| 摘要 |
1275494 Bonding metallic members to polymeric material NATIONAL CASH REGISTER CO 23 Sept 1970 [6 Oct 1969] 45245/70 Heading B5A In a method of bonding metallic supporting springs 31 to a print hammer 28 of moulded polymeric material, that part of the spring which is to be embedded in the hammer body is coated with a thermosetting adhesive 60 and then positioned in a moulding die, the moulding die then being filled with molten polymeric material which is thereafter solidified to form the hammer body; the adhesive is elastomeric or is cured to an elastomeric state during the bonding process. The spring may be shaped as shown, so as to provide a mechanical anchor age in addition to the adhesive bond. A plug 30, which may be of the same material as the hammer, is positioned within the shaped end of the spring after moulding of the hammer, and is also coated with adhesive before insertion. A positioning pin, which fits inside the curve of the spring, prevents moulding material from entering the hole defined by the spring during moulding and is removed to permit insertion of the plug 30. The polymeric material used is preferably glass reinforced nylon, and the adhesive is preferably an epoxy resin/nitrile polymer mixture or a polyurethane based adhesive. |
