US3081505A - Foundry aerating flask-filler - Google Patents

Description

March 19, 1963 G. M. BUTZOW FOUNDRY AERATING FLASK-FILLER 5 Sheets-Sheet 1 Filed July 3, 1959 INVENTOR. GEORGE M. BUTZOW BY 1M I M ATTORNEYS March 19, 1963 G- M. BUTZQW 3,081,505

FOUNDRY AERATING FLASK-FILLER Filed July 3, 1959 s Sheets-Sheet 2' 1N VEN TOR. GEORGE M. BUTZOW ATTORNEYS March 19, 1963 G. M. BUTZOW 3,081,505

FOUNDRY AERATING FLASK-FILLER Filed July 5, 1959 3 Sheets-Sheet 3 INVENTOR. GEORGE M. BUTZOW ATTORNEYS United States Patent Ofiice 3,0815%. Patented Mar. 19, 1963 3,081,505 FOUNDRY AERATING FLASK-FILLER George M. Butzow, 4821 S. Wayne Ave., Fort Wayne, Ind. Filed July 3, 1959, Ser. No. 824,856 3 Claims. (Cl. 22-35) The present invention relates to a foundry aerating flask-filler, and more particularly to a machine adapted to treat foundry molding green sand as it is being introduced into the flask, said treatment imparting to the sand a quality that enables it to form a superior mold as it is compressed against the pattern.

In the proper formation of a sand mold, it is necessary that the sand be treated properly and thereafter introduced into the mold box or flask during the moldforming operation. As a part of this treatment, it is desirable that the sand be fluifed or aerated to render it substantially fluid and flowable and further to break up and eliminate all lumps or clods of compacted sand which may form. After the sand is properly treated and it is desired to form a mold, the sand is sometimes sifted into the mold box or flask containing the pattern. After the sifting operation is completed and the flask is fllled to the proper level with sand, the sand is compacted to form the mold and the pattern is removed, leaving a mold cavity.

It is an object of this invention to provide a unique flask-filling device for use in foundries, which is substantially automatic in operation,is efficient in use, and is quite simple in construction.

It is still another object of this invention to provide a riddle machine for use in foundries which is operable substantially automatically to first aerate the sand and then immediately after to sift or riddle the sand into a mold box for the forming of a mold.

Other objects will become apparent as the description proceeds.

To the accomplishment of the above and related objects, my invention may be embodied in the forms illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that specific change may be made in the specific constructions illustrated and described, so long as the scope of the appended claims is not violated.

In the drawings:

FIG. 1 is a longitudinal sectional illustration of one embodiment of this invention;

FIG. 2 is a side elevation thereof;

FIG. 3 is a front elevation;

FIG. 4 is a top plan View;

FIG. 5 is an enlarged fragmentary illustration of the eccentric weights used on the aerator shaft; and

FIG. 6 is a fragmentary sectional illustration taken substantially along section line 66 of FIG. 1.

Referring to the drawings, the machine includes a stationary frame indicated generally by the reference numeral '1 formed for the most part of structural steel. The frame is box-like in shape, having an open interior in which is disposed a housing 12 of sheet steel or the like which is closed on all sides but open at the upper and lower ends. in the upper end portion of the housing 12 is a hopper, indicated generally by the reference numeral '14, this hopper having an inclined floor 16 and upstanding sides whichserve to guide sand into the hopper as it is fed through the mouth 18 thereof. Depending from the upper portion of this stationary frame 10 is a peripheral rim or flange 20 which extends inside the side walls of the hopper 14. To seal against the leakage or overflow of sand from the hopper, a flexible wall 22 formed of composition rubber belting or some similar suitably strong, flexible material is fastened to one portion of the flange 2t) and extended downwardly into firm engagement with the hopper floor 16, as shown in FIG. 1. This provides an eflective seal against sand leaking out of the hopper.

The hopper is provided with a relatively large discharge opening extending from the lowermost edge 24 of the hopper floor 16 to a point 26 located upwardly and away from the point 24. It will be noted from an exami nation of the drawings that this opening 24, 26 is quite large, so as to accommodate the relatively free flow of large quantities of sand contained in the hopper.

A valve or gate, indicated generally by the reference numeral 28, is movable to close and open the hopper opening 24, 26, as may be desired. This gate 28 in the illustrated embodiment is formed of an arcuately shaped piece of sheet steel (FIG. 6) which is reinforced along the lateral edges by suitable flanges 30, as shown more clearly in FIGS. 1 and 6.

Secured to the two flanges 30 are two arcuately shaped strips 32 of rubber or steel which project above the plate 23 far enough to enter, respectively, two arcuately shaped channels 34 which are mounted on the underside of the hopper 14- adjacent to the opening 24, 26. These channels 3,4 may be formed of strip steel suitably edge-welded to the hopper floor.

As shown more clearly in FIG. 1, a strip 36 of resilient, rubber-like material is clamped to the underside of the hopper floor 16 so as to project downwardly and beyond the point 24 of the hopper opening. This strip 36 is positioned to be engaged by the distal or inner end 38 of the gate 28 so as to provide a tight seal or closure against sand escaping from the hopper when the gate is closed. I The hopper is further sealed by means of another strip 40 of resilient material mounted on the depending flange 20 so as to slideably engage the upper surface of the gate 28. The two strips 22 and 40 may be made of the same material.

The arcuate shape of the gate 28 corresponds to the arc of a circle having a center at 4-2 which is the axis of horizontal shaft 44 journaled in suitable bearings 46 mounted on the stationary frame 10. Two suitable angle irons 48 secured to the shaft 44 are connected to the gate 28 whereupon the gate may be swung into and out of closed position, as may be desired.

The operation of the gate is preferably accomplished by means of a pneumatic cylinder 56 (FIG. 2) having a connection at its left-hand end to the frame 10 and at its right-hand end to an arm 52 which is secured to the shaft 44. Actuation of the cylinder 50 thereupon serves to swing the gate 28 either to the open or closed position, depending upon the operation desired.

The housing '12 is held in position inside the frame 10 by means of suitable shock or vibration mounts 54 which in the present instance are fabricated of relatively soft but strong rubber as blocks, these blocks 54 being mounted between angle irons 56 on the housing and suitable brackets 58 on the stationary frame 10. By means of this type mounting, the housing 12 is free to vibrate with respect to the stationary frame 10. Since the hopper '14 is actually a part of the housing 12, it thus becomes immediately apparent that in order to close properly the hopper discharge port 24, 26, some type of flexible or resilient seals such as 22, 36 and 40 are needed. This is true because the gate 28 is stationary, being fixed to the frame .10, while the hopper itself is free to vibrate with respect to the frame 10. Preferably, seals like 22 and 4%] are used on the remaining two opposite sides of the hopper, these seals depending from flange Zil.

A baflle plate or inclined deflector 60 is welded or otherwise suitably fastened to the inner wall of the housing 12 so as to lie in the position illustrated in FIG. 1; this position is opposite the hopper discharge port 24, 26.

Immediately beneath the hopper, and more particularly beneath the hopper port 24, 26, is located an aerator 62 (FIGS. 1 and 3). This aerator may be of conventional construction, in the illustrated embodiment including a plurality of rigid fingers 64 set at right angles with respect to each other and arranged in spaced, side-by-side relation, as shown in FIG. 3. These fingers 64, for example, may be formed of steel and have a thickness of one-eighth (Ms) inch and a width of one (1) inch; the length may vary, depending upon specific design requirements.

These fingers 64 are clamped by some suitable means onto a shaft 66 which is journaled in oppositely disposed bearings 68 mounted in the sides 70 of the housing 12 (FIG. 3). Between the bearings 68 and the aerator 62, and on the opposite ends of the aerator, are mounted two. eccentric weights 72, these weights being clamped to'the aerating shaft 66, as shown more clearly in FIG. 5. As the shaft 66 rotates, the weights 72 as well as the aerator 62 rotate therewith.

As seen in FIG. 3, the left-hand end of the aerating shaft 66 is connected to a flexible shaft coupling 74 which in turn is coupled to the output shaft 76 of an electric motor 78. The motor 78 is flexibly or shock mounted on a platform 80 rigidly fastened to the main frame 10. Operation of the motor serves to rotate the output shaft 76 and with it the flexible coupling 74, shaft 66, eccentric weights 72 and the aerator 62.

Across the open bottom end of the housing 12 is fastened a distributing screen 82 of a desired mesh size. This screen 82 is set at an angle as shown in FIG. 1 and is located directly beneath the aerator 62. Immediately beneath the screen 82 is a guide chute 84 which serves to guide sand sifted through the screen 82 to a desired location. Depending upon the size of the flask, the chute 84 may be omitted.

On the back side of the housing 12, or, in other words, on the right-hand side as viewed in FIG. 1, the portion of the housing adjacent the screen 82 is cut away to provide an opening 86, and in communication with this is a discharge chute 88 which is an extension of the screen 82. Particles which are too large to pass through the meshes of a screen 82 will flow through the opening 86 and outwardly from the discharge chute 88.

In operation, the frame is mounted on a rigid, stationary support. The mouth 18 of the hopper 14 is placed in communication with a supply of treated molding sand such that this supply maintains the hopper 14 filled at all times. A molding box or flask which is to be filled with molding sand is positioned beneath the screen 82 in readiness to receive sand.

At this stage, the actuator 50 is operated to swing the gate 28 clockwise, as viewed in FIG. 1. As the gate opens, an electrical switch (not shown) is automatically actuated to energize motor "78. As the gate continues to open, the motor 78 turns the aerator and the eccentric weights 72 at rated speed. Because of the eccentricity of the weights 72, the system is unbalanced, thereby causing the housing .12 to vibrate. This vibration is relative to the stationary frame 10 and also the motor 78; however, since the motor is coupled to the shaft 66 through flexible coupling 74 and is itself flexibly mounted on platform 80,

the radial or eccentric .vibration of the shaft 66 will be accommodated.

As the gate opens and the housing vibrates, sand flows from hopper 14 downwardly onto the 'bafiie plate 60 and onto the aerator 62. The aerator 62 revolves at a high rate of speed and cuts or knifes through the gravitating sand, thereby flufling and aerating the latter. This fluffing action renders the sand more fluid and, further, breaks up any lumps or clods which may have already compacted, the sand which reaches the screen 82 being of fine grain constituency and freely flowable through the screen. Any foreign particles or fragments which cannot pass through the screen 82 will gravitate through the opening 86 and out of the discharge chute 88.

Since the housing 12 is constantly vibrating, the sand will freely flow through the sifting screen 82 and downwardly into the mold box.

In the working embodiment of this invention, a vibratory excursion of the housing 12 relative to the stationary frame 10 is only one-sixteenth to one-fourth A) of an inch, thereby making it possible to obtain extreme accuracy in producing a well-defined flow of sand from the sieve 82 into a mold box (not shown). Thus, sand sifted from the machine may be limited almost to the precise confines of the mold box and thereby not wasted. When it is considered that the sand is reused many times and that the sand must be treated between each usage, this elimination of wastage means considerable savings in the cost of foundry operation.

When a mold box has been filled with sand and it is desired to terminate the sifting operation, the cylinder 50' is oppositely actuated for closing the gate 28. The motor 78 is provided with a brake 79 such that de-energization of the motor 78 results in almost instantaneous stopping of the vibrating action as well as the rotary motion of the aerator 62. Once the gate '28 is completely closed, further flow of sand from the hopper 14 is prevented.

The use of the gate 28 provides a means for accurately controlling the flow of sand from the hopper to the mold box. Furthermore, this accurate control coupled with the aerating function of the aerator 62 which further treats the sand and converts it into a fluid-like constituency produces an even and free flow of sand through the screen 82. This leads to an even distribution of compactable sand into the mold box.

While reducing wastage to a minimum, the machine is capable of operating faster than the usual manual operation, thereby providing another saving in cost of mold production.

Since the sand which emanates from the screen 82 is substantially fluid and freely flowable, its compression into a uniformly hard mold is greatly facilitated.

In the proper formation of a green sand mold, it is necessary that the surfaces of the mold, after the pattern has been withdrawn, be of equal hardness so that when the mold cavity is filled with molten metal it will uni.- formly resist the pressure of the metal, thus producing a casting that is true to the pattern. This is most difficult to attain when the pattern has large flat areas, deep pockets and deep vertical surfaces. Molding machines which squeeze or jolt (or both) the sand against the pattern are more or less successful in attaining a good mold, depending upon the quality of the sand, its moisture content, strength, toughness and flowability. The present invention improves the flowability or fluid-like quality of the sand as it rests in the flask just before it is subjected to jolting and/ or squeezing.

In the past and current practice, a device called a riddle is frequently used to impart fiowability. These consist primarily of a screen bottomed box through which the sand is sifted and sprinkled over the pattern. Riddles are shaken either by hand or by machine. In either case, it is a time-consuming operation, because the device must be separately filled and must use a relatively fine screen mesh to accomplish its purpose. Because of this, it has been too costly to introduce more than a thin layer .of riddled sand over the pattern. Then, when the bulk of sand is introduced by other means, such as a hand shovel or from an overhead chute, the heavy bulk of the added sand tends to pack the previously riddled sand, thus reducing its flowability and to that extent nullifying its benefits.

This invention renders it economically practical to fill the entire flask with a uniformly fiuffed, flowable sand of minimum density. Such sand, when jolted and squeezed, will give the mostuniforrn mold surface hardness, and will eliminate such casting defects as swells, rat-tails and ram-offs when these are due to lumpiness and poor flowability of the sand.

The screen shown in this invention is relatively coarse in mesh and is sloped to spread the sand evenly in the mold, rather than to sift or riddle the sand in the old sense. The flufling is done by the aerator blades, the mesh being employed to distribute the flufied sand into the mold flask evenly so it will be of uniform height in the flask prior to compressing.

If the device were mounted on the discharge end of a belt conveyor which supplied it with sand and if the conveyor were mounted on arms so that it could move horizontally in any direction, the screen cloth would not be needed. It is needed only when the machine supporting frame is immovable with respect to the mold flask.

It is common practice in foundries to fluff or aerate the sand as a final step in the preparation process. However, much or almost all of this beneficial Working is lost before the sand can be placed into the flask; bucket elevators, diverting plows mounted over belt conveyors, the long fall from the conveyor to the bin and the drop from the bin to the mold pattern all increase the density of the sand and to that extent nullify the benefits which could be obtained if it were possible to maintain the sand in its aerated condition until it is finally compressed in the mold. By making it practical to aerate the sand directly into the flask as it is being filled, this invention makes it possible to preserve the beneficial effects of aeration to produce better molds and better castings.

Also, since the old time-consuming practice of riddling or sifting is eliminated, lower mold production costs are achieved. Where it is desired to remove impurities such as sand pills or small matter detrimental to the casting process, a fine screen may be employed and the material removed is conveyed away from the mold flask.

What is claimed is:

:1. A flask-filling apparatus comprising a stationary supporting frame of box-like configuration, a housing having closed sides and open ends, said housing being disposed inside said frame with said ends vertically separated, a plurality of resilient cushion supports mounting said housing inside said frame, a hopper secured in the upper portion of said housing in registry with the adjacent open end, said hopper having an inclined floor and a discharge opening which extends away from the lowermost portion of said floor upwardly toward the mouth of said hopper, said opening lying in a plane that is inclined, said hopper having on the underside thereof two channels spaced apart and parallel on opposite sides of said opening, an arcuately shaped plate movable to close said opening, said plate having two side flanges disposed to move in said two channels respectively, a flexible seal in strip form mounted on said stationary frame and extending into said hopper to engage the upper side of said plate to prevent leakage of sand, a flexible seal on the bottom of said hopper and engageable with the lower end edge of said plate to further seal said opening when said plate is closed, a horizontally extending pivot shaft mounted on the outer side of said supporting frame, structure connecting said shaft to said plate for swinging the latter relative to said frame to open and close selectively said hopper opening, an actuator on said frame and connected to said plate for operating the latter, an aerator disposed inside said housing in'a position beneath said hopper opening, said aerator comprising a plurality of relatively thin outwardly extending rigid fingers mounted on a horizontal shaft in spaced side-by-side relation, said shaft having opposite ends journaled in the sides of said housing, two eccentric weights secured to the opposite end portions of said aerator shaft, a mounting platform rigidly secured to said supporting frame, a motor mounted on said platform, a flexible coupling connecting said aerator shaft to said motor whereby rotation imparted to said aerator shaft by said motor rotates said eccentric weights for vibrating said housing, a distributing screen over the lower open end of said housing, said screen being inclined, and a dischage opening in the bottom of said housing adjacent to the lowermost edge of said screen for discharging particles too large to pass through said screen.

2. A flask-filling apparatus comprising a stationary sup porting frame of box-like configuration, a housing having closed sides and open ends, said housing being disposed inside said frame with said ends vertically separated, a plurality of resilient cushion supports mounting said housing inside said frame, a hopper in the upper portion of said housing in registry with the adjacent open end, said hopper having an inclined floor and a discharge opening which extends away from the lowermost portion of said floor upwardly toward the mouth of said hopper, said opening lying in a plane that is inclined, said hopper having on the underside thereof two channels spaced apart and parallel on opposite sides of said opening, an arcuately shaped plate movable to close said opening, said plate having two side flanges disposed to move in said two channels respectively, a flexible seal in strip form mounted on said stationary frame and extending into said hopper to engage the upper side of said plate to prevent leakage of sand, a flexible seal on the bottom of said hopper and engageable with the lower end edge of said plate to further seal said opening when said plate is closed, a horizontally extending pivot shaft mounted on the outer side of said supporting frame, structure connecting said shaft to said plate for swinging the latter relative to said frame to open and close selectively said hopper opening, an actuator on said frame and connected to said plate for operating the latter, an aerator disposed inside said housing in a position beneath said hopper opening, said aerator comprising a plurality of outwardly extending rigid fingers mounted on a horizontal shaft having opposite ends journaled in the sides of said housing, two eccentric weights secured to the opposite end portions of said. aerator shaft, a mounting platform rigidly secured to said supporting frame, a motor mounted on said platform, a flexible coupling connecting said aerator shaft to said motor whereby rotation imparted to said aerator shaft by said motor rota-tes said eccentric weights for vibrating said housing, and a distributing screen over the lower open end of said housing.

3. A flash-filling apparatus comprising a stationary supporting frame of box-like configuration, a housing having closed sides and open ends, said housing being disposed inside said frame with said ends vertically separated, a plurality of resilient cushion supports mounting said housing inside said frame, a hopper in the upper portion of said housing in registry with the adjacent open end, said hopper having an inclined floor and a discharge opening which extends away from the lowermost portion of said floor upwardly toward the mouth of said hopper, said opening lying in a plane that is inclined, said hopper having on the underside thereof two channels spaced apart and parallel on opposite sides of said opening, an arcuately shaped plate movable to close said opening, said plate having two side flanges disposed to move in said two channels respectively, a flexible seal in strip form mounted on said stationary frame and extending into said hopper to engage the upper side of said plate to prevent leakage of sand, a flexible seal on the bottom of said hopper and engageable with the lower end edge of said plate to further seal said opening when said plate is closed, a horizontally extending pivot shaft mounted on the outer side of said supporting frame, structure connecting said shaft to said plate for swinging the latter relative to said frame to open and close selectively said hopper opening, an actuator on said frame and connected to said plate for operating the latter, an aerator disposed inside said housing in a position beneath said hopper opening, said aerator comprising a plurality of outwardly extending rigid fingers mounted on a horizontal rotatable shaft having opposite ends journaled in the sides of said housing, and two eccentric weights secured to the opposite end portions of said aerator shaft.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS 1,772,874 Meyer Aug. 12, 1930 1,962,734 Dupre June 12, 1934 2,171,115 Kiesskalt et a1 Aug. 29, 1939 2,412,425 Rawson Dec. 10, 1946 8 Erisman Oct. 26, 1948 John Nov. 19, 1957 FOREIGN PATENTS Germany Nov. 28, 1930 Germany Sept. 10, 1931 Great Britain I an. 24, 1951

Claims (1)

1. A FLASK-FILLING APPARATUS COMPRISING A STATIONARY SUPPORTING FRAME OF BOX-LIKE CONFIGURATION, A HOUSING HAVING CLOSED SIDES AND OPEN ENDS, SAID HOUSING BEING DISPOSED INSIDE SAID FRAME WITH SAID ENDS VERTICALLY SEPARATED, A PLURALITY OF RESILIENT CUSHION SUPPORTS MOUNTING SAID HOUSING INSIDE SAID FRAME, A HOPPER SECURED IN THE UPPER PORTION OF SAID HOUSING IN REGISTRY WITH THE ADJACENT OPEN END, SAID HOPPER HAVING AN INCLINED FLOOR AND A DISCHARGE OPENING WHICH EXTENDS AWAY FROM THE LOWERMOST PORTION OF SAID FLOOR UPWARDLY TOWARD THE MOUTH OF SAID HOPPER, SAID OPENING LYING IN A PLANE THAT IS INCLINED, SAID HOPPER HAVING ON THE UNDERSIDE THEREOF TWO CHANNELS SPACED APART AND PARALLEL ON OPPOSITE SIDES OF SAID OPENING, AN ARCUATELY SHAPED PLATE MOVABLE TO CLOSE SAID OPENING, SAID PLATE HAVING TWO SIDE FLANGES DISPOSED TO MOVE IN SAID TWO CHANNELS RESPECTIVELY, A FLEXIBLE SEAL IN STRIP FORM MOUNTED ON SAID STATIONARY FRAME AND EXTENDING INTO SAID HOPPER TO ENGAGE THE UPPER SIDE OF SAID PLATE TO PREVENT LEAKAGE OF SAND, A FLEXIBLE SEAL ON THE BOTTOM OF SAID HOPPER AND ENGAGEABLE WITH THE LOWER END EDGE OF SAID PLATE TO FURTHER SEAL SAID OPENING WHEN SAID PLATE IS CLOSED, A HORIZONTALLY EXTENDING PIVOT SHAFT MOUNTED ON

Images