To use an automatic tool exchanging device even in a small space such as a comb tooth type cutlery table with a structure made as simple as possible.

A slide 3 is placed on a lathe bed in a slidable manner in X and Z axial directions and a slider 12 is placed on a cutlery table 4 fixed to the slide 3 in a slidable manner in the X axial direction, while a pivot 14 is protruded from the front end of the slider 12 to the oblique front making an arm 15, which is curved perpendicularly downward and horizontally backward, capable of swivelling. The arm 15 is composed so that it can deliver edge tools 5 between the cutlery table 4 and a tool magazine 17, and the positions of the two edge tools 5 are exchanged by the pivot swivelling at the position where the silder 12 slides and does not interfere with the arm 15.