Flow splitter, method of manufacturing a flow splitter, mass flow measuring device and control device

Abstract

The application provides a flow divider, a manufacturing method thereof, a mass flow measuring device and a mass flow control device. The flow divider comprises a cylindrical body, a plurality of flow spaces for fluid passing are formed in the cylindrical body and are distributed along the radial direction of the cylindrical body, each of the flow spaces is arranged along the circumferential direction of the cylindrical body, each of the flow spaces is formed between mutually parallel inner and outer circumferential wall surfaces, and the radial distance and effective flow area of the inner and outer circumferential wall surfaces are set to make the fluid flowing through the flow space in a laminar flow state. The scheme of the application can reduce the overall size on the basis of being applicable to large or super-large flow, thereby reducing the difficulty of production and manufacturing, debugging and calibration, installation, maintenance and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor manufacturing, in particular to a flow splitter and a manufacturing method thereof, a mass flow measuring device and a mass flow control device. BACKGROUND

[0002] In the field of semiconductor, many processes need to measure and control the flow of fluid, especially for the scene using a variety of corrosive, toxic gas, the accuracy of the full range of requirements are very high. For example, with the development of hydrogen fuel new energy technology, the measurement and control of flow is required to exceed 5000 slm (standard liter per minute, standard liters per minute).

[0003] At present, the mass flow meter (MFM) and mass flow controller (MFC) with flow up to 5000 slm or more to achieve large flow or super large flow, the flow splitter generally needs a large size mechanical structure, the mechanical size is too large, in addition to increasing the cost, more importantly, it will increase the difficulty of production, debugging, calibration and installation, maintenance, etc.

[0004] Therefore, how to provide a flow splitter, which can reduce the mechanical size, reduce the processing and installation difficulty on the basis of being suitable for large flow or super large flow, is a problem to be solved at present. SUMMARY

[0005] The present application aims to at least solve one of the technical problems existing in the prior art, and provides a flow splitter and a manufacturing method thereof, a mass flow measuring device and a mass flow control device, which can reduce the overall size on the basis of being suitable for large flow or super large flow, thereby reducing the difficulty of production, debugging, calibration and installation, maintenance, etc.

[0006] To achieve the purpose of the present application, a flow splitter is provided, comprising a cylindrical body, a plurality of flow spaces for fluid passing through are formed in the cylindrical body and are spaced apart along the radial direction of the cylindrical body, each of the flow spaces is arranged along the circumferential direction of the cylindrical body.

[0007] Each of the flow spaces is formed between mutually parallel inner and outer peripheral wall surfaces, and the radial distance and effective flow area of the inner and outer peripheral wall surfaces are arranged to make the fluid flowing through the flow space in a laminar flow state.

[0008] Optionally, the cylindrical body comprises a plurality of ring bodies coaxially and nested with each other, and the two surfaces of each adjacent two ring bodies opposite to each other are the inner and outer peripheral wall surfaces, respectively.

[0009] Optionally, a plurality of support members are arranged between each two adjacent ring bodies along the circumferential direction of the ring bodies; and the flow space is formed in the region between the inner circumferential wall and the outer circumferential wall corresponding to the interval between each two adjacent support members.

[0010] Optionally, the cylindrical body comprises a first spiral body wound by a first flat plate, and the inner circumferential wall and the outer circumferential wall are formed by the regions of the two spiral surfaces of the first spiral body opposite to each other.

[0011] Optionally, a plurality of support members are arranged between the two spiral surfaces of the first spiral body along the spiral direction; and the flow space is formed in the region between the inner circumferential wall and the outer circumferential wall corresponding to the interval between each two adjacent support members.

[0012] Optionally, the flow divider further comprises a second spiral body, and the first spiral body and the second spiral body are wound by the first flat plate and a second flat plate stacked with each other, wherein,

[0013] A plurality of hollow portions penetrating through the thickness of the second flat plate are arranged on the second flat plate, and the plurality of hollow portions are arranged along the length direction of the second flat plate; the interval part between each two adjacent hollow portions of the second flat plate forms the support member, and the hollow portion forms the flow space;

[0014] The first spiral body and the second spiral body form an inlet and an outlet at each end of the hollow portion along the axial direction of the cylindrical body, so as to allow fluid to flow into and out of the hollow portion.

[0015] Optionally, the first flat plate is located on the side of the second flat plate away from the winding central axis.

[0016] Optionally, the first flat plate comprises a main body part; the size of the hollow portion in the width direction of the second flat plate is greater than the width of the main body part, and the two edge regions of the hollow portion in the width direction of the second flat plate are located outside the two side edges of the main body part, so as to form the inlet or the outlet.

[0017] Optionally, the size of the plurality of hollow portions in the length direction of the second flat plate increases from the winding starting end to the winding ending end of the second flat plate.

[0018] Optionally, the winding starting end and the winding ending end of the second flat plate are respectively provided with a first connecting part and a second connecting part, the first flat plate comprises a main body part, a third connecting part and a fourth connecting part, the third connecting part and the fourth connecting part are respectively arranged at the two ends of the main body part in the length direction of the main body part, wherein the third connecting part is located at the winding starting end of the first flat plate, and the fourth connecting part is located at the winding ending end of the first flat plate.

[0019] The first connecting part and the third connecting part are stacked and fixedly connected with each other; and the second connecting part and the fourth connecting part are stacked and fixedly connected with each other.

[0020] Optionally, the first connecting part and the third connecting part are wound to form a solid or hollow central shaft body; or,

[0021] The flow divider further comprises a solid or hollow central shaft body, and the first connecting part and the third connecting part are wound around the central shaft body, and surfaces of the first connecting part and the third connecting part adjacent to the central shaft body after being wound are fitted to an outer circumferential surface of the central shaft body.

[0022] Optionally, one of the first connecting part and the third connecting part adjacent to the central shaft body after being wound has a dimension in a length direction of the second plate greater than or equal to a circumference of the central shaft body.

[0023] Optionally, one of the second connecting part and the fourth connecting part located at an outermost circle after being wound has a dimension in the length direction of the second plate greater than or equal to one half of a circumference of the outermost circle, and the circumference of the outermost circle is a circumference of an outer circumferential surface of a circle of helical segments adjacent to the one of the second connecting part and the fourth connecting part located at the outermost circle after being wound in the first helical body and the second helical body.

[0024] Optionally, a thickness of the first helical body between two helical surfaces is greater than or equal to 0.15 mm and less than or equal to 0.35 mm.

[0025] As another technical solution, the application further provides a manufacturing method of a flow divider, comprising:

[0026] providing a first plate and a second plate; wherein the second plate is provided with a plurality of hollow parts penetrating through a thickness of the second plate, and the hollow parts constitute flow spaces for fluid to pass through;

[0027] stacking the first plate and the second plate with each other, and the first plate and the second plate are provided with an inlet and an outlet at both ends of each of the hollow parts in a width direction of the second plate, so as to allow fluid to flow into and out of the hollow parts;

[0028] winding the first plate and the second plate stacked with each other together, and a first helical body formed by winding the first plate and a second helical body formed by winding the second plate together constitute a cylindrical main body.

[0029] Optionally, the stacking the first plate and the second plate with each other comprises:

[0030] The first flat plate is located on the side of the second flat plate away from the winding central axis.

[0031] Optionally, the first flat plate comprises a main body part; the size of the hollow part in the width direction of the second flat plate is greater than the width of the main body part.

[0032] The first flat plate and the second flat plate are overlapped with each other, comprising:

[0033] The two edge regions of the hollow part in the width direction of the second flat plate are located outside the two side edges of the main body part, so as to form the inlet or outlet.

[0034] Optionally, the winding first end and the winding last end of the second flat plate are respectively provided with a first connecting part and a second connecting part, the first flat plate comprises a main body part, a third connecting part and a fourth connecting part, the third connecting part and the fourth connecting part are respectively arranged at the two ends of the main body part in the length direction of the main body part, wherein the third connecting part is located at the winding first end of the first flat plate, and the fourth connecting part is located at the winding last end of the first flat plate.

[0035] The first flat plate and the second flat plate are overlapped with each other, comprising:

[0036] The first connecting part and the third connecting part are overlapped with each other and fixedly connected.

[0037] After the first flat plate and the second flat plate overlapped with each other are wound together, further comprising:

[0038] The second connecting part and the fourth connecting part are fixedly connected, and fixedly connected with one of the first spiral body and the second spiral body located at the outermost circle adjacent thereto.

[0039] Optionally, the flow divider further comprises a solid or hollow central shaft body.

[0040] The first flat plate and the second flat plate overlapped with each other are wound together, comprising:

[0041] The first connecting part and the third connecting part wind the central shaft body therein, and the surface of the first connecting part and the third connecting part adjacent to the central shaft body after winding is fitted with the outer peripheral surface of the central shaft body.

[0042] As another technical solution, the application further provides a mass flow measuring device, comprising a measuring main body with a fluid channel, and further comprising the above-mentioned flow divider provided by the application, the flow divider is arranged in the fluid channel.

[0043] The measuring body is further provided with a first detection port and a second detection port, both of which are communicated with the fluid channel and are respectively located at the inlet and outlet of the flow space in the flow divider.

[0044] As another technical solution, the application further provides a mass flow control device, which comprises a measuring body with a fluid channel and a flow divider provided in the fluid channel.

[0045] The measuring body is further provided with a first detection port and a second detection port, both of which are communicated with the fluid channel and are respectively located at the inlet and outlet of the flow space in the flow divider. The mass flow control device further comprises a first pressure sensor and a second pressure sensor, a flow regulating valve and a controller. The first pressure sensor and the second pressure sensor are used for detecting the pressures at the inlet and outlet of the flow space through the first detection port and the second detection port respectively and sending to the controller. The flow regulating valve is arranged on the measuring body and is located downstream of the flow divider and is used for regulating the fluid flow of the fluid channel. The controller is used for controlling the opening degree of the flow regulating valve according to the pressures detected by the first pressure sensor and the second pressure sensor and a set flow value, so that the fluid flow of the fluid channel is equal to the set flow value.

[0046] The application has the following beneficial effects:

[0047] The flow divider and the manufacturing method thereof provided by the application can make the inner cavity shape of the fluid passage for accommodating the flow divider adopted by the flow measurement and control device (such as MFM, MFC and the like) be cylindrical, the processing and installation difficulty of the shape is lower, and the processing cost is lower. Moreover, on the basis that the flow divider constitutes a cylinder as a whole, a plurality of flow spaces for passing fluid are formed in the cylindrical main body and are distributed along the radial direction of the cylindrical main body, each flow space is arranged along the circumferential direction of the cylindrical main body and is constituted between the mutually parallel inner circumferential wall surface and outer circumferential wall surface, since the two curved and extended wall surfaces in parallel can be regarded as two parallel planes after being flattened, and the radial distance and effective flow area of the inner circumferential wall surface and the outer circumferential wall surface are set to make the flow state of the fluid flowing through the flow space be laminar flow, the relationship between the pressure difference on the upstream and downstream sides of the flow divider and the flow can be linear, so that the precision of measurement, control, calibration and the like can be improved when the flow divider is applied to the flow measurement and control device. In addition, by making the plurality of flow spaces be distributed along the radial direction of the cylindrical main body, a plurality of flow spaces can be distributed at different radii around the axis of the cylindrical main body, the flow spaces distributed in multiple layers can effectively reduce the overall size of the flow divider under the condition of the same flow, so that the overall size of the flow divider can be reduced on the basis of being suitable for large flow or super large flow, and the difficulty of production, debugging, calibration, installation, maintenance and the like can be further reduced.

[0048] The mass flow measurement device provided by the application can reduce the overall size of the flow divider on the basis of being suitable for large flow or super large flow, and the difficulty of production, debugging, calibration, installation, maintenance and the like can be further reduced.

[0049] The mass flow control device provided by the application can reduce the overall size of the flow divider on the basis of being suitable for large flow or super large flow, and the difficulty of production, debugging, calibration, installation, maintenance and the like can be further reduced. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 It is a radial section view of the cylindrical main body adopted by the embodiment of the application;

[0051] Figure 2 It is another radial section view of the cylindrical main body adopted by the embodiment of the application;

[0052] Figure 3 It is still another radial section view of the cylindrical main body adopted by the embodiment of the application;

[0053] Figure 4 It is a radial section view of the first flat plate and the second flat plate after being wound.

[0054] Figure 5 Structure diagram of a first flat plate used in an embodiment of the present application when unfolded;

[0055] Figure 6 Structure diagram of a second flat plate used in an embodiment of the present application when unfolded;

[0056] Figure 7 Structure diagram of a first flat plate and a second flat plate used in an embodiment of the present application when unfolded;

[0057] Figure 8 Structure diagram of a hollow center shaft used in an embodiment of the present application; Figure 7 Enlarged view of the C region;

[0058] Figure 9 Structure diagram of a hollow center shaft used in an embodiment of the present application;

[0059] Figure 10 Flow chart of a manufacturing method of a flow divider provided in an embodiment of the present application;

[0060] Figure 11 Axial sectional view of a measuring body of a mass flow measuring device provided in an embodiment of the present application;

[0061] Figure 12 Structure diagram of a mass flow control device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0062] In order to make the technical solution of the present application better understood by those skilled in the art, the flow divider, the mass flow measuring device and the mass flow control device provided in the present application are described in detail below in conjunction with the accompanying drawings.

[0063] Please refer to Figure 1 The present application provides a flow divider, which comprises a cylindrical body 1, a plurality of flow spaces 2 for fluid passing through are formed in the cylindrical body 1 and are distributed along the radial direction of the cylindrical body 1, each flow space 2 is arranged along the circumferential direction of the cylindrical body 1, each flow space 2 is formed between mutually parallel inner circumferential wall surface 2a and outer circumferential wall surface 2b, the inner circumferential wall surface 2a and the outer circumferential wall surface 2b are in the shape of a circular arc and extend along the circumferential direction of the cylindrical body 1, and the radial distance and the effective flow area of the inner circumferential wall surface 2a and the outer circumferential wall surface 2b are set so that the fluid flowing through the flow space 2 is in a laminar flow state.

[0064] By adopting the cylindrical main body 1, the inner cavity shape of the fluid passage for accommodating the flow divider adopted by the flow measurement and control device (such as MFM, MFC, etc.) can be cylindrical, which is lower in processing and installation difficulty and lower in processing cost. Moreover, on the basis that the flow divider constitutes a cylinder as a whole, by forming a plurality of flow spaces 2 in the cylindrical main body 1 and spaced apart along the radial direction of the cylindrical main body 1, the plurality of flow spaces 2 can be distributed at different radii around the axis of the cylindrical main body 1. Such a plurality of flow spaces 2 distributed in multiple layers around the cylindrical main body 1 can effectively reduce the overall size of the flow divider under the condition of the same flow rate, that is, the space utilization of the flow spaces 2 in the above distribution manner is higher. In other words, under the condition of the same overall size, the distribution manner can more easily meet the requirement of large flow rate or super large flow rate of the flow divider. Thus, on the basis of being applicable to large flow rate or super large flow rate, the overall size of the flow divider can be reduced, and the difficulty of production, manufacturing, debugging, calibration, installation, maintenance, etc. can be further reduced.

[0065] Specifically, the plurality of flow spaces 2 are each arranged to extend along the circumferential direction of the cylindrical main body 1, which means that the flow spaces 2 extend in a curved manner around the axis of the cylindrical main body 1 rather than in a straight line. Moreover, the flow spaces 2 can extend in a curved manner around the entire circumference, for example, as shown in Figure 1 each flow space 2 extends in a curved manner to form a closed circular ring-shaped space. Alternatively, the plurality of circular ring-shaped flow spaces 2 are coaxial, and different flow spaces 2 are distributed at different radii around the axis of the cylindrical main body 1. It should be noted that, under the premise of meeting the overall size requirement of the flow divider, the flow spaces 2 can also extend in a curved manner to form a closed elliptical ring-shaped space. Alternatively, the plurality of flow spaces 2 extend in a curved manner to form closed ring-shaped spaces of the same shape but different sizes, so as to enable the plurality of flow spaces 2 to be distributed at different radii around the axis of the cylindrical main body 1 while ensuring that each flow space 2 is formed between mutually parallel inner and outer circumferential wall surfaces 2a and 2b.

[0066] On the basis that the flow divider constitutes a cylinder as a whole, each flow space 2 is formed between mutually parallel inner and outer circumferential wall surfaces 2a and 2b. Since the two curved wall surfaces in parallel can be regarded as two parallel planes after being flattened, and by setting the radial spacing and effective flow area (flow area of the flow space 2) of the inner and outer circumferential wall surfaces 2a and 2b to be such that the flow state of the fluid flowing through the flow space 2 is laminar flow, the relationship between the pressure difference on the upstream and downstream sides of the flow divider and the flow rate can be linear, so as to improve the accuracy of measurement, control, calibration, etc. when applied to the flow measurement and control device.

[0067] In the case where the flow space 2 is a closed ring-shaped space, for example, as shown in Figure 1As shown, the cylindrical body 1 comprises, for example, a plurality of annular bodies 11 coaxial and nested with each other, and two surfaces of each two adjacent annular bodies 11 opposite to each other are respectively an inner circumferential wall surface 2a and an outer circumferential wall surface 2b. Optionally, a flow space 2 is formed between the innermost annular body 11 and the central shaft body 4 surrounding it.

[0068] As shown, the cylindrical body 1 comprises, for example, a plurality of annular bodies 11 coaxial and nested with each other, and two surfaces of each two adjacent annular bodies 11 opposite to each other are respectively an inner circumferential wall surface 2a and an outer circumferential wall surface 2b. Optionally, a flow space 2 is formed between the innermost annular body 11 and the central shaft body 4 surrounding it. Figure 1 As shown, the cylindrical body 1 comprises, for example, a plurality of annular bodies 11 coaxial and nested with each other, and two surfaces of each two adjacent annular bodies 11 opposite to each other are respectively an inner circumferential wall surface 2a and an outer circumferential wall surface 2b. Optionally, a flow space 2 is formed between the innermost annular body 11 and the central shaft body 4 surrounding it.

[0069]

[0070] Wherein, Q is the flow rate of the fluid flowing through the flow space 2; μ is the dynamic viscosity of the fluid; L is the length of the plate (equivalent to the axial length of the inner circumferential wall surface 2a and the outer circumferential wall surface 2b); w is the width of the plate (equivalent to the sum of the effective arc length of the flow space 2 in the circumferential direction); t is the distance between the plates (equivalent to the radial distance between the inner circumferential wall surface 2a and the outer circumferential wall surface 2b); and dp is the flow pressure drop (i.e., the pressure difference between the inlet and outlet of the flow space 2).

[0071] As can be seen from the above relationship, when the fluid flowing through the flow space is in a laminar flow state, the pressure difference dp and the flow rate Q are linearly related, i.e., Q=k×dp=k×(p1-p2), wherein p1 is the pressure at the inlet of the flow space; p2 is the pressure at the outlet of the flow space 2; k is a coefficient related to the thickness of the annular body 11, the flow characteristic length, and other geometric parameters and gas characteristic parameters, and under the condition that the mechanical structure of the flow divider and the dynamic viscosity of the gas are known, k is a constant, therefore, the flow rate Q is only related to the pressure difference dp and is linearly related. When the flow measurement and control device (such as MFM, MFC, etc.) needs to use other gases different from the calibration gas, according to the known pressure difference dp (obtained by measurement) and the dynamic viscosity of the gas, the flow rate Q of the other gas can be calculated through the above linear relationship. The flow rate Q obtained through the linear relationship is more accurate, thereby improving the accuracy of measurement, control, calibration, etc. when applied to the flow measurement and control device.

[0072] In some optional embodiments, the radial distance of the flow space 2 (i.e., the radial distance between the inner circumferential wall surface 2a and the outer circumferential wall surface 2b) and the effective flow area satisfy the condition of making the fluid flow state laminar. The radial distance and the effective flow area can be designed according to the following relationship for calculating the Reynolds number Re. The Reynolds number Re is a flow state discrimination number. When the Reynolds number Re is below a preset critical value, the fluid state is laminar flow; when the Reynolds number Re is in a certain interval greater than the preset critical value, the fluid state is transitional flow; and when the Reynolds number Re is a certain value beyond the above interval, the fluid is turbulent flow. Therefore, whether the radial distance of the flow space 2 (i.e., the radial distance between the inner circumferential wall surface 2a and the outer circumferential wall surface 2b) and the effective flow area satisfy the condition of making the fluid flow state laminar can be determined by judging whether the Reynolds number Re is below the preset critical value. Specifically, the relationship for calculating the Reynolds number Re is as follows:

[0073]

[0074] wherein p is the fluid density, which varies with temperature and pressure, and is calculated under standard conditions (0°C, 1 atm); v is the average flow velocity of the fluid, which is determined by the flow rate and the flow area, and the flow area is the effective flow geometry area perpendicular to the flow direction; L t is the characteristic size of the flow structure.

[0075] For the flow structure of two parallel flat plates (equivalent to the inner circumferential wall surface 2a and the outer circumferential wall surface 2b), the characteristic size is twice the distance t between the flat plates (equivalent to the radial distance between the inner circumferential wall surface 2a and the outer circumferential wall surface 2b), and the distance t is substituted into the above relationship to obtain the following relationship:

[0076]

[0077] wherein m is the mass flow rate of the fluid; and A is the flow area.

[0078] According to the above relationship, the characteristic size L t, the Reynolds number Re corresponding to the fluid type can be obtained according to the above relationship and combined with the flow simulation experiment, for example, the Reynolds number Re corresponding to nitrogen is 1500. It is easy to understand that the radial distance of the flow space 2 (i.e. the radial distance between the inner peripheral wall surface 2a and the outer peripheral wall surface 2b) and the effective flow area are set as long as the actual Reynolds number Re is less than the Reynolds number Re (which can be referred to as the critical Reynolds number Re) obtained according to the above relationship and combined with the flow simulation experiment, so as to ensure that the flow state of various fluids flowing through the flow divider is laminar flow. If the actual Reynolds number Re is greater than the critical Reynolds number Re, the radial distance of the flow space 2 (i.e. the radial distance between the inner peripheral wall surface 2a and the outer peripheral wall surface 2b) and the effective flow area can be adjusted until the actual Reynolds number Re is less than the critical Reynolds number Re. In practical applications, in order to expand the fluid types applicable to the flow divider and ensure that the flow state of various fluids flowing through the flow divider is laminar flow, the critical Reynolds number Re can be 1000, which is half of the conventional value (2000) of the Reynolds number Re.

[0079] In some alternative embodiments, referring to Figure 2 In order to keep the distance between each two adjacent ring bodies 11 unchanged and improve the structural stability and reliability of the flow divider, a plurality of support members 3 are connected between each two adjacent ring bodies 11 and are spaced along the circumferential direction of the ring body 11; the region between the inner peripheral wall surface 2a and the outer peripheral wall surface 2b corresponding to the spacing of each two adjacent support members 3 constitutes a flow space 2'. In this case, the plurality of flow spaces 2' are arranged along the circumferential direction of the cylindrical main body 1 and each flow space 2' is curved to form a non-closed circular arc space with a central angle less than 360°. Moreover, the plurality of circular arc flow spaces 2' are distributed on the circumferences of different radii around the axis of the cylindrical main body 1. This also enables the plurality of flow spaces 2' to be distributed in multiple layers, thereby effectively reducing the overall size of the flow divider under the condition of the same flow rate, and further reducing the overall size of the flow divider on the basis of being applicable to large flow rates or super-large flow rates. Preferably, the plurality of support members 3 are uniformly distributed along the circumferential direction of the ring body 11, so that the arc lengths of the plurality of flow spaces 2' on the same circumference are consistent or substantially consistent.

[0080] In some alternative embodiments, the support member 3 can be, for example, a strip-shaped member and is arranged in the axial direction of the cylindrical main body 1. For the plurality of ring bodies 11, the support member 3 can not only play a supporting role but also play a role of connecting the plurality of ring bodies 11 into a whole. The support member 3 can be connected with the adjacent two ring bodies 11 by welding, bonding, riveting or the like. Of course, the embodiments of the present application are not limited to the strip-shaped support member, and in practical applications, the support member 3 can also adopt any other structure as long as the above functions can be achieved.

[0081] In some alternative embodiments, referring to Figure 3 , the cylindrical body 1' comprises a first spiral 5 wound by a first flat plate, it is easy to understand that the overall shape of the first spiral 5 is approximately a cylinder. The regions of the two spiral surfaces of the first spiral 5 opposite to each other are the inner circumferential wall surface 2a' and the outer circumferential wall surface 2b' which are parallel to each other. A continuous spiral flow space 2" is formed between the inner circumferential wall surface 2a' and the outer circumferential wall surface 2b'. When the thickness between the two spiral surfaces is very small, for example, less than or equal to 0.35 mm, the spiral inner circumferential wall surface 2a' and the outer circumferential wall surface 2b' can be regarded as closed annular surfaces, and the spiral flow space 2" can be regarded as a plurality of coaxial closed annular spaces, i.e., equivalent to Figure 1 the plurality of flow spaces 2 shown in FIG. 1.

[0082] In this case, the cylindrical body 1' which is approximately a cylinder can also make the inner cavity shape of the fluid passage of the flow measurement and control device (such as MFM, MFC, etc.) used to accommodate the flow divider be cylindrical, which is lower in processing and installation difficulty and lower in processing cost. Moreover, since the spiral flow space 2" can be regarded as being composed of a plurality of coaxial annular spaces with different radii when the thickness between the two spiral surfaces is very small, it is also possible to effectively reduce the overall size of the flow divider under the condition of the same flow. At the same time, since the spiral inner circumferential wall surface 2a' and the outer circumferential wall surface 2b' can both be regarded as being composed of a plurality of coaxial annular surfaces with different radii, and the two parallel annular surfaces can be regarded as two parallel rectangular plates after being flattened, the fluid flowing between the inner circumferential wall surface 2a' and the outer circumferential wall surface 2b' can be regarded as flowing between two parallel rectangular plates, so that the same way as the cylindrical body 1 shown in Figure 1 can be used to achieve the laminar flow state of the fluid flowing through the flow space 2", i.e., the flow of the fluid flowing through the spiral flow space 2" can be calculated by using the above relationship of the flow of the fluid in the laminar flow state between two flat plates, in which the width w of the flat plate is equivalent to the arc length of the region of the inner circumferential wall surface 2a' and the outer circumferential wall surface 2b' opposite to each other. Since the way to achieve the laminar flow state of the fluid flowing through the flow space has been described in detail in the corresponding embodiments of Figure 1 , it will not be described here again.

[0083] In some alternative embodiments, referring to Figure 4In order to keep the distance of the spiral flow space at different positions in the spiral direction unchanged and improve the structural stability and reliability of the flow divider, a plurality of support members 64 are arranged between the two spiral surfaces of the first spiral body 5 and are spaced apart in the spiral direction; the region between the inner peripheral wall surface 2a' and the outer peripheral wall surface 2b' corresponding to the interval of each adjacent two support members 64 constitutes a flow space 63, that is, the above-mentioned spiral flow space is divided into a plurality of flow spaces 63 which are spaced apart in the spiral direction by the plurality of support members 64. This can also achieve the multi-layer circumferential distribution of the plurality of flow spaces 63, thereby effectively reducing the overall size of the flow divider under the condition of the same flow, and further reducing the overall size of the flow divider on the basis of being suitable for large flow or super large flow. Preferably, the plurality of support members 64 on the same circumference are uniformly distributed, so that the arc lengths of the plurality of flow spaces 63 on the same circumference are consistent or substantially consistent.

[0084] The plurality of support members 64 can be formed in various ways, for example, as shown in Figures 4 to 9 The flow divider further comprises a second spiral body 6, and the first spiral body 5 and the second spiral body 6 are wound together by the first flat plate 5' and the second flat plate 6' which are stacked with each other, wherein a plurality of hollow portions 63' penetrating the thickness of the second flat plate 6' are arranged on the second flat plate 6', the plurality of hollow portions 63' are arranged at intervals along the length direction of the second flat plate 6', and the interval part between the adjacent two hollow portions 63' of the second flat plate 6' constitutes the above-mentioned support member 64, and the hollow portion 63' constitutes the above-mentioned flow space 63; the first spiral body 5 and the second spiral body 6 are provided with an inlet and an outlet at both ends of each hollow portion 63' in the axial direction of the cylindrical main body 1, so as to allow the fluid to flow into and out of the hollow portion 63'. Since the first flat plate 5' and the second flat plate 6' are stacked with each other and wound together, the solid part of the second flat plate 6' except the hollow portion 63' and the first flat plate 5' support each other, the supporting effect is better, and at the same time, by winding the first flat plate 5' and the second flat plate 6' which are stacked with each other together, the processing and installation difficulty of the flow divider can be further reduced.

[0085] Optionally, the orthogonal projection shape of the hollow portion 63' on the extension surface of the second flat plate 6' is, for example, a rectangle, or can also be a rectangle with rounded corners or chamfered corners.

[0086] In some optional embodiments, as shown in Figure 4 and Figure 5As shown, the first flat plate 5' is located on the side of the second flat plate 6' which is away from the winding central axis (i.e. away from the central shaft body 4), so that after winding, the outermost circle of the first spiral body 5 is located outside the outermost circle of the second spiral body 6, thereby ensuring that the first spiral body 5 can wind each hollow part 63' therein, so as to ensure that each hollow part 63' can be located between two parallel wall surfaces. Of course, in actual application, the second flat plate 6' can also be located on the side of the first flat plate 5' which is away from the winding central axis (i.e. away from the central shaft body 4), so that after winding, the outermost circle of the second spiral body 6 is located outside the outermost circle of the first spiral body 5, which makes the hollow parts 63' distributed on the outermost circle of the second flat plate 6' form a fluid space with the inner wall of the fluid passage after the flow divider is installed in the fluid passage, in which case, the radial distance and effective flow area between the inner circumferential wall surface of the fluid passage and the outer circumferential wall surface of the outermost circle of the second flat plate 6' adjacent thereto can be set to ensure that the fluid flowing through the fluid space is in a laminar flow state.

[0087] In some alternative embodiments, as shown in Figure 6 and Figure 7 As shown, the first flat plate 5' includes a main body portion 53, the size of the hollow part 63' in the width direction of the second flat plate 6' is greater than the width of the main body portion 53, and two edge regions 631 of the hollow part 63' in the width direction of the second flat plate 6' are located outside the two side edges of the main body portion 53 to form an inlet or outlet for fluid to flow into or out of the central region of the hollow part 63'. That is, in the width direction of the second flat plate 6', the two ends of the hollow part 63' protrude from the two side edges of the main body portion 53 by a portion, and the protruding portion is the above-mentioned edge region 631, which does not overlap with the main body portion 53, so that the two ends of the central region of the hollow part 63' in the fluid flow direction (i.e. the direction parallel to the axial direction of the cylindrical body 1) are communicated with the fluid passage where the flow divider is located, so that the above-mentioned two edge regions 631 can serve as the inlet or outlet for fluid to flow into or out of the central region of the hollow part 63'. The length of the above-mentioned edge region 631 in the fluid flow direction is, for example, greater than or equal to 2 mm and less than or equal to 3 mm. It should be noted that the structure of the first spiral body 5 and the second spiral body 6 forming the inlet and outlet at the two ends of each hollow part 63' in the axial direction of the cylindrical body 1 is not limited to being formed by the edge region 631, and in actual application, other arbitrary structures can also be used to achieve the same, as long as the two ends of each hollow part 63' in the axial direction of the cylindrical body 1 can be communicated with the fluid passage where the flow divider is located.

[0088] In some alternative embodiments, as shown in Figure 4 and Figure 6As shown, the dimensions of the multiple hollow portions 63' in the length direction of the second flat plate 6' increase from the winding starting end to the winding ending end of the second flat plate 6'. In this way, multiple support members 64 on the same circumference can be evenly distributed, so that the arc lengths of multiple flow spaces 63 on the same circumference are the same or substantially the same.

[0089] In some optional embodiments, as Figures 5 to 7 shown, a first connection portion 61 and a second connection portion 62 are respectively provided at the winding starting end and the winding ending end of the second flat plate 6'. The first flat plate 5' includes the above-mentioned main body portion 53, a third connection portion 51 and a fourth connection portion 52. The third connection portion 51 and the fourth connection portion 52 are respectively provided at both ends of the main body portion 53 in the length direction of the main body portion 53. Among them, the third connection portion 51 is located at the winding starting end of the first flat plate 5', and the fourth connection portion 52 is located at the winding ending end of the first flat plate 5'; the first connection portion 61 and the third connection portion 51 are overlapped with each other and fixedly connected; the second connection portion 62 and the fourth connection portion 52 are overlapped with each other and fixedly connected. In this way, before winding, the first connection portion 61 and the third connection portion 51 can be fixedly connected first to fix the winding starting ends of the second flat plate 6' and the first flat plate 5' together, and after winding, the second connection portion 62 and the fourth connection portion 52 are fixedly connected, and fixedly connected to the outermost circle of the adjacent first helix 5 to fix the winding ending ends of the second flat plate 6' and the first flat plate 5' together. In this way, it can be ensured that the first helix 5 and the second helix 6 formed after winding can remain overlapped and will not散开, so that a stable approximate cylinder can be formed. There are various ways of the above-mentioned fixed connection, such as welding, bonding or riveting, etc.

[0090] Optionally, as Figure 5 and Figure 6 shown, the first flat plate 5' is in a shape similar to "I", that is, the widths of the above-mentioned third connection portion 51 and the fourth connection portion 52 are equal and greater than the width of the main body portion 53 located between the third connection portion 51 and the fourth connection portion 52; the width of the second flat plate 6' is equal everywhere, and the widths of the first connection portion 61 and the second connection portion 62 are equal to the widths of the third connection portion 51 and the fourth connection portion 52. By making the widths of the first connection portion 61 and the third connection portion 51 equal, it is easier to align the first connection portion 61 and the third connection portion 51 when they are overlapped, so that winding is more convenient. By making the widths of the third connection portion 51 and the fourth connection portion 52 greater than the width of the main body portion 53 located between the third connection portion 51 and the fourth connection portion 52, it can be realized that the two edge regions 631 of the hollow portion 63' in the width direction of the second flat plate 6' are located outside the two side edges of the main body portion 53 to form an inlet and an outlet for the fluid to flow into and out of the hollow portion 63'.

[0091] In some alternative embodiments, the first connecting portion 61 and the third connecting portion 51 are wound to form a solid or hollow center shaft body 4; or the flow divider further comprises a solid or hollow center shaft body 4, and the first connecting portion 61 and the third connecting portion 51 are wound in the center shaft body 4, and the surfaces of the first connecting portion 61 and the third connecting portion 51 adjacent to the center shaft body 4 are fitted with the outer circumferential surface of the center shaft body 4. With the above-mentioned center shaft body 4, it can be more convenient to wind. Alternatively, the first connecting portion 61 and the third connecting portion 51 are fixedly connected with the center shaft body 4, for example, by welding, bonding or riveting, etc. As shown in Figure 9 For the hollow center shaft body 4, the corresponding dimensions need to meet the following conditions: the flow state of the fluid flowing through the hollow center shaft body 4 is laminar flow, and the flow pressure drop at both ends of the center shaft body 4 is equal to the flow pressure drop at both ends of each flow space.

[0092] The flow rate of the fluid in the laminar flow state of the hollow center shaft body 4 meets the following relationship:

[0093]

[0094] Wherein, Q k is the flow rate of the fluid flowing through the hollow center shaft body 4; μ is the dynamic viscosity of the fluid; L k is the axial length of the hollow center shaft body 4 (equal to the axial length of the flow dividing wall), d k is the inner diameter of the hollow center shaft body 4; and dp is the flow pressure drop (i.e. the pressure difference between the inlet and outlet of the flow space).

[0095] For the fluid flowing through the hollow center shaft body 4, the relationship for calculating the Reynolds number Re is:

[0096]

[0097] Wherein, m is the mass flow rate of the fluid; and A is the flow area.

[0098] According to the above relationship, the inner diameter d k of the hollow center shaft body 4 is set as long as the actual Reynolds number Re is less than the critical Reynolds number Re, so that the flow state of various fluids flowing through the hollow center shaft body 4 is laminar flow. In practical applications, a value of the above-mentioned inner diameter d k may be selected first, for example, 1 mm, then the actual Reynolds number Re is calculated and obtained by using the above-mentioned relationship, and it is judged whether it is less than the critical Reynolds number Re. If yes, the current selected value of the inner diameter d k meets the laminar flow condition, and if no, other values of the above-mentioned inner diameter d k need to be selected again, and the above-mentioned calculation process is repeated. It is easy to understand that the above-mentioned inner diameter dk The numerical value is not a fixed value, but a numerical range. In addition, the wall thickness of the hollow central shaft body 4 can be selected as the minimum value, for example, 1 mm, under the premise of meeting the process conditions (for example, welding process conditions) of fixing the first connecting part 61 and the third connecting part 51.

[0099] Optionally, the radial cross-sectional shape of the hollow or solid central shaft body 4 can be circular, square, trapezoidal or any other shape.

[0100] In some optional embodiments, in order to improve the tightness with the central shaft body 4 when the first connecting part 61 and the third connecting part 51 wind the central shaft body 4 therein, one of the first connecting part 61 and the third connecting part 51 adjacent to the central shaft body 4 after winding has a size in the length direction of the second flat plate 6' greater than or equal to the circumference of the central shaft body 4. In this way, the first connecting part 61 and the third connecting part 51 can be wound at least one turn around the central shaft body 4. Figure 4 The thickness and the tightness with the central shaft body 4 of the first connecting part 61 and the third connecting part 51 winding the central shaft body 4 therein are not limited to Figure 4 the structure shown.

[0101] In some optional embodiments, in order to provide reliable support and welding space for the entire cylindrical body 1 after winding to form an approximate cylinder, one of the second connecting part 62 and the fourth connecting part 52 located at the outermost circle after winding has a size in the length direction of the second flat plate 6' greater than or equal to one half of the outer circle circumference length; the outer circle circumference length is the outer circumferential length of the adjacent spiral segment of the first spiral body 5 and the second spiral body 6 to one of the second connecting part 62 and the fourth connecting part 52 located at the outermost circle after winding.

[0102] In a specific embodiment, as Figures 4 to 7As shown, the second flat plate 6' and the main body part 53 are both rectangular flat plates, wherein the first flat plate 5' comprises the main body part 53, the third connecting part 51 and the fourth connecting part 52, the third connecting part 51 and the fourth connecting part 52 are respectively arranged at the two ends of the main body part 53 in the length direction of the main body part 53, wherein the third connecting part 51 is located at the winding starting end of the first flat plate 5', and the fourth connecting part 52 is located at the winding ending end of the first flat plate 5'; the size wa of the third connecting part 51 in the length direction of the first flat plate 5' is smaller than the size we1 of the fourth connecting part 52 in the length direction of the first flat plate 5', and the size we1 is set considering that after winding to form an approximate cylinder, the second connecting part 62 and the fourth connecting part 52 can provide reliable support and welding space for the entire cylinder. The width L1 of the third connecting part 51 and the fourth connecting part 52 is greater than the width Lnf of the main body part 53 between the third connecting part 51 and the fourth connecting part 52, and is equal to the width L2 of the second flat plate 6. The thickness of the first flat plate 5' is t1, and the length is w1.

[0103] The second flat plate 6' is provided with a plurality of hollow parts 63' penetrating through the thickness thereof, the plurality of hollow parts 63' are arranged at intervals in the length direction of the second flat plate 6', and the hollow parts 63' constitute the flow space 63. The size of the hollow part 63' in the length direction of the second flat plate 6' is Wf, the size of the hollow part 63' in the width direction of the second flat plate 6' is Lf, and the interval between adjacent hollow parts 63' is wg. The thickness of the second flat plate 6' is t2, and the length is w2. The second flat plate 6' has the first connecting part 61 and the second connecting part 62, and the size wb of the first connecting part 61 in the length direction of the second flat plate 6' is greater than the size we2 of the second connecting part 62 in the length direction of the second flat plate 6. Among the above-mentioned sizes of the first flat plate 5' and the second flat plate 6', L1=L2, w1=w2, t1=t2.

[0104] After the first flat plate 5' and the second flat plate 6' are stacked on each other, and before winding, the second flat plate 6' is on the top, and the first flat plate 5' is on the bottom, and the first connecting part 61 and the third connecting part 51 are stacked on each other and fixedly connected; after winding, the second connecting part 62 and the fourth connecting part 52 are stacked on each other and fixedly connected, and are fixedly connected with one of the first spiral body 5 and the second spiral body 6 located at the outermost circle. Optionally, a central shaft body 4 is placed on the first connecting part 61, the central shaft body 4 can be solid or hollow, and the central shaft body 4 is tightly attached to the first connecting part 61 and welded together. The size wa of the third connecting part 51 in the length direction of the first flat plate 5', and the size we2 of the second connecting part 62 in the length direction of the second flat plate 6' are set as long as they meet the size requirements of the welding process, for example, 3mm or the like.

[0105] The size Lf of the hollow part 63' in the width direction of the second flat plate 6' is greater than the width Lnf of the main body part 53 between the third connecting part 51 and the fourth connecting part 52, and two edge areas 631 of the hollow part 63' in the width direction of the second flat plate 6' are located outside the two side edges of the main body part 53 to form an inlet or an outlet for fluid flowing into or out of the hollow part 63', which is used to communicate with the pressure detection inlet and the pressure detection outlet to enable the pressure sensor to detect the pressure at the inlet and the outlet of the flow space 63 via the pressure detection inlet and the pressure detection outlet respectively. The sizes of the two edge areas 631 in the width direction of the second flat plate 6' are Lfi and Lfo respectively, where Lf-Lnf=Lfi+Lfo, and Lfi=Lfo. Lfi and Lfo are the inlet length and the outlet length respectively. According to the above relationship (i.e. ), which is satisfied by the flow rate of the fluid in the laminar state between the flat plates, L is the effective length of the fluid flowing in the flow space, i.e. the difference between the total length of the hollow part 63' and the lengths of the two edge areas 631, i.e. the width Lnf of the main body part 53. The distance t between the flat plates is the thickness t1 of the first flat plate 5'.

[0106] In some optional embodiments, in order to obtain a larger flow space and improve the ease of winding as much as possible, the thicknesses t1 and t2 of the first flat plate 5' and the second flat plate 6' should be as small as possible, but should not be too small to ensure that the first flat plate 5' and the second flat plate 6' have sufficient strength so that the involute-shaped flow division walls of each coil after winding have sufficient support. The material of the first flat plate 5' and the second flat plate 6' is, for example, stainless steel, and the thicknesses t1 and t2 of the first flat plate 5' and the second flat plate 6' can be, for example, 0.15mm-0.35mm. By adopting this range of values, the spiral flow space formed between the first spiral body 5 and the second spiral body 6 can be regarded as being composed of coaxial circular annular spaces with different radii, and the two parallel circular annular surfaces can be regarded as two parallel rectangular flat plates after being flattened. Therefore, the fluid flowing between the inner peripheral wall surface 2a' and the outer peripheral wall surface 2b' can be regarded as flowing between two parallel rectangular flat plates, so that the fluid flowing through the above-mentioned flow space 2" can be in a laminar state in the same way as the cylindrical main body 1 shown in Figure 1 .

[0107] As another technical solution, please refer to Figure 10 , and in combination with Figures 4 to 7 , the present embodiment also provides a manufacturing method of a flow divider, which comprises:

[0108] S1, providing a first flat plate 5' and a second flat plate 6'; wherein the second flat plate 6' is provided with a plurality of hollow parts 63' penetrating through the thickness thereof, and the hollow parts 63' form a flow space 63 for fluid to pass through;

[0109] S2, the first plate 5' and the second plate 6' are overlapped with each other, and the first plate 5' and the second plate 6' are provided with an inlet and an outlet at both ends of each hollow part 63' along the width direction of the second plate 6' to allow fluid to flow into and out of the hollow part 63';

[0110] S3, the overlapped first plate 5' and the second plate 6' are wound together, and the first spiral body 5 formed by winding the first plate 5' and the second spiral body 6 formed by winding the second plate 6' together constitute a cylindrical main body 1.

[0111] Since the first plate 5' and the second plate 6' are overlapped with each other, the solid part of the second plate 6' other than the hollow part 63' and the first plate 5' support each other after being wound together, and the support effect is better, and at the same time, by winding the overlapped first plate 5' and the second plate 6' together, the processing and installation difficulty of the flow divider can be further reduced.

[0112] In some optional embodiments, the above step S2 specifically comprises:

[0113] The first plate 5' is located on the side of the second plate 6' away from the winding central axis (i.e., away from the central shaft body 4).

[0114] In this way, after winding, the outermost circle of the first spiral body 5 is located outside the outermost circle of the second spiral body 6, so that the first spiral body 5 can wind each hollow part 63' therein to ensure that each hollow part 63' can be located between two parallel wall surfaces.

[0115] In some optional embodiments, the first plate 5' comprises a main body part 53, and the size of the hollow part 63' in the width direction of the second plate 6' is greater than the width of the main body part 53;

[0116] The above step S2 specifically comprises:

[0117] The two edge regions 631 of the hollow part 63' in the width direction of the second plate 6' are located outside the two side edges of the main body part 53 to constitute the above-mentioned inlet or outlet.

[0118] That is to say, in the width direction of the second flat plate 6', the two ends of the hollow part 63' protrude a part relative to the two side edges of the main body part 53, and the protruding part is the above-mentioned edge region 631, which does not overlap with the main body part 53, so that the two ends of the central region of the hollow part 63' in the fluid flow direction (i.e. the direction parallel to the axial direction of the cylindrical main body 1) can be communicated with the fluid channel where the flow divider is located, so that the above-mentioned two edge regions 631 can serve as the inlet or outlet of the hollow part 63' for the fluid flowing into or out of the central region of the hollow part.

[0119] In some optional embodiments, as shown in Figures 5 to 7 The first flat plate 5' includes the above-mentioned main body part 53, a third connecting part 51 and a fourth connecting part 52, the third connecting part 51 and the fourth connecting part 52 are respectively arranged at the two ends of the main body part 53 in the length direction of the main body part 53, wherein the third connecting part 51 is located at the winding starting end of the first flat plate 5', and the fourth connecting part 52 is located at the winding ending end of the first flat plate 5';

[0120] The above-mentioned step S2 specifically includes:

[0121] The first connecting part 61 and the third connecting part 51 are overlapped with each other and fixedly connected;

[0122] After the above-mentioned step S3 is completed, it further includes:

[0123] The second connecting part 62 and the fourth connecting part 52 are fixedly connected, and fixedly connected with one of the first spiral body 5 and the second spiral body 6 located at the outermost circle adjacent thereto.

[0124] In some optional embodiments, the flow divider further includes a solid or hollow central shaft body 4, in this case, the above-mentioned step S3 specifically includes:

[0125] The first connecting part 61 and the third connecting part 51 wrap the central shaft body 4 therebetween, and the surface of the wrapped first connecting part 61 and the third connecting part 51 adjacent to the central shaft body 4 is fitted with the outer peripheral surface of the central shaft body 4.

[0126] As another technical solution, please refer to Figure 11 The embodiment of the present application also provides a mass flow measuring device, for example, a mass flow meter (MFM), which includes a measuring main body 101 having a fluid channel 102, and further includes the above-mentioned flow divider 103 provided by the embodiment of the present application, which is arranged in the fluid channel 102.

[0127] The measuring body 101 is further provided with a first detection port 104 and a second detection port 105, both of which are in communication with the fluid channel 101 and are located at the inlet 531a and the outlet 531b of the flow space in the flow divider 103, for example, the two edge regions 631 of the hollow part 63' in the width direction of the second plate 6' to form the inlet or outlet for the fluid to flow into or out of the hollow part 63', which are used to communicate with the first detection port 104 and the second detection port 105 respectively. The mass flow measuring device further comprises a first pressure sensor and a second pressure sensor for detecting the pressure at the inlet and outlet of the flow space through the first detection port 104 and the second detection port 105 respectively.

[0128] Since the relationship between the pressure difference on the upstream and downstream sides of the flow divider 103 and the flow rate is a linear relationship, i.e. Q=k x dp=k x (p1-p2), where p1 is the pressure at the inlet 531a of the flow space; p2 is the pressure at the outlet 531b of the flow space; k is a coefficient related to the geometric parameters and gas characteristic parameters of the flow divider thickness, flow characteristic length, etc., and k is a constant under the condition of known mechanical structure of the flow divider and gas dynamic viscosity, therefore, the flow rate Q is only related to the pressure difference dp and has a linear relationship. When the mass flow measuring device (such as MFM) needs to use other gases different from the calibration gas, according to the known pressure difference dp (obtained by measurement) and the gas dynamic viscosity, the flow rate Q of other gases can be calculated through the above linear relationship. The flow rate Q obtained by linear relationship calculation is more accurate, so as to improve the accuracy of measurement, control, calibration, etc. when applied to flow measurement and control device.

[0129] In some optional embodiments, the side of the measuring body 101 close to the inlet 531a of the flow divider 103 is provided with a fluid inlet 106, which is in communication with the inlet 531a, and an annular step is arranged on the end surface 101a of the fluid inlet 106 opposite to the flow divider 103, the step surface 101b of the annular step abuts against the end surface of the side of the flow divider 103 close to the inlet 531a, so as to limit the position of the flow divider 103 in the fluid channel 102. On this basis, the outlet 531b of the flow divider 103 in the fluid channel 102 is provided with a locking ring 120, which is used in cooperation with the step surface 101b described above, so as to lock the position of the flow divider 103 in the fluid channel 102 and avoid axial displacement of the flow divider 103. The outer peripheral wall of the locking ring 120 can be threadedly connected with the inner thread of the inner wall of the fluid channel 102, or the outer peripheral wall of the locking ring 120 can be in interference fit with the inner wall of the fluid channel 102, so as to realize the relative fixation of the locking ring 120 and the fluid channel 102. In addition, the side of the measuring body 101 close to the outlet 531b of the flow divider 103 is provided with a fluid outlet 107, which is in communication with the outlet 531b. The fluid (such as gas or liquid) first enters the fluid channel 102 through the fluid inlet 106, and then flows into the first detection port 104 and each fluid space 63 in the flow divider 103 through the inlet 531a at the same time, and the fluid in each fluid space 63 and the second detection port 105 flows out through the outlet 531b, and finally flows out of the fluid channel 102 through the fluid outlet 107.

[0130] The mass flow measuring device provided by the embodiment of the present application can reduce the overall size of the flow divider on the basis of being applicable to large flow or super-large flow, and further can reduce the difficulty of production and manufacturing, debugging and calibration, installation, maintenance and the like.

[0131] As another technical solution, refer to Figure 12 The embodiment of the present application further provides a mass flow control device, for example, a mass flow controller (MFC), which comprises a measuring body 101 having a fluid channel 102, and further comprises the above-mentioned flow divider 103 provided by the embodiment of the present application, which is arranged in the fluid channel 102.

[0132] The measuring body 101 is further provided with a first detection port 104 and a second detection port 105, both of which are in communication with the fluid channel 102 and are located at the inlet 531a and the outlet 531b of the flow space in the flow divider 103, for example, two edge regions 631 of the hollow part 63' in the width direction of the second plate 6' to form an inlet or an outlet for fluid flowing into or out of the hollow part 63', and the inlet 531a and the outlet 531b are used to communicate with the first detection port 104 and the second detection port 105 respectively. In addition, the measuring body 101 is provided with a fluid inlet 106 and a fluid outlet 107 at both ends of the fluid channel 102, both of which are in communication with the fluid channel 102 and are used for fluid flowing into or out of the fluid channel 102.

[0133] The mass flow measuring device further comprises a first pressure sensor 209, a second pressure sensor 210, a flow regulating valve 206 and a controller 207, the first pressure sensor 209 and the second pressure sensor 210 are used to detect the pressures p1 and p2 at the inlet 531a and the outlet 531b of the flow space through the first detection port 104 and the second detection port 105 respectively and send to the controller 207; the flow regulating valve 206 is arranged on the measuring body 101 and is located downstream of the flow divider 103 and is used to regulate the fluid flow of the fluid channel 102. The controller 207 is used to control the opening of the flow regulating valve 206 according to the pressures detected by the first pressure sensor 209 and the second pressure sensor 210 and the set flow value, so that the fluid flow of the fluid channel 102 is equal to the set flow value.

[0134] Optionally, the mass flow control device provided by the embodiment of the present application can further comprise a pressure difference sensor 208 connected with the first pressure sensor 209 and the second pressure sensor 210 respectively, used to receive the pressures p1 and p2 at the inlet 531a and the outlet 531b of the flow space sent by the first pressure sensor 209 and the second pressure sensor 210 respectively, calculate the difference value, i.e. the pressure difference, and send to the controller 207; the controller 207 is used to calculate the actual flow according to the linear relationship between the pressure difference and the flow, compare the actual flow with the set flow, and send a control signal to the flow regulating valve 206 according to the comparison result; the flow regulating valve 206 is used to adjust the fluid flow at the outlet of the fluid channel 102 according to the control signal, so that it is consistent with the set flow.

[0135] The mass flow control device provided by the embodiment of the present application can reduce the overall size of the flow divider on the basis of being applicable to large flow or super large flow, and further can reduce the difficulty of production, debugging, calibration, installation, maintenance and the like.

[0136] It is understood that the above embodiments are only exemplary for illustrating the principles of the present application, and the present application is not limited thereto. Various modifications and improvements can be made by those skilled in the art without departing from the spirit and scope of the present application, and these modifications and improvements are also considered as the protection scope of the present application.

Claims

1. A flow diverter, characterized by, The flow divider comprises a cylindrical body, in which a plurality of flow spaces for fluid passing through are formed and are distributed along the radial direction of the cylindrical body, each of the flow spaces is arranged along the circumferential direction of the cylindrical body; Each of the flow spaces is formed between mutually parallel inner and outer circumferential wall surfaces, the radial distance and effective flow area of the inner and outer circumferential wall surfaces are arranged to make the fluid flowing through the flow space in a laminar flow state; The cylindrical body comprises a first spiral body wound by a first flat plate, the regions of the two spiral surfaces of the first spiral body opposite to each other are the inner and outer circumferential wall surfaces.

2. The shunt of claim 1, wherein, A plurality of supports are arranged between the two spiral surfaces of the first spiral body and are distributed along the spiral direction; the region between the inner and outer circumferential wall surfaces corresponding to the interval of each adjacent two supports constitutes the flow space.

3. The shunt of claim 2, wherein, The flow divider further comprises a second spiral body, the first spiral body and the second spiral body are wound together by the first flat plate and a second flat plate stacked with each other, wherein, A plurality of hollow parts penetrating through the thickness of the second flat plate are arranged on the second flat plate, the plurality of hollow parts are arranged along the length direction of the second flat plate, the interval part of the second flat plate between adjacent two hollow parts constitutes the support, and the hollow part constitutes the flow space; The first spiral body and the second spiral body constitute an inlet and an outlet at the two ends of each hollow part along the axial direction of the cylindrical body, so as to allow fluid to flow into and out of the hollow part.

4. The shunt of claim 3, wherein, The first flat plate is located on the side of the second flat plate away from the winding central axis.

5. The shunt of claim 3, wherein, The first flat plate comprises a main part; the size of the hollow part in the width direction of the second flat plate is greater than the width of the main part, and the two edge regions of the hollow part in the width direction of the second flat plate are located outside the two side edges of the main part, so as to constitute the inlet or outlet.

6. The shunt of claim 3, wherein, The size of the plurality of hollow parts in the length direction of the second flat plate increases from the winding starting end to the winding ending end of the second flat plate.

7. The shunt according to any of claims 3-6, wherein, The winding starting end and the winding ending end of the second flat plate are respectively provided with a first connecting part and a second connecting part, the first flat plate comprises a main part, a third connecting part and a fourth connecting part, the third connecting part and the fourth connecting part are respectively arranged at the two ends of the main part in the length direction of the main part, wherein the third connecting part is located at the winding starting end of the first flat plate, and the fourth connecting part is located at the winding ending end of the first flat plate; The first connecting part and the third connecting part are stacked with each other and are fixedly connected; the second connecting part and the fourth connecting part are stacked with each other and are fixedly connected.

8. The shunt of claim 7, wherein, The first connecting part and the third connecting part are wound to form a solid or hollow central shaft body; or, The flow divider further comprises a solid or hollow central shaft body, the first connecting part and the third connecting part are wound in the central shaft body, and the surface of the first connecting part and the third connecting part adjacent to the central shaft body after winding is fitted with the outer circumferential surface of the central shaft body.

9. The shunt of claim 8, wherein, One of the first connecting portion and the third connecting portion, which is adjacent to the central axis body after winding, has a dimension in the length direction of the second plate that is greater than or equal to the circumference of the central axis body.

10. The shunt of claim 8, wherein, One of the second connecting portion and the fourth connecting portion, which is located at the outermost circle after winding, has a dimension in the length direction of the second plate that is greater than or equal to one-half of the outermost circle circumference, which is the outer circumferential surface length of one circle of helical segments of the first helical body and the second helical body that is adjacent to the one of the second connecting portion and the fourth connecting portion located at the outermost circle after winding.

11. The shunt of claim 1, wherein, The thickness of the first helical body between the two helical surfaces is greater than or equal to 0.15 mm and less than or equal to 0.35 mm.

12. A method of manufacturing a shunt, characterized by The method comprises: providing a first plate and a second plate, wherein the second plate is provided with a plurality of hollow portions that pass through the thickness of the second plate, and the hollow portions form flow spaces for fluid to pass through; stacking the first plate and the second plate on each other, and the first plate and the second plate form an inlet and an outlet at both ends of each hollow portion in the width direction of the second plate, so as to allow fluid to flow into and out of the hollow portion; winding the first plate and the second plate that are stacked on each other together, and the first helical body formed by winding the first plate and the second helical body formed by winding the second plate together form a cylindrical main body.

13. The method of manufacturing a shunt according to claim 12, wherein, The method comprises: stacking the first plate and the second plate on each other, and the first plate and the second plate form an inlet and an outlet at both ends of each hollow portion in the width direction of the second plate, so as to allow fluid to flow into and out of the hollow portion; 14. The method of manufacturing a shunt according to claim 12, wherein, winding the first plate and the second plate that are stacked on each other together, and the first helical body formed by winding the first plate and the second helical body formed by winding the second plate together form a cylindrical main body. The method comprises: stacking the first plate and the second plate on each other, and the first plate and the second plate form an inlet and an outlet at both ends of each hollow portion in the width direction of the second plate, so as to allow fluid to flow into and out of the hollow portion; 15. The method of manufacturing a shunt according to claim 12, wherein, The winding first end and the winding last end of the second plate are respectively provided with a first connecting portion and a second connecting portion, the first plate comprises a main body portion, a third connecting portion and a fourth connecting portion, the third connecting portion and the fourth connecting portion are respectively provided at both ends of the main body portion in the length direction of the main body portion, wherein the third connecting portion is located at the winding first end of the first plate, and the fourth connecting portion is located at the winding last end of the first plate. The method comprises: stacking the first connecting portion and the third connecting portion on each other, and fixedly connecting them; after the winding of the first plate and the second plate that are stacked on each other together is completed, the method further comprises: fixedly connecting the second connecting portion and the fourth connecting portion, and fixedly connecting them with the one of the first helical body and the second helical body located at the outermost circle.

16. The method of manufacturing a shunt according to claim 15, wherein, The flow divider further comprises a solid or hollow central axis body. The method comprises: The first connecting portion and the third connecting portion wrap the center shaft body therein, and surfaces of the first connecting portion and the third connecting portion adjacent to the center shaft body after being wrapped are fitted to an outer circumferential surface of the center shaft body.

17. A mass flow measuring device comprising a measuring body having a fluid passage, characterized in that The shunt according to any one of claims 1-11 is arranged in the fluid passage; The measuring body is further provided with a first detection port and a second detection port, both of which communicate with the fluid passage and are respectively located at the inlet and outlet of the flow space in the shunt, and the mass flow measuring device further comprises a first pressure sensor and a second pressure sensor for detecting the pressures at the inlet and outlet of the flow space through the first detection port and the second detection port respectively.

18. A mass flow control device comprising a measurement body having a fluid passage, characterized by, The shunt according to any one of claims 1-11 is arranged in the fluid passage; The measuring body is further provided with a first detection port and a second detection port, both of which communicate with the fluid passage and are respectively located at the inlet and outlet of the flow space in the shunt, and the mass flow control device further comprises a first pressure sensor, a second pressure sensor, a flow regulating valve and a controller, the first pressure sensor and the second pressure sensor are used to detect the pressures at the inlet and outlet of the flow space through the first detection port and the second detection port respectively and send to the controller, and the flow regulating valve is arranged on the measuring body downstream of the shunt and is used to regulate the fluid flow of the fluid passage; The controller is used to control the opening degree of the flow regulating valve according to the pressures detected by the first pressure sensor and the second pressure sensor and a set flow value, so that the fluid flow of the fluid passage is equal to the set flow value.

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