Brushed motor

Patent metadata

Field	Value
Publication number	US-10637322-B2
Application number	US-201815987767-A
Country	US
Kind code	B2
Filing date	May 23, 2018
Priority date	Jun 13, 2017
Publication date	Apr 28, 2020
Grant date	Apr 28, 2020

Abstract

Provided is a brushed motor in which noise in a high rotational speed range is effectively decreased. A bar-shaped flat attachment 28 of synthetic resin is inserted along an axial line L into an opening of a slot 16 formed in a core 14 of a rotor 7 , and fixed with respect to the core 14 and/or windings 17 using adhesive agent. The flat attachment 28 has side surfaces 28 b and an inner peripheral surface 28 c . The side surfaces 28 b are engaged from an inner peripheral side with inclined surfaces 15 a of teeth 15 adjacent to each other across the opening of the slot 16 . The inner peripheral surface 28 c of the flat attachment 28 has two ridges 28 d protruding therefrom which are abutted against the windings 17 . The flat attachment 28 closes the opening of the slot 16 and shapes an outer peripheral surface 14 a of the core 14 into a flat cross sectional shape suitable for suppression of wind noise.

First claim

What is claimed is:

1. A brushed motor comprising:
a housing;
a field magnet disposed on an inner peripheral surface of the housing;
a rotor including a core, a rotary shaft rotatably supported in the housing, and a commutator disposed on the rotary shaft, the core having a plurality of teeth circumferentially arranged about an axial line of the rotary shaft, and a slot formed between the teeth, the slot having an opening on an outer peripheral side of the core and extending in an axial line direction of the core, and the rotor further including a winding wound on each of the teeth in the slot;
a brush slidably engaged with an outer peripheral surface of the commutator to supply power to the winding; and
a shape complementing member molded from an insulating material, the shape complementing member being inserted into the opening in the slot of the core from the axial line direction of the core, and fixed therein,
wherein the shape complementing member has an outer peripheral surface which is recessed with respect to an outer peripheral surface of the core in a radius direction of the core about the rotary shaft, the recess having a depth set in a range of from 0 to 1.5 mm.

2. The brushed motor according to claim 1 , wherein the slot and the shape complementing member each have a length in the axial line direction of the core along the rotary shaft, and
wherein a ratio of the length of the shape complementing member to the length of the slot is set in a range of from 50 to 100%.

3. The brushed motor according to any one of claim 1 , wherein, in the slot, the shape complementing member is engaged with the winding wound on the teeth so as to be biased in an outer peripheral direction, and is engaged with inner surfaces of the teeth extending on both sides of the opening of the slot.

4. The brushed motor according to any one of claim 1 , further comprising a cooling fan having an annular shape about the rotary shaft and disposed at an end in the axial line direction of the core,
wherein the cooling fan is connected with one end of the shape complementing member and integrally formed with the shape complementing member, the cooling fan being supported from the core via the shape complementing member.

5. The brushed motor according to claim 4 , wherein:
the cooling fan includes an annular base member and a plurality of fins circumferentially arranged on a side of the base member opposite a side of the base member facing the core; and
the one end of the shape complementing member is connected to the base member at a position circumferentially aligned with one of the fins of the cooling fan.

Assignees

• Mabuchi Motor Co

Inventors

• Hashimoto Yasuhiro
• Uzawa Hideyuki
• Yamagata Yasuhiro

Classifications

• H01R39/26

  Solid sliding contacts, e.g. carbon brush · CPC title

• H02K9/06

  with fans or impellers driven by the machine shaft · CPC title

• H02K5/148 Primary

  Slidably supported brushes · CPC title

• H02K3/487 Primary

  Slot-closing devices · CPC title

• H02K2213/03

  Machines characterised by numerical values, ranges, mathematical expressions or similar information · CPC title