The concept of mixing materials by utilizing "static" or motionless mixing has been known for sometime. In the past 4 years, two designs have been available on the market one of which consists of a series of helical elements in a tube or pipe, and the other of which utilizes a complex series of tubular channels. Both of these structures divide and recombine a stream in geometric progression, and within a relatively short distance, feed stock material is thoroughly and predictably mixed. ("Automation", February 1972 "Motionless Mixers"). The helical element type of device is clearly disclosed in U.S. Pat. No. 3,286,992 to Armeniades et al. dated Nov. 22, 1966. These devices are called motionless mixers because they have no moving parts. Relative movement of the fluid with respect to the motionless mixing elements is, however, achieved by the flow of fluid within the conduit.
Other efforts at blending various materials include the patent to Heyl et al. No. 2,601,018 wherein the blending tube contains a single perforated sheet metal spiral member substantially throughout its length, the perforated surface of the spiral member extending from wall to wall of the blending tube. Rogers in U.S. Pat. No. 2,628,864 is disclosing an aerosol paint spraying device taught the use within the spray tube of a spiral form member formed either of twisted wire or a helical ribbon of metal. Andrews et al. in U.S. Pat. No. 2,710,250 taught the mixing of fluids with a series of orifice members in a conduit. Grubb et al. U.S. Pat. No. 2,863,649 taught an apparatus for mixing on a small scale of compositions having a short period of coexistence when mixed and utilizing a rotating mixing rod having a small wire spirally wound around it and including at regularly spaced intervals spiral notches. Another device is taught in the patent to Thomas et al. U.S. Pat. No. 3,089,683 wherein an elongated tubular body is provided with a series of diffusers which create a turbulent flow of the liquids thereby ensuring a complete mixture of the liquids prior to ejection through the outlet. U.S. Pat. No. 3,203,371 to Mosey teaches a machine for whipping of confectionary filling utilizing in the nozzle thereof a baffle which comprises a strip of chrome steel twisted into a helical form and having a plurality of transverse slits to provide a multplicity of teeth or tongues which extend more or less radially from the axis of the helical bent strip.
The present invention is distinguished from these prior art devices in that the motionless mixing element is a singular structure of far simpler geometric configuration then that heretofore proposed and therefore much less costly in either fabrication or disassembly and cleaning than prior art structures.