摘要 |
Flat articles, in particular printed circuit boards, coated with a curable material, repose at their edges upon two belt conveyors which are positioned at an inclination. By means of these belt or band conveyors, the printed circuit boards are fed, in a predetermined conveying direction, below a heating device containing at least one hot air infeed device. The surface or face of the printed circuit board confronting such hot air infeed device is therefore subjected to the action of the hot or heated air, resulting in curing or hardening of the applied material layer. At the opposite side of the printed circuit board, facing away from the hot air infeed device, there is arranged a collecting tube or pipe which extends in the conveying direction. This collecting tube is provided with outlet openings for cooling air. Hence, the lower face of the printed circuit board has applied thereto the cooling air. In this way there is prevented that the layer of applied material which has already cured and located at the bottom face or side of the printed circuit board will again be exposed to thermal action, which undesirably could result in further undesired curing of such material layer.
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