US1353165A

US1353165A - Mixer

Info

Publication number: US1353165A
Application number: US278467A
Authority: US
Inventors: Johnson John
Original assignee: Individual
Current assignee: Individual
Priority date: 1919-02-21
Filing date: 1919-02-21
Publication date: 1920-09-21
Anticipated expiration: 1937-09-21

Description

J. JOHNSON.

MIXER.

APPLICATION FILED FEB. 21, 1919.,

1,353,165, PatentedSept. 21, 1920.

UNITED STATES PATENT i orrice.

JOHN .ronnson; or 300mm, NEW YORK mrxm Continuation of application Serial No. 102,110, fl1ed June 7, 1916. Renewed Februaryzl, 1919, serial No. 278,509. -This applicationfiled February 21, 1919. Serial No. 278,467.

To all whom z't may concern.

Be it known that I, JOHN JOHNSON, -a

citizen of 'the'United States, residing at Brooklyn, New York, have invented cer tain new and useful Improvements in Mixers, of which the following is a clear, full and exact description.

My'invention relates to mixers and particularly to rotary mixers for use in mixing solids, liquids or gases, with liquids, and is a continuation of m application Serial No. 102,110, filed June th, 1916, renewed Feb. 21, 1919, Serial No.v278,509, as to common subject-matter. V

Rotary mixers as hitherto constructed have usually tended in operation to impart to the contents of the mixing tank a whirling motion about the axis of rotation, this whirling motion with its resulting eddying effect tending to interfere with those movements of the liquid across the axis of rotation, and lengthwise thereof, which are necessary for thecomplete intermingling of the materials .to be mixed. Moreover, in-the operationof rotary mixers or mixing Wheels of'the tangential type, the centrifugal flow of the liquid through the wheel tends also to create an eddy in the stream entering the central part of the wheel, and this eddying movement of course reduces the stream to the wheel and, consequently, the mixing action of the wheel. part due to the fact that the material is not brought to the opening leading to the centrifugal wheel with sufiicientvelocity to feed the wheel as fast as the wheel can de liver the material.

An object'of the invention is to provide simple and efiicient mixin means which will obviate the difficulties heretofore experienced in mixing operations, and will insure effective intermixing of the contents of the mixing tank. Y

More particularly the invention aims to provide improved mixing means of themtary type which will operate to insure movement of the liquid across the axis of rotation as well as lengthwise thereof, and at the same time will check any tendency to bodily whirlingi of the tank contents about the axis of rotation. v

An important feature of the invention is the arrangement. in the stream to the centrifugal .wheel, of means for imposing upon the stream a centripetal tendency.

Specification of Letters Patent.

This eddying is in Patented Sept.-2,1,- 1920.

Another important feature of the invent1on is the provlslon of means about the periphery of the rotary mixer or turbine wheel for converting the tangential movement of the discharged material into sub-. stantially a radial movement. Another important feature of the inventlon is the provision of a member located adjacent to the centrifugal wheel and so formedas to increase the-flow of material to said wheel and thereby prevent eddiesin the stream above said member.

' Other objects and important features of the invention will appear from the followdescription and claims when considered In connect1on,w1th the accompanying draw in s in whichigure 1 is a vertical elevation of the m1x 1ng device, the tank in which the mixing devlceis located being shown in secton;

Fig. 3 is a section on the line- 33 Fig. 2; and

Fig. 4 is a section on the line 4'-4 Fig.2.

' 7 5 Fig. 2 is a plan of the device Referring to thedrawings, 2 represents a centrifugal mixer situated at the bottom of the mixing tank 4, the mixer being driven by any suitable means such as .a shaft 6 connected b gearing 8 and 10 to a power shaft 12. he mixer comprises a series of turbine blades 14 supported and carried by a ring 16, the blades 14 being arranged around the central opening in the ring. These blades 14 are inclined away from the direction of rotation of the {wheel 0 mixer 2.

When the mixer is rotated-rapidly, the blades14 tend to" create a centrifugal flow v 1 to 3. These blades bend forwardly in the direction of rotation-of the centripetal member and also bend downwardly, the forward inclination increasing from the hub' 18 of the member, toward the extremities of the blades. 16 tends tocreate a centrlpetal tendency 1n the stream, which serves to increase the To counteract .these" Thus formed, themember amount of fluid delivered to the opening of'the centrifugal wheel 2.

Thecentripetal member 16 and the centrifugal wheel 2 may be, and preferably are, cast in one piece as shown in Fig. 3. i As the mixed materials are discharged from the periphery of the centrifugal wheel 2, they tend to travel in tangential paths across the bottom of the mixing tank 4, and then to flow up the side of the tank to a position above the wheel to replace the material drawn into the center of the wheel. The tendency of the wheel is gradually to set up a whirling motion of the entire contents of the tank in the same direction as the rotation of the wheel. This whirling motion with its accompanying eddying effect tends to counteract the mixing action of the wheel and to throw the entire tank contents, by

centrifugal action, to the outer wall of the tank out of range of the operation 'of the wheel.- In order to prevent this tendency and to insure a positive mixing of the materials and a proper direction of the mixing currents, I provide a series of stationary bafile plates 20, which are preferably so 10- 'cated about the periphery of the wheel 2 and at such angles to the periphery that they intersect" the tangentially moving materials and tend to direct them along radial lines as shown in Fig. 2 of thedrawing. These baffle plates may conveniently be formed upon segmental plates 22, which can be attached by screws 24 to the bottom of the tank, four of these baffle-carrying segment plates being shown. It will be especially noted that the baffle plates 20 are located close to andoutside of the path of rotation of the blades 14 of the centrifugal wheel 2 and are curved gradually into intersecting relation to the tangents to the peripheral path of the blades 14; This particular shape of the blades 20 gives a very eflicient action to the mixer which is not the case when the blades are straight, as has been heretofore suggested.

Having thus described my invention, what'I claim and desire to secure by Letters Patent is:

1. A rotary mixer comprising a rotary body having a central opening, means for establishing a centrifugal flow of material entering said opening, and means interposed in the stream to said opening action to im pose upon said stream, as it enters said opening, a centripetal tendency.

2. A rotary mixer comprising a rotary body -having a central opening, means traveling with said rotary body for establishing' a centrifugal flow of material entering said opening, and means located at spaced points about and outside the peripheral part of the path of rotation of said body and curved gradually into intersecting relation to the tangents thereto, for checking the tangential movement of material discharged from said rotary body.

3. A rotary mixer comprising a rotary body having a central opening, blades carried by said body outside said opening and lying transverse to but curved away from the direction of rotation of said body, other blades located along the axis of rotation with respect to said first-mentioned blades but curved in the direction of turning and projecting over said central opening whereby said last-mentioned blades exert a centripetal pull upon material drawn into saidopening bythe centrifugal flow created by said first-mentioned blades, and said centripetal blades being feathered to pull the material along the axis toward said opening.

4. A rotary mixer comprising a rotary body having a central opening, blades carried by said body outside said opening and lying transverse to but curved away from the direction of rotation of said body, other blades located along the axis of rotation with respect to said first-mentioned blades but curved in the direction of turning and located above and projecting over said central opening whereby said last-mentioned rial drawn into said opening bythe centrifugal flow created by said first-mentioned blades. I

5. A rotary mixer comprising a rotary body having a central receiving opening, means for establishing a centrifugal flow of the material received through said opening,

and means for preventing eddies in the stream of material, said means comprising a member situated adjacent to said opening bladesexert a centripetal pull upon matetrifugal flow of material thereby creating a downward stream in the material, and means for preventing eddies in said stream, said means interposed in the downward stream of material adjacent said rotary body and acting to create a centripetal tendency in saidstream.. i

Signed at Brooklyn, N. Y., this 9th day of January, 1919.

I JOHN JOHNSON. Witnesses:

DANIEL O. MIoHEL, MARY E. MICHEL.