Abstract: A method of verifying a magnitude of a delivered output torque during a tightening operation of a threaded joint performed by a hand held power wrench including a housing, a motor, an output shaft, and a power transmission connecting the motor to the output shaft. The method includes: tightening the threaded joint; monitoring a magnitude of a direct torque acting along the power transmission during the tightening by at least one direct torque indicating sensor; monitoring a magnitude of a reaction torque transferred via the housing during the tightening by at least one reaction torque sensor; comparing the monitored magnitude of the direct torque with the monitored magnitude of the reaction torque; and determining, based on the comparison, whether the accuracy of the delivered output torque is acceptable.

Abstract: An electric pulse tool is configured to deliver torque in pulses on an output shaft thereof and includes an electric motor to drive the output shaft. The electric pulse tool is configured to, for each period, provide a current pulse to the electric motor during a current-on time interval, pause a current feed to the electric motor after the current-on time interval until an end of a torque pulse, determine a width of the torque pulse, and continue pausing the current feed to the electric motor during a pause interval from the end of the torque pulse. The pause interval is determined based on the width of the torque pulse such that a wider torque pulse results in a wider pause interval and a narrower torque pulse results in a shorter pause interval.

Abstract: A pneumatic impulse wrench includes a housing with a motor powered impulse unit, a pressure air inlet passage, an exhaust air outlet passage located in the housing and connected to the motor, and a motor power controlling valve mechanism located in the exhaust air outlet passage for automatic control of the exhaust air flow from the motor. A control pressure passage extends between the air inlet passage and the valve mechanism for communicating actual air inlet pressure to the valve mechanism. An operating mode shifting valve is provided in the housing and which is shiftable between an open position in which communication is allowed through the control pressure passage in an automatic valve mechanism operating mode, and a closed position in which communication through the control pressure passage is blocked in a manual valve mechanism operating mode.

Abstract: A method for estimating a clamp force obtained at tightening of a screw joint via a torque pulse sequence includes applying a primary torque pulse to rotate the screw joint in a tightening direction, measuring a torque level obtained by the primary torque pulse, applying a secondary torque pulse to move the screw joint in a loosening direction, measuring a torque level obtained by the secondary torque pulse, and calculating a difference between the torque level obtained by the primary torque pulse and the torque level obtained by the secondary torque pulse. The obtained clamp force is estimated from the difference between the obtained torque levels.

Abstract: In a method for an electric pulse tool, which is configured to deliver torque pulses on an output shaft, in each of a plurality of periods, a current pulse is provided to an electric motor during a current-on time and a current feed is paused during a current-off time. The method includes retrieving a parameter reflecting an amount of reaction force that the operator of the electric pulse tool can be exposed to, and determining the current-off time based on the parameter. The determined current off time includes a first off interval until an end of a torque pulse and a second off interval after the end of the torque pulse. The second off interval is based on a width of the torque pulse, such that a wider torque pulse results in a wider off interval and a narrower torque pulse results in a shorter off interval.

Abstract: A spindle of a drilling tool includes a socket portion having a first axial length (a1) of a first diameter (d1) for receiving and attaching a drill bit to the spindle. The spindle includes a fluid conduit having a second diameter (d2) narrower than (d1) for conveying a fluid to the socket portion. An interface space with diameter (d1) is formed between the fluid conduit and the drill bit when the drill bit is installed in the socket portion. A fluid conveyor, having a third diameter (d3) narrower than (d1), connects the fluid conduit to the drill bit to avoid fluid gathering in a periphery of the interface space. The fluid conveyor includes a first O-ring abutting a mouth of the fluid conduit, a second O-ring abutting a mouth of a fluid channel of the drill bit, and a spring between the first and second O-rings.

Abstract: A power tool, includes an electrical motor unit connectable to a battery unit, wherein: a step-up converter, connectable between the battery unit and electrical motor unit, converts a battery voltage Ubattery provided by the battery unit to a higher step-up voltage Ustep-up, and provides Ustep-up to the electrical motor unit as an output voltage Uoutput; a bypass circuit, arranged in parallel with the step-up converter, connects the battery unit to and provides Ubattery to the electrical motor unit as Uoutput; and at least one control unit is arranged to control the step-up converter and the bypass circuit, such that Uoutput can switch between Ubattery and Ustep-up, based on tool related parameters, including Uoutput, an output current Ioutput provided to the motor, a rotational speed ?motor of the motor unit multiplied with a torque T provided by the tool, and an output power Poutput provided to the electrical motor unit.

Abstract: An impulse wrench includes a housing, an electric motor with a rotor, a hydraulic pulse unit with an inertia drive member and an output shaft, and a coupling rigidly connecting the rotor to the inertia drive member to form an integrated rotating structure. The coupling includes a male coupling portion on the inertia drive member and a female coupling portion on the rotor, such that the male coupling portion is received in the female coupling portion to form the coupling. The male and female coupling portions have external and internal threaded sections, respectively, where an axial clamping force is accomplished at relative rotation of the rotor and the inertia drive member. The male coupling portion and the female coupling portion are provided with mating conical surfaces which are brought together by the axial clamping force to form a rigid connection between the rotor and the inertia drive member.

Abstract: A portable power tool includes a housing, a rotation motor supported in the housing and drivingly connected to an output shaft, and a connection device for attachment of a working implement to the output shaft. The connection device includes a conical coaxial socket portion formed integral with the output shaft and the working implement carrying collet to be received in the socket portion. The collet is radially elastic and intended to exert a radial clamping force on the working implement. A retaining sleeve partly surrounds the output shaft and is coupled to the output shaft via a thread connection. The retaining sleeve is provided with a radial inner flange for engaging and transferring an axial thrust force onto the collet to obtain a radial clamping force on the working implement introduced in the collet as the thread connection is tightened.

Abstract: A method performed by a monitoring node associated with a tool communication network of monitoring energy flow in a tightening tool connected to the communication network includes receiving, from the tightening tool, parameter values relating to current fed (I) into the tightening tool, angle (?) of a rotor in the tightening tool and torque (T) applied to a joint by the tightening tool. The method also includes calculating energy input to the tightening tool based on the received parameter values, calculating energy transferred to the joint by the tightening tool based on the received parameter values relating to the torque applied to the joint by the tightening tool and the angle (?) of the rotor in the tightening tool. The method further includes detecting that the calculated energy input deviates from the calculated energy transferred to the joint by more than a predetermined value.

Abstract: An electric pulse tool for performing tightening operations, where torque is delivered in pulses to tighten a screw joint, includes an output shaft, a sensor arranged to determine a parameter value associated with the tightening of the screw joint, a processor, and a memory containing instructions executable by the processor. The electrical pulse tool operates to provide torque pulses on the output shaft in a first direction until the determined parameter value associated with the tightening of the screw joint reaches within or above a predetermined first interval including a target parameter value. The electrical pulse tool also operates to provide at least one torque pulse on the output shaft in a second direction that is opposite to the first direction in case the determined parameter value exceeds the target parameter value within a predetermined second interval.

Abstract: A hand-held power tool includes an electrical motor unit which includes a stator and a rotor arranged concentrically outside the stator, wherein a heat pipe is arranged with a first end inside the stator, thermally connected to the stator, and a second end reaching outside of the stator and thermally connected to a cooling device having a heat sink for cooling the second end of the heat pipe. The heat pipe includes a phase changing fluid for transporting heat from the first end to the second end to be dissipated at the cooling device. A fan is arranged to provide a cooling air stream to the heat sink and the fan is arranged to provide a cooling air stream to the heat sink independently of an operation of the motor unit.

Abstract: A power tool including: a motor; a shaft for delivering a torque to a joint or the like, the shaft being drivingly connected to the motor; and a housing that at least partly houses the motor and the shaft. The shaft includes a longitudinal cavity in which a torque transducer is arranged to measure a torque acting over a portion of the shaft, wherein the longitudinal cavity includes: a first contact surface for torque transferring contact with a first end portion of the torque transducer; and a second contact surface, separated from the first contact surface, for torque transferring contact with a second end portion of the torque transducer, the portion over which the torque is measured being located between the first and second contact surfaces.

Abstract: A hydraulic torque impulse generator includes a drive cylinder with a hydraulic fluid chamber, an output shaft with an impulse receiving portion connected to a radially movable seal element and intermittently dividing the hydraulic fluid chamber into high and low pressure compartments, and cam profiles which can displace the seal element from an idling position to a high pressure pulse generating position. A by-pass passage communicates fluid between the high and low pressure compartments, and a valve element movable between closed and open positions controls the fluid flow. The valve element is closed during pressure build-up in the high pressure compartment and opens when a high pressure pulse is completed, and is part of a control spindle coupled to the drive cylinder. The control spindle rotates through an angular play by inherent kinetic energy at an abrupt stop of the drive cylinder at the generation of each high pressure pulse.

Abstract: A hydraulic screw tensioning device includes a tubular body, with a through opening and an annular cylinder chamber surrounding the through opening, and a tubular piston movably supported in the tubular body and connectable to a screw to be tensioned. The tubular piston includes a stepped outer portion and divides the annular cylinder chamber into a first pressure chamber and a second pressure chamber. The second pressure chamber is closed by an annular end cap secured to the tubular body. The first pressure chamber is connectable to a pressure source for hydraulic fluid. The second pressure chamber is connectable to a pressure source for a compressible medium via a conduit connector mounted on the annular end cap. The conduit connector extends radially in relation to a geometric axis (A-A) of the tubular body. A damage protecting structure is provided to protect the conduit connector against accidental physical damage.

Abstract: An electric torque delivering impulse tool includes a housing with a front end and a back end, an electric torque delivering motor with a rotor that is arranged to rotate with respect to a stator, an output shaft arranged at the front end of the housing, and a pulse unit intermittently coupling the motor to the output shaft, wherein the pulse unit includes an inertia drive member that is connected to the rotor. The rotor and the inertia drive member are rigidly assembled to each other without play so as to form one integrated rotatable structure which is mounted as one single unit inside the housing.

Abstract: An electric power tool includes an electrical motor adapted to drive a rotating shaft. The electric motor is adapted to be fed with a pulsed current where the pulsed current includes a main current pulse (A) in a first direction driving the rotating shaft in a first direction and adapted to provide a current (C) in an opposite direction following the main current pulse to retract the electrical power tool. The pulsed current prior to the current (C) in the opposite direction includes a first pre-pulse current pulse (B) in the same direction as the current in the opposite direction and of a magnitude lower than the current (C). The pulsed current prior to the main pulse includes a second pre-pulse current pulse (D) which is in the same direction as the main current pulse and of a magnitude lower than the main current pulse.

Abstract: An electric power tool, configured to perform tightening operations where torque is delivered in a series of pulses, includes an electrical motor adapted to drive a rotating shaft of the electric power tool, and an angle sensor for sensing a parameter related to an angular displacement of the electric power tool. The electric motor is adapted to be fed with a train of controlled current pulses. The electric power tool is adapted to control a current supplied in the current pulses based at least in part on an output signal from the angle sensor to not exceed a limit threshold value for the parameter related to an angular displacement of the electric power tool.

Abstract: A ratchet type power wrench includes a housing, a pressure medium powered actuator, a ratchet mechanism included in the housing and coupled to the actuator, an open ended output socket with a constant cross sectional dimension throughout a length thereof, which is rotatably supported in the housing and engaged by the ratchet mechanism, and an angle encoder provided to indicate angular displacements of the output socket. The angle encoder has a form of a separate unit included in a casing, the casing being attachable to either side of the housing for connecting the angle encoder to either end of the output socket. The angle encoder includes a rotatable signal initiating part and a movement sensor rigidly mounted in the casing, the rotatable signal initiating part being provided with at least one coupling dog adapted to engage cavities located at both ends of the output socket.