US3062513A - Mixing apparatus - Google Patents

Description

Nov. 6, 1962 A. KEPES 3,062,513

' MIXING APPARATUS Filed Oct. 23, 1958 2 Sheets-Sheet 2 INVENTOR.

ANDRE KEPES q- 4 15M Mfi/fwu A TTO United States Patent Ofifice 3,052,513 Patented Nov. 6, 1962 3,062,513 MIXING APPARATUS Andr Kepes, Saint Mantle, France, assignor to Compagnie de Saint-Gobain, Paris, France Filed Oct. 23, 1958, Ser. No. 769,23 Claims priority, application France Oct. 29, 1957 16 Claims. ((11. 259-101) This invention relates to a mixing apparatus, and more particularly relates to an apparatus which mixes and homogenizes a wide variety of materials such as viscous or plastic liquids, with or without included finely divided solid materials, by a shearing action.

The invention has among its objects the provision of a novel improved mixing apparatus.

A further object of the invention resides in the provision of a novel mixing apparatus which functions to throttle and shear the material being treated, whereby to mix and homogenize such material in a rapid and eflicient manner.

Still a further object of the invention lies in the provision of a simple, rugged, and easily operated mixing apparatus, a preferred embodiment of such apparatus incorporating means for adjusting the throttling and shearing action of the apparatus.

Still another object of the invention lies in the provision of an improved mixing apparatus of the type described Which may be quickly and easily filled with material to be mixed and, at the end of the treatment of the material, may be easily emptied of such material.

Yet another object of the invention resides in the provision of an improved simplified means for driving the agitating and pressure-producing vane f the apparatus, such means in preferred embodiments incorporating a safety device to prevent damage to the mechanism, should the vane become jammed.

The above and further objects and novel features of the invention will more fully appear from the following description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only and are not intended as a definition of the limits of the invention.

In the drawings, wherein like reference characters refer to like parts throughout the several views,

FIG. 1 is a View in vertical transverse section through an illustrative embodiment of the main body portion of the mixing apparatus of the invention;

FIG. 2 is a view in longitudinal axial section through such main body portion, the section being taken along the line 22 of FIG. 1;

FIG. 3 is a view in longitudinal section similar to FIG. 2, but with the adjustable member of the material throttling and shearing means advanced into closed position between the two compartments of the apparatus; and

FIG. 4 is a diagrammatic view showing the driving means for the agitating and pressure producing vane of the apparatus.

As indicated above, the apparatus of the invention is adapted for the mixing of various materials, including those which are liquid, viscous, or plastic. Thus, the apparatus may be employed for the mixing of different plastic materials together, either with or without solvents or plasticizers, and for the homogenization of mixtures of plastic materials which are ordinarily considered to be incompatible. In some instances, such homogenized mixtures of plastic materials have properties never heretofore attained because it was not previously possible to homogenize them sufiiciently. The apparatus may also be employed to advantage for the incorporation of pigments in paints and the like.

Generally, the mixing apparatus in accordance with the invention, includes a closed receptacle or housing, there being a vane pivotally mounted in the housing in such manner that it has sealing engagement with the inner walls of the housing. The vane is so arranged relative to the housing as to divide the later into two compartments of variable voulme communicating with each other, the volume of one compartment increasing as the other decreases, and vice versa. Communication between the two compartments is provided by one or more orifices which submit the material to a throttling and shearing action as it is forced from one compartment to the other.

The apparatus includes accessory mechanism such as inlet valves and valves through which the treated material may be ejected, means for driving the apparatus in cluding a driving train in which there is interposed a safety mechanism to prevent damage to the mixing apparatus and/ or to the driving means.

Turning now to the drawings, FIGS. 1, 2, and 3 depict an illustrative embodiment of the main or mixing portion of the apparatus. The apparatus has a housing including a semi-cylindrical portion 22, having opposed spaced parallel plate members 21, 21a, sealingly secured to its ends. The housing is completed by a cover plate 31 which is secured and sealed to members 21, 21a, and 22. Cover plate 31 has an orifice 33 therein, through which material to be treated is charged into the space within the housing. Opening 33 may be closed by a plug 30 having a lower end of smaller diameter lying with its inner end flush with the inner surface of plate 31. When fully inserted in the orifice 33, the lower end of the larger outer portion of plug 30 engages a shoulder 33a in plate 31, the plug is held in inserted position by a bayonet-fastening means, which is somewhat generally shown.

Centrally of cover plate 31 and extending longitudinally thereof, there is a vertical slot 34 of appreciable width. A vertically reciprocable block 28 in the form of a parallelepiped sealingly engages the walls of the slot in the cover and the upper inner walls of end members 21, 21a. Block 28 may be adjusted vertically from a position in which its lower edge lies flush with the lower surface of cover plate 31 (FIG. 3) to a position in which it is appreciably raised thereabove (FIGS. 1 and 2). In the em-- bodiment shown, the adjusting means takes the form of a shaft having an eccentric central portion 29 lying between plates 21, 21a, the ends of the shaft being journalled in such plates, and an eccentric follower connected to the upper end of block 28. The follower has upper and lower inner surfaces which lie above and below and closely engage eccentric portion 29 of the shaft. The shaft may be turned as desired to adjust block 28 by means of the handle 29a.

Journalled axially within portion 22 of the housing, there is a circular cylindrical cross shaft 32 which is so positioned that its upper surface lies fiush with the inner lower surface of cover plate 31. Projecting radially from shaft 32 within the housing is a vane or blade 24, the opposite main surfaces of which lie tangent to the surfaces of shaft 32 and converge somewhat in a radially outward direction. As a result, when shaft 32 and blade 24 are in the position of FIG. 1, the surface 24a of the blade closely engages the lower inner surface of cover plate 31 (and of plug 3%) and that when shaft 32 lies in its other terminal position, after it has been turned counterclockwise from the position of PEG. 1, the surface 24b of the vane or blade 24 engages the lower inner surface of'the cover plate 31 at the right (FIG. 1). The vane 24 has a material-tight running engagement with the inner circular wall 22a and the inner surfaces of members 21 and 21a.

Cover plate 31 is provided at the right thereof (FIG.

3 1) with a horizontal bore 35 extending a substantial distance thereinto in a direction transverse to the central longitudinal plane of the covered plate. A cylindrical tubular valve member 26 is tightly but rotatably mounted within bore 35. The cover plate is provided with an orifice 36 which communicates with a similar orifice 36a in valve member 26 when the latter is turned into the open position shown in FIG. 1 by the valve operating handle 27. In such position of the valve, the contents of the apparatus may be forced outwardly by vane 24 through the outer end of valve member 26 in a manner to be explained. During the mixing operation, the valve is closed by being turned to present an imperforate wall portion opposite opening 36.

The apparatus of FIGS. 1, 2, and 3, may be filled with material by removing the plug 36, opening the valve 25, and pouring the material into orifice 33 while slowly rotating vane 24 counterclockwise to aid in the feeding in of the material. When the housing has been filled with material to the extent desired, valve 26 is closed and plug 33 is inserted and sealed in position. The driving means for oscillating vane 24, to be described, is now placed in operation, the block 28 usually being initially adjusted into its upper position shown in MG. 1. The material being treated is progressively driven in reverse directions from one compartment to the other through the orifice 28a presented between the circular cylindrical surface 32a of shaft 32 and the lower end surface of block 28. In its travel through such orifice, the material is subjected to a throttling and shearing action which rapidly mixes and homogenizes it. As the treatment of the material progresses, block 28 may be successively adjusted downwardly to decrease the cross section of orifice 28a, and to increase such throttling and shearing action.

Depending upon the material being treated, the housing may be heated or cooled as required. A number of parallel bores 23 extending through members 21 and 22 may contain either electric resistance heating units or alternatively may be connected to a source of heating or cooling fluid circulated through the housing to maintain the material being treated at the desired temperature.

After the material has been fully mixed and/ or homogenized, the driving mechanism for vane 24 is shut off. With the vane in the position of FIG. 1, block 28 is adjusted downwardly into contact with surface 32a of shaft 32, and valve 26 is opened. The vane 24 may be then slowly driven in a counterclockwise direction so as to force the material in the housing downwardly through openings 36, 36a, and out the open end of valve 26.

In FIG. 4, there is shown somewhat diagrammatically the driving and safety mechanism for the illustrative preferred apparatus. An electrical motor 16 having a pulley 17 on the shaft thereof is drivingly connected to a shaft 19 through the medium of a V -belt as indicated and trained over pulley 17 and a pulley 18 on shaft 19. The shaft 19 is journalled for a limited axial movement in bearings supported in fixed frame members Zita and 20b. A worm 2 affixed to shaft 19 meshes with a worm gear 3 which is a part of a speed reducing train composed of the worm 2, the worm gear 3, and spur gears 3a, 3b, and 30. Gear 3c, as indicated in FIG. 4, is aifixed to shaft 32 which carries the blade or vane 24.

Mounted on a fixed frame structure at the end of shaft 19, and extending transversely of shaft 19, are two generally somewhat parallel arms 6 and 7 which are pivotally mounted on pins 4 and 5 affixed to such frame part. The outer free end of shaft 19 extends freely through an opening in arm 6, there being an abutment member 8 affixed to shaft and lying between arms 6 and 7. Affixed to the fixed frame part which carries arms 6 and 7 is a fixed abutment 12 which lies between the outer free ends of the arms. When shaft 19 is in a central position, the arms 6 and 7 are resiliently retained in engagement with abutment 12 The means for thus retaining the arms is composed of an elongated bolt 11 which extends freely through openings in arms 6 and 7 and has a head 11a engaging the surface of arm 6. A coil compression spring 9, telescoped over the outer end of bolt 11, is held under a predetermined compression against the surface of arm 7 by a nut 10 on the bolt. The spring 9, acting through the other means described, tends to maintain shaft 19 in a central axial position.

Arms 6 and 7 have noses 13b and 13a, respectively, which cooperate with a tumbler 14 of a reversing switch 15 which is interposed in the feed circuit for motor 16. The motor 16 runs in one direction when the tumbler 14 is in the counterclockwise position shown in FIG. 4, and runs in the other direction when the tumbler 14 is turned to its clockwise terminal position.

The driving mechanism of FIG. 4 operates as follows:

The coil compression spring 9 is held under such compression, that acting through bolt 11, arms 6 and 7 and abutment 8 maintains shaft 19 against appreciable endwise travel when vane 24 encounters only the usual resistance to its travel and, under such conditions, is in any position intermediate its terminal positions. When, however, the vane 24 comes into engagement with cover plate 31, at either end of its operative stroke, the worm 2 tends to climb on worm gear 3 and thus to thrust shaft 19 axially against the action of spring 9. Thus, for example, when vane 24 reaches one terminal position, shaft 19 is thrust to the right, so that abutment 8 forces arm 7 counterclockwise against the action of spring 9. Thereupon arm 7 is forced away from abutment 12, and nose 12a of arm 7 thrusts the tumbler 14 into its clockwise position, thereby to reverse motion 16 and to start the travel of vane 24 in the counterclockwise direction. Essentially the same action takes place when vane 24 reaches its other terminal position. In this instance, of course, abutment 8 retracts arm 6 from abutment 12, the nose 13b of arm 6 then forcing tumbler 14 into its counterclockwise position, shown in FIG. 4, thus again reversing the motor and the direction of driving of vane 24.

It will be apparent that not only does the mechanism described serve to drive vane 24 in reverse directions, but that it also serves as a safety mechanism. Thus, should the vane 24 become jammed in the housing in an intermediate position thereof, as by reason of the jamming of undesired solid material between the vane and the housing, the spring 9 will yield to allow the reversing of motion 16 before the imposition of a destructive torque upon the vane. Adjustment of nut 10 allows the mechanism to be preset to the torque at which such safety means will become effective.

Although only one embodiment of the invention has been illustrated in the accompanying drawings and described in the foregoing specification, it is to be expressly understood that various changes, such as in the relative dimensions of the parts, materials used, and the like, as well as the suggested manner of use of the apparatus of the invention, may be made therein without departing from the spirit and scope of the invention as will now be apparent to those skilled in the art.

What is claimed is:

1. Material mixing apparatus which comprises a closed housing having flat sides, a cover and an inner wall in the form of a surface of revolution the axi of which is adjacent the cover, a vane mounted in the housing for oscillation about the axis of said surface of revolution, a slot in the cover adjacent to and over the axis of the vane, forming a passage above the vane, means for oscillating the vane, the vane sealingly cooperating with the inner wall of the surface of revolution and the sides thereof to divide the space within the housing into two compartments each of which alternately increases and decreases in volume when the vane oscillates, and means to vary the cross-sectional area of the passage, the passage subjecting the material to throttling and shearing as it passes under pressure from one compartment to the other.

2. An apparatus as claimed in claim 1, comprising means selectively to close the first recited passage, a discharge passage connected to one compartment so that when the discharge passage is open the vane expels the contents of said compartment as the vane moves to decrease the volume of said compartment, and means selectively to open and close the discharge passage.

3. An apparatus as claimed in claim 2, wherein the space within the housing is in the shape of a sector of a cylinder, the housing includes a cover portion, and the first and second passages at least in part are located in the cover portion.

4. An apparatus as claimed in claim 1, comprising means to adjust the size of the throttling and shearing passage.

5. An apparatus as claimed in claim 1, wherein the passage is located adjacent the axis of oscillation of the vane, and wherein a portion of the passage-defining structure is formed by the portion of the vane adjacent its axis of oscillation.

6. An apparatus as claimed in claim 5, wherein the vane is mounted to project generally radially from a shaft having the remainder of its extent, within the housing, of cylindrical shape, there is a recess in the wall of the housing confronting said remainder of the extent of the shaft, and comprising means to vary the effective height of said recess with respect to the shaft.

7. An apparatus as claimed in claim 5, wherein the vane is mounted to project generally radially from a shaft having the remainder of its extent, within the housing, of cylindrical shape, there is an elongated slot located centrally of the housing and extending at least generally radially of the shaft, the inner end of the slot confronting said remainder of the extent of the shaft within the housing, and comprising a block in the slot defining, with the remainder of the shaft, said passage, and means to adjust the block toward and away from the shaft to vary the effective cross section of said passage.

8. An apparatus as claimed in claim 7, wherein the housing has parallel end walls, the slot spans the distance between the end walls, and the block has a length equal to, and sealingly fits within, the slot.

9. Material mixing apparatus which comprises a closed housing having an enclosing wall, the inner wall surface of the housing being in the form of a surface of revolution, a vane sealingly cooperating with the inner wall of the housing, means mounting the vane for oscillation in the housing, the vane dividing the space within the housing into two compartments each of which alternately increases and decreases in volume when the vane oscillates, a passage providing communication between the compartments, and means for oscillating the vane, said last named means comprising a reversible driving means, a drive train connecting the driving means to the vane to drive the latter, and means to reverse the driving means whenever the vane reaches one of its termini of oscillation,

the drive train including means which is yieldable upon the imposition of a predetermined load thereon, and means responsive to the yielding of the last named means to reverse said driving means.

10. An apparatus as claimed in claim 9, wherein the driving means is rotatable, the drive train includes a driven shaft capable of limited endwise motion, a worm on the shaft, a worm gear meshing with the worm, means drivingly connecting the worm gear and the vane, means resiliently opposing endwise motion of the shaft in either direction, and means responsive to endwise motion of the shaft during operation of the apparatus to reverse the driving means to drive the vane in the reverse direction.

11. An apparatus as claimed in claim 10, comprising speed reducing gearing between the Worm gear and the vane.

12. An apparatus as claimed in claim 10, wherein the driving means is a reversible electric motor, and wherein the means responsive to endwise motion of the shaft includes a reversing switch in circuit with the motor.

13. An apparatus as claimed in claim 12, comprising a pair of generally parallel pivoted arms disposed transverse to said shaft, a first abutment 011 the shaft lying between the arms, a second, fixed, abutment between the arms, resilient means constantly urging each arm toward the fixed abutment, and a tumbler means connected to the reversing switch and cooperating with said arms to throw the switch upon endwise motion of the shaft.

14. An apparatus as claimed in claim 13 wherein the resilient means is a spring, and the spring opposes movement of the shaft in either direction from a central driving position.

15. An apparatus as claimed in claim 14, comprising means for adjusting the force with which the spring urges the arms toward each other, and thus the force which is applied in opposition to endwise motion of the shaft.

16. Material mixing apparatus which comprises a closed housing having an enclosing wall, the inner wall surface of the housing being in the form of a surface of revolution, a vane mounted in the housing for oscillation about the axis of said surface of revolution, means for oscillating the vane, the vane sealingly cooperating with the inner wall of the housing to divide the space within the housing into two compartments each of which alternately increases and decreases in volume when the vane oscillates, and a passage of adjustable size over the vane including a slot and a movable block closing the upper part of the slot in the wall providing communication between the compartments in the housing, the passage subjecting substantially all the material to throttling and shearing under pressure in the passage at each swing of the vane.

References Cited in the file of this patent UNITED STATES PATENTS 602,492 White Apr. 19, 1898 FOREIGN PATENTS 267,681 Great Britain Mar. 24, 1927

Images