A hot water circulation pump and a control method for low cavitation hot water circulation

Abstract

The present invention belongs to the technical field of water pumps, and specifically relates to a hot water circulation pump and a control method for low cavitation hot water circulation, comprising a first motor, a coupling assembly and a pump body, wherein the coupling assembly is installed between the first motor and the pump body; a water inlet chamber and a water outlet chamber are respectively provided on both sides of the top of the pump body, and an impeller chamber is provided inside the first motor and below the water outlet chamber; and an inlet and outlet water regulating module is installed in the water inlet chamber and the water outlet chamber. The invention changes the internal structure of the pump body and the impeller structure so that the diameter of the water inlet and outlet of the pump body can be adjusted, and at the same time, the blades of the impeller can be deflected at an angle, and the water inlet and outlet of different diameters and the blades of different angles are adjusted according to the different rotation speeds of the impeller to adapt to the flow direction and velocity distribution of the liquid under different rotation speeds of the impeller, thereby reducing the local pressure drop and further reducing the risk of cavitation.

Description

Technical Field

[0001] The invention belongs to the technical field of water pumps, and in particular relates to a hot water circulation pump and a control method for low-cavitation hot water circulation. Background Art

[0002] A hot water circulation pump is a device that provides energy through a power device to keep water flowing in a closed-loop system. Its core components include an electric motor and an impeller. The impeller is driven by the electric motor to rotate, forming a negative pressure area to suck in and accelerate the water, and then the water is pushed into the system through the extrusion chamber. This process ensures that hot water continues to flow in the pipe, avoids the water temperature from dropping due to local stagnation, and ensures the efficiency and stability of the heating system. In homes, commercial buildings and industrial applications, hot water circulation pumps play a key role. It can not only improve the efficiency of hot water supply and reduce the waiting time for hot water, but also save water resources and energy. In addition, the use of hot water circulation pumps can also help extend the service life of equipment such as water heaters. , reduce the maintenance cost of equipment, and cavitation refers to the vaporization of water and the formation of bubbles during the operation of the water pump due to the local pressure being lower than the saturated vapor pressure of water. When these bubbles enter the high-pressure area with the water flow, they will quickly collapse and generate shock waves, causing damage to the pump body material. This phenomenon is cavitation. Cavitation usually occurs at the inlet of the pump and on components such as the impeller, especially when pumping high-temperature, low-boiling-point media. Cavitation will have many adverse effects on the hot water circulation pump. It will accelerate the damage of the pump casing and impeller, shorten the service life of the pump, and cause the performance of the pump to decline, such as reduced head, flow and efficiency. Cavitation will also increase the vibration and noise of the pump, affecting the normal operation and working environment of the pump; In the design and application of existing hot water circulation pumps, it is often difficult to completely avoid the occurrence of cavitation, especially when transporting high-temperature, low-boiling point media, the cavitation problem is more prominent. In addition, the design of existing pumps focuses more on improving energy efficiency and flow, while there is relatively little optimization in anti-cavitation performance. In the adjustment of impeller speed, the blade angle cannot fully adapt to the changed speed, which will cause uneven distribution of internal pressure inside the pump body, making cavitation more likely to occur. Summary of the invention

[0003] The object of the present invention is to provide a hot water circulation pump and a control method for low cavitation hot water circulation. By changing the internal structure of the pump body and the impeller structure, the diameter of the water inlet and outlet of the pump body can be adjusted, and the blades of the impeller can be deflected at an angle. According to the different rotation speeds of the impeller, the water inlet and outlet diameters and the blades at different angles are adjusted to adapt to the flow direction and velocity distribution of the liquid under different impeller rotation speeds, thereby reducing the local pressure drop and further reducing the risk of cavitation.

[0004] The technical solution adopted by the present invention is as follows: A hot water circulation pump and a control method for low cavitation hot water circulation, comprising a first motor, a coupling assembly and a pump body, wherein the coupling assembly is installed between the first motor and the pump body; A water inlet cavity and a water outlet cavity are respectively provided on both sides of the top of the pump body, and an impeller cavity is provided inside the first motor and below the water outlet cavity; An inlet and outlet water regulating module, the inlet and outlet water regulating module is installed in the water inlet cavity and the water outlet cavity, the inlet and outlet water regulating module comprises two inlet and outlet regulating disks, the two inlet and outlet regulating disks are rotatably installed in the water inlet cavity and the water outlet cavity respectively, and a plurality of first water holes with different diameters are evenly arranged on the outside of the impeller cavity; An impeller adjustment module is installed inside the impeller cavity. The impeller adjustment module includes a back plate and blades. One side of the back plate is connected to the coupling assembly, and the other side of the back plate is evenly installed with a number of synchronously rotatable blades.

[0005] In a preferred embodiment, a water inlet pipe and a water outlet pipe are respectively fixed on both sides of the top of the pump body, the water inlet pipe is connected to the water inlet chamber, and the water outlet pipe is connected to the water outlet chamber. A first channel and a second channel are also provided inside the pump body, the water inlet chamber and the impeller chamber are connected through the first channel, and the water outlet chamber and the impeller chamber are connected through the second channel.

[0006] In a preferred solution, a second water through hole is opened on one side of the inlet and outlet regulating disks, and the second water through holes on the two inlet and outlet regulating disks are aligned with the water inlet pipe and the water outlet pipe respectively.

[0007] In a preferred embodiment, a rotary adjusting member is installed on one side of the middle of the inlet and outlet adjusting disks, a ratchet is provided on the inner side of the rotary adjusting member, and the ratchets in the two rotary adjusting members are arranged in opposite directions. A rotating shaft is rotatably connected between the two inlet and outlet adjusting disks, a first bevel gear is fixed to the middle of the rotating shaft, a second motor is fixed to the top of the pump body, a second bevel gear is fixed to the output end of the second motor, and the second bevel gear is meshed and connected with the first bevel gear; Rotating disks are installed at both ends of the rotating shaft, and ratchets are rotatably connected to the outer sides of the rotating disks. The ratchets arranged on the two rotating disks face in opposite directions, and an elastic sheet is installed below the ratchets and on the rotating disks.

[0008] In a preferred embodiment, a rotating shaft is fixed at one end of the blade and located inside the back plate, an extension rod is fixed on the outside of the rotating shaft, a rotating driving member is rotatably connected to the middle part of the back plate, a plurality of protruding connecting blocks are evenly arranged on the outside of the rotating driving member, a driving connecting rod is installed between the protruding connecting block and the extension rod, and both ends of the driving connecting rod are rotatably connected.

[0009] In a preferred embodiment, an external driving block is fixed at one end of the rotating driving member and on one side of the back plate, an adjustment groove is opened in the middle of the external driving block, a third motor is installed inside the pump body, an electric push rod is fixed at the output end of the third motor, an angle adjustment block is fixed at the output end of the electric push rod, and the angle adjustment block has the same shape as the adjustment groove opened in the external driving block.

[0010] In a preferred embodiment, rotating rings are provided on the outer sides of both sides of the inlet and outlet regulating disks, the rotating rings are located inside the water inlet cavity and the water outlet cavity, and the rotating rings are rotatably connected to the pump body.

[0011] In a preferred embodiment, a temperature detector, a pressure detector and an intelligent control module are provided inside the pump body.

[0012] In a preferred embodiment, a base is installed at the bottom of the first motor, the first motor is installed at one end of the base, and the pump body is installed at the other end of the base.

[0013] A control method for low cavitation hot water circulation, used for a hot water circulation pump as described in any one of the above, comprises the following steps: S1. Preparation before starting: Check whether the pump body and the first motor are firmly installed, and make sure that the base is not loose. Confirm that the water inlet and outlet pipes are correctly connected and leak-free. Check whether a small amount of sealing water is allowed to leak from the shaft seal, not exceeding 20 drops / minute to 25 drops / minute. Determine the impeller speed during startup. S2. Adjust the inlet and outlet flow rates. According to the impeller speed, control the rotation of the two inlet and outlet adjustment disks so that the first water holes of appropriate diameters are connected to the first channel and the second channel respectively, so as to control the flow rates and pressures of the water inlet and outlet chambers, and ensure that the second water holes on the inlet and outlet adjustment disks are aligned with the water inlet pipe and the water outlet pipe to optimize the water flow path; S3, blade angle adjustment, start the third motor, push the external drive block through the electric push rod, so that the rotating drive part inside the back plate drives the blade to rotate synchronously, and adjust the blade angle to optimize the fluid dynamics performance; S4, monitor temperature and pressure, use the temperature detector and pressure detector inside the pump body to monitor the temperature and pressure changes in the hot water circulation process in real time, and according to the monitoring data, the intelligent control module automatically adjusts the working state of the motor to avoid the occurrence of cavitation; S5. Shutdown operation: Before shutdown, gradually reduce the speed and power output of the hot water pump to avoid the water hammer effect caused by sudden shutdown, turn off the power supply, and disconnect the control system.

[0014] The technical effects achieved by the present invention are: The present invention can accurately control the water inlet flow rate by setting the water inlet and outlet regulating module, and can adjust the water inlet flow rate according to the rotation speed of the impeller, so as to ensure the stability of the pressure at the inlet of the pump body and avoid the formation of bubbles due to too low pressure, which helps to reduce the occurrence of cavitation and improve the service life of the pump. At the same time, the blades can also adjust the angle according to the change of the impeller rotation speed, so as to optimize the water flow path, reduce eddy currents and turbulence, and further reduce the possibility of bubble formation. The present invention can also adjust the water flow rate through the inlet and outlet water regulating module, and change it synchronously according to the change of the impeller speed, thereby reducing the pressure drop at the pump body outlet and reducing the impact force generated when the bubble bursts, thereby improving the anti-cavitation ability of the pump. In addition, the adjustable angle design of the blades enables the pump body to maintain the optimal impeller angle and speed under different working conditions, which not only improves the efficiency of the pump, but also enhances the pump's resistance to cavitation; The present invention can adapt to different water inlet and outlet volumes according to different impeller rotation speeds by precisely controlling the water inlet and outlet flow rates, thereby avoiding instability of the pump body caused by excessive or insufficient flow rates, such as pressure fluctuations, water flow oscillations, etc. This helps to maintain stable operation of the pump body and reduce failures caused by cavitation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a cross-sectional connection schematic diagram of the internal structure of the pump body of the present invention; Figure 3 It is a schematic diagram of the cross-sectional structure of the pump body of the present invention; Figure 4 It is a structural explosion diagram of the water inlet and outlet regulating module of the present invention; Figure 5 It is a schematic cross-sectional structure diagram of the inlet and outlet adjustment disk of the present invention; Figure 6 It is a partial structural schematic diagram of the inlet and outlet water regulating module of the present invention; Figure 7 It is a structural exploded diagram of the impeller adjustment module of the present invention; Figure 8 It is a schematic diagram of the connection structure between the blade and the driving connecting rod of the present invention; Fig. 9 is a schematic diagram of the internal cross-sectional structure of the back plate of the present invention; Fig.10 It is a schematic diagram of the connection between the ratchet and the rotary adjusting member of the present invention.

[0016] In the accompanying drawings, the components represented by the reference numerals are listed as follows: 1. The first motor; 2. The pump body; 3. The water inlet and outlet adjustment module; 4. The impeller adjustment module; 11. The coupling assembly; 12. The base; 21. The impeller chamber; 22. The water inlet chamber; 23. The water outlet chamber; 24. The water inlet pipe; 25. The water outlet pipe; 26. The first channel; 27. The second channel; 31. The inlet and outlet adjustment disks; 32. The rotating adjustment member; 33. The rotating ring; 34. The rotating shaft; 35. The first bevel gear; 36. The second bevel gear; 37. The rotating disk; 38. The pawl; 39. The second motor; 41. The back plate; 42. The blades; 43. The rotating shaft; 44. The extension rod; 45. The driving connecting rod; 46. The rotating driving member; 47. The protruding connecting block; 48. The external driving block; 49. The third motor; 50. The electric push rod; 51. The angle adjustment block. DETAILED DESCRIPTION

[0017] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0018] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0019] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. The phrase "in a preferred embodiment" that appears in different places in this specification does not refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0020] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0021] Example 1 Please see attached Figures 1 to 10 As shown, it is the first embodiment of the present invention, which provides a hot water circulation pump, including a first motor 1, a coupling assembly 11 and a pump body 2, the coupling assembly 11 is installed between the first motor 1 and the pump body 2, a base 12 is installed at the bottom of the first motor 1, the first motor 1 is installed at one end of the base 12, and the pump body 2 is installed at the other end of the base 12; A water inlet chamber 22 and a water outlet chamber 23 are respectively provided on both sides of the top of the pump body 2, and an impeller chamber 21 is provided inside the first motor 1 and below the water outlet chamber 23; The water inlet and outlet regulating module 3 is installed in the water inlet chamber 22 and the water outlet chamber 23. The water inlet and outlet regulating module 3 includes two inlet and outlet regulating disks 31. The two inlet and outlet regulating disks 31 are rotatably installed in the water inlet chamber 22 and the water outlet chamber 23 respectively. A plurality of first water holes with different diameters are evenly arranged on the outer side of the impeller chamber 21; The impeller adjustment module 4 is installed inside the impeller cavity 21. The impeller adjustment module 4 includes a back plate 41 and blades 42. One side of the back plate 41 is connected to the coupling assembly 11, and the other side of the back plate 41 is evenly installed with a plurality of blades 42 that can rotate synchronously; In the above, when in use, the speed of the impeller is determined, and the impeller adjustment module 4 is started according to the impeller speed to change the angle of the blade 42, so that the impeller with the current blade 42 angle is more suitable for the current speed, and the problem of vortex generation or increased resistance caused by the change in speed, which is caused by the blade 42 being unable to adapt to a higher or lower speed, is reduced. Changing the angle of the blade 42 while changing the speed can adapt to the characteristics of the fluid pressure and flow consumption changed by the increase in speed, thereby reducing the generation of vortices and backflow in the pump, thereby reducing the generation of bubbles and achieving the effect of anti-cavitation. The inlet and outlet water adjustment module 3 set can accurately control the water flow, adjust the diameter of the corresponding inlet and outlet according to the change in the speed of the impeller, balance the internal and external pressures, and reduce the inlet resistance, thereby reducing the generation of bubbles and reducing the risk of cavitation.

[0022] In a preferred embodiment, please refer to Figure 2 and Figure 3 A water inlet pipe 24 and a water outlet pipe 25 are fixed on both sides of the top of the pump body 2, respectively. The water inlet pipe 24 is connected to the water inlet chamber 22, and the water outlet pipe 25 is connected to the water outlet chamber 23. A first channel 26 and a second channel 27 are also provided inside the pump body 2. The water inlet chamber 22 is connected to the impeller chamber 21 through the first channel 26, and the water outlet chamber 23 is connected to the impeller chamber 21 through the second channel 27.

[0023] A second water through hole is opened on one side of the inlet and outlet regulating disk 31 , and the second water through holes on the two inlet and outlet regulating disks 31 are aligned with the water inlet pipe 24 and the water outlet pipe 25 respectively.

[0024] In the above, by starting the impeller to rotate, water can be sucked into the water inlet chamber 22 from the water inlet pipe 24, and flow into the impeller chamber 21 through the first channel 26, and then flow into the water outlet chamber 23 from the second channel 27 and finally be drawn out from the water outlet pipe 25. Inlet and outlet regulating disks 31 will be installed in the water inlet chamber 22 and the water outlet chamber 23. During specific use, the rotation of the inlet and outlet regulating disks 31 will be controlled according to the rotation speed of the impeller to change the diameter of the first water hole aligned with the first channel 26 and the second channel 27, so as to control the inlet and outlet water flow and pressure.

[0025] Next, please refer to Figure 4 , Figure 5 and Figure 6 A rotary adjusting member 32 is installed on one side of the middle of the inlet and outlet adjusting disk 31, and a ratchet is provided on the inner side of the rotary adjusting member 32. The ratchets in the two rotary adjusting members 32 are arranged in opposite directions. A rotating shaft 34 is rotatably connected between the two inlet and outlet adjusting disks 31, and a first bevel gear 35 is fixed to the middle of the rotating shaft 34. A second motor 39 is fixed to the top of the pump body 2, and a second bevel gear 36 is fixed to the output end of the second motor 39, and the second bevel gear 36 is meshed and connected with the first bevel gear 35; Rotating disks 37 are installed at both ends of the rotating shaft 34. The outer sides of the rotating disks 37 are rotatably connected with pawls 38. The pawls 38 arranged on the two rotating disks 37 face opposite directions. An elastic sheet is installed below the pawls 38 and on the rotating disks 37.

[0026] In the above, specifically when controlling the rotation of the inlet and outlet adjustment disks 31, the second motor 39 installed above the pump body 2 drives the second bevel gear 36 to rotate, and the second bevel gear 36 drives the first bevel gear 35 to rotate under the action of meshing, thereby controlling the rotation of the rotating shaft 34, and at the same time drives the rotating disks 37 connected at both ends to rotate together, and drives the pawl 38 connected to the rotating disk 37 to move during rotation, and because the ratchets arranged on the two rotating adjustment members 32 are in opposite directions, the pawls 38 arranged on the two rotating disks 37 are also in opposite directions, when the rotating shaft 34 rotates to one side, only the rotating adjustment member 32 on one side will be pushed by the pawl 38 to rotate, while the other side will not, and when the opposite rotating shaft 34 rotates in the opposite direction, the rotating adjustment member 32 on the other side is pushed to rotate, thereby being able to control the two inlet and outlet adjustment disks 31 to rotate, completing the switching of the first water through hole.

[0027] Example 2 Please see attached Figures 1 to 10As shown, it is the second embodiment of the present invention, which provides a hot water circulation pump, wherein a rotating shaft 43 is fixed at one end of the blade 42 and located inside the back plate 41, an extension rod 44 is fixed to the outside of the rotating shaft 43, a rotating driving member 46 is rotatably connected to the middle part of the back plate 41, and a plurality of protruding connecting blocks 47 are evenly arranged on the outside of the rotating driving member 46, a driving connecting rod 45 is installed between the protruding connecting block 47 and the extension rod 44, and both ends of the driving connecting rod 45 are rotatably connected.

[0028] In the above, when it is necessary to control the angle deflection of the blade 42, the rotation of the rotating driving member 46 is controlled. When the rotating driving member 46 rotates, the protruding connecting block 47 connected to its outer side will be deflected. When the protruding connecting block 47 is deflected, the driving connecting rod 45 will be moved together, and the extension rod 44 will be driven to swing along the rotating shaft 43, thereby driving the rotating shaft 43 and the blade 42 to produce an angle deflection, thereby achieving the purpose of adjusting the angle of the blade 42.

[0029] Secondly, please also refer to Figure 2 , Figure 7 , Figure 8 and Fig. 9 An external driving block 48 is fixed to one end of the rotating driving member 46 and located on one side of the back plate 41, and an adjustment groove is opened in the middle of the external driving block 48. A third motor 49 is installed inside the pump body 2, and an electric push rod 50 is fixed to the output end of the third motor 49. An angle adjustment block 51 is fixed to the output end of the electric push rod 50, and the angle adjustment block 51 has the same shape as the adjustment groove opened in the external driving block 48.

[0030] In the above, when it is necessary to drive the rotary drive member 46 to rotate, the electric push rod 50 installed in the pump body 2 pushes the angle adjustment block 51 to be inserted into the adjustment slot of the external drive block 48, and the third motor 49 is started to drive the electric push rod 50 and the angle adjustment block 51 to rotate together, and at the same time drive the external drive block 48 connected to the angle adjustment block 51 to rotate, thereby driving the rotary drive member 46 to rotate and transmitting the blade 42 to cause an angle deviation, thereby completing the angle adjustment of the blade 42.

[0031] Secondly, please refer to Figure 2 and Figure 4 A rotating ring 33 is provided on the outer sides of both sides of the inlet and outlet regulating disks 31 . The rotating ring 33 is located inside the water inlet chamber 22 and the water outlet chamber 23 , and the rotating ring 33 is rotatably connected to the pump body 2 .

[0032] In the above, the rotating ring 33 is used to provide friction, so that the inlet and outlet adjustment disks 31 can maintain their original state when they are not actively controlled to rotate, and will not move due to the influence of water flow.

[0033] Furthermore, a temperature detector, a pressure detector and an intelligent control module are provided inside the pump body 2; The temperature detector and pressure detector arranged inside the pump body 2 are used to monitor the working status inside the pump body in real time, including water temperature and water pressure. The monitoring of these key parameters helps to detect abnormal conditions in time, such as overheating or overpressure, so as to take preventive measures to avoid equipment damage and potential safety hazards. The intelligent control module can automatically adjust the operating parameters of the pump according to the real-time temperature and pressure data to ensure that the pump operates under the best working conditions. This adaptive adjustment not only improves the efficiency of the pump, but also extends the service life of the equipment.

[0034] Example 3 This embodiment provides a control method for low cavitation hot water circulation, which is used for a hot water circulation pump of Embodiment 1 and Embodiment 2, and is characterized by comprising the following steps: S1. Preparation before starting: check whether the pump body 2 and the first motor 1 are firmly installed, and make sure that the base 12 is not loose. Confirm that the water inlet pipe 24 and the water outlet pipe 25 are correctly connected and leak-free. Check whether a small amount of sealing water is allowed to leak from the shaft seal, not exceeding 20 drops / minute to 25 drops / minute. Determine the impeller speed during starting. S2. Adjust the inlet and outlet flow rates. According to the impeller speed, control the rotation of the two inlet and outlet adjustment disks 31 so that the first water holes of appropriate diameters are connected to the first channel 26 and the second channel 27 respectively, so as to control the flow rates and pressures of the water inlet chamber 22 and the water outlet chamber 23, and ensure that the second water holes on the inlet and outlet adjustment disks are aligned with the water inlet pipe 24 and the water outlet pipe 25 to optimize the water flow path; S3, blade angle adjustment, start the third motor 49, push the external drive block 48 through the electric push rod 50, so that the rotating drive member 46 inside the back plate 41 drives the blade 42 to rotate synchronously, and adjust the blade angle to optimize the fluid dynamics performance; S4, monitoring temperature and pressure, using the temperature detector and pressure detector inside the pump body 2 to monitor the temperature and pressure changes in the hot water circulation process in real time, and according to the monitoring data, the intelligent control module automatically adjusts the working state of the motor to avoid the occurrence of cavitation; S5. Shutdown operation: Before shutdown, gradually reduce the speed and power output of the hot water pump to avoid the water hammer effect caused by sudden shutdown, turn off the power supply, and disconnect the control system.

[0035] The working principle of the present invention is as follows: before starting, the device is checked in all directions. After confirmation, the inlet and outlet water regulating module 3 is adjusted according to the speed of the impeller after startup. When adjusting the inlet and outlet water regulating module 3, the second bevel gear 36 is driven to rotate by the second motor 39, and the engagement drives the rotating shaft 34 to rotate in the forward or reverse direction, and the two inlet and outlet regulating disks 31 connected by the ratchet structure are respectively controlled to rotate, and the appropriate first water hole is adjusted and aligned with the first channel 26 and the second channel 27 respectively. Then, according to the speed of the impeller, the electric push rod 50 is controlled to push the angle adjustment block 51, so that the angle adjustment block 51 is inserted into the adjustment slot of the external drive block 48, and the angle adjustment block 51 is driven to rotate by the third motor 49, and the rotation drive member 46 is driven to rotate, and after transmission, the blade 42 is caused to produce an angle offset, and the blade is adjusted. After the angle 42 is adjusted to adapt to the impeller speed, it stops, the device is started, the impeller rotates, a vacuum is generated, and the liquid is drawn into the water inlet chamber 22. The adjusted inlet and outlet water regulating module 3 can accurately control the water flow, and adjust the diameter of the corresponding inlet and outlet according to the change in the speed of the impeller, so as to balance the internal and external pressures and reduce the inlet resistance, thereby reducing the generation of bubbles and reducing the risk of cavitation. At the same time, the adjusted blades 42 are more suitable for the current speed, reducing the problem of vortex generation or increased resistance caused by the change in speed and the inability of the blades 42 to adapt to higher or lower speeds. Changing the angle of the blades 42 while changing the speed can adapt to the characteristics of the fluid pressure and flow consumption changed by the increased speed, thereby reducing the generation of vortices and backflow in the pump, thereby reducing the generation of bubbles and achieving the effect of anti-cavitation.

[0036] The above is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention shall be implemented according to the conventional means in the art unless otherwise specified and limited.

Claims

1. A hot water circulation pump, characterized in that: It comprises a first motor (1), a coupling assembly (11) and a pump body (2), wherein the coupling assembly (11) is installed between the first motor (1) and the pump body (2); A water inlet chamber (22) and a water outlet chamber (23) are respectively provided on both sides of the top of the pump body (2), and an impeller chamber (21) is provided inside the first motor (1) and below the water outlet chamber (23); An inlet and outlet water regulating module (3), the inlet and outlet water regulating module (3) being installed in the water inlet chamber (22) and the water outlet chamber (23), the inlet and outlet water regulating module (3) comprising two inlet and outlet regulating disks (31), the two inlet and outlet regulating disks (31) being rotatably installed inside the water inlet chamber (22) and the water outlet chamber (23), respectively, and a plurality of first water holes of different diameters being evenly arranged on the outer side of the impeller chamber (21); An impeller adjustment module (4), the impeller adjustment module (4) being installed inside the impeller cavity (21), the impeller adjustment module (4) comprising a back plate (41) and blades (42), one side of the back plate (41) being connected to the coupling assembly (11), and the other side of the back plate (41) being evenly mounted with a plurality of blades (42) that can rotate synchronously; A rotary adjusting member (32) is installed on one side of the middle of the inlet and outlet adjusting disk (31), a ratchet is provided on the inner side of the rotary adjusting member (32), and the ratchet teeth in the two rotary adjusting members (32) are arranged in opposite directions. A rotating shaft (34) is rotatably connected between the two inlet and outlet adjusting disks (31), a first bevel gear (35) is fixed to the middle of the rotating shaft (34), a second motor (39) is fixed to the top of the pump body (2), a second bevel gear (36) is fixed to the output end of the second motor (39), and the second bevel gear (36) is meshingly connected with the first bevel gear (35); Rotating disks (37) are mounted on both ends of the rotating shaft (34); ratchets (38) are rotatably connected to the outer sides of the rotating disks (37); the ratchets (38) arranged on the two rotating disks (37) face in opposite directions; and an elastic sheet is mounted below the ratchets (38) and on the rotating disks (37).

2. A hot water circulation pump according to claim 1, characterized in that: A water inlet pipe (24) and a water outlet pipe (25) are respectively fixed to both sides of the top of the pump body (2); the water inlet pipe (24) is in communication with the water inlet chamber (22); the water outlet pipe (25) is in communication with the water outlet chamber (23); a first channel (26) and a second channel (27) are further provided inside the pump body (2); the water inlet chamber (22) is in communication with the impeller chamber (21) via the first channel (26); the water outlet chamber (23) is in communication with the impeller chamber (21) via the second channel (27).

3. A hot water circulation pump according to claim 2, characterized in that: A second water through hole is provided on one side of the inlet and outlet regulating disk (31), and the second water through holes on the two inlet and outlet regulating disks (31) are aligned with the water inlet pipe (24) and the water outlet pipe (25), respectively.

4. A hot water circulation pump according to claim 1, characterized in that: A rotating shaft (43) is fixed at one end of the blade (42) and is located inside the back plate (41); an extension rod (44) is fixed outside the rotating shaft (43); a rotating driving member (46) is rotatably connected to the middle of the back plate (41); a plurality of protruding connecting blocks (47) are evenly arranged on the outside of the rotating driving member (46); a driving connecting rod (45) is installed between the protruding connecting block (47) and the extension rod (44); and both ends of the driving connecting rod (45) are rotatably connected.

5. A hot water circulation pump according to claim 4, characterized in that: An external drive block (48) is fixed at one end of the rotary drive member (46) and located on one side of the back plate (41); an adjustment slot is provided in the middle of the external drive block (48); a third motor (49) is installed inside the pump body (2); an electric push rod (50) is fixed at the output end of the third motor (49); an angle adjustment block (51) is fixed at the output end of the electric push rod (50); the angle adjustment block (51) has the same shape as the adjustment slot provided in the external drive block (48).

6. A hot water circulation pump according to claim 1, characterized in that: Rotating rings (33) are provided on the outer sides of both sides of the inlet and outlet adjustment disks (31); the rotating rings (33) are located inside the water inlet chamber (22) and the water outlet chamber (23); and the rotating rings (33) are rotatably connected to the pump body (2).

7. A hot water circulation pump according to claim 1, characterized in that: A temperature detector, a pressure detector and an intelligent control module are arranged inside the pump body (2).

8. A hot water circulation pump according to claim 1, characterized in that: A base (12) is installed at the bottom of the first motor (1); the first motor (1) is installed at one end of the base (12), and the pump body (2) is installed at the other end of the base (12).

9. A control method for low cavitation hot water circulation, used for a hot water circulation pump according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Preparation before starting: check whether the pump body (2) and the first motor (1) are firmly installed, and ensure that the base (12) is not loose. Confirm that the water inlet pipe (24) and the water outlet pipe (25) are correctly connected and leak-free. Check whether a small amount of sealing water is allowed to leak from the shaft seal, not exceeding 20 drops / minute to 25 drops / minute. Determine the impeller speed during starting; S2, adjusting the inlet and outlet flow rates, controlling the rotation of the two inlet and outlet regulating disks (31) according to the impeller speed, so that the first water holes of appropriate diameters are connected to the first channel (26) and the second channel (27) respectively, so as to control the flow rates and pressures of the water inlet chamber (22) and the water outlet chamber (23), and ensure that the second water holes on the inlet and outlet regulating disks are aligned with the water inlet pipe (24) and the water outlet pipe (25), so as to optimize the water flow path; S3, blade angle adjustment, start the third motor (49), push the external drive block (48) through the electric push rod (50), so that the rotating drive member (46) inside the back plate (41) drives the blade (42) to rotate synchronously, and adjust the blade angle to optimize the fluid dynamics performance; S4, monitoring temperature and pressure, using the temperature detector and pressure detector inside the pump body (2) to monitor the temperature and pressure changes in the hot water circulation process in real time, and based on the monitoring data, the intelligent control module automatically adjusts the working state of the motor to avoid the occurrence of cavitation; S5. Shutdown operation: Before shutdown, gradually reduce the speed and power output of the hot water pump to avoid the water hammer effect caused by sudden shutdown, turn off the power supply, and disconnect the control system.

Images