TWM561196U - Embedded sensing module and sensing device - Google Patents

Abstract

An embedded sensing module includes a barrel and at least one piece of sensor. The cylinder surrounds a liquid flow tank, and the cylinder has a plurality of flow holes which are in communication with the liquid flow tank. At least one piece of sensor is embedded in the flow channel.

Description

Embedded sensing module and sensing device

The present invention relates to an embedded sensing module and a sensing device, and more particularly to an embedded sensing module and a sensing device having a chip sensor.

Due to the current awareness of environmental protection in the society, the ion concentration, temperature, pH, conductivity, light penetration, turbidity, biochemical oxygen demand and specific molecular content of the fluid flowing in the pipe are detected to understand Whether the properties and composition of the fluid in the pipe fittings meet the requirements.

At present, the nature and composition of the fluid in the pipe or the tank are mostly classified into off-line or on-line detection methods. The so-called off-line detection method is to take samples of the fluid through the setting of the branch and then bring it back to the laboratory for analysis. However, the sampled fluid has passed a period of time before the analysis, so the sensed information is not instantaneous information, and may be contaminated by contact with the outside during the process of transporting the sampled fluid, resulting in inaccurate fluid detection results. Some of them are based on online testing.

The sensing module currently used for the online detection method is directly disposed in the tube through which the fluid flows, and the sensor in the sensing module can only measure the single property in the fluid. If you want to measure multiple properties in the fluid at the same time, you need to integrate each sensor with different properties, so that the overall sensing module is too large and not easy to set on the pipe.

The present invention provides an embedded sensing module and a sensing device for solving the problem that the sensor of the prior art that simultaneously measures multiple properties of the fluid is too large to be easily mounted on the tube.

An embedded sensing module disclosed in one embodiment of the present invention includes a barrel and at least one piece of sensor. The cylinder surrounds a liquid flow tank, and the cylinder has a plurality of flow holes which are in communication with the liquid flow tank. At least one piece of sensor is embedded in the flow channel.

A sensing device disclosed in another embodiment of the present invention includes a first-class tube, a barrel, and at least one piece of sensor. The flow tube surrounds a liquid flow path. The cylinder surrounds a liquid flow tank, and the cylinder has a plurality of flow holes which are in communication with the liquid flow tank. At least one piece of sensor is embedded in the flow channel. Wherein, the barrel is detachably inserted into the flow tube such that at least one piece of the sensor communicates with the liquid flow path through the flow holes.

The above description of the present invention and the following description of the embodiments are intended to illustrate and explain the principles of the present invention and to provide a further explanation of the scope of the present application.

Please refer to Figure 1 to Figure 3. FIG. 1 is a perspective view of a sensing device according to a first embodiment of the present invention. Figure 2 is an exploded view of Figure 1. Figure 3 is a cross-sectional view of Figure 1.

The sensing device 10 of the present embodiment is used, for example, to detect properties such as sub-concentration, temperature, pH, conductivity, light transmittance, turbidity, biochemical oxygen demand, and content of specific molecules of the fluid in the flow tube 100.

The sensing device 10 includes a first-class tube 100, a barrel 200, a sealing ring 300, a first electrical connector 400, and a sheet-like sensor 500. The flow tube 100 surrounds a liquid flow path 110, and there is typically a flowing fluid within the liquid flow path 110. The flow tube 100 has an internal thread 120 for assembly of the barrel 200 as described later. The chip sensor 500 can be embedded in the barrel 200 to form an embedded sensing module.

The cylinder 200 surrounds a liquid flow tank 230, and the cylinder 200 has a plurality of flow holes 240 communicating with the liquid flow tank 230. In detail, the cylinder 200 includes a cylindrical portion 210 and an assembly portion 220 that are axially connected. The cylindrical portion 210 surrounds the liquid flow channel 230, and the flow holes 240 are respectively located in the cylindrical portion 210. The cylindrical portion 210 has two guiding grooves 211, and the two guiding grooves 211 are all located in the liquid flow groove 230. The two guide grooves 211 extend from the end of the column portion 210 away from the assembly seat portion 220 toward the assembly seat portion 220. The assembly seat 220 includes a body 221 and an assembly ring 222 , and the assembly ring 222 protrudes from the base 221 . The cylindrical portion 210 is connected to one end of the assembly ring 222 away from the base 221 . The assembly ring 222 has an outer wall surface 2221 and an externally threaded structure 2222, and the externally threaded structure 2222 is located on the outer wall surface 2221. The barrel 200 is detachably inserted into the flow tube 100 and screwed into the internal thread 120 of the flow tube 100 through the externally threaded structure 2222 of the assembly ring 222 to fix the barrel 200 to the flow tube 100.

The assembly ring 222 further has a groove 2223, the sleeve 2223 is located on the outer wall surface 2221, and the sleeve groove 2223 is located between the external thread structure 2222 and the seat body 221. The seal ring 300 is sleeved between the sleeve 221 and the flow tube 100 to prevent fluid from leaking from the joint of the seat body 221 of the barrel 200 and the flow tube 100. The first electrical connector 400 is disposed in the base 221 of the assembly base 220, and the opposite ends of the strip sensor 500 respectively correspond to the two guiding slots 211, and are guided by the two guiding slots 211 to be embedded in the liquid. The flow channel 230 is configured such that the sheet sensor 500 communicates with the liquid flow path 110 through the flow holes 240. The chip sensor 500 has a second electrical connector 510 , and the second electrical connector 510 is electrically connected to the first electrical connector 400 .

In this embodiment, the chip sensor 500 is fabricated by a micro-electromechanical process technology and a screen electrode printing technology, and the chip sensor 500 can be a sensor for measuring a single property of the fluid, or can be A multi-sensor that measures multiple properties of a fluid at the same time. In addition, the first electrical connector 400 is inserted through the waterproof package and embedded in the base 221 of the assembly base 220, and the seat 221 is disposed away from the end of the cylindrical portion 210 by the electric wire 11 and electrically connected to the first electrical connection. The device 400 is configured to provide power required by the chip sensor 500 and to transmit signals sensed by the chip sensor 500.

In the present embodiment, by the structure of the cylinder 200 and the flow hole 240 of the cylinder 200, the flow rate and pressure of the fluid originally flowing in the flow tube 100 can be slowed down, and the fluid enters the liquid flow tank 230 through the flow holes. The fluid flow rate and pressure become small to form a stable flow field, so that the sheet sensor 500 can be prevented from being damaged, and the accuracy and numerical stability of the properties and composition contents of the measuring fluid can be improved. Further, the diameter D1 of the flow holes 240, the inner diameter D2 of the tubular body 200, the distance L1 between the axially adjacent tubular holes 240 in the axial direction of the tubular body 200, and the length L2 of the tubular portion 210 can be further adjusted. The effect of lowering the speed and reducing the pressure in the flow tank 230 of the cylinder 200 will be described in detail below by simulation data.

First, the relationship between the diameter D1 of the flow holes 240 and the inner diameter D2 of the cylindrical body 200 will be described with simulation data. Please refer to FIG. 4 and FIG. 5 first. FIG. 4 is a flow chart of the average flow velocity of the flow channel formed by the orifices of FIG. 3 at different diameters. Figure 5 is a flow field average pressure line diagram of the flow channel formed by the orifice of Figure 3 at different diameters.

The inner diameter D2 of the cylinder 200 is 50 mm, the tube length L2 of the cylinder portion 210 is 100 mm, and the distance between the two second holes 240 in the axial direction of the cylinder 200 is 20 mm, and the length L of the flow field is L. It is 300 mm, the width W is 100 mm, the height H is 100 mm, the inlet flow velocity of the flow field is 10 m/s, and the viscosity coefficient of the fluid is 1×10 ^-3 Pa. S is the simulated flow condition and the change in flow rate and pressure below the diameter of the different orifices 240 is observed.

4 and 5, as the diameter D1 of the flow holes 240 is changed from 2 mm to 10 mm, the flow velocity of the fluid in the flow channel 230 increases with the diameter D1 of the flow hole 240, the fluid flow rate and the fluid. The pressure also increased. Wherein, if the diameter of the flow holes 240 is less than 2 mm, the flow velocity and pressure of the fluid in the flow channel 230 are both 0, indicating that the fluid does not enter the flow channel 230. Next, if the diameter D1 of the orifices 240 is 6 mm, the flow velocity of the fluid in the flow tank 230 has decreased from 10 m/s to 5.12 m/s, and the fluid pressure in the flow tank 230 It also decreases from about 8.20 x 10 ⁴ Pa to 5.23 x 10 ⁴ Pa, which means that the fluid flow rate and fluid pressure in the flow channel 230 can be effectively reduced when the diameter D1 of the orifices 240 is 6 mm. However, if the diameter D1 of the orifices 240 is 10 mm, the fluid flow rate in the liquid flow tank 230 is equivalent to the fluid pressure and the inlet flow velocity and fluid pressure of the flow field, that is, the orifices 240 are too large without significant deceleration and The effect of decompression. It can be seen that the ratio of the diameter D1 of the flow holes 240 to the inner diameter D2 of the cylinder 200 is between about one tenth and one fifth, which can more effectively reduce the fluid flow rate in the liquid flow tank 230 and Fluid pressure.

Then, the flow field of the flow channel 230 formed under the diameter D1 of the different flow holes 240 is determined by the conductivity of the known fluid and the corresponding measurement voltage, and the known fluid is sensed by the sheet sensor 500. For the influence of the measured voltage value, please refer to FIG. 6 and FIG. 7. FIG. 6 is a line diagram showing the voltage sensed by the chip sensor of the flow hole of FIG. 7 is a line graph of the voltage measurement variation sensed by the chip sensor of FIG. 3 at different diameters.

For example, if the conductivity of the fluid is known to be 0.748 mS/cm, then the known fluid has a measured voltage of 296 millivolts at rest. However, if the fluid is located in the flow channel 230, the voltage value of the fluid sensed by the chip sensor 500 at different times will increase with the diameter D1 of the flow holes 240. A fluctuating state is exhibited, and the voltage measurement variation number also becomes larger as the diameter D1 of the flow holes 240 increases. In detail, as shown in FIGS. 6 and 7, it can be observed that when the diameter D1 of the flow holes 240 is less than 2 mm, since the flow velocity of the fluid in the flow channel 230 is 0, the variation of the voltage measurement is performed. Is 0. However, when the diameter D1 of the flow holes 240 is 10 mm, since the flow velocity of the fluid in the flow channel 230 approximates the inlet flow velocity of the flow field, the sheet sensor 500 is disturbed by the flow and pressure of the fluid, and The measured voltage will exhibit a fluctuating state at different times, and the voltage measurement has a variation of up to 206 millivolts. Therefore, it can be known that the ratio of the diameter D1 of the flow holes 240 to the inner diameter D2 of the cylindrical body 200 is between about one tenth and one fifth, in a state where the fluid flows in the liquid flow tank 230. Maintaining a lower measured voltage variation also has the effect of further reducing the fluid flow rate and fluid pressure within the flow cell 230.

Through the foregoing simulations and experiments, it can be judged that when the diameter D1 of the flow holes 240 is 6 mm, not only the fluid flow rate and the fluid pressure in the flow channel 230 can be effectively reduced, but also for the chip sensor. The measured variation of 500 is kept within an acceptable range. Next, the effect of the inner diameter D2 of the different cylinders 200 on the fluid flow rate and the fluid pressure in the liquid flow tank 230 is simulated under the condition that the diameter D1 of the flow holes 240 is set to 6 mm and the other conditions are constant. Please refer to FIG. 8 and FIG. 9. FIG. 8 is a flow chart of the average flow velocity of the flow channel formed by the cylinder of FIG. 2 under different inner diameters. Figure 9 is a flow field average pressure line diagram of the flow cell formed by the barrel of Figure 2 at different inner diameters.

As shown in Figs. 8 and 9, in the case where the inner diameter D2 of the cylinder 200 is 70 mm and 90 mm, the fluid flow rates in the liquid flow tank 230 are 10.53 m/s and 12.5 m/s, respectively. And the fluid pressures were 10.25 × 10 ⁴ Pa and 20 × 10 ⁴ Pa, respectively. It can be seen that as the inner diameter D2 of the cylinder 200 increases, the fluid flow rate and fluid pressure in the liquid flow tank 230 also increase. Wherein, when the inner diameter D2 of the cylinder 200 is 70 mm, the flow velocity of the liquid flow tank 230 has approached the inlet fluid flow velocity of the flow field, and even when the inner diameter D2 of the cylinder 200 is 90 mm, the liquid flow The flow rate of the tank 230 exceeds the inlet fluid flow rate of the flow field, so the measured variation under the inner diameter D2 of the cylinder 200 of 70 mm and 90 mm is 50 mm than the inner diameter D2 of the cylinder 200. The situation is even more increasing. In combination with the foregoing simulations and experiments, it can be verified that the ratio of the diameter D1 of the orifice 240 to the inner diameter D2 of the cylinder 200 is between about one tenth and one fifth, and the liquid flow tank 230 can be further The fluid flow rate and fluid pressure are reduced to obtain a smaller measurement variation, and the sensed value of the sheet sensor 500 is more correct.

Next, the relationship between the distance L1 between the L1 and the tube length L2 of the column portion 210 in the axial direction of the cylinder 200 is illustrated by simulation data, wherein the distance L1 between the second holes 240 refers to the center of the flow hole 240 to another The distance from the center of the first hole 240. Please refer to FIG. 10 and FIG. 11 first. FIG. 10 is a flow chart of the average flow velocity of the flow channel formed by the two adjacent orifices in the axial direction of the cylinder at different intervals. Figure 11 is a flow field average pressure line diagram of the flow channel formed by the two adjacent orifices in the axial direction of the cylinder of Figure 2 at different intervals.

The inner diameter D2 of the cylindrical body 200 is 50 mm, the tube length L2 of the cylindrical portion 210 is 100 mm, the diameter D1 of the flow holes 240 is 20 mm, the length L of the flow field is 300 mm, and the width W is 100 mm, height H is 100 mm, the flow velocity at the inlet is 10 m/s, and the viscosity of the fluid is 1 × 10 ^-3 Pa. S is a simulated condition, and the flow rate and pressure change under the different spacing L1 of the two adjacent orifices 240 in the axial direction of the cylinder 200 are observed.

As shown in Figs. 10 and 11, it can be seen that as the distance L1 between the two adjacent orifices 240 in the axial direction of the cylinder 200 increases, the fluid flow rate and fluid pressure in the liquid flow tank 230 gradually decrease. In detail, when the distance L1 between the axially adjacent second flow holes 240 of the cylinder 200 is 10 mm, the fluid flow rate in the liquid flow tank 230 is 11.32 meters/second without effect of slowing the inlet flow velocity of the flow field. . However, when the distance L1 between the two axially adjacent holes 240 of the cylinder 200 is 15 mm, the flow velocity of the fluid in the flow channel 230 is 7.53 meters/second, and the flow velocity of the flow field has a significant slowing effect. . Therefore, it can be seen from the simulation that the ratio of the distance between the L1 and the tube length L2 of the cylinder portion 210 between the axially adjacent tubular holes 240 of the cylinder 200 needs to be greater than one tenth, and the fluid in the liquid flow tank 230 can be further further. Flow rate and fluid pressure are reduced.

In the present embodiment, it can be known from the above simulation and experimental data that the ratio between the diameter D1 of the flow holes 240 and the inner diameter D2 of the cylindrical body 200 needs to be between one tenth and one fifth. The ratio between the distance L1 between the L1 and the tube length L2 of the cylindrical portion 210 of the axial direction of the cylindrical body 200 is greater than one tenth, which can further reduce the fluid velocity and fluid pressure in the liquid flow tank 230. The formation of a more stable and gentle flow field, so that the sheet sensor 500 not only improves the accuracy of the measurement and the stability of the value, but also avoids the sensing device 10 when measuring the properties and composition content of the fluid. destroyed.

In addition, in the foregoing simulations and experiments, the diameter D1 of each of the flow holes 240 is the same, but is not limited thereto. In other embodiments, the ratio between the diameter of the orifices and the inner diameter of the barrel may be between one tenth and one fifth, and the axial direction of the cylinder, as described in the foregoing simulations and experiments. The ratio of the distance between the adjacent two orifices to the length of the cylinder portion is required to be greater than one tenth, and the orifices may be formed by a combination of diameters of different sizes.

In addition, in the present embodiment, the cylindrical body 200 is screwed through the external thread structure 2222 of the assembly ring 222 and the internal thread 120 of the flow tube 100, so that the cylinder 200 is well fixed to the flow tube 100, so that the cylinder 200 does not The displacement due to the fluid pressure in the flow tube 100 is reduced, and the measurement accuracy and stability of the sheet sensor 500 are lowered. Furthermore, the manner in which the tubular body 200 and the flow tube 100 are screwed together is not intended to limit the present invention. Please refer to FIG. 12, which is an exploded view of a sensing device according to a second embodiment of the present invention.

In the sensing device 10' of the embodiment, the cylinder 200' surrounds a liquid flow tank 230', and the cylinder 200' has a plurality of flow holes 240', and the flow holes 240' are connected to the liquid flow tank 230'. . In detail, the cylinder 200' includes a cylindrical portion 210' and an assembled portion 220' which are axially connected. The cylindrical portion 210' surrounds the flow channel 230', and these flow holes 240' are respectively located at the cylindrical portion 210'. The assembly seat portion 220' includes a body 221' and an assembly ring 222'. The assembly ring 222' protrudes from the seat body 221', and the column portion 210' is coupled to one end of the assembly ring 222' away from the seat body 221'. The assembly ring 222' has an outer wall surface 2221' and a first snap structure 2222', and the first snap structure 2222' is located on the outer wall surface 2221'. The flow tube 100' has a second snap structure 120', and the first snap structure 2222' is coupled to the second snap structure 120' to secure the barrel 200' to the flow tube 100'. In this embodiment, the number of the first fastening structure 2222' and the second fastening structure 120' are two, but not limited thereto.

According to the sensing device disclosed in the above embodiments, when the chip sensor needs to simultaneously measure a plurality of properties of the fluid, it is only necessary to add a sensing property corresponding to the different properties of the measuring fluid on the chip sensor. Since the weight and volume of the integrated chip sensor are not significantly increased, it can be easily placed in the flow tube.

In addition, by placing the sheet-like sensing wafer in the liquid flow tank of the cylinder, when the fluid in the flow tube enters the liquid flow tank from the flow holes, the structure of the cylindrical body and the flow of the cylindrical portion of the cylindrical body The design of the hole can slow down the flow rate and pressure of the fluid flowing in the flow tube, so that the fluid flow rate and pressure after the fluid enters the liquid flow channel through the flow holes become smaller, thereby forming a stable flow field, thereby avoiding the sheet feeling. In addition to the destruction of the detector, it is also possible to improve the accuracy and numerical stability of the properties and compositional contents of the sheet-shaped sensing wafer.

Furthermore, the ratio between the diameter of the orifices and the inner diameter of the cylinder can be adjusted between one tenth and one fifth, and the distance between the two adjacent orifices in the axial direction of the cylinder The ratio of the length of the column portion is greater than one tenth to further reduce the fluid velocity and fluid pressure in the flow channel to form a more stable and gentle flow field, so that the sheet sensor measures the properties of the fluid and When the content of the component is increased, the accuracy of the measurement and the stability of the numerical value are further improved, and the sensing device is prevented from being destroyed.

In addition, in some embodiments, the fixing manner between the cylinder and the flow tube is respectively screwed or clamped between the buckle structures, so that the cylinder is well fixed to the flow tube, so that the cylinder does not Due to the displacement of the fluid pressure in the flow tube, the measurement accuracy and stability of the sheet sensor can be maintained.

Although the present invention has been described above in terms of the preferred embodiments thereof, it is not intended to limit the present invention, and it is intended that those skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. The scope of the new patent protection shall be subject to the definition of the scope of the patent application attached to this specification.

10, 10'‧‧‧ Sensing device

11‧‧‧Wire

100, 100’ ‧ ‧ flow tube

110‧‧‧liquid flow path

120‧‧‧ internal thread

120’‧‧‧Second buckle structure

200, 200’‧‧‧ cylinder

210, 210’‧‧‧ Column Department

211‧‧ ‧ guiding groove

220, 220’‧‧‧Assembly

221, 221’‧‧‧ body

222, 222’‧‧‧ Assembly ring

2221, 2221'‧‧‧ outer wall

2222‧‧‧ external thread structure

2222'‧‧‧First buckle structure

2223‧‧‧Setting trough

230, 230'‧‧‧ flow cell

240, 240’‧‧‧ orifice

300‧‧‧Seal ring

400‧‧‧First electrical connector

500‧‧‧Slice sensor

510‧‧‧Second electrical connector

D1‧‧‧ diameter

D2‧‧‧Down

L2‧‧‧Headmaster

L1‧‧‧ spacing

L‧‧‧ length

W‧‧‧Width

H‧‧‧ Height

FIG. 1 is a perspective view of a sensing device according to a first embodiment of the present invention. Figure 2 is an exploded view of Figure 1. Figure 3 is a cross-sectional view of Figure 1. Figure 4 is a flow chart of the average flow velocity of the flow channel formed by the orifices of Figure 3 at different diameters. Figure 5 is a flow field average pressure line diagram of the flow channel formed by the orifice of Figure 3 at different diameters. 6 is a line diagram of the voltage sensed by the chip sensor of FIG. 3 as a function of time at different diameters. 7 is a line graph of the voltage measurement variation sensed by the chip sensor of FIG. 3 at different diameters. Figure 8 is a flow chart of the average flow velocity of the flow channel formed by the cylinder of Figure 2 under different inner diameters. Figure 9 is a flow field average pressure line diagram of the flow cell formed by the barrel of Figure 2 at different inner diameters. Figure 10 is a flow chart of the flow field average flow velocity of the flow channel formed by the two adjacent orifices in the axial direction of the cylinder of Figure 3 at different intervals. Figure 11 is a flow field average pressure line diagram of the flow channel formed by the two adjacent orifices in the axial direction of the cylinder of Figure 3 at different intervals. Figure 12 is an exploded view of a sensing device in accordance with a second embodiment of the present invention.

Claims (14)

An embedded sensing module comprises: a cylinder surrounding a liquid flow tank, the cylinder having a plurality of flow holes, the flow holes being connected to the liquid flow groove; and at least one piece sensing The device is embedded in the liquid flow tank. The embedded sensing module of claim 1, wherein a ratio of a diameter of each of the orifices to an inner diameter of the cylinder is between one tenth and one fifth. The embedded sensing module of claim 1, wherein the cylinder comprises a cylindrical portion connected in the axial direction and an assembly seat, the cylindrical portion surrounding the liquid flow channel, the flow holes Located in the column body. The embedded sensing module of claim 3, wherein a ratio of a distance between the two adjacent holes in the axial direction of the cylindrical body and a length of the tube of the cylindrical portion is greater than one tenth. The embedded sensing module of claim 3, further comprising a sealing ring, the assembling seat portion comprising a body and an assembly ring, the assembly ring protruding from the seat body, the column body portion being connected The assembly ring has an outer wall surface, a set of slots and an externally threaded structure, and the sleeve groove and the external thread structure are located on the outer wall surface, and the sleeve is grooved. Located between the externally threaded structure and the seat body, the sealing ring is sleeved in the sleeve. The embedded sensing module of claim 3, further comprising a first electrical connector, the at least one sensor having a second electrical connector, the first electrical connector being disposed on the The second electrical connector is assembled into the seat and electrically connected to the at least one piece of the sensor. The embedded sensing module of claim 3, wherein the column portion has two guiding grooves, wherein the two guiding grooves are located in the liquid flow channel, and the two guiding grooves are respectively away from the cylindrical portion One end of the assembly seat extends toward the assembly seat, and opposite ends of the at least one sensor are respectively embedded in the liquid flow groove corresponding to the two guide grooves. The embedded sensing module of claim 3, wherein the assembly base comprises a body and an assembly ring, the assembly ring protrudes from the base, and the cylindrical portion is connected to the assembly ring away from One end of the base body, the assembly ring has an outer wall surface and a snap structure, and the snap structure is located on the outer wall surface. The embedded sensing module of claim 1, wherein the flow holes have different diameters. A sensing device comprising: a first-stage tube surrounding a liquid flow path; a barrel surrounding a liquid flow channel, the barrel having a plurality of flow holes, the flow holes being in communication with the liquid flow channel; At least one piece of sensor is embedded in the liquid flow channel; wherein the barrel is detachably inserted into the flow tube, so that the at least one piece of sensor communicates with the liquid flow path through the flow holes . The sensing device of claim 10, wherein the cylinder comprises a cylindrical portion connected in the axial direction and an assembly portion, the cylindrical portion surrounding the liquid flow channel, wherein the flow holes are respectively located a cylindrical portion, the assembly portion includes a body and an assembly ring, the assembly ring protrudes from the base body, the column portion is connected to an end of the assembly ring away from the base body, the assembly ring has an outer wall surface and An externally threaded structure is located on the outer wall surface, the flow tube having an internal thread coupled to the internal thread to secure the barrel to the flow tube. The sensing device of claim 10, wherein the cylinder comprises a cylindrical portion connected in the axial direction and an assembly portion, the cylindrical portion surrounding the liquid flow channel, wherein the flow holes are respectively located a cylindrical portion, the assembly portion includes a body and an assembly ring, the assembly ring protrudes from the base body, the column portion is connected to an end of the assembly ring away from the base body, the assembly ring has an outer wall surface and At least one first fastening structure, the at least one first fastening structure is located on the outer wall surface, the flow tube has at least one second fastening structure, the at least one first fastening structure and the at least one second fastening structure Bonding to secure the barrel to the flow tube. The sensing device of claim 10, wherein a ratio of a diameter of each of the orifices to an inner diameter of the cylinder is between one tenth and one fifth. The sensing device of claim 10, wherein the cylinder comprises a cylindrical portion connected in the axial direction and an assembly portion, the cylindrical portion surrounding the liquid flow channel, wherein the flow holes are respectively located The ratio of the distance between the two axial holes adjacent to the tubular body and the length of the tube of the cylindrical portion is greater than one tenth.