US2233727A - Apparatus for conditioning molding sand - Google Patents

Description

March '4, 1941. w. J. BELL 2,233,727

APPARATUS FOR CONDITIONING MOLDING SAND Filed Oct. 26, 1938 2 Sheets-Sheet 1 March 4, 1941. w J BELL 2,233,727

APPARATUS FOR CONDITIONING MOLDING SAND Filed oct. 26, 1938 2 Sheets-Sheet 2 6 6 mm 3 46 I- as a2 39 I 31 36 I U 5 l i 2* E 54% {E E .Eg. A-

\nvgfibw Patented Mar. 4,1941 g I 2 233 727 UNlTED STATES PATENT OFFICE Willard J. Bell, Newaygo, Mich, assignor oi' one- 6 Claims.

. vThis invention relates to a machine for rapidly and expeditiously breaking up and conditionin materials which may have lumps or small masses of material collected together adhesively more or- 5 less throughout the mass of material, it being'a primary object and purpose of the present invention to reduce the material mass to a finely divided or substantially granular state with a thorough aeration of the same and entrapment within the material after the process has been completed of a considerable supply of air. One place where the mechanism and the process which is followed is of particular utility is in the conditioning of molding sand, either fresh sand 15 or alter the sand has been used in molds and is returned for further use in other molds. Another place is in the breaking up and pulverizing of clay which is many times desired in road building. Lumpy salt which has become adherent pletely reconditioned and reduced to a desired uniform granular character with the machine and in accordance with the process of my invention. This invention provides a machine and a process which are most eiiectively used in the treatment of molding sand mixtures in foundries. Socalled molding sand is usually a mixture of sand and a bonding material and water. The sand when fresh usually contains considerable vegetable ilbrous materials such as small roots, etc.,

which are objectionable for molding purposes. The bonding material commonly used contains considerable silica and has considerable afiinity 35 for water and when mixed with the sand its tendency is to absorb water and form into lumps of various sizes. This invention provides a means for disintegrating the lumps of material and separating it into granular form, thoroughly homo- 40 genizing the bonding material with the sand particles, separating the fibrous material so that it can be screened out of the mass and introducing a considerable amount of air into the mixture leaving it in a light and relatively flufly 1;, condition. Such treatment of the molding sand may be initially with fresh molding sand materials which have never beforebeenjused in.

molding; or in connection with sandwhich has been used, has been shaken out of the flasks and 50 is to be reused, ,0! course with the addition of the necessary new materials which always have to be supplied to properly prepare and temper the sand for subsequent molding use.

An understanding of the invention may behad 55 from the iollowingdescription, taken in connection with the accompanying drawings, in which: Fig.1 is a vertical'section taken through the machine between the ends thereof.

Fig. '2 is an end elevation of a machine made so in accordance with my invention.

while standing in storage bins may also be com- Fig. 3 is a vertical section taken lengthwise of the machine.

Fig. 4 is a perspective view of one of the cutting and beating arm units, and

Figs. 5 and 6 are fragmentary details illus 5 trating the manner in which the wire brush elements of the machine are adjustably mounted therein.

Like reference characters refer to like parts in the different figures of the drawings.

In the construction shown, the machine comprises a housing into which the sand is delivered and wherein it is acted upon by the beating and disintegrating members, said housing having vertical sides I of sheet metal, a vertical back 2 and a top member 3 which partially covers the open upper side of the housing but leaves an opening between one edge thereof and the back 2 for sand entrance, said top member 3 being continued in a vertical member! in a downward direction for a distance and terminating in an inturned inclined lip 5 (Fig. l). The housing structure of the machine is strengthened and reinforced by frame members 6 of angle-bar form, as shown, and at the, bottom is surrounded by a frame of channel bars I.

The front of the machine opposite the vertical back 2 is open below the lip 5 and the framebar i at the same side of the housing, in which opening a sheet metal plate 8 of the form best shown in Fig. 1 is adjustably mounted. Adjacent its upper edge through suitable bosses 9 attached thereto, it is carried on a rod III which extends between the sides I of the housing, which rod at its ends passes through guide slots II made through the side plates I and disposed at an acute angle to the horizontal and vertical. The ends of the rod I are threaded to receive screwthreaded nuts IIia (Fig. '5), the tightening of.

which will hold the rod III in any position in the 40 length of the slots II to whichadjusted. Other slots I2 horizontally positioned are cut through the sides I at points considerably belowthe posi--' tion of the slots II, through which members having circular heads I3 and outwardly extended threaded shanks I! are passed, the heads I3 being at the inner side of the plate 8 as shown in Fig. 6. Over each threaded shank a collar I is passed which has a finger I6 at one side which extends through slot I2 and is located at the outer or opposite side of the plate 8. A threaded hand wheel nut Il screws onto the shank I4 and j a lock nut I8 against it, as shown in Fig. 6, for

the same extending radially inward. A Bolts 22 I I have heads against the 'innen-side of each 01.17128- bars 20 and'pass. therethrough. and. thacompanion;

bar I9, the threaded ends of thebolts receiving nuts at the outer side of the plate 8-. In: this manner the brushes .are securely held inzplace but may be readily removed should it become necessary for repair, cleaning or replacement.

A shaft 23 having an intermediate section 23a square in cross section, is mounted in and extends through bearings 24 supported by thechannels I. larged openings 25 in the sides I of the housing. In the operation of the machine, as hereinafter described, air is drawn inwardly through said openings 25. A plurality of beating and cutting members; are'mounted on and extend radially from the intermediate portion of the shaft. within the. housing. vYoke members 26 shaped at their inner sides to engage two sides of the square portion of the shaft are bolted togetherin pairs around the shaft, from each of which .a socket 21 extends outwardly, in which a cutting and beating member 28 is secured at one end.

Theend beater members indicated at 28a have outer sides parallel with the sides I of thehousing'and inner. sides in a plane located at an angle .to theouter-sldes. so that at one longitudinal side of each of the beater members28a there is a substantiallyHsharp'ened edge. The intermediate members 28. have both sides 29 converging toward-one edge, as shownin Fig. 4. Said cuttingand beating members 28 are secured in place by a securing block 30' and screws, as shown in Fig. .4.- .The beating. members 28 are located .alternatelyi-inrightangle relationship to each other along-izthe shaft section 23a and provide in ;.eflect1 aJrotating' cylinder somewhat similar tothe-cylindersmsed in threshing machines and filling .the -maior. portion, of the space between thezopposlte sides t -ofsthe housing of the machine. The shaft 23 and ..the radially extending beater'members N -mounted thereon are located downwardly oi and to one side.of the brushes 2| thelloutenendsmf" the members 28' coming very'closely adjacent to the innerends of the brushes 2!;jas best shownin Fig. laand of course S81'd:';b1'-l1heS.-'2| may beadjusted to desired posi-' tionstob-ring thejendsthereof as close as may be -required io the ends of the heaters 28. ,-;Bcarings 3i aresecured to plates 32, one at the 011tside of,-.each ofthe sides I of the housing, which-plates arm-guided" in spaced guides 33, securedtpjsaidsides I, the guides being located at an-(acute. angle .to the horizontal, as best shown in Fig.- 2.; An angle bracket 34 is secured to the outer side of each-side I, to the outwardly extending leg of which the adjacent bearing is adjustablysecured by meansof bolts 35 (Fig. 2). A rod 35- connected with each bearing, passes through the; outwardly extendlngleg of bracket 34, at=its outer. end being screw-threaded and having nuts. thereon between which and said bracket leg a coiled compression spring" 36a is positioned.

A shaitj'l extends through slots in the sides I, which slots are located at the same angle to the horizontal as the guides 33, and is mounted for v rotation in bearings 3|, the intermediate portion of said shaft within the housing of the machine being square in cross section. A plurality of arms 38 having a rectangular cross section, are each provided at its inner end with a rod 39 which passes through the intermediate portion 310. of the shaft and is equipped with a nut at its freeend to secure the arms 38 on the shaft.

The shaft 23 passes through en- 'tionsof the brushes.

Baldarms farezlocated in spaced apart relation and .aroundhthe shaft at the four sides thereof,

as bestindica'ted in Fig. 3. The shaft 31 is 10- cated-above the shaft 23' and also'above the brushes N (Fig. 1). I

The shaft 2-3 may be driven from any suitable source of power. It may be directly connected with an electric motor or it may be driven by bolts from any power line or prime mover, the belts passing around a drive pulley MI secured at one end of the shaft. (Fig. 3). At the opposite end of the shaft 23 a pulley I is-secured and at' the same end of the shaft 31 a pulley 42 of smaller diameter is secured thereto. On the adjacent side of the housing two idle pulleys 43 are mounted for rotation, as indicatedin Fig. 2. Endless belts 44 pass "around the pulleys ll, 42 and 43. A v

The opening between the upper edge of the back 2 of the housing and the adjacent edge 0! 20 the top member 3 is for the entrance of the materlal which is to be treated. A plate l5 located in the position shown in Fig. 1 will direct the material downwardly and inwardly while other plates 46, inwardly offset as shown-at. Fig.3, will direct the material inwardly at each end. The shafts 23 and 31 and the various arms 28 and 38 are mounted thereon, rotate at high speed in the directions indicatedby the arrows. Molding sand with the proper amount of moisture, 30 binder and other ingredients necessary and, as is usual, with portions thereof in small adherent masses or balls and sometimes intermixed with fibrous material, when fed into the machine is acted upon by the rapidly cutting and beating 36 arms 28 which in aconsiderable measure cutand shatter and otherwise disintegrate such balls or masses or adherent material. The direction of rotation of the arms 28, together with the centrifugal action'which results from the rotation, tend to throw the sand into the upper portion of the housing. This tendency is counteracted and completely overcome by the movement of the arms 38, against which the sand will strike and be, carried downwardly and inwardly toward the arms 38 and to the brushes. The material there uponis carried through the projecting end pore In practice the space between thefree end portions of the brushes and the plate 3, will be filled with the molding sand, leaving an-efiective projection of substantially one inch or. one and V one-half inches of the brush bristles through which't'he' sand is carried and vis finely divided homogenously dis'sem'inat ing the bond material throughout the sand and separating the fibers therefrom and at the same time introducing air into the mass.

With the .machine of the structure disclosed operating as described,'the various'molding sand ingredients entered into the machine in-a more or less unmixed or incompletely mixed condition are very thoroughly and'complet'elyand homo geneously intermixed, the bondmaterial is homogeneously disseminated throughout the sand mixture, lumps and 'balls adhering together are broken up and disintegrated and the sand as it leaves the machine at the bottom thereof is in a fiufl'y aerated condition. Air is .drawn through the openings at 25 and disseminated throughout the mass of sand and goes with it, whereby when the sand leaves the machine it is in a cool screenable condition. The sand is sufllciently cool that it will not stick to the pattern plates'and pattern as hot sand will do. The bonding material such as Bentonite or other bonding material used which is of a very sticky and adhesive character, is likewise very thoroughly and completely homo geneously disseminated throughout the sand and by such dissemination its adhesiveness is reduced 5 and overcome. The sand after it leaves the machine may be screened if necessary and is ready for use in molding. With sand in the finely divided and thoroughly mixed condition that this machine and the process which it carries out produces, casting losses in molding are very much reduced. The small masses of sand and other materials adhering together such as would make small balls in a mold and which are productive of blow-holes in a casting are eliminated by this machine.

While I have particularly described the intermixing of the several ingredients which enter into the production of molding sand, it is to be understood that other materials such as clay, salt, fertilizer and the like may be broken up insofar as any adhesive masses therein may be concerned and thoroughly reduced to small particles or granules, and whatever the material used, the resultant product when leaving the machine is of a homogeneous character throughout.

The invention is very practical and useful, has been commercialized and has been exceptionally satisfactory in use.

Having thus fully described my invention, what I desire to secure by Letters Patent is claimed in the appended claims and the invention is not to be limited in any respect other than is necessitated by the terms of said claims.

I claim:

a 1. In a machine of the character described, a housing enclosure open at its bottom, a rotatable shaft extending through the housing, a. plurality of radially extending arms mounted on the shaft in the length thereof and between the ends of the housing, said housing having an opening in its upper portion for entrance of material to be acted upon, means for directing material entered through said opening into the path of movement of said arms, disintegrating means having flexible elements projecting toward but slightly short of the ends of said arms, a second rotatable shaft extending through the housing parallel to the first shaft and above and between said shaft and said disintegrating elements and to which said arms impel the material to be acted upon, said second shaft being rotatable in a direction opposite to the first shaft, and arms on the second shaft radially extending therefrom to project the material between the first named arms and said flexible elements, said arms on the second shaft,

being spaced 9. distance from said material directing means.

2. The elements in combination defined in claim 2, said arms carried by the first shaft being triangular in a cross section on a plane normal to the radii and each having a sharpened edge which engages with the material delivered into said housing.

3. In a machine of the class described, a. housing open at its lower side and having an entrance for material at its upper side, a horizontal rotatable shaft extending through the housing, a pinrality of arms extending radially outward from the shaft andcarried thereby, a material directing means carried by the housing below said entrance opening for, directing material ahead of the movement of the arms, said shaft being rotatable in a direction whereby the arms engage and disintegrate said material, a member carried by 7 the housing having a plurality of wire brush ele- Y ments projecting therefrom toward said arms, the

ends of which come closely adjacent to the outer housing and mounted above and in a vertical 6 plane between the first shaft and said wire brush elements, and a plurality of arms having rectangular cross section in s plane parallel to the radii carried by and extending radially outward from the second shaft, said second shaft being 1c rotatable in a direction opposite to the rotation of the first shaft to receive material projected thereto from the first named arms and impel same to between said first named arms and said wire brush elements. 1 i5 4. In a machine of the character described, a rotatable element having disintegrating projections, a stationary element having disintegrating projections cooperating with and extending to-- ward those of the first mentioned, element, the 2G projections of one of said elements being rigid and those of the other being flexible, and a. second rotatable element having arms radially projecting therefrom located to one side of and between the disintegrating projections of the first two it mentioned elements and rotatable in a direction opposite to the direction of rotation of the first rotatable element, whereby material entering the machine will first reach said first rotatable element and be projected toward the second rotat- 3% able element, and thence between the first rotatable element and the projections on said stationary element.

5. In a machine of the character described, a housing having an open bottom and a material 35 entrance opening at its upper side, a horizontal shaft extending through the housing and mounted for rotation, the sides of the housing having openings larger than the shaft for air entrance, arms having narrowed or sharpened edges con- 40 nected to said shaft and movable therewith, said arms being spaced apart around the shaft and spaced lengthwise of the shaft, 2. plate mounted upon the housing and forming a closure at the rear side thereof, flexible disintegrating projec- 5 tions carried by said plate cooperating with andv extending toward said arms,materlal directing means for directing material entered into the housing at the upper side thereof into the path of movement of said arms wherebysaid material is 50 shattered and disintegrated and projected upwardly and to the rear, and movable means mounted in the path of movement of said projected material and moving in a direction opposite to the movement of said material to direct 55 the same between said arms and said flexible disintegrating projections.

6. A machine of the class described comprising, a horizontally rotatable element having radially projecting disintegrating arms, an element hav- 50 ing flexible disintegrating projectionscooperating with and extending toward said arms, and a second rotatable element mounted to turn about a horizontal axis located above and between said shaft and disintegrating projections having radially projecting arms, said second rotatable element being driven in a direction opposite to the direction of rotation of the first rotatable ele- 1 ment, whereby material to be disintegrated will 7 first reach said first named element and be proiected, thereby to said second rotatable element

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