IP Library › Granted Patent US 12,220,791
Granted Patent B2
US 12,220,791 · App. 18/409,099 · Granted Feb 11, 2025

Impact tool

Inventors: Ryunosuke Kumagai (Anjo, JP); Tokuo Hirabayashi (Anjo, JP); Hidenori Nagasaka (Anjo, JP); Manabu Sugimoto (Anjo, JP)
Assignee: MAKITA CORPORATION
B25B21/02B25B21/026B25F5/001B25F5/008B25F5/02B25B23/1405B25D11/04
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Quick Facts
Patent No.
US 12,220,791
App. No.
18/409,099
Granted
Feb 11, 2025
Kind
B2
Abstract

An impact tool includes a brushless motor having a rotor extending in a front-rear direction and disposed in a motor housing constituted by left, right and rear motor housings. A battery pack is disposed below the motor housing in an up-down direction. A plurality of first screws extend in a left-right direction and fix the left motor housing to the right motor housing. A plurality of second screws extend in the front-rear direction and fix the rear motor housing to the left and right motor housings. A fan is disposed between the rotor and the rear motor housing, a grip housing is disposed downward of the motor housing, and a planetary gear mechanism is disposed frontward of the motor. A spindle is disposed frontward of the planetary gear mechanism, a hammer is disposed on an outer circumference of the spindle, and an anvil is disposed frontward of the hammer.

Claims (35)

1. An impact tool, comprising:

a brushless motor including a stator and a rotor that is rotatable with respect to the stator, an axis of rotation of the rotor extending in a front-rear direction of the impact tool;

a motor housing that houses the brushless motor and includes a left motor housing, a right motor housing, and a rear motor housing;

a battery pack disposed below the motor housing in an up-down direction perpendicular to the front-rear direction;

a plurality of first screws that extend in a left-right direction perpendicular to the up-down direction and to the front-rear direction and fix the left motor housing to the right motor housing;

a plurality of second screws that extend in the front-rear direction and fix the rear motor housing to the left motor housing and to the right motor housing;

a fan disposed between the rotor and the rear motor housing;

a grip housing disposed downward of the motor housing in the up-down direction;

a planetary gear mechanism disposed frontward of the motor in the front-rear direction;

a spindle disposed frontward of the planetary gear mechanism in the front-rear direction;

a hammer disposed on an outer circumference of the spindle; and

an anvil disposed frontward of the hammer in the front-rear direction.

2. The impact tool according to claim 1 , further comprising:

a hammer case that houses a hammer;

wherein:

the planetary gear mechanism includes an internal gear and a plurality of planetary gears,

the internal gear includes a plurality of protruding parts, and

the hammer case includes a plurality of recessed parts into which the plurality of protruding parts extend.

3. The impact tool according to claim 2 , further comprising:

pins respectively supporting the planetary gears;

wherein:

the spindle holds the pins, and

the pins are immovable relative to the spindle in a direction toward the hammer.

4. The impact tool according to claim 2 , further comprising:

a bearing rotatable supporting the rotor; and

a bearing retainer holding the bearing;

wherein the bearing retainer includes a front protruding wall, and the front protruding wall is disposed on an outer side of the internal gear.

5. The impact tool according to claim 4 , wherein:

the stator includes an insulating member; and

the bearing retainer is disposed inside the insulating member.

6. The impact tool according to claim 4 , wherein:

the bearing retainer is coupled to the hammer case;

the stator includes an insulating member; and

the bearing retainer overlaps the insulating member in the front-rear direction.

7. The impact tool according to claim 4 , wherein the rotor includes a plurality of tubular permanent magnets having polarities that alternate in a circumferential direction.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 11, 2024
From: KUMAGAI, RYUNOSUKE; HIRABAYASHI, TOKUO; NAGASAKA, HIDENORI; SUGIMOTO, MANABU
To: MAKITA CORPORATION
Reel/Frame 066092/0193 →
Priority Claims (1)
JP 2012-285063 · Dec 27, 2012 · national
Continuity (5)
Division 17326724 · May 21, 2021
Continuation 16244356 · Jan 10, 2019
Division 15477388 · Apr 3, 2017
Continuation 14064278 · Oct 28, 2013
Related Publication 20240139915A1 · May 2, 2024
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