| 摘要 |
634,923. Presses. MINNESOTA MINING & MANUFACTURING CO. Aug. 13, 1946, No. 23974. Convention date, Aug. 27, 1945. [Class 140] A pressing device useful in applying a film 11 to a metal stamping 7 or to the wall of a vehicle comprises a flexible diaphragm 15 carried by a rigid frame 14 which, with the aid of a gasket 19 is adapted to form an evacuable space with a rigid base 12, with a second diaphragm and frame, or with the wall to which the film is to be applied. The space between the diaphragm 15 and the base, second diaphragm, or wall, is evacuated, e.g. through suction pipe 20, so that atmospheric pressure acting on the diaphragm presses the film 11 on to its backing 7 or the vehicle wall. The gasket 19 which may be of rubber tubing is shown attached to the base 12., In the other two forms it is attached to a frame 14. A layer of wire gauze 24 may be laid on the base and overlaid with strips 26 of thin sheet metal. The film 11 may be a sheet of synthetic resin, and the adhesive used for attaching it to the base may be heat-activable, the necessary heat being applied by immersing the evacuated device in hot water or by radiant heat. The modified device with two opposed flexible diaphragms may be used for applying films to both sides of a sign or other backing. |
