Abstract: A cushion device of a pneumatic tool has a body, a cushion, and a piston assembly. The body includes a containing portion which has a bottom surface. The cushion is mounted in the containing portion of the body, is formed cylindrical, and has an axial direction, two end surfaces, an interior, an exterior, and at least one passage. The two end surfaces are separately located along the axial direction, and one of the two end surfaces abuts against the bottom surface of the containing portion. The at least one passage is disposed on the cushion, and communicates with the interior and the exterior. The piston assembly is movably mounted to the containing portion of the body and has a base and a cylinder. The base has an abutting portion abutting against the other one of the two end surfaces of the cushion. The cylinder is connected with the base.

Abstract: The A hand-held power tool includes a tool holder 2 for holding a tool and a pneumatic striking mechanism for periodically generating impacts on the tool held in the tool holder. The striking mechanism includes a guiding tube, an exciter piston, a striker, a pneumatic chamber closed by the exciter piston and the striker in the guiding tube, and a compensating opening in the guiding tube for ventilating the pneumatic chamber. A cap covers the compensating opening on an outside of the guiding tube. The cap is open in an opening direction which is largely tangential to the guiding tube.

Abstract: An impact tool includes a tubular tool holder, a hammering mechanism, a resistor, and a biasing member. An impact element moves forward and rearward in conjunction with a piston. An intermediate element is housed movable back and forth between the impact element and a tip tool. The intermediate element abuts on a rear end of the tip tool to indirectly transmit a striking force from the impact element to the tip tool in a normal striking. The resistor is configured to abut on at least one of the intermediate element and the tip tool to apply a resistance to a front-rear movement of at least one of the intermediate element and the tip tool in a non-striking state. The biasing member disposed on the tool holder biases the resistor to a side of at least one of the intermediate element and the tip tool.

Abstract: The present invention is directed to a dynamic seal tube for use in pressurized fluid-driven down hole hammer drills. The dynamic seal tube is a tube that slides within the bore of the piston and the anvil portion of the drill bit and co-operatively acts to release different volumes of pressurized fluid from the lower chamber when the piston is in different predetermined positions.

Abstract: Impact tool and method for a hammer device that includes impact tool housing and tubular piston structured and arranged for axial displacement in impact tool housing via pressure medium. Tubular piston has essentially radial pressure surfaces structured and arranged on opposite portions of tubular piston to be acted on with pressure medium. Grooves are formed in impact tool housing that are structured and arranged for a reversal of a direction of a pressure medium impingement on pressure surfaces and discharge or recirculation of medium. Grooves include a control recess formed in tubular piston and at least two control grooves for a shift of pressure medium impingement on pressure surfaces that are arranged axially offset in impact tool housing. A controller is structured and arranged to alternatively activate one of the at least two control grooves via connection channels.

Abstract: A drive point for a substantially tubular, in particular hollow cylindrical, driven pile having a pile core through which concrete can be introduced into the driven pile, wherein the drive point can be fitted onto a pile end of the driven pile, wherein at least one first supporting web with a first contact surface for an end face of the pile end is arranged on an inner wall of the drive point, wherein starting from a plane of a first bearing surface the drive point has a cavity which extends at least partially in a driving direction and into which concrete can be introduced through the pile core when the driven pile is fitted, wherein at least one concrete outlet channel is provided which connects the cavity to an upper edge of the drive point.

Abstract: A drilling apparatus including a drill bit and a nutation device. The drilling apparatus is configured to enable the drill bit to be rotated at a rotation frequency while the nutation device simultaneously nutates the drill bit at a nutation frequency. The nutation device may include a vibrating device for imposing vibrations upon the drilling apparatus at a vibration frequency, thereby causing nutation of the drill bit at the nutation frequency. The drilling apparatus may include a tuning mechanism for tuning the vibration frequency of the vibrating device. A method including rotating a drill bit at a rotation frequency and simultaneously nutating the drill bit at a nutation frequency.

Abstract: The optimized soil penetrating machine is characterized by parameters that are optimized with respect to maximum kinetic energy that the machine cyclically obtains for soil deformation during the forward mode of operation. The optimization of the parameters is based on the author's analytical investigation that revealed the existence of the optimal values of the lengths of the striker and its forward stroke at which the machine's kinetic energy reaches its maximum value, resulting in the maximum performance efficiency. The investigation shows that the optimal value of the length of the striker is shorter than the length of its forward stroke. In the existing machines the striker is longer than its forward stroke. This investigation also shows that the efficiency of the existing machines is about 2.5 times less than for their optimized hypothetical counterparts. Since the existing machines cannot be optimized it is required to implement new design concepts.

Abstract: A downhole tool including a fluid-actuated piston and a motor-driven valve. The fluid-actuated piston is operatively associated with a reciprocating mass. The motor-driven valve is configured to supply actuating fluid sequentially to drive the piston downwards and upwards. A method of reciprocating a mass in a downhole tool. The method including cycling a motor-driven valve between a first configuration and a second configuration. In the first configuration actuating fluid pressure drives a piston associated with the mass downwards. In the second configuration actuating fluid pressure drives the piston upwards.

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: Pressure-air driven percussion device for a down-the-hole drill with a hammer-piston which is axially reciprocally movable in a hammer-piston chamber through a driving device. The hammer-piston in operation acting with a hammer-end against an upper end of a drill bit which is positioned inside a chuck. An air-cushion for reducing percussive power is arranged to be formed at the hammer-end of the hammer-piston in positions where the drill bit has been moved past a predetermined distance in the percussion direction. The drill bit is sealingly slidingly supported in a drill bit bushing, and the hammer-end of the hammer-piston is formed so that it sealingly cooperates with the drill bit bushing in the positions in order to form the air-cushion.

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 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 drill hammer or riveter, includes a housing (11), in which a hammering mechanism (12) is accommodated that in an axially displaceably supported guide tube (13) has a reciprocating piston (16) and a striker (17), drivable by the piston (16) via an air cushion; the hammering mechanism (12) can be moved out of an idling position into a hammering position by an axial displacement of the guide tube (13); the guide tube (13) is urged by a restoring spring (27) in the direction of the idling position with a restoring force: and between the guide tube (13) and the housing (11), at least one damping and/or spring member (30, 36, 37) is provided, which in the hammering position of the guide tuber (13) has a spring or damping characteristic between the guide tube (13) and the housing (11) that deviates from the restoring spring (27) in the region of the idling position.

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 fluid-powered percussion tool includes a percussion piston which, under the effect of a control alternately performs a working stroke and a return stroke with the aid of a control valve. The control valve assumes a working stroke or a return stroke position, depending on the position of the percussion piston. In the working stroke position, the percussion piston is admitted with working pressure such that it performs a working stroke counter to the effect of a continuous reset force. In contrast, the percussion piston is connected in the return stroke position to a discharge line so that it performs a return stroke under the effect of the reset force. The control valve is admitted during the working stroke with working pressure and is thereby held in the working stroke position.

Abstract: A double-acting hydraulic striking tool, wherein a hammer's (8) upper end (9) is rigidly connected to an upper piston (10), and wherein the hammer's (8) lower end (26) is rigidly connected to a lower piston (26). The pistons (10, 27), which can be displaced within a tubular housing (11), are adapted to open and close for a forced flow of liquid from the upper end (9) of the hammer (8) towards the lower end (26). The hammer (8) is activated for downwardly directed blows by pressing against the hammer's (8) upper end (9) with a resilient force, causing the lower piston (27) to close the liquid flow, whereby the housing (11) is lifted hydraulically until the piston (27) opens for the liquid flow, and the forced spring force drives the housing (11) downwardly to impinge on the hammer's (8) lower end (26) through impact faces (34, 36).

Abstract: The invention provides a method for reversing an impact boring tool of the type having a reversing mechanism actuated by rotation of the compressed air supply hose that enters the tool through a rear end opening. This method includes the initial step of connecting the air supply hose to the tool using a quick-release coupling device including tubular male and female members which are coupled together, one of the members being mounted on the end of the air supply hose and the other mounted on an air inlet conduit of the tool, the coupling device further having a locking sleeve and a ball seated in a first pit in one of the members and configured for insertion into a second pit in the other of the members as the locking sleeve moves over the ball, the locking sleeve being biased to a locked position wherein the ball is seated in both pits thereby preventing rotation of one member relative to the other as well as disengagement of one member from the other.

Abstract: A pneumatic ground piercing tool according to the invention has a reversing mechanism provided as part of the air distributing mechanism. Such a tool includes an elongated tubular housing having a rear opening, a head assembly including an anvil, a striker disposed for reciprocation within an internal chamber of the housing to impart impacts to a rear impact surface of the anvil for driving the body through the ground, an air distributing mechanism for effecting reciprocation of the striker, and a tail assembly mounted in a rear end opening of the housing that secures the striker and air distributing mechanism in the housing. In one embodiment, the outer bushing of the valve sleeve can slide a short distance relative to the air supply tube and has an intermediate radial port which selectively communicates with the air supply conduit. The valve sleeve also includes a detent mechanism for securing the air supply tube in its forward or reverse position.

Abstract: Apparatus comprising a striking piston driven hydraulically in a reciprocating fashion by an incompressible fluid inside a cylinder and striking against a tool, of the type in which the piston slides in a cylinder having two concentric piston bearing surfaces of different sections, of which that situated on the tool side has a section smaller than that remote from the tool, the piston and the cylinder delimiting two antagonistic chambers, an annular bottom chamber and a top chamber of larger section.According to the invention the interior of the top chamber is permanently at a regulated pressure of a value intermediate between the inlet or high pressure and the outlet or low pressure, and the annular bottom chamber is connected alternately by a distributor to the high pressure supply circuit during the upward phase of the piston and to the top chamber during the accelerated downward phase of the piston.

Abstract: The invention represents a differential pneumopercussive self-propelled reversible soil penetrating machine (100) having essentially higher efficiency, reliability, durability, and controllability compared to conventional machines. All of these achievements are associated in part with the development of an innovative differential air-distributing mechanism (106) which inherently allows for relatively long strokes of the striker (104) resulting in relatively high impact energy of the striker. The operation of this mechanism is based on the difference between the pressures in the two separate nominal (high) and reduced (low) pressure air lines which deliver compressed air to the machine. In order to switch over the machine (100) from the forward to the reverse mode operation or vice versa it is just necessary to adjust properly the pressure in the reduced (low) pressure air line by a conventional air pressure regulator associated with the source of compressed air.

Abstract: The present invention provides a self-propelled impact boring tool which, according to one aspect of the invention, has a simplified tail assembly so that the tool can be readily assembled and dissambled to allow replacement of worn parts. Such a tail assembly includes a nut and an end cap which can be secured together by a series of conventional bolts which extend into threaded holes in the nut. The nut, which is screwed into the rear end of the tool body, can be clamped in position with the screws with far less torque than would otherwise be required with a conventional, unitary tailpiece.

Abstract: A fluid impact tool is disclosed of the type commonly known as a down-the-hole drill for drilling of rock. The improvement herein described increases deep hole drill performance by providing a means for accumulating piston return air in a traveling air pocket found on the piston. This effectively increases the piston front end volume so as to decrease the effect of the front end air cushion and thereby increase impact. This is particularly effective during operation with increased back pressure such as found in deep holes.

Abstract: A pneumatic impact tool wherein a two-stage piston is reciprocable in the two-stage chamber of a cylinder. The tool which is to penetrate into a bone is mounted in the front portion of the cylinder and the piston strikes against such front portion in response to admission of compressed air against its rear end face. A relatively small annular shoulder of the piston faces forwardly and is continuously acted upon by compressed air. When the piston approaches or reaches the end of its forward stroke and rebounds from the front end portion of the cylinder, it seals the source of compressed air from its rear end face so that the action of compressed air upon the shoulder suffices to propel the piston rearwardly against the rear end portion of the cylinder at which time the piston reestablishes a path for the flow of compressed air against its rear end face so that it is propelled forwardly against the front end portion of the cylinder.

Abstract: A percussive action machine includes a housing in which a hammer is movably secured to define a forward stroke chamber and a return stroke chamber. The hammer is provided with an air-distributor fashioned as a sleeve having holes. The hammer is further provided with a device for alternately communicating the return stroke chamber with the forward stroke chamber and with the outside, the device having the form of at least one bore arranged inside the hammer in line with its axis. Communicating with this bore is a tubular control valve extending through the forward stroke chamber and having in its wall at least one hole wherethrough the return stroke chamber alternately communicates with the forward stroke chamber and with the outside.

Abstract: A fluid operated hammer comprising; a casing; a top sub mounted to one end of the casing; a drill bit mounted to the other end of the casing; a feed tube located concentrically within the casing and extending for a portion of the length of the casing from said one end; and a piston slidably mounted in the casing for longitudinal movement between the top sub and drill bit over the feed tube; the feed tube being formed with at least one elongate aperture wherein the longitudinal dimensions of the at least one aperture correspond to a significant proportion of the degree of reciprocation of the piston; a first passageway provided in the piston and extending between the central bore and the external face thereof to provide a communication between the at least one aperture and the space between the piston and the top sub when the piston is at or near the top sub and for a significant proportion of the degree of movement of the piston from the top sub to a drive the piston towards the other end of the casing; a reb

Abstract: The present surgical tool uses high frequency impulses to replace rotating or oscillating members in cutting through or inserting materials into bone. One embodiment comprises a chisel which uses high frequency impulses to remove bone or other hard material. Because of the high forces developed, a novel holder for the chisel to the tool is disclosed. Another embodiment is a wire driver which uses high frequency impulses to drive wire into bone or other tissue. A novel holder for the wire is disclosed which allows wire to be pulled from the tool so that it can be inserted into the bone but prevents wire from slipping back into the tool during the driving operation. The chisel and the wire are driven by a novel pneumatic impulse motor. The motor includes a piston hammer which is mounted in a chamber, and air ports at either end of the chamber alternately direct air to one side of the piston hammer and to the other side of the piston hammer to drive it along the chamber.

Abstract: A casing hammer for driving casing while drilling a water well comprises a housing having an annular pneumatic chamber with a relatively lightweight, short-stroke annular piston. The piston is reciprocably driven at a high rate to provide a large number of light blows of controllable energy upon an annular anvil that seals one end of the chamber. Percussive blows upon the anvil are transmitted through a drive head and adapter to the upper end of the pipe to be driven. The hammer is suspended from a rotary drive head that operates a hollow drill string extending downwardly through the hammer and through the casing driven thereby.

Abstract: A pile driving ram for driving piles into subaqueous ground, during which a heavy piston operating as a hammer is each time lifted by fuel explosion in a cylinder, comprises a considerable and expensive cylinder piece, which has inlet and outlet ports and which comprises at least two guide girdles for supporting guide members co-operating with at least one guide stay of a guide frame. In order to increase the lifetime of the cylinder piece, the core is moulded from precious steel according to the fling moulding method.

Abstract: A pneumatic impact gun having an accumulator and interlock system for rapidly dumping a predetermined amount of compressed air into a cylinder to thereby propel an associated piston toward an anvil for contact with a rivet to be upset. The interlock system prevents accidental firing of the gun until a normally open interlock valve is manually depressed. Thereupon, a trigger valve may be manually opened to permit compressed air from a source to open a main valve and charge the accumulator to a predetermined pressure. The air in the accumulator may then be rapidly dumped therefrom into contact with the piston. Additionally, a metering valve serves as an energy selector to permit selective charging of the accumulator for varying the resulting impact of the piston onto the anvil.

Abstract: The apparatus has a pointed-nose hollow cylindrical body with a closed rear portion. Disposed inside the body, so as to enable reciprocation and rotation about the axis of the body, is a stepped striker which can be locked against rotation about the axis of the body in two positions, the positions corresponding to forward and reverse movement of the apparatus.For the purpose of admitting compressed air into a forward working chamber, the striker is provided with a central passage permanently connected to a rear working chamber and at least two radial passages which provide communication between the central passage and an outer cylindrical surface of a large step of the striker. The radial passages are displaced relative to each other both circumferentially and longitudinally along the axis of the body.

Abstract: A hand held impact tool is disclosed which employs an impact piston reciprocated by means of fluid pressure to impact a working tool. Fluid pressure is continually supplied to a pressure chamber forwardly of the impact piston such that a fluid cushion is established between the forward end of the piston and a piston stop surface resulting in substantial noise reduction. The working tool is biased outwardly of the tool housing by fluid pressure such that the working tool must be placed against an external object and moved axially inwardly to effect impact with the piston, whereby accidental ejection or unintentional operating movement of the working tool is prevented.

Abstract: A diesel pile driver with impact atomization of the fuel between pile driver piston and an impact member as well as with a fuel injection pump and an injector nozzle, which sprays fuel onto the impact member in the pile driver cylinder.

Abstract: A fluid actuated impact tool is disclosed of the type commonly known as a down-the-hole drill for drilling of rock. The tool is provided with a reversible casing which serves the dual functions of a casing and cylinder. A partial cylinder sleeve is utilized in conjunction with exhaust rod porting to provide a drill which is simple in construction, has a high energy level of output, and eliminates the need for expensive cross porting or axial porting in the parts most subject to wear; that is, the impact piston and the casing. All of the porting in the casing is accomplished by means of circumferential grooves which are readily machined.

Abstract: A pile driving device comprises one or more guide stays, a Diesel hammer, consisting of a combustion cylinder guided by guide means along each guide stay and a hammer piston operating in said combustion cylinder.Lifting the hammer piston at the start of the known pile-driving device takes place by means of a cable of a winch arranged at a large distance. In order to facilitate the starting the hammer piston is lifted by means of a hydraulic cylinder-piston set which via a catch engages the piston on the one hand and the combustion cylinder on the other hand.

Abstract: In a Diesel pile-driving ram comprising a combustion cylinder, a striker extending into the combustion cylinder, a piston housed in the combustion cylinder and a fuel injector for the supply of fuel between the impact surfaces of the piston and the striker, the impact surface of the striker is orientated in such a manner towards an annular precombustion chamber of a compression space provided between the piston and the striker, that the fuel atomized by impact ignites in the precombustion chamber. Said fuel, however, has too little air in said chamber in order to ignite immediately. The ignition is delayed for a moment but not too strongly because the precombustion chamber communicates with the main combustion chamber through an ample, annular passage of short length in an axial direction.

Abstract: An hydraulic rock drill having an hydraulically reciprocable hammer piston arranged to pound an anvil carrying a drill string. A sleeve type shiftable valve periodically engaged by the piston to effect alternate application to and relief of pressurized hydraulic fluid from the piston cylinder to reciprocate the piston. A constant supply of pressurized hydraulic fluid to actuate the piston is provided by a surrounding reservoir. Hydraulic feed means responds to a predetermined displacement of the anvil relative to the housing to feed the housing relative to the work in accordance with the progress of the anvil. Hydraulic means serves to cushion rebounding actions of the anvil; and means is provided to apply cooling fluid to the sliding surfaces of the tool during its operation.

Abstract: In a rammer a piston housed in a combustion cylinder strikes with its impact surface the adapted impact surface of a striker. When the impact surfaces are spherical or flattened the piston may strike against the cylinder wall, as a result of which the cylinder surfaces and the piston surfaces wear off strongly. In accordance with the invention the impact surfaces have a tangential cone having an obtuse apex so that on the one hand a sufficient centering of the piston with respect to the striker is obtained and on the other hand the risk of cracking in piston and striker is prevented.

Abstract: An underwater gas discharge type hammer is provided with a gas reservoir into which expended ram driving gas exhausts to avoid aeration of incoming water which surrounds the gas discharge device of the hammer. The gas resevoir is also arranged as a diving bell to minimize pressure changes under the hammer ram and thereby to maximize ram stroke and improve sharpness of ram impact on the hammer anvil.

Abstract: A ram device has a drop hammer connected to the piston of a lifting cylinder which is connected by means of short and wide ducts to a control apparatus for admitting compressed air into the cylinder and for discharging the air from the cylinder beneath the piston, control apparatus directly communicating with the ambient air so as to allow a rapid escape of the air through large air vent ports from beneath the piston. In particular this control apparatus is directly mounted on the cylinder, or is included in an extension of this cylinder.

Abstract: A pneumatic impact gun having an accumulator and interlock system for rapidly dumping a predetermined amount of compressed air into a cylinder to thereby propel an associated piston toward an anvil for contact with a rivet to be upset. The interlock system prevents accidental firing of the gun until a normally open interlock valve is manually depressed. Thereupon, a trigger valve may be manually opened to permit compressed air from a source to open a main valve thereby charging the accumulator to a predetermined condition to allow rapid dumping of compressed air therefrom into contact with the piston. Additionally, a metering valve serves as an energy selector to permit selective charging of the accumulator for varying the resulting impact of the piston onto the anvil.

Abstract: A machine having a housing wherein are arranged a hammer piston adapted for reciprocation in said housing to effect forward and return strokes and a stepped pressure difference ring valve fitted over the hammer piston and also reciprocating in said housing. A tool rotation mechanism is linked kinematically with a gear arranged on an anvil and has at least one twin hydraulic cylinder comprised of two different diameter cylinders and located at the front portion of the machine. The twin hydraulic cylinder is divided by a lateral partition and accommodates a pusher piston which carries a spring-loaded pawl and forms with the partition and the different diameter cylinder barrels two chambers, the smaller diameter chamber being the pressure one, the larger diameter chamber being the return chamber.

Abstract: A power tool having a cylindrical housing accomodating a hammer and a two-step defining piston head, with central, rear and supplementary chambers in the housing, said head and supplementary chambers being constantly intercommunicated through a passage provided in the housing. The design of the power tool is aimed at minimizing vibrations of the housing and reduction of the forces applied to the handle during normal operation of the power tool.

Abstract: The nozzle is provided with a bar which may be rotated to and fixed at various angular positions. The bar has a longitudinally extensive cut away portion, providing a fuel passage. Varying the angular position changes the turning velocity of the vortex-type jet issuing from the passage. The effect of varying the shape of the fuel passage is also described. The purpose of variation is to cause fuel to be properly retained on the saucer shaped top surface of the impact block until the piston strikes the surface, causing the fuel to atomize and be uniformly dispersed to enhance complete combustion of the fuel.

Abstract: The device features its housing carrying the soil sampling ing socket and the striker arranged coaxially to said socket, and adapted to act thereupon and establish some chambers in said housing, which are alternatively communicated, through the inlet fitting and the piping connected thereto, with a source of compressed air for the striker to perform forward and return strokes. The piping portion immersed in water is essentially a rigid pipe joined with the inlet fitting by way of an axially spring-loaded sleeve whose one end is rigidly connected to said pipe. Arranged along said pipe is another pipe rigidly coupled thereto and serving for used-up gas to discharge from said chambers to the water surface.Such a device is applicable for soil sampling at depths amounting to several scores of meters.