To meet rapid progress of industrial development machining techniques also advance constantly to produce finer finished or semi-finished products. The fabrication precision of machinery depends on many factors, such as precision of tools, operation precision of the machinery, fabrication environment, and coupling and holding steadiness of the machinery and tools. One set of machine usually can hold different types of tools alternately to achieve different fabrication results (such as by changing the tools of varying sizes). After each tool changing, a calibration procedure has to be performed (because movements occur during tool changing). This involves a tedious process. Both the chuck and tool have to be removed from the machine and installed again. Fabrication tolerances and errors are bound to happen. To remedy this problem, many techniques have been proposed in prior art. For instance, R.O.C. patent No. M253434 entitled “Detachable chuck” discloses a structure mainly including a cutter stem with an axial conical cavity extended inwards from one end in a tapered manner, a holding member with a conical portion at one end and a coupling portion at the other end and a fastening member coupled on the holding member from outside and screwed on the cutter stem. The conical portion has an inclined peripheral surface formed at an angle the same as that of the conical cavity of the cutter stem, and is held in the conical cavity. The coupling portion has a central hole to hold a cutter under heating. Due to the cutter is held under heating, replacement of the cutter is troublesome. There are still rooms for improvement.