Abstract: A shaft/hub connection between a shaft rotatably driven about an axis of rotation, and a hub disposed on the shaft so as to be non-rotatable relative thereto. The hub has a conical opening and an end face at that end of the hub having the greatest inner diameter. The hub also has at least one relief groove that extends into the hub from the end face thereof. A conical shaft extension on the shaft extends into the conical opening of the hub and is held in the hub via a conical pressure connection.

Abstract: A shaft/hub connection between a shaft rotatably driven about an axis of rotation, and a hub disposed on the shaft so as to be non-rotatable relative thereto. A conical shaft extension on the shaft extends into a conical opening of the hub and is held in the hub via a conical pressure connection. The hub is provided with a stress-relieving or antifatigue arrangement for reducing the dynamic fatigue stresses that occur on the hub during operation. The shaft/hub connection is advantageously utilized for connecting the crankshaft of the internal combustion engine of a manually guided implement with a flywheel.

Abstract: A piston for a two-cycle engine having a piston head and a piston wall in which are disposed wrist pin eyes. At least one undercut is formed between the underside of the piston head and the wrist pin eyes at a distance from the piston head. The undercut extends from the interior of the piston toward the piston wall. A respective thickened portion is provided in at least one region of the piston that is rotationally shifted about the longitudinal axis of the piston by 90° relative to one of the wrist pin eyes. The thickened portion is disposed at a distance below the piston head and extends into the interior of the piston.

Abstract: A tubular handle for a manually guided implement, especially a power chain saw or the like, is provided. The handle has an essentially circular cross-section and at least one mounting portion for fixing the handle to the implement. In the area of the mounting portion, the circular cross-section is flattened to form an at least approximately planar abutment portion, beyond which a circular cross-sectional portion is retained. The abutment portion is provided for fixing the tubular handle to the implement.

Abstract: A piston for a two-cycle engine having a piston head and a piston wall in which are disposed wrist pin eyes. At least one undercut is formed between the underside of the piston head and the wrist pin eyes at a distance from the piston head. The undercut extends from the interior of the piston toward the piston wall. A respective thickened portion is provided in at least one region of the piston that is rotationally shifted about the longitudinal axis of the piston by 90° relative to one of the wrist pin eyes. The thickened portion is disposed at a distance below the piston head and extends into the interior of the piston.

Abstract: A manually guided implement, especially a brush cutter, comprising a guide tube with a guide motor at one end and a tool head that carries a rotatably drivable tool at the opposite end. A handle is disposed on a securement mechanism, and a handle carrier is disposed between the securement mechanism and the guide tube. The handle carrier is fixed in position on the guide tube along a short range relative to the longitudinal direction of the guide tube. The securement mechanism is adjustably held on the handle carrier such that the position of the securement mechanism relative to the longitudinal direction is adjustable.

Abstract: A handle of a handheld working tool has a handle pipe reinforced by at least one reinforcement element locally arranged on the handle pipe at a location of high dynamic vibration-caused deformation energy. The handle pipe and the reinforcement element are made of plastic material. A laminate that is made of fiber-reinforced plastic material can be used for making the handle.

Abstract: A handle of a hand-held working tool has a handle pipe made of a laminate with fiber-reinforced plastic material. The handle pipe is reinforced by a locally adjusted laminate structure at locations of high dynamic vibration-caused deformation energy, respectively. The laminate of the handle pipe has a base laminate and an additional laminate provided at the locations of high dynamic vibration-caused deformation energy. The additional laminate is applied to the exterior of the base laminate.

Abstract: A tubular handle for a manually guided implement, especially a power chain saw or the like, is provided. The handle has an essentially circular cross-section and at least one mounting portion for fixing the handle to the implement. In the area of the mounting portion, the circular cross-section is flattened to form an at least approximately planar abutment portion, beyond which a circular cross-sectional portion is retained. The abutment portion is provided for fixing the tubular handle to the implement.

Abstract: A portable work apparatus, especially a motor-driven chain saw (1), has a drive unit which is provided with a handle housing (3). The handle housing (3) includes an extension (9) which extends in the longitudinal direction of the work apparatus from a rearward handle (8) on the side facing away in the longitudinal direction from a guide bar (6) forward to the side facing toward the guide bar (6). The handle housing (3) is connected via antivibration elements to the drive unit. The work apparatus has a forward handle tube (4), which extends over the work apparatus transversely to the longitudinal direction and is attached with an end (10) to the free end of the extension (9) and with the other end (27) in the area of the rearward handle (8). At least one of the ends (10, 27) of the handle tube (4) is fixed via an antivibration element (11, 25, 26, 28, 34).

Abstract: A portable work apparatus, especially a motor-driven chain saw (1), has a drive unit which is provided with a handle housing (3). The handle housing (3) includes an extension (9) which extends in the longitudinal direction of the work apparatus from a rearward handle (8) on the side facing away in the longitudinal direction from a guide bar (6) forward to the side facing toward the guide bar (6). The handle housing (3) is connected via antivibration elements to the drive unit. The work apparatus has a forward handle tube (4), which extends over the work apparatus transversely to the longitudinal direction and is attached with an end (10) to the free end of the extension (9) and with the other end (27) in the area of the rearward handle (8). At least one of the ends (10, 27) of the handle tube (4) is fixed via an antivibration element (11, 25, 26, 28, 34).

Abstract: The invention is directed to a composite crankshaft for a two-stroke engine for portable handheld work tools including chain saws, cutoff machines and the like. In composite crankshafts, a crank pin is connected to a crank web by a press fit wherein the inner diameter of the press-fit bore is expanded toward its axial end in order to reduce stress peaks. In this way, the press-fit surface has a radial spacing with respect to the center longitudinal axis of the press fit which changes. The press fit of the crankshaft of the invention is so configured that the radial distance of the press-fit surface changes in dependence upon the axial spacing to the axial center of the press fit according to an exponential function having the equation f(x)=a.multidot.e.sup.b.multidot.x wherein (a) and (b) are pregiven constants, (x) is the axial spacing and f(x) is the radial spacing.

Abstract: The guide bar for a motor-driven chain saw is provided for taking highest loading and is therefore made of solid material. For weight reduction, openings are provided in the guide bar which are closed off by cover plates that are flush with the flat sides of the guide bar. The cover plates are firmly joined to the base plate of the guide bar. By means of the hollow spaces inside the guide bar, a considerable weight reduction is attained, yet the stability of the guide bar is not substantially impaired as compared to a solid guide bar, since the hollow spaces are located in the zone that is neutral in terms of bending.

Abstract: A motor-driven chain saw essentially includes a housing having a rear handle and a front handle and a drive unit attached to the housing. A guide bar for accommodating the saw chain for movement thereon is attached to the drive unit. The housing has an extension arm on the underside of the chain saw which extends to the front; the drive unit is seated on this arm and the front handle is attached to the front end of the arm. To increase torsional and bending strength, the extension arm has an S-shaped profile when viewed in cross section. The S-shaped profile has a substantially rectangular configuration and includes lower, middle and upper parts that are parallel to one another and are interconnected by two flanks. The flanks are located in planes that are parallel to the guide bar.