Patent ID: 8616761
Filing Date: 2013-12-31
Classification: G05D

Abstract:
1. A method for combining materials comprising at least one major material and at least one minor material, said at least one major material and at least one minor material combining to make a total, said method comprising the steps of: providing an apparatus, said apparatus comprising: at least one inlet for supplying at least one major material at a velocity; a plurality of inlet tubes for supplying a plurality of minor materials at a velocity; each said inlet for said at least one major material and each said inlet for each said minor material having a positive displacement pump associated therewith for supplying said respective major material or minor material, said pumps being driven by an associated motor and being operable independently of each other, each said inlet tube for said minor material terminating in an inlet tube discharge, each said discharge being in communication with a portion of said apparatus defining a confluence region, whereby said at least one major material and minor material can come together in a predetermined ratio within said confluence region; wherein at the confluence region there are: an inlet for supplying each said major material; an inlet tube discharge for supplying each said minor materials said inlet tube discharges being non-opposing and being in a common plane; and a common outlet for discharging said at least one major material and said at least one minor material combined together from said confluence region; wherein said inlet for supplying said major material comprises a conduit having side walls defining an interior therebetween, wherein said major material flows through said conduit in a direction, and said at least one inlet tube for supplying said minor material has an inlet end outside of said conduit and said tube passes through the side wall of said conduit and has a discharge end inside of said conduit to form a common discharge, and said apparatus comprising a motor control loop for said motor associated with said positive displacement pump, providing at least one major material; providing at least one minor material; supplying said at least one major material into said confluence region adding said at least one minor material to said confluence region in the vicinity of said major material, whereby said major material and said at least one minor material come into contacting relationship in a first proportion and are maintained within said confluence region; and changing the amount of said at least one major material and said at least one minor material added to said confluence region throughout a first period of time of less than one second by controlling their respective flow rates, while maintaining said first proportion of said at least one major material to a respective setpoint and said first proportion of said at least one minor material to a respective setpoint to provide said predetermined ratio of said major and minor materials; whereby no mix tank, flow control feedback loop or flow control valves are used for maintaining said predetermined ratio, wherein the accuracy of the predetermined ratio is maintained by controlling the energy to the motors associated with the pumps, rather than by the combination of a flow meter and a flow control valve, to match the velocity of the minor materials to the velocity of the major material to within an instantaneous error limit of about ±5%, thereby promoting better flow and mixing of said minor materials.