Power tool having noise reducing structure

Abstract

A power tool includes a container having a chamber to receive a motor which has a spindle attached to a pinion and extended out of the pinion. A reduction gearing includes a housing attached to the motor and having an internal gear, two plates rotatably received in the housing and each having three rotatable gears. The pinion is engaged with the gears of one of the plates which has another pinion engaged with the gears of another plate, to allow the plates and the gears to be rotated by the motor. The pinion of the motor is extended through one of the plates, to smoothly support the plates and the gears within the housing, and to reduce shocks, vibrations, or noises that may be generated by the plates and the gears.

1 . A power tool comprising: 
 a body including a container provided thereon, said container including a chamber formed therein,    a motor received in said chamber of said container, and including a spindle, a first pinion attached onto said spindle, and said spindle of said motor being extended outwardly beyond said first pinion,    a reduction gearing received in said chamber of said container, and including a housing attached to said motor and having an internal gear provided therein,    said reduction gearing including a first plate and a second plate rotatably received in said housing, three first gears rotatably attached to said first plate, and engaged with said first pinion, to allow said first gears and said first plate to be rotated by said motor, said first plate including a second pinion extended therefrom and having a bore formed therein to receive said spindle of said motor, and to smoothly support said first plate in said housing,    said reduction gearing further including three second gears rotatably attached to said second plate, and engaged with said second pinion of said first plate, to allow said second gears and said second plate to be rotated by said motor via said first plate and said first gears, and    a driving device attached to said second plate, and thus rotated by said motor via said first plate and said second plate.    
   
   
       2 . The power tool as claimed in  claim 1 , wherein said first plate includes three holes formed therein, and three pins attached to said holes of said first plate, and engaged in said first gears respectively, to attach said first gears to said first plate.  
   
   
       3 . The power tool as claimed in  claim 1 , wherein said second plate includes three holes formed therein, and three pins attached to said holes of said second plate, and engaged in said second gears respectively, to attach said second gears to said second plate.  
   
   
       4 . The power tool as claimed in  claim 1 , wherein said second plate includes a non-circular orifice formed therein, and said driving device includes a driving shank having a non-circular end engaged into said non-circular orifice of said second plate, to allow said driving device to be rotated in concert with said second plate.  
   
   
       5 . The power tool as claimed in  claim 4 , wherein said driving device includes at least one fastener engaged with said driving shank, to secure said driving shank to said second plate.  
   
   
       6 . The power tool as claimed in  claim 1 , wherein said reduction gearing includes a panel received in said housing, and engaged with said first gears, to stably retain said first gears between said panel and said first plate.  
   
   
       7 . The power tool as claimed in  claim 1 , wherein said reduction gearing includes a panel received in said housing, and engaged with said second gears, to stably retain said second gears between said panel and said second plate.  
   
   
       8 . The power tool as claimed in  claim 1 , wherein said housing includes a cover secured thereto, and attached to said motor.