A canned electric pump with a pump structure in which each end of the motor shaft drives a pump

Abstract

A shielded electric pump with a pump structure driven by each of the two ends of the motor shaft, comprising: a pump housing, a rotor assembly, a first pump cover, a second pump cover, and a stator assembly, wherein the two ends of the rotating shaft of the rotor assembly drive an upper impeller and a lower impeller; characterized in that: it also includes a pressure plate, the first pump cover and one axial end of the pump housing are matched to form a first impeller cavity for accommodating the upper impeller, the pump housing is formed with a stator cavity for accommodating the stator assembly and a tubular inner shell with two openings at both ends, the inner cavity of the inner shell accommodates the rotor assembly, the pressure plate is fixed to the other axial end of the pump housing and watertightly seals the stator cavity, and the second pump cover and the pressure plate are matched to form a second impeller cavity for accommodating the lower impeller. The shielded electric pump of this design requires fewer parts and installation procedures, simplifies the structure and improves assembly efficiency.

Description

Technical Field

[0001] The present invention relates to a canned electric pump with a pump structure driven by each of two ends of a motor shaft, and its IPC classification belongs to F04D13 / 06 or F04D 29 / 22. Background Art

[0002] The shielded electric pump of the prior art, in which each end of the motor shaft drives a pump structure, is described in the prior application CN108999790A "A double-outlet water pump", and includes a housing, a middle plate, a sealing plate, a main shaft, a first impeller, a second impeller, a first side cover, and a second side cover. The middle plate is provided with a fixed pipe, and the middle plate is fixedly mounted on the housing and forms a mounting cavity for mounting the stator between the middle plate and the housing. A first pump chamber for accommodating the first impeller is formed between the first side cover and the sealing plate, and a second pump chamber for accommodating the second impeller is formed between the second side cover and the housing. The main shaft rotates and simultaneously drives the first impeller and the second impeller arranged on both sides of the main shaft to rotate, thereby realizing double-sided drainage of the water pump. The rotating shaft of this structure needs to pass through the screw-assembled housing, middle plate, sealing plate and other parts, which has poor centering, is difficult to assemble, has a complex structure, and lacks consideration for the reasonable installation of the control panel.

[0003] For relevant terminology and common knowledge, please refer to the Mechanical Engineering Handbook and Electrical Engineering Handbook published by the Machinery Industry Press in 1983 or 1997, as well as the national standard GB / T 7021-2019 Terminology of Centrifugal Pumps. Summary of the invention

[0004] In order to improve the problems described in the background technology, the present invention provides a canned electric pump with a pump structure driven by each of the two ends of the motor shaft, which has a simple structure, is easy to assemble and has good sealing performance.

[0005] The technical solution of the present invention is:

[0006] A shielded electric pump with a pump structure driven by each of the two ends of the motor shaft, comprising: a pump casing, a rotor assembly, a first pump cover, a second pump cover, and a stator assembly, wherein an upper impeller and a lower impeller are fixed to each of the two ends of the rotating shaft of the rotor assembly, and characterized in that: it also includes a pressure plate, the first pump cover and the pump casing are matched at one axial end to form a first impeller cavity for accommodating the upper impeller, the pump casing is formed with a stator cavity for accommodating the stator assembly and a tubular inner casing with openings at both ends, the inner cavity of the inner casing accommodates the rotor assembly, the pressure plate is fixedly arranged at the other axial end of the pump casing and watertightly seals the stator cavity, and the second pump cover and the pressure plate are matched to form a second impeller cavity for accommodating the lower impeller.

[0007] According to the technical solution, the pump housing of the shielded electric pump can be integrally injection molded to form a stator cavity for accommodating the stator assembly and a tubular inner shell with openings at both ends for accommodating the rotor assembly. During assembly, the stator assembly and the rotor assembly are coaxially placed on the outer and inner peripheries of the inner shell of the pump housing, respectively, and then the pressure plate is watertightly sealed at the opening of the stator cavity of the pump housing to complete the installation of the two. Therefore, the shielded electric pump of this design requires fewer parts and installation procedures and has a relatively simple structure, especially the good concentricity of the stator and rotor, which is conducive to improving assembly efficiency and motor efficiency, while the sealing performance is still good.

[0008] Furthermore, the specific structure of the pressure plate fixedly arranged at the other axial end of the pump housing and watertightly sealing the stator cavity is as follows: an annular first sealing ring is arranged between the outer shell of the pump housing and the pressure plate; an annular pressure plate groove is arranged on the side of the pressure plate facing the stator cavity, the inner housing is inserted and installed in the pressure plate groove, and a second sealing ring is arranged between the inner housing and the pressure plate. The structure is simple and easy to install.

[0009] Furthermore, the second sealing ring is a hollow columnar structure with an annular groove. This design uses the second sealing ring to wrap the opening of the inner shell and insert it into the pressure plate groove, thereby increasing the sealing area between the inner shell and the pressure plate and improving the sealing between the inner shell and the pressure plate.

[0010] Furthermore, the axial single-side cross section of the second sealing ring is "L" shaped, and the second sealing ring is closely attached to the peripheral cylindrical surface of the pressure plate groove and has a plurality of annular second sealing ring convex ribs. This design facilitates the gas in the pressure plate groove to be discharged from the gap between the contact surface of the inner shell and the pressure plate groove when the inner shell is inserted and installed in the pressure plate groove, which is convenient for assembly.

[0011] Furthermore, the shielded electric pump with a pump structure driven by each of the two ends of the motor shaft also includes a control board and a side cover, the outer wall surface of the outer shell of the pump housing protrudes outwardly to form a cylindrical surrounding edge, the side cover is fixed on the surrounding edge, and the surrounding edge forms an installation cavity for installing the control board, and a through hole is provided on the outer wall surface to connect the stator cavity and the installation cavity. The design pump has a high degree of integration and a small overall volume.

[0012] Furthermore, the shielded electric pump with a pump structure driven by each of the two ends of the motor shaft also includes a conductive rod, which passes through the through hole, one end of which contacts the iron core on the stator assembly, and the other end is connected to the control board. This design uses the conductive rod passing through the pump housing to connect the iron core with the grounding wire on the control board, which is simple and reliable to assemble and achieve the grounding protection required by the implementation product standard.

[0013] Furthermore, the shielded electric pump with a pump structure in which each end of the motor shaft drives a pump further comprises an annular elastic block disposed between the pressure plate and the iron core, the conductive rod is provided with a protrusion protruding toward the iron core, the annular elastic block presses the conductive rod tightly and places the protrusion close to the axial end face of the iron core. This design enables the contact between the conductive rod and the iron core to reach a larger and more stable pressure, thereby achieving more reliable conduction.

[0014] Furthermore, the shielded electric pump with a pump structure driven by each of the two ends of the motor shaft also includes an upper bearing, a lower bearing and an annular third sealing ring for the shaft to pass through and install, and the inner ring of the third sealing ring has more than two radial protrusions of the annular third sealing ring ribs that are close to the shaft; the upper bearing is injection-molded and fixed to the annular end plate of the pump housing, and the third sealing ring is located between the magnetic core of the rotor assembly and the annular end plate, and is fixed to the annular end plate; or, the lower bearing is injection-molded and fixed to the pressure plate, and the third sealing ring is located between the magnetic core of the rotor assembly and the pressure plate, and is fixed to the pressure plate. This design is simple and reliable to assemble, and reduces the exchange of liquid in the first impeller chamber and the second impeller chamber, and improves the sealing effect between the first impeller chamber and the second impeller chamber.

[0015] Furthermore, the shielded electric pump of the structure of driving a pump at each end of the motor shaft further includes a clamping member for fixing and installing the third sealing ring, the clamping member includes a hollow cylindrical clamping member body, a hook provided on the axial end surface of the clamping member body, and a clamping member boss protruding radially inward from the inner ring of the clamping member body, the third sealing ring is clamped to the clamping member boss, and the clamping member is clamped to the end plate or the pressure plate. This design enables the third sealing ring to be stably clamped to the end plate or the pressure plate, preventing the third sealing ring from falling off during operation.

[0016] Furthermore, the third sealing ring includes a third sealing ring body in a hollow column, an outer sealing ring arranged on the outer periphery of the third sealing ring body, and a transition connector connecting the two. The outer sealing ring is provided with an outer sealing ring groove in the axial direction, and the axial end surface of the clamping part body protrudes a clamping part rib, and the outer sealing ring groove is sleeved on the clamping part rib. With this design, the third sealing ring can be clamped more firmly on the pump housing.

[0017] Furthermore, the shielded electric pump with a pump structure in which each end of the motor shaft drives a pump also includes an upper bearing, a lower bearing and a fourth hollow cylindrical sealing ring for the shaft to pass through and install, and the inner ring of the fourth sealing ring radially protrudes more than two annular fourth sealing ring ribs that are close to the shaft; the annular end plate of the pump housing is provided with a concave bearing groove, and the radial direction of the bearing groove is provided with a protruding upper bearing groove rib or a concave end plate groove, and the upper bearing sleeve is provided with a fourth sealing ring and is clamped on the bearing groove; or, the axial end face of the pressure plate is provided with a concave pressure plate bearing groove, and the radial direction of the pressure plate bearing groove is provided with a protruding pressure plate bearing groove rib or a concave pressure plate groove, and the lower bearing sleeve is provided with a fourth sealing ring and is clamped on the pressure plate bearing groove. This design reduces the exchange of liquid in the first impeller chamber and the second impeller chamber, and improves the sealing effect between the first impeller chamber and the second impeller chamber.

[0018] Furthermore, the shielded electric pump with a pump structure in which each end of the motor shaft drives a pump also includes an upper bearing, a lower bearing and an annular fifth sealing ring for the rotating shaft to pass through and install, the annular end plate of the pump housing is concave to form a first bearing groove, the upper bearing is sleeved with a fifth sealing ring and installed on the first bearing groove, and the rotor assembly also includes a plastic part fixed on the rotating shaft by injection molding, the end surface of the annular end plate of the plastic part facing the pump housing protrudes with several annular rotor ribs, the end surface of the end plate facing the plastic part protrudes with several annular pump housing ribs, and the rotor ribs and the pump housing ribs are staggered and inserted to form a labyrinth seal structure. The design uses the fifth sealing ring to seal between the first impeller chamber and the inner shell, avoiding mutual exchange when different temperatures or different liquids are respectively set in the first impeller chamber and the second impeller chamber, thereby expanding the use range of the pump.

[0019] Furthermore, the axial protrusion of the upper bearing is exposed on the annular end plate of the pump housing, and the axial protrusion of the lower bearing is exposed on the axial end surface of the pressure plate. This design limits the axial movement of the rotor assembly and avoids direct wear and damage between the upper impeller and the end plate and between the lower impeller and the pressure plate, thereby improving the safety of the pump.

[0020] Furthermore, the shielded electric pump with a pump structure driven by each of the two ends of the motor shaft also includes an impeller insert molded on each of the upper impeller and the lower impeller, and the impeller insert protrudes axially from the outer end surface of the shaft disc into which the impeller is embedded. This design avoids direct contact and wear between the impeller and the adjacent bearing, thereby increasing the life of the impeller.

[0021] Furthermore, the two ends of the rotating shaft are respectively provided with axial holes and rotating shaft bosses for assembling the upper impeller and the lower impeller, the rotating shaft bosses are provided with radially symmetrical flat positions, and the impeller insert is provided with an insert hole with a flat position groove for the rotating shaft to be inserted and assembled. This design facilitates the processing of the rotating shaft and improves the coaxiality of the upper and lower impellers after assembly.

[0022] Furthermore, a pressure plate through hole is provided on the axial end surface of the pressure plate, and the pressure plate through hole connects the second impeller cavity with the rotor cavity surrounded by the pressure plate and the inner shell and accommodating the rotor assembly. The through hole of this design connects the second impeller cavity with the rotor cavity, and the liquid in the impeller cavity can pass through the pressure plate through hole to dissipate heat to the magnetic core on the rotor assembly.

[0023] Furthermore, the upper impeller and the lower impeller are co-directional impellers, that is, both are forward impellers or both are backward impellers or both are radial impellers, which is beneficial to reducing vibration noise.

[0024] Furthermore, the outer diameter of the upper impeller is not equal to the outer diameter of the lower impeller. This design allows the two pump structures to be used on equipment with different displacement requirements, thereby expanding the application range of the pump.

[0025] Furthermore, a side plate with a mounting hole protrudes from the radial end surface of the side cover. This design allows the external power line to be fixed on the side plate, which is beneficial to the arrangement of the external power line.

[0026] The present invention will be described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the three-dimensional structure of the canned motor pump of the present invention;

[0028] Figure 2 It is a schematic diagram of the exploded structure of the first embodiment of the canned motor pump of the present invention;

[0029] Figure 3 is a cross-sectional view of a first embodiment of a canned motor pump of the present invention;

[0030] Figure 4 yes Figure 3 A partial enlarged view of middle A;

[0031] Figure 5 yes Figure 3 A partial enlarged view of B in the middle;

[0032] Figure 6 is a cross-sectional view of a second embodiment of a canned motor pump of the present invention;

[0033] Figure 7 yes Figure 6 A partial enlarged view of middle C;

[0034] Figure 8 is a cross-sectional view of a third embodiment of a canned motor pump of the present invention;

[0035] Fig. 9 yes Figure 8 A partial enlarged view of D in the middle;

[0036] Fig.10 It is a three-dimensional structural diagram of the pump housing of the canned motor pump of the present invention;

[0037] Fig.11 It is a three-dimensional structural diagram of the pump housing of the canned motor pump of the present invention from another angle;

[0038] Fig.12 is a cross-sectional view of a rotor assembly with an impeller of a first embodiment of a canned motor pump of the present invention;

[0039] Fig.13 It is a schematic diagram of the three-dimensional structure of the second sealing ring of the canned motor pump of the present invention;

[0040] Fig.14 It is the three-dimensional structure of the third sealing ring of the canned motor pump of the present invention;

[0041] Fig.15 It is a three-dimensional structural schematic diagram of the rotating shaft of the canned motor pump of the present invention;

[0042] Fig.16It is a three-dimensional structural schematic diagram of a pressure plate of a canned motor pump of the present invention;

[0043] Fig.17 It is a schematic diagram of the three-dimensional structure of the second embodiment of the second sealing ring of the canned motor pump of the present invention;

[0044] Fig.18 is a cross-sectional view of a second embodiment of a canned motor pump according to the present invention using a second sealing ring;

[0045] Fig.19 yes Fig.18 A partial enlarged view of middle E;

[0046] Fig. 20 is a cross-sectional view of a fourth embodiment of a canned motor pump of the present invention;

[0047] Fig.21 yes Fig. 20 A partial enlarged view of middle F;

[0048] Fig. 22 is a schematic diagram of the exploded structure of the third sealing ring and the clamping member in the fourth example;

[0049] Among them: 10-stator cavity, 11-rotor cavity, 20-installation cavity, 30-stator assembly, 31-iron core, 40-first impeller cavity, 50-second impeller cavity, 60-screw, 70-rotor cavity, 100-pump casing, 100'-pump casing, 100"-pump casing, 100"'-pump casing, 110-inner casing, 120-outer casing, 121-edge, 122-through hole, 140"-pump casing rib, 160-end plate, 160'-end plate, 160"-end plate, 160"'-end plate, 161"-first bearing groove, 161"'-end plate installation groove, 163-end Plate rib, 166′-bearing groove, 167′-bearing groove rib, 170-clip, 171-hook, 172-clip boss, 173-clip body, 174-rib, 200-pressing plate, 210-pressing plate groove, 220-pressing plate through hole, 230-central through hole, 300-rotor assembly, 300′-rotor assembly, 310-rotating shaft, 311-axial hole, 312-rotating shaft boss, 320-magnetic core, 330-upper impeller, 331-upper blade, 340-lower impeller, 341-lower blade, 350-plastic part, 350′-plastic part, 3 51′-rotor rib, 361-upper bearing, 361′-upper bearing, 361″-upper bearing, 363′-upper bearing rib, 362-lower bearing, 362′-lower bearing, 370-impeller insert, 371-insert hole, 380-rotating shaft screw, 400-control panel, 500-side cover, 510-side plate, 511-mounting hole, 600-first pump cover, 610-first water inlet, 620-first water outlet, 700-second pump cover, 710-second water inlet, 720-second water outlet, 730-second pump cover rib, 810-first sealing ring, 8 20-second sealing ring, 820'-second sealing ring, 821-annular groove, 821'-second sealing ring rib, 822-second sealing ring body, 830-fifth sealing ring, 840-annular elastic block, 850-fourth sealing ring, 851-fourth sealing ring rib, 860-third sealing ring, 860'-third sealing ring, 861-third sealing ring rib, 861'-third sealing ring rib, 862'-third sealing ring body, 863'-outer sealing ring, 864'-transition connector, 865'outer sealing ring groove, 920-conductive rod, 921-bump DETAILED DESCRIPTION

[0050] See Figures 1 to 3 The shielded electric pump of each embodiment of the present invention, wherein each end of the motor shaft drives a pump, comprises a pump housing 100, a pressure plate 200 mounted on the pump housing 100, a rotor assembly 300 rotatably mounted on the pump housing 100, a stator assembly 30 mounted on the pump housing 100, a first pump cover 600 fixedly arranged on one axial side of the pump housing, and a second pump cover 700 fixedly arranged on the other axial side of the pump housing. Fig.12The rotor assembly 300 includes a rotating shaft 310, a magnetic core 320, and a plastic part 350 which is injection molded on the rotating shaft and fixes the magnetic core on the rotating shaft. The first pump cover 600 is provided with a first water inlet 610 for water inlet and a first water outlet 620 for water outlet, and the second pump cover 700 is provided with a second water inlet 710 for water inlet and a second water outlet 720 for water outlet. Figure 3 and Figures 10 to 12 The pump housing 100 is made by one-step injection molding, and includes an annular end plate 160, a tubular inner housing 110 with both ends opened and connected to the end plate 160, and an outer housing 120 arranged on the outer periphery of the inner housing 100 and connected to the end plate 160. The first pump cover 600 and the end plate 160 of the pump housing are matched to form a first impeller cavity 40 for accommodating the upper impeller 330. The inner housing 110, the outer housing 120 and the end plate 160 of the pump housing 100 form a stator cavity 10, and the end plate 160 and the hollow inner cavity of the inner housing 110 form a rotor cavity 70. During assembly, the stator assembly 30 is fixed in the stator cavity 10, the rotor assembly 300 is accommodated in the rotor cavity 70, one end of the rotating shaft 310 passes through the opening of the inner shell 100 at one end of the end plate 160 and extends to the outside of the end plate 160, the pressing plate 200 is fixed to the other end of the pump housing and seals the stator cavity 10 watertightly, so that the other end of the rotating shaft 310 passes through the central through hole 230 provided on the pressing plate 200 and extends to the outside of the pressing plate, the two ends of the rotating shaft 310 are respectively fixed with the upper impeller 330 and the lower impeller 340, the first pump cover 600 and the end plate 160 of the pump housing are matched to form a first impeller cavity 40 for accommodating the upper impeller 330, and the second pump cover 700 and the pressing plate 200 are matched to form a second impeller cavity 50 for accommodating the lower impeller 340. The rotation of the rotating shaft 310 drives the upper impeller 330 and the lower impeller 340 to rotate simultaneously, realizing the double-sided drainage of the centrifugal pump. The pump designed as above requires fewer parts and installation procedures, has a simple structure, and has good concentricity between the stator and rotor, which is beneficial to improving assembly efficiency and pump efficiency.

[0051] To improve the integration of the pump and reduce the overall volume. Figure 3 and Fig.11 The canned motor pump of the present invention with a pump structure driven by each of the two ends of the motor shaft further includes a control board 400 and a side cover 500. The outer wall surface of the outer shell 120 of the pump body protrudes outward and is integrally molded with the outer shell to form a cylindrical surrounding edge 121 by injection molding. The side cover 500 is fixed on the surrounding edge 121 and forms an installation cavity 20 with the surrounding edge 121. A through hole 122 is provided on the outer wall surface of the outer shell 120 to connect the stator cavity 10 and the installation cavity 20, and the control board 400 is assembled in the installation cavity 20.

[0052] See Figure 3 , 4 and Fig.13In the present invention, a specific embodiment of the pressure plate 200 is fixed to the other end of the pump housing and watertightly seals the stator cavity 10: the shielded electric pump with a pump structure driven by each of the two ends of the motor shaft also includes an annular first sealing ring 810 and a second sealing ring 820. The second sealing ring 820 includes a hollow annular second sealing ring body 822 and an annular groove 821 axially arranged on the second sealing ring body 822. An annular pressure plate groove 210 is arranged on the side of the pressure plate 200 facing the stator cavity 20. Figure 4 During assembly, the first sealing ring 810 is arranged between the outer shell 120 of the pump casing and the pressure plate 200. After the inner shell 110 of the pump casing is sleeved in the annular groove 821 of the second sealing ring 820, the inner shell 110 installed with the second sealing ring 820 is tightly inserted and installed in the pressure plate groove 210. Since the radial cross-section of the inner shell is relatively small, if a conventional O-ring is sleeved on the inner shell, it is easy for the inner shell to deform and cause water leakage. The above design uses a sealing ring with a hollow annular structure with a groove to wrap the inner shell as a whole and embed it into the pressure plate groove. While increasing the sealing area between the inner shell and the pressure plate, it can prevent the inner shell from deforming and causing gaps to cause water leakage, thereby improving the reliability of the seal.

[0053] See Figures 17 to 19 In another specific embodiment of the present invention, the pressure plate 200 is fixed at the other end of the pump housing and the stator cavity 10 is sealed watertightly. The shielded electric pump with a pump structure in which each end of the motor shaft drives a pump also includes an annular first sealing ring 810 arranged between the outer shell 120 of the pump housing and the pressure plate 200 and a second sealing ring 820' arranged between the inner shell 110 and the pressure plate 200. Among them, the second sealing ring 820' is a hollow annular column, and its axial single-side cross-section is "L" shaped. The second sealing ring 820' includes a plurality of annular second sealing ring ribs 821' protruding on the circumferential cylindrical surface of the second sealing ring 820'. The pressure plate 200 is provided with an annular pressure plate groove 210 on one side facing the stator cavity. During assembly, the second sealing ring 820' is placed in the pressure plate groove 210, and then the inner shell 110 of the pump body is inserted and the second sealing ring 820' is pressed tightly in the pressure plate groove 210. This design facilitates the gas in the pressure plate groove to be discharged from the gap between the inner shell and the contact surface of the pressure plate groove when the inner shell is inserted and installed in the pressure plate groove, which is convenient for assembly. Of course, as other embodiments, the pressure plate can be welded or use other annular sealing rings to seal the stator cavity opening of the pump housing.

[0054] In order to facilitate the implementation of grounding protection, the shielded electric pump of the present invention, in which each end of the motor shaft drives a pump structure, further includes a conductive rod 920. Figure 3 and Figure 4The conductive rod 920 passes through the through hole 122, one end of which contacts the stator core 31 on the stator, and the other end is connected to the control board 400. Furthermore, in order to prevent the conductive rod 920 from shifting during operation and failing to contact the core, the centrifugal pump of the present invention further includes an annular elastic block 840 disposed between the pressure plate 200 and the core 31, and a protruding bump 921 is disposed on the conductive rod 920, and the annular elastic block 840 presses the bump 921 of the conductive rod against the core 31.

[0055] To limit the interference between the plastic part or magnetic core of the rotor assembly and the axial end surface of the end plate or pressure plate of the pump body due to axial movement when the rotor assembly rotates. Figure 3 and Figure 5 The shielded electric pump with a pump structure driven by each of the two ends of the motor shaft also includes an upper bearing 361 and a lower bearing 362 for the shaft to pass through and install. The axial protrusion of the upper bearing 361 is exposed on the end plate 160 of the pump housing, and the axial protrusion of the lower bearing 362 is exposed on the axial end surface of the pressure plate 200. This design not only limits the amplitude of the axial movement of the rotor assembly, but also avoids direct wear and damage between the upper impeller and the end plate and between the lower impeller and the pressure plate, thereby improving the safety of the pump.

[0056] Furthermore, to avoid direct contact and wear between the upper or lower impeller and the upper or lower bearing, the service life of the upper and lower impellers is increased. Fig.12 The shielded electric pump with a pump structure driven by each of the two ends of the motor shaft also includes impeller inserts 370 respectively injected on the upper impeller 330 and the lower impeller 340, and the impeller inserts 370 protrude axially and are exposed on the outer end surfaces of the shaft discs of the upper impeller 330 and the lower impeller 340.

[0057] Further, see Fig.12 and Fig.15 , in order to facilitate the processing of the rotating shaft and improve the coaxiality of the upper and lower impellers after assembly. The two ends of the rotating shaft 310 are respectively provided with an axial hole 311 and a rotating shaft boss 312 for assembling the upper impeller and the lower impeller. The rotating shaft boss 312 is provided with symmetrical flat positions, and the impeller insert 370 is provided with an insert hole 371 with a flat position groove. Among them, the symmetrical flat positions on the rotating shaft boss 312 are specifically radially symmetrical notches set on the end of the rotating shaft. During assembly, after the insert holes 371 of the upper impeller 330 and the lower impeller 340 are inserted and installed on the rotating shaft boss 312 of the rotating shaft, the two are fixedly installed on the rotating shaft 310 with the rotating shaft screws 380 respectively.

[0058] See Figure 3 and 16 The axial end surface of the pressing plate 200 is provided with a pressing plate through hole 220, which connects the second impeller cavity 50 with the inner space of the inner shell 110. The through hole of this design connects the second impeller cavity with the inner shell, and the liquid in the impeller cavity can pass through the pressing plate through hole to dissipate heat to the magnetic core 320 in the inner shell.

[0059] See Figure 3 To facilitate the arrangement of external power lines, a side plate 510 with a mounting hole 511 is protruded on the radial end surface of the side cover 500 of the shielded electric pump of the present invention, in which each end of the motor shaft drives a pump structure.

[0060] See Fig.12 The upper impeller 330 of the present invention is provided with an upper blade 331, and the lower impeller 340 is provided with a lower blade 341. To ensure that the blades of the upper and lower impellers are in the same direction when the shaft rotates. That is, in the installed state, the rotation direction of the projections of the upper blade 331 and the lower blade 341 on the plane perpendicular to the axis is the same. After this design, the drainage efficiency on both sides of the centrifugal pump can be improved at the same time. Furthermore, in the centrifugal pump with drainage function at both ends of the present invention, the outer diameter of the upper impeller 330 is not equal to the outer diameter of the lower impeller 340. This design allows the pump to be used on equipment with different displacement requirements, thereby expanding the application range of the pump.

[0061] Embodiment 1:

[0062] See Figure 5 , 10 and Fig.14 In order to avoid the exchange of liquid in the first impeller chamber and the second impeller chamber, the shielded electric pump of the motor shaft of this embodiment, which drives a pump at each end, also includes an annular third sealing ring 860. The third sealing ring 860 includes more than two annular third sealing ring ribs 861 protruding radially on the inner ring for close contact with the rotating shaft 310 and a clamping groove 862 arranged on the axial end face. The upper bearing 361 is injection-molded and fixed on the annular end plate 160 of the pump housing. The end plate 160 has a first end plate rib 163 protruding axially on the side facing the pressure plate. After the third sealing ring 860 passes through the rotating shaft 310, it is clamped on the end plate rib 163 using the clamping groove 862. After the above design, the third sealing ring 860 is clamped between the magnetic core 31 of the rotor assembly and the end plate 160 of the pump housing. Of course, as other equivalent implementation examples, the lower bearing of the shielded electric pump with a pump structure driven by each of the two ends of the motor shaft is fixed on the pressure plate by injection molding, and the third sealing ring is installed between the magnetic core of the rotor assembly and the pressure plate after passing through the rotating shaft, and is fixed on the pressure plate by clamping. After this design, the first impeller cavity or the second impeller cavity is sealed with the inner shell, preventing the liquid in the first impeller cavity from flowing to the second impeller cavity through the inner shell, so that the pump can be applied to pumping equipment with different temperatures and / or different liquids.

[0063] Embodiment 2:

[0064] The difference between this embodiment and the first embodiment is the structure to prevent the liquid in the first impeller chamber and the second impeller chamber from exchanging. Figure 6 and Figure 7The shielded electric pump of the motor shaft of the present embodiment, each end of which drives a pump, further comprises a fourth sealing ring 850 of hollow cylindrical shape, the inner ring of which radially protrudes more than two annular fourth sealing ring ribs 851 which are close to the rotating shaft 310. The end surface of the end plate 161' of the pump body in the present embodiment is axially concave to form a bearing groove 166' with radially protruding bearing ribs 167', and the upper bearing 361' has radially protruding upper bearing ribs 363'. After the fourth sealing ring 850 is sleeved on the upper bearing 361', the upper bearing ribs 363' and the bearing ribs 167' are clamped on the bearing groove 166'. The bearing of this design is clamped on the end plate, which is convenient for maintenance and replacement. Of course, as an equivalent implementation method of this embodiment, the axial end face of the pressure plate is provided with a concave pressure plate bearing groove, the outer periphery of the lower bearing protrudes with a lower bearing rib, the radial protrusion of the pressure plate bearing groove has a pressure plate bearing groove rib, and after the lower bearing sleeve is provided with a fourth sealing ring, it is clamped on the pressure plate bearing groove using the lower bearing rib and the pressure plate bearing groove rib.

[0065] Embodiment three:

[0066] See Figure 8 and 9 The difference between this embodiment and the first embodiment is the structure to avoid the exchange of liquids in the first impeller chamber and the second impeller chamber. The shielded electric pump with a pump structure driven by each of the two ends of the motor shaft of this embodiment also includes an annular fifth sealing ring 830. The end surface of the end plate 160" of the pump body is concave to form a first bearing groove 161", and the upper bearing 361" is installed on the first bearing groove 161" after the fifth sealing ring 830 is sleeved. The shielded electric pump with a pump structure driven by each of the two ends of the motor shaft after this design can avoid mutual exchange when different temperatures or different liquids are respectively set in the first impeller chamber and the second impeller chamber, thereby increasing the use range of the centrifugal pump. Furthermore, the rotor assembly 300' also includes a plastic part 350' that is injection-molded and fixed on the rotating shaft 310. The end surface of the plastic part 350' facing the end plate 160" has several annular rotor convex ribs 351' protruding therefrom. The end surface of the end plate 160" facing the plastic part 350' has several annular pump casing convex ribs 140", and the rotor convex ribs 351' and the pump casing convex ribs 140" are staggered and inserted to form a labyrinth sealing structure. This design uses the gap of the labyrinth to further limit the exchange of liquids in the first impeller chamber and the second impeller chamber, thereby improving the sealing effect between the first impeller chamber and the second impeller chamber.

[0067] Embodiment 4:

[0068] See Figure 20 to Figure 22, the difference between this embodiment and the first embodiment is the structure of the third sealing ring and the connection structure between the third sealing ring and the end plate or the pressure plate. The shielded electric pump with a pump structure driven by each of the two ends of the motor shaft in this embodiment also includes a clamping member 170 for fixing and installing the third sealing ring 860'. The clamping member 170 includes a hollow cylindrical clamping member body 173, a hook 171 provided on the axial end surface of the clamping member body 173, a clamping member boss 172 protruding radially inward from the inner ring of the clamping member body 173, and a clamping member rib 174 protruding from the axial end surface of the clamping member body 173. The third sealing ring 860' includes a hollow cylindrical third sealing ring body 862', an outer sealing ring 863' provided on the outer periphery of the third sealing ring body 862', and a transition connector 864' connecting the two. An outer sealing ring groove 865' is axially provided on the outer sealing ring 863', and a clamping groove is provided on the end plate 160'' of the pump body. After the third sealing ring 860' is clamped on the clamping piece boss 172, the clamping piece 170 is clamped on the clamping groove of the end plate 160''. Of course, as other equivalent implementation examples, the pressure plate is provided with a pressure plate clamping groove on the axial end face facing the stator cavity side, and after the third sealing ring passes through the rotating shaft, the third sealing ring is clamped into the pressure plate clamping groove by the clamping piece.

[0069] The present invention is not limited to the above-mentioned embodiments. If various modifications or variations of the above-mentioned embodiments do not depart from the spirit and scope of the present invention, these modifications and variations belong to the claims and equivalent technical scope of the present invention, that is, the present invention also includes these modifications and variations.

Claims

1. A canned electric pump with a pump structure driven by each of the two ends of the motor shaft, comprising: A pump housing (100, 100´, 100´´, 100´´´), a rotor assembly (300, 300´), a first pump cover (600), a second pump cover (700) and a stator assembly (30), wherein an upper impeller (330) and a lower impeller (340) are fixed to two ends of a rotating shaft (310) of the rotor assembly, and the pump housing (100, 300´) are characterized in that the pump housing (100, 300´) and the first pump cover (600) are connected to the pump housing (100, The pump casing (100, 100´, 100´´, 100´´) is formed with a stator cavity (10) for accommodating a stator assembly and a tubular inner casing (110) with openings at both ends. The inner cavity of the inner casing (110) accommodates a rotor assembly (300, 300´). The pressure plate (200) is fixedly arranged at the other axial end of the pump casing and watertightly seals the stator cavity (10). The second pump cover (700) and the pressure plate ( The inner shell (110) and the pressure plate (200) are arranged to meet and cover each other to form a second impeller chamber (50) for accommodating the lower impeller (340); an annular first sealing ring (810) is arranged between the outer shell (120) of the pump casing and the pressure plate (200); an annular pressure plate groove (210) is arranged on the side of the pressure plate (200) facing the stator chamber; the inner shell (110) is inserted and installed in the pressure plate groove (210); a second sealing ring (820, 820´) is arranged between the inner shell (110) and the pressure plate (200); and the inner ring of the third sealing ring (860, 860´) has more than two radial protrusions that are in close contact with the stator chamber. The rotating shaft (310) has an annular third sealing ring rib (861, 861´); the upper bearing (361) is injection-molded and fixed on the annular end plate (160, 160´´´) of the pump housing, the third sealing ring (860, 860´) is located between the magnetic core (320) of the rotor assembly and the annular end plate (160, 160´´´), and is fixed on the annular end plate (160, 160´´´); or the lower bearing is injection-molded and fixed on the pressure plate, the third sealing ring is located between the magnetic core of the rotor assembly and the pressure plate, and is fixed on the pressure plate.

2. A canned electric pump with a pump structure driven by each of the two ends of the motor shaft, comprising: A pump housing (100, 100´, 100´´, 100´´´), a rotor assembly (300, 300´), a first pump cover (600), a second pump cover (700) and a stator assembly (30), wherein an upper impeller (330) and a lower impeller (340) are fixed to the two ends of the rotating shaft (310) of the rotor assembly, and the pump housing (100, 100´, 100´´), a rotor assembly (300, 300´), a first pump cover (600), a second pump cover (700) and a stator assembly (30), wherein the upper impeller (330) and the lower impeller (340) are fixed to the two ends of the rotating shaft (310) of the rotor assembly, and the pump housing (100, 100´, 100´´, 100´´) and the stator assembly (30) are characterized in that ... The first pump cover (600) and the pump housing (100, 100´, 100´´, 100´´) are joined at one axial end to form a first impeller chamber (40) for accommodating an upper impeller (330); the pump housing (100, 100´, 100´´, 100´´) is formed with a stator chamber (10) for accommodating a stator assembly and a tubular inner housing (110) with openings at both ends; the inner chamber of the inner housing (110) accommodates a rotor assembly. The pump housing comprises a plurality of components (300, 300'), the pressure plate (200) is fixedly mounted at the other axial end of the pump housing and watertightly seals the stator cavity (10), the second pump cover (700) and the pressure plate (200) are engaged with each other to form a second impeller cavity (50) for accommodating the lower impeller (340), the inner ring of the fourth sealing ring has more than two annular fourth sealing ring ribs (851) protruding radially inwardly and closely contacting the rotating shaft; the annular end plate (160') of the pump housing is provided with a concave bearing groove ( 166´), the bearing groove (166´) is provided with a raised upper bearing groove rib (167´) or a concave end plate groove in the radial direction, the upper bearing (361´) is sleeved with a fourth sealing ring (850) and is clamped on the bearing groove (166´); or, the axial end surface of the pressure plate is provided with a concave pressure plate bearing groove, the pressure plate bearing groove is provided with a raised pressure plate bearing groove rib or a concave pressure plate groove in the radial direction, the lower bearing is sleeved with a fourth sealing ring and is clamped on the pressure plate bearing groove.

3. A canned electric pump with a pump structure driven by each of the two ends of the motor shaft, comprising: A pump housing (100, 100´, 100´´, 100´´´), a rotor assembly (300, 300´), a first pump cover (600), a second pump cover (700) and a stator assembly (30), wherein an upper impeller (330) and a lower impeller (340) are fixed to two ends of a rotating shaft (310) of the rotor assembly, and the pump housing is characterized in that the pump housing further comprises a pressure plate (200), and further comprises an upper bearing (361´´) and a lower bearing (362´´) for the rotating shaft to pass through and install. and an annular fifth sealing ring (830); the first pump cover (600) and the pump housing (100, 100´, 100´´, 100´´´) meet and cover each other at one axial end to form a first impeller chamber (40) for accommodating an upper impeller (330); the pump housing (100, 100´, 100´´, 100´´´) is formed with a stator chamber (10) for accommodating a stator assembly and a tubular inner housing (110) with openings at both ends; the inner chamber of the inner housing (110) accommodates The rotor assembly (300, 300´), the pressure plate (200) is fixedly arranged at the other axial end of the pump housing and watertightly seals the stator cavity (10), the second pump cover (700) and the pressure plate (200) are matched to form a second impeller cavity (50) for accommodating the lower impeller (340), the annular end plate (160´´) of the pump housing is concave to form a first bearing groove (161´´), the upper bearing (361´´) is sleeved with a fifth sealing ring (830), and is installed at On the first bearing groove (161´´), the rotor assembly (300) further comprises a plastic part (350´) fixed on the rotating shaft (310) by injection molding, the end surface of the annular end plate of the plastic part facing the pump housing protrudes with a plurality of annular rotor convex ribs (351´), the end surface of the end plate facing the plastic part protrudes with a plurality of annular pump housing convex ribs (140´´), and the rotor convex ribs (351´) and the pump housing convex ribs (140´´) are staggered and inserted to form a labyrinth seal structure.

4. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 1, 2 or 3, characterized in that: The second sealing ring (820) is a hollow columnar structure with an annular groove.

5. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 1, 2 or 3, characterized in that: The axial single-side cross-section of the second sealing ring (820') is in an "L" shape, and the second sealing ring (820') is closely attached to the cylindrical surface of the pressure plate groove (210) and has a plurality of annular second sealing ring convex ribs (821').

6. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 1, 2 or 3, characterized in that: The pump housing also includes a control panel (400) and a side cover (500). The outer wall surface of the outer shell (120) of the pump housing protrudes outward to form a cylindrical peripheral edge (121). The side cover (500) is fixedly mounted on the peripheral edge (121) and is combined with the peripheral edge to form a mounting cavity (20) for mounting the control panel. A through hole (122) is provided on the outer wall surface to connect the stator cavity (10) and the mounting cavity (20).

7. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 6, characterized in that: It also includes a conductive rod (920), which passes through the through hole (122), one end of which is in contact with the iron core (31) on the stator assembly, and the other end of which is in conduction with the control board (400).

8. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 7, characterized in that: It also includes an annular elastic block (840) arranged between the pressing plate (200) and the iron core (31); the conductive rod (920) is provided with a protrusion (921) protruding toward the iron core; the annular elastic block (840) presses the conductive rod (920) and places the protrusion (921) close to the axial end surface of the iron core (31).

9. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 1, characterized in that: It also includes a clamping member (170) for fixing and installing a third sealing ring (860´), the clamping member including a hollow cylindrical clamping member body (173), a hook (171) provided on the axial end surface of the clamping member body (173), and a clamping member boss (172) protruding radially inward from the inner ring of the clamping member body (173), the third sealing ring (860´) is clamped to the clamping member boss (172), and the clamping member (170) is clamped to the end plate (160´´´) or the pressure plate (200).

10. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 9, characterized in that: The third sealing ring (860´) comprises a third sealing ring body (862´) in a hollow columnar shape, an outer sealing ring (863´) arranged on the outer periphery of the third sealing ring body (862´), and a transition connector (864´) connecting the two, the outer sealing ring (863´) is axially provided with an outer sealing ring groove (865´), the axial end surface of the clamping part body (173) protrudes a clamping part convex rib (174), and the outer sealing ring groove (865´) is sleeved on the clamping part convex rib (174).

11. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 1, 2 or 3, characterized in that: The axial protrusion of the upper bearing (361, 361´, 361´´) is exposed on the annular end plate (160, 160´, 160´´) of the pump housing, and the axial protrusion of the lower bearing (362, 362´, 362´´) is exposed on the axial end surface of the pressure plate (200).

12. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 11, characterized in that: It also includes an impeller insert (370) injection-molded on each of the upper impeller and the lower impeller, wherein the impeller insert (370) protrudes axially from the outer end surface of the shaft disc in which the impeller is embedded.

13. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 12, characterized in that: An axial hole (311) and a shaft boss (312) for assembling an upper impeller (330) and a lower impeller (340) are respectively provided at both ends of the shaft (310); a radially symmetrical flat position is provided on the shaft boss (312); and an insert hole (371) with a flat position groove for the shaft (310) to be inserted and assembled is provided on the impeller insert (370).

14. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 1, 2 or 3, characterized in that: A pressure plate through hole (220) is provided on the axial end surface of the pressure plate (200), and the pressure plate through hole connects the second impeller cavity (50) with the rotor cavity surrounded by the pressure plate and the inner shell and accommodating the rotor assembly.

15. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 1, 2 or 3, characterized in that: The upper impeller and the lower impeller are co-directional impellers.

16. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 15, characterized in that: The outer diameter of the upper impeller (330) is not equal to the outer diameter of the lower impeller (340).

17. A canned motor pump with a pump structure driven by each of the two ends of the motor shaft according to claim 6, characterized in that: A side plate (510) with a mounting hole protrudes from the radial end surface of the side cover (500).

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