A vacuum gauge

Abstract

The utility model discloses a vacuum gauge, including the cylindrical first shell, its lower end inboard is equipped with three first clamping tongue, the annular magnet with second convex and having three first clamping groove is equipped in the shell, first cylinder spare is inserted magnet through -hole, and the outer wall is equipped with three first mounting hole and is assembled first clamping post, and the clamping post is rotatoryly connected with first clamping groove and is locked solid. First cylinder spare inner wall is equipped with first annular groove and is assembled first clamping spring to hold second cylinder spare, and the inner wall of top end is equipped with internal thread, and the vacuum gauge inner core is pressed down and is located below after the screw buckle is rotatively connected, and the sealing ring is arranged between the inner core and first cylinder spare and forms composite seal. The structure realizes quick assembly and disassembly, coaxial positioning and anti -vibration and prevents loose, improves the sealing reliability and the universality of inner core.

Description

Technical Field

[0001] This utility model relates to the field of measurement technology, specifically to a vacuum gauge. Background Technology

[0002] Vacuum gauges are used to measure and monitor gas pressure in vacuum systems. They are widely used in scanning electron microscopes, focusing ion beam microscopes, transmission electron microscopes, vacuum coating machines, pneumatic conveying systems, vacuum furnaces, vacuum dryers, freeze drying equipment, mass spectrometers, water ring vacuum pumps, surface analyzers, particle accelerators, space simulators, and other equipment requiring a vacuum environment for vacuum detection.

[0003] In existing products, the measuring core is often fixed inside the housing using threaded caps, retaining rings, or screw plates, and a single O-ring or end face gasket is commonly used for sealing. To prevent foreign objects from colliding with the core, some solutions incorporate protective sleeves or mesh covers. However, it is often difficult to balance the requirements for sleeve openings, coaxial positioning of the core and housing, assembly / disassembly efficiency, and anti-loosening structures. As field requirements for rapid maintenance, replaceable cores, and long-term stability increase, achieving a balance between "rapid assembly / reliable locking / high sealing / good air passage and protection" under limited space constraints has become a key issue that needs to be addressed for this type of product.

[0004] The shortcomings of existing technology: 1. Low assembly and maintenance efficiency: It generally relies on deep-stroke threaded caps or multiple screw plates, resulting in many assembly and disassembly steps and long time; the threads are prone to wear or jamming, which is not conducive to quick replacement of the inner core on site.

[0005] 2. Insufficient reliability of positioning and anti-loosening: Relying solely on friction clamping or a single retaining ring for limiting, axial movement or loosening is easily caused by equipment vibration and transportation impact, resulting in zero-point drift and poor repeatability.

[0006] 3. Poor versatility and compatibility: The interfaces of cores with different specifications or mechanisms (such as thermal conductivity type and ionization type) are not standardized, making it difficult to interchange the shell and core, resulting in high spare parts and maintenance costs.

[0007] 4. Large number of structural components and high manufacturing cost: The addition of screws, washers, pressure plates and complex machining steps affects assembly consistency and mass production yield.

[0008] Therefore, existing technologies have shortcomings and need further improvement. Utility Model Content

[0009] In view of the problems existing in the prior art, this utility model provides a vacuum gauge.

[0010] To achieve the above objectives, the specific solution of this utility model is as follows: This utility model provides a vacuum gauge, comprising: The first outer shell is cylindrical, and its lower inner side is provided with three equidistant first latches; A ring magnet is disposed inside the first housing. The outer periphery of the ring magnet is provided with a second outward protrusion for limiting and cooperating with the first housing, and three first slots are formed on its inner side. The first cylindrical component is inserted into the central through hole of the annular magnet and is coaxial with it. The outer wall of the first cylindrical component is provided with three first mounting holes. The first locking pins are respectively inserted into the three first mounting holes, and the three first locking pins and the three first locking slots are engaged by rotation to lock the first cylindrical piece to the annular magnet. The first annular groove is disposed on the inner wall of the first cylindrical component; The first retaining ring is assembled in the first annular groove; The second cylindrical component is installed inside the first cylindrical component, and its lower end is supported by the first retaining spring. The vacuum gauge core is located above the second cylindrical component and disposed inside the first cylindrical component; An internal thread is provided on the inner wall of the top end of the first cylindrical component; A threaded snap fastener is screwed onto the internal thread and located above the inner core of the vacuum gauge; A sealing ring is disposed between the inner core of the vacuum gauge and the first cylindrical component; The first latch engages with the second outward protrusion of the annular magnet to axially limit the annular magnet from the first outer shell.

[0011] Furthermore, the three first locking posts and the three first locking slots are distributed at equal angles. The first locking slot is an "L"-shaped or a rotary locking slot with a stop structure, which is used to achieve rotational locking after insertion.

[0012] Furthermore, the first latch and the second protrusion form a rotatable locking engagement. The first outer shell rotates relative to the annular magnet by a predetermined angle in the circumferential direction to complete the locking, and rotates in the opposite direction to release the locking for assembly and disassembly.

[0013] Furthermore, the second cylindrical component is a protective sleeve structure, with multiple through holes arranged in a circumferential array on its cylinder wall to ensure the flow between the measured gas and the inner core of the vacuum gauge, while providing mechanical protection for the inner core of the vacuum gauge.

[0014] Furthermore, the lower end face of the threaded buckle forms an annular shoulder, which is used to press the vacuum gauge inner core downward and simultaneously compress the sealing ring to form an axial seal.

[0015] Furthermore, the sealing ring is an O-ring, which is disposed between the upper step of the first cylindrical component and the outer periphery of the inner core of the vacuum gauge to achieve a composite seal in the radial and axial directions.

[0016] Furthermore, the outer circumferential surface of the annular magnet is provided with several radial reinforcing ribs or heat dissipation ribs to improve the holding force and structural strength and facilitate assembly and disassembly operations.

[0017] Furthermore, the side wall of the first housing is provided with an indicator window, which is used to install indicator lights or status indicators to display the working status.

[0018] Furthermore, a mounting flange is integrally formed at the lower end of the first cylindrical component, and the mounting flange is used to connect with the interface flange of the system under test.

[0019] Furthermore, the first outer shell, the annular magnet, the first cylindrical component, the second cylindrical component, and the inner core of the vacuum gauge are all coaxially arranged along the same central axis, and the opening of the first retaining ring is arranged facing upward to prevent the second cylindrical component from shifting downward and dislodging when subjected to vibration.

[0020] The technical solution of this utility model has the following beneficial effects: 1. Quick assembly and disassembly, efficient maintenance The rotational engagement of the "first locking post - first locking groove" and the locking action of the "first locking tongue - second outward protrusion" allow for easy locking by pushing in and rotating. Combined with the single-piece clamping structure of the threaded buckle, the process of replacing the inner core is significantly simplified, and downtime is reduced.

[0021] 2. Redundant system for vibration resistance and loosening prevention The system features three parallel paths: circumferential rotation locking (clamp / slot), axial locking (clamp tongue / outer protrusion), and threaded pre-tightening. These paths are independent of each other and can maintain positioning and sealing even if a single path is loosened by impact, ensuring high long-term stability.

[0022] 3. Good coaxial positioning accuracy and repeatability The first outer shell, the ring magnet, the first / second cylindrical parts, and the inner core are arranged coaxially, with clear assembly guidance and good position repeatability after disassembly and assembly, which can reduce zero drift and the frequency of repeated calibration.

[0023] 4. Fewer structural components, better consistency between manufacturing and mass production By eliminating small parts such as multi-screw pressure plates and using standard parts (circlips, O-rings, threaded clips) and rotary snap-fit ​​connections, the assembly process is simplified, which is beneficial for batch consistency and cost control. Attached Figure Description

[0024] Figure 1 This is a perspective view of the present invention; Figure 2 This is a cross-sectional view of the present invention; Figure 3 This is an exploded view of the present invention from a top-down perspective; Figure 4 This is an exploded view of the present invention from a low angle; Attached image captions: 1. First outer shell; 2. First latch; 3. Ring magnet; 4. First slot; 5. First cylindrical component; 6. First mounting hole; 7. First locking post; 8. First annular groove; 9. First retaining ring; 10. Second cylindrical component; 11. Vacuum gauge inner core; 12. Threaded buckle; 13. Sealing ring. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0026] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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 based on the specific circumstances.

[0027] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0028] In the description of this embodiment, the terms "upper," "lower," "front," "rear," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0029] Combination Figures 1-4 As shown, this utility model provides a vacuum gauge, comprising: The first outer shell 1 is cylindrical, and its lower inner side is provided with three equidistant first latches 2; An annular magnet 3 is disposed inside the first outer shell 1. The annular magnet 3 has a second outward protrusion on its outer periphery for limiting and cooperating with the first outer shell 1, and three first slots 4 are formed on its inner side. The first cylindrical component 5 is inserted into the central through hole of the annular magnet 3 and is coaxial with it. The outer wall of the first cylindrical component 5 is provided with three first mounting holes 6. The first locking pin 7 is respectively inserted into the three first mounting holes 6. The three first locking pins 7 and the three first locking slots 4 are engaged by rotation to lock the first cylindrical part 5 to the annular magnet 3. The first annular groove 8 is disposed on the inner wall of the first cylindrical component 5; The first snap ring 9 is assembled in the first annular groove 8; The second cylindrical component 10 is installed inside the first cylindrical component 5, and its lower end is supported by the first retaining spring 9; The vacuum gauge inner core 11 is located above the second cylindrical component 10 and disposed inside the first cylindrical component 5; An internal thread is provided on the inner wall of the top end of the first cylindrical component 5; A threaded snap fastener 12 is screwed onto the internal thread and located above the vacuum gauge inner core 11; A sealing ring 13 is disposed between the inner core 11 of the vacuum gauge and the first cylindrical component 5; The first latch 2 engages with the second outward protrusion of the annular magnet 3 to axially limit the annular magnet 3 and the first outer shell 1.

[0030] The three first locking posts 7 and the three first locking slots 4 are distributed at equal angles. The first locking slot 4 is an "L" shaped or a rotating locking slot with a stop structure, which is used to achieve rotation locking after insertion.

[0031] The first latch 2 and the second protrusion form a rotating latching engagement. The first outer shell 1 is locked after rotating circumferentially relative to the annular magnet 3 by a predetermined angle, and is unlocked by rotating in the opposite direction for assembly and disassembly.

[0032] The second cylindrical component 10 is a protective sleeve structure, and its cylinder wall is provided with multiple through holes arranged in a circumferential array to ensure the flow between the gas being measured and the vacuum gauge inner core 11, while providing mechanical protection for the vacuum gauge inner core 11.

[0033] The lower end face of the threaded buckle 12 forms an annular shoulder, which is used to press the vacuum gauge inner core 11 downward and simultaneously compress the sealing ring 13 to form an axial seal.

[0034] The sealing ring 13 is an O-ring, which is disposed between the upper step of the first cylindrical part 5 and the outer periphery of the inner core 11 of the vacuum gauge to achieve a composite seal in the radial and axial directions.

[0035] The outer circumferential surface of the annular magnet 3 is provided with several radial reinforcing ribs or heat dissipation ribs to improve the holding force and structural strength and facilitate assembly and disassembly.

[0036] The side wall of the first housing 1 is provided with an indicator window, which is used to install indicator lights or status indicators to display the working status.

[0037] The lower end of the first cylindrical component 5 is integrally formed with a mounting flange, which is used to connect with the interface flange of the system under test.

[0038] The first outer shell 1, the annular magnet 3, the first cylindrical component 5, the second cylindrical component 10 and the vacuum gauge inner core 11 are all coaxially arranged along the same central axis. The opening of the first retaining ring 9 is arranged facing upward to prevent the second cylindrical component 10 from shifting downward and dislodging when subjected to vibration.

[0039] The principle of this utility model is as follows: 1. Assembly and positioning principles: The first cylindrical component 5 is inserted into the through hole of the annular magnet 3 from bottom to top, and the first locking pins 7 are inserted through the three first mounting holes 6. After insertion, it is rotated circumferentially so that the three first locking pins 7 respectively enter the three first locking grooves 4 on the inner side of the annular magnet 3 and lock in place, forming a rotational locking connection. This locking connection provides anti-loosening in the circumferential direction and forms a bidirectional limiting between the three first locking tongues 2 of the first outer shell 1 and the second outward protrusion of the annular magnet 3 in the axial direction, thereby realizing the coaxial positioning and vibration-resistant fixation of the annular magnet 3, the first cylindrical component 5 and the first outer shell 1.

[0040] 2. The principle of support and guidance: A first retaining ring 9 is installed in the first annular groove 8 on the inner wall of the first cylindrical component 5; the second cylindrical component 10 is fitted from the top and supported by the first retaining ring 9 at its lower end to form a suspension support, which not only limits the axial position of the second cylindrical component 10, but also provides assembly guidance. The second cylindrical component 10 serves as a protective sleeve, and the circumferential openings (or through-hole arrays) on its cylindrical wall ensure that the gas to be measured can freely enter the inner cavity, while also providing mechanical protection and airflow rectification for the vacuum gauge inner core 11, reducing measurement drift caused by DC scouring.

[0041] 3. Compressing and sealing principle: The internal thread at the top of the first cylindrical component 5 mates with the threaded snap fastener 12. During assembly, the vacuum gauge inner core 11 is placed inside the first cylindrical component 5, with a sealing ring 13 placed between its outer circumference and the first cylindrical component 5. Then, the threaded snap fastener 12 is tightened, and the annular shoulder at the lower end of the snap fastener presses downwards against the vacuum gauge inner core 11 and squeezes the sealing ring 13, causing the sealing ring 13 to be simultaneously compressed axially and radially, forming a composite seal of end face + radial direction. The tightening torque is transmitted through “threaded snap fastener 12 → inner core 11 upper cover / shoulder → sealing ring 13 → first cylindrical component 5 step”, obtaining a stable preload force and suppressing the fretting and leakage of the inner core 11 under equipment vibration.

[0042] 4. Formation of the gas channel and measurement area: After the vacuum gauge is installed at the interface of the system under test, the gas to be measured enters the inner cavity of the first cylindrical component 5 through the through hole of the second cylindrical component 10, forming a measurement space around the inner core 11. The composite seal isolates this space from the outside atmosphere, ensuring that the inner core 11 is directly connected to the system under test without bypass leakage. The coaxial positioning of the second cylindrical component 10 and the first cylindrical component 5 makes the measurement area small and symmetrical, thereby shortening the gas exchange path, reducing hysteresis, improving response speed and zero-point consistency after repeated assembly.

[0043] 5. Measurement Mechanism (Core Compatibility Principle): This structure does not limit the core mechanism and can be adapted to standard cores such as thermally conductive or ionized cores: Thermal conductivity type (Pirani / thermocouple) core: The heating wire (such as tungsten wire or platinum wire) in the core operates under constant current or constant temperature control. The thermal conductivity of the measured gas to the heating wire changes with pressure, causing a change in the temperature (or resistance) of the heating wire; by measuring the change in resistance or the compensation power required to maintain constant temperature, a pressure-related output signal is obtained. Its heat exchange approximately satisfies: Qgas∝(Tw Tg) f(P); Where f(P) is the heat transfer coefficient function related to pressure P.

[0044] Ionization type (hot cathode / cold cathode) core: Electrons generated by the filament or electric field collide with gas molecules and ionize, and ions are collected under the action of the electric field to form an ion current I_i; Under specified electrode structure and voltage conditions, I_i≈K P; This is used to calculate the pressure.

[0045] With the above compatibility design, users only need to replace the inner core to cover the range requirements from rough vacuum to high vacuum.

[0046] 6. Vibration resistance and anti-loosening principle: The three first locking pins and three first locking slots form a three-point circumferential locking; the three first locking tongues of the first outer shell and the second outward protrusion of the annular magnet form an axial locking; the threaded buckle provides continuous pre-tightening. These three independent limiting-locking-pre-tightening paths are not coupled to each other, forming a redundant anti-vibration system: even if a single connection is loosened by impact, the other two mechanisms can still maintain sealing and positioning, ensuring long-term stability.

[0047] 7. Maintenance and Replacement Principles: During on-site maintenance, simply unscrew the threaded clip counterclockwise and remove the vacuum gauge core for replacement; the second cylindrical component remains in place under the support of the first retaining spring, preventing internal parts from scattering; when reinstalling, the core automatically centers itself guided by the second cylindrical component, and tightening the threaded clip restores the original pre-tightening and sealing. Since all limiting and guiding surfaces are coaxial circular surfaces, the reproducibility of assembly positions after disassembly and reassembly is high, reducing the workload of repetitive calibration.

[0048] 8. The auxiliary role of toroidal magnets: In addition to serving as an outer peripheral grip and locking component, the ring magnet can provide temporary magnetic positioning or boundary adsorption of fine ferromagnetic powder on devices with matching metal positioning plates, further suppressing foreign objects from entering the measurement area; this function is an optional implementation and does not affect the above-mentioned assembly and sealing mechanism.

[0049] In summary, this utility model, through the synergistic design of "rotational snap-fit ​​+ suspension support + composite sealing + coaxial guidance", achieves rapid assembly and disassembly, reliable anti-loosening, high sealing and universal inner core performance under the condition of limited volume, ensuring that the vacuum gauge obtains stable and repeatable pressure measurement output under different working conditions.

[0050] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the inventive concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the protection scope of the present utility model.

Claims

1. A vacuum gauge, characterized in that, include: The first outer shell is cylindrical, and its lower inner side is provided with three equidistant first latches; A ring magnet is disposed inside the first housing. The outer periphery of the ring magnet is provided with a second outward protrusion for limiting and cooperating with the first housing, and three first slots are formed on its inner side. The first cylindrical component is inserted into the central through hole of the annular magnet and is coaxial with it. The outer wall of the first cylindrical component is provided with three first mounting holes. The first locking pins are respectively inserted into the three first mounting holes, and the three first locking pins and the three first locking slots are engaged by rotation to lock the first cylindrical piece to the annular magnet. The first annular groove is disposed on the inner wall of the first cylindrical component; The first retaining ring is assembled in the first annular groove; The second cylindrical component is installed inside the first cylindrical component, and its lower end is supported by the first retaining spring. The vacuum gauge core is located above the second cylindrical component and disposed inside the first cylindrical component; An internal thread is provided on the inner wall of the top end of the first cylindrical component; A threaded snap fastener is screwed onto the internal thread and located above the inner core of the vacuum gauge; A sealing ring is disposed between the inner core of the vacuum gauge and the first cylindrical component; The first latch engages with the second outward protrusion of the annular magnet to axially limit the annular magnet from the first outer shell.

2. The vacuum gauge according to claim 1, characterized in that, The three first locking posts and three first locking slots are distributed at equal angles. The first locking slot is an "L" shaped or a rotary locking slot with a stop structure, which is used to achieve rotation locking after insertion.

3. The vacuum gauge according to claim 1, characterized in that, The first latch and the second protrusion form a rotatable locking engagement. The first outer shell rotates relative to the annular magnet by a predetermined angle in the circumferential direction to complete the locking, and rotates in the opposite direction to release the locking for assembly and disassembly.

4. The vacuum gauge according to claim 1, characterized in that, The second cylindrical component is a protective sleeve structure, and its cylinder wall is provided with multiple through holes arranged in a circumferential array to ensure the flow between the gas being measured and the inner core of the vacuum gauge, while providing mechanical protection for the inner core of the vacuum gauge.

5. The vacuum gauge according to claim 1, characterized in that, The lower end face of the threaded buckle forms an annular shoulder, which is used to press the vacuum gauge inner core downward and simultaneously compress the sealing ring to form an axial seal.

6. The vacuum gauge according to claim 1, characterized in that, The sealing ring is an O-ring, which is disposed between the upper step of the first cylindrical component and the outer periphery of the inner core of the vacuum gauge to achieve a composite seal in the radial and axial directions.

7. The vacuum gauge according to claim 1, characterized in that, The outer circumferential surface of the ring magnet is provided with several radial reinforcing ribs or heat dissipation ribs to improve the holding force and structural strength and facilitate assembly and disassembly.

8. The vacuum gauge according to claim 1, characterized in that, The side wall of the first housing is provided with an indicator window, which is used to install indicator lights or status indicators to display the working status.

9. The vacuum gauge according to claim 1, characterized in that, The lower end of the first cylindrical component is integrally formed with a mounting flange, which is used to connect with the interface flange of the system under test.

10. The vacuum gauge according to claim 1, characterized in that, The first outer shell, the annular magnet, the first cylindrical component, the second cylindrical component, and the inner core of the vacuum gauge are all coaxially arranged along the same central axis. The opening of the first retaining ring is arranged facing upward to prevent the second cylindrical component from shifting downward and dislodging when subjected to vibration.

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