Abstract: The impactor’s performance varies according to its work objects, and this is called its flexibility. As the existing hydraulic impactors work on the principle of distance feedback, they are restricted by the volume and machining process. The power of such impactors can only be adjusted within the range of 2~3 grade, and they have to stop working for adjustment. Consequently, neither can such impactors work efficiently nor can they adjust their performance according to the physical nature of the work objects. How to make the impactor’s performance automatically acclimatize to the environment or the different objects is an advanced study in this field. A new nitrogen-inflating impactor based on pressure feedback principle is put forward. It can estimate the work object’s nature by piston’s rebound behavior and adjust the power and frequency steplessly by flexible flow distribution system, which achieves the flexible impact. The field test shows that the new flexible impactor possesses great flexibility as regards its working time, space and environment.

Key words: Flexibility, Impact, Impactor, Rebound