GB700417A - Improvements in or relating to methods and apparatus for gluing together a multiplicity of elements - Google Patents

Abstract

700,417. Dielectric heating. GENERAL ELECTRIC CO., Ltd., and SMITH, R. March 14, 1952 [March 14. 1951], No. 6170/51 Class 39 (3) Apparatus for gluing together a number of elements includes a laying-up table 11 from which the elements are transferred by a pusher device 10 to a press 12, and the return movement of the pusher device from the press operates, in succession, means for applying pressure to the elements in the press to maintain the work flat, means for applying transverse pressure which tends to squeeze together the glued surfaces, and finally means for switching on the high frequency supply. The latter is applied to the opposed press platens 30, Fig. 2, the lower one only being shown, which platen is moved upwardly by a number of pneumatically operated double acting rams 31, only one of which is shown, to compress the work and maintain it flat. The pusher device or loader 10 is operated by a double acting ram 20, and a horizontal pressure member 32 is operated by a number of similar rams 33. Air is led from a common supply 22 through a change over valve 23 to the ram 20, and the loader speed is controlled by throttle valves 24, 25. Similarly the rams 31 and 33 are supplied with air through change over valves 34 and 25 respectively. The upper press platen, not shown, is fixed and has along one side a stop of insulating material opposite the pressure member 32. The change over valves are electrically operated, and normally air is admitted to the side of the pistons of rams 31 and 33 such that they retract, and to the ram 20 such that the loader is moved to its outer position. A protuberance 26 on the piston rod 21 operates during the return stroke of the loader from the press, electric switches 41-43 which, in turn, operate a number of relays controlling the energization of the operating windings of the valves 23, 34 and 35. The energisation of these windings causes pressure to be exerted by the rams 31 and 33 in succession and finally, the operation of a switch 44 effects a high frequency supply to the press. A timing device controls the duration of the high frequency supply, after which time all the relays are automatically de-energized. Removal of the vertical pressure is delayed until the horizontal pressure has been removed or reduced, and an air pressure switch ensures that heating current is not applied if the pressure is inadequate. The work, after treatment, is discharged on to a table 14 having rollers 15. The Provisional Specification states that the valve operating switches may be adjusted in the direction of movement of the pusher member, so that they are operated at an earlier or a later stage in the loader travel.