Mass flow meter and mass flow controller with same

Abstract

A mass flow meter comprises a pipeline body and a sensor. The pipeline body is provided with a main flow channel, a first sensor branch flow channel, a second sensor branch flow channel and a containing chamber; and two ends of the first sensor branch flow channel and the second sensor branch flow channel are respectively communicated with the main flow channel and the accommodating chamber. The sensor is arranged in the containing chamber and connected to the first sensor branch flow channel and the second sensor branch flow channel, so that a part of fluid enters the sensor through the first sensor branch flow channel, and the flow of the fluid is measured. The pipeline body is further provided with a pressure chamber which is communicated with the containing chamber and the main flow channel, so that a part of fluid can enter the pressure chamber, and pressure inside and outside the sensor is consistent. In addition, the utility model further provides a mass flow controller with the mass flow meter. According to the utility model, the probability that the sensor is damaged by high-pressure fluid can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of detecting and controlling the flow of fluids, such as liquids and gases, and particularly to a mass flow meter capable of reducing the probability of a sensor being damaged by pressure and a mass flow controller having the mass flow meter. Background Art

[0002] A mass flow controller (MFC) is a fluid flow measurement and control device that takes temperature and pressure into consideration. In recent years, it has been widely used to measure and control the flow of compressible fluids such as gas and liquid. Generally speaking, the main components of a mass flow controller include a mass flow meter (MFM), a control valve, and a controller. The mass flow meter has a pipeline and a sensor. The pipeline has the functions of filtering, stabilizing flow, and combining the sensor and the control valve; the sensor is used to monitor the flow of the fluid passing through the pipeline and transmit a flow signal to the controller; the controller controls the control valve according to the flow signal to adjust the flow of the fluid flowing out of the pipeline.

[0003] The most important component of the mass flow controller mentioned above is obviously the mass flow meter. The two most common mass flow meters on the market are thermal mass flow meters and Coriolis mass flow meters. Thermal mass flow meters use the thermal diffusion effect of gas for measurement, while Coriolis flow meters use the Coriolis principle for measurement.

[0004] In practice, it is found that because the pipeline and the sensor are made of different materials (usually the pipeline is metal and the sensor is plastic), the sensor is often damaged by the high-pressure fluid in the pipeline body or leaks, causing the sensor to be unable to correctly sense the flow rate of the fluid. Utility Model Content

[0005] The utility model aims to provide a mass flow meter and a mass flow controller having the mass flow meter, which can reduce the probability of a sensor being damaged by a high-pressure fluid.

[0006] In order to achieve the above-mentioned purpose and effect, the utility model provides a mass flow meter including: a pipeline body, having a main channel, a first sensor branch channel, a second sensor branch channel and a chamber; wherein the two ends of the first sensor branch channel and the second sensor branch channel are respectively connected to the main channel and the chamber; a filter is arranged in the main channel; and a sensor, having an inlet air nozzle and an outlet air nozzle; the sensor is installed in the chamber, so that the inlet air nozzle is connected to the first sensor branch channel, and the outlet air nozzle is connected to the second sensor branch channel, whereby a part of the fluid passing through the main channel can enter the sensor via the first sensor branch channel, and then return to the main channel from the second sensor branch channel, so as to measure the flow rate of the fluid. Wherein, the pipeline body is further provided with a pressure chamber, which is respectively connected to the chamber and the main channel, so that a part of the fluid passing through the main channel can enter the pressure chamber, resulting in the same pressure inside and outside the sensor.

[0007] The utility model further provides a mass flow controller, comprising: a pipeline body, having a main channel, a first sensor branch channel, a second sensor branch channel, a chamber, a post-valve main channel, a first valve branch channel and a second valve branch channel; wherein the two ends of the first sensor branch channel and the second sensor branch channel are respectively connected to the main channel and the chamber; one end of the first valve branch channel is connected to the main channel, and one end of the second valve branch channel is connected to the post-valve main channel; a filter is arranged in the main channel; a sensor, having an inlet air nozzle and an outlet air nozzle; the sensor is installed in the chamber so that the inlet air nozzle is connected to the first sensor branch channel A channel, the outlet air nozzle is connected to the second sensor branch channel; thereby, a part of the fluid passing through the main channel can enter the sensor through the first sensor branch channel, and then return to the main channel through the second sensor branch channel, so as to detect the flow rate of the fluid; and a control valve, having a valve inlet and a valve outlet, the control valve is arranged on the pipeline body, so that the valve inlet is connected to the first valve branch channel, and the valve outlet is connected to the second valve branch channel; thereby, the fluid of the main channel enters the control valve from the first valve branch channel, and then enters the main channel after the valve through the second valve branch channel; the control valve adjusts the flow rate of the fluid flowing out of the valve outlet according to the flow detected by the sensor. Among them, the pipeline body is further provided with a pressure chamber and an air channel, the pressure chamber is connected to the chamber, and the air channel is respectively connected to the pressure chamber and the main channel, so that a part of the fluid passing through the main channel will enter the pressure chamber through the air channel, resulting in the same pressure inside and outside the sensor.

[0008] In one embodiment, the volume of the chamber is larger than that of the sensor, so that a space is generated between the sensor and the side wall of the chamber, and the space forms the pressure chamber.

[0009] In one embodiment, the diameter of the first sensor branch channel is larger than the inlet nozzle of the sensor, so that a space is generated between the inlet nozzle and the side wall of the first sensor branch channel, and the space forms the air channel.

[0010] In one embodiment, an O-ring is disposed at the outlet nozzle of the sensor to make the pressure chamber and the second sensor branch channel airtight.

[0011] In one embodiment, a cover is further included. When the sensor is installed in the chamber, the cover closes the chamber.

[0012] According to the purpose and effect of the present invention, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a three-dimensional diagram of the first preferred embodiment of the utility model, showing the appearance of the mass flow meter.

[0014] Figure 2 It is an exploded sectional view of the first preferred embodiment of the utility model.

[0015] Figure 3 It is a combined sectional view of the first preferred embodiment of the utility model.

[0016] Figure 4 yes Figure 3 A partial enlarged view of .

[0017] Figure 5 It is a cross-sectional view of a second preferred embodiment of the utility model, showing a mass flow controller having the mass flow meter. DETAILED DESCRIPTION

[0018] See also Figures 1 to 4 As shown, a mass flow meter 1 disclosed in the first preferred embodiment of the present invention includes: a pipe body 10 and a sensor 12 .

[0019] The pipeline body 10 is made of metal and is provided with a main channel 14, a first sensor branch channel 16, a second sensor branch channel 18 and a chamber 20. The main channel 14 has a channel inlet 22 at one end of the pipeline body 10 and a channel outlet 24 at the other end. The two ends of the first sensor branch channel 16 and the second sensor branch channel 18 are respectively connected to the main channel 14 and the chamber 20, and the first sensor branch channel 16 is closer to the channel inlet 22 than the second sensor branch channel 18. A first joint 26 is connected to the channel inlet 22 to introduce a fluid into the main channel 14. A second joint 28 is connected to the channel outlet 24 to guide the fluid in the main channel 14 out. A filter 30 is installed in the main channel 14 to filter the fluid. The filter 30 is provided with an airtight ring 32 , which abuts against the wall of the main channel 14 and is located between the first sensor branch channel 16 and the second sensor branch channel 18 , so that part of the fluid enters the first sensor branch channel 16 from the outside of the filter 30 .

[0020] One side of the chamber 20 is open on the outer surface of the pipe body 10. The sensor 12 is installed in the chamber 20, and then a cover 34 is fixed to the pipe body to close the chamber 20. The sensor 12 has an inlet nozzle 36 connected to the first sensor branch channel 16, and an outlet nozzle 38 connected to the second sensor branch channel 18.

[0021] Through the above combination, most of the fluid entering the main channel 14 from the first joint 26 will pass through the filter 30, and a small part of the fluid will enter the sensor 12 from the outside of the filter 30 through the first sensor branch channel 16, and then return to the main channel 14 through the second sensor branch channel 18. In this way, the sensor 12 can detect the flow rate, pressure, temperature, humidity, etc. of the fluid and generate a detection signal accordingly.

[0022] The main technical features of the utility model are: the pipeline body 10 is provided with a pressure chamber 40 and an air passage 42. The pressure chamber 40 is connected to the chamber 20, and the two ends of the passage 42 are respectively connected to the pressure chamber 40 and the main flow passage 14, so that a part of the fluid passing through the main flow passage 14 can enter the pressure chamber 40 through the air passage 42. In this way, the pressure inside and outside the sensor 12 can be roughly the same, so as to reduce the probability of the sensor 12 being damaged by the high-pressure fluid entering the sensor 12.

[0023] See also Figure 4As shown, in the first preferred embodiment, the volume of the chamber 20 is larger than the sensor 12, so when the sensor 12 is installed in the chamber 20, a space is generated between the sensor 12 and the side wall of the chamber 20, and this space forms the pressure chamber 40. In other words, the pressure chamber 40 is a part of the chamber 20, and this part is the space not occupied by the sensor 12. The diameter of the first sensor branch channel 16 is larger than the inlet nozzle 36 of the sensor 12, so that a space is generated between the inlet nozzle 36 and the side wall of the first sensor branch channel 16, and this space forms the air channel 42. Most of the fluid passing through the first sensor branch channel 16 enters the sensor 12 through the inlet nozzle 36, and a small part enters the pressure chamber 40 through the air channel 42, so that the pressure inside and outside the sensor 12 is constantly kept the same. In practice, only one O-ring 44 is provided on the outlet air nozzle 38 to make the pressure chamber 40 and the second sensor branch channel 18 airtight, while the inlet air nozzle 36 can achieve the above-mentioned effect without the O-ring.

[0024] See also Figure 5 As shown, the second preferred embodiment of the present invention provides a mass flow controller 2 , comprising the mass flow meter 1 disclosed in the first preferred embodiment and a control valve 46 .

[0025] As mentioned above, the mass flow meter 1 includes the pipeline body 10 and the sensor 12, wherein the pipeline body 10 has the main channel 14, the chamber 20, the first sensor branch channel 16 and the second sensor branch channel 18, the pressure chamber 40 and the air channel 42. The above component structures are the same as those mentioned above and are not repeated. The differences include: the pipeline body 10 is further provided with a post-valve main channel 48, a first valve branch channel 50 and a second valve branch channel 52. There is a partition wall 54 between the main channel 14 and the post-valve main channel 48 so that the two are not connected to each other. The first valve branch channel 50 is located on one side of the partition wall 54, and one end is connected to the main channel 14. The second valve branch channel 52 is located on the other side of the partition wall 54, and one end is connected to the post-valve main channel 48. In addition, the second joint 28 is changed to be connected to one end of the post-valve main channel 48. The control valve 46 has a valve inlet 56 and a valve outlet 58 . The control valve 46 is disposed on the pipeline body 10 , so that the valve inlet 56 is connected to the first valve branch channel 50 , and the valve outlet 58 is connected to the second valve branch channel 52 .

[0026] Through the above structure, the fluid entering the main channel 14 from the first connector 26 will first pass through the filter 30, then enter the control valve 46 from the first valve branch channel 50, then enter the post-valve main channel 48 from the second valve branch channel 52, and finally be discharged from the second connector 28. As mentioned above, a small portion of the fluid will enter the sensor 12 from the outside of the filter 30 through the first sensor branch channel 16, so that the sensor 12 detects the flow of the fluid, generates a detection signal based on it, and transmits it to a processor 60. The processor 60 controls the control valve 46 according to the detection signal to adjust the flow of the fluid discharged from the valve outlet 58 of the control valve 46, so that the fluid in the post-valve main channel 48 is adjusted to have a preset flow rate.

[0027] As mentioned above, the pipe body 10 is also provided with the pressure chamber 40 and the air channel 42, so that a part of the fluid in the main channel 14 enters the pressure chamber 40 through the air channel 42 to keep the pressure inside and outside the sensor 12 close, thereby reducing the probability of the sensor 12 being damaged by the high-pressure fluid.

[0028] The above are the preferred embodiments of the utility model and the technical principles used therein. For those skilled in the art, without departing from the spirit and scope of the utility model, any obvious changes such as equivalent transformation, simple replacement, etc. based on the technical solution of the utility model shall fall within the protection scope of the utility model.

Claims

1. A mass flow meter, characterized in that: Contains: A pipeline body having a main channel, a first sensor branch channel, a second sensor branch channel and a receiving chamber; wherein two ends of the first sensor branch channel and the second sensor branch channel are respectively connected to the main channel and the receiving chamber; a filter is disposed in the main channel; and a sensor having an inlet nozzle and an outlet nozzle; the sensor is installed in the chamber, the inlet nozzle is connected to the first sensor branch channel, and the outlet nozzle is connected to the second sensor branch channel, whereby a portion of the fluid passing through the main channel can enter the sensor via the first sensor branch channel and then return to the main channel via the second sensor branch channel, so as to measure the flow rate of the fluid; The pipeline body is further provided with a pressure chamber and an air channel, wherein the pressure chamber is connected to the containing chamber, and the air channel is respectively connected to the pressure chamber and the main channel, so that a part of the fluid passing through the main channel will enter the pressure chamber through the air channel, causing the pressure inside and outside the sensor to be consistent.

2. The mass flow meter according to claim 1, characterized in that The volume of the chamber is larger than that of the sensor, so that a space is generated between the sensor and the side wall of the chamber, and the space forms the pressure chamber.

3. The mass flow meter according to claim 1, characterized in that The diameter of the first sensor branch channel is larger than the inlet nozzle of the sensor, so that a space is generated between the inlet nozzle and the side wall of the first sensor branch channel, and the space forms the air channel.

4. The mass flow meter according to claim 2, characterized in that An O-ring is arranged at the outlet air nozzle of the sensor to make the pressure chamber and the second sensor branch channel airtight.

5. The mass flow meter according to claim 1, characterized in that The device further comprises a sealing cover, which seals the chamber after the sensor is installed in the chamber.

6. A mass flow controller, characterized in that: Contains: A pipeline body, comprising a main channel, a first sensor branch channel, a second sensor branch channel, a containing chamber, a post-valve main channel, a first valve branch channel and a second valve branch channel; wherein two ends of the first sensor branch channel and the second sensor branch channel are respectively connected to the main channel and the containing chamber; one end of the first valve branch channel is connected to the main channel, and one end of the second valve branch channel is connected to the post-valve main channel; a filter is arranged in the main channel; a sensor having an inlet nozzle and an outlet nozzle; the sensor is installed in the chamber, the inlet nozzle is connected to the first sensor branch channel, and the outlet nozzle is connected to the second sensor branch channel; thereby, a portion of the fluid passing through the main channel can enter the sensor through the first sensor branch channel and then return to the main channel through the second sensor branch channel, so as to detect the flow rate of the fluid; and a control valve having a valve inlet and a valve outlet, the control valve being arranged on the pipeline body so that the valve inlet is connected to the first valve branch flow channel, and the valve outlet is connected to the second valve branch flow channel; thereby, the fluid in the main flow channel enters the control valve from the first valve branch flow channel, and then enters the post-valve main flow channel from the second valve branch flow channel; the control valve adjusts the flow rate of the fluid flowing out of the valve outlet according to the flow rate detected by the sensor; The pipeline body is further provided with a pressure chamber and an air channel, wherein the pressure chamber is connected to the containing chamber, and the air channel is respectively connected to the pressure chamber and the main channel, so that a part of the fluid passing through the main channel will enter the pressure chamber through the air channel, causing the pressure inside and outside the sensor to be consistent.

7. The mass flow controller according to claim 6, characterized in that The volume of the chamber is larger than that of the sensor, so that a space is generated between the sensor and the side wall of the chamber, and the space forms the pressure chamber.

8. The mass flow controller according to claim 6, characterized in that The diameter of the first sensor branch channel is larger than the inlet nozzle of the sensor, so that a space is generated between the inlet nozzle and the side wall of the first sensor branch channel, and the space forms the air channel.

9. The mass flow controller according to claim 8, characterized in that An O-ring is arranged at the outlet air nozzle of the sensor to make the pressure chamber and the second sensor branch channel airtight.

10. The mass flow controller according to claim 6, characterized in that The device further comprises a sealing cover, which seals the chamber after the sensor is installed in the chamber.

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