Power tool

Patent metadata

Field	Value
Publication number	US-9339923-B2
Application number	US-201013505034-A
Country	US
Kind code	B2
Filing date	Oct 20, 2010
Priority date	Nov 2, 2009
Publication date	May 17, 2016
Grant date	May 17, 2016

Abstract

Disclosed is a striking tool technology that contributes to reducing clutch sizes. The striking tool causes a tool bit to perform a striking operation in the long axis direction and to perform a rotational operation about the long axis, thereby causing the tool bit to carry out a predetermined machining operation. The striking tool comprises a tool body; a motor which is housed in the tool body and drives the tool bit; and a clutch which, on a route where the torque of the motor is transmitted to the tool bit, is disposed in a high rotational speed and low torque region that is a stage prior to where the rotational speed of the motor is reduced, which transmits the torque of the motor to the tool bit in a normal state, and which cuts off the transmission of torque generated about the tool bit long axis in the tool body if the torque exceeds a predetermined torque level.

First claim

I claim:

1. An impact tool, which causes a tool bit to perform striking movement in an axial direction of the tool bit and rotation around an axis of the tool bit, thereby causing the tool bit to perform a predetermined operation on a workpiece, comprising:
a tool body,
a motor that is housed in the tool body and drives the tool bit,
an impact drive mechanism configured to drive the tool bit by impact,
a rotary drive mechanism configured to rotationally drive the tool bit,
an impact drive shaft that is rotationally driven by the motor and drives the impact drive mechanism, and
a rotary drive shaft that is rotationally driven independently of the impact drive shaft by the motor and drives the rotary drive mechanism, and
a clutch that is disposed upstream of the rotary drive mechanism in a path of transmitting torque of the motor to the tool bit, and transmits torque of the motor to the rotary drive mechanism, while interrupting the torque transmission when the torque acting on the tool body around an axis of the tool bit exceeds a predetermined torque,
wherein the impact drive shaft and the rotary drive shaft are coaxially disposed, and the clutch is disposed on the rotary drive shaft.

2. The impact tool as defined in claim 1 , wherein the impact drive shaft and the rotary drive shaft are coaxially disposed such that the impact drive shaft is located radially inward and the rotary drive shaft is located radially outward.

Assignees

• Aoki Yonosuke
• Makita Corp

Inventors

• Aoki Yonosuke

Classifications

• B25D2250/145

  Electro-magnetic parts · CPC title

• B25D2216/0023

  Tools having a percussion-and-rotation mode · CPC title

• B25D16/003 Primary

  Clutches specially adapted therefor · CPC title

• B25D2216/0069

  Locking means · CPC title

• B25D2250/255

  Switches · CPC title