Abstract: A pressurized fluid flow system for percussive mechanisms comprises a cylinder coaxially disposed in between an outer casing and a piston which reciprocates due to the changes in pressure of the pressurized fluid contained inside a front chamber and rear chamber located at opposites sides of the piston. The discharge of fluid from these chambers being conducted through a set of discharge channels and the supply of fluid to the front chamber being conducted through a set of supply channels and a front set of recesses. The supply of fluid to the rear chamber being conducted through a piloted valve.

Abstract: A pressure reversing valve for a fluid-actuated percussive drilling tool has a front thrust surface in communication with a rear chamber and a rear thrust surface in communication with a pressurized volume isolated from the flow coming from the source of pressurized fluid. The pressurized volume is in communication with a front chamber and allows the valve to take advantage of the imbalanced profile of the pressures inside the front and rear chambers that naturally occurs for enabling an asymmetric feeding process of the rear chamber that is also less sensitive to the bottom hole pressure.

Abstract: A pressurized fluid flow system for a down the hole drill hammer has main and auxiliary chambers that exert work on the piston. The auxiliary chambers are formed around respective waists on the piston and externally delimited by respective cylinders which are arranged longitudinally in series. A set of supply chambers filled with the pressurized fluid are defined by annular recesses in the external surface of the piston for supplying said fluid to the chambers. Supply channels and discharge channels are formed in between the outer casing and the cylinders for respectively supply pressurized fluid through exit ports in the cylinders to the supply chambers and emptying the chambers through discharge ports in the cylinders. The supply and discharge of the chambers is controlled in a cooperative way by the piston and the cylinders. A normal circulation drill hammers is provided having this system.

Abstract: A pressurized fluid flow system for a down the hole drill hammer has main and auxiliary chambers that exert work on the piston. The auxiliary chambers are formed around respective waists on the piston and externally delimited by respective cylinders which are arranged longitudinally in series. A set of supply chambers filled with the pressurized fluid are defined by annular recesses in the external surface of the piston for supplying said fluid to the chambers. Supply channels and discharge channels are formed in between the outer casing and the cylinders for respectively supply pressurized fluid through exit ports in the cylinders to the supply chambers and emptying the chambers through discharge ports in the cylinders. The supply and discharge of the chambers is controlled in a cooperative way by the piston and the cylinders. A normal circulation drill hammers is provided having this system.

Abstract: A pressurized fluid flow system for a normal circulation down-the-hole hammer comprises a cylinder coaxially disposed in between an outer casing and a piston which reciprocates due to changes in pressure of pressurized fluid contained inside a front chamber and rear chamber located at opposites sides of the piston, the supply/discharge of fluid to/from these chambers being conducted through sets of supply and discharge channels defined by recesses on the outer surface of the cylinder and arranged in a parallel fashion, the fluid flow into and out of the front and rear chambers being controlled solely by the relative overlap of the piston and the cylinder and channeling of the fluid flow below the inner surface of the cylinder and above the outer surface of the piston. A hammer having this system comprises a drill bit with one or more flushing passages.

Abstract: A pressurized fluid flow system for a down the hole drill hammer has a plurality of chambers that exert work, namely one or more auxiliary drive and lifting chambers besides two main chambers located at opposite ends of the piston, the auxiliary chambers each formed around respective waists on the piston and externally delimited by respective cylinders which are arranged longitudinally in series. Two or more internal chambers filled with the pressurized fluid are defined by recesses in the inner surfaces of the piston for supplying said fluid to the work chambers, controlled in a cooperative way by the piston and a control tube coaxially arranged within a central bore of the piston. One or more discharge chambers are formed in between the outer casing and the cylinders for emptying the work chambers through discharge ports in the cylinders. Reverse and normal circulation drill hammers are provided having this system.

Abstract: A pressurized fluid flow system for a reverse circulation down-the-hole hammer includes a cylinder and a cylindrical control tube that are respectively coaxially disposed in between the outer casing and the piston of the hammer and in between the piston and the sample tube. Two chambers help to respectively supply and discharge pressurized fluid into and out of the front and rear chambers that exert work on the piston: an internal chamber, defined by a central recess in the inner surfaces of the piston and permanently connected to the source of pressurized fluid, and a discharge chamber, defined by one or more recesses in the inner surface of the outer casing and permanently communicated with the bottom of the hole. A hammer provided with this system has one or more end discharge ports connected to respective longitudinal discharge channels formed on the outer surface of the outer casing.

Abstract: A pressurized fluid flow system for a down the hole drill hammer has a plurality of chambers that exert work, namely one or more auxiliary drive and lifting chambers besides two main chambers located at opposite ends of the piston, the auxiliary chambers each formed around respective waists on the piston and externally delimited by respective cylinders which are arranged longitudinally in series. Two or more internal chambers filled with the pressurized fluid are defined by recesses in the inner surfaces of the piston for supplying said fluid to the work chambers, controlled in a cooperative way by the piston and a control tube coaxially arranged within a central bore of the piston. One or more discharge chambers are formed in between the outer casing and the cylinders for emptying the work chambers through discharge ports in the cylinders. Reverse and normal circulation drill hammers are provided having this system.

Abstract: A pressurized fluid flow system for a normal circulation down-the-hole hammer comprises a cylinder coaxially disposed in between an outer casing and a piston which reciprocates due to changes in pressure of pressurized fluid contained inside a front chamber and rear chamber located at opposites sides of the piston, supply/discharge of fluid to/from these chambers being conducted through a supply chamber and a discharge chamber defined by recesses on the inner surface of the casing and separated by a dividing wall, the front/rear chambers' in/out fluid flow being controlled solely by the overlap of the piston and the cylinder. A hammer having this system comprises a drill bit with one or more flushing passages which extend from channels cooperatively formed between splines on the inner surface of the driver sub and on the outer surface of the drill bit shank up to the front face of the drill bit.

Abstract: A pressurized fluid flow system for a reverse circulation down-the-hole hammer includes a cylinder and a cylindrical control tube that are respectively coaxially disposed in between the outer casing and the piston of the hammer and in between the piston and the sample tube. Two chambers help to respectively supply and discharge pressurized fluid into and out of the front and rear chambers that exert work on the piston: an internal chamber, defined by a central recess in the inner surfaces of the piston and permanently connected to the source of pressurized fluid, and a discharge chamber, defined by one or more recesses in the inner surface of the outer casing and permanently communicated with the bottom of the hole. A hammer provided with this system has one or more end discharge ports connected to respective longitudinal discharge channels formed on the outer surface of the outer casing.

Abstract: A pressurized fluid flow system for a normal circulation down-the-hole hammer comprises a cylinder coaxially disposed in between an outer casing and a piston that reciprocates due to changes in pressure of the pressurized fluid contained inside of a front chamber and a rear chamber located at opposites sides of the piston, wherein the flow into and out of these chambers is controlled solely by the overlap or relative position of the piston and the cylinder as a supply chamber and a discharge chamber defined by recesses on the inner surface of the outer casing and separated by a dividing wall control the flow of pressurized fluid in and out of the front and rear chambers the.

Abstract: A pressurized fluid flow system for a reverse circulation down-the-hole hammer having a cylinder coaxially disposed in between an outer casing and the piston. This piston reciprocates due to changes in pressure of the pressurized fluid contained inside of a front chamber and a rear chamber at opposite sides of the piston, where the flow into and out of these chambers is controlled solely by the overlap or relative position of the piston and the cylinder as a supply chamber and a discharge chamber, which are defined by recesses on the inner surface of the outer casing and separated by a dividing wall, respectively, supply to and discharge from the front and rear chambers, the pressurized fluid. An internal chamber may also be provided in between the piston and a sampling tube coaxial with the outer casing for a more efficient filling of the chambers.

Abstract: A pressurized fluid flow system for a reverse circulation down-the-hole hammer comprising a cylinder (40) coaxially disposed in between the outer casing (1) and the piston (60); and two chambers (2, 3) defined by respective recesses on the inner surface of the outer casing (1) and separated by a dividing wall (5). During the operation of the hammer, the first chamber (2) is permanently connected to the source of pressurized fluid for supplying said fluid to a front chamber (240) and to a rear chamber (230) formed inside the hammer and located at opposite ends of the piston (60) for enabling it to reciprocate due to the changes in pressure of the pressurized fluid contained therein; and the second chamber (3) is permanently communicated with the bottom of the hole for discharging the pressurized fluid from said chambers (240, 230); wherein the flow into and out of said chambers (240, 230) is controlled solely by the overlap or relative position of the piston (60) and the cylinder (40).