Water pump water shortage protection device and water pump water shortage protection method

Abstract

The present invention provides a water pump water shortage protection device and a water pump water shortage protection method, which are applied to a floor scrubber. The water pump water shortage protection device includes a water pump, a voltage detection module, a power supply component, a water pump power supply module and a control unit; wherein the control unit includes a PID adjustment module, a duty cycle output module, a comparison module and a control module, the PID adjustment module is used to perform PID adjustment on the voltage at both ends of the water pump, so that the voltage at both ends of the water pump is a constant voltage; the duty cycle output module is used to output the real-time duty cycle, the comparison module is used to compare the real-time duty cycle with the preset maximum limit duty cycle, and transmit the comparison result to the control module, and the control module is used to control the water pump power supply module to shut down when the real-time duty cycle is greater than the maximum limit duty cycle, so that the water pump is powered off. Compared with the prior art, the present invention can not only timely and accurately obtain the water shortage state of the water pump and protect it, improve the safety of the floor scrubber, but also has no additional hardware cost.

Description

Technical Field

[0001] The invention relates to a water pump water shortage protection device and a water pump water shortage protection method, belonging to the technical field of automatic control. Background Art

[0002] The water pump of the existing floor scrubber is composed of a solenoid valve, which relies on the water in the water pump for heat dissipation. The water level detector in the water tank detects whether the floor scrubber is short of water and shuts down the water pump when it is short of water. However, this detection method cannot directly detect the water shortage of the water pump. When the water pump is in a waterless or half-water and half-air state not due to water shortage in the water tank, it is very easy to cause the solenoid valve to be unable to dissipate heat. The heat generated by the air suction of the solenoid valve will cause the water pump and adjacent plastic components such as the roller brush to be damaged.

[0003] In view of this, it is indeed necessary to propose improvements to the existing water pump water shortage protection to solve the above problems. Summary of the invention

[0004] The object of the present invention is to provide a water pump water shortage protection device to solve the problem of low reliability of water pump water shortage protection of existing floor scrubbers.

[0005] To achieve the above-mentioned purpose, the present invention provides a water pump water shortage protection device, which is applied to a floor scrubber, and the water pump water shortage protection device comprises: a water pump; a voltage detection module, connected to the water pump, and used to detect the voltage at both ends of the water pump in real time; a power supply component, connected to the water pump, and used to provide electric energy to the water pump; a water pump power supply module, connected between the power supply component and the water pump, so as to conduct or cut off the electrical connection between the powered component and the water pump; and a control unit, respectively connected to the voltage detection module and the water pump power supply module, and used to receive the voltage value at both ends of the water pump detected by the voltage detection module, and detect the voltage value according to the voltage detection module. The control unit comprises a PID adjustment module, a duty cycle output module, a comparison module and a control module, wherein the PID adjustment module is used to perform PID adjustment on the voltage across the water pump so that the voltage across the water pump is a constant voltage; the duty cycle output module is used to output the real-time duty cycle, the comparison module is used to compare the real-time duty cycle with the preset maximum limit duty cycle, and transmit the comparison result to the control module, and the control module is used to control the water pump power supply module to shut down when the real-time duty cycle is greater than the maximum limit duty cycle, so that the water pump is powered off.

[0006] As a further improvement of the present invention, the water pump power supply module includes an electronic switch, and one end of the electronic switch is connected to the power supply component, and the other end is connected to the water pump.

[0007] As a further improvement of the present invention, the electronic switch is communicatively connected with the control module to receive a control signal sent by the control module and is closed or opened according to the control signal.

[0008] As a further improvement of the present invention, the real-time duty cycle is defined as D1, then D1=U / Um, wherein U is a constant voltage, and Um is the voltage at both ends of the water pump detected in real time by the voltage detection module.

[0009] As a further improvement of the present invention, the duty cycle of the water pump when initially started is defined as the initial duty cycle D0, then D0=U / Ue, wherein U is a constant voltage and Ue is a bus voltage of the power supply component.

[0010] As a further improvement of the present invention, the maximum limit duty cycle is a fixed value.

[0011] As a further improvement of the present invention, the maximum limit duty cycle=k*real-time duty cycle, wherein k is a critical coefficient and has a value range of 1.0 to 1.5.

[0012] The purpose of the present invention is to provide a water pump water shortage protection method, which can timely and accurately obtain the water shortage state of the water pump and provide protection, thereby improving the safety of the floor scrubber without additional hardware costs.

[0013] To achieve the above object, the present invention provides a water pump water shortage protection method, which is applied to the above-mentioned water pump water shortage protection device and mainly includes the following steps:

[0014] S1, start the water pump and make the voltage at both ends of the water pump constant;

[0015] S2, the voltage detection module detects the voltage at both ends of the water pump in real time, and the PID adjustment module performs PID adjustment on the voltage at both ends of the water pump to keep it at a constant voltage;

[0016] S3, the duty cycle output module outputs the real-time duty cycle and transmits it to the comparison module, the comparison module compares the real-time duty cycle with the preset maximum limit duty cycle, and transmits the comparison result to the control module;

[0017] S4. When the real-time duty cycle is greater than the maximum limit duty cycle, the control module controls the water pump power supply module to shut down, so that the water pump is powered off.

[0018] As a further improvement of the present invention, in step S1, the water pump is started with an initial duty cycle D0, and the calculation formula of the initial duty cycle D0 is D0=U / Ue, wherein U is a constant voltage and Ue is a bus voltage of the power supply component.

[0019] As a further improvement of the present invention, the step S4 further includes: when the real-time duty cycle is continuously greater than the maximum limit duty cycle within a set time period, the control module controls the water pump power supply module to shut down, so that the water pump is powered off.

[0020] As a further improvement of the present invention, the set time period is 200ms to 1s.

[0021] The beneficial effects of the present invention are as follows: the present invention utilizes a duty cycle output module to output a real-time duty cycle, so that whether the water pump is short of water can be judged based on a comparison result between the real-time duty cycle and the maximum limit duty cycle. This not only enables timely and accurate acquisition of the water shortage status of the water pump and protection thereof, thereby improving the safety of the floor scrubber, but also eliminates the need for a separate sensor and generates no additional hardware costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural block diagram of a water pump water shortage protection device in accordance with a preferred embodiment of the present invention.

[0023] Figure 2 yes Figure 1 A structural block diagram of a preferred embodiment of the control unit in FIG.

[0024] Figure 3 It is a flow chart of the water pump water shortage protection method of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] It should be noted here that in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the scheme of the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0027] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0028] like Figure 1 and Figure 2As shown, the present invention provides a water pump water shortage protection device, including a water pump 10, a voltage detection module 20, a power supply component 30, a control unit 40 and a water pump power supply module 50. Among them, the power supply component 30 is connected to the water pump 10, and is used to provide electric energy to the water pump 10; the voltage detection module 20 is connected to the water pump 10, and is used to detect the voltage at both ends of the water pump 10 in real time; the control unit 40 is respectively connected to the voltage detection module 20 and the water pump power supply module 50, and is used to receive the voltage value at both ends of the water pump 10 detected by the voltage detection module 20, and output a control signal to the water pump power supply module 50 according to the voltage value; the water pump power supply module 50 is connected between the power supply component 30 and the water pump 10, and is used to conduct or cut off the electrical connection between the power supply component 30 and the water pump 10, so that the water pump 10 is powered on or off.

[0029] In a preferred embodiment of the present invention, the power supply component 30 is a battery pack, and the water pump water shortage protection device is applied to a floor scrubber. Of course, the water pump water shortage protection device of the present invention can also be applied to other equipment with a water pump, which is not limited here.

[0030] Specifically, the control unit 40 includes a PID adjustment module 41, a duty cycle output module 42, a comparison module 43 and a control module 44, wherein the PID adjustment module 41 is connected to the voltage detection module 20 and the control module 44, and is used to perform PID adjustment on the voltage across the water pump 10, so that the voltage across the water pump 10 is a constant voltage U. The duty cycle output module 42 is connected to the control module 44 and the comparison module 43, and is used to output a real-time duty cycle D1 when the water pump 10 is operating normally, and the comparison module 43 is used to compare the real-time duty cycle D1 with a preset maximum limit duty cycle Dmax, and transmit the comparison result to the control module 44, and the control module 44 is used to control the water pump power supply module 50 to shut down when the real-time duty cycle D1 is greater than the maximum limit duty cycle Dmax, so that the water pump 10 is powered off.

[0031] The water pump power supply module 50 includes an electronic switch (not shown), and one end of the electronic switch is connected to the power supply component 30 and the other end is connected to the water pump 10. At the same time, the electronic switch is also connected to the control module 44 in communication, so that the electronic switch can receive the control signal sent by the control module 44, and close or open according to the control signal, so as to realize the electrical conduction or disconnection between the power supply component 30 and the water pump 10. That is, when the electronic switch is closed, the power supply component 30 is electrically connected to the water pump 10, and the power supply component 30 supplies power to the water pump 10, so that the water pump 10 can work normally; when the electronic switch is opened, the power supply component 30 is disconnected from the water pump 10, and the power supply component 30 stops supplying power to the water pump 10, and the water pump 10 is powered off.

[0032] During the normal operation of the water pump 10, the calculation formula of the real-time duty cycle D1 is: D1 = U / Um, where U is a constant voltage and Um is the voltage across the water pump 10 detected in real time by the voltage detection module 20. The purpose of setting the real-time duty cycle D1 is that when the water tank is full of water, the water pump 10 starts, and the water pump 10 is in a rated load operation state. After the water pump 10 discharges part of the water, the water pump 10 is in a half-water and half-air state, and the load of the water pump 10 is less than the rated load. If you want to automatically determine the drainage situation in the water tank without manual work, you need to determine the load situation of the water pump 10. In the case of omitting the water level detector, the best choice is to make a judgment based on the change of the voltage value across the water pump 10. In other words, you can set a coefficient (preferably a duty cycle) to determine whether the water pump 10 is in a water shortage state based on the change of the coefficient.

[0033] Back to the present embodiment, when the real-time duty cycle D1 is greater than the maximum limit duty cycle Dmax, it is determined that the water pump 10 is in a waterless state or a half-water and half-air state (i.e., a water shortage state), and the control module 44 outputs a control signal to the water pump power supply module 50 to drive the electronic switch to disconnect, so that the water pump 10 is powered off; when the real-time duty cycle D1 is less than or equal to the maximum limit duty cycle Dmax, it is determined that the water pump 10 is not in a water shortage state, and at this time the control module 44 outputs a control signal to the water pump power supply module 50 to drive the electronic switch to remain in a closed state, and the water pump 10 continues to operate. It can be seen that the present invention uses the real-time duty cycle D1 to compare with the maximum limit duty cycle Dmax, which can quickly determine the load condition of the water pump 10, and then determine whether the water pump 10 is in a water shortage state, and has the advantages of simple implementation and low implementation cost.

[0034] Preferably, the maximum limit duty cycle Dmax is a fixed value. Of course, in other embodiments, the maximum limit duty cycle Dmax can also be calculated by the calculation formula Dmax=k*D1, where k is a critical coefficient with a value range of 1.0 to 1.5. Of course, the value of the critical coefficient k can also be calculated based on the size of the initial duty cycle D0 when the water pump 10 is initially started. At this time, the calculation formula of the maximum limit duty cycle Dmax can be adjusted to Dmax=k(D0)*D1.

[0035] When the water pump 10 is initially started, the duty cycle output module 42 may output an initial duty cycle D0 to drive the water pump power supply module 50 to conduct until the voltage across the water pump 10 is maintained at a constant voltage U. The calculation formula for the initial duty cycle D0 is D0=U / Ue, where U is a constant voltage and Ue is a bus voltage of the power supply component 30, i.e., the nominal full pack voltage of the battery pack. Of course, the calculation method for the initial duty cycle D0 when the water pump 10 is initially started may also be other, which will not be described here.

[0036] like Figure 3 As shown in FIG. 1 , it is a flow chart of the water pump water shortage protection method of the present invention. It can be seen from the flow chart that the water pump water shortage protection method of the present invention mainly includes the following steps:

[0037] S1, start the water pump 10, and make the voltage across the water pump 10 a constant voltage U;

[0038] S2, the voltage detection module 20 performs real-time detection on the voltage at both ends of the water pump 10, and the PID adjustment module 41 performs PID adjustment on the voltage at both ends of the water pump 10 to maintain it at a constant voltage U;

[0039] S3, the duty cycle output module 42 outputs the real-time duty cycle D1 and transmits it to the comparison module 43, the comparison module 43 compares the real-time duty cycle D1 with the preset maximum limit duty cycle Dmax, and transmits the comparison result to the control module 44;

[0040] S4. When the real-time duty cycle D1 is greater than the maximum limit duty cycle Dmax, the control module 44 controls the water pump power supply module 50 to shut down, so that the water pump 10 is powered off.

[0041] Preferably, in step S1, the water pump 10 is started with an initial duty cycle D0, and the calculation formula of the initial duty cycle D0 is D0=U / Ue, wherein U is a constant voltage and Ue is a bus voltage of the power supply component 30, that is, the nominal full pack voltage of the battery pack.

[0042] Step S4 also includes: when the real-time duty cycle D1 is continuously greater than the maximum limit duty cycle Dmax within a set time period, the control module 44 outputs a control signal to the water pump power supply module 50, so that the electronic switch is disconnected and the water pump 10 is powered off. Preferably, the set time period is 200ms to 1s. In other words, as long as the real-time duty cycle D1 is continuously greater than the maximum limit duty cycle Dmax within 200ms to 1s, no other judgment or operation is required, and the control module 44 directly controls the water pump 10 to power off.

[0043] In short, the present invention provides a simple, low-cost water pump water shortage protection solution, which uses an electronic switch to control the operation and power-off of the water pump 10. After the water pump 10 is normally started, the control unit 40 controls the electronic switch to perform pulse width modulation to control the output of the real-time duty cycle D1, so as to ensure that the water pump 10 can operate at a constant voltage U. On this basis, the control unit 40 determines whether the water pump 10 is in a water shortage state according to the size relationship between the real-time duty cycle D1 and the maximum limit duty cycle Dmax (i.e., the continuous change of the real-time duty cycle D1). When it is determined that the water pump 10 is in a water shortage state, the electrical connection between the power supply component 30 and the water pump 10 can be quickly cut off to cut off the power supply of the water pump 10, which plays a good monitoring and protection role in the water shortage of the water pump 10.

[0044] In summary, the present invention utilizes the duty cycle output module 42 to output the real-time duty cycle D1, so that whether the water pump 10 is in a water shortage state can be judged according to the comparison result between the real-time duty cycle D1 and the maximum limit duty cycle Dmax. This not only can timely and accurately obtain the water shortage state of the water pump 10 and protect it, thereby improving the safety of the floor scrubber, but also does not require a separate sensor and does not incur additional hardware costs.

[0045] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A water pump water shortage protection device, applied to a floor scrubber, characterized in that: The water pump water shortage protection device comprises: Water pump; A voltage detection module, connected to the water pump, for detecting the voltage across the water pump in real time; A power supply component, connected to the water pump, for providing electrical energy to the water pump; a water pump power supply module, connected between the power supply component and the water pump to conduct or cut off the electrical connection between the power supply component and the water pump; and A control unit, connected to the voltage detection module and the water pump power supply module respectively, for receiving the voltage value at both ends of the water pump detected by the voltage detection module, and outputting a control signal to the water pump power supply module according to the voltage value; Wherein, the control unit includes a PID adjustment module, a duty cycle output module, a comparison module and a control module. The PID adjustment module is connected to the voltage detection module and the control module, and is used to perform PID adjustment on the voltage at both ends of the water pump so that the voltage at both ends of the water pump is a constant voltage; the duty cycle output module is connected to the control module and the comparison module, and is used to output a real-time duty cycle. The comparison module is used to compare the real-time duty cycle with a preset maximum limit duty cycle, and transmit the comparison result to the control module. The control module is used to control the water pump power supply module to shut down when the real-time duty cycle is greater than the maximum limit duty cycle, so that the water pump is powered off; the real-time duty cycle is defined as D1, then D1=U / Um, wherein U is a constant voltage, and Um is the voltage at both ends of the water pump detected in real time by the voltage detection module.

2. The water pump water shortage protection device according to claim 1 is characterized in that: The water pump power supply module includes an electronic switch, and one end of the electronic switch is connected to the power supply component, and the other end is connected to the water pump.

3. The water pump water shortage protection device according to claim 2 is characterized in that: The electronic switch is communicatively connected with the control module to receive a control signal sent by the control module and is closed or opened according to the control signal.

4. The water pump water shortage protection device according to claim 1, characterized in that: The duty cycle of the water pump when it is initially started is defined as the initial duty cycle D0, then D0=U / Ue, wherein U is a constant voltage and Ue is a bus voltage of the power supply component.

5. The water pump water shortage protection device according to claim 1, characterized in that: The maximum limit duty cycle is a fixed value.

6. The water pump water shortage protection device according to claim 1, characterized in that: The preset maximum limit duty cycle=k*real-time duty cycle, wherein k is a critical coefficient and has a value range of 1.0 to 1.

5.

7. A water pump water shortage protection method, applied to the water pump water shortage protection device according to any one of claims 1 to 6, characterized in that: The water pump water shortage protection method mainly comprises the following steps: S1, start the water pump and make the voltage at both ends of the water pump constant; S2, the voltage detection module detects the voltage at both ends of the water pump in real time, and the PID adjustment module performs PID adjustment on the voltage at both ends of the water pump to keep it at a constant voltage; S3, the duty cycle output module outputs the real-time duty cycle and transmits it to the comparison module, the comparison module compares the real-time duty cycle with the preset maximum limit duty cycle, and transmits the comparison result to the control module; S4. When the real-time duty cycle is greater than the maximum limit duty cycle, the control module controls the water pump power supply module to shut down, so that the water pump is powered off.

8. The water pump water shortage protection method according to claim 7, characterized in that: In step S1 , the water pump is started with an initial duty cycle D0 , and the calculation formula of the initial duty cycle D0 is D0=U / Ue, wherein U is a constant voltage and Ue is a bus voltage of the power supply component.

9. The water pump water shortage protection method according to claim 7, characterized in that: The step S4 also includes: when the real-time duty cycle is continuously greater than the maximum limit duty cycle within a set time period, the control module controls the water pump power supply module to shut down, so that the water pump is powered off.

10. The water pump water shortage protection method according to claim 9, characterized in that: The set time period is 200ms to 1s.

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