Chain saw

A chain saw, comprising:

• a housing extending substantially along a front and rear direction and formed with an accommodation space;
• an electric motor at least partially disposed in the accommodation space;
• a transmission system connected to the electric motor and capable of outputting a driving force;
• a control system comprising a circuit board assembly, the circuit board assembly extending in a plane;
• and
• a power supply assembly disposed on a rear side of the housing and used for powering the electric motor;
• wherein the circuit board assembly obliquely intersects with a first straight line extending along the front and rear direction;
• in a direction of a second straight line perpendicular to a direction of the first straight line and extending along an up and down direction, the electric motor has a first projection surface perpendicular to the direction of the second straight line and the circuit board assembly has a second projection surface perpendicular to the direction of the second straight line;
• the first projection surface of the electric motor at least partially overlaps the second projection surface of the circuit board assembly;
• the electric motor has a third projection surface in an upper and lower plane perpendicular to the direction of the first straight line and the circuit board assembly has a fourth projection surface in the upper and lower plane perpendicular to the direction of the first straight line;
• the third projection surface of the electric motor at least partially overlaps the fourth projection surface of the circuit board assembly;
• the electric motor comprises an electric motor shaft;
• the transmission system comprises an output shaft, a first gear connected to the output shaft, and a second gear connected to the electric motor shaft;
• a diameter of the second gear is smaller than a diameter of the first gear;
• the circuit board assembly comprises an upper end and an lower end;
• and
• the upper end is arranged on an upper side of the first gear and the lower end is arranged on an upper side of the second gear so that the circuit board assembly extends from the upper side of the first gear to the upper side of the second gear at an angle relative to the first straight line.