Abstract: A torque transducer unit for in-line calibration measurement of the output torque of a power wrench (S) includes a torque transferring spindle provided with a torque sensing device, two constant velocity universal joints, for instance Rzeppa-type couplings, and two coupling members for connecting the spindle at one end to the output shaft of a power wrench (S) and at the opposite end to a test joint. The spindle and the torque sensing device are protected from bending and friction related forces by the universal joints such that occurring misalignments between the power wrench (S) and the test joint do not jeopardize an accurate and reliable torque measurement.

Abstract: A device for test running of power nut runners comprises a main body (10;50) with a nut (11;54), a screw (12;52) with a nut runner engaging head (13;55), a clamping element (14;56) co-operating with the screw (12;52), and spring unit (17;59) to be clamped between the clamping element (14;56) and the main body (10;50) to generate a torque resistance on the screw (12;52), wherein a one-way clutch (24;64) is provided between the nut (11;54) and the main body (10;50) to prevent rotation of the nut (11;54) at rotation of the screw (12;52) in the tightening direction and to permit rotation of the nut (11) when rotating the screw (12;52) in the loosening direction, a friction clutch (30;72,73) between the nut (11;54) and the main body (10;50) is arranged to prevent rotation of the nut (11;54) during loosening of the screw (12;52), and a lock element (34;70) secured to the screw (12;52) is arranged to rotationally lock the screw (12:52) to the nut (11;54) at continued rotation of the screw (12;52) in the loosening di

Abstract: A pneumatic power wrench comprises a housing (10) with a pressure air supply passage (16), a motor (13) and an adjustable pressure responsive shut-off valve (17) located in the air supply passage (16) and including a valve element (21) and a bias spring (25) supported in one direction by the valve element (21) and in the opposite direction by a movable spring support (26), and a manually operated torque setting mechanism (31,32) for setting the spring support (26) in various positions, thereby varying the pre-tension of the spring (25) a swell as output torque level of the motor (13), wherein the setting mechanism (31,32) comprises an adjustment unit (32) which is rotatively journalled in the housing (10) and carrying two or more adjustable stop elements (31) arranged to be selectively brought into engagement with the spring support (26) and individually set at different positions corresponding to desired different output torque levels of the wrench.

Abstract: A portable power tool with a rotation motor (11) drivingly connected to a working implement carrying chuck (16) via a drive shaft (13), wherein a rotation locking mechanism (19) is arranged to lock the drive shaft (13) for enabling tightening or loosening the chuck (16) at attachment or removal of a working implement, wherein axial key surfaces (31) on the drive shaft (13) are arranged to be selectively engaged by mating key surfaces (32) on an axially movable but substantially non-rotative coupling unit (33,34) as the latter is shifted from an inactive rest position to an active position.

Abstract: A torque responsive release clutch intended for a power nutrunner and comprises a driving clutch half (11) and a driven clutch half (10) coupled to each other for torque transfer by means of axially directed teeth (16, 17), wherein one of the clutch halves is axially movable between an engagement position and a release position against the action of a bias spring (13). Each one of the teeth (16) of one of the clutch halves (10) has a substantially prismatic shape and extends axially from a base portion (19) to a top portion (20) and comprises two surfaces (22, 23) which form between them a ridge (25). The base portion (19) of the tooth (16) has a radial extent from an inner diameter (d1 to an outer diameter (d2), and the ridge (25) extends from the inner diameter (d1 at the base portion (19) to the outer diameter (d2) at the top portion (20).

Abstract: A portable power tool with a rotation motor (11) drivingly connected to a working implement carrying chuck (16) via a drive shaft (13), wherein a rotation locking mechanism (19) is arranged to lock the drive shaft (13) in alternative directions via two freewheel couplings (21, 22), one “forward” rotation locking coupling (21) and one “reverse” rotation locking coupling (22). Both couplings (21, 22) are supported in an axially displaceable coupling sleeve (23) which is connected to an external maneuver ring element (24) on the outside of the housing (10) for shifting of the “forward” and “reverse” locking couplings (21, 22) between active and inactive positions, thereby accomplishing locking of the drive shaft (13) in either the “forward” direction or the “reverse” direction for loosening or tightening the chuck (16).

Abstract: A pneumatic vane motor with a stator cylinder having an air inlet opening and an air outlet opening, a rotor eccentrically journalled in the cylinder and carrying a number of sliding vanes which divide the cylinder into moving cells, wherein the cylinder comprises a by-pass passage located between the air inlet opening and the air outlet opening and arranged to leak air from a pressurized working cell into a preceding cell before the working cell reaches the outlet opening, thereby using a preceding cell as an expansion volume for sound attenuation.

Abstract: A method and a power tool system are provided for performing screw joint tightening using a pneumatic torque impulse power tool that is controlled by a control unit. A torque magnitude and a torque growth are calculated based on signals delivered by an angle sensor, and pressurized air is supplied to the power tool via a flow regulating valve which is successively adjustable between zero and full power flow. The flow regulating valve is controlled by the control unit to deliver a reduced power air flow to the power tool before and during a first delivered impulse, and then to deliver full power flow until a certain torque magnitude or a percentage of a target torque level is reached, whereafter the air supply flow is again reduced until the target torque level is reached, and when the target torque level is reached the air flow is shut off.

Abstract: In an impulse wrench there is provided an impulse unit with a motor driven inertia drive member, and a movement detecting device arranged to detect an angular movement of the inertia drive member. The movement detecting device includes a rotating disc rigidly connected to and co-rotating with the inertia drive member. The impulse wrench also includes a sensing device including four Hall-element type sensors, and the disc has a rim portion which is magnetised to provide a number of magnetic poles for activating the sensors at rotation of the inertia drive member. The sensors are arranged in pairs such that the delivered signals from the sensors in each pair has a relative phase lag of 180 degrees, and the sensors of one of the pairs are arranged to deliver signals with a phase lag of 90 degrees relative to the sensor signals from the other pair.

Abstract: A method for determining the angular displacement of the output shaft (?0) of an impulse nut runner at tightening a screw joint to a predetermined final torque level (Tf) by an impulse nut runner having a motor driven impulse unit (23) with an inertia drive member (27), an output shaft (24) to be coupled to the screw joint to be tightened and an angle sensing device (35, 38) associated with the drive member (27) and arranged to deliver signals in response to the rotational movement of the drive member (27), wherein the total angular displacement of the output shaft (24) in relation to a threshold torque level (Tt) is calculated as a difference between the total angular displacement (?Dtot) of the drive member (27) as a result of a total number of delivered impulses (Ntot) and the angle of the total number of full revolutions minus one full revolution ? (Ntot?1)·360).

Abstract: An electric power tool has a motor with a stator and a rotor, an electronic module for operation control and signal and power communication, and a connector for a cable plug connecting the tool to a stationary remote control unit. The electric power tool includes an electric interface between the motor stator and the electronic module including a number of contact elements rigidly attached to the electronic module and a number of matching contact elements rigidly supported on the motor stator to enable quick plug-in between the stator and the electronic module.

Abstract: A pneumatic power tool includes a housing, a motor, a pressure air inlet passage, an exhaust air outlet passage, and an exhaust air outlet flow deflector. The exhaust air outlet flow detector includes an outlet piece with radial as well as axial outlet openings and a valve element with radial as well as axial apertures. The outlet piece and the valve element are rotatable relative to the housing as well as to each other to bring a radial opening of the outlet piece into or out of alignment with a radial aperture of the valve element (21), and at the same time to bring the axial apertures of the valve element out of or into alignment with the openings of the outlet piece, thereby shifting the exhaust outlet flow direction as desired between a radial direction and an axial direction.

Abstract: A method for determining the angular displacement of the output shaft (?o) of an impulse nut runner at tightening a screw joint to a predetermined final torque level (Tf) by means of an impulse nut runner having a motor driven impulse unit (23) with an inertia drive member (27), an output shaft (24) to be coupled to the screw joint to be tightened and an angle sensing device (35, 38) associated with the drive member (27) and arranged to deliver signals in response to the rotational movement of the drive member (27), wherein the total angular displacement of the output shaft (24) in relation to a threshold torque level (Tt) is calculated as a difference between the total angular displacement (?Dtot) of the drive member (27) as a result of a total number of delivered impulses (Ntot ) and the angle of the total number of full revolutions minus one full revolution [ (Ntot?1) . 360).

Abstract: The present invention relates to a power-wrench comprising an electrical converter-fed motor having a permanent-magnetized rotor and a stator provided with winding, the motor winding (1) comprising at least two winding parts, which independently of each other are connected and disconnected by a switch-over device (4). According to the invention, a first winding part (2) may be arranged to control the magnetic field of the motor so that the motor, having the first winding part (2) connected, is adapted for the threading-down phase of the nut driving and operates with low torque and high number of revolutions adapted to said phase, as well as that a second winding part (3) may be arranged to control the magnetic field of the motor so that the motor, having the second winding part (3) connected, is adapted for the final-threading phase of the nut driving and operates with high torque and low number of revolutions adapted to said phase.

Abstract: A nut runner mounting structure for supporting one or more nut runner spindles includes a spindle supporting base plate, and at least one support pillar extending in parallel with the spindles and secured at its forward end to the base plate and at its rear end to a mounting structure support. Each support pillar has a tube element provided with a forward end piece and a rear end piece, and a tension bolt engaging the rear end piece and the base plate to exert an axial clamping force on the tube element. The forward end piece is formed with sharp edged teeth for penetrating into and forming matching teeth in the tube element and the base plate for locking the tube element against rotation. Clamping units are attachable to the tube elements for carrying additional equipment and connecting the structure to a mounting structure support.