US2488381A - Apparatus for treating molder's sand - Google Patents

Description

3 Sheets Sheet 1 Filed Feb. 4, 1946 1949 s. B. DAVIES APPARATUS FOR TREATING MOLDER'S SAND I 3 Sheets-Sheet 2 Filed Feb. 4, 1946 View l'aldqy B Pa Nov. 15, 1949 s. B. DAVIES APPARATUS FOR TREATING MOLDERS SAND 3 Sheets-Sheet 3 Filed Feb. 4, 1946 vucw'ro'z 5212212951 3. 12511 195 R mm Patented Nov. 15, 1949 APPARATUS FORSTR EATING MOLDERS AND Stanley 3., Davies, Kingston, Pa., assignor to Boyer Foundry & Machine Company, Kingston, Pa., a corporation of Pennsylvania,

Application February 4, 1946, Serial No. 645,453

2 Claims. 1

The present invention relates toapparatus and methods for processing molders sandand particularly for recovering I sand which has i once been used, mixing it with an appropriate amount of new sand and eliminating foreign matter therefrom,- wetting down the sand to properly temper it,- and then blending and discharging the sand in fine particles into piles along the foundry floor preparatory-toreuse in forming molds.

r A'principal object of the invention is to provide apparatus :whichwill eliminate the collectingof sand by aseparate shift or group of workers after the mold flasks have been broken down to remove the castings therefrom. A I v It is also an object of the invention-to provide for automatically granulating, conveying and elevating the sand taken from the old moldsto a point where it may be discharged into a sand separator and blender orother device, and during the preceding-operations, to supply new sand to the mass to revivifyit and to then supply a regulated amount of water to the sand in accordance with the volume. of sand being processedor conveyed, in order that the mass of sand will be inthe best possible condition to be finally treated by the separator and'blender or other device, or collected for reuse Another object of the inventionis to provide a novel means for controlling the application of water to the sand in a uniform and automatic manner. Various other objects and advantages of the invention will becomeapparent as the description progresses.

In the drawings, which are illustrative of one form and arrangement which the invention may take, .and whichare not intended to.retrict the invention defined inthe claims:

Figure 1 is a top plan view of the shake-out, conveyor and combined separator and blender.

Figure 2 is a side elevational view partly in sectionof the abov assembly, taken along the line .-22, of Figure 1.--

Figure 3- is a side elevational view of the end portion of the conveyor and the separator, showingthe opposite side thereof from that illustrated inFigure 2. I l Figure 4is a transverse .vertical sectional view of the, shake-out taken along the line 4-4 of Figurel. q Figure 5 is an enlarged partial top plan view of theterminal'end of..the conveyorshowing the mechanism. for. applying water -to temper the sand as it drops into the separator. 1

Figure. 6 is a side elevational view of peringmechanismofliigure 5.

the tem- Figure 7 is an end view of the conveyor looking inwardly from a position indicated by the lines 'l---! of Figure 3. I

The invention is particularly useful in foundries where stationary-molding machines are used. In such foundries, processed sand is piled along the length-of the'foundry, usually against the Wall between adjacent molding machines; there usually being a row'of such machines along the wall with apile of sand between adjacent machines. When the molds have been made they are set on-the floor adjacent the machines and one shift of workers pours the metal into the molds.- When the metal has solidified, a second shift will break the molds and remove the castings therefrom, leaving the used mold sand togather with a considerable amount of. foreign matter in a confused condition on the fundry floor This-material is initially hot and somewhat burned from the heat of the metal, and to prepare it for further use, it is customary to add some new sand and then to moisten the mixture with waterin order totemper it. In order to provide a proper mixture for further use, and depending on the composition of the sand, it is desirable that the quantity of water added should be carefully and evenly controlled. The sand thus mixed and tempered is then shoveled into a sand separator or blender of well known type, such as is generally disclosed in Patent No. 1,559,915, to G. F. Royer, November 3, 1925, and in machines which constitute an improvement over that disclosed in said patent.

It will be obvious from the above that several shifts of workers are required to perform the above operations, including one shift to shake out the molds and remove the castings, and another. shift. usually working at night, to condition the sand and shovel it into the sand separator and blender so that it may be blended and properly disposed in piles ready for use in the molding machines beginning with the next days work shift. A A A In the present invention, a combination of equipment is provided to automatically carryout the above operations, includinga shake-out to break down the mold flasks and remove the scrapwhile processing the used sand into more or lessgranular form, a conveyor to receive this sand and carry it-to the separator and blender while providing for the addition of aregulated amount of water, and the separating and blend-- ing machine itself, which blends and discharges thesand by centrifugal force into piles-while simultaneously releasingthe confined gases from prises generally the conventional shake-out S on which the mold flasks are placed to be agitated" and broken down, the conveyonLC'whichicarries' the resulting sand from beneath the shake-out}v and the separator R which finally receives the the transverse shafts are oppositely pitched, so that when one strap is in its upper position, the adjacent strap is in its lower positions. As described in the Royer Patent 2,020,800, the units of the screening body are given movements by the cams so that one set is always moving in a direction opposite to that of the other, yet the rotational or translational movement of the two units with respect to the axis of a common orbit is always in the same direction, and the upper edges of the bargzZB and the fingers I8 exert a combined action on a mass of material disposed sand with water added thereto; and blends and distributes it with considerable velocity in rows or" piles onto the foundry floor in preparation for the subsequent molding operationsi understood that under certain conditions the separator may not be used. at the discharge end of the conveyor, or some other processing machine maybe" there interposed" toperform additional or different treatment.- However, an important feature of the invention is the controlled tempering ofthe mii'rture'of old and newsa'nd'for immediate-blending by the separator.

The shake-out maybe constructed in any appropriate well kno'wn manner; generally following the construction as disclosed in the Boyer Patent No. 2 ,020 j800 issuedNovember 12, 1935.

Asde'scrib'ed said patent, the 's'hake out com. prises aframe member f properly spaced from the floor on legs t2, the shake-out having a top surface or grid [4" (Figure 1) consisting of two units" or sets ofscreening elements; One is made upof aplurality of'vertic'ally and' longitudinally disposed parallel plates or bars it (Figure 4), each" of which is provided with transversely disosed parallel fi'n's or fingers I8; as described in s'aidpatent. 'I'h'e-individual' elements N; are rigidly secured together inpredetermined relation 1;

by meansof transversebolts having suitable spacer collars-along the l'engththereof. The bolts 211' are suitably supported in si'deframe members which are in turn mounted on lower frame members 21;

The other units orgr'ids of the-screening'body comprise a plurality" of parallel" longitudinally disposed screening plates or bars 26 (Figure 4) secured in predetermined relationto each other and between the bars I-"fi by'corresponding transversel'y' extendingbol'ts and spacer collars; The bars on which the elements 26 are carried are suitably connected with longitudinallydisposed substantially parall el angle iron supporting frame members- 2'8 as described in said patent.

Secured in' suitable journals mounted upon the main frame of the apparatus are apair of rotatableshaft's' 40' (Figure 2d. These shafts-arecon.- n'ec'ted to be rotated i'n unison by a counter shaft H; and bybevel gears as shown in Figure 1 and described in said patent. Driving movement is imparted to one of the shafts 40" by any suitable prime mover such as an electric motor 42, through any appropriate driving conection such as a' belt 43 inclo'sedwithin the housing 4'41 Upon each of the transverse shafts 40, there are mounted two pairs of eccentrics 4'6 and 48, these eccentrics being surrounded by suitable straps asfl described insaid patent.- The inner strapsare operatively connected to the supporting frame members 22 for the screening elements 1 6-, while the outer straps are operatively connected to the frame members 28 of th'erectangulei-supporting frame for the other set of screening elements 262 The" adjacent cams on each of It; will be on the grid,.separating relatively small granules from the mass of material and allowing same to fall through the spaces defined by the members [6 and 2B. The movements described impart a lbn'g'itiidinal'movement to any article or material which is not passed through the screen, and this movement is toward the left as the assembly is viewed in Figures 1 and 2, the left-hand end being; the discharge end of the shake-out, and being slightly elevated above the opposite end. It will be understood that the metal castings be:- ingbrok'en from the mold flasks; as well as'foreign objects such as wires andthe like; will b'edis} charged off of the left-hand end of the grid [4 as viewed in-Figure 2; while granulated sa-nd will fall through the openings of the grid.

If necessary, appropriate walls may-beprovi ded along and above the side edges of the gridin order to retain the flasks against displacement over the inlet and side edges of" the shake-out, but for purposes of simplicity, these have been omitted in the drawings.

When the mold flasks have been agitated and operated on by, the grid in a manner which will beunderstood from the disclosure of the Royer Patent 2,020,800 and my Patent 2206164, dated July 2', 1940; the sand thus shaken out will'drop through the grids into a hopper which dcpends from the'shake-out as shown in Figures 2 and 4; It will be understood tha'trthis hopper hassuitable front, rear and'side walls, thus completely enclosing and confining the falling mate.- rial, so that it is guided ontothe-horizontalflight of the conveyor C.

As best shown in Figure 2, theinlet end ofthe conveyor comprises-a box-like enclosure 5B'which rests on the floor or'is'supported' in any suitable manner, this structure gradually slanting upwardly and being supported intermediate the length of' the conveyor by leg members 58. Extending laterally betweenthe side walls of the supporting structure ofthe' conveyor are rollers 60" and 62", which are mounted for free rotation across the frame of the conveyor, and a belt 64 passes beneatl'r theroller 62' and around the roller 60. As shown in Figure 2; this conveyor belt" extends beneath the hopper 50 of the shakeout and is moved in the directionof the arrows to convey the material from the shake-out tothe separator or other device, or simply to a point ofdischarge; in the manner'hereinaft'er described, there being upwardly extending side walls 65 on each side of the conveyor belt to' retain thematerial thereon.

Beyond the inner end of the shake-out, the frame of the conveyor is inclined upwardly as shown in Figure 2, and there is a, conveyor roller 66 mounted for rotation across the frameat the terminal or upper end thereof. Referring to Figure 3', the roller 66 of the conveyor is shown as the driving element therefor; and' it is driven by a motor 10' mounted'on' one" side of the upwardly extending wall of the-conveyor. The motor'lfl has a driving connection with the roller '66- through belts or chains, there being an intermediate driven pulley or wheel 12 mounted for rotation on the frame adjacent the lower end of the inclined portion of the conveyor, this wheel being connected with the motor by a belt or chain 75, and with the drive roller 66 for the conveyor by a belt or chain 16 (Figure 3). The belts l5 and 16 may be suitably protected by housings l4 and 1! respectively. The belt 64 is normally driven by the motor continuously and at uniform speed. I

From the above, it will be apparent that the conveyor belt 64 when driven in the direction indicated in Figure 2, will carry granulated material received from the hopper 50 of the shake-out in an upwardly inclined direction and will discharge the material over the portion of the conveyor which passes around the roller 66 and into the inlet compartment of the separator R. The conveyor belt thus has a substantially horizontal flight extending beneath the shake-out and an upwardly inclined flight beyond the shake-out which elevates the material so that it may be discharged while being tempered into the inlet hopper of the separator.

At any appropriate position on the frame of the assembly, controls may be provided to selectively operate the shake-out, conveyor and separator motors. In Figure 1, such controls are shown as at 89, whereas in Figure 3 a separate control for the separator is shown at B2. Preferably, the electric control mechanism will all be positioned at one point such as at 89 in Figure 1, so that one man may control the operation of the assembly, there being necessary electrical leads, not shown, to accomplish these purposes. However, if convenient, independent electrical controls may be provided adjacent each of the agencies involved.

In order to temper the sand being delivered by the conveyor to the separator, a water pipe 85 is positioned transversely across the assembly just above the point where the conveyor delivers to the separator, said pipe being supported by mem bers 85 rigid with the side walls of the conveyor. As previously discussed, it is highly desirable to temper the sand with regulated quantities of water in accordance with the exact volume of sand which is being delivered to the separator. Proper regulation of moisture content of the sand greatly improves the operation of the separator.

The water pipe 84 may be provided with one or more downwardly directed outlet nozzles 86, and on the inlet side of the pipe 84 there is a control valve 88 whose degree of opening is governed by the volume of material being carried by the conveyor or delivered to the separator, to control the amount of tempering water being applied thereto. The nozzle 86 may have adjustable sections to basically regulate the amount of liquid to be delivered therefrom, in accordance with the composition of the sand being used, and after this adjustment has been made, the delivery of tempering water is under the control of the volume of material being delivered, as now described. The nozzle 86 may also be capable of regulation to cause the manner of discharge of Water therefrom to vary as adjusted between a simple stream to a wide spray, and the nozzle is also swiveled to control the direction of discharge of the water into the sand as it leaves the conveyor.

As shown in Figures 5 and 6, there is a relatively heavy material responsive metal plate 90 which extends entirely across the top surface of the 6. conveyor having movements controlled by the mean amount of sand conveyed. The plate is rigidly secured to opposite stub shafts 92 which are carried in bearings 94 integral with the side walls 65 of the conveyor, and on one side in bearings 95 on housing 11. The outer end of one of the shafts 92 rigidly carries a rocking lever 96, which is pivoted in adjusted positions to the end of a connecting rod 98. The opposite'end of the rod 98 is pivoted to an operating handle link I09, whose positions determines the degree of opening of the valve 88. When a relatively great quantity of sand is present on the conveyor belt, the plate 99, whose free end is presented in the direction of movement of the conveyor, is lifted upwardly as indicated in Figure 6, and this movement turns its stub shaft 92 in the bearings 94 and 95 and rocks the arm 96. The arm 93 in turn moves the connecting rod 98, and through the link [00, the valve 88 is opened to a controlled degree to permit passage of a greater amount of water to the nozzle 86. Conversely, when a lesser amount of sand is moving on the conveyor belt beneath the plate 90, the latter will drop and operate the valve to reduce the volume of water being supplied. Proper adjustment of the operation of the valve may be effected by selectively pivoting the end of the rod 98 at any one of a number of holes I02 in the arm 96, and when no sand is passing along the conveyor, the arrangement is such that the valve 88 will close.

The plate 99 is of sufficient weight to constantly bear down on the material on the conveyor, and it therefore smoothes out furrows and uneven masses of sand, making the distribution of sand uniform throughout the width of the conveyor. As is clear from Figure 1, the plate 98 is substantially rectangular in form and it is of width substantially equal to that of the conveyor, so that the plate is responsive to the total amount of sand passing its trailing edge at a given time, and it' distributes the sand so as to be responsive to a true measure of its volume. The weight of the plate is not, however, great enough to cause the sand to build up behind the plate. By reason of the even continuous movement of the conveyor belt, the movements of the plate are likewise even and continuous, and not erratic, so that the flow of water is evenly increased and decreased rather than being turned on and off. Hence, all of the sand discharged from the conveyor is supplied with a proper degree of moisture, as distinguished from having successive quantities which are either dry or saturated.

It will be understood that the uniform controlled water tempering is applied to said previously processed sand which has had new sand added to the old. The new sand may be distributed onto the mass of old sand at the lower end of the inclined portion of the conveyor, but I find that best results are achieved if it is thrown on to the grid of the shake-out, where it is mixed with the old sand by the oscillating grids and in the hopper 50, prior to reaching the conveyor belt. The proportion of new sand needed for best results will be known, and predetermined quantities may be thrown on the grid in accordance with the number of mold flasks being broken down per unit of time.

It will be evident that the plate 90 may be adjusted with respect to the valve so that the quantity of tempernig water is regulated in accordance with the particular work being performed in the foundry, and furthermore, the

amount new sand; addedmaybe similarly regulated.

Referring to' Figures 1 and 7, it will be; noted;- that opposite baffles I08 having vertically disposed inwardly converging walls H are pro-- vided at the terminal end of the conveyor on the side walls 65 thereof, The vertical walls H 0- terminate at 2 beyond-the conveyor roller 66';

These-bafiles or wings of the: sidewallscenter the sand for discharge" into the separator R, and prevent the sandfromspilling over the sides of: the conveyor belt and into the adjacent moving, parts'of the roller 66;

It will be obvious thatevarious changes may be made in the apparatus, as well as variations in the methods disclosed herein, without depart, ing from the invention as defined inthe appended claims. I

I claim:

1. In apparatus of the character described; a shake-out comprising a: grid spaced from the foundry floor to breakdown moldflasks andpermit the sand to sift therethrough whilepreventing passage of the castings and foreign matter, a conveyor having a section beneath said grid and a delivery section extending. beyond the same, said latter section being upwardly inclined to elevate the sand a substantial distance. above the foundry floor, said conveyor comprising a belt and means to'drive said belt continuously at uniform speed, a sand separator and. blender positioned directly beneath the upper terminal end of said conveyor toreceive the sand therefrom and to blend and; discharge it, in fine. particles for further molding operations, a movablemember pivotally mounted over the delivery section of said conveyor belt and having a substantially straight, free edge directed toward and positioned adjacentto the upper terminalend of said conveyor belt and extending entirely across the same, said member being continuously re-v sponsive in its movements to the mean quantity of sand passing upwardly along the delivery section of said conveyor at any given time, a pipe for supplying tempering water having a nozzle positioned to direct the tempering water into the sand beyond the terminal end of said conveyor as it drops'into said separator and a control valve for said nozzle, and means operatively connecting said'valve with said member to continuously govern the degree of opening of said valve in order to continuously regulate themoisture content of the delivered sand in accordancewith the volume of sand being delivered.-.

2. Inapparatus,- of the character described, a; sand separator and blender havingv a feed inlet and means tosupport same on the foundry floor, a shake-out comprising a grid spaced from the foundry floor to break downmold flasks andpermit the sand to sift 'therethrough, a conveyor having a. section beneath said grid and an upward'ly inclined delivery section arranged with itsdischarge. end positioned abovesaid separator to deliver sand directly into said inlet, said conveyor comprising a belt and means to drive said belt continuously upwardly at uniform speed, a relatively heavy plate pivoted over saidbelt and having a substantially straight, free, movable edge extending entirely across said belt and prersented toward the upward direction of travel of said belt, said edge of said plate being locatedimmedixately adjacent to the upper terminal end of said conveyor, said plate serving to retard the upward movement of the sand onsaid belt and to evenly and continuously distribute the sand over said belt whereby even regulatedquantities of sand are delivered-from said shakeout to said separator by saidconveyor, said con-- veyor having side bafiies at its discharge end to direct the sand inwardly toward the center of said belt for proper delivery to the inlet of said separator, a pipe having a nozzle positioned to direct tempering Water into the sand beyond the terminal delivery endof. said conveyor as-it-drops into said separator, said pipe having a control valve therein, and connecting means between said plate and said valve to continuously govern the degree of opening of said valve inresponse to the movements of said plate.

STANLEY B. DAVIES.

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

UNITED STATES PATENTS Number Name Date 762,596 Packer June 14, 1904 1,587,621 Walther June 8, 1926 2,206,164 Davies July 2,1940 2,273,126 McGillin Feb. 17 1942 2,331,102 Bird Oct. 5, 1943' 2,347,226 Whittaker Apr. 25, 1944 2,367,278 Hewlett Jan. 16, 1-945

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