US2266978A

US2266978A - Mold

Info

Publication number: US2266978A
Application number: US321525A
Authority: US
Inventors: John J Mader
Original assignee: Apex Electrical Manufacturing Co
Current assignee: Apex Electrical Manufacturing Co
Priority date: 1940-02-29
Filing date: 1940-02-29
Publication date: 1941-12-23
Anticipated expiration: 1958-12-23

Description

Dec. 23, 1941. Y 1A J, MADER l 2,266,978

MOLD

Filed Feb. 29, 1940 2 Sheets-Sheet' l u Ir 'In w INVENTOR. JOHN J. MADE/e,

trarne/v Dec. 23, 1941.

MOLD

Filed Feb. 29, 19440 2 Sheets-Sheet 2 1NVNT0R.. JOHN J. MADE/l2 Y B Ww/fa, fam/f .1.J. MADER 2,266,978

Patented Dec. 23, 1941 UNITED stars gir; orio-a MOLD John J. Mader, Parma, Ohio, assignor Vvtol'lhe Apex Electrical Manufacturing Company,

Cieveland, Ohio, a corporation of Ohio Application. February 29, 1940, Serial No. 321,525

4 `Glaims.

Itis a further object of my invention to pro-Y vide a method of making an aluminum agitator in a permanent mold wherein the molten metal is conducted to the agitator casting cavity in a manner which will rapidly ll the casting cavity with an even flow of metal free of impurities, gas pockets and turbulence.

It is a further object. of my invention to provide a method of making washing machine agitators having vanos wherein the molten metal is conducted into the agitator casting cavity solely through the vane portions thereof, so,- that the casting upon removal from the mold is free of gates in the base portion thereof and the casting is characterized as being free of hot spots, air pockets and the like.

It is a further object of my invention to provide ay method of making a washing machine agitator having a plurality of vanes wherein the molten metal is led into the casting cavity by gates along the edges of thevanes and such gates are` connected by a horizontally extending branch of a vertical pouring sprue.

It is a further object of my invention to provide a mold apparatus to carry out the methods of the preceding objects wherein the agitator is cast with its axis vertical and the base of the moldv forms the base of the casting cavity, and

such mold base is free of gates along the baseo the agitator.

Further objects and advantages relating to economies in manufacture and uniformity in castings will appear from the following description and appended drawings; wherein Figure 1 is a sectional elevation of an agitator mold made according to my invention;

Figure 2 is a plan view of the agitator mold;

Figure 3 is a plan view with partsv in section showing a casting made according tothe method and apparatus of my invention;

Figure 4 is an elevation of the agitator casting showing the gates and sprues attached;

Figure 5 is a plan view of an agitator casting showing a modified form of the invention;

Figure 6 illustrates a further modiiied form of,`

the invention; and l Figure 'Z is a sectional elevation taken. along. the lineA4 l-l of Figure. 6.

rEhe agitator type of washing machine has enjoyed wide use'and numerous methods have been proposed for casting the agitators of `aluminum in permanent` molds. Among the successful methods of casting such agitators is that method disclosed in the patent to Fahlman 1,770,368, wherein the agitator is cast in a vertical position with the-base of the agitator resting on the base of the mold, and wherein the molten metal isv conducted into the casting cavity through. a ring gate surroundingthe base of the casting cavity. This method, although generally productive of good castings, results in'a` castingrequiring a large volume of metal in the gate, which metal must be removed from the base of the agitator and the base machined throughout. its gate area. Since the gate and pouring sprues are scrap metal, the use of the Fahlman method results in considerable waste due to the arrangement and proportions required in the gate.

According to my invention, I propose to eliminate any gate around the periphery of the base of the agitator casting and thus reduce the volume of scrap metal and the attendant machining costs on` the base of the agitator following the removal of the gate.

I, have obtained the 'objects above enumerated by leading Vthe molten metal into the casting cavity in the vaned portions. thereof through relatively-small, vertically-disposed gates, so shaped and proportioned that the molten metal iiows quietly and smoothly into theA casting cavity. The gating arrangement. along the vanes of the agitator is so proportioned and arranged with respect to the pouring sprue and the casting cavity that any impurities which may Vbe carried in the molten metal are trapped in the gate and thevmolten metal is so conditioned prior to its entrance into the casting cavity that the resulting casting is free oi -hot spots, bubbles or otherdeects. Y v v My invention-contemplates the use of a permanent mold such as that .shown in Figure 1 of the drawings, wherein the base` 6 of the ymold is supported by a plurality of legs 'l and a plurality of movable mold sections 8, 8 and I0 are pivotally carried by the base' 6'. A, reciprocable core It projects upwardly through the center of the mold base 'E and the movement of the core H is controlled by'a shaft l2 having a rack I3 thereon at its lower end.` A horizontal shaftlll mounted in 'bosses I5 and i6 in the supporting structure` of the mold'is provivsied"wi-thl gear teethv |17 adapted to mesh with' the teethof the rack lf3/on the verticallyreciprocab1e core shaft I2, Movement of the core member II is thus effected by a inanual movement of the handle I8 producing rotation of the horizontal shaft I4. The movable core sections 8, 9 and I0 are shaped along their abutting faces to follow the contour of the spiral vanes 2|, 22 and 23 of the agitator casting indicated in its entirety as at 29.

The mold sections may be swung outwardly away from the base 6 of the mold upon the pivot pins 24 which are carried in depending brackets 25, integral with the mold base. The base of the mold 6 is conical in form so as to provide a conical base for the agitator and since the agitator includes 3 vanes, each of the three mold parts 8, 9 and I0 are cut away at their abutting surfaces to provide the casting cavities for the vanes.

In the preferred form of my invention, two

pouring sprues

21 and 28 are provided, a complementary half of the pouring sprue 21 being formed in each of the abutting surfaces of the mold sections 9 andV I8 and the complementary portions of the sprue 28 are formed in the abutting surfaces of the mold sections 8 and I0. The pouring sprues terminate at their lower ends at the top surface of the base 6 of the mold and extending laterally from the pouring sprue at a point spaced from the base of the mold is a gate comprising three adjoining sections 29, 39 and 3|. The section 29 is narrow in cross section and leads the molten metal into the section 30 which has a gre'ater vertical extent and a much lar-ger cross section than the section 29. The section 3| is relatively thin and one of the advantages of this construction is that it facilitates the removal of the gate and pouring sprue from the vane of the agitator casting.

When the mold has been conditioned by heating to appropriate casting temperature, the mold sections are secured to each other by mold clamps 33 and the molten metal introduced to the casting through the

pouring sprues

21 and 28. The rst metal out of the ladle into the sprue fills the lower end of the pouring sprue up to the restricted gate section 29. The restricted flow of the metal through section 29 eliminates turbulence and splashing resulting from the vertical drop of the metal down the pouring sprue. The

level of the molten metal rises in the sprue and in the lower end of the gate section 30 until it the molten metal'owing through the lower portion yof section 3| into the casting cavity is free of bubbles and impurities. Such metal, being heated by the molten'mass in the gate, fiows evenly downwardly from section 3| to ll the( 5.`

base portion of the casting cavity. As the casting cavity continues to fill, the metal rises evenly therein and the gate 29-30-3I carries sufficient molten metal at the proper temperature to compensate for the crystallization shrinkage characteristic of aluminum and other light metal alloys. The air in the casting cavity' is gradually forced out of the cavity through the parting lines of the mold sections as the metal rises in the GEW-ity. i.

After the casting has been poured and set, the' mold clamps 33 are freed of the mold sections and each mold section swung outwardly by means of the

handles

36 and 31 about the pivot axis 24. A rocking of the handle I8 effects a withdrawal of the core II to free the same of the casting. The casting, including the sprues and gates, is removed from the mold and the sprue and gate removed from the vane in the weakened or restricted section 3 I.

Although I have found that a three-vane agitator of the type illustrated may be satisfactorily Y poured with two pouring sprues and two gate Y, vcontinuous ring 54. 40

arrangements, I am aware that the pouring of other types of agitators may require additional gating arrangements. To facilitate the casting of agitators requiring additional gating metal, I have shown a modification in Figure 5 wherein a three-vane casting indicated in its entirety at 48 is provided with a gate of the type shown in the preferred form along each of the agitator vanes. Two of the gates, namely 4I and 42, are provided with pouring

sprues

43 and 44. The third gate 45 lacks a vertical pouring sprue but is connected to the pouring sprue 44 by `a branch 46 leading therefrom. The branch or cond-uit 46 connecting the gat-es 42 and 45 to each other is formed by an arcuate groove in the mold base as indicated in Figure 7. By this arrangement molten metal from the pouring sprue 44 flows laterally through the groove 45 around the base of the agitator to the gate 45. The gate 45 being proportioned to have the two restricted sections filled in the manner heretofore described in connection with the preferred embodiment.

A further modification of my invention is illustrated in Figure 6, wherein all three gates 5l, 52 and 53 are connected to each other by a Two pouring sprues indicated at and 56 are employed and metal from the pouring

sprues

55 and 56 may flow laterally to the gate 52. The gate 52 being proportioned and arranged like the gate of the preferred em- A bodiment, conditions and feeds the molten metal into the casting cavity in a manner like that described in connection with the preferred embodiment.

In all three forms of my invention, it will be observed that the base of the agitator casting is free of gates and requires no machining operations such as are required where the casting cavity is filled by introducing the molten metal around the base of the agitator.

It will also be observed that in the preferred I' embodiment of my invention, the scrap metal to be removed from the casting comprises only the two pouring sprues 21--28 and their associated gates. The reduction' in the amount of metal required for each casting and the reduction in the machining operations results in high speed production of sound castings.

Although I have shown and described three forms of my invention in considerable detail, it

.will be appreciated that modifications may be made therein without departing from the scope of my invention as defined in the following claims.

Having thus described my invention, what I claim is:

1. A permanent mold for casting aluminum agitators having a base portion and upstanding impeller vanes, said mold having a casting cavity with the agitator base portion thereof horizon- `tally disposed, a pouring sprue extending downvwardly from the top ofthe mold to the plane of said base portion and spaced laterally from said base portion, said base closing the lower end of said sprue, a single vertically disposed gate connecting said sprue and that portion of the casting cavity forming the vane, said gate comprising three sections, one section being a restricted section adjacent the sprue, a second section being a restricted section adjacent the vane and the third section being an enlarged section between the two restricted sections, said third section having a vertical extent greater than the vertical extent of the other two sections.

2. A permanent mold for casting aluminum washing machine agitators having a base and upstanding vanes comprising a mold base and a plurality of separable mold members recessed to define a casting cavity with the base portion of the agitator horizontally disposed, said mold members being further recessed to define a vertically disposed sprue cavity, said sprue cavity closed at its lower end by said base spaced laterally from the casting cavity and a vertically disposed gate between said sprue and a vane portion of said casting cavity, the juncture between said vane and gate being above the lower end of the sprue and above the base portion of that part of the casting cavity forming the base of the agitator, whereby impurities in the metal are trapped in the sprue and gate and the molten metal is conducted into the casting cavity without turbulence.

3. A permanent mold for casting aluminum agitators having a base and a plurality of upstanding impeller vanes, said mold having a casting cavity with the agitator base portion thereof horizontally disposed, a plurality of movable mold sections having abutting faces recessed to form a casting cavity for an impeller vane, said abutting faces being further recessed to provide a gate cavity, certain of the abutting faces of the mold sections being further recessed to provide pouring sprues and other of the abutting faces being free of pouring sprue recesses, a fixed mold section beneath said movable sections providing a support for the movable sections and forming the base of the agitator casting cavity, said xed mold section provided with a groove extending about the base of the agitator casting cavity to provide a passageway to conduct molten metal from the pouring sprues laterally to a gate cavity formed in said other abutting mold faces which are free of pouring sprues.

4. A permanent mold for aluminum agitators having a base portion and a plurality of upstanding impeller vanes comprising a fixed mold base and a plurality of movable mold sections mounted thereon, the number of movable mold sections corresponding to the number of impeller vanes on the agitator casting, all of the yabutting faces of the movable mold sections being recessed to provide vane portions of the casting cavity and gates along the vertical edges of said vanes, certain of the abutting faces of certain of the mold sections being further recessed to provide pouring sprues connected to said gates, and other of the abutting mold faces being free of pouring sprue recesses, an annular groove formed in the xed mold section connecting said pouring sprues and gates, whereby molten metal is conducted laterally from the bottom of the pouring sprues to said other abutting mold faces which are free of pouring sprue recesses.

JOHN J. MADER.