Centre National De La Recherche Scientifique

UniversitÉ De Poitiers

Socpra Sciences Et Genie S.e.c.

Abzac Canada Inc.

Alain Berry

Patrice Masson

Pierre-Michel D'Anglade

Yves Gervais

Nicolas Quaegebeur

Cédric Ardin

Anthony Gerard

Michel Besombes

An in-line, contactless and non-destructive method for detecting and identifying defects in a moving cardboard structure is provided, as well as the associated system. The cardboard structure is of the type made of layered paper plies, such as cardboard tubes for example. The method includes the steps of emitting acoustic waves with predetermined frequencies toward the moving cardboard structure. The acoustic waves are converted into mechanical waves propagating through the moving cardboard structure. The method also includes a step of capturing the acoustic waves propagated, wherein said captured acoustic waves result from a conversion of the propagated mechanical waves through the moving cardboard structure. The method also provides steps of analyzing the captured acoustic waves; and detecting and identifying defects in the moving laminated cardboard structure based on predetermined propagation properties measured from the captured acoustic waves.

In-line, contactless and non-destructive method and system for detecting defects in a moving cardboard structure

A method and apparatus for reducing a selected tonal noise generated by a fan operating in a non-uniform flow by locating at least one obstruction in the non-uniform flow such that the at least one obstruction generates a noise that is out of phase with the selected tonal noise. The noise generated by the at least one obstruction interferes with the selected tonal noise, thus reducing the selected tonal noise. It is also contemplated to use additional obstructions to reduce other tonal noises generated by the fan.

Method and apparatus for controlling tonal noise from subsonic fans

Growing community of inventors

Sherbrooke, Canada

Alain Berry