Conductive liquid detection circuit and mowing robot

Abstract

The present specification provides a conductive liquid detection circuit and a mowing robot, wherein the conductive liquid detection circuit comprises: a liquid sensing unit, a first conduction component, a comparison circuit, a second conduction component, and an output circuit. The liquid sensing unit comprises a liquid containing groove and two electrode pieces. The two electrode pieces are placed in the liquid containing groove. The liquid containing groove is used to contain conductive liquid. When the two electrode pieces are conductive, the liquid sensing unit outputs a voltage to the first conduction component, and the first conduction component is conductive. When the first conduction component is conductive, the comparison circuit outputs a high level to the second conduction component, and the second conduction component is conductive. When the first conduction component is turned off, the comparison circuit outputs a low level to the second conduction component, and the second conduction component is turned off. The output circuit outputs a low level when the second conduction component is conductive, and outputs a high level when the second conduction component is turned off.

Description

TECHNICAL FIELD

[0001] The present specification relates to the technical field of liquid detection, and particularly relates to a conductive liquid detection circuit. The present specification also relates to a mowing robot. BACKGROUND

[0002] With the rapid development of the Internet and artificial intelligence technology, various robots are gradually applied in various aspects of work and life. The robots include a large number of electronic components and devices. When the robots work outdoors, they inevitably encounter rainy weather, which leads to poor working effect, charging failure, and even malfunction of the robots.

[0003] In the prior art, a capacitor can be arranged in a detection circuit of a robot, and whether it is raining can be determined by detecting the change in the capacitance. However, factors such as dew and air humidity can affect the capacitance in the detection circuit, leading to detection errors and failure to determine whether it is raining. The accuracy of determining whether it is raining by detecting the capacitance is low, and it is very easy to misjudge. Therefore, a more accurate method is needed to detect liquid or to perform operations or processing. SUMMARY

[0004] Therefore, the embodiment of the present specification provides a conductive liquid detection circuit. The present specification also relates to a mowing robot to solve the technical defects in the prior art.

[0005] According to a first aspect of the embodiment of the present specification, a conductive liquid detection circuit is provided, which includes a liquid sensing unit, a first conduction component, a comparison circuit, a second conduction component, and an output circuit. The liquid sensing unit, the first conduction component, the comparison circuit, the second conduction component, and the output circuit are connected in sequence.

[0006] The liquid sensing unit includes a liquid containing groove and two electrode sheets. The two electrode sheets are placed in the liquid containing groove. The liquid containing groove is used to contain conductive liquid. When the two electrode sheets are conductive, the liquid sensing unit outputs a voltage to the first conduction component, and the first conduction component is conductive.

[0007] The comparison circuit outputs a high level to the second conduction component when the first conduction component is conductive, and the second conduction component is conductive. When the first conduction component is turned off, a low level is output to the second conduction component, and the second conduction component is turned off. The output circuit outputs a low level when the second conduction component is conductive, and outputs a high level when the second conduction component is turned off.

[0008] According to a second aspect of the embodiments of the present specification, a mowing robot is provided, which comprises the conductive liquid detection circuit of the first aspect, and the liquid sensing unit of the conductive liquid detection circuit is exposed on the mowing robot, and the remaining part of the conductive liquid detection circuit is arranged inside the mowing robot.

[0009] The conductive liquid detection circuit provided by the present specification comprises a liquid sensing unit, a first conduction component, a comparison circuit, a second conduction component, and an output circuit, which are connected in sequence; the liquid sensing unit comprises a liquid containing groove and two electrode sheets, the two electrode sheets are arranged in the liquid containing groove, the liquid containing groove is used for containing conductive liquid, and the liquid sensing unit outputs a voltage to the first conduction component when the two electrode sheets are conductive; the first conduction component is conductive; the comparison circuit outputs a high level to the second conduction component when the first conduction component is conductive, and the second conduction component is conductive, and outputs a low level to the second conduction component when the first conduction component is off, and the second conduction component is off; and the output circuit outputs a low level when the second conduction component is conductive, and outputs a high level when the second conduction component is off.

[0010] In this case, when the liquid containing groove contains sufficient conductive liquid, the two electrode sheets in the liquid sensing unit are conductive, a voltage is generated, the first conduction component is conductive, the comparison circuit outputs a high level to the second conduction component when the first conduction component is conductive, the second conduction component is conductive, and the output circuit outputs a low level; when the liquid containing groove does not contain sufficient conductive liquid, the two electrode sheets in the liquid sensing unit are not conductive, no voltage is generated, the first conduction component is off, the comparison circuit outputs a low level to the second conduction component when the first conduction component is off, the second conduction component is off, and the output circuit outputs a high level. In this way, when the conductive liquid detection circuit outputs a low level, it indicates that the liquid containing groove contains conductive liquid, and when the conductive liquid detection circuit outputs a high level, it indicates that the liquid containing groove does not contain conductive liquid. Whether the level output by the conductive liquid detection circuit is high or low can realize conductive liquid detection, the detection result is less affected by factors such as dew and air humidity, the accuracy of liquid detection is improved, and the liquid detection misjudgment rate is low. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 is a structural framework diagram of a conductive liquid detection circuit provided by an embodiment of the present specification;

[0012] Figure 2is a circuit diagram of a conductive liquid detection circuit provided by an embodiment of the present specification;

[0013] Figure 3 is a structural schematic diagram of a mowing robot provided by an embodiment of the present specification. DETAILED DESCRIPTION

[0014] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present specification. However, the present specification can be practiced without the specific details, other than in the examples described herein. In other instances, well-known methods have not been described in detail in order not to unnecessarily obscure the present specification.

[0015] The terminology used in one or more embodiments of the present specification is for the purpose of describing particular embodiments only and is not intended to be limiting of one or more embodiments of the present specification. As used in one or more embodiments of the present specification and the accompanying claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in one or more embodiments of the present specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0016] It will be understood that, although the terms first, second, etc. can be employed in one or more embodiments of the present specification, these terms are used to distinguish one information from another and are not intended to denote a limitation as to the sequence, amount, or other quantity of the information. For example, a first can be termed a second, and, similarly, a second can be termed a first, without departing from the scope of one or more embodiments of the present specification. As used in this specification, the term "if" can be interpreted to mean "when" or "in response to determining" or "in response to a determination" depending on the context.

[0017] In the present specification, a conductive liquid detection circuit is provided, and the present specification also relates to a mowing robot, which are described in detail one by one in the following embodiments.

[0018] Figure 1 A structural framework diagram of a conductive liquid detection circuit provided by an embodiment of the present specification is shown as follows, Figure 1 As shown, the detection circuit includes a liquid sensing unit 102, a first conduction element 104, a comparison circuit 106, a second conduction element 108, and an output circuit 110, which are connected in sequence.

[0019] The liquid sensing unit 102 includes a liquid accommodating groove and two electrode sheets placed in the liquid accommodating groove, the liquid accommodating groove is used to accommodate conductive liquid, the liquid sensing unit 102 outputs a voltage to the first conduction component 104 when the two electrode sheets are conductive, and the first conduction component 104 is conductive.

[0020] The comparison circuit 106 outputs a high level to the second conduction component 108 when the first conduction component 104 is conductive, and the second conduction component 108 is conductive, and outputs a low level to the second conduction component 108 when the first conduction component 104 is off, and the second conduction component 108 is off; the output circuit 110 outputs a low level when the second conduction component 108 is conductive, and outputs a high level when the second conduction component 108 is off.

[0021] Specifically, the conductive liquid refers to a liquid that can conduct two electrode sheets, such as rainwater, tap water, salt water, etc., that is, water containing impurity ions is a conductive liquid.

[0022] It should be noted that the liquid sensing unit can include a liquid accommodating groove and two electrode sheets, the liquid accommodating groove is used to accommodate conductive liquid, the two electrode sheets can be placed side by side in the liquid accommodating groove, and there is a gap between the two electrode sheets, when the conductive liquid in the liquid accommodating groove meets the conditions, the two electrode sheets will be conductive, the liquid sensing unit will generate a resistance, and output a voltage to the first conduction component, and the first conduction component has a level range requirement, when the output level of the liquid sensing unit meets the requirement, the first conduction component is conductive.

[0023] In actual application, when there is no conductive liquid in the gap between the two electrode sheets, the two electrode sheets are not conductive; if the conductive liquid in the liquid accommodating groove reaches one end of the two electrode sheets, that is, the gap between the two electrode sheets contains conductive liquid, since the conductive liquid has conductivity, the two electrode sheets with a gap are conductive at this time.

[0024] In specific implementation, after the two electrode sheets in the liquid sensing unit are conductive, impedance is generated, current passes through, and the product of current and impedance can obtain output voltage, that is, the liquid sensing unit outputs a voltage to the first conduction component, and the output voltage can conduct the first conduction component; if the two electrode sheets in the liquid sensing unit are not conductive, no impedance is generated, no current passes through, and no voltage is output to the first conduction component, at this time, the first conduction component cannot be conductive and is in an off state. Whether the first conduction component is conductive or not can affect the output result of the comparison circuit, which can affect whether the second conduction component is conductive or off, and whether the second conduction component is conductive or not can affect whether the output circuit finally outputs a high level or a low level.

[0025] For example, if the conductive liquid is rainwater, when it rains, rainwater can accumulate in the liquid accommodating groove of the liquid sensing unit. When the rainwater accumulates to a certain amount, two electrode sheets in the liquid sensing unit are conductive, an impedance is generated, a voltage is output to the first conductive element, the output voltage turns on the first conductive element, at this time, the comparison circuit outputs a high level to the second conductive element, the second conductive element is turned on, and the output circuit outputs a low level.

[0026] In the embodiment of the present specification, when the conductive liquid detection circuit outputs a low level, it indicates that there is conductive liquid in the liquid accommodating groove, and when the conductive liquid detection circuit outputs a high level, it indicates that there is no conductive liquid in the liquid accommodating groove. By determining whether the level output by the conductive liquid detection circuit is high or low, the conductive liquid detection can be realized. The detection result is less affected by factors such as dew and air humidity, the accuracy of liquid detection is improved, and the liquid detection misjudgment rate is low.

[0027] In an optional embodiment of the present embodiment, the first conductive element 104 is a PNP type triode, and the second conductive element 108 is an NPN type triode.

[0028] The liquid sensing unit 102 is connected to the base of the first conductive element 104, the emitter of the first conductive element 104 is connected to the comparison circuit 106, the comparison circuit 106 is connected to the base of the second conductive element 108, and the collector of the second conductive element 108 is connected to the output circuit 110.

[0029] It should be noted that the triode, also known as bipolar transistor or crystal triode, is a semiconductor triode (Bipolar Junction Transistor), also known as bipolar transistor, crystal triode, which is a semiconductor device for controlling current. Its function is to amplify weak signals into larger amplitude signals, and also used as a non-contact switch. The triode is made of two PN junctions on a semiconductor substrate, which divides the whole semiconductor into three parts, the middle part is the base area, and the two side parts are the emitter area and the collector area. There are two arrangements, PNP and NPN. The triode includes three pins, base, emitter and collector. The PNP type triode is a triode with current flowing from the emitter, and the NPN type triode is a triode with current flowing from the emitter.

[0030] In the embodiments of the present application, the first conducting element can be a PNP triode, and the second conducting element can be an NPN triode. The liquid sensing unit is connected to the base of the first conducting element, the emitter of the first conducting element is connected to the comparison circuit, the comparison circuit is connected to the base of the second conducting element, and the collector of the second conducting element is connected to the output circuit, so as to realize the connection of the first conducting element, the comparison circuit, the second conducting element and the output circuit in sequence.

[0031] In an optional embodiment of the present application, the detection circuit further comprises a voltage dividing circuit 112, one end of the voltage dividing circuit 112 is connected to the first high-level input end, and the other end is connected to the comparison circuit;

[0032] The voltage dividing circuit 112 comprises a first feedback resistor and a second feedback resistor, which are used to divide and output the high level input by the first high-level input end to the comparison circuit 106 when the two electrode pieces in the liquid sensing unit 102 are not conducting.

[0033] It should be noted that when the two electrode pieces in the liquid sensing unit are not conducting, there is no voltage input to the comparison circuit, and therefore a voltage dividing circuit can be connected to the comparison circuit. One end of the voltage dividing circuit can be connected to the first high-level input end. The first feedback resistor and the second feedback resistor in the voltage dividing circuit can divide and output the high level input by the first high-level input end to the comparison circuit when the two electrode pieces in the liquid sensing unit are not conducting.

[0034] In actual application, the resistance values of the first feedback resistor and the second feedback resistor can be determined based on the specific level of the first high-level input end. Different resistance values result in different voltage division. For example, the high level provided by the first high-level input end can be 5V, the first feedback resistor can be a 47K resistor, and the second feedback resistor can be a 68K resistor. The first feedback resistor and the second feedback resistor can divide the input 5V high level and then output it to the comparison circuit.

[0035] In the embodiments of the present application, by connecting a voltage dividing circuit to the comparison circuit, the voltage dividing circuit is connected to the first high-level input end, which ensures that the comparison circuit still has a level input when the two electrode pieces in the liquid sensing unit are not conducting, and the level is divided, which avoids the output of a too large level to the comparison circuit when the two electrode pieces in the liquid sensing unit are not conducting.

[0036] In addition, the emitter of the first conducting element can be connected with the first feedback resistor in addition to being connected with the comparison circuit, and the collector of the first conducting element is grounded. When the first conducting element is turned on, the high level of the first high level input end can be grounded through the first feedback resistor to prevent the first conducting element from being burned out by excessive current.

[0037] In an optional embodiment of the present embodiment, the comparison circuit 106 includes an operational amplifier and a feedback circuit. The operational amplifier includes a non-inverting terminal, an inverting terminal and a first output terminal. The first feedback resistor is connected to the non-inverting terminal, the second feedback resistor is connected to the inverting terminal, and the first output terminal is connected to the second conducting element 108.

[0038] The feedback circuit includes a third feedback resistor. One end of the third feedback resistor is connected to the first output terminal, and the other end of the third feedback resistor is connected to the non-inverting terminal. The feedback circuit is configured to feed back the output level of the first output terminal to the non-inverting terminal.

[0039] In the present embodiment, the resistance value of the third feedback resistor can be set based on actual requirements. For example, the third feedback resistor can be a 51K resistor. In addition, when the first output terminal is connected to the second conducting element, the first output terminal can be connected to the base of the second conducting element.

[0040] Specifically, the operational amplifier is a circuit unit with very high amplification. In actual circuits, it is usually combined with a feedback circuit to form a functional module. It is an amplifier with special coupling circuit and feedback. Its output signal can be the result of mathematical operations such as addition, subtraction, differentiation and integration of input signals. The operational amplifier has two input terminals, including a non-inverting terminal (non-inverting input terminal) and an inverting terminal (inverting input terminal), as well as an output terminal.

[0041] It should be noted that if the signal output by the output terminal is introduced into the non-inverting terminal, the signal will continue to be enhanced, that is, positive feedback, until the output signal is comparable to the positive power signal level. At this time, the operational amplifier is generally used as a comparator. At this time, the output voltage of the operational amplifier generally has two extreme values, which are generally the size of the positive and negative power supplies.

[0042] In the present embodiment, the feedback circuit can have one end connected to the first output terminal and the other end connected to the non-inverting terminal, that is, the level output by the first output terminal is fed back to the non-inverting terminal. At this time, the operational amplifier is a kind of comparator, which can compare the levels of the non-inverting terminal and the inverting terminal, and then output the corresponding high and low levels based on the comparison result.

[0043] In actual application, the feedback circuit comprises a third feedback resistor, one end of the third feedback resistor is connected to the first output end, and the other end of the third feedback resistor is connected to the non-inverting terminal, so that the output level of the first output end is fed back to the non-inverting terminal, that is, the non-inverting terminal of the operational amplifier changes based on the level output by the first output end, the output level of the first output end is fed back to the non-inverting terminal, and the operational amplifier can form a steady state.

[0044] In addition, in order to ensure that the level of the inverting terminal of the operational amplifier is higher than the level of the non-inverting terminal when the first conductive element is not conductive, the resistance of the first feedback resistor connected to the inverting terminal can be set to be smaller, and the resistance of the second feedback resistor connected to the non-inverting terminal can be set to be larger. That is, the resistance of the first feedback resistor is smaller than the resistance of the second feedback resistor.

[0045] It should be noted that when the first conductive element is conductive, the first conductive element is equivalent to a resistor, and can take away the level input to the inverting terminal, that is, the level of the inverting terminal of the operational amplifier will decrease, at this time, the level of the inverting terminal is lower than the level of the non-inverting terminal, and the first output end of the operational amplifier outputs a high level; when the first conductive element is not conductive, since the resistance of the second feedback resistor is greater than the resistance of the first feedback resistor, the level of the inverting terminal of the operational amplifier is higher than the level of the non-inverting terminal, at this time, the first output end of the operational amplifier outputs a low level.

[0046] In the embodiments of the present application, whether the first conductive element is conductive or not will affect the high or low of the output level of the operational amplifier in the comparison circuit, and the high or low of the output level of the operational amplifier will further affect whether the second conductive element is conductive or not, thereby affecting the high or low of the final output level, so that whether the level output by the conductive liquid detection circuit is a high level or a low level can realize conductive liquid detection, and improve the accuracy of liquid detection, and the liquid detection misjudgment rate is low.

[0047] In an optional embodiment of the present embodiment, the comparison circuit 106 further comprises a fourth feedback resistor, one end of the fourth feedback resistor is grounded, and the other end of the fourth feedback resistor is connected to the non-inverting terminal, and the fourth feedback resistor is used to provide an initial level to the non-inverting terminal when the first output end does not output a level.

[0048] The resistance of the fourth feedback resistor can be set based on actual requirements, for example, the fourth feedback resistor can be a 100K resistor.

[0049] It should be noted that if the first output end of the operational amplifier does not output a level, one end of the fourth feedback resistor is grounded, and the other end of the fourth feedback resistor is connected to the non-inverting terminal, at this time, the fourth feedback resistor can provide an initial level to the non-inverting terminal, and the initial level is a low level. In this way, it is ensured that the non-inverting terminal can receive a feedback signal when the first output end does not output a level, and the operational amplifier is in a steady state.

[0050] In an alternative embodiment of the present embodiment, the detection circuit further comprises a current-limiting resistor and a pull-down resistor, one end of the current-limiting resistor is connected to the comparison circuit 106, and the other end of the current-limiting resistor is connected to the second conducting element 108.

[0051] One end of the pull-down resistor is grounded, and the other end of the pull-down resistor is connected to the second conducting element 108. The pull-down resistor is used to provide a low level to the second conducting element 108 when the comparison circuit 106 does not output a level.

[0052] It should be noted that the second conducting element generally has a requirement for the level range, and the level range that meets the requirement can be turned on, and cannot be too large, so a current-limiting resistor can also be provided in the detection circuit. The current-limiting resistor is located between the first output end of the operational amplifier and the base of the second conducting element. The current-limiting resistor can reduce the level output by the first output end to avoid the level output by the first output end being too large.

[0053] In actual application, in order to avoid the level output by the first output end being too small, the resistance value of the current-limiting resistor can be set to be relatively small. The resistance value of the current-limiting resistor can be set based on actual requirements. For example, the current-limiting resistor can be a 4.7K resistor.

[0054] In addition, a pull-down resistor can also be provided in the detection circuit. One end of the pull-down resistor can be grounded, and the other end of the pull-down resistor can be connected to the emitter of the second conducting element. In the case that the comparison circuit does not output a level, a low level is provided to the second conducting element through grounding.

[0055] In specific implementation, in order to ensure that the low level grounded can be input to the emitter of the second conducting element, the resistance value of the pull-down resistor is generally also set to be relatively small. For example, the resistance value of the pull-down resistor can be set based on actual requirements. For example, the pull-down resistor can also be a 4.7K resistor.

[0056] In an alternative embodiment of the present embodiment, the output circuit 110 comprises a pull-up resistor and a second output end.

[0057] One end of the pull-up resistor is connected to the second high-level input end, and the other end of the pull-up resistor is connected to the second output end and the second conducting element 108. The second output end and the second conducting element 108 are connected. The pull-up resistor is used to output the high level provided by the second high-level input end when the second conducting element 108 is turned off.

[0058] In actual application, when the pull-up resistor is connected to the second conducting element, the pull-up resistor can be connected to the collector of the second conducting element.

[0059] It should be noted that in the case of the second conducting element being turned off, the low level output by the comparison circuit cannot be transmitted to the second output terminal. In order to avoid the second output terminal having no output, a pull-up resistor can be connected to the second output terminal. The pull-up resistor can be connected to the second high level input terminal. In the case of the second conducting element being turned off, the second high level input terminal can provide a high level to the second output terminal through the pull-up resistor, so that the second output terminal can output a high level.

[0060] In a specific implementation, in order to avoid the level provided by the second high level input terminal being too small, the resistance of the pull-up resistor can also be set to be small. The resistance of the pull-up resistor can be set based on actual requirements. For example, the pull-up resistor can be a 10K resistor, and the second high level input terminal provides a 3.3V high level.

[0061] In addition, in the case of the second conducting element being turned on, the high level output by the comparison circuit can be inverted through the second conducting element, so that the second output terminal outputs a low level. At this time, the high level provided by the second output terminal can be grounded through the pull-up resistor, so that the high level of the second high level input terminal is grounded through the pull-up resistor, to prevent the current from being too large and burning out the second conducting element.

[0062] In an optional implementation of the embodiment, in some cases, unstable voltage and excessively high output level can cause damage to components or affect detection results. Therefore, the detection circuit further includes a voltage stabilizing circuit, and the voltage stabilizing circuit includes a first voltage stabilizing diode and a second voltage stabilizing diode.

[0063] One end of the first voltage stabilizing diode is grounded, and the other end is connected to a path between the liquid sensing unit 102 and the first conducting element 104. The first voltage stabilizing diode is used to conduct current to ground in the case that the output level of the liquid sensing unit 102 is higher than a level threshold.

[0064] One end of the second voltage stabilizing diode is grounded, and the other end is connected to a path between the first conducting element 104 and the comparison circuit 106. The second voltage stabilizing diode is used to conduct current to ground in the case that the output level of the first conducting element 104 is higher than a level threshold.

[0065] In actual application, when the first voltage stabilizing diode is connected to the path between the liquid sensing unit and the first conducting element, the first voltage stabilizing diode can be connected to any position on the path between the liquid sensing unit and the base of the first conducting element. When the second voltage stabilizing diode is connected to the path between the first conducting element and the comparison circuit, the first voltage stabilizing diode can be connected to any position on the path between the emitter of the first conducting element and the comparison circuit.

[0066] It should be noted that the detection circuit can further include a voltage stabilizing circuit, the voltage stabilizing circuit includes a first voltage stabilizing diode and a second voltage stabilizing diode, the first voltage stabilizing diode and the second voltage stabilizing diode are used to prevent overshoot voltage, in the case that the input voltage exceeds the level threshold, the first voltage stabilizing diode and the second voltage stabilizing diode will be turned on to the ground, the current is directly grounded, thereby avoiding that the output level of the liquid sensing unit is too high or the output level of the first conducting component is too high.

[0067] Further, the detection circuit can further include a filtering circuit, the filtering circuit can include at least one capacitor, the capacitor in the filtering circuit is used to filter out useless noise signals in the input signal.

[0068] In addition, in debugging the conductive liquid detection circuit, a reserved resistor can be arranged in the voltage dividing circuit, the reserved resistor is a pull-up resistor when debugging problems occur, an output current is outputted, thereby ensuring that the debugging is successfully performed. Subsequently, when the conductive liquid detection circuit is actually applied, the reserved resistor is removed.

[0069] The conductive liquid detection circuit provided in the specification, when the liquid containing groove contains sufficient conductive liquid, the two electrode sheets in the liquid sensing unit are turned on to generate a voltage, the first conducting component is turned on, when the first conducting component is turned on, the comparison circuit can output a high level to the second conducting component, the second conducting component is turned on, thereby the output circuit outputs a low level; when the liquid containing groove does not contain sufficient conductive liquid, the two electrode sheets in the liquid sensing unit are not turned on, no voltage is generated, at this time, the first conducting component is turned off, when the first conducting component is turned off, the comparison circuit can output a low level to the second conducting component, the second conducting component is turned off, thereby the output circuit outputs a high level. In this way, when the conductive liquid detection circuit outputs a low level, it indicates that the liquid containing groove contains conductive liquid, and when the conductive liquid detection circuit outputs a high level, it indicates that the liquid containing groove does not contain conductive liquid, by whether the level outputted by the conductive liquid detection circuit is high or low, the conductive liquid detection can be realized, the detection result is less affected by factors such as dew and air humidity, the accuracy of liquid detection is improved, and the liquid detection misjudgment rate is low.

[0070] Figure 2 A circuit diagram of a conductive liquid detection circuit according to an embodiment of the specification is shown as follows, Figure 2As shown, the conductive liquid detection circuit includes a liquid sensing unit 102, which is an electrode sheet P5; a first conductive element 104, which is a PNP transistor Q2; a comparison circuit 106 composed of an operational amplifier U1 and a feedback circuit (R21, R22); a second conductive element 108, which is an NPN transistor Q1; an output circuit 110 composed of R10 and an output terminal TP14; and a voltage dividing circuit 112 composed of feedback resistors R11 and R12.

[0071] One end of the electrode sheet P5 is grounded, and the other end is connected to an inductive element L1; one end of the inductive element L1 is connected to the electrode sheet P5, and the other end is connected to a three-way branch, the first branch of which is connected to a capacitor C12 and then grounded, the second branch of which is connected to the base of the PNP transistor Q2, and the third branch of which is connected to a reserved resistor R7 and connected to a first high-level input terminal 5V; the base of the PNP transistor Q2 is also connected to a voltage stabilizing diode D17 and grounded; the emitter of the PNP transistor Q2 is connected to two branches, the first branch of which is connected to the inverting terminal 3 of the operational amplifier U1, and the second branch of which is connected to the feedback resistor R11 and connected to the first high-level input terminal 5V; the connection path between the emitter of the PNP transistor Q2 and the inverting terminal 3 of the operational amplifier U1 is also connected to a capacitor C13 and a voltage stabilizing diode D18, and grounded, and the capacitor C13 and the voltage stabilizing diode D18 are connected in parallel.

[0072] The non-inverting terminal 1 of the operational amplifier U1 is connected to two branches, the first branch of which is connected to the feedback resistor R12 and connected to the first high-level input terminal 5V, and the second branch of which is connected to the feedback resistor R22 and grounded; the operational amplifier U1 also includes a ground pin 2 connected to ground, and a pin 5 connected to the first high-level input terminal 5V, and when connected to the first high-level input terminal 5V, a capacitor C9 is connected and grounded.

[0073] The output terminal 4 of the operational amplifier U1 is connected to two branches, the first branch of which is connected to the feedback resistor R21 and the capacitor C14 (grounded), and the feedback resistor R21 and the capacitor C14 are connected in parallel, and the feedback resistor R21 is connected to the non-inverting terminal 1 of the operational amplifier U1; the second branch is connected to a current limiting resistor R18, and the current limiting resistor R18 is connected to two branches, the first branch of which is connected to the base of the NPN transistor Q1, and the second branch of which is connected to a pull-down resistor R23 and grounded.

[0074] The emitter of the NPN transistor Q1 is grounded, and the collector is connected to two branches, the first branch of which is connected to the output terminal TP14, and the second branch of which is connected to the pull-up resistor R10, and the pull-up resistor R10 is also connected to the output terminal TP14, and the pull-up resistor R10 is also connected to a second high-level input terminal 3.3V.

[0075] Taking rainwater detection as an example, as mentioned above Figure 2 As shown, rainwater is conductive. Accumulated rainwater causes the two electrodes in electrode P5 to conduct, creating an impedance that outputs a voltage to PNP transistor Q2. This voltage turns on PNP transistor Q2, which then acts as a resistor, diverting the input level to the inverting input of operational amplifier U1. This causes the inverting input level of operational amplifier U1 to be lower than the non-inverting input level, resulting in a high-level output from operational amplifier U1. The high-level output from operational amplifier U1 then turns on NPN transistor Q1, inverting the high-level output of operational amplifier U1 to a low level, which is then output through output terminal TP14. In other words, the detection of a low-level output at output terminal TP14 indicates that rainwater has been detected, thus indicating that it is raining.

[0076] When it's not raining, the two electrodes in electrode P5 are not conducting, P5 generates no impedance, and therefore does not output voltage to PNP transistor Q2. At this time, PNP transistor Q2 is off. After PNP transistor Q2 is off, the 5V high level is divided by feedback resistor R11 and output to the inverting terminal of U1, and divided by feedback resistor R12 and output to the non-inverting terminal of U1. Since the resistance of feedback resistor R11 is less than that of feedback resistor R12, the voltage level at the inverting terminal of operational amplifier U1 is higher than that at the non-inverting terminal. Therefore, operational amplifier U1 outputs a low level. The low level output of operational amplifier U1 cannot turn on NPN transistor Q1, meaning NPN transistor Q1 is off. At this time, the 3.3V high level at the second high-level input terminal can be pulled up and input to the output terminal TP14, causing output terminal TP14 to output a high level. In other words, if a high level is detected at output terminal TP14, it means no rain has been detected, and therefore it is determined that it is not raining.

[0077] The conductive liquid detection circuit provided in the specification, when the liquid accommodating groove contains enough rainwater, the two electrode sheets in the liquid sensing unit are conductive, a voltage is generated, the first conduction element is turned on, when the first conduction element is turned on, the comparison circuit can output a high level to the second conduction element, the second conduction element is turned on, so that the output circuit outputs a low level; when the liquid accommodating groove does not contain enough rainwater, the two electrode sheets in the liquid sensing unit are not conductive, no voltage is generated, at this time, the first conduction element is turned off, when the first conduction element is turned off, the comparison circuit can output a low level to the second conduction element, so that the second conduction element is turned off, so that the output circuit outputs a high level. In this way, when the conductive liquid detection circuit outputs a low level, it indicates that rainwater is detected in the liquid accommodating groove, and when the conductive liquid detection circuit outputs a high level, it indicates that there is no rainwater in the liquid accommodating groove. Whether the level output by the conductive liquid detection circuit is high or low, rainwater detection can be realized, the detection result is less affected by factors such as dew and air humidity, the accuracy of rainwater detection is improved, and the misjudgment rate of rain is low.

[0078] Figure 3 A structural schematic diagram of a mowing robot is shown according to an embodiment of the specification, as shown in Figure 3 It is applied to a rainwater detection scene, and the mowing robot 1 is provided with the conductive liquid detection circuit shown in Figures 1-2 The liquid sensing unit 102 in the conductive liquid detection circuit is exposed to the mowing robot 1, the liquid sensing unit 102 includes a liquid accommodating groove 1022 and two electrode sheets 1024, the liquid accommodating groove 1024 is provided with two electrode sheets 1022, when there is rainwater in the liquid accommodating groove 1024, the two electrode sheets 1024 are conductive, the liquid sensing unit 102 is connected with the remaining part 11 of the conductive liquid detection circuit to transmit the voltage generated by the conduction of the two electrode sheets 1024, and the remaining part 11 of the conductive liquid detection circuit can be arranged inside the mowing robot 1.

[0079] It should be noted that the liquid accommodating groove is used to accommodate rainwater, and the two electrode sheets are conductive through the conductivity of the rainwater to generate a voltage, which affects the output level of the conductive liquid detection circuit, so the liquid accommodating groove needs to be exposed to the mowing robot, that is, not blocked by the shell of the mowing robot, so that the liquid accommodating groove can receive rainwater.

[0080] In an optional embodiment of the present embodiment, the mowing robot further comprises a control circuit and a motion unit, the control circuit is connected with the conductive liquid detection circuit and the motion unit, and the control circuit is used to control the motion unit to move according to a set rain-avoiding path when the conductive liquid detection circuit outputs a low level.

[0081] It should be noted that the control circuit can receive the level output by the conductive liquid detection circuit, and if the control circuit determines that the received level is a low level, it indicates that it is currently raining, at which time the control circuit can send a stop working instruction to the movement unit to control the lawn mower robot to stop working, and control the movement unit to move according to the set rain-avoiding path.

[0082] The set rain-avoiding path is a path pre-planned in the control circuit or the movement unit, so that the lawn mower robot can move according to the set rain-avoiding path to achieve automatic rain-avoiding, such as returning to the charging pile from the current position, or moving to the position of the indoor or shelter (such as a rain canopy, eaves, etc.).

[0083] The lawn mower robot provided in the embodiments of the present application is provided with a conductive liquid detection circuit. When the liquid container groove contains sufficient rainwater, the two electrode sheets in the liquid sensing unit are conductive, a voltage is generated, the first conduction element is turned on, when the first conduction element is turned on, the comparison circuit outputs a high level to the second conduction element, the second conduction element is turned on, so that the output circuit outputs a low level; when the liquid container groove does not contain sufficient rainwater, the two electrode sheets in the liquid sensing unit are not conductive, no voltage is generated, at this time the first conduction element is turned off, when the first conduction element is turned off, the comparison circuit outputs a low level to the second conduction element, so that the second conduction element is turned off, so that the output circuit outputs a high level. In this way, when the conductive liquid detection circuit outputs a low level, it indicates that rainwater is detected in the liquid container groove, and when the conductive liquid detection circuit outputs a high level, it indicates that there is no rainwater in the liquid container groove. By outputting a high level or a low level by the conductive liquid detection circuit, rainwater detection can be realized, the detection result is less affected by factors such as dew and air humidity, the accuracy of rainwater detection is improved, and the misjudgment rate of rain is low.

[0084] In addition, the lawn mower robot further includes a control circuit and a movement circuit. The control circuit can accurately determine whether it is raining based on the high or low level output by the conductive liquid detection circuit, so as to automatically control the movement unit to set a rain-avoiding path to move in time, realize automatic rain-avoiding, and avoid problems such as poor working effect of the lawn mower robot, charging failure, and even faults.

[0085] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0086] The preferred embodiments of the present specification disclosed above are only used to help illustrate the present specification. Alternative embodiments do not describe all the details and limit the present application to the specific embodiments described. Obviously, many modifications and changes can be made according to the content of the present specification. The present specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present specification, so that those skilled in the art can well understand and utilize the present specification. The present specification is limited only by the claims and their full scope and equivalents.

Claims

1. A conductive liquid detection circuit, characterized in that, The detection circuit includes: a liquid sensing unit, a first conducting component, a comparator circuit, a second conducting component, and an output circuit, wherein the liquid sensing unit, the first conducting component, the comparator circuit, the second conducting component, and the output circuit are connected in sequence; The liquid sensing unit includes a liquid reservoir and two electrode plates. The two electrode plates are placed side by side in the liquid reservoir, which is used to contain conductive liquid. There is a gap between the two electrode plates. When there is no conductive liquid in the gap between the two electrode plates, the two electrode plates are not conductive. When there is conductive liquid in the gap between the two electrode plates, the two electrode plates are conductive. When the two electrode plates are conductive, the liquid sensing unit outputs a voltage to the first conductive element. The first conductive element conducts when the voltage meets the requirements. When the first conducting element is turned on, the comparison circuit outputs a high level to the second conducting element, and the second conducting element is turned on. When the first conducting element is turned off, the comparison circuit outputs a low level to the second conducting element, and the second conducting element is turned off. The output circuit outputs a low level when the second conducting element is turned on, and outputs a high level when the second conducting element is turned off.

2. The conductive liquid detection circuit according to claim 1, characterized in that, The detection circuit further includes a voltage divider circuit, one end of which is connected to the first high-level input terminal, and the other end of which is connected to the comparison circuit. The voltage divider circuit includes a first feedback resistor and a second feedback resistor. The first feedback resistor and the second feedback resistor are used to divide the high level input from the first high level input terminal and output it to the comparison circuit when the two electrode plates in the liquid sensing unit are not conducting.

3. The conductive liquid detection circuit according to claim 2, characterized in that, The comparator circuit includes an operational amplifier and a feedback circuit. The operational amplifier includes a non-inverting input, an inverting input, and a first output terminal. The first feedback resistor is connected to the non-inverting input, the second feedback resistor is connected to the inverting input, and the first output terminal is connected to the second conducting element. The feedback circuit includes a third feedback resistor, one end of which is connected to the first output terminal and the other end of which is connected to the non-inverting terminal. The feedback circuit is used to feed back the output level of the first output terminal to the non-inverting terminal.

4. The conductive liquid detection circuit according to claim 3, characterized in that, The comparison circuit further includes a fourth feedback resistor, one end of which is grounded and the other end is connected to the non-inverting input. The fourth feedback resistor is used to provide an initial level to the non-inverting input when the first output terminal does not output a level.

5. The conductive liquid detection circuit according to any one of claims 1-4, characterized in that, The detection circuit further includes a current-limiting resistor and a pull-down resistor. One end of the current-limiting resistor is connected to the comparator circuit, and the other end is connected to the second conducting element. One end of the pull-down resistor is grounded, and the other end is connected to the second conducting component. The pull-down resistor is used to provide a low level to the second conducting component when the comparator circuit does not output a level.

6. The conductive liquid detection circuit according to any one of claims 1-4, characterized in that, The output circuit includes a pull-up resistor and a second output terminal; One end of the pull-up resistor is connected to the second high-level input terminal, and the other end is connected to the second output terminal and the second conducting component. The second output terminal and the second conducting component are connected. The pull-up resistor is used to output the high level provided by the second high-level input terminal when the second conducting component is turned off.

7. The conductive liquid detection circuit according to any one of claims 1-4, characterized in that, The detection circuit also includes a voltage regulator circuit, which includes a first Zener diode and a second Zener diode. One end of the first Zener diode is grounded, and the other end is connected to the path between the liquid sensing unit and the first conducting element. The first Zener diode is used to conduct current to ground when the output level of the liquid sensing unit is higher than the level threshold. One end of the second Zener diode is grounded, and the other end is connected to the path between the first conducting element and the comparator circuit. The second Zener diode is used to conduct current to ground when the output level of the first conducting element is higher than the level threshold.

8. The conductive liquid detection circuit according to any one of claims 1-4, characterized in that, The first conducting element is a PNP transistor, and the second conducting element is an NPN transistor; The liquid sensing unit is connected to the base of the first conducting element, the emitter of the first conducting element is connected to the comparator circuit, the comparator circuit is connected to the base of the second conducting element, and the collector of the second conducting element is connected to the output circuit.

9. A lawnmower robot, characterized in that, The lawnmower includes the conductive liquid detection circuit according to any one of claims 1-8, wherein the liquid sensing unit of the conductive liquid detection circuit is exposed in the lawnmower, and the remaining part of the conductive liquid detection circuit is disposed inside the lawnmower.

10. The lawnmower robot according to claim 9, characterized in that, The lawnmower robot also includes a control circuit and a motion unit. The control circuit is connected to the conductive liquid detection circuit and the motion unit. The control circuit is used to control the motion unit to move according to a set rain-avoidance path when the conductive liquid detection circuit outputs a low level.

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