Abstract: An impulse wrench comprises a pneumatic rotation motor (12), a hydraulic torque impulse generator (13) provided with an impulse magnitude responsive actuator (17), a linear movement responsive electric signal producing device (25) located at the rear end of the motor (12), a movement transferring push rod (21) extending through an axial bore (22) in the motor rotor (16) and interconnecting the actuator (17) and the signal producing device (25), an electrically activated motive air shut-off valve (31) disposed concentrically with the signal producing device (25), and an external process controlling and monitoring unit (40) connected to the signal producing device (25) and the shut-off valve (31) and arranged to compute and compare received signals with predetermined values and to initiate shut-off of the power supply (31) as a desired tightening condition is reached.

Abstract: A hydraulic torque impulse generator includes a motor driven drive member (10) with a fluid chamber (23), an output spindle (11) extending into the fluid chamber, two diametrically opposite seal elements (12, 13) movably supported in axial slots (32, 33) in the output spindle for sealing cooperation with seal lands (24, 25) on the fluid chamber wall, axially extending seal ribs (27-30) on both the fluid chamber wall and the output spindle, and a cam spindle (40) coupled to the drive member (10) and extending into a coaxial bore (34) in the output spindle for moving the seal elements outwardly towards the fluid chamber wall in two relative angular positions between the drive member and the output spindle. The cam spindle (40) has two diametrically opposite and differently shaped cams (41, 42) for alternative engagement with high and low lift cam followers (45-50) on the seal elements (12, 13).

Abstract: A hydraulic torque impulse generator comprises a hollow drive member (21) connected to a rotation motor (16) and comprising a fluid chamber (24) with axially extending seal lands (35, 36) and seal ridges (40, 41) on its peripheral wall for sealing cooperation with radially movable seal elements (33, 34) and axially extending seal ridges (38, 39) on an output spindle (18, 22) to divide the fluid chamber (24) into high pressure compartments (H.P.) and low pressure compartments (L.P.) during short intervals of the relative rotating between the drive member (21) and the output spindle (18, 22). The fluid chamber (24) is defined also by two opposite end walls (25, 28), one (25) of which comprises an annular, nonresilient contact element (37) which is axially displaceable between an active seal position in which it is urged against the seal elements (33, 34) and shoulders (43, 30) on the spindle portion (22) and the fluid chamber wall (20), respectively, and a rest position.

Abstract: A hydraulic torque impulse generator uses a dual piston arrangement to provide impacts to a rotative anvil and automatic shut-off and control apparatus for limiting the pressure without reversing the direction of the driving clutch cage, a pressure venting arrangement permitting one impact per revolution.

Abstract: A torque impulse delivering power tool having an automatic power shut-off (28) and comprises a drive unit (15) including a rotor (16), a power supply (24) connected to the drive unit (15), a power controller (23) included in the power supply (24), an output shaft (20), and a hydraulic impulse clutch (19) coupling intermittently the drive unit (15) to the output shaft (20), which impulse clutch (19) comprises a drive member (18) drivingly connected to the drive unit rotor (16). A retardation responsive trip device (28) includes an inertia influenced activation member (29) which is mounted on a pivot pin (30) on the drive member (18) for movement about an axis substantially parallel to the rotation axis of the drive member (18) and which is arranged to activate a latch (40-44) by which the power controller (23) is shiftable from an open position to a closed position as a certain retardation magnitude is reached in the drive member (18).

Abstract: A hydraulic torque impulse generator comprises a drive member (10) connected to a rotation motor and including a cylindrical fluid chamber (12) partly defined by a circumferential wall (14), and an output spindle (13) rotatably supported in coaxial relationship with the drive member (10) and having a rear portion (15) extending into the fluid chamber (12). The rear spindle portion (15) has two radial slots (18, 19) each supporting a radially movable seal element (21, 22) for sealing cooperation with seal lands (23, 24) on the fluid chamber wall (14). First seal ridges (25, 26) are provided on the rear spindle portion (15) for sealing cooperation with second seal ridges (28, 29) on the fluid chamber wall (14), thereby dividing the fluid chamber (12) into two high pressure compartments (H.P.) and two low pressure compartments (L.P.) during two short intervals of each revolution of the drive member (10) relative to the output spindle (13).

Abstract: A hydraulic torque impulse generator comprising a rotationally driven drive member (10; 50), a hydraulic fluid chamber (16; 51) confined in the drive member (10; 50), an output spindle (18; 53) having a rear impulse receiving portion (17; 52) extending into the fluid chamber (16; 51), at least two radially slidable vanes (23, 24; 58, 60) carried by the rear spindle portion (17; 52) and cooperating with corresponding seal portions (25, 26; 62, 63, 64) on the fluid chamber wall, axially extending seal ribs (29, 30; 65, 66, 67) on the fluid chamber wall and corresponding axially extending seal ribs (27, 28; 68, 70) on the rear spindle portion (17; 52). Simultaneous sealing cooperation is obtained more than once during each revolution of the drive member (10; 50) relative to the output spindle (18; 52), whereby the fluid chamber (16; 51) is momentarily divided into at least two high pressure compartments (H.P.) and at least two low pressure compartments (L.P.).

Abstract: A hydraulic torque impulse generator comprises a drive member (10) drivingly connected to rotation motor and including a cylindrical fluid chamber (11) which is partly defined by a circumferential wall (23) of a non-constant radius, an output spindle (12) rotatably supported in a coaxial relationship with said drive member (10) and comprising a rear portion (13) which extends into said fluid chamber (11) and which has two radial slots (29, 30) in which seal rollers (27, 28) are radially movable. The drive member (10) has a rear end wall (20) which is formed with a forwardly extending hub portion (25) on which is rigidly attached a cam element (26) for positive engagement with the seal rollers (27,28) to move the latters outwardly toward the fluid chamber wall (23) during rotation of said drive member (10) relative to said output spindle (12).

Abstract: A hydraulic torque impulse tool, comprising an inertia drive member (10;110) which is rotated by a motor and which includes a fluid chamber (19;119), and a seal and torque transmitting mechanism (30;130) which is arranged to divide the fluid chamber (19;119) into two compartments (38, 39; 138, 139) during a short interval of the relative rotation between the drive member (10;110) and the output spindle (11;111). A leaf spring valve (72; 171, 172) is arranged to control the flow through a bypass passage (70;170) interconnecting the two fluid chamber compartments (38, 39; 138, 139). The leaf spring valve (72;171, 172) which by its shape is pretensioned toward open condition automatically occupies the open condition as the difference in pressure between the fluid chamber compartments is low and a closed condition as this difference exceeds a certain level.

Abstract: A hydraulic torque impulse tool, comprising an inertia drive member (10) which is rotated by a motor and which includes a fluid chamber (19), and a seal and torque transmitting mechanism (30) which is arranged to divide the fluid chamber (19) into two compartments (38, 39) during a short interval of the relative rotation between the drive member (19) and the output spindle (11). An annular leaf spring valve (82) is arranged to control the flow through a bypass passage (70,81, 79) interconnecting the two fluid chamber compartments (38, 39). The leaf spring valve (82) which by its shape is pretensioned toward open condition automatically occupies the open condition as the difference is pressure between the fluid chamber compartments (39, 39) is low and a closed condition as this difference exceeds a certain level.

Abstract: In a hydraulic torque impulse tool having a power rotated inertia drive member (10; 110) and a hydraulic fluid chamber (19; 119) a piston (30; 130) is supported in the fluid chamber (19; 119) for reciprocating movement in a plane transverse to the rotation axis of the drive member (10; 110). The piston (30; 130) and the output spindle (11; 111) are provided with cam means (42, 43, 44; 142, 143, 144) by which the piston (30, 130) is reciprocated in the fluid chamber (19; 119) at relative rotation of the drive member (10; 110) and the output spindle (11; 111) of the tool. The piston (30; 130) and the fluid chamber (19; 119) have seal means (31, 28; 131, 128) by which one fluid chamber compartment (38; 138) is sealed off from another (39; 139) during a certain portion of each piston stroke, thereby accomplishing an instantaneous pressure build-up in one of the fluid chamber compartments.

Abstract: A bolt for transmitting axial load having a head provided with a weakening slot for promoting elastic deformation of the head in response to the axial load magnitude. On the head there is a pair of measure points located at each side of the slot in or adjacent the free end surface of the head at a distance between them that decreases at increasing axial load on the bolt. The bolt head also comprises a pair of reference points located either in the same axial plane as the measure points but in a direction perpendicular to the latters or in a plane axially spaced from that of the measure points adjacent the bottom of the weakening slot. The location of the reference points is such that the relative distance between them remains unaffected by the deformation of the bolt head and thereby the axial load transmitted by the bolt.

Abstract: A device for tightening screw joints, comprising a motor, a torque responsive slip clutch and an output shaft, said slip clutch comprising a coil-type friction spring which by one of its ends positively engages one of the clutch halves and which, due to torsional pretensioning, engages the other clutch half by a radially acting friction grip. An adjustable auxiliary torsion spring is arranged in parallel with said friction spring in such a way as to increase or decrease the friction grip of the latter relative to said other clutch half and, thereby, increase or decrease the output torque level of the device. The device includes an adjusting mechanism for setting the torsion load of said auxiliary torsion spring.

Abstract: A device for tightening screw joints, comprising a pressure fluid motor, an overload friction type slip clutch, a pressure fluid shut off valve and a release mechanism for initiating closing of said shut off valve at slipping of said overload clutch. The release mechanism comprises a female member associated with one of the slip clutch halves and a male member associated with the other of the slip clutch halves, and when aligned with said female member receivable thereinto. The release mechanism also comprises a guide means for urging against a biasing means said male member into alignment with said female member upon relative rotation of the slip clutch halves.

Abstract: A rotary pneumatically powered tool comprising a housing, a motor assembly mounted in the housing and comprising a pneumatic motor for rotating an output shaft, and vibration absorbing mounting means for supporting and vibration insulating the motor assembly relative to the housing. The vibration absorbing means comprises a resilient connection piece for cramping the motor assembly axially in the housing and for interconnecting air passages in the motor assembly and the housing so as to enable communication of pressure air to and from the pneumatic motor of the motor assembly.