US2645829A - Pattern for vertical casting systems - Google Patents

Description

y 1953 w. H. JOHNSON 2,645,829

PATTERN FOR VERTICAL CASTING SYSTEMS Filed May 4, 1950 2 INVENTOR WILLIAM H. JOHNSON BY a" ATTORNEYJ Patented July 21, 1953.

UNITED STATES PATENT OFFICE 2,645,829 r I l PATTERN FOR VERTICAL CASTING SYSTEMS William H'. Johnson, Washington, D. C. Application May 4, 1950, Serial No. 159,909

(Cl. 22-157) (Granted/under Title 35, U. s. Code (1952),

2 Claims.

sec. 266) This invention relates toimprovements in the casting of metals, more patricularly to new systems for the pouring of metal in vertical casting and to match plates for the molding of foundry cores which in the set up position in'the foundry flask delineate or embody the new pouring systems of the invention.

Vertical casting as'commonly carried out inthe foundry involves a system including a vertical conduit or sprue with which is connected aseries of horizontally arranged conduits, usually two, lying one above the other, called step gates, which lead into the casting cavity. The pouring system which is located in the foundry flask adjacent the casting cavity, is defin d by forms which carry on their opposing faces,a mirror half of the sprue and the step gates; In operation of the system,

the metal is poured into the sprue and enters through the first or lowermost step gate into the casting cavity. When the level of the metal in the casting cavity reaches the point of entry of'thez 1 next higher step gate, flow of the metal from the sprue into the casting cavity takes place through this step gate, also. This is known in the art as sequence flow of the metal into the'casting cavity.

It has the advantages of shortening the pouring time and tending to produce 1 sounder castings. However, with asingle known exception based'upon a particularmetal, experience has shown that sequence flow of the metal in vertical casting systems can be had only with two step gates no,

flow or only a dribbling of the metal into the casting cavity being had" through the third'step gate. In view of the advantages to be derived therefrom, it is obviously, desirable to have a pouring system in which sequence flow of metals generally can;

be had through threerather than only two step gates, especially for the. founding of the longer castings.

It is, accordingly, an object of the present inventionto provide an improved system for the pouring of metals generally in vertical casting in which sequence flow into the casting cavity can be had through three step gates.

It is a further object of the invention to provide match plates from which can be molded? foundry forms which when set up in 'the foundry flask define the metal pouring systems of the invention.

Other objects of the invention will become apparent from the description which follows:

Briefly stated, I have found that metals generally can be induced to flow sequentially through each of three step gates into the casting cavity of a vertical casting system by providing in combination, a vertical conduit or sprue, a reservoir connected therewith and with a second vertically 2' arranged conduit or reverse sprue,;and a-seriesof three step gates connected to the reverse sprue and leading into the casting cavity. a I In th other aspect of my invention I have'provided match plates for the new pouring systems from which, in the usual way, can be molded matching foundry cores-which in their juxtaposed or operative position in the foundryflaskv define or delineate the new pouring systems. These match plates carry'on a broad. face thereof, a raised design in half longitudinal section-of the new pouring systems,-the raised design taking the form of a series of interconnected bossesfin half longitudinal section of th several parts of, the pouring system.

The invention will be more fully understood by reference to the following description taken in conjunction with the accompanying drawing in which like parts carry like numerals and in which: Figure 1 is a perspectivev view of :a match plate carryinga raised design fora-pouring system in connected a reverse sprue 3. 4, 5 'and'G- are step.

gates connected with the reverse sprue 3 and leading-into the casting cavity 1 shown in conventionalized form. 1 I

Th sprues and step gates are of equal diameter. The reservoir 2. as shown, is. of circular crosssection but may be ofany other configuration found-suitable, such as'rectangular 0r.0b10id,'pr0- vided it has suflicient capacity to reduce to a substantial degree the momentum of the metal flowing into it from the sprue I. The depth of the reservoir should be at least equal in magnitude to'the-diameter of the sprue l and preferably is greater,for'example, two to three times greater. Th width of the reservoir may be of'about the same magnitude as its depth and the length thereof should be sufficient to at least accommodate the sprues I and 3 connected in side by side rela: tionship to the top of the reservoir, but preferably is slightly greater.

In operation of the pouring system shown in Figure 1A, the metal, for example, steel, is poured into the sprue l, filling the reservoir 2. The reservoir serves to substantially reduce the momentum of the metal arriving from the sprue I. The metal rises upwardly from the reservoir into flows from the reverse sprue 3 into the casting cavity 1 through step gate 6 -.to completecasting of the metal.

Figure 2A shows a pouring systems'imilarfir'iutached thereto, said short vertical boss having a length and depth equal to from twice to three times the magnitude of the diameter of said first vertical half-round boss, said tapered vertical half-round boss having a minimum cross-sec- .tion'al area equal to that 'of said first vertical all respects to that shown in Figure l awith the. exception that the reverse sprue 8 is"taperedin' cross-section and connected at its basezwith'the reservoir 2. The step gates 4, Sand S are connected to the vertical side 6 of the tapered re" The operation of the system is" verse sprue 8. the same as that of Figure 1A. The enlargement of the base of the reverse 'sp'rue 8 serves to further reduce the momentum of the metal whereby Spurting of the metal into the casting mold 1 through the second step gate -is minimized or avoided. At the top, the cross-sectional area of the tapered sprue B is equal to that of the sprue I and at the bottom it'can be from about two to four'times the same;

In Figure 1 match plate In is provided with a raised design in half longitudinal section of the pouring system shown in Figure 1A, and in Figure 2 match plate II is shown provided with a similar raised design of the pouring system of Figure 2A. The raised designs are constituted by a series of connected bosses which are identified with the respective'elements of the pouring systerns by means of like numerals. The match 7 plates may bemade of wood, metal or other suitable material'and the raised designprovided thereon in known manner. v

Since various modifications and changes may be made in the invention without departing from the spirit or the scope thereof, itis not intended that it shall be limited to the herein described specific embodiments thereof but only as is required' by the appended claims.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed is: i

1. A pattern plate for molding foundry pouring forms, said pattern plate having attached to half-round boss and a maximum cross-sectional area of from about two to four times the same,

a series of three horizontal bosses attached to said tapered vertical boss along the side thereof which is remote from the adjacent vertical 1 boss and so arranged therealong that the lowermost of the three is located at the lower end and 'the-hi'ghest' at the upper end thereof, and the second is located intermediate of the other two, each of said three horizontal bosses having a cr'oss sectional area equal to that of said first vertical half-round boss.

2. A foundry pattern for molding pouring forms, said pattern comprising. a system of solid elements having a'flat surface each of which lies in a common plane, said system of solid elements including a short vertical bar of generally'rectangular' cross section having its outer vertical edges rounded off-,a pair of adjacently disposed vertical half-cylinders, the first of which is longer than the second, the second is of upwardly tapering cross-section and both are of greater length than said short vertical bar, each of said pair of vertical half-cylinders being attached at its lower end to the upper horizontal face of said short vertical bar, said horizontal face having a width slightly greater than is necessary to accommodatethe ends of said pair of vertical halfcylinders attached thereto, .said short vertical bar having a length and depth equal to from twice to three times the magnitude of the diameter of said first vertical half-cylinder, 'saidtapered vertical half-cylinder having a minimum crosssectional area equal to'that of said first vertical half-cylinder and a maximum cross-sectional area of from about twotofour times the same.

a series of three horizontal half-"cylinders attached to said tapered vertical half-cylinder along the side thereof which is remote from the adjacent vertical half-cylinder andso arranged therealong that the lowermost of the three is al area equal to'that of said first vertical halfa broad face thereof a system of bosses including a a short vertical boss of generally'rectangular cross-section having its outer vertical edges rounded off, a pair of adjacentl disposed vertical half-round bosses, the first of which is longer than the second, the second is of upwardly tapering cross-section and both are of greater length than said short vertical boss, each of said pair of vertical bosses being attached at its lower end to the upper horizontal face of said short vertical boss, said horizontal face having a width slightly greater than is necessary to accommodate the ends of said pair of vertical bosses atcylinder.

WILLIAM H. JOHNSON.

References Cited in the file of this patent UNITED STATES PATENTS clusive, and 252.

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