Abstract: The side load picket driver is loaded from the side instead of from the bottom. The side load star picket driver is closed at the top end and open at the bottom end and has a slot down the full-length on one side of the star picket driver so that the star picket can be loaded from the side instead of the open end. There are two handles, welded to each side of the star picket driver for the operator to grip the driver and pound the star picket into the ground.

Abstract: A hydraulic hammer assembly is provided. The hydraulic hammer assembly includes a housing and a piston is arranged for reciprocating movement along a longitudinal axis within the housing. A head disposed along the longitudinal axis on an end of the housing and defines a chamber for holding a pressurized gas. The hydraulic hammer assembly further includes a locking mechanism to lock the head on the housing. The locking mechanism includes at least one first flange extending radially from the end of the housing and at least one second flange extending radially from the head, wherein the head is retained on the housing by blocking axial movement of the second flange against the first flange when in a locked position.

Abstract: A system for tracking a harvested agricultural product unit includes a magazine configured to be disposed on an agricultural implement and to facilitate insertion of one or more stakes into the harvested agricultural product unit. The magazine is also configured to store the one or more stakes having a radio frequency identification (RFID) tag. The RFID tag is configured to identify the harvested agricultural product unit and to associate the harvested agricultural product unit with harvesting data. Further, the system includes an insertion device configured to insert one of the stakes from the magazine into the harvested agricultural product unit.

Abstract: A drill bit for percussion rock drilling. An impact portion includes an impact surface for striking against rock in an impact direction. An engagement portion includes a holder configured to hold the drill bit axially in a drill head of a drill string, and a rotation engagement member configured to connect the drill bit with the drill head for rotating the drill bit. An anvil surface is directed opposite to the impact direction for receiving shock waves from a striker rod of the drill string. A flushing channel is configured to transfer flushing fluid to the impact surface. The holder and the anvil surface are inside a holder recess having an opening that is directed opposite to the impact direction. Also a drill string component, a system and a method.

Abstract: An attachment for a fluid-operated percussion drill tool, the drill tool having a backhead assembly for attachment to a drill rod. The attachment comprises a shaft attachable to the backhead assembly, wherein the shaft comprises a central bore in fluid communication with a pressure bore of the drill rod. The attachment further comprises a sleeve co-axially slidably mounted on the shaft, the sleeve comprising an outer shoulder at a rear end thereof, and at least one rearwardly-directed exhaust passage. Pressurised air supplied from the central bore of the shaft to urge the sleeve rearwards into a closed position in which air is prevented from exhausting through the exhaust passage. When a restriction is encountered at the shoulder, the sleeve moves forward to an open position in which air is permitted to exhaust through the exhaust passage adjacent to the restriction.

Abstract: A pneumatic tool percussion hammer features motion ends of the percussion block of the percussion hammer with added configuration of a mass increasing part. The mass increasing part can help to increase the mass of the motion ends of the percussion block without increasing the overall size of the percussion block. Hence, the present invention can effectively increase the inertia force of the percussion block in motion, and consequently the torsion and instant acceleration of the percussion hammer, without the need to increase the overall size of the percussion hammer.

Abstract: A pile driver provided with a housing and at least one body connected with the housing so as to be moved back and forth over a predetermined path, the pile driver being further provided with a drive for moving the body back and forth over the path for the purpose of pile-driving, the pile driver comprising at least two parts movable relative to each other, respectively having at least a first type of sliding surface and at least a second type of sliding surface which during pile-driving slide along each other and between which there is a lubricant, wherein the first type of sliding surface is provided with polyether ether ketone.

Abstract: A post driver for driving hollow posts, especially plastic posts, has an elongated central guide shaft and a hollow outer sleeve. The guide shaft has a length and diameter sized to pass fairly freely through but generally fill the post's hollow core to protect against the post buckling during pounding strokes. The outer sleeve annularly surrounds a substantial upper portion of the post for similar reasons. The outer sleeve transmits pounding strikes to a stop formation that rests stationary on the post's top end. That way, a user manually applying pounding strokes to the stop formation's upper surface transmits force to not only the post's top end but also the guide shaft's bottom end. Optionally, the guide shaft's bottom end is tipped and sticks out a little in order to pierce a pilot hole in the ground, and clear a path, for the post to follow.

Abstract: According to the present invention, there is provided a jackhammer trolley comprising a mainframe member with a clamp member at the bottom end and an extension bracket portion at the top end, a base frame member removably attached to the mainframe member by pivoting joints with at least one wheel member removably attached to its bottom, a handle member having a hand lever attached to said top end, and at least one vibration dampener fixed to said top or bottom end of the mainframe member.

Abstract: A striking-mechanism body of a handheld power tool at least a first part of the striking-mechanism body, having an impact surface and/or a lateral surface of a first material, and a second part of the striking-mechanism body of a second material, and the first material being more resistant than the second material in terms of at least one material characteristic, the striking-mechanism body being configured as a one-piece steel body so that the first material and the second material are the same, and the first material of the first part body undergoes a heat treatment that differs from that of the second material of the second part of the striking-mechanism body, or the first and the second materials are different, and the first and the second parts are joined together.

Abstract: A tool body (1) has a coupler for engagement with any of a variety of tool heads such as a spade head (3), and a hatchet head (4). A tool comprising the body (1) and a tool head (3-10) is a hammer action tool. It may be used as a fork, spade, chisel, hatchet, or any tool which would benefit from a hammer action. A tubular shank (21) and a hammer (22) are together a hammer weight which is pushed down by the user until it hits a receiver (23), driving the tool head. A spring (24) returns the hammer (22) and a shank (21) back up to the start position ready for the next hammer action. It also acts to push the tool head out against a work surface for overhead work such as chiseling. A spring (25), acting between a hammer impact part (22) and the handle (21, 27) takes the shock out of the impact for the user's hands. The shank (21) and the hammer (22) slide up and down together on the box-section receiver tube (32).

Abstract: A packable battering ram quickly disassembled for transport by two or more persons. In the preferred embodiment, the invention has first and second body members that are symmetrical, but otherwise identically shaped and sized. When assembled, the first and second body members form a lower surface that has a concave portion that approximates the natural curvature of the back of an adult male. The packable battering may be disassembled to distribute the weight between multiple people, yet quickly assembled for use upon arrival at a emergency response location.

Abstract: A silicon lump crushing tool comprising a pneumatic piston drive means for driving a piston installed in a casing from a retreat position to a projection position by air pressure, a guide tube connected to the casing and extending in the movement direction of the piston, and a hammer head. The rear end portion of the hammer head is movably inserted into the front end portion of the guide tube, and when the piston is driven from the retreat position to the projection position, the front end of the piston collides with the rear end of the hammer head.

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, and a piston slideably mounted within the housing. A drive mechanism converts rotary output of the motor into a reciprocating motion of the piston. A ram is slideably mounted within the housing, forward of the piston, and 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. A vibration dampener is coupled to the housing and is configured to remove metal splinters from lubricating fluid in the housing while counteracting vibration generated by movement of at least one of the piston, the ram, and the beat piece.

Abstract: A method for operating a driving tool that can be employed for driving fasteners, such as nails.

Abstract: A pneumatic wrench includes a pneumatic motor, a striking portion, and a drive shaft. The striking portion includes a support seat, a first pin, a second pin, a first hammer, and a second hammer. Thus, the locking strip of the first hammer and the locking strip of the second hammer increase the thickness of the first hammer and the second hammer respectively to reinforce the structural strength of the first hammer and the second hammer, thereby preventing the first hammer and the second hammer from being broken due to vibration so as to increase the lifetime of the first hammer and the second hammer.

Abstract: A method and apparatus providing a sign post assembly including a stabilizing post member, an outer tubular post and a horizontal post member. The stabilizing post member includes a spike portion and an inner post portion with a blocking portion coupled to the post member above the spike portion. The outer tubular post defines a post bore substantially extending through a length of the outer tubular post with at least a lower open end. The outer tubular post is configured to mate with the inner post portion to substantially extend within the post bore of the outer tubular post. The horizontal post member includes a horizontal post portion and a post coupling portion. The post coupling portion is configured to operatively couple with the inner post portion of the stabilizing post member so that the horizontal post portion extends transverse to the stabilizing post member to hang a sign thereto.

Abstract: A percussion piston for use in a drilling apparatus includes a drill bit and at least three tubular parts which increase in diameter in a direction extending from the drill bit toward a rear end of the piston. The piston further includes flanges positioned between the tubular parts and a first corresponding delivery space at the rear end of the piston. At least two additional corresponding delivery spaces are positioned between the first corresponding delivery space and the drill bit. Channels allow the transport of pressurized hydraulic fluid to and from the first and additional corresponding delivery spaces such that an energy pulse produced by impact of the piston on the drill bit is almost completely absorbed by the drilled object.

Abstract: The present invention relates to a hammer device, preferably a down-the-hole hammer, including a drill bit (11) and a piston (10) reciprocating therebehind to periodically strike the drill bit. The drill bit (11) includes front (11a) and rear (11b) portions of different impedance, and the piston (10) includes front (10b) and rear (10a) portions of different impedance. In the drill bit, the front portion (11a) has a larger impedance than the rear portion (11b). In the piston, the rear portion (10a) has a larger impedance than the front portion (10b). The length of the drill bit front portion (11a) is about twice the length of the drill bit rear portion (11b). The length of the piston rear portion (10a) is about twice the length of the piston front portion (11b). The invention further relates to a drill bit (11) and a piston (10), per se.

Abstract: An hydraulically driven percussive hammer for use with down-the-hole percussive hammer drilling, the hammer having a piston and liner combination which provides for multiple stages where there are successive effective piston drive areas of diminishing size for both return and impact directions which minimizes peak pressures from hydraulic hammer effects.

Abstract: An improved pile driving drop hammer of the free piston internal combustion engine type preferably has integral pistons on each end of a ram that reciprocates, usually vertically, in an enclosing bore. There is a combustion chamber on each end of the bore and exhaust ports situated near each combustion chamber such that the ports are opened, two cycle engine fashion, by the associated piston, after some movement of the piston, after combustion takes place to vent the active combustion chamber and then serve as intake ports when the piston moves some distance farther along the bore. At each end of the bore an anvil extends from the bore, axially movable some amount, to serve as an end to each combustion chamber. The lower anvil delivers ram impact energy to the driven piling and the upper anvil delivers impact energy from the ram to a free rising mass that is the essential element of this invention as an improvement to existing hammer designs.

Abstract: A device for making holes in the ground, such as for a golf course, has a tubular cutter having an open first end for insertion into the ground, and an opposite second end from which a guide extends. A percussion weight is guided for movement along the guide and exerts a hammering force on the second end of the cutter. A tubular part is connected to the end of the percussion weight that lies distal from the tubular cutter. The tubular part guides the percussion weight axially along the guide. A handle for maneuvering of the percussion weight is attached to the top of the tubular part. The cutter and associated guide on the one hand, and the percussion weight with associated tubular part carrying the handle on the other hand, can be locked together releasably against axial movement, are non-rotatable, and are also releasably locked against rotation movement, so that the cutter can be easily removed from the ground once the hole is cut.

Abstract: A device for removing runners from intermediate molded products includes a holding assembly for maintaining the products in a desired position, a hammer member, an assembly for vibrating the hammer member to cause repeated striking of the intermediate product so as to separate runner and product portions thereof and a control arrangement for selectively activating and deactivating the vibrating assembly. The control arrangement provides for positioning the vibrating assembly in at least one predetermined position upon deactivation thereof so as to enable the vibrating assembly to be readily restarted. The holding assembly can incorporate a robot arm for transporting and positioning the intermediate molded product for runner removal. In order to protect the robot arm from the effects of vibrational forces, the intermediate molded product is adapted to be resiliently attached to the robot arm.

Abstract: A grounding rod or other article is manually driven into the ground by an impact tool including an elongated guide shaft or rod having a center axis and upper and lower end portions. The lower end portion of the rod is secured by a cross pin to a coupler including a cylindrical body of electrical insulating material. The body defines a cavity extending downwardly from a metal anvil pad embedded within the body, and the cavity is formed by angularly related wedge surfaces extending from a slot. The slot opposes a threaded fastener extending radially through a flanged nut also embedded within the body. A cylindrical metal weight or hammer is slidable on the guide rod for impacting the coupler, and the hammer carries a pair of freely rotatable knobs disposed circumferentially at an angle less than 180.degree..

Abstract: A hydraulically operated mole has a reciprocating hammer operated by means of an impact mechanism which may be readjusted from forward to backward wiring by displacement of a valve tube secured to a piston near the rear end of the apparatus. The piston is activated by the switching of oil supply and withdrawal respectively to the tank between two pipeline stubs at the rear end of the apparatus. The fluid connections between the stubs and the piston are completely separated as regards the flow. As a result, complicated and vulnerable valve elements used in known hydraulic moles are avoided.

Abstract: The weight of a pneumatic ground piercing tool of the type having a stepped air inlet is reduced and tool power increased by providing the tool body with a dual diameter. The tubular tool body has a front section and a rear section which has a greater inner and outer diameter than the front section, thereby reducing overall tool weight. In a preferred embodiment, the rear end portion of the striker likewise has a greater outer diameter than the front end portion thereof. The bearing of the front end portion of the striker remains in sliding contact with the interior of the front body section during tool operation, and the bearing of the rear end portion of the striker likewise remains in sliding contact with the interior of the rear body section. In this manner, the power of the tool is enhanced because the tool has less weight and the air distributing mechanism, located in the rear body section, is the same size as in a conventional tool wherein the entire body has a uniform diameter.

Abstract: A pole driver 10 has a platform 12 on wheels 14 and 16 with leveling lift jacks 18 to assure horizontal orientation of the platform. A hammer drive assembly 24 is pivotally mounted on the platform 12 between a horizontal travel position and a vertical operating position. The hammer drive assembly includes a channel guide 34 and slide rail 36 with a weight 78 attached at a bottom end thereof. An operating handle 46 is mounted on the bottom section of the channel guide 34. A pair of brackets 66 are mounted under the slide rail assembly 24 to vertically orient a pole 74 under the weight 78 to be pounded into the soil by the slide rail 36 and weight 78.

Abstract: Three tubular elements are rigidly bundled together so as to have, in use, a common upper end elevation. The first element is closed at its upper end by a rigid cap element and depnds from the common upper end by approximately 30 centimeters (approximately two feet). The second element consists of a substantially identical length of tube, open at its upper end, depending to a plug element closing its lower end, from which another identical length of tube coaxially depends to an open lower end at about 62 centimeters (marginally greater than four feet) below the upper end. The third element depends from the common upper end through a distance preferred to be between one hundred fifty two centimeters and one hundred eighty three centimeters (between approximately five and six feet), for use as a handle.

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 post driver for driving a wedged anchor into the ground wherein said wedged anchor is adapted to receive a post at the top end thereof comprising: an elongated inner shaft having a rectangular cross-section, said inner shaft having one end of which is adapted to be received by said wedged anchor; a plate co-extensive with said rectangular cross-section and fixedly secured at said one end of said elongated inner shaft; a hollow elongated outer shaft having spaced first and second open ends; said first open end of the hollow elongated outer shaft adapted to receive another end of the inner shaft for relative slidable movement therebetween; a mass presented at the second open end; aligned apertures presented by the mass and the outer shaft for receiving one end of a handle to retain the mass and the outer shaft together.

Abstract: A stake driver having a first rod that has at least one solid end for driving a stake. The other end may be pointed. A second larger diameter rod is slidably insertable over the first rod. One of the open ends of the second rod is located over a stake. Then the first rod is moved upward to allow the stake to be encircled by the open end of the second rod. The end of the second rod may be slotted to accomodate a rectangular stake or marker fastened to the top of the stake. With one hand grasping the second rod, the other hand lifts the first rod and then releases it so that the first rod can free fall and drive the stake into the soil. If additional force is required to drive the pointed end of the first rod into the soil, a third rod is slid onto the second rod and screwably connected to it.

Abstract: An angular attachment to a rotary and percussive power machine, such as a hammer drill, includes a rotary power input tubular member driven by a rotary part of the power machine, a tubular power output supported for rotation at an angle relative to the axis of rotation of the power input member and including a holder for a rotary and percussive work tool. The tubular power input and output members are interconnected by an intermediate power transmission. A device for transmitting impacts from the percussive part of the power machine includes two guiding channels arranged in alignment with central bores of the tubular power input and output members and each enclosing at least one impact deviating element. The impact deviating elements are in sliding engagement with each other and with a corresponding coupling member arranged in respective contact bores of the power input and output members.

Abstract: A tool for driving metallic fasteners which includes a magnetic driving head defined by partially separated segments of opposite polarity which are spaced from one another along a portion of their width, but which are integrally connected by an integrally formed reinforcing bridge element so that the impacting surface of the tool is generally continuous except for spaced grooves which extend inwardly of the impacting surface of the tool and which partially separate the magnetized segments from one another.

Abstract: Method of controlling impact force and shock interval at a drop hammer of the type which has a core (10) and a number of casings (12, 14, 16, 19) arranged concentrically around the core. Between the core and the casings, spacings are arranged, and the core and the casings are interconnected alternatingly at one end and the other beginning at the upper end of the core. Between the lower end of the core and those ends of one or more casings, which are not permanently connected, a shock wave transferring connection is provided to short-circuit the path of the shock wave through the core and the casings.

Abstract: A pair of rotating flywheels which engage a ram for moving a tool which impacts a part, such as a nail to be driven, are rotated in opposite directions from a single motor or other rotating means, through a pair of substantially identical gears, one of which drives one flywheel and the other of which drives the other flywheel. The drive connection between the respective gears and each of the flywheels may include a belt and pulley arrangement, so that each flywheel may be driven directly by the respective belt but the flywheels are pivoted toward and away from the ram so that when the flywheel moves toward the corresponding side of the ram, the connection between the belt and the corresponding pulley will tend to slacken. A special flywheel pulley has an inner V-shaped groove and parallel side walls for guiding the belt into the groove when full tension occurs.

Abstract: A ram head for self-driven pneumatic ram drills for producing boreholes in the earth, having a generally tubular housing within which there is movable axially back and forth an impact piston whose impact energy can be transmitted to the ram head arranged at the front end of the housing. In order on the one hand, to crush obstacles by high energy and, on the other hand, to avoid too strong a compacting of small particles of earth in front of the apparatus and in addition make it possible to drive pipes, the generally conical ram head is provided with a central axial bore within which an impact bolt is mounted for longitudinal displacement between two end positions which are limited by stops, at the front end position of which supported by a spring the impingement surface of the impact bolt for the impact piston lies within the anvil surface of the ram head and at the rear end position of which the impingement surface projects from the anvil surface in the direction towards the impact piston.

Abstract: A driving pole for a ground rod or the like is provided wherein the ground rod is positioned in the hollow interior and driven into the ground in increments. Vertically spaced cross pins provide incremental stops for engaging the top of the ground rod for driving the rod into the ground as the pole is forced downwardly. The cross pins are preferably mounted on a bracket and spring biased into engagement tending to force the pin into the stop position. After each driving increment, the pole is raised, preferably with a rapid movement, the ground rod moves downwardly relative to the pole and the next lower pin 20 snaps into position for engagement with the top of the rod for driving. The biasing spring is mounted within the U-shaped bracket and a handle is provided for retracting the pins with a latch for holding the pins in the retracted position for insertion of the ground rod.

Abstract: A ram for driving elongated objects into the ground including a piston jacket, an anvil disposed on the object to be driven, a mechanism located within the jacket for directly impacting with the anvil and for reciprocating at least substantially in a direction of driving the elongated object during driving operation wherein the mechanism for impacting further includes a plurality of cup springs arranged in series in the direction of driving the object and which are in contact with one another and wherein a lowermost cup spring directly impacts the anvil during driving operation.

Abstract: When inserting a locking wedge (14) having planar wedge surfaces (16, 17) between an anvil (4; 5) and a hammerhead (1) or an anvil block lining (6) the wedge (14), which is provided with a draw head (18; 22) is drawn in between two mutually converging locking surfaces (9, 7) on the anvil and the hammerhead or the anvil block insert.

Abstract: A ram block for driving piles and the like into the ground has a lead mass (15) which is enclosed in an inner cylinder (10) and in the space between this and an outer cylinder (11). The cylinders are interconnected at the lower end of the ram block where a cap (14) is arranged in the inner cylinder.

Abstract: Provided is a soil gas sampling probe having shaft extensions, a removable hammer and anvil combination to drive the shaft into the ground, a pointed rotation resistant probe tip, and a movable septum holder.

Abstract: An impacting device useful with a pneumatic drive comprises a housing formed with an outer large-diameter bore and an inner small-diameter bore defining an annular shoulder at their juncture. A driving element within the large-diameter bore is limited against movement by the annular shoulder. A plunger movable within both bores is urged by a spring into the large-diameter bore in engagement with the driving element and carries an impacting element, such as a ball, at its opposite end. A air-vent formed through the housing wall is in communication with the first bore at a location so as to be on the inner side of the driving element when the latter is in its initial position, and at the opposite side of the driving element when the latter has been driven by pressurized air pulses to limit against the annular shoulder. Thereafter the plunger continues moving, under its own inertia, to cause the impacting element at the outer end of the plunger to engage the workpiece.

Abstract: An improved drop hammer or slag breaker is disclosed for use with cranes equipped with electromagnets. The breaker combines a working end made of a specially shaped manganese steel body, which is non-magnetic, with a rounded magnetic metal lifting end or head made of high strength wear resistant steel. The extremely tough manganese steel body is secured to the head by wedges forced through head lug openings and adjacent openings in the body portion. Bolted slidable keepers connected to the head retain the wedges tightly in place. The device is particularly useful for breaking up iron or steel furnace slag into smaller pieces and into magnetic and nonmagnetic pieces, the former of which can then be separated and removed by the crane's magnet. Increased wear performance is afforded by the cast manganese steel body. Increased breaking performance is gained by use of the specially shaped body and/or body working end.

Abstract: A peg device for the fixing of posts and stakes in the ground has a rigid member shaped to permit it to be readily driven into the ground and defining a housing which can receive a base portion of the post or stake. A preferred construction has a number of metal plates forming the rigid member, each plate including a bent up edge portion welded to another of the plates, the assembly of plates being positioned so as to define a central sheath bounding the housing. The rigid member may be shaped to permit it to be screwed into the ground. For driving the peg device into the ground, a driving device may be inserted in the housing and pressure exerted on the driving device, for example by repeated operation of a ram which is slidable up and down a rod portion to abut on a stop.

Abstract: In an apparatus for driving a pile or similar object by the stroke of a hammer, the impact of a hammer stroke is transmitted to the pile or similar object through resilient means comprising a precompressed gas in at least two closed chambers, which may intercommunicate, arranged in series.

Abstract: A seismic wave generator constructed of fungible high density elements contained within a flexible envelope is dropped to impact upon the ground and generate seismic waves for seismic investigations. The non-rigid construction minimizes or eliminates bounce or reverberation after impact. Because of the lack of bounce and reverberation, recordings of the seismic waves produced are relatively free of superimposed wave forms otherwise resulting from multiple impacts.

Abstract: A device which includes a ram and a tube, which device can be used for the production of earth holes and poles which are located in these holes and which poles are made of poured or compressed concrete and a process using this device.

Abstract: In the percussion drill rod assembly of the present invention rotary force is transmitted through a tubular member of the assembly while impact force is transmitted through the rod member centrally located in the tubular member. Either of said rod and tubular members is provided with radially extending protrusions which guide said member with respect to the other member while enabling flushing medium to pass between said members.

Abstract: A hydraulic hammer assembly is disclosed which comprises a stationary piston suspended within a tubular frame or casing and a cylinder locked inside a massive ram within the casing. The cylinder forms a differential hydraulic assembly with the piston and moves up and down along the piston. The cylinder is maintained locked to the ram by the pressure of the hydraulic fluid; and the piston, which is formed of two members, is held in assembly by a continuous hydraulic bias with a special hydraulic balancing arrangement which compensates for the pressure switching in the cylinder to which one portion of the piston assembly is exposed.

Abstract: An automatic hydraulic hammer including a frame with suitable mountings to attach the frame to an existing hydraulic feed test boring drill machine. A weighted hammer is reciprocal within the frame through a measured distance and is arranged for substantially frictionless operation. A hydraulic cylinder mounts upon the frame and receives its power from the hydraulic test boring drill machine. A plunger is responsive to function of the hydraulic cylinder and terminates downwardly in an arrow-shaped head which releasably connects to a plurality of pivotally mounted clamps. When the head engages the clamps, the hydraulic cylinder is functioned to raise the plunger and the releasably attached hammer through a known distance. The top of the frame is provided with a plurality of depending fingers which function with the clamps to quickly and positively release the head at the top of the hammer travel.