US2386326A

US2386326A - Core box

Info

Publication number: US2386326A
Application number: US528877A
Authority: US
Inventors: John W Lowther
Original assignee: Kerotest Manufacturing Corp
Current assignee: Kerotest Manufacturing Corp
Priority date: 1944-03-31
Filing date: 1944-03-31
Publication date: 1945-10-09
Anticipated expiration: 1962-10-09

Description

Oct.9, 1945. WTHER 2,386,326

GORE Box Filed March 31, 1944 2 Sheets-Sheet l Jami wi zw hr Oct. 9, 1945. .Lw. LOWTHER 2,336,326

CORE BOX Filed Mafch :51, 1944 '2 Sheets-Sheet 2 ilfllmllllllllllllu INVENTOR -Ja]m WLan/t/zr- Patented Oct. 9, 1945 UNITED STATES PATENT OFFICE CORE Box John W. Lowther; Pittsburgh, Pa., assignor to Kerotest Manufacturing Company, Pittsburgh; Pa., a corporation of Pennsylvania Application March 31, 1944, Serial No. 528,877 7 Claims. (01. 22 13) My invention relates to core-boxes, particularly to core-boxes for making cores used in the casting of globe valves. v

The invention consists in certain new and useful improvements in core-box structure, whereby the production of cores may be accomplished more expeditiously and with greater accuracy.

The invention will be understood upon reference to the accompanying drawings, in which:

Figure 1 is a view in vertical or axial section of a globe valve of the conical seat type, the type in whose production a core formed in the corebox of this invention may be used;

Figure 2 is a view in side elevation of a core made in a core-box of the invention; 7

Figure 3 is a bottom view of the two component parts that are united to form the core;

Figure 4 is a view in end elevation of the core;

Figure 5 is a view inplan of one of the two complementary parts of a core-box which in exemplary way embodies the invention;

Figure 6 is a view of the'core-box part in section, on the plane VI-VI, Figure 5;

Figures 7 and 8 are views in elevation, one view shown at right angles to the other, of a certainmolding element of the core-box structure; and

Figures 9 and 10 are two views similar to Figures 7 and 8 of a certain guideway that cooperates with the molding element.

Referring to the drawings, the globe-valve structure comprises a housing or casing 2 of cast steel or other suitable metal. The casing is of spheroidal or ovate form, and is provided with the

usual flanges

5 and 6 that are engaged by complementary flanges carried by the pipe line or duct in which the globe-Valve is incorporated. Internally, the casing 2 includes a partition having a horizontal seat portion 1 that is ported, as at 8. The port 8 is circular as viewed in plan, and the rim of the port is machined, or a machined insert is provided, to receive a, valve element (not shown). The valve element is movable relatively to the seat to open and close the port 8 and thereby control the flow of fluid in the pipe line.

The complete globe-valve structure includes a bonnet that is secured to the usual flange 9, and the operating stemof the valve extends through the bonnet and carries the valve element. None of these latter parts of the conventional globevalve structure is illustrated herein. They are known items of valve construction and have no immediate bearing on the present invention. Sufiice it to note that internal partition of the valve casing includes a horizontal, ported seat potrion 1 that is integrated to the spheroidal side walls of the valve casing 2, by means of conically shaped webs or division wall portions 10 and H.

g The web portion l0 consists in a segment of an upwardly diverging conical shell which, located above the seat portion 1, extends from a point [2 of tangency with one side wall of the casing, through 180 about the vertical axis of the port 8, to a point of tangency with the sidewall of the casing that is located opposite to the point l2. In similar manner the web portion ll consists in the segment of a downwardly diverging conical shell that, located below the seat portion 1, extends from the point 12 through 180 on said axis, and together with the web portion Ill and the seat portion 1 completes the integral division wall or partition which, save for the port 8, entirely closes or blanks the inlet I, of the valve structure from the outlet 0. It will be understood that the valve casing with its flanges, and the partition 1, II], II comprise a unitary metal casting, the lines Illa. and Illb, indicating the manner in which the web I0 merges with each side wall oflthe valve casing, and the lines Na and lib afiording a similar indication with respect to the web II.

It will be understood that the external shape of the valve casing is determined by the matrixcast, while the internal form of the casing is determined by a core, such as the core 3 illustrated in Figures 2 and 4. The core is secured in the matrix of the mold, and the space formed by and between the surfaces of the matrix and the core body is identical in shape with the integral valve casing and its ported partition. The body of the core 3 includes cylindrical hubs a, b, and c, and the portions of such hubs which extend outwardly from the dotted lines L form no part of the metal-shaping matrix of the mold and core assembly, but provide the support for the core in place within the mold, it being understood that the mold is provided with cylindrical cavities that extend outwardly from the mold matrix to receive said support-affording portions of the core.

The body of the core includes recesses I00 and I is which are accurately shaped to form the seat and web portions 1, l0 and II in the cast body of the valve casing 2, while a central portion in the core body forms the port 8.

In practice, the core 3 is molded in two halves 3a and 3b, as shown in Figure 3, ofany suitable core-forming material. The half 3b is molded in Figures .5 and .6 the. element 2|; is arranged Opposing. relation toztherelementflil, andv the chamber 21a, in' which the guideway and guide; portions of element 2|: are. organized, is provided in the core-box body on theopposite side of the matrix from the chamber 21. a

.Whereas. the core-box is .in the main con.- structed of wood, the molding elements. 2 3 and 2 i and theirassociate parts 22, andifi'may be, and :advantageously are, constructed of. metal, preferably aluminum. 1 y Y By virtue of the structure described, the molding elements are not only removable from the molded core material in exactly the proper path to avoid impairment of the work, but they are rigidly supported in position of service in the mold. The engagement of the guide portions 22 with the guideways 2B is a snug sliding engagement that is preventative of any looseness of the Additionally, the

supported molding elements. arms 24 snugly fit in recesses provided therefor in the core-box body; the edges h of the Web portions 1 of the molding elements snugly engage the slots in the matrix Wall through which they extend; and the meeting ends of the two molding elements are overlapped and interengaged in a joint 2'. All of these features make for absolute security and rigidity of the molding elements, as is desired when core material is tamped into place within the matrix of the core-box. From the point i of interengagement of the two molding elements, each molding,

element extends through an arc of 90, while as already described the guide portions 22 extend through an arc that is of greater effective length.

The core half molded in the box is deposited upon a metal platen, and on such platen it is supported in an oven wherein it is baked and solidified, ready to be united with a similarly prepared complementary core half.

Within the terms of the appended claims various modifications may be utilized, without departing from the spirit of the invention herein disclosed.

I claim as my invention:

1. A core-box for producing one of two complementary core halves that, joined together, are

including a matrix, two curved molding elements extending into said matrix to form in the core half molded therein a recess and a core body portion for shaping cast metal to the form of said ported valve seat, a curved guideway in the corebox structure for each molding element, each molding element being provided with a curved guide portion for engagement with a guideway to support the molding element in proper position in said matrix, the guide portion of each molding element being movable longitudinally of the engaged guideway to move the supported molding element on the line of its curvature from said matrix.

2. A core-box for producing one of two complementary core halves that, joined together, are used in casting a globe-valve casing thatthas a valve seat with a port therein, said core-box including a matrix, two curved molding elements extending into said matrix to form in the core half molded therein a recess and a core body portion for shaping cast metal to the form of said ported valve seat, said molding elements meeting in overlapped engagement and extending from the point of engagement each through an arc of substantially 90, a curved guideway in-.ithe core-box structure for each molding .ele-: ment,. each molding element being provided with a curved guide portion for engagement withia. guideway to support the molding elementjin proper posit-ion in said matrix, the guide portion of eachmolding element being movable longitu-. dinally of the engaged guideway to move the supported molding element on the line of its .curva: ture from said matrix.

3..A core-box for producing one of. two.com-; plementary core halves that, joined together, are used casting .a' globe-valve casingv that. has a Valve seat with a port therein, said. core-box including a matrix, two curved molding elements extending into said matrix to form in the core half molded therein a recess and a core body portion for shaping cast metal to the form of said ported valve seat, a curved guideway in the core-box structure for each molding element, each molding element being provided with a curved guide portion for engagement with aguideway to support the molding element in proper position in said matrix, the guide portion of each molding element being movable longitudinally of the engaged guideway to move the supported molding element on the line of its curvature from said matrix, the eiiective arcuate extent of the engagement of each guide portion with its guideway being greater than the arcuate extent of the corresponding molding element,

, whereby the molding element in its movement is positively guided until it is completely removed from said matrix.

4. A core-box for producing one of two complementary core halves that, joined together, are used in casting a globe-valve casing that has a division wall between the valve inlet and outlet, the division Wall comprising a ported seat portion integrated to the Wall of the valve casing by two frusto-conical Webs each of substantially extent peripherally of the seat, with one web located on one side of the seat and the other web on the opposite side; said core-box including a matrix, two curved molding elements extending into said matrix to form in the core half molded therein a recess and a core body portion for shaping cast metal to the form of said division wall, a curved guideway in the core-box structure for eachmolding element, each molding element being provided with a curved guide portion for engagement with a guideway to support the molding element in proper position in said matrix, the guide portion of each molding element being movable longitudinally of the engaged guideway to move the molding element on the line of its curvature from said matrix.

5. A core-box or mold including a matrix, two molding elements each in the form of a segment of a conical shell, an arcuate guide secured to each of said molding elements, and two guide- Ways arranged in the core-box structure severally to receive said guides, with the molding elements supported in said matrix and with the cone axes of the molding elements arranged in alignment but with the divergence of the conical body of one molding element extending in opposite direction from that of the other, said guides being severally movable along said guideways in curved paths that are concentric with the aligned cone axes to remove the molding elements from said matrix.

62. A core-box or mold including a matrix, a molding element in the form of a segment of a shell of circular transverse section, an arcuate guide axially spaced from but concentric with theaxisnf revolution of the. shell, means for rigid ly securing said arcuateguideto said: shell; and a guide-Way in the core-box toreceive said guide,

therefrom but concentric with the axis of the conical body thereof, and two guideways arranged in the core-box structure severally to receive said guides, with the molding elementssupported in 7 said matrix and with the cone axes of the molding elements arranged in alignment but with the divergence of the conical body of one molding element extending in opposite direction from that of the other, said guides being severally movable along said guide-ways in curved paths that are concentric with the aligned. coneaxes to remove the molding elements from said matrix.

JOHN W. LO'WTHER.