Abstract: A hydraulic braking device for testing industrial screwdrivers is arranged on a braking simulation bench, the braking device being controlled by an actuator and by a hydraulic control circuit which supplies pressure to the device on the basis of the indications of an electronic elaboration unit of the bench. Such a braking device is provided with coupling means for the screwdriver to be subjected to test and measurement transducers controlled by a processing unit, suitable for measuring the torque exerted by the screwdriver and the rotation angle, and such a device includes a memory which can be read and/or written by the bench electronic elaboration unit.

Abstract: A system for verifying proper functioning of industrial screwdrivers placed on a test bench is provided. The bench includes a plurality of hydraulic brakes, with which the screwdriver is associated, controlled by a hydraulic circuit including a pump, which withdraws the fluid from a reservoir and provides it to a pressure regulating valve, which in turn provides it to the brakes. Each brake is provided with measuring transducers connected to an electronic driver board, which also controls the regulating valve. A hydraulic distributor is present between the brakes and the regulating valve, the hydraulic distributor including solenoid valves able to select, operate and control the hydraulic pressure of each brake to which it is selectively connected. A computer communicates with the board and includes a driving program stored thereon capable of progressively increasing the braking capacity of the brakes according to a preset braking torque/brake rotation angle curve.

Abstract: Hydraulic braking device for testing industrial screwdrivers, said braking device being arranged on a braking simulation bench, said braking device being controlled by an actuator and by a hydraulic control circuit which supplies pressure to the device on the basis of the indications of an electronic elaboration unit (U) of said bench. Such a braking device is provided with coupling means (A) for said screwdriver to be subjected to test and measurement transducers (TR) controlled by said processing unit, suitable for measuring the torque exerted by the screwdriver and the rotation angle, and such a device comprises a memory which can be read and/or written by the bench electronic elaboration unit.

Abstract: A regulator for a power tool for tightening a fastener in order to unite two or more pieces into a joint. The regulator regulates the power tool when tightening the fastener such that the fastener is tightened to a predetermined target. The regulator calculates an output signal to the power tool, which output signal is based on the product of the torque exerted by the power tool on the fastener and the angle for turning the fastener about its axis. The output signal is used for tightening the fastener to the predetermined target. The regulator is also applicable to a power tool for a rivet joint.

Abstract: A drilling unit with automatic drill shaft feeding is provided. The feeding velocity can be changed by external mounting of exchangeable gearing cassettes having a desired gear ratio.

Abstract: A portable power wrench is controlled by an operation control unit and comprises a housing (10;50) with a rotation motor, a gear casing (15;55) including a gearing (18;56,57) and a drive spindle (19;60} and being releasably and/or rotatably connected to the housing via a swivel or multi-position connection, an operation parameter sensing device (22,23;68) is associated with the drive spindle (19,60). The sensing device (22,23;68) communicates with the operation control unit via a first signal transferring device (28;82) which is disposed between the drive spindle (19;60) and the gear casing (15;55), and a second signal transferring device (31;84) is disposed between the gear casing (15;55) and the housing (10;50), wherein the second signal transferring device (31;84) communicates with the operation control unit. At least the first signal transferring device (28;82) between the drive spindle (19;60) and the gear casing (15;55) comprises a contact free transfer device.

Abstract: A portable pneumatic power wrench has a housing with a handle, a motor, a pressure air inlet passage, and an outlet passage for ducting exhaust air from the motor out of the housing. An outlet unit is connected to the outlet passage and has a first outlet opening section forming a main exhaust air flow path, a second outlet opening section forming an additional exhaust air flow path, and a manually operable valve arranged to control the additional exhaust air flow path by opening or closing the second outlet opening section. The total outlet flow area of the main exhaust air flow path and the additional exhaust air flow path gives an augmented torque output of the power wrench.

Abstract: A method and a device are provided for locking the operation of a power wrench to the location of an unacceptably tightened screw joint or object with a sensor for at least one tightening parameter. A position sensing system is provided for indicating continuously the position of the power wrench during tightening operations, and a control unit includes a unit for comparing obtained tightening parameter values with predetermined limit values and to provide an OK or a NOK signal in response to those limit values being passed or not for each screw joint. A locking device is provided to lock the power wrench operation to the very position of the screw joint or the object for which a NOK signal has been issued until the unacceptably tightened screw joint has been attended to and the NOK signal is removed.

Abstract: A portable power wrench of an angle type includes an elongated housing with an angle drive head and a rear handle and supports a motor. The power wrench also includes a manually operated power control device including a main power control trigger located at the rear handle and an auxiliary power control trigger located at the angle drive head. The motor as well as the main trigger and the auxiliary power control trigger are connected to a programmable control unit in which there are stored operation parameter sets suitable for a screw joint running down phase and a final tightening phase, respectively. The auxiliary power control trigger is arranged to activate the running down parameter set only, whereas the main power control trigger is arranged to activate the final tightening parameter set.

Abstract: A pneumatic impulse wrench for tightening screw joints includes a housing with a pressure air inlet passage, an exhaust air outlet passage, a rotation motor, a hydraulic impulse generator, and is connected to a stationary programmable control unit. The impulse wrench also includes a torque indicating mechanism connected to the control unit for feeding back electric signals responsive to the output torque of the wrench, an electromagnetically activated inlet valve arranged in the air inlet passage, and an electromagnetically activated exhaust valve which controls the exhaust air flow from the motor. The exhaust valve is a proportional valve activated by a linearly operated electromagnetic actuator and arranged to continuously adapt the exhaust air flow and, hence, the motor power to the characteristics of the actual screw joint being tightened in response to feed back signals from the torque indicating mechanism and in accordance with a programmed tightening strategy.

Abstract: A portable power drill includes a housing, a drilling implement carrying drive spindle, and a drive motor for rotating and axially feeding the drive spindle. The drive spindle is rotatively and axially displaceable relative to the housing and connected to the drive motor via angle gears, a feed mechanism and two bevel gears supported on the drive spindle. The drive motor is drivingly connected to the drive spindle via a belt drive transmission, a feed shaft, and an angle gear including an axially locked but rotative nut piece. The feed shaft is located in parallel with and coupled to the drive motor via a transmission and drivingly connected to said nut piece. The drive motor is an electric motor controlled and monitored by a programmable control unit.

Abstract: A pneumatic motor unit includes a housing with an air inlet passage, an exhaust air outlet passage, and a rotation motor which generates a pulsating exhaust air outlet flow. The motor unit further includes a voltage depending device which communicates signals in response to at least one of an actual motor condition and operation parameter values, and a voltage generating section which is connected to the voltage depending device and which includes a piezoelectric element provided in the exhaust air outlet passage and arranged to be activated by pressure pulses of the pulsating exhaust air outlet flow from the motor. The piezoelectric element is tongue shaped and rigidly secured at one end, and is arranged to be swung in a two-way movement relative to a central rest position to thereby generate an alternating current voltage.

Abstract: A hand held machine for grinding and like operations, includes a housing, a motor mounted in the housing and which rotates an axle connected to a tool carrying mechanism, and a front bearing arrangement provided between the housing and the axle, including a front bearing, and a vibration insulator which is resilient to radial displacement of the axle. The vibration insulator includes at least one resilient element located between the housing and the front bearing. The machine further includes an adjustment mechanism interacting with the at least one resilient element for adjustment of the resilience of the resilient element.

Abstract: A portable power drill comprises a housing, a drilling implement carrying drive spindle, and two individually powered and controlled motors for rotating and axially feeding the drive spindle. The drive spindle is rotative and axially displaceable relative to the housing and connected to the drive and feed motors via angle gears including two bevel gears supported on the drive spindle. The feed via an axially locked but rotative nut piece and an external thread on the drive spindle, whereas the drive motor is drivingly connected to the drive spindle via longitudinal keyways on the drive spindle and mating splines in one of the bevel gears. The drive motor and the feed motor are electric motors controlled and monitored by a programmable control unit.

Abstract: An ultrasonic measurement device and method in which an ultrasonic transducer is acoustically coupled to an object to be measured by a resilient material contact layer. The transducer transmits a plurality of consecutive ultrasonic transmit signals into the object being measured, the transmit frequency of each of the plurality of transmit signals being distinct from the frequency of the other transmit signals of the plurality of transmit signals. Signal echoes of the transmitted signals are received, and based on the received signal echoes, at least one transmit frequency to be used for ultrasonic measurement of the object is selected.

Abstract: A screw fastener testing method for verifying the status of a previously tightened screw fastener with respect to installed torque and actual torque growth per angle of rotation properties includes applying an increasing tightening torque on the fastener, measuring the torque magnitude at the start of rotation, of the fastener, measuring the rotational movement of the fastener after the start of rotation, calculating the torque growth per angle of rotation for a certain predetermined test interval of rotation from the start of rotation, comparing the torque magnitude indicated during rotation and the calculated torque growth per angle of rotation during the test interval of rotation with predetermined reference values (Tstart, KR) or (TE, KP), respectively, characteristic for the actual fastener when tightened to a desired target torque level, and approving or disapproving the fastener status in view of the reference values.

Abstract: A portable power tool having a housing with a rotation motor for powering a working implement, wherein sensors are provided to indicate the motor speed and the power supply, and a programmable evaluation unit is arranged to compare indicated speed and pressure values with stored limit values, and to accumulate the total operation time of the power tool and compare that with preset time limits for tool service intervals, and an optical information unit is provided on the housing to indicate whether those stored limit values have been reached.

Abstract: A power tool has a housing, a pneumatic rotation motor supplied with pressure air via an inlet passage, an outlet passage connecting the motor to an exhaust air discharge, and a speed governor for controlling the pressure air flow through the inlet passage responsive to the motor speed. The outlet passage includes a first outlet duct and a second outlet duct extending in parallel between the motor and exhaust air discharge, and an exhaust valve which controls exhaust air flow through the second outlet duct. The exhaust valve is spring biased toward a closed position and shifted to an open position by an activator which is exposed to the air pressure in the inlet passage downstream of the speed governor and which shifts the exhaust valve to the open position at pressure levels above a certain pressure level in the inlet passage downstream of the speed governor.

Abstract: A speed control device is provided for a pneumatic power tool which includes a housing with a pressure air inlet, an output spindle, and an air turbine with a turbine wheel drivingly connected to the output spindle. Nozzles are arranged for directing motive air onto the turbine wheel. The speed control device includes a valve unit for controlling pressure air flow through the nozzles in response to a speed responsive parameter. The plurality of nozzles are divided into n separate nozzle groups having individual air feed through individual air feed passages (n is an integer, n>1). The valve unit is capable of being actuated into n states for controlling air feed to the n nozzle groups, whereby for each subsequent state, x (1?x?n, x is an integer) air feed passages are connected to the pressure air inlet such that nozzle groups 1 to x are fed with air.

Abstract: A power wrench including a housing, a rotation motor, a reduction gearing connecting the motor to an output shaft, and a separate gearing casing which is rotatively and detachably mounted on the housing and supporting the output shaft. The reduction gearing is divided into a first gearing stage located in the housing and a second gearing stage located in the separate gearing casing. The first gearing stage and the second gearing stage are interconnected via an intermediate spindle, and the motor is connected to the first gearing stage via a hollow drive shaft surrounding the intermediate spindle and an angle gear. A torque sensor is associated with the first gearing stage in the form of strain gauges mounted on an elastically deformable sleeve connecting a ring gear of the first gearing stage to the housing.