US1575498A - Multipart core - Google Patents

Description

March 2 1926. 1,575,498

A. B. NORTON MULTIPART CORE Filed Feb. 29- 1924 2 Sheets-Sheet 1 AT RNEYS March 2 1926." 1,575,498

A. B. NORTON MULTIPART GORE Filed Feb 29, 1924 2 Sheets-Sheet 2 11 9Q5 Z 6 f 1y: 1 II I v INVENTOR 41 wmwm BY Wvhztfifi I ATTORNEYS ?atented Mar. 2, M25,

ALLEN IB. NORTON, 0F CLEVELAND, @HIU, ASSIGNOB 1Y0 ALUMUIM UQMIE'ANY Oil ERICA, 0F PITTSBURGH, PENNSYLVANIA, A CORIPGRATIQN 0F PENNSYLVANM MULTEX'ART CORE.

Application filed February Q9, 1924. serial We. 695,901.

To all 107mm it may concern:

Be it known that l, ALLEN P). NORTON, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented certain new and useful improvements in Multipart Cores, of which the following is a specification.

This invention relates to molds for casting hollow cup shaped metallic articles, particularly internal combustion engine pistons and is primarily concerned with a five part core for a piston having an inwardly extending annular flange at the open end thereof.

Une object of the invention is to provide a new and improved live pant core capable of forming a hollow cupshaped. casting having opposite inwardly extending projections and an annular inwardly extending flange at or adjacent to the open end of the casting.

A further object is to provide a five part core for a piston having chordal boss carrying webs and anannular inwardly projecting flange at or adjacent to the open end of the piston,

Other objects will be pointed out herein after.

Prior to my invention permanent cores for making cup shaped castings, particularly pistons, having inwardly extending projections, as cross webs carrying bosses, and an inwardly extending annular flange at or adjacent to the open end. of the casting' consisted of not less than seven sections, so far as I am aware. Such cores comprise relatively smallsections which are susceptible to the influences of the high temperatures of the molten metal and often warp and thereby become unfit for use or substantially so.

I have discovered, however, that a five part core can be made for such castings which will function satisfactorily in male ing' castings of the foregoing description both as regards easy removability from the castin and resistance to warping. A core embo ying my invention and capable of performing as described will be set forth hereinafter, the details of the construction and configuration and arrangement ofparts of such core being fully described and claimed.

In the drawings forming a part of this specification and attached hereto.

Figure 1 is a "fragmentary view through a mold equipped with a core constructed in accordance with my invention, the casting being shown in section, and the core in elevation.

Figure 2 is a fragmentary cross sectional view taken substantially on line2-2 of Figure 1.

Figure 3 is a fragmentary view similar to Figure 2, but showing the core partly removed from the casting.

Figures 4 and 5 are respectively fragmentary cross sectional views taken on lines 4-42 and 5-5 of Figure 3.

lln the drawings 1 have chosen to show tragg mentarily the well known piston molds of the type more completely described in the patent to Joseph ll. Hamburg, No. 1,996,588 issued March 4, 1919, inasmuch as my present invention is confined more particularly to the core.

In the drawings, 1 indicates a conven tional mold base and 2 the mold bodies or mold halves which have their meeting faces suitably recessed to form the side walls of a casting cavity 3, the end wall of which cavity is formed by the top surface 4 of the base member 1. Core pins 5 passing through suitable holes 6 in the mold halves 2 project into the casting cavity 3 where they may engage with the main core, later to be described, to form hollow wrist pin bosses 7 on the casting,

Molten metal is led into the casting cavity 3 through a suitable gate 8 which may include a feeder cavity 9.

The core is indicated as an entirety by 10. It comprises five sections, including two oppositely disposed side sections 11 a center section 12 and two oppositely disposed outer sections 13 arranged on either side of the center section 12 and between the side sections 11'. Sections 12 and 13 may thus constitute a row of sections extending across the core between the side sections 11..

The assembled core is provided on its outer surface and at a point remote from the inner end thereof, namely, the end which forms the inner end wall. of the casting cavity, with an annular recess 14 adapted totorm a oorrespondin ly shaped inwardl extended flange or prqection 15st or ad jacent to the open end of the casting. The outer surface of the assembled core is also provided with oppositely disposed bom recesses 16, each recess being preferably formed in a side section 11. It will be understood that when the assembled core 10 is in position in the casting cavity 3 and the core pins 5 are assembled therewith as shown in Figure 2, hollow bosses 7 will be formed on the casting in the recesses 16 and about the core pins 5.

Each side section 11 is provided with a longitudinally extending enlargement or projecting portion 17 on its inner surface, the said portion being sufficiently extended toward the center of the core, so that the boss recess 16 will not extend entirely through the section and being sufliciently wide so as to surround the boss recess 16 on all lateral sides. In the particular form of casting 18 shown in the accompanying drawings, 1 have provided chordal boss carrying webs 19 which extend more or less parallel to the diameter of the piston located at right angles to a line joining the bosses. To provide for such chordal' webs 19, I suitably recess the core sections 11 as at 20, the recesses 20 and 16 merging into one another to form the web 19 and boss 7 integral.

The center section is provided with longitudinally extending recesses 21 corresponding in size and shape with the portions 17 with which they cooperate. The thickness of the center section 12 is determined by the thickness of sections 11, its thickest parts being along the longitudinal edges at either side of the recesses 21. The outer sections 13 have a maximum width which is substantially the same as the maximum thickness of the center section 12 and'each engages both side sections 11 and center section 12. It will be observed that in this particular form of core, the minimum cross sectional areas or the smallest dimensions of the side sections 11 which extend from side to side on a transverse plane through the core and in the middle of the bosses are substantially uniform and of the maximum permissible size. For example see Fi re 5 which is a section taken substantia y on line 5-5 of Figure 3 where the relative sizes and uniform nature of cross sections is illustrated. In such piston this uniformity of cross section is important since it apparently enables the sections 11 to resist satisfactorily the tendency to warp.

In the operation of my improved core the parts thereof are assembled in the mold and supported in the castingcavity by means of outstandin flanges 22 at the outer end of the core w hich rests upon the top of the mold members 2. Center section 12 is rovided with similar flanges 23 to rest an be supported on the top of the remainin core sections as will be understood by those s illed in the art. When the mold has been closed, molten metal is led into the casting cavity 3 through the gate 8 and as soon as the same has solidified therein, the mold sections are released slightly, the center section 12 is lifted longitudinally out of the castin then outer sections 13 are moved radial y inwardly of the piston until they clear the flange 15 or even until they contact with the raised portions 17 of the side sections 11, after which they may be withdrawn longitudinally from the casting. The side sections 11 are next removed, preferably one at a time, by first moving the same radially inward until the boss has been released from the boss recess and then the section is tilted with the outer end across the casting until clear of all projecting parts on the casting, after which the section is removed from the casting.

It will be observed that I have provided a five part core which can be used to cast a piston having inwardly extending bosses and boss carrying cross webs, and an annular flange near the open end of the casting; and furthermore, that I have provided a core for a piston having chordal boss carrying webs which is resistant to warpage due to the high heat of the metal being cast. 7

Having thus described my invention, what I desire to secure by Letters Patent is defined in what is'claimed.

What is claimed is:

1. A five part core comprising two 0 positely disposed side sections, each forme on its inner surface with a centrally located longitudinally extendin raised portion and a boss recess in each si e section extending into the said raised portion and being only sli htly less in width and depth than the wi th and depth of the said raised rtion, a center section between the said slde sections extending on either side of the said raised portions, and two outer sections aligned with the said center section between the said side sections.

2. A five part core comprisin two oppositely disposed side sections, an two outer sections and a center section constituting a row of three sections therebetween, the said side sections each having a longitudinally extending projection on its inner surface, the said center section having recesses on opposite sides thereof to receive e said projections of the side sections, the said outer sections bein substantially as wi as the maximum thickness of the center section.

3. A five part core, provided with an annular recess in its exterior surface remote from the inner end, comprisin two oppositely disposed side sections, an two outer sections and a center section constituti a row of three sections between the si e sections, the said side sections each having a longitudinally extending projection on its inner surface and a boss recess extending into the said projection, the said center having recesses on opposite sides thereof to receive the said projections of the side sections.

4. A five part core, for a piston having chordal boss carrying walls, comprising two oppositely disposed side sections, each having its outer surfaces cut away to form a recess for a chordal boss carrying Web, and each having a projection on its inner surface opposite the said boss recess; and a row of three sections aligned between the said side sections, one of said three sections being recessed to conform to and receive the projections of the said side sections.

5. A five part core, for a piston having chordal boss carrying walls and an annular inwardly extending flange at or adjacent to the open end thereof, comprisin two oppositely disposed side sections eac having its outer surfaces cut away to form a recess for a chordal boss carrying Web and each having a projection on its inner surface opposite the said boss recess; and a row of three sections aligned between the said side sections, one of said. three sections being recessed to conform to and receive the projections of the said side sections, the assembled core being provided with an annular recess remote from the inner end thereof,

I 6. A five part core, for a iston, comprising two oppositely dispose side sectlons,

each provided with aboss recess and each having a substantially uniform cross sectional area on a transverse plane through the boss recess; and three sections aligned between and cooperating with the said side sections.

7, A five part core, for a piston, comprising two oppositely disposed side sections, each side section having a projection on its inner surface and a boss recess on the outer surface extending thereinto, the cross sectional area of each said section being substantially uniform on a transverse plane through the boss recess; and three sections aligned between and cooperating with the said side sections.

8. A five part core, for a piston, comprising two oppositely disposed side sections, each side section having a projection on its inner surface and a boss recess on the outer surface extendin thereinto the cross sectional area being su stantially uniform on a transverse plane through the boss recess, a center section engaging the inner surfaces ofthe said side sections and ex tending on either side of the said projections, and two outer sections of substantially the same width as the center section on opposite sides of the center section between the said side sections.

In testimony whereof I hereunto aflix m signature this 18th day of February, 19

ALLEN B.,NORTON."

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