Abstract: A method of operating a power tool having a motor and a controller is provided. The method includes: receiving a position of a variable-speed input mechanism mounted on the power tool; determining a target speed of the motor corresponding to the position of the variable-speed input mechanism; determining an underspeed threshold corresponding to the target speed; determining a rotational speed of the motor; and interrupting a supply of power to the motor if the rotational speed of the motor is less than the underspeed threshold.

Abstract: A method of operating a power tool having a motor and a controller is provided. The method includes: setting a protection time limit associated with a condition of the motor; taking protective action to shut down the motor if the condition of the motor persists for a duration of the protection time limit; and in response to occurrence of the condition during a start-up period of operation of the motor, extending the protection time limit for a duration of a constant-clutch time period to allow an output speed of the motor to reach or exceed a speed threshold, and taking protective action to shut down the motor if the output speed of the motor remains below the speed threshold for the duration of the constant-clutch time period.

Abstract: A cordless aw is provided with regenerative braking means that increases the number of repeated cuttings the saw is able to perform (x) per full discharge cycle of the battery pack, as compared to the number of repeated cuttings achievable by the same saw not employing a regenerative braking means (y) per full discharge cycle of the battery pack, such that x/y is approximately at least one of the following: i) 1.1 when cutting a Pressure-Treated (PT) lumber workpiece having a cross-sectional size of approximately 89 mm×89 mm±2 mm, ii) 1.15 when cutting a Spruce Pine Fir (SPF) lumber workpiece having a cross-sectional size of approximately 38 mm×89 mm±2 mm, or iii) 1.25 when cutting Medium Density Fiberboard (MDF) workpiece having a thickness of approximately 19 mm±1 mm and a width of approximately 76 mm±2 mm.

Abstract: A system is provided with a set of removable battery packs and a set of power tools each including a motor, a controller, and a battery receiving portion. For each power tool, the controller is configured to identify a type of battery pack coupled to the battery receiving portion and set a conduction band associated with phases of the motor or an advance angle by which phases of the motor are shifted based on the identified type of the battery pack.

Abstract: A system is provided with a set of removable battery packs and a set of power tools each including a motor, a controller, and a battery receiving portion. For each power tool, the controller is configured to identify a type of battery pack coupled to the battery receiving portion and limit a maximum amount of electric current drawn from the battery pack by the motor based on the identified type of the battery pack. The greater a ratio of an impedance of the motor to an impedance of the battery pack, the less the controller limits the maximum amount of electric current drawn from the battery pack such that for a given battery pack of the set of removable battery packs, the lower the impedance of the motor, the more current the motor draws from the given battery pack.

Abstract: A method of operating a power tool having a motor and a controller is provided. The method includes: receiving a position of a variable-speed input mechanism mounted on the power tool; determining a target speed of the motor corresponding to the position of the variable-speed input mechanism; determining an underspeed threshold corresponding to the target speed; determining a rotational speed of the motor; and interrupting a supply of power to the motor if the rotational speed of the motor is less than the underspeed threshold.

Abstract: A system is provided with a set of removable battery packs and a set of power tools each including a motor, a controller, and a battery receiving portion. For each power tool, the controller is configured to identify a type of battery pack coupled to the battery receiving portion and limit a maximum amount of electric current drawn from the battery pack by the motor based on the identified type of the battery pack. The greater a ratio of an impedance of the motor to an impedance of the battery pack, the less the controller limits the maximum amount of electric current drawn from the battery pack such that for a given battery pack of the set of removable battery packs, the lower the impedance of the motor, the more current the motor draws from the given battery pack.