CN212838560U

CN212838560U - Rotor assembly of micro centrifugal pump and micro centrifugal pump applying same

Info

Publication number: CN212838560U
Application number: CN202021569900.5U
Authority: CN
Inventors: 廖勇; 吴炳华
Original assignee: Hanyu Group JSCL
Current assignee: Hanyu Group JSCL
Priority date: 2020-07-31
Filing date: 2020-07-31
Publication date: 2021-03-30
Anticipated expiration: 2030-07-31

Abstract

A rotor assembly of a micro centrifugal pump and the micro centrifugal pump using the same comprise a rotor plastic package part formed by primary injection molding by taking a rotating shaft and a magnetic core as inserts and a rotor shell formed by secondary injection molding by taking the rotor plastic package part as an insert; the rotor plastic package part comprises a rotating shaft, a magnetic core and a connecting block which is injected between the rotating shaft and the magnetic core and fixedly connects the rotating shaft and the magnetic core, the connecting block comprises a hollow cylinder and an end cover which radially extends from the end part of the cylinder, and the end cover partially covers the end surface of the magnetic core; the rotor shell and the rotor plastic package part are enclosed to form a magnetic core cavity wrapping the magnetic core, the rotor shell and the rotor plastic package part comprise an outer shell part covering a cylindrical surface of the magnetic core in an injection molding mode and a surrounding edge part extending inwards from the end part of the outer shell part in the radial direction, the end face of the magnetic core is exposed out of the surrounding edge part and covered by the part of the end cover, and the radial end face of the surrounding edge part is tightly attached to the radial end face. The problem of the magnetic powder on the rotor subassembly of this pump drops and the pivot takes place to incline in the manufacturing process is solved.

Description

Rotor assembly of micro centrifugal pump and micro centrifugal pump applying same

Technical Field

The utility model relates to a structure of miniature centrifugal pump especially relates to a structure of miniature centrifugal pump of improvement rotor subassembly structure, and its IPC classification is F04D.

Background

For electric home appliances such as ice makers and coffee makers, a micro-pump is usually used to transport the liquid inside. The structure of this kind of miniature water pump is including establishing pump body, the rotor subassembly in the rotor chamber, and wherein the rotor subassembly includes: the magnetic core and the impeller of fixing in the pivot, rotor subassembly rotationally assemble in the rotor cavity. Because the liquid in the electrical appliances such as ice making machine or coffee machine is for the people to eat, the magnetic core is with liquid direct contact in the work process of miniature water pump. At this time, the magnetic powder is easily dropped onto the liquid, and cannot satisfy the requirement of NSF 61.

In order to solve the problems, the magnetic core is integrally sealed and injected. The manufacturing method comprises the steps of putting the magnetic core and the rotating shaft into a mold for one-time injection molding to fix the rotating shaft on the magnetic core, then putting an assembly formed after one-time injection molding into the mold, positioning the rotating shaft, and injecting a plastic layer on the outer surface of the magnetic core of the assembly to wrap the assembly. Because the pressure in the mould cavity is large during secondary injection molding, the plastic impacts the magnetic core, so that the rotating shaft deforms after secondary injection molding, and the rotating vibration of the water pump is large.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model provides an improve miniature centrifugal pump of rotor subassembly structure.

The utility model adopts the technical proposal that:

a rotor assembly of a miniature centrifugal pump comprises a rotor plastic package part formed by primary injection molding by taking a rotating shaft and a magnetic core as inserts, and a rotor shell formed by secondary injection molding by taking the rotor plastic package part as the inserts; the rotor plastic package part comprises a rotating shaft, a magnetic core and a connecting block which is injected between the rotating shaft and the magnetic core and fixedly connects the rotating shaft and the magnetic core, the connecting block comprises a hollow cylinder and an end cover which radially extends from the end part of the cylinder, and the end cover partially covers the end surface of the magnetic core; the rotor shell and the rotor plastic package part are enclosed to form a magnetic core cavity wrapping the magnetic core, the rotor shell and the rotor plastic package part comprise an outer shell part covering a cylindrical surface of the magnetic core in an injection molding mode and a surrounding edge part extending inwards from the end part of the outer shell part in the radial direction, the end face of the magnetic core is exposed out of the surrounding edge part and covered by the part of the end cover, and the radial end face of the surrounding edge part is tightly attached to the radial end face.

The utility model discloses a rotor subassembly of centrifugal pump, mould plastics through the secondary and wrap up the magnetic core in the magnetic core intracavity, avoid the magnetic on the magnetic core to drop to on the liquid, and the rotor subassembly of this structure is when making the inserts with rotor plastic envelope portion and carrying out the secondary and mould plastics, the plastics of injection and the radial end face contact of the end cover of plastic envelope portion, do not take place the contact with the pivot, the impact of plastics to the pivot when reducing the secondary injection, the difficult bending deformation of pivot after making through the manufacturing of moulding plastics, reduce the vibrations of water pump during operation, promote the stability of water pump work.

Further, the axial projection of the end cap is circular. This design does benefit to when making the rotor shell, and the rotor plastic envelope portion avoids appearing the starving when making the rotor shell with the combination of end cover, leads to the magnetic core to expose outside the magnetic core chamber.

Furthermore, the end surface of the magnetic core is provided with an axial magnetic core lower concave part. This design does benefit to the joint strength of rotor plastic envelope portion and magnetic core, prevents to take place to skid between magnetic core and the rotor plastic envelope portion, leads to the water pump can not normally work.

Further, the end cover is provided with a downward axial concave part at the joint of the end cover and the rotating shaft. The arrangement of the lower concave part can provide a space on the end cover for the elastic deformation when the rotor shell is manufactured, so that the impact on the rotating shaft after the pressure of injected plastic is transmitted to the end cover when the rotor shell is manufactured is reduced.

Further, the axial cross section of the lower recess is stepped. The design can reduce the thickness of the end cover of the rotor plastic package part and prevent the end cover from deforming when the end cover is too thick during injection molding manufacturing.

Furthermore, the rotating shaft is provided with knurls which are positioned at the connecting part of the connecting block. The design is favorable for the connection strength between the rotor plastic package part and the rotating shaft, and the phenomenon that the water pump cannot normally work due to the fact that the rotating shaft and the rotor plastic package part slip is avoided.

A miniature centrifugal pump comprises a pump body provided with a rotor cavity, a pump cover, an impeller and any one of the rotor assemblies, wherein the rotor assembly is rotatably assembled in the rotating shaft cavity, and the impeller is fixed on the rotor assembly.

Further, the centrifugal pump further includes an upper bearing disposed between the rotor assembly and the impeller, and a spacer located adjacent one side of the rotor assembly that projects axially in a direction toward the rotor assembly by a projection. The design of this boss can reduce the axial of rotor subassembly and beat, reduces the vibrations of centrifugal pump during operation.

For a better understanding and an implementation, the present invention is described in detail below with reference to the accompanying drawings.

Drawings

FIG. 1 is a cross-sectional view of the centrifugal pump of the present invention;

fig. 2 is a schematic perspective view of the magnetic core of the present invention;

fig. 3 is a schematic perspective view of the rotor plastic package part of the present invention;

fig. 4 is a top view of the rotor plastic package part of the present invention;

fig. 5 is a cross-sectional view of the rotor plastic package part of the present invention;

fig. 6 is a schematic perspective view of the rotor assembly of the present invention;

fig. 7 is a cross-sectional view of the rotor assembly of the present invention;

wherein:

30-magnetic core cavity, 100-pump body, 110-pump body cavity, 200-pump cover, 300-rotor assembly, 310-rotor plastic package part, 311-rotating shaft, 311.1-knurling, 312-magnetic core, end surface of 312.1-magnetic core, 312.2-magnetic core lower concave part, 313-connecting block, 313.1-column body, 313.2-end cover, 313.3-lower concave part, 313.4-end cover radial end surface, 320-rotor shell, 321-outer shell part, 322-surrounding part, 322.1-radial end surface, 400-impeller, 500-upper bearing, 600-gasket, 700-lower bearing

Detailed Description

Referring to fig. 1 to 7, the present invention provides a rotor assembly of a micro centrifugal pump and a micro centrifugal pump using the same, wherein the centrifugal pump includes a pump body 100 having a rotor chamber, a pump cover 200, a rotor assembly 300 rotatably assembled in the rotor chamber 110, an impeller 400 fixed to the assembly, and an upper bearing 500 disposed between the rotor assembly 300 and the impeller 400.

The formation process of the rotor assembly 300 is as follows. Referring to fig. 5, the rotor plastic package portion 310 formed by one-time injection molding includes a rotating shaft 311, a magnetic core 312, and a plastic connecting block 313 formed therebetween and fixedly connecting the two. The connection block 313 comprises a hollow cylinder 313.1 and an end cap 313.2 extending radially from the end of the cylinder, the end cap 313.2 partially covering the end face 312.1 of the magnetic core. Then, referring to fig. 7, a rotor casing 320 is formed by performing secondary injection molding by using the rotor plastic-molded portion 310 as an insert, the rotor casing 320 and the rotor plastic-molded portion 310 enclose a core cavity 30 for wrapping the core 312, the rotor casing 320 includes an outer casing portion 321 which is injection-molded and covered on a cylindrical surface of the core and a peripheral portion 322 which extends radially inward from an end portion of the outer casing portion, the peripheral portion 322 covers a portion of the end surface of the core which is exposed out of the end cover, and a radial end surface 322.1 of the peripheral portion 322 is tightly attached to a radial end surface 313.4 of the end cover 313.2. The rotor subassembly that this technology formed, through moulding plastics with the magnetic core parcel in the magnetic core intracavity, avoid the magnetic on the magnetic core to drop to liquid on, and the rotor subassembly of this structure when the secondary is moulded plastics, the plastics of injection and the radial terminal surface contact of the end cover of plastic envelope portion do not take place the contact with the pivot, avoid the plastics of injection directly to the pivot impact lead to pivot bending deformation, play positive effect to the stability that promotes water pump work.

The axial projection of the end cap 313.2 is circular, see fig. 3 and 4. The design is favorable for the rotor shell injection molding, the rotor plastic package part is better and tightly connected with the end cover, and the phenomenon that the magnetic core is exposed out of the magnetic core cavity due to glue shortage during the rotor shell injection molding is avoided.

Referring to fig. 2 and 5, in order to enhance the connection strength between the rotor plastic-molded portion 310 and the magnetic core 312, the sliding between the magnetic core 312 and the rotor plastic-molded portion 310 is prevented, so that the water pump cannot normally operate. The end surface 312.1 of the core is provided with an axial core undercut 312.2.

Referring to fig. 5 or 7, in order to enhance the connection strength between the rotor plastic-sealed portion 310 and the rotating shaft 311, the rotating shaft 311 and the rotor plastic-sealed portion 310 are prevented from slipping, which may cause the water pump to fail to operate normally. Knurling 311.1 is arranged at the joint of the rotating shaft 311 and the connecting block 313.

The end cap 313.2, see fig. 3 to 5, is provided with a downwardly concave portion 313.3 which is axially downwardly concave at the connection with the rotation shaft 311. The arrangement of the concave part enables a structure for the end cover to generate elastic deformation to be formed on the end cover 313.2 when the rotor shell 320 is manufactured by injection molding, so that impact on the rotating shaft 311 after the pressure of injected plastics is transmitted to the end cover 313.2 in the process of manufacturing the rotor shell 320 by injection molding is reduced, and the probability of deformation of the rotating shaft is reduced.

Referring to fig. 1, the centrifugal pump of the present invention further includes a spacer 600 disposed between the rotor assembly 300 and the upper bearing 500. The spacer 600 axially projects a boss 610 in the direction of the rotor assembly at an end face adjacent to one side of the rotor assembly 300. The design of this boss can reduce the axial of rotor subassembly and beat, reduces the vibrations of centrifugal pump during operation. As a preferred embodiment of the present invention, the pump body cavity 110 of the centrifugal pump is further provided with a lower bearing 700 located at the bottom of the pump body cavity 110, and as another embodiment, the bottom of the pump body can form a shaft hole for the rotating shaft to pass through during injection molding.

See fig. 3 to 5, for the thickness of the end cover 313.2 that reduces rotor plastic envelope portion 310, prevent that the thickness of end cover 313.2 is too thick and take place to warp after moulding plastics, the utility model discloses in design into the ladder with the lower recess 313.3 of end cover 313.2 and sink, the axial section of the lower recess 313.3 of this rotor plastic envelope portion is the echelonment.

The present invention is not limited to the above embodiment, and if various modifications or variations of the present invention do not depart from the spirit and scope of the present invention, they are intended to be covered if they fall within the scope of the claims and the equivalent technology of the present invention.

Claims

1. The utility model provides a rotor subassembly of miniature centrifugal pump, includes rotor plastic envelope portion (310) that adopts pivot (311) and magnetic core (312) to once mould plastics for the inserts and form and with rotor plastic envelope portion (310) are rotor shell (320) that the inserts secondary formed of moulding plastics, its characterized in that:

the rotor plastic package part (310) comprises a rotating shaft (311), a magnetic core (312) and a connecting block (313) which is injected between the rotating shaft and the magnetic core and fixedly connects the rotating shaft and the magnetic core, the connecting block (313) comprises a hollow cylinder (313.1) and an end cover (313.2) which radially extends from the end of the cylinder, and the end cover (313.2) partially covers the end face (312.1) of the magnetic core;

the rotor shell (320) and the rotor plastic package part (310) form a magnetic core cavity (30) which wraps the magnetic core (312) in a surrounding mode, the magnetic core cavity comprises an outer shell part (321) which covers the cylindrical surface of the magnetic core in an injection molding mode and a surrounding part (322) which extends from the end part of the outer shell part radially inwards, the end face (312.1) of the magnetic core is exposed out of the end cover by the surrounding part (322) to cover, and the radial end face (322.1) of the surrounding part is tightly attached to the radial end face (313.4) of the end cover.

2. The rotor assembly of claim 1, wherein: the axial projection of the end cover (313.2) is circular.

3. The rotor assembly of claim 1, wherein: the end surface (312.1) of the magnetic core is provided with an axial magnetic core lower concave part (312.2).

4. A rotor assembly as claimed in claim 1 or 3, wherein: the end cover (313.2) is provided with an axial downward concave part (313.3) at the joint of the end cover and the rotating shaft (311).

5. The rotor assembly of claim 4, wherein: the axial cross-section of the undercut (313.3) is stepped.

6. The rotor assembly of claim 1, wherein: the rotating shaft (311) is provided with knurls (311.1) which are positioned at the connecting position of the connecting block (313).

7. The utility model provides a miniature centrifugal pump, is including establishing pump body (100) of rotor chamber, pump cover (200) and impeller (400), its characterized in that: comprising a rotor assembly (300) as claimed in any one of claims 1 to 6, the rotor assembly (300) being rotatably mounted in the shaft chamber (110), the impeller (400) being secured to the rotor assembly (300).

8. The micro centrifugal pump of claim 7, wherein: the impeller structure further comprises an upper bearing (500) and a gasket (600) which are arranged between the rotor assembly (300) and the impeller (400), wherein the gasket (600) is positioned close to one side of the rotor assembly (300) and axially protrudes towards the direction of the rotor assembly to form a boss (610).