Electric tool

Patent metadata

Field	Value
Publication number	US-9768713-B2
Application number	US-201414893124-A
Country	US
Kind code	B2
Filing date	Aug 26, 2014
Priority date	Sep 28, 2013
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

An electric tool includes a brushless motor and an output part, which is driven by the brushless motor and to which a tip tool is mounted, and a tumbler switch. The tumbler switch applies, to the control unit, a stop signal for stopping the brushless motor at a neutral position, a forward rotation signal for forward rotating the brushless motor by an operation in a first direction, and a reverse rotation signal for reversely rotating the brushless motor by an operation in a second direction.

First claim

The invention claimed is:

1. An electric tool comprising:
a brushless motor, to which power is fed from a power supply;
an output part, which is driven by the brushless motor, and to which a tip tool is mounted;
a control unit configured to control a rotation direction and a rotating speed of the brushless motor; and
a tumbler switch connected to the control unit and configured to be operable at a neutral position, in a first direction or in a second direction,
wherein the tumbler switch is configured to:
output a stop instruction to the control unit to stop the brushless motor in a case where the switch is at a neutral position;
output a forward rotation instruction to the control unit to start up the brushless motor and forward rotate the brushless motor in a case where the switch is operated in a first direction; and
output a reverse rotation instruction to the control unit to start up the brushless motor and reversely rotate the brushless motor in a case where the switch is operated in a second direction,

wherein the switch is provided outside a current path between the power supply and the brushless motor.

2. The electric tool according to claim 1 , wherein when an instruction for rotating the brushless motor in an opposite direction to a previous rotation direction is applied to the control unit through an operation of the tumbler switch, the control unit is configured to start up the brushless motor in a soft start manner after the brushless motor is stopped.

3. The electric tool according to claim 1 , wherein when an instruction for rotating the brushless motor in an opposite direction to a previous rotation direction is applied to the control unit through an operation of the tumbler switch, the control unit is configured to start up the brushless motor in a slow soft start manner that is slower than a soft start manner if the brushless motor is being rotated.

4. The electric tool according to claim 1 , wherein the tumbler switch comprises a pair of switches and a pair of signal lines connected to the control unit,
wherein the pair of switches are operable at the neutral position, in the first direction or in the second direction through an operation of the tumbler switch, and
wherein the pair of signal lines is configured to apply a rotation direction signal indicating forward rotation/reverse rotation and a SW signal indicating switch ON/OFF states to the control unit.

Assignees

• Hitachi Koki Kk

Inventors

• Koizumi Toshiaki
• Tadokoro Naoki
• Iwata Kazutaka
• Nakayama Eiji

Classifications

• H01H23/30

  with stable centre positions and one or both end positions unstable · CPC title

• B25F5/00 Primary

  Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for · CPC title

• H02P3/06

  for stopping or slowing an individual dynamo-electric motor or dynamo-electric converter · CPC title

• B25B21/02

  with means for imparting impact to screwdriver blade or nut socket · CPC title

• H01H9/063

  enclosing a reversing switch · CPC title