A power tool comprises a housing, a motor assembly and an impact assembly configured to be driven by the motor assembly. The impact assembly comprises a hammer defining a hammer chamber therein and an anvil at least partially disposed in the hammer chamber and configured to rotationally drive an output shaft. The anvil comprises a body portion, an anvil chamber defined therein, and a reciprocating member configured to selectively move radially outwardly relative to the body portion to be selectively impacted by an impact member of the hammer so that the hammer selectively imparts rotational movement to the anvil. The anvil includes an active valve configured to control discharge of fluid from an anvil chamber to the hammer chamber. The active value variably opens based on variance of one or more physical characteristics of the fluid (e.g., at least one of volume, temperature, pressure, or viscosity of the fluid).

A switching device for an electric tool includes: an output shaft unit disposed in an outer casing, having an output shaft, a movable ratchet wheel mounted such that the movable ratchet wheel is movable axially along the output shaft and is non-rotatable therewith; a fixed ratchet unit having a fixed ratchet wheel sleeved around the output shaft and having ratchet teeth for meshing with ratchet teeth of the movable ratchet wheel; and a function switch unit having a switch ring mounted rotatably on the casing. Rotation of the switch ring about its axis results in rotation of pawls within the switch ring, thereby driving the pawls about its pivot points and meshing and/or non-meshing of the pawls with external ratchet teeth of the fixed ratchet wheel, thereby switching the output shaft among a continuous rotation, rotation in a single direction and simultaneously providing an axial impact during the rotation.

A rotary impact tool includes a motor housing, an electric motor supported in the motor housing, and a drive assembly for converting a continuous torque input from the motor to consecutive rotational impacts upon a workpiece. The drive assembly includes an anvil including an anvil lug and a hammer that is both rotationally and axially movable relative to the anvil. The hammer includes a hammer lug for imparting the consecutive rotational impacts upon the anvil lug. The rotary impact tool further comprises a printed circuit board assembly including a sensor that is configured to detect rotation of the anvil. The printed circuit board assembly is spaced from the anvil to define an axial gap therebetween.

A power tool including a housing, a brushless direct current (DC) motor, an impact mechanism including a hammer and an anvil, an output drive device, a position sensor, and a controller. The position sensor is adjacent to a relief feature, which may be a recessed relief feature or a raised relief feature, and is configured to generate an output signal indicative of a position of the anvil. The controller is configured to calculate a drive angle based on the determined position of the anvil, and control the brushless DC motor based on the drive angle of the anvil.

A power tool includes a housing, a brushless motor received in the housing, a power switch coupled to the housing and actuatable by a user, a controller configured to control power delivery to the motor in response to actuation of the power switch, and an output spindle configured to rotate when the motor is energized. The controller is configured to maintain an amount of current delivered to the motor to be less than or equal to a current limit by turning off or reducing power to the motor for a time period if the current exceeds the current limit and then restarting power delivery to the motor. The time period is greater than the duration of one full current cycle.

An impact power tool includes a motor, a controller, and an impact mechanism configured to rotationally drive an output spindle. The controller is configured to control power delivered to the motor, during a third phase of operation after a second phase of operation and starting upon expiration of a predetermined time period. The third phase has one or more of a third non-zero target rotational speed, a third duty cycle setting, a third conduction band setting, or a third advance angle setting. The controller is configured to control power delivered to the motor, during a fourth phase of operation after the third phase upon detection of a reduction in load on the output spindle or cessation of impacting. The fourth phase has one or more of a fourth non-zero target rotational speed, a fourth duty cycle setting, a fourth conduction band setting, or a fourth advance angle setting.

A rotary impact tool in one aspect of the present disclosure includes a motor, an impact mechanism, an impact detector, and a controller. The controller executes constant duty ratio control from when the motor is started until an impact is detected by the impact detector. The controller executes constant rotation speed control in response to detection of an impact by the impact detector.

An impact tool includes a housing having a motor housing portion and an impact housing portion, an electric motor supported in the motor housing, a battery pack supported by the housing for providing power to the motor; and a drive assembly supported by the impact housing portion. The drive assembly includes an anvil extending from the impact housing portion, a hammer that is both rotationally and axially movable relative to the anvil for imparting consecutive rotational impacts upon the anvil, and a spring for biasing the hammer in an axial direction toward the anvil. The impact tool further includes a boot covering the impact housing portion, a front retainer arranged on the boot, a plurality of lenses in the front retainer, a plurality of LEDs respectively arranged within one of the lenses, and a rear retainer arranged between the boot and the impact housing portion.

A rotary impact tool includes a housing, an electric motor, and a drive assembly for converting a continuous torque input from the motor to consecutive rotational impacts upon a workpiece. An anvil has a bore defining a hexagonal cross-sectional shape and having a nominal width of 7/16 inches. A hammer is rotationally and axially movable relative to the anvil for imparting the consecutive rotational impacts upon the anvil. A spring biases the hammer in an axial direction toward the anvil. A battery pack has a nominal voltage of at least 18 Volts and a nominal capacity of at least 5 Ah. The rotary impact tool has an overall weight including the battery pack that is less than or equal to 7.5 pounds. A second performance ratio of the rotary impact tool, defined as (η.sub.a x RPM.sub.no-load/Inertia.sub.hammer) x (1/216,000,000) is greater than 2.

Position sensing related to a component within a power tool. The component within the power tool is, for example, a hammer of an impact mechanism and can include one or more sensible features that allow a controller of the power tool to precisely determine the position, speed, and acceleration of the component. One or more sensors can be used to determine the rotational position of the hammer and the axial position of the hammer. The rotational position of the hammer can then be used to calculate, for example, rotational speed and acceleration of the hammer. With precise determinations of the rotational and axial position of the hammer, the controller of the power tool is able to precisely time the impact between the hammer and the anvil to optimize the impact between the hammer and the anvil (e.g., to maximize energy transfer between the hammer and the anvil).