# US 2010/0166579 A1 · Brushless motor for fluid pump and fluid pump using the motor

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2010/0166579 A1
- Document ID: US20100166579A1
- Status: Published application
- Kind: A1
- Application number: 12/488,323
- Filed: 2009-06-19
- Published: 2010-07-01
- Earliest claimed: 2008-12-26
- Assignees: Donghee Industrial Co., Ltd.
- Inventors: Jongsang NOH; Jonggeun CHA; Jongman LEE
- Web page: https://patentgrep.com/patent/US20100166579A1

## CPC

- H02K 29/03: with a magnetic circuit specially adapted for avoiding torque ripples or self-starting problems
- F04D 5/002: {Regenerative pumps (for elastic fluids F04D23/008)}
- H02K 1/276: Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM]
- H02K 5/12: specially adapted for operating in liquid or gas (combined with cooling arrangements H02K9/00)
- 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)
- H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53})
- F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02)

## Abstract

The present invention provides a brushless motor for a fluid pump that allows implementing a fluid pump that overcomes problems of durability and reduction of energy efficiency due to DC motors in the related art and provides excellent operational characteristics, by ensuring a space allowing fluid to flow between a stator and a rotor, and ensuring and maintaining excellent driving characteristics of a motor, and a fluid pump using the brushless motor.

## Claims

### Claim 1

A brushless motor for a fluid pump, comprising:
a stator core having a cross section in which six core shoes symmetrically protrude toward the center of a circle and six slots for winding are formed between the core shoes,
wherein two core shoe grooves recessed in the longitudinal direction of the stator core the inner side of each of the core shoes are each formed with a center on a core shoe groove center line spaced apart at 8.4°±1° from a straight line passing through the center of the core shoe from the center of the stator core, and the width and depth of the core shoe grooves are 1.5 mm±0.5 mm and 0.53 mm±0.1 mm, respectively,
a rotor core, which is inserted in the stator core, has rectangular permanent magnet holes that are formed in the circumferential direction from the center of the rotor core to be filled with four permanent magnets,
symmetric bridge holes are formed at both ends of the permanent magnet hole,
the bridge hole has a first wall that is spaced apart at 14.7°±2° from a straight line passing through the center of two adjacent permanent magnet holes from the center of the rotor core, a second wall that is connected to the first wall and spaced inside while maintaining a uniform thickness of 0.6 mm±0.1 mm from the outer circumference of the rotor core, a third wall that is connected to the second wall and spaced apart at 0.3 mm±0.1 mm from and in parallel with a straight line passing through the center of two adjacent permanent magnet holes from the center of the rotor core, and a fourth wall that is connected with the first wall and spaced apart at 0.35 mm±0.1 mm from and in parallel with a wall, which is closer to the center of the rotor core, of the permanent magnet hole, and
the length of the fourth wall forming the bridge hole is set to 0.41 mm±0.1 mm.

### Claim 2 (depends on 1)

The brushless motor for a fluid pump according to claim 1, wherein the first wall to the fourth wall forming the bridge hole are connected in the order of the fourth wall—the first wall—the second wall—the third wall, and
the portion between the fourth wall and the third wall is communicated with the permanent magnet hole.

### Claim 3 (depends on 2)

A fluid pump using a brushless motor, comprising:
the brushless motor according to claim 2;
a cover in which the brushless motor is disposed;
a connector that is disposed to seal one side of the cover, has a terminal for supplying electricity to the brushless motor, and is equipped with a check valve discharging pumped fluid;
a spring buffer that elastically supports a rotary shaft of the brushless motor against the connector;
a lower casing that is disposed to seal the other side of the cover;
an upper casing that is disposed above the lower casing; and
an impeller that is disposed between the lower casing and the upper casing and pumps fluid by using rotational force transmitted from the rotary shaft of the brushless motor.