Laminar flow assembly module and flow meter

Abstract

The utility model relates to a laminar flow assembly module and a flow meter comprising the laminar flow assembly module. The laminar flow assembly module includes a sleeve and a shaft. The sleeve includes a cylindrical body and at least one protrusion protruding radially inward from an inner peripheral surface of the body and extending in an axial direction to a downstream end portion of the body. The shaft is configured to be rotatable relative to the sleeve and includes a first section received within the sleeve, the first section being provided with a boss protruding radially outward from an outer peripheral surface of the first section and extending in a circumferential direction. A laminar flow channel through which fluid passes is formed between adjacent circumferential end faces of at least one projection of the sleeve and between an inner circumferential surface of the body of the sleeve and an outer circumferential surface of the first section of the shaft. At least one projection is disposed on a downstream side of the boss in abutment with the boss such that when the shaft rotates relative to the sleeve, the boss at least partially shields or exposes an inlet of the laminar flow channel to change an effective flow area of the laminar flow channel, thereby adjusting a flow resistance of the laminar flow channel.

Description

Technical Field

[0001] The utility model relates to the field of fluid measuring devices, in particular to a laminar flow component module with adjustable flow resistance and a flow meter comprising the laminar flow component module. Background Art

[0002] The contents of this section merely provide background information related to the present invention and may not constitute prior art.

[0003] Some flow meters, especially mass flow meters, are equipped with laminar flow components that make the fluid flow in a laminar manner. Ideally, the pressure difference before and after the fluid passes through the laminar flow component is linearly related to the flow rate of the fluid, so the flow rate can be measured by measuring the pressure difference. In practical applications, in order to make the pressure difference and the flow rate have as high a linear correlation as possible, laminar flow components with different flow resistances are usually required for different ranges, which causes inconvenience to the measurement or calibration process, and replacing different laminar flow components may lead to inconsistent performance of the flow meter under different range conditions. Utility Model Content

[0004] One object of the present disclosure is to provide a laminar flow component with adjustable flow resistance to adapt to different ranges of a flow meter and improve the measurement accuracy under different flow conditions. Another object of the present disclosure is to provide a modular laminar flow component to reduce the number of parts of the flow meter and simplify the structure of the flow meter.

[0005] One aspect of the present disclosure provides a laminar flow component module for use in a flow meter, the laminar flow component module comprising a sleeve and a shaft. The sleeve comprises a cylindrical body and at least one protrusion protruding radially inward from the inner circumferential surface of the body and extending in an axial direction to the downstream end of the body. The shaft is configured to be rotatable relative to the sleeve and comprises a first section received in the sleeve, the first section being provided with a boss protruding radially outward from the outer circumferential surface of the first section and extending in a circumferential direction. A laminar flow channel for fluid to pass through is formed between adjacent circumferential end faces of at least one protrusion of the sleeve and between the inner circumferential surface of the body of the sleeve and the outer circumferential surface of the first section of the shaft. At least one protrusion abuts the boss and is arranged on the downstream side of the boss, so that when the shaft rotates relative to the sleeve, the boss at least partially blocks or exposes the inlet of the laminar flow channel to change the effective flow area of ​​the laminar flow channel.

[0006] In some embodiments, the shaft further comprises a second section connected to the first section and arranged outside the sleeve, a series of indexing holes spaced apart in the circumferential direction are provided on the outer circumferential surface of the second section, and the indexing holes are used to receive locking pins to lock the shaft at a predetermined angular position.

[0007] In some embodiments, the shaft further comprises markings indicating an initial position of the shaft.

[0008] In some embodiments, the sleeve includes a plurality of protrusions spaced apart in a circumferential direction to define a plurality of independent laminar flow channels, and a rotation angle of the shaft is limited such that at least one of the plurality of laminar flow channels is not affected by the boss.

[0009] In some embodiments, a first annular protrusion, a second annular protrusion, and a third annular protrusion are provided on the outer circumferential surface of the body of the sleeve, which protrude radially outward and are spaced apart in the axial direction. The third annular protrusion is provided between the first annular protrusion and the second annular protrusion, so that a first bypass chamber connected to the inlet fluid of the laminar flow channel is formed between the first annular protrusion and the third annular protrusion, and a second bypass chamber connected to the outlet fluid of the laminar flow channel is formed between the second annular protrusion and the third annular protrusion.

[0010] In some embodiments, at least one protrusion of the sleeve has an arcuate or sawtooth shaped cross section.

[0011] In some embodiments, the shaft further includes one or more positioning holes for receiving a tool to drive the shaft to rotate.

[0012] In some embodiments, the circumferential width of the boss is greater than or equal to the circumferential width of a laminar flow channel.

[0013] Another aspect of the present disclosure provides a flow meter, which includes a housing, a laminar flow component module according to the above aspect, and a differential pressure sensor, wherein the laminar flow component module is received in the housing, and the differential pressure sensor is configured to measure the pressure difference between the fluid pressure at the inlet and the fluid pressure at the outlet of the laminar flow channel of the laminar flow component module. The flow meter is configured to convert the measured differential pressure data into flow data.

[0014] In some embodiments, the sleeve of the laminar flow assembly module is interference fit in the housing.

[0015] According to the laminar flow component module disclosed in the present invention, the effective flow area of ​​the laminar flow channel defined between the shaft and the sleeve is changed by the relative rotation of the shaft relative to the sleeve, thereby changing the flow resistance of the laminar flow channel to adapt to different flow conditions, effectively improving the measurement accuracy under various flow conditions. In particular, when a graduated hole is provided on the shaft, the shaft can be quickly and accurately adjusted to a predetermined flow gear. In addition, the present disclosure provides a laminar flow component module with a simple structure and adjustable flow resistance, which can be easily adapted to various flow meters, reduces the number of parts of the flow meter, simplifies the structure of the flow meter, and improves the reliability and consistency of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following will describe the embodiments of the present invention by way of example only with reference to the accompanying drawings. In the accompanying drawings, the same features or components are represented by the same reference numerals, and the drawings are not necessarily drawn to scale. In the accompanying drawings:

[0017] Figure 1 shows a cross-sectional view of a flow meter according to one embodiment of the present disclosure, taken along a longitudinal plane passing through an axis;

[0018] Figure 2 and Figure 3 They are shown respectively Figure 1 A perspective view of an axis in a laminar flow assembly module of a flow meter and a cross-sectional view taken along a longitudinal plane passing through the axis;

[0019] Figure 4 and Figure 5 They are shown respectively Figure 1 A perspective view of a sleeve in a laminar flow assembly module of a flow meter and a cross-sectional view taken along a longitudinal plane passing through the axis;

[0020] Figure 6 Shown along Figure 5 A cross-sectional view of the sleeve taken along line AA in FIG.

[0021] Figures 7a to 7d Shows the lower edge of different flow levels Figure 5 A cross-sectional view of the laminar flow assembly module taken along line AA in FIG.

[0022] Figure 8 shows a cross-sectional view of a sleeve according to another embodiment of the present disclosure, taken along a longitudinal plane passing through the axis;

[0023] Fig. 9 Shown along Figure 8 A cross-sectional view of the sleeve taken along line A'-A' in FIG. DETAILED DESCRIPTION

[0024] The following description is merely exemplary in nature and is not intended to limit the present invention, its application and use. It should be understood that in all of the accompanying drawings, similar reference numerals indicate the same or similar parts and features. The various drawings only schematically represent the concepts and principles of the embodiments of the present invention, and do not necessarily show the specific dimensions and proportions of the various embodiments of the present invention. Specific parts in specific drawings may be exaggerated to illustrate the relevant details or structures of the embodiments of the present invention.

[0025] In the description of the embodiments of the present invention, the directional terms used in relation to directions such as "upper" and "lower" are described by referring to the upper and lower positions of the views shown in the accompanying drawings. In practical applications, the positional relationships of "upper" and "lower" used herein can be defined according to actual conditions, and these relationships can be reversed.

[0026] Figure 1 FIG. 2 shows a cross-sectional view of a flow meter 1 according to an embodiment of the present disclosure, taken along a longitudinal plane passing through the axis. Figure 1 As shown, the flow meter 1 includes a housing 10, which defines a fluid inlet 110 and a fluid outlet 120 that can be communicated with a fluid pipeline. In this article, the side close to the fluid inlet 110 is called upstream, and the side close to the fluid outlet 120 is called downstream. The flow meter 1 also includes a laminar flow component module 20 and a differential pressure sensor 30. The laminar flow component module 20 is arranged between the fluid inlet 110 and the fluid outlet 120 in the housing 10 and defines a laminar flow channel 210 that allows the fluid to flow downstream in a laminar state. The differential pressure sensor 30 is configured to measure the pressure difference between the fluid pressure at the inlet of the laminar flow channel 210 and the fluid pressure at the outlet. Under the ideal state of laminar flow of the fluid, the pressure difference is proportional to the fluid flow through the laminar flow channel 210, so the flow meter 1 can convert the measured differential pressure data into flow data.

[0027] The laminar flow assembly module 20 includes a shaft 220 and a sleeve 230 . Figure 2 and Figure 3 A perspective view and a cross-sectional view of the shaft 220 taken along a longitudinal plane passing through the axis are shown respectively. Figures 4 to 6 The three-dimensional view of the sleeve 230, the cross-sectional view taken along the longitudinal plane passing through the axis, and the cross-sectional view taken along the longitudinal plane passing through the axis are respectively shown. Figure 5 A cross-sectional view taken along line AA in FIG.

[0028] The shaft 220 may be formed of, for example, a metal material or any other suitable material by machining. Figures 1 to 3As shown, the shaft 220 may include a first section 221 and a second section 222 connected to each other, and the sleeve 230 includes a body 231 that is generally hollow and cylindrical. The outer diameter of the first section 221 of the shaft 220 is smaller than the inner diameter of the body 231 of the sleeve 230, and the outer diameter of the second section 222 is larger than the outer diameter of the first section 221 and larger than the inner diameter of the body 231 of the sleeve 230, so that in an assembled state, the first section 221 is received in the sleeve 230, and the second section 222 is located outside the sleeve 230. A portion of the shaft 220 is hollow to allow fluid from the fluid inlet 110 to pass through. In particular, the shaft 220 includes a central hole 223 extending along the axis, and the central hole 223 extends from one end of the second section 222 along the axis through a portion of the first section 221. At the position where the central hole 223 is provided in the first section 221, the first section 221 further includes a through hole 224 which is connected to the central hole 223 and extends radially outward to penetrate the first section 221, so that the fluid from the fluid inlet 110 can flow through the central hole 223 and the through hole 224 to the laminar flow channel 210 formed between the shaft 220 and the sleeve 230. Figure 2 and Figure 3 As shown, in this embodiment, four through holes 224 are evenly distributed along the circumferential direction of the first section 221. Downstream of the through hole 224, at least one boss 226 is provided, which protrudes from the outer circumferential surface 225 of the first section 221 and extends in the circumferential direction. In the assembled state, the boss 226 slides and engages the inner circumferential surface 232 of the body 231 of the sleeve 230 to prevent the passage of fluid. In this embodiment, two bosses 226 spaced apart and opposite to each other are provided in the circumferential direction. In other embodiments, the number and position of the through hole 224 and the boss 226 can be arranged in any suitable manner according to actual needs. In addition, in other embodiments, instead of the central hole 223 and the through hole 224, any other suitable fluid path can also be provided to introduce the fluid from the fluid inlet 110 into the laminar flow channel 210 between the shaft 220 and the sleeve 230.

[0029] The shaft 220 is configured to be rotatable relative to the sleeve 230. A series of indexing holes 227 spaced apart in the circumferential direction may be provided on the outer circumferential surface of the second section 222 of the shaft 220 for receiving the locking pin 40 to lock the shaft 220 at a predetermined angular position. Figure 1 As shown, the locking pin 40 may be configured as a spring ball plunger, for example, which includes a ball 410 that is biased by a spring and engages with the outer peripheral surface of the second section 222 of the shaft 220. When the shaft 220 is rotated so that the ball 410 falls into a graduated hole, the shaft 220 is locked in the corresponding angular position. Continuing to rotate the shaft 220 can cause the ball 410 to overcome the spring force and leave the graduated hole, and roll along the outer peripheral surface of the second section 222 of the shaft 220 to the next graduated hole, so as to lock the shaft 220 in the next predetermined angular position. In this embodiment, as shown in FIG. Figure 2 As best shown, the first to fourth indexing holes 227a to 227d are provided, and the interval between each two adjacent indexing holes is about 15°. In other embodiments, the number and interval angle of the indexing holes 227 can be set in any suitable manner according to actual needs. The shaft 220 may also include a mark 228 indicating the initial position of the shaft 220. The mark 228 may be set, for example, as a groove or pattern on the axial end surface of the second section 222, such as a scale line. When the mark 228 is aligned with the corresponding mark on the housing 10, the user can know that the shaft 220 is in the initial position. The mark 228 may be set to align with the axis of one indexing hole (such as the first indexing hole 227a located at the outermost side) in the series of indexing holes 227. The shaft 220 may also include one or more positioning holes 229, and the user may extend the tool into the positioning hole 229 to drive the shaft 220 to rotate. The positioning hole 229 may be set, for example, on the axial end surface or outer peripheral surface of the second section 222 of the shaft 220.

[0030] The sleeve 230 may be formed, for example, by an injection molding process. Figure 1 and Figures 4 to 6As shown, the body 231 of the sleeve 230 is provided with at least one protrusion 233 protruding radially inward from the inner circumferential surface 232 of the body 231, and each protrusion 233 extends along the axial direction of the body 231 to the downstream end of the body 231. In the assembled state, the protrusion 233 is slidably engaged with the outer circumferential surface 225 of the first section 221 of the shaft 220 to prevent the passage of fluid, and the space formed between the opposite circumferential end surfaces of two adjacent protrusions 233 spaced apart in the circumferential direction (in the case of only a single protrusion 233, it is between the two opposite circumferential end surfaces of the single protrusion 233) and between the inner circumferential surface 232 of the body 231 of the sleeve 230 and the outer circumferential surface 225 of the first section 221 of the shaft 220 constitutes a laminar flow channel 210 allowing the passage of fluid. The width of each protrusion 233 extending in the circumferential direction, the circumferential gap width between adjacent protrusions 233 and the number of protrusions 233 can be set according to the width and number of the desired laminar flow channel 210. In the present embodiment, the sleeve 230 is provided with four protrusions 233 evenly spaced in the circumferential direction, thereby defining four independent laminar flow channels 210 therebetween. Each protrusion 233 and each laminar flow channel 210 each have an arc cross section of about 45°. In the assembled state, the protrusion 233 of the sleeve 230 is arranged on the downstream side of the boss 226 against the boss 226 of the shaft 220. By rotating the shaft 220, the position of the boss 226 of the shaft 220 relative to the protrusion 233 of the sleeve 230 can be changed, thereby the effective flow area of ​​the laminar flow channel 210 can be changed by at least partially shielding or exposing the inlet of the laminar flow channel 210 through the boss 226 of the shaft 220. The circumferential width of each boss 226 may be set to be greater than or equal to the circumferential width of a laminar flow channel 210, so that the boss 226 can completely close the entrance of the laminar flow channel 210. In this embodiment, each boss 226 has an arc cross section equal to or slightly greater than 45°.

[0031] like Figure 4 , Figure 5 As shown, three annular protrusions that protrude radially outward and are spaced apart in the axial direction may be provided on the outer peripheral surface 234 of the body 231 of the sleeve 230. In the illustrated embodiment, the first annular protrusion 235a is provided at the upstream end of the body 231, the second annular protrusion 235b is provided at the opposite downstream end of the body 231, and the third annular protrusion 235c is provided between the first annular protrusion 235a and the second annular protrusion 235b. Figure 1As shown, in the assembled state, the sleeve 230 can be fixed in the housing 10 by interference fit, so that a first bypass chamber 236a communicating with the first port 310 of the differential pressure sensor 30 is formed between the first annular protrusion 235a and the third annular protrusion 235c, and a second bypass chamber 236b communicating with the second port 320 of the differential pressure sensor 30 is formed between the second annular protrusion 235b and the third annular protrusion 235c, and the first bypass chamber 236a and the second bypass chamber 236b are separated by the third annular protrusion 235c. A through hole 237 that radially penetrates the body 231 of the sleeve 230 is provided near the first annular protrusion 233a, so that the fluid communicates the inlet of the laminar flow channel 210 with the first bypass chamber 236a. Similarly, a through hole 238 that radially penetrates the body 231 of the sleeve 230 is provided near the second annular protrusion 233b, so that the fluid communicates the outlet of the laminar flow channel 210 with the second bypass chamber 236b. Thus, the inlet of the laminar flow channel 210 is communicated with the first port 310 of the differential pressure sensor 30, and the outlet of the laminar flow channel 210 is communicated with the second port 320 of the differential pressure sensor 30, so that the differential pressure sensor 30 can measure the pressure difference between the inlet and the outlet of the laminar flow channel 210. In this embodiment, four through holes 237 and four through holes 238 are evenly distributed along the circumferential direction of the body 231. In other embodiments, the number and position of the through holes 237 and 238 can be set in any suitable manner according to actual needs.

[0032] The working principle of the flow meter 1 and its laminar flow component module 20 is described in detail below. Figure 1As shown, when the flow meter 1 is used for flow measurement, the fluid flows from the fluid inlet 110 into the central hole 223 of the shaft 220, and flows into the laminar flow channel 210 defined between the first section 221 of the shaft 220 and the sleeve 230 (the portion not blocked by the boss 226 of the shaft 220) through the through hole 224 on the first section 221 of the shaft 220. The fluid will generate a certain pressure drop when flowing through the laminar flow channel 210. Ideally, the value of the pressure drop is proportional to the flow rate of the fluid. A small portion of the fluid near the inlet of the laminar flow channel 210 is introduced into the first port 310 of the differential pressure sensor 30 via the through hole 237 on the sleeve 230 and the first bypass chamber 236a outside the sleeve 230, and a small portion of the fluid near the outlet of the laminar flow channel 210 is introduced into the second port 320 of the differential pressure sensor 30 via the through hole 238 on the sleeve 230 and the second bypass chamber 236b outside the sleeve 230, thereby, the differential pressure sensor 30 can measure the pressure difference between the first port 310 and the second port 320, that is, the pressure drop between the inlet and the outlet of the laminar flow channel 210. In order to make the pressure drop between the inlet and the outlet of the laminar flow channel 210 and the fluid flow rate through the laminar flow channel 210 have a linear relationship close to the ideal situation under different flow conditions, according to the flow range to be measured, the user can change the flow resistance of the laminar flow component module 20 by rotating the shaft 220. Specifically, as the shaft 220 rotates, the boss 226 on the shaft 220 rotates circumferentially relative to the protrusion 233 while abutting against the protrusion 233 of the sleeve 230, thereby at least partially shielding or exposing the laminar flow channel 210 to change the effective flow area of ​​the laminar flow channel 210, thereby changing the flow resistance of the laminar flow component module 20. In this embodiment, the shaft 220 can be conveniently locked in a number of predetermined flow gears through a series of indexing holes 227 on the shaft 220 and a locking pin 40 matched with the indexing holes 227.

[0033] Figures 7a to 7d Shows the lower edge of different flow levels Figure 5 2 is a cross-sectional view of the laminar flow assembly module 20 taken along line AA in FIG. In the present embodiment, the shaft 220 and the sleeve 230 together define first to fourth laminar flow channels 210a to 210d that are independent of each other. Figure 7a The initial position of the shaft 220 corresponding to the first dividing hole 227a in a series of dividing holes 227 is shown, wherein the two bosses 226 of the shaft 220 are aligned with the first laminar flow channel 210a and the second laminar flow channel 210b arranged opposite to each other, thereby completely blocking the first laminar flow channel 210a and the second laminar flow channel 210b, so that the fluid can only flow through the third laminar flow channel 210c and the fourth laminar flow channel 210d that are not blocked by the bosses 226. Figure 7bThe second position of the shaft 220 is shown in which the shaft 220 is rotated counterclockwise by about 15° from the initial position (i.e., rotated until the locking pin 40 is engaged with the second indexing hole 227b), wherein the two bosses 226 of the shaft 220 respectively expose a portion of the first laminar channel 210a and the second laminar channel 210b, thereby allowing a portion of the fluid to flow through the exposed portions of the first laminar channel 210a and the second laminar channel 210b. Figure 7c The third position is shown in which the shaft 220 is rotated counterclockwise about 15° from the second position (i.e., rotated until the locking pin 40 is engaged with the third indexing hole 227c), wherein the two bosses 226 of the shaft 220 expose a larger portion of the first laminar flow channel 210a and the second laminar flow channel 210b respectively. Figure 7d The fourth position of the shaft 220 is shown in which the shaft 220 is rotated counterclockwise by about 15° from the third position (i.e., rotated to the point where the locking pin 40 is matched with the fourth indexing hole 227d), wherein the two bosses 226 of the shaft 220 are roughly aligned with the two protrusions 233 of the sleeve 230, respectively, so that the first laminar flow channel 210a and the second laminar flow channel 210b are basically completely exposed. During the period when the shaft 220 rotates from the initial position to the fourth position, the effective flow area of ​​the first laminar flow channel 210a and the second laminar flow channel 210b changes with the position of the boss 226, and the flow resistance also changes accordingly, while the third laminar flow channel 210c and the fourth laminar flow channel 210d are never affected by the boss 226. In other words, the rotation angle of the shaft 220 can be limited so that at least one of the multiple laminar flow channels is not affected by the boss 226.

[0034] The above adjustment method is non-restrictive. In other embodiments, the number, circumferential width, spacing angle of the boss 226 of the shaft 220, the protrusion 233 of the sleeve 230 and the fluid channels 210 therebetween, as well as the number and spacing angle of the indexing holes 227 can be set in any suitable manner, as long as the rotation of the shaft 220 relative to the sleeve 230 can cause the boss 226 to change the effective flow area of ​​at least one fluid channel 210. For example, the circumferential width of each boss 226 of the shaft 220 can be set to be greater than the circumferential width of each protrusion 233 of the sleeve 230, so that each boss 226 can simultaneously block a portion of two adjacent fluid channels. For another example, the shaft 220 may include four bosses 226 aligned with four fluid channels, respectively. In this way, the effective flow area of ​​each fluid channel can be adjusted.

[0035] Figure 8 2 shows a cross-sectional view of a sleeve 230' according to another embodiment of the present disclosure, taken along a longitudinal plane passing through the axis. Fig. 9 Shown along Figure 82 is a cross-sectional view of a sleeve 230' taken along the line A'-A' in FIG. 2 , which can replace the sleeve 230 in the aforementioned embodiment. Compared with the sleeve 230, the sleeve 230' is provided with one or more sawtooth protrusions 239' between each two adjacent arcuate protrusions 233'. The height of the sawtooth protrusion 239' can be the same as the height of the arcuate protrusion 233', that is, in the assembled state, the arcuate protrusion 233' and the sawtooth protrusion 239' can be slidably engaged with the outer peripheral surface 225 of the first section 221 of the shaft 220 to prevent the passage of the fluid. Thus, an elongated laminar flow channel 210' extending in the axial direction to the downstream end of the sleeve 230' is formed between the relative circumferential end surfaces of the adjacent arcuate protrusions 233' and the sawtooth protrusions 239'. This is conducive to more accurately achieving the adjustment of the flow resistance and maintaining the laminar flow state of the fluid. For example, the angle between each two adjacent elongated laminar flow channels 210' may correspond to the angle between each two adjacent indexing holes on the shaft, so that each rotation of the shaft 220 by a predetermined gear position may just expose or block one or more elongated laminar flow channels 210'. Other aspects of the sleeve 230' may be the same or similar to the sleeve 230 in the aforementioned embodiment, and will not be described in detail here.

[0036] A laminar flow assembly module according to the present disclosure may also include any other suitable variations.

[0037] For example, although a series of predetermined gears for easy adjustment are provided through the indexing hole 227 on the shaft 220 in the above embodiment, the utility model is not limited thereto. For example, the indexing hole 227 may not be provided, but the shaft 220 may be locked in any desired position by pressing the locking pin 40 against the shaft 220, that is, the laminar flow assembly module according to the utility model can achieve stepless adjustment of the flow resistance.

[0038] For another example, in the above-mentioned embodiment, the second section 222 of the shaft 220 is arranged on the outside of the sleeve 230 to facilitate the user to rotate and lock the shaft 220 through the second section 222, but in other embodiments, the second section 222 of the shaft 220 can also be constructed with an outer diameter equal to or slightly smaller than the inner diameter of the body 231 of the sleeve 230, so that the second section 222 is also received in the sleeve 230.

[0039] For example, in the above-mentioned embodiment, the boss 226 of the shaft 220 slides and engages the inner circumferential surface 232 of the body 231 of the sleeve 230, and the protrusion 233 of the sleeve 230 slides and engages the outer circumferential surface 225 of the first section 221 of the shaft 220, thereby preventing the fluid from passing through. However, in other embodiments, a small gap allowing a small amount of fluid to pass through may also be formed between the boss 226 of the shaft 220 and the inner circumferential surface 232 of the body 231 of the sleeve 230, and between the protrusion 233 of the sleeve 230 and the outer circumferential surface 225 of the first section 221 of the shaft 220.

[0040] The utility model provides a laminar flow component module that can be adapted to various flow meters, which can adjust the flow resistance of the laminar flow channel by relative rotation between the shaft and the sleeve, thereby selecting a suitable gear according to the flow range to be measured, thereby effectively improving the measurement accuracy under different flow conditions. In addition, the laminar flow component module and the flow meter according to the utility model have a simple structure, a small number of parts, and are easy to process and assemble. Since the laminar flow channel is suitable for having a smaller flow area to ensure the laminar flow of the fluid therein, the laminar flow component module according to the utility model is particularly suitable for a flow meter with a smaller range of about 0 to 10L.

[0041] Here, exemplary embodiments of the laminar flow assembly module and the flow meter containing the laminar flow assembly according to the utility model have been described in detail, but it should be understood that the utility model is not limited to the specific embodiments described and shown in detail above. Without departing from the main purpose and scope of the utility model, those skilled in the art can make various modifications and variations to the utility model. All these modifications and variations fall within the scope of the utility model. Moreover, all the components described herein can be replaced by other technically equivalent components.

Claims

1. A laminar flow component module, the laminar flow component module is used in a flow meter, characterized in that: The laminar flow assembly module comprises: a sleeve including a cylindrical body and at least one protrusion protruding radially inwardly from an inner peripheral surface of the body and extending in an axial direction to a downstream end of the body; and a shaft configured to be rotatable relative to the sleeve and comprising a first section received in the sleeve, the first section being provided with a boss protruding radially outward from an outer peripheral surface of the first section and extending in a circumferential direction, wherein a laminar flow channel for fluid to pass through is formed between adjacent circumferential end surfaces of the at least one protrusion of the sleeve and between the inner circumferential surface of the body of the sleeve and the outer circumferential surface of the first section of the shaft, The at least one protrusion is arranged abutting against the boss on a downstream side of the boss, so that when the shaft rotates relative to the sleeve, the boss at least partially blocks or exposes the inlet of the laminar flow channel to change the effective flow area of ​​the laminar flow channel.

2. The laminar flow assembly module according to claim 1, characterized in that: The shaft further comprises a second section connected to the first section and arranged outside the sleeve, a series of indexing holes spaced apart in a circumferential direction are arranged on an outer circumferential surface of the second section, and the indexing holes are used to receive locking pins to lock the shaft at a predetermined angular position.

3. The laminar flow component module according to claim 1 or 2, characterized in that: The shaft also includes markings indicating an initial position of the shaft.

4. The laminar flow component module according to claim 1 or 2, characterized in that: The sleeve includes a plurality of the protrusions spaced apart in a circumferential direction to define a plurality of independent laminar flow channels, and a rotation angle of the shaft is limited so that at least one of the plurality of laminar flow channels is not affected by the boss.

5. The laminar flow component module according to claim 1 or 2, characterized in that: A first annular protrusion, a second annular protrusion and a third annular protrusion are provided on the outer peripheral surface of the body of the sleeve, which protrude radially outward and are spaced apart in the axial direction. The third annular protrusion is provided between the first annular protrusion and the second annular protrusion, so that a first bypass chamber connected to the inlet fluid of the laminar flow channel is formed between the first annular protrusion and the third annular protrusion, and a second bypass chamber connected to the outlet fluid of the laminar flow channel is formed between the second annular protrusion and the third annular protrusion.

6. The laminar flow component module according to claim 1 or 2, characterized in that: The at least one protrusion of the sleeve has an arc-shaped or sawtooth-shaped cross-section.

7. The laminar flow component module according to claim 1 or 2, characterized in that: The shaft also includes one or more positioning holes for receiving a tool to drive the shaft to rotate.

8. The laminar flow component module according to claim 1 or 2, characterized in that: The circumferential width of the boss is greater than or equal to the circumferential width of one of the laminar flow channels.

9. A flow meter, characterized in that: The flow meter comprises: case; The laminar flow component module according to any one of claims 1 to 8, the laminar flow component module being received in the housing; and a differential pressure sensor configured to measure a pressure difference between a fluid pressure at an inlet and a fluid pressure at an outlet of the laminar flow channel of the laminar flow assembly module, The flow meter is configured to convert the measured differential pressure data into flow data.

10. The flow meter according to claim 9, characterized in that The sleeve of the laminar flow assembly module is interference fit in the housing.

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