Abstract: A multi-fluid drilling system 10 drilling is disclosed for drilling a hole or well 11. The system 10 is coupled to a dual wall drill string 12. The drill string 12 is configured to enable separate flow of a first fluid 14 and a second fluid 16. The system 10 has a hammer 22 and a downhole motor 24. Both the hammer 22 and the motor 24 are supported by and are coupled to the drill string 12. The motor 24 is uphole of the hammer 22. The hammer 22 is arranged so that when supported by the drill string 12 the first fluid 14 when flowing through the drill string 12 is able to flow to and power the hammer 22. As the motor 24 is disposed between the hammer 22 and the drill string 12 the first fluid 14 is also able to flow through the motor 24. To this end the motor 24 has a channel 25 to enable the first fluid to flow from the drill sting 12 to the hammer 22. The channel 25 acts as a part of a flow path or conduit for the first fluid 14.

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: The present invention relates to a percussion rock drilling machine comprising a front head (1), in which front head (1) are arranged a flush housing (26) and a flush connector (25) for flushing medium. According to the invention, a sheath (31) of rust-resistant material is arranged at the front head (1) around the flush housing (26), such that flushing medium can enter the flush housing (26) through the flush connector (25), without coming into contact with the front head (1).

Abstract: The present invention concerns a sealing system for a tool holder of a fluid-assisted axial machining or milling machine, including:—at least first and second seals contributing to define a space for the flow of fluid to at least one inner channel of the tool, one of the seals being applied to the tool or an optional adapter carrying the tool and the other seal a) being applied to the tool or to the adapter carrying the tool or b) being applied to a surface spaced apart from the tool and rotating with same, with 0.3?Do/Djmax for Do in the interval [1; 3] in mm and 0.5?Do/Djmax for Do in the interval [3; 20] in mm, where Do is the diameter of the tool facing this other seal and Djmax is the internal diameter of this seal.

Abstract: A method and means of minimizing the effect of elastic valve recoil in impact applications, such as percussive drilling, where sliding spool valves used inside the percussive device are subject to poor positioning control due to elastic recoil effects experienced when the valve impacts a stroke limiting surface. The improved valve design reduces the reflected velocity of the valve by using either an energy damping material, or a valve assembly with internal damping built-in, to dissipate the compression stress wave produced during impact.

Abstract: An impulsive unit for a jack hammer or rock drill is adapted to be powered by water, and comprises a piston slidable within a cylinder, and carrying a striker portion thereon. At least a portion of the piston and/or cylinder is coated with ceramic. The ceramic is most suitably an aluminum oxide-titanium dioxide composite, which enables the clearance between the internal diameter of the cylinder and the external diameter of the piston to be reduced to between 8 and 10 micro-meters.

Abstract: A pneumatic device control apparatus and method comprising a ported valve slidably fitted over a feed tube of the pneumatic device, and using a compliant biasing device to constrain motion of the valve to provide asymmetric timing for extended pressurization of a power chamber and reduced pressurization of a return chamber of the pneumatic device. The pneumatic device can be a pneumatic hammer drill.

Abstract: A powered hammer includes a housing, a tool holder coupled to the housing and configured to hold a tool, a motor within the housing, a cylinder disposed within the housing, and a piston slideably mounted within the cylinder. A drive mechanism converts rotary output of the motor into a reciprocating motion of the piston. The drive mechanism includes a crank shaft rotationally driven by the motor, a drive pin eccentrically mounted on the crank shaft, and a con rod with a first end connected to the drive pin and a second end connected to the piston. A ram is slideably mounted forward of the piston that is reciprocatingly driven by the piston. A beat piece is slideably mounted forward of the ram. The beat piece is repetitively struck by the reciprocating ram, which in turn repetitively strikes an end of the tool when held in the tool holder to transfer the momentum of the ram to the tool. Lubrication fluid covers at least part of the drive mechanism.

Abstract: Apparatus for driving an open-ended conductor pipe into the ground. The apparatus includes, in combination, an open-ended conductor pipe capable of being driven into the ground, a drill string, a device for pumping fluid through the drill string, an arrangement for supporting the conductor pipe on the drill string, and a reciprocable impact driver supportable by the drill string within the conductor pipe. The apparatus further includes a device for reciprocating the reciprocable impact driver using fluid pumped through the drill string, an anvil capable of transferring the percussive force of the reciprocable impact driver to the conductor pipe, and jets for jetting fluid into the lower portion of the conductor pipe.

Abstract: A powered hammer includes a housing, a tool holder coupled to the housing and configured to hold a tool, a motor within the housing, a cylinder disposed within the housing, and a piston slideably mounted within the cylinder. A drive mechanism converts rotary output of the motor into a reciprocating motion of the piston. The drive mechanism includes a crank shaft rotationally driven by the motor, a drive pin eccentrically mounted on the crank shaft, and a con rod with a first end connected to the drive pin and a second end connected to the piston. A ram is slideably mounted forward of the piston that is reciprocatingly driven by the piston. A beat piece is slideably mounted forward of the ram. The beat piece is repetitively struck by the reciprocating ram, which in turn repetitively strikes an end of the tool when held in the tool holder to transfer the momentum of the ram to the tool. Lubrication fluid covers at least part of the drive mechanism.

Abstract: A powered hammer includes a housing, a tool holder coupled to the housing and configured to hold a tool, a motor within the housing, a cylinder disposed within the housing, and a piston slideably mounted within the cylinder. A drive mechanism converts rotary output of the motor into a reciprocating motion of the piston. The drive mechanism includes a crank shaft rotationally driven by the motor, a drive pin eccentrically mounted on the crank shaft, and a con rod with a first end connected to the drive pin and a second end connected to the piston. A ram is slideably mounted forward of the piston that is reciprocatingly driven by the piston. A beat piece is slideably mounted forward of the ram. The beat piece is repetitively struck by the reciprocating ram, which in turn repetitively strikes an end of the tool when held in the tool holder to transfer the momentum of the ram to the tool. Lubrication fluid covers at least part of the drive mechanism.

Abstract: A vibration reduction and lubricating mechanism for a powered hammer includes a power driven piston in a cylinder that reciprocatingly drives a ram, which repetitively strikes a beat piece, which repetitively strikes a tool received in a tool holder. The vibration reduction and lubricating mechanism includes a first chamber defined in a housing of the powered hammer. A second chamber is defined within an end portion of the cylinder facing the beat piece, forward of the ram. A passageway is in communication with the first and second chambers. A counter mass is mounted for oscillating movement within the first chamber. When the hammer is operated, the counter mass is caused to oscillate to counteract vibration in the housing and to cause lubrication fluid to move between the first and second chambers.

Abstract: A hydraulic rock drill comprises a housing having a piston and valve bore formed therein, a rotation motor, and a fluid connection and fluid reservoir interposed between the housing and the rotation motor. Fluid connections to the hydraulic rock drill comprise a single inlet fluid connection to the housing and a single exhaust fluid connection from the rotation motor. The working shoulder areas of the piston are proportioned so that the exhaust stroke of the piston will pressurize the fluid in the reservoir, providing a fluid inlet source for the rotation motor. When the rotation torque demand increases, pressure in the fluid reservoir and pressure in the fluid inlet connection will rise accordingly, thus providing higher rotation torque while maintaining impact power. When fluid inlet pressure reaches a predetermined limit, rotation and impact will lessen or cease altogether.

Abstract: Provided is a downhole percussion drill, which is installed at an end portion of a drillstring and performs drilling by giving impact blows to a drill bit at the bottomhole, which includes a hydraulic hammering mechanism 7 which uses oil having high lubricating ability as a driving medium, a hydraulic pump 8 which pressurizes the oil, and a downhole motor 9 which drives the hydraulic pump 8.

Abstract: A improved "mud motor" for use in oil and gas well drilling includes a reciprocating valve and piston arrangement that generates power using drilling fluid media (e.g., drilling mud) pumped through an inlet port to form a differential across a piston seat. The differential pressure causes the valve and piston assembly to move down in an elongated body. Rollers then force telescoping, reciprocating fingers to rotate while absorbing the reciprocating up and down action of the valve and piston assembly. This clockwise rotation causes a transmission that includes a clutch shaft and sprags to engage a clutch housing causing the drill bit to turn. Thrust bearings allow weight to be applied to the tool to optimize drilling action. The apparatus can be used in well drilling or in the removal of obstructions such as bridge plugs, metal and rubber from the well bore.

Abstract: An in-hole hammer for boring in ground has an elongated hollow housing carrying an internal striking piston in a piston chamber. An exchangeable boring head is threadably connected to the forward end of the housing and the striking piston impacts against the forward wall of the housing defining the piston chamber to transmit forward driving impact energy to the boring head. A boring rod which urges the hammer forwardly and rotates it about the longitudinal axis is connected to the rear end of the housing through a connecting piece non-rotatably fixed, but slidable relative, to the housing so that the axially directed impact energy produced by the striking piston is not transmitted to the boring rod.

Abstract: A pneumatic downhole impact drill has a backhead for mounting an inlet check valve and a mounting hub for mounting a fluid delivery tube. A split ring has an interior circumferential groove forming upper and lower shoulders and comprises two substantially identical semi-circular ring segments. The ring segments are positioned around flanges on the backhead and the mounting hub such that the upper shoulder of the split ring slidably engages the upper surface of the backhead flange and the lower shoulder slidably engages the lower surface of the mounting hub flange to mount the backhead to the mounting hub. A first gap is formed between the outside surface of the split ring and the inside surface of the casing. A second gap is formed between the inside surface of the groove and the outside surfaces of the mounting hub and backhead flanges. Taken together, the gaps allow lateral relative movement between the mounting hub and backhead flanges.

Abstract: A water driven hammer device has a machine housing and a hammer piston movable to-and-fro in the machine housing. The hammer piston is guided in the machine housing in two guides separated from each other. The guides are formed from two parts each having different inner diameters, and the parts with the largest inner diameters on the guide are turned towards each other. A room between the guides is pressurized and chambers on the other side of the guides are kept at a lower pressure, resulting in fluid flow through the guides for centering the hammer piston in the machine housing to avoid seizure of the hammer piston.

Abstract: An in-hole rock drilling machine has a hydraulic impact motor within a housing. The hydraulic impact motor has a spool valve contained within a valve housing. The spool valve has two operating positions to alternately pressurize and depressurize a drive chamber to reciprocate a hammer. The spool valve has a continuously pressurized third control surface that biases the spool valve towards a second operating position, a first control surface that acts opposite the third control surface to move the spool valve to a first operating position, and a second control surface that acts with the third control surface to return the spool valve to the second operating position. The valve housing guides the rear portion of the hammer, and a guide bushing guides the front portion of the hammer. The guide bushing, valve housing, and a distance sleeve are clamped against a shoulder of the housing.

Abstract: A hydraulic reciprocating percussion tool, particularly adapted for drilling applications, comprises an elongated cylinder, opposed fronthead and backhead members and a central bore in the cylinder for supporting a reciprocating piston hammer. The piston hammer has reduced diameter end portions which have respective tubular sleeve valves disposed in sleeved relationship thereon and engageable with valve retainer members on the reduced diameter portions for effecting movement of the valves with the piston hammer. The head members include tubular sleevelike stem portions which cooperate with the respective valves to valve pressure fluid to and from opposed chambers in the cylinder to effect repeated impact blow delivering strokes to a shank member disposed in a chuck connected to the fronthead.

Abstract: According to the invention, a drill hammer (10) generally comprises an outer tube (55), a control casing jacket (60) inclusive of check valve (59) and a central tube (80) having radial passages (81, 83). A ram (75) is guided on central tube (80), onto the lower and preferably recessed end (84) of which the head of a drill steel (90) may slide. A cylinder liner (70) that may be provided with outer ribs (101) also guides ram (75) and is peripherally welded to outer tube (55) along a welding zone S of axial length l. Above control casing jacket (60), there is an adapter (40) comprising downstream channels (43) and carrying a blowing collar (50) provided with upwardly directed nozzles (53). A drive-transmitting sleeve (15) below a screw head (11) is joined to the adapter (40) either directly or via a shift unit (30) that guides a shaft (20) whose lower end (23) may form a slide valve relative to an upper adapter portion (41). From there, passages (42, 47) lead to a control casing jacket (62) having channels (63).

Abstract: A fluid distributor for a debris flushing system in a fluid-activated jackhammer includes a bore through a reciprocal piston, for fluid flow into an exhaust chamber, a fluid distributor removably mounted in the piston bore, the fluid distributor operating by forming passageways through the bore and blocking flow in other portions of the bore. The distributor can have a tapered body that can be severed along its length by the operator to provide a plurality of preselected, fixed flow rates.

Abstract: Down-the-hole drill comprising a housing (1), a hammer piston (6) movable to-and-fro in the housing and intended for impacting a drill bit (5). A back piece (3) provided with an extension (12) with a valve part (17) cooperates with a part (8) of a central channel in the hammer piston. This part of the central channel comprises a zone (16) with larger diameter than adjacent parts at an intermediate part of this part. This results in that pressure medium can pass the valve part when it is situated at the zone and that the valve part and the hammer piston sealingly cooperate when the valve part is on either side of the zone.

Abstract: A pneumatic percussion hammer for attachment to a drill tube is coaxially constructed about an outflow tube which is mounted therein for axial removal and replacement when worn. A cylindrical piston moves axially between a top sub wherein a drill stem is screwed, and an anvil of a bit at the bottom. A casing and the piston are configured to valve the flow of pressurized air therethrough for reciprocating motion of the piston and an outflow that carries debris through the outflow tube and drill stem.

Abstract: A downhole percussion drill or hammer (100) is disclosed having an outer casing (2) in which a reciprocating piston (26) which periodically impacts a drilling bit (16) disposed at a bottom end of the casing. A top chuck (1), attached to the top end of the casing, conducts pressurized air to the interior of the casing. A flow tube (5) includes a supply passage (27) and an exhaust passage (10). No cylinder sleeve exists between the inner diameter of the casing (2) and the outer diameter of the piston (26). Rather, the flow tube (5), piston (26) and interior structure of the casing cooperate to direct pressurized air alternately to the top and bottom ends of the piston while alternately opening and closing the exhaust passage. Accordingly, for a predetermined outer casing diameter, a relatively thicker casing wall and relatively larger top piston surface results in higher relative performance than prior hammers having a cylinder sleeve.

Abstract: The hydraulic jackhammer is provided with a rotor turbine which is driven by a liquid stream in order to activate the tup for driving against a jumper rod. After passing by the turbine rotor, the liquid stream is mixed with air and passed through a nozzle into a guide channel under pressure in order to cool the casing. Some of the liquid-air mixture is passed through the hollow jumper rod for spraying onto a jumper bit and sprayed onto the rock being drilled.

Abstract: A valveless-type down-the-hole hammer drill which has an inner tube extending from the upper end of the hammer body into a central opening in a cutter bit reciprocably mounted in a chuck on the opposite end of the hammer body. High pressure fluid is supplied to the interior of the inner tube and a piston surrounding the inner tube has internal surfaces controlling connection of a port to chambers above and below the piston. The external surface of the piston controls connection of these chambers to an exhaust port. A valve sleeve on the chuck coacts with the piston in this respect.

Abstract: The invention is concerned with pneumatic percussion drilling equipment with advantageous manufacturing simplicity and effective piston area to casing size consisting essentially of an elongate hollow casing housing a piston assembly and having a backhead at one end with a compressed fluid inlet, a bit assembly with a compressed fluid exhaust at the other end, and the backhead including a seal for a backhead end of the piston reciprocatable within the casing, the piston having axial bores extending inwardly from each end, inclined passages extending away from the inner ends of the axial bores to open through the wall of the piston at positions axially displaced from each other and towards opposite ends of the piston from their respective axial bores, and the casing walls having axially spaced apart recesses, the backhead seal, casing recesses and opening through the wall of the piston being such as to allow fluid under pressure introduced axially into the casing through the backhead, to reciprocate and to mai

Abstract: A percussion drill rod assembly comprising an elongated inner percussion blow transmitting rod of substantially constant diameter supported in a tubular torque transmitting coupling member by spaced apart sets of resilient isolator members secured to the tubular coupling member. The drill rod assembly is connected to a shank assembly at the drill motor and an adaptor assembly at the bit end, each of which include inner percussion blow transmitting members and outer torque transmitting members. Integral drill rod assemblies having inner percussion rods and outer torque transmitting tubular coupling members are adapted for use with feed leg and sinker drills, for example.

Abstract: A drill string for top hammer drilling includes a drill bit, a set of central rod members for transferring impact energy to the drill bit, and a set of tubular members surrounding the rod members for transferring rotation to the drill bit. The rod members define a first internal channel for conducting flushing medium. The drill bit defines a second internal channel which extends rearwardly and penetrates a rear end of the drill bit to communicate with the first channel. The drill bit further includes a transverse channel disposed in an intermediate section of the drill bit and which is connected to the second channel. The transverse channel penetrates an envelope surface of the drill bit for conducting flushing medium out of the drill bit and into an enlarged space defined between the drill bit and the tubular member.

Abstract: A percussion drill comprises a drill bit and a reciprocable hammer piston for imparting blows to the bit. Pressurized air is supplied to the piston for reciprocating the piston. Some of the air is by-passed to an exhaust passage and is exhausted ahead of the bit for removing cuttings. An indexable choke valve is disposed in the exhaust passage for regulating the amount of air which is exhausted. The choke valve comprises a portion of a valve carrier which carries a check valve at its rear end. The valve carrier is rotatable to produce an indexing of the choke valve. The valve carrier is insertable in a front-to-rear direction into a central opening of a rear sub and is secured to the rear sub by a pin which also holds the choke valve in selected positions of adjustment.

Abstract: A valveless-type down-the-hole hammer drill which has an inner tube extending from the upper end of the hammer body into a central opening in a cutter bit reciprocably mounted in a chuck on the opposite end of the hammer body. High pressure fluid is supplied to the interior of the inner tube and a piston surrounding the inner tube has internal surfaces controlling connection of a port to chambers above and below the piston. The external surface of the piston controls connection of these chambers to an exhaust port. A valve sleeve on the chuck coacts with the piston in this respect.

Abstract: A downhole reverse circulation hammer is provided comprising a tubular housing and a top sub and drill bit supported mounted on either end of the housing. A central axis tube extends through the housing, top sub and drill bit support and a piston is slidably positioned in the tube. The hammer has a network of fluid passageways and spaces which enable the piston to reciprocate against an anvil in response to the entry and exit of a fluid into the spaces via the passageways.

Abstract: In a scavenger is supplied through a scavenging pipe (26) to the internal pipe string (11), the scavenging pipe (25) extending through a bore (27) of the hammer piston (17) of the hammer drill. Due to a rotary drive (14), the drilling strings (10,11) are rotated which are connected to the shank (13) extending into the rotary drive (14). The scavenger is conducted through the scavenging pipe (26) into the shank (23) and from there into the internal pipe string (11). The external diameter of the scavenging pipe (26) is inferior to the inner diameter of the bore (27) of the hammer piston (17), and of the scavenging bore (23). Sealing between the scavenging pipe (26) and the scavenging bore (23) is effected by a thick head piece (33) at the end of the scavenging pipe. Said head piece (33) contains a seal rubbing along the cylindrical scavenging bore wall if the hammer piston (17) strikes on the shank (13).

Abstract: An improved fluid actuated rock drill hammer as shown having a cylinder housing, a reciprocal piston, and a centralized air distributing control tube axially extending through a central bore in the piston for controlling the operation of the piston. The control tube is mounted for assured concentricity of the tube within the piston bore and comprises a unitary mounting portion and tubular portion. The mounting portion includes a piloting section for concentric fit within the cylinder as received on a shoulder therein and the tubular portion extends concentric and perpendicular to the piloted section.

Abstract: A drill bit for use in a drill string comprising a set of a plurality of central rod members and a set of a plurality of tubular members surrounding said rod members. The drill bit is provided with a longitudinally extending flushing channel which communicates with an annular space between the rod members and the tubular members via a transverse passage. The flushing channel comprises at least two end passages terminating in the bit front. The cross section area of each of the end passages is smaller than the overall cross section area of the portion of the flushing channel located between the end passages and the transverse passage.

Abstract: A down hole hammer comprising a substantially cylindrical casing having a top sub at one end and a drill bit support at the other; a central passageway extending through the top sub, casing and drill bit support; a central tube coaxial with the casing and extending from the bottom of the top sub to the top of the bit support thereby defining an annular space between its outer surface and the internal face of the casing, its inner bore forming part of the central passageway; an annular piston reciprocatively accommodated within the annular space for movement between an impact position at which said piston abuts the drill bit support, and a raised position at which said piston is spaced from the drill bit support; fluid porting being provieded to said annular space to effect the reciprocation of the piston between the raised and impact positions, the exhaust from the annular space during reciprocation of the piston being exhausted into the central passageway; a fluid by-pass extending between the top sub and th

Abstract: A valveless pneumatic hammer comprising a backhead assembly at one end of a hollow casing and a bit assembly at the other end of the casing, a rod extending into the casing and having a passage out to atmosphere at the other end of the assembly, a chamber divider in the backhead end of the casing having a control rod projecting into the casing, a piston having a large bore in one end and a smaller bore end and the larger bore end being adapted to cooperate with the chamber divider end for the sealing of the larger bore, the piston reciprocating between a first position with the smaller bore end against the bit assembly, and a second position with the piston displaced towards the backhead assembly, a first chamber with the piston in the first position, a second chamber with the piston in the second position, first and second fluid supply paths through the backhead assembly, between chamber divider walls and the casing wall, first and second fluid exhaust paths from the first and second chambers, respectively o

Abstract: In a percussive tool in which a very high pressure and preferably cavitating water jet is directed through an opening in the working surface of the tool, the jet is formed by a nozzle positioned in a cavity behind the opening and decoupled from the tool by a bearing layer of water from the jet. A supply pipe extends rearwardly of the nozzle without contacting the tool, and is supported externally of the tool, on a machine which operates the tool, by a support which allows the fluid bearing to center the nozzle within the cavity while restraining movement of the nozzle axially of the tool.

Abstract: A rock drill for drilling a plurality of arrayed continuous bores includes a plurality of rods positioned so as to be able to drill several arrayed continuous bores, a rotating member to give rotation to the rods and a single percussion member which imparts percussive force to the plurality of rods. The plurality of rods may be passed through integrally formed rod guides by connecting several cylindrical members juxtaposed in parallel. The guide rod may optionally include, at its rear end, a swivel which also acts as a rod holder.

Abstract: Pressurized water is used to operate a percussive down-the-hole drill and the spent motive fluid is used as a flushing fluid. A rear cylinder chamber (24) is constantly pressurized and a valve (28) controls the inlet from the chamber (24) to a bore (23) through the piston hammer (21). A valve (42) controls the outlet from the front cylinder chamber (26) to a flushing channel (38) in the drill bit (21). A check valve (45) controls the outlet from the bore (23) to the front cylinder chamber (26).

Abstract: A reciprocating machine comprising a cylinder with a drive chamber and a return chamber; a piston arranged to move to and fro in the cylinder with a first piston area exposed to the drive chamber and being smaller than a second piston area exposed to the return chamber; a permanently open inlet for fluid to the drive chamber; a restricted outlet for fluid from the return chamber; a bore extending through the piston from a port in its first area to its second area; a first valve with a head adapted to seat on the port and a stem guided in the end wall of the drive chamber; and means for limiting the extent of travel of the first valve with the piston so that the first valve can travel with the piston only part of the way from the drive chamber toward the return chamber.

Abstract: A fluid operated rock drill hammer includes an annular hammer body with the upper end of the hammer body adapted to be connected to a drill string and with a drill chuck mounted at the lower end of the hammer body. A drill bit extends through the drill chuck into the body. A piston is slidably mounted in the hammer body to move between the drill bit and the upper end of the hammer body for striking the portion of the drill bit that extends through the drill chuck. The force for moving the piston is provided by a fluid that is circulated through the drill string into the hammer body. A restricted exhaust port is provided for preventing back hammering of the piston by maintaining a high fluid pressure in the space between the piston and the upper end of the hammer body when the bit is off bottom.

Abstract: The device described contains a pneumatically operated hammer, a feeder controlling the flow of pneumatic fluid, an anvil which is struck repeatedly by the hammer, a drill bit attached to or integral with the lower end of the anvil, and an outer casing. The device is typically used as a down hole tool in rotary drilling operations and normally utilizes pressurized air as its pneumatic fluid. The pneumatic fluid first lifts the hammer above the anvil and second pushes the hammer downward to impact against the anvil in a striking movement. Simultaneous with striking, the pneumatic fluid above the hammer is expelled through an exhauster retained in the anvil and out through the drill bit where it is utilized to transport the cuttings from the hole being drilled. The feeder operates in conjunction with the hammer to control pressurization above and below the hammer, while exhaust above the hammer is controlled by the lower end of said feeder tube.

Abstract: An impact and rotary rock drilling tool for operation by compressed air fed through a three-part control unit that contains a valve and duct system and is housed in a cage mounted to an outer tube. A central spindle tube is positively connected to the control unit and guides a main ram as well as an intermediate ram that rests on top of a steel drill member for reciprocating movement therewith. An insert portion secured inside the central spindle tube, which latter may comprise a check valve at its lower end, has partitions separating a plurality of passages with ports arranged in the central spindle tube for selected flow connections.

Abstract: A down-the-hole rock drill including a drill bit provided at the lower end of a drill rod, which is rotatably driven by an above-the-ground motor. To increase the drilling efficiency and facilitate drilling of large-diameter holes a machine casing is positioned between the drill rod and the drill bit, said casing enclosing a hydraulic pump which is rotatably driven by the drill rod. The hydraulic pump delivers pressurized liquid to and drives the percussion unit including a hammer, the latter delivering blows against the drill bit at regular intervals. The machine casing also encloses at least one hydraulic motor driven by the pressurized liquid and arranged to rotate the drill bit. Hydraulically controllable blocking means prevent the machine casing from rotating relative to the drill hole wall while the drill bit is in operation.

Abstract: The drill has a housing receiving therein a reciprocating striker, effecting percussive action upon the tool for breaking the rock at the face of the hole, mounted at the forward part of the housing, and upon the housing itself for propelling the drill in the hole. The housing also receives therein a mechanism for rotating the tool, including a self-controlled coupling provided with a movable sleeve and a stationary sleeve and adapted to transmit a torque to the tool in only one direction of rotation. The drill is provided with a device preventing a rearward motion of the housing and its rotation during a drilling operation. The drill is characterized by having a return device for retracting the tool from the face after it has been struck by the striker.

Abstract: A down hole percussion drill having an inner tube located within an outer tube guiding a ram for reciprocating movement relative to a drill steel. The drill steel and/or a wear bit secured thereto as well as retainers for them are provided with matching disharmonic polygonal profiles for sliding fit under load, free of edge pressure and with full power transmission by the lateral faces. The outer tube top end and a piston therein may have like polygonal connection. The inner tube is rigidly attached in the center of the outer tube by a unitary supporting head into which a coaxial control cylinder projects that has a valve seat for a mushroom valve with peripheral notches at its outer edge and further has an inner control tube with a slidable spring-loaded control sleeve for governing pneumatic fluid through suitable flow links.

Abstract: A percussive rock drill and more particularly a percussive rock drill having improved means for passing a flow of flushing fluid therethrough.

Abstract: An air hammer embodying an outer housing structure connectable to a rotatable drill pipe string through which compressed air is conducted. A hammer piston reciprocates in the housng structure, compressed air being directed alternately to the upper and lower ends of the piston to effect its reciprocation in the structure, each downward stroke inflicting an impact blow upon the anvil portion of an anvil bit extending upwardly within the lower portion of the housing structure. The compressed air exhausts through a non-metallic elastic synthetic resin sleeve or tube fixed to the anvil and extending slidably into the lower portion of the hammer piston, the sleeve being deflectable laterally in the event of misalignment between the hammer piston and the anvil to prevent fatigue failure of the sleeve.