GB1096646A - Means for piston-skirt lubrication in reciprocating engines - Google Patents

Abstract

1,096,646. Bearings; lubricating; pistons. HEDEMORA VERKSTADER A.B. May 13, 1965 [May 13, 1964], No. 20350/65. Headings F2A and F2T. The amount of lubricant which is supplied to a space formed between a piston skirt and the wall of a cylinder in which the piston moves, is controlled by a temperature-sensitive valve so that, as the temperature rises to a predetermined temperature, the flow of lubricant is reduced or terminated. In an embodiment, a piston 11, Fig. 1, is mounted in a cylinder liner 10 and has a transverse bore therein which receives a piston-pin 12 having a connecting- rod 13 journalled thereon. A disc 17, having a peripheral groove 8 which receives a sealing ring 20 therein is mounted at each end of the transverse bore of the pin 12. Each disc 17 is retained by a snap-ring 18 and has radial recesses 9 therein. The pin 12 has four circumferentially-spaced bores 14 which are supplied with pressurized lubricant from a passage 15 in the connecting-rod 13 and has radial bores 16 therein which convey lubricant to the bearing surfaces of the pin and its bore. Lubricant is also conveyed from the bores 14, through axial passages 21 in the pin 12, through a gap 19, Fig. 2, in the sealing-ring 20, to a space formed between the disc 17, Fig. 1, a cylindrical liner 10, a piston-ring 22 and a piston-ring 23. Passages 7 and 24 in the piston dissipate excess pressure and lubricant respectively. As the engine temperature rises after starting, the sealing-ring 20 expands and the gap 19 is reduced, thus decreasing the flow of lubricant therethrough. In modifications, each disc 17 has no sealing-ring, is made of material such as P.T.F.E. and expands to seal the bore when the temperature reaches the required limit; each disc seals the bore, has holes therethrough which coincide with an annular groove therein which receives a splitsealing ring; each disc has an axial bore which, when the engine temperature rises, is closed by one end of an expandable rod; and plugs, having an axial bore therein, are mounted at each end of the bore of the pin, the axial bore of each plug being blocked by an expandable rod when the temperature rises a required amount.