Water pump motor, and water pump using same

• US 9,318,931 B2
• Filed: 02/13/2012
• Issued: 04/19/2016
• Est. Priority Date: 08/17/2009
• Status: Active Grant

• Current Assignee: Amotech Co., Ltd.
• Original Assignee: Amotech Co., Ltd.
• Inventors: Kim, Byoung Soo
• Primary Examiner(s): Comley, Alexander
• Application Number:
  US13/371,913
• Publication Number:
  US 20120183421A1
• Time in Patent Office: 1,527 Days
• Field of Search: 417/423.11, 417/423.14, 417/424.2, 310/85, 310/86, 310/87, 310/104
• US Class Current: 1/1
• CPC Class Codes: D06F 2103/48 of the motor driving the pump
• CPC Class Codes: D06F 39/085 Arrangements or adaptations of pumps
• CPC Class Codes: F04D 13/06 the pump being electrically driven
• CPC Class Codes: F04D 13/0606 Canned motor pumps
• CPC Class Codes: F04D 13/0626 Details of the can
• CPC Class Codes: H02K 11/33 Drive circuits, e.g. power electronics H02K11/38 takes precedence
• CPC Class Codes: H02K 2211/03 Machines characterised by circuit boards, e.g. pcb
• CPC Class Codes: H02K 5/10 with arrangements for protection from ingress, e.g. water or fingers
• CPC Class Codes: H02K 5/128 using air-gap sleeves or air-gap discs
• CPC Class Codes: H02K 5/1672 radially supporting the rotary shaft at both ends of the rotor H02K5/1677 takes precedence
• CPC Class Codes: H02K 7/14 Structural association with mechanical loads, e.g. with hand-held machine tools or fans with fan or impeller for cooling the machine H02K9/06

Abstract

Provided is a water pump motor that implements a waterproof structure of a motor using a cover to seal a stator, and a water pump using the same. The water pump motor includes: a lower case on top of which a cylindrical protrusion is provided; a stator whose lower portion is supported on top of the protrusion and is sealed by the lower case; a stator case that is formed of an annular trench shape that seals the inner circumferential portion; a rotational shaft whose lower portion is rotatably supported by a groove; a rotor placed at the upper-inner circumferential portion of the stator case and at the center of which the rotational shaft is coupled to thus rotate according to an action with respect to the stator; and an upper case coupled with the lower case in an inverted cup shape.

Claims

1. A water pump motor comprising:

a lower case on top of which a cylindrical protrusion is provided;

a stator whose lower portion is supported on top of the cylindrical protrusion and is sealed by the lower case;

a stator case formed of an inner circumferential portion, an outer circumferential portion and an upper surface between upper end portions of the inner and outer circumferential portions, wherein a lower portion which extends from the inner circumferential portion of the stator case is sealed by a circular sealing plate, and a groove is formed at a center of the circular sealing plate, wherein the stator case is monolithically formed as a single piece having the inner circumferential portion, the outer circumferential portion, the upper surface and the circular sealing plate, which together form an annular trench accommodating the stator, and wherein a lower distal end portion of the outer circumferential portion is disposed below a bottom surface of the groove so as to abut against an upper surface of the lower case, and wherein the outer circumferential portion abuts and surrounds an outer circumferential surface of the cylindrical protrusion, thereby coupling the lower case and the stator case to each other;

a rotational shaft whose lower portion is rotatably supported by the groove;

a rotor that is placed at an upper-inner circumferential portion of the stator case and having its center coupled to the rotational shaft to thus rotate according to an action with respect to the stator; and

an upper case having an inverted cup shape and coupled directly with the lower case in such a way that an inner circumferential surface of the upper case is fitted circumferentially around an outer circumferential surface of the outer circumferential portion of the stator case, wherein an O-ring is disposed between the upper surface of the stator case and an inner surface of the upper case,

a middle case having a circular plate shape and disposed on top of the upper-inner circumferential portion of the stator case and inside the upper case to fluidically seal the rotor in a sealing state, wherein an upper portion of the rotational shaft is rotatably supported at a center of the middle case,

wherein an upper bearing is installed at the center of the middle case to thereby rotatably support the rotational shaft.

2. The water pump motor according to claim 1, wherein the upper case further comprises:

a flange that is bent at right angles at a lower portion of the upper case; and

a fastening unit that fastens the flange and the lower case.

3. The water pump motor according to claim 1, wherein the rotor comprises:

a back yoke that creates a magnetic circuit and at a center of which the rotational shaft is coupled; and

a main magnet that is formed of a ring shape so as to be coupled on an outer circumference of the back yoke and that is dividedly magnetized into a number of magnetic poles.

4. The water pump motor according to claim 3, wherein the rotor further comprises:

a number of sub-magnets corresponding to the number of the dividedly magnetized magnetic poles, and positioned adjacent to the back yoke and the main magnet.

5. The water pump motor according to claim 4, further comprising:

a rotor support that is formed on top and bottom surfaces of the back yoke and the main magnet for integration.

6. The water pump motor according to claim 1, further comprising:

a lower bearing that is installed at the groove of the circular sealing plate to thereby rotatably support the rotational shaft.

7. The water pump motor according to claim 1, further comprising:

a control printed circuit board (PCB) whose outer circumferential portion is supported between the stator and the cylindrical protrusion of the lower case, to thereby apply a drive signal for a coil of the stator.

8. The water pump motor according to claim 1, wherein the stator is characterized in that a coil is wound on a number of T-shaped teeth and then sealing resin is molded into an outer circumferential portion of the stator.

9. The water pump motor according to claim 1, wherein the rotor comprises:

a circular rod-shaped back yoke at a center of which the rotational shaft is coupled, on an outer circumferential surface of which a number of grooves are formed at regular intervals, and that creates a magnetic circuit;

a number of sub-magnets that are inserted and disposed in the grooves of the back yoke; and

a main magnet that is coupled on an outer circumferential portion of the back yoke in a ring shape and that is dividedly magnetized to have a number of magnetic poles corresponding to the number of the sub-magnets.

10. The water pump motor according to claim 1, wherein the rotor comprises:

a circular rod-shaped back yoke at a center of which the rotational shaft is coupled, and that creates a magnetic circuit;

a main magnet that is coupled on an outer circumferential portion of the back yoke in a ring shape, that is dividedly magnetized into a number of magnetic poles, and on an inner circumferential portion of which a groove is formed for each magnetic pole; and

a number of sub-magnets corresponding to the number of the dividedly magnetized magnetic poles and inserted into the grooves.

11. The water pump motor according to claim 9, wherein the sub-magnets are made into anisotropic magnet pieces and the main magnet is made into isotropic magnet pieces.