Water sensor structure

Abstract

The utility model discloses a water sensor structure, comprising a wiring unit which is respectively connected with a voltage end and a GND end; the detection unit comprises a first conductive rod and a second conductive rod, and the first conductive rod is connected with voltage through the wiring unit; the current amplification unit is connected with the wiring unit; when no current passes between the first conductive rod and the second conductive rod, the first conduction unit and the second conduction unit are not conducted, and the current amplification unit outputs a low level; when current passes between the first conductive rod and the second conductive rod, the first conduction unit and the second conduction unit are both conducted, and the current amplification unit outputs high level. According to the utility model, a current detection principle is combined with a current amplification circuit structure; compared with a traditional capacitive sensor, the circuit structure is simple, the cost is low, temperature influence is avoided, additional calibration is not needed, the detection efficiency is high, and the precision is high; compared with a traditional photoelectric liquid sensor, the liquid sensor is simple in structure, low in cost, low in water quality requirement and accurate in test result.

Description

Technical Field

[0001] The utility model belongs to the technical field of sensors, and in particular relates to a water sensor structure. Background Art

[0002] Liquid sensors play an important role in the sensor industry. They are key devices used to detect, measure and monitor liquid properties and are widely used in many fields, including industry, medical care, environmental monitoring and food safety. Water detection plays an important role in liquid detection. At present, emerging floor scrubbers are generally equipped with clean water buckets and sewage buckets. The clean water bucket needs to detect whether there is clean water, and the sewage bucket needs to detect whether the sewage is full. There are two main traditional detection methods:

[0003] The first is non-contact capacitive identification. Capacitive liquid sensors use the capacitance between electrodes and liquids to measure the properties of liquids. Usually, the liquid is placed in a container, the electrode is close to the container, and a capacitor is formed between the liquid and the electrode. When the properties or parameters in the liquid change (such as liquid level, density or dielectric constant), the value of the capacitor will also change accordingly, so as to determine the presence or absence of liquid. However, this type of sensor has certain defects: 1. The main circuit is relatively complex and the price is relatively expensive. 2. Capacitive sensors are sensitive to temperature changes because temperature affects the dielectric constant of the liquid, which in turn affects the measurement accuracy of the capacitance value. In order to improve the accuracy, temperature compensation or calibration is required. 3. Capacitive liquid sensors require a certain amount of setup time when detecting liquid changes. Changes in liquid parameters may take a certain amount of time to be reflected in changes in capacitance values; in addition, the response time may also be limited by the characteristics of the sensor itself and circuit delays.

[0004] The second type is the photoelectric liquid sensor, which uses the refraction of the infrared transmitting and receiving tubes. After being immersed in liquid, the refraction changes, and the receiving tube signal changes to judge. The receiver will receive the light signal after passing through the liquid and convert it into an electrical signal for processing and analysis. However, this type of sensor also has certain defects: 1. Photoelectric liquid sensors usually require complex design and manufacturing processes, as well as high-quality optical materials and components, which makes their cost relatively high. 2. Photoelectric liquid sensors use the principle of liquid refraction for detection. After long-term use, scale will remain on the surface of the lens, which will directly affect the test results.

[0005] Therefore, a water sensor structure is designed to solve the above problems.

[0006] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the utility model and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because these solutions are described in the background technology section of the utility model. Utility Model Content

[0007] In order to overcome the above-mentioned deficiencies in the prior art, the purpose of the present utility model is to provide a water sensor structure.

[0008] In order to achieve the above objectives and other related objectives, the technical solution provided by the utility model is: a water sensor structure, comprising:

[0009] A wiring unit, wherein the wiring unit is connected to the voltage terminal and the GND terminal respectively;

[0010] A detection unit, the detection unit comprising a first conductive rod and a second conductive rod, the first conductive rod being connected to the voltage through the wiring unit;

[0011] A current amplifying unit, wherein the current amplifying unit is connected to the wiring unit; the current amplifying unit comprises a first conducting unit, a second conducting unit, a resistor 1 and a resistor 2; the current amplifying unit is connected to the second conductive rod via the first conducting unit; the first conducting unit is connected to the voltage via the resistor 1, and the first conducting unit is connected to the GND terminal; the second conducting unit is connected to the voltage, and the second conducting unit is connected to the GND terminal via the resistor 2; the first conducting unit is connected to the second conducting unit;

[0012] When no current flows between the first conductive rod and the second conductive rod, the first conductive unit and the second conductive unit are both not conductive, and the current amplifying unit outputs a low level;

[0013] When current flows between the first conductive rod and the second conductive rod, the first conductive unit and the second conductive unit are both turned on, and the current amplifying unit outputs a high level.

[0014] In this scheme, the current detection principle is adopted and combined with the current amplification circuit structure to realize the detection of the presence of clean water. It has a simple structure, low cost, is not affected by temperature and does not require additional calibration. It has high detection efficiency, low requirements on water quality, and accurate test results.

[0015] Further, the first conduction unit is an NPN transistor; the emitter of the NPN transistor is connected to the GND terminal, the base of the NPN transistor is connected to the second conductive rod, and the collector of the NPN transistor is connected to the voltage through the resistor 1. In this solution, the first conduction unit uses an NPN transistor, and the three poles of the NPN transistor are connected to corresponding positions in the circuit through different functions, thereby realizing rapid amplification of current.

[0016] Furthermore, the second conduction unit is a PNP transistor; the emitter of the PNP transistor is connected to the voltage, the base of the PNP transistor is connected to the collector of the NPN transistor, and the collector of the PNP transistor is connected to the GND terminal via the resistor 2. In this solution, the second conduction unit uses a PNP transistor, and the three poles of the PNP transistor are connected to corresponding positions in the circuit through different functions, thereby realizing rapid amplification of current.

[0017] Furthermore, a resistor 3 is connected between the first conductive rod and the voltage. In this solution, the resistor 3 can play a role in current limiting; when the conductivity of water is very high (such as: the water is polluted), the resistor 3 can prevent the current from being too large and avoid excessive power consumption of the sensor.

[0018] Further, the wiring unit includes a first wiring port, a second wiring port and a third wiring port, the first wiring port is connected to the voltage, the second wiring port is connected to the GND terminal, and the third wiring port is connected to the collector of the PNP transistor. In this solution, the wiring unit adopts a 3PIN external wiring port to ensure the electrical connection of each path.

[0019] Furthermore, the model of the NPN transistor is MMBT5551. In this solution, the selection of this model of transistor can ensure its amplification factor and achieve a better detection effect.

[0020] Furthermore, the model of the PNP transistor is MMMBT5401. In this solution, the selection of this model of transistor can ensure its amplification factor and achieve a better detection effect.

[0021] Furthermore, the resistance values ​​of the resistor 1, resistor 2, and resistor 3 are all 1kΩ. In this solution, resistor 1 and resistor 2 are both 1kΩ resistors, and are matched with a transistor with an amplification factor of about 200 times, so that the output is fully saturated, ensuring that the output is high level when there is water; resistor 3 is a 1kΩ resistor to ensure its current limiting effect.

[0022] Furthermore, the surface of the first conductive rod and the surface of the second conductive rod are both provided with a gold-plated layer. In this solution, the surface of the first conductive rod and the surface of the second conductive rod are both provided with a gold-plated layer, which can not only improve the conductivity, but also improve the anti-corrosion performance, thereby ensuring the service life of the two conductive rods.

[0023] Furthermore, the first conductive rod and the second conductive rod are respectively connected to two ends of a quick connector. In this solution, the two conductive rods are respectively connected to two ends of a quick connector, which facilitates the stability of the relative positions of the two conductive rods in the water tank and ensures the accuracy of detection.

[0024] Due to the application of the above technical solution, the utility model has the following beneficial effects compared with the prior art:

[0025] The water sensor structure designed by the utility model adopts the current detection principle and combines the current amplification circuit structure to realize the detection of the presence of clean water; compared with the traditional capacitive sensor, the circuit structure is simple, the cost is low, it is not affected by temperature and does not require additional calibration, and the detection efficiency and accuracy are high; compared with the traditional photoelectric liquid sensor, the structure is simple, the cost is low, the water quality requirements are low, and the test results are accurate; and it has wide trial application, long service life, and is suitable for promotion and mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the sensor structure of the utility model;

[0027] In the above figures, 1, wiring unit; 2, detection unit; 3, current amplification unit; 4, first conductive rod; 5, second conductive rod; 6, first conduction unit; 7, second conduction unit; 8, resistor 1; 9, resistor 2; 10, resistor 3. DETAILED DESCRIPTION

[0028] The following is a description of the implementation of the present invention by means of specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0029] It should be noted that in the description of the present utility model, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the utility model product is usually placed when in use, which are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third" and the like are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. Terms such as "horizontal", "vertical", and "overhanging" do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, it can be a mechanical connection, it can be an electrical connection, it can be a direct connection, it can be indirectly connected through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] In the description of the present application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0032] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0033] Embodiment 1: See attached Figure 1 As shown, this embodiment provides a water sensor structure, including:

[0034] Wiring unit 1, wiring unit 1 is connected to the voltage terminal and the GND terminal respectively;

[0035] A detection unit 2, the detection unit 2 comprises a first conductive rod 4 and a second conductive rod 5, the first conductive rod 4 is connected to a voltage via a wiring unit 1;

[0036] The current amplifying unit 3 is connected to the wiring unit 1; the current amplifying unit 3 includes a first conducting unit 6, a second conducting unit 7, a resistor 1 8 and a resistor 2 9; the current amplifying unit 3 is connected to the second conductive rod 5 through the first conducting unit 6; the first conducting unit 6 is connected to the voltage through the resistor 1 8, and the first conducting unit 6 is connected to the GND end; the second conducting unit 7 is connected to the voltage, and the second conducting unit 7 is connected to the GND end through the resistor 2 9; the first conducting unit 6 is connected to the second conducting unit 7;

[0037] When no current flows between the first conductive rod 4 and the second conductive rod 5, the first conductive unit 6 and the second conductive unit 7 are both off, and the current amplifying unit 3 outputs a low level;

[0038] When current flows between the first conductive rod 4 and the second conductive rod 5 , the first conductive unit 6 and the second conductive unit 7 are both turned on, and the current amplifying unit 3 outputs a high level.

[0039] The first conducting unit 6 and the second conducting unit 7 are transistors capable of amplifying current.

[0040] In this embodiment, the voltage is set to 5V, the water flow is ordinary tap water, the conductivity of the water flow is 0.5-5.0*10-2S / m, the resistance R of 1 cm in 1 square is 1 / (σ×A), and the calculated resistance is 5K-50KΩ, then the minimum current of the first conduction unit 6 is about 0.1mA. Select a resistor with a suitable resistance value, so that it reaches saturation and outputs a high level when water flows through; when there is no water, the first conduction unit 6 and the second conduction unit 7 are not conductive and output a low level. The use of dual triode amplification ensures that the output of the current amplification unit 3 is fully saturated, the output is high when there is water, and the output is low when there is no water.

[0041] Resistor 1 8 and resistor 2 9 play a role in voltage conversion. The voltage at one end of resistor 1 8 is 5V, and the other end is grounded.

[0042] In this embodiment, the current detection principle is adopted in combination with the current amplification circuit structure to realize the detection of the presence of clean water. It has a simple structure, low cost, is not affected by temperature and does not require additional calibration, has high detection efficiency, low requirements on water quality, and accurate test results.

[0043] Embodiment 2: See attached Figure 1As shown, this embodiment is a further improvement based on the first embodiment, and its specific method is as follows: the first conduction unit 6 is an NPN transistor; the emitter of the NPN transistor is connected to the GND terminal, the base of the NPN transistor is connected to the second conductive rod 5, and the collector of the NPN transistor is connected to the voltage through a resistor 8.

[0044] In this embodiment, the first conduction unit 6 adopts an NPN transistor, and the three poles of the NPN transistor are respectively connected to corresponding positions in the circuit through different functions, thereby realizing rapid amplification of the current.

[0045] Embodiment 3: See attached Figure 1 As shown, this embodiment is a further improvement based on the second embodiment, and its specific method is: the second conduction unit 7 is a PNP transistor; the emitter of the PNP transistor is connected to the voltage, the base of the PNP transistor is connected to the collector of the NPN transistor, and the collector of the PNP transistor is connected to the GND terminal via the resistor 9.

[0046] In this embodiment, the second conduction unit 7 adopts a PNP transistor, and the three poles of the PNP transistor are respectively connected to corresponding positions in the circuit through different functions, thereby realizing rapid amplification of the current.

[0047] Embodiment 4: See attached Figure 1 As shown, this embodiment is a further improvement on the basis of the third embodiment, and its specific method is as follows: a resistor 3 10 is connected between the first conductive rod 4 and the voltage.

[0048] In this embodiment, resistor three 10 can play a role in current limiting; when the conductivity of water is very high (such as: the water is polluted), resistor three 10 can prevent the current from being too large and avoid excessive power consumption of the sensor.

[0049] Embodiment 5: See attached Figure 1 As shown, this embodiment is a further improvement based on the fourth embodiment, and its specific method is: the wiring unit 1 includes a first wiring port, a second wiring port and a third wiring port, the first wiring port is connected to the voltage, the second wiring port is connected to the GND terminal, and the third wiring port is connected to the collector of the PNP transistor.

[0050] In this embodiment, the connection unit 1 adopts a 3-pin external connection port to ensure the electrical connection of each path.

[0051] Embodiment 6: Not shown in the drawings, this embodiment is a further improvement on the basis of embodiment 5, and its specific method is as follows: the model of the NPN transistor is MMBT5551.

[0052] Among them, the NPN transistor model is MMBT5551, and the amplification factor hFE=100-300.

[0053] In this embodiment, the selection of this type of triode can ensure its amplification factor and achieve a better detection effect.

[0054] Embodiment 7: Not shown in the drawings, this embodiment is a further improvement on the basis of Embodiment 6, and its specific method is as follows: the model of the PNP transistor is MMMBT5401.

[0055] Among them, the PNP transistor model is MMMBT5401, and the amplification factor hFE=100-300.

[0056] In this embodiment, the selection of this type of triode can ensure its amplification factor and achieve a better detection effect.

[0057] Embodiment 8: Not shown in the drawings, this embodiment is a further improvement on the basis of embodiment 7, and its specific method is as follows: the resistance values ​​of resistor 1 8, resistor 2 9, and resistor 3 10 are all 1 kΩ.

[0058] In this embodiment, resistor 1 8 and resistor 2 9 are both 1kΩ resistors, and are combined with a transistor with an amplification factor of about 200 times to make the output fully saturated, ensuring that the output is at a high level when there is water; resistor 3 10 is 1kΩ resistor to ensure its current limiting effect.

[0059] Embodiment 9: Not shown in the drawings, this embodiment is a further improvement on the basis of Embodiment 8, and its specific method is as follows: the surface of the first conductive rod 4 and the surface of the second conductive rod 5 are both provided with a gold-plated layer.

[0060] In this embodiment, a gold-plated layer is provided on the surface of the first conductive rod 4 and the surface of the second conductive rod 5, which can not only improve the conductivity but also improve the anti-corrosion performance, thereby ensuring the service life of the two conductive rods.

[0061] Embodiment 10: Although not shown in the drawings, this embodiment is a further improvement on the basis of Embodiment 9, and its specific method is as follows: the first conductive rod 4 and the second conductive rod 5 are respectively connected to the two ends of a quick connector.

[0062] Wherein, the quick connector is made of non-conductive material. When two conductive rods are connected at both ends of the quick connector, water can still flow into the quick connector, so that the two conductive rods are conductive.

[0063] In this embodiment, two conductive rods are respectively connected to two ends of a quick connector, so as to stabilize the relative positions of the two conductive rods in the water tank and ensure the accuracy of detection.

[0064] The water sensor structure designed by the utility model adopts the current detection principle and combines the current amplification circuit structure to realize the detection of the presence of clean water; compared with the traditional capacitive sensor, the circuit structure is simple, the cost is low, it is not affected by temperature and does not require additional calibration, and the detection efficiency and accuracy are high; compared with the traditional photoelectric liquid sensor, the structure is simple, the cost is low, the water quality requirements are low, and the test results are accurate; and it has wide trial application, long service life, and is suitable for promotion and mass production.

[0065] The above implementation modes are only for illustrating the technical concept and features of the utility model, and their purpose is to allow people familiar with this technology to understand the content of the utility model and implement it. It cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A water sensor structure, characterized in that: include: A wiring unit (1), wherein the wiring unit (1) is connected to a voltage terminal and a GND terminal respectively; A detection unit (2), the detection unit (2) comprising a first conductive rod (4) and a second conductive rod (5), the first conductive rod (4) being connected to the voltage via the wiring unit (1); A current amplifying unit (3), the current amplifying unit (3) being connected to the wiring unit (1); the current amplifying unit (3) comprising a first conducting unit (6), a second conducting unit (7), a resistor 1 (8) and a resistor 2 (9); the current amplifying unit (3) being connected to the second conductive rod (5) via the first conducting unit (6); the first conducting unit (6) being connected to the voltage via the resistor 1 (8), and the first conducting unit (6) being connected to the GND terminal; the second conducting unit (7) being connected to the voltage, and the second conducting unit (7) being connected to the GND terminal via the resistor 2 (9); the first conducting unit (6) being connected to the second conducting unit (7); When no current flows between the first conductive rod (4) and the second conductive rod (5), the first conductive unit (6) and the second conductive unit (7) are both not conductive, and the current amplifying unit (3) outputs a low level; When current flows between the first conductive rod (4) and the second conductive rod (5), the first conductive unit (6) and the second conductive unit (7) are both conductive, and the current amplifying unit (3) outputs a high level.

2. A water sensor structure according to claim 1, characterized in that: The first conducting unit (6) is an NPN transistor; the emitter of the NPN transistor is connected to the GND terminal, the base of the NPN transistor is connected to the second conductive rod (5), and the collector of the NPN transistor is connected to the voltage via the resistor 1 (8).

3. A water sensor structure according to claim 2, characterized in that: The second conducting unit (7) is a PNP transistor; the emitter of the PNP transistor is connected to the voltage, the base of the PNP transistor is connected to the collector of the NPN transistor, and the collector of the PNP transistor is connected to the GND terminal via the resistor 2 (9).

4. A water sensor structure according to claim 3, characterized in that: A resistor three (10) is connected between the first conductive rod (4) and the voltage.

5. A water sensor structure according to claim 4, characterized in that: The wiring unit (1) comprises a first wiring port, a second wiring port and a third wiring port, the first wiring port being connected to the voltage, the second wiring port being connected to the GND terminal, and the third wiring port being connected to the collector of the PNP transistor.

6. A water sensor structure according to claim 5, characterized in that: The model of the NPN transistor is MMBT5551.

7. A water sensor structure according to claim 6, characterized in that: The model of the PNP transistor is MMMBT5401.

8. A water sensor structure according to claim 7, characterized in that: The resistance values ​​of the resistor 1 (8), the resistor 2 (9) and the resistor 3 (10) are all 1 kΩ.

9. A water sensor structure according to claim 8, characterized in that: The surface of the first conductive rod (4) and the surface of the second conductive rod (5) are both provided with a gold-plated layer.

10. A water sensor structure according to claim 9, characterized in that: The first conductive rod (4) and the second conductive rod (5) are respectively connected to two ends of a quick connector.

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