C & E. Fein Gmbh & Co.

Wolfgang Schreiber

Manfred Ludwig

Manfred Fink

Ewald Hald

Heinrich Henssler

Klaus M Junginger

Guenter Kloss

A screwdriver is disclosed, comprising a removable depth stop which selectably either, when equipped with the depth stop, allows noiseless shutoff or, with the depth stop removed, allows torque-dependent shutoff, without any chattering occurring when the machine continues to run. To this end, an adjustable torque-dependent release clutch is combined with an entrainment clutch of known type, which is additionally preceded by a disconnect clutch, a locking means being provided in order to hold a throwout ring, which forms one of the two elements of the disconnect clutch, in a predetermined position under load. In this way, noiseless operation is ensured after release, both when working with the depth stop and in the case of torque-dependent shutoff, with the depth stop removed.

Power-driven screwdriver with removable depth stop

A motor-driven machine with variable torque setting feature, especially a screwing machine with a torque-controlled switching-off feature, has a shaft which is driven by a motor via a transmission for driving a tool, and a setting ring for presetting a torque at which the shaft is to be disconnected from the transmission and/or the motor will be switched off. In order to enable approximately identical torque curves to be achieved for hard and for soft screwing applications, a clutch with a variable tripping torque is provided whose tripping torque can be adjusted via an indexing ring, which latter can be adjusted together with the setting ring.

Motor-driven screwdriver with variable torque setting for equal torques

A motor-operated tool is provided for tool sockets revolving about an axis, in particular for drills or spanners. The tool comprises a tool head containing a drive spindle. The drive spindle comprises a driving opening for a drive shank of the tool socket and a plurality of ball elements for engaging a part of the drive shank to lock it in the driving opening. The ball elements preferably are adapted to lock the drive shank in the driving opening automatically and to be released by a suitable mechanism. The tool socket is designed as a drill chuck and is provided with key elements for actuating the mechanism.

Motor-operated tool

To improve a power-operated screwing tool machine comprising a drive arranged in a housing, a screwing tool and a switch-off means for the screw-in depth including a depth stop held on the housing for fixing a screw-in depth and a clutch arranged between the drive and the tool drive shaft and transferrable by axial displacement of the tool drive shaft from a position of rest in the direction of the drive into a working position, the clutch comprising a clutch element driven by the drive, a clutch element connected to the tool drive shaft and an intermediate clutch element arranged between these clutch elements, with the intermediate clutch element forming with a first one of the clutch elements an entrainment clutch and with the second clutch element a release clutch, such that in addition to a switch-off means for the screw-in depth, the screwing tool machine comprises a switch-off means for the screw-in torque, it is proposed that the switch-off means for the screw-in depth be adapted to be switched over into a switch-off means for the screw-in torque which integrates the release clutch as torque-limiting element.

Screwdriver with switch-off means for screw-in depth and screw-in torque

A motor-driven machine with variable torque setting includes a motor, a planetary gearing driving a work spindle and a rotatably mounted internal gear actuating a motor de-energizer against the action of a spring force when a settable limit torque is exceeded. To achieve a compact design, a torsion spring element extending in the axial direction alongside the planetary gearing is provided for generating the spring force. The torsion spring element carries a swivel element at one end which engages a cam on the internal gear and is held at an opposite end in a support so that the swivel element can swivel out of an initial position against the action of the force of the torsion spring element to de-energize the motor.

Machine with variable torque setting

An electric tool with a source of power that is independent of the line and with a transmission housing or motor housing that is also designed to function as a grip, with another grip merging into one side of it. To position the center of gravity such that the tool will be easier to handle and to allow the operator to continue working when one battery pack goes dead, attachments for battery packs are provided at the end of each grip.

Electric tool with source of power independent of the line

In motor-operated machines, especially portable electric tools, it is essential to prevent an impermissibly high torque on the driveshaft or operating spindle. This is attained by means of a torque-disengagement mechanism. An especially elegant, compact, precisely responsive torque-disengagement mechanism is attained by mounting one of the two bearings for a driveshaft in the machine housing or similar structure in such a way that it can move across the longitudinal axis or radially far enough to initiate a switching procedure. The bearing is secured in an initial position by means of an opposing force. The position represents both the zero position for the switching procedure and the correct position of the axis of the driveshaft during operation. If the machine includes a means of varying the torque, the power of the opposing force can be adjusted and maintained either continuously or discontinuously. The opposing force is generated in a practical way by a spring, specifically either by a compact but still powrful stack of cup springs or by a torque rod, both requiring little space.

Portable electric tool with variable torque

A clutch for power screwdrivers. It has a transmission, an adjustable bit stop, and a drive shaft. It also has a cogwheel with cams on one face and a clutch disk with catches on one face mounted on the drive shaft. The object is a low-noise, wear-resistant clutch. The drive shaft is in one piece. An intermediate disk with catches on one face and cams on the other face is positioned between the cogwheel and the clutch disk. A spring mechanism is positioned between the cogwheel and the intermediate disk.

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Stuttgart, Germany

Wolfgang Schreiber