| 摘要 |
<p>783,743. Repairing damaged car bodies. GENERAL MOTORS CORPORATION. Nov. 21, 1955 [Nov. 22, 1954], No. 33203/55. Class 83 (4). [Also in Group XXXII] A method of repairing a damaged motor-car body, fuel tank or other sheet metal panel comprises successively applying a liquid epoxy resin and layers of glass fibres to the portion of the sheet metal panel to be repaired and permitting or causing the liquid epoxy resin to set. In an embodiment a hole 12 in a metal panel 10 is repaired by first cleaning the surfaces adjacent the hole with a hydrocarbon solvent and then indenting the sheet metal surrounding the hole to provide a secure bonding of the resin and to permit proper contouring of the patch (Fig. 4). The metal surrounding the hole is heated to evaporate moisture and two or more fibre-glass cloth layers 16 are cut to size. Catalysed resin is now applied to the sheet-metal by brushing or spraying and the first fibre-glass layer 20 is pressed into position. A second coat of resin is applied to the layer 20 and these steps are repeated to provide sufficient fibre glass layers to obtain the desired thickness of patch. The repaired area is covered with paper while the resin is setting which may be expedited by heating with infra-red lamps. Final contouring is effected by grinding, hand filing and sandpapering (Fig. 6). If the rear surface of the damaged panel is accessible a fibre-glass reinforced epoxy resin patch 23 (Fig. 9) is applied to the rear surface 25 to bond with the patch 27 on the front surface 29 of the panel. If there is a large unsupported area to be repaired where a backing is necessary chopped fibre-glass or crushed paper is used as a filler. Small holes or tears 31 may be provided adjacent any rusted area 33 (Fig. 10) to effect a secure anchoring of the patch on a badly rusted panel. Dents in panels may be repaired according to the invention as shown in Figs. 7 and 8.</p> |
