Abstract: The present invention relates to a drill rod (2) for a fluid-operated apparatus, particularly a percussion drill tool (1). The drill rod (2) comprises a first connection interface (100) at a first end (101) and a second connection interface (102) at a second end (103). The first connection interface (100) is for connection of the drill rod (2) to a second connection interface (102) of a like drill rod (3) or to the apparatus (1). The second connection interface (102) is for connection of the drill rod (2) to a first connection interface of a like drill rod (3) or to a fluid transfer device. The drill rod also comprises a plurality of discrete fluid flow channels (4, 6, 8) through the drill rod, a first member (23) moveably mounted in the first connection interface (100) and a second member (22) moveably mounted in the second connection interface.

Abstract: A down-the-hole drill hammer is provided that includes a housing, a drill bit proximate a distal end of the housing, and a roller bearing assembly. The roller bearing assembly circumscribes the drill bit. The roller bearing assembly includes a race and a plurality of rollers. The plurality of rollers are operatively engaged with the race.

Abstract: A percussive drill for extension drilling includes a drill bit, a tube having a male screw thread attached to a female screw thread of the drill bit, and a rod having a male screw thread attached to a female screw thread of the tube. Central passages of the rod and tube are aligned with one another to conduct flushing fluid to the drill bit. The drill bit drills a hole whose diameter is from 60-170 mm and at least twice the outer diameter of the rod. A total area of a cross-sectional surface of the tube is within 100-125% of a total area of a cross sectional surface of the rod.

Abstract: A unitary valve assembly for a fluid-activated, percussive paving breaker includes a valve chest having an outer sidewall forming an internal valve chamber, a sidewall within the internal chamber forming a valve bore, a reciprocal valve within the valve bore and a bottom plate permanently fastened to the outer sidewall. The inner sidewall forms a first annular, upstanding sealing seat for the valve, and the bottom plate forms a second annular, upstanding sealing seat for the valve. Passageways through the valve assembly are positioned so as to connect with high and low pressure chambers of a paving breaker, when the valve assembly is inserted into the paving breaker. For weight reduction, the valve assembly is made of acetal resin.

Abstract: A system for lubricating and reciprocating a piston in a fluid-activated, percussive paving breaker includes a unitary valve assembly positioned within a bore of a rear portion of a tool housing, the valve assembly having an oil reservoir for lubricating the piston. The valve assembly is retained in place by a combination of a throttle lever and a backhead plate bolted to the rear tool housing.

Abstract: A system for lubricating and reciprocating a piston in a fluid-activated, percussive paving breaker includes a unitary valve assembly positioned within a bore of a rear portion of a tool housing, the valve assembly having an oil reservoir for lubricating the piston. The valve assembly is retained in place by a combination of a throttle lever and a backhead plate bolted to the rear tool housing.

Abstract: A system for lubricating and reciprocating a piston in a fluid-activated, percussive paving breaker includes a unitary valve assembly positioned within a bore of a rear portion of a tool housing, the valve assembly having an oil reservoir for lubricating the piston. The valve assembly is retained in place by a combination of a throttle lever and a backhead plate bolted to the rear tool housing.

Abstract: A throttle lever system for operating a flushing system on a percussive, fluid-activated apparatus includes a fluid inlet port, passageways in the apparatus for exhaust fluid, a seal device for opening and closing the passageways, and a throttle lever system for operating the seal device, the throttle lever system including a one-piece throttle lever elastically and pivotally mounted on a pivot pin on the device to cantilever out over the seal device, whereby the lever elastically moves up and down into and out of contact with the seal device, in response to operator hand pressure.

Abstract: A debris flushing system for a percussive, fluid-activated apparatus includes a first and second separate and independent flushing system in the apparatus, each flushing system having a separate combination of passageways in the apparatus for fluid communication between an inlet port and a front piston exhaust chamber. Each flushing system has a separate seal and throttle combination for opening and closing its own passageways. A third, independent flushing system for flushing water can be added to the apparatus.

Abstract: An air hammer powered debris chisel headed tool having a water stream blaster outlet directing a high speed water stream forwardly closely adjacent and above the chisel head when valve controlled for use. Air misting outlets are also provided at the forward end of the tool to produce a dust debris supressing mist as the tool is being used in material removal such as asbestos dust abatement as asbestos is being removed in structures. A trigger control at the butt handle end of the tool controls on-off activation of the tool air hammer, and a lever on the butt handle has control settings from off to misting to combination misting and high speed water stream to high speed water stream alone.

Abstract: A percussion drilling tool assembly is provided which operates under fluid pressure to reciprocating a hammer, the hammer is disposed in a barrel assembly and operates to strike an anvil bit shank to cause the bit to thereby penetrate a rock substrate material of central fluid passage through the drill stem of the assembly and through the reciprocating hammer allows a flushing fluid to be used with the drilling assembly to flush cuttings from the hole up and around the drill stem simultaneously with and separate from the fluid operating system for reciprocating the hammer.

Abstract: A percussion drilling tool assembly is provided which operates under fluid pressure to reciproce a hammer, the hammer is disposed in a barrel assembly and operates to strike an anvil bit shank to cause the bit to thereby penetrate a rock substrate material. A central fluid passage through the drill stem of the assembly and through the reciprocating hammer allows a flushing fluid to be used with the drilling assembly to flush cuttings from the hole up and around the drill stem simultaneously with and separate from the fluid operating system for reciprocating the hammer. The drill stem includes intake and exhaust passages for pressured working fluid as well as a mud passage for the flushing fluid or mud, the drill stem is made up in sections connected to form a string which extends the length of the hole and provide the pressured working fluid and mud to the pneumatic tool connected at the end of the drill stem.