A moisture-resistant module for liquid level sensor

Abstract

The present invention discloses a moisture-proof module for a liquid level sensor, which belongs to the field of sensor technology. The moisture-proof module for the liquid level sensor comprises a cable and an air duct inserted into the cable, and the moisture-proof module comprises a connecting plug, an air bag and a shell assembly. The connecting plug is sleeved on the cable, and the air duct is inserted into the connecting plug; the air bag is coated on the connecting plug and communicated with the air duct; the shell assembly presses the air bag on the connecting plug to seal the air bag with the connecting plug. The moisture-proof module for the liquid level sensor of the present invention, through the cooperation of the connecting plug, the air bag and the shell assembly, can not only balance the internal air pressure of the liquid level sensor with the outside world, but also prevent external water vapor from entering the interior through the air duct, thereby achieving both measurement accuracy and solving the adverse effects caused by condensation, avoiding the on-site maintenance costs caused thereby, improving the reliability of the liquid level sensor, avoiding waste and repeated investment, and reducing costs.

Description

Technical Field

[0001] The present invention relates to the technical field of sensors, and in particular to a moisture-resistant module for a liquid level sensor. Background Art

[0002] In order to ensure measurement accuracy, submersible liquid level sensors currently on the market generally use gauge pressure sensors, which have an air duct on the back to ensure connectivity with the atmosphere. However, as the sensor and cable are heated or cooled, the volume inside the cable air duct increases or decreases as the pressure increases or decreases. Condensed water will enter the sensor through the air duct, damaging the components inside the sensor, requiring periodic on-site maintenance, or even causing damage to the sensor. The existing technology is to install a polymer plug at the end of the air duct to ensure that the gas in the air duct can be quickly discharged through the polymer plug, balancing the internal and external air pressures and extending the service life. However, the polymer plug can prevent large water droplets (particle size 0.02μm or larger) from entering the air duct, but in a humid environment, it cannot prevent water vapor (particle size 0.004μm or less) from entering the air duct from the outside, causing damage to the sensor and other components. Summary of the Invention

[0003] The object of the present invention is to provide a moisture-proof module for a liquid level sensor, which can not only balance the internal air pressure of the sensor with that of the outside world but also prevent external water vapor from entering the module, thereby achieving a protective effect that can not only ensure measurement accuracy but also completely and permanently solve the problem of condensation, avoid the on-site maintenance costs caused by it, improve reliability, and avoid waste and repeated investment.

[0004] To achieve this object, the present invention adopts the following technical solutions:

[0005] A moisture-proof module for a liquid level sensor, the liquid level sensor comprising a cable and an air guide tube passing through the cable, the moisture-proof module comprising:

[0006] A connecting plug is sleeved on the cable, and the air guide tube is passed through the connecting plug;

[0007] an air bag, covering the connecting plug and communicating with the airway tube;

[0008] The housing assembly presses the airbag onto the connecting plug to seal the airbag and the connecting plug.

[0009] Optionally, the moisture-proof module further includes a sealing member, which is arranged between the airbag and the housing assembly.

[0010] Optionally, a through hole is provided in the connecting plug, and the cable and the air duct are passed through the through hole. The longitudinal section of the connecting plug is T-shaped, and includes a first connecting part and a second connecting part connected to the first connecting part. The outer diameter of the second connecting part is larger than the outer diameter of the first connecting part, and the second connecting part is enclosed in the airbag.

[0011] Optionally, the shell assembly includes a shell, one end of the shell is connected to the connecting plug, and an annular step is circumferentially provided inside the end of the shell connected to the connecting plug. The shell is sleeved on the connecting plug, and the inner circumferential surface of the annular step presses the airbag on the first connecting part, and / or the end face of the annular step presses the airbag on the second connecting part.

[0012] Optionally, a signal line is passed through the cable, a first mounting hole is opened on the shell, the signal line is passed through the first mounting hole, and the signal line and the airbag are separated by the first mounting hole.

[0013] Optionally, the shell assembly also includes a cover body connected to the shell, the shell and the cover body form a accommodating space, the airbag is arranged in the accommodating space, a second mounting hole corresponding to the first mounting hole is opened on the cover body, and a gap is provided axially between the cover body and the shell, and the accommodating space is connected to the external atmosphere through the gap and the second mounting hole.

[0014] Optionally, the first connecting portion is provided with an opening along the axial direction, and the signal line extends from the opening.

[0015] Optionally, the moisture-proof module further includes a fixed joint, which is sleeved on the cable and presses the connecting plug against the cable to seal the cable and the connecting plug.

[0016] Optionally, a desiccant is provided in the airbag.

[0017] Optionally, the airbag is a polymer waterproof airbag, and the connecting plug is a polymer waterproof plug.

[0018] Beneficial effects of the present invention:

[0019] The present invention provides a moisture-proof module for a liquid level sensor, wherein a connecting plug is sleeved on a cable and an air duct, and an airbag has the elasticity to cover the connecting plug, so that the airbag and the connecting plug are sleeved on one end of the air duct, connecting the air duct and the airbag; when the temperature in the air duct rises, the volume of the airbag increases until it is balanced with the atmospheric pressure, thereby ensuring the balance of air pressure inside and outside the air duct; similarly, when the temperature drops, the volume of the airbag decreases until it is balanced with the atmospheric pressure, thereby ensuring the balance of air pressure inside and outside the air duct.

[0020] The airbag is sealed against the connecting plug, preventing external moisture from entering the air duct through the gap between the two, thereby protecting the liquid level sensor and related components and extending the service life of the equipment. Due to the elasticity of the airbag, it is difficult to ensure a reliable and sealed connection when connecting the airbag and the connecting plug. By pressing the airbag against the connecting plug through the housing assembly, the structure is simple and compact, the connection is reliable, and it is easy to assemble and disassemble. The moisture-blocking module balances the internal air pressure of the liquid level sensor with that of the outside world and prevents external moisture from entering through the air duct, thereby ensuring measurement accuracy while resolving the adverse effects of condensation and avoiding the resulting on-site maintenance costs. This improves the reliability of the liquid level sensor, avoids waste and duplication of investment, and reduces costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 1 is a schematic structural diagram of a moisture-blocking module for a liquid level sensor provided in a specific embodiment of the present invention;

[0022] Figure 2 is an exploded view of a moisture-blocking module for a liquid level sensor provided in a specific embodiment of the present invention;

[0023] Figure 3 1 is a front view of a moisture-blocking module for a liquid level sensor provided in a specific embodiment of the present invention;

[0024] Figure 4 yes Figure 3 AA cross-sectional view;

[0025] Figure 5 It is a structural schematic diagram of a shell provided by a specific embodiment of the present invention.

[0026] In the picture:

[0027] 100-cable; 200-air guide tube; 300-signal line;

[0028] 1-connecting plug; 11-first connecting portion; 111-opening; 112-sealing groove; 12-second connecting portion; 121-avoidance groove; 13-through hole;

[0029] 2-airbag;

[0030] 3-housing assembly; 31-cover; 311-second mounting hole; 32-housing; 321-annular step; 322-first mounting hole; 33-gap;

[0031] 4-Fixed joint;

[0032] 5- Seals. DETAILED DESCRIPTION

[0033] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved more clearly, the technical solutions of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0034] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0035] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0036] The liquid level sensor includes a sensor body, a cable 100 connected to the body, and an air duct 200 passing through the cable 100. The air duct 200 is used to discharge internal gas to balance the internal and external air pressures and extend the service life. To prevent water vapor from entering the air duct 200 in a humid environment and affecting the use of the liquid level sensor, this embodiment provides a moisture-proof module for the liquid level sensor. The moisture-proof module is provided at the end of the air duct 200 opposite to the sensor body. Figures 1-4 As shown, the moisture-proof module includes a connecting plug 1, an airbag 2 and a shell assembly 3; specifically, the connecting plug 1 is sleeved on the cable 100, and the air duct 200 is passed through the connecting plug 1; the airbag 2 is covered on the connecting plug 1 and is connected to the air duct 200; the shell assembly 3 presses the airbag 2 on the connecting plug 1 to ensure a sealed connection between the airbag 2 and the connecting plug 1.

[0037] Connecting plug 1 is fitted over cable 100 and air tube 200. Airbag 2, with its elasticity, wraps around connecting plug 1, enveloping one end of air tube 200 and connecting airbag 2. According to the formula PV = nRT, when the temperature inside air tube 200 rises, airbag 2 increases in volume until it reaches atmospheric pressure, thereby ensuring pressure balance inside and outside air tube 200. Similarly, when the temperature drops, airbag 2 decreases in volume until it reaches atmospheric pressure, thereby ensuring pressure balance inside and outside air tube 200. The airbag 2 is sealed to connecting plug 1, preventing external moisture from passing through the gap between the airbag 2 and connecting plug 1 and into the interior of air tube 200. This protects the liquid level sensor and related components, extending the service life of the equipment. Due to the elasticity of the airbag 2, ensuring a reliable and sealed connection between the airbag 2 and the connecting plug 1 is difficult. By pressing the airbag 2 against the connecting plug 1 with the housing assembly 3, the structure is simple and compact, the connection is reliable, and it is easy to assemble and disassemble. The moisture barrier module not only balances the internal air pressure of the liquid level sensor with that of the outside world, but also prevents external moisture from entering the interior through the air guide tube 200. This ensures measurement accuracy while also addressing the adverse effects of condensation, avoiding the associated on-site maintenance costs. This improves the reliability of the liquid level sensor, avoids waste and duplication of investment, and reduces costs.

[0038] Optionally, the moisture barrier module further includes a seal 5 disposed between the airbag 2 and the housing assembly 3. The housing assembly 3 compresses the airbag 2 against the connecting plug 1 via the seal 5, further improving the seal between the airbag 2 and the connecting plug 1. In this embodiment, the seal is a sealing ring. The connecting plug 1 is provided with at least one sealing groove 112. The housing assembly 3 compresses the airbag against the sealing groove 112 via the sealing ring to achieve a seal. The seal 5 also prevents direct contact between the airbag 2 and the housing assembly 3, preventing damage to the airbag 2 and increasing the service life of the airbag 2. During installation, the sealing ring is sleeved on the airbag 2 and part of the connecting plug 1, and the outer shell component 3 presses the sealing ring and is connected to the connecting plug 1. To verify the airtightness between the airbag 2 and the connecting plug 1, it can be judged by the contact between the outer shell component 3 and the sealing ring. When there is no seal between the outer shell component 3 and the airbag 2, it means that the sealing ring has not pressed the airbag 2 and the connecting plug 1, that is, there is no sealed connection between the airbag 2 and the connecting plug 1; on the contrary, when the outer shell component 3, the sealing ring and the airbag 2 are sealed, it means that the airbag 2 and the connecting plug 1 are sealed.

[0039] Because polymer materials can block water droplets larger than 0.02 μm, airbag 2 can optionally be a waterproof polymer airbag to further prevent external moisture from entering the airway tube 200 through the airbag 2. Specifically, airbag 2 can be a highly elastic polymer rubber airbag. Similarly, connecting plug 1 can be a waterproof polymer plug, specifically a polymer rubber plug. Optionally, a desiccant can be incorporated into airbag 2 to absorb existing moisture within the airway tube 200, further protecting the liquid level sensor and related components.

[0040] Optionally, continue with reference to Figures 1-4 The fixed joint 4 is sleeved on the cable 100, and presses the connecting plug 1 on the cable 100, so that the connecting plug 1 and the cable 100 are fixed as one, so that the moisture-proof module is fixed on the cable 100 and then connected to the liquid level sensor, which is convenient and reliable to use; at the same time, the connecting plug 1 presses on the cable 100, so that the cable 100 and the connecting plug 1 are sealed and connected, which can prevent external water vapor from entering through the gap between the connecting plug 1 and the cable 100, thereby improving the sealing performance. The fixed joint 4 can adopt standard parts in the existing technology, and the specific structure will not be repeated. When in use, the fixed joint 4 is first sleeved on the cable 100 and the connecting plug 1 as a whole, and then the nut on the fixed joint 4 is tightened to press the connecting plug 1 on the cable 100.

[0041] like Figure 2 As shown, optionally, a through hole 13 is opened in the connecting plug 1, and the cable 100 and the air guide tube 200 are passed through the through hole 13. The longitudinal section of the connecting plug 1 is T-shaped, which includes a first connecting part 11 and a second connecting part 12 connected to the first connecting part 11. The outer diameter of the second connecting part 12 is larger than the outer diameter of the first connecting part 11. The second connecting part 12 is covered in the airbag 2. The second connecting part 12 can support the elastic airbag 2, thereby improving the connection reliability and sealing between the connecting plug 1 and the airbag 2.

[0042] Optionally, the housing assembly 3 includes a shell 32, one end of which is connected to the connecting plug 1. Specifically, an internal thread may be provided on the shell 32, and an external thread may be provided on the first connecting portion 11 of the connecting plug 1, and the shell 32 and the first connecting portion 11 are connected by threaded fitting; or connecting holes are provided on both the shell 32 and the first connecting portion 11 of the connecting plug 1, and fasteners pass through the two connecting holes to achieve a detachable connection between the shell 32 and the connecting plug 1; or the shell 32 and the connecting plug 1 are connected by bonding or welding, etc., without limitation.

[0043] In this embodiment, Figure 5As shown, an annular step 321 is circumferentially provided inside one end of the shell 32 connected to the connecting plug 1, and the shell 32 is sleeved on the connecting plug 1. The inner circumferential surface of the annular step 321 presses the airbag 2 on the first connecting part 11, so that the airbag 2 is sealed and connected to the first connecting part 11. The end face of the annular step 321 presses the airbag 2 on the second connecting part 12, so that the airbag 2 is sealed and connected to the second connecting part 12, thereby improving the reliability of the sealed connection between the airbag 2 and the connecting plug 1. In this embodiment, the shell 32 and the connecting plug 1 are connected by an interference fit, which can not only realize the connection between the shell 32 and the connecting plug 1, but also improve the sealing between the shell 32, the connecting plug 1 and the airbag 2.

[0044] Optionally, refer to Figure 5 The cable 100 also has a signal line 300 passing through it. The shell 32 has a first mounting hole 322 formed therein. The signal line 300 passes through the first mounting hole 322. The first mounting hole 322 separates the signal line 300 from the airbag 2 to prevent interference between the structures. Optionally, a raised portion is provided on the inner wall of the shell 32, and the first mounting hole 322 is provided on the raised portion. When the shell 32 is sleeved and installed on the connecting plug 1, a clearance groove 121 for avoiding the raised portion is provided on the second connecting portion 12 to prevent interference between the connecting plug 1 and the shell 32. In this embodiment, the shell 32 and the connecting plug 1 are connected by an interference fit, which prevents the shell 32 and the connecting plug 1 from rotating relative to each other and affecting the fit between the clearance groove 121 and the raised portion, making installation convenient. The airbag 2 is elastic and can be elastically deformed according to the shape of the raised portion to avoid interference.

[0045] Optionally, the housing assembly 3 further includes a cover 31 connected to the shell 32. The shell 32 and the cover 31 form a receiving space, and the airbag 2 is arranged in the receiving space to protect the airbag 2. The cover 31 is provided with a second mounting hole 311 corresponding to the first mounting hole 322, so that the signal line is passed through the first mounting hole 322 and the second mounting hole 311. Specifically, Figure 4 As shown, a gap 33 is provided axially between the cover body 31 and the shell, and the accommodating space is connected to the external atmosphere through the gap 33 and the second mounting hole 311, so that the airbag 2 is in contact with the external atmosphere, which facilitates the adjustment of the pressure balance between the airbag 2 and the atmosphere.

[0046] Optionally, the housing 32 and the cover 31 are connected by a detachable connection such as a threaded connection or other means. Optionally, the housing 32 and the cover 31 are connected by an interference fit, facilitating communication and installation between the first mounting hole 322 and the second mounting hole 311. In this embodiment, the inner ring of the cover 31 is interference-fitted with the outer ring of the housing 32. The height of the inner ring of the cover 31 is greater than the height of the outer ring of the housing 32, thereby creating an axial gap 33 when the housing 32 and the cover 31 are connected. In other embodiments, the outer ring of the cover 31 can also be interference-fitted with the inner ring of the housing 32. The housing 32 and the connecting plug 1 can be connected by a detachable connection or other connection means, or the housing assembly 3 and the connecting plug 1 can be made into an integral structure, without limitation.

[0047] Optionally, the first connecting portion 11 is provided with an opening 111 in the axial direction, and the signal line 300 extends from the opening 111 . The opening 111 facilitates the connection plug 1 to be sleeved on the cable 100 , thereby facilitating installation.

[0048] In this embodiment, the connecting plug 1 , the housing 32 and the cover plate are all rotating bodies and are installed along the cable 100 to prevent the cable 100 from bending.

[0049] Since plastic materials have the advantages of corrosion resistance, aging resistance, and high and low temperature resistance, in this embodiment, the shell 32 and the cover 31 are respectively a plastic shell 32 and a plastic cover 31, which have high reliability, can extend the service life, and have good reliability when containing the airbag 2.

[0050] Further optionally, the installation process steps of the moisture-proof module include:

[0051] S1: The desiccant is placed in the airbag 2, and the airbag 2 is wrapped around the connecting plug 1;

[0052] S2: The sealing ring is sleeved on the first connecting portion 11 and arranged in the sealing groove 112;

[0053] S3: The airbag 2 and the connecting plug 1 are installed on the housing 32, and the housing 32 presses the airbag 2 on the connecting plug 1 through the sealing ring to achieve a sealed connection between the airbag 2 and the connecting plug 1;

[0054] S4: The cable 100 is passed through the connecting plug 1, and the air guide tube 200 is inserted into the connecting plug 1 to communicate with the airbag 2;

[0055] S5: The fixed connector 4 is sleeved on the cable 100;

[0056] S6: The signal line 300 extends from the opening 111 of the connecting plug 1 and passes through the first mounting hole 322 and the second mounting hole 311 of the housing 32 and the cover 31 in sequence;

[0057] S7: The fixed connector 4 is locked on the connecting plug 1, so that the cable 100 and the connecting plug 1 are locked together to form a solid whole;

[0058] S8: The cover 31 is connected to the housing 32. Before the cover 31 is connected to the housing 32, the installation of the airbag 2 and other structures may be adjusted.

[0059] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A moisture-proof module for a liquid level sensor, the liquid level sensor comprising a cable (100) and an air guide tube (200) passing through the cable (100), characterized in that: The moisture barrier module includes: A connecting plug (1) is sleeved on the cable (100), the air guide tube (200) is passed through the connecting plug (1), and the connecting plug (1) is a polymer waterproof plug; An airbag (2), the airbag (2) having elasticity and capable of covering the connecting plug (1) and being in communication with the air guide tube (200), the airbag (2) being a polymer waterproof airbag, and a desiccant being provided inside the airbag (2); A housing assembly (3) presses the airbag (2) onto the connecting plug (1) to seal the airbag (2) to the connecting plug (1); The moisture-proof module further comprises a sealing member (5), the sealing member (5) being arranged between the airbag (2) and the shell assembly (3), the sealing member (5) being a sealing ring, the connecting plug (1) being provided with at least one sealing groove (112), and the shell assembly (3) pressing the airbag (2) against the sealing groove (112) via the sealing ring to achieve sealing.

2. The moisture-proof module for a liquid level sensor according to claim 1, characterized in that: A through hole (13) is provided in the connecting plug (1), and the cable (100) and the air guide tube (200) are passed through the through hole (13). The longitudinal section of the connecting plug (1) is T-shaped, and comprises a first connecting portion (11) and a second connecting portion (12) connected to the first connecting portion (11). The outer diameter of the second connecting portion (12) is greater than the outer diameter of the first connecting portion (11), and the second connecting portion (12) is enclosed in the airbag (2).

3. The moisture-proof module for a liquid level sensor according to claim 2, characterized in that: The housing assembly (3) comprises a shell (32), one end of the shell (32) is connected to the connecting plug (1), an annular step (321) is circumferentially provided inside the end of the shell (32) connected to the connecting plug (1), the shell (32) is sleeved on the connecting plug (1), the inner circumferential surface of the annular step (321) presses the airbag (2) on the first connecting portion (11), and / or the end surface of the annular step (321) presses the airbag (2) on the second connecting portion (12).

4. The moisture-proof module for a liquid level sensor according to claim 3, characterized in that: A signal line (300) is also passed through the cable (100), a first mounting hole (322) is provided on the housing (32), the signal line (300) is passed through the first mounting hole (322), and the signal line (300) and the airbag (2) are separated by the first mounting hole (322).

5. The moisture-proof module for a liquid level sensor according to claim 4, characterized in that: The housing assembly (3) further comprises a cover body (31) connected to the shell (32); the shell (32) and the cover body (31) form a receiving space; the airbag (2) is arranged in the receiving space; a second mounting hole (311) corresponding to the first mounting hole (322) is provided on the cover body (31); a gap (33) is provided axially between the cover body (31) and the shell (32); the receiving space is communicated with the external atmosphere through the gap (33) and the second mounting hole (311).

6. The moisture-proof module for a liquid level sensor according to claim 4, characterized in that: The first connecting portion (11) is provided with an opening (111) in the axial direction, and the signal line (300) extends from the opening (111).

7. The moisture-proof module for a liquid level sensor according to any one of claims 1 to 6, characterized in that: The moisture-proof module further comprises a fixed joint (4), wherein the fixed joint (4) is sleeved on the cable (100), and the fixed joint (4) presses the connecting plug (1) against the cable (100) to achieve a sealed connection between the cable (100) and the connecting plug (1).

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