Abstract: A piston having a head with ring grooves, a skirt having hub bores, and a pin, with the following dimensions:L/D=0.45-0.8H/D=0.25-0.5A/D=0.3-0.5T/D=0.45-0.8whereL=maxium length of the pistonD=maximum diameter of the pistonH=compression heightA=maximum skirt height below the bottom ring groove in a peripheral area having the approximate same skirt height of at least 45 degrees on the major thrust face of the piston with approximately symmetrical division of this area on both sides of a plane extending perpendicular to the pin axis and passing through the longitudinal axis of the piston,T=diametrically opposite distance between the hub bore ends located radially on the outside.The skirt bulges along the axis of the piston and has an oval cross-section. An axis of the hub bores is offset slightly towards the major thrust face. The piston includes a horizontal slit, which separates the head from the skirt. In a polar plane perpendicular to the piston axis the skirt has a greater ovality on the minor thrust face.

Abstract: A piston for an internal combustion engine with a separate head and skirt which are joined by a piston pin. The ring belt extends downward from the head and terminates above the pin. The space between the lower edge of the ring belt and a section of the head defines a cooling oil ring space. A depression is formed in the head and is partly defined by the section. The section has a thickness of between four percent and seven percent of the piston diameter, corresponding to an angle of zero to sixty degrees of the section with respect to a vertical longitudinally extending line. The thickness of the head above the space is six percent to twelve percent of the piston diameter. The top of the space is below the top ring groove. Above the second ring groove, the ring belt has a thickness of greater than two and one-half percent of the piston diameter.

Abstract: The technical problem is to reduce the operating noise of such a piston. It is solved by means of a piston having the following dimensions: a) A=(0.45-0.65) D; b) H=(0.25-0.4) D; c) A=(0.3-0.4) D; d) A greater than or equal to B; e) T=(0.45-0.8) D; f) the piston ribs between the annular grooves (2, 3, 4) and the rod region with a very narrow operating clearance have, in the case of a hot operating piston, approximately the same clearance in relation to the cylinder operating path. An additional improvement consists in inserting an annular jacket in the piston head in the radial region behind the annular grooves, said jacket consisting of a material having a thermal expension factor less than that of the basic piston material. In a hot operating internal combustion engine, the piston has, in the region of the ribs, a clearance which, in the direction pressure/counter-pressure reaches approximately only 3-5 times the clearance in the very narrow clearance region of the piston rod.

Abstract: A process for the production of a cast piston upper part of a two-part piston comprising the steps of casting a piston head and a ring section having a collar of tab-type segments, wherein the tab-type segments have tapered ends; and bending over the tab-type segments in the direction towards the middle of the piston to form a lower closure serving as an annular cooling oil space.

Abstract: A two-part, low compression height, open-ended hollow skirt-type piston for internal combustion engines has a piston pin creating an articulated connection of the separate skirt and head parts. Guide portions (5) protruding axially in the direction of the piston axis provide lateral guidance and support of the piston head (1) in the piston-pin-axis direction. Each of the guide portions forms a gap with the nearby gudgeon pin boss (3). The gaps receive opposite parallel flat surfaces (4) of the skirt (2). The overhanging guide portions (5) have partly circular recesses permitting assembly of head and skirt with the gudgeon pin.

Abstract: A piston, particularly for internal combustion engines, of which the bearing surfaces with which the piston comes into contact with the engine cylinder bore lie on a generated surface which runs asymmetrically to the axis of an engine cylinder accommodating the piston without clearance in the longitudinal direction of the piston and/or in the circumferential direction.

Abstract: An extremely light and low friction plunger piston for internal combustion engines, particularly Otto-type engines for private cars. The piston has the following ratios and dimensions(H/D)=0.20-0.35(T/D)=0.22-0.38(A/D)=0.15-0.25(B/D)=(A/D)whereinD=piston diameterH=compression height between a top of the head and the gudgeon pin bore axisT=distance from the radially outer boss faces to the piston axisA=axial skirt dimension below annular groove nearest the pin bore axis at a peripheral zone of the skirt extending over an angle .alpha. of 15 to 60 degrees to either side of a connecting rod oscillating planeB=axial skirt dimension below said annular groove in a direction along said gudgeon pin axis;and further wherein the distal end of the skirt is reduced radially over an axial dimension of 10-25% of an axial length of the skirt in said direction along said gudgeon pin axis, said distal end being reduced at its edge by 0.01-0.15 mm.

Abstract: In a plunger piston for internal combustion engines, having a regulating strip in the piston body, the regulating strip is arranged in the axial middle third of the height of the piston body and the regulating effect is designed so that the piston body possesses its narrowest installation play uniformly at the level of the regulating strip equally in the cold installation state and in the engine operation. Above and below this region with minimum installation play the piston body possesses spherically retracted end regions at its upper and lower ends for the generation of hydrodynamic lubricant oil wedges.

Abstract: In a light plunger piston for internal combustion engines, in order further to save weight and to achieve an elastic running behaviour, the piston skirt is reduced to three relatively narrow guide plates. The guide plates are attached through longitudinal ribs to gudgeon pin bushes suspended freely from the piston crown. On the thrust side of the piston there are two of the three guide plates which extend, seen from a 45 degrees diagonal plane between gudgeon pin axial plane and connecting rod oscillation plane, through about 15-25 degrees to each of the two sides. On the counter-thrust side only one pressure plate is provided which extends circumferentially over about 50 degrees. There is preferably no direct connection between the guide plates and the lowermost ring land.

Abstract: In connection with a plunger piston for internal combustion engines, the connecting rod, which is hinged thereto via a gudgeon pin, is laterally guided at its small end by being in abutting contact with the internal faces of the gudgeon pin bosses. For this purpose, there are provided, only in the zone at the level of the gudgeon pin axis, limited contact surfaces between the connecting rod small end and the gudgeon pin bosses. By this means, the influence of deformations of the piston on the guidance of the connecting rod is eliminated to a very large extent.