| 摘要 |
917,062. Ball-and-socket joints. LEMFORDER METALLWAREN G.m.b.H. June 12, 1959 [June 12, 1958], No. 20233/59. Class 65 (2). The ball head comprises a metal core 8 having a frusto-conical portion and coated with a layer 9 of synthetic plastic material, preferably resilient polyurethane having a scleroscope hardness of at least 90. The thickness of the layer is between 1.5 and 4 millimetres, and it may be anchored to the core by an adhesive or by forming the core with ribs, recesses or bores. The polyurethane may be obtained by cooling a melt which has been mixed with molybdenum disulphide, fluorinecontaining hydrocarbon, graphite or silicon oil to increase the lubricant properties. The surface of the ball head may be formed with lubricant grooves and the ball pin 1 may pass through a lubricant reservoir formed by a bellows 7. The socket 3 may be made of steel compression moulded to harden the surface, or may comprise a rough stamping lined with injection moulded thermoplastic material, e.g. polyamide, polycarbonate, polystyrene or a fluorine-containing high polymer, or a castable resin, e.g. an epoxy or unsaturated polyester resin which may be reinforced with glass fibres. Preferably, the lining is hardened by a high-frequency heating process and simultaneously given its final shape by compression moulding. If the socket is lined, it may be made of a light metal by die-casting or pressure-casting. |
