US2627356A - Sand flow control mechanism - Google Patents

Description

Feb. 3, 1953 BELL 2,627,356

SAND FLOW CONTROL MECHANISM Filed March 14, 1951 I 2 SHEETSSHEET 1 IN V EN TOR.

M/'//ara J Be// Afforney Feb. 3, 1953 M. .J. BELL SAND FLOW CONTROL MECHANISM Filed March 14, 1951 2 SHEETS--SHEET 2 9 Afforn e)! Patented Feb. 3, 1953 UNITED STATES PATENT OFFICE N ewaygo Engineering Company, Newaygo,

Mich, a corporation of Michigan Application March 14, 1951, Serial No. 215,559

3 Claims.

This invention relates to an improvement in foundry sand hopper design and more particularly to a gate for regulating the flow of sand into one of two sand hoppers filled from a common source, whereby neither of the hoppers will be overloaded.

In the making of foundry molds, it is conventional practice to provide a sand hopper above each of the mold making stations, whereby the operator may easily and quickly drop the required quantity of sand directly from the hopper into the empty mold fiask. To conserve space and reduce the cost of equipment, it is conventional practice to provide a single sand elevator for filling a pair of hoppers, each of which hoppers serves one mold making station. When such a structure is used, it often happens that the molds are of appreciably different size. Therefore, unequal quantities of sand will be withdrawn from each of the hoppers, causing one hopper to become empty while the other one is substantially full. When this occurs, more sand is supplied to both the hoppers resulting in only partially filling one of the hoppers while the other hopper becomes overfull and spills.

The primary object of my invention is to provide a simple and dependable mechanism for regulating the flow of sand into each of the hoppers, whereby the required amount of sand may be supplied to each of the hoppers in accordance with the rate of use.

It is a further object of my invention to provide a means for automatically halting the flow of sand into a hopper when the hopper becomes full.

It is an additional object of my invention to provide means whereby sand may be supplied to an empty hopper while the other hopper is full.

These and other objects and purposes of my invention will be readily seen by those acquainted with the construction of foundry equipment upon reading the following specification and the accompanying drawings.

In the drawings:

Figure l is a front, elevation view of a foundry sand mechanism equipped with a pair of sand hoppers and a sand elevator for supplying both hoppers.

Figure 2 is an enlarged, sectional, elevation view taken along the plane II--II of Figure 1.

Figure 3 is a fragmentary, sectional, elevation view taken along the plane III-III of Figure 2.

Figure 4 is a fragmentary, sectional, elevational view taken along the same plane as Figure 3 but showing one of the hoppers filled with sand.

Figure 5 is a fragmentary wiring diagram of the electrical circuit employed for controlling the motor driving the sand elevator.

In executing the objects and purposes of my invention I have provided a pair of elevated sand hoppers having a common wall along one upper edge. A sand elevator centered about the common wall supplies sand to both of the hoppers. A gate is pivotally mounted at the top of the common wall whereby the sand from the elevator may be diverted into either of the hoppers as needed. Switches are provided for inactivating the sand elevator when the hopper being filled is loaded to capacity.

In the rollowing description the terms upwardly and "downwardly" are frequently used and are to be taken as meaning upwardly as the invention is normally used and as the invention appears in Figure l and downwardly away thereirom, The terms "inwardly and outwardly are also frequently used and are to be taken as meaning inwardly toward the geometric center or the invention and outwardly away thereirom.

Referring now to the drawings in detail, the numeral l indicates a vertical frame having legs 2 and a top structural hoop 3. Within the hoop 3 are mounted a pair of hoppers 4 and 5. The hoppers 4 and 5 are anchored to the hoop 3 by suitable means such as bolts, screws or rivets. Each of the hoppers 4 and 5 rorms a downwardly narrowing funnel closed at its lower end by a discharge gate 6. Each of the discharge gates B is made individually operable by means of a lever and pull chain combination 1. Downwardly, the hoppers l and 5 diverge whereby they discharge on opposite sides of the frame I.

The inward walls of the hoppers 4 and 5 converge upwardly and come to a ridge or apex 8 at the top of the hoppers. On one side of the hoppers 4 and 5 is a vertical, sand elevator 20 centered about the apex 8 whereby it will discharge equally into both of the hoppers. The sand elevator 23 is of conventional design consisting of a plurality of spaced buckets 2| mounted on an endless belt 22. The endless belt travels over a pair of rollers, one at the top of the elevator and one at the bottom. Only the top or driven roller 23 is shown. The entire sand elevator 28 is enclosed within a housing 24 having an external platform 25 for mounting the prime mover 26. The housing 24 is rigidly secured to both the hoop 3 and the hoppers 4 and 5 by means of suitable fasteners such as the rivets 27. The housing 24 has a canopy 28 extending inwardly over the hoppers 4 and 5 through which the sand is discharged into the hoppers from the buckets 2 I.

Rotatably mounted to the canopy 28, above the apex 8 and substantially below the driven roller 23, is a conditioning drum 30. A baflie 3| mounted within the canopy 28 directs the sand thrown from the buckets 2| onto the drum 30. The bafile 3| extends downwardly from the top 3 of the housing 24 where the housing 24 and canopy 28 join. The lower end of the baffle 3| is pivotally adjustable, about the bafiies upper end, toward and away from the roller 23. The position of the baflie 3| is controlled by means of the arm 32.

The drum 30 consists of a pair of circular end plates 33 mounted on a tubular core 34 (Figure 3). Four, equally spaced, radially extending fins 35, having scalloped outer edges, are mounted to the core 34 and extended between the end plates 33. The drum 30 is securely mounted to the shaft 36 for rotation therewith. The shaft 36 is driven by means of a belt 31 (Figure 2) passingover the pulley 38 secured to the shaft 39. The shaft 39 is-i-n turn rotated by means of the belt 46 driven by the prime mover 26.

Dependingfrom the lower edge ofeach of the sides ofthe canopy 26 is a flap. The flap 50 hangs into the hopper 4 and the flap hangs into-thehopper 5. Thelower end-ofeach of the flaps is substantially below the apex 8 and the hoop 3; The purpose of this will be explained under-Operation. Eachof the flaps 56 and 5|- is free to swing inwardly and outwardly about its-mounting hinges-58- (Figures 2, 3 and 4). Cooperating with each of the flaps 50 and 5| is an arm 52 and 53 respectively, mounting the electrical switches 54- and 55. Each of the switches 54' and 55 is provided with a central pin resiliently urged inwardly or toward the flaps50-and 5| tonormally close an electrical circuit. Theswitches 54 and 55 are so mounted on the arms that-they may beoperated by'the flaps 50'and 5| respectively.

Immediately above and extending parallel to the EIJBXB, a rod- BO-is-rotatably mounted in the hoop- 3'. Rigidly secured to the rod 60 is the panel or diverter'gate 6|. The diverter gate 6| extends substantiallythe entire length of the ridge 8 and hascutouts toprovide clearance for the canopy 28 and the drum 30;

A tube 62 is mounted through the diverter gate 6| beneath the Canopy 28 and substantially above the'rod 60. The tube 62 is rigidly secured-to the diverter gate 6| and is internally threaded on each endto receive thebolts'63. The bolts 63 are made adjustable so that they may properly actuate the- flaps 50 and 5|. At the end of the rod 6|],remote from the sand elevator 20; a cross bar 64 is securedto the rod 60 and mounts apull chain- 65' on each end;

Operation The sand is supplied to the lower end of the sand elevator 20 from which it is removed by the buckets 2|. As the buckets 2| pass over the driven roller 23; the sand is thrown toward the hoppers 4 and 5. The baffle3| directs the sand onto the rotating drum 30. The drum 36 is rotated rapidly to throw the sand into the hoppers 4and 5. In so doing, the drum 30'serves the dual purpose of'widely distributing the sand in the hoppers 4and 5 and of conditioning it by aeration as the sand is distributed. Sincetheapex 8 of the hoppers 4 and 5' is located midway between the ends of the drum 30, the drum normally throws sand simultaneously into both hop: pers in substantially equal quantities. This is the case whenthe diverter gate6| is in its vertical position (Figure 1'). Thisisa satisfactory arrangement whensand is withdrawn at anequal rate from both ofthehoppers lland 5. When,

however. as, frequently occurs, one hopper re-- 4 quires a much greater quantity of sand than the other, one hopper will become filled and spill sand over the side before the other hopper receives sufiicient sand.

To avoid this, the operator pulls downwardly on one of the chains 65 to pivot the diverter gate 6| toward the full hopper. The diverter gate 6| pivots until its upper end rests against one side of the canopy 28. All of the sand being delivered from the sand elevator 26 is diverted into the empty hopper. When this hopper becomes full, the, diverter gate 6| may be pivoted until it rests against the other side of the canopy 28. All of the sand will then be diverted away from the full hopper into the empty hopper.

When the diverter gate 6| is pivoted into an inclined position one of the bolts 63. will contact one of the fiaps 59 or 5| forcing it outwardly (Figure 3). The flap in turn. will depress the plunger ofthe adjacent switch causing it toopen the circuit. Since the switches 54 and 55 are arranged in parallel, the opening of the circuitby one of th switches will not inactivate the prime mover 26. The plungers of both switches 54 and 55 must be depressed before the prime mover 26 will be stopped. As the hopper into which the sand is being directed fills, the sand will pile up against the flap depending into this hopper. The weight of the sand will force this fiapoutwardly (Figure 4) to cause the switch adjacent this flapto interrupt the circuit. Since both of the switches 54 and 55 arenow open, theprime mover 26 will be stopped. The stopping of the prime mover 26 stops thedischarge of sand into the hoppers because the sand elevator 26 is halted.

As soon as enough sand has been withdrawn from the full hopper torelease the flap, the sandnism for regulating the flow of sand into a pair of sand hoppers, which mechanism is not only capableof. directing the flow of sand but also-of preventing overloading of either of thehoppers.

Numerous modifications of my invention maybe made, each without departing from the principleof-myinvention. Each of these modifica tions is tobe-considered as included in the hereinafter appended claims unless these claims by their language expressly state otherwise.

I claim:

l. In a foundry sand dispenser, a frame and a pair of hoppers mounted thereon, said hoppers arranged in side by side relationship and having at their upper end a common wall, a housing, conveyor means. within said housing centered about saidcommon wall for discharging sand into both of said hopperssimultaneously in substantially equal quantities, a prime mover for drivingsaid conveyor means, theimp-rovement insaid sand dispenser comprising: anupwardly projectmg panel pivotally mounted at its lower-end to saidframe parallel to andclcsely adjacent said common wall of said hoppers; a depending flap projecting into each ofsaid hoppers; means for pivotally mounting the upper end of each of said flaps to said housing; an arm extending outward- 1y from each side of said panel; means for mounting an electrical switch adjacent eachof said flaps on the side thereof remotefrom said common wall, each of said switches normally closing an electrical circuit; means for alternately pivoting said panel toward each of said flaps and urging one of said flaps against the adjacent of said switches for opening the electrical circuit; the other of said flaps adapted to being urged against the other of said switches when the hopper into which said other flap depends is full; said switches arranged in parallel in the circuit for said prime mover whereby said prime mover will be stopped when both of said switches are open.

2. In a foundry sand dispenser, a frame and a pair of hoppers mounted thereon, said hoppers arranged in side by side relationship and having at their upper end a common wall, a housing, conveyor means within said housing centered about said common wall for discharging sand into both of said hoppers simultaneously in substantially equal quantities, a canopy on said housing surrounding the discharge end of said conveyor means, a portion of said canopy projecting over each of said hoppers, a prime mover for driving said conveyor means, the improvement in said sand dispenser comprising: an upwardly projecting panel pivotally mounted at its lower end to said frame parallel and closely adjacent said common wall of said hoppers, a portion of said panel projecting into said canopy; a depending flap projecting into each of said hoppers; means for pivotally mounting the upper end of each of said flaps to said canopy; an arm extending outwardly from each side of said panel; an electrical circuit operatively connected to said prime mover; means for mounting an electrical switch adjacent each of said flaps on the side thereof remote from said common wall, each of said switches normally. closing said electrical circuit; manual means for alternately pivoting said panel toward each of said flaps and urging one of said flaps against the adjacent of said switches for opening said electrical circuit; the other of said flaps adapted to being urged by said material against the other of said switches when the hopper into which said other flap depends is full; said switches arranged in 4 parallel in said electrical circuit whereby said prime mover will be stopped when both of said switches are open.

3. In dispensing means for a finely divided solid material having a frame and a pair of hoppers mounted thereon, said hoppers having a common wall on the upper end and a conveyor means for supplying said material to both of said hoppers simultaneously, the discharge end of said conveyor means being centered about said common wall and being adapted to discharge said material in substantially equal quantities into both of said hoppers simultaneously, a prime mover for driving said conveyor means, the improvement in said dispensing means comprising: a shaft rotatably mounted to said frame parallel to and immediate- 1y above said common wall; an upwardly extending panel mounted to said shaft for rotation therewith; means on said shaft for alternately pivoting said panel towards each of said hoppers for directing the sand flowing toward one of said hoppers into the other of said hoppers; a pair of electrical switches mounted to said frame, one on each side of said panel; means on said panel for opening one of said switches when said panel is rotated in one direction and for opening the other of said switches when said panel is rotated in the other direction; said switches being arranged in parallel in the electrical circuit for said prime mover whereby said prime mover will be stopped when both of said switches are opened; swinging elements associated with each of said switches for individually opening each of said switches when the hopper adjacent each said switch is filled with said material.

MILLARD J. BELL.

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

UNITED STATES PATENTS Number Name Date 326,964 Fisk Sept. 29, 1885 419,401 Baldry Jan. 14, 1890 925,817 Lorch June 22, 1909 1,325,602 Albright Dec. 23, 1919 2,376,304 Anderson May 15, 1945

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