A power tool having a rotary hammer mechanism has a first motor; a driving mechanism configured to operate by power of the first motor in an action mode selected from a plurality of action modes including a first mode of at least rotationally driving a tool accessory and a second mode of only linearly driving the accessory; a tool holder configured to be rotationally driven by torque transmitted from the first motor; a second motor; a clutch member configured to transmit torque to the holder in a transmitting position and to interrupt the transmission in an interrupting position; and a transmitting mechanism configured to convert rotation of the second motor into linear motion and transmit the linear motion to the clutch member. When the tool body excessively rotates around the driving axis, the second motor moves the clutch member from the transmitting position via transmitting mechanism to interrupt the transmission.

A rotary hammer includes a housing, a first motor supported by the housing and defining a first motor axis, a second motor supported by the housing and defining a second motor axis that is coaxial with the first motor axis, and a spindle coupled to the first motor for receiving torque from the first motor, causing the spindle to rotate. The rotary hammer further includes a reciprocation mechanism operable to create a variable pressure air spring within the spindle. The reciprocation mechanism includes a piston configured to reciprocate within the spindle in response to receiving torque from the second motor, a striker that is selectively reciprocable within the spindle in response to reciprocation of the piston, and an anvil that is impacted by the striker when the striker reciprocates towards the tool bit. The anvil imparts axial impacts to the tool bit.

Power tool, in particular a hammer drill, including a housing, a tool fitting for receiving and holding a tool, an impact device for producing and transmitting impact pulses to the tool, and a rotation device for producing and transmitting a torque to the tool, wherein a working axis passing through the impact device is provided. The power tool includes a first drive unit having a first axis of rotation for driving the rotation device and a second drive unit having a second axis of rotation for driving the impact device, wherein the first and second drive units are arranged in such a way relative to one another in the housing that the first axis of rotation of the first drive unit is arranged at a first angle to the second axis of rotation of the second drive unit and at a second angle to the working axis.

A rotary hammer includes a motor and a spindle coupled to the motor for receiving torque from the motor. The spindle has an adjustable rotation speed. A reciprocation mechanism is operable to create a variable pressure air spring within the spindle and includes a piston configured to reciprocate within the spindle in response to receiving torque from the motor. The piston has an adjustable reciprocation frequency. A striker is selectively reciprocable within the spindle in response to reciprocation of the piston. A first transmission is transfers torque from the motor to the spindle and a second transmission is transfers torque from the motor to the reciprocation mechanism. The reciprocation frequency of the piston is adjustable independent of the rotation speed of the spindle. The rotation speed of the spindle is adjustable independent of the reciprocation frequency of the piston. At least one of the transmissions is a multi-speed transmission.

Power tool, in particular a hammer drill, including a housing, a tool fitting for receiving and holding a tool, an impact device for producing and transmitting impact pulses to the tool, and a rotation device for producing and transmitting a torque to the tool, wherein a working axis passing through the impact device is provided. The power tool includes a first drive unit having a first axis of rotation for driving the rotation device and a second drive unit having a second axis of rotation for driving the impact device, wherein the first and second drive units are arranged in such a way relative to one another in the housing that the first axis of rotation of the first drive unit is arranged at a first angle to the second axis of rotation of the second drive unit and at a second angle to the working axis.

A rotary hammer tool can include a housing, a first motor supported by the housing, a spindle rotated by the first motor, a second motor supported by the housing, and a reciprocation mechanism reciprocated by the second motor. The reciprocation mechanism can include a piston driven to reciprocate within the spindle and a striker to reciprocate within the spindle in response to reciprocation of the piston. The rotational speed of the spindle and a reciprocation frequency of the reciprocation mechanism may be independently controllable.

A hydraulic impact hammer having a hammer housing and a hydraulic piston. The hammer housing has means for attaching a hydraulic rotator converter which has a hydraulic rotator for rotating a drill bit for drilling holes on a surface while the drill bit receives pounding action from the piston. The drill bit has surface portions dimensioned to mate with bushing assembles and a cutout region to loosely engage with the locking mechanism in the hammer housing. After the holes are drilled, the converter is released from the hammer housing so as to allow a hammer tool with a larger diameter to be used for pounding over the holes. The hammer tool also has surface portions dimensioned to mate with the bushing assembles and a cutout region to engage with the locking mechanism so that the hammer tool can receive pounding action from the piston for pounding over the holes.