| 摘要 |
1524728 Automatic control HARRIS CORP 10 Dec 1975 [12 Dec 1974] 50675/75 Headings G3N and G3R The intensity of an A.C. mercury vapour ultraviolet lamp 2 is controlled by a closed loop including a photodiode 7, comparator 65, optical coupling 68, 61 and triac 48 in series with the primary winding 46 of a transformer. The same A.C. supply also drives a blower 6 for cooling the lamp. The lamp may be used for curing or drying ink or paint in multi-colour offset printing. The light intensity reference level in comparator 65 is variable in dependence on the speed of a printing web 12 measured by a tachometer 20, and the web speed is reduced if the intensity falls. The intensity is also automatically increased if a densitometer device 36 detects smudging of ink by a roller 32 indicating insufficient curing. |
