Abstract: To provide the pistons of internal combustion engines with profiled ring grooves in a simple manner. To this end, the profile is produced by laser beams.

Abstract: The aim of the invention is to prevent deposition of material on the piston ring flank (6) of a piston ring (3) for the piston (1) of an internal combustion engine. To this end, said piston ring is provided with channels (7) which are distributed on the circumference of said piston ring flank and which preferably are positioned radially thereon. Said channels are produced on the piston ring in a simple manner by using a laser.

Abstract: The invention relates to a piston for internal combustion engines whose piston head presents an annular cooling channel which on its end open towards the piston shaft is closed off by an appropriately shaped wall element which is radially divided in at least one place. The aim of the invention is to improve heat dissipation in such a piston. To this end the periphery of the wall element is provided with several radially arranged, evenly distributed transverse walls which extend axially into the cooling channel.

Abstract: The aim of the invention is to provide the pistons of internal combustion engines with profiled ring grooves in a simple manner. To this end, the profile is produced by laser beams.

Abstract: The invention aims at reducing the weight of a box piston having a running surface, the width in the pressure side is different from the width of the running surface on the counterpressure side. To this end, the piston has at least one bent channel that is cast using bent sleeves and is located at least partly above the bolt hubs with a tapering cross section extending approximately in the direction of pressure-counterpressure.

Abstract: In a light-metal piston for highly stressed internal combustion engines with a combustion chamber in the piston head, in order to keep the stresses at the edge of the combustion chamber low without unnecessarily increasing the stresses in the support and the gudgeon pin boss, the following features are provided in combination: the combustion chamber in the piston head is not reinforced; the drilling of gudgeon pin boss is widened (crowned) at and towards its inner end at least in a partial region X of its entire length; the drilling in each gudgeon pin boss is a shaped drilling widening conically from the outside at least in a partial region Z; the drilling of each gudgeon pin boss has two oblique wells running from its inner end.

Abstract: A light metal piston for highly stressed internal combustion engines has a combustion cavity in the piston head. In order to keep low the stresses at the edge of the combustion cavity without unnecessarily increasing the stresses in the support and hub of the piston pin, the piston has the following combination of characteristics: the combustion cavity (5) in the piston head (4) is not armoured; the bore (9) of each piston pin hub (8) is flared (cambered) towards the inner end of the hub in at toast the inner end (10) of a partial area X of the total length of the hub bore; the bore (9) of each piston pin hub (8) is designed as a molded bore (9) that is outwardly enlarged with a substantially conical shape at least in one partial area Z; the bore (9) of each piston pin hub (8) has on one side a slanted pocket (12) that starts at its inner end (10).