Abstract: An axial flow compressor including one or more axially spaced stator sections (14) each having a circumferential array of guide vanes (15), and one or more rotor section (12, 16) each having a circumferential array of rotor blades (13, 17; A, B), and between successive rotor blades (A, B) there are formed flow paths and between the stator and rotor sections there are provided axial gaps (22, 23, 24) of a diverging configuration so as to form in each flow path a diffusion region (C) which extends from a narrowest cross section (a2) of the flow path located at a certain distance upstream of the leading edge of a second rotor blade (B) to a wider cross section (a3) located approximately at the leading edge of the second rotor blade (B), wherein each flow path has a transition region (D) of a substantially non-increasing cross sectional area extending from the wider cross section (a3) to the trailing edges of the rotor blades (A, B).

Abstract: A compressor unit intended for delivering a pressurised gaseous medium at a varying outlet flow volume to a consumer with varying load demands and comprises one or more rotors (K; 10, 11) forming one or more compressor stages and arranged to operate continuously at high speed thereby delivering a certain outlet flow volume, a drive motor (M; 19), a drive line assembly (N; 17, 18) mechanically coupling the compressor rotor or rotors (K; 10, 11) to the drive motor (M; 19), and a waste flow circuit connected to the outlet end of the compressor stages and incorporating at least one power recovery turbine (TR; 22, 23) mechanically coupled to the drive line assembly (N; 17, 18), and one or more valves (V; 25, 34, 35) controlling the waste flow through the waste flow circuit in response to the actual load demand, wherein the power recovery turbine or turbines (TR; 22, 23) are arranged to deliver power back to the drive line or drive lines (N; 17, 18) at consumer load demands smaller than the certain outlet flow volu

Abstract: An oil seal for sealing off a fast rotating shaft (10) relative to a housing (11) comprises a first seal element (15) mounted on the shaft (10), a second seal element (18) resiliently mounted in the housing (11), both seal elements (15, 18) having cooperating contact surfaces (25, 26), and a spring (22) acting on the second seal element (18) to provide an axial contact pressure between the contact surfaces (25, 26). The contact surfaces (25, 26) of the seal elements (15, 18) are made of materials of different hardness, and the one consisting of the hardest material is formed with one or more circular ribs (27a-c) disposed concentrically with the shaft (10) and intended to cut mating circular grooves in the other seal element contact surface (25) during a running-in period.

Abstract: A pneumatic rotation grinder comprises a housing (10) with a throttle valve controlled air inlet passage, a rotation motor drivingly connected to an output shaft (12) intended to carry a grinding tool, a safety guard (17) adjustably supported on the housing (10) in a coaxial disposition relative to the output shaft (12), and a lock device (26-28, 33-38) for arresting the safety guard (17) in desired angular positions relative to the housing (10). The lock device (26-28, 33-38) comprises both a latch (26-28) for positive coupling by engagement of teeth (26, 28) of the safety guard (17) relative to the housing (10), and a pressure air activated clamping device (33-38) for frictional arresting of the safety guard (17) relative to the housing (10).

Abstract: A pneumatic turbine, comprising a turbine wheel (13) with a peripheral row of blades (14) and a stator housing (10) having nozzles (11) for directing motive air at high speed onto the blades (14) to rotate the turbine wheel (13), an exhaust passage (15) located downstream the turbine wheel (13), and a particle escape passage (20) located on the same side of the turbine wheel (13) as the air nozzles (11) to drain from the turbine harmful particles and, thereby, avoid a blasting effect of such particles on the turbine wheel blades (14).

Abstract: A speed governor for a pneumatic power tool which comprises a housing (10) with pressure air supply means (16-18) and an air turbine (20) including a turbine wheel (22) drivingly coupled to an output spindle and a number of air nozzles (25) for directing motive pressure air onto the turbine wheel (22), wherein the speed governor comprises a flow controlling valve element (43) associated with an activation piston (44) for adjusting the valve element (43) in response to a control pressure obtained in a pressure sensing opening (34) located opposite an idle running nozzle (28) downstream of the turbine wheel (22).

Abstract: A portable power grinder comprises a housing (11), a rotation motor (10) with a rotor (13) having a rear end portion (27) extending out of the motor (10), an output shaft (22) which is drivingly coupled via a reduction gearing (23) to the rotor shaft (13) and intended to carry a grinding tool, and a speed governor (18) for providing a constant motor speed. The reduction gearing (23) comprises a gear (24) integral with the rotor shaft (13) and another gear (25) integral with the output shaft (22). Alternative rotor shafts (13) with gears (24) of different sizes may replace each other for obtaining different gear ratios and different output speed levels, and the length of the rear end portion (27) of the rotor shafts (13) varies with the size of the integral gear (24). The housing (11) has a detachable lid (15) carrying the speed marking (2) of the tool and having an internal projection (28) of a size directly related to the speed level readable on the speed marking (21).

Abstract: An overspeed safety device for a pneumatic rotation motor comprises a housing (10, 18) and a valve element (28) which is located in a bore (27) in the housing (10, 18) and which by a trip device (29, 31) is locked in a normally open position and arranged to block at least the main part of the air supply to the motor when shifted to a closed position, and an activating device (37, 38) coupled to a rotating part (14) of the motor and arranged to be shifted by inertia forces from a normal rest position to an active position at a predetermined motor speed level. The trip device (29, 31) comprises an open spring wire lock ring (29) pretensioned toward a closed condition and located in a groove (30) in the valve element (28), and a holding device (31) normally located between the ends of the lock ring (29) to maintain the lock ring (29) in an expanded condition in which its outer diameter exceeds the inner diameter of a shoulder (32) in the bore (27).

Abstract: A vibration damped hand held rotary grinding machine comprising a housing (10), a rotation motor (11), an output shaft (13) drivingly coupled to the motor and having a mounting (14) for attachment of a grinding wheel (15), two handles (17, 18) rigidly mounted on the housing (10) and extending in right angles relative to the output shaft (13) as well as to each other, and a sector-shaped non-resilient safe guard (19) which is rigidly attached to the housing (10) and surrounding partially the grinding wheel (15) and which has an arc-shaped rim portion (20) encircling partially the grinding wheel circumference. Vibration damping inertia elements (22, 23, 24) are rigidly attached to the safe guard (19) rim portion (20) and to the outer extremities of the handles (17, 18) such that the moment of inertia of the machine is substantially increased as is the vibration force absorption.

Abstract: A rotary valve type quick coupling for interconnecting two pressure medium conduits comprises a coupling unit (10) including a casing (14) and a spherical rotary valve element (18) formed with a socket (27), and a tubular connector nipple (12) adapted to be guidingly received in the socket (27). An elongate aperture (32) is provided in the casing (14) which permits the connector nipple (12) to be introduced into the valve element socket (27) and to be rotated conjointly with the valve element (18) between a connect/disconnect position and a connected position. A transverse annular shoulder (46) on the nipple (12) is arranged to engage a guide surface (45) on the casing (14) to guide the nipple (12) and the valve element (18) as they occupy the connect/disconnect position.

Abstract: A pneumatic power wrench comprising a housing (10), a rotation motor drivingly connected to an output spindle (11), a pressure air supply passage (22, 24) in the housing (10) connecting the motor to a pressure air source and a manually operable throttle valve (17) disposed in the air supply passage (22, 24) to control the pressure air supply to the motor. An adjustable pressure regulator is arranged in the air supply passage (22, 24) upstream of the throttle valve (17) to provide a desired constant air supply pressure to the motor. The pressure regulator comprises a spring biassed relief valve (32-34) which via a venting passage (42) communicates with the exhaust passage (16) of the tool upstream of a flow restricting silencer (18) mounted therein.

Abstract: A pneumatic power tool for tightening screw joints includes a primary motor 11 for a high speed running down sequence, a secondary motor 12 for a high torque final tightening sequence, a coupling gearing 18 providing a high ratio gearing for the secondary motor 12, a gearing of a substantially lower ratio for the primary motor 11 and a one-way clutch 30 by which the secondary motor 12 is automatically engaged at decreasing tightening speed. An air supply valve 33 substantially reduces the air consumption of the tool by keeping the air supply to the secondary motor 12 shut off until a certain degree of tightness in the joint is obtained, after which the valve 33 is opened and the secondary motor 12 is energized.

Abstract: A pneumatic power tool for tightening screw joints comprises a primary motor 11 for the high speed running down sequence and a secondary motor 12 for the high torque final tightening sequence. The tool includes a coupling gearing 18 providing a high ratio gearing for the secondary motor 12, a gearing of a substantially lower ratio for the primary motor 11 and a one-way clutch 30 by which the secondary motor 12 is automatically engaged at decreasing tightening speed. An air supply valve 33 is employed to substantially reduce the air consumption of the tool by keeping the air supply to the secondary motor 12 shut until a certain degree of tightness in the joint is obtained which by the supply valve 33 is experienced as an increased back pressure from the primary motor 11. At a back pressure corresponding to the predetermined certain degree of tightness in the joint the valve 33 is opened and the secondary motor 12 is energized.

Abstract: A pneumatic power tool for tightening screw joints includes a primary motor 11 for the high speed running down sequence and a secondary motor 12 for the high torque final tightening sequence. The tool includes a coupling gearing 18 providing a high ratio gearing for the secondary motor 12, a gearing of a substantially lower ratio for the primary motor 11 and a one-way clutch 30 by which the secondary motor 12 is automatically engaged at decreasing tightening speed. An air supply valve 33 is employed to substantially reduce the air consumption of the tool by keeping the air supply to the secondary motor 12 shut off until a certain degree of tightness in the joint is obtained, after the valve 33 is opened and the secondary motor 12 is energized.A reduction gearing 19 is supported in a casing 90 which is rotatively connected to the tool housing 10 and provided with a laterally extending torque reaction bar 92.