Power Tool with High-Speed Electric Motor

A hand-held power tool comprising:

• a motor having a stator and a rotor and configured to rotate the rotor at a speed of at least 40,000 rpm;
• an output shaft directly driven by the rotor;
• a tool accessory shaft configured to support a tool accessory;
• and
• a two-stage speed reducing transmission operably connecting the output shaft to the tool accessory shaft,
• wherein the two-stage speed reducing transmission is configured to drive the tool accessory shaft at a rate less than or equal to 37.5% of the rotor speed.

A hand-held circular saw comprising:

• a base;
• a motor housing connected to the base;
• a gear housing connected to the motor housing;
• a blade case connected to the gear housing;
• a safety cover mounted for pivotable movement into the blade case;
• a tool accessory shaft configured to support a circular saw blade in the blade case;
• a motor in the motor housing having a stator and a rotor, the motor being configured to rotate the rotor at a speed of at least 40,000 rpm;
• an output shaft directly driven by the rotor;
• and
• a two-stage speed reducing transmission operably connecting the output shaft to the tool accessory shaft,
• wherein the two-stage speed reducing transmission is configured to drive the tool accessory shaft at a rate less than or equal to 15% of the rotor speed.