Laminar flow element and mass flow controller

Abstract

The utility model belongs to the technical field of flow control devices, and provides a laminar flow element and a mass flow controller, the laminar flow element comprises a sleeve, the sleeve comprises a first section and a second section which are arranged along a first direction, and the inner surface of the second section is provided with an internal thread; the plunger is arranged in the sleeve; the plunger comprises a third section and a fourth section which are arranged in the first direction, an annular laminar flow gap is defined by the third section and the first section, and the area of the cross section of the laminar flow gap is gradually decreased in the direction from the third section to the fourth section; at least one of the second section and the fourth section is provided with a channel, the channel extends in the first direction, the channel is communicated with the laminar flow gap, and the channel is communicated with the two ends of the sleeve in the first direction; and an external thread is arranged on the outer surface of the fourth section and is in threaded connection with the internal thread. According to the laminar flow element provided by the embodiment of the invention, the technical problem that the sleeve cannot be used after assembly errors are solved.

Description

Technical Field

[0001] The present application belongs to the technical field of flow control devices, and specifically relates to a laminar flow element and a mass flow controller. Background Art

[0002] Laminar flow elements have accurate flow resistance values ​​and stable laminar flow states. Currently, mature laminar flow elements usually have three structures: capillary, plunger and laminated. The plunger-type laminar flow element is composed of a plunger and a sleeve. The gap between the plunger and the sleeve constitutes a laminar flow channel, which has high requirements for assembly. The size and linearity of the flow resistance depend on the coaxiality and assembly gap of the assembly.

[0003] The existing plunger-type laminar flow element has a strip-shaped protrusion structure on its circumferential surface. The protrusion structure of the plunger is fixed to the inner wall surface of the sleeve by interference fitting. During assembly, the protrusion structure squeezes the inner wall surface of the sleeve and causes plastic deformation of the inner wall surface. If an assembly error occurs, the sleeve cannot be reused. Utility Model Content

[0004] The purpose of the embodiments of the present application is to provide a laminar flow element and a mass flow controller to solve the technical problem in the prior art that the sleeve cannot be used after the plunger-type laminar flow element is assembled incorrectly.

[0005] In the first aspect, the present application provides a laminar flow element, comprising: a sleeve, the sleeve comprising a first section and a second section arranged along a first direction, the inner surface of the second section being provided with an internal thread; a plunger, the plunger being arranged in the sleeve; the plunger comprising a third section and a fourth section arranged along the first direction, the third section and the first section forming an annular laminar gap, the cross-sectional area of ​​the laminar gap gradually decreasing along the direction from the third section to the fourth section; a channel is provided on at least one of the second section and the fourth section, the channel extending along the first direction, the channel being connected with the laminar gap, and the channel connecting the two ends of the sleeve along the first direction; the outer surface of the fourth section is provided with an external thread, and the external thread is threadedly connected with the internal thread.

[0006] The beneficial effects of this embodiment are as follows: the sleeve and the plunger are screwed together by means of internal and external threads, so that the plunger does not need to be fixed to the sleeve by means of squeezing the sleeve, and the sleeve will not undergo plastic deformation. Even if the plunger is screwed in too much when assembled in the sleeve, the position of the plunger can be readjusted by screwing the plunger out, and the sleeve can continue to be used after an assembly error, thereby reducing the scrap rate of the sleeve; at the same time, the coaxial degree of the sleeve and the plunger is made higher through the coaxial connection of the internal and external threads, making the laminar gap more uniform and the laminar state more stable; the provision of a channel can ensure that the fluid continues to flow after flowing out of the laminar gap on the basis of the threaded connection, thereby ensuring the stability of the laminar flow element.

[0007] In some embodiments, the first section has an inner conical surface extending along the first direction, the third section has an outer conical surface, the inner conical surface is coaxially arranged with the outer conical surface, and the outer conical surface and the inner conical surface enclose the laminar flow gap.

[0008] The beneficial effects of this embodiment are as follows: the coaxial outer cone surface and the inner cone surface form a laminar flow gap, so that the cross-section of the laminar flow gap changes more evenly, the flow resistance changes more evenly, and the laminar flow state is more stable.

[0009] In some embodiments, the sleeve and the plunger are fixedly connected at the connection between the external thread and the internal thread.

[0010] The beneficial effects of this embodiment are: fixing the sleeve and the plunger to each other can avoid shaking after the sleeve and the plunger are screwed together, thereby ensuring the stability of the assembly and making the flow resistance of the laminar flow element more stable; fixing at the connection between the external thread and the internal thread can avoid affecting the fluid in the channel.

[0011] In some embodiments, the fourth section is a cylindrical structure; the channels are provided in plurality and are grooves, and the channels are provided on at least one of the outer peripheral surface of the fourth section and the inner surface of the second section; the external thread is provided in plurality of sections, and the plurality of sections of the external thread and the plurality of the channels are alternately provided around the first direction.

[0012] The beneficial effects of this embodiment are as follows: multiple channels and external threads are alternately arranged, so that the multiple external threads are spaced apart around the first direction, so that the sleeve and the plunger are threadedly connected at multiple positions, and the connection between the sleeve and the plunger is more stable; at the same time, multiple channels are spaced apart around the first direction, so that the fluid at different positions at the end of the laminar flow gap can be dispersed into the channel to flow backward, thereby reducing flow resistance and making the fluid flow more stable.

[0013] In some embodiments, the sum of central angles of the plurality of channels around the first direction is greater than 180°.

[0014] The beneficial effect of this embodiment is that the sum of the central angles of the multiple channels around the first direction is greater than 180°, and the flow resistance is reduced by limiting the range of the channel, so that the fluid flows more stably in the channel.

[0015] In some embodiments, a plurality of the channels are arranged at equal intervals around the first direction.

[0016] The beneficial effects of this embodiment are as follows: a plurality of channels are arranged at equal intervals around the first direction, so that the distribution of the channels is more uniform, the distribution of the flow resistance is more uniform, the flow state of the fluid at different positions is more consistent, and the fluid flow is more stable.

[0017] In some embodiments, the cross-sectional areas of the plurality of channels are equal.

[0018] The beneficial effect of this embodiment is that the cross-sectional areas of the multiple channels are equal, so the flow resistance of the channels is more consistent, making the flow state of the fluid in different channels more consistent and making the fluid flow more stable.

[0019] In some embodiments, the end of the channel is flush with the end of the third segment.

[0020] The beneficial effects of this embodiment are as follows: when a part of the outer cone surface is located in the second section, the change in the gap between the outer cone surface and the second section is inconsistent with the change in the laminar gap, and the channel is flush with the end of the third section, so that the channel and the laminar gap are directly connected, avoiding the fluid from flowing through a distance between the outer cone surface and the second section before entering the channel, allowing the fluid in the laminar gap to directly enter the channel, making the fluid flow more stable.

[0021] In some embodiments, the sleeve is provided with a first flow channel hole and a second flow channel hole at two ends along the first direction, respectively, and the first flow channel hole and the second flow channel hole are connected to the inside and outside of the sleeve.

[0022] The beneficial effects of this embodiment are as follows: the first flow channel hole and the second flow channel hole are provided to facilitate the connection between the laminar flow element and the flow diversion pipeline, and to facilitate the use of the laminar flow element during flow diversion.

[0023] In a second aspect, the present application further provides a mass flow controller, comprising the laminar flow element described in any one of the embodiments in the first aspect.

[0024] The beneficial effects of this embodiment are as follows: using the laminar flow element of the first aspect for a mass flow controller can provide a more accurate and stable flow resistance, the flow rate calculated based on the flow resistance of the laminar flow element is more accurate, and the control of the fluid flow rate is also more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0026] Figure 1 A schematic diagram of the structure of a laminar flow element provided in an embodiment of the present application;

[0027] Figure 2 A schematic diagram of a plunger provided in an embodiment of the present application;

[0028] Figure 3 A schematic diagram of the distribution of channels and external threads provided in an embodiment of the present application;

[0029] Figure 4 A schematic diagram of a mass flow controller provided in an embodiment of the present application;

[0030] Figure 5 Schematic diagram of the connection between the laminar flow element and the main body provided in the embodiment of the present application.

[0031] Among them, the reference numerals in the figure are:

[0032] 100. Mass flow controller;

[0033] 10. laminar flow element; 11. sleeve; 111. first section; 1111. inner cone; 112. second section; 1121. inner thread; 113. first flow channel hole; 114. second flow channel hole; 12. plunger; 121. third section; 1211. outer cone; 122. fourth section; 1221. outer thread; 1222. channel; 13. laminar flow gap;

[0034] 20. Shunt pipe;

[0035] 30. Main body; 31. Inflow cavity; 32. Outflow cavity. DETAILED DESCRIPTION

[0036] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0037] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0038] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0039] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0040] In a first aspect, the present application provides a laminar flow element. Figure 1 and Figure 2 The laminar flow element 10 includes a sleeve 11 and a plunger 12, the sleeve 11 includes a first section 111 and a second section 112 arranged along a first direction, the inner surface of the second section 112 is provided with an internal thread 1121; the X direction in the figure is the first direction; the plunger 12 is arranged in the sleeve 11; the plunger 12 includes a third section 121 and a fourth section 122 arranged along the first direction, the third section 121 and the first section 111 form an annular laminar gap 13, and the cross-sectional area of ​​the laminar gap 13 gradually decreases along the direction from the third section 121 to the fourth section 122; at least one of the second section 112 and the fourth section 122 is provided with a channel 1222, the channel 1222 extends along the first direction, the channel 1222 is connected to the laminar gap 13, and the channel 1222 is connected to both ends of the sleeve 11 along the first direction; the outer surface of the fourth section 122 is provided with an external thread 1221, and the external thread 1221 is screwed with the internal thread 1121.

[0041] The sleeve 11 and the plunger 12 both extend in the first direction. The sleeve 11 is a tubular structure with openings at both ends along the first direction. The end of the sleeve 11 along the first direction is used to connect to a pipe where the fluid is located, so that the fluid flows through the sleeve 11, and the fluid flows from the first section 111 to the second section 112; the plunger 12 extends in the first direction and generates resistance to the fluid in the sleeve 11.

[0042] The gap between the first section 111 and the third section 121 is a laminar gap 13. Optionally, one of the inner circumferential surface of the first section 111 and the outer circumferential surface of the third section 121 is a cylindrical surface, and the other is a conical surface, and the diameter of the conical surface gradually decreases along the direction from the third section 121 to the fourth section 122. Then, the cross-sectional area of ​​the laminar gap 13 between the first section 111 and the third section 121 gradually decreases along the direction from the third section 121 to the fourth section 122.

[0043] Optionally, the second section 112 is a cylindrical structure, the fourth section 122 is a cylindrical structure, and the diameter of the fourth section 122 is equal to the diameter of the third section 121 .

[0044] The internal thread 1121 and the external thread 1221 are used to connect the plunger 12 to the sleeve 11, and the axes of the internal thread 1121 and the external thread 1221 extend along the first direction; when installing the plunger 12, the fourth section 122 of the plunger 12 is inserted into the sleeve 11 from the first section 111 of the sleeve 11, and the plunger 12 is rotated to make the fourth section 122 and the second section 112 threadedly connected. When adjusting the flow resistance, rotating the plunger 12 forward can make the third section 121 move toward the direction close to the second section 112, and the plunger 12 enters the sleeve 11 forward, the distance between the first section 111 and the third section 121 in the first direction perpendicular to the first direction becomes smaller, the cross-section of the laminar gap 13 becomes smaller, and the flow resistance of the laminar gap 13 becomes larger; rotating the plunger 12 backward can make the fourth section 122 move toward the direction close to the first section 111, and the plunger 12 withdraws from the sleeve 11 backward, the distance between the first section 111 and the third section 121 in the first direction perpendicular to the first direction becomes larger, the cross-section of the laminar gap 13 becomes larger, and the flow resistance of the laminar gap 13 becomes smaller.

[0045] The channel 1222 is used to connect the laminar gap 13 and the end of the sleeve 11 away from the laminar gap 13, so that the fluid flowing out of the laminar gap 13 can flow backward stably; it can be understood that the channel 1222 can be opened only on the first section 111, or only on the fourth section 122, or on both the first section 111 and the fourth section 122; optionally, the channel 1222 is a through-hole structure.

[0046] The beneficial effects of this embodiment are as follows: the sleeve 11 and the plunger 12 are screwed together through the internal thread 1121 and the external thread 1221, so that the plunger 12 does not need to be fixed to the sleeve 11 by squeezing the sleeve 11, and the sleeve 11 will not be plastically deformed. Even if the plunger 12 is screwed in too much during assembly in the sleeve 11, the position of the plunger 12 can be readjusted by screwing the plunger 12 out. After an assembly error, the sleeve 11 can continue to be used, thereby reducing the scrap rate of the sleeve 11. At the same time, the coaxial connection between the internal thread 1121 and the external thread 1221 makes the sleeve 11 and the plunger 12 The higher coaxiality makes the laminar gap 13 more uniform and the laminar state more stable, ensuring that the pressure difference and flow characteristics of the flow channel in the flow channel area along the flow direction are evenly distributed in the annular direction, effectively improving the flow resistance linearity of the laminar flow element; the channel 1222 can be set to ensure that the fluid continues to flow after flowing out of the laminar gap 13 on the basis of the threaded connection, thereby ensuring the stability of the laminar flow element 10; the plunger 12 and the sleeve 11 are threadedly connected, and the position can be adjusted by rotating the plunger 12, thereby adjusting the flow resistance of the laminar gap 13, so that the laminar flow element 10 can provide different flow resistances according to different usage scenarios.

[0047] In some embodiments, Figure 1As shown, the first section 111 has an inner conical surface 1111 extending along the first direction, and the third section 121 has an outer conical surface 1211. The inner conical surface 1111 and the outer conical surface 1211 are coaxially arranged, and the outer conical surface 1211 and the inner conical surface 1111 form a laminar flow gap 13.

[0048] The diameters of the inner conical surface 1111 and the outer conical surface 1211 gradually decrease from the third section 121 to the fourth section 122; it can be understood that the inner conical surface 1111 and the outer conical surface 1211 can be set to the same slope or different slopes.

[0049] The beneficial effects of this embodiment are as follows: the coaxial outer cone surface 1211 and the inner cone surface 1111 form a laminar flow gap 13, so that the cross-sectional area of ​​the laminar flow gap 13 changes more evenly, the flow resistance changes more evenly, and the laminar flow state is more stable.

[0050] In some embodiments, the sleeve 11 and the plunger 12 are fixedly connected at the connection between the external thread 1221 and the internal thread 1121 .

[0051] After the plunger 12 is adjusted to a suitable position in the sleeve 11, the sleeve 11 and the plunger 12 are fixedly connected at the connection between the external thread 1221 and the internal thread 1121. Optionally, the connection method is electric welding or laser welding.

[0052] The beneficial effects of this embodiment are: fixing the sleeve 11 and the plunger 12 to avoid shaking after the sleeve 11 and the plunger 12 are screwed together, which can ensure the stability of the assembly and make the flow resistance of the laminar flow element 10 more stable; fixing at the connection between the external thread 1221 and the internal thread 1121 can avoid affecting the fluid in the channel 1222.

[0053] In some embodiments, Figure 1 , Figure 2 As shown, the fourth section 122 is a cylindrical structure; a plurality of channels 1222 are provided and the channels 1222 are grooves, and the channels 1222 are provided on the outer peripheral surface of the fourth section 122 and at least one of the inner surfaces of the second section 112; a plurality of sections of the external thread 1221 are provided, and the plurality of sections of the external thread 1221 and the plurality of channels 1222 are alternately arranged around the first direction.

[0054] One end of each channel 1222 away from the laminar gap 13 in the first direction is flush with one end of the fourth section 122 away from the third section 121; optionally, the channels 1222 all extend along the first direction to allow the fluid to flow stably along the first direction.

[0055] A channel 1222 is formed between two adjacent sections of the external thread 1221 , and fluid flows from the laminar gap 13 into the channel 1222 ; optionally, the external thread 1221 is provided with at least three sections to ensure the coaxiality and stability of the connection between the plunger 12 and the sleeve 11 .

[0056] The beneficial effects of this embodiment are as follows: multiple channels 1222 and external threads 1221 are alternately arranged, so that the multiple external threads 1221 are spaced apart around the first direction, so that the sleeve 11 and the plunger 12 are threadedly connected at multiple positions, and the connection between the sleeve 11 and the plunger 12 is more stable; at the same time, the multiple channels 1222 are spaced apart around the first direction, so that the fluid at different positions at the end of the laminar gap 13 can be dispersed into the channels 1222 and flow backward, thereby reducing flow resistance and making the fluid flow more stable.

[0057] In some embodiments, Figure 2 , Figure 3 As shown, the sum of the central angles A of the multiple channels 1222 around the first direction is greater than 180°; the sum of the central angles A of all the channels 1222 around the first direction is greater than the sum of the central angles B of all the external threads 1221 around the first direction.

[0058] The beneficial effect of this embodiment is that the sum of the central angles of the multiple channels 1222 around the first direction is greater than 180°, and the flow resistance is reduced by limiting the minimum range of the channels 1222, so that the fluid flows more stably in the channels 1222.

[0059] In some embodiments, the plurality of channels 1222 are arranged at equal intervals around the first direction, that is, the distance between any two adjacent channels 1222 in the circumferential direction around the first direction is equal.

[0060] The beneficial effects of this embodiment are as follows: the multiple channels 1222 are arranged at equal intervals around the first direction, so that the distribution of the channels 1222 is more uniform, the flow resistance distribution is more uniform, the fluid flow state at different positions is more consistent, and the fluid flow is more stable.

[0061] In some embodiments, the cross-sectional areas of the plurality of channels 1222 are all equal, that is, the cross-sectional areas of all channels 1222 are equal at every position along the first direction.

[0062] The beneficial effect of this embodiment is that the cross-sectional areas of the multiple channels 1222 are equal, so the flow resistance of the channels 1222 is more consistent, making the flow state of the fluid in different channels 1222 more consistent, and making the fluid flow more stable.

[0063] In some embodiments, Figure 2 As shown, the end of the channel 1222 is flush with the end of the third section 121 , that is, one end of the channel 1222 is directly connected to the laminar flow gap 13 .

[0064] The beneficial effect of this embodiment is: when the third section 121 has an outer cone 1211 and a part of the outer cone 1211 is located in the second section 112, the change in the gap between the outer cone 1211 and the second section 112 is inconsistent with the change in the laminar gap 13, and the channel 1222 is set to be flush with the end of the third section 121, so that the channel 1222 is directly connected to the laminar gap 13, avoiding the fluid from flowing through a distance between the outer cone 1211 and the second section 112 before entering the channel 1222, so that the fluid in the laminar gap 13 can directly enter the channel 1222, making the fluid flow more stable.

[0065] In some embodiments, Figure 1 As shown, the sleeve 11 is provided with a first flow channel hole 113 and a second flow channel hole 114 at two ends along the first direction, respectively. The first flow channel hole 113 and the second flow channel hole 114 are connected to the inside and outside of the sleeve 11 .

[0066] Optionally, the first section 111 includes a cylindrical structure, the cylindrical structure does not enclose the laminar gap 13 with the third section 121, the cylindrical structure is arranged at one end of the inner cone 1111 away from the second section 112, and the inner diameter of the cylindrical structure is equal to the maximum inner diameter of the inner cone 1111; the first flow channel hole 113 is arranged on the cylindrical structure, and the second flow channel hole 114 is arranged on the second section 112. The plunger 12 is arranged between the first flow channel hole 113 and the second flow channel hole 114, and the first flow channel hole 113 and the laminar gap 13 divide the fluid, a part of the fluid flows out of the sleeve 11 from the first flow channel hole 113, and the other part of the fluid flows into the laminar gap 13; the fluid flowing out of the first flow channel hole 113 finally flows into the sleeve 11 from the second flow channel hole 114.

[0067] The beneficial effects of this embodiment are as follows: the first flow channel hole 113 and the second flow channel hole 114 are provided to facilitate the connection between the laminar flow element 10 and the diversion pipe 20, and to facilitate the use of the laminar flow element 10 during diversion.

[0068] In other embodiments, a rotation groove is provided at at least one of the two ends of the plunger 12 along the first direction, the rotation groove extends along the first direction, and the cross-section of the rotation groove is a polygon; the rotation groove is used to engage with tools such as a screwdriver or a wrench; optionally, the rotation groove is a cross groove, a hexagonal groove or a plum blossom groove.

[0069] The beneficial effects of this embodiment are as follows: the provision of the rotation groove facilitates the use of tools such as a screwdriver or a wrench to drive the plunger 12 to rotate, making the operation more convenient and more labor-saving.

[0070] Please refer to Figures 1 to 3In some embodiments, the laminar flow element 10 includes a sleeve 11 and a plunger 12; the sleeve 11 includes a first section 111 and a second section 112 arranged along a first direction, the first section 111 has an inner conical surface 1111 extending along the first direction, and the inner surface of the second section 112 is provided with an inner thread 1121; the X direction in the figure is the first direction; the plunger 12 is arranged in the sleeve 11; the plunger 12 includes a third section 121 and a fourth section 122 arranged along the first direction; the third section 121 has an outer conical surface 1211; the inner conical surface 1111 is coaxially arranged with the outer conical surface 1211, the diameters of the inner conical surface 1111 and the outer conical surface 1211 gradually decrease from the third section 121 to the fourth section 122, the outer conical surface 1211 and the inner conical surface 1111 form a laminar flow gap 13, and the cross-sectional area of ​​the laminar flow gap 13 gradually decreases along the direction from the third section 121 to the fourth section 122.

[0071] The fourth section 122 is a cylindrical structure, and a plurality of channels 1222 are provided on the outer peripheral surface of the fourth section 122, the channels 1222 are grooves, the channels 1222 extend along the first direction, the channels 1222 are connected to the laminar gap 13, and the channels 1222 are connected to both ends of the sleeve 11 along the first direction; the plurality of channels 1222 are arranged at equal intervals around the first direction and the cross-sectional areas of the plurality of channels 1222 are equal; the end of the channel 1222 is flush with the end of the third section 121.

[0072] The outer circumferential surface of the fourth section 122 is also provided with multiple sections of external threads 1221, which are screwed with the internal threads 1121; the external threads 1221 are provided with multiple sections, and the multiple sections of external threads 1221 and the multiple channels 1222 are alternately arranged around the first direction; the sum of the central angles A of the multiple channels 1222 around the first direction is greater than 180°.

[0073] When in use, the plunger 12 is screwed to the sleeve 11, and the position of the plunger 12 in the sleeve 11 is adjusted by rotating the plunger 12, thereby adjusting the flow resistance of the laminar flow element 10; after the plunger 12 is adjusted to a suitable position in the sleeve 11, the sleeve 11 and the plunger 12 are welded at the connection between the external thread 1221 and the internal thread 1121.

[0074] In a second aspect, the present application also provides a mass flow controller 100, such as Figure 4 , Figure 5 As shown, a laminar flow element 10 including any one of the embodiments of the first aspect.

[0075] Please refer to Figure 1 , Figure 4The mass flow controller 100 also includes a shunt tube 20, the inlet end of the shunt tube 20 is connected to the first flow channel hole 113, and the outlet end of the shunt tube 20 is connected to the second flow channel hole 114; a part of the fluid in the mass flow controller 100 flows into the shunt tube 20 from the first flow channel hole 113, and the other part of the fluid flows into the laminar flow gap 13.

[0076] The beneficial effects of this embodiment are: using the laminar flow element 10 of the first aspect for the mass flow controller 100 can provide a more accurate and stable flow resistance, the total flow rate of the fluid calculated based on the flow resistance of the laminar flow element 10 is more accurate, and the control of the fluid flow rate is also more accurate.

[0077] In some embodiments, the mass flow controller 100 also includes a main body 30, in which an inflow chamber 31, an installation chamber and an outflow chamber 32 extending along a first direction are provided, the sleeve 11 is installed in the installation chamber and the two ends of the sleeve 11 along the first direction are respectively connected to the inflow chamber 31 and the outflow chamber 32; a first flow channel hole 113 is opened on the main body 30 and the two ends of the first flow channel hole 113 are respectively connected to the inlet end of the inlet chamber 31 and the diverter tube 20, and a second flow channel hole 114 is opened on the main body 30 and the two ends of the second flow channel hole 114 are respectively connected to the outflow chamber 32 and the outlet end of the diverter tube 20.

[0078] Optionally, a sealing ring is provided between the sleeve 11 and the inflow chamber 31 , and a sealing ring is provided between the sleeve 11 and the outflow chamber 32 .

[0079] A portion of the fluid in the inflow chamber 31 of the mass flow controller 100 flows into the shunt tube 20 from the first flow channel hole 113 and flows out from the second flow channel hole 114, and another portion of the fluid in the inflow chamber 31 flows into the laminar flow gap 13 and flows out from the channel 1222 of the sleeve 11, and the fluid reconverges in the outflow chamber 32. The mass flow controller 100 calculates the flow rate of the fluid in the shunt tube 20, calculates the total flow rate of the fluid according to the flow resistance ratio between the shunt tube 20 and the laminar flow element 10, and then regulates the flow rate of the fluid through the valve.

[0080] The beneficial effects of this embodiment are as follows: the first flow channel hole 113 and the second flow channel hole 114 are arranged on the main body 30, and when the laminar flow element 10 is connected to the main body 30, there is no need to consider the connection between the diverter tube 20 and the laminar flow element 10, which makes it more convenient to install or replace the laminar flow element 10 in the main body 30.

[0081] Based on the above effects, the mass flow controller of the embodiment of the present application has broad application prospects in achieving high-precision and high-stability flow control; the known and potential technical and product application fields of the mass flow controller of the embodiment of the present application and its specific application methods are exemplified as follows:

[0082] Semiconductor manufacturing: Key steps in the semiconductor manufacturing process, such as chemical vapor deposition (CVD) and physical vapor deposition (PVD), require extremely high gas flow control accuracy; the embodiments of the present application can provide more accurate flow data to ensure the consistency of the semiconductor manufacturing process and the quality of the product.

[0083] Pharmaceutical industry production: In the field of biopharmaceuticals, especially in the process of culturing cells and producing drugs, precise gas control is crucial; the embodiments of the present application can improve the accuracy of gas flow control and ensure the accuracy and safety of drug synthesis.

[0084] Environmental monitoring equipment: In environmental protection fields such as air quality monitoring and water quality testing, it is necessary to continuously and accurately monitor and control the sampling flow; the embodiments of the present application can provide fast response and high-precision flow monitoring, thereby improving the reliability of environmental monitoring.

[0085] Laboratories and scientific research equipment: Scientific research experiments often require precise control and measurement of extremely small gas or liquid flow rates; the technical solution of the embodiments of the present application can provide fine flow control for various laboratories to ensure the accuracy and efficiency of scientific research work.

[0086] Chemical process control: In the field of chemical production and fine chemicals, the precise proportion of controlled fluids directly affects product quality. The technical solution of the embodiment of the present application provides key control parameters for fine chemical processes by providing stable and accurate flow measurement.

[0087] Aerospace and military equipment: In aerospace and military equipment, the accuracy and response time of flow control are critical to the performance of the entire system; the embodiments of the present application can provide the required high-precision flow control in these demanding applications.

[0088] Food and beverage industry: In the production process of food and beverage, the precise amount of gas and liquid added is very important for the taste and quality of the product; the embodiments of the present application can provide high-precision and high-stability flow control in these applications, making the gas and liquid addition more accurate.

[0089] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A laminar flow element, characterized in that: include: A sleeve, the sleeve comprising a first section and a second section arranged along a first direction, the inner surface of the second section being provided with an internal thread; A plunger, wherein the plunger is arranged in the sleeve; the plunger includes a third section and a fourth section arranged along the first direction, the third section and the first section form an annular laminar gap, and the cross-sectional area of ​​the laminar gap gradually decreases along the direction from the third section to the fourth section; at least one of the second section and the fourth section is provided with a channel, the channel extends along the first direction, the channel is connected with the laminar gap, and the channel is connected with both ends of the sleeve along the first direction; the outer surface of the fourth section is provided with an external thread, and the external thread is screwed with the internal thread.

2. The laminar flow element according to claim 1, characterized in that The first section has an inner conical surface extending along the first direction, the third section has an outer conical surface, the inner conical surface is coaxially arranged with the outer conical surface, and the outer conical surface and the inner conical surface enclose the laminar flow gap.

3. The laminar flow element according to claim 1, characterized in that The sleeve and the plunger are fixedly connected at the connection between the external thread and the internal thread.

4. The laminar flow element according to any one of claims 1 to 3, characterized in that The fourth section is a cylindrical structure; the channels are provided in plurality and are grooves, and the channels are provided on at least one of the outer peripheral surface of the fourth section and the inner surface of the second section; the external thread is provided in plurality of sections, and the plurality of sections of the external thread and the plurality of the channels are alternately provided around the first direction.

5. The laminar flow element according to claim 4, characterized in that The sum of the central angles of the plurality of channels around the first direction is greater than 180°.

6. The laminar flow element according to claim 4, characterized in that The plurality of channels are arranged at equal intervals around the first direction.

7. The laminar flow element according to claim 4, characterized in that The cross-sectional areas of the plurality of channels are all equal.

8. The laminar flow element according to claim 4, characterized in that The end of the channel is flush with the end of the third section.

9. The laminar flow element according to claim 1, characterized in that The sleeve is provided with a first flow channel hole and a second flow channel hole at two ends along the first direction, respectively. The first flow channel hole and the second flow channel hole are both connected to the inside and outside of the sleeve.

10. A mass flow controller, characterized in that: The laminar flow element comprises the laminar flow element as claimed in any one of claims 1 to 9.

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