Internal circulation structure for shielded pump

Abstract

The present application relates to the technical field of shielded pump equipment, and discloses an internal circulation structure for a shielded pump, comprising: a machine base, a rotor assembly and a pump head, wherein a stator shielding sleeve is provided in the machine base, a boss is provided on the inner wall of the pump head, and the lower bearing seat is overlapped on the boss. When the machine base and the pump head are closed, the lower bearing seat is pressed against the boss by the machine base, and a throttling channel is formed between the lower bearing seat and the machine base, and between the lower bearing seat and the stator shielding sleeve. The throttling channel increases the resistance to liquid flow. The internal circulation structure for a shielded pump increases the resistance to liquid flow through the throttling channel, thereby limiting the flow rate of the liquid passing through, so that the proportion of liquid participating in the internal circulation is appropriate. Secondly, the proportion of liquid participating in the internal circulation is controlled by blocking the groove with a sealing plate. The amount of liquid participating in the internal circulation can be flexibly adjusted in different scenarios, so that the amount of liquid participating in the internal circulation is in the optimal proportion, thereby ensuring the service life and efficiency of the shielded pump.

Description

Technical Field

[0001] The present application relates to the technical field of shielded pump equipment, and in particular to an internal circulation structure for a shielded pump. Background Art

[0002] When the shielded pump is working, the liquid is divided into two parts in the high-pressure area. Most of it flows out directly, and a small part flows through the shielding sleeve through the flow channel and flows back from the rotating shaft to the low-pressure area, lubricating and dissipating heat for the shielded pump in the form of internal circulation.

[0003] Existing canned motor pumps feature a through-hole in the bearing housing, allowing a small portion of the liquid in the high-pressure area to enter the shield housing through the through-hole. Generally, to control the proportion of liquid participating in the internal circulation, the through-hole diameter should not be too large. If the pumped liquid precipitates, cokes, or forms a gel, it may clog the through-hole, affecting the cooling and lubrication of the pump. Furthermore, the cost of opening a hole in the bearing or bearing housing is high.

[0004] Secondly, since the diameter of the connecting hole is fixed, and the shielded pump has different uses, the physical properties and states of the medium are different. The same cross-sectional area just makes the amount of liquid participating in the internal circulation in the optimal state in some scenarios, but it may be excessive or insufficient in other scenarios. If the amount of liquid participating in the internal circulation is excessive, it will lead to large energy loss and reduced head. If the amount participating in the internal circulation is insufficient, the lubrication and heat dissipation requirements will not be met. Summary of the Invention

[0005] The present application proposes an internal circulation structure for a shielded pump, which increases the resistance to liquid flow through a throttling channel, thereby limiting the flow rate of the liquid passing through, making the proportion of liquid participating in the internal circulation appropriate, and solving the problems in the background technology.

[0006] In order to achieve the above-mentioned purpose, the present application adopts the following technical solution: an internal circulation structure for a shielded pump, comprising: a machine base, a rotor assembly and a pump head, a stator shielding sleeve is provided in the machine base, a stator assembly is provided in the inner cavity of the stator shielding sleeve, the rotor assembly is connected to a shaft, the shaft passes through the rotor assembly, both ends of the shaft are connected to bearings, one side of the shaft is movably connected to the upper bearing seat through the bearing, the upper bearing seat is fixedly connected to the machine base, the other side of the shaft is movably connected to the lower bearing seat through the bearing, the shaft extends into the pump head, and the shaft is located at the part of the pump head. The shaft is connected to the pump head and is provided with an impeller. When the impeller rotates, a high-pressure area and a low-pressure area are formed in the pump head. An axial hole is provided in the shaft, which is connected to the low-pressure area. An open groove is provided at the other end of the shaft. The liquid enters the open groove from the bottom of the machine base and flows back to the low-pressure area from the axial hole. A boss is provided on the inner wall of the pump head, and the lower bearing seat is overlapped on the boss. When the machine base and the pump head are closed, the lower bearing seat is pressed against the boss by the machine base. A throttling channel is formed between the lower bearing seat and the machine base, as well as between the lower bearing seat and the stator shield sleeve. The throttling channel increases the resistance to liquid flow.

[0007] Furthermore, a convex point is provided between the lower bearing seat and the boss, which separates the lower bearing seat and the boss to form gap one. A gasket is provided between the lower bearing seat and the stator shielding sleeve, which separates the lower bearing seat and the stator shielding sleeve to form gap two. A connecting groove is constructed between the inner wall of the pump head and the outer wall of the stator shielding sleeve, and gap one, gap two and the connecting groove constitute a throttling channel.

[0008] Furthermore, the convex point is a protrusion on the lower bearing seat, the lower bearing seat is provided with an annular groove close to the stator shielding sleeve, and the lower bearing seat is made by a stamping process.

[0009] Furthermore, the outer circle of the lower bearing seat is provided with a groove, the inner wall of the pump head is complete and smooth, the groove and the inner side wall of the pump head form a connecting groove, the inner wall of the gasket is provided with a gasket groove, the gasket is pressed on the outer circle of the lower bearing seat, and the groove is aligned with the gasket groove.

[0010] Furthermore, a protrusion is provided on the inner wall of the pump head, and a pump cover groove is formed between the two protrusions. The lower bearing seat overlaps the boss, and the side wall of the lower bearing seat is attached to the end face of the protrusion. The outer circle of the lower bearing seat remains intact, and the pump cover groove and the outer circle of the pump head constitute a connecting groove.

[0011] Furthermore, it also includes a positioning ring, the inner wall of the positioning ring is fixedly connected with a sealing piece corresponding to the groove one by one, the sealing piece is attached to the lower bearing seat and blocks the groove, the positioning ring is attached to the inner wall of the pump head, the top of the pump head is provided with a float cavity, the float cavity is connected with the interior of the pump head through a connecting groove, the positioning ring is fixedly connected with a float through a connecting strip, the float is located in the float cavity, the float drives the positioning ring to rotate under the action of gravity or buoyancy, and when the float rises to the highest point under the action of buoyancy, the blocking of the groove is minimized.

[0012] Furthermore, a telescopic bag is provided on the float cavity, and the telescopic bag is connected to the high-pressure area through a pipeline. The high pressure causes the telescopic bag to expand and stretch, pushing the float to move. An adjustment component is provided on the side of the float facing away from the telescopic bag, and the adjustment component has multiple groups of protrusions that can extend to block the float.

[0013] Furthermore, the positioning ring has two parts, which form a ring. The positioning ring or the blocking piece is connected to the inner ring via a connecting piece, which is connected to the inner ring via bolts. The thickness of the connecting piece is less than the height of the protrusion.

[0014] Beneficial effects of the present invention:

[0015] The present application provides an internal circulation structure for a shielded pump, which increases the resistance to liquid flow through a throttling channel, thereby limiting the flow rate of the liquid passing through, so that the proportion of liquid participating in the internal circulation is appropriate. Compared with the connecting hole, the flow area of ​​the throttling channel is larger and not easy to be blocked. On the other hand, the shape formed by stamping the lower bearing seat cooperates with the inner wall of the pump head and the end face of the stator shielding sleeve to form a throttling channel, and the process is relatively simple.

[0016] Secondly, the proportion of liquid participating in the internal circulation is controlled by blocking the groove with the sealing piece. The amount of liquid participating in the internal circulation can be flexibly adjusted in different scenarios, so that the amount of liquid participating in the internal circulation is in the optimal proportion, ensuring the service life and efficiency of the shielded pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which constitute a part of the specification, illustrate the embodiments disclosed in the present application and, together with the description, serve to explain the principles of the embodiments disclosed in the present application.

[0018] The embodiments disclosed in this application may be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:

[0019] Figure 1 is a cross-sectional view of the present invention;

[0020] Figure 2 This is a schematic diagram of a first embodiment of the lower bearing seat in the present invention;

[0021] Figure 3 is a schematic diagram of the liner of the present invention;

[0022] Figure 4 This is a schematic diagram of a second embodiment of the lower bearing seat in the present invention;

[0023] Figure 5 This is a schematic diagram of a second embodiment of the pump head of the present invention;

[0024] Figure 6 It is a partial exploded view of the present invention;

[0025] Figure 7 It is a front view of the positioning ring in the present invention;

[0026] Figure 8 It is a schematic diagram of the three-dimensional structure of the positioning ring in the present invention.

[0027] In the figure: 1. base; 2. pump head; 3. stator assembly; 4. rotor assembly; 5. stator shield; 6. bearing; 7. upper bearing seat; 8. impeller; 9. high-pressure area; 10. shaft; 11. low-pressure area; 12. lower bearing seat; 13. boss; 14. gasket; 15. bump; 16. throttling channel; 17. shaft hole; 18. ring groove; 19. groove; 20. gasket groove; 21. protrusion; 22. pump cover groove; 23. positioning ring; 24. positioning groove; 25. sealing piece; 26. float; 27. float cavity; 28. telescopic bag; 29. ​​adjustment assembly; 30. connecting groove; 31. inner ring; 32. connecting piece. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0029] Example 1

[0030] See also Figure 1 and Figure 2, a shielded pump internal circulation structure, including a base 1 and a pump head 2, the base 1 and the pump head 2 are fixed by bolts, a stator assembly 3 and a rotor assembly 4 are arranged in the base 1, the inner wall of the base 1 is provided with a stator shielding sleeve 5, the stator assembly 3 is arranged in the stator shielding sleeve 5, the rotor assembly 4 is fixedly connected with a shaft 10, both ends of the shaft 10 are provided with bearings 6, the bottom of the base 1 is provided with an upper bearing seat 7, the shaft 10 is movably connected to the upper bearing seat 7 through the bearing 6, the shaft 10 is provided with an open groove near the upper bearing seat 7, the shaft of the shaft 10 The line is provided with an axial hole 17, and the open groove is connected to the axial hole 17. The other end of the shaft 10 is movably connected to the lower bearing seat 12 through the bearing 6. The inner wall of the pump head 2 is provided with a boss 13. The lower bearing seat 12 is overlapped on the boss 13. The stator shield sleeve 5 presses the lower bearing seat 12 on the boss 13 through the gasket 14. The outer circle of the lower bearing seat 12 is pressed against the inner wall of the pump head 2 to achieve radial and axial positioning of the lower bearing seat 12, ensuring the stability of the rotor assembly 4 during rotation. The shaft 10 extends to the inner cavity of the pump head 2. The shaft 10 is connected to the impeller 8 The impeller 8 is located in the inner cavity of the pump head 2. When the impeller 8 rotates, the inner cavity of the pump head 2 forms a low-pressure area 11 and a high-pressure area 9. The lower bearing seat 12 is located on one side of the high-pressure area 9. The high-pressure area 9 is connected to the output pipeline, and the low-pressure area 11 is connected to the input pipeline. The shaft 10 extends into the low-pressure area 11. A throttling channel 16 is formed between the lower bearing seat 12 and the machine base 1 and between the lower bearing seat 12 and the stator shield 5. The throttling channel 16 increases the resistance to liquid flow and limits the proportion of liquid participating in the internal circulation. For example, the throttling channel The cross-sectional area of ​​the channel 16 can also be designed as a throttling channel. In this embodiment, a protrusion 15 is provided between the lower bearing seat 12 and the boss 13, and the protrusion 15 separates the lower bearing seat 12 and the boss 13 to form a gap one. A gasket 14 is provided between the lower bearing seat 12 and the stator shielding sleeve 5, and the gasket 14 separates the lower bearing seat 12 and the stator shielding sleeve 5 to form a gap two. A connecting groove is constructed between the inner wall of the pump head 2 and the outer wall of the stator shielding sleeve 5. The gap one, the gap two and the connecting groove constitute the throttling channel 16.

[0031] When the shielded pump is working, the impeller 8 rotates to form a high-pressure zone 9 and a low-pressure zone 11. The low-pressure zone 11 draws in liquid and flows into the high-pressure zone 9. The liquid in the high-pressure zone 9 is divided into two parts. Most of the liquid flows out from the output pipeline, and a small part flows through the gap 1 between the stator shielding sleeve 5 and the boss 13, and enters the gap 2 between the stator shielding sleeve 5 and the lower bearing seat 12 through the connecting groove. After flowing out of the gap 2, the liquid passes through the gap between the stator shielding sleeve 5 and the rotor assembly 4, and then enters the shaft hole 17 through the open groove, and finally flows back to the low-pressure zone 11. Because the cross-section of the liquid is narrow and the direction changes greatly when it flows through the gap 1, the connecting groove and the gap 2, the pressure loss of the liquid when it flows through the throttling channel 16 is relatively large, thereby controlling the proportion of the liquid participating in the internal circulation and making the liquid flow participating in the internal circulation more reasonable.

[0032] See also Figure 2 and Figure 6 The convex point 15 is a protrusion on the lower bearing seat 12. The lower bearing seat 12 is provided with an annular groove 18 close to the stator shield sleeve 5. The space between the annular groove 18 and the stator shield sleeve 5 becomes narrow and increases a turning point, thereby increasing the resistance to liquid flow. The lower bearing seat 12 is made by stamping, and the annular groove 18, the groove 19 and the convex point 15 are formed by stamping.

[0033] There are two implementation methods for the connecting groove. The first one is shown in Figure 2 and Figure 3 The outer circle of the lower bearing seat 12 is provided with a groove 19, the inner wall of the pump head 2 is complete and smooth, the groove 19 and the inner side wall of the pump head 2 form a connecting groove, the inner wall of the liner 14 is provided with a gasket groove 20, the gasket 14 is pressed on the outer circle of the lower bearing seat 12, the groove 19 is aligned with the gasket groove 20, and the liquid enters the gap 2 through the groove 19 and the gasket groove 20.

[0034] Second, see Figure 4 and Figure 5 The inner wall of the pump head 2 is provided with a protrusion 21, and a pump cover groove 22 is formed between the two protrusions 21. The lower bearing seat 12 overlaps the boss 13, and the side wall of the lower bearing seat 12 is attached to the end face of the protrusion 21. The thickness of the protrusion 21 is slightly smaller than the lower bearing seat 12, ensuring that the gasket 14 can press the lower bearing seat 12, and the outer circle of the lower bearing seat 12 remains intact. The pump cover groove 22 and the outer circle of the pump head 2 constitute a connecting groove.

[0035] Example 2

[0036] The second embodiment can be implemented independently of the first embodiment, or can be implemented based on the first embodiment. Figure 7 , also includes a positioning ring 23, the inner wall of the positioning ring 23 is fixedly connected with a sealing piece 25 corresponding to the groove 19, the sealing piece 25 is attached to the lower bearing seat 12 and blocks the groove 19, changing the flow area of ​​the groove 19 and increasing the flow resistance, the positioning ring 23 is attached to the inner wall of the pump head 2, the sealing piece 25 is located between the lower bearing seat 12 and the boss 13, and a float cavity 27 is provided on the top of the pump head 2, and the float cavity 27 is connected with the interior of the pump head 2 through the connecting groove 30. The positioning ring 23 is fixedly connected to a float 26 through a connecting strip, and the float 26 is located in the float cavity 27. The float 26 drives the positioning ring 23 to rotate under the action of gravity or buoyancy. When the float 26 rises to the highest point under the action of buoyancy, the obstruction of the groove 19 is minimized. The highest point of the float cavity 27 is provided with an exhaust port. Before the shielded pump is started, the exhaust port is opened and water is poured in. The gas is discharged from the telescopic bag 28. The water filling port is located on the machine base 1. Figure 1The water filling port is omitted, and a blocking structure is provided in the float cavity 27 to prevent the float 26 from reaching the highest point, and it is always biased to one side. In this way, when the shielding pump is not full of water, the float 26 can rotate under gravity. The float cavity 27 is provided with an observation window corresponding to the highest position of the float 26. By observing whether the float 26 reaches the highest position, it can be judged whether the shielding pump is full of water. On the other hand, by adjusting the position of the float 26, the blocking range of the sealing piece 25 on the groove 19 is adjusted, and the amount of liquid participating in the internal circulation is adjusted.

[0037] A telescopic bag 28 is provided on the float cavity 27, and the telescopic bag 28 is connected to the high-pressure area 9 through a pipeline. The high pressure causes the telescopic bag 28 to expand and stretch, pushing the float 26 to move. An adjustment component 29 is provided on the side of the float 26 facing away from the telescopic bag 28. The adjustment component 29 has multiple groups of protrusions, which will block the movement of the float 26 when triggered. The adjustment component 29 can be automatically controlled or manually controlled. Manual control is adopted in this embodiment. The adjustment component 29 has multiple buttons. When pressed, the corresponding protrusions move to block the movement of the float 26. The telescopic bag 28 is elastic. When the pump stops running and the high pressure disappears, the telescopic bag 28 retracts.

[0038] The positioning ring 23 has two parts, and the two parts form a ring. The positioning ring 23 or the sealing piece 25 is connected to the inner ring 31 through a connecting piece 32. The connecting piece 32 is connected to the inner ring 31 by bolts. The thickness of the connecting piece 32 is less than the height of the protrusion 15. The float 26 is snap-connected with the connecting strip. The connecting strip is fixedly connected to one of the parts. The connecting piece 32 passes through the gap between the boss 13 and the lower bearing seat 12 and is connected to the positioning ring 23 or the sealing piece 25. For ease of assembly, the two parts are first placed in the positioning groove 24 respectively, the connecting strip passes through the connecting groove 30, the float 26 is installed on the connecting strip, and then the two parts are connected to the inner ring 31. Tighten the bolts so that the two parts form a whole.

Claims

1. An internal circulation structure for a canned motor pump, comprising: A machine base (1), wherein a stator shielding sleeve (5) is provided in the machine base (1), and a stator assembly (3) is provided in an inner cavity of the stator shielding sleeve (5); A rotor assembly (4), wherein the rotor assembly (4) is connected to a shaft (10), the shaft (10) passes through the rotor assembly (4), both ends of the shaft (10) are connected to bearings (6), one side of the shaft (10) is movably connected to an upper bearing seat (7) via the bearing (6), the upper bearing seat (7) is fixedly connected to the machine base (1), and the other side of the shaft (10) is movably connected to a lower bearing seat (12) via the bearing (6); A pump head (2), wherein the shaft (10) extends into the pump head (2), and the portion of the shaft (10) located in the pump head (2) is connected to an impeller (8), and when the impeller (8) rotates, a high-pressure area (9) and a low-pressure area (11) are formed in the pump head (2), and an axial hole (17) is provided in the shaft (10), and the axial hole (17) is communicated with the low-pressure area (11), and an open groove is provided at the other end of the shaft (10), and liquid enters the open groove from the bottom of the upper bearing seat (7) and flows back to the low-pressure area (11) from the axial hole (17), and a boss (13) is provided on the inner wall of the pump head (2), and the lower bearing seat (12) is overlapped on the boss (13), and when the machine base (1) and the pump head (2) are closed, the lower bearing seat (12) is pressed against the boss (13) by the machine base (1); Its characteristics are: A throttling channel (16) is formed between the lower bearing seat (12) and the machine base (1) and between the lower bearing seat (12) and the stator shielding sleeve (5), and the throttling channel (16) increases the resistance to liquid flow; A convex point (15) is provided between the lower bearing seat (12) and the boss (13), and the convex point (15) separates the lower bearing seat (12) and the boss (13) to form a gap one. A gasket (14) is provided between the lower bearing seat (12) and the stator shielding sleeve (5), and the gasket (14) separates the lower bearing seat (12) and the stator shielding sleeve (5) to form a gap two. A connecting groove is constructed between the inner wall of the pump head (2) and the outer wall of the stator shielding sleeve (5), and the gap one, gap two and the connecting groove constitute a throttling channel (16).

2. The internal circulation structure for a canned motor pump according to claim 1, characterized in that: The convex point (15) is a protrusion on the lower bearing seat (12), and the lower bearing seat (12) is provided with an annular groove (18) close to the stator shielding sleeve (5), and the lower bearing seat (12) is made by a stamping process.

3. The internal circulation structure for a canned motor pump according to claim 2, characterized in that: The outer circle of the lower bearing seat (12) is provided with a groove (19), the inner wall of the pump head (2) is complete and smooth, the groove (19) and the inner side wall of the pump head (2) form a connecting groove, the inner wall of the liner (14) is provided with a liner groove (20), the liner (14) is pressed on the outer circle of the lower bearing seat (12), and the groove (19) is aligned with the liner groove (20).

4. The internal circulation structure for a canned motor pump according to claim 3, characterized in that: The inner wall of the pump head (2) is provided with a protrusion (21), and a pump cover groove (22) is formed between the two protrusions (21). The lower bearing seat (12) is overlapped on the boss (13), and the side wall of the lower bearing seat (12) is attached to the end surface of the protrusion (21). The outer circle of the lower bearing seat (12) remains intact, and the pump cover groove (22) and the outer circle of the pump head (2) form a connecting groove.

5. The internal circulation structure for a canned motor pump according to claim 4, characterized in that: The pump (2) further comprises a positioning ring (23), the inner wall of which is fixedly connected with a blocking piece (25) corresponding to the groove (19), the blocking piece (25) being close to the lower bearing seat (12) and blocking the groove (19), the positioning ring (23) being close to the inner wall of the pump head (2), the top of the pump head (2) being provided with a float cavity (27), the float cavity (27) being connected with the interior of the pump head (2) through a connecting groove (30), the positioning ring (23) being fixedly connected with a float (26) through a connecting strip, the float (26) being located in the float cavity (27), the float (26) driving the positioning ring (23) to rotate under the action of gravity or buoyancy, and the blocking of the groove (19) by the float (26) being minimized when the float (26) rises to the highest point under the action of buoyancy.

6. The internal circulation structure for a canned motor pump according to claim 5, characterized in that: A telescopic bag (28) is provided on the float cavity (27), and the telescopic bag (28) is connected to the high-pressure area (9) through a pipeline. The high pressure causes the telescopic bag (28) to expand and extend, pushing the float (26) to move. An adjustment component (29) is provided on the side of the float (26) facing away from the telescopic bag (28). The adjustment component (29) has multiple groups of protrusions that can extend to block the float (26).

7. The internal circulation structure for a canned motor pump according to claim 5, characterized in that: The positioning ring (23) has two parts, which form a ring. The positioning ring (23) or the blocking piece (25) is connected to the inner ring (31) via a connecting piece (32). The connecting piece (32) is connected to the inner ring (31) via a bolt. The thickness of the connecting piece (32) is less than the height of the protrusion (15).

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