Electric tool

Abstract

In the brushless motor disposed in a hammer drill, while a stator core of a stator is formed by joining a plurality of divided cores divided in a circumferential direction, varnishes are applied over a coil and joining portions between the divided cores.

1 . An electric tool comprising
 a brushless motor including a stator, a rotor, and a plurality of coils, the stator including a stator core formed by laminating electromagnetic steel plates, the rotor including a rotation shaft, the plurality of coils being wound around the stator core via an insulating member, wherein   while the stator core is formed by joining a plurality of divided cores divided in a circumferential direction, a varnish or an adhesive is applied over the coils and joining portions between the divided cores.   
     
     
         2 . The electric tool according to  claim 1 , wherein
 the adhesive has a high thermal conductivity.   
     
     
         3 . (canceled) 
     
     
         4 . The electric tool according to  claim 1 , wherein
 the coils are wound around the respective divided cores.   
     
     
         5 - 6 . (canceled) 
     
     
         7 . The electric tool according to  claim 1 , wherein
 the stator includes a sensor circuit board including a rotation detecting element of the rotor, the sensor circuit board being fixed via a plurality of fixing pins directly fixed to the stator core.   
     
     
         8 . The electric tool according to  claim 7 , wherein
 the fixing pin are fixed across the two adjacent divided cores.   
     
     
         9 . The electric tool according to  claim 7 , wherein
 the fixing pins are press-fitted to a disk made of metal disposed on an end surface of the stator core.   
     
     
         10 . The electric tool according to  claim 1 , wherein
 each of the divided cores has a shape fixed with an integrally molded resin.   
     
     
         11 . The electric tool according to  claim 1 , wherein
 each of the divided cores has a shape fixed with a dust core coating an outer surface thereof.   
     
     
         12 . The electric tool according to  claim 1 , wherein
 the respective divided cores are fixed with a tubular fixing member made of metal manufactured by shrinkage fitting or cold fitting.   
     
     
         13 . The electric tool according to  claim 1 , wherein
 the respective divided cores have joining portions inclined with respect to an axial direction of the stator core.   
     
     
         14 . The electric tool according to  claim 1 , wherein
 the electromagnetic steel plates have a plate thickness of 0.25 mm or less.   
     
     
         15 - 38 . (canceled)