| 摘要 |
An electronic click wrench comprises a handle (1) for applying torque through a shaft (2) to a working head (3). The shaft (2) includes torque sensing means (10, 11) for calculating the torque applied to a workpiece by the working head (3), and a trigger mechanism (30, 40, 50) for sending a haptic feedback to a user by triggering a small movement of the handle (1) relative to the working head (3) when a set point torque is reached. The trigger mechanism comprises a permanent magnet (31, 41, 51) that is normally anchored by magnetic attraction to a pole piece (12) so as to resist separation when a force is applied through the handle (1), and an electromagnetic means (34, 44, 55) actuable to reduce or cancel that magnetic attraction so as to permit separation of the pole piece (12) and permanent magnet (31, 41, 51), thus generating the haptic feedback. Operation of the electromagnet (34, 55) may oppose the flux of the permanent magnet (31, 51) through the pole piece (12). Alternatively operation of the electromagnet (44) may divert the flux (43) of the permanent magnet (41) away from the pole piece (12). |
