CUTTER DEVICE

The present invention discloses a cutter device having a pocket formed on a body to receive an insert and a screw hole formed in proximity of the pocket to receive a screw, clamping the insert by a deformable gripping part which is displaced by the screw wherein: the insert has a hexahedral shape, and has parallel upper and lower surfaces and parallel opposing side surfaces, one opposing pair of the side surfaces being provided with grooves extending lengthwise, the other opposing pair of the side surfaces having cutting blades on the upper and lower edges, the pocket is formed by two side walls, a backside wall, and a bottom wall, and is open forwardly and upwardly, one side wall being provided with a guide protrusion extending lengthwise and fit complementarily to one of the grooves of the insert, the other side wall being a portion of the deformable gripping part and being provided with a guide protrusion extending lengthwise to fit complementarily with the other one of the grooves of the insert, the screw has a taper portion which has a diameter increasing toward the head end, and the deformable gripping part has a neck portion which is formed by a slot traversing the screw hole inclinedly and a lower edge of the other side wall of the pocket, and is elastically displaceable so that the distance between the guide protrusions is narrowed by pressing of the taper portion when the screw is tightened.