Abstract: Cordless power tools include a pistol housing having an upper portion that merges into a downwardly extending handle, a DC motor residing in the upper portion of the housing, the DC motor having a rotor that drives an output shaft; a torque transducer on board the tool in communication with the output shaft; and a dynamic motor control circuit residing in the housing in communication with the motor and torque transducer. The dynamic motor control circuit includes a Kelvin resistor in communication with the motor for measuring motor current and digital hall switches in communication with the motor for measuring motor speed. The motor current can vary by at least 100 A during operation.

Abstract: A cordless power tool battery pack including an onboard circuit configured to electronically communicate with an associated battery charging system. The onboard circuit communicates information relating to the batter pack to a microprocessor or the like within the battery charging system and charging of the battery pack is controlled based on such communication.

Abstract: A cordless power tool battery pack including an onboard circuit configured to electronically communicate with an associated battery charging system. The onboard circuit communicates information relating to the batter pack to a microprocessor or the like within the battery charging system and charging of the battery pack is controlled based on such communication.

Abstract: A cordless power tool battery pack including an onboard circuit configured to electronically communicate with an associated battery charging system. The onboard circuit communicates information relating to the batter pack to a microprocessor or the like within the battery charging system and charging of the battery pack is controlled based on such communication.

Abstract: An electric impact tool in which a rotating mass rotates in a forward direction to impact upon and transfer torque to an anvil, and rotates in a reverse direction opposite the forward direction in response to such impact. A direction sensor monitors the direction of rotation of the rotating mass, and a controller turns an electric motor on and off during respective forward and reverse rotation of the rotating mass. An energy storing mechanism may be used to absorb energy from reverse rotation of the rotating mass and release the absorbed energy to rotate the rotating mass in the forward direction. A controller may be used to store the angular position of the rotating mass upon each impact and turn off the motor prior to the following impact to avoid energizing the motor during stall.

Abstract: An electric impact tool in which a rotating mass rotates in a forward direction to impact upon and transfer torque to an anvil, and rotates in a reverse direction opposite the forward direction in response to such impact. A direction sensor monitors the direction of rotation of the rotating mass, and a controller turns an electric motor on and off during respective forward and reverse rotation of the rotating mass. An energy storing mechanism may be used to absorb energy from reverse rotation of the rotating mass and release the absorbed energy to rotate the rotating mass in the forward direction. A controller may be used to store the angular position of the rotating mass upon each impact and turn off the motor prior to the following impact to avoid energizing the motor during stall.

Abstract: A circuit board assembly comprising a main board, a connector board, and connector pins. The main board has a first face and a second face and terminating in an edge having a mounting area, the mounting area comprising at least one mounting pad on at least one of the first and the second faces. The connector board having a first face and a second face and comprising at least one through hole between the first and second faces. At least one connector pin is disposed in the at least one through hole and having a portion extending beyond each of the first and second faces of the connector board, wherein the edge of the main board and the second face of the connector board are abutted and the portion of the connector pin extending beyond the second face of the connector board is attached to the at least one mounting pad.