Method and apparatus for the continuous monitoring and control of cell size in a foam structure
US3953739A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1974 |
| Grant date | Apr 27, 1976 |
| Priority date | — |
| Expiry date | Sep 30, 1994 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C44/507
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus are provided to continuously monitor and measure the average size of individual foam cells contained in a foam structure, such as polystyrene foam for example, as it is being fabricated. Such an arrangement permits the prompt adjustment of process conditions and/or the concentration of nucleating agents in the extrusion system in the event the foam cell size deviates from a preselected norm. The method comprises illuminating the surface of a foam sheet, receiving and collecting at least a portion of the light which is diffused and reflected from the foam sheet with a detector photocell, electrically measuring the amount of light energy received by the photocell and converting such measurements into a cell size measurement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.