A flow meter

Abstract

The present application relates to the technical field of instrument and meter for measuring fluid flow through a pipeline, and particularly relates to a flowmeter, comprising a base, a laminar flow structure, a sensor component and a sealing component; the laminar flow structure has a laminar flow air channel and at least two groups of longitudinal holes; the sensor component is used for detecting corresponding pressure and pressure difference at the holes, and comprises independently distributed pressure detection ends and integrally arranged pressure difference detection ends; the sealing component has at least two balance chambers in communication with the holes, for corresponding distribution of the pressure detection ends and the pressure difference detection ends; the coverage of the balance chambers extends from the holes to the circumferential side, and narrows the distribution distance of a pair of pressure difference detection ends. By arranging the sealing component, the sealing effect is achieved, and meanwhile, the balance chambers formed on the sealing component make it possible to simultaneously distribute the pressure detection ends with a long distance and the pressure difference detection ends with a constant short distance, so that the effect of higher and more stable detection precision is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of instrument and meter technology for measuring fluid flow through a pipeline, and in particular to a flow meter. BACKGROUND

[0002] Since the laminar flow meter is an instrument and meter based on differential pressure principle to monitor fluid flow, it is suitable for laminar flow state, so it can be considered that the laminar flow state is a necessary condition for such flow meter, and from the perspective of fluid mechanics, it is suitable for flow under low Reynolds number. Therefore, the laminar flow meter is used to measure the flow of small flow and high viscosity fluid. One of its advantages is that the differential pressure △P delivered by the flow meter is proportional to the volume flow Qv, and the structure is simple.

[0003] In the process of flow measurement, the differential pressure in the fluid flow process needs to be obtained in real time. The existing technology adopts the following ways to measure the differential pressure and the disadvantages are as follows:

[0004] a. The differential pressure is measured by using a differential pressure sensor. The traditional differential pressure sensor has two interfaces with a constant distance. The distance between the two interfaces is too close, the data obtained is small, and if the data is amplified, the error will also be large, which may cause low measurement accuracy and poor stability.

[0005] b. A plurality of pressure sensors are used to measure pressure, and the differential pressure is calculated. In this case, abnormal conditions cannot be judged, which may cause the problem of low structural reliability.

[0006] Therefore, the present application develops a flow meter to solve the problems in the prior art. SUMMARY

[0007] The purpose of the present application is to provide a flow meter to solve the problems of low precision, poor stability and low reliability of the laminar flow meter in the prior art.

[0008] The technical scheme of the present application is a flow meter, comprising:

[0009] a base, the base is designed in two parts and has assembly surfaces abutting each other, and a receiving cavity formed after assembly;

[0010] a laminar flow structure arranged in the receiving cavity; the laminar flow structure has a laminar flow passage and at least two groups of holes penetrating in the longitudinal direction;

[0011] a sensor member for detecting the corresponding pressure and differential pressure at the holes; the sensor member includes independently distributed pressure detection ends and integrally arranged differential pressure detection ends;

[0012] A sealing member is embedded at the inner ring of the assembly surface, and has at least two balance chambers in communication with the hole body inside, for corresponding distribution of the pressure detection end and the differential pressure detection end; the covering surface of the balance chamber extends from the hole body to the circumferential side, and narrows the distribution distance of a pair of differential pressure detection ends.

[0013] Preferably, the distance between the corresponding pressure detection ends in the two balance chambers is smaller than the distance between a pair of differential pressure detection ends, and the feedback data of the differential pressure detection end and the difference between the feedback data of a pair of pressure detection ends are mutually verified.

[0014] Preferably, the hole body, pressure detection end, differential pressure detection end, and balance chamber are arranged in pairs and symmetrically distributed; the space volumes formed by a pair of balance chambers are equal.

[0015] Preferably, the pressure detection end is correspondingly provided with a pressure sensor, and the differential pressure detection end is correspondingly provided with a differential pressure sensor.

[0016] The distribution direction of a pair of differential pressure detection ends and the distribution direction of a pair of pressure detection ends form an included angle, which reduces the occupied space of the differential pressure sensor along the distribution direction of a pair of pressure detection ends.

[0017] Preferably, in the sealing member, the partition part for separating a pair of balance chambers is arranged obliquely along the distribution direction perpendicular to a pair of differential pressure detection ends, so that a pair of balance chambers are constructed in a rotational symmetry structure.

[0018] Preferably, the laminar flow structure comprises laminar flow sheets and flow guide sheets arranged in sequence, spaced apart, and stacked;

[0019] The laminar flow sheets are provided with notches at both ends along the gas flow direction, and the end faces form the hole body; the notches and hole bodies distributed on a plurality of laminar flow sheets are arranged in alignment;

[0020] The flow guide grooves are arranged on the end face of the flow guide sheet, each flow guide groove is arranged along the gas flow direction, and a plurality of flow guide grooves are arranged along the direction perpendicular to the gas flow direction; the two ends of the flow guide groove are respectively arranged corresponding to the notches, and the space formed between the flow guide groove and the laminar flow sheets arranged above and below is constructed as the laminar flow channel.

[0021] Preferably, at the notches, the two ends of the flow guide grooves arranged in alignment above and below are respectively constructed as laminar flow inlet buffer cavities and laminar flow outlet buffer cavities; the laminar flow inlet buffer cavities and / or the laminar flow outlet buffer cavities are provided with filter assemblies.

[0022] Preferably, a laminar flow pressing plate is further arranged between the laminar flow structure and the sealing member, and a flow guide hole is formed in the laminar flow pressing plate, which communicates the hole body and the balance chamber.

[0023] Preferably, the base of the split design comprises a fixedly connected upper base and lower base;

[0024] The lower base is formed with a communicating air inlet, a receiving cavity and an air outlet;

[0025] The upper base is installed with the sensor member;

[0026] The lower end surface of the upper base and the upper end surface of the lower base form the assembly surface; the sealing member is pressed at the inner circle of the assembly surface between the upper base and the lower base.

[0027] Preferably, a shell is further connected to the base, the shell is used for packaging the sensor member, and a control module electrically connected to the sensor member is installed in the shell, and a connection terminal is installed at the outer wall.

[0028] Compared with the prior art, the advantages of the present application are:

[0029] (1) By setting the sealing member, the balance chamber formed thereon makes it possible to simultaneously distribute the pressure detection end at a long distance and the pressure difference detection end at a constant short distance, achieving higher and more stable detection precision; and the data feedback between the two can be used for mutual verification, with strong reliability.

[0030] (2) The distribution of the pair of hole bodies at a long distance, the setting of the pair of pressure sensors at a long distance, the increase of the data difference, and the setting of the balance chamber to shorten the distance between the two points at the same pressure of the pair of hole bodies, make it possible to install the pressure difference sensor, achieving the integrated setting of the pressure sensor and the pressure difference sensor.

[0031] (3) The sealing member and the laminar flow structure cooperate with each other, making the structures closely connected layer by layer, achieving the smooth flow of fluid along the laminar flow passage, and also enabling the fluid to flow along the hole body and the flow guide hole to the balance chamber, achieving real-time detection of pressure and pressure difference. BRIEF DESCRIPTION OF DRAWINGS

[0032] The present application will be further described below in conjunction with the drawings and embodiments:

[0033] Figure 1 It is a sectional view of the flow meter of the present application;

[0034] Figure 2 It is an exploded sectional view of the base and the sealing member of the present application;

[0035] Figure 3 It is a top view of the laminar flow structure of the present application;

[0036] Figure 4 A top view of the laminar flow sheet according to the present application;

[0037] Figure 5 A top view of the flow guide sheet according to the present application;

[0038] Figure 6 A schematic view of the laminar flow structure according to the present application;

[0039] Figure 7 A partial exploded view of the laminar flow structure according to the present application;

[0040] Figure 8 A sectional view of the laminar flow structure according to the present application;

[0041] Figure 9 An enlarged view of A in the laminar flow structure according to the present application; Figure 8

[0042] Figure 10 A sectional view of the upper base, sensor member and sealing member according to the present application;

[0043] Figure 11 A bottom view of the sealing member mounted on the upper base according to the present application;

[0044] Figure 12 A schematic view of the sealing member according to the present application in one embodiment;

[0045] Figure 13 A schematic view of the sealing member according to the present application in another embodiment.

[0046] 1. a base;

[0047] 11. an upper base, 12. a lower base, 13. an air inlet, 14. an air outlet, 15. an assembly surface, 16. a receiving cavity, 161. a stepped surface, 17. a housing, 18. a control module, 19. a connection terminal;

[0048] 2. a laminar flow structure;

[0049] 20. a laminar flow pressing plate, 201. a flow guide hole;

[0050] 21. a laminar flow sheet, 211. a hole body, 212. a notch;

[0051] 22. a flow guide sheet, 221. a flow guide groove, 222. a laminar flow air duct;

[0052] 23. a laminar flow air inlet buffer cavity, 24. a laminar flow air outlet buffer cavity;

[0053] 3. a sensor member;

[0054] ​31. Pressure sensor; 310. Pressure detection area; 311. Pressure detection end;

[0055] 32. Differential pressure sensor; 320. Differential pressure detection area; 321. Differential pressure detection end;

[0056] 4. Sealing components;

[0057] 41. Balance chamber; 42. Divider. Detailed Implementation

[0058] The present invention will be further described in detail below with reference to specific embodiments:

[0059] like Figure 1 As shown, a flow meter includes a base 1, a laminar flow structure 2, a sensor component 3, and a sealing component 4.

[0060] The base 1 is designed in two parts, with mating surfaces 15 that abut against each other, and a receiving cavity 16 formed after assembly.

[0061] In one implementation, such as Figure 2 As shown, the split-design base 1 includes an upper base 11 and a lower base 12 that are fixedly connected. The lower base 12 has a communicating air inlet 13, a receiving cavity 16 and an air outlet 14. The air inlet 13 and the air outlet 14 are located on the side wall of the lower base 12. The receiving cavity 16 is located on the upper end face of the lower base 12, and a stepped surface 161 is formed on the top periphery of the receiving cavity 16. The upper base 11 is fixed to the lower base 12. In the assembled state, the part of the lower end face of the upper base 11 that contacts the upper end face of the lower base 12 forms an assembly surface 15.

[0062] In other embodiments, the base 1 may also be composed of two or more separate structures, but the sealing of the assembly must be considered during the assembly process.

[0063] like Figure 1 , Figure 3 As shown, the laminar flow structure 2 is disposed in the accommodating cavity 16, including laminar flow plates 21 and flow guide plates 22 arranged in sequence at intervals and stacked.

[0064] Regarding laminar flow plate 21, as Figure 4 As shown, the laminar flow plate 21 has notches 212 at both ends along the gas flow direction, and at least two holes 211 are formed on the end face; the notches 212 and holes 211 distributed on the multiple laminar flow plates 21 are respectively aligned.

[0065] Regarding the guide vane 22, such as Figure 5As shown, several guide grooves 221 are distributed on the end face of the guide vane 22. Each guide groove 221 is arranged along the gas flow direction, and multiple guide grooves 221 are distributed perpendicular to the gas flow direction. The aligned holes 211 on the laminar flow vane 21 are connected to the guide grooves 221.

[0066] Combination Figure 6-9 As shown, in the stacked state of laminar flow plate 21 and guide plate 22, the two ends of guide groove 221 are respectively set with notches 212. At the notches 212, the two ends of the guide groove 221, which are arranged vertically and vertically, are respectively constructed as laminar flow inlet buffer chamber 23 and laminar flow outlet buffer chamber 24. The laminar flow inlet buffer chamber 23 is connected to the air inlet 13, and the laminar flow outlet buffer chamber 24 is connected to the air outlet 14. In order to reduce the contamination of the laminar flow structure 2 by external impurities, filter components can also be set in both the laminar flow inlet buffer chamber 23 and / or the laminar flow outlet buffer chamber 24. Figure 9 As shown, the space formed between the guide channel 221 and the upper and lower laminar flow plates 21 is constructed as a laminar flow air passage 222. After the gas flows in from the laminar flow inlet buffer chamber 23, it flows through the laminar flow air passage 222 and flows out from the laminar flow outlet buffer chamber 24. In summary, the entire laminar flow structure 2 is designed with a symmetrical structure for the gas flow passage from inlet to outlet.

[0067] Since the laminar flow structure 2 is located within the accommodating cavity 16, in the installation scenario, such as Figure 1 As shown, a laminar flow pressure plate 20 is also provided at the upper end of the laminar flow structure 2. The laminar flow pressure plate 20 has the same number of guide holes 201 as the number of holes 211 on each laminar flow plate 21. The guide holes 201 are aligned with the holes 211 on the laminar flow plate 21. Taking the direction shown in the figure as an example, the guide holes 201 and the holes 211 are distributed on the same longitudinal axis.

[0068] like Figure 10 As shown, sensor component 3 is installed inside upper base 11. In one embodiment, sensor component 3 is used to detect the pressure and differential pressure corresponding to the orifice 211. Sensor component 3 includes independently distributed pressure detection ends 311 and integrated differential pressure detection ends 321. Pressure sensor 31 is correspondingly provided on pressure detection ends 311, and differential pressure sensor 321 is correspondingly provided on differential pressure sensor 32. In terms of structural design, each pressure sensor 31 has one interface, which is defined as pressure detection end 311, and different pressure sensors 31 can be distributed arbitrarily; while each differential pressure sensor 32 has two interfaces, which are defined as differential pressure detection ends 321, and the distance between the two interfaces in differential pressure sensor 32 is constant.

[0069] In the application scene, a pressure sensor 31 needs to be arranged near each hole body 211, and the pressure difference between the hole bodies 211 can be obtained through the data difference of the pressure sensor 31. Therefore, in order to ensure the accuracy and stability of the pressure difference data, the distance between the hole bodies 211 cannot be too close, and when the distance between the hole bodies 211 is too far, the pressure difference sensor 32 with a constant interface distance cannot be arranged and installed. Therefore, the sealing member 4 is introduced in the present application, and a balance chamber 41 communicating with the hole body 211 is arranged in the sealing member 4. The coverage of the balance chamber 41 extends from the hole body 211 to the side, which narrows the distribution distance of a pair of pressure difference detection ends 321, that is, the arrangement of the balance chamber 41 makes it possible to integrally install the pressure difference sensor 32 and the pressure sensor 31.

[0070] Specifically, regarding the sealing member 4, as shown in Figure 1 , Figure 10 , the sealing member 4 is arranged between the upper base 11 and the lower base 12 corresponding to the inner circle of the assembly surface 15; the upper end face is arranged to abut the lower end face of the upper base 11, and the lower end face is arranged to abut the upper end face of the laminar flow plate 20, and the outer edge is supported at the stepped surface 161. As shown in Figure 11 , Figure 12 , the sealing member 4 has at least two balance chambers 41 communicating with the hole body 211, and the number of balance chambers 41 is the same as the number of hole bodies 211 on each laminar flow sheet 21, and the adjacent balance chambers 41 have a partition 42.

[0071] In an embodiment, as shown in Figure 11 , two balance chambers 41 are arranged, and the space volumes are equal. The number of hole bodies 211 and the number of flow guide holes 201 on each laminar flow sheet 21 corresponding to the balance chambers 41 are both two. In this embodiment, the two balance chambers 41 are the same in shape and size, which is beneficial to the consistency, stability and accuracy of pressure detection. Since the coverage of the balance chamber 41 extends from the hole body 211 to the side, the distance between a pair of hole bodies 211 is set as S, and the distance between a pair of balance chambers 41 must be less than the distance S. In the present application, as shown in Figure 12 , taking the area shown by the sealing member 4 as an example, the area close to the hole body 211 is defined as the pressure detection area 310, and the area on both sides of the partition 42 is defined as the pressure difference detection area 320. The pressure sensor 31 is installed corresponding to the pressure detection area 310, and the pressure difference sensor 32 is installed corresponding to the pressure difference detection area 320, and the distance between the pressure detection ends 311 corresponding to the two balance chambers 41 is less than the distance between a pair of pressure difference detection ends 321.

[0072] Therefore, in the embodiment, by arranging the sealing member 4, the balance chambers 41 formed thereon make it possible to simultaneously achieve the distribution of the pressure detection ends 311 at a long distance and the distribution of the differential pressure detection ends 321 at a constant short distance while playing a sealing role, achieving the effect of higher and more stable detection accuracy. Moreover, the combination of the sealing member 4 and the laminar flow structure 2 makes the flow rate pressure more stable, and the symmetrical flow channels and the balance chambers 41 of equal volume are beneficial to the consistency, stability, and accuracy of the pressure detection of the sensor member 3.

[0073] Since the pressure in each balance chamber 41 is theoretically equal, the difference between the data detected by the pair of pressure sensors 31 should be theoretically the same as the feedback data of the differential pressure sensor 32. In the present application, based on the arrangement of the pressure sensor 31 and the differential pressure sensor 32, the data between the two can be checked with each other. When the difference between the data detected by the pair of pressure sensors 31 deviates from the threshold range of the feedback data of the differential pressure sensor 32, an alarm feedback can be given, solving the problem of poor structural reliability in the prior art.

[0074] In other embodiments, the spatial volumes of the balance chambers 41 can also be unequal, as long as the space is large enough.

[0075] As a further discussion, regarding the differential pressure sensor 32, it has two interfaces. In an embodiment, as shown in Figure 11 , the distribution directions of the pair of differential pressure detection ends 321 and the distribution directions of the pair of pressure detection ends 311 form an included angle, which can reduce the occupied space of the differential pressure sensor 32 along the distribution direction of the pair of pressure detection ends 311. Further, as shown in Figure 12 , the partition part 42 in the sealing member 4 for separating the pair of balance chambers 41 is arranged in a diagonal direction perpendicular to the distribution direction of the pair of differential pressure detection ends 321, at this time, the pair of balance chambers 41 is constructed in a rotational symmetry structure.

[0076] In other embodiments, when the distribution directions of the pair of differential pressure detection ends 321 and the distribution directions of the pair of pressure detection ends 311 are parallel or arranged on the same straight line, the partition part 42 can also be arranged in the manner shown in Figure 13 .

[0077] As a flow meter, since the sensor member 3 is arranged, a control module 18 is necessarily provided, and therefore the base 1 is further connected with a shell 17, the shell 17 is used for packaging the sensor member 3, and the control module 18 electrically connected with the sensor member 3 is installed in the shell 17, and a connection terminal 19 is installed at the outer wall.

[0078] Based on the above structure, the working principle of the present application is mainly as follows:

[0079] Referring to Figure 6As shown, the gas flows in from the gas inlet 13, reaches the laminar flow inlet buffer cavity 23, then enters each laminar flow channel 222, and finally reaches the laminar flow outlet buffer cavity 24 before being discharged from the gas outlet 14. Due to the communication of the hole body 211, the flow guide hole 201 and the balance chamber 41, the gas also reaches the balance chamber 41. The air pressure in the balance chamber 41 corresponds to the air pressure at the hole body 211. According to the principle of detecting flow by pressure difference, when the flow of the medium is greater, the pressure difference generated is greater, so the size of the fluid flow can be measured by measuring the pressure difference.

[0080] The above embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. It is obvious for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or basic characteristics of the present application, therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-limiting, the scope of the present application is defined by the appended claims rather than the above description, therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application.

Claims

1. A flow meter, characterized in that, include: The base (1) is designed in two parts and has a mating surface (15) that abuts each other, and a receiving cavity (16) formed after assembly. A laminar flow structure (2) is disposed within the accommodating cavity (16); the laminar flow structure (2) has a laminar flow air passage and at least two sets of longitudinally penetrating holes (211). The sensor component (3) is used to detect the pressure and differential pressure at the orifice (211); the sensor component (3) includes independently distributed pressure detection ends (311) and integrated differential pressure detection ends (321). A sealing member (4) is fitted into the inner ring of the mounting surface (15) and has at least two balancing chambers (41) communicating with the orifice (211) for the pressure detection end (311) and the differential pressure detection end (321) to be distributed accordingly; the covering surface of the balancing chamber (41) extends from the orifice (211) to the periphery, bringing the distribution distance of the pair of differential pressure detection ends (321) closer; The distance between the pressure detection ends (311) correspondingly distributed in the two balance chambers (41) is less than the distance between a pair of differential pressure detection ends (321), and the feedback data of the differential pressure detection end (321) is mutually verified with the difference between the feedback data of the pair of pressure detection ends (311).

2. The flow meter according to claim 1, characterized in that: The orifice (211), pressure detection end (311), differential pressure detection end (321), and balance chamber (41) are all arranged in pairs and symmetrically distributed; the spatial volume formed by a pair of balance chambers (41) is equal.

3. A flow meter according to claim 2, characterized in that: The pressure detection end (311) is provided with a pressure sensor (31), and the differential pressure detection end (321) is provided with a differential pressure sensor (32). The distribution direction of the pair of differential pressure detection terminals (321) forms an angle with the distribution direction of the pair of pressure detection terminals (311), thereby reducing the space occupied by the differential pressure sensor (32) along the distribution direction of the pair of pressure detection terminals (311).

4. A flow meter according to claim 3, characterized in that: In the sealing member (4), the partition (42) used to separate the pair of balance chambers (41) is obliquely arranged along the distribution direction perpendicular to the pair of differential pressure detection ends (321), thereby making the pair of balance chambers (41) have a rotationally symmetrical structure.

5. A flow meter according to claim 1, characterized in that: The laminar flow structure (2) includes laminar flow plates (21) and flow guide plates (22) arranged sequentially at intervals and stacked. The laminar flow plate (21) has notches (212) at both ends along the gas flow direction, and the end face forms the hole (211); the notches (212) and holes (211) distributed on the multiple laminar flow plates (21) are respectively aligned; The guide vane (22) has a plurality of guide grooves (221) distributed on its end face. Each guide groove (221) is arranged along the gas flow direction, and the plurality of guide grooves (221) are arranged perpendicular to the gas flow direction. The two ends of the guide groove (221) are respectively arranged corresponding to the notch (212), and the space formed between the guide groove (221) and the laminar flow vanes (21) arranged above and below is constructed as the laminar flow channel (222).

6. A flow meter according to claim 5, characterized in that: At the notch (212), the two ends of the guide groove (221) arranged vertically are respectively constructed as a laminar flow inlet buffer chamber (23) and a laminar flow outlet buffer chamber (24); a filter assembly is provided in both the laminar flow inlet buffer chamber (23) and / or the laminar flow outlet buffer chamber (24).

7. A flow meter according to claim 6, characterized in that: A laminar flow pressure plate (20) is also provided between the laminar flow structure (2) and the sealing member (4). The laminar flow pressure plate (20) has a flow guide hole (201) that connects the hole body (211) with the balance chamber (41).

8. A flow meter according to claim 1, characterized in that: The base (1) with a split design includes an upper base (11) and a lower base (12) that are fixedly connected. The lower base (12) has a connected air inlet (13), a receiving cavity (16) and an air outlet (14). The sensor component (3) is installed inside the upper base (11); The lower end face of the upper base (11) and the upper end face of the lower base (12) form the assembly surface (15); the sealing member (4) is pressed between the upper base (11) and the lower base (12) at the inner ring of the assembly surface (15).

9. A flow meter according to any one of claims 1-8, characterized in that: The base (1) is also connected to a housing (17), which is used to encapsulate the sensor component (3). A control module (18) electrically connected to the sensor component (3) is installed inside the housing (17), and a connection terminal (19) is installed on the outer wall.

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