A hammer drill having a motor mounted within a body and an output spindle; a tool holder mounted on the body capable of holding a cutting tool; a hammer mechanism having a piston; a reciprocating drive for converting rotary movement of the motor into reciprocating movement of the piston; a ram reciprocatingly driven by the piston via an air spring to strike a cutting tool held in the tool holder, the hammer mechanism performing one hammer cycle each time the ram strikes a cutting tool during normal use; an air replenishment mechanism capable of refreshing the air spring during certain time periods during normal use; the air replenishment mechanism capable of being adjusted to refresh the air spring during time periods within the hammer cycle and/or the system allows different volumes of air into or out of the air spring during the refreshment time periods.

A hammer drill having a motor mounted within a body and an output spindle; a tool holder mounted on the body capable of holding a cutting tool; a hammer mechanism having a piston; a reciprocating drive for converting rotary movement of the motor into reciprocating movement of the piston; a ram reciprocatingly driven by the piston via an air spring to strike a cutting tool held in the tool holder, the hammer mechanism performing one hammer cycle each time the ram strikes a cutting tool during normal use; an air replenishment mechanism capable of refreshing the air spring during certain time periods during normal use; the air replenishment mechanism capable of being adjusted to refresh the air spring during time periods within the hammer cycle and/or the system allows different volumes of air into or out of the air spring during the refreshment time periods.

A handheld power tool has a tool socket (2) to hold a tool (4) along a working axis (11), a motor (5) and a slip clutch (21) having a number of blocking elements. A sensor (27) serves to record a measured signal (28) as the measure of vibrations inside the handheld power tool (1). A band-pass filter (29) has a pass range in which a frequency lies that is equal to the product of the rotational speed of the wheel (22) on the drive side and the number N of blocking elements (24). The measured signal (28) filtered by the band-pass filter (29) is fed to an evaluation unit (30). When the filtered measured signal (28) exceeds a limit value, the evaluation unit (30) reduces the rotational speed of the motor (5).

A handheld power tool has a tool socket (2) to hold a tool (4) along a working axis (11), a motor (5) and a slip clutch (21) having a number of blocking elements. A sensor (27) serves to record a measured signal (28) as the measure of vibrations inside the handheld power tool (1). A band-pass filter (29) has a pass range in which a frequency lies that is equal to the product of the rotational speed of the wheel (22) on the drive side and the number N of blocking elements (24). The measured signal (28) filtered by the band-pass filter (29) is fed to an evaluation unit (30). When the filtered measured signal (28) exceeds a limit value, the evaluation unit (30) reduces the rotational speed of the motor (5).

A rotary hammer is adapted to impart axial impacts to a tool bit. The rotary hammer includes a motor, a spindle coupled to the motor for receiving torque from the motor, and a piston at least partially received within the spindle for reciprocation therein. A crank hub is coupled to the motor for receiving torque from the motor. The crank hub defines a rotational axis and includes a socket offset from the rotational axis. A pin includes a first portion at least partially received within the socket and a second portion fixed to the piston. The first portion of the pin is both pivotable within the socket and axially displaceable relative to the socket in response to rotation of the crank hub for reciprocating the piston between a forward-most position within the spindle and a rearward-most position within the spindle.

A rotary hammer is adapted to impart axial impacts to a tool bit. The rotary hammer includes a motor, a spindle coupled to the motor for receiving torque from the motor, and a piston at least partially received within the spindle for reciprocation therein. A crank hub is coupled to the motor for receiving torque from the motor. The crank hub defines a rotational axis and includes a socket offset from the rotational axis. A pin includes a first portion at least partially received within the socket and a second portion fixed to the piston. The first portion of the pin is both pivotable within the socket and axially displaceable relative to the socket in response to rotation of the crank hub for reciprocating the piston between a forward-most position within the spindle and a rearward-most position within the spindle.

An electric hand-held power tool, in particular a hammer drill and/or chipping hammer, having an electropneumatic impact mechanism which has a transmission housing, a guide tube arranged at least partially in the transmission housing, an exciter piston that is movable in an axial direction in the guide tube, a connecting rod coupled to the exciter piston, and an eccentric wheel which is coupled to the connecting rod on one side and is mounted so as to be rotatable with respect to the transmission housing via an end plate of the transmission housing on the other side, wherein the transmission housing is subdivided at least into a main shell and a cover shell separate from the main shell, such that the guide tube is braced against the main shell at least partially by the cover shell.

A power tool comprises a driving mechanism and a gear housing space (105a) which houses the driving mechanism. A lubricant is provided to the driving mechanism inside a gear housing (105). The driving mechanism includes a driving motor (110) having a motor shaft (111). The motor shaft (111) includes an inner communicating opening (191), an outer communicating opening (192) and an air passage (193) which connects the inner communicating opening (191) and the outer communicating opening (192). At least a part of the air passage (193) is arranged inside the motor shaft (111), and the passage (193) communicates with the gear housing space (105a) via the inner communicating opening (191) and also communicates with the outer space of the gear housing (105) via the outer communicating opening (192).

A power tool that includes a housing, an electric motor, an input device, a reciprocation drive assembly, a striker, an anvil, and an electronic controller is provided. The electronic controller can control the electric motor based on a state of the input device. The electronic controller can receive a first signal from the input device, the first signal indicating a first constant speed of the electric motor, and, in response to the first signal, set an operational speed of the electric motor to the first constant speed. The electronic controller can further receive a second signal from the input device, the second signal indicating a second constant speed of the electric motor that is greater than the first constant speed, and, in response to the second signal, set the operational speed of the electric motor to the second constant speed.

A power tool that includes a housing, an electric motor, an input device, a reciprocation drive assembly, a striker, an anvil, and an electronic controller is provided. The electronic controller can control the electric motor based on a state of the input device. The electronic controller can receive a first signal from the input device, the first signal indicating a first constant speed of the electric motor, and, in response to the first signal, set an operational speed of the electric motor to the first constant speed. The electronic controller can further receive a second signal from the input device, the second signal indicating a second constant speed of the electric motor that is greater than the first constant speed, and, in response to the second signal, set the operational speed of the electric motor to the second constant speed.