PNEUMATIC PERCUSSION ACTION TOOL Russian patent published in 2006 - IPC B25D9/04 

FIELD: building industry.

SUBSTANCE: pneumatic percussion tool for trench free mounting of new and changing worn underground pipelines includes: hollow housing; striker having through stepped cavity and radial ducts in walls; stepped branch pipe with lengthwise duct mounted by its large step inside striker and by its small step secured to housing; air exhaust unit; chambers for working stroke and idle stroke of striker. Lengthwise duct of branch pipe is closed in zone of its large step. Idle stroke chamber of striker is formed between walls of striker and outer surface of branch pipe. Working stroke chamber of striker is formed by mutually communicating additional ducts of said two chambers. Inside housing between its walls, front end of striker and outer surface of tube there is chamber that is always communicated with atmosphere through additional windows of tube walls.

EFFECT: improved design providing increased striking power, enhanced operational reliability of tool.

2 dwg