Permanent magnet direct drive pump with sealing structure

Abstract

The invention discloses a permanent magnet direct drive pump with a sealing structure, and belongs to the field of permanent magnet direct drive pumps, the permanent magnet direct drive pump comprises a front cover, an impeller, a magnetic bag, a pump shaft, a bearing, a rear cover, a power supply part and a plurality of sealing rings, the front cover and the power supply part are provided with inner cavities, the inner cavities of the front cover and the power supply part are opposite, and the outer end of the front cover is connected with the outer end of the power supply part through a bolt; the pump shaft penetrates through the impeller and the magnetic bag, the two ends of the pump shaft are inserted into the front cover and the rear cover respectively, the pump shaft is sleeved with the bearing, the bearing is fixed between an inner hole of the magnetic bag and the pump shaft, and the exterior of the rear cover cylinder is installed in a power supply part cavity. A plurality of sealing rings are respectively sleeved at the joint of the rear cover and the front cover and inside the power supply part, the power supply part is provided with an excitation winding and a junction box, the power supply is electrically connected with the excitation winding through a wiring terminal in the junction box, and the excitation winding generates an electromagnetic field after being electrified to interact with the rotor in the magnetic bag to drive the rotor to rotate to enable the impeller to work.

Description

Technical Field

[0001] The present invention belongs to the technical field of permanent magnet direct drive pumps, and more specifically, relates to a permanent magnet direct drive pump with a sealing structure. Background Art

[0002] A permanent magnet direct drive pump is a pump that is directly driven by a permanent magnet synchronous motor. The permanent magnet direct drive pump uses a permanent magnet synchronous motor as a driver. The permanent magnet in the motor generates a magnetic field, and the current in the stator coil inside the motor generates an electromagnetic field, so that force and torque occur between the permanent magnet and the electromagnetic field. When the motor drives the external magnet to rotate, the magnetic field can pass through the air gap and non-magnetic materials, driving the permanent magnet structure connected to the impeller to rotate synchronously, realizing contactless transmission of power and converting dynamic seals into static seals. It is widely used in key equipment for conveying flammable, explosive, highly toxic, high-risk media, and precious liquids, but in During operation, the rotation of the impeller will inevitably swing the liquid to cause leakage and sticking. Existing magnetic pumps usually install rubber sealing rings at the connection end of the permanent magnet structure and the impeller. In the process of conveying liquid, improper operation or incorrect material selection by the customer may cause liquid leakage from the rear shell, resulting in damage to the excitation winding. When leakage occurs, only one layer of protection is formed at the connection end of the permanent magnet structure and the impeller. When the conveyed liquid has leaked out of the permanent magnet structure, the excitation winding in the drive cannot be protected, resulting in a reduction in the service life of the permanent magnet direct-drive pump or even damage to it. Therefore, a permanent magnet direct-drive pump with a sealing structure with multiple protections is required. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a permanent magnet direct drive pump with a sealing structure, which can meet the requirement of the permanent magnet direct drive pump having a sealing structure with multiple protections.

[0004] The present invention discloses a permanent magnet direct-drive pump with a sealing structure, comprising a front cover, an impeller, a magnetic capsule, a pump shaft, a bearing, a rear cover, a power supply part and a plurality of sealing rings. The front cover and the power supply part are both provided with an inner cavity and the inner cavities of the two are opposite to each other. The outer end of the front cover is connected to the outer end of the power supply part by bolts. One end of the impeller is sleeved in the front cover cavity, and the other end is fixedly connected to one end of the magnetic capsule. The rear cover is set in a cylindrical shape, and the other end of the magnetic capsule is sleeved in the interior of the rear cover cylinder. The pump shaft passes through the impeller and the magnetic capsule, and the two ends of the pump shaft are respectively inserted into the interior of the front cover and the rear cover. The bearing is sleeved outside the pump shaft and is located between the magnetic capsule and the pump shaft. The outside of the rear cover cylinder is installed in the power supply part cavity. A plurality of sealing rings are respectively sleeved on the connection between the rear cover and the front cover and the interior of the power supply part. A plurality of permanent magnet rotors are integrated on the magnetic capsule. When the magnetic capsule rotates, the permanent magnet rotor generates a fixed magnetic field.

[0005] As a further improvement of the present invention, the power supply part includes a power supply shell, an excitation winding, and a motor partition. The inner side of the power supply shell is fixedly connected to the outer side of the motor partition. A junction box is provided at the end of the motor partition away from the power supply shell. The excitation winding is installed in the inner cavity of the power supply shell and one end is in contact with the end face of the motor partition. The external power supply is electrically connected to the excitation winding through the junction box. When the excitation winding is energized, an electromagnetic field is generated. The electromagnetic field interacts with the permanent magnet on the magnetic capsule, thereby driving the magnetic capsule to rotate. One end of the motor partition close to the excitation winding is in contact with the back cover, the outer side of the excitation winding is coated with a sealing insulation layer, and the inside and outside of the excitation winding are filled with epoxy resin glue to prevent damage to the excitation winding after leakage, thereby improving safety.

[0006] As a further improvement of the present invention, a convex edge is provided at one end where the rear cover is connected to the front cover, and a sealing ring is sleeved on the convex edge to block the liquid thrown out by the rotation of the impeller to prevent leakage; a sealing ring is sleeved on the end where the excitation winding is close to the power supply housing, and two sealing steps are provided on the end where the motor partition is connected to the excitation winding. The sealing ring is sleeved on any one of the sealing steps to form a second barrier to the leaked liquid, and when the leaked liquid has penetrated into the rear cover, the leaked liquid is prevented from penetrating into the excitation winding, and the excitation winding is prevented from being contaminated. The sealing ring meets the sealing requirements while ensuring the connection fit between the rear cover and the power supply part, and avoids the sealing ring affecting the connection stability between the rear cover and the power supply part.

[0007] As a further improvement of the present invention, a liquid inlet and a liquid outlet are provided on the outside of the front cover, the liquid inlet is provided in the central area of ​​the front cover, an axis frame is provided in the inner cavity of the front cover, one end of the axis frame is fixedly connected to the liquid inlet, and the other end is provided with a slot matching the pump shaft, a slot matching the pump shaft is provided at the bottom of the rear cover cylinder, and both ends of the pump shaft are respectively inserted into the slots of the axis frame and the rear cover, thereby strengthening the connection strength between the pump shaft and the front cover and the rear cover.

[0008] As a further improvement of the present invention, the inner cavity of the front cover is provided with a plurality of gradually expanding concave rings to increase the flow space of the inner cavity of the front cover and improve the head of the permanent magnet direct-drive pump; three extended guide plates are provided on the shaft frame, the guide plates are connected to the inner wall of the liquid inlet and the guide plates are symmetrically distributed with the shaft frame slot as the center, thereby ensuring the connection strength while increasing the flow space of the liquid inlet and improving the head of the permanent magnet direct-drive pump.

[0009] As a further improvement of the present invention, it also includes a thrust bearing and a rear thrust ring. The thrust bearing includes a front thrust ring and an interface ring. The front thrust ring is coupled to the interface ring. The front thrust ring is installed on a concave ring in the inner cavity of the front cover close to the liquid inlet. The interface ring is installed at one end of the impeller close to the front cover to control the vertical and horizontal accuracy of the excitation winding and the magnetic capsule to form a complete electromagnetic field. The rear thrust ring is sleeved on the pump shaft and located at the connection between the magnetic capsule and the rear cover to improve the stability of the permanent magnet direct drive pump.

[0010] Compared with the prior art, the beneficial effects of the present invention are: the sealing ring is sleeved on the convex edge connecting the rear cover and the front cover to prevent liquid leakage; the sealing ring is also sleeved on the connection between the two ends of the excitation winding to form a second line of protection, to prevent the leakage from penetrating into the excitation winding when the leakage has penetrated into the rear cover, and to prevent the excitation winding from being contaminated; the sealing ring is sleeved on the sealing step, to meet the sealing requirements while ensuring the connection fit between the rear cover and the power supply part, to prevent the sealing ring from affecting the connection stability between the rear cover and the power supply part; the outer side of the excitation winding is coated with a sealing insulation layer, and the excitation winding is filled with epoxy resin glue to prevent the excitation winding from being damaged after leakage, to protect the excitation winding coil and the junction box from being contaminated, and to improve safety; the inner cavity of the front cover is provided with a plurality of concave rings that expand step by step, to increase the flow space in the inner cavity of the front cover, and to increase the head of the permanent magnet direct drive pump; a thrust bearing is provided at the connection between the impeller and the front cover to control the axial clearance of the pump shaft and reduce the impact on the pump shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a schematic diagram of the explosion structure of the present invention; Figure 3 It is a schematic diagram of the explosion structure of the power supply part of the present invention; Figure 4 It is a front cross-sectional schematic diagram of the present invention; Figure 5 It is a front view and cross-sectional schematic diagram of the impeller pump shaft connection of the present invention; Figure 6 It is a front cross-sectional schematic diagram of the power supply unit of the present invention; Figure 7 It is a schematic diagram of the structure inside the front cover cavity of the present invention.

[0012] Description of the numbers in the figure: Front cover 1; liquid inlet 11; liquid outlet 12; shaft frame 13; guide plate 131; concave ring 14; impeller 2; magnetic capsule 3; pump shaft 4; bearing 5; rear cover 6; flange 61; power supply part 7; power supply housing 71; excitation winding 72; motor partition 73; terminal box 731; sealing step 732; sealing ring 8; thrust bearing 9; front thrust ring 91; interface ring 92; rear thrust ring 93. DETAILED DESCRIPTION

[0013] Specific embodiment 1: Please refer to Figure 1-Figure 7The present invention relates to a permanent magnet direct drive pump with a sealing structure, comprising a front cover 1, an impeller 2, a magnetic capsule 3, a pump shaft 4, a bearing 5, a rear cover 6 and a power supply part 7. The front cover 1 and the power supply part 7 are both provided with an inner cavity and the inner cavities of the two are opposite to each other. The outer end of the front cover 1 is connected with the outer end of the power supply part 7 by bolts. One end of the impeller 2 is sleeved in the cavity of the front cover 1, and the other end is fixedly connected to one end of the magnetic capsule 3. The rear cover 6 is set to be cylindrical, and the other end of the magnetic capsule 3 is sleeved inside the cylinder of the rear cover 6. The pump shaft 4 passes through the impeller 2 and the magnetic capsule 3, and the two ends of the pump shaft 4 are respectively inserted into the front cover 1 and the rear cover 6. The bearing 5 is sleeved outside the pump shaft 4 and is located between the inner hole of the magnetic capsule 3 and the pump shaft 4. The outer side of the rear cover 6 cylinder is installed in the cavity of the power supply part 7. A plurality of permanent magnet rotors are integrated on the magnetic capsule 3. When rotating, the permanent magnet rotors generate a fixed magnetic field.

[0014] In a further embodiment, Figure 3 As shown, the power supply part 7 includes a power supply shell 71, an excitation winding 72, and a motor partition 73. The inner side of the power supply shell 71 is fixedly connected to the outer side of the motor partition 73. A terminal box 731 is provided at one end of the motor partition 73 away from the power supply shell 71. The excitation winding 72 is installed in the inner cavity of the power supply shell 71 and one end is attached to the end face of the motor partition 73. The excitation winding 72 is electrically connected to the terminal box 731. One end of the motor partition 73 close to the excitation winding 72 is attached to the back cover 6. The external power supply is electrically connected to the excitation winding 72 through the terminal in the terminal box 731. The excitation winding 72 generates an electromagnetic field, and the electromagnetic field interacts with the permanent magnet on the magnetic capsule 3, thereby driving the magnetic capsule 3 to rotate. The excitation winding 72 is a tin steel sheet enameled wire winding. The outer side of the excitation winding 72 is coated with a sealing insulation layer. The inside and outside of the excitation winding 72 are filled with epoxy resin glue to prevent the excitation winding 72 from being damaged after leakage, thereby improving safety.

[0015] In a further embodiment, Figure 4 and Figure 6 As shown, it also includes several sealing rings 8. The end where the rear cover 6 is connected to the front cover 1 is provided with a convex edge 61, and a sealing ring 8 is sleeved on the convex edge 61; the end where the excitation winding 72 is close to the power supply shell 71 is sleeved with a sealing ring, and the end where the motor partition 73 is connected to the excitation winding 72 is provided with two sealing steps 732. The sealing ring 8 is sleeved on any one of the sealing steps 732 to prevent the liquid in the permanent magnet direct drive pump from flowing into the power supply part 7 and causing damage to the pump body.

[0016] In a further embodiment, Figure 4 As shown, a liquid inlet 11 and a liquid outlet 12 are provided on the outside of the front cover 1, the liquid inlet 11 is provided in the central area of ​​the front cover 1, an axis frame 13 is provided in the inner cavity of the front cover 1, one end of the axis frame 13 is fixedly connected to the liquid inlet 11, and the other end is provided with a slot matching the pump shaft 4, a slot matching the pump shaft 4 is provided at the bottom of the inner tube of the rear cover 6, and the two ends of the pump shaft 4 are respectively inserted into the slots of the axis frame 13 and the rear cover 6, so as to strengthen the connection strength between the pump shaft 4 and the front cover 1 and the rear cover 6.

[0017] In a further embodiment, Figure 7 As shown, the inner cavity of the front cover 1 is provided with a plurality of gradually expanding concave rings 14, which increase the flow space of the inner cavity of the front cover 1 and improve the head of the permanent magnet direct-drive pump; the shaft frame 13 is provided with three extended guide plates 131, which are connected to the inner wall of the liquid inlet 11 and are symmetrically distributed with the slot of the shaft frame 13 as the center, thereby ensuring the connection strength while increasing the flow space of the liquid inlet 11 and improving the head of the permanent magnet direct-drive pump.

[0018] In a further embodiment, Figure 2 , Figure 5 and Figure 7 As shown, it also includes a thrust bearing 9 and a rear thrust ring 93. The thrust bearing 9 includes a front thrust ring 91 and an interface ring 92. The front thrust ring 91 is coupled to the interface ring 92. The front thrust ring 91 is installed on a concave ring 14 in the inner cavity of the front cover 1 close to the liquid inlet 11. The interface ring 92 is installed at one end of the impeller 2 close to the front cover 1 to control the vertical and horizontal accuracy of the excitation winding and the magnetic capsule to form a complete electromagnetic field. The rear thrust ring 93 is sleeved on the pump shaft 4 and is located at the connection between the magnetic capsule 3 and the rear cover 6 to improve the stability of the permanent magnet direct drive pump.

[0019] Start the external power supply to energize the excitation winding 72 connected in the junction box 731 through the junction box 731. The excitation winding 72 generates an electromagnetic field. The electromagnetic field interacts with the permanent magnet rotor on the magnetic capsule 3, thereby driving the permanent magnet rotor in the magnetic capsule 3 to rotate. The permanent magnet rotor directly drives the impeller 2 to rotate along the central axis of the pump shaft 4. The impeller 2 discharges the air in the front cover 1 from the liquid outlet 12. The atmospheric pressure in the front cover 1 is lower than the external atmospheric pressure. A pressure difference is formed inside and outside the front cover 1. The liquid flows into the impeller 2 from the liquid inlet 11, and then the liquid is transported to the liquid outlet 12 through the impeller 2 and flows out from the liquid outlet 12.

Claims

1. A permanent magnet direct drive pump with a sealing structure, characterized in that: The pump comprises a front cover (1), an impeller (2), a magnetic capsule (3), a pump shaft (4), a bearing (5), a rear cover (6), a power supply part (7) and a plurality of sealing rings (8). The front cover (1) and the power supply part (7) are both provided with inner cavities and the inner cavities of the two are opposite to each other. The outer end of the front cover (1) is connected to the outer end of the power supply part (7) by bolts. One end of the impeller (2) is sleeved in the cavity of the front cover (1) and the other end is fixedly connected to one end of the magnetic capsule (3). The rear cover (6) is set in a cylindrical shape. The other end of the magnetic capsule (3) is sleeved inside the cylinder of the rear cover (6). The pump shaft (4) passes through the impeller (2) and the magnetic capsule (3) and the two ends of the pump shaft (4) are respectively inserted into the front cover (1) and the rear cover (6). The bearing (5) is sleeved outside the pump shaft (4) and is located between the inner hole of the magnetic capsule (3) and the pump shaft (4). The rear cover (6) is mounted on the outside of the cylinder in the power supply part (7). A plurality of sealing rings (8) are respectively sleeved on the connection between the rear cover (6) and the front cover (1) and the connection between the rear cover (6) and the power supply part (7). A plurality of permanent magnets are integrated on the magnetic capsule (3). When the magnetic capsule (3) rotates, the permanent magnets generate a fixed magnetic field. The power supply part (7) is provided with an excitation winding (72) and a junction box (731). The external power supply is electrically connected to the excitation winding (72) through the junction box (731). When the excitation winding (72) is energized, an electromagnetic field is generated. The electromagnetic field interacts with the permanent magnets on the magnetic capsule (3), thereby driving the magnetic capsule (3) to rotate and causing the impeller (2) to work. The inner and outer sides of the excitation winding (72) are both covered with a sealing insulation layer and filled with epoxy resin glue.

2. A permanent magnet direct drive pump with a sealing structure according to claim 1, characterized in that: The power supply part (7) comprises a power supply housing (71), an excitation winding (72) and a motor partition (73); the inner side of the power supply housing (71) is fixedly connected to the outer side of the motor partition (73); the terminal box (731) is fixedly installed at one end of the motor partition (73) away from the power supply housing (71); the excitation winding (72) is installed in the inner cavity of the power supply housing (71) and one end is in contact with the end surface of the motor partition (73); the excitation winding (72) is electrically connected to the terminal box (731); one end of the motor partition (73) close to the excitation winding (72) is in contact with the rear cover (6); and the excitation winding (72) is filled with epoxy resin glue.

3. A permanent magnet direct drive pump with a sealing structure according to claim 2, characterized in that: The end of the rear cover (6) connected to the front cover (1) is provided with a convex edge (61), and a sealing ring (8) is sleeved on the convex edge (61); the end of the excitation winding (72) close to the power supply housing (71) is sleeved with a sealing ring, and the end of the motor partition (73) connected to the excitation winding (72) is provided with two sealing steps (732), and the sealing ring (8) is sleeved on any one of the sealing steps (732).

4. The permanent magnet direct drive pump with a sealing structure according to claim 1, characterized in that: The front cover (1) is provided with a liquid inlet (11) and a liquid outlet (12) on the outside, the liquid inlet (11) being provided in the central area of ​​the front cover (1), the inner cavity of the front cover (1) being provided with a shaft frame (13), one end of the shaft frame (13) being fixedly connected to the liquid inlet (11), and the other end being provided with a slot matching the pump shaft (4), the bottom of the inner cylinder of the rear cover (6) being provided with a slot matching the pump shaft (4), and the two ends of the pump shaft (4) being respectively inserted into the slots of the shaft frame (13) and the rear cover (6).

5. The permanent magnet direct drive pump with a sealing structure according to claim 1, characterized in that: The inner cavity of the front cover (1) is provided with a plurality of concave rings (14) which expand step by step.

6. The permanent magnet direct drive pump with a sealing structure according to claim 4, characterized in that: Three guide plates (131) are extended from the shaft frame (13). The guide plates (131) are connected to the inner wall of the liquid inlet (11) and are symmetrically distributed with the slot of the shaft frame (13) as the center.

7. The permanent magnet direct drive pump with a sealing structure according to claim 5, characterized in that: It also includes a thrust bearing (9) and a rear thrust ring (93). The thrust bearing (9) includes a front thrust ring (91) and an interface ring (92). The front thrust ring (91) and the interface ring (92) are coupled and linked. The front thrust ring (91) is mounted on a concave ring (14) in the inner cavity of the front cover (1) close to the liquid inlet (11). The interface ring (92) is mounted on one end of the impeller (2) close to the front cover (1). The rear thrust ring (93) is sleeved on the pump shaft (4) and is located at the connection between the magnetic capsule (3) and the rear cover (6).

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