Method and apparatus for determining the binder content in a fibrous mat

Abstract

A method and apparatus are disclosed for measuring the amount of binder or of a particular constituent of that binder dispersed within a fibrous mat. The binder may typically be a suspension of one or more solids in a liquid carrier such as water. A radiation source is provided at a first wave length which is highly responsive to the presence of the binder constituent dispersed within the mat. A second radiation source is provided at a second wave length which is substantially insensitive to the presence of the binder constituent within the mat. A ratio is taken of the transmitted energy at these two wave lengths through the mat and this ratio is used as an indication of the amount of the binder constituent. A third source of radiation and a third wave length is transmitted through the mat to provide an indication of the thickness or density of the mat, the third wave length being substantially unaffected by the presence of the binder constituent in the mat. This measured density is factored with the measured values of the binder taken from the transmitted energy levels at the first and second wave lengths to correct these measurements for the effect of the mat. As an alternative, the first and second wave lengths can be chosen to measure change in state of a binder constituent, such as a suspended solid, during cure.

Dependencies are inferred from the claim text.