Rotational driving tool for screwing member

摘要

A tool (1) comprising a head (4) having at least two engaging surfaces (10) for driving the screwing member by its at least partially matching shape and a device (5) for driving the head rotation. The head globally behaves as a single-piece part when the screwing member is driven in rotation. The head includes a zone (7) linking the engaging surfaces and parts (9) transmitting to the engaging surfaces a rotation force applied on the driving device. The linking zone is located between the force-transmitting parts and the engaging parts. The head is designed such that the action of the rotational driving device on the force-transmitting parts tends to deform the shape of the head so as to bring the engaging surfaces closer to each other when a rotational driving force is applied via the driving device on the screwing member. The present invention is, for example, applicable to flat open-end wrenches.