Axial flow pump with protection function

Abstract

The invention relates to the technical field of axial flow pumps, and particularly discloses an axial flow pump with a protection function, which comprises a pump shell, an impeller arranged in the pump shell and a driving shaft for driving the impeller to rotate, a connecting assembly is arranged between the impeller and the driving shaft, and the connecting assembly comprises an input piece, an output piece, a transmission piece, a first meshing piece and a second meshing piece. The output part is rotationally arranged on the input part, an input shaft is arranged on the input part and fixedly connected with one end of the driving shaft, an output shaft is arranged on the output part and fixedly connected with the impeller, and the transmission part is arranged between the input part and the output part. The device has the effect that the driving shaft and the impeller bearing are protected against sudden shutdown and fluid backflow inertial impact damage.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of axial flow pumps, in particular to an axial flow pump with a protection function. BACKGROUND

[0002] At present, axial flow pumps are widely used in large water body transportation scenes such as mountain flood drainage, reservoir flood discharge and irrigation water diversion due to their large flow and low lift characteristics. In particular, in the mountain or reservoir environment where water level changes dramatically and flow velocity changes frequently, axial flow pumps bear the key tasks of hydraulic regulation and emergency drainage. In the actual application process, due to the uncertainty of the natural environment and the increase in the complexity of the pump station system, such as sudden power failure of the power supply system, control system failure or damage to the pump house structure, etc. In such emergencies, once the axial flow pump loses driving force during operation or the pump house appears abnormally, it will inevitably cause the downstream water body to flow back into the pump body due to gravity or inertia, forming a short-time high-intensity reverse water flow impact, which will cause great threat to the core components of the pump set.

[0003] In terms of preventing water backflow from damaging the axial flow pump, the existing technology mainly focuses on pipeline check, rotating part locking and electric control protection, for example, a common way is to set a check valve structure in the axial flow pump outlet pipeline, when the water flow direction is reversed, the check valve can be automatically closed relying on the water flow pressure, effectively preventing the water backflow into the pump body. In addition, in some large pump station systems, mechanical brakes or hydraulic locking mechanisms are also used to forcibly lock the motor or impeller shaft, which can inhibit the movement of the pump shaft for a short time after the electric control signal is triggered, so as to reduce the structural damage caused by reverse rotation. Some systems also introduce torque protectors, shaft breakage safety devices and other force limiting elements, which can preferentially disconnect the connecting parts when subjected to overload impact, thereby protecting the integrity of the main pump shaft and motor. These existing technologies have a certain effect in preventing reverse water impact damage to a certain extent, and have played a positive protection role in the safe operation of the pump station.

[0004] Although the above-mentioned existing technology has a certain practicability in protecting the axial flow pump from reverse impact, there are still some problems in actual working conditions. First of all, the pipeline check device generally has a lagging action problem and cannot respond quickly within the first few seconds of reverse water flow, which can easily cause some high-energy water flow to enter the pump body and impact the impeller. Secondly, the mechanical brake and hydraulic locking mechanism generally rely on external electric control signals, which are difficult to play the expected effect when the power is off or the control fails. In addition, the torque protector and shaft breakage safety device are passive protection measures that only work after overload occurs, and cannot achieve preventive control of reverse rotation. Moreover, after triggering, it will cause damage to the components and system shutdown, affecting the operation and maintenance efficiency. SUMMARY

[0005] The application provides a shaft flow pump with a protection function, which can automatically realize dynamic motion separation and multi-stage slow release of reverse water flow impact, effectively protecting the driving shaft and impeller from damage caused by sudden stop and fluid backflow inertia impact.

[0006] The application provides a shaft flow pump with a protection function, which adopts the following technical scheme: The application provides a shaft flow pump with a protection function, which adopts the following technical scheme: The application provides a shaft flow pump with a protection function, which adopts the following technical scheme: When the input part rotates in the first rotation direction, the output part transmits torque by meshing with the input part through the second meshing part, and the first meshing part is in a free rotation state; when the input part rotates in the second direction, the second meshing part is in a free rotation state, and the output part transmits torque by meshing with the input part through the first meshing part. When the rotation speed of the output part exceeds that of the input part, both the first meshing mechanism and the second meshing mechanism are in a free rotation state.

[0007] By adopting the above technical scheme, the first meshing part and the second meshing part correspond to the rotation of the input part in two directions, respectively, so that torque transmission can be realized through the corresponding meshing channels according to the rotation direction when the pump set is normally working, the driving force can be obtained by the impeller in different operating directions, the water flow scheduling demand under complex working conditions is met, and the system adaptability and control accuracy are improved; when sudden power failure occurs in the pump body, the driving shaft stops, or the control system fails, if reverse impact is formed due to water level difference or inertial flow of downstream water body, the impeller may be forced to rotate in reverse; at this time, the rotation speed of the output part is greater than that of the input part, the first meshing part and the second meshing part can automatically release the meshing state and interrupt the torque transmission path, an active anti-impact protection mechanism is constructed, reverse torque is effectively prevented from being transmitted to the motor or the driving shaft, and active mechanical disconnection protection is realized; in addition, the connecting assembly adopts a limited direction meshing mechanism composed of pure mechanical structures, which completely depends on the relative motion state between the pump shaft and the impeller for torque engagement and disengagement, does not need to rely on electrical control signals, sensors or control units, is especially suitable for automatically triggering the protection function under power failure, communication failure or extreme weather, and has high reliability and practicality.

[0008] Optionally, the input member is disc-shaped, one side of the input member is fixedly provided with an input shaft, the input shaft is fixedly connected with one end of the driving shaft, a mounting groove is formed on the side of the input member away from the input shaft, the transmission member is rotatably arranged in the mounting groove, and the transmission member is in transmission connection with the output member.

[0009] By adopting the above technical scheme, the input member is disc-shaped, has the input shaft and the mounting groove, the transmission member is arranged in the mounting groove and is in transmission connection with the output member, the mounting groove is arranged to embed the transmission member, the stability and the axial concentricity of the overall transmission assembly are improved, and more reliable installation space is provided for the subsequent meshing members, and the system operation stability and the structural reliability are enhanced.

[0010] Optionally, the transmission member is disc-shaped, a first wedge-shaped groove and a second wedge-shaped groove are formed through the transmission member, the first wedge-shaped groove and the second wedge-shaped groove are in communication, and the communication part of the first wedge-shaped groove and the second wedge-shaped groove is arranged as a plug-in cavity; the first meshing member includes a first roller, a first abutting column and a first spring, a first containing groove is formed in the inner wall of the first wedge-shaped groove, the first abutting column is slidably arranged in the first containing groove, the first spring is arranged in the first containing groove, one end of the first spring is connected with one end of the first abutting column, the other end of the first spring is connected with the inner wall of the first containing groove, and the end of the first abutting column away from the first spring is in sliding abutment with the first roller; the second meshing member includes a second roller, a second abutting column and a second spring, the second meshing member and the first meshing member are arranged in the same manner, the second wedge-shaped groove and the first wedge-shaped groove are arranged in the same manner, the first wedge-shaped groove and the second wedge-shaped groove are symmetrically arranged with the center line of the plug-in cavity as the center, and the second meshing member is arranged in the second wedge-shaped groove.

[0011] By adopting the technical scheme, the first wedge-shaped groove and the second wedge-shaped groove are arranged on the transmission member, and the meshing assembly composed of the roller, the abutting column and the spring is arranged in each wedge-shaped groove, a mirror image symmetrical arrangement structure of a set of forward rotation meshing mechanisms and a set of reverse rotation meshing mechanisms is formed, the first meshing member and the second meshing member are respectively engaged in meshing transmission when the axial flow pump normally works and when abnormal backflow occurs, the system can automatically switch according to the rotation direction of the input member and the rotating speed of the output member, without the need of electric control or additional switching signals, and a real structure self-adaptive transmission mechanism is realized, when the impeller is driven to rotate by the reverse water flow, the first meshing member and the second meshing member are in an idle state because the roller cannot form effective engagement with the transmission member, so that the reverse torque transmission link is interrupted, the high-strength water backflow is effectively prevented from conducting destructive kinetic energy to the driving motor and the driving shaft, and the core protection effect of overspeed decoupling and reverse impact prevention is achieved; in addition, the first wedge-shaped groove and the second wedge-shaped groove are symmetrically arranged about the plug-in cavity, the structure is balanced, the axial eccentricity can be effectively reduced, the torque fluctuation can be reduced, the system operation is more stable, and the service life of the connecting assembly and the pump shaft system is prolonged.

[0012] Optionally, the output member includes an output shaft and a fork part, one end of the output shaft is rotationally connected with the transmission member, one end of the fork part is fixedly arranged on the output shaft, and the end of the fork part away from the output shaft is plug-in matched with the plug-in cavity, one side of the fork part is movably abutted with the first roller, the other side of the fork part is movably abutted with the second roller, the fork part is provided with two groups, the two groups of fork parts are circumferentially distributed on the output shaft, and the impeller is fixedly arranged on the end of the output shaft away from the input member.

[0013] By adopting the technical scheme, the movable abutment form of the fork and the roller provides a flexible meshing structure, and the instantaneous impact force is reduced, and the circumferential arrangement of the multiple groups of forks enhances the torque bearing capacity and the rotating stability of the system; the output shaft and the impeller are directly connected, the torque transmission efficiency is improved, and the damage of the pump shaft caused by abnormal reverse rotation is prevented.

[0014] Optionally, it further comprises a slow-release assembly, the slow-release assembly comprises a shunt pipe and a blocking plate, the shunt pipe is arranged on the pump shell, one end of the shunt pipe is communicated with one end close to the water outlet end of the pump shell, the other end of the shunt pipe is fixedly connected with the outer wall close to the water inlet end of the pump shell, a piston block is slidably arranged in the shunt pipe, the piston block divides the shunt pipe into two independent cavities, the two independent cavities are respectively arranged as a shunt cavity and a piston cavity, an overflow pipe is arranged on the shunt pipe, one end of the overflow pipe is communicated with the shunt cavity, the other end of the overflow pipe is communicated with the pump shell, the piston block partially blocks one end of the overflow pipe close to the shunt pipe, the blocking plate is rotationally arranged in the shunt pipe, and the blocking plate is arranged inclined relative to the inner wall of the shunt pipe, and the blocking plate is located at one end of the shunt pipe communicated with the pump shell.

[0015] By adopting the above technical scheme, the reverse high-pressure water flow generated by the axial flow pump in the sudden failure working condition can be coped with by using the arranged shunt pipe, piston block and blocking plate. Without external electric control or active intervention, the structure can actively shunt and slow release the reverse impact kinetic energy of the water body. When the reverse water flow impacts the pump body, the shunt pipe guides part of the water body at the water outlet end of the pump shell into the shunt pipe to form an alternative flow path, effectively dredges the instantaneous reverse water pressure, and reduces the direct impact strength on the impeller. At the same time, the piston block slides in the shunt pipe, and the blocking plate is arranged inclined, so that the water body forms flow damping in the shunt path, thereby realizing step-by-step release and buffer transition of the water flow speed, and improving the overall impact resistance of the system. In addition, the inclined arrangement of the blocking plate forms a gradual throttling opening, which can form a local blocking and energy dissipation area in the initial stage of the reverse high pressure, avoid the local water hammer concentration effect caused by the high-speed backflow of the water flow, and prevent the severe mechanical impact on the pump body structure. Once the water flow enters the shunt pipe, the blocking plate can prevent the backflow of the water body, and provides a reliable foundation for the subsequent magnetic block to slow down and consume energy of the impeller.

[0016] Optionally, the slow-release assembly further comprises a barrier, the pump shell is internally provided with a support frame, the barrier is arranged on the support frame, the barrier divides the pump shell into two chambers, and the two chambers are arranged as a first chamber and a second chamber respectively, the first chamber is in communication with the water outlet end of the pump shell, one end of the shunt pipe is in communication with the first chamber, the barrier is located in the first chamber, and the impeller is arranged in the second chamber.

[0017] By adopting the technical scheme, the barrier is designed in a conical structure, the outlet end has a smaller inner diameter than the injection end, a smooth channel is formed when water flows forward, when the water flow is reversed, the backwater pressure is concentrated on the outlet end with a smaller inner diameter, and the outlet end is shrunk to the center of the lumen, thereby achieving self-closing, effectively preventing the reverse water from entering the chamber where the impeller is located, and achieving passive and rapid response anti-backflow; at the same time, the elastic deformation of the barrier not only provides a closing function, but also forms a flexible buffer zone during the impact of the reverse water pressure, absorbs part of the water energy, and reduces the risk of structural damage to the impeller, bearing and other key components caused by instantaneous impact, compared with the traditional check valve or electric control protection mechanism, the structure can produce rapid response and self-closing effect at the initial stage of the reverse water flow, effectively making up for the defects of reaction lag and dependence on signal triggering of the traditional scheme, and further enhancing the safety redundancy design of the whole system; in addition, the whole closing process is completed based on the cooperation of water pressure and material elasticity, without external power source or control signal, and is particularly suitable for passive adaptive protection requirements in extreme situations such as sudden power failure of the pump station, and significantly enhances the anti-attack ability of the system.

[0018] Optionally, the slow-release assembly further comprises a magnetic block and an elastic telescopic rod, the magnetic block is slidingly arranged in the piston chamber, the piston chamber is filled with hydraulic oil, the magnetic block is located at one end of the shunt pipe away from the shunt chamber, the elastic telescopic rod is arranged in the piston chamber, one end of the elastic telescopic rod is connected with the magnetic block, and the other end of the elastic telescopic rod is connected with the inner wall of the shunt pipe.

[0019] By adopting the technical scheme, under the strong impact of the reverse water flow, the piston block slides along the shunt pipe, pushes the magnetic block to be close to the pump shell side, and the movement of the magnetic block is realized, and the impeller is made of metal conductor material (such as alloy steel), when the impeller moves in the magnetic field, the conductor cuts the magnetic induction lines to generate induced current, the induced current is subjected to Ampere force in the magnetic field, the generated force is opposite to the movement direction of the impeller, thereby a damping force is generated, the reverse rotation speed of the impeller is effectively slowed down, the inertia impact of the impeller and the driving shaft under the sudden reverse rotation condition is significantly reduced, the damage of the mechanical parts is effectively prevented, and the reliability and safety of the pump set are improved; the elastic telescopic rod is used for resetting the magnetic block, so that the magnetic block does not interfere with the normal operation of the impeller in the normal forward rotation state, the stability and sensitivity of the slow-release assembly are considered, and the passive automatic damping protection function can be realized without relying on external electric control signals, and the self-protection ability of the pump set under the condition of electric control failure or power failure is enhanced.

[0020] Optionally, a limiting block is fixed on the inner wall of the shunt chamber, the limiting block is located on the side of the piston block close to the shunt chamber, and the piston block abuts against the limiting block.

[0021] By adopting the technical scheme, the limiting block and the piston block are arranged in the shunt chamber to form mechanical limiting cooperation, the sliding range of the piston block in the shunt pipe is effectively limited, the excessive displacement of the piston block caused by hydraulic pressure or magnetic driving is prevented, the piston block is prevented from completely blocking the overflow pipe, so that the water in the shunt pipe cannot be effectively discharged, and then the reverse water flow slow-release capability of the entire axial flow pump system under extreme working conditions is affected.

[0022] In summary, the present application has at least one of the following beneficial technical effects: 1. The first engaging member and the second engaging member can automatically release the engaged state, interrupt the torque transmission path, and build an active anti-rebound protection mechanism, effectively preventing the reverse torque from being transmitted to the motor or the driving shaft, and realizing active mechanical disconnection protection; in addition, the connecting assembly adopts a pure mechanical structure directional engagement mechanism, which completely relies on the relative movement state between the pump shaft and the impeller for torque engagement and disengagement, does not need to rely on electric control signals, sensors or control units, and is particularly suitable for automatically triggering the protection function under power failure, communication failure or extreme weather, and has high reliability and practicality; 2. The use of a diversion pipe, a piston block, and a blocking plate can cope with the reverse high-pressure water flow generated by the axial flow pump in the sudden failure condition. This structure can actively divert and release the reverse impact kinetic energy of the water body without external electrical control or active intervention. The combination of the piston block and the blocking plate can form flow damping in the diversion path, thereby achieving step-by-step release and buffer transition of water flow speed, improving the overall impact resistance of the system. In addition, the reverse water flow pushes the magnetic block closer to the pump shell side, achieving the movement of the magnetic block, effectively slowing down the reverse rotation speed of the impeller using electromagnetic damping effect, significantly reducing the inertial impact of the impeller and drive shaft in the sudden reverse condition, effectively preventing damage to mechanical components, improving the reliability and safety of the pump set, and enhancing the self-protection ability of the pump set in the case of electrical control failure or power failure. 3. The self-sealing arrangement of the barrier effectively prevents the reverse water body from entering the chamber where the impeller is located, achieving passive and rapid response anti-backflow. The elastic deformation of the barrier not only provides sealing function, but also forms a flexible buffer zone during the reverse water pressure impact, absorbing part of the water energy and reducing the risk of structural damage to the impeller, bearings, and other key components caused by instantaneous impact. Compared with traditional check valves or electrical control protection mechanisms, this structure can produce rapid response and self-closing effect at the initial stage of reverse water flow, effectively making up for the defects of traditional solutions such as reaction lag and dependence on signal triggering, and further enhancing the overall safety redundancy design of the system. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is the overall structure schematic diagram of the axial flow pump in the embodiment of the present application.

[0024] Figure 2 is the cross-sectional structure schematic diagram of the axial flow pump in the embodiment of the present application along Figure 1 the B-B line.

[0025] Figure 3 is the partial cross-sectional structure schematic diagram of the axial flow pump in the embodiment of the present application.

[0026] Figure 4 is the exploded schematic diagram of the connecting assembly in the embodiment of the present application.

[0027] Figure 5 is the overall structure schematic diagram of the connecting assembly in the embodiment of the present application.

[0028] : 1, pump shell; 11, support frame; 12, first chamber; 13, second chamber; 2, impeller; 3, drive shaft; 4, connecting assembly; 41, input piece; 411, input shaft; 412, mounting groove; 42, output piece; 421, output shaft; 422, yoke part; 43, transmission piece; 431, first wedge-shaped groove; 432, second wedge-shaped groove; 433, plug-in cavity; 434, first containing groove; 44, first engagement piece; 441, first roller; 442, first abutment column; 443, first spring; 45, second engagement piece; 451, second roller; 452, second abutment column; 453, second spring; 5, slow-release assembly; 51, shunt pipe; 511, shunt chamber; 512, piston chamber; 513, limiting block; 52, plugging plate; 53, piston block; 54, overflow pipe; 55, barrier piece; 56, magnetic block; 57, elastic telescopic rod; 6, drive motor. DETAILED DESCRIPTION

[0029] The above description is made in conjunction with the accompanying drawings. Figures 1-5 The application is further described in detail.

[0030] The application discloses an axial flow pump with a protection function.

[0031] Referring to Figure 1 and Figure 2 , the axial flow pump with the protection function comprises a pump shell 1, a drive motor 6, a drive shaft 3, an impeller 2, a connecting assembly 4 and a slow-release assembly 5. The drive motor 6 is installed on the pump shell 1, the drive shaft 3 is rotatably arranged on the pump shell 1, one end of the drive shaft 3 is fixedly connected with an output end of the drive motor 6, the impeller 2 is installed on the end of the drive shaft 3 away from the drive motor 6, the connecting assembly 4 is installed between the impeller 2 and the drive shaft 3, and the slow-release assembly 5 is installed on the pump shell 1. The pump shell 1 serves as a mounting base, the drive motor 6 serves as a power source of the axial flow pump, the drive shaft 3 is used for transmitting the torque of the drive motor 6, the impeller 2 can convert the torque transmitted by the drive shaft 3 into kinetic energy and pressure energy of fluid, the connecting assembly 4 can realize dynamic separation of movement between the impeller 2 and the drive shaft 3, and the slow-release assembly 5 can be used for buffering the inertial impact formed by the backflow of fluid and can also be used for slowing down the inertial kinetic energy of the impeller 2.

[0032] Referring to Figure 1 , Figure 2 and Figure 3In the embodiment of the present application, the pump shell 1 is provided in a cylindrical shape, one end of the pump shell 1 is provided as a water inlet end, the other end of the pump shell 1 is provided as a water outlet end, the water inlet end is located below the water outlet end, a mounting seat is fixedly arranged on the outer wall of the pump shell 1, the driving motor 6 is fixedly arranged on the mounting seat, the driving shaft 3 is rotatably arranged on the pump shell 1, bearings and mechanical seals are arranged on the connection position between the driving shaft 3 and the pump shell 1, the mechanical seals can prevent water from overflowing during the operation of the axial flow pump, one end of the driving shaft 3 is fixedly connected with the output end of the driving motor 6, and the impeller 2 is arranged at the end of the driving shaft 3 away from the driving motor 6. The impeller 2 is made of a metal conductor material, and in the embodiment, the impeller 2 can be made of alloy steel.

[0033] With reference to Figure 3 , Figure 4 and Figure 5 In the embodiment of the present application, the connecting assembly 4 includes an input piece 41, a transmission piece 43, an output piece 42, a first meshing piece 44 and a second meshing piece 45, a guide vane body is fixedly sleeved at the end of the driving shaft 3 away from the driving motor 6, the guide vane body is provided in a half-spindle shape, that is, the end of the guide vane body close to the driving motor 6 is arranged in a smooth transition with the driving shaft 3, an installation cavity is arranged on the surface of the guide vane body away from the driving motor 6, and the input piece 41 is fixedly embedded in the installation cavity. The input piece 41 is provided in a disc shape, an input shaft 411 is fixedly arranged on one side end surface of the input piece 41, an installation groove 412 is arranged on the side end surface of the input piece 41 away from the input shaft 411, a limiting end cover is further arranged on the end surface of the input piece 41 provided with the installation groove 412, and the input shaft 411 is fixedly connected with the end of the driving shaft 3 away from the driving motor 6.

[0034] The transmission piece 43 is provided in a disc shape, the transmission piece 43 is rotatably arranged in the installation groove 412, the first wedge-shaped groove 431 and the second wedge-shaped groove 432 are arranged in penetration on the transmission piece 43, the first wedge-shaped groove 431 and the second wedge-shaped groove 432 are in communication, the communication position of the first wedge-shaped groove 431 and the second wedge-shaped groove 432 is provided as an insertion cavity 433, the first wedge-shaped groove 431 and the second wedge-shaped groove 432 are symmetrically arranged with the center line position of the insertion cavity 433 as the center, two groups of the first wedge-shaped groove 431 and the second wedge-shaped groove 432 are respectively circumferentially arranged on the transmission piece 43, an insertion hole is arranged on the transmission piece 43, and the insertion hole is coaxially arranged with the transmission piece 43.

[0035] The output member 42 comprises an output shaft 421 and a yoke portion 422, one end of the yoke portion 422 is fixedly arranged at one end of the output shaft 421, one end of the output shaft 421 is rotationally connected with the insertion hole, and the end of the yoke portion 422 away from the output shaft 421 is insertedly matched with the insertion cavity 433, and the yoke portion 422 is provided with two groups, the two groups of yoke portions 422 are circumferentially distributed on the output shaft 421, and the impeller 2 is fixedly sleeved at one end of the output shaft 421 away from the input member 41. The output member 42 is rotationally arranged on the input member 41 through an end cover, and the end cover is rotationally connected with the output shaft 421, and a face shaft bearing is further arranged between the end cover and the yoke portion 422.

[0036] Referring to Figure 4 and Figure 5 In the embodiment, the first engaging member 44 comprises a first roller 441, a first abutting column 442 and a first spring 443, the inner wall of the first wedge-shaped groove 431 is provided with a first accommodating groove 434, the first abutting column 442 is slidingly arranged in the first accommodating groove 434, the first spring 443 is arranged in the first accommodating groove 434, one end of the first spring 443 is connected with one end of the first abutting column 442, the other end of the first spring 443 is connected with the inner wall of the first accommodating groove 434, and the end of the first abutting column 442 away from the first spring 443 is in active abutment with the first roller 441.

[0037] The second engaging member 45 comprises a second roller 451, a second abutting column 452 and a second spring 453, the second engaging member 45 is symmetrically arranged with the first engaging member 44, the second wedge-shaped groove 432 is symmetrically arranged with the first wedge-shaped groove 431, the second engaging member 45 is arranged in the second wedge-shaped groove 432, the yoke portion 422 is located between the first roller 441 and the second roller 451, one side of the yoke portion 422 is in sliding abutment with the outer circumferential wall of the first roller 441, and the other side of the yoke portion 422 is in sliding abutment with the outer circumferential wall of the second roller 451. The first engaging member 44 and the second engaging member 45 are also symmetrically arranged with the center line of the insertion cavity 433 as the center, and each of the first engaging member 44 and the second engaging member 45 is circumferentially provided with two groups on the input member 41.

[0038] By sliding the first roller 441 and the second roller 451 in the wedge-shaped groove and correspondingly applying the pre-tightening force by the first spring 443 and the second spring 453, the engagement / disengagement switching can be realized within milliseconds in the input direction change moment, which greatly improves the emergency response speed to the sudden working condition, and is particularly suitable for the water power impact protection scene of sudden water level change in mountainous area or sudden stop of pump station.

[0039] More specifically, in the embodiment, the clockwise rotation of the input member 41 is set as the first rotation direction, and the counterclockwise rotation of the input member 41 is set as the second rotation direction. When the driving shaft 3 drives the input member 41 to rotate in the first rotation direction, the corresponding yoke portion 422 will have a tendency to deflect and press the first roller 441 in the second rotation direction, and the first roller 441 will rotate freely in the first wedge-shaped groove 431. A wedge-shaped cavity is formed by the second wedge-shaped groove 432, the inner wall of the mounting groove 412, and one side surface of the yoke portion 422. The second roller 451 in the second wedge-shaped groove 432 is pressed by the second spring 453 to the narrow part of the wedge-shaped cavity, and a large friction force is generated between the second roller 451, the inner wall of the mounting groove 412, and one side surface of the yoke portion 422, thereby transmitting the torque from the input member 41 to the output member 42, and further realizing the rotation of the output member 42 in the first rotation direction driven by the input member 41. Since the first wedge-shaped groove 431 and the second wedge-shaped groove 432 are symmetrically arranged, and the first engaging member 44 and the second engaging member 45 are also symmetrically arranged, when the driving shaft 3 drives the input member 41 to rotate in the second rotation direction, the second roller 451 will rotate freely in the second wedge-shaped groove 432, and the first roller 441 will transmit the torque from the input member 41 to the output member 42 due to the large friction force generated between the inner wall of the mounting groove 412 and one side surface of the yoke portion 422, thereby realizing the rotation of the output member 42 in the second rotation direction driven by the input member 41.

[0040] When the driving shaft 3 suddenly stops rotating, the inertia generated by the instantaneous stop will drive the impeller 2 to rotate at high speed relative to the driving shaft 3. At this time, the output member 42 acts as the driving member, and the output shaft 421 will bear a large torque load. If the driving shaft 3 drives the input member 41 to rotate in the first rotation direction at the initial stage, the corresponding output shaft 421 will drive in the first rotation direction, the yoke portion 422 will press the second roller 451 to one side, and the first roller 441 on the other side will be subjected to the friction force of the inner wall of the mounting groove 412. However, since the first roller 441 is in sliding abutment with one end of the first abutment column 442, and the other end of the first abutment column 442 is connected with the first spring 443, the first roller 441 will have a tendency to deflect to the side of the center of the transmission member 43 under the action of the friction force of the inner wall of the mounting groove 412, thereby causing the first roller 441 to press the abutment column into the first accommodating groove 434, and further causing the first roller 441 to rotate freely in the first wedge-shaped groove 431. Therefore, when the driving shaft 3 suddenly stops rotating, the impeller 2 will rotate freely on the driving shaft 3, and will not apply a torque to the driving shaft 3 in the opposite direction.

[0041] Due to the engagement mechanism in the connecting assembly 4 is in the "idling" state under the reversed working condition of the impeller 2, the reverse stress loading caused by inertia driving can be greatly reduced, the fatigue wear risk of key structural parts such as bearings, shaft couplings, motor shafts and the like can be reduced, and especially in the mountainous area or emergency drainage scene with high-frequency sudden flow state changes, the safe and stable operation period and service life of the axial flow pump can be improved.

[0042] With reference to Figure 2 and Figure 3 In the embodiment of the present application, the slow-release assembly 5 includes a barrier 55, a shunt pipe 51, a piston block 53, a blocking plate 52, an overflow pipe 54, an elastic telescopic rod 57 and a magnetic block 56, a support frame 11 is fixedly arranged in the pump shell 1, the barrier 55 is fixedly arranged on the support frame 11, the barrier 55 is arranged as a tapered pipe body with elastic deformation capability, the barrier 55 is made of high-strength and ductile material, which makes the barrier 55 have excellent elastic memory and corrosion resistance, can work stably in high-humidity, high-pressure and impurity environment for a long time, prolongs the service life of the axial flow pump and improves the system durability.

[0043] The axial two ends of the barrier 55 are respectively arranged as an injection end and an outflow end, the inner diameter of the injection end is larger than that of the outflow end, the barrier 55 divides the pump shell 1 into two chambers, the two chambers are respectively arranged as a first chamber 12 and a second chamber, the barrier 55 is located in the first chamber 12, the impeller 2 is arranged in the second chamber 13, and a plurality of groups of liquid discharge holes are uniformly arranged on the barrier 55.

[0044] The shunt pipe 51 is arranged as a " " shaped square pipe, the shunt pipe 51 is arranged on the pump shell 1, one end of the shunt pipe 51 is in communication with the first chamber 12, the other end of the shunt pipe 51 is fixedly connected with the outer wall of the second chamber 13, the piston block 53 is slidingly arranged in the shunt pipe 51, the piston block 53 divides the shunt pipe 51 into two independent chambers, the two independent chambers are respectively arranged as a shunt chamber 511 and a piston chamber 512, the shunt chamber 511 is in communication with the first chamber 12, a limiting block 513 is fixedly arranged on the inner wall of the shunt chamber 511, the limiting block 513 is located on the side of the piston block 53 close to the shunt chamber 511, and the piston block 53 is in abutment with the limiting block 513.

[0045] The overflow pipe 54 is fixedly arranged on the shunt pipe 51, the pipe diameter of the overflow pipe 54 is much smaller than that of the shunt pipe 51, one end of the overflow pipe 54 is in communication with the shunt chamber 511, and the piston block 53 locally blocks the end of the overflow pipe 54 close to the shunt chamber 511, the other end of the overflow pipe 54 is in communication with the second chamber 13, and the shunt chamber 511 is always in communication with the second chamber 13 through the overflow pipe 54. A one-way valve is installed at the end of the overflow pipe 54 close to the second chamber 13, and the one-way valve can prevent the water in the second chamber 12 from entering the shunt pipe 51.

[0046] The blocking plate 52 is rotatably arranged at one end of the shunt pipe 51, and a torsion spring is arranged at the rotatable connection between the blocking plate 52 and the inner wall of the shunt pipe 51. The other end of the blocking plate 52 is movably abutted against the inner wall of the shunt pipe 51, and the blocking plate 52 is arranged obliquely on the shunt pipe 51. The blocking plate 52 is located at the end of the shunt pipe 51 that is in communication with the first chamber 12.

[0047] The piston chamber 512 is filled with hydraulic oil, and the magnetic block 56 is slidably arranged in the piston chamber 512. The magnetic block 56 is located at the end of the shunt pipe 51 that is away from the shunt chamber 511. In the initial state, a compression gap is reserved between the side of the magnetic block 56 that is away from the piston chamber 512 and the outer wall of the second chamber 13. In this embodiment, the magnetic block 56 can be a neodymium iron boron magnetic block, and the inner wall of the piston chamber 512 is magnetically shielded. A sliding frame is mounted on the magnetic block 56, so as to facilitate the sliding of the magnetic block 56 in the piston chamber 512. The elastic telescopic rod 57 is arranged in the piston chamber 512. One end of the elastic telescopic rod 57 is fixedly connected with the magnetic block 56, and the other end of the elastic telescopic rod 57 is fixedly connected with the inner wall of the shunt pipe 51.

[0048] In this embodiment, the four groups of slow-release assemblies 5 are arranged in a circle around the center line of the pump shell 1.

[0049] In more detail, once the axial flow pump suddenly loses driving force or the pump house appears abnormal during operation, it will inevitably cause the downstream water body to flow back into the pump body due to gravity or inertia, forming a short-time high-intensity reverse water flow impact. When these reverse water flow impacts flow from the outflow end to the injection end in the opposite direction of the fluid, the synergistic effect of the reverse water flow pressure and the elastic recovery force of the pipe wall causes the outflow end to shrink and gather towards the center of the lumen, achieving self-sealing of the outflow end. In this way, the reverse water flow can be forced to push open the blocking plate 52 and enter the shunt pipe 51, and the high-intensity reverse water flow acts on the piston block 53, causing the piston block 53 to slide downward and push the magnetic block 56 to move closer to the pump shell 1.

[0050] Since the impeller 2 is made of metal conductor, when the conductor (such as alloy steel) moves in the magnetic field, the induced current is generated by cutting the magnetic induction lines, and the current is affected by the Ampere force in the magnetic field, and the direction is opposite to the movement of the conductor, thereby generating a damping force to hinder the movement of the conductor. The impeller 2 originally rotating due to inertia will be gradually slowed down under the action of the gradually closing magnetic block 56, and since the blocking plate 52 is arranged obliquely, once the reverse water flow is injected into the shunt pipe 51, it cannot be discharged from one end of the shunt pipe 51, but can only be discharged into the second chamber 13 through the overflow pipe 54, and the diameter of the overflow pipe 54 is smaller than that of the shunt pipe 51. Therefore, even if the magnetic block 56 is gradually reset under the action of the elastic expansion rod 57, since the injected reverse water flow cannot be quickly discharged, the magnetic block 56 will continue to slow down the impeller 2 for a certain period of time, preventing the impeller 2 from rotating at high speed under the action of inertia and causing damage to the impeller 2 or the bearing supporting the impeller 2 to bear additional load and wear caused by high-speed reverse rotation.

[0051] At the same time, the inertia impact of the reverse water flow is gradually released by the blocking piece 55, the shunt pipe 51, the piston block 53 and the impeller 2, effectively protecting the drive shaft 3 and the impeller 2.

[0052] Under normal working condition, when the impeller 2 drives the water flow from the injection end to the outflow end, the fluid pressure drives the outflow end to expand outward to open the flow channel, the magnetic block 56 is away from the impeller 2, and the axial flow pump operates normally.

[0053] The implementation principle of the axial flow pump with protection function in the embodiment of the application is as follows: in normal operation, the driving motor 6 drives the impeller 2 to rotate and pump fluid through the driving shaft 3 and the connecting assembly 4, at this time the blocking piece 55 is opened, and the magnetic block 56 is away from the impeller 2. When the driving shaft 3 suddenly stops, the impeller 2 rotates at high speed due to inertia, the connecting assembly 4 realizes dynamic separation of movement through the first meshing piece 44 and the second meshing piece 45, so that the impeller 2 is decoupled from the driving shaft 3, avoiding reverse impact on the driving system; at the same time, the reverse water flow is formed by the backflow of water, forcing the outflow end of the blocking piece 55 to be self-sealed, the high-pressure water flow pushes open the blocking plate 52 to enter the shunt pipe 51, drives the piston block 53 to move the hydraulic oil, and then drives the magnetic block 56 to approach the rotating metal impeller 2, the impeller 2 cuts the magnetic induction lines to generate eddy current and is hindered by the Ampere force to consume its kinetic energy; at the same time, the water flow in the shunt pipe 51 can only be slowly discharged through the overflow pipe 54, delaying the reset of the magnetic block 56 and continuously braking the impeller 2 until it stops. Through the dynamic separation of the connecting assembly 4 and the multi-stage release of the slow-release assembly 5, the driving shaft 3, the impeller 2 and the bearing are effectively protected from damage caused by sudden stop and inertia impact of fluid backflow.

[0054] The above are preferred embodiments of the application, which do not limit the protection scope of the application, therefore: any equivalent changes made on the structure, shape and principle of the application shall be covered within the protection scope of the application.

Claims

1. An axial flow pump with protection function, comprising a pump shell (1), an impeller (2) arranged inside the pump shell (1), and a driving shaft (3) for driving the impeller (2) to rotate, the pump shell (1) is provided with an inlet end and an outlet end, characterized in that: a connecting assembly (4) is arranged between the impeller (2) and the driving shaft (3), the connecting assembly (4) comprises an input member (41), an output member (42), a transmission member (43), a first engaging member (44) and a second engaging member (45), the output member (42) is rotatably arranged on the input member (41), the input member (41) is provided with an input shaft (411), one end of the input shaft (411) is fixedly connected with the driving shaft (3), the output member (42) is provided with an output shaft (421), the output shaft (421) is fixedly connected with the impeller (2), and the transmission member (43) is arranged between the input member (41) and the output member (42). When the input member (41) rotates in a first rotation direction, the output member (42) transmits torque by engaging with the input member (41) through the second engaging member (45), and the first engaging member (44) is in a free rotation state; when the input member (41) rotates in a second direction, the second engaging member (45) is in a free rotation state, and the output member (42) transmits torque by engaging with the input member (41) through the first engaging member (44). When the rotation speed of the output member (42) exceeds the rotation speed of the input member (41), both the first engaging mechanism and the second engaging mechanism are in a free rotation state. The input member (41) is arranged in a disc shape, one side of the input member (41) is fixedly provided with an input shaft (411), one end of the input shaft (411) is fixedly connected with the driving shaft (3), a mounting groove (412) is formed on the side of the input member (41) away from the input shaft (411), the transmission member (43) is rotatably arranged in the mounting groove (412), and the transmission member (43) is in transmission connection with the output member (42).

2. The axial flow pump with protection function according to claim 1, characterized in that: ​ 3. The axial flow pump with protection function according to claim 2, characterized in that: The transmission member (43) is provided in a disc shape, a first wedge-shaped slot (431) and a second wedge-shaped slot (432) are provided through the transmission member (43), the first wedge-shaped slot (431) is communicated with the second wedge-shaped slot (432), and a plug-in cavity (433) is arranged at the communication position of the first wedge-shaped slot (431) and the second wedge-shaped slot (432); the first engaging member (44) comprises a first roller (441), a first abutting column (442) and a first spring (443), a first containing slot (434) is arranged on the inner wall of the first wedge-shaped slot (431), the first abutting column (442) is slidingly arranged in the first containing slot (434), the first spring (443) is arranged in the first containing slot (434), one end of the first spring (443) is connected with one end of the first abutting column (442), the other end of the first spring (443) is connected with the inner wall of the first containing slot (434), and the end of the first abutting column (442) away from the first spring (443) is slidingly abutted with the first roller (441); the second engaging member (45) comprises a second roller (451), a second abutting column (452) and a second spring (453), the second engaging member (45) is arranged in the same manner as the first engaging member (44), the second wedge-shaped slot (432) is arranged in the same manner as the first wedge-shaped slot (431), the first wedge-shaped slot (431) and the second wedge-shaped slot (432) are symmetrically arranged with the center line of the plug-in cavity (433) as the center, and the second engaging member (45) is arranged in the second wedge-shaped slot (432).

4. The axial flow pump with protection function according to claim 3, characterized in that: The output member (42) comprises an output shaft (421) and a fork part (422), one end of the output shaft (421) is rotationally connected with the transmission member (43), one end of the fork part (422) is fixedly arranged on the output shaft (421), the end of the fork part (422) away from the output shaft (421) is plug-in matched with the plug-in cavity (433), one side of the fork part (422) is movably abutted with the first roller (441), the other side of the fork part (422) is movably abutted with the second roller (451), the fork part (422) is provided with two groups, the two groups of fork parts (422) are circumferentially distributed on the output shaft (421), and the impeller (2) is fixedly arranged on the end of the output shaft (421) away from the input member (41).

5. The axial flow pump with protection function according to claim 1, characterized in that: The slow-release assembly (5) further comprises a shunt pipe (51) and a blocking plate (52), the shunt pipe (51) is arranged on the pump shell (1), one end of the shunt pipe (51) is communicated with one end close to the water outlet end of the pump shell (1), the other end of the shunt pipe (51) is fixedly connected with the outer wall close to the water inlet end of the pump shell (1), a piston block (53) is slidably arranged in the shunt pipe (51), the piston block (53) divides the shunt pipe (51) into two independent cavities, the two independent cavities are respectively arranged as a shunt cavity (511) and a piston cavity (512), an overflow pipe (54) is arranged on the shunt pipe (51), one end of the overflow pipe (54) is communicated with the shunt cavity (511), the other end of the overflow pipe (54) is communicated with the pump shell (1), the piston block (53) partially blocks one end of the overflow pipe (54) close to the shunt pipe (51), the blocking plate (52) is rotationally arranged in the shunt pipe (51), and the blocking plate (52) is arranged in an inclined manner relative to the inner wall of the shunt pipe (51), and the blocking plate (52) is located at one end of the shunt pipe (51) communicated with the pump shell (1).

6. The axial flow pump with protection function according to claim 5, characterized in that: The slow-release assembly (5) further comprises a barrier (55), a support frame (11) is fixedly arranged in the pump shell (1), the barrier (55) is arranged on the support frame (11), the barrier (55) divides the pump shell (1) into two cavities, the two cavities are respectively arranged as a first cavity (12) and a second cavity (13), the first cavity (12) is communicated with the water outlet end of the pump shell (1), one end of the shunt pipe (51) is communicated with the first cavity (12), the barrier (55) is located in the first cavity (12), the impeller (2) is arranged in the second cavity (13), the barrier (55) is arranged as a conical pipe body with elastic deformation ability, the barrier (55) is made of high-strength ductile material, the axial two ends of the barrier (55) are respectively arranged as an injection end and an outflow end, the outflow end of the barrier (55) is communicated with the first cavity (12), the inner diameter of the injection end of the barrier (55) is greater than the inner diameter of the outflow end of the barrier (55), when the fluid flows reversely from the outflow end of the barrier (55) to the injection end of the barrier (55), the synergistic effect of the fluid reverse flow pressure and the elastic force of the pipe wall of the barrier (55) makes the outflow end of the barrier (55) shrink and gather towards the lumen center of the barrier (55), thereby realizing self-sealing of the outflow end of the barrier (55).

7. The axial flow pump with protection function according to claim 5, characterized in that: The slow-release component (5) further comprises a magnetic block (56) and an elastic telescopic rod (57), the magnetic block (56) is slidingly arranged in the piston chamber (512), the piston chamber (512) is filled with hydraulic oil, the magnetic block (56) is located at one end of the shunt pipe (51) away from the shunt chamber (511), the elastic telescopic rod (57) is arranged in the piston chamber (512), one end of the elastic telescopic rod (57) is connected with the magnetic block (56), and the other end of the elastic telescopic rod (57) is connected with the inner wall of the shunt pipe (51), and the impeller (2) is made of a metal conductor material.

8. The axial flow pump with protection function according to claim 7, characterized in that: A limiting block (513) is fixed on the inner wall of the shunt chamber (511), the limiting block (513) is located on the side of the piston block (53) close to the shunt chamber (511), and the piston block (53) is in abutment with the limiting block (513).

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