PORTABLE POWER WRENCH WITH TORQUE SENSOR ON DRIVE SPINDLE

摘要

A portable power wrench having a housing with a main section (10) and an exchangeable front section (11), wherein the main section (10) includes a rotation motor, and the front section (11) includes a drive spindle (15) coupled to an output shaft (21). The drive spindle (15) comprises a weak portion (26) elastically deformable by the torque transferred by the drive spindle (15) and carrying a strain gauge type torque sensor (27). The drive spindle (15) is also formed with an internal coaxially extending cavity (30) in which is supported a signal treating circuitry (28). The latter communicates with the torque sensor (27) and a contact free signal and power transferring device (35) located at an interface (A-A) between the front section (15) and the main section (10) of the housing and arranged to transfer signals and power between the drive spindle (15) and the main section (10).