A thread forming tool comprises a thread generating region that extends along a helical line with a thread pitch angle and a thread direction of the thread to be formed and has an active profile corresponding to the thread profile of the thread to be formed, wherein the thread generating region has a thread tooth having a thread profile with a front thread tooth profile flank and a rear thread tooth profile flank, has a front flank relieved surface, adjoining the front thread tooth profile flank and has a rear flank relieved surface, adjoining the rear thread tooth profile flank, wherein the front flank relieved surface is isolated relative to a front thread tooth flank envelope, wherein the rear flank relieved surface is displaced relative to a rear transverse plane wherein the helical line is inclined to the rear relative to the rear transverse plane by the thread pitch angle.

A thread forming tool comprises a thread generating region that extends along a helical line with a thread pitch angle and a thread direction of the thread to be formed and has an active profile corresponding to the thread profile of the thread to be formed, wherein the thread generating region has a thread tooth having a thread profile with a front thread tooth profile flank and a rear thread tooth profile flank, has a front flank relieved surface, adjoining the front thread tooth profile flank and has a rear flank relieved surface, adjoining the rear thread tooth profile flank, wherein the front flank relieved surface is isolated relative to a front thread tooth flank envelope, wherein the rear flank relieved surface is displaced relative to a rear transverse plane wherein the helical line is inclined to the rear relative to the rear transverse plane by the thread pitch angle.

A tapping machine (10), for tapping perforated products such as nuts (14), bushings or the like, comprises a spindle (11) on the longitudinal axis (12) of which a tapping tool (13) is rotatably mounted which tapping tool (13) is provided with a stem (21) having a longitudinal axis and a head having a threading to be inserted inside an appropriate hole provided in a nut (14) to be threaded, as well as pusher devices (16) for pushing a nut (14) against the threading surface of the tapping tool (13). Said machine further comprises an anti-vibration centring group (19) which acts on the stem of the tapping tool (13), substantially constraining the tapping tool (13) in a radial direction, preventing a de-alignment of the longitudinal axis (12) of the stem of the tapping tool and maintaining freedom of rotation thereof. Said anti-vibration centring group (19) is selectively movable along the stem of the tapping tool (13) in a parallel direction to the longitudinal axis of said stem (21).

A power tool includes a housing, a motor disposed in the housing and configured to rotationally drive an output member, a power delivery switch coupled to the housing and actuatable to cause power to be delivered to the motor, and a tool holder rotationally driven by the output member to rotatably drive at least one of a drill bit, a socket, a fastening bit, a tool bit holder, and a tapping bit. A controller in the housing is configured to control power delivery to the motor in a user selected driving mode or tapping mode. In the driving mode, the controller causes the motor to be driven in a first direction when the power delivery switch is actuated. In the tapping mode, the controller causes the motor to be driven in alternating directions while the power delivery switch is continuously actuated, such that the motor is driven in the first direction for a first time period until a first tool operation parameter reaches a first threshold value and in an opposite second direction for a second time period until a second tool parameter reaches a second threshold value.

A tapping head configured to hold and drive different size taps with a slip joint that introduces a small amount of play bet ween the tap head and the tap to compensate for excessive lead that may damage the tap or the workpiece. The tapping head includes a base, a drive coupler, a drive sleeve, a driver, a clutch pack, a pressure ring, a clutch cover, a drive cover and a lock nut. The driver and drive sleeve are longitudinally coupled by splines that form a slip joint. The clutch pact includes discs that against the inside surface of the base and lower surface of the pressure ring. Mounted on the lower surface of the pressure ring are a plurality of clutch springs that force the pressure ring upward against the clutch pack. Disposed between the drive couple and the driver are thrust springs that exert downward forces on the driver. The clutch cover includes internal threads configured to attach to external threads formed on the base. By tightening the clutch cover on the base, the force exerted by the thrust springs on the pressure ring can be adjusted to change the amount of frictional forces exerted by the clutch pack.

A tapping head configured to hold and drive different size taps with a slip joint that introduces a small amount of play bet ween the tap head and the tap to compensate for excessive lead that may damage the tap or the workpiece. The tapping head includes a base, a drive coupler, a drive sleeve, a driver, a clutch pack, a pressure ring, a clutch cover, a drive cover and a lock nut. The driver and drive sleeve are longitudinally coupled by splines that form a slip joint. The clutch pact includes discs that against the inside surface of the base and lower surface of the pressure ring. Mounted on the lower surface of the pressure ring are a plurality of clutch springs that force the pressure ring upward against the clutch pack. Disposed between the drive couple and the driver are thrust springs that exert downward forces on the driver. The clutch cover includes internal threads configured to attach to external threads formed on the base. By tightening the clutch cover on the base, the force exerted by the thrust springs on the pressure ring can be adjusted to change the amount of frictional forces exerted by the clutch pack.

A device and method of tapping an engine component to orient a spark plug includes measuring a tap pitch, measuring a first distance between a tap end surface and a full tap tooth center at a first rotational location, calculating a phantom first tap tooth based on the pitch and first distance, determining a tap rotational offset from the first location to a location where the end surface intersects the phantom first tooth, calculating a tap rotational starting orientation that is the first location minus the tap rotational offset minus a spark plug offset, rotating a tool head to the rotational starting orientation, positioning the tap so the end surface is a pitch incremental distance away from the engine component, synchronizing a rotating speed of the tool head and a feed rate to the tap thread pitch, and operating the tool to cut or form threads in the engine component.

A device and method of tapping an engine component to orient a spark plug includes measuring a tap pitch, measuring a first distance between a tap end surface and a full tap tooth center at a first rotational location, calculating a phantom first tap tooth based on the pitch and first distance, determining a tap rotational offset from the first location to a location where the end surface intersects the phantom first tooth, calculating a tap rotational starting orientation that is the first location minus the tap rotational offset minus a spark plug offset, rotating a tool head to the rotational starting orientation, positioning the tap so the end surface is a pitch incremental distance away from the engine component, synchronizing a rotating speed of the tool head and a feed rate to the tap thread pitch, and operating the tool to cut or form threads in the engine component.

The invention involves the extraction process of a glow plug pencil (23) or a broken pencil (23) which is stuck in a cylinder head (13) housing (11) of a glow plug engine comprising a lower (19) and upper (17) part, so that the upper part (17) forms a shoulder (21) with the lower part (19), the pencil (23) being stuck in the lower part (19). The process is remarkable in that it includes a step (a) for drilling a bore in the pencil (23) according to the longitudinal direction of the latter which is performed with the use of a drill bit (1) comprising a drilling part (5) with flutes (7) and a shank (3) respectively having a diameter smaller and greater than the lower part diameter (19) of the housing (11) so that the shank (3) forms a shoulder (9) with the drilling part (5), and in that step a) for drilling the bore includes the drilling of the pencil (23) until the said shoulder (9) of the drill bit (1) is positioned to a stop against the shoulder (21) of the housing (11).

The invention involves the extraction process of a glow plug pencil (23) or a broken pencil (23) which is stuck in a cylinder head (13) housing (11) of a glow plug engine comprising a lower (19) and upper (17) part, so that the upper part (17) forms a shoulder (21) with the lower part (19), the pencil (23) being stuck in the lower part (19). The process is remarkable in that it includes a step (a) for drilling a bore in the pencil (23) according to the longitudinal direction of the latter which is performed with the use of a drill bit (1) comprising a drilling part (5) with flutes (7) and a shank (3) respectively having a diameter smaller and greater than the lower part diameter (19) of the housing (11) so that the shank (3) forms a shoulder (9) with the drilling part (5), and in that step a) for drilling the bore includes the drilling of the pencil (23) until the said shoulder (9) of the drill bit (1) is positioned to a stop against the shoulder (21) of the housing (11).