Hydraulic demolishing rock drill
AssigneeGiovanni Donadio
InventorMario Musso
Life of this patent
Estimating the term…
Abstract
Hydraulic breaking down or demolishing rock drill in which there is a stroke only pressing the drill against the surface to be broken down or drilled. The result is a reduced hard work of the operator and a reduced wear of the drill parts. This drill has an axial chamber body made of different cylindrical sectors, in which is sliding a rammer having two cylindrical joint elements of different diameter: the upper having a groove while the lower has an annular band-like piston ring. An intermediate sector of the axial chamber is equipped with a distributing valve for the oil, controlling the various working phases. The drill body is equipped with various oil pipes joining the oil tank with the sectors of the axial chamber, or such sectors altogether. The drill is also equipped with a device regulating the impact frequency.
Claims17
Hydraulic rock drill comprising:
- a body having an axially extending chamber formed therein, said chamber having a plurality of axially aligned sectors including a lowermost sector, a chamber sector, an intermediate sector, and an upper sector, the diameter of said intermediate sector being greater than the diameter of said upper sector;
- a bit having a core portion disposed in said lowermost sector and an operative portion protruding from the body;
- a rammer disposed for reciprocating movement in said chamber and having a lower surface engageable with the core portion of the bit, a lower element carrying a piston ring, and an upper element having a groove spaced from an end surface thereof;
- said piston ring being enegagable with side walls of said chamber sector to divide said chamber into an upper piston chamber and a lower piston chamber;
- valve means disposed in said intermediate sector for controlling supply of hydraulic fluid to said sectors of said chamber;
- an inlet duct formed in said body connectable to a source of pressurized hydraulic fluid, said inlet duct communicating with a lower portion of said intermediate sector and a lower portion of said upper sector;
- an outlet duct communicating with an intermediate portion of said intermediate sector for returning fluid to the fluid source;
- a first duct for communicating a lower portion of said intermediate sector with said lower piston chamber;
- a second duct for communicating an intermediate portion of said intermediate sector with said upper position chamber;
- a third duct for communicating an upper portion of said upper sector with an upper portion of said intermediate sector;
- a fourth duct having one end communicating with said upper sector and a second end communicating with a portion of said intermediate sector spaced from the upper end of said intermediate sector, said valve means having an upper portion in sliding engagement with side walls of said intermediate sector disposed between said second end of said fourth duct and said upper end of said intermediate sector;
- said valve means having first, second, and third operating modes, said valve means in the first mode directing fluid flow in such manner that the rammer remains in a lowermost position thereof, said valve means in the second mode directing fluid in such manner that the rammer is moved towards a raised position thereof, and said valve means in the third mode directing fluid flow in such manner that the rammer moves from the raised position thereof towards the lowermost position thereof.
Dependencies are inferred from the claim text.