摘要 |
A torque responsive release clutch intended for a power nutrunner and comprises a driving clutch half (11) and a driven clutch half (10) coupled to each other for torque transfer by means of axially directed teeth (16, 17), wherein one of the clutch halves is axially movable between an engagement position and a release position against the action of a bias spring (13). Each one of the teeth (16) of one of the clutch halves (10) has a substantially prismatic shape and extends axially from a base portion (19) to a top portion (20) and comprises two surfaces (22, 23) which form between them a ridge (25). The base portion (19) of the tooth (16) has a radial extent from an inner diameter (d1 to an outer diameter (d2), and the ridge (25) extends from the inner diameter (d1 at the base portion (19) to the outer diameter (d2) at the top portion (20). The contact points between teeth (17) of the driving clutch half (11) and the teeth (16) of the driven clutch half (10) are arranged to travel along the ridge (25) during the release sequence of the clutch, whereby the torque coupling of the clutch is transferred via a smaller diameter at the beginning of the release sequence than at the end thereof. This means that the dynamic torque additive emanating from the inertia of the movable clutch half at the beginning of the release movement is added to a torque level that is lower than that at the end of the release sequence. |