US1185117A - Mechanism and process for mixing and transporting concrete and similar materials. - Google Patents

Description

MECHANISM AND PROCESS FOR I. H. MAcMICHAEL- MIXING AND TRANSPORTING CONCRETE AND SIMILAR MATERIALS.

APPLICATION FILED SEPT-6.1910.

Patented May 30, 1916.

2 SHEETSSHET I.

r ,J. H. MAcMICHAEL. MECHANISM'AND PROCESS FOR MIXING AND TRANSPORTING CONCRETE AND SIMILAR MATERIALS.

APPLICATION FILED SEPT-6.1910.

mm m MM m m M. n, 1 n M 8% J 09 0 fl 3 M Wm M W 9 Mn M W w m M 7 n I (0 Au 7 P WW g m QM w w .A Z 7 A 1. 1 v 5, e 8 .w/W 1 w m 1 w J U TED STATESATEN A JOHN H. MAOMICHAEL, OF TOIECBO,

OHIO, ASSIGrN'OlR. [DO-CONCRETE MIXING AND CONVEYING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

MECHANISM AND rnocnss ron MIXING AND TRANSPORTING CONCRETE AND SIMILAR- MATERIALS. 1

Specification of Letters Patent.

Application filed September 6, 1910. Serial No. 580,582.-

Concrete and Similar Materials, of which the ,following is a specification, reference being had therein to the accompanying drawing.

This invention relates to improvements in mechanisms for mixing the ingredient materials (rock, sand, cement and water) of concrete as used in making artificial stone be carried out.

and kindred bodies, and for, rapidly conveying them during the time of mixing, to distant points, the simultaneous mixing and conveying being effected pneumatically.-

It also relates to improvements in the methods or processes followed in handling such materials.

The objects of the invention are to produce a superior final product, to expedite the producing and delivering of the composite materials, and to economize in the manufacture.

Of the accompanying drawings: Figure 1 is a view partly in elevation, partly-in section, showing conventionally, and somewhat diagrammatically, an apparatus composed of parts by which the invention can Fig. 2 is an elevation also conventional and diagrammatic, illustratceptacle.

in initial holders, 2, 3, 4:.

ing more completely such an apparatus. Fig.- 3 is a fragmentary view similar to Fig. 1, but showing a modified form of re- Fig. 4 is a view, mainly in plan,

of the main receptacle and of the collector in Fig. 1. Fig. 5 ,is a partial cross section of the main plischa'rge pipe, the parts being shown on a" arge scale. F'g. 6 is a longitudinal section of part of the main discharge duct. Fig. 7 is a cross section of the same. I i

In the drawings, 1 represents a receptacle I into which are fed, the materials which are to form the composition. And for present purposes I will assume that the composite material is to concrete. 'To produce it, predetermined pro-. portioned quantities of cement, sandand broken rock are brought together in this receptacle. They are respectively contained Each of these has be of the nature of ordinary -The pipes or a tube or pipe connecting it with the main receptacle 1, these being shown at 5, 6 and :7. With the materials above specified, there is supplied also the proper quantity of water, this8 brought from a tank such as indicated at The main receptacle 1, communicates with and terminates at its end in adelivery conduit 9. This is extended to the point where a concrete material is to be finally placed, as will be more fully described below, and is made and arranged in either of several ways.

t ial wider vertical part and the bend, curve or elbow at the bottom, may be made in one piece, as shown in Fig. 1, or in two or more pieces, as shown in Fig. 3, where the curve I or elbow part is indicated as bolted to the vertical part.

The introduction of the initial materials, and the mixing of these and the water, as well as the propelling or transporting of the concrete mass, are caused by the following means: 10 indicates a receiver for compressed air. It is illustrated conventionally, as is also an air -compressing mechanism at 11. The air is drawn by suction through ducts or pipes 12, 12 the main receptacle 1. When the dampers or controlling devices at 13, 1 1, 15 inthe tubes or pipes, 5, 6, and 7 respectively are properly adjusted, the air which enters at the orifices 16 of the pipes 16, causes the passage of the respective materials through the pipes to the receptacle 1. dropped from the air current, the air escaping. from the receptacle through" the aforesaid pipe 12. To guard against any dust, or particles foreign to the air, being carried with it to the compressor or other parts, a collector is e ventionally illustrated at 20. The air from the receiver is taken through a pipe 21' to a main 21 from which it canbe carried by pipes to the places desired. One body of air is carried to the water tank 8, through a pipe 8", from which the water is forcibly ejected under pressure through pipe 8. ducts 5, 6, and.7- are so ar ranged as to deliver their materials at points where they can be impinged upon by the incoming stream of water. -As shown in the drawings, their delivery ends are in the arc of a circle and the water supply pipe is tan- This receptacle 1, including the inifrom the interior of They are.

mployed such as is ,con-

Patented May'30, 1916.

gential to the circle'so that the water causes a whirling or gyratory motion of the particles of the masses, not only insuring that they shall be moistened, but, to some extent, initially commingled.

That the action of an apparatus ofthis sort may be understood, and the method of manipulating the materials, I'will call attention towhat I understand to be the physical and chemical characteristics of the materials for the handling of which the mechanism was designed. Those bodies which are used as the principal ingredients of the composite masses for producing artificial stone or rock are found in one or another crystalline, or analogous form. They are held in such form while they include a quantum of water, to-wit the water of crystallization. In preparing-them-for use in producing the artificial bodies referred to, they are subjected to heat for the driving off or disassociating of one or another undesirable bodies, this heat resulting in breaking down the crystalline structure and driving off the water of crystallization. When, at a later time, they are to be used for forming artificial rock bodies, their tendency to again crystallize in the presence of water is availed of. To a given quantity of such material (either alone, or in mix ture with other bodies) a corresponding.

proportionate amount of water is added. Immediately upon the water coming incontact with the particles of material, its crystallizing action again commences, this resulting finally in its hardening or setting.

If the crystallizable material is physically mingled with others prior to this, they also are-bound together by the crystallizing, and, after the mass has hardened or set, constitute parts of the final hard or rocklike com posite. If after the particles of water commence their action upon the particles ,of crystallizable material the mass, as a whole, or any parts thereof, is agitated by shaking, stirring or the like, the total setting or hardening efficiency is reduced correspondingly, first from the fracture and breaking up of the smaller initial crystals and, second, byinterfering with the coheringof crystal with crystal throughout the mass. It will be seen, then, that there are two requisites for the production of artificial bodies of this class, ofa most superior character; first,v

that the water should be distributed through the mass in the shortest possible period of time, and, second, that this distribution of the water through the mass of crystalliZable material, when used alone, or through the composite mass of that material, and any others that may be added, shouldbe accomplished with the least agitation possible; or, that, where agitation is required it should be performed as near instantaneously as possible.

' Heretofore the mixing of mortar, concrete, cement, gypsum and the like bodies has been accomplished without bodily movement, by means of jets of fluid such as air or steam or by mechanical mixing devices of one sort or another, such asspiral mixing blades in troughs, or rotary. cylinders or drums, sometimes with and sometimes without mixing or beating arms, or structures similar in general character to these.

I have succeeded in mixing large masses of concrete and like materials in a few seconds, four or five, and also simultaneously delivering the finally mixed composite mass almost instantaneously to distant oints, one hundred feet or more in some instances, whereit can be immediately put in the position where it is expected to harden into rocklike form immediately after the water has been brought into contact with the crystallizable ingredients.

I do not limit myself to the details of structure which I have shown in the accompanying drawings, as I have carried out my process in mechanisms of various forms; those appearing in the drawings being selected as types and for the purpose of givlng a complete understanding of what is accomplished by such devices when operated in the described manner.

. Byassumption, the hoppers or bins at 2, 3, 4, respectively contain, cement, of any known constitution, sand, and reduced rock. By opening the valves or slide dampers at 13, 14, 15, these separate ingredients can be allowed to pass down to their several conduits 5, 6, 7, in any desired proportions. Each of these conduits, as aforesaid, has an air inlet at 16, so arranged and directed that the incoming jets of air will carry the streams of materials along the ducts and down into the main receptacle 1. Here the principal parts of the sol-id matter will settle, while the air body is drawn out and on through the outlet duct at 12 12 toward the air compressor 11. As the smaller dry, or dustier, particles of the cement, sand and rock "may be suspended in the air current and carried with itinto the outgoing duct,

'I prefer to insert into the air passage a Returning to the points Where thecement and other solid materials are initially introduced; I prefer to deliver the requisite water simultaneously as they enter. This may be done by delivering periodically separate amounts of water proportioned in numsure of air for injecting ceptacle 1.

' the water is her and quantity tov successive parts of the mixture of solid materials. But I prefer to deliver a continuous regulated and measured stream of waterv in such way that its mechanical action, when entering, can be utilized to effect at least an incipient mixing or mingling of the solid body. I employ a water tank 8, situated either ata relatively elevated position, where the head of the water can be used to drive it somewhat forcibly into the receptacle; or place it in a relatively low position and supply tothe upper part of the tank a part'of the body of compressed air. For example, from the receiver 10, or from the intermediate main 21*, an air pipe 8", can be employed which, under the control of suitable valves, will deliver the desired quantity and presthe water into re- In the mechanism shown in the drawings this water is taken in on tangential lines and on a horizontal plane near the top of receiver 1, and so directed that driven across the vertical lines, along which the cement and other bodies are dropping. This causes the incoming solid materials to become mingled, and also insures that the water shall, to some extent,

be quickly distributed through the general mass. But the principal agency in effecting the rapid mixing of crystallizable particles, and uniformly commingling all of the solid bodies, is a mass of compressed air, to forcibly and rapidly drive the solid masses out of receptacle 1, and along an elongated duct, which latter, as will be noticed below, is also used for tion forhardening or setting. To accomplish these results a body of compressed air is taken into the receptacle 1, and delivered at points above a part of, or the entire, mass. A mechanism like that in the drawing delivers'such a bgdy of air in the form of a powerful jet, which enters from the receiver'lO, or from an intermediate main 21, through the air duct 22, which is opened, closed, and controlled, by the valve at 23. As seen on examining Fig. 1, the air enters in a direction tangential to the lines of movement of the bottom'of the receiver 1,-and. drives it laterally out the lower end of the receiver, and through and along from then receiver 1, are successively expelled by the blast, the upper part of the mass rapidly settlesinto the pathway of the incoming air,-

the water with the .P

and, 1f this duct is ofa s1ze properly related 10o delivered in such way as supporting and guiding the material to the more or less'disto permit mass in the the trunk or duct at As the lower parts of the mass or body in bring, all

the air. I construct the receptacle 1, particularly the lower part of it, in such way that the vertical walls will not act to con fine the mass or cause choking thereof in its downward movement, this part of the apthe material downward to continuously feed so it into the path of the lower jet. In the present instance, this part of the mechanism 1 is so designed that the feed of the material will be readily caused by its gravity, and

the walls of the receptacle so shaped and re lated that they will not impede its downward movement. The wall 1*, is approximately vertical, though, by preference, it tends to curve outward or away from the vertical, so that the material can move easily a without obstruction.

The best results are attained by having the deliverypipe9 of a relatively large diameter so that there shall be freedom for these relative movements of the rock particles and of the submasses that are forcibly impelled ahead of the air jet. The delivery pipe itself becomes a mlxing chamber wherein neumatic mixing is effected or continued,

to the other parts, and to the sizes of theparticles of the materials, the latter can be rapidly impelled through it without danger of clogging or and mixing pipe 9 should be from six to ten inches, the latter generally preferable, this being in contrast with the relatively small delivery tubes frequently used in pneumatic apparatus, and not designed, as described, component particles as will insure perfect mixmg.

Considering the confined region extending from the'top plane of the material in the receptacle 1 down through that receptacle, and

then through and alongthe duct 9 to. its discharge exit as a path of movement for the material, it willbe seen that this path.

is, at one or more places, partiallyobstructed or. reduced. Thus, the escape orifice at the bottom of the receptacle 1, provided by converging the walls of the receptacle to the entrance orifice of the duct 9, can be regard: ed as a partial obstruction, which acts to the earlier 75 choking. The engineer, in .any lnstance, will readily understand what 1o5 such relative motions of large 115 he particles of the several masses in the receptacle 1 to a reduced passageway, and 'this assists in the mingling of the masses and also assists in delivering them properly to the air; jet at the end of the duct.. Again, the elb ovwor bend in the duct immediately below the receptacle is, to some extent, an obstruction in the path of the material, which assists in breaking up the masses as they impinge upon it, and enables the air blast to get an effective hold upon the particles, to insure their propulsion and further mingling.

I do not mean to exclude the use of a body of air delivered to the upper part of the receptacle 1, above the mass of contents for, if desired, such air can be introduced through a duct at 32 controlled by a valve 33. Indeed, under some circumstances, the body of air so delivered at 34 can be depended upon to accomplish the entire work of expelling the mass from the receptacle, and driving it along the delivering and mixing duct at 9. When air is delivered through both the ducts 22 and 32, the upper air body is distributed over a wide surface area and presses downward on the whole mass, While the air passing through the duct 22 is delivered as a reducted jet at a point where the resistance offered by the material is least and where this jet, because of its velocity, can effectively work against the small submasses of the material at the escape end of the receptacle. The upper air body, therefore, has the function of aiding the downward movement of the mass into the range of action of the lower jet and toward the outlet opening.

In the preceding paragraph I have referred to the upper air body as desirable in aiding the escape of material from the receptacle, but it is to be understood-that in some cases and for some classes of work this upper air body may be. omitted and the entire work of conveying and mixing effected by the single air the receptacle.

Turning now to the action of the air and I of the parts of the mechanismthat act on the material after it leaves the receptacle '1: The mechanical action of the air is such that as the particles of rock, and sand (when they are present) are rapidly whirled and agitated along the duct. And at the same time the cement and water being quickly brought into the contact necessary for crystallizing are coated upon these solid particles,;which, as is Well known to those practically acquainted with this work, is a necessity for perfect results. The reader has, doubtless, frequently observed, at places where concrete was being mixed, that large sub-masses of the rock, sand, etc., were, (even after the. various constituents of the general mass had been subjected to prolonged shoveling, agitating and rolling in mechanical mixers) jet near the bottom of still unafl'ected, that is were still with clean surfaces, frequently not even being moistened; and has further observed operatives with tools, brooms, or like implements, applying to such yet clean particles or masses,

a thin mass of waterand suspended cement,

the brooms being used to insure especial coating of these surfaces which have escaped from the desired action of the cement and water while going through the preceding treatment as parts of the general mass.

Materials passing through an apparatus such as herein shown and described and handled in the way set forth-is thoroughly coated, as to all of its particles, pieces of rock, etc., with the cement mass and the larger and the smaller particles are uniformly distributed throughout the delivered mass as an entirety. This results from the action of the air compelling such uniform distribution of the water that the thick moistened mass is carried through in uniformly constituted sub-masses. If three materials such as cement, sand and reduced rock were to be driven by an air-blast through a conduit while in a dry condition, the tendency would be for the light dry particles to be driven through first, and for those of the next grade in specific gravity, to be carried through as a second mass, such as the sand, separately from the cement, and for the rock pieces to be carried through as a still separated third mass. But inasmuch as the water and cement are introduced into the receptacle 1, they, by the time they leave that part of the apparatus, have commenced to adhere to the larger and heavier particle, and have commenced to form a general mortar-like mass, the consistency of which not only prevents the differences in specific gravity from separating one mass from the other while under the air blast, but on the contrary compels them to so intermingle that at the place of delivery it is found that a concrete body passing through this apparatus is thoroughly and completely mixed. Within a few seconds from the instantwhen the dry rock,

cement and sand are brought together in the receptacle 1, and after the instant when water is supplied, the thoroughly mixed concrete is at the place of deposit and ready for setting before the crystallizing action above referred to has commenced.

To assist in the mixing of the different masses among each other, as they are travelingthrough the duct, I prefer to provide the latter with devices such as spurs or sharp projections which, While offering no serious impediment to the rapidly advancing mass, break up any clots or large lumps to insure a more thorough mixing. Or, use can be made of a conduit such as I have shown in the drawings; this being a pipe or tube formed of sheet metal coiled the spirally extending edges of the sheet' provide what maybe termed a rifled path .for the material, so that as it advances under the action ofthe blast, it is compelled to whirl spirally insuring that the particles shall be rolled over and over and thoroughly coated with cement and intimately commingled. Metallic tubes or pipes for such purposes are susceptible of rapid cutting and wearing because of the abrasive action of the sand and rock. This I efiectually obviate by applying to the inner surfaces of the thin pipe metal a coating of non-abrasive material. By preference I use an ,asphaltum paint or coating. It can be applied by a brush or by immersion. I have succeeded in applying liquid bituminous substances by means of the air blast itself. A coating of this character protects the surface of the tube or pipe from the cutting action of the sand and rock even at those places, such as the bends where the impingement is the most violent for a long time.

It will be understood thatwhile a pipe such as I have shown having the inward ecting rivet heads and the inward exposed plate edges is for some reasons preferable, the invention is not so limited, and a pipe with a smooth interior surface can be used. i

The main pipe 9, may be connected in any suitable way with branch pipes such as at 30, and of the latter there may be any desired number, one extending in a horizontal of the building, and another extending to a higher floor. Between a series of branch pipes of such sort and the main duct, use may be made of a cutofi and deflecting valve device 29 of any suitable sort so that the stream of concrete or other material may be at one moment directed through one of the branch ducts, and at the next moment through another.

' In Fig. 2 I have shown how theprincipal parts of an apparatus such as above described, can be mounted upon av truck or vehicle frame so as to be ready for transportation from one place to another.

I do not herein claim any of the subjectsmatter covered by the claims in my copending application 642,400, filed August 4,1911,

. the claims in said other applicatlon relating to the process of mlxing and treating the in.- gredients of concrete and conducting them while being so mixed and treated.

The mechanism herein shown is characterized by having an immediatedelivery of the material from the initial receptacle to the mixing and conveying duct and having it immediately lmplnged upon by the air that initial ingredients,

' ured or regulated 1 direction, for example, as to the lower floor and intimately mixed, substantially as set 115 air directly in receive the ingredients of concrete,

with the upper part of .that it acts with the utmost efliciency.

What I claim is:

1. The herein described method of treating building material as concrete and the like, composed of two or more initial ingredients, which consists in conveying regulated quantities of the said ingredients to a receptacle by air currents, directly depositing the said ingredients in the receptacle, drawin the said air into a compressing mechanism and then delivering the air, under pressure, into contact with the materials in the said receptacle and pneumatically mixing and discharging the agglomerated mass therefrom, substantially as set forth.

2. The method of preparing concrete-like building material composed of two or more which consists in conveying to a receptacle regulated or measured quantities of said ingredients by currents of air, delivering to the said receptacle measquantities of water, with drawing the air of the said currents from the receptacle, subjecting it to the action of compressing mechanism, and delivering bodies of the said air after compression whereby there is efiected a discharge of the ingredients from the receptacle and an intimate mixing and intermingling of the ingredients along an extended path of movement.

3. In a concrete mixing and conveying device, the combination of a receptacle, a conduit leading therefrom,- the conduit being formed of spirally wound metal sheets having exposed inner edges, and means for rap= idly forcing material from the receptacle through the conduit whereby it is engaged the edges of the spirally wound sheets forth.

I. In a concrete mixing mechanism, the combination of the mixing and conveylng duct, the initial receiving chamber closely adjacent to the mixing duct and adapted to rock pieces, sand, cement and water in separate masses proportioned to constltute concrete, the short curved elbow-l ke duct connecting the receptacle immedlately to the mixing duct, the air pipe on the outside of the receptacle and of the elbow duct, the air orifice in the elbow duct arranged to deliver I the receiving end of the mixing duct, and the'air duct communicatlng the receptacle for desuch as 12 elbow duct to the initial end of the mixing duct, and the devices for delivering a body of air under pressure to the upper part of the initial receptacle.

In testimony whereof I aflix my signature, in presence of two witnesses.

, JOHN H. MAoMICHAEL.

Witnesses:

- M. B. CARNAHAN,

D. THoRP.

Images