GB1232747A - - Google Patents

Abstract

1,232,747. Electron beam irradiation apparatus. T.I. (GROUP SERVICES) Ltd. 16 April, 1970 [18 April, 1969], No. 19921/69. Heading H1D. An electron beam irradiation apparatus for irradiating material such as paint which is moved past the apparatus, is provided with at least four separate windows along the line of travel, the beam being scanned to emerge from each window in turn. The scanning waveform may be such that the beam repeatedly passes through each window in turn in one direction (Fig. 2, not shown) or such that the beam passes along the line of windows and back again (Fig. 3, not shown) ; in either case the beam dwells at each required window and then jumps rapidly to the next one. The scanning may be electrostatic (as illustrated) or magnetic, and the beam may be scanned transversely to cover the width of the work as an alternative to using a wide beam. The scanning waveforms may be linked to the EHT supply to avoid mis-registration if the latter varies and may be synchronized with the mains supply to minimize variations in electron intensity from point to point in the scanning. The speed of transport of the work should be so related to the scanning speed that each element of the work is irradiated several times at each window. In the example shown there are six windows, but there may be as many as twelve ; the part doses delivered to each part of the work should be separated in time by intervals similar to the free radical half-lifetime of the reaction being induced.