GB1192643A - Improvements relating to Dielectric Heating Apparatus - Google Patents

Abstract

1,192,643. Embossing. RADYNE Ltd. 9 July, 1968 [28 July, 1967], No. 34872/67. Heading B6J. [Also in Divisions B5 and H5] Dielectric heating apparatus for bonding the margin of a cover material 34 to the margin of a panel 36 includes front and rear marginal electrodes 10, and 26a, 26b, 26c, 26d, the workcontacting surface of the rear electrode being of smaller area per unit of length, for example by having notches 30, Fig. 3 (not shown), or recesses 32, Fig. 3b (not shown). Four side plates 24 each carry a portion 26a, 26b, 26c or 26d of the rear electrode, the plates 24 being moved hydraulically towards the welding position with a "tilt- and-slide" movement provided by a cam 48 on each plate 24 resting on a roller 50. The forward and downward movement of the plate 24 smoothes the margin 34a of the cover material 34 over the rear surface of the hardboard panel 36 before an upper pressure plate 52 exerts pressure on the rear electrode assembly and packing plate 18. The front electrode assembly includes the marginal electrode 10 and embossing electrodes 14. Electrode 10 may be increased in width and resiliently mounted, Fig. 7 (not shown). The notched electrodes produce bonded areas 38 and pockets 40 for taking up slack material. 42 is a foam layer.