Contact type liquid level detection cleaning equipment

Abstract

The utility model provides contact type liquid level detection cleaning equipment which comprises a machine body, and a main control module and a liquid level detection module are integrated in the machine body; the liquid level detection module comprises a capacitive liquid level detection chip and a capacitive liquid level detection circuit; the grip is detachably arranged on the machine body through the connecting rod, and the connecting rod is of a telescopic structure; the sewage tank is detachably mounted at the front part of the machine main body, and the sewage tank comprises a solid-liquid separation cavity and a sewage accommodating cavity which are separated from each other up and down; the first sensor is arranged at the bottom of the solid-liquid separation cavity, and the first sensor extends into the sewage accommodating cavity; the clear water tank is detachably mounted at the rear part of the machine main body; the second sensor is arranged at the bottom of the clear water tank; the first sensor and the second sensor are used for detecting liquid level information in the clear water tank and the sewage accommodating cavity respectively and transmitting the detected liquid level information to the capacitive liquid level detection chip respectively.

Description

Technical Field

[0001] The present application relates to the technical field of cleaning equipment, and in particular to a cleaning equipment for contact-type liquid level detection. Background Art

[0002] In the related technology, most of the existing cleaning equipment detects liquid level information through two conductors. There are many types of liquid level sensors currently used in the market, including float type, photoelectric type, capacitive type, ultrasonic type, etc., each with its own advantages and disadvantages. Any object has capacitance, and the capacitance is related to the dielectric constant and volume size. The liquid level sensor determines the height of the liquid or the presence of liquid by detecting the change in the capacitance of the object. After the liquid level sensor is placed close to the container wall, a capacitor similar to parallel plates is formed between it and the liquid. The capacitance value of this capacitor is affected by the interaction area between the liquid and the sensor and the dielectric constant of the container wall. Utility Model Content

[0003] In order to solve the above technical problems, the present application proposes a cleaning device for contact liquid level detection, comprising:

[0004] The fuselage body has a main control module and a liquid level detection module integrated therein; the liquid level detection module includes: a capacitive liquid level detection chip and a capacitive liquid level detection circuit;

[0005] A grip and a connecting rod, wherein the grip is detachably arranged on the fuselage body through the connecting rod, and the connecting rod has a retractable structure;

[0006] A sewage tank, which is detachably mounted on the front of the fuselage body and includes a solid-liquid separation chamber and a sewage receiving chamber which are separated into upper and lower parts;

[0007] A first sensor is arranged at the bottom of the solid-liquid separation chamber, and the first sensor extends into the sewage receiving chamber;

[0008] A fresh water tank, which is detachably mounted at the rear of the fuselage;

[0009] A second sensor is disposed at the bottom of the clean water tank;

[0010] The first sensor and the second sensor detect the liquid level information in the clean water tank and the sewage containing chamber respectively, and the first sensor and the second sensor transmit the detected liquid level information to the capacitive liquid level detection chip respectively.

[0011] The present application is further configured such that the first sensor and the second sensor include: a conductive metal sheet, a spring, a conductive tape, a conductive cotton or a thermistor.

[0012] Through the above technical solution, the capacitive liquid level detection module monitors the liquid level in the clean water tank and the sewage tank to avoid overflow. Among them, the capacitive liquid level detection chip is mainly used to collect the capacitance of the liquid level detection sensor and the capacitance of the comparison circuit channel, and obtain high and low level signal outputs through internal logic processing.

[0013] The present application is further configured such that the liquid level detection circuit includes: a capacitive liquid level detection chip, a comparison circuit, a charge collector, a discharge circuit, an open-drain output circuit, and a decoupling circuit; the first sensor and the second sensor are respectively connected to the capacitive liquid level detection chip, and the capacitive liquid level detection chip is respectively connected to the open-drain output circuit, the comparison circuit, the discharge circuit, the charge collector, and the decoupling circuit.

[0014] The present application is further configured such that the first sensor and the second sensor are respectively connected to the capacitive liquid level detection chip via R3, and the resistor R3 is used to improve the conduction anti-interference and the radiation anti-interference.

[0015] The present application is further configured such that the charge collector includes a CMOD capacitor for collecting changes in all parasitic capacitances attached to the capacitive sensor; and the discharge circuit includes a CDC discharge capacitor for discharging the CMOD capacitor.

[0016] The present application is further configured as a capacitance comparison circuit, comprising a capacitor C1, one end of the capacitor C1 being grounded, and the other end being connected to a capacitive liquid level detection chip via R1.

[0017] The present application is further configured such that the open-drain output circuit is output to an external host device through R4, and needs to be connected to the power supply terminal of the capacitive liquid level detection chip through a pull-up resistor R2.

[0018] The present application is further configured such that the decoupling circuit includes a capacitor C2, and two ends of the capacitor C2 are respectively connected to a power supply end and a ground end of the capacitive liquid level detection chip.

[0019] The present application is further configured such that the charge collector is used to collect the change in all parasitic capacitances attached to the sensor, and compares it with the internal comparator of the capacitive liquid level detection chip. When the change exceeds the reference voltage set inside the capacitive liquid level detection chip, the CDC discharge capacitor selection switch is turned on inside the capacitive liquid level detection chip to discharge the CMOD capacitor.

[0020] The present application is further configured such that the capacitive liquid level detection chip converts analog quantities of all additional parasitic capacitance values ​​on the first sensor and second sensor channels and all additional parasitic capacitance values ​​on the capacitance comparison circuit channel into digital quantities of the number of switching times of the CDC discharge capacitance selection switch through a charge and discharge mode.

[0021] The beneficial effect of the present application is that compared with the existing resistive liquid level detection module, the advantage of using a capacitive liquid level detection module is that the circuit layout is simple, the sensitivity is high, and reasonable adjustment of the water point can effectively avoid the influence of water droplets hanging on the wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are included to provide a further understanding of the embodiments and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate the embodiments and are used together with the description to explain the principles of the present application. It will be easy to recognize other embodiments and many expected advantages of the embodiments because they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale with each other. The same reference numerals refer to corresponding similar parts.

[0023] Figure 1 is a structural schematic diagram of a cleaning device for contact-type liquid level detection according to an embodiment of the present application;

[0024] Figure 2 is a schematic structural diagram of a sewage tank of a cleaning device for contact-type liquid level detection according to an embodiment of the present application;

[0025] Figure 3 is a schematic structural diagram of a clean water tank of a cleaning device with contact-type liquid level detection according to an embodiment of the present application;

[0026] Figure 4 is a circuit diagram of a capacitive liquid level detection circuit of a cleaning device for contact liquid level detection according to an embodiment of the present application;

[0027] Figure 5 It is a circuit principle block diagram of a cleaning device for contact liquid level detection according to an embodiment of the present application.

[0028] The meaning of the numbers in the figure:

[0029] 1. Body; 2. Handle; 3. Connecting rod; 4. Sewage tank; 4a. Sewage holding chamber; 4b. Solid-liquid separation chamber; 5. Clean water tank; 6a. First sensor; 6b. Second sensor; 7. Capacitive liquid level detection chip; 8a. Decoupling circuit; 8b. Filter circuit; 8c. Open-drain output circuit; 8d. Charge collector; 8e. Discharge circuit; 8f. Comparison circuit. DETAILED DESCRIPTION

[0030] In the following detailed description, reference is made to the accompanying drawings, which form a part of the detailed description and are shown by illustrative specific embodiments in which the present application can be practiced. To this end, directional terms, such as "top", "bottom", "left", "right", "up", "down", etc., are used with reference to the orientation of the figures described. Because the components of the embodiments can be positioned in several different orientations, directional terms are used for the purpose of illustration and are by no means limiting. It should be understood that other embodiments may be utilized or logical changes may be made without departing from the scope of the present application. Therefore, the following detailed description should not be adopted in a limiting sense, and the scope of the present application is defined by the appended claims.

[0031] Figure 1 is a structural schematic diagram of a cleaning device for contact-type liquid level detection according to an embodiment of the present application, Figure 2 is a structural schematic diagram of a sewage tank of a cleaning device for contact-type liquid level detection according to an embodiment of the present application, Figure 3 is a schematic structural diagram of a clean water tank of a cleaning device for contact-type liquid level detection according to an embodiment of the present application, such as Figures 1 to 3 As shown, a cleaning device for contact liquid level detection includes:

[0032] The fuselage body 1 has a main control module and a liquid level detection module integrated therein; the liquid level detection module comprises: a capacitive liquid level detection chip 7 and a capacitive liquid level detection circuit;

[0033] A handle 2 and a connecting rod 3, wherein the handle 2 is detachably arranged on the fuselage body 1 through the connecting rod 3, and the connecting rod 3 has a retractable structure;

[0034] A sewage tank 4, which is detachably mounted on the front of the main body 1, and includes a solid-liquid separation chamber 4b and a sewage receiving chamber 4a which are separated into upper and lower parts;

[0035] The first sensor 6a is disposed at the bottom of the solid-liquid separation chamber 4b, and the first sensor 6a extends into the sewage receiving chamber 4a;

[0036] A clean water tank 5, which is detachably mounted at the rear of the fuselage body 1;

[0037] The second sensor 6b is arranged at the bottom of the clean water tank 5;

[0038] The first sensor 6a and the second sensor 6b detect the liquid level information in the clean water tank 5 and the sewage containing chamber 4a respectively, and the first sensor 6a and the second sensor 6b transmit the detected liquid level information to the capacitive liquid level detection chip 7 respectively.

[0039] The first sensor 6a and the second sensor 6b include: conductive metal sheets, springs, conductive tapes, conductive cotton or thermistors. In addition, the number of the first sensor 6a and the second sensor 6b is not limited.

[0040] Figure 5 is a circuit principle block diagram of a cleaning device for contact-type liquid level detection according to an embodiment of the present application, such as Figure 5 As shown, the liquid level detection circuit includes: a capacitive liquid level detection chip, a capacitance comparison circuit 8f, a charge collector 8d, a discharge circuit 8e, an open-drain output circuit 8c, and a decoupling circuit 8a; the first sensor 6a and the second sensor 6b are respectively connected to the capacitive liquid level detection chip 7, and the capacitive liquid level detection chip 7 is respectively connected to the open-drain output circuit 8c, the capacitance comparison circuit 8f, the discharge circuit 8e, the charge collector 8d, and the decoupling circuit 8a.

[0041] Further integration Figure 4 , the first sensor 6a and the second sensor 6b are connected to the capacitive liquid level detection chip 7 through R3 respectively, and the resistor R3 is used to improve the conduction anti-interference and radiation anti-interference; the charge collector 8d includes a CMOD capacitor, which is used to collect the change of all the additional parasitic capacitances of the capacitive sensor; the discharge circuit 8e includes a CDC discharge capacitor, which is used to discharge the CMOD capacitor; the open-drain output circuit 8c is output to the external host device through R4, and needs to be connected to the power supply end of the capacitive liquid level detection chip 7 through the pull-up resistor R2; the decoupling circuit 8a includes a capacitor C2, and the two ends of the capacitor C2 are respectively connected to the power supply end of the capacitive liquid level detection chip 7 and Ground terminal; the charge collector 8d is used to collect the change of all the parasitic capacitances attached to the sensor, and compare it with the internal comparator of the capacitive liquid level detection chip 7. When it exceeds the reference voltage set inside the capacitive liquid level detection chip 7, the CDC discharge capacitor gating switch is turned on inside the capacitive liquid level detection chip 7 to discharge the CMOD capacitor; the capacitive liquid level detection chip 7 converts the analog quantities of all the parasitic capacitance values ​​attached to the channels of the first sensor 6a and the second sensor 6b and all the parasitic capacitance values ​​attached to the channels of the capacitance comparison circuit 8f into digital quantities of the number of switching times of the CDC discharge capacitor gating switch through the charge and discharge mode.

[0042] In order to better illustrate this application, take the SC01 chip as an example, combined with Figure 4 , Figure 5As shown, the sensor is connected to CIN2 of the capacitive liquid level detection chip 7 through a resistor R3. The sensor includes a flat-top spring, a spiral spring, conductive cotton, conductive cloth, PCB copper foil, a probe or a micro copper tube copper column and other conductive dielectric materials. The general sensor design requires a certain sensing area, and the area is preferably rectangular. The sensor should be designed to have a sensing area as large as possible, and the sensor parasitic capacitance is as small as possible, controlled within 10PF, and the sensing area is designed as much as possible between 4*4mm-30*30mm to ensure a large sensing area, so as to ensure high sensitivity and high accuracy. The sensor collects the change in capacitance caused by the change in liquid level, and the change is introduced by a resistor R3 to make a logical judgment inside the liquid level chip. The R3 resistor is mainly used to improve the conduction anti-interference and radiation anti-interference, etc., which is helpful for the product EMC performance. The selection range is between 0-10KΩ, and the general recommended value is 3KΩ. In other optional implementations, other types of sensors can also be used.

[0043] More specifically, the decoupling circuit 8a and the filtering circuit 8b need to strengthen the EMC and other interference issues in different power supply environments. The decoupling circuit 8a includes a capacitor C2, and the generally recommended value is 100nF; the filtering circuit 8b includes a large capacitor C3 connected in series between the power supply and the ground, including a front-end power supply connection inductor L1 / magnetic beads or a ground line connected in series with an inductor / magnetic bead. The selection of components of these circuits is determined according to the characteristics of the power supply;

[0044] The open-drain output circuit 8c requires an external pull-up resistor R2 for the open-drain output, and the series resistor R4 is mainly used to protect the capacitive liquid level detection chip 7 to prevent the external voltage from being applied and the large current from being reversed to damage the capacitive liquid level detection chip 7. When it is detected that there is liquid or the liquid height reaches the position to be measured, the output is a low level. When it is detected that there is no liquid or the liquid level is not as high as the position to be measured, the output is a low level. In this application, the output level can be changed according to the needs, and circuits such as inverters can be added to change the output level signal;

[0045] The charge collector 8d includes a CMOD capacitor, the CMOD capacitor value is generally set at 1nF to 10nF, and the recommended value is 4.7nF. It is used to collect the change of all parasitic capacitances attached to the capacitive sensor;

[0046] The discharge circuit 8e includes a CDC capacitor, which is used to discharge the CMOD charge collector 8d. The capacitor is mainly used to adjust the sensitivity of the sensor to liquid. The smaller the CDC capacitor, the more sensitive it is to liquid, and vice versa. The adjustment range of the CDC capacitor is generally between 5PF-50PF. Using NPO material or COG material, the higher the accuracy and the better the consistency;

[0047] Comparison circuit 8f, including capacitor C1, can be connected in series with a resistor R1 between C1 and CIN1 channels to enhance anti-interference and stability. The series capacitor C1 needs to use a high-precision capacitor. The accuracy of the capacitor directly determines the accuracy of liquid level detection. Considering some complex and changeable conditions, such as high temperature and high humidity environments, capacitors with less temperature drift coefficients should be used as much as possible, and NPO material capacitors should be used as much as possible. This capacitor is to match the current environment and form a difference with the capacitance of the sensor electrode to determine whether the liquid changes, that is, the sensor capacitance value minus the C1 capacitance value is greater than the set threshold value, to determine whether the container liquid level changes, or whether the container has water changes. Generally, the C1 capacitor needs to use an NPO material capacitor, and the accuracy level should be as high as possible. The value range is determined by the parasitic capacitance of the sensor. It is generally recommended to design between 0PF-10PF. The specific design value is determined by the PCB layout and the sensor.

[0048] In addition, in this embodiment, there is no restriction on the sensor model.

[0049] Obviously, those skilled in the art can make various modifications and changes to the embodiments of the present application without departing from the spirit and scope of the present application. In this way, if these modifications and changes are within the scope of the claims of the present application and their equivalents, the present application is also intended to cover these modifications and changes. The word "comprising" does not exclude the presence of other elements or steps not listed in the claims. The simple fact that certain measures are recorded in mutually different dependent claims does not indicate that the combination of these measures cannot be used to profit. Any figure mark in the claims should not be considered to limit the scope.

Claims

1. A cleaning device for contact liquid level detection, characterized in that: include: A fuselage body, wherein a main control module and a liquid level detection module are integrated in the fuselage body; The liquid level detection module includes: a capacitive liquid level detection chip and a capacitive liquid level detection circuit; A handle and a connecting rod, wherein the handle is detachably arranged on the fuselage body through the connecting rod, and the connecting rod has a retractable structure; A sewage tank, the sewage tank is detachably mounted on the front part of the fuselage body, and the sewage tank comprises a solid-liquid separation chamber and a sewage receiving chamber which are separated into upper and lower parts; A first sensor is disposed at the bottom of the solid-liquid separation chamber, and the first sensor extends into the sewage receiving chamber; A fresh water tank, the fresh water tank being detachably mounted at the rear of the fuselage body; A second sensor is disposed at the bottom of the clean water tank; The first sensor and the second sensor detect the liquid level information in the clean water tank and the sewage holding chamber respectively, and the first sensor and the second sensor transmit the detected liquid level information to the capacitive liquid level detection chip respectively.

2. A cleaning device for contact-type liquid level detection according to claim 1, characterized in that: The first sensor and the second sensor include: a conductive metal sheet, a spring, a conductive tape, a conductive cotton or a thermistor.

3. A cleaning device for contact-type liquid level detection according to claim 2, characterized in that: The liquid level detection circuit includes: a capacitive liquid level detection chip, a comparison circuit, a charge collector, a discharge circuit, an open-drain output circuit, and a decoupling circuit; the first sensor and the second sensor are respectively connected to the capacitive liquid level detection chip, and the capacitive liquid level detection chip is respectively connected to the open-drain output circuit, the comparison circuit, the discharge circuit, the charge collector, and the decoupling circuit.

4. A cleaning device for contact-type liquid level detection according to claim 3, characterized in that: The first sensor and the second sensor are connected to the capacitive liquid level detection chip through R3 respectively, and the resistor R3 is used to improve the conduction anti-interference and radiation anti-interference.

5. A cleaning device for contact-type liquid level detection according to claim 4, characterized in that: The charge collector includes a CMOD capacitor, which is used to collect the change of all parasitic capacitances attached to the capacitance sensor; the discharge circuit includes a CDC discharge capacitor, which is used to discharge the CMOD capacitor.

6. A cleaning device for contact-type liquid level detection according to claim 5, characterized in that: The comparison circuit includes a capacitor C1, one end of which is grounded, and the other end of which is connected to a capacitive liquid level detection chip via R1.

7. A cleaning device for contact-type liquid level detection according to claim 6, characterized in that: The open-drain output circuit is output to the external host device through R4, and needs to be connected to the power supply terminal of the capacitive liquid level detection chip through the pull-up resistor R2.

8. A cleaning device for contact-type liquid level detection according to claim 7, characterized in that: The decoupling circuit includes a capacitor C2, and two ends of the capacitor C2 are respectively connected to a power supply end and a ground end of the capacitive liquid level detection chip.

9. A cleaning device for contact-type liquid level detection according to claim 8, characterized in that: The charge collector is used to collect the change in all parasitic capacitances attached to the sensor, and compares it with the internal comparator of the capacitive liquid level detection chip. When it exceeds the reference voltage set inside the capacitive liquid level detection chip, the CDC discharge capacitor gating switch inside the capacitive liquid level detection chip is turned on to discharge the CMOD capacitor.

10. A cleaning device for contact-type liquid level detection according to claim 9, characterized in that: The capacitive liquid level detection chip converts analog quantities of all additional parasitic capacitance values ​​on the first sensor and the second sensor channels and all additional parasitic capacitance values ​​on the comparison circuit channel into digital quantities of the number of switching times of the CDC discharge capacitor gating switch through the charge and discharge mode.

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