Metal current limiter

Abstract

The invention discloses a metal flow limiter which comprises a shell, a sintered filter element embedded into one end in the shell and a pore plate connected to the front end of the sintered filter element. A hole is formed in the center of the pore plate, a fluid passes through the hole and flows into the sintered filter element, and the pore plate is detachably connected to the front end of the sintered filter element. The pore plate is added into the flow limiter, so that the flow limiting characteristic can be accurately adjusted, the adaptive range is expanded, the flow limiting effect of the filter element is enhanced, meanwhile, designable adjusting parameters are provided for multi-working-condition adaptation, the pore plate can generate a small part of stable pressure drop, the superimposed effect is formed by the pore plate and the pressure drop of the metal sintering filter element, the total flow limiting requirement is jointly met, and the service life of the filter element is prolonged. All pressure drop caused by single dependence on the sintered filter element is avoided, loss of the sintered filter element due to long-term bearing of overhigh pressure difference is reduced, and the service life of the filter element is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flow restrictors, in particular to a metal flow restrictor. BACKGROUND

[0002] As a key fluid control component, flow restrictors are widely used in industries such as chemical industry, gas purification, hydraulic system, semiconductor manufacturing, etc. The core function of flow restrictors is to accurately control the flow or pressure of fluid (gas or liquid) to ensure the stable and safe operation of the system. In particular, in pneumatic components, lubricating oil systems, fuel systems and hydraulic pressure systems, purifying and limiting the flow of medium are crucial links.

[0003] In the prior art, flow restrictors are made of sintered metal porous materials, such as filter cartridges and filter plates made of stainless steel (304, 304L, 316, 316L) or titanium (TA1) metal powder through screening, molding and high-temperature sintering process. Because of their excellent corrosion resistance, high mechanical strength, uniform pore structure and controllable filtration precision (usually in the range of 0.5 μm to 70 μm), they are widely used to manufacture high-performance flow restrictors. Such sintered metal flow restrictors can provide stable porous medium pressure drop, and their flow-pressure difference characteristics can be characterized by experimentally calibrated curves under certain conditions.

[0004] As mentioned in Chinese Patent CN220354200U Semiconductor Process High-Purity Porous Metal Flow Restrictor, sintered filter cartridges are used as core materials for flow restrictors to limit flow and provide stable, reliable and smooth airflow.

[0005] However, in actual application, when adjusting the flow and pressure of fluid according to the calibrated working conditions, the flow restrictor needs to be replaced. However, it becomes cumbersome to choose which type of flow restrictor to use. According to the flow and pressure of the calibrated working conditions, experimental or simulation analysis is needed to obtain the accurate type, and then the flow restrictor needs to be replaced, which is a heavy workload.

[0006] In addition, in order to cope with various calibrated working conditions, multiple types of flow restrictors and sintered filter cartridges need to be prepared. Even if the flow and pressure working conditions change slightly, flow restrictors and sintered filter cartridges of specific types are needed, which is too costly.

[0007] Therefore, it is necessary to optimize the flow restrictor in the prior art to solve the above problems. SUMMARY

[0008] The purpose of the present application is to disclose a metal flow restrictor, which only needs to adjust the size of the orifice plate inside the flow restrictor to meet the requirements of flow and pressure under different working conditions, reducing the replacement cost of sintered filter cartridges.

[0009] In order to achieve the above object, the application provides a metal current limiter, comprising a shell, a sintered filter element embedded in one end of the shell, and a hole plate connected to the front end of the sintered filter element; a hole is formed in the center of the hole plate for fluid to pass through and flow into the sintered filter element.

[0010] In some embodiments, the hole plate is detachably connected to the front end of the sintered filter element.

[0011] In some embodiments, the ratio of the hole diameter of the hole plate to the diameter of the hole plate is 0.075-0.75.

[0012] In some embodiments, a sealing ring is sleeved on the outer side of the hole plate, and the sealing ring is clamped between the outer side of the hole plate and the inner wall of the shell.

[0013] In some embodiments, a boss is arranged on the inner wall of one end of the shell, and the hole plate is embedded in the boss and connected to the front end of the sintered filter element.

[0014] In some embodiments, a first thread is formed on the outer side of the hole plate, and a second thread that engages with the first thread is formed on the side wall of the boss for connecting the hole plate.

[0015] In some embodiments, a laterally movable buckle is arranged on the outer side of the hole plate, and a buckle groove that can accommodate the buckle is arranged on the side wall of the boss, and the buckle groove and the buckle can form a locking structure.

[0016] In some embodiments, a laterally movable buckle is arranged on the side wall of the boss, and a buckle groove that can accommodate the buckle is arranged on the outer side of the hole plate, and the buckle groove and the buckle can form a locking structure.

[0017] In some embodiments, the buckle can extend out of the side wall of the boss, one side of the lower end of the buckle is provided with a spring, and the other side of the lower end of the buckle extends out of the outer wall of the shell, and pulling the lower end of the buckle can drive the buckle to move laterally.

[0018] In some embodiments, one end of the buckle can extend out of the side wall of the boss, the inside of the buckle is provided with a spring, a vertical slot is formed in the end of the shell, a pressing device is arranged in the vertical slot, and the pressing device moves up and down and drives the buckle to move laterally.

[0019] In some embodiments, the lower end of the pressing device is provided with a first inclined surface, the other end of the buckle is provided with a first inclined platform, the inclined platform is provided with a second inclined surface that cooperates with the first inclined surface, and the pressing device moves up and down and drives the buckle to move laterally.

[0020] In some embodiments, a third thread is formed on the outer side of the pressing device, and a fourth thread that engages with the third thread is formed in the vertical slot for limiting the up and down movement of the pressing device in the vertical slot.

[0021] Compared with the prior art, the beneficial effects of the present application are: (1) the orifice plate can precisely adjust the flow limiting characteristics, expand the adaptation range, and strengthen the flow limiting effect of the filter element, while providing designable adjustment parameters for multi-working condition adaptation; (2) the orifice plate itself can generate a small stable pressure drop, and the pressure drop of the metal sintered filter element forms a superposition effect, together bearing the total flow limiting demand; (3) the orifice plate can adjust the gas flow rate and strengthen the flow limiting capacity of the filter element, and the orifice diameter of the orifice plate directly determines the gas flow rate. By reducing the orifice diameter, the gas accelerates after passing through the orifice plate and enters the filter element at a high flow rate. The high flow rate gas diffuses at the front end of the sintered filter element, so that the actual pressure drop of the sintered filter element is much larger than the inherent pressure drop when working alone, greatly improving the overall flow limiting effect and realizing more stringent flow control. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a schematic diagram of the metal flow limiter structure in the prior art;

[0023] Figure 2 It is a schematic diagram of the metal flow limiter structure shown in the present application;

[0024] Figure 3 It is a schematic diagram of the metal flow limiter structure shown in Example 2;

[0025] Figure 4 It is a schematic diagram of the metal flow limiter structure shown in Example 3;

[0026] Figure 5 It is a schematic diagram of the metal flow limiter structure shown in Example 4;

[0027] Figure 6 It is a schematic diagram of the metal flow limiter structure shown in Example 5

[0028] Figure 7 It is a schematic diagram of the metal flow limiter structure shown in Example 6;

[0029] Figure 8 It is a partial enlarged view of A in Example 6;

[0030] Figure 9 It is a velocity distribution cloud diagram of the flow limiter without and with an orifice plate of model N30P30000;

[0031] Figure 10 It is a flow rate pressure difference curve diagram of the flow limiter without and with an orifice plate of model N30P30000C;

[0032] Figure 11 It is a flow rate pressure difference curve diagram of the flow limiter without and with an orifice plate of model N30P40000C

[0033] Figure 12The graphs show the velocity-pressure difference curves for the N30P45000 flow limiter with and without an orifice plate. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings. However, it should be noted that these embodiments are not intended to limit the present invention. Equivalent changes or substitutions in function, method, or structure made by those skilled in the art based on these embodiments are all within the scope of protection of the present invention.

[0035] like Figure 1 As shown, in the prior art, a metal flow limiter includes a housing 2, a sleeve 3 connected inside the housing 2, and a sintered filter element 4 connected inside the sleeve 3. One end of the housing 2 is provided with a first step 21 and extends inward to form a first groove 20, and the other end of the housing 2 is formed with a first through hole 22 communicating with the first groove 20. The diameter of the first groove 20 is larger than the diameter of the first through hole 22.

[0036] One end of the sleeve 3 has a second step 31 that extends inward to form a second groove 30. The other end of the sleeve 3 has a second through hole 32 that communicates with the second groove 30. The diameter of the second groove 30 is larger than the diameter of the second through hole 32. The second through hole 32 communicates with the first through hole 22.

[0037] The sleeve 3 is located within the first groove 20, and the sleeve 3 and the housing 2 are press-fitted together for a tight connection. The sintered filter element 4 is located within the second groove 30, and the sintered filter element 4 and the sleeve 3 are press-fitted together for a tight connection.

[0038] The sintered filter element 4 is porous, allowing airflow to pass evenly through hundreds of microchannels without increasing flow velocity or creating irregular flow paths. It is less prone to blockage and turbulence, reducing wear and significantly improving the reliability and stability of the flow restrictor, thus ensuring the smoothness and constancy of the airflow.

[0039] Compared with the prior art, the metal flow limiter disclosed in this invention no longer has a sleeve 3 structure, and the sintered filter element 4 is directly interference-fitted and installed at one end of the housing 2.

[0040] Example 1

[0041] like Figure 2 As shown, compared with the prior art, the housing 2 in this embodiment is further provided with a perforated plate 5 at one end, which is embedded in the front end of the sintered filter element 4. The perforated plate 5 has a hole 50 in the center for fluid to pass through and flow into the sintered filter element 4. At this time, the first through hole 22 is connected to the hole 50.

[0042] The metal flow restrictor shown in the application, the center hole diameter (d) of the orifice plate is in the range of the relationship with the diameter (D) of the orifice plate: d / D=0.075-0.75, the smaller the value of d / D, the stronger the flow limiting effect of the orifice plate, the larger the value of d / D, the weaker the flow limiting effect. When the value is less than 0.075, the hole diameter is too small, and the airflow will produce serious separation and vortex before and after the orifice plate, causing the pressure drop to fluctuate too much, and the high-speed airflow will impact and damage the front end of the sintered filter element. When the value is greater than 0.75, the orifice plate cannot provide effective pressure drop, and the flow limiting effect is limited.

[0043] Example 2

[0044] As Figure 3 shown, the difference from example 1 is that the orifice plate 5 is detachably connected to the front end of the sintered filter element 4. The sintered filter element 4 is embedded in the shell 2, and a boss 6 is provided on the inner wall of the shell 2 above the sintered filter element 4, which has a diameter larger than that of the sintered filter element 4, for placing the orifice plate 5.

[0045] The orifice plate 5 is sleeved with a sealing ring 7 on the outside, and the sealing ring 7 is clamped between the outer side of the orifice plate 5 and the side wall of the boss 6 (i.e. the inner wall of the shell 2).

[0046] According to actual use, when the sealing ring 7 is used to detachably connect the orifice plate 5, the boss 6 can also not be provided on the inner wall of the shell 2.

[0047] Example 3

[0048] As Figure 4 shown, the difference from example 2 is that the boss 6 is provided on the inner wall of the shell 2, and the orifice plate 5 is embedded in the boss 6 and connected to the front end of the sintered filter element 4. A first thread 51 is provided on the outer side of the orifice plate 5, and a second thread 61 is provided on the side wall of the boss 6, which is engaged with the first thread 51, for connecting the orifice plate 5.

[0049] Example 4

[0050] The difference from example 2 is that the boss 6 is provided on the inner wall of the shell 2, and the orifice plate 5 is embedded in the boss 6 and connected to the front end of the sintered filter element 4.

[0051] A clamping groove or a laterally movable clasp is provided on the side wall of the boss 6, and a laterally movable clasp or a clamping groove is provided on the outer side of the orifice plate 5, and the clamping groove and the clasp form a locking structure.

[0052] In this embodiment, a clamping groove 9 is provided on the side wall of the boss 6 of the flow restrictor, and a laterally movable clasp 8 is provided on the outer side of the orifice plate 5, and the clamping groove 9 and the clasp 8 are used together to form a locking structure.

[0053] As Figure 5As shown, the outer side of the perforated plate 5 is provided with symmetrically arranged grooves 82. The buckle 8 is movably connected in the groove 82. A spring 81 is provided in the groove 82. One end of the spring 81 is fixedly connected to the groove 82, and the other end of the spring 81 is connected to the buckle 8. The buckle 8 can move laterally in the groove 81 as the spring 81 extends and retracts. When the buckle 8 is squeezed, the buckle 8 retracts into the perforated plate 5. After the squeeze is released, the buckle 8 pops out.

[0054] To ensure a better fit between the buckle 8 and the slot 9, the end of the buckle 8 has a first arc-shaped surface, and the slot 9 has a second arc-shaped surface that engages with the first arc-shaped surface. When installing the perforated plate 5, pressing it downwards causes the buckle 8 to first contract and then spring into the slot 9 due to the sliding engagement of the first and second arc-shaped surfaces, forming a locking fit. For replacement, simply remove the perforated plate 5.

[0055] In addition, the buckle 8 can also be arranged in a ring.

[0056] Example 5

[0057] The difference from Embodiment 4 is that in this embodiment, the side wall of the boss 6 is provided with a buckle 11 that can move laterally, and the outer side of the perforated plate 5 is provided with a slot 10 that can accommodate the buckle 11. The slot 10 and the buckle 11 together form a locking structure.

[0058] like Figure 6 As shown, the buckle 11 includes a buckle end 13 and a buckle lower end body 12. A spring is fitted on the buckle lower end body 12. The buckle end 13 can move laterally and extend out of the side wall of the boss 6 (i.e., the inner wall of the housing 2). One end of the buckle lower end body 12 can move out of the outer wall of the housing 2. Pulling the buckle lower end body 12 can drive the buckle end 13 to move laterally. One end of the spring is connected to the buckle lower end body 12, and the other end of the spring is connected to the inner wall of the housing 2. Under the action of the spring, the buckle 11 can move laterally.

[0059] In use, pulling down the lower body 12 of the buckle retracts the buckle end 13 into the side wall of the boss 6 (i.e., the inner wall of the housing 2), placing the perforated plate 5 onto the boss 6. Then, releasing the lower body 12 of the buckle causes the buckle end 13 to insert into the slot 10 on the perforated plate 5 under the action of the spring, forming a locked state. When it is necessary to disassemble and replace the perforated plate 5, simply pulling down the lower body 12 of the buckle removes the perforated plate 5, completing the replacement, which is convenient for operation.

[0060] It should be noted that in this embodiment, the spring is always in a stretched state.

[0061] Example 6

[0062] The difference from Example 5 is that, as Figures 7-8As shown, the boss 6 side wall is provided with a transversely movable buckle 14, one end of the buckle 14 extends out of the boss 6 side wall (i.e. the inner wall of the shell 2), the buckle 14 is provided with a spring, one end of the spring abuts the inner groove of the buckle 14, and the other end of the spring abuts the shell 2. Figure 8 As shown, the buckle 14 is provided with an inner groove for accommodating the spring, and the spring placed in the inner groove can drive the buckle 14 to move transversely.

[0063] The upper end of the shell 2 is provided with a vertical groove 23, the vertical groove 23 is provided with a pressing device 15, the outer side of the pressing device 15 is provided with a third screw thread 152, the vertical groove 23 is provided with a fourth screw thread 231 engaged with the third screw thread 152, for limiting the pressing device 15 to move up and down in the vertical groove 23.

[0064] One end of the pressing device 15 extends out of the top end of the shell 2, and the other end of the pressing device 15 is provided with a first inclined surface 151. The other end of the buckle 14 is provided with a first inclined platform 16, the inclined platform 16 is provided with a second inclined surface 161 matched with the first inclined surface 151, and the pressing device 15 moves downward to drive the buckle 14 to move transversely.

[0065] In use, the pressing device 15 is rotated to drive the buckle 14 to retract into the shell 2, the hole plate 5 is placed on the boss 6, the pressing device 15 is released, and the buckle 14 is reset and locked with the slot 10. When it is necessary to disassemble and replace the hole plate 5, the hole plate 5 can be taken out by rotating the pressing device 15 again, and the replacement is completed.

[0066] I. Simulation analysis test

[0067] Under the same flow condition, the ANSYS simulation software is used to simulate and analyze the gas flow limiting of the metal flow restrictor, the F-TC type N30P30000 Flores flow restrictor (standard flow 30000sccm) is selected, and the porosity of the flow restrictor is 47.5%. As shown in the figure, Figure 9 The left side is a flow restrictor without a hole plate structure, and the right side is a flow restrictor with a hole plate structure. Under the same gas inlet condition, the flow limiting effect of the flow restrictor with the hole plate structure is more obvious, and the gas flow rate decreases more.

[0068] II. Flow rate pressure difference test

[0069] Three types of Flores flow restrictors are selected in the application, the types are N30P30000C, N30P40000C and N30P45000, and a 1mm center hole is selected. Figures 10-12 As shown in the figure, under the same flow rate, the pressure difference of the flow restrictor with the hole plate is higher than that of the flow restrictor without the hole plate, and the flow limiting effect is more obvious.

[0070] The metal current limiter disclosed in the application can precisely adjust the current limiting characteristics, expand the adaptation range, strengthen the current limiting effect of the filter element, and provide designable adjustment parameters for multi-working condition adaptation. The orifice plate itself can generate a stable small pressure drop, and the pressure drop of the metal sintered filter element forms a superposition effect, which together bears the total current limiting demand, avoids relying on the sintered filter element to generate all the pressure drop, reduces the loss of the sintered filter element caused by long-term bearing of the excessively high pressure difference, and prolongs the service life of the filter element.

[0071] The orifice plate can also adjust the gas flow rate and strengthen the current limiting capacity of the sintered filter element. The orifice diameter of the orifice plate directly determines the gas flow rate. By reducing the orifice diameter, the gas accelerates after passing through the orifice plate and enters the sintered filter element at a high flow rate. The high flow rate gas diffuses at the front end of the sintered filter element, so that the actual pressure drop of the sintered filter element is much larger than the inherent pressure drop when working alone, greatly improves the overall current limiting effect, and realizes more strict flow control.

[0072] In addition, the orifice plate can expand the current limiting adjustment range and adapt to multi-working condition requirements. Since the current limiting range of the metal sintered filter element alone is determined by the pore structure itself and is relatively fixed, the orifice diameter of the orifice plate can be flexibly adjusted. By replacing the orifice plate with different orifice diameters, different flow rates and pressure differentials can be quickly adapted without replacing the core metal sintered filter element, thereby reducing the equipment replacement cost.

[0073] The series of detailed descriptions listed above are only specific descriptions of the feasible implementation manners of the application, and are not used to limit the protection scope of the application. Equivalent implementation manners or changes made without departing from the spirit of the application should be included in the protection scope of the application.

[0074] In addition, it should be understood that although the present specification is described in terms of embodiments, each embodiment does not contain only one independent technical solution. The description manner of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A metal current limiter, characterized by, The application relates to a filter, which comprises a shell, a sintered filter element embedded into one end of the shell, and a hole plate connected to the front end of the sintered filter element.

2. The metal current limiter of claim 1, wherein The hole plate is detachably connected to the front end of the sintered filter element.

3. The metal current limiter of claim 2, wherein, The ratio of the hole diameter of the hole plate to the diameter of the hole plate is 0.075-0.

75.

4. The metal current limiter of claim 2, wherein, The hole plate is provided with a sealing ring on the outer side, which is clamped between the outer side of the hole plate and the inner wall of the shell.

5. The metal current limiter of claim 2, wherein, The inner wall of one end of the shell is provided with a boss, and the hole plate is embedded into the boss and connected to the front end of the sintered filter element.

6. The metal current limiter of claim 5, wherein, The outer side of the hole plate is provided with a first screw thread, and the side wall of the boss is provided with a second screw thread which is engaged with the first screw thread and used for connecting the hole plate.

7. The metal current limiter of claim 5, wherein, The outer side of the hole plate is provided with a laterally movable buckle, and the side wall of the boss is provided with a buckle slot which can accommodate the buckle, and the buckle slot and the buckle can form a locking structure.

8. The metal current limiter of claim 5, wherein, The side wall of the boss is provided with a laterally movable buckle, and the outer side of the hole plate is provided with a buckle slot which can accommodate the buckle, and the buckle slot and the buckle can form a locking structure.

9. The metal current limiter of claim 8, wherein, The buckle can extend out of the side wall of the boss, one side of the lower end of the buckle is provided with a spring, and the other side of the lower end of the buckle extends out of the outer wall of the shell; the lower end of the buckle can be pulled to drive the buckle to move laterally.

10. The metal current limiter of claim 8, wherein, One end of the buckle can extend out of the side wall of the boss, the inside of the buckle is provided with a spring, the end of the shell is provided with a vertical slot, the vertical slot is provided with a pressing device, the pressing device moves up and down to drive the buckle to move laterally.

11. The metal current limiter of claim 10, wherein, The lower end of the pressing device is provided with a first inclined surface, the other end of the buckle is provided with a first inclined platform, the inclined platform is provided with a second inclined surface which is matched with the first inclined surface, and the pressing device moves up and down to drive the buckle to move laterally.

12. The metal current limiter of claim 11, wherein, The outer side of the pressing device is provided with a third screw thread, and the vertical slot is provided with a fourth screw thread which is engaged with the third screw thread and used for limiting the up-and-down movement of the pressing device in the vertical slot.

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