| 摘要 |
840,686. Moulding bearings. WHITE, C. S. July 3, 1957 [Nov. 1, 1956], No. 21106/57. Class 87(2). [Also in Groups XXV and XXXIV] A bearing surface is formed between two elements, and on one of them, by applying a layer of woven low-friction fluorocarbon material to the surface of one of the elements and injection moulding backing material into a space between the other element and a thin backing layer applied to the woven material. Cylindrical bearing elements are made by forcing synthetic resin material 35, Fig. 5, by a piston 36 around sleeves 30 comprising an inner layer of a woven fabric of polytetrafluoroethylene adhered by phenolformaldehyde or other synthetic resin to an outer layer of a woven fabric, e.g. of cotton or glass fibres. Three sleeves 30 are mounted on spools 25 and held by clamps 33 in a bore 32 whilst the material 35 is applied to the middle sleeve 30 through an orifice 34. When the material 35 has hardened on the middle sleeve the clamps 33 are released, the right hand spool is removed and a new spool fed into the left hand end of the bore 32. Alternatively the apparatus may comprise a number of orifices 34, and the bore 32 may contain more than three spools. The material 35 may alternatively be rubber or powdered or molten metal. The bearing element of a ball joint may be formed by covering the ball 41, Fig. 6, with a cap 44 of the Teflon-cotton laminate, and forcing synthetic resin or metal 49 around the cap 44 in a housing comprising stampings 42, 43 and a base 45. The cap 44 is shaped by a die plunger 57, Fig. 8, which presses a sheet of the composite material 23, the edges of which are held between annular members 51, 54. Alternative methods of applying the cap 44 to the ball 41 are described, and the cap material may contain wire reinforcement. The invention may be used in the manufacture of an "A" frame for supporting the wheels of a motor vehicle on a chassis frame and comprising a stud 40, Figs. 14 and 15, carrying the ball 41 of a ball joint at the apex of the " A ", and balls 81 of ball joints connected by a rod 79. The balls 41, 81 are covered with caps 44 of the composite material 23, and the rod 79, balls 41, 81 and the stud 40 are placed in a mould into which metal or synthetic resin is injected to form the A-frame integrally with the covering of the bearing caps 44. In other applications bearing surfaces are provided, respectively, on the thread of a nut employed in the steering mechanism of a motor vehicle, and in a transverse hole through the end of a connecting rod for receiving an apertured ball. |
