Liquid level detection device
By using open-drain output mode and simple resistor configuration in the liquid level detection equipment, the complexity and cost of existing liquid level detection equipment are solved, and accurate and economical liquid level detection is achieved.
Patent Information
- Application Number
- CN202420552105.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-20
- Publication Date
- 2025-01-14
- Estimated Expiration
- 2034-03-20
AI Technical Summary
The existing liquid level detection equipment has many peripheral devices and high cost and poor probe reliability, resulting in inaccurate detection results. Especially with the increase in use time, factors such as oxidation and ionization will affect the sampling results.
A liquid level detection device is designed, and the detection port of the control chip is used to set in the open drain output mode, and a first resistor and a third resistor are set on the periphery, and formed through the conduction or open circuit state of the first electrode and the second electrode. Effective resistor, read the high and low level signals of the detection port to determine whether the liquid level reaches the specified height, simplify the circuit structure and reduce costs.
The accuracy and convenience of liquid level detection results are achieved, and the complexity and failure rate of equipment are reduced due to the simple circuit and low cost.
Smart Images
Figure CN222353298U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of liquid level detection equipment, and in particular to a liquid level detection device. Background Art
[0002] At present, a main control chip is usually required for liquid level detection. The main control chip can be a microcontroller unit with analog-to-digital conversion function, or a separate analog-to-digital conversion chip. The main control chip determines whether the liquid level has reached the specified height based on the change in the value (such as AD value) converted from the sample. However, the above scheme has the following defects: many peripheral devices, high cost, and as the use time increases, the probe has poor reliability due to factors such as oxidation ionization, which will lead to inaccurate sampling results, thereby causing inaccurate detection results. Utility Model Content
[0003] The present application provides a liquid level detection device, which includes a control chip, a detection circuit module, a first electrode, and a second electrode. The control chip is provided with a detection port. The detection circuit module is connected to the detection port. The detection circuit module includes a first resistor and a third resistor. The first end of the first resistor is connected to a power supply, and the second end is connected to the detection port. The first end of the third resistor is grounded, and the second end is connected to the second end of the first resistor. The first electrode is connected to the second end of the first resistor. The second electrode is grounded and spaced apart from the first electrode. When the first electrode and the second electrode are simultaneously immersed in liquid, the two are conductively connected to form a second resistor, so that the detection port presents a low-level signal. When the circuit between the first electrode and the second electrode is open, the detection port presents a high-level signal.
[0004] Optionally, in some embodiments, the liquid level detection device further includes a protection circuit module, which is connected between the detection port and the second end of the first resistor, and is used for current limiting to protect the control chip and the detection circuit module.
[0005] Optionally, in some embodiments, the protection circuit module includes a current limiting resistor, which is connected in series between the detection port and the second end of the first resistor.
[0006] Optionally, in some embodiments, the protection circuit module further includes a filter capacitor, one end of the filter capacitor is connected to a common point of the detection port and the current limiting resistor, and the other end is grounded.
[0007] Optionally, in some embodiments, the detection circuit module further includes a third resistor, a first end of the third resistor is grounded, and a second end of the third resistor is connected to the second end of the first resistor.
[0008] Optionally, in some embodiments, when the circuit between the first electrode and the second electrode is open, the power-sourcing capability of the third resistor is weaker than the power-sourcing capability of the first resistor.
[0009] Optionally, in some embodiments, when the first electrode and the second electrode are simultaneously immersed in liquid, the power-drawing capability of the equivalent resistor formed by the second resistor and the third resistor in parallel is stronger than the power-drawing capability of the first resistor.
[0010] Optionally, in some embodiments, the first electrode and the second electrode are at different horizontal plane heights, or the first electrode and the second electrode are at the same horizontal plane height.
[0011] Optionally, in some embodiments, the number of detection ports is multiple, the number of detection circuit modules is the same as the number of detection ports and the two are connected one-to-one, the number of first electrodes is the same as the number of detection circuit modules and the two are connected one-to-one, and the multiple first electrodes are arranged at intervals from each other.
[0012] Optionally, in some embodiments, the horizontal heights of the plurality of first electrodes are all higher than the horizontal height of the second electrode; the horizontal heights of the plurality of first electrodes are all the same, or the horizontal height of at least one first electrode is different from the horizontal heights of the remaining first electrodes.
[0013] Optionally, in some embodiments, the liquid level detection device further includes an alarm module, which is connected to the detection port; the alarm module is used to sound an alarm when the detection port presents a high level signal, or to sound an alarm when the detection port presents a low level signal.
[0014] In the liquid level detection device provided by the present application, by setting the detection port of the control chip to an open-drain output mode, and setting a first resistor on the periphery of the control chip to pull electricity upward, when the first electrode and the second electrode are not immersed in liquid at the same time, due to the existence of the first resistor, the electrical signal of the detection port is pulled up to a high level state, and when the first electrode and the second electrode are immersed in liquid at the same time, the conduction between the first electrode and the second electrode is equivalent to forming a second resistor, and the second resistor and the third resistor work together to pull the electrical signal of the detection port down to a low level state. Therefore, by reading the high and low level states of the detection port, it can be determined whether the liquid level has reached the specified height. Not only is the result easy to read, but the detection result is also accurate. In addition, the above-mentioned liquid level detection device can realize liquid level detection by only setting a simple circuit module on the periphery of the control chip, so it also has the advantages of simple circuit structure and low cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the implementation manner will be briefly introduced below. Obviously, the drawings described below are only some implementation manners of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0016] Figure 1It is a structural block diagram of the liquid level detection device in some embodiments of the present application.
[0017] Figure 2 yes Figure 1 Circuit schematic diagram of the liquid level detection device in .
[0018] Description of reference numerals: 100, liquid level detection device; 10, control chip; 101, detection port; 20, detection circuit module; R3, first resistor; 201, first electrode; 202, second electrode; R2, third resistor; 203, power supply; 30, protection circuit module; R1, current limiting resistor; C1, filter capacitor; 40, container; 50, alarm module. DETAILED DESCRIPTION
[0019] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.
[0020] In the description of the present application, it should be understood that the terms "length", "width", "thickness", "up", "down", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or state relationships based on the positions or state relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.
[0021] In addition, some of the above terms may be used to express other meanings in addition to indicating a position or state relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.
[0022] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0023] In addition, unless otherwise expressly specified or limited, the terms "installed", "connected", "connected", "fixed" and the like 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 or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can be internal communication between two elements, or it can be only surface contact. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0024] If certain words are used in the specification and claims to refer to specific components, those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. The specification and claims do not use differences in names as a way to distinguish components, but use differences in components' functions as the criteria for distinction. For example, "including" mentioned throughout the specification and claims is an open term, so it should be interpreted as "including but not limited to"; "substantially" means that those skilled in the art can solve technical problems within a certain error range and basically achieve technical effects.
[0025] See also Figure 1 and Figure 2 The embodiment of the present application provides a liquid level detection device 100, which is used to detect whether the liquid in a container 40 (such as a water tank, a pool, etc.) has reached a specified height. It should be noted that the above-mentioned liquid level detection device 100 can only detect the liquid level of conductive liquids, and is not applicable to all liquids.
[0026] The liquid level detection device 100 includes a control chip 10, a detection circuit module 20, a first electrode 201 and a second electrode 202. As a specific example, the control chip 10 can be a microcontroller unit (MCU). The control chip 10 is provided with a detection port 101, which is an inherent port on the control chip 10 and can be set to an open-drain output mode. The detection circuit module 20 includes a first resistor R3 and a third resistor R2. The first end of the first resistor R3 is connected to the power supply 203, and the second end is connected to the detection port 101. The first resistor R3 is used as a pull-up resistor of the detection port 101, which has the ability to pull electricity upward for the detection port 101. The first end of the third resistor R2 is grounded, and the second end is connected to the second end of the first resistor R3. The third resistor R2 is used as a pull-down resistor of the detection port 101, which has the ability to pull electricity downward for the detection port 101. The first electrode 201 is connected to the first end of the first resistor R3. The second electrode 202 is grounded and spaced apart from the first electrode 201. When the first electrode 201 and the second electrode 202 are immersed in liquid at the same time, conduction between the two is equivalent to forming a second resistor (not shown in the figure), so that the detection port 101 presents a low-level signal; when the circuit between the first electrode 201 and the second electrode 202 is open, that is, the liquid level fails to immerse the first electrode 201 and the second electrode 202 at the same time, the detection port 101 presents a high-level signal.
[0027] Through the above settings, since the detection port 101 of the control chip 10 is set to an open-drain output mode, and the control chip 10 is peripherally provided with a first resistor R3 for pulling electricity upward on the detection port 101 and a third resistor R2 for pulling electricity downward on the detection port 101, and when the first electrode 201 and the second electrode 202 are simultaneously immersed in liquid, the two are connected and can equivalently form a second resistor for pulling electricity downward. Therefore, when the liquid does not simultaneously immerse the first electrode 201 and the second electrode 202, the circuit between the first electrode 201 and the second electrode 202 is open. At this time, under the action of the first resistor R3, the detection port 101 presents a high-level signal; when the liquid simultaneously immerses the first electrode 201 and the second electrode 202, the first electrode 201 and the second electrode 202 are connected. At this time, a second resistor is equivalently formed between the two, and the second resistor and the third resistor R2 jointly pull electricity downward so that the electrical signal of the detection port 101 presents a low-level signal. To sum up, the above-mentioned liquid level detection device 100 can determine whether the liquid level has reached the set position, for example, whether it has reached the specified height, by reading the high and low level signals of the detection port 101. Not only is the result easy to read, but the detection result is accurate and reliable. Moreover, the above-mentioned liquid level detection device 100 only needs to set simple electrical components on the periphery of the control chip 10 to realize the liquid level detection function, and also has the advantages of simple circuit and low cost.
[0028] As a specific example, in actual use, the staff can fix the first electrode 201 at a specified height in the container 40, which is the height at which the liquid in the container 40 needs to be detected, and fix the second electrode 202 at any height in the container 40 that is lower than the first electrode 201. When the detection port 101 is a high-level signal, it indicates that the liquid level in the container 40 is lower than the height of the first electrode 201 (i.e., the specified height); when the detection port 101 is a low-level signal, it indicates that the liquid level in the container 40 is equal to or higher than the height of the first electrode 201 (i.e., the specified height). In some embodiments, the first electrode 201 and the second electrode 202 can be fixed in the container 40 by welding, or can be fixed in the container 40 by snap-fitting.
[0029] See also Figure 2 In some embodiments, the liquid level detection device 100 further includes a protection circuit module 30, which is connected between the detection port 101 and the second end of the first resistor R3, and is used to limit the current to protect the control chip 10 and the detection circuit module 20. The protection circuit module 30 includes a current limiting resistor R1, which is connected in series between the detection port 101 and the second end of the first resistor R3. The current limiting resistor R1 is used to limit the current passing through the detection port 101 to avoid excessive current flowing through the detection port 101 and damaging the control chip 10. In some other embodiments, the protection circuit module 30 further includes a filter capacitor C1, one end of the filter capacitor C1 is connected to the common point of the detection port 101 and the current limiting resistor R1, and the other end is grounded. The filter capacitor C1 is used to reduce the interference of the AC ripple coefficient on the circuit, and can also absorb the current fluctuations generated during the operation of the circuit and the interference connected through the AC power supply 203, so that the working performance of the circuit is more stable.
[0030] Please continue reading Figure 2In some embodiments, the second end of the third resistor R2 is specifically connected to the common point of the first resistor R3, the third resistor R2 and the first electrode 201. Moreover, when the circuit between the first electrode 201 and the second electrode 202 is open, the power-pulling capability of the third resistor R2 is weaker than that of the first resistor R3, and when the first electrode 201 and the second electrode 202 are simultaneously immersed in the solution (to form a second resistor), the power-pulling capability of the equivalent resistor formed by the second resistor and the third resistor R2 in parallel is stronger than that of the first resistor R3. Through the above settings, the third resistor R2 can pull down the electrical signal of the detection port 101. When the circuit between the first electrode 201 and the second electrode 202 is open, the downward pulling ability of the third resistor R2 is weaker than the upward pulling ability of the first resistor R3. Therefore, the detection port 101 is a high-level signal at this time; when the first electrode 201 and the second electrode 202 are simultaneously immersed in the solution to form a second resistor, the third resistor R2 is connected in parallel with the second resistor, and the downward pulling ability of the parallel equivalent resistance of the two is stronger than the upward pulling ability of the first resistor R3, so that the detection port 101 is a low-level signal. Through the above settings, it is possible to determine whether the liquid level has reached the specified height based on the high and low level changes of the electrical signal of the detection port 101.
[0031] In some embodiments, the resistance value of the first resistor R3 can be adjusted as needed. When the types of solutions immersed in the first electrode 201 and the second electrode 202 are different, the resistance value of the second resistor formed when the first electrode 201 and the second electrode 202 are turned on is different, which will cause the downward pulling power of the second resistor to change. In order to ensure that the downward pulling power of the parallel equivalent resistance of the second resistor and the third resistor R2 is greater than the upward pulling power of the first resistor R3, it is necessary to adjust the resistance value of the first resistor R3 (i.e., adjust the upward pulling power of the first resistor R3). The specific resistance value of the first resistor R3 needs to be determined according to the resistance values of the second resistor and the third resistor R2.
[0032] In some embodiments, the resistance value of the third resistor R2 can be adjusted as needed. When the types of solutions immersed in the first electrode 201 and the second electrode 202 are different, the resistance value of the second resistor formed when the first electrode 201 and the second electrode 202 are turned on is different, which will cause the downward pulling power of the second resistor to change. In order to ensure that the downward pulling power of the parallel equivalent resistance of the second resistor and the third resistor R2 is greater than the upward pulling power of the first resistor R3, it is necessary to adjust the resistance value of the third resistor R2 (i.e., adjust the downward pulling power of the third resistor R2), and the specific resistance value of the third resistor R2 needs to be determined according to the resistance values of the second resistor and the first resistor R3.
[0033] In some embodiments, the resistance values of the first resistor R3 and the third resistor R2 can be adjusted as needed, and the staff can adjust the resistance values of the two at the same time to ensure that after the first electrode 201 and the second electrode 202 are connected to form the second resistor, the downward pulling ability of the parallel equivalent resistance of the second resistor and the third resistor R2 is greater than the upward pulling ability of the first resistor R3. It is also necessary to ensure that when the first electrode 201 and the second electrode 202 are open, the upward pulling ability of the first resistor R3 is stronger than the downward pulling ability of the third resistor R2, so that the high and low level states of the detection port 101 can correspond to whether the reaction liquid level reaches the specified height.
[0034] As a specific example, the first electrode 201 and the second electrode 202 are arranged at different horizontal plane heights, for example, Figure 2 As shown, the horizontal plane height of the first electrode 201 is higher than the horizontal plane height of the second electrode 202. When the first electrode 201 and the second electrode 202 are immersed in liquid at the same time, the two are connected to form a second resistor, so that the detection port 101 is a low-level signal; when the circuit between the first electrode 201 and the second electrode 202 is open, that is, the liquid level does not reach the horizontal plane height of the first electrode 201, the detection port 101 is a high-level signal. In a specific usage scenario, the high and low level signals of the detection port 101 can be used to determine whether the liquid level of the solution has reached the liquid level height (the horizontal plane height of the first electrode 201) that needs to be detected. When the controller obtains the low level / high level signal of the detection port 101, it can control the relevant equipment to send a reminder to the staff so that the staff can adjust the water level, or the controller automatically controls the water level adjustment equipment to adjust the water level.
[0035] In some other embodiments, the horizontal plane height of the second electrode 202 can also be set higher than the horizontal plane height of the first electrode 201. In this case, when the first electrode 201 and the second electrode 202 are immersed in liquid at the same time, the two are connected to form a second resistor, so that the detection port 101 presents a low-level signal; when the circuit between the first electrode 201 and the second electrode 202 is open, that is, the liquid level does not reach the horizontal plane height of the second electrode 202, the detection port 101 presents a high-level signal. In a specific usage scenario, the high and low level signals of the detection port 101 can be used to determine whether the liquid level of the solution has reached the liquid level height (the horizontal plane height of the second electrode 202) to be detected. When the controller obtains the low level / high level signal of the detection port 101, it can control the relevant equipment to send a reminder to the staff so that the staff can adjust the water level, or the controller automatically controls the water level adjustment equipment to adjust the water level.
[0036] In some other embodiments, the first electrode 201 and the second electrode 202 can also be set at the same horizontal plane height. At this time, when the liquid level reaches the horizontal plane height where the first electrode 201 and the second electrode 202 are located, the liquid will simultaneously immerse the first electrode 201 and the second electrode 202 so that the two are connected, so that the detection port 101 presents a low level signal; on the contrary, when the liquid level does not reach the horizontal plane height where the first electrode 201 and the second electrode 202 are located, the first electrode 201 and the second electrode 202 are open, so that the detection port 101 presents a high level signal. In a specific use scenario, the high and low level signals of the detection port 101 can be used to determine whether the liquid level of the solution reaches the liquid level height to be detected (the horizontal plane height where the first electrode 201 and the second electrode 202 are located together). When the controller obtains the low level / high level signal of the detection port 101, it can control the relevant equipment to send a reminder to the staff so that the staff can adjust the water level, or the controller automatically controls the water level adjustment equipment to adjust the water level.
[0037] In some embodiments, the number of detection ports 101 may be multiple, for example, it may be any integer number such as two, three, four, etc., the number of detection circuit modules 20 is the same as the number of detection ports 101 and the two are connected in a one-to-one correspondence, the number of first electrodes 201 is the same as the number of detection circuit modules 20 and the two are connected in a one-to-one correspondence, and the multiple first electrodes 201 are arranged at intervals from each other. Through the above arrangement, when the solution simultaneously immerses the first electrode 201 and the second electrode 202, the detection port 101 connected to the immersed first electrode 201 will present a low-level signal, and by arranging the multiple first electrodes 201 at different horizontal plane heights, the detection of multiple specified heights of the solution can be achieved. In some other embodiments, the number of second electrodes 202 may also be multiple, and the number of second electrodes 202 is the same as the number of first electrodes 201.
[0038] In some embodiments, the horizontal plane heights of the plurality of first electrodes 201 are all higher than the horizontal plane heights of the second electrode 202, and the horizontal plane heights of the plurality of first electrodes 201 are all the same. In the above case, the plurality of first electrodes 201 at the same horizontal plane heights can be respectively arranged in a plurality of different containers 40 that are interconnected, and the second electrode 202 can be arranged in one of the containers 40. Through the above arrangement, through the high and low level signals of the detection port 101 connected to each first electrode 201, it can be determined whether the liquid level of the solution in the container 40 where the first electrode 201 is located has reached the specified height. If the detection port 101 is a low level signal, it indicates that the liquid level of the solution in the corresponding container 40 has reached the specified height. If the detection port 101 is a high level signal, it indicates that the liquid level of the solution in the corresponding container 40 has not reached the specified height.
[0039] In some other embodiments, the horizontal plane heights of the plurality of first electrodes 201 are all higher than the horizontal plane heights of the second electrode 202, and the horizontal plane height of at least one first electrode 201 is different from the horizontal plane heights of the remaining first electrodes 201. As a specific example, in some embodiments, the horizontal plane heights of the first electrodes 201 are all different. In this case, the plurality of first electrodes 201 can be arranged in the same container 40, or in a plurality of different containers 40 that are interconnected. When the plurality of first electrodes 201 are arranged in the same container 40, it is possible to determine whether the liquid level of the solution in the container 40 has reached the height of the corresponding first electrode 201 according to the high and low level signals of different detection ports 101, so as to realize multi-level detection of the liquid level of the container. When the plurality of first electrodes 201 are arranged in a plurality of different containers 40 that are interconnected, it is possible to determine whether the liquid level of the solution in the corresponding container 40 has reached the height of the corresponding first electrode 201 according to the high and low level signals of different detection ports 101, so as to realize detection of the liquid level height in the pairs of containers 40 that are interconnected. The liquid level detection device 100 should follow the following principle during specific use: the horizontal plane heights of the plurality of first electrodes 201 located in the same container 40 should be different.
[0040] Please refer again Figure 2 In some embodiments, the liquid level detection device 100 further includes an alarm module 50, which is connected to the detection port 101; the alarm module 50 can sound an alarm when the detection port 101 presents a high level signal, and the alarm module 50 is used to remind the staff that the liquid level of the detected solution is lower than the specified height. In some other embodiments, the alarm module 50 can sound an alarm when the detection port 101 presents a low level signal, and the alarm module 50 is used to remind the staff that the liquid level of the detected solution reaches the specified height. As a specific example, the alarm module 50 can be a buzzer or an indicator light or a combination of a buzzer and an indicator light.
[0041] In summary, the present embodiment provides a liquid level detection device 100, which realizes liquid level detection by setting the detection port 101 of the control chip 10 to an open-drain output mode, and connecting the detection port 101 to the detection circuit module 20, and realizing liquid level detection by the high and low level changes of the detection port 101. Among them, the detection circuit module 20 includes a first resistor R3 and a third resistor R2, the first end of the first resistor R3 is connected to the power supply 203, and the second end is connected to the detection port 101, and the first resistor R3 is used as a pull-up resistor of the detection port 101, which has the ability to pull electricity upward to the detection port 101. The first end of the third resistor R2 is grounded, and the second end is connected to the second end of the first resistor R3. The third resistor R2 is used as a pull-down resistor of the detection port 101, which has the ability to pull electricity downward to the detection port 101. The first electrode 201 is connected to the first end of the first resistor R3. The second electrode 202 is grounded and spaced apart from the first electrode 201. When the first electrode 201 and the second electrode 202 are simultaneously immersed in liquid, the two are connected to form a second resistor. Since the downward pulling power capability of the equivalent resistor formed by the second resistor and the third resistor R2 in parallel is weaker than the upward pulling power capability of the first resistor R3, the detection port 101 presents a low level signal; when the circuit between the first electrode 201 and the second electrode 202 is open, that is, the liquid level fails to reach the horizontal plane height of the first electrode 201 and the second electrode 202 at the same time, since the upward pulling power capability of the first resistor R3 is stronger than the downward pulling power capability of the third resistor R2, the detection port 101 presents a high level signal. Therefore, the above-mentioned liquid level detection device 100 can know whether the horizontal height of the liquid level reaches the specified height by reading the high and low levels of the detection port 101. Not only is the result easy to read, but the detection result is accurate and reliable. In addition, the above-mentioned liquid level detection device 100 only needs to set simple electrical components on the periphery of the control chip 10 to realize the liquid level detection function, and also has the advantages of simple circuit and low cost.
[0042] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.
[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application is described in detail with reference to the above embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents. However, these modifications or replacements do not drive the essence of the corresponding technical solutions out of the spirit and scope of the technical solutions of the embodiments of the present application.
Claims
1. A liquid level detection device, characterized in that: The liquid level detection device comprises: A control chip, wherein the control chip is provided with a detection port; A detection circuit module is connected to the detection port; the detection circuit module includes a first resistor and a third resistor; the first end of the first resistor is connected to a power supply, and the second end is connected to the detection port; the first end of the third resistor is grounded, and the second end is connected to the second end of the first resistor; a first electrode connected to a second end of the first resistor; and a second electrode, the second electrode being grounded and spaced apart from the first electrode; When the first electrode and the second electrode are immersed in liquid at the same time, conduction between the two is equivalent to forming a second resistor, so that the detection port presents a low-level signal; when the first electrode and the second electrode are open, the detection port presents a high-level signal.
2. The liquid level detection device according to claim 1, characterized in that: The liquid level detection device further includes a protection circuit module, which is connected between the detection port and the second end of the first resistor, and is used for current limiting to protect the control chip and the detection circuit module.
3. The liquid level detection device according to claim 2, characterized in that: The protection circuit module includes a current limiting resistor, which is connected in series between the detection port and the second end of the first resistor.
4. The liquid level detection device according to claim 3, characterized in that: The protection circuit module further comprises a filter capacitor, one end of which is connected to a common point of the detection port and the current limiting resistor, and the other end of which is grounded.
5. The liquid level detection device according to claim 1, characterized in that: When the circuit between the first electrode and the second electrode is open, the current-sourcing capability of the third resistor is weaker than the current-sourcing capability of the first resistor.
6. The liquid level detection device according to claim 1, characterized in that: When the first electrode and the second electrode are immersed in liquid at the same time, the equivalent resistor formed by the second resistor and the third resistor in parallel has a stronger current-drawing capability than the first resistor.
7. The liquid level detection device according to claim 1, characterized in that: The first electrode and the second electrode are at different horizontal plane heights, or the first electrode and the second electrode are at the same horizontal plane height.
8. The liquid level detection device according to any one of claims 1 to 6, characterized in that: The number of the detection ports is multiple, the number of the detection circuit modules is the same as the number of the detection ports and the two are connected one-to-one, the number of the first electrodes is the same as the number of the detection circuit modules and the two are connected one-to-one, and the multiple first electrodes are arranged at intervals from each other.
9. The liquid level detection device according to claim 8, characterized in that: The horizontal plane heights of the plurality of first electrodes are all higher than the horizontal plane height of the second electrode; The horizontal plane heights of the plurality of first electrodes are all the same, or the horizontal plane height of at least one of the first electrodes is different from the horizontal plane heights of the remaining first electrodes.
10. The liquid level detection device according to any one of claims 1 to 7, characterized in that: The liquid level detection device further comprises an alarm module, which is connected to the detection port; the alarm module is used to issue an alarm when the detection port presents a high level signal, or to issue an alarm when the detection port presents a low level signal.