AIR-OPERATED IMPACT DEVICE Russian patent published in 2001 - IPC

FIELD: mining and construction industry; applicable in percussive driving into grounds of pipes and other rod-shaped members. SUBSTANCE: air-operated impact device includes hammer with stepped cavity, step bushing engaged with hammer, entering said cavity and separating stepped cavity from ambient atmosphere by movable conjugation with hammer surface, and separating the cavity into chambers of working and idle strokes, and supplying channel made in step bushing. Hammer stepped cavity in working chamber is blind and movable conjugation with hammer surface separating the stepped cavity from ambient atmosphere is made only between hammer surface in smaller step of this cavity and surface of bushing step engaged with it. EFFECT: higher economic efficiency. 6 cl, 3 dwg