US1935549A

US1935549A - Apparatus for forming molds

Info

Publication number: US1935549A
Application number: US595898A
Authority: US
Inventors: Emery Howard; Irvine Andrew
Original assignee: Bohn Aluminum and Brass Corp
Current assignee: Bohn Aluminum and Brass Corp
Priority date: 1932-02-29
Filing date: 1932-02-29
Publication date: 1933-11-14
Anticipated expiration: 1950-11-14

Description

Nov. 14, 1933. H, Mx-:RY Er Al. 1,935,549

` APPARATUS FOR FORMING MOLDS Filed Feb. 29, 1932 2 Sheets-Sheet l /i g] la Z-.

ATTORNEYS Nov. 14, 1933.4 H, EMERY -r AL 1,935,549

APPARATUS FOR FORMING MOLDS Filed Feb. 29, 1932 2 Sheets-Sheet 2 y /f l @f z e '38 waff/.1w f w 28 a, @Y 30 WNW 33 \'//Z A l' INVENTORS ,44m/@www4 f ,lA

ATTORNEYs Patented Nov. 14, 1933 i I iJNiTl-:D STATES PATENT ortica* y Howard Emery and4 Andrew Irvine, Detroit,

Mich., assignors to Bohn Aluminum t Brass Corporation,` Detroit, Mich., a corporation of A Michigan 'Application FebruaryK 29, 1932. .Serial No.1595,398

14 claims. (o1. 22-'10s) This .invention relates generallyto molds and The foregoing jas Well as other objects will be refersV more particularly to Van improved apmade more apparent as this description proceeds,

paratuslfor forming molds. Y l @SlJeCallywhen consideredjin connection With Although the present invention may be em'- the accompanying drawings','v1herein: f 1 .5 ployed with facility in the manufacture of va- Figure l is alongitudinal sectional vievv throug G U rious articles, nevertheless, it nds. particular a mold forming the subject matter of the present use When employed in fashioning cylinder'heads invention; Y

for multi-cylinder internal combustion engines. Figure 2 is a cross sectional vievv taken sub- Wherein it is desirable toI form each of the comstantial'ly on the line 2-2of Figure 1; f

bustion chambers of accurate predetermined size Figure 3 is a fragmentary sectional View i1- 6e' and in addition to formthe Walls of these chamlustrating the cope section of the molding apbers of`uniformdensity. l l DMB/19115; v l Y i y The present invention contemplates the provi- Figure 4 1S a plan View Of'the drag flk IJIOl" sion of a mold which insures securing lthefo-reto compacting the molding material'therein;

1.5 going advantageous features' by employing per- Figure 5 is a cross sectional View Vtaken on 70 manent cores or metallic chills for forming the the line 5 5 of Figure 4'; A portions ofthe mold cavity defining the 'comn Figure 6 is a sectional View. taken on the line bustion chambers and by insuring accurate lou 6 5 .of Figure Ll; y 'v Vcation of these chills Withinl one of the mold `Figure 7 isa fragmentary sectional View illussections. v i e trating the manner in which the cope and drag 75 One'of the principal'obj'ects of this invention sections'of the mold are accurately located with i I resides in the novel means provided herein for respect to each other;l andr i e accurately locating the chills 'inamold box prior Figiire 8 is' a fragmentary sectional View taken to ramming the molding materialfwlthin the latsubstantially Von the line 8--8 ofFigure' 4.

. Ater so that upon completion of this section'of Referring novv to the drawings, itwill be noted'sfy the mold, the portions of the chills correspondthat VWe yhave illustratedv Ain Figure 1 a mold 10" ing to the dimension of the combustion chambers comprising a cope section ,ll and a drag'jsection VWill project beyond one surface kof the molding 12. Embedded Within theupper surfaoepf the material accurate predetermined distances. drag section in predetermined spaced relation to v A further advantageous featurefof `thepresent leach otherfis a'pluralityo-f chills 13^havingpor- *55 invention Which contributes materially to simtions projecting,predetermined distances above plifying and expediting production is attributed thejupperifaceof the drag section and cooperatf to those steps in thev method of fashioning theV ing/With the ,dry sandv core ll in the cope 'secmolds which consist in removing the asks from tion 'of ,themoldto'formthe portions of `the'niold the molds immediately afterthe ramming operacavity Ydefining the vcombustion chambersi' The 9 9 tion and subjecting the molds to a baking process i members i3 are accurately machined to conform which, in addition to increasing the efficiency of to the contour of the 'desired'oombuston chamthe resultant castings, also` permits handling the bers and are preferably formed of metal so as molds throughout the subsequent operations Vto chill the Walls ofthe *combustionV` chambers 4.0 Without the supporting .assistance of the flasks. and therebyV increase the density of thesegvvalls. 95

By virtue of the foregoing arrangement, the In casting cylinder heads, it is also highly deasks-are employed only during the time'the sirable to 4chill or increasejthe density of the mold is being rammed, with the result that a portions ofthecasting toloe subsequently drilled relatively small number of flasks are capable of for receiving the stud bolts and for accomplishproducing a comparatively largev number "of ing this result, a plurality of additional `chills 10U I molds. y y v 1'5 are ,embeddedr Within lthe drag opposite the In instances Where the flasks are removed as aforesaid portions ofthe `casting 'and iiush with specified above and the mold is formed of cope the top surface ofthe drag. Cooperating with and drag sections, it is highly desirable to prothe chills 15 to performy the above function is a v'vide some means yindependent of the flasks for plurality of risers 16 formed Within the cope sec- 1,05

` '55 the foregoing function is accomplished herein. In the method of fashion-ing the mold,- the accurately locating the cope and ldrag sections tion yof the mold and @fashioned to supply the relative to each otherl prior to the pouring op-Y m'aximumamount of metal kto the portions ofv eration, and, accordingly, another object of this the casting to lie/subsequently drilled for the invention resides in thernovel mannerin Which 'stud'bolts cope and drag sections are formed by compacting the molding material within suitable flasks by ramming apparatus, not shown herein, but which may be any one of a number of the well known designs. After the cope and drag sections of the mold have been completely formed in their respective flasks, the latter are removed and the aforesaid sections are thoroughly baked permitting subsequent handling of the same without the assistance of the flasks. The foregoing construction materially simplifies and expedites handling of the mold sections as well as reduces the cost of manufacture since a relatively few number of flasks are capable of producing a comparatively great number of molds in rapid succession.

In view of the fact that. the flasks are removed from the mold sections immediately after forming the same, it is desirable to provide some means for accurately locating the cope and drag sections of the mold with respect to each other prior to the pouring operation. This is accomplished in'providing a pair of pins 17 having cylindrical intermediate portions 18 and having oppositely tapered

end portions

19 and 20. The lower tapered ends 19 of the pins are fashioned to engage within correspondingly tapered openings formed in opposite ends of the drag section during the ramming operation while the upper ends of the pins project above the top surface 'of the latter section for engaging within suitn able annular washers 21 embedded within the cope section flush with the bottom surface of thelatter. The internal diameter of the washers is so determined with respect to the external diameter of the intermediate portions 18 of the pins as to snugly engage the latter and thereby prevent relative shifting of the cope and drag sections. After the cope and drag sections of the mold have been properly positioned in the manner outlined above, the pins are preferably removed from the mold by means of a suitable tool 22 insertable within the openings 19 in the cope and threaded for engagement with tapped openings in theupper ends of the pins.

inasmuch as the operation of an internal combustion engine is Amaterially affected by variations in volume of the various cylinders of the engine, it isl highly desirable tov uniformly fashion each of the combustion chambers to accurate predetermined dimensions and in order to accomplish this result without resorting to the costly,A method of machining the combustion chamber walls, it is necessary to accurately predetermine the location of the chills 13 in the dragrsection of the mold. The foregoing is accomplished herein by providing the drag mold flask 24 with a metallic plate 25 secured to the inner surface of the bottom wall 26V of the flask and formed with a plurality of openings 27 therethrough corresponding in number to the nurnber of chills 13 employed in the mold. The openingsr27 are spaced from each other predeter- Vmined distances accurately conforming to the spacing of the combustion chambers in the cylinder head and the dimension of these openings is such as to permit the portion of the chills 13 forming the inner walls of the combustion chambers to extend downwardly through the openings 27 into suitable recesses 28 formed in the bottom wall 26 of the flask. While from the Aprevious description it will beA observed that the openings 27 in the plate 25 serve to accurately space the chills 13 relative to each other, nevertheless, some means must be provided for supporting-the chills in the aforesaid openings so that the portions of the chills extending below the plate 25 conform exactly to the desired di-l mension of the combustion chambers to be ultimately formed. 1n the present instance, each of the chills are provided with marginal, flanges 23 forming continuations of the bottom surfaces thereof and fashioned to overlap the inner surfaces of the marginal edges of the openings 27 as clearlyshown in Figure 5. inasmuch as the pressures subjected to the molding material in the flask 2lby the ramming apparatus are transferred directly to the chills 13, there is a tendency for the latter to sag, and since sagging of the chills during the ramming operation materially aects the accuracyof the resulting combustion chambers, it is highly desirable to provide some means for eliminating any such tendency. This is accomplished herein by providing additional supporting means for the chills 13 in the form of a plurality of sets of pins for each chill. While the number of pins in each set may vary as desired, nevertheless, we prefer, in the present instance, to employ three pins in each set suitably spaced from each other to provide a threepoint support for each chill. These pins are designated in Figure e of the drawings by the

reference characters

30, 31 and 32 and project upwardly into Athe recesses 28 from al plate 33 secured to the underside of the flask; As shown in Figure 5 of the drawings, the pins are provided with reducedportions at the lower-ends thereof extending through suitable openings formed in the plate, 33 and forming shoulders 34 engageable with the upper surface of the plate 33 for determining the length of the Vpins projecting above the plate. Owing to the irregular contour or the chills 1.3, the length of lli) the portion of each pin projecting upwardlyA from the plate 33 may vary in accordance with the portion of thechill engaged thereby, but in each instance the aforesaid lengthl is predetermined so that the pins cooperate with the plate 25 to support the chills. The spacing of the openings in the plate 33 through which the reduced ends of the pins project determines the spacing of thelatter and/the same are rigidly secured tol the plate 33 by nuts 35 threaded upon the ends of the pins. in this connection, it is to be understood that suitable shims are provided` on the pins between the shoulders and plate `33 so as to permit varying the length of the pins projecting above the openings by keither removing or inserting additional shims depending upon i the adjustment desired.

In order to provide for checking the cylinder head casting to determine whether the same has warped in the mold, each of the chills 13 is formed with a depression 38 having flat walls 39 arranged to engage the pin 3i) of each set when thechills 13 are located in the drag flask. The pins 30 are fashioned to locate the flat surfaces in a common plane substantially parallel portons'will be Vcoi-respondingly displaced. The

If the casting has been prop" fr taperedl upper ends of 4the pinsvlS extending 'into conditionA of the' `casting may Vbe readily calculated by selecting vone of the hat wall portions of the bosses and determiningjthe positions of the remaining wall portions relative thereto.

The plate 25, in addition to :locating the chills 13 with respect to each other, also forms a support for the chills l5 and 'for thetapered pins 38".

As shown in Figure 4 of the drawings, the front andrear rows of chills 1'5 are' accurately positioned upon the plate '25 by means'of lpins 39 projecting upwardly from the aforesaid plate at i predetermined points and engageable withsuitable recesses formed in the oase portions of the chills 15'. While'the center rowof chills 15 may be similarly positioned,` if desired, nevertheless, it is kfound vthat in actual practice, these chills may be located with sunicient accuracy by the `combustion chamber chills 13, and, accordingly, we

have illustrated Vtheformer chills as VYbeing so positioned.

The tapered pins 38' serve toform the tapered openings in opposite ends of vthe drag section for receiving the tapered portions 19 of the pins 18 in the manner and for the purpose Ahereinbefore set forth. The lower ends of the pins 38 are provided with reduced portions 40 extending through suitable openings formed in the bottom of the drag ask and threaded as at fil for attachment to the bottom' plate 33 of said iiask.V The reduced portions aforesaid of the pins form vannular shoulders 42 on the'latter f: of the mold, Vthe chills 13 and 15 are accurately positioned upon the inner wail of the'drag mold iasky 24'in the manner previouslydescribed, and molding-,material is compactedl within the flask by anysuitable apparatus. vUpon'completion ofthe ramming operation, a suitable plate is placed upon the top of the drag flask and ie latter is inverted to position .the chillsuppermost. Thev ask 24, together with the pins 38',

is then removed and the mold section introduced to a baking process. After the 'latterprocesa the vpins 18 are inserted within the openings inthe" drag section of` vthe Vmold kprovided `by the pins `38' andthe core llifisipositionedfin the gvusual l manner on the drag section.

' The' cope sectionrof the mold is preferably fashioned `simultaneously With the dragfsection and is formed in accordance with the usual practice with a mold cavity therein cooperating with the core le to formfthe outer walls of the `casting. A plurality of riser openings are alsoformed A' in the cope section during the `ramming operationfor the purpose specified above andfaddi- "tional openings are formed in yopposite ends thereof for receiving the upper ends of the pins 18. The lattei` openings are produced by tapered vpins 51 projecting upwardly from the bottom the openings in the cope, formed bythe pins '51, through the washers 21. The pins 18 are then removed by the tool 22 andthe molten metal poured into the mold through suitable spaces provided'for this purpose. After the mold has been ypoured as stated'above, the same isV permitted to cool whereupon it is broken up and the resulting lcasting -suitably machined. i

What weA claim as our invention is:

1. Apparatus for forming amold section having a metal chill member, `comprising `a flask fashioned to receive molding material and having a bottom wall provided with a recess therein for receiving a portion of said metal chill member, and means carried Aby said bottom wall for engaging the portion aforesaid'of said chill for supporting lthe same in predetermined relation to said bottom wall.

2. Apparatus for forming a'mold section having a vmetal chill member, comprising Va flaskV fashioned to receive lmolding material and having a bottom wall provided with a recess therein for receiving a portion of said metal chill member, means for supporting the metal chill member vin the flask with the portion aforesaid thereof in predetermined relation to the bottom Wall of the flask including a lateral flange on said chill member fashioned to overlap the marginal edge Y portions of said recess, and a member carried bythe bottom wall of said flask and engageable with the portion of said chill extending into the recess to form an additional support for said chill.

3. Apparatus for forming a mold -section havkg ing a metal chill member,v comprising a flask.

fashioned to receive molding material and having va bottom wall provided with a recess therein forreceiving a portion of 'said metal chill member, andV means' for supporting the'metal chill "member inthe flask with the portion aforesaid thereof in predetermined relation to the bottom wall of the fiask including a plurality of members carried by said flask and engagablewith the chill at spaced points. Y Y

A. Apparatus for forming a mold section having a metal chilll 'memben comprising-1ay flask fashioned to receive molding materialandfhaving ya bottom Wall provided with an Openingtherethrough vfor receiving a portion of said chill member, a closure member extending across the lower end of -said opening, and means for supporting the metal chill member Vin the'a'sk with the portionaforesaid thereof in predetermined relation to the inner surface of the bottom wallA of theiiask including a member extending upwardly fro-m said closure member and engageable with the adjacent face of the chillmember.

5; Apparatus'for forming a mold section having a metal ychill member, -comprising aV ask fashioned to receive molding material and 'having a bottom wall provided with an-opening-therethrouglrfor receiving a portion of said chill member, a closure member extending :across the lower Vend of saidV opening, and a plurality-fof members extending upwardly predetermined distances from the closure member into the recess for engaging the adjacent face of the chill at laterally spaced points to Support the latter in the flask with the portions aforesaid thereof in accurate predetermined relation to the inner surface of the flask.

`6. 'Apparatus for forming a mold'section hav-v' rte ' pins extending upwardly from the closure meming a bottomwall provided with a recess therein for receiving a portion of said metal chill member, means for supporting the metal chillmember in the flask Withthe portion aforesaid thereof in predetermined relation to the inner surface of the flask including a marginal flange projecting laterally from the chill and fashioned to overlap the inner surfaces of the marginal edges of said recess,and means located within said the portion aforesaid thereof in predetermined relation to the inner surface of the bottom wall of the flask including a marginal fiange projecting laterally from said chill in overlapping relation with the inner surfaces of the bottom wall of the flask surrounding opening Vand a memberv secured to said closure within said recess for engaging the adjacent face of thechill.

S. Apparatus for forming a mold section having a metal chill member, comprising a flash fashioned'to` receive moldingr material andhaving a bottom wall provided with an opening therethrough for receiving a portion of said chill member, a closure member extending across the lower end ofv said opening, and moans for supporting the metal chill member in the flask with the portion aforesaid thereof in predetermined relation tothe inner surface of the bottom wall of the flask including a plurality of adjustable ber into said recess' for engaging the adjacent face of the chill at spaced points.

9. Apparatus for forming a mold section having a plurality of metal chill members, comprising a flask fashioned to receive molding material and having a bottom Wall provided with a plurality of spaced recesses therein for receiving portionsof aA corresponding number of chills, means for accurately locating said chills with respect to each other, and means carried by the flask and extending into said recesses for engaging the chills to accurately supportv the latter within the iiasl; in predetermined relation to saidbottom wall.

10. Apparatus forforming a mold section having a plurality of metal chill members comprising a flask fashioned to receive molding material and having a bottom wall provided with a plurality, of spaced recesses therein for receiving portions of a corresponding number of chills, means for accurately locatingsaid chills with respect to each other comprising a plate secured to the inner surface of the bottom Wall of said y flask and having openings therethrough regisvextending predetermined distances beyond sa accurately receive the portions aforesaid of the chills, and means carried rby the flask and extending into said recesses for engaging the chills to accurately support the latter within the ask in predetermined relation to said plate.

' 11. Apparatus for forming a mold section hav- Vthe ask 'with the portions aforesaid thereof in predetermined relation to the inner surface of said plate including marginal flanges projecting laterally from said chills and fashioned to overlap the innersurfaces ofthe plate surrounding the` openings therethrough, and meansvlo'cated within each of said recesses below the`portions of the chills therein and engageable with the adjacent faces of the latter for cooperating with said flanges in accurately supporting the chills relative to said plate.

l2. Apparatus for forming a mold section having a metal chill member, comprising a flask fashioned to receive molding material vand having a bottom wall apertured to receive a portion of the chill member, and mean'sfor accuratelyv supporting the chill member in predetericc mined relation to the inner surface 'of said botiis aforesaid of the mold section., and means other c than said wall for supporting the chill in accu-v rate predetermined relationship to the inner surface of the Wall during the formation of Asaid mold section. Y j

14. Apparatus for forming a mold section having a plurality of spaced chill members supported on one surface thereof with portions lof the chills id surface, comprising a flask fashionedto receive molding material and having a bottom wall aperturedA to receive the-projecting portions of the chill members, meansfor accurately locating the chill members With respect to each other,

and means for ksupporting the chill members with 1 the projecting portions in accurate predetermined relation to the inner surface of said wall during the formation of the mold section.

HOWARD EMERY. ANDREW ERVINE.

ics Y