A water pump anti-dry-burning protection device and a pumping system equipped with the device

Abstract

This utility model provides a water pump anti-dry-burning protection device and a pumping system equipped with the device. The anti-dry-burning protection device includes a vacuum tank, a pressure detection unit, a first relay, and a control circuit. The vacuum tank is connected to the water pump and a water collection device. The pressure detection unit is connected to the vacuum tank and is used to detect the pressure inside the vacuum tank. The first relay is connected to the pressure detection unit. The control circuit is connected to the first relay and the water pump and is used to output a stop signal to control the water pump to stop. The beneficial effects of this utility model are that it effectively solves the technical problem of water pump dry-burning caused by poor water priming, resulting in water pump damage; it extends the service life of the water pump; reduces maintenance costs; improves the timeliness of protection; enhances the protection effect; achieves strong and weak current isolation; reduces the risk of electric shock; and allows free switching of working modes, ensuring the normal operation of the initial water priming.

Description

Technical Field

[0001] This utility model belongs to the technical field of water pumping equipment, and in particular relates to a water pump anti-dry burning protection device and a water pumping system equipped with the device. Background Technology

[0002] The pumping system in wastewater treatment equipment is an electromechanical system used to collect and transport wastewater that cannot be discharged by gravity. In existing technology, the pumping system includes a water pump, a water intake pipe, a water collection device, a level sensor, and a control unit. The water pump and the water collection device are connected by the water intake pipe. The level sensor detects the liquid level in the water collection device. When the liquid level is too low, the control unit stops the water pump to prevent it from running dry due to insufficient water intake. However, if the water intake pipe is poorly sealed or blocked, the water pump cannot perform normal water intake. In this case, the level sensor detects a normal liquid level, and the control unit keeps the pump running, causing it to run dry due to lack of water. This can lead to pump damage, such as mechanical seal burnout due to high temperature, impeller and pump shaft wear, and damage to the pump body liner, requiring frequent replacement and increasing maintenance costs. Utility Model Content

[0003] To solve the above-mentioned technical problems, this utility model provides a water pump anti-dry-burning protection device and a water pumping system equipped with the device, which effectively solves the technical problem that the water pump cannot automatically stop when the water priming is not smooth, resulting in water pump dry burning and water pump damage, and increased maintenance costs, thus overcoming the shortcomings of the prior art.

[0004] The technical solution adopted in this utility model is: a water pump anti-dry-burning protection device, comprising,

[0005] Vacuum tank, connected to water pump and water collection device;

[0006] A pressure detection unit, connected to the vacuum tank, is used to detect the pressure inside the vacuum tank;

[0007] The first relay is connected to the pressure detection unit;

[0008] A control circuit, connected to the first relay and the water pump, is used to output a stop signal to control the water pump to stop.

[0009] Furthermore, the pressure detection unit is configured as an electrical contact pressure gauge. When the pressure detected by the electrical contact pressure gauge is greater than a set threshold, the first relay is energized to cause the control circuit to output a shutdown signal to control the water pump to stop.

[0010] Furthermore, the first relay includes a first coil and a first contact, the first coil being connected in series with the pressure detection unit, and the first contact being connected in series with the control circuit.

[0011] Furthermore, a switch is connected in series with the first contact for switching the operating mode.

[0012] Furthermore, the switching switch is configured as a two-contact rotary switch.

[0013] Furthermore, it also includes a thermal relay, which is connected to the water pump and the control circuit, and is connected in parallel with the first contact.

[0014] Furthermore, it also includes a first power supply and a second power supply, the first power supply being connected to the pressure detection unit and the first coil, and the second power supply being connected to the first contact and the thermal relay.

[0015] Furthermore, the first power supply is set to a 24V DC power supply, and the second power supply is set to a 220V AC power supply.

[0016] Furthermore, it also includes a second relay connected in series with the control circuit.

[0017] This utility model also provides a water pumping system, which is equipped with the water pump anti-dry-burn protection device as described above.

[0018] The advantages and positive effects of this utility model are as follows: By adopting the above-mentioned technical solution and setting a pressure detection unit to detect the negative pressure state inside the negative pressure tank, the technical problem of water pump dry burning caused by poor water priming due to low liquid level, poor sealing effect or blockage of water priming pipeline is effectively solved, thus extending the service life of the water pump and reducing maintenance costs. The negative pressure state of the vacuum pressure tank directly represents the water priming success rate, triggering an electrical interlock shutdown. The vacuum pressure signal directly drives the hardware interlock, avoiding delays in software program judgment and improving the timeliness of protection. Independent detection of both water pump dry burning and motor overload faults is achieved; shutdown is triggered by either fault, improving the protection effect. By setting dual power supplies, with low-voltage DC controlling high-voltage AC circuit, strong and weak current isolation is achieved, ensuring electrical isolation between the pressure detection unit and the control circuit. This reduces electromagnetic interference from the control circuit to the pressure detection unit, ensures the detection accuracy of the pressure detection unit, and reduces the risk of electric shock. By setting a switch, the operating mode can be freely switched. In manual mode, the pressure detection signal is disabled to ensure the normal operation of the initial water priming. After the vacuum state is established, it switches to automatic mode to achieve automatic detection during the water priming process. The water pump can be stopped by controlling the fault input terminal of the PLC controller without modifying the existing control program. Attached Figure Description

[0019] The above and other objects, features, and advantages of this utility model will become more apparent from the more detailed description of the embodiments thereof in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this utility model and form part of the specification. They are used together with the embodiments of this utility model to explain the utility model and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same parts or steps.

[0020] Figure 1 This is a schematic diagram of the structure and installation of a water pump anti-dry-burning protection device according to an embodiment of this utility model.

[0021] Figure 2 This is a circuit connection diagram of a water pump anti-dry-burning protection device according to an embodiment of the present invention.

[0022] In the picture:

[0023] 1. Vacuum tank 2. Pressure detection unit 3. Water pump

[0024] 4. Water collection device 5. Water intake pipeline

[0025] KA1, first coil KA1-1, first contact SW, electrical contact

[0026] SA, changeover switch KA3-1, thermal relay contact KA2, second coil

[0027] KA2-1, Second Contact Detailed Implementation

[0028] This utility model provides a water pump anti-dry-burning protection device and a water pumping system equipped with the device. The embodiments of this utility model will be described below with reference to the accompanying drawings.

[0029] In the description of the embodiments of this utility model, it should be understood that the terms "top," "bottom," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, it should be noted that unless otherwise expressly specified and limited, the terms "set" and "connected" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication of two elements. Those skilled in the art can understand the specific meaning of the above terms in this utility model through specific circumstances.

[0030] like Figure 1 and Figure 2As shown in the figure, an embodiment of this utility model discloses a water pump anti-dry-burning protection device, including a vacuum tank 1, a pressure detection unit 2, a first relay, and a control circuit. The vacuum tank 1 is installed on the water inlet pipe 5 between the water pump 3 and the water collection device 4, and is connected to both the water pump 3 and the water collection device 4. The pressure detection unit 2 is connected to the vacuum tank 1 and is used to detect the pressure inside the vacuum tank 1. The first relay is connected to the pressure detection unit 2. The control circuit is connected to the first relay and the water pump 3, and is used to output a stop signal to control the water pump 3 to stop. In this application's technical solution, the negative pressure state of the vacuum tank 1 is detected to monitor whether the water pump 3 is drawing water normally. Compared with the prior art that uses liquid level detection to control the start and stop of the water pump 3, whether the liquid level is too low, the sealing effect of the water inlet pipe 5 is poor, or it is blocked, as long as water drawing is not smooth, the pressure detection unit 2 can detect the pressure change inside the vacuum tank 1, enabling the control circuit to control the water pump 3, thereby protecting the water pump 3 and extending its service life.

[0031] Specifically, pressure detection unit 2 is configured as an electrical contact pressure gauge. When the pressure detected by the electrical contact pressure gauge exceeds a set threshold, the first relay is energized, causing the control circuit to output a stop signal to control the water pump 3 to stop. An electrical contact pressure gauge is a pressure measuring instrument that can automatically connect or disconnect a circuit when the pressure reaches a set value. In some embodiments, the electrical contact SW of the electrical contact pressure gauge is configured as a normally open contact. When the electrical contact pressure gauge detects that the pressure inside the vacuum tank 1 exceeds the set threshold, the electrical contact SW closes, energizing the first relay, thereby connecting the control circuit and causing the control circuit to output a stop signal to control the water pump 3 to stop. The electrical contact pressure gauge integrates both pressure measurement and switching control functions, achieving simple and reliable automated control through the combination of mechanical and electrical methods. The electrical contact pressure gauge is existing technology; its specific structure and connection method will not be described in detail here.

[0032] Specifically, the first relay includes a first coil KA1 and a first contact KA1-1. The first coil KA1 is connected in series with the pressure detection unit, and the first contact KA1-1 is connected in series with the control circuit. In some embodiments, the pressure detection unit is configured as an electrical contact pressure gauge, and the first coil KA1 is connected in series with the electrical contact SW of the pressure gauge. When the pressure gauge detects that the pressure inside the vacuum tank 1 is greater than a set threshold, the electrical contact SW changes from a normally open state to a closed state, energizing the first coil KA1, thereby causing the first contact KA1-1 to close and connecting the control circuit connected in series with the first contact KA1-1. By setting the first relay, the pressure detection unit 2 and the control circuit are electrically isolated, reducing electromagnetic interference from the control circuit to the pressure detection unit 2 and ensuring the detection accuracy of the pressure detection unit 2.

[0033] Optionally, a switch SA is connected in series with the first contact KA1-1 for switching operating modes. During the initial priming of water pump 3, it takes a certain amount of time for the vacuum tank 1 to establish a vacuum. If the pressure detection unit 2 is used directly, the pressure value inside the vacuum tank 1 will exceed the set threshold, causing the first relay to energize and the control circuit to activate, resulting in an erroneous shutdown. Therefore, the switch SA is used to distinguish between the initial priming and the priming process. The switch SA has both manual and automatic operating modes. During the initial priming, the switch SA is switched to manual mode, disconnecting the connection circuit of the first contact KA1-1, keeping the first contact KA1-1 in an open state, shielding the detection signal from the pressure detection unit 2, ensuring that water pump 3 primes normally for the first time and establishes a negative pressure environment in the vacuum tank 1. After the initial priming is normal, the switch SA is switched to automatic mode, connecting the connection circuit of the first contact KA1-1, allowing the pressure detection unit 2 to transmit its detection signal. By using the switch SA to switch between different operating modes, both the normal operation of the initial priming and detection during the priming process can be ensured.

[0034] Preferably, the toggle switch SA is configured as a double-contact rotary switch. Ordinary single-contact switches only disconnect a single contact in manual mode, and parasitic current can still cause false triggering. However, with a double-contact rotary switch, both contacts are physically disconnected in manual mode, resulting in very low parasitic current and eliminating the possibility of false triggering. Furthermore, the two contacts are connected in parallel to carry the current, so the function can still be maintained even if a single contact fails.

[0035] Optionally, a thermal relay is also included. This thermal relay is connected to the water pump 3 and the control circuit, and is in parallel with the first contact KA1-1. When the water pump 3 motor experiences an overload (i.e., the current exceeds the rated value), failure to stop the pump in time may result in motor burnout or mechanical damage. By setting up the thermal relay, when the motor is overloaded, the thermal relay contact KA3-1 closes, connecting the control circuit and stopping the water pump 3. The thermal relay, connected in parallel with the first contact KA1-1, enables independent detection of both dry running and motor overload faults in the water pump 3. Either fault triggers an immediate shutdown, improving the protection effect.

[0036] Specifically, it also includes a first power supply and a second power supply. The first power supply is connected to the pressure detection unit 2 and the first coil KA1, while the second power supply is connected to the first contact KA1-1 and the thermal relay. The first power supply is set to 24V DC, and the second power supply is set to 220V AC. The pressure detection unit 2 and the first coil KA1 are powered by 24V DC, while the first contact KA1-1 and the thermal relay are powered by 220V AC. This low-voltage DC control of the high-voltage AC circuit achieves strong and weak current isolation, eliminating the risk of electric shock.

[0037] Specifically, it also includes a second relay, which is connected in series with the control circuit. The second relay includes a second coil KA2 and a second contact KA2-1. The control circuit includes a PLC controller. The second coil KA2 is connected in series with a parallel circuit of a thermal relay and a first contact KA1-1. The second contact KA2-1 is connected to the fault input terminal of the PLC controller. If the water flow is obstructed during operation, causing the first contact KA1-1 to close, or if the motor is overloaded, causing the thermal relay contact KA3-1 to close, the second coil KA2 will be energized. The second contact KA2-1 will then close, connecting the fault input terminal of the PLC controller, which will immediately stop the water pump 3.

[0038] A water pumping system includes a water pump 3, a water collection device 4, a water inlet pipe 5, and a water pump anti-dry-burning device as described above. By installing the water pump anti-dry-burning device, dual fault detection and protection against water pump 3 dry-burning and motor overload are achieved, ensuring the normal operation of the water pumping system. In the water pumping system, multiple water pump anti-dry-burning devices can be installed according to the number of water pumps 3, with one device corresponding to each water pump 3. In some feasible embodiments, the connection circuit of the anti-dry-burning device can be integrated into a control box. This water pumping system is not only applicable to wastewater treatment but can be used in any technical field where liquids cannot be transported by gravity.

[0039] Example: A water pump anti-dry-burning protection device includes a vacuum tank 1, a pressure detection unit 2, a first relay, a thermal relay, a second relay, and a control circuit. The vacuum tank 1 is installed on the water inlet pipe 5 between the water pump 3 and the water collection device 4, and is connected to both the water pump 3 and the water collection device 4. The pressure detection unit 2 is connected to the vacuum tank 1 and is used to detect the pressure inside the vacuum tank 1. The first relay is connected to the pressure detection unit 2. The control circuit is connected to the first relay and the water pump 3, and is used to output a stop signal to control the water pump 3 to stop. The pressure detection unit 2 is configured as an electrical contact pressure gauge. When the pressure detected by the electrical contact pressure gauge exceeds a set threshold, the first relay is energized, causing the control circuit to output a stop signal to control the water pump 3 to stop. The first relay includes a first coil KA1 and a first contact KA1-1. The first coil KA1 is connected in series with the electrical contact SW of the electrical contact pressure gauge, and the first contact KA1-1 is connected in series with the control circuit. A switching switch SA is connected in series with the first contact KA1-1 for switching the operating mode. The switching switch SA is configured as a double-contact rotary switch. The thermal relay contact KA3-1 is connected to the water pump 3 and the control circuit, and is connected in parallel with the first contact KA1-1 for overload protection of the water pump 3 motor. The pressure detection unit 2 and the first coil KA1 are powered by a 24V DC power supply, while the first contact KA1-1 and the thermal relay are powered by a 220V AC power supply. The second relay is connected in series with the control circuit. The second relay includes a second coil KA2 and a second contact KA2-1. The control circuit includes a PLC controller. The second coil KA2 is connected in series with the parallel circuit of the thermal relay and the first contact KA1-1, and the second contact KA2-1 is connected to the fault input terminal of the PLC controller.

[0040] When water pump 3 starts for the initial priming, the establishment of negative pressure in vacuum tank 1 takes a certain amount of time. During this time, the pressure detected by the pressure gauge exceeds the set threshold, causing the electrical contact SW to close, energizing the first coil KA1 and closing the first contact KA1-1. To prevent accidental shutdown, the operator switches the selector switch SA to manual mode, physically disconnecting the two contacts and cutting off the connection circuit of the first contact KA1-1, thus placing KA1-1 in the open state and shielding the pressure gauge's detection signal. Water pump 3 then starts normally for the initial priming, establishing a negative pressure environment in vacuum tank 1. Simultaneously, the thermal relay monitors the motor current in real time. If there is no overload, the thermal relay contacts remain open, the second relay does not activate, the PLC controller has no fault input, and water pump 3 performs normal priming.

[0041] After the negative pressure inside vacuum tank 1 stabilizes, the pressure detected by the pressure gauge is less than the set threshold, and the pressure gauge SW opens. The operator switches the changeover switch SA to automatic mode, and the double contacts of the double-contact rotary switch close, making the connection circuit of the first contact KA1-1 conductive. If, during the operation of water pump 3, the water level is too low, the sealing effect of the water inlet pipe 5 is poor, or a blockage occurs, causing poor water flow, the vacuum state inside vacuum tank 1 changes. When the pressure detected by the pressure gauge exceeds the set threshold, the pressure gauge SW immediately closes, energizing the first coil KA1. The first contact KA1-1 closes, energizing the second coil KA2 of the second relay. The second contact KA2-1 of the second relay closes, connecting the fault input terminal of the PLC controller, and the PLC controller immediately stops water pump 3. If the motor is overloaded, the thermal relay contact KA3-1 closes, energizing the second coil KA2 of the second relay. The second contact KA2-1 of the second relay closes, connecting the fault input terminal of the PLC controller, and the PLC controller immediately stops water pump 3.

[0042] The advantages and positive effects of this utility model are:

[0043] 1. By setting up a pressure detection unit to detect the negative pressure status inside the negative pressure tank, the technical problem of water pump dry burning caused by poor water diversion due to low liquid level, poor sealing effect or blockage of water diversion pipeline is effectively solved, thus extending the service life of water pump and reducing maintenance costs.

[0044] 2. The success rate of water priming is directly characterized by the negative pressure state of the vacuum pressure tank, triggering an electrical interlock shutdown. The vacuum pressure signal directly drives the hardware interlock, avoiding the delay of software program judgment and improving the timeliness of protection.

[0045] 3. Independent detection of both pump dry running and motor overload faults has been achieved, and the machine will stop immediately when either fault is triggered, thus improving the protection effect.

[0046] 4. By setting up dual power supplies, with low-voltage DC controlling high-voltage AC circuit, strong and weak current isolation is achieved, which enables electrical isolation between the pressure detection unit and the control circuit, reduces electromagnetic interference from the control circuit to the pressure detection unit, ensures the detection accuracy of the pressure detection unit, and reduces the risk of electric shock.

[0047] 5. By setting a switching switch, the working mode can be freely switched. In manual mode, the pressure detection signal is blocked to ensure the normal progress of the first water priming. After the vacuum state is established, it switches to automatic mode to realize automatic detection during the water priming process.

[0048] 6. The water pump can be stopped by controlling the fault input terminal of the PLC controller without modifying the existing control program.

[0049] The embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. It should be noted that implementations not illustrated or described in the drawings or the main text of the specification are forms known to those skilled in the art and have not been described in detail. Furthermore, the definitions of the various components described above are not limited to the specific structures, shapes, or methods mentioned in the embodiments, and those skilled in the art can easily modify or substitute them.

[0050] The embodiments of this utility model have been described in detail above, but the content described is only a preferred embodiment of this utility model and should not be considered as limiting the scope of implementation of this utility model. All equivalent changes and improvements made in accordance with the claims of this utility model should still fall within the patent coverage of this utility model.

Claims

1. A water pump anti-dry-burning protection device, characterized in that: include, Vacuum tank, connected to water pump and water collection device; A pressure detection unit, connected to the vacuum tank, is used to detect the pressure inside the vacuum tank; The first relay is connected to the pressure detection unit; A control circuit, connected to the first relay and the water pump, is used to output a stop signal to control the water pump to stop.

2. The water pump anti-dry-burning protection device according to claim 1, characterized in that: The pressure detection unit is set as an electric contact pressure gauge. When the pressure detected by the electric contact pressure gauge is greater than a set threshold, the first relay is energized to cause the control circuit to output a stop signal to control the water pump to stop.

3. The water pump anti-dry-burning protection device according to claim 1, characterized in that: The first relay includes a first coil and a first contact. The first coil is connected in series with the pressure detection unit, and the first contact is connected in series with the control circuit.

4. The water pump anti-dry-burning protection device according to claim 3, characterized in that: The first contact is connected in series with a switch for switching the working mode.

5. A water pump anti-dry-burning protection device according to claim 4, characterized in that: The switching switch is configured as a two-contact rotary switch.

6. A water pump anti-dry-burning protection device according to claim 3, characterized in that: It also includes a thermal relay, which is connected to the water pump and the control circuit, and is connected in parallel with the first contact.

7. A water pump anti-dry-burning protection device according to claim 6, characterized in that: It also includes a first power supply and a second power supply, the first power supply being connected to the pressure detection unit and the first coil, and the second power supply being connected to the first contact and the thermal relay.

8. A water pump anti-dry-burning protection device according to claim 7, characterized in that: The first power supply is set to a 24V DC power supply, and the second power supply is set to a 220V AC power supply.

9. A water pump anti-dry-burning protection device according to any one of claims 1-8, characterized in that: It also includes a second relay, which is connected in series with the control circuit.

10. A pumping system, characterized in that: The water pump is equipped with a dry-burn protection device as described in any one of claims 1-9.

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