HYDRAULIC HAMMER Russian patent published in 1998 - IPC

FIELD: construction machinery and equipment. SUBSTANCE: this is used for driving into ground piles, sheet piles, pipes, and other construction articles. Hydraulic hammer has body, striking weight, hydraulic cylinder for moving striking weight, hydraulic pump with delivery line and return line, two double-position valves which are intended for connecting piston space of hydraulic cylinder with hydraulic delivery line or return line. Each valve is made in the form of cylinder which is located and sealed inside valve body over outer diameter which is close in size to diameter of valve contact surface. Space at side of front end of valve is connected with space at side of rear end of valve which is counterpositioned relative to seat. EFFECT: higher efficiency. 2 cl, 2 dwg