PERCUSSIVE-ACTION HYDRAULIC MECHANISM Russian patent published in 1997 - IPC

FIELD: percussive-action mechanism for breaking frozen ground and rock in construction and mining industries. SUBSTANCE: mechanism has body which incorporates gas-operated energy accumulator, cocking chamber which accommodates striker with head stepped valve biased by resilient energy accumulator. Outer surface of valve and inner surface of body form together an overflow space have grooves which by their surface and stepped valve form together a labyrinth slot. Stepped valve is positioned for possible interaction with body for closing this labyrinth and creation of a pressure space. Inner surface of stepped valve and striker head create together an undervalve space which at cocking of striker communicates with pressure space through passages in valve. Overflow space is permanently connected with return line, and cocking chamber communicates with pressure line. EFFECT: high efficiency. 1 dwg