Abstract: A method is provided for an electrically-driven tool to detect battery decline. The electrically-driven tool includes a battery, a controller and a kinetic device. The controller pre-stores a dataset of energy provision time including a data piece of energy provision time that signifies a predetermined time length presumed to be required by the battery to provide a predetermined amount of electric energy. The controller induces provision of the predetermined amount of electric energy to the kinetic device to have the kinetic device perform a predetermined stroke with a predetermined load, times a stroke time period taken by the predetermined stroke, and determines whether the stroke time period is greater than the predetermined time length. The controller outputs a battery abnormality signal when the stroke time period is greater than the predetermined time length.

Abstract: An electric power tool includes a power supply supplying electricity, a driving unit driving operation of the electric power tool, an operation unit to be operated by a user, main and redundant sensing units detecting the power supply, the driving unit and the operation unit, and a control unit including primary and secondary controllers that respectively make first and second determinations according to the detection made by the main and redundant sensing units. The control unit controls the driving unit to operate in a normal mode when both of the first and second determinations indicate that at least one of the power supply, the driving unit and the operation unit operates normally.

Abstract: An electric power tool includes a battery, a first switch connected to the battery, a driving unit, a sensing unit, a primary controller and a secondary controller. The driving unit includes a motor, a second switch connected to the motor and the first switch, and a switch-control circuit connected to the second switch. The sensing unit outputs a detection result to the primary and secondary controllers. The primary controller disables the driving unit when it is determined that there is a malfunction based on the detection result. The secondary controller controls the first switch to operate in a non-conducting state to cut off electricity supplied from the battery to the second switch when it is determined that there is a malfunction based on the detection result. When the first switch operates in a conducting state, the second switch provides the electricity to the motor under control of the switch-control circuit.

Abstract: A method of controlling a rotational speed of an electric tool is provided. The electric tool includes a battery, a battery voltage detection circuit, a motor unit, and a controller. The controller stores at least one regression equation of duty ratio on voltage, and detects a voltage of the battery through the battery voltage detection circuit. The controller obtains a duty ratio for a control signal by substituting the voltage of the battery into the at least one regression equation, and outputs the control signal with the duty ratio obtained from the at least one regression equation to the motor unit for controlling operation of the motor unit.

Abstract: A method of controlling firing mode for an electric nail gun is provided. The electric nail gun includes a control module that, when operating in a program selecting state in an intelligent firing mode, executes a single firing program or a continuous firing program based on which of a safety switch and a trigger switch of the electric nail gun is being activated . When executing the continuous firing program, the control module forbids execution of a nail firing action when determining that the electric nail gun has not been fired for longer than a predetermined time period.