Rotary tool

• Main Author: STIRM MICHAEL,LAUTERWALD MARTIN,GENSMANN STEFAN D.,HAHN NORBERT,USSELMANN ROBERT ALAN,JUNG ACHIM,BRADUS ROBERT
• Format: Patent
• Language: English
• Published: 09.11.2005
• Edition: 7
• Subjects: BLASTING; BRAKES; CLUTCHES; COMBINATION OR MULTI-PURPOSE TOOLS NOT OTHERWISE PROVIDEDFOR; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOTDIRECTED TO A PARTICULAR RESULT; COUPLINGS FOR TRANSMITTING ROTATION; DETAILS OR COMPONENTS OF PORTABLE POWER-DRIVEN TOOLS NOTPARTICULARLY RELATED TO THE OPERATIONS PERFORMED AND NOTOTHERWISE PROVIDED FOR; DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g.ARRANGEMENTS FOR COPYING OR CONTROLLING; ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HAND TOOLS; HEATING; LIGHTING; MACHINE TOOLS; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OFPARTICULAR DETAILS OR COMPONENTS; MANIPULATORS; MECHANICAL ENGINEERING; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; PORTABLE POWER-DRIVEN TOOLS; THERMAL INSULATION IN GENERAL; TRANSPORTING; WEAPONS

A power tool, g a hammer drill, has a first mode of operation in which a first set drive balls 113a are urged into engagement with drive pockets 115a of a small diameter driven gear 13c by portion 121a of actuating shaft 121. In a second mode of operation a second set of drive balls 113b are pushed radially outwardly by portion 121a into engagement with large driven gear 13d. When portion 121b of the actuating shaft 21 is radially inward of drive balls 113b the drive balls move radially inwardly disengaging with drive pockets 115d so that no drive is transmitted to drive shaft 5. In a third mode of operation the portion 21b of the actuating shaft 21 is radially inwardly of both sets of drive balls 113a, 113b both sets are disengaged from the drive pockets 115a, 115b and no rotary drive is transmitted between the driven gears 13c, 13d and the drive shaft 5. Thus the overload clutch in the first mode transmits drive to the shaft 5 below a first predetermine torque and stops drive above the first torque while in the second mode it transmits drive below a second predetermined torque and stops torque above the second torque and in the third mode the overload clutch cuts off drive to the shaft 5 in response to a mode change mechanism (126, 128, fig 11A).