Piston head mfg. process - involves using compressed elastic inserts for cooling chamber to reduce heat at combustion chamber edges

摘要

In mfg. a piston head, for high power internal combustion and especially diesel engines, the piston head (1) of a structured piston has a combustion chamber (2), a piston ring zone (3), drillings (4) the gudgeon pins for the lower piston rod linkage, and a cooling chamber (5). The upper section (1) is prepared above the line (55) separating it from the hub section (4). A peripheral groove (10) surrounds the cooling chamber (5) which, at the outermost surface of the upper section (1) is closer to the dividing plane (SS) and in another plane is even closer to the dividing plane (SS). A notch (11) at the outer line of the cooling chamber (5) is at the inner surface of the piston head (1). A peripheral contour groove (15) is at the lower level of the under crown (21). A partially closed unit (6) of an elastic material, pref. in a round shape, matches the outer and inner (D1) dimensions of the coolant chamber (5), close to the dividing line (SS) and with optional clamps and radial edges to form a radial gap at least at a coolant oil channel. The elastic component (6) is compressed, by bringing the edges together to narrow the gap in the ring so that the inner dimensions are smaller than the gap (D) between the outer limits of the chamber (5) near the dividing plane (SS). The compressed part is inserted into the piston head (1) and forced into the chamber for positioning at the groove (10) and notch (11), and the compression on the part (6) is relaxed. A similar elastic partially closed part (13), with an inner contoured edge (14) for oil retention, is compressed for insertion into the groove (15), and then its diametrical compression is relaxed. The upper part (1) of the piston head assembly above the dividng line (SS) is bonded to the gudgeon pin (4) part below the line (SS). ADVANTAGE - The piston gives a good oil cooling action, particularly at the edges and piston ring zones of the combustion chamber.