second distance, and the second distance is set to be half of the inner diameter of the closed duct 200, so that the distance is compressed as much as possible on the basis of controlling the probability of turbulence generation between the gas rectifier 410 and the flow field distribution regulator 420 to a low value, to shorten the length of the closed duct 200, to reduce the cost, and to reduce the requirement for installation space.

The distance between the flow dividing member 500 and the flow field distribution adjuster 420 is defined as a third distance, the ratio of the third distance to the inner diameter of the closed pipe 200 is defined as an eleventh ratio, the range of the eleventh ratio is set to 1-3, and the eleventh ratio is preferably set to 2, so that the distance is compressed as much as possible on the basis of controlling the probability of generating turbulence between the flow dividing member 500 and the flow field distribution adjuster 420 to be a lower value, thereby shortening the length of the closed pipe 200, reducing the cost, and reducing the requirement on the installation space.

The ratio of the pipe diameter of the centermost shunt pipe 510 to the inner diameter of the closed pipeline 200 is defined as a twelfth ratio, the range of the twelfth ratio is set to be 1/10-1/5, and the twelfth ratio is preferably set to be 1/7, so that the distribution of the flow field is more stable and the repeatability is higher on the premise of smaller pressure loss, and therefore, the measurement precision is improved.

The ratio of the axial length of the flow dividing member 500 to the axial length of the closed conduit 200 is defined as a thirteenth ratio, the thirteenth ratio is set in the range of 1/4-1/2, and preferably the thirteenth ratio is set in the range of 1/3, and the purpose of the arrangement is to further compress the size of the flow channel passing through the gas measurement sensor, so that the distribution of the flow field is more stable and the repeatability is improved, and the measurement with high precision is ensured.

Set up the scope of shunt tubes 510's wall thickness to 2 ~ 5mm, preferably set up shunt tubes 510's wall thickness to 2.5mm, so, can guarantee shunt tubes 510's intensity, make shunt tubes 510 difficult by the frayed, guarantee shunt tubes 510's structural stability and reliability, but also can not stop gas flow because of too thick, can reduce the probability of producing the torrent.

Referring to fig. 2, in the specific structure of the gas measuring device provided in this embodiment, a control module 610 is further provided, and the control module 610 is electrically connected to the sensor chip 100, so that the control module 610 is used to digitize and quantify information collected by the sensor chip 100, which is convenient for further transmission or storage.

The display can be added to electrically connect the display with the control module 610, so that the control module 610 can transmit the measured data to the display, and the measured data is displayed by the display and visually checked by a worker.

The communication module 620 may be further added to electrically connect the communication module 620 with the controller, so that the control module 610 can transmit the measurement data to the communication module 620, and the communication module 620 is used to transmit the measurement data to the control host or the cloud processing center.

Specifically, the communication module 620 may send the measurement data to the control host or the cloud processing center in a wired manner; and the measurement data can be sent to the control host or the cloud processing center in a wireless mode such as Bluetooth, Zigbee, LoRa and infrared transmission.

The remote data communication preferably operates over communication standard protocols such as NB-IoT or GPRS or others depending on the installation of the gas meter.

The storage module can be additionally arranged and electrically connected with the control module 610, so that the control module 610 can transmit the measurement data to the storage module, and the acquired measurement data can be stored by the storage module for later retrieval.

Specifically, a plurality of identical data storage units may be provided to secure data.

Preferably, the control module 610, the display, the communication module 620 and the storage module are all installed outside the closed conduit 200 to prevent the modules from affecting the flow passage inside the closed conduit 200; on the basis, the buckle cover 700 is additionally arranged, the buckle cover 700 is buckled on the outer wall of the closed pipeline 200, and the buckle cover 700 and the closed pipeline 200 are in sealing fit to form a sealing cavity, so that a sealing space can be formed between the buckle cover 700 and the closed pipeline 200, the control module 610, the display, the communication module 620 and the storage module are all arranged in the sealing cavity between the buckle cover 700 and the closed pipeline 200, so that the protection requirement of the industrial environment can be met, a complete and independent measuring device can be formed, and the integrity is strong.

Specifically, the fastening cover 700 may be fastened to the closed pipe 200 by a plurality of second threaded connectors 710, and meanwhile, a sealing ring may be disposed between the fastening cover 700 and the closed pipe 200, so that the fastening cover 700 and the closed pipe 200 are in sealing engagement with each other.

An operator keypad may be provided on the flap 700 and connected to the control module 610 for password control of local flow meter parameter settings, data access, diagnostics, and third party calibration or meter correction via the operator keypad.

When the communication module is connected to the control host or the cloud processing center in a wired manner, the communication module may be connected to the industrial cable 630 running through the cover 700.

On the basis of the above structure, referring to fig. 3, 6 and 7, the sensor chip 100 may be mounted on the carrier 800, and the carrier 800 is provided with a wire for connecting the control module 610 and the sensor chip 100, and accordingly, the insertion hole 240 is formed on the closed conduit 200, so that the carrier 800 can be inserted into the closed conduit 200 through the insertion hole 240, and the carrier 800 and the insertion hole 240 are hermetically engaged, so that the wire provided on the carrier 800 can connect the sensor chip 100 inside the closed conduit 200 and the control module 610 outside the closed conduit 200.

It should be noted that, the bearing member 800 is in sealing fit with the insertion hole 240, so that the sealing performance of the closed pipeline 200 can be ensured, and good measurement accuracy can be ensured; in addition, the bearing piece 800 is matched with the closed pipeline 200 in a plugging mode, so that the assembly difficulty can be reduced, and the assembly time can be saved.

Specifically, referring to fig. 2, 6 and 7, a boss 810 may be provided on the carrier 800, and, at the same time, a sealing stage 910 and a sealing press 920 are added, the sealing table 910 and the sealing press block 920 are both provided with a clearance hole for the bearing member 800 to pass through, the cross-sectional area of the clearance hole is smaller than the cross-sectional area of the boss 810 of the carrier 800, so that the boss 810 of the carrier 800 cannot pass through the clearance hole, during assembly, the sealing platform 910 is first fixedly installed on the portion of the closed conduit 200 corresponding to the insertion hole 240 (the sealing platform 910 may also be integrated with the closed conduit 200), the carrier 800 is then inserted into the insertion hole 240 of the enclosed conduit 200 through the through-hole of the sealing station 910, until the boss 810 on the carrier 800 contacts the sealing station 910, and is blocked by the sealing platform 910, at this time, the carrier 800 is inserted in place, and the sensing chip 100 is just located at the central position in the closed conduit 200; then, the through hole on the sealing pressing block 920 is directly opposite to the bearing piece 800 and is put down, so that the bearing piece 800 is inserted into the through hole of the sealing pressing block 920 until the sealing pressing block 920 contacts with the sealing table 910, and the sealing pressing block 920 is fixed on the sealing table 910, at this time, the boss 810 on the bearing piece 800 is clamped between the sealing pressing block 920 and the sealing table 910, so that not only the sealing effect on the closed pipeline 200 is realized, but also the sealing pressing block 920 and the sealing table 910 also realize the fixation on the bearing piece 800.

Referring to fig. 8, a printed circuit board for carrying the sensor chip 100 may be further provided in the gas measuring apparatus provided in the present embodiment, and a silicon substrate 110 may be provided in the specific structure of the sensor chip 100.

Any one or more of the flow sensor 120, the pressure sensor 130, and the temperature sensor 140 may be integrated on the sensing chip 100.

The flow sensor 120 includes a first insulating chamber 121 formed on the silicon substrate 110, a micro-heater, and a plurality of thermistors 122, wherein a first insulating film covers the first insulating chamber 121, the micro-heater and the thermistors 122 are both disposed on the first insulating film, and the thermistors 122 are electrically connected to the printed circuit board through a first connecting line 123 and a first bonding pad 124.

The flow sensor 120 uses a thermal mass flow meter principle, and drives any one of the thermistors 122 using modulated heat waves, and simultaneously acquires the timing and amplitude of heat wave conduction at the remaining thermistors 122, and connects a signal to a printed circuit board through a first connection line 123 and a first pad 124, thereby obtaining information on a desired mass flow rate and gas composition.

The number of the thermistors 122 may be three, the three thermistors 122 are sequentially arranged on the first heat insulation film, and the interval between two adjacent first heat insulation films is preferably 5-300 μm.

The first heat insulation film may be made of parylene.

The thermistor 122 is preferably made of a stable metal with a high temperature coefficient (e.g., platinum or nickel) or a CMOS compatible material (e.g., doped polysilicon) and surface passivated with a highly thermally conductive material (e.g., silicon nitride or silicon carbide). The space between the micro-heater and each thermistor 122 is preferably 20 to 120 μm, and more preferably 40 to 60 μm.

The pressure flow sensor includes a second heat insulating chamber 131 opened on the silicon substrate 110 and a plurality of piezoresistors 132, a second heat insulating film is covered on the second heat insulating chamber 131, the piezoresistors 132 are disposed on the second heat insulating film, and the piezoresistors 132 are electrically connected to the printed circuit board through second wires 133 and second pads 134.

The pressure sensor 130 uses the measurement principle of the piezoresistors 132, when the gas pressure in the closed pipe 200 is applied to and deforms the second thermal insulation film, the piezoresistors 132 are simultaneously deformed, and the deformation generates an electric signal, which is transmitted to the printed circuit board through the second connection line 133 and the second pad 134, so as to obtain the information of the required gas pressure.

The number of the piezoresistors 132 is four, the second heat insulation cavity 131 is a rectangular parallelepiped cavity, and the four piezoresistors 132 are respectively arranged in the middle of four edges of the cavity.

The piezoresistor 132 is preferably formed by diffusion doping.

The second heat insulation films are made of a composite material of silicon nitride and silicon oxide, and the thickness of the second heat insulation films is preferably 0.5-2 mu m.

The first thermal insulation chamber 121 and the second thermal insulation chamber 131 can be manufactured by plasma deep etching.

The temperature sensor 140 is disposed on the silicon substrate 110 and may be electrically connected to the printed circuit board through a third wire 141 and a third pad 142 to acquire desired gas temperature information through the temperature sensor 140.

The temperature sensor 140 is preferably made of doped polysilicon, and its resistance value varies with the temperature, and is calibrated to obtain accurate temperature data.

The silicon substrate 110 is preferably made of an undoped monocrystalline silicon wafer material.

In summary, the embodiments of the present invention disclose a gas measurement device, which overcomes many technical defects of the conventional gas measurement device. The gas measuring device provided by the embodiment of the invention can measure the gas with low cleanliness and has a wide application range.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A gas measuring apparatus is characterized by comprising a sensor chip (100), a closed pipe (200) and an impurity collector/diffuser (300);

the two ends of the closed pipeline (200) are respectively provided with a gas inlet (210) and a gas outlet (220), and the impurity collector and diffuser (300) and the sensing chip (100) are both arranged in the closed pipeline (200) and are sequentially arranged along the direction of gas flow;

impurity collector and disperser (300) have a plurality of blades (310), blade (310) are wound the central axis of closed pipeline (200) is arranged along circumference in proper order, blade (310) have turn-over portion (311), turn-over portion (311) with the contained angle of the radial cross-section of closed pipeline (200) is the acute angle.

2. The gas measuring device according to claim 1, wherein the impurity collector (300) further includes a rim (320) and a central plate (330), both ends of the blade (310) are connected to the rim (320) and the central plate (330), respectively, and the rim (320) is in sealing engagement with an inner wall of the closed duct (200).

3. The gas measuring device according to claim 2, wherein the blade (310) further includes a flat portion (312), the flat portion (312) is parallel to a radial cross section of the closed duct (200), an airflow passage is formed in the flat portion (312), the folded portion (311) is opposed to the airflow passage, and the folded portion (311) is folded from the flat portion (312) in a direction of the airflow.

4. The gas measuring device according to claim 3, wherein the width of the folded portion (311) and the width of the gas flow passage are each gradually increased from the central plate (330) toward the rim (320).

5. The gas measuring device according to claim 4, wherein the flat portion (312) has a fan-shaped structure having a triangular window forming the gas flow passage, the folded portion (311) has a triangular shape, the triangular window and the folded portion (311) have the same shape and size, and a first ratio of an angle of the folded portion (311) near the central disk (330) to an angle of a central angle of the fan-shaped window is in a range of 3/4 to 4/5, preferably 3/4;

and/or the included angle between the turning part (311) and the radial section of the closed pipeline (200) is 10-80 degrees, preferably 30-60 degrees, and most preferably 30-45 degrees;

and/or the blades (310) are uniformly distributed along the circumferential direction, the number of the blades (310) ranges from 10 to 20, and preferably, the number of the blades (310) is 16;

and/or the central disc (330) is a solid disc, or the central disc (330) is a mesh disc with the mesh number larger than or equal to 100 meshes;

and/or the impurity collector and diffuser (300) is installed at the gas inlet (210) or a position close to the gas inlet (210);

and/or the impurity collector and diffuser (300) is made of stainless steel, aluminum alloy or engineering plastics.

6. A gas measuring device according to any one of claims 1 to 5, wherein an impurity collection groove (230) is formed on an inner wall of the closed conduit (200), and the impurity collection groove (230) is located between the impurity collector (300) and the sensor chip (100).

7. The gas measurement apparatus according to claim 6, wherein the depth of the impurity collection groove (230) is gradually increased in a vertical direction.

8. The gas measurement device according to claim 7, wherein a second ratio of a depth of a lowermost end of the impurity collecting tank (230) to a depth of an uppermost end of the impurity collecting tank (230) is in a range of 1 to 4, preferably in a range of 2 to 3; and/or the roughness of the bottom of the impurity collection tank (230) is greater than or equal to 10 [ mu ] m.

9. The gas measuring device according to claim 6, wherein the outer edge of the frame (320) and the central disk (330) are both circular;

the distance between the impurity collecting grooves (230) and the impurity collector-disperser (300) is a first distance, and a third ratio of the first distance to the outer diameter of the frame (320) is in the range of 1/20-1/5, preferably the third ratio is 1/10; and/or a fourth ratio of the width of the impurity collecting groove (230) to the outer diameter of the frame (320) ranges from 1/10 to 1/2, preferably the fourth ratio is 1/4; and/or a fifth ratio of the depth of the impurity collecting groove (230) to the outer diameter of the frame (320) ranges from 1/20 to 1/10; and/or a sixth ratio of the diameter of the central disc (330) to the outer diameter of the rim (320) ranges from 1/10 to 1/4, preferably the sixth ratio is 1/5; and/or a seventh ratio of the width of the frame (320) to the outer diameter of the frame (320) ranges from 1/12 to 1/10, and the seventh ratio is 1/12.

10. A gas measuring device according to any one of claims 1 to 5, wherein a gas rectifier (410) and a flow field distribution regulator (420) are installed in the closed duct (200) in this order in the gas flow direction, and both the gas rectifier (410) and the flow field distribution regulator (420) are located between the impurity collector and diffuser (300) and the sensor chip (100).

11. A gas measuring apparatus according to claim 10, wherein a flow dividing member (500) is further installed in the closed tube (200), the flow dividing member (500) includes a plurality of flow dividing tubes (510) which are sequentially fitted, the plurality of flow dividing tubes (510) are arranged coaxially with the closed tube (200), and the sensor chip (100) is located at a central portion of the flow dividing tubes (510) located at a most central position.

12. A gas measuring device according to claim 11, characterized in that the closed conduit (200) is circular in cross-section;

the distance between any two adjacent shunt tubes (510) is less than or equal to the inner diameter of the most central shunt tube (510); and/or an eighth ratio of an inner diameter of a single grid in the gas rectifier (410) to an inner diameter of the enclosed duct (200) is 1/25; and/or the length of the gas rectifier (410) is equal to the inner diameter of the closed pipe (200); and/or a ninth ratio of the thickness of the flow field distribution regulator (420) to the inner diameter of the closed conduit (200) ranges from 1/8 to 1/2, preferably the ninth ratio is 1/4; a plurality of circular holes are uniformly distributed on the flow field distribution regulator (420), the range of a tenth ratio of the diameter of the circular holes to the inner diameter of the closed pipeline (200) is 1/16-1/4, and the preferable tenth ratio is 1/5; and/or the material of the gas rectifier (410) is stainless steel or engineering plastics; and/or the gas rectifier (410) is spaced from the flow field distribution regulator (420) by a second spacing that is half of the inner diameter of the closed conduit (200); and/or the distance between the flow dividing component (500) and the flow field distribution regulator (420) is a third distance, and the eleventh ratio of the third distance to the inner diameter of the closed pipeline (200) is in the range of 1-3, preferably 2; and/or the twelfth ratio of the pipe diameter of the centermost shunt pipe (510) to the inner diameter of the closed pipeline (200) ranges from 1/10 to 1/5, preferably the twelfth ratio is 1/7; and/or a thirteenth ratio of the axial length of the flow dividing member (500) to the axial length of the closed conduit (200) ranges from 1/4 to 1/2, preferably the thirteenth ratio is 1/3; and/or the wall thickness of the shunt pipe (510) ranges from 2 mm to 5mm, and preferably the wall thickness of the shunt pipe (510) is 2.5 mm.

13. A gas measurement device according to any one of claims 1 to 5, further comprising a control module (610), wherein the control module (610) is electrically connected to the sensor chip (100);

the gas measuring device further comprises a display, the control module (610) is electrically connected with the display, and the display is used for displaying measured data; and/or, the gas metering device further comprises a communication module (620), the communication module (620) is electrically connected with the control module (610), and the communication module (620) is used for sending the metering data to a control host or a cloud processing center; and/or, the gas measurement device further comprises a storage module, wherein the storage module is electrically connected with the control module (610), and the storage module is used for storing the acquired measurement data.

14. The gas measurement device according to claim 13, wherein the control module (610), the display, the communication module (620) and the storage module are all mounted outside the closed conduit (200), and the gas measurement device further comprises a cover (700), wherein the cover (700) is fastened on the outer wall of the closed conduit (200) and is in sealing fit with the closed conduit (200) to form a sealed cavity; the control module (610), the display, the communication module (620), and the storage module are all located within the sealed cavity.

15. The gas measuring device according to claim 14, wherein the sensor chip (100) is mounted on a carrier (800), and a wire for connecting the control module (610) and the sensor chip (100) is provided on the carrier (800); the closed pipeline (200) is provided with a jack (240), the bearing piece (800) can be inserted into the closed pipeline (200) through the jack (240), and the bearing piece (800) is in sealing fit with the jack (240).

16. A gas measuring device according to any one of claims 1-5, further comprising a printed circuit board for carrying said sensor chip (100), said sensor chip (100) having a silicon substrate (110);

the sensing chip (100) comprises a flow sensor (120), the flow sensor (120) comprises a first heat insulation cavity (121), a micro heater and a plurality of thermistors (122) which are arranged on the silicon substrate (110), a first heat insulation film covers the first heat insulation cavity (121), the micro heater and the thermistors (122) are both arranged on the first heat insulation film, and the thermistors (122) are electrically connected with the printed circuit board through a first connecting wire (123) and a first bonding pad (124); and/or the sensing chip (100) comprises a pressure sensor (130), the pressure sensor (130) comprises a second heat insulation cavity (131) and a plurality of piezoresistors (132), the second heat insulation cavity (131) is formed in the silicon substrate (110), a second heat insulation film covers the second heat insulation cavity (131), the piezoresistors (132) are arranged on the second heat insulation film, and the piezoresistors (132) are electrically connected with the printed circuit board through second connecting lines (133) and second bonding pads (134); and/or the sensing chip (100) comprises a temperature sensor (140), the temperature sensor (140) is arranged on the silicon substrate (110), and the temperature sensor (140) is electrically connected with the printed circuit board through a third connecting line (141) and a third bonding pad (142).