Magnetic liquid level measuring device for ultrapure water

Abstract

The utility model belongs to the technical field of semiconductor production, concretely relates to a magnetic liquid level measuring device for ultrapure water, including sealed container, the position -limited guide component of setting in sealed container inside, the liquid level response subassembly of sliding sleeve setting on the position -limited guide component, the signal receiving piece of setting in sealed container outside, the position -limited guide component includes guide shaft and the sleeve of sleeve setting in the outside of guide shaft, and the signal receiving piece includes a plurality of array formula setting's dry reed. The utility model's magnetic liquid level measuring device for ultrapure water adopts guide shaft and sleeve cooperation, avoids the liquid level response subassembly jam problem, and the magnetic field direction and size of liquid level response subassembly all keep invariant, adopts array formula dry reed to set up in sealed container outside, avoids the pollution inside liquid, has guaranteed the accuracy of liquid level measurement, and the adaptability of overall structure is strong, and the service life is long.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing technology, and specifically to a magnetic liquid level measuring device for ultrapure water. Background Technology

[0002] In advanced manufacturing processes such as semiconductor etching, precise control and measurement of water vapor are required, which places extremely stringent demands on the level measurement device of the water vapor supply source (such as an ultrapure water container). It must not only ensure the accuracy and stability of the measurement, but also meet the ultra-high cleanliness, high-temperature resistance, and anti-contamination characteristics necessary for semiconductor production.

[0003] However, existing magnetic level gauges typically use 304 or 316 stainless steel as the material for components in contact with the liquid. In environments where these gauges are immersed in ultrapure water for extended periods, these materials continuously release metal ions into the water. Simultaneously, their seals may release organic matter, becoming unacceptable sources of contamination. Furthermore, the friction between the float and the guide structure generates metal particles that can directly enter the ultrapure water, catastrophically impacting chip yield. In addition, to ensure the purity of the ultrapure water, the container must be a closed structure, thus employing a built-in magnetic float. When the internal fluid fluctuates or the equipment vibrates, the float is prone to lateral swaying or rotation, causing disorder in the magnetic field direction of the internal magnets. This weakens the magnetic coupling with the external indicator, resulting in problems such as inconsistent indication and flickering. Existing technologies often use dual guide shafts on both sides of the float to suppress swaying. However, when the liquid level in the container is tilted or there is trace crystallization, the dual-shaft structure, due to its small gap, is more prone to jamming, causing the float to fail to accurately reflect the liquid level and leading to measurement failure.

[0004] Therefore, it is necessary to provide a new magnetic level measurement device for ultrapure water. Utility Model Content

[0005] In view of this, the present invention provides a magnetic liquid level measuring device for ultrapure water, which adopts a guide shaft and a sleeve to avoid the problem of jamming of the liquid level sensing component. The direction and magnitude of the magnetic field of the liquid level sensing component remain unchanged. An array of reed switches is set outside the sealed container to avoid contaminating the internal liquid, thus ensuring the accuracy of liquid level measurement. The overall structure has strong adaptability and long service life.

[0006] The technical solution adopted by this utility model to solve its technical problem is: a magnetic liquid level measuring device for ultrapure water is provided, including: a sealed container, a limiting guide assembly disposed inside the sealed container, a liquid level sensing assembly slidably sleeved on the limiting guide assembly, and a signal receiver disposed outside the sealed container. The limiting guide assembly includes a guide shaft and a sleeve sleeved outside the guide shaft. The signal receiver includes a plurality of arrayed reed switches.

[0007] Furthermore, the inner wall of the sealed container is made of pure titanium.

[0008] Furthermore, the limiting guide assembly also includes a fixing plate disposed on the sealed container, the fixing plate being made of pure titanium material and fixed to the inner wall of the sealed container.

[0009] Furthermore, one end of the guide shaft is vertically fixed at the center of the fixed plate, and the axial direction of the guide shaft is consistent with the height direction of the sealed container.

[0010] Furthermore, the sleeve is made of perfluoroalkoxyalkane, the inner diameter of the sleeve matches the diameter of the guide shaft, the sleeve is sleeved on the outside of the guide shaft, and the sleeve is tightly fitted to the guide shaft.

[0011] Furthermore, the liquid level sensing component includes a float sleeved on the outside of the sleeve and a magnet disposed inside the float.

[0012] Furthermore, the float is a hollow ring and is made of pure titanium.

[0013] Furthermore, a cylindrical through hole is formed at the center of the float, the diameter of which matches the outer surface of the sleeve, and a sliding fit is formed between the through hole and the sleeve outside the guide shaft.

[0014] Furthermore, the magnet is in the shape of a ring, and the magnet is a thermal radiation ring with an outer N pole and an inner S pole, and the magnetic field polarity of the magnet is distributed radially.

[0015] Furthermore, the reed switches are disposed outside the sealed container, and a plurality of the reed switches are evenly arranged along the height direction of the sealed container.

[0016] The beneficial effects of this utility model are as follows: The magnetic liquid level measuring device for ultrapure water of this utility model adopts a guide shaft and sleeve in combination, avoiding the problem of jamming of the liquid level sensing component, ensuring long-term operational reliability. The direction and magnitude of the magnetic field of the liquid level sensing component remain unchanged, effectively solving the problem of magnetic field disorder caused by float rotation, providing a stable and reliable trigger signal for the external signal receiver, and ensuring the accuracy and continuity of liquid level measurement. An array of reed switches is used as an external signal receiver, replacing the traditional magnetic flip plate. The reed switches are set outside the sealed container and do not come into contact with ultrapure water, eliminating the risk of contamination. At the same time, the liquid level is determined by detecting the on / off state of the reed switches at different heights, fundamentally solving the problems of chaotic and flickering indication by the magnetic flip plate. The device has a simple structural design, reliable connection of each component, and can adapt to the high-temperature working conditions of ultrapure water heating to generate water vapor. It has strong environmental adaptability and a long service life. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] Figure 1 This is a schematic diagram of the structure of the magnetic liquid level measuring device provided in this embodiment of the utility model; Figure 2 This is a cross-sectional view of the magnetic liquid level measuring device provided in this embodiment of the utility model; Figure 3 This is a schematic diagram of the structure of the liquid level sensing component provided in this embodiment of the utility model; Figure 4 This is a cross-sectional view of the liquid level sensing component provided in this embodiment of the present invention.

[0019] The component names and their numbers in the diagram are as follows: Magnetic liquid level measuring device 100; Sealed container 1; Limiting and guiding assembly 2, fixing plate 21, guide shaft 22, sleeve 23; Liquid level sensing component 3, float 31, through hole 311, support part 312, magnet 32; Signal receiver 4, reed switch 41. Detailed Implementation

[0020] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0021] It should be noted that when a component is referred to as "connected to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0023] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0024] Throughout this specification, reference to "an embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of this application. Therefore, the phrases "in one embodiment," "in some embodiments," or "in some of these embodiments" appear in various places throughout the specification, and not all refer to the same embodiment. Furthermore, in one or more embodiments, a particular feature, structure, or characteristic may be combined in any suitable manner.

[0025] like Figure 1 , Figure 2 As shown, this embodiment provides a magnetic liquid level measuring device 100 for ultrapure water, including a sealed container 1, a limiting guide assembly 2 disposed inside the sealed container 1, a liquid level sensing assembly 3 slidably sleeved on the limiting guide assembly 2, and a signal receiver 4 disposed outside the sealed container 1. The sealed container 1 is used to store ultrapure water. The limiting guide assembly 2 is used to constrain the movement trajectory of the liquid level sensing assembly 3, ensuring that the liquid level sensing assembly 3 stably follows changes in liquid level. The liquid level sensing assembly 3 is used to directly sense the liquid level height of the ultrapure water and generate a magnetic signal. The signal receiver 4 is used to receive the magnetic signal generated by the liquid level sensing assembly 3 and convert it into a liquid level height for display.

[0026] In some embodiments, the sealed container 1 is generally a closed square, and its contents are used to store and hold ultrapure water. The inner wall of the sealed container 1 is made of pure titanium, which allows for the formation of an extremely stable and dense titanium oxide passivation film on the inner wall, thereby preventing the sealed container 1 from reacting with the ultrapure water. The limiting guide component 2 and the liquid level sensing component 3 are both disposed on the inner wall of the sealed container 1, and the signal receiver 4 is disposed on the outer surface of the sealed container 1. The sealed container 1 is also provided with inlet and outlet valves for introducing ultrapure water into the container and discharging water vapor.

[0027] In some embodiments, the limiting guide assembly 2 includes a fixing plate 21 disposed on the sealed container 1, a guide shaft 22 fixedly connected to the fixing plate 21, and a sleeve 23 sleeved on the outside of the guide shaft 22. The fixing plate 21 is made of pure titanium material and is fixed to the inner wall of the sealed container 1 by welding, thereby forming a stable rigid connection with the sealed container 1. The fixing plate 21 is used to provide a stable fixed base for the guide shaft 22, preventing the guide shaft 22 from tilting or shifting due to the lack of a fixed reference, and preventing the liquid level sensing assembly 3 from lateral swinging or rotating due to misalignment of the guide shaft 22. The guide shaft 22 is made of titanium alloy and has a cylindrical structure. One end of the guide shaft 22 is vertically fixed to the center of the fixing plate 21 by welding, and the axial direction of the guide shaft 22 is consistent with the height direction of the sealed container 1, and the height of the guide shaft 22 matches the internal height of the sealed container 1. The guide shaft 22 is used to constrain the movement trajectory of the liquid level sensing component 3, providing a stable sliding track for the liquid level sensing component 3. This ensures that the liquid level sensing component 3 moves accurately and synchronously with changes in liquid level, preventing lateral swaying or rotation caused by liquid fluctuations and external factors, and avoiding disorder in the magnetic field direction of the magnet inside the liquid level sensing component 3. The sleeve 23 is made of perfluoroalkoxyalkane (PFA material), which has strong anti-adhesion properties, excellent wear resistance, and a low coefficient of friction. This makes the surface non-stick to ultrapure water, able to withstand frequent sliding friction of the liquid level sensing component 3, not easily worn or peeled off, and reduces the movement resistance between the sleeve 23 and the liquid level sensing component 3. The inner diameter of the sleeve 23 matches the diameter of the guide shaft 22. The sleeve 23 is fitted on the outside of the guide shaft 22, and the sleeve 23 fits tightly against the guide shaft 22, so that there is no relative displacement between the sleeve 23 and the guide shaft 22. The sleeve 23 can reduce the friction between the liquid level sensing component 3 and the guide shaft 22, prevent dirt from adhering, and isolate the guide shaft 22 from direct contact with the liquid level sensing component 3, ensuring the smooth movement of the liquid level sensing component 3 and the overall cleanliness.

[0028] In some of these embodiments, such as Figure 3 , Figure 4As shown, the liquid level sensing component 3 includes a float 31 sleeved on the outside of the sleeve 23 and a magnet 32 ​​disposed inside the float 31. The float 31 is roughly hollow and annular in shape, and is made of pure titanium. A cylindrical through hole 311 is formed in the center of the float 31. The diameter of the through hole 311 matches the outer surface of the sleeve 23. The through hole 311 forms a sliding fit with the sleeve 23 outside the guide shaft 22, allowing the float 31 to move freely up and down along the sleeve 23, ensuring that the float 31 slides along the sleeve 23 without jamming. Both ends of the through hole 311 of the float 31 are provided with abutment portions 312, which protrude from both ends of the float 31. When the float 31 rises to the top of the sealed container 31 or descends to the bottom, the end face of the float 31 will not directly collide with the end of the guide shaft 22. Only the abutment portions 312 abut against the end of the guide shaft 22, thus forming an anti-collision structure. The magnet 32 ​​is ring-shaped, with an outer ring having a north pole and an inner ring having a south pole, creating a thermal radiation ring. This ensures that the magnetic field polarity of the magnet 32 ​​is radially distributed, guaranteeing that the direction and magnitude of the externally detected magnetic field remain constant as the magnet 32 ​​rotates. The magnet 32 ​​is fixed to the upper part of the inner wall of the float 31 using high-temperature resistant sealant, and the magnet 32 ​​and the float 31 are coaxially aligned. The sealant has high-temperature resistance, making it suitable for the potentially high-temperature environments in semiconductor manufacturing, such as the heating of ultrapure water to generate steam, thus preventing the magnet 32 ​​from detaching at high temperatures. It should be noted that the overall average density of the float 31 and the magnet 32 ​​disposed inside the float 31 is less than the density of the liquid being measured, enabling the entire liquid level sensing component 3 to achieve buoyancy that rises and falls with the liquid level. The magnet 32 ​​can generate a stable radial magnetic field, which moves synchronously with the rise and fall of the float 31. This avoids the problem of magnetic field disorder caused by the axial polarity of the magnet 32 ​​when the float 31 rotates, ensuring that the direction and magnitude of the magnetic field are not affected by the rotation of the float 31. The stable magnetic field provides a trigger signal for the signal receiver 4, ensuring the continuity and accuracy of the liquid level measurement.

[0029] In some embodiments, the signal receiver 4 includes a plurality of arrayed reed switches 41. The reed switches 41 are located outside the sealed container 1 and are evenly arranged along the height direction of the sealed container 1. This ensures that when the internal annular magnet 32 ​​inside the sealed container 1 rises or falls to different heights, the reed switch 41 at the corresponding position can be accurately triggered, realizing the correspondence between the liquid level height and the position of the reed switch 41. When the internal annular magnet 32 ​​approaches, the reed in the reed switch 41 is magnetized, generating opposite polarity and attracting each other, thus making the circuit conductive. When the magnet moves away, the reed in the reed switch 41 springs open due to its own elasticity, thus breaking the circuit. The arrayed reed switches 41 can detect the specific height of the liquid level inside the sealed container by the on / off state of the reed switches 41 at different positions, replacing existing liquid level indication methods such as magnetic flips. This solves problems such as confusing indication, flashing, and half-red and half-white indication. Furthermore, since the reed switches 41 are located outside the sealed container 1, they do not come into contact with ultrapure water at all, avoiding the risk of contamination and meeting the high-cleanliness production requirements of semiconductors.

[0030] The assembly process of the magnetic liquid level measuring device 100 for ultrapure water of this utility model is as follows: A fixing plate 21 is welded to a designated position on the inner wall of the sealed container 1 to provide an installation reference for the guide shaft 22; a sleeve 23 is placed outside the guide shaft 22, ensuring that the sleeve 23 and the guide shaft 22 are tightly fitted without relative sliding, and that the length of the sleeve 23 covers the movement range of the float 31; then, the guide shaft 22 is vertically welded to the center of the fixing plate 21; a high-temperature resistant sealant is used to fix the annular magnet 32 ​​to the inner wall of the float 31, ensuring that the magnet 32 ​​and the float 31 are coaxial; the float 31 with the assembled annular magnet 32 ​​is fitted onto the sleeve 23 outside the guide shaft 22 through the central through hole 311; and reed switches 41 are fixedly installed at equal intervals along the height direction of the sealed container 1 outside the sealed container 1.

[0031] The working principle of the magnetic liquid level measuring device 100 for ultrapure water of this utility model is that ultrapure water is stored in the sealed container 1. When the liquid level of ultrapure water rises or falls, the float 31 in the liquid level sensing component 3 slides up and down synchronously along the sleeve 23 of the limiting guide component 2 under the action of buoyancy. The sleeve 23 cooperates with the central through hole 311 of the float 31, restricting the float 22 to move stably only along the axial direction of the guide shaft 22, avoiding lateral deviation that could contaminate the ultrapure water or interfere with the magnetic field, thus ensuring the accuracy and cleanliness of the movement. The annular magnet 32 ​​fixed on the inner wall of the float 31 rises and falls synchronously with the float 31, and the stable magnetic field generated by the annular magnet 32 ​​also moves along the height direction of the sealed container 1. Since the polarity of the magnetic field is distributed radially, even if the float 31 rotates, the direction and intensity of the magnetic field will not be disordered, providing a stable source for subsequent magnetic signal detection. The reed switches 41 arranged in an array outside the sealed container 1 are magnetized by the magnetic field and their ends are attracted when the annular magnet 32 ​​approaches, making the circuit conductive. When the magnet moves away, the reed in the reed switch 41 springs open due to its own elasticity, and the circuit is broken. The reed switches 41 at different heights correspond to different liquid levels. By detecting the position of the conductive reed switches 41, the liquid level height can be accurately determined.

[0032] The magnetic liquid level measuring device 100 for ultrapure water of this utility model includes a sealed container 1, a limiting guide assembly 2 disposed inside the sealed container 1, a liquid level sensing assembly 3 slidably sleeved on the limiting guide assembly 2, and a signal receiver 4 disposed outside the sealed container 1. The limiting guide assembly 2 includes a guide shaft 22 and a sleeve 23 sleeved outside the guide shaft 22. The signal receiver 4 includes multiple arrayed reed switches 41. This invention relates to a magnetic level measuring device 100 for ultrapure water. By using pure titanium for core components such as the sealed container 1 and float 31, which are in direct contact with ultrapure water, the device effectively isolates the reaction between the materials and the ultrapure water, preventing ion precipitation and material contamination, thus meeting the stringent purity requirements of semiconductor production. The device employs a guide shaft 22 and a sleeve 2 to prevent jamming of the level sensing component 3, ensuring long-term operational reliability. The level sensing component 3 uses a ring magnet 32 ​​with an outer N pole and an inner S pole, whose magnetic field polarity is radially distributed. This ensures that the direction and magnitude of the magnetic field in the external space remain constant regardless of whether the float 31 rotates, effectively solving the problem of magnetic field deviation caused by float rotation. The device eliminates the problem of magnetic field disturbance and provides a stable and reliable trigger signal for the external signal receiver, ensuring the accuracy and continuity of liquid level measurement. An array of reed switches 41 is used as the external signal receiver 4, replacing the traditional magnetic flip-flop. The reed switches 41 are located outside the sealed container 1, avoiding contact with ultrapure water and eliminating the risk of contamination. The liquid level is determined by detecting the on / off state of the reed switches 41 at different heights, fundamentally solving the problems of chaotic and flickering magnetic flip-flop indication. It can also easily convert the liquid level signal into an electrical signal for remote transmission. Furthermore, the device has a simple structural design, reliable connections between components, and can adapt to the high-temperature conditions of ultrapure water heating to generate steam, exhibiting strong environmental adaptability and a long service life.

[0033] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the scope of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A magnetic liquid level measuring device for ultrapure water, characterized in that, include: A sealed container, a limiting guide assembly disposed inside the sealed container, a liquid level sensing assembly slidably sleeved on the limiting guide assembly, and a signal receiver disposed outside the sealed container. The limiting guide assembly includes a guide shaft and a sleeve sleeved outside the guide shaft. The signal receiver includes multiple arrayed reed switches.

2. The magnetic liquid level measuring device for ultrapure water according to claim 1, characterized in that, The inner wall of the sealed container is made of pure titanium.

3. The magnetic level measuring device for ultrapure water according to claim 1, characterized in that, The limiting guide assembly also includes a fixing plate disposed on the sealed container. The fixing plate is made of pure titanium material and is fixed to the inner wall of the sealed container.

4. The magnetic liquid level measuring device for ultrapure water according to claim 3, characterized in that, One end of the guide shaft is vertically fixed at the center of the fixed plate, and the axial direction of the guide shaft is consistent with the height direction of the sealed container.

5. The magnetic level measuring device for ultrapure water according to claim 1, characterized in that, The sleeve is made of perfluoroalkoxyalkane, and the inner diameter of the sleeve matches the diameter of the guide shaft. The sleeve is fitted onto the outside of the guide shaft, and the sleeve fits tightly against the guide shaft.

6. The magnetic liquid level measuring device for ultrapure water according to claim 1, characterized in that, The liquid level sensing component includes a float sleeved on the outside of the sleeve and a magnet disposed inside the float.

7. The magnetic level measuring device for ultrapure water according to claim 6, characterized in that, The float is a hollow ring and is made of pure titanium.

8. The magnetic level measuring device for ultrapure water according to claim 7, characterized in that, The center of the float forms a cylindrical through hole, the diameter of which matches the outer surface of the sleeve, and a sliding fit is formed between the through hole and the sleeve outside the guide shaft.

9. The magnetic level measuring device for ultrapure water according to claim 7, characterized in that, The magnet is in the shape of a ring, and the magnet is a thermal radiation ring with an outer N pole and an inner S pole. The magnetic field polarity of the magnet is distributed radially.

10. The magnetic level measuring device for ultrapure water according to claim 1, characterized in that, The reed switches are disposed outside the sealed container, and a plurality of the reed switches are evenly arranged along the height direction of the sealed container.

Images