US2455177A

US2455177A - Mechanical mixing bowl

Info

Publication number: US2455177A
Application number: US697752A
Authority: US
Inventors: Russell E Irish
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-09-18
Filing date: 1946-09-18
Publication date: 1948-11-30
Anticipated expiration: 1965-11-30

Description

2 Sheets-Sheet 1 v R. E. IRISH -MECHANICAL MIXING BOWL w/mfi Jil n-INNER:

Nov. 30, 1948.

Filed Sept. 18, 1946 INVENTORv flusseZZE. Z *is h WM 22. 41%

M aflorwa Nov. 3%, 1948. R. E. IRISH I MECHANICAL MIXING BOWL 2 Sheets-Sheet 2 Filed Sept. 18, 1946 INV ENTOR Russell .E .l'rl'sh 5 44%, 3.61%

Patented Nov. 30, 1948 siren STATES PATENT orrics MECHANICAL MIXING BOWL Russell E. Irish, Pittsburgh, Pa.

Application September 18, 1946, Serial No. 697,752

12 Claims. 1

This invention relates to a mechanical mixing bowl. and particularly to a mechanical mixing bowl which has its greatest utility in the mixing and spatulation of dental investment material, in the mixin and spatulation of pharmaceutical preparations such as emulsions, pill masses, and in the mixing and smoothing of'fine plasters and enamels.

In uses such as those specifically named and in other uses of like sort,'it is highly desirable that the mechanical action be rapid and that its efiect on the material subjected to it be such as completely to eliminate air bubbles and to give a thoroughly mixed, smooth preparation of the desired consistency. It is, however, also highly desirable that the bowl itself be flexible in order to facilitate accurate pouring from it; that it be instantaneouslyremovablefrom the means which provide mechanical propulsion, to expedite pouring; that the bowl and the mechanical elements immediately associated w th it be susceptible of thorough and rapid cleansing, to prevent the material which has been prepared in the bowl from hardening therein or otherwise tending to cause deterioration of the bowl itself. or of its associ ated elements; and that the mechanical elements be so connected with the flexible bowl that leakage from the bowl is prevented.

In accordance with my invention I provide a mixing bowl possessing a conjunction of such desirable properties. Additionally, I provide an organization comprising power-actuated mechanical elements in which the agitator element is readily adjustable on and removable from its carrying element, and in which selected sizes and shapes of agitator are readily interchangeable to suit the specific material which is to be mixed in the bowl, the desiredconsistency of the mixed material and the amount ofspatulation which is desired.

In the accompanying drawings, illustrative of an apparatus embodiment of my invention:

Fig I is a view showing in elevation the casing for an electrical motor andthe mechanical elements associated with the flexible bowl of the assembly, the flexible bowl itself being shown in vertical section to expose its associated mechanical elements.

Fig. II is a plan view of the assembly shown in Fig. I.

Fig. III is a fragmentary vertical section on an enlarged scale, taken through'the lower region of the flexible bowl itself and through the con nections and mechanical operating means associated directly therewith, showing the shaft of the electrical motor from which propelling power is derived engaged with the mechanical operating elements within the bowl. Fig. IV is a bott-omplan view of'the inner of two retaining plates which engage the base of the flexible bowl between them. I

Fig. V is a vertical sectional detail View on a smaller scale taken through the agitator-carrying element of the assembly. Fig. VI is a vertical sectional view on the scaleof Fig. V, taken through the outer of the two re--'- taining plates and an agitator-mounting postv carried thereby. r '1. Figs. VII, VIII and IX of the drawings, all of which are assumed to be on the scale of Figs. III and IV, show three agitators of difierent sizes for application selectively to the same agitator-- carrying element. I

Referring to the drawings, reference'numeral l designates the casing of an electrical motor, to which leads electrical conductor 2 and which has switch operating means 3. As will appear, this motor has a vertical shaft cooperatively arranged with respect to the mechanical elements of the mixing bowl assembly to impart power actuation thereto.

The mixing bowl 4 itself, is composed of suitableflexible material, typically rubber, and the other elements of the assembly are formed and'arranged with respect to the bowl and the motor shaft and casing to give full benefit of the known properties of a flexible mixing bowl whilecombining those benefits with the advantages of power-actuated agitation. As shown, in base 5 of flexible bowl 4 is relatively flat and is engaged between an outer plate 6 and an inner plate "I. Each of these plates is provided with a set of three screw holes, the screw holes of which sets are designated respectively 8 and 9 and are ar; ranged to register with each ,otherand withholes' through the base of the bowl. When screws iii are inserted from within the bowl and the screws are run down, plates 6 and l clamp base 5} of the bowl between them. Desirably the firmness of this engagement is increased by roughening the; under face of inner plate 1, as by the circular" ridges ll shown most clearly in Figs. III and IV [3, which is open at both ends and into which: vertical motor shaft It substantially extends.

This tubular post i3 projects through a central opening IS in the inner plate I andthrough a matching central Opening in the base of the bowl and reaches upwardly in the interior of the bowl a substantial distance, which as shown brings its upper end approximately even with the upper edge of the bowl. The bowl 4 being composed of suitable flexible material, such as rubber, its engagement between plates 5 and I and around tubular post 13 makes a liquid-tight seal at the base, of the bowl, and the upward extension of integrally-mounted tubular post l3 continues that liquid-tight feature upwardly and interiorly of the bowl.

The agitator assembly is carried by tubular post [3 in cooperative engagement with the motor shaft. This assembly comprises an agitatorcarrying element, a motor shaft-engaging element and a bladed agitator. The agitator-carrying element is shown as a sleeve l6, which extends downwardly along tubular post is into the lower region within the bowl. At its upper end sleeve 16 is closed, as by a cap or plug II, and depending interiorly from the upper end of the cap or plug I"! there is an actuating rod l8. Between rod [8 and the interior of sleeve Hi there is an annular space l9, best seen in Fig. V, which is of suflicient width to receive tubular post [3.

In assembly, as shown in Fig. III, sleeve 16 is placed on post [3 with the post inserted in annular space 18 and is allowed to move downwardly thereover, until cap or plug ll of the sleeve rests on the upper end, of the post. As so positioned rod l8 extends downwardly within post [3 to make engagement with motor shaft l4. Such engagement is removably made by means of a. kerf 20 in the upper end of the motor shaft and a spline 2| at the lower end of actuating rod l8.

With flexible bowl 4 and its operating element removably placed on motor casing I and with operating rod l8 engaged with motor shaft 14, actuation of the motor shaft, rotates agitatorcarrying sleeve 16 on tubular post l3. The agitator proper, which may be assumed to be of the size shown in Figs III and VII, comprises a collar 22 adapted to embrace sleeve [6, a setscrew 23 passed through the collar to bear against the sleeve and a plurality of angularly set blades 24. Engagement of the agitator with its carrying sleeve'by means of the collar and set-screw permits adjustment of the agitator at different vertical levels therealong, and renders it readily mountable on and removable from the sleeve. For different materials acted on in the bowl, it is therefore a simple matter to replace an agitator of one size with a larger or smaller agitator of a size particularly suitedto the work which is to be done. Thus in Figs. VIII and IX I show agitators having respectively blades 24a and 24b which are progressively smaller than the blades 24 of the agitator shown in Fig. VII. Collars 22a and 22b of the agitators shown respectively in Figs. VIII and IX are, however, of the same bore diameter as the collar 22 of the agitator shown in Fig. VII and are equipped with similar set-screws 23a and 232). Since the desired effect usually is a smoothing action, exerted downwardly of the bowl without splashing, the inclination of the agitator blades with respect to the direction of rotation of the motor is such as to press the material being agitated downwardly in the bowl and fixed means are provided to intensify the action. Such fixed means, which cooperate to increase the effect of the agitator blades, is shown as up-startin vanes 25 extended radially of and beyond inte- 4 rior plate I and desirably made integral therewith.

The removability of the mixing bowl assembly from its operative mounted position of the motor casing, conjointly with the flexibility of the bowl itself contributes greatly to the utility of the organization. The mounting of the mixing bowl assembly is such as to hold it against the torque of the motor shaft withoutretarding its removal from the 'motor casing. For this purpose the shanks of screws ill which project beyond the outer plate 6 are smoothed to form positioning pins 25 which enter approximately placed holes in the upper wall 21 of motor casing I. This provides engagement against turning movement under the torque of the motor shaft, without preventing the bowl assembly being lifted from the motor casing.

To describe in detail a complete service use of the mixing bowl assembly, the bowl is placed in the motor casing in such position that pins 26 enter their receiving holes in upper wall 21 of the motor casing and motor shaft l4 extends upwardly into tubular post l3. The agitator assembly is mounted on post I3 either before or after positioning of the bowl, and it is a simple matter to bring spline 2i on rod I8 into registering engagement with kerf 20 of the motor shaft. The mixing action is then performed with spatulating effect on the material in the bowl; it being possible to introduce all ingredients at once, or to add finely divided solid material, such as the material for dental investment gradually and without splashing to liquid in the bowl.

When the mixing has been completed, the bowl assembly is lifted from the motor casing, and it is to be noted that it can be removed instantly and without operating any fastening means, merely by a straight lifting action. The agitator assembly is lifted from tubular post 13, again without loosening any fastening means, and can be set aside for cleansing.

The bowl is then in condition to pour its contents, and because of its flexibility the bowl can be distorted to any desired extent to give a pouring lip of a shape suitable for finely directing or distributing the contents of the bowl. In this pouring, the substantial upward extent of tubular post 13 prevents the escape of slurry from the bowl by way of the post, and the firmly clamped engagement of the bowls base between the retaining plates prevents the opening of any avenue of leakage as the body of the bowl is distorted.

The facility and speed with which the bowl can be lifted should be emphasized, because it permits the pouring to be done before the contents of the bowl can begin undesirably to thicken and at an instant properly timed'with respect to other incidents of the particular operation which is in progress. Also the flexibility of the bowl provides for finely directed pouring with one hand, leaving the other hand free for other operations on the work. It is understood of course that the advantages of a flexible bowl have in themselves been obtained by flexible bowls as previously known. It is to be borne in mind, however, that the mixing bowl assembly of my invention combines those advantageswith the advantages of power-actuated agitation, and by mechanical means which transmit that actuation in optimum manner, which are proof against leakage, which are non-obstructive and which are themselves structurally simple.

After'pouring the contents of the bowl, the

bowl and its associated mechanical elements readily are cleansed, as by holding them'under a jet of water. In thecleansing, the bowl can be turned inside out, without obstruction by the retaining plates and the elements integrated with them, the more effectively to present the interior surface of the bowl itself and the surfaces of the tubular post and the fixed vanes to a cleansing jet.

The bowl proper of my mechanical mixing bowl assembly has been described as flexible and it has been indicated that it is composed of a suitable flexible material, typically rubber. It is to be understood of course that it may becomposed of any of the so-called synthetic rubbers, or other plastics which are rendered suitable by approaching rubber in endurance, chemical resistance and elastomeric properties. The retaining plates and the otherassociated mechanical elements typically are composed of any metal which is suitable in strength and rigidity, but most desirably are composed of a metal or alloy which additionally is resistant to abrasion, and chemical action, and which is of attractive appearancc.

The primary object of my-invention, as explained above, is to equip a flexible mixing bowl in satisfactory manner with means for producing power-actuation of an agitator within the bowl. Certain features involved in the embodimerit of my invention provide, however, meritorious improvement in the assembly even though the bowl itself be of rigid structure.

Having disclosed in detail one physical embodiment of my invention it is to be understood that I do not intend to limit myself to structural details as herein illustrated or described, but that my invention is to be assumed to embrace such changes and modifications as come within the scope of the claims appended hereto.

I claim as my invention:

1. In a mechanical mixing bowl assembly comprising an encased electrical motor having a vertical shaft, the combination of a flexible-bowl, two opposed plates arranged respectively inside and outside the said bowl and engaging the base of the bowl between them over a major proportion of the area of said base, a tubular agitator-mounting and motor shaft-receiving post extended upwardly from the base of said bowl, an agitator-carrying element rotatable on said tubular post and arranged to engage the motor shaft therewithin, and means on the outer of the two said plates arranged to position the said flexible bowl on the motor casing against the torque of the motor shaft.

2. In a mechanical mixing bowl assembly the combination of a flexible bowl, opposed inner and outer plates directly connected with each other through the base of the bowl and engaging the base of the bowl between them to form an integrated element of the bowl without preventing the said bowl from being turned inside-out for cleansing, and agitator-carrying and motor shaft-engaging means carried by one of said plates.

3. In a mechanical mixing bowl assembly the combination of a flexible bowl, and two opposed plates one of them having a tubular agitatormounting post integral therewith directly connected with each other through the base of the bowl and engaging the base of said flexible bowl between them over the major proportion of the area of said .base to form an integrated element of the bowl-without preventing the. saidbowl being turned inside-out for cleansing.

4. -In a 'mechanicalmixing bowl assembly the combination of a bowl, opposed inner and outer plates directly connected with each other and engaging thebase, of said bowl between them to form an integrated element of the bowl, a hollow motor shaft-receiving and agitator-mounting member extended upwardly from the base of the bowl, an agitatorecarrying and motor shaft-engaging element rotatable on and extended into said hollow member, an encased motor having a vertical shaft engageable with the agitator of said bowl, a plurality of vanes extended upwardly and horizontally from the upper face of said inner plate, and means on the outer of said plates arranged positively to position the bowl on the motor casing against the thrust of the motor shaft without obstructing lifting the bowl from the casing.

5. In a mechanical mixing bowl assembly the combination of a bowl, retaining plates positioned respectively inside and outside the base of said bowl'directly connected with each other and'engaging the said "base between them over the major proportion of the area of said base to form an integrated element of the bowl, a tubular motor shaft-receiving and agitator mounting member extended upwardly within the bowl from one of said plates, an agitator-carrying element rotatable on said upwardly extended member, a plura'lity' of vanes extended upwardly and horizontally from the upper face of said inner plate, an agitator on said agitator-receiving element having; blades arranged to force material downwardly in said bowl and againstsaid vanes and an electrical motor having a shaft engaged with said agitator-carrying element.

6. In a mechanical mixing bowl assembly the combination of a flexible bowl, retaining plates positioned respectively inside and outside, the base of said bowl directly connected with each other and engaging the said base between them over themajor proportion of the area of said base to form an'integrated element of the bowl, a tubular motor shaft-receiving and agitator-mounting member extended upwardly within the bowl from one of said plates, an electrical motor having a shaft extended into the said tubular member, an agitator-carrying sleeve rotatable on said tubular member and engaged with the motor shaft therein, and a bladed agitator having blades arranged to force material downwardly in the bowl mounted on said sleeve and vertically adjustable thereon.

7. In a mechanical mixing bowl assembly the combination of a flexible bowl, retaining plates positioned respectively inside and outside the base of said bowl directly connected with each other through the base of the bowl and engaging the said base between them from an integrated element of the bowl, a tubular motor shaft-receiving and agitator-mounting member extended upwardly within the bowl from one of said retaining plates, an encased motor having a shaft extended into said tubular member, an agitatorcarrying member rotatable on said tubular member and engaging the motor shaft therein, and means on said outer retaining plate arranged to engage the bowl with the casing of the motor against the torque of the motor shaft, without obstructing removal of the bowl from the motor casing.

8. In a mechanical mixing bowl assembly the combination of a flexible bowl, retaining plates positioned respectively inside and outside the base of said bowl directly connected with each other and engaging the base of the bowl between them to form anintegrated element of the bowl, a tubular motor shaft-receiving and agitator-mounting member extended upwardy within the bowl from one of said retaining plates, an encased motor having a shaft extended into said tubular memher, an agitator-carrying sleeve rotatable on said tubular member and engaging the motor shaft therein, a plurality of vanes extended upwardly and horizontally from the upper face of said inner retaining plate, a bladed agitator having blades arranged to force material downwardly in the bowl and against said vanes mounted on said sleeve and vertically adjustable thereon, and means on said outer retaining plate arranged to engage the bowl with the casing of the motor against the torque of the motor shaft without obstructing removal of the bowl from the motor casing.

9. In a mechanical mixing bowl assembly the combination of a flexible bowl, motor shaft-receiving and agitator-mounting opposed inner and outer retaining plates engaging the base of said flexible bowl in clamping engagement between them to introduce the shaft of an electrical motor in leak-proof manner thereinto and to maintain the base of the bowl leak-proof against distortion of the body of the bowl in pouring.

10. In a mechanical mixing bowl assembly the combination of a flexible bowl, opposed retaining plates placed respectively inside and outside the base of said bowl, and tightening screws extended through both said plates and through the base of the bowl between them to clamp the said base between the said retaining plates, the shanks of the said screws being extended beyond the said outer plate to provide positioning pins for engaging the bowl to the casing of an electrical motor without obstructing removal of the bowl therefrom.

11. In a mechanical mixing bowl assembly the combination of a flexible bowl, opposed retaining plates placed respectively inside and outside the base of said bowl, tightening means extended through both said plates and through the base of the bowl between them to clamp the said base between the said retaining plates and to integrate the said plates as an element of the bowl, and a tubular agitator-mounting post extended from said outer plate said inner plate and the base of the bowl between them upwardly into the interior of the bowl to introduce a motor shaft in leak-proof manner into the bowl.

12. In a mechanical mixing bowl assembly the combination of a flexible bowl, opposed reta;ning plates placed respectively inside and outside the base of said bowl, tightening screws extended through both said plates and through the base of the bowl between them to clamp the said base between the said retaining plates over the major proportion of the area of said base and to integrate the said plates as an element of the bowl, the shanks of the said screws being extended beyond the said outer plate to provide positioning pins for engaging the bowl to the casing of an electrical motor without obstructing removal of the bowl therefrom, and a tubular agitatormounting post extended from said outer plate said inner plate and the base of the bowl between them upwardly into the interior of the bowl to introduce a motor shaft in a leak-proof manner into the bowl, and a bladed agitator carried by means mounted on said post and having blades arranged to force material downwardly in the bowl.

RUSSELL E. IRISH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,141,358 Portmann June 1, 1915 1,839,082 Burgard Dec. 29, 1931 1,930,948 Brewer Oct. 17, 1933 2,226,372 Cravaritis Dec. 24, 1940 2,284,155 Landgraf May 26, 1942 2,304,476 Poplawski Dec.8, 1942