US2861306A - Casting apparatus - Google Patents

Description

MT WAGNER CASTING APPARATUS Nov. 25, 1958 2 SheetsPSheet 1 Filed March 12, 1956 CASTING APPARATUS Matthew Wagner, Burbank, Calif. Applicafion March 12, 1956, Serial No. 570,883

1 Claim. (Cl. 22-151) This invention relates generally to a casting apparatus and relates more particularly to a casting apparatus for manufacturing large metallic rings employed about the upper end of sewer openings. Such rings are commonly referred to as sewer rings and provide a finishing means for the tops of manholes, with portions thereof set flush with street paving surfaces and providing a receptacle for a manhole cover.

I-Ieretofore, sewer rings and other large types of castings have been manufactured using sand type casting processes requiring a considerable amount of time, effort and expense in the forming of the sand mold. Additionaliy, sand type molds provide a rough surface casting and can naturally only be used once. The time necessary to construct the mold, using suitable patterns and to allow for suitable cooling time for molten metal placed therein required the maintenance of foundrymen and considerable foundry space in order that production quantities of castings may be produced. In other words, several individual operators housed in a large foundry floor area have been required heretofore.

In addition, sand type castings develop a considerable amount of porosity that produces castings of inferior quality.

It is, accordingly, one important object of the present invention to provide a casting apparatus for manufacturing such castings as sewer rings, for example.

It is another important object of the present invention to provide an apparatus for manufacturing relatively large castings, wherein a permanent mold is provided, to gether with means for operating this mold.

A further object of this invention is to provide a permanent molding apparatus for manufacturing relatively large castings, without the use of expendable cores and the like.

A still further important object of this invention is to provide a permanent molding apparatus for producing relatively large castings in such a manner as to insure w porosity of the finished casting, reduce the need for expensive machining of the casting and insure quality products.

Still another object of the invention is to provide a permanent molding apparatus that is rapid and efficient in use, reliable in operation and with which casting time, manpower requirements and floor space necessities may be reduced to an absolute minimum commensurate with production requirements.

Other and further important objects of this invention Will become apparent from the disclosures in the following detailed specification, appended claim and accompanying drawings forming a part hereof and wherein:

Figure 1 is a top plan View of the present casting apparatus;

Fig. 2 is an elevational view, partially in section, and taken substantially as indicated by line 2-2, Fig. 1;

Fig. 3 is a partially sectional view similar to Fig. 2, showing parts in different positions;

Fig. 4 is a fragmentary sectional view through the pour- 2,861,306 Patented Nov. 25, 1958 ing basin, as taken substantially as indicated by line 4--4, Fig. 1; and

Fig. 5 is a schematic diagram illustrating operating controls for use with the present apparatus.

With reference to the drawings, the present apparatus includes a generally annular base 10, having a centrally disposed, slightly vertically tapered opening or aperture 11 therein. The base 10 may be supported in any suitable manner, such as for example, as by appropriate'legs 13. The base 10 also has radially disposed bracket portions 14 that extend from the outer periphery thereof and are formed integrally with the base for a purpose to be hereinafter more fully described.

The base 10 serves to support a movable segmented cope indicated generally at 15. The cope 15 includes a plurality of arcuate segments 16 that are radially slidably disposed thereon by means of outwardly extending tab portions 17 formed integrally with each cope segment 16 and cooperably disposed in radially disposed slots 18 in an upper surface 19 of the base 10. The slots or grooves 18 are tapered relative to a radian of the segmented sections of the cope in order to permit free radial movement of the cope segments and slight misalignment thereof when the tabs 17 are radially outer ends of the slots. The upper surface 19 of the base 10 is planar to provide for easy movement of the cope segment 16, while still maintaining precise alignment thereof. The inner annular edges of the cope segments 16 have their upper surfaces provided with annular inwardly directed recess 20, the outer annular edge of which is undercut as at 21. An inner annular edge surface 22 of the cope segments is spaced radially outwardly from a continuation of the annular opening 11 in the base and is slightly conical.

With reference primarily to Fig. 2, the base 10 is provided with an annular groove 23, adjacent the upper peripheral edge of the opening 11 that is counterbored' as at 24. The upper edge of the annular groove 23 normally communicates with a lower edge surface 25 of the cope segments.

The cope segments 16 have circumferential abutting surfaces 25, a radially inward portion thereof being circumferentially relieved as at 27 to provide a radial space between portions of the circumferential ends of the cope segments.

With reference primarily to Figs. 1 and 2, a core member 28 is positioned normally within the opening 11 in the base 10. The core 28 is generally annular and provided with an outer annular surface 30 that is slightly tapered in conformity to the conical taper of the opening 11 in the base 10. The upper surface 31 of the' core 28 normally extends slightly above an upper surface 32 of the cope segments 16. A lower surface 33 of the core 28 is adapted also to extend slightly below a lower surface 34 of the base 10.

It may thus be seen that when the core 28 is positioned as shown in Figs. 1 and 2, a space or cavity is defined between the core 28, the base 10 and the cope segments 16, this space being provided by the groove 20, radially outwardly spaced cope segment surfaces 22, the groove 23 and counterbore 24 in the base 10 and an outer surface 30 of the core 28. Additionally, the spaces defined between spaced circumferential ends 27 of the cope segments also communicate with the space defined between the core and the segments.

With reference primarily to Figs. 1 and 4, a pouring basin 35 is attached to an outer peripheral surface of one of the cope segments 16 and has upwardly extending side portions 36 that extend over the upper surface 32 of the cope segment. The pouring basin 35 is arranged with an open mouth ferentially with respect to the annular groove 20 in the 37 that is directed generally circum-' .from the upper position.

'3 cope segments 16, with which the mouth of the pouring basin communicates.

Thus, molten metal poured into the pouring basin 35 will be deliveredin a circumferentially directed fashion to the groove and will travel about this groove within the confines of the outer peripheral edge of the groove 20 and undercut 21, also running outwardly into the space defined between the cope edge 22 and the core outer surface and into the groove 23 and counterbore 24 in thebase. The circumferential directional movement of the molten metal within the confines described hereinbefore serves evenly to distribute the molten metal about the core 28 and to prevent the formation of any hot spots or other local heating with regard to the core or other components of the apparatus. The. molten metal also extends into the radial space defined between the cope segment ends 27. Thus a sewerring indicated at R is molded within the confines of the base, cope segments and core, with the upper surface of the ring R being unconfined and accordingly slightly roughened.

Each of the cope segments 16 has attached thereto a piston rod which extend radially outwardly therefrom to hydraulic cylinders 41, each of which are supported on the radially outwardly extending tabs 14 from the base 10. The core 28 is supported normally in a position within the base 10 by means of a piston rod 42 which extends outwardly from a central bottom area thereof, to a hydraulic cylinder 43. The hydraulic cylinder 43 may be carried by a platform 44 connected with the legs 13 of the base structure 10.

After molten metal is poured into the pouring basin 35 and thereafter into the space defined between the core, cope segments and base, slight solidification thereof occurs as this metal cools and the core 28 is withdrawn from its normal position, as shown in Fig. 2, to a lower position as shown in Fig. 3. The beveled outer surface 30 of the core 28 and the conical beveled surface of the opening 11 in the base serve to permit easy removal of the core Immediately thereafter, the various cope segments 16 are moved radially outwardly from the positions shown in Fig. 2 to the positions shown in Fig. 3, thus to' expose the sewer ring -R in such a manner as to permit removal thereof from the casting apparatus. Movement of the core 28 and the cope segments 16 may be accomplished by any suitable operative structure, such as for example, the hydraulic cylinders 41 and 43 that may be controlled by means of the hydraulic system set forth in Fig. 5.

As shown in the diagrammatic illustration of the hydraulic system in Fig. 5, hydraulic fluid is delivered from a sump to a pump'51 by means of a conduit 52 and from the pump 51 by way of a conduit 53 to a Y conduit 54 and thereafter to rotary valves 55 and 56. From the rotary valve 55, hydraulic fluid is delivered by way of a conduit 57 to one side of the cylinder 43, to move the piston rod 42 and the core attached thereto in a downward direction. Return fluid from the cylinder 43 is conducted by way of a conduit 58 through the rotary valve 55 and by way of a conduit 60 to the sump 50. Fluid delivered to the rotary valve 56 by way of the Y conduit 54 is delivered through a conduit 61 to a pair of branch conduits 62 and 63 and thereafter to one side of each of the cylinders 41, to move the piston rods 40 thereof and the cope segments 16 that are attached thereto in a radially outward direction. Return fluid from the cylinders 41 is conducted by way of branch conduits 64 and 65 to a conduit 66, to the rotary valve 56 and by way of a conduit 67 to the conduit 60 and thereafter back to the sump 50. When the rotary valves 55 and 56are moved to the position shown by the dotted lines therein, the direction of the fluid to both the cylinder .43 and cylinder 41 is reversed whereby to move the pistons and rods of these cylinders in opposite directions, again to position the cope segments and the Core as shown in Fig. 2. The pouring movement, downward movement of the core 28 and radially outward movement of the cope segments 16, together with the return of the core in an upward direction and radially inward movement of the cope segments comprises one complete cycle of the present apparatus, with the completed sewer ring R being removed during the open time of the core and cope.

Each of the cope segments 16 are provided with semicircular passages 70 therein, to which conduit connections 71 and 72 are connected. Additionally, the core 28 is provided with an internal cavity 73, having a centrally disposed partition 74, the cavity 73 having conduits 7S and 76 extending respectively thereto and therefrom. The base 10 is also provided with an annular passage 77 which is spaced radially outwardly from the opening 11 therein. This passage structure 77 has a conduit 78 extending thereto and the conduit 80 extending therefrom. The page 70 in the cope segments 16, the cavtiy 73 and thec ore 28 and the passage 77 in the base 10 serve to provide means for circulating a cooling fluid therein for controlling the temperature of these components when heated by molten metal poured therebctween. For this purpose, fluid is circulated from a sump 81, through a pump 82 and by way of conduits 82 and 83 to the conduits 71, 75 and 78. Return fluid from the conduits 72, 76 and 80 is returned by means of conduits 84 and 85 to the sump 81. Each of the conduits 71, 72, 75 and 76 may have attached thereto flexible lines in order to enable the necessary movement of both the core 28 and cope segments 16.

It may thus be seen that the present apparatus may be cycled as described hereinbefore in such a manner as rapidly to produce precision casting parts, with the base, cope segments and core being made from any suitable metallic material having a melting point either at or somewhat higher than the melting point of the molten material to be poured therein. By withdrawing the various confining structures from the molding, easy and rapid removal of the sewer ring may be accomplished without the necessity for utilizing expendable cores or like structures. Additionally, it is to be noted that relatively small floor area is required for maintaining high production of the sewer rings.

Having thus described the invention and the present embodiment thereof, it is desired to emphasize the fact that many modifications may be resorted to in a manner limited only by a just interpretation of the following claim.

I claim:

A permanent molding apparatus for sewer rings comprising, in combination: a generally annular base structure having a centrally disposed aperture therein; a generally cylindrical core movably disposed through said aperture, said core having an upper end; a segmented cope slidably disposed on said base structure and positioned normally to surround a portion of said core in spaced relationship thereto whereby to define an annular cavity therebetween, said core and said aperture having complementary generally conically tapered mating surfaces, segments of said cope being arcuate and having upper surfaces normally disposed vertically below said upper end of said core, said surface defining an unconfinedv open face molding surface; an additional cavity formed in said base structure and communicating with said first mentioned cavity; tapered radial groove means on said base structure for guiding said cope segments for radial movement thereof on said base structure and relative to said core, said core and said cope being angularly stationary relative to said base structure; a plurality of first hydraulic cylinders positioned on said base structure, each cope segment being operatively directly connected with one of said cylinders; a second hydraulic cylinder mounted on said base structure and connected with said core; means for simultaneously actuating said first hydraulic cylinders whereby to effect radial movement of said cope segments relative to said core; means for actuating said second hydraulic cylinder to effect longitudinal movement of said core in said aperture, said movement of said cope segments and said core acting to open said first mentioned cavity following disposition of molten metal therein whereby to permit removal of said sewer ring from said additional cavity; a pouring basin carried by one of said cope segments, said pouring basin having a molten metal discharge end positioned generally tangentially with respect to said annular cavity; and means for circulating cooling fluid through said base structure, cope segments and said core.

References Cited in the file of this patent UNITED STATES PATENTS Hall Sept. 14, Edlund Aug. 10, Lehman May 8, Carlson May 26, Bushnell Jan. 19, Brown Nov. 13, Wagner Nov. 20, Wagner Feb. 13, Kost Jan. 16, Bean et a1. Feb. 26,

Images