CN211501069U

CN211501069U - Miniature canned motor pump

Info

Publication number: CN211501069U
Application number: CN201921744087.8U
Authority: CN
Inventors: 刘一凡; 邹志; 欧耀辉; 李基伟
Original assignee: Hanyu Group JSCL
Current assignee: Hanyu Group JSCL
Priority date: 2019-10-17
Filing date: 2019-10-17
Publication date: 2020-09-15
Anticipated expiration: 2029-10-17

Abstract

A miniature canned motor pump comprises a motor, a rotor and an impeller, wherein the motor is provided with an iron core, the impeller is coaxially driven, and the impeller is formed by injection molding and is connected with the end surface of the rotor to form an impeller rotor assembly; the method is characterized in that: the end face of the rotor has an axial projection. This arch be in the impeller mould plastics connect in the terminal surface of rotor is in the face of, forms impeller and the mutual interlock of rotor terminal surface, compares the smooth plane of traditional design and meets the laminating mutually, increases the superficial area that impeller and rotor terminal surface combine and blocks with the directness of relative rotation displacement, can improve firm in connection degree and transmission moment of torsion, reaches durable, avoids breaking away from and leads to leaking.

Description

Miniature canned motor pump

Technical Field

The utility model relates to a miniature canned motor pump, IPC classification can belong to F04D13/06 or F04D 29/00.

Background

At present, a miniature shielding pump is generally used in a cooling liquid circulating system of an electric automobile, an impeller of the pump is in injection molding and connected to one end of a rotor in a traditional design, and the firmness and the sealing performance of the injection molding connection need to be further improved.

Common general knowledge on canned pumps can be found in pump theory and design, 2014 edition of the mechanical industry Press.

The traditional design similar to the present invention can be found in chinese patent documents CN104061169B, CN208749654U, etc.

Other terms and common knowledge can be found in the mechanical engineering handbook, the handbook of electric engineering, and the nomenclature of centrifugal pumps in accordance with the national standard GB/T7021-86, published by the mechanical industry Press, 1983 or 1997.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that a miniature canned motor pump is provided to improve traditional design impeller injection moulding and connect in firmness and the leakproofness of rotor one end.

The utility model provides a technical scheme is: a miniature canned motor pump comprises a motor, a rotor and an impeller, wherein the motor is provided with an iron core, the impeller is coaxially driven, and the impeller is formed by injection molding and is connected with the end surface of the rotor to form an impeller rotor assembly; the method is characterized in that: the end face of the rotor has an axial projection.

This arch when the impeller injection moulding connect in the terminal surface of rotor, form impeller and the mutual interlock of rotor terminal surface, compare the smooth plane of traditional design and meet the laminating mutually, increase the superficial area that impeller and rotor terminal surface combine and block with relative rotation displacement's directness, improved firm in connection degree and transmission moment of torsion under the same condition, can reach durable, avoid breaking away from and lead to leaking.

The projection is typically designed as a ring around the pump axis. This design increases the path length of the pumped media leakage primarily in the radial direction, thus significantly improving the seal and further contributing to the prevention of rotor rusting.

The annular protrusions are at least 2, and the height (i.e. axial length, the same applies below) of the annular larger protrusions is greater than the height of the annular smaller protrusions. Analysis and experiments show that the arrangement of the outer part with high inner part can further improve the firmness of connection and improve sealing.

The end face of the rotor is further designed with radially distributed axial projections connecting the annular projections. The connection further improves the firmness of the connection, in particular the structural rigidity and torsional strength, and thus the torque transmission capacity of the rotor to the impeller. The radial distribution of the axial convex is preferably at least 2, and the farther from the pump axis is higher than the closer to the pump axis, so that the torque transmitted from the rotor to the impeller can meet the requirement of product standard.

One of the more specific designs is that the protrusion is in a shape that the rotor is plastically encapsulated on the end face of the rotor by taking the iron core as an insert, or in a shape that the ferrite iron core without rust prevention is integrally molded on the end face of the rotor by powder metallurgy or bonding.

In a more specific design, when the impeller is injection molded and connected to one end of the rotor, a front cover plate and a rear cover plate are formed at two ends of the rotor to clamp the impeller. Also, the core of the rotor preferably has an axial through hole outside the central hole, and a plastic strip connecting the front cover plate and the rear cover plate is formed in the through hole when the impeller is injection molded and attached to one end of the rotor. Theoretical analysis and experiments show that the plastic strip is very favorable for preventing the cover plate from deforming and warping away from the end face of the rotor and improving the torque transmission capability of the rotor to the impeller. The inner wall of a central hole of the iron core of the rotor can be provided with an axially through groove, and a plastic strip formed in the groove is connected with the front end cover plate and the rear end cover plate during injection molding, so that the connection firmness and the torque transmission capacity can be further improved.

Another further development provides for: the impeller front disc is fixedly connected to the impeller. The closed impeller can achieve better pump performance and can adopt favorable process design.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Drawings

Figure 1 is a schematic view of a prior art micro canned pump impeller rotor assembly.

Fig. 2 is an exploded view of a 2 nd injection molded impeller rotor assembly of a micro canned motor pump according to an embodiment of the present invention.

Fig. 3 is a structure diagram of an impeller rotor assembly formed by injection molding for the 2 nd time of the micro shield pump according to the embodiment of the present invention.

Fig. 4 is a perspective view of the 1 st injection molded rotor of fig. 3 used as an insert for the 2 nd injection.

Fig. 5 is a cross-sectional view of a micro canned motor pump according to an embodiment of the present invention.

Reference numerals:

the impeller comprises an impeller 100, blades 11, an impeller rear disc 12, an impeller journal 13, a central hole 13-1, a bearing sleeve 13-2, a plastic strip 13-3, a front end cover plate 141, a rear end cover plate 142, a bulge 14-1, a bulge 14-2 and a plastic strip 14-3;

the magnetic component comprises a rotor 200, a ferromagnetic component 20, a ferromagnetic component peripheral surface 20-1, a ferromagnetic component end surface 20-2, a laminated core 21, a central hole 21-1, a groove 21-2, a hole 21-3, a magnetic steel groove 21-5, magnetic steel 22, a rotor end surface 23, a plastic-coated layer 23-1, an annular bulge 23-2, a radial bulge 23-3 and a ferromagnetic component peripheral surface plastic-coated layer 24;

a closed impeller rotor assembly 1200, an open impeller rotor assembly 1201 and an impeller front disc 3;

stator 4, bearing 5, pivot 6, pump body 7, pump cover 8, cavity 91, stator cavity 92.

Detailed Description

The embodiment of the utility model provides a miniature canned motor pump is similar CN104061169B, CN208749654U improve on the basis of traditional product and form. The impeller rotor assembly structure of the pump of conventional design is shown in fig. 1, and is mainly formed by injection molding of an impeller 100 'and attached to one end of a rotor 200'. The improvement points of the micro shield pump of the embodiment to the traditional design are as follows:

the shape of the rotor end and the axial through hole of the core;

-a structure for injection molding and attaching the impeller to one end of the rotor.

Not described in the specification, see CN104061169B, CN208749654U, modern pump theory and design, mechanical engineering handbook, motor engineering handbook and GB/T7021-86.

The miniature canned motor pump of the embodiment is an impeller coaxially driven by a permanent magnet motor. The structure of the closed impeller structure is shown in fig. 5, and the closed impeller structure comprises a closed impeller rotor assembly 1200, a stator 4, a bearing 5, a rotating shaft 6, a pump body 7 and a pump cover 8. The pump body 7 and the pump cover 8 enclose a cavity 91, and the cavity 91 is used for accommodating the closed impeller rotor assembly 1200 and the rotating shaft 6. One end of the rotating shaft 6 is pivoted on the pump body 7, and the other end is pivoted on the pump cover 8. The closed impeller rotor assembly 1200 is sleeved on the bearing 5 and the rotating shaft 6 in sequence. The pump body is also provided with a stator cavity 92 for receiving the stator 4. The closed impeller rotor assembly 1200 is driven by the electromagnetic force of the stator 4 to rotate at a high speed, thereby driving the liquid to flow. In addition, the closed impeller rotor assembly 1200 in fig. 5 removes the impeller front disk 3, i.e. becomes an open impeller rotor assembly 1201, and the rest of the structure and the working condition of the pump are basically unchanged, but the performance of the pump is changed.

The foregoing has generally described the inheritance of the prior art and the following has generally described the specific design of the improvements.

As shown in fig. 2-4, an open impeller rotor assembly 1201 includes an open impeller 100 and a rotor 200. Wherein:

a) the rotor 200 comprises a ferromagnetic assembly 20 and a plastic-coated layer 23 as the core ensemble of the rotor. The laminated core 21 is provided with a central hole 21-1 in the center and an axial groove 21-2 on the inner wall of the central hole. The grooves 21-2 are uniformly distributed around the pump axis, the number of the grooves is 2-4, and the grooves extend through the two ends of the laminated iron core 21. The laminated iron core 21 is also provided with through holes 21-3 which are uniformly distributed around the axis of the pump, the number of the through holes is 2 or more, and the preferable scheme is that the through holes are symmetrically and uniformly distributed with 4. The laminated iron core 21 is also provided with magnetic steel slots 21-5, and the magnetic steel 22 is installed in the magnetic steel slots 21-5 to assemble the ferromagnetic assembly 20.

Firstly, performing the injection molding for the 1 st time, putting the ferromagnetic component 20 as an insert (core mold) into a mold, and performing the following plastic packaging to obtain the rotor 200:

the plastic-coated layer 24 coats the outer cylindrical surface 20-1 of the ferromagnetic component 20;

the rotor end surface 23 of the end surface 20-2 of the cladding ferromagnetic component 20 is formed with 3 annular protrusions 23-2 with high outer parts and low inner parts and 8 radial protrusions 23-3, and the rest surfaces are covered with the plastic coating layer 23-1;

the central hole 21-1 and the through hole 21-3 are first prevented from being filled with plastic.

b) The impeller 100 is obtained by 2 nd injection molding, in which the rotor 200 is used as an insert (core mold) and is placed in a mold for molding. At this time:

the through hole 21-3, the central hole 21-1 and the groove 21-2 of the inner wall of the hole of the laminated core 21 of the rotor 200 are completely filled with the secondary injection molding material to form the impeller journal 13, the central hole 13-1 of the impeller rotor combination and the axial plastic strip 13-3 protruding in the radial direction, and extend towards the two ends of the rotor 200 to coat the end surface 20-2 of the ferromagnetic component 20 and the rotor end surface plastic coating layer 23-1 to form new end surface plastic coating layers, namely the front end cover plate 141 and the rear end cover plate 142;

the structure of the impeller 100 formed by injection molding comprises blades 11, an impeller rear disc 12 and bearing sleeves 13-2, wherein the two ends of a central hole 13-1 of an impeller journal 13 are enlarged. The blades 11 and the impeller journals 13 are respectively arranged on two sides of the impeller rear disk 12, the front and rear

end cover plates

141 and 142 are fixedly arranged on the impeller journals 13, the front end cover plate 141 is close to the impeller rear disk 12, and the rear end cover plate 142 is far away from the impeller rear disk 12.

Thus, the front and rear end covers 141 and 142 sandwich the rotor 200, thereby forming an open impeller rotor assembly 1201. The same material is preferably selected for the second injection molding, and the connection can be firmer.

And 2, injection molding:

the annular grooves formed between the annular protrusions 23-2 of the rotor 200 are filled with the injection molding material for the 2 nd time to form the protrusions 14-1 of the front end cover plate and the rear end cover plate, and the protrusions 14-1 and the protrusions 23-2 of the rotor 200 are mutually meshed, so that the radial movement of the two after cooling is avoided, the path of pumping media mainly leaking along the radial direction is obviously prolonged, the sealing effect is enhanced, and the laminated iron core 21 and the magnetic steel 22 are prevented from rusting;

the grooves formed between the radial protrusions 23-3 of the rotor 200 are filled with the second injection molding material to form the protrusions 14-2 of the front and rear end cover plates, and the protrusions 14-2 are engaged with the radial protrusions 23-3 of the rotor 200, so that the impeller 100 and the rotor 200 are prevented from rotating and displacing with each other, and the torsional strength between the impeller 100 and the rotor 200 is improved;

the 2 nd injection molding material also fills the axial groove 21-2 of the inner wall of the central hole 21-1 to form a plastic strip 13-3, the filling hole 21-3 forms a plastic strip 14-3, and the two plastic strips play a role of connecting pins for the front end cover plate 141 and the rear end cover plate 142, so that the capacity of transmitting torque from the rotor to the impeller can be improved. In particular, the plastic strip 14-3 has a greater ability to transmit torque to the impeller than it is away from the pump axis. Therefore, the outer diameter and/or the length of the rotor can be reduced, and the miniaturization of products is facilitated.

After the 2 nd injection molding is cooled, the workpiece is axially contracted, the plastic strips 13-3 and 14-3 tightly pull the front and rear

end cover plates

141 and 142 to clamp and compress the rotor 200 like a clamping plate, and the plastic coating layers formed by the 1 st injection molding and the 2 nd injection molding can be prevented from axially moving and separating. Wherein the plastic strip 14-3 is at a considerable distance from the central hole 21-1, the tightening is stronger.

The structure strengthens the torque transmission capacity and the sealing effect of the rotor to the impeller, and is very favorable for avoiding failure faults such as fracture and falling between the rotor and the impeller when the pump operates.

The above embodiment may be modified in design as follows:

1. the number, shape and size of the annular protrusions 23-2 and the radial protrusions 23-3 may be designed according to the pump power and may be adjusted to be optimal according to the results of the durability test. For example, when the power is low, the annular bulge 23-2 and the radial bulge 23-3 can be plastically molded only on the end face of the rotor, which is butted with the impeller, and the other end face can be flattened so as to simplify the mold.

2. The annular projection 23-2 may be changed from continuous to discontinuous, and together with the radial projections 23-3 may be changed to a plurality of individual projections distributed uniformly, which may provide more intermeshing surface area and direct blocking of the impeller and rotor faces, but may be less leak-proof than the former.

3. The holes 21-3 can be changed into blind holes which do not penetrate through the iron core according to the process requirement, and also have certain connection strengthening effect.

4. The ferromagnetic component 20 is formed by magnetizing the whole body after being processed by ferrite powder metallurgy or bonding and shaping. The ferrite rotor core is integrally firm and corrosion-resistant, plastic package and rust prevention are not needed, and annular and radial projections and the like of the required end face can be directly formed in powder metallurgy or bonding and shaping. The ferrite rotor core is also provided with an axial groove and a through hole on the inner wall of the central hole, so that a plastic strip which plays a role of a connecting pin for the front end cover plate and the rear end cover plate is formed when the impeller is connected with the rotor in an injection molding manner. The plastic-coated layers 24 and 23-1 on the cylindrical surface and the end surface of the rotor are omitted from fig. 3 to 5, which are generally applicable to the embodiment illustrating the design modification. While the ferromagnetic member 20 and its exploded structure are not applicable in fig. 2, the remaining embodiments are also applicable to the design modification in general.

5. The permanent magnet motor of the coaxial transmission impeller can also be changed into a squirrel cage motor, and the ring-shaped and radial-shaped protrusions of the required end surface can be formed to be the necessary end ring of the squirrel cage rotor when the squirrel cage rotor is subjected to aluminum casting, and then the rust-proof layer is formed by plastic package. The squirrel-cage rotor core is also provided with an axial groove and a through hole on the inner wall of the central hole, so that when the impeller is connected with the rotor by injection molding, a plastic strip which plays a role of a connecting pin for the front end cover plate and the rear end cover plate is formed.

6. The open impeller 100 in fig. 2 and 3, such as the impeller front disk 3 in fig. 5, is ultrasonically welded to the front end of the impeller 100, i.e., becomes a closed impeller. The impeller front disk 3 is an injection molding piece, and the injection molding material of the impeller 100 can be the same or different. The vanes 11 on the back disk of the impeller 100 can also be moved to the front disk 3 of the impeller-the vanes and the front disk 3 of the impeller are integrally injected, firstly the impeller 100 which is connected with the rotor by injection molding only has the back disk, and then the injection molding parts of the vanes 11 and the front disk 3 of the impeller are connected with the back disk of the impeller 100. The two processes have the advantages and can be adopted according to the circumstances.

Claims

1. A miniature canned motor pump comprises a rotor (200) with an iron core (20) of a motor and an impeller (100) coaxially driven by the rotor, wherein the impeller (100) is formed by injection molding and is connected with an end face (23) of the rotor (200) to form an impeller rotor assembly (1200, 1201); the method is characterized in that: the end face (23) of the rotor has an axial projection.

2. The micro canned pump of claim 1, wherein: the projection is annular about the pump axis.

3. The micro canned pump of claim 2, wherein: the number of the bulges is at least 2, and the height of the bulge with the larger ring shape is larger than that of the bulge with the smaller ring shape.

4. The micro canned pump of claim 2, wherein: the end face (23) of the rotor has radially distributed axial projections (23-3) which are connected with the annular projections (23-2).

5. The micro canned pump of claim 4, wherein: the radial distribution of the axial protrusions (23-3) is at least 2, wherein the farther from the pump axis is higher than the closer to the pump axis.

6. The micro canned pump of any one of claims 1 to 5, wherein: the bulges (23-2, 23-3) are in the shape that the rotor is plastically encapsulated on the end face (23) of the rotor by taking the iron core (20) of the rotor as an insert.

7. The micro canned pump of claim 6, wherein: the impeller rotor assembly (1200, 1201) has a front end cover plate (141) and a rear end cover plate (142) formed to cover the end face (23) and the protrusions (23-2, 23-3) of the rotor at the time of the injection molding.

8. The micro canned pump of claim 7, wherein: the iron core (20) of the rotor is provided with an axial through hole (21-3) outside the central hole (21-1), and the plastic strip (14-3) formed in the through hole (21-3) during injection molding is connected with the front end cover plate (141) and the rear end cover plate (142).

9. The micro canned pump of claim 8, wherein: the inner wall of a central hole (21-1) of the iron core (20) of the rotor is provided with a groove (21-2) which is axially penetrated, and a plastic strip (13-3) formed in the groove (21-2) during injection molding is connected with the front end cover plate (141) and the rear end cover plate (142).

10. The micro canned pump of any one of claims 1 to 5, wherein: the iron core (20) of the rotor is a ferrite powder metallurgy or bonding molding integral body, and the bulges (23-2, 23-3) are in the shape of the integral body on the end face (23) of the rotor.

11. The micro canned pump of claim 10, wherein: the impeller rotor assembly (1200, 1201) has a front end cover plate (141) and a rear end cover plate (142) formed to cover the end face (23) and the protrusions (23-2, 23-3) of the rotor at the time of the injection molding.

12. The micro canned pump of claim 11, wherein: the iron core (20) of the rotor is provided with an axial through hole (21-3) outside the central hole (21-1), and the plastic strip (14-3) formed in the through hole (21-3) during injection molding is connected with the front end cover plate (141) and the rear end cover plate (142).

13. The micro canned pump of claim 12, wherein: the inner wall of a central hole (21-1) of the iron core (20) of the rotor is provided with an axial groove (21-2), and a plastic strip (13-3) formed in the groove (21-2) during injection molding is connected with the front end cover plate (141) and the rear end cover plate (142).

14. The micro canned pump of any one of claims 1 to 5, wherein: the impeller front disk (3) is fixedly connected to the impeller (100).