An example method includes performing a machining operation by providing linear movement of a tool along a feed axis relative to a workpiece while superimposing oscillation of the tool onto the feed axis and providing rotation of the tool relative to the workpiece. During an optimization mode, the machining operation is performed on a first workpiece portion while providing the linear movement at an initial feed velocity, and sequentially superimposing the oscillating at a plurality of different frequencies. An optimal oscillation frequency is determined from the plurality of different frequencies which causes the tool to apply less force to the first workpiece portion at the initial feed velocity than others of the frequencies. During a run mode, the machining operation is performed on a second workpiece portion having a same composition as the first workpiece portion while superimposing the oscillation at the optimal oscillation frequency.

A brushless motor includes a stator and a rotor installed in the stator. The stator includes a front insulating frame and a rear insulating frame. The rotor includes a rotating shaft, a front bearing, a rear bearing, a front-end cover and a rear-end cover. The front-end cover is located on the front side of the rotor and installed on the front bearing. The rear-end cover is located on the rear side of the rotor and is installed on the rear bearing and abuts against the rear insulating frame. The front side of the front insulating frame is provided with multiple first snap parts. The front-end cover is provided with multiple second snap parts in the circumference. The first snap parts are snap-fitted with the second snap parts.

A drilling device, including a motor, a battery, and a frame. The battery is electrically connected to the motor. The frame includes a base, a column supported by the base, and a drill support part configured to be movable relative to the base. The battery is disposed on the base such that the drill support part is configured to be movable relative to the battery.

A rail drill drive train can include a common drive end between a single drive motor and a common gear. A speed train end can extend from the common gear to rotate the drill spindle. A feed train end can independently extend from the common gear to advance and retract the drill spindle. The speed train end can include a sprag gear so that, without unmeshing any gears, the drill spindle is not unnecessarily rotated in the reverse direction when the drive motor is reversed to retract the drill spindle. A rail drill control circuit and related sensors can enable automatic operation throughout the complete drilling cycle without any manual input from the user other than starting the cycle. Such a fully automatic drilling cycle can minimize overall cycle time to preserve battery life and can free the user to perform other tasks between drill moving and clamping operations.

A chuck for supporting rotationally symmetrical workpieces to be machined, comprising a chuck body having at least three guideways worked into its end face running in the direction of the longitudinal axis of the chuck, at least three clamping jaws inserted individually into each of the guideways in a movable arrangement, and a driving means in a driving connection with the clamping jaws directly or via intermediate elements, with each of the clamping jaws of the chuck being adjustable during machining using driving means configured as an electric motor, with each clamping jaw having an electric motor arranged inside the chuck body, and when the chuck is stationary, the electric motors are electrically connected to a power source by means of a plug-and-socket connection and electrical cables, and/or when the chuck is rotating or at a standstill each electric motor is connected to the power source via an induction device.

An example method includes performing a machining operation by providing linear movement of a tool along a feed axis relative to a workpiece while superimposing oscillation of the tool onto the feed axis and providing rotation of the tool relative to the workpiece. During an optimization mode, the machining operation is performed on a first workpiece portion while providing the linear movement at an initial feed velocity, and sequentially superimposing the oscillating at a plurality of different frequencies. An optimal oscillation frequency is determined from the plurality of different frequencies which causes the tool to apply less force to the first workpiece portion at the initial feed velocity than others of the frequencies. During a run mode, the machining operation is performed on a second workpiece portion having a same composition as the first workpiece portion while superimposing the oscillation at the optimal oscillation frequency.

A device for clamping a workpiece has a receiving head in a housing connected to a rotary drive with a rigid drive connection between a drive motor and the receiving head, radially adjustable clamping jaws connected to a clamping drive externally clamping the workpiece, and linear drives displacing the clamping jaws and forming the clamping drive driven jointly by a gear transmission with a central gear coaxial to the drive shaft of the receiving head by a separate drive motor. The central gear can be driven synchronously with the receiving head in the clamping position of the clamping jaws, and the rotary drive for the central gear comprises a rigid drive connection between its drive motor and the central gear or a superimposed gear comprising two input shafts drive-connected to the drive motor for the rotary drive of the receiving head and to the drive motor for the central gear.

The present invention is a portable and rechargeable drill system that allows a user to conveniently carry on the user's body and perform work. As a preferred and non-limiting example, the portable and rechargeable drill system is lightweight and is comprised of a drill handpiece, a battery-powered control device, and a securing member or mechanism for the drill handpiece. The drill system may further comprise a control device case or holder. The drill handpiece preferably comprises a first end, a second end, a drill bit-spindle and housing assembly, a drill bit locking mechanism, a motor and housing assembly, and a power cord.

A power tool, such as a drilling power tool, configured to perform an easy hole start operation upon actuation of a trigger. When the trigger is actuated, the motor is driven at a low speed value. The motor speed is increased to a second speed value during a predetermined time threshold and then driven at the second speed value until the trigger is no longer actuated. In some embodiments, the easy hole start operation may be implemented by an easy hole start switch. In some embodiments, if the easy hole start operation persists for a time greater than a predetermined time threshold, then the motor will shut off.

A changer device for inserting a clamping head into and/or removing the clamping head from the clamping chuck, wherein the clamping head has a plurality of clamping jaws mutually displaceable in a radial direction and which can be mutually subjected to force by the changer device toward or away from one another in the radial direction.

The changer device has a base and a plurality of adjusting elements which are movably attached to the base and which in each case have at least one engagement portion for the application of force onto the clamping jaws.

The changer device has a drive member which is rotatably movable about a central axis relative to the base. The drive member is coupled by a gear mechanism to the adjusting elements such that by a rotational movement of the drive member the adjusting elements can be jointly moved toward one another or away from one another.