Abstract: A tool bit for a chisel or a hammer drill, in particular, a insertable chisel or insertable drill for power-driven drill and chisel hammers, has an insertion end, with a chisel shank or drill shank, and a chisel head or drill shank located opposite the insertion end. The diameter of the shank increases in the direction of the chisel head at least once from a first, small diameter to a second, large diameter and decreases again from this to a small diameter or forms at least one bead.

Abstract: A hand power tool has a percussion mechanism; a drive motor that drives the percussion mechanism; a conversion element for converting a movement of the drive motor into an axial movement; and an operating unit that adjusts a rotary movement of the conversion element within a percussion period depending on at least one optimization criterium.

Abstract: A fuel injector for internal combustion engines, the injector a nozzle needle axially guided for movement in a nozzle body to opens or close off at least one spray hole for a fuel injection, having a valve piston is guided so as to be axially moveable in a holding body and controls the opening and closing movement of the nozzle needle, having a valve piece in which the valve piston delimits a control space which is connected to a high-pressure side and which is connected by means of a control valve to a low-pressure side, and having a leakage oil return line which discharges leakage oil out of the region of the holding body. The leakage oil return line runs at least partially in the valve piece.

Abstract: A hammer mechanism for a hand-guided machine tool, in particular for a rotary hammer, percussion hammer, or impact drill, has a drive piston (11), which is supported so that it is able to move axially in a guide tube (13) and is able to be motor driven via a gear mechanism (17) into a reciprocating, axial stroke motion, and has a hammer that is contained in an axially movable fashion in the guide tube and acts on a tool and, together with the drive piston (11), delimits a compression chamber in which an air cushion is enclosed. In order to be able to freely embody the chronological curve of the stroke path of the drive piston (11) for optimization purposes, e.g. to reduce pressure peaks in the compression chamber, the gear mechanism (17) has two meshing nonround gears (18, 19), whose rotation axes (20, 21) are situated a fixed distance (a) apart from each other.

Abstract: A hand power tool has a percussion mechanism; a drive motor that drives the percussion mechanism; a conversion element for converting a movement of the drive motor into an axial movement; and an operating unit that adjusts a rotary movement of the conversion element within a percussion period depending on at least one optimization criterium.

Abstract: The invention relates to a chisel (1) or a hammer drill, in particular insertable chisel or insertable drill for power-driven drill and chisel hammers, with an insertion end (2), with a chisel shank (3) or drill shank and with a chisel head (4) or drill shank located opposite the insertion end (2). In this case, the diameter of the shank (3) increases in the direction of the chisel head (4) at least once from a first, small diameter to a second, large diameter and decreases again from this to a small diameter or forms at least one bead (8).