US 7,455,123 B2
Hand-held power tool with a torque-limiting unit
Bruno Aeberhard, Studen (Switzerland)
Assigned to Robert Bosch GmbH, Stuttgart (Germany)
Filed on Dec. 01, 2005, as Appl. No. 11/291,832.
Claims priority of application No. 10 2004 058 807 (DE), filed on Dec. 07, 2004.
Prior Publication US 2006/0118380 A1, Jun. 08, 2006
Int. Cl. B25B 23/14 (2006.01); F16D 43/20 (2006.01); B23Q 5/00 (2006.01)
U.S. Cl. 173—178  [173/176; 192/56.61; 464/38] 17 Claims
OG exemplary drawing
 
1. A hand-held power tool, comprising a motor output shaft; a tool driver; a first and a second locking disc; a thrust member; and a torque-limiting unit with which a maximum torque transferred from said motor output shaft to said tool driver is adjustable by an operator, said torque-limiting unit including a spring system, said spring system including differently-acting spring elements generating different spring forces, wherein said spring system is held by said second locking disc and each spring element of the spring system is held between a pin of the second locking disc and a pin of said thrust member, wherein the first locking disc is connected with the second locking disc via cams, wherein said cams are built on each of said locking discs, wherein if a torque applied to the tool driver reaches a selected maximum torque level, the second locking disc is deflected against the spring system by beveled flanks of said cams, and the first locking disc can rotate against the second locking disc.