Abstract: The present invention provides a defect-less and easy to operate power actuated piston tool with automatic piston return, designated for driving fasteners into a base like masonry, concrete, wood or the like. The tool according to the invention is characterized by that on piston shank (11) of piston (1), there is an elastic returning bush (7), situated between piston head (12) and fastener guide (5), said returning bush (7) is a one-piece in shape of bellow, made of elastomeric material, of regularly variable diameter.

Abstract: The invention is based on a hand power tool, in particular a drilling- and/or chipping hammer, having a machine housing (12), a tool guiding element (16; 54), a hammer tube (14; 52), and a safety catch (32)—fixed in the housing in stationary fashion in the axial direction—for a striker (24) that can be driven by means of a drive piston (22) and that is actively joined with a tool (20) situated in a tool guiding element (16; 54). It is proposed that the tool guiding element (16; 54) is designed to be axially displaceable in relation to the machine housing (12).

Abstract: A vibration damper is disposed between two components (2, 3) of a portable handheld work apparatus (4). The vibration damper is held especially between a housing (6), which holds an internal combustion engine (5), and a handle (7) which is fixed on the housing (6) for guiding the work apparatus (4). The vibration damper includes a coil spring (9) and respective attachment elements (11, 12) at the ends (10, 13) of the coil spring. A coupling member (17) is provided to ensure that the work apparatus can be guided notwithstanding a break of a coil spring. The coupling member (17) projects through the coil spring (9) and bridges the axial distance (16) between the attachment elements (11 and 12). The coupling member (17) is connected to each attachment element (11, 12) so that it cannot separate therefrom.

Abstract: A hand held electrically powered hammer comprises a housing, a motor, and a hollow spindle. A piston and a ram are located for reciprocation within the spindle. A casing encloses at least part of the spindle so as to define a chamber between the spindle and the casing. A damping mass is slideably supported by a spacer and is located within the chamber and is connected to the hammer housing via a spring so as to oscillate back and forth along the spindle to minimize the vibration of the hammer housing and also so as to generate air flows within the chamber for facilitating heat transfer from the spindle to the metal casing.

Abstract: A nail stapler includes a gun and a magazine for receiving and supplying staple nails to the gun. The gun includes a shell, a solenoid received in the shell, a puncher received in the shell for movement from an original position to a punching position due to attraction by the solenoid, a pin secured to the puncher and inserted through the solenoid, a spring compressed between a portion of the solenoid and a portion of the puncher, and a security device received in the shell for buffering the puncher when the puncher is pushed from the punching position to the original position by the spring. The security device includes an elastic end for contact with the puncher. The nail elastic end of the security device includes a plurality of elastic elements. The puncher defines a cavity with a wall for contact with the elastic elements. The shell includes two halves each including a retainer formed on an internal face. The security device defines a groove for receiving the retainers of the halves of the shell.

Abstract: A gear assembly for a power tool. The gear assembly includes a gear assembly housing, a ring gear supported by the gear assembly housing, one of the gear assembly housing and the ring gear having an end defining a first bearing race, a planetary gear carrier member supported for rotation relative to the ring gear and defining a second bearing race, the carrier member being drivingly engageable with a tool element to drive the tool element, a plurality of planet gears supported by the carrier member and drivingly connectable to the gear end of the drive shaft of the motor, the plurality of planet gears interacting with a ring gear to rotatably drive the carrier member, and a plurality of bearing members supported between the first bearing race and the second bearing race.

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: A damping apparatus for a reciprocating pneumatic tool mainly includes a cylindrical damper. The damper has a front opening and an enlarged rear end. The front opening is attached to a cylinder of the reciprocating pneumatic tool. A damping segment is formed between the front opening and the enlarged rear end of the damper. A spiral slot is defined longitudinally through the enlarged rear end of the damper. Several slots are defined parallel and transversely in the damping segment of the damper and communicate with the spiral slot. The damping segment has gaps arranged longitudinally by the slots such that the structure has high internal damping to attenuate shock that is caused by return movement of a piston in the cylinder. Consequently, a user holding the pneumatic tool can feel comfortable.

Abstract: A breaking apparatus, which comprises a percussion device (1), and in the extension thereof, a tool (3) to which a percussion piston (2) belonging to a percussion device delivers impacts. In the axial direction, the movement of the tool is limited by a stopper element (15) if the movement of the tool exceeds a predetermined range of movement (B) in the direction of the impact (A). The stopper element (15) is a piece made of elastic material, which is arranged in a space between the tool and a supporting surface (16). During the stopping of the tool, the capacity of the space for the stopper element reduces, whereby the element is subjected to pressing. By the effect of the tool movement, the stopper element thus rotates about its cross-sectional central axis (21) and at the same time changes its cross-sectional shape in the reducing space. The invention further relates to a tool used in the above-described breaking apparatus.

Abstract: A holder for a drive piston (8) of a setting tool, and including a return element (19) having a first end (21) that applies pressure to the drive piston (8), and a second end (22) spaced from the first end (21), and axial and radial stop elements (16-18) fixedly securable in the setting tool and against which the second end (22) of the return element (21) is displaceable and elastically deformed upon displacement of the drive piston (8) in the setting direction (20).

Abstract: A pavement demolition hammer is removably fastened to a loader and includes a mounting plate securable to the loader. A framework is attached to the mounting plate and is provided with a lower spring and an upper spring spaced from the lower spring. A hammer handle has a proximal end pivotally mounted to the framework for swinging movement between the lower spring and the upper spring, and a distal end equipped with a hammer head adapted to engage the pavement. The loader applies a moving force to the mounting plate such that the lower spring is accelerated against the bottom of the handle causing the handle and the hammer head to swing upwardly from a pavement surface to be broken towards the upper spring. The handle and the hammer head return to the pavement surface either by gravity or acceleration from the upper spring against the top of the handle in a manner that the hammer head impacts and demolishes the pavement surface.

Abstract: A piston holder for drive piston (8) of a setting tool and including at least one friction member for applying pressure to a circumferential surface of the drive piston and having an adjusting surface (17, 24) remote from the drive piston (8) and rising toward a rear, in a setting direction of the setting tool, end of the drive piston, and a pressure element (19, 7′) stationary with respect to an axial direction of the drive piston (8) and which is always in a pressure contact with the adjusting surface (17).

Abstract: A spindle (60) for a machine tool comprising a rear spindle portion (62) and a forward spindle portion (64) with each of the rear spindle portion and the forward spindle portion being rotatable about the same axis relative to one another. The inventive spindle includes one or more spring elements (68) extending between the rear spindle portion and the forward spindle portion whereby with the forward spindle portion and the rear spindle portion rotating at a predetermined amount and with the rotation of the forward spindle portion being constrained at that amount, an additional rotation applied to the rear spindle portion results in a deflection of the springs thereby effecting a torque between the forward and the rear spindle portions. The present invention also includes a control method which has as its objective to control the position of, not the torque applied to, one of the spindles, usually the gear member spindle.

Abstract: A piston holder for a drive piston (8) of a setting tool and having a carrier (7) for two expansion legs (22, 23) for frictionally receiving the drive piston (8) therebetween, with the carrier (7) being fixedly secured in the setting tool.

Abstract: A piston holder for a drive piston (8) of a setting tool and including a circumferential groove (15) provided in a stationary, with respect to the setting tool, component of the setting tool and surrounding the drive piston (8), with the circumferential groove (15) becoming shallower in a drive-out direction of the drive piston (8), and an O-shaped helical tension spring (21) located in the circumferential groove (15) and concentrically surrounding the drive piston (8).

Abstract: An apparatus for emplacing fastening elements into a placement base, for the purpose of fastening components. The apparatus includes a working piston, the acceleration and braking range of which, with optimal emplacement depth (31) and minimal piston length can be adapted to different conditions, and for use with mechanical, pyrotechnical, pneumatic, electromagnetic and electrothermal working piston drives.

Abstract: A piston holder for a drive piston (8) of a setting tool and including a braking element self-lockingly supportable on a drive piston body (10), and spring elements (21, 23; 27, 28) for applying different biasing forces to the braking element (17; 24-26) in respective opposite directions corresponding to a direction of displacement of the drive piston (8) for reducing self-locking forces with which the braking element (17; 24-26) is supported on the drive piston body (10).

Abstract: A hand held-type apparatus for fracturing a gate or riser from a casting subsequent to a foundry pouring process. The apparatus operates off of a driven piston assembly, which upon a stroke of such causes a hammer end of the piston assembly to extend from the apparatus and contact the casting, thereby causing the fracturing of the gate or riser from the casting. The apparatus also includes an assembly for decelerating the driven piston assembly upon a stroke of such, as well as an apparatus for isolating the linear motion of the apparatus from the operator thereof.

Abstract: Power drivers are commonly used in production to tighten fasteners such as nuts and bolts. The socket which engages the fastener is normally coupled to the drive shaft of the power driver by a square male end on the drive shaft and a complementary square female connector on the socket. These components are not produced to close tolerances and as a result there is substantial play permitting misalignment of the rotational axes of the drive shaft and the socket and some rotational freedom between the drive shaft and the socket. In accordance with the invention an anti-vibration adaptor is provided comprising a sleeve containing a cylinder of resilient material which surrounds a portion of the drive shaft and a portion of the socket, including the point of coupling, sufficiently closely to minimize misalignment of the rotational axes of the drive shaft and the socket and reduce rotational freedom.

Abstract: This invention relates generally to an impact tool. The present invention provides a vibration isolated impact tool wherein an impact mechanism and a motor assembly are arranged into a cartridge assembly. An elastomeric member resiliently connects the cartridge assembly with a housing. The cartridge assembly is free to move axially and rotationally within the housing. The elastomeric member absorbs axial vibration and torsional vibration, reducing the vibration transmitted to an operator.

Abstract: This invention relates generally to an impact tool. The present invention provides a vibration isolated impact tool wherein an impact mechanism and a motor assembly are arranged into a cartridge assembly. An elastomeric member resiliently connects the cartridge assembly with a housing. The cartridge assembly is free to move axially and rotationally within the housing. The elastomeric member absorbs axial vibration and torsional vibration, reducing the vibration transmitted to an operator.

Abstract: A device for breaking rocks comprising a substantially vertical guide column which houses a weight for delivering an impact to a tool held within a cushioned tool holding structure that is itself supported from the guide column by a resilient recoil assembly is herein disclosed.

Abstract: A tool, in particular a power screw driver, comprises an output shaft which is rotatably mounted in a housing and is driven by a motor. The output shaft extends substantially coaxially to a longitudinal axis of the housing. In order to improve a tool of the type described in such a manner that the tool can be held comfortably, in controlled manner and with little force, a grip sleeve which is rotatable relative to the housing is fitted over the housing, and at least one damping device that counteracts a pulse-like rotation of the grip sleeve relative to the housing is disposed between the housing and the grip sleeve.

Abstract: This invention relates generally to an impact tool. The present invention provides a vibration isolated impact tool wherein an impact mechanism and a motor assembly are arranged into a cartridge assembly. An elastomeric member resiliently connects the cartridge assembly with a housing. The cartridge assembly is free to move axially and rotationally within the housing. The elastomeric member absorbs axial vibration and torsional vibration, reducing the vibration transmitted to an operator.

Abstract: An impact mechanism, such as an impact wrench is provided and includes a motor, a shaft rotatable about an axis and coupled to the motor and having a first shaft groove with first and second axial ends and a hammer disposed about the shaft and having a first hammer groove. A ball is disposed in the first hammer groove and in the first shaft groove and couples the hammer to the shaft for relative axial and rotatable movement, with the ball moveable along the grooves. The wrench also includes a rotatable anvil for coupling to a load, a bias member resiliently biasing the hammer axially into engagement with the anvil and stop structure disposed along the shaft for engagement with the hammer to limit axial movement of the hammer away from the anvil so as to prevent the ball from contacting the second axial end of the first shaft groove.

Abstract: A hydraulic breaker for absorbing and reducing vibration and noise generated from the breaker and for reducing debris and dust scattered from the impact tool during using the breaker is provided. Space between main body of the breaker and outer housing is filled with fluid supplied from outside of the outer housing. Fluid hose is connected to a fluid hole formed on the outer housing to supply fluid into the space. Upper absorber is disposed between a bracket and upper portion of the main body, lower absorber is disposed between front cover of the outer housing and front head portion of the main body. Side absorbers are disposed between sidewall of the outer housing and outer cylindrical sidewall of the main body to keep a distance between outer housing and main body and to provide the space filled with fluid. Fluid, such as water, filled in the space is ejected through holes formed on the front cover of the outer housing.

Abstract: An impact structure for an impact power tool comprises: a hammer body rotatable by means of a driving actuator, and having at least one pawl member having an impact contacting area; and an operation body for rotating a bit for the impact power tool, having at least one wing member having an impact contacting area, which can be brought into contact with the impact contacting area of the pawl member. The operation body is rotated by intermittently hitting the pawl member of the hammer body against the wing member of the operation body in a rotational direction of the hammer body. The impact contacting area of the pawl member can be brought into point-contact or line-contact with the impact contacting area of the wing member.

Abstract: A pneumatic hammer has a housing, a handle, an air passage, a sleeve, a cylinder, an actuating head, a reciprocating valve and two buffers. The handle extends from the housing. The air passage is defined in the handle and communicates with the housing. The sleeve communicates with the housing and is slidably mounted in the housing. The cylinder is securely mounted in the sleeve. The actuating head is slidably received in the cylinder. The reciprocating valve is mounted on one end of the cylinder. A buffer abuts each end of the sleeve to provide a shock absorbing effect to the sleeve. Consequently, the shock caused by the actuating head will not be directly transmitted to the housing and handle. The control of the pneumatic hammer can be improved. In addition, an annular recess not aligning with the air passage is defined in the outer periphery of the sleeve and at least one inlet port is defined in the face defining the recess.

Abstract: A stud driver for driving fastener studs in place with the aid of a propelling piston moved by a propellant contains a return spring concentrically surrounding a piston rod of the propelling piston. The return spring has roughly the shape of a relatively thin-walled cylindrical sleeve of elastomeric material reinforced at regular intervals by metallic ring disks. These metallic ring disks prevent any uncontrolled deformation of the elastomeric sleeve in high-speed movement of the propelling piston.

Abstract: An impact mechanism, such as an impact wrench is provided and includes a motor, a shaft rotatable about an axis and coupled to the motor and having a first shaft groove with first and second axial ends and a hammer disposed about the shaft and having a first hammer groove. A ball is disposed in the first hammer groove and in the first shaft groove and couples the hammer to the shaft for relative axial and rotatable movement, with the ball moveable along the grooves. The wrench also includes a rotatable anvil for coupling to a load, a bias member resiliently biasing the hammer axially into engagement with the anvil and stop structure disposed along the shaft for engagement with the hammer to limit axial movement of the hammer away from the anvil so as to prevent the ball from contacting the second axial end of the first shaft groove.

Abstract: A hammer holder, provided between a retainer sleeve and a cylinder, slidably holds an intermediate member in an axial direction. A predetermined clearance is maintained between the hammer holder and the retainer sleeve. The hammer holder has a recessed portion which is engageable with a flange of the intermediate member so as to restrict the slide movement of the intermediate member. A cushioning member receives a percussion force when the flange is stopped by the recessed portion. The clearance restricts a compression amount of the cushioning member so that a predetermined life of the cushioning member is assured.

Abstract: A compressed-air-operated percussion mechanism includes a housing, a percussion body and a balancing body, which form an operating chamber therebetween. A secondary valve seals the operating chamber during an operating stroke and opens the chamber to evacuate compressed air after the termination of the operating stroke. A primary valve is connected to the compressed air inlet passage and intermittently opens to provide compressed air to the operating chamber.

Abstract: A manually operated leak detection device used in locating fluid leaks in a ground surface includes an elongated rod and a handle transversely fixed thereto. The invention is improved by fixing an anvil on the rod; slidably mounting a first collar on the rod above the anvil; slidably mounting a second collar on the rod below the anvil; connecting and spacing the first and second collars by a pair of parallel guide rods passing through the anvil, each of the guide rods lying on one side of the rod; providing a protective sheath over the anvil, the first and second collars and the guide rods, the sheath being connected to the second collar; and slidably mounting a handle over the rod and a top portion of the first collar, the handle being secured to the sheath at the top of the first collar.

Abstract: A percussion drill and/or jack hammer has a handle that is spring-buffered against the hammer housing which has at least one straight guiding track running parallel to the longitudinal axis of the hammer. The handle can be moved to a limited extent along the guiding track in relation to the hammer housing and is spring-buffered in such a way that its movement against the guiding track is limited on all sides.

Abstract: A improved apparatus for decelerating a piston and impacting rod assembly within a single stroke foundry impactor utilizing a non-metallic deceleration piston slidably positioned within a pressurized deceleration chamber mounted proximate the end of the bore containing the impactor piston and impacting rod assembly. The deceleration piston is biased towards the impactor bore by pressurization of the deceleration chamber, such that upon a stroke of the impactor, the residual kinetic energy of the piston and impacting rod assembly is absorbed by the biased deceleration piston.

Abstract: An impact hammer having a non-mechanical connection between the driving piston rod and the impact ram. The non-mechanical connection includes an annular body portion connected to the lower end of the piston rod which is received in a cavity in the top surface of the impact ram, and an elastomeric ring is held in facing grooves in the cavity and the annular body member to constitute the sole connecting element between the piston rod and the impact ram.

Abstract: A power assisted roofing shovel for removing shingles and attached nails from a roof to facilitate re-roofing. The shovel comprises a handle, a shovel blade, a trigger mechanism, and a mechanism for reciprocating the shovel blade. The mechanism for reciprocating the shovel blade may be an air hammer, an electric motor, a solenoid, or other power assisted device. The handle is an elongate hollow cylinder having the trigger mechanism attached to its rearward end, the shovel blade attached to its forward end, and a reciprocating mechanism there between. The shovel blade has a generally flat leading edge adapted for removing roofing materials and a rearward shank. A bracket member, extending rearward from the shovel blade, is adapted to slidably connect the shovel blade and the handle for reciprocal movement of the shovel blade.

Abstract: A high pressure gas operated setting tool and including guide cylinder, a fastening element guide (6) arranged, in a setting direction, in front of the guide cylinder and axially displaceable against a spring-biasing force in a direction opposite to the setting direction by a maximum amount (S), a drive piston (8) axially displaceable in the guide cylinder, a return device for displacing the drive piston to its ignition-ready position, and an elastic resetting element (9), surrounding the stem (82) of the drive piston and extending between the stop (73) of the guide cylinder (7) and a front, in the setting direction, end surface of the drive piston head (81), the resetting element (9) having a length corresponding at least to a maximum distance (A) between the stop (73) and the front end surface (83) of the drive piston head (81) reduced by the amount of the axial displacement of the fastening element guide (6).

Abstract: Power drivers are commonly used in production to tighten fasteners such as nuts and bolts. The socket which engages the fastener is normally coupled to the drive shaft of the power driver by a square male end on the drive shaft and a complementary square female connector on the socket. These components are not produced to close tolerances and as a result there is substantial play permitting misalignment of the rotational axes of the drive shaft and the socket and some rotational freedom between the drive shaft and the socket. In accordance with the invention an anti-vibration adaptor is provided comprising a sleeve containing a cylinder of resilient material which surrounds a portion of the drive shaft and a portion of the socket, including the point of coupling, sufficiently closely to minimize misalignment of the rotational axes of the drive shaft and the socket and reduce rotational freedom.

Abstract: Disclosed is a reciprocating pneumatic tool that includes a retainer mechanism for preventing the piston from freely exiting the barrel of the tool when the retaining sleeve and workpiece are removed. The retainer mechanism does not interfere with the functional operation of the tool when the workpiece and sleeve are attached to the tool. The retainer mechanism is mounted distally around the butt of the workpiece such that no contact occurs with the retainer mechanism or the piston.

Abstract: A hydraulic hammer having an improved buffer assembly is provided. The hydraulic hammer includes a housing, a top cover plate connected to the upper portion of the housing, a hammer assembly installed in the housing, and a buffer assembly for supporting the hammer assembly, installed between the top cover plate and the hammer assembly, in which the buffer assembly includes a top buffer contacting the upper portion of the hammer assembly and formed of an elastic material for absorbing impact, and a sliding plate is disposed between the top buffer and the top cover plate. The hydraulic hammer reduces the repeated banding stress applied to the hammer assembly.

Abstract: The invention relates to an explosive powder charge operated bolt-setting tool having a bolt guide (2) which has a through bore (4) for explosive powder charge actuable driving piston (5), a ball brake being provided for the driving piston (5), which brake is designed as a freewheel for the return of the driving piston (5) and comprises a recess (9), which is open radially towards the driving piston (5) and has two spring-loaded brake balls (12) each of which are accommodated therein, and which bear against the driving piston (5) and which can be moved, with maximum and minimum spring loading, between two axial stops (3, 16) along an oblique surface (15) which widens conically at an acute angle towards the driving piston (5).

Abstract: A tool having an operating element that is driven by an integrated power drive for the percussive, pounding or vibratory loading of a material to be worked, in particular a tamper, a vibration plate or a vibration roll for ground compaction or a hammer for breaking and/or drilling operations, can be guided using a handle. This handle is actively vibration-damped by at least one actively controlled or regulated compensation element, which counteracts the transmission of a vibration to the handle and which, depending on the vibration that can be transmitted to it and is produced in and/or on the tool, produces a compensating force and/or movement in the potential vibration transmission path from the location of production of the vibration to the handle.

Abstract: A tool, in particular a power screw driver, comprises an output shaft which is rotatably mounted in a housing and is driven by a motor. The output shaft extends substantially coaxially to a longitudinal axis of the housing. In order to improve a tool of the type described in such a manner that the tool can be held comfortably, in controlled manner and with little force, a grip sleeve which is rotatable relative to the housing is fitted over the housing, and at least one damping device that counteracts a pulse-like rotation of the grip sleeve relative to the housing is disposed between the housing and the grip sleeve.

Abstract: A high pressure gas-operated setting tool, and including a driving piston (21, 41, 61, 81) displaceable in a piston guide (7, 27, 47, 67) and having a stem (8, 28, 48, 68) and a head (9, 29, 49, 69), and a return member surrounding the stem (8, 28, 48, 68) and arranged between a stop (17), provided on the piston guide (7, 27, 47, 67) and facing in a direction opposite to a setting direction, and a front, in the setting direction, end face (18, 38, 58, 78) of the head (9, 29, 49, 69), with the return member being formed as a hollow cylindrical structural member of an elastic material and having a plurality of openings (12, 32, 34, 52, 72) which alternate, in a longitudinal direction, with layers of the elastic material.

Abstract: A hydraulic ramming apparatus including an apparatus body (14) having a cylinder bore (23) and a guide bore (24) that are successively formed to each other in the apparatus body (14). A piston (30) is slidably inserted into the cylinder bore (23) so as to be reciprocable within the cylinder bore (23). An upper pressure-receiving chamber (31) is defined at an upper end portion side of the piston (30), and a lower pressure-receiving chamber (32) is defined at a lower end portion side of the piston (30). A ramming tool (19), having a rod body (35), can be detachably inserted into the guide bore (24). Also, a mechanism for moving the rod body (35) is provided so as to follow upward movement of the piston (30).

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

Abstract: A setting tool, actuated by highly compressed gases, for driving fastening elements into a receiving material, has an axially extending piston guide (7) forming an axially extending borehole (20) for a driving piston (21) axially displaceable in the borehole and made up of a head (9) and a shaft (8) projecting axially in a driving direction from the head. To return the driving piston (21) to a starting position after a fastening element is driven, three axially extending conical compression springs following one another and encircling the piston shaft are positioned between a stop (17) in the piston guide (7) and an end surface (18) of the piston head. Damping elements (14) are located between adjoining compression springs. In the compressed state of the compression springs, the coils in each spring are in a common plane with one another and are free of contact with one another.

Abstract: A percussion tool, such as a drill or a chisel tool, including a percussion mechanism (7), a tool chuck (1), and a damping member (8) arranged between the tool chuck (1) and the percussion mechanism (7) for damping rebounds of a header (9) axially displaceable in the tool chuck (1), with the damping member (8) having, arranged one after another in the operational direction, a stop disc (86), an elastic ring (83), and a transmission element (81) having a cavity for receiving both the stop disc (86) an the elastic ring (86).

Abstract: A portable impact tool driver is removably attachable to a drive spindle or shaft of a conventional power tool. The impact tool driver has a body member with a drive shaft configured with the body member so as to be rotationally driven thereby. A hammer member is rotationally coupled to the drive shaft and is rotationally driven by the drive shaft. The hammer member is also axially movable along the drive shaft. The hammer has a first impact face configured thereon with at least two impact drivers defined on the impact face. A coupling drive mechanism is disposed between the drive shaft and the hammer member and imparts a rotational and longitudinal movement to the hammer member. An anvil member has a second impact face opposite the first impact face with an impact receiver configured thereon for periodic impacting engagement with the impacted drivers.