Probe type liquid level sensor and water tank

By introducing a flow channel and a double-layer sealing ring structure into the probe-type liquid level sensor, the problem of insufficient sealing performance is solved, achieving higher sealing performance and stability, and extending the service life of the sensor.

CN224594029UActive Publication Date: 2026-08-04HENGBO HLDG CO LTD
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
HENGBO HLDG CO LTD
Filing Date
2025-08-21
Publication Date
2026-08-04

AI Technical Summary

Technical Problem

Existing probe-type liquid level sensors have microscopic gaps in their sealing structure, which can lead to media leakage and short circuits, affecting the sensor's sealing performance and reliability.

Method used

A probe-type liquid level sensor was designed, which uses a flow channel to guide the medium to the outside and enhances the sealing performance through a two-layer sealing ring structure to prevent medium leakage.

Benefits of technology

The improved sealing performance of the sensor prevents the medium from entering the insertion cavity, extends the service life of the sensor, and ensures the accuracy of liquid level detection and the stability of system pressure.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model belongs to the technical field of thermal management system, especially point to a kind of probe type liquid level sensor and water tank. Water tank includes water tank main body, liquid level sensor and two first sealing rings, liquid level sensor has sensor shell and two probes, sensor shell has probe mounting part, probe mounting hole for installing probe and flow guide passage for communicating outside are provided on probe mounting part, the flow guide passage communicates probe mounting hole, after the failure of first sealing ring, the medium in the inner cavity of water tank enters the microscopic gap between probe and probe mounting hole under the action of internal pressure, due to the flow guide passage communicates the lower pressure of outside, so that the flow guide passage can directly guide the medium to the outside of plug-in cavity, thereby preventing the medium from continuing to enter the plug-in cavity through the microscopic gap between probe and sensor shell, thereby improving the waterproof performance of plug-in cavity.
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Description

Technical Field

[0001] This utility model belongs to the technical field of thermal management system, specifically referring to a probe-type liquid level sensor and a water tank. Background Technology

[0002] A probe-type liquid level sensor is a precision instrument that detects liquid level by directly contacting the liquid with a probe. In the thermal management system of new energy vehicles, this sensor is typically installed on top of or to the side of the expansion tank. Its core function is to monitor and transmit the liquid level information inside the expansion tank in real time. Because the expansion tank operates under a certain internal pressure, the sensor must not only ensure the accuracy of liquid level detection but also possess excellent sealing performance to prevent internal media leakage and maintain stable system pressure. This dual requirement necessitates a strong focus on the reliability of the sealing structure during the design and manufacturing of the sensor.

[0003] Prior art document CN106289447A discloses a vehicle expansion tank level sensor, which includes a tank housing and a level sensor. The tank housing has a base mounting groove and a conductive rod sealing groove. The level sensor includes two conductive rods and a base for fixing the conductive rods. The base is installed in the base mounting groove. The conductive rods pass through the base and the conductive rod sealing groove and enter the tank housing. An O-ring is provided at the junction of the conductive rods, the base, and the tank housing. The above structure uses an embedded probe-type level sensor. A pin chamber for installing the sensor connector is formed between the base mounting groove and the base. The sensor connector is electrically connected to the conductive rods in the pin chamber.

[0004] Typically, the base is injection molded from insulating materials such as plastic onto the conductive rod. Due to defects in the injection molding process, microscopic gaps inevitably exist at the connection between the metal and plastic parts. In actual use, O-rings may suffer from poor quality, improper installation, or wear. Once the O-ring fails, leakage will occur through these microscopic gaps, allowing the medium (liquid or gaseous) to enter the pin chamber, causing a short circuit between the sensor connector and the conductive rod, thus malfunctioning the level sensor.

[0005] In addition, in the embedded probe-type liquid level sensor, when the O-ring fails, the medium will enter the pin chamber through the gap between the base and the base mounting groove, which will further cause a short circuit between the sensor connector and the conductive rod, resulting in the liquid level sensor malfunction. Utility Model Content

[0006] The purpose of this invention is to provide a probe-type liquid level sensor and water tank that are simple in structure, have good sealing performance, stable detection performance, and long service life.

[0007] The purpose of this utility model is achieved as follows:

[0008] A probe-type liquid level sensor includes: a sensor housing having two probe mounting portions arranged side by side, each probe mounting portion having a probe mounting hole; and two probes, each inserted into a corresponding probe mounting hole and integrally formed with the sensor housing; wherein, the probe mounting portion has a flow channel communicating with the outside, the flow channel communicating with the probe mounting hole, and when the medium enters the microscopic gap between the probe and the probe mounting hole, it can be discharged to the outside through the flow channel.

[0009] The probe-type liquid level sensor of this invention also has the following feature: the width of the flow channel is greater than the diameter of the probe or the probe mounting hole, and the exposed part of the probe is located inside the flow channel, so that the microscopic gap between the probe and the probe mounting hole can be fully connected to the flow channel.

[0010] The probe-type liquid level sensor of this utility model also has the following features: the sensor housing is injection molded from insulating material, and the probe is a metal part; the probe has a plug-in part located on one side of the sensor housing and a sensing part located on the other side of the sensor housing, and an axial limiting part is provided between the sensing part and the plug-in part. The axial limiting part is wrapped in the probe mounting part and is used to limit the axial position of the probe.

[0011] The probe-type liquid level sensor of this invention also has the following feature: the flow channel intersects perpendicularly with the probe mounting hole, and both ends of the flow channel are connected to the outside.

[0012] The probe-type liquid level sensor of this utility model also has the following feature: installation limiting parts are respectively provided at both ends of the sensor housing on one side of the probe mounting part to limit the installation distance of the sensor housing.

[0013] A water tank includes: a water tank body having a sensor mounting portion; a liquid level sensor disposed within the sensor mounting portion and having a sensor housing and two probes; and two first sealing rings respectively fitted onto the two probes for sealing the gap between the probes and the sensor mounting portion; a plug-in cavity for connecting a sensor connector is formed within the sensor housing or between the sensor housing and the sensor mounting portion; wherein the liquid level sensor is the aforementioned probe-type liquid level sensor.

[0014] The water tank of this utility model also has the following features, wherein the sensor mounting part includes: a sensor mounting groove for mounting the sensor housing; and two probe insertion holes for mounting probes, so that the sensing part of the probe extends into the inner cavity of the water tank body; wherein an overflow space is formed between the sensor mounting groove and the sensor housing.

[0015] The bottom of the sensor mounting section has a drain hole that connects to the overflow space; the ends of the flow guide channels are all connected to the overflow space.

[0016] The water tank of this utility model also has the following features: a first sealing groove and a second sealing groove are provided between the probe insertion hole and the sensor mounting groove, the inner diameter of the second sealing groove being larger than the inner diameter of the first sealing groove; the probe mounting part includes a first probe mounting part adapted to the first sealing groove and a second probe mounting part adapted to the second sealing groove, and a flow guiding channel is located on the second probe mounting part; a first sealing ring is provided on the probe near the first probe mounting part, the first sealing ring being used to seal a first gap between the probe and the first sealing groove; a second sealing ring is fitted on the first probe mounting part near the second probe mounting part, the second sealing ring being used to seal a second gap between the first probe mounting part and the second sealing groove.

[0017] The water tank of this utility model also has the following features: the liquid level sensor is inclinedly installed in the sensor mounting part; the second sealing groove is formed by an annular protrusion extending from the bottom of the sensor mounting groove, and the port of the annular protrusion is provided with an inclined guide surface. The lowest position of the inclined guide surface is in an inclined downward state, which is used to guide the medium in the inclined guide surface into the overflow space and out through the drain hole.

[0018] The water tank of this utility model also has the following features: a positioning structure and a fixing structure are provided between the sensor housing and the sensor mounting part; the positioning structure includes a positioning groove provided on one of the components and a positioning protrusion provided on the other component; the fixing structure includes an annular fixing groove provided on one of the components and an annular fixing protrusion provided on the other component.

[0019] The outstanding and beneficial technical effects of this utility model compared to the prior art are:

[0020] 1. In the water tank of this utility model, a first sealing ring is provided between the probe and the sensor mounting part, and a flow channel connecting to the outside is opened on the probe mounting part. When the first sealing ring fails, the medium in the inner cavity of the water tank enters the micro gap between the probe and the probe mounting hole under the action of internal pressure. Since the flow channel connects to the outside with relatively low pressure, the flow channel can directly guide the medium to the outside of the insertion cavity, thereby preventing the medium from continuing to enter the insertion cavity through the micro gap between the probe and the sensor housing, thereby improving the waterproof performance of the insertion cavity.

[0021] 2. The width of the flow channel of this utility model is greater than the diameter of the probe or the probe mounting hole, and the exposed part of the probe can be completely located in the flow channel. This means that the connection between the exposed part and the probe mounting hole can be completely located in the flow channel. This is equivalent to the flow channel structure being able to physically isolate the micro-gap between the probe and the sensor housing, guiding the medium to flow out from the flow channel, and indirectly blocking the medium penetration path.

[0022] 3. The second sealing ring of this utility model, together with the first sealing ring, forms a two-layer sealing structure to prevent the medium from leaking from the gap between the probe mounting part and the sensor mounting part.

[0023] 4. The sensor mounting part of this utility model is inclinedly set on the edge of the water tank cover, and the liquid level sensor is inclinedly set inside the sensor mounting part. The lowest position of the inclined guide surface is in an inclined downward state, which is used to guide the medium of the second sealing groove into the overflow space between the annular protrusion and the sensor mounting groove. Attached Figure Description

[0024] Figure 1 This is a structural schematic diagram of the water tank of this utility model.

[0025] Figure 2 This is an exploded view of the water tank of this utility model.

[0026] Figure 3 This is a schematic diagram of the liquid level sensor of this utility model.

[0027] Figure 4 This is a schematic diagram of the sensor mounting part of this utility model.

[0028] Figure 5 This is one of the cross-sectional views of the mounting location of the liquid level sensor of this utility model.

[0029] Figure 6 This is the second sectional view of the mounting location of the liquid level sensor of this utility model.

[0030] The meaning of the labels in the diagram:

[0031] 1. Sensor housing; 2. Probe; 3. Water tank body; 4. First sealing ring; 5. Second sealing ring;

[0032] Probe mounting part 11; First probe mounting part 111; Second probe mounting part 112; Flow guiding channel 12; Insertion cavity 13; Positioning protrusion 14; Annular fixing protrusion 15; Side wall part 16; Mounting buckle 161; Mounting limiting part 17.

[0033] Exposed part 21; Insertion part 22; Sensing part 23; Axial limiting part 24;

[0034] Sensor mounting part 31; sensor mounting groove 311; probe insertion hole 312; overflow space 313; drain hole 314; first sealing groove 315; second sealing groove 316; inclined guide surface 3161; positioning groove 317; annular fixing groove 318; reinforcing rib 319;

[0035] Liquid level sensor 100. Detailed Implementation

[0036] The present invention will be further described below with reference to specific embodiments:

[0037] Example 1:

[0038] like Figure 1 , 2 As shown, a water tank with a probe-type liquid level sensor includes a tank body 3 and a liquid level sensor 100. In this embodiment, the tank body 3 is mainly used in a thermal management system for storing a medium, typically an aqueous solution of ethylene glycol or propylene glycol. The liquid level sensor primarily detects the liquid level height within the tank, providing real-time liquid level data and reminding the user to replenish the medium in a timely manner.

[0039] Specifically, the water tank body 3 has a water tank top cover with a water inlet and a water tank bottom shell (not shown in the figure). The two are sealed together to form a water tank cavity for containing the medium. In this embodiment, a sensor mounting part 31 is inclinedly provided on the edge of the water tank top cover. The liquid level sensor 100 is installed in the sensor mounting part 31 and is used to detect the liquid level height in the water tank cavity.

[0040] like Figure 3 As shown, the liquid level sensor 100 includes a sensor housing 1, two probes 2, and a sensor connector (not shown in the figure).

[0041] The sensor housing 1 has a main body, two probe mounting portions 11 arranged side-by-side on one side of the main body, and a side wall portion 16 extending along the other edge of the main body. The main body and the side wall portion 16 form an open-ended insertion cavity 13 (i.e., a pin chamber). The probe mounting portions 11 have probe mounting holes, and two probes 2 are respectively inserted into their corresponding probe mounting holes and formed onto the sensor housing 1. Specifically, the probes 2 are metal parts, and the sensor housing 1 is made of insulating materials such as plastic. The sensor housing 1 is formed together with the two probes 2 through a secondary injection molding process.

[0042] like Figure 2 As shown, the probe 2 has a plug-in portion 22 located on one side of the sensor housing 1, a sensing portion 23 located on the other side of the sensor housing 1, and an axial limiting portion 24 disposed between the sensing portion 23 and the plug-in portion 22. The axial limiting portion 24 is enclosed in the probe mounting portion 11 and is used to limit the axial position of the probe 2.

[0043] Specifically, the insertion part 22 is flat and mainly located within the insertion cavity 13, with a portion located within the sensor housing 1; the axial limiting part 24 is a flat protrusion or groove located within the probe mounting part 11, used to prevent the probe 2 from axially moving with the sensor housing 1 and to increase the fixing strength; the sensing part 23 extends out of the sensor housing 1 and can enter the inner cavity of the water tank through the sensor mounting part 31, the length of the sensing part 23 being selected according to the required depth of the inner cavity of the water tank. In this embodiment, the probe 2 is made of a circular metal rod, and the insertion part 22 and the axial limiting part 24 are pressed to form a flat structure, with one side of the axial limiting part 24 having a convex shape (e.g., Figure 5 As shown), the cross-section on the other side is groove-shaped (as shown). Figure 6 As shown in the figure, the outer diameters of the remaining parts are basically the same.

[0044] In addition, an installation structure for mounting a sensor connector is provided on the outer side of the side wall portion 16. The installation structure may be a mounting clip 161, a threaded portion, etc. The connector of the sensor connector is inserted into the sensor housing 1 through the corresponding installation structure and can be electrically connected to the insertion portion 22 of the probe 2.

[0045] like Figure 4 As shown, the sensor mounting part 31 includes a sensor mounting groove 311, two probe insertion holes 312, and a first sealing groove 315 and a second sealing groove 316 located between the probe insertion holes 312 and the sensor mounting groove 311.

[0046] A probe insertion part is provided on the inner side of the water tank cover. The probe insertion part has a probe insertion hole 312 that connects to the sensor mounting groove 311. This hole is used to install the probe 2 and allow the sensing part 23 of the probe 2 to extend into the inner cavity of the water tank body 3. The sensor mounting groove 311 is used to install and fix the sensor housing 1. The sensor mounting groove 311 is formed by a mounting groove wall extending from the water tank cover. The cross-section of the mounting groove wall is generally rectangular, with three sides intersecting perpendicularly, and the other side transitioning arc-shaped to form an arc-shaped connecting sidewall. The shape of the sensor mounting groove 311 is basically consistent with the outer contour of the sensor housing 1, which can play a foolproof role and prevent incorrect installation. Preferably, several reinforcing ribs 319 are vertically provided on the inner and / or outer sides of the mounting groove wall to increase the strength of the mounting groove wall.

[0047] like Figure 5As shown, to facilitate the installation and fixation of the sensor housing 1, preferably, a positioning structure and a fixing structure are provided between the sensor housing 1 and the sensor mounting part 31. The positioning structure includes a positioning groove 317 provided on one of the components (sensor mounting part 31 or sensor housing 1) and a positioning protrusion 14 provided on the other component (sensor housing 1 or sensor mounting part 31); the fixing structure includes an annular fixing groove 318 provided on one of the components and an annular fixing protrusion 15 provided on the other component.

[0048] In this embodiment, a positioning groove 317 is provided on the arc-shaped connecting sidewall, and an annular fixing groove 318 is provided on the inner edge of the groove opening of the sensor mounting groove 311. The annular fixing groove 318 and the positioning groove 317 intersect. Correspondingly, a positioning protrusion 14 adapted to the positioning groove 317 and an annular fixing protrusion 15 adapted to the annular fixing groove 318 are provided on the outer side wall of the main body of the sensor housing 1. The positioning protrusion 14 is located on one side of the annular fixing protrusion 15. When the two probes of the liquid level sensor 100 are respectively inserted into the corresponding probe insertion holes 312, the sensor housing 1 presses the annular fixing protrusion 15 into the annular fixing groove 318 of the sensor mounting groove 311 with an interference / clearance fit. At the same time, the positioning structure enters the sensor mounting groove 311 and performs axial height positioning, thereby installing the liquid level sensor 100 on the water tank body 3 and achieving stable fixation.

[0049] In another embodiment, the positioning groove 317 and / or the annular fixing groove 318 can also be provided on the sensor housing 1, and correspondingly, the positioning protrusion 14 and / or the annular fixing protrusion 15 are provided on the sensor mounting groove 311.

[0050] Preferably, in order to prevent the sensor housing 1 from being over-inserted, mounting limiting parts 17 are respectively provided at both ends of the sensor housing 1 on the probe mounting part 11 side. When the sensor housing 1 is inserted into the sensor mounting groove 311, the mounting limiting part 17 is located inside the sensor mounting groove 311 and can abut against the bottom surface of the sensor mounting groove 311, thereby further limiting the installation distance between the sensor housing 1 and the sensor mounting groove 311, while ensuring the reliability of the fixing structure.

[0051] In this embodiment, a first sealing groove 315 and a second sealing groove 316 are provided between the probe insertion hole 312 and the sensor mounting groove 311. Figure 5 , 6As shown, the inner diameter of the first sealing groove 315 is larger than the inner diameter of the probe insertion hole 312, and the two are transitioned by a first inclined surface. The first inclined surface is used to quickly guide the probe 2 into the probe insertion hole 312. The probe mounting part 11 has a first probe mounting part 111 adapted to the first sealing groove 315. The outer diameter of the first probe mounting part 111 is larger than the outer diameter of the probe 2. A first sealing ring 4 is respectively fitted on the two probes 2. The first sealing ring 4 is close to the end face of the first probe mounting part 111. The first probe mounting part 111 can press the first sealing ring 4 into the first sealing groove 315, so that the first sealing ring 4 can seal the first gap between the probe 2 and the first sealing groove 315, reducing the risk of the medium in the water tank cavity leaking from the first gap.

[0052] It should be noted that the sensor housing 1 is formed by injection molding with the two probes 2. Due to the current limitations of the secondary molding technology of metal materials and plastics, there will be a certain microscopic gap between the probes 2 and the sensor housing 1. That is, there is a microscopic gap between the inner wall of the probe mounting hole and the outer wall of the probe 2. If the medium leaks from the gap between the probe 2 and the first sealing groove 315, under the action of the internal pressure of the water tank cavity, the medium may enter the plug cavity 13 through the microscopic gap, causing water to enter the plug structure between the probe 2 and the sensor connector and short-circuit.

[0053] Therefore, such as Figure 5 , 6 As shown, the probe mounting part 11 has a flow channel 12 that connects to the outside. The flow channel 12 connects to the probe mounting hole. Specifically, the flow channel 12 is preferably a flow hole that intersects the probe mounting hole perpendicularly, and one or both ends of the flow channel 12 connect to the outside of the sensor housing 1.

[0054] The portion of probe 2 located within the flow channel 12 is defined as exposed portion 21. Preferably, the width of the flow channel 12 is greater than the diameter of probe 2 or probe mounting hole, so that exposed portion 21 can be entirely located within the flow channel 12. This allows the connection portion formed by the exposed portion 21 and the probe mounting hole to be entirely located within the flow channel 12, meaning that the microscopic gap formed between probe 2 and sensor housing 1 can be fully connected to the flow channel 12.

[0055] When leakage occurs at the first sealing ring 4, a portion of the medium enters the sensor mounting groove 311 through the gap between the first probe mounting part 111 and the first sealing groove part 315. Another portion of the medium (mainly gaseous medium) can enter through the micro-gap between the probe 2 and the sensor housing 1. At this time, the flow channel 12 can directly guide the medium to the outside of the insertion cavity 13, thereby preventing the medium from continuing to enter the insertion cavity 13 through the micro-gap between the probe 2 and the sensor housing 1, and improving the waterproof performance of the insertion cavity 13.

[0056] Preferably, an overflow space 313 is formed between the sensor mounting groove 311 and the sensor housing 1. The ends of the guide channel 12 are all connected to the overflow space 313. A drain hole 314 connected to the overflow space 313 is provided at the bottom of the sensor mounting part 31. The medium generated by the guide channel 12 and the medium leaked between the first probe mounting part 111 and the first sealing groove part 315 can be discharged to the outside of the water tank through the overflow space 313 and the drain hole 314.

[0057] In another embodiment, a second sealing groove 316 is provided between the probe insertion hole 312 and the sensor mounting groove 311. The inner diameter of the second sealing groove 316 is larger than the inner diameter of the first sealing groove 315, and it is located between the first sealing groove 315 and the sensor mounting groove 311.

[0058] like Figure 5 As shown, the second sealing groove 316 is formed by an annular protrusion protruding from the bottom surface of the sensor mounting groove 311. The probe mounting part 11 also includes a second probe mounting part 112 adapted to the second sealing groove 316, and the flow channel 12 is located on the second probe mounting part 112.

[0059] The outer diameter of the second probe mounting part 112 is larger than that of the first probe mounting part 111. A second sealing ring 5 is fitted on the first probe mounting part 111. The second sealing ring 5 is close to the end face of the second probe mounting part 112. The second probe mounting part 112 can press the second sealing ring 5 into the second sealing groove 316, so that the second sealing ring 5 can seal the second gap between the first probe mounting part 111 and the second sealing groove 316, thereby forming a two-layer sealing structure together with the first sealing ring 4 to prevent the medium from leaking from the gap between the probe mounting part 11 and the sensor mounting part 31.

[0060] Preferably, the annular protruding port is provided with a sloping guide surface 3161, which guides the second probe mounting part 112 into the second sealing groove part 316. At the same time, the connection between the second sealing groove part 316 and the first sealing groove part 315 is transitioned by a second inclined surface, which guides the first probe mounting part 111 into the first sealing groove part 315 for easy installation.

[0061] Preferably, such as Figure 6 As shown, in order to reduce the height of the sensor mounting part 31, the port portion of the flow channel 12 is located in the space formed by the inclined guide surface 3161, and only a flow gap smaller than the inner diameter of the flow channel 12 is reserved between the annular protrusion and the sensor housing 1, so that the medium of the flow channel 12 can enter the overflow space 313.

[0062] like Figure 1As shown, the sensor mounting part 31 is inclinedly disposed on the edge of the water tank cover, and the liquid level sensor 100 is inclinedly disposed inside the sensor mounting part 31. The lowest position of the inclined guide surface 3161 is in a downward inclined state, which is used to guide the medium in the inclined guide surface 3161 into the overflow space 313 between the annular protrusion and the sensor mounting groove 311. When the medium discharged from the guide channel 12 enters the inclined guide surface 3161, it will automatically flow into the overflow space 313, and finally be discharged to the outside of the water tank through the drain hole 314.

[0063] In this embodiment, the side wall portion 16 is located outside the sensor mounting groove 311, and the insertion cavity 13 is separately formed inside the sensor housing 1 and is not connected to the first gap, the second gap, and the overflow space 313. Therefore, it will not be affected by the medium leakage from the first sealing ring 4 and the second sealing ring 5.

[0064] Furthermore, the solution in this embodiment can also be used in other application scenarios that require detection of internal liquid level.

[0065] Example 2:

[0066] This embodiment is basically the same as Embodiment 1, except that: the sensor housing 1 does not have a side wall portion 16, and a plug-in cavity 13 for connecting the sensor connector is formed between the sensor housing 1 and the sensor mounting portion 31.

[0067] Specifically, the sensor housing 1 of this embodiment has a sheet-like housing body and two probe mounting parts 11 arranged side by side on one side of the housing body. Two probes 2 are respectively fixed to the sensor housing 1 through the probe mounting parts 11.

[0068] The sensor mounting section 31 includes a sensor mounting groove 311, two probe insertion holes 312, and a first sealing groove 315 and a second sealing groove 316 located between the probe insertion holes 312 and the sensor mounting groove 311.

[0069] The sensor mounting groove 311 is formed by a mounting groove wall extending on the water tank cover. The height of the mounting groove wall is higher than that of Embodiment 1, which can completely cover the sensor housing 1. When the two probes 2 are inserted into the probe insertion hole 312, the sensor housing 1 is installed at the bottom of the sensor mounting groove 311, so that the housing body and the mounting groove wall form a plug-in cavity 13. An installation structure for installing the sensor connector is provided on the inner wall of the mounting groove wall. The connector of the sensor connector is plugged in through the corresponding installation structure, thereby realizing electrical connection with the plug-in part 22 of the probe 2.

[0070] The probe mounting portion 11 has a first probe mounting portion 111 adapted to the first sealing groove portion 315 and a second probe mounting portion 112 adapted to the second sealing groove portion 316. Two probes 2 are respectively fitted with a first sealing ring 4, which is close to the end face of the first probe mounting portion 111. The first probe mounting portion 111 can press the first sealing ring 4 into the first sealing groove portion 315, so that the first sealing ring 4 can seal the first gap between the probe 2 and the first sealing groove portion 315. A second sealing ring 5 is fitted on the first probe mounting portion 111, which is close to the end face of the second probe mounting portion 112. The second probe mounting portion 112 can press the second sealing ring 5 into the second sealing groove portion 316, so that the second sealing ring 5 can seal the second gap between the first probe mounting portion 111 and the second sealing groove portion 316.

[0071] This embodiment uses a two-layer sealing structure of the first sealing ring 4 and the second sealing ring 5 to prevent the medium from leaking from the gap between the probe mounting part 11 and the sensor mounting part 31.

[0072] At the same time, a third sealing ring needs to be provided between the sensor housing 1 and the sensor mounting groove 311 to seal the third gap between the insertion cavity 13 and the overflow space 313, so as to prevent the medium in the overflow space 313 from entering the insertion cavity 13.

[0073] The above embodiments are merely preferred embodiments of the present utility model and are not intended to limit the scope of protection of the present utility model. Therefore, all equivalent changes made to the structure, shape, and principle of the present utility model should be covered within the scope of protection of the present utility model.

Claims

1. A probe-type liquid level sensor characterized by, include: The sensor housing (1) has two probe mounting portions (11) arranged side by side, and each probe mounting portion (11) has a probe mounting hole; and Two probes (2) are respectively inserted into the corresponding probe mounting holes and integrally formed with the sensor housing (1); The probe mounting part (11) is provided with a flow channel (12) that connects to the outside. The flow channel (12) connects to the probe mounting hole. When the medium enters the micro gap between the probe (2) and the probe mounting hole, it can be discharged to the outside through the flow channel (12).

2. The probe-type liquid level sensor according to claim 1, characterized in that: wherein The width of the flow channel (12) is greater than the diameter of the probe (2) or the probe mounting hole. The exposed part (21) of the probe (2) is located inside the flow channel (12), so that the microscopic gap between the probe (2) and the probe mounting hole can be fully connected to the flow channel (12).

3. The probe-type liquid level sensor according to claim 1, characterized in that: wherein The sensor housing (1) is injection molded from insulating material, and the probe (2) is a metal part; The probe (2) has a plug-in portion (22) located on one side of the sensor housing (1) and a sensing portion (23) located on the other side of the sensor housing (1). An axial limiting portion (24) is also provided between the sensing portion (23) and the plug-in portion (22). The axial limiting portion (24) is wrapped inside the probe mounting portion (11) and is used to limit the axial position of the probe (2).

4. A probe-type liquid level sensor according to any one of claims 1-3, characterized in that: wherein, The flow channel (12) intersects perpendicularly with the probe mounting hole, and both ends of the flow channel (12) are connected to the outside.

5. A probe-type liquid level sensor according to any one of claims 1-3, characterized in that: wherein The sensor housing (1) on one side of the probe mounting part (11) is provided with mounting limiting parts (17) at both ends to limit the mounting distance of the sensor housing (1).

6. A water tank characterized by include: The main body of the water tank (3) has a sensor mounting part (31); A liquid level sensor (100) is disposed within the sensor mounting portion (31) and has a sensor housing (1) and two probes (2); and Two first sealing rings (4) are respectively fitted onto the two probes (2) to seal the gap between the probes (2) and the sensor mounting part (31); The liquid level sensor (100) is a probe-type liquid level sensor as described in any one of claims 1-5.

7. A water tank according to claim 6, Its features are: The sensor mounting part (31) includes: A sensor mounting slot (311) for mounting the sensor housing (1); and Two probe insertion holes (312) are used to install the probe (2) so that the sensing part (23) of the probe (2) extends into the inner cavity of the water tank body (3); An overflow space (313) is formed between the sensor mounting slot (311) and the sensor housing (1); The bottom of the sensor mounting part (31) is provided with a drain hole (314) that connects to the overflow space (313); The ends of the flow guiding channels (12) are all connected to the overflow space (313).

8. A water tank according to claim 7, characterized in that: wherein, A first sealing groove (315) and a second sealing groove (316) are provided between the probe insertion hole (312) and the sensor mounting groove (311), and the inner diameter of the second sealing groove (316) is larger than the inner diameter of the first sealing groove (315). The probe mounting part (11) includes a first probe mounting part (111) adapted to the first sealing groove part (315) and a second probe mounting part (112) adapted to the second sealing groove part (316), and the flow channel (12) is located on the second probe mounting part (112); A first sealing ring (4) is provided on the probe (2) near the first probe mounting part (111), and the first sealing ring (4) is used to seal the first gap between the probe (2) and the first sealing groove (315); A second sealing ring (5) is fitted on the first probe mounting part (111) near the second probe mounting part (112). The second sealing ring (5) is used to seal the second gap between the first probe mounting part (111) and the second sealing groove (316).

9. A water tank according to claim 8, characterized in that: wherein, The liquid level sensor (100) is inclinedly disposed inside the sensor mounting part (31); The second sealing groove (316) is formed by an annular protrusion extending from the bottom of the sensor mounting groove (311). The port of the annular protrusion is provided with a sloping guide surface (3161). The lowest position of the sloping guide surface (3161) is in a downward sloping state, which is used to guide the medium in the sloping guide surface (3161) into the overflow space (313) and out from the drain hole (314).

10. A water tank according to any one of claims 6-9, characterized in that: wherein A positioning structure and a fixing structure are provided between the sensor housing (1) and the sensor mounting part (31); The positioning structure includes a positioning groove (317) provided on one of the components and a positioning protrusion (14) provided on the other component; The fixing structure includes an annular fixing groove (318) provided on one of the components and an annular fixing protrusion (15) provided on the other component.