Bipolar probe liquid level meter for hot tank of water dispenser and water dispenser

Abstract

A bipolar probe liquid level meter for a hot tank of a water dispenser comprises a low liquid level electrode, a high liquid level electrode, a first insulating tube, a second insulating tube, a conductive fixing ring and a control circuit board, and the low liquid level electrode comprises a detection end and a signal transmission end; the high-liquid-level electrode is of a tubular structure and is connected to the signal transmission end in a sleeving mode, and an insulation area is formed between the high-liquid-level electrode and the low-liquid-level electrode; the first insulating tube is positioned in the insulating area and is propped against the low-liquid-level electrode and the high-liquid-level electrode; the second insulating tube sleeves the high-liquid-level electrode, and the inner surface of the second insulating tube abuts against the outer surface of the high-liquid-level electrode; the conductive fixing ring is connected and electrically conducted with the hot tank shell of the water dispenser, the conductive fixing ring sleeves the second insulating tube, and the inner surface of the conductive fixing ring abuts against the outer surface of the second insulating tube; the control circuit board comprises a low liquid level control circuit connected with the low liquid level electrode, the conductive fixing ring and the water dispenser controller, and a high liquid level control circuit connected with the high liquid level electrode, the conductive fixing ring and the water dispenser controller. The utility model further discloses a water dispenser comprising the bipolar probe liquid level meter.

Description

Technical Field

[0001] The utility model relates to the technical field of water dispensers, in particular to a bipolar probe liquid level meter used for a hot tank of a water dispenser and a water dispenser. Background Art

[0002] The liquid level meter is an important part of drinking water equipment. It is used to monitor the liquid level height of the water tank of the drinking water equipment, so that the drinking water equipment responds and stops water intake when the liquid level is high to prevent water overflow, and responds and adds water to the water tank when the liquid level is low to prevent the equipment from drying out or being idle. At present, the liquid level meter of the drinking water dispenser on the market detects the high liquid level and low liquid level of the water tank respectively by setting a high liquid level probe and a low liquid level probe. The two probes are independently set stainless steel probes. When assembling the equipment, one probe needs to be installed at the high position and the other at the low position of the water tank. The equipment assembly workload is large. The use of two probes will also increase the processing cost of the drinking water dispenser liquid level meter and the cost of the drinking water dispenser liquid level detection. Utility Model Content

[0003] Based on this, it is necessary to provide a bipolar probe level gauge and a water dispenser for a hot tank of a water dispenser that are easy to assemble and low in cost in order to address the above-mentioned shortcomings.

[0004] A bipolar probe level gauge for a hot tank of a water dispenser, comprising:

[0005] A low liquid level electrode, the low liquid level electrode comprising a detection end and a signal transmission end;

[0006] A high liquid level electrode, which is in a tubular structure, is sleeved on the signal transmission end of the low liquid level electrode, and an insulating area is formed between the high liquid level electrode and the low liquid level electrode;

[0007] a first insulating tube, wherein the first insulating tube is sleeved on the low liquid level electrode and is located in the insulating area, the inner surface of the first insulating tube abuts against the outer surface of the low liquid level electrode, and the outer surface of the first insulating tube abuts against the inner surface of the high liquid level electrode;

[0008] A second insulating tube, wherein the second insulating tube is sleeved on the high liquid level electrode, and the inner surface of the second insulating tube abuts against the outer surface of the high liquid level electrode;

[0009] A conductive fixing ring, the conductive fixing ring is fixedly connected to the outer shell of the hot tank of the water dispenser and is electrically conductive, the conductive fixing ring is sleeved on the second insulating tube and the inner surface of the conductive fixing ring abuts against the outer surface of the second insulating tube;

[0010] A control circuit board, the control circuit board comprising a low liquid level control circuit electrically connected to the low liquid level electrode, the conductive fixing ring and the water dispenser controller, and a high liquid level control circuit electrically connected to the high liquid level electrode, the conductive fixing ring and the water dispenser controller;

[0011] The low liquid level control circuit comprises a first voltage divider circuit connected to a power supply, a first filter circuit connected to the first voltage divider circuit, a first voltage comparison circuit connected to the first filter circuit, and a first drive circuit connected to the first voltage comparison circuit, the low liquid level electrode and the conductive fixing ring are both connected to the connection line between the first voltage divider circuit and the first filter circuit, and the output end of the first drive circuit is connected to the water dispenser controller;

[0012] The high liquid level control circuit includes a second voltage divider circuit connected to a power supply, a second filter circuit connected to the second voltage divider circuit, a second voltage comparison circuit connected to the second filter circuit, and a second drive circuit connected to the second voltage comparison circuit. The high liquid level electrode and the conductive fixed ring are both connected to the connecting line between the second voltage divider circuit and the second filter circuit, and the output end of the second drive circuit is connected to the water dispenser controller.

[0013] In one of the embodiments, an end of the first insulating tube adjacent to the detection end extends from the insulating area and forms a protective portion.

[0014] In one embodiment, the second insulating tube is sleeved on one end of the high liquid level electrode adjacent to the signal transmission end, the length of the high liquid level electrode is greater than the length of the second insulating tube, and one end of the high liquid level electrode adjacent to the detection end forms a high liquid level detection portion on one side of the second insulating tube.

[0015] In one embodiment, the conductive fixing ring is a hollow bolt.

[0016] In one embodiment, the low liquid level electrode and the high liquid level electrode are both made of stainless steel.

[0017] In one embodiment, the first insulating tube and the second insulating tube are both ceramic insulating tubes.

[0018] In one embodiment, the first voltage-dividing circuit includes a first voltage-dividing resistor and a second voltage-dividing resistor respectively connected to a power supply and arranged in parallel, and a third voltage-dividing resistor connected in series with the second voltage-dividing resistor; the first filter circuit includes a first ceramic filter capacitor and a second ceramic filter capacitor; the first voltage comparison circuit includes a first voltage comparator; and the first drive circuit includes a first Darlington transistor.

[0019] In one embodiment, the second voltage-dividing circuit includes an eleventh voltage-dividing resistor and a twelfth voltage-dividing resistor respectively connected to the power supply and arranged in parallel, and a thirteenth voltage-dividing resistor connected in series with the twelfth voltage-dividing resistor; the second filter circuit includes an eleventh ceramic filter capacitor and a twelfth ceramic filter capacitor; the second voltage comparison circuit includes a second voltage comparator; and the second drive circuit includes a second Darlington transistor.

[0020] The utility model also discloses a water dispenser, which comprises the above-mentioned bipolar probe liquid level meter.

[0021] In the implementation of the bipolar probe liquid level meter and water dispenser for the hot tank of a water dispenser of the utility model, the high liquid level electrode is processed into a tubular structure and sleeved on the low liquid level electrode, the high liquid level electrode is insulated and separated from the low liquid level electrode by a first insulating tube, and the high liquid level electrode, the conductive fixing ring, the hot tank shell and the high liquid level control circuit form a loop for detecting the high liquid level, and the low liquid level electrode, the conductive fixing ring, the hot tank shell and the low liquid level control circuit form a loop for detecting the low liquid level. When the liquid level in the hot tank is at different height levels, the low liquid level control circuit The circuit and the high liquid level control circuit send different level signals to the water dispenser controller, so that the water dispenser controller controls the equipment to perform corresponding actions. The low liquid level electrode and the high liquid level electrode are combined to form a probe. In this way, when detecting the liquid level in the hot tank of the water dispenser, only one liquid level meter and a single probe need to be installed to meet the detection of high and low liquid levels of the water dispenser, reducing the equipment assembly workload and assembly difficulty during the liquid level detection of the water dispenser. The setting of a single probe is conducive to reducing the processing cost of the liquid level meter and the liquid level detection cost of the water dispenser. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of a bipolar probe liquid level gauge in one embodiment of the utility model;

[0023] Figure 2 It is a schematic cross-sectional structure diagram of a bipolar probe liquid level gauge in one embodiment of the utility model;

[0024] Figure 3 A circuit module diagram of a low liquid level control circuit in one embodiment of the utility model;

[0025] Figure 4 A circuit module diagram of a high liquid level control circuit in one embodiment of the utility model;

[0026] Figure 5 This is a circuit schematic diagram of a low liquid level control circuit in one embodiment of the utility model;

[0027] Figure 6 The figure is a circuit schematic diagram of a high liquid level control circuit in one embodiment of the utility model. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0029] Please combine Figure 1-3 The utility model discloses a bipolar probe liquid level gauge for a hot tank of a water dispenser, which is easy to assemble and has low cost. The bipolar probe liquid level gauge comprises a low liquid level electrode 100, a high liquid level electrode 200, a first insulating tube 300, a second insulating tube 400, a conductive fixing ring 500 and a control circuit board 600. The low liquid level electrode 100 comprises a detection end and a signal transmission end, and the length of the low liquid level electrode 100 is greater than that of the high liquid level electrode 200. When the bipolar probe liquid level gauge is installed on the hot tank of the water dispenser, the detection end of the low liquid level electrode 100 is located below the signal transmission end, and the detection end is adjacent to the bottom of the hot tank so as to respond when the liquid level is low; the high liquid level electrode 200 is adjacent to the top of the hot tank so as to respond when the liquid level is high.

[0030] In this embodiment, the high liquid level electrode 200 is a tubular structure, the high liquid level electrode 200 is sleeved on the signal transmission end of the low liquid level electrode 100, and an insulating area is formed between the high liquid level electrode 200 and the low liquid level electrode 100, the first insulating tube 300 is sleeved on the low liquid level electrode 100 and is located in the insulating area, the inner surface of the first insulating tube 300 abuts against the outer surface of the low liquid level electrode 100, and the outer surface of the first insulating tube 300 abuts against the inner surface of the high liquid level electrode 200. In other words, the inner surface of the high liquid level electrode 200 does not contact the outer surface of the low liquid level electrode 100, and the two are separated by the first insulating tube 300 to achieve electrical isolation. The second insulating tube 400 is sleeved on the high liquid level electrode 200, and the inner surface of the second insulating tube 400 abuts against the outer surface of the high liquid level electrode 200. The conductive fixing ring 500 is fixedly connected to the outer shell of the hot tank of the water dispenser and is electrically conductive. The conductive fixing ring 500 is sleeved on the second insulating tube 400, and the inner surface of the conductive fixing ring 500 abuts against the outer surface of the second insulating tube 400. In other words, the conductive fixing ring 500 is separated from the high liquid level electrode 200 by the second insulating tube 400 to achieve electrical isolation. In this embodiment, the conductive fixing ring 500 is used to fix the bipolar probe liquid level gauge on the top cover of the hot tank of the water dispenser on the one hand, and on the other hand, the conductive fixing ring 500 also forms a conductor together with the outer shell of the hot tank, so that under the preset liquid level, the high liquid level electrode 200 and the low liquid level electrode 100 are respectively conductive with the control circuit board 600. Preferably, the conductive fixing ring 500 is a hollow bolt, and the conductive fixing ring 500 and the hot tank shell are both made of stainless steel. Correspondingly, the low liquid level electrode 100 and the high liquid level electrode 200 are both made of stainless steel. In this way, the conductive fixing ring 500, the hot tank shell, the low liquid level electrode 100 and the high liquid level electrode 200 can avoid the rust problem caused by long-term contact with water while providing an electrical connection, prevent the pollution of drinking water, and ensure the conductive effect. In addition, in this embodiment, the first insulating tube 300 and the second insulating tube 400 are both ceramic insulating tubes. The ceramic insulating tube is stable in nature, not easy to deform, and has a long service life, which ensures the reliability of insulation between the low liquid level electrode 100 and the high liquid level electrode 200, and between the high liquid level electrode 200 and the conductive fixing ring 500.

[0031] The control circuit board 600 includes a low liquid level control circuit 610 electrically connected to the low liquid level electrode 100, the conductive fixing ring 500 and the water dispenser controller, and a high liquid level control circuit 620 electrically connected to the high liquid level electrode 200, the conductive fixing ring 500 and the water dispenser controller. When the bipolar probe liquid level gauge is installed, the control circuit board 600 is arranged on the outside of the hot tank to prevent the control circuit board 600 from contacting the water in the hot tank, thereby causing damage to the control circuit board 600. In this embodiment, the control circuit board 600 is provided with a waterproof protective shell, which is used to encapsulate the control circuit board 600 to prevent the control circuit board 600 from being bumped or infiltrated with water. The low liquid level control circuit 610 includes a first voltage divider circuit 611 connected to a power source, a first filter circuit 612 connected to the first voltage divider circuit 611, a first voltage comparison circuit 613 connected to the first filter circuit 612, and a first drive circuit 614 connected to the first voltage comparison circuit 613. The low liquid level electrode 100 and the conductive fixing ring 500 are both connected to the connection line between the first voltage divider circuit 611 and the first filter circuit 612. The output end of the first drive circuit 614 is connected to the water dispenser controller. The high liquid level control circuit 620 includes a second voltage divider circuit 621 connected to a power source, a second filter circuit 622 connected to the second voltage divider circuit 621, a second voltage comparison circuit 623 connected to the second filter circuit 622, and a second drive circuit 624 connected to the second voltage comparison circuit 623. The high liquid level electrode 200 and the conductive fixing ring 500 are both connected to the connection line between the second voltage divider circuit 621 and the second filter circuit 622. The output end of the second drive circuit 624 is connected to the water dispenser controller.

[0032] In this embodiment, the conductive fixing ring 500 is fixed on the outer shell of the hot tank of the water dispenser and the conductive fixing ring 500 is electrically connected to the outer shell. When the liquid level in the hot tank rises to the point where the detection end of the low liquid level electrode 100 contacts the water, the low liquid level electrode 100 is electrically connected to the low liquid level control circuit 610. At the same time, the low liquid level electrode 100 is also electrically connected to the outer shell of the hot tank through water as a conductor, thereby achieving conduction between the low liquid level electrode 100 and the conductive fixing ring 500. In this way, the low liquid level electrode 100, the low liquid level control circuit 610, and the conductive fixing ring 500 form a loop and send an electrical signal to the controller of the water dispenser. Similarly, when the liquid level in the hot tank rises to the point where the high liquid level electrode 200 contacts the water, the high liquid level electrode 200 is electrically connected to the high liquid level control circuit 620. At the same time, the high liquid level electrode 200 is also electrically connected to the outer shell of the hot tank through water as a conductor, thereby achieving conduction between the high liquid level electrode 200 and the conductive fixing ring 500. In this way, the high liquid level electrode 200, the high liquid level control circuit 620, and the conductive fixing ring 500 form a loop and send an electrical signal to the controller of the water dispenser.

[0033] When the bipolar probe liquid level gauge is in use, when the liquid level in the hot tank does not reach the minimum liquid level required for heating the water dispenser, the low liquid level control circuit 610 outputs a high level signal. When the water level in the hot tank rises to the point where the detection end of the low liquid level electrode 100 contacts the water, the low liquid level electrode 100 forms a loop with the conductive fixing ring 500 and the low liquid level control circuit 610, and the low liquid level control circuit 610 outputs a low level signal, and the high liquid level control circuit 620 outputs a high level signal. When the water level continues to rise to the point where the high liquid level electrode 200 contacts the water, the conductive fixing ring 500 contacts the high liquid level electrode 200 and the high liquid level control circuit 620, and the high liquid level control circuit 620 outputs a low level signal, so that the controller of the water dispenser controls the water pump to stop adding water.

[0034] In one embodiment, one end of the first insulating tube 300 adjacent to the detection end extends from the insulating area and forms a protective portion, which is used to receive the end of the high liquid level electrode 200 to prevent the high liquid level electrode 200 and the end of the first insulating tube 300 from breaking due to excessive shear force, thereby extending the service life of the high liquid level electrode 200. In addition, in this embodiment, the second insulating tube 400 is sleeved on one end of the high liquid level electrode 200 adjacent to the signal transmission end, the length of the high liquid level electrode 200 is greater than the length of the second insulating tube 400, and one end of the high liquid level electrode 200 adjacent to the detection end forms a high liquid level detection portion on one side of the second insulating tube 400, which is used to provide a portion where the high liquid level probe contacts water. In other words, the high liquid level detection portion is used to provide a conductive portion between the high liquid level electrode 200 and the conductive fixing ring 500.

[0035] Please combine Figure 1-6In this embodiment, the first voltage divider circuit 611 includes a first voltage divider resistor R1 and a second voltage divider resistor R2 respectively connected to the power supply and arranged in parallel, and a third voltage divider resistor R3 connected in series with the second voltage divider resistor R2; the first filter circuit 612 includes a first ceramic filter capacitor C1 and a second ceramic filter capacitor C2; the first voltage comparison circuit 613 includes a first voltage comparator IC1-1; the first drive circuit 614 includes a first Darlington transistor IC2-1. In this embodiment, the model of the first voltage comparator IC1-1 is LM393, the model of the first Darlington transistor IC2-1 is ULN2003, and the first Darlington transistor IC2-1 outputs a level signal to the controller of the water dispenser through the first lead wire. The first voltage-dividing resistor R1 is respectively connected to the positive electrode and the negative electrode of the first voltage comparator IC1-1 and is grounded. The second ceramic filter capacitor C2 is connected between the first voltage-dividing resistor R1 and the negative electrode of the first voltage comparator IC1-1. One end of the first ceramic filter capacitor C1 is connected to the connection line between the first voltage-dividing resistor R1 and the positive electrode of the first voltage comparator IC1-1. The other end of the first ceramic filter capacitor C1 is connected to the connection line between the first voltage-dividing resistor R1 and the second ceramic filter capacitor C2. The low liquid level electrode 100 and the conductive fixing ring 500 (hollow bolt) are arranged on the connection line between the first voltage-dividing resistor R1 and the second ceramic filter capacitor C2. When the low liquid level electrode 100 is not connected to the conductive fixing ring 500 (hollow bolt), the first voltage comparator IC1-1 outputs a high level, which is further transmitted to the controller of the water dispenser through the first Darlington tube IC2-1 for processing. When the low liquid level electrode 100 is connected to the conductive fixing ring 500 (hollow bolt), the first voltage comparator IC1-1 outputs a high level, which is further transmitted to the controller of the water dispenser via the first Darlington tube IC2-1 for processing.

[0036] The second voltage-dividing circuit 621 includes an eleventh voltage-dividing resistor R11 and a twelfth voltage-dividing resistor R12 respectively connected to the power supply and arranged in parallel, and a thirteenth voltage-dividing resistor R13 connected in series with the twelfth voltage-dividing resistor R12; the second filtering circuit 622 includes an eleventh ceramic filtering capacitor C11 and a twelfth ceramic filtering capacitor C12; the second voltage comparison circuit 623 includes a second voltage comparator IC1-2; and the second driving circuit 624 includes a second Darlington transistor IC2-2. In this embodiment, the model of the second voltage comparator IC1-2 is LM393, the model of the second Darlington transistor IC2-2 is ULN2003, and the second Darlington transistor IC2-2 outputs a level signal to the controller of the water dispenser through a second lead line. The eleventh voltage-dividing resistor R11 is respectively connected to the positive electrode and the negative electrode of the second voltage comparator IC1-2 and is grounded. The twelfth ceramic filter capacitor C12 is connected between the eleventh voltage-dividing resistor R11 and the negative electrode of the second voltage comparator IC1-2. One end of the eleventh ceramic filter capacitor C11 is connected to the connection line between the eleventh voltage-dividing resistor R11 and the positive electrode of the second voltage comparator IC1-2. The other end of the eleventh ceramic filter capacitor C11 is connected to the connection line between the eleventh voltage-dividing resistor R11 and the twelfth ceramic filter capacitor C12. The high liquid level electrode 200 and the conductive fixing ring 500 (hollow bolt) are arranged on the connection line between the eleventh voltage-dividing resistor R11 and the twelfth ceramic filter capacitor C12. When the high liquid level electrode 200 is not connected to the conductive fixing ring 500 (hollow bolt), the second voltage comparator IC1-2 outputs a high level, which is further transmitted to the controller of the water dispenser through the second Darlington tube IC2-2 for processing. When the high liquid level electrode 200 is connected to the conductive fixing ring 500 (hollow bolt), the second voltage comparator IC1-2 outputs a high level, which is further transmitted to the controller of the water dispenser via the second Darlington tube IC2-2 for processing.

[0037] In addition, the utility model also discloses a water dispenser, which includes the above-mentioned bipolar probe liquid level meter, and also includes a controller, a water pump and a heater electrically connected to the controller, and the controller is a PLC. During the operation of the water dispenser, when the liquid level in the hot tank does not reach the minimum liquid level required for heating of the water dispenser, the controller of the water dispenser controls the water pump to add water to the hot tank, and at this time, the low liquid level control circuit 610 outputs a high-level signal to the outside. When the water level in the hot tank rises to the point where the detection end of the low liquid level electrode 100 contacts the water, the low liquid level electrode 100 forms a loop with the conductive fixing ring 500 and the low liquid level control circuit 610, and the low liquid level control circuit 610 outputs a low-level signal to the outside, and the controller of the water dispenser controls the heater to heat the water in the hot tank, and at this time, the high liquid level control circuit 620 outputs a high-level signal. When the water level continues to rise until the high liquid level electrode 200 contacts the water, the conductive fixing ring 500 is in contact with the high liquid level electrode 200 and the high liquid level control circuit 620, and the high liquid level control circuit 620 outputs a low level signal, and the controller of the water dispenser controls the water pump to stop adding water. When the liquid level is lower than the minimum liquid level, that is, the low liquid level control circuit 610 outputs a high level signal, the water dispenser controller controls the heater to stop heating to avoid dry burning in the hot tank.

[0038] In the implementation of the bipolar probe level gauge for the hot tank of a water dispenser and the water dispenser of the utility model, the high liquid level electrode 200 is processed into a tubular structure and sleeved on the low liquid level electrode 100, the high liquid level electrode 200 is insulated and separated from the low liquid level electrode 100 by the first insulating tube 300, and the high liquid level electrode 200, the conductive fixing ring 500, the hot tank shell and the high liquid level control circuit 620 form a circuit for detecting the high liquid level, and the low liquid level electrode 100, the conductive fixing ring 500, the hot tank shell and the low liquid level control circuit 610 form a circuit for detecting the low liquid level. When the liquid level in the hot tank is at different high and low levels, the high liquid level electrode 200 is insulated and separated from the low liquid level electrode 100 by the first insulating tube 300, and the high liquid level electrode 200, the conductive fixing ring 500, the hot tank shell and the low liquid level control circuit 610 form a circuit for detecting the low liquid level. When the liquid level is level, the low liquid level control circuit 610 and the high liquid level control circuit 620 send different level signals to the water dispenser controller, so that the water dispenser controller controls the device to perform corresponding actions. The low liquid level electrode 100 and the high liquid level electrode 200 are combined to form a probe. In this way, when detecting the liquid level in the hot tank of the water dispenser, only one liquid level meter and a single probe need to be installed to meet the detection of high and low liquid levels of the water dispenser, which reduces the equipment assembly workload and assembly difficulty during the liquid level detection of the water dispenser. The setting of a single probe is conducive to reducing the processing cost of the liquid level meter and the liquid level detection cost of the water dispenser.

[0039] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0040] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A bipolar probe level gauge for a hot tank of a water dispenser, characterized in that: include: A low liquid level electrode, the low liquid level electrode comprising a detection end and a signal transmission end; A high liquid level electrode, which is in a tubular structure, is sleeved on the signal transmission end of the low liquid level electrode, and an insulating area is formed between the high liquid level electrode and the low liquid level electrode; a first insulating tube, wherein the first insulating tube is sleeved on the low liquid level electrode and is located in the insulating area, the inner surface of the first insulating tube abuts against the outer surface of the low liquid level electrode, and the outer surface of the first insulating tube abuts against the inner surface of the high liquid level electrode; A second insulating tube, wherein the second insulating tube is sleeved on the high liquid level electrode, and the inner surface of the second insulating tube abuts against the outer surface of the high liquid level electrode; A conductive fixing ring, the conductive fixing ring is fixedly connected to the outer shell of the hot tank of the water dispenser and is electrically conductive, the conductive fixing ring is sleeved on the second insulating tube and the inner surface of the conductive fixing ring abuts against the outer surface of the second insulating tube; A control circuit board, the control circuit board comprising a low liquid level control circuit electrically connected to the low liquid level electrode, the conductive fixing ring and the water dispenser controller, and a high liquid level control circuit electrically connected to the high liquid level electrode, the conductive fixing ring and the water dispenser controller; The low liquid level control circuit comprises a first voltage divider circuit connected to a power supply, a first filter circuit connected to the first voltage divider circuit, a first voltage comparison circuit connected to the first filter circuit, and a first drive circuit connected to the first voltage comparison circuit, the low liquid level electrode and the conductive fixing ring are both connected to the connection line between the first voltage divider circuit and the first filter circuit, and the output end of the first drive circuit is connected to the water dispenser controller; The high liquid level control circuit includes a second voltage divider circuit connected to a power supply, a second filter circuit connected to the second voltage divider circuit, a second voltage comparison circuit connected to the second filter circuit, and a second drive circuit connected to the second voltage comparison circuit. The high liquid level electrode and the conductive fixed ring are both connected to the connecting line between the second voltage divider circuit and the second filter circuit, and the output end of the second drive circuit is connected to the water dispenser controller.

2. The bipolar probe level gauge according to claim 1, characterized in that: One end of the first insulating tube adjacent to the detection end extends out from the insulating area to form a protective portion.

3. The bipolar probe level gauge according to claim 1, characterized in that: The second insulating tube is sleeved on one end of the high liquid level electrode adjacent to the signal transmission end. The length of the high liquid level electrode is greater than the length of the second insulating tube. An end of the high liquid level electrode adjacent to the detection end forms a high liquid level detection portion on one side of the second insulating tube.

4. The bipolar probe level gauge according to claim 1, characterized in that: The conductive fixing ring is a hollow bolt.

5. The bipolar probe level gauge according to claim 1, characterized in that: The low liquid level electrode and the high liquid level electrode are both made of stainless steel.

6. The bipolar probe level gauge according to claim 1, characterized in that: The first insulating tube and the second insulating tube are both ceramic insulating tubes.

7. The bipolar probe level gauge according to claim 1, characterized in that: The first voltage-dividing circuit includes a first voltage-dividing resistor and a second voltage-dividing resistor respectively connected to a power supply and arranged in parallel, and a third voltage-dividing resistor connected in series with the second voltage-dividing resistor; the first filter circuit includes a first ceramic filter capacitor and a second ceramic filter capacitor; the first voltage comparison circuit includes a first voltage comparator; and the first drive circuit includes a first Darlington transistor.

8. The bipolar probe level gauge according to claim 1, characterized in that: The second voltage-dividing circuit includes an eleventh voltage-dividing resistor and a twelfth voltage-dividing resistor, which are respectively connected to the power supply and arranged in parallel, and a thirteenth voltage-dividing resistor connected in series with the twelfth voltage-dividing resistor; the second filter circuit includes an eleventh ceramic filter capacitor and a twelfth ceramic filter capacitor; the second voltage comparison circuit includes a second voltage comparator; and the second drive circuit includes a second Darlington transistor.

9. A water dispenser, characterized in that: A bipolar probe liquid level gauge comprising any one of claims 1-8.

Images