Abstract: An improved apparatus and method provide conditioning to a powder deposited on a substrate (e.g., a web), for example, by wetting the powder in a 3D printing apparatus. To achieve this in an exemplary implementation, a wetting apparatus is located between a powder dispenser and at least one top calendering roller in a direction of movement of the substrate, wherein the wetting apparatus is configured to apply a wetting agent to the powder on the substrate before the powder passes through the calendering roller. The wetting agent is comprised of a material which increases cohesiveness of the powder to prevent the powder from adhering to the top roller. In a particular implementation, the wetting agent is steam confined to an area of the substrate where the powder passes through the wetting apparatus, without wetting other areas of the substrate which are not in the wetting apparatus.

Abstract: A device to permit manual adjustment of the track or path of a conveyor belt (1) while providing constant, predetermined belt tension. A removable conveyor roller (23) is supported by a pivotable yoke (11), which is pivoted about a shaft (12) from a nonoperational position of no belt tension, at which point cleaning and regular maintenance take place, to the operating position of full belt tension. Conveyor belt tension is provided by at least one spring (10), the spring force increasing with deflection during the pivoting motion of the roller yoke (11) into the normal operating position. The spring force resists the motion of a pivoting plate (8) to slide in a plane relative to the fixed conveyor bed (18) along an adjustable axis. Force is transmitted through the pivoting shaft (12) to the yoke (11) which creates tension in the conveyor belt (1) without exceeding the load limitations of the conveyor belt (1) or the roller shaft (9) bearings.