REVERSIBLE PNEUMATIC DEVICE OF PERCUSSIVE ACTION TO FORM HOLES IN GROUND Russian patent published in 2004 - IPC

FIELD: construction equipment, laying of underground service lines. SUBSTANCE: proposed device has body housing striker, air distribution mechanism coming in the form of two-step branch pipe anchored in tail part of body and placed in space of striker with its step of larger diameter that has windows is side surface, collar and protrusions in its space where spring-loaded bushing is located. Bushing has windows in its side surface and barrier with window and rests for interaction with protrusions in larger step of two-step branch pipe. Body, striker and two-step branch pipe form front and rear working chambers, rear chamber communicates with compressed air source constantly and front chamber - periodically. Spring-loaded bushing has two steps so that its step of smaller diameter embraces smaller step of two-step branch pipe possessing windows shut off by smaller step of above-mentioned spring-loaded bushing. Two-step branch pipe and spring-loaded bushing form chamber constantly communicating through throttle hole in barrier between steps of two-step branch pipe with atmosphere and periodically with air source of increased pressure through windows in smaller step of two-step branch pipe. Window in barrier of above-mentioned spring-loaded bushing is made in its center. EFFECT: raised functional reliability of reversing mechanism of device thanks to dynamic action of air on barrier of two-step bushing at moment of its turn across protrusions of two-step branch pipe. 3 dwg