Abstract: Pressure fluid operated impact mechanism having a reciprocating working member (5), a stop member (17) and, formed between said members, a drive chamber (18) with seals (15, 16) and a regulating valve (21) co-operating with a supply opening (25) for pressure fluid, in which opening a sleeve (24) can be arranged for the journalling of the valve. The valve blocks the opening when the working member (5) and the stop member (17) have moved a distance away from each other and is open when they are close to each other. Through the valve and the working member, a discharge channel (33, 31, 20, 32) for pressure fluid is provided which is closed when its inlet opening (33) is inside the stop member and is freed when the working and stop members have moved a distance away from each other.

Abstract: An isolator for use in a hand-held vibrating device for providing optimum vibration isolation by utilizing elastomeric sections. Six embodiments are shown which utilize elastomer sections to enhance vibration isolation along an axial direction of vibration. A first embodiment includes a frustoconical section, while the second employs a W-shaped buckling element. A third embodiment includes use of a tuned fluid inertia which is tuned to substantially coincide with a predominant operating frequency of the vibrating device and produces forces to substantially reduce the vibration transmission, while three other embodiments employ metallic buckling springs. Another embodiment employs a tuned vibration absorber and still another combines a tuned mass with a buckling column.

Abstract: A pneumatically operated fastener drive device that comprises a housing assembly including a nose assembly defining a fastener drive track. A cylinder is disposed in the housing assembly, and a resilient bumper is disposed towards a bottom of the cylinder. A drive piston is slidably and sealingly mounted in the cylinder for movement through an operative cycle. The drive piston engages the bumper at the end of the drive stroke. A fastener driving element is operatively connected to the piston for movement therewith and extends through an opening in the bumper. A valve arrangement is movable between a closed position and an opened position to effect movement of the piston and fastener driving element. An actuator and trigger member are operable to control the valve arrangement. The bumper has a sealing portion surrounding the opening in the bumper and disposed outwardly from the cylinder. The sealing portion has exterior surfaces disposed in engagement with adjacent surrounding surfaces of the nose assembly.

Abstract: An air pressure actuated shovel for removing shingles and attached nails from a roof to facilitate re-roofing. The shovel has an elongated handle with a finger actuated trigger mechanism attached to its top end and a shovel blade supporting an air hammer attached to its bottom. The trigger connects the air hammer and an external pneumatic power source via an air hose inside the handle so that when the trigger mechanism is squeezed, a reciprocating piston, driven by an air hammer, abuts the shovel blade to cause it to vibrate. The vibrating shovel blade effectively loosens shingles and nails from the roof of a building. The removal of shingles with the associated nails intact enhances safety due to the elimination of flying nails.

Abstract: A high-pressure gas operated setting tool including a piston guide (7), a driving piston (21) axially displaceable in the piston guide (7) and formed of a head (9) and a stem (8), and a deformable member surrounding the stem (8) and extending between a stop (17), provided in a front, in the setting direction, end portion of the piston guide (7) and a front, in the setting direction end surface of the head (9), the deformable member (11) having a substantially closed cellular structure.

Abstract: The present invention relates to a buffer mechanism of a hydraulic impact apparatus of a rock drill, and the like, and the buffer mechanism reduces damage by buffering the reflected energy from a shank rod (2), and enables to apply impact by advancing a bit so as to contact the rock even when a rock drill main body (1) cannot advance to a predetermined position for lack of thrust before the next application of impact after the rock drill main body once retracted, thereby to improve the efficiency of impact application. In a rock drill including an impact mechanism for applying impact to the shank rod (2), and a chuck driver bush (13) for transmitting thrust to the shank rod (2) to be applied to an object to be crushed, a front damping piston (4) having thrust smaller than thrust of the rock drill main body (1), and a rear damping piston (5) having thrust larger than the thrust of the rock drill main body (1) are provided at the rear of the chuck driver bush (13).

Abstract: A pneumatic tool is disclosed which includes vibration mounts to reduce the amount of vibration transferred to the user. The vibration mounts include a pair of support members and at least one resilient vibration isolator connecting the support member in a spaced relationship. A compressed air conduit passes through the support member openings but is only directly fastened to one of the support members.

Abstract: A hydraulic breaking hammer having a machine housing including a cylinder bore and an impact piston which is reciprocatingly movable in the cylinder bore in response to an alternating hydraulic pressure, and a tool part having: (i) a head portion fitted to a front portion of the machine housing, and (ii) a guide bore which lies in line with the cylinder bore and in which a breaking tool is slidably carried and repeatedly subjected to impact by the impact piston. A seal is arranged at the front portion of the machine housing between the cylinder bore and the impact piston for separating drive hydraulics of the breaking hammer from the tool part, and a transverse slot is formed in the front portion of the machine housing between mutually opposing side wall portions of the machine housing so as to intersect the cylinder bore forwardly of the seal.

Abstract: The present invention realizes effective recoil reduction and idling strike prevention with a minimum constitution. In a tool holder (6), a thermal-resistant O-ring (22) is arranged between two steel washers (21,23) near the joint to the barrel (5). The O-ring (22) has a cross-sectional diameter of approximately 7 mm. The inner diameter of the O-ring (22) is made slightly greater than the diameter of a cylindrical portion (19b) formed at the rear of an intermediate element (19) and slightly smaller than the diameter of a flange (19a) formed at the rear of the cylindrical portion (19b). Likewise, the inner diameter is made slightly greater than the diameter of a recess (18b) of a striking member (18) formed in front thereof and slightly smaller than the diameter of a flange (18a) formed in front of the recess (18b).

Abstract: A moling apparatus comprises a housing having a head for penetrating ground, an anvil in the housing connected to the head, and a hammer in the housing and spaced therefrom by a spring. A vibrator unit is spaced from the hammer and arranged to transfer vibration to the housing and the hammer. In a first mode of the apparatus, vibration transmitted to the housing causes fluidization of the surrounding ground to allow progressive penetration of the apparatus. In a second mode, the braking effect of the ground on the head causes the hammer to move against the spring and impact the anvil thereby driving the head through the ground, the apparatus being operable at or between each mode.

Abstract: An isolator for use in a hand-held vibrating device for providing optimum vibration isolation by utilizing elastomeric buckling sections which operate in a buckled mode during normal use. The buckled elastomer sections significantly reduce the spring rate within an operating load range thus substantially reducing the vibration transmitted to the user. Six embodiments are shown which utilize buckling sections to enhance vibration isolation along an axial direction of vibration. A first embodiment includes a frustoconical section, while the second employs a W-shaped buckling element. A third embodiment includes use of a tuned fluid inertia which is tuned to substantially coincide with a predominant operating frequency of the vibrating device and produces amplified counter inertial forces to substantially reduce the vibration transmitted to the user, while three other embodiments employ metallic buckling springs.

Abstract: A vibration-reduced impact tool is disclosed wherein an elastomeric vibration isolator is fixedly attached within the tool housing and functions to absorb the vibration typically transmitted from the handle to the operator. The isolator is mounted between the cylinder assembly and the handle. As the tool is operated, a piston within the cylinder assembly is driven forward where it impacts with a tool accessory. The impact causes the piston and cylinder assembly to slide rearward in the tool housing, toward the handle. The elastomeric isolator absorbs the rearward movement of the cylinder assembly and thereby eliminates much of the vibration normally transmitted from the cylinder assembly to the handle and in turn, to the operator.

Abstract: A pneumatic hammer comprises a rigid unit of construction, which comprises a housing, a handle, an operating cylinder resiliently supported in the housing, and a tool holder for receiving a tool movable in a striking direction by the operating cylinder. The operating cylinder is axially movable in the housing relative to the tool holder. Compressed air is supplied to the operating cylinder, and a damping spring acts upon the tool holder in a direction opposite to the striking direction.

Abstract: Disclosed is a vibration isolator which is comprised of parallel flexible beams of rectangular cross sections connected between parallel mounting plates to permit parallel translation of the mounting plates in substantially one parallel direction only thereby permitting the vibration absorber to absorb relative induced motion or vibration in one preferred direction only while retaining relative stiffness for control in the remaining two coordinate directions as well as restraining torsional twist.

Abstract: In a power hand tool, especially a screwdriver, with a motor, a planet gear and a rotary impulse generator, a spring mechanism is provided to damp vibrations of the housing caused by the rotary impulse generator. To improve the damping with a simple design, one end of a compression spring is supported on a ring, which in turn is guided at a coil which is parallel to the axis, on the one hand, and is guided displaceably in parallel to the axis between a part rigidly connected to the housing and a part exposed to the rotary impact, on the other hand. The other end of the compression spring is supported on a part rigidly connected to the housing.

Abstract: This invention relates to an attachment device for a pneumatic hammer tool used to remove a bolt or rod being held in a fixture. The low cost attachment device consists of an alignment sleeve and a tapered coil spring which aligns a driving bit of an air hammer to the bolt to be driven from the fixture and absorbs the shock of the impact during the driving operation. As the driving bit reaches the end of its travel, the addition of a spacer bar allows the driving operation to continue. A method for removal of the bolt is disclosed to facilitate the removal operation. This method relies on the contact of the alignment sleeve with the fixture and the compression of the spring to facilitate quick removal of the bolt. An application of this apparatus has been used to remove a spring attachment bolt on a truck trailer reducing the time for removal to 30 minutes from 3 to 4 hours.

Abstract: Vibration and noise are considerably reduced in a pneumatic impact tool by structure generating a novel vibration dampening action during tool operation. Dampening chamber members in the tool undergo compression when the reciprocating work member recoils as a method for such attenuation. Resilient seal members are further included in the tool construction to assist with the vibration dampening effect. Inclusion of oppositely biased spring members in the tool construction still further reduces the vibration attenuation.

Abstract: A tool for driving a nail or other fastener is actuated by a caseless propellant charge formed of combustible material that is transported into a combustion chamber on a strip. The propellant charge is ignited by striking a sensitizer portion of the charge at an oblique angle. The ignition member intermixes the sensitizer material with an oxidizer layer of the surface of the propellant charge, resulting in combustion of the charge. When ignited, the propellant charge is compressingly interposed between an orifice plate and a movable portion of the combustion chamber. The orifice plate includes a pedestal with an annular compression surface that separates the surface of the ignition area from the remaining surfaces of the charge, insuring that ignition gases are forced through the charge. An annular C-shaped ring is interposed between the orifice plate and the movable portion of the combustion chamber.

Abstract: A device removably attaches to a skid steer and is used for breaking up asphalt, concrete, etc. A hollow rod is suspended from the device, and a nipple provides liquid communication to the interior rod chamber of the hollow rod. A head is provided on a lower end of the rod and a cylinder is movably provided around the rod's lower end so that upper and lower cylinder chambers are formed within the cylinder, above and below the head. Perforations provided in the lower end of the rod provide liquid communication between the rod chamber and the upper cylinder chamber. The lower cylinder chamber is charged with gas. A weight and a breaking tool attach to the bottom end of the cylinder and move upward and downward in conjunction therewith. A switch provided on the frame is tripped as the weight is raised, thus sending an electrical impulse to a timer, causing it to momentarily supply electricity to dump and directional valves, simultaneously closing them.

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: A percussion hammer tool comprises a spindle 1 causing rotation about an axis thereof. The spindle 1 is driven by a motor M. A hammer 3, slidably coupled with the spindle 1, generates a percussion force to rotate and hit an anvil. The anvil is divided into an engaging portion 7 engageable with the hammer 3 and a tip tool holding portion 8 holding a tip tool 16. The engaging portion 7 and the tip tool holding portion 8 are locked with each other. A torque transmitting mechanism 11 makes the engaging portion 7 and the tip tool holding portion 8 displaceable with each other telescopically in an axial direction. A cushion member 10 is provided in a clearance 9a between the engaging portion 7 and the tip tool holding portion 8, thereby transmitting an angular component of the percussion force while absorbing an axial component of the percussion force. An additional cushion member 13 may be interposed between the spindle 1 and the anvil.

Abstract: Vibration and noise are considerably reduced in a pneumatic impact tool with structure providing novel vibration dampening and vibration isolation. The required vibration reducing components employ particular vibration dampening chamber members which dynamically interact with further included multi-part spring and elastomeric members.

Abstract: A percussion boring machine having an impact piston axially movable in a housing, a control pipe connected to a compressed air hose and an elastic separator fitted between the housing and the control pipe and held under axial compression, whereby assembly of the separator is simplified. In addition the housing, control pipe and compressed air hose suffer less damage, and the control pipe can be assembled and disassembled more easily.

Abstract: A rapping hammer system adapted for periodically rapping and cleaning tubes of a heat exchanger unit to remove undesired deposits from outside the tubes. A plurality of rapping hammers are each pivotably attached to a radial arm extending outwardly from and spaced apart along a rotatable shaft. A spring device is attached to each radial arm and arranged to contact the rapping hammer with sufficient force so as to substantially restrain repeated striking movements of the rapping hammer against an impact stem of the heat exchange unit following an initial impact of the hammer. A method is also disclosed for operating the rapping hammer system for periodically rapping and cleaning the outside surface of heat exchanger tubes such as boiler tubes of accumulated ash and soot deposits.

Abstract: The present invention relates to a sealing device for the driver member of a pneumatically operated driving tool for fasteners. It comprises a working cylinder, a working piston slidably arranged in said working cylinder for movement between an upper and a lower dead center, a resilient stop member defining the lower dead center of the working piston movement, a driving member secured to said working piston and extending through an opening of said stop member, a control valve actuated by a trigger to alternatively connect a cylinder space above said working piston with a source of compressed air and to atmosphere, and a piston return space in communication with a cylinder space below said working piston.

Abstract: A handheld paving breaker includes a reciprocal chuck in a front head and an elastic spring for biasing the chuck toward the fronthead. The chuck can move longitudinally, but is restrained from rotation in the fronthead. A moil mounted in the chuck is biased against the work surface by the chuck, to provide better control of the moil, during start-up and operation. Wear pads between the spring and members against which the spring is seated improve spring life.

Abstract: The impact tool is provided with a piston (15) oscillating within a cylinder (10). For selecting, with which piston impact surface the piston (15) impacts on the head (7) of a tool holder (2) and accordingly for the selection whether the impact tool generates forward or rearward strikes, respectively, the cylinder (10) is displaced pneumatically between two positions. The displacement occurs depending on the position of a switch (21). This changing of the impact direction is simple and makes it possible to fix the tool holder in the housing (1) making the impact tool sturdy.

Abstract: The present invention is for a holder for a device comprising axially vibrating and/or beating tools, e.g. a device for removal of hard layers by axing using an axially vibrating and beating chisel. The device is manually controlled and transfer of vibrations and beats from the chisel to the handles is eliminated or much reduced by shock absorbers which are arranged parallel to the chisel. The chisel and its power machine are mounted onto the holder by a shaft which is connected to the lower ends of the shock absorbers. The device also comprises a backward support so that in operation it does not need to be held in position but only directed.

Abstract: A pneumatic tool is disclosed which includes vibration mounts to reduce the vibration transferred to the user. The vibration mounts include a plurality of support members and at least one resilient vibration isolator connecting the support member in a spaced relationship. A compressed air conduit passes through the support member openings and includes at least one seal disposed between said support members and the air conduit.

Abstract: A railroad spike driving tool (30) is adapted to be inserted by its shank (22') for cooperation into hand-held hammer machines of the type comprising a machine housing (10) with a cylinder (11), in which a reciprocating drive piston (14) via a gas cushion in a working chamber (12) repeatedly drives a hammer piston (15) to impact on the shank (22') during spike driving. Forward sudden displacement of the shank (22') causes the hammer piston (15) to perform a forward blow in the void and come to rest. If the tool (30), as a result of the last impact and simultaneous sideward shifting of the machine, happens to hit against the rail, a safety spring (36), pre-stressed between a rearwardly facing shoulder (34) on the tool (30) and the machine housing (10), prevents the tool (30) from bouncing back into the machine and thus from being hit by said hammer blow in the void or from releasing a new blow. Possible injury to the operator is thereby avoided.

Abstract: A fastener driving tool prevents the tool from twice striking, so-called double-driving in a single driving operation. A portion closing the lower end of a cylinder of the tool is formed with an annular recess to receive a ring bumper as a shock absorber of a piston. The recess has a sufficient depth to move a lower portion of the bumper downward and upward. The bumper is fittingly pressed into the recess to form an air chamber in the recess closed by the lower end of the bumper. A check valve is positioned between the air chamber and a supply of the pressurized air to feed the pressurized air to the air chamber so that the pressurized air is further compressed by the bumper which is downwardly moved by the abrupt downward movement of the piston. Thus, greater reaction force is applied from the air chamber to the lower portion of the bumper so as to prevent a driver of the tool from the double-driving.

Abstract: A handheld paving breaker includes a reciprocal chuck in a front head and an elastic spring for biasing the chuck toward the fronthead. The chuck can move longitudinally, but is restrained from rotation in the fronthead. A moil mounted in the chuck is biased against the work surface by the chuck, to provide better control of the moil, during start-up and operation. Wear pads between the spring and members against which the spring is seated improve spring life.

Abstract: A hammer of the type having an impact tool driven by pressurized fluid has a hammer body portion with a closed rearward end and an open forward end and a piston longitudinally movably housed within the hammer body portion for striking a tool mounted at the open forward end of the hammer body portion, to thereby impact an object with the tool. The hammer has a fluid valve housed within the closed rearward end of the hammer body portion rearwardly of the piston and in communication with a source of high pressure fluid for driving the piston. The fluid valve has a valve body portion defining an interior chamber and a continuous exterior side wall, and a longitudinal opening in communication with the interior chamber. The valve body has a first body portion and second body portion which is identical to the first body portion and positioned longitudinally in relation thereto within the closed rearward end of the hammer body portion.

Abstract: A damping device is constituted by a substantially cylindrical damper body (1) with an axial through bore (6), where the bore (6) accomodates a central pipe (3) which e.g. can lead a cooling liquid. The central pipe (3) is connected rigidly to or into the machine element to be damped, preferably in a cylindrical and axial cavity in a boring bar (9). Ring-shaped, elastic spring elements (2) placed in the ends of the damper body (1) and between the central pipe (3) and the damper body (1), as well as damping oil (4) in the clearance between the central pipe (3) and the damper body (1) transform motion energy into heat and provide the damping action. The stiffness of the spring elements (2) can optionally be adjusted.

Abstract: Vibration and noise are considerably reduced in a pneumatic impact tool employing a reciprocating work member such as a chisel or hammer by providing composite elastomeric attenuation element in the tool construction. A laminar configuration of the attenuation elements is employed having dual outer layers of elastomeric material in combination with a rigid inner layer and with such attenuation elements being located in the tool construction for physical impact by the work member.

Abstract: A hydraulic ram assembly is provided to be used, singly or in multiples, in raising a weighted member, such as a hammer (30) for pile driving, each having means whereby fluid used to extend a respective piston (26) can readily escape to give a sudden release, gravity induced return movement.

Abstract: A hydraulic impact hammer comprises a protective casing, a hydraulically operated piston and a member for guiding the piston, and an impact member and a member for guiding the impact member. The piston-guiding member and the member guiding the impact member are made separate with respect to each other in order to prevent propagation of the tension wave reflected from the impact member. However, the piston-guiding member and the member guiding the impact member are each connected to the protective housing through at least one attenuating element.

Abstract: A reversible impact-operated boring tool and a method for reversing the direction of operation of the same rapidly and safely is disclosed. The tool according to the invention possesses a second supply line for supplying pressurized fluid to the tool. The second supply line provides pressurized fluid to a directional valve within the tool. The tool operates in the forward mode for burrowing into the soil when pressurized fluid is supplied to this directional valve. When the pressurized fluid supply is terminated and the fluid is exhausted from the valve, the tool operates in the reverse mode. The tool according to the invention can be reversed safely without any need for hose manipulation and without turning off the primary fluid supply line.

Abstract: A hydraulic impact hammer comprises a protective casing, a hydraulically operated piston and a member for guiding the piston, and an impact member and a member for guiding the impact member. The piston-guiding member and the member guiding the impact member are made separate with respect to each other in order to prevent propagation of the tension wave reflected from the impact member. However, the piston-guiding member and the member guiding the impact member are each connected to the protective housing through at least one attenuating element.

Abstract: A valveless percussive pneumatic drill includes a housing, a piston in the housing, reciprocating along the axis of the housing, a piston support bearing in the housing and an air distributor in the housing, the air distributor being mounted in the housing for flexible elastic movement therein, to permit slight misalignment of the piston with respect to the axis of the housing.

Abstract: A shock-absorbing member is fixed to top brackets at the end of a boom opposite to the top of an impact tool. A stopper member is secured to one of the bottom of the shock-absorbing member and the top of the impact tool and the other of the same is formed with a guide recess in which the stopper member is vertically slidable. When the tip of the chisel of the impact tool is pressed hard against an object to be crushed, no turning force will be applied to vibration-damping support members which support the impact tool, thereby preventing the support members from breaking.

Abstract: In a hammer-strikable, powder-actuated, fastener-driving tool, a breech block is mounted within a generally tubular body by several resilient shock absorber structures, each including an elastomeric grommet, an eyelet having a tubular portion surrounded by the grommet and an annular portion, a washer interposed between the annular portion and one end of the grommet, and a screw attaching the breech block to the body. The screw shank extends through the grommet. The screw head bears against the washer. The breech block mounts a firing pin, which is biased backwardly to a normal position, and to which a hammer-strikable button is connected. A barrel, mounted upon the body so as to be axially movable with respect thereto, has an elongate slot. A stud mounted upon the body extends through the slot. A washer disposed around the stud is biased against the barrel so as to impart frictional drag to the barrel.

Abstract: A valveless percussive pneumatic drill includes a housing, a piston in the housing, reciprocating along the axis of the housing, a piston support bearing in the housing and an air distributor in the housing, the air distributor being mounted in the housing for flexible elastic movement therein, to permit slight misalignment of the piston with respect to the axis of the housing.

Abstract: An adaptor for attaching a bit to a rotary hammer drill and for attenuating the hammering force from the drill to the bit. The adaptor comprises a tubular body for engagement with the shank of a drill bit, the body having a closed rear end. Means is provided within the body at the closed end for engagement with the rear end of the shank of the drill bit to attenuate the hammering force.

Abstract: A device for removing pins, nails, dowels, rods, and the like from material which includes wood, metal, concrete, and human and animal bone, includes a pneumatically actuated piston producing a reverse impact striking effect which causes extraction of the pin from the material. The device includes a main housing comprising a tool handle, an elongated barrel partially mounted in the tool handle, and a muffler housing fitted on the barrel and abutting the tool handle. A central chamber extends the length of the barrel, and disposed within the central chamber is a shaft which is adapted for linear reciprocal movement therein. An anvil is mounted at the inner end of the shaft and a tool holder is mounted at the opposite end of the shaft. Slidably disposed on the shaft is a piston which is adapted for linear reciprocable movement thereon for forcibly striking the anvil.

Abstract: A piston is oscillating periodically within a cylinder, propelled by compressed air. At at least one of its end positions, the piston generates a stroke that acts on a working tool, e.g. a rasp. The sizes of the piston surfaces acted upon by the compressed air and the capacities at the cylinder volumes limited by the piston are dimensioned such that the impact momentum of the piston at both end positions is essentially the same. In case of a bone rasp working tool this equal momentum of the stroke advancing the rasp into the bone and the stroke loosening the tool by retracting it, leads to an optimum working of the bone and as little stress as possible on the patient.