Brushless motor

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.