Patent ID: 6617719
Filing Date: 2003-09-09
Classification: H02K

Abstract:
A brushless motor comprising:a circuit protecting case; a holder disposed on said case; a motor shaft rotatably held by said holder; a stator disposed about said holder, said stator including a plurality of coils which surround said motor shaft; a yoke fixed to said motor shaft to rotate therewith, said yoke covering said stator with a given space therebetween; permanent magnets held by said yoke; a circuit substrate tightly held in said circuit protecting case; a drive circuit arranged on said circuit substrate, said drive circuit including a switching section which switches the path of current directed to said coils of the stator and a control section which controls a switching timing of said switching section, said switching section including a plurality of switching elements which generate a certain heat when operated; a partition wall provided in said circuit protection case to partition the interior of said case into a first chamber to which the switching elements of said switching section are exposed and a second chamber to which said control section is exposed; terminal pins extending from the coils of said stator; and connecting bus bars held by an inner case installed in said circuit protection case, each connecting bus bar having on end welded to a given part of said control section of said drive circuit and the other end welded to corresponding one of said terminal pins.