Power tool having first elastic member and second elastic member accommodated in first gear

A power tool comprising:

• a brushless motor including a rotor configured to rotate;
• a rectifier circuit configured to rectify an AC voltage;
• a smoothing capacitor configured to smooth the AC voltage rectified by the rectifier circuit to a pulsating voltage;
• an inverter circuit configured to perform switching operations to output the pulsating voltage to the brushless motor;
• a deceleration mechanism configured to decelerate a speed of a rotation of the rotor and configured to transmit the rotation to an end tool;
• and
• an elastic member disposed between a driving portion at a rotor side and a driven portion configured to transmit a rotating force to an end tool side, the elastic member being configured to transmit the rotating force of the driving portion to the driven portion;
• wherein an induced voltage is generated in the brushless motor upon rotations of the rotor,
• wherein the smoothing capacitor has a capacitance value so that:
• the AC voltage rectified by the rectifier circuit is smoothed to the pulsating voltage having a minimum value less than the induced voltage, a current flows through the brushless motor for a period during which the pulsating voltage is greater than the induced voltage, and no current flows through the brushless motor for a period during which the pulsating voltage is less than or equal to the induced voltage,
• wherein the elastic member includes:
• a first elastic member configured to transmit a load from the driving portion to the driven portion, the first elastic member being elastically deformed when transmitting the load from the driving portion to the driven portion;
• and
• a second elastic member configured to transmit a load from the driven portion to the driving portion, the second elastic member being elastically deformed when transmitting the load from the driven portion to the driving portion,
• wherein the deceleration mechanism includes:
• a pinion formed at an end portion of the rotor;
• the driving portion having a first gear in meshing engagement with the pinion;
• the driven portion having an intermediate shaft supporting the first gear;
• a second gear supported by the intermediate shaft and having a diameter smaller than that of the first gear;
• and
• a third gear in meshing engagement with the second gear, the first gear having a diameter greater than that of the third gear,
• wherein the first elastic member configured to transmit the rotation of the first gear to the intermediate shaft and the second elastic member configured to transmit a load from the intermediate shaft to the first gear are accommodated in the first gear while each of the first elastic member and the second elastic member is compressed by a prescribed amount.