Power tool

Patent metadata

Field	Value
Publication number	US-10749405-B2
Application number	US-201815978467-A
Country	US
Kind code	B2
Filing date	May 14, 2018
Priority date	Jul 3, 2017
Publication date	Aug 18, 2020
Grant date	Aug 18, 2020

Abstract

Provided is a power tool whereby reduction is made for time-consuming effort and cost required in trouble, inspection and so forth related to a motor. A hammer drill, which is an example of a power tool, includes a plurality of coils, an insulator holding the plurality of coils, a terminal unit that is electrically connected to the plurality of coils and is attached to the insulator, a rotor that is rotatable with respect to the insulator, and a sensor board that detects rotation of the rotor and is attached to the terminal unit. The sensor board is detachable from the terminal unit, while the terminal unit is attached to the insulator.

First claim

What is claimed is:

1. A power tool comprising:
a plurality of coils;
an insulator holding the plurality of coils;
a terminal electrically connected to the plurality of coils, the terminal having a ring shape with an inner hole, and the terminal being attached to the insulator;
a rotor rotatable with respect to the insulator; and
a sensor board configured to detect a rotation of the rotor the sensor board being disposed inside the inner hole of the terminal, the sensor board being detachably attached to the terminal by a plurality of screws such that when the sensor board is detached from the terminal the terminal remains attached to the insulator.

2. The power tool according to claim 1 , further comprising a board presser member configured to press the sensor board against the terminal, the board presser member being made of resin.

3. The power tool according to claim 2 , wherein the terminal includes a guide portion directing the sensor board to an attachment position.

4. The power tool according to claim 1 , wherein the terminal includes a guide portion directing the sensor board to an attachment position.

5. A power tool comprising:
a plurality of coils;
an insulator holding the plurality of coils;
a terminal electrically connected to the plurality of coils, the terminal being attached to the insulator and including:
a terminal body made of resin, the terminal body having an inner hole, and
a plurality of conductive sheet metal members;

a rotor rotatable with respect to the insulator; and
a sensor board configured to detect a rotation of the rotor, the sensor board being attached to at least one of (i) the insulator, and (ii) the terminal, which is integrally attached to the insulator, the sensor board being located radially inside of the conductive sheet metal members.

6. The power tool according to claim 5 , further comprising a board presser member configured to attach the sensor board to the terminal, the board presser member being made of resin.

7. The power tool according to claim 6 , wherein:
the terminal has a ring shape with an inner hole, and
the sensor board is disposed inside the inner hole of the terminal.

8. The power tool according to claim 5 , wherein the terminal includes a guide portion directing the sensor board to an attachment position.

9. The power tool according to claim 8 , wherein:
the terminal has a ring shape with an inner hole, and
the sensor board is disposed inside the inner hole of the terminal.

10. The power tool according to claim 5 , wherein:
the terminal has a ring shape with an inner hole, and
the sensor board is disposed inside the inner hole of the terminal.

Assignees

• Makita Corp

Inventors

• Nagahama Tatsuya

Classifications

• B25D2250/095

  Electric motors · CPC title

• H02K3/50

  Fastening of winding heads, equalising connectors, or connections thereto · CPC title

• B25F5/008

  Cooling means · CPC title

• H02K29/06

  with position sensing devices (H02K29/03 takes precedence) · CPC title

• B25D17/00

  Details of, or accessories for, portable power-driven percussive tools {(details or components, e.g. casings, bodies, of portable power-driven tools not particularly related to the operation performed B25F5/00)} · CPC title