Abstract: A handle frame (20;20.sup.1 ;120) for a portable power tool, wherein the portable power tool comprises a housing (10), a hammer mechanism (13) provided in the housing (10), and an elongate working implement (12) having an impact receiving end extending into the housing (10) for receiving impacts in a longitudinal direction from the hammer mechanism (13). The handle frame includes two parallel elongate side members (21) disposed on opposite sides of the housing (10) and extending in a first plane (x--x) parallel to a tool application direction, each of the side members (21) having a forward end portion (21a) located in the tool application direction and a rear end portion (21b) located in a direction opposite to the tool application direction. Mountings (16,17) are provided on the side members (21) for connecting the handle frame to the housing (10) of the portable power tool in a vibration damped manner.

Abstract: A vibration-damped, machine driven tool includes a machine housing, a drive mechanism housed in the housing and operable to drive a tool projecting out from the housing, a carrier device which forms a cradle in which the machine housing is suspended, and a vibration damper coupling the carrier device to the machine housing. The machine housing and the tool are subjectable to an appropriately directed tool-feeding force via the carrier device so as to cause the tool to work on an outer workpiece. When the tool is at work, the drive mechanism generates vibrations. In order to reduce the vibrations, the vibration damper includes at least two pairs of leaf spring bridges which are fixedly mounted in abutment with the machine housing and with the cradle formed by the carrier device, and which are mutually spaced apart in a longitudinal direction of the cradle.

Abstract: In the front head (11) of a machine hammer (10), transversely disposed wedges (18) are adapted to lock the working tool (12) so that the working tool (12) is axially movable by form-restricted cooperation with recesses (16) on the working tool (12). Each wedge (18) is locked in the front head (11) by a key (20), which extends across the wedge (18) into engagement with a transverse bore (21) therein. The key (20) has a releasable locking device including a locking element affixed in the front head (11) and formed by a polyurethane block (24). The block (24) is provided with a through bore (27) and has elastically form-recovering material properties. When, for purposes of locking the key (20), the key (20) is pressed through the bore of the block (24), the block (24) is caused to expand resiliently into an annular groove (22) on the key (20), thereby locking the key (20) in the front head (11) and providing its wedge (18) locking function.

Abstract: When driving a tube (24) into the ground, primarily for subsequently loading the tube with an explosive substance and subsequent blasting of the surrounding ground, a driving rod (20) whose rear end is provided with an insert end (13) which can be connected to a percussion machine (36) is employed in the driving operation. The non-metallic tube (24) is fitted over the driving rod (20), against an axial stop (16). A forwardly located, conical sacrificial tip (28) has a base cross-section dimension (30) which corresponds to the outer dimension of the tube (24), followed by a neck portion providing a shoulder (31). The tip (28) is supported by the shoulder (31) with clamping engagement with the tube in an orifice of the tube, and forms, together with the tube (24), a unit (24, 28) which is fitted onto the driving rod (20) and brought into impact contact between an anvil surface (33) on the tip (28) and the forward end (21) of the device.

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 hydraulic breaking hammer (10) has a machine housing (11) in which a percussion motor (15) which includes a reciprocatingly movable percussion piston (17) delivers impacts to a breaking tool (13) in the front of the machine housing (11). The machine housing (11) is carried by a surrounding carrier support (18) via intermediate walls (24, 25, 26). The carrier support has the form of a shell (18) which is attached at the rear adjacent connecting devices (19), to a carrier, such as a hydraulic digging machine which aligns the machine housing (11) while the manner (10) is at work. The machine housing (11) is constructed without joints in its axial direction along the length of the housing and includes a guide passage (21) in which a percussion motor (15) is carried, this percussion motor having the form of an insert cartridge which can be clamped from the rear.

Abstract: An impulse motor for a hand held hammer machine comprises a housing (10) with a cylinder (11) therein, in which a reciprocating drive piston (40) via a gas cushion in a working chamber (44) of said cylinder (11) repeatedly drives a hammer piston (15) to impact on and to return from a tool (20) carried by the machine housing (10). The drive piston (40) has an axially protruding reduced diameter damping piston (50) thereon adapted to prevent piston encounter collision by arresting the return movement of said hammer piston (15) towards the drive piston (40) in a cooperating damping cylinder (51) provided on the hammer piston (15). The damping piston (50) has two diameterical steps (64,65) formed thereon, of which an outer step (64) is long and has a clearance relative to said damping cylinder (51) enabling during arresting a braking action therebetween by gas friction in said clearance.

Abstract: A percussive machine comprises a housing (10) with a cylinder (11) therein, in which a reciprocating drive piston (40) via a gas cushion in a working chamber (44) repeatedly drives a hammer piston (15) to impact on the neck (17) of a tool (20) carried by the housing (10). At empty blows with the neck (17) out of reach, the hammer piston (15) is thrown forwardly and caught pneumatically in a braking chamber (47) at the bottom end (12) of the cylinder (11). The braking is combined with an elastic yielding of the bottom end (12) against the action of a recoil spring (23) in the housing (10). The pressure in the braking chamber (47) during such yielding is controlled by throttling apertures (48) in the cylinder (11) uncovered by the bottom end (12). The hammer piston (15) is thus checked to halt pneumatically by throttling avoiding a collision with the bottom end (12) and takes an inactive position below ports (46) in the cylinder wall through which the working chamber (44) is relieved and ventilated.

Abstract: A hand held hammer machine comprises a housing (10) with a cylinder (11) therein, in which a reciprocating drive piston (40) via a gas cushion in a working chamber (44) repeatedly drives a hammer piston (15) to impact on the neck (17) of a tool (20) carried by the machine housing (10) as soon as a feeding force is applied via the machine housing (10) to the tool (20) and an interposed recoil spring (23) pre-stressed between fixed shoulders (28,22) in the housing (10) starts being compressed in response to tool penetration into the housing (10). Therein and within the spring (23) and around the path of movement of a piston rod (13) of the hammer piston (15) is affixed one end (26) of a sleeve (25), which by its other end forms a stop (30) limiting the penetration of the tool neck (17) into the machine housing (10) to a maximally allowable extent.

Abstract: An impact motor comprises a housing (10) with a cylinder (11) therein, in which a reciprocating drive piston (40) via a gas cushion in a working chamber (44) of said cylinder (11) repeatedly drives a hammer piston (15) to impact on and to return from the neck (17) of a tool (20) carried by the machine housing (10). A piston groove (68) is provided adjacent to the front face (70) of the drive piston (40) and the peripheral part of said face (70) is rounded (71) towards said groove (68). A piston ring (41) is of steel having a temperature expansion coefficient substantially equal to the cylinder's (11) and is ground circumferentially to have a close sliding and sealing fit in the cylinder (11). The rounded (71) drive piston face (70) is adapted to the inner diameter of said ring (41) so as to permit the ring (41) to be forced into said groove (68) undeformed to ride on a elastically centering O-ring (69) of heat resistant rubber.

Abstract: A portable hammer machine comprises a cylinder (11) in which a reciprocating drive piston (40) via a gas cushion in a working chamber (44) repeatedly drives a hammer piston (15) to impact on and to return from a tool (20) carried by the machine as soon as a feeding force is applied via the machine housing (10) to the tool (20) under compression of a spring (23) interposed therebetween. The cylinder (11) is on the one hand provided with primary ports (45) for the passage of gas to and from the working chamber (44), which ports (45) at impacting are opened above the hammer piston (15) to ventilate the working chamber (44), and on the other hand with secondary ports (46) for ventilating the volume (47) below the hammer piston (15) during its reciprocation and impacting. The spring (23) is pre-compressed in the machine housing (10) so as to balance the weight of the hammer machine when the latter is kept standing on the tool (20) with the hammer piston (15) resting against the tool (20).

Abstract: A hammer machine comprises a machine housing (10) with a cylinder (11) in which a reciprocating drive piston (40) via a gas cushion (44) drives a hammer piston (15) to impact on respectively to move away from a tool (20) carried by the housing (10). The movement of the hammer piston (15) away from the tool (20) is supported by underpressure in the gas cushion (44) and rebound. A connecting passage (52) in the drive piston (40), the cylinder (11) or the hammer piston (15) comprises a one-way valve (57) and a throttling means (53) via which the gas cushion (44) is replenished by ambient air for regulating the gas cushion pressure during operation of the drive piston. The one-way valve (57) closes to prevent escape of gas from the gas cushion (44). A damping cylinder (51) in communication with the connecting passage (52) can be provided on one of the pistons (40;15), which, when the piston tend to collide, sealingly cooperates with a damping pistons (50) on the other piston (15;40) so as to prevent collision.