DOWN-THE-HOLE SHOCK MACHINE Russian patent published in 1997 - IPC

FIELD: drilling technics. SUBSTANCE: invention relates to down-the-hole machines for shock-rotary boring holes and may find use in exploration, groundwater hydrology, and mining. Shock machine admits energy carrier in the form of optionally aerated liquid or compressed air whose energy is transformed into shock pulses affecting borehole bottom. Machine includes: adapter with pipe; casing with barrel; hammer with axial through channel separating casing hollow into forward- and back-stroke working chambers; system for distributing energy carrier to working chambers comprising stepped feed-discharge valve, great step of which faces adapter and which, with casing and adapter, forms over-valve cavity, while lower platform of valve faces forward-stroke chamber; feed, drain, discharge, and control lines. Hammer is of stepped type and has head and rod restricting back-stroke chamber constantly being connected with over- valve cavity through barrel channels, while lower platform of valve restricts forward-stroke chamber. Optimal proportion between steps of valves and hammer is observed to provide reliable start and efficient operation of machine. EFFECT: increased efficiency caused by minimum energy consumption at high operation power. 2 dwg