A boring device according to one embodiment of the present invention includes: a cutting edge; a drive unit that rotationally drives the cutting edge; a feed flow path through which a cooling liquid is fed to the cutting edge; and a tube pump that forces the cooling liquid in the feed flow path to flow to the cutting edge. The tube pump includes a feed tube constituting a part of the feed flow path and a first pressing mechanism that presses the feed tube, and the first pressing mechanism is driven by the drive unit.

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 method for determining a recommendation of a gear to be engaged for a core drill. In the method, it is possible to use for example a drop in a rotational speed of a core bit of the core drill in the event of sudden deactivation of the motor of the core drill in order to determine the diameter of the core bit. Alternatively, the diameter of the core bit can be determined when the drill is started up or turned on. The diameter of the core bit is then used as the basis for the recommendation of the gear to be engaged. In a second aspect, the invention relates to a core drill with which the method can be carried out.

A portable electrical drilling assembly includes an electric motor rotating a gear contained within a gear box housing, a connector coupling the gear to a splined shaft with the splined shaft extending within and engaging an internal surface of a cutter or reamer with the shaft and cutter/reamer defining a cutter-spline drive, and a pivoting feed mechanism coupled to the gear box housing to move a spindle for receiving the cutter or reamer. The gear rotation rotates the splined shaft and reamer/cutter to drill/ream a hole, with the pivoting of the feed mechanism controlling the depth of the drilled or reamed hole. The separate coupling of the splined shaft and cutter/reamer and interchangeability of cutters/reamers allows the assembly to be used in a confined space while still achieving deep drilling of holes in workpieces. The cutter-spline drive can also be used in other drilling assemblies.

A multi-directional compliant shifting mechanism for a multi-speed power tool may couple a movable selector to a power transmission system of the tool, for selecting an operational speed of the multi-speed power tool. The complaint shifting mechanism may provide shifting compliance in a first direction in response to movement of the selector in a first direction, and may provide shifting compliance in a second direction in response to movement of the selector in a second direction. In one example, this multi-directional shifting compliance may be provided by interaction of the selector with a camming surface, in combination with a single compression spring. In another example, this multi-directional shifting compliance may be provided by first and second springs, selectively acting to provide compliance in the first and second directions.

A barring device attachment includes a right-angle worm drive gear box configured to accommodate mechanical input from an electric drill. The attachment is particularly suited to mount to an engine to arrest rotational motion thereof in order to provide maintenance thereon.

The present invention relates to the technical field of hand-held tools. Disclosed is a hand-held power tool, comprising: a housing; a motor; a chuck assembly; and a transmission mechanism having a drive shaft. The chuck assembly comprises a main body, a jaw, and an adjustment member threadedly connected to the jaw. The power tool has a drilling mode in which the main body, the jaw and the adjustment member rotate together, and an auto chuck mode in which the adjustment member and the main body can rotate relative to each other to realize opening and closing of the jaw. The power tool further comprises a first supporting member and a second supporting member used to rotatably support the main body at the housing. The first supporting member and the second supporting member are at least partially overlapped with the jaw in an axial direction of the drive shaft, such that the power tool is structurally compact in the axial direction. The main body is provided with an accommodation cavity therein. The first supporting member is positioned in the accommodation cavity, such that the tool is also structurally compact in a radial direction.

A power tool, in particular a hand-held power tool, preferably embodied as a cordless screwdriver, is equipped with a torque limiting unit in which the release torque is settable by way of a locking brace that is equipped with a spring brace for locking elements that abut axially against parts of a planetary drive, in particular the ring gear thereof or the planet carrier thereof as a last gear stage, the spring elements of the spring brace and the locking elements being located with a radial offset from one another.

A power tool is provided which includes a housing assembly; a motor assembly disposed in the housing assembly and having an output shaft; a trigger assembly coupled to the housing assembly and configured for use in actuating the motor assembly; a spindle; and a transmission assembly transmitting rotary power between the motor assembly and the spindle. The transmission assembly comprises a star compound gear train.

It is an object of the invention to provide a technique for enhancing the operability of a power tool. A representative screwdriver 100 is provided which has a motor 110 and a driving mechanism 120. The driving mechanism 120 has a rotation transmitting mechanism including a driving cam 137 and a driven cam 157, and a cam engagement state is switched by movement of the spindle 150 in a longitudinal direction of the spindle. The position of the spindle 150 in the longitudinal direction is detected by a detecting mechanism 162 that is disposed on the opposite side of the rotation transmitting mechanism from a front end region in the longitudinal direction of the spindle 150. A controller 180 controls the rotation speed of the motor 110 based on the detection result of the detecting mechanism 162 and drives the motor 110.