Abstract: A vacuum motor has a piston that linearly oscillates in the internal space of a housing. A gas outlet and a gas inlet (supplying ambient air) located in the housing terminate in the space between the piston and the housing rear side. The piston never covers the outlet or inlet. A valve body closes the inlet. A pestle moves within the housing between the piston and valve body. When the piston moves toward the rear side of the space, the valve body moves against the force of a spring and opens the inlet. The free cross-section of the opened inlet is at least equal in size to the free cross-section of the outlet. A surgical drive system, a medical lavage system, and a medical device for brushing, rasping or sawing of tissue or bone—all include the vacuum motor. Also disclosed is a method for operating the vacuum motor.

Abstract: A system for testing load-bearing and durability of a sliding rail includes a chassis, a sliding rail mounted on the chassis, a sliding member installed on the sliding rail, and a reciprocating driving device. The reciprocating driving device includes a control unit, a reversing unit, and a driving unit connected to the reversing unit. The driving unit drives the sliding member and the control unit outputs control signals to the reversing unit to periodically reverse driving direction of the driving unit, according to the control signals. The reciprocating driving device is also disclosed.

Abstract: A fluid pressure driven, high frequency percussion hammer for drilling in hard formations is presented. The hammer piston (20) of the percussion hammer has a relatively large and longitudinally extending bore (41) that provides minimal flow resistance for a drilling fluid flowing through the bore (41) during the return stroke of the hammer piston (20). The bore (41) is closeable in the upstream direction by a valve plug (23) that follows the hammer piston (20) during the stroke. The valve plug (23) is controlled by a relatively long and slender valve stem (49) that is mechanically able to stop the valve plug (23) by approximately 75% of the full stroke length of the hammer piston (20) and separates the plug (23) from a seat ring (40). Thus the bore (41) opens up such that the bore fluid can flow there trough, and the inherent tension spring properties of the valve stem (49) returns the valve plug (23) so rapid that it will be good through flow during return of the hammer piston (20).

Abstract: A fluid pressure driven, high frequency percussion hammer for drilling in hard formations is presented. The hammer piston (20) of the percussion hammer has a relatively large and longitudinally extending bore (41) that provides minimal flow resistance for a drilling fluid flowing through the bore (41) during the return stroke of the hammer piston (20). The bore (41) is closeable in the upstream direction by a valve plug (23) that follows the hammer piston (20) during the stroke. The valve plug (23) is controlled by a relatively long and slender valve stem (49) that is mechanically able to stop the valve plug (23) by approximately 75% of the full stroke length of the hammer piston (20) and separates the plug (23) from a seat ring (40). Thus the bore (41) opens up such that the bore fluid can flow there trough, and the inherent tension spring properties of the valve stem (49) returns the valve plug (23) so rapid that it will be good through flow during return of the hammer piston (20).

Abstract: A pneumatic tool has a hollowed main body. One end of the main body is assembled with a pneumatic motor having a transmission shaft inserted into the main body. The other end of the main body is assembled with a connecting member being slidable along an axial direction of the main body. One end of the connecting member forms a connecting portion, and the other end of the connecting member forms a knife assembling portion. A driving gear is rotatably assembled in the main body and engaged with the transmission shaft. A protruding post is assembled on a portion of the driving gear biasing from an axis of the driving gear. A linking bar has a first end and a second end opposite to the first end. The first end is pin-jointed to the protruding post, and the second end is pin-jointed to the connecting portion of the connecting member.

Abstract: An apparatus, system, and method of fabricating a percussion tool that includes a flow tube. The flow tube includes upper and lower portions, inner and outer walls, and at least one opening formed in the outer wall. The upper portion extends from a top end towards a bottom end. The lower portion extends from the upper portion to the bottom end. The inner wall extends from the top end to the bottom end and defines a central channel therein. The outer wall extends from the top end towards the bottom end, surrounds a portion of the inner wall and defines an outer channel with the inner wall. The opening is fluidly communicable with a first conduit formed within a piston, which surrounds a portion of the flow tube, when in an up position and is fluidly communicable with a second conduit formed within the piston when in a down position.

Abstract: A clamp assembly for a pile driving system for driving a concrete sheet pile, the clamp assembly comprising a clamp body, a first clamp member supported relative to the clamp body, and a second clamp member supported for movement relative to the clamp body, and a bumper member. A clamp region is formed between the first and second clamp members. The bumper member is supported relative to the clamp body above the clamp region. The clamp body is configured such that the concrete sheet pile enters the clamp region from below. The second clamp member is displaced towards the first clamp member to engage the concrete sheet pile in the clamp region. The bumper member resiliently deforms to inhibit direct transmission of forces between the concrete sheet pile and the clamp body during driving of the concrete sheet pile.

Abstract: A diesel hammer pile driver has a cylinder, a piston displaceably guided in the cylinder and a striker displaceably guided in the cylinder. The striker is disposed underneath the piston in the operating position of the diesel hammer pile driver. A combustion chamber is delimited axially by a face surface of the striker that lies in the interior of the cylinder and by a face surface of the piston, and opens into a fuel feed device connected with a fuel tank disposed on the outside of the cylinder. Using the fuel feed device a predetermined amount of fuel can be introduced into the combustion chamber during each working cycle. The fuel tank is elastically mounted on the cylinder.

Abstract: A diesel hammer pile driver has a cylinder, a piston displaceably guided in the cylinder and a striker displaceably guided in the cylinder. The striker is disposed underneath the piston in the operating position of the diesel hammer pile driver. A combustion chamber is delimited axially by a face surface of the striker that lies in the interior of the cylinder and by a face surface of the piston, and opens into a fuel feed device. Using the fuel feed device a predetermined amount of fuel can be introduced into the combustion chamber during each working cycle. At least two working connectors are disposed to pass through the circumference wall of the cylinder at the level of the fuel feed device, wherein at least one working connector is provided with a muffler device.

Abstract: A pile-driving apparatus includes a diesel hammer pile driver having a cylinder, and a piston and a striker displaceably guided therein. A combustion chamber opens into a fuel feed device for introducing a predetermined amount of fuel into the combustion chamber during each working cycle. A disengagement apparatus axially displaceable on the cylinder outside is disposed within the cylinder, to raise the piston, has a driver introduceable into a piston undercut, through a piston recess, and has an operating lever for pivoting the driver into the cylinder space if a collision with the engagement cam occurs. A disengagement cam on the cylinder above the engagement cam pivots the driver out of the cylinder space if the operating lever collides with the disengagement cam. The engagement cam and/or the operating lever is configured for movement out of the collision region of the operating lever or of the engagement cam.

Abstract: A percussion device has a machine housing (1), a forwards and backwards movable percussion piston (2) in the machine housing, and a reciprocatingly movable valve body (6) in the machine housing. The percussion piston has a first (4) and a second (5) driving surface subjected to pressure to drive the percussion piston (2) forwards and backwards. The valve body (6) has a first end surface (12) and a second end surface (13) for driving the valve body in first and second directions by applied pressure. The valve body (6) is arranged over a channel (7) in the machine housing, to connect at least the second (5) driving surface alternately to a pressure source (8) or to low pressure (9), and the second end surface (13) is alternately connectable by the percussion piston (2) to the pressure source (8) or, over a valve device (11) for creating a counter-pressure, to the low pressure (8).

Abstract: A hydraulic hammer includes a powercell housing that defines a hydraulic inlet and a hydraulic outlet. A work tool is partially received in, and movable with respect to, the powercell housing. A switching spool valve member is positioned in the powercell housing and is movable between a first position and a second position, and includes a control hydraulic surface. A sleeve/liner assembly is positioned in the powercell housing and defines a centerline. A piston with a plurality of hydraulic surfaces is positioned in the sleeve/liner assembly and is movable along the centerline between positions in and out of contact with the work tool. The control hydraulic surface of the switching spool valve member is exposed to fluid pressure in a switching passage, which includes a segment defined by the sleeve/liner assembly.

Abstract: A fluid powered percussion tool 1 has a housing 2 with a supply channel for pressurized fluid 3, a percussion mechanism 4, a swing joint 5 arranged to carry the percussion mechanism 4 relative to the housing 2 at a point situated between the forward end A and the rear end B of the percussion mechanism 4, at least one elastically resilient element 6 arranged between the housing 2 and the percussion mechanism 4 at a distance from the swinging joint 5 and arranged to load the percussion mechanism 4 against a neutral position in the housing 2 and to absorb the vibrational movements of the percussion mechanism 4, and a flexible connection for pressurized fluid 7 for distribution of pressurized fluid from the supply channel for pressurized fluid 3 to the percussion mechanism 4. The elastically resilient element 6 includes a conical spring 8. The flexible connection for pressurized fluid 7 includes a hose 11.

Abstract: A rock drilling machine with a first control means (21, 22) within a second piston (6) and acting on a first piston (13) such that it counteracts displacement of the relative positions of a first and a second control device at the moment of contact of the second piston onto the drill rod or onto a part (9) connected to this. Furthermore, a rock drill rig comprising such a rock drilling machine and a method for counteracting the said displacement. Significant improvements in reproducibility for impact mechanism stability over long manufacturing series are achieved through the invention. In the same way, the lifetime of rock drilling devices manufactured according to the invention is extended through the impact mechanism acting in a more stable manner despite wear of component parts. It is furthermore possible to dimension for higher rates of impact without risking the impact mechanism stability.

Abstract: A recoilless hammer comprising a moil supported for reciprocal movement along a hammer axis of a housing, a piston moveable within the chamber of an elongate tube extending from the rear of the housing such that it may strike the moil. In a rest position the piston is held forward against the moil by a low pressure air supply delivered from the aft end of the chamber, and the piston is retracted to a charged position at the aft end of the chamber by delivery of high pressure air to act on the fore portion of the piston. Upon actuation of a trigger mechanism, air is vented from the fore end of the chamber to atmosphere causing a pressure unbalance of low magnitude across the piston, such that it accelerates towards and strikes the moil. The chamber is of a length to enable a high energy blow with minimal piston acceleration recoil when the hammer is manually held and operated.

Abstract: A percussion apparatus driven by a pressurized incompressible fluid includes a body with two coaxial bores for slidably mounting of a tool, and separately slidably mounting a striking piston having a stepped configuration. A control device varies a stroke of the striking piston between a long and a short stroke, and is connected to the directional flow valve and to a bottom chamber of the piston cylinder. The control device includes a cylinder in which a spool is mounted. A first face of the spool is situated in a first chamber permanently subjected to a determined pressure, and a second face of the spool is situated in a second chamber connected to the braking chamber for controlling the varying of the stroke of the striking piston.

Abstract: A percussive device and method having, inside a machine housing (3), a reciprocally moveable percussive piston (2), the movement of which is controlled by a control valve (5), which is arranged to alternatively connect a chamber to a pressure source and to low pressure in dependence on a signal corresponding to the axial position of the percussive piston, and a valve (16) arranged to allow adjustment of the axial position of the percussive piston at which the signal is transmitted, by opening and blocking of a connection between one or more control channels (10, 11, 12, 13) and the control valve.

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 percussion drill, and methods of using the same, including a shank in mechanical alignment with a piston-hammer and a valve in fluid communication with the piston-hammer. The percussion drill further includes an internal hydraulic dampening system for reducing the velocity of the piston-hammer when the shank is forward of a power position relative to the velocity of the piston-hammer when the shank is in a power position. Preferably, the internal hydraulic dampening system includes mechanical alignment of a portion of the piston-hammer with a port in fluid communication with the valve, operable to reduce fluid flow into an area surrounding the valve when the piston-hammer is forward of its position relative to its normal operation.

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 device for driving various objects using combustible fuel. Embodiments are contemplated in which the driver could be a post-driver, a power shovel, a jack-hammer or other devices. Typically, the device includes a body with a combustion chamber. A fuel injection valve selectively supplies fuel to the combustion chamber where it can be ignited using an ignition module. A piston is movable within the body to impact the ram responsive to combustion in the combustion chamber.

Abstract: A fluid distributor cylinder is for a percussive drill assembly that includes a casing having an inner circumferential surface defining a central bore, a central axis extending through the bore, a bit movably coupled with the casing and a piston movably disposed within the casing bore. The distributor cylinder includes a generally tubular body disposeable within the casing bore and having first and second ends, a central axis extending generally between the first and second ends, an outer circumferential surface. At least a section of the outer surface is configured to engage with the inner surface of the casing so to form an interference fit between the body and the casing. The cylinder includes an exterior thread and/or a radially-extending shoulder configured to releasably engage with the casing inner surface so as to substantially prevent axial displacement of the distributor body with respect to the casing.

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: The invention relates to a diesel pile hammer (10) which comprises a cylinder (12), a piston (14) slidably mounted inside the cylinder (12), and an impact piece (16) slidably mounted inside the cylinder (12), said impact piece being arranged below the piston (14) in the operating position of the diesel pile hammer (10). A working compartment (32) is axially delimited by a face (36) of the impact piece (16) lying inside the cylinder (12) and a face (46) of the piston (14). A fuel supply device (52, 55, 62, 68) feeds a defined amount of fuel, especially diesel oil, to said working compartment with every working cycle. The fuel supply device (52, 55, 62, 68) is configured to inject the fuel into the working compartment (32) of the cylinder (12) optionally in a first mode of injection as an atomized fuel spray (76) or in a second mode of injection as a fuel jet (74) or in a third mode of injection both as an atomized fuel spray (76) and as a fuel jet (74).

Abstract: Percussion device including a machine housing (1), a forwards and backwards movable percussion piston (2) in the machine housing, and a reciprocatingly movable tubular valve body (6) inside the machine housing, said percussion piston (2) being arranged to subject a tool (3) to impact, and said percussion piston including a first (4) and a second (5) driving surface arranged to be pressurized in order to drive the percussion piston forwards and backwards, said valve body (6) including a first end surface (12) and a second end surface (13), wherein pressurizing the first end surface (12) tends to drive the valve body in a first direction and pressurizing the second end surface (13) tends to drive the valve body in a second direction, whereby the valve body (6) is arranged, over a channel (7) arranged in the machine housing, to connect at least the second (5) of the driving surfaces alternately to a pressure source (8) or to low pressure (9), wherein an inner room (31) in the tubular valve body (6) is continuous

Abstract: A hydraulic impact mechanism includes a housing with a cylinder bore, a forward working chamber and a rear working chamber, a hydraulic fluid supply passage connected to the forward working chamber and a drain passage connected to the rear working chamber, a hammer piston reciprocally guided in the cylinder bore for delivering blows to a working implement attached to the housing, a pressure accumulator pre-loaded to a certain pressure level, and a distribution valve for alternatingly connecting the rear working chamber to the supply passage and the drain passage to thereby reciprocate the hammer piston, wherein a sequence valve is provided in the drain passage to keep up the pressure in the rear working chamber so that the resulting forward directed force prevents the piston from being moved backwards in the cylinder bore at pressure levels in the supply passage below the pre-load pressure level of the accumulator.

Abstract: A drive system for driving and/or extracting an elongate member. The drive system comprises a piston drive assembly, a hydraulic system, and a vibration drive assembly. The piston drive assembly comprises a piston member, and the piston member engages the elongate member. The hydraulic system is operatively connected to the piston drive assembly to apply a drive force to the piston member. The vibration drive assembly generates a vibratory force. The vibration drive assembly is operatively connected to the piston drive assembly. The drive system operates in a first mode in which the drive force and the vibratory force are applied to the piston member along a drive axis.

Abstract: An impact hammer drill capable of performing drilling operation at a high speed with low noise and without requiring a large thrust. The drill includes a main shaft rotatable by an output shaft of a motor, and a spindle having an impact-receiving section and disposed over the main shaft slidably in its axial direction and rotatable together with the rotation of the main shaft. A piston is reciprocatingly slidably disposed over the main shaft for impacting against the impact-receiving section. A piston drive unit is disposed for driving the piston with a compressed fluid. A compressed fluid supplying unit is disposed for supplying the compressed fluid to the piston drive unit. A drill bit is attachable to the spindle. When performing drilling operation, the drill bit is imparted with a combined rotational motion and the reciprocal impact motion.

Abstract: An impact tool has a slidable hammer that is driven by hydraulic oil under pressure inside a chamber. The hydraulic oil is pressurized by a piston driven by compressed gas on the opposite side of the piston from the hydraulic oil. The gas in the gas chamber is compressed by the piston on an initial stroke, and has a large annular chamber holding the gas so that higher average gas pressure can be attained during the power stroke. As the piston is moved to compress the gas, the piston lifts a valve that opens a passage for the hydraulic oil moved by the piston to act on a hammer to impact a breaking tool. The piston is a two part piston that serves to lower the inertia during the final closing of the valve, and thereby reduces impact loads on the valve as it is closed. The valve also is controlled as to its stroke for efficient operation.

Abstract: A power source (10) for providing energy to drive a mechanical device including a receiving chamber (11) and discrete propellant charges (23) for selective detonation whereby gases generated by the selective detonation expand into the receiving chamber (11) wherein said receiving chamber includes a reactive closure (15) which dynamically responds to pressure changes in the receiving chamber and wherein said power source further includes a linkage (16) associated with the reactive closure for transmitting energy from the dynamic response of the reactive closure to the mechanical device.

Abstract: A hydraulic drill string device can be in the form of a percussive hydraulic in-hole drilling machine that has a piston hammer (50) with an axial through hole (51) into which a tube (35) extends. The tube forms a channel for flushing fluid from a spool valve (62) and the tube wall contains channels (40) with ports (41,42) cooperating with the piston hammer for controlling the valve.

Abstract: A diesel hammer system for driving a pile, comprising a housing, an anvil member supported by the housing, a clamp assembly adapted to connect the anvil member to the pile, and a ram member disposed within the housing. A fuel pump system injects fuel into a combustion chamber defined by the housing, anvil member, and the ram member. A coupling system detachably engages the ram member to raise the ram member from an impact position to an upper position, the coupling system comprising a trigger member that, when engaged, causes the coupling system to release the ram member. A trigger projection mounted is on the housing to engage the trigger member to cause the coupling system to release the ram member at the upper position. The diesel hammer further comprises a pre-trigger system comprising a pre-trigger member movable between an extended position and a retracted position.

Abstract: A drive system for driving a sheet pile member at a desired location in the ground. The drive system comprises a source of pressurized air, an actuator system defining a drive axis, and an adapter member. The actuator system comprises a housing assembly having an inlet port connected to the source of pressurized air and a piston member adapted to move along the drive axis relative to the housing assembly. The adapter member is rigidly connected to the housing assembly. The adapter member further defines at least a first pair of first and second guide slots. In use, the sheet pile member is arranged at the desired location. The adapter member is arranged such that the first and second guide slots at least partly receive portions of the sheet pile member. The pressurized air causes the piston member to move along the drive axis.

Abstract: A post driving implement for use with a vehicle, such as a tractor or a skid loader, is disclosed. The post driving implement is comprised of a hammer, a hammer channel, and a hammer cylinder. The hammer travels longitudinally within the hammer channel and is lifted by the hammer cylinder mounted to a closed end of the hammer channel. The hammer cylinder and its associated plumbing is of sufficient size to function as a hydraulic reservoir for the post driving implement, thus eliminating the need for a third hydraulic line to the reservoir on the vehicle and to avoiding need for alteration of the vehicle's reservoir. The post driving implement of the present invention may also include a back plate for mounting the implement to a vehicle. Additionally, the post driving implement may include adjustment mechanisms to vary the positional and angular relationship between the vehicle and the implement.

Abstract: A method for controlling the operating cycle of an impact device, and an impact device. Percussion piston position is measured using a sensor (11) from which the measurement data is transmitted to a control unit (12) of the impact device, which in turn controls an electrically driven control valve (10).

Abstract: A diesel hammer system for driving piles. In one form of the invention, a control pinion is attached to a cam member employed to adjust the volume of a fuel portion of a pump chamber. A control rack is arranged to engage the control pinion such that linear movement of the control rack is translated into rotational movement of the control pinion. A hydraulic cylinder assembly is provided having a control housing and a control piston. The control piston is attached to the control rack such that linear movement of the control piston is transferred to the control rack. Hydraulic fluid is introduced into the control housing to cause linear movement of the control piston. Conventional hydraulic controls may be used at a remote location to introduce hydraulic fluid into the appropriate portions of the control housing chamber. In another form of the invention, indicia are formed on a housing of the variable fuel pump to allow an operator to see the setting of the fuel pump.

Abstract: A fastener installation tool to install fasteners, such as rivets, risers, standoffs, and other types of fasteners operates upon vacuum and air pressure. Fasteners are installed with minimal reactive forces to the operator's hand, thus reducing the risk of repetitive injuries to the operator's body. Vacuum retains the fastener within the tool tip and retracts a piston, until an operator simultaneously presses the fastener against a work piece and actuates an actuation element on the tool. This causes air pressure to quickly thrust the piston against a hammer pin to drive in the fastener, transferring kinetic energy from the piston to the fastener without appreciable kick-back to the operator. A control system provides a source of vacuum and air pressure to the tool. Methods of using a fastener installation tool are also described.

Abstract: There is provided drilling apparatus (10) comprising a hammer casing (11), a free piston motor piston guide and porting sleeve (12), a drive sub (13), a drill bit (15) splined by shank (16) to the drive sub (13). Below the splined portion (17) the drive sub is relieved at (23) to form an annular air space for motor exhaust air from the splines (16) and (17). The drive sub (13) retains a gauge sleeve (24) via an annular flange (25) between the hammer casing (11) at (26) and a shoulder (27) on the drive sub (13). Below the shoulder (27) the outer diameter of the drive sub (13) is provided with eight grooves that form conduits (30) with the lower portion (31) of the gauge sleeve (24) extending parallel to the drill axis in communication with the space (23) via ports (32). The lower portion (31) extends down the side of the drive sub (13) and terminates with it at (34) adjacent the shoulder (33) at the transition from the bit shank (16) and the bit head (35).

Abstract: A down-the-hole percussive hammer includes a casing, a drill bit attached to a lower end of the casing, and a reciprocable hammer for impacting against the drill bit. A top sub attached to an upper end of the casing includes a central passage for conducting operating air for actuating the piston. A feed tube is attached to the top sub and extends along a center axis thereof. The feed tube includes vertically spaced outlet and re-entry ports sealed from one another by a seal disposed inside of the feed tube. The outlet and re-entry ports communicate with a chamber formed in the central passage. A check valve is disposed at an upper end of the feed tube. The check valve includes an elastic sleeve arranged to overlie the outlet port and to be elastically biased away from the outlet port by pressurized operating air, whereupon the operating air passes out of the feed tube through the outlet port and then back into the feed tube through the re-entry port.

Abstract: A vibratory impact tool for loosening downhole stuck objects in oil or gas wells, utilizing an internal piston spring which is repeatedly compressed by hydraulic pressure, and repeatedly released by lifting a dart valve from a valve seat on a flow-through piston. When the dart valve is lifted from the valve seat by a tripping spring, flow resumes through the piston, quickly lowering hydraulic pressure above the piston, allowing the piston spring to sharply drive the piston against the housing. The dart valve is then reseated on the valve seat, causing the piston to again be driven against the piston spring, rapidly repeating the process.

Abstract: A motor housing (11) is mounted in a handle body (10) so as to slide in the longitudinal direction. A tubular pipe (37) that can slide in a bore (38) of the body (10) projects from the back of the housing (11). Compressed air can be applied to the bore (38) through a switching valve (40). A piston (14) with a piston rod (17) can slide in the housing and a tool can be secured to its front end. A flutter valve (23) which alternatingly connects the bore (38) to the two cylinder chambers (27, 28) is built into the valve housing (22). The piston (14) alternatingly opens the connection to an outgoing air conduit (29-31). A pre-stressed spring (47) is set between the body (10) and the housing (11). In operation, the housing (11) oscillates out of step with the piston (14), so that their initial forces are largely compensated and no vibrations are transmitted to the handle body (10).

Abstract: A drill head for an apparatus for directional boring includes a bit having a cutting portion for use in steering, such as a gage tower mounted with carbide studs, suitable for cutting both hard and soft rock, a holder for a device for detecting angular orientation of the bit, and a pneumatic hammer connected head to tail with the bit at the front end. The valve in the hammer initiates reciprocation of the hammer in response to rearward movement of the bit, such as in response to a pushing force exerted by the drill string. The drill string components are preferably keyed to one another so that the orientation of the cutting portion of the bit used for steering is automatically matched to the position of the sonde. The sonde may project laterally so that its mass centroid is on the opposite side of the cutting portion of the bit used for steering to provide better cutting action. Such a drill head is suited for drilling in soil, soft rock and hard rock conditions.

Abstract: A hydraulic percussion drill includes a piston hammer disposed in a cylinder for reciprocating movement in response to pressure fluid acting continuously on one transverse face of the piston hammer and in response to valving of pressure fluid alternately to an opposed piston face of the piston hammer by a tubular sleeve valve disposed around the piston hammer. The drill includes a percussion bit configured to have a face portion disposed at an acute angle with respect to a plane normal to the bit and the drill central axis. Cooperating spiral splines on the bit and a bit chuck provide for directional drilling using a method which includes causing the bit to receive impact blows without rotating the cylinder housing to initiate a deviated drillhole.

Abstract: The invention concerns a down the hole drill hammer assembly providing a full piston area exposure to driving fluid pressure by the omission of the usual finger valve from the upper piston area and providing the piston with blind bores at each end and passages through the piston wall enabling predetermined communication between the blind bores for exhausting pressure fluid through the drill bit assembly. Fluid transfer passages are also provided in the inner wall of an outer wear sleeve of the drill hammer assembly.

Abstract: The invention relates to an arrangement in connection with a hydraulic breaking apparatus, the arrangement comprising a housing (4) placed around a percussion hammer (1), and a changeable wearing element (6) arranged at the lower part of the housing. The wearing element (6) receives blows and forces directed at the lower part of the housing (4). The wearing element (6) is fastened in such a way that it can be detached and changed easily and rapidly, if required. Further, the structure of the breaking apparatus may also be such that when the wearing element (6) is removed, it is possible to carry out the maintenance and repair operations of the lower frame (1b) of the percussion hammer without disassembling the upper frame (1a) of the percussion hammer.

Abstract: A drill head for an apparatus for directional boring includes a bit having a cutting portion for use in steering, such as a gage tower mounted with carbide studs, suitable for cutting both hard and soft rock, a holder for a device for detecting angular orientation of the bit, and a pneumatic hammer connected head to tail with the bit at the front end. The valve in the hammer initiates reciprocation of the hammer in response to rearward movement of the bit, such as in response to a pushing force exerted by the drill string. The drill string components are preferably keyed to one another so that the orientation of the cutting portion of the bit used for steering is automatically matched to the position of the sonde. The sonde may project laterally so that its mass centroid is on the opposite side of the cutting portion of the bit used for steering to provide better cutting action. Such a drill head is suited for drilling in soil, soft rock and hard rock conditions.

Abstract: A damper pressure control apparatus for a hydraulic rock drill is automatically adjustable of damper pressure to be applied to a damping piston depending upon a thrust of a rock drill body and makes damping function and floating function effective even when thrust of hydraulic rock drill is varied. The damper control apparatus is thus provides a damper pressure control for controlling the damper pressure (DPpr) to be applied to a damping piston (16, 17) from a hydraulic pressure source (21) based on the frontward thrust (F1) acting on the hydraulic rock drill body 1.

Abstract: When cutting metal rods, for instance, percussion machines are used that utilize stored kinetic energy which has been produced either mechanically or by the use of compressed gas. A drawback is the inability to accurately control the cutting process. The present invention makes use of hydraulics to control the process, thereby achieving total control of the course of the function.

Abstract: A system for drilling a horizontal bore through frangible material includes a barrel mechanism containing a automatically reciprocating piston mechanism for automatically delivering hammering blows to a bit for chipping away the frangible material, a fluid distributor for directing fluid to and exhausting pressurized fluid from the piston mechanism without exposing the wall of the bore being created to fluid pressure greater than ambient atmospheric pressure, a spline/flute arrangement for causing the bit to rotate with the barrel mechanism, a motor and swivel mounted on a driven platform mounted on a supporting frame for urging the bit against the frangible material and for supplying the pressurized fluid, a pushing mechanism for non-rotatingly and simultaneously installing casing joints as various components of the system is rotatingly drilling the bore, an augering arrangement for, in conjunction with the casing joints, removing the drilling debris, and drill/auger stem sections for extending the drilling

Abstract: For selective operation in a Diesel mode and a pressure air mode a Diesel type pile hammer is additionally equipped with a pressure air accumulator, which is connected to the working space of the cylinder by a servo valve.