A small-diameter front-end portion of a feed rod is allowed to enter into the screw hole of a nut delivered by a nut chute, and the nut is fed to an intended position by the forward movement of the feed rod. When an abnormal nut having a screw hole into which the small-diameter front-end portion cannot be inserted is delivered, the abnormal nut is prevented from being flicked by the feed rod. In order to achieve this, in a standby state, the small-diameter front-end portion of the feed rod enters a nut receiving chamber and is then stopped. On condition that the abnormal nut is received in the nut receiving chamber, if the feed rod moves forward to enter into the standby state, the abnormal nut is slightly pushed out forward from the nut receiving chamber.