| 摘要 |
955,179. Assembling resilient bushes. J. & S. ENGINEERS Ltd. Oct. 29, 1962 [Nov. 3, 1961; May 23, 1962; Sept. 10, 1962], Nos. 39412/61, 19830/62 and 34512/62. Heading F2S. [Also in Division B3] A method of providing a composite insert e.g. a lead through conductor assembly in a previously imperforate sheet of material, one of the insert components being of a softer material than that of the sheet comprises placing the sheet between a ram and die of a press, retaining the separate insert components between the ram and the sheet so that said components are successively aligned with the die and each other, moving the ram and die together to force said components together to constitute the composite insert, shrouding the space between the ram and the sheet to enclose at least said one component of the insert and to restrict cold flow of the material thereof and continuing said movement of the ram and die to force the softer material portion of the insert into the sheet while a part of the sheet is sheared out into the die. A ridged or grooved metal pin 2 inserted in a ram bore 12 is forced into a cylindrical billet 10 e.g. nylon, aluminium or soft brass contained within a shroud 8, positioned above a sheet e.g. metal or synthetic resin bonded plastic (S.R.B.P.) board which is itself positioned over a die 5 having a square or circular aperture. The pin initially pierces the sheet whilst continued downward movement of the ram compresses the billet, the upper face of which is shaped by a ram recess 11 until the hydrostatic pressure exerted by the billet shears a piece of material from the sheet allowing the leading end of the billet to pass through the aperture so produced and expand thereby keying itself to the sheet. The ram is withdrawn and the die expanded to permit removal of the assembled insert. The upper portion of the insert bush 3 is circular whilst the lower portion is circular or rectangular. In a first modification a rigid insert plate 16 positioned in an annular plastic ring 17 is similarly inserted in a sheet 18 until the plate lies in the plane of the sheet. A recess 24 of a ram 23 cold forms the ring over the plate. In a second modification a taper ended screw 28 and a plastic slug having a bore diameter less than the minor diameter of the screw is similarly assembled in a sheet, the screw which is subsequently removed serving to form a screw thread in the slug. The tapered bore produced in the slug acts as a locking portion for retaining screws which are subsequently screwed through the insert. To produce more controlled locking the leading end of the insert may have slots formed therein. Specification 931,875 is referred to. |
