David Lawrence Jenson

US Patent:

40895092, May 16, 1978

Filed:

Jul 5, 1977

Appl. No.:

5/813067

Inventors:

James L. Morton - Eden Prarie MN
Thomas H. Birchell - Livermore CA
James M. Noble - Alamo CA
David W. Jenson - Lafayette CA

Assignee:

Seltec Corporation - Fremont CA

International Classification:

B28C 704

US Classification:

366 8

Abstract:

A system for preparing asphalt mix of a selected composition is disclosed wherein the correct proportions of various grades of aggregate to be mixed with liquid asphalt are maintained by repeatedly measuring the weight of aggregate contribution from each of a plurality of feed bins containing different grades of aggregate, comparing the proportion of the total aggregate from all of the feed bins contributed by each individual feed bin to a preselected desired proportion for the particular grade of aggregate contained in that feed bin, and responsive to said comparison, adjusting the rate of feeding of aggregate from that feed bin to correct the actual proportion of the total agregate from that feed bin to the preselected desired proportion. The comparison and adjustment steps are repeated at a selected interval and the proportions of aggregate from each bin are determined based on the average output of each bin over the same interval. If an upward adjustment beyond the feed rate capacity of a particular feed bin is required, the output of the remaining feed bins is proportionately reduced until the maximum output of the particular feed bin provides a proportion of the total output of aggregate consistent with the desired composition of the asphalt mix.