US3197182A - Dual homogenizer - Google Patents

Description

3y 7, E. F. HILL DUAL HOMO GENI Z ER Filed bee. 16, 1963 All INVENTOR. la- 4- Flflk l EDWARDFHILL BY ,/2' I United States Patent 3,197,182 DUAL HOMOGENIZER Edward F. Hill, 97 Winthrop Road, Hillsdale, NJ. Filed Dec. 16, 1963, Ser. No. 330,902 1 Claim. (Cl. 259-135) This application is a continuation-in-part of my co-pending application, Serial No. 69,417, filed November 15, 1960.

My invention relates to an improved blender or homogenizer for blending, mixing, and homogenizing solids and liquids.

The blender described in the earlier application employs a single mixing chamber in which the mixture to be blended is agitated by creating a turbulent flow through a multichannel stator, and after being expelled from the stator, the mixture strikes a movable bafile plate which redirects the heavier particles back into the mixing head. While exceptionally good results have been obtained, particularly in dispersing solids in liquids, I have found that better mixing action can be achieved if the movable baffle plate is replaced by a second mixing head, similar in construction to the first mixing chamber.

In accordance with my invention, I provide two mixing heads, or chambers on a common shaft. Each of these mixing heads comprises a stator portion which is divided into a plurality of sectors by vanes which extend between an outer casing and a sleeve in which the shaft is suitably journalled. Closely spaced from each stator is a relatively fiat propeller, or rotor, which is driven by the shaft.

Further, in accordance with my invention, the second, or upper mixing head is positioned so that its stator faces the stator of the lower mixing head. Consequently, the turbulent mixture flowing upwardly from the lower mixing head enters the stator of the upper head and is forced downwardly by the action of the propeller in the upper portion of the upper mixing head. In effect, therefore, the two mixing heads operate in tandem and, of course, greatly enhance the turbulence and mixing in the mixture. The invention will now be described with reference to the accompanying drawing in which:

FIG. 1 is an elevational view in section of the improved blender;

FIG. 2 is a top view of the mixing chamber assembly or mixing head;

FIG. 3 is a sectional view along the lines 33 of FIG. 2; and

FIG. 4 is a plan view of the propeller in each mixing chamber.

Referring to FIG. 1, the improved blender, according to the invention, comprises a pair of mixing chambers 1 and 2, respectively, mounted on support rods 3, 4.

Each of the mixing chambers comprises a tubular casing 5 (see FIG. 2) the upper portion of which is divided into a plurality of chambers by radial partitions 6 which extend between the inner wall of the casing and a hollow sleeve or bushing 7 in which a shaft 8 is journalled for driving a propeller 9 housed in the lower part of the casing 10. Shaft 8 is driven by a motor 11 through a coupling 12.

As disclosed in my earlier copending application, the propeller in each mixing chamber comprises four blades 13 mounted on a hub which is locked to the shaft by a ice key and a set-screw counter-sunk to fit over the bushing. In order to insure full and complete agitation and homogenization of the mixture drawn into the chamber, each of these blades must be relatively flat, i.e. they form an angle not exceeding about 30 with the horizontal axis, and the propeller assembly must be positioned to clear the radial partitions, or stator vanes, with a minimum clearance, i.e. about 0.005 inch to insure shearing action.

When both mixing heads are submerged in the mixing bath, constituents are drawn into lower head 1 by the propeller in the lower portion of the casing and forced into the chambers formed by the stator vanes 6. Due to the small pitch of the propeller blades, extensive shearing action in the material drawn upward by the action of the propeller occurs, which action on the material of the bath is further enhanced by the turbulence created in the stator chambers. Upon being expelled outwardly from the first mixing chamber or head 1, i.e. moved upwardly from the stator chambers, the material already in a state of dispersion is carried upwardly into mixing chamber 2 which is positioned with its stator vanes in the lower portion, or facing downwardly toward the stator vanes in head 1. There the material is caused to reverse direction because the propeller, now in the upper part of head 2 forces the mixture back into the stator of head 2.

The combined actions of the two mixing heads forcing the mixture into a violent state of agitation fully disperses the solids into the liquid. Due to the combined action of the propellers, which shear the mixture breaking up heavier components, the turbulence created by the stator vanes, and the back-to-back action of the two heads, solids are effectively broken up and brought into a fine state of dispersion.

Consequently, the improved mixer, or blender, according to the invention, can blend mixtures which include difficultly dispersable aggregates and insures uniform blending and homogenization of the components. It may be employed to disperse heavy pigments in a vehicle. It may be employed in pulp manufacture. In fact, it will mix almost any fluid constituents which are capable of being blended together.

Therefore, while I have described my invention with a particular embodiment and specific applications theerof, it will be understood that other modifications therein will be apparent to those skilled in this art without departing from the spirit and scope of the invention which is defined in the appended claim.

What I claim is:

A mixing device comprising first and second mixing heads, each of said mixing heads comprising a first tubular member, a second tubular member within and coaxial with said first tubular member, said second tubular member extending from one end partially within said first tubular member, a plurality of radial vanes extending between said first and second tubular members dividing the space between the first and second tubular members into a plurality of channels, said first and second tubular members and said radial vanes constituting a stator portion for each mixing head and dividing each of said mixing heads transversely into two sections, a propeller in the other section of each of said heads, said propeller comprising a plurality of blades extending substantially parallel to the adjoining surface of said stator and being spaced therefrom by a Patented July 27, 1965 distance of about 0.005 inch throughout the entire surface References Cited by the Examiner thereof, the blades of each of said propellers forming an UNITED STATES PATENTS angle with an axis perpendicular to its axis of rotation which is less than about 30, said other section being 1,794,214 2/31 Thurm et a1 259 9Z otherwise completely unobstructed, support means for po- 5 2,357,640 9/44 Eppsnbach 259 105 k sitioning both of said mixing heads in spaced relationship FQREIGN PATENTS with their stator portions opposing one another, and means 777 271 6/57 Great Britah for driving said propellers simultaneously whereby the 1 portion of the mixture moving from one of said mixing NALTER SCHEEL, Primary Examiner heads to the other of said mixing heads is reversed in the 10 direction of its movement by the latter mixing head. JILLIAM PRICE, Examiner-

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