Патент USA US2124998код для вставки
July ‘26,1938. 2,124,998 M. A. BECKMANN PERMANENT MOLD Filed June 18, 1936 J6 I W1: m r uz I "A1MM* ,W ‘N 13y - " Attorney‘ ' Patented July 26, UNITED STATES PATENT IOFFICE 2,124,998 ‘ PERMANENT 'MoLn' Melbourne r signor to Aluminum A. Beckmann, Industries, Cincinnati‘, Inc., Cincinnati. Ohio,‘ Ohio, a corporation of Ohio Application June is, 1936, Serial No. 85,946 ‘ 4 Claims. The present invention relates to a permanent ‘mold particularly adapted to cast pistons in aluminum alloys which pistons are described and shown in my co-pending ,applications, Serial to make a substantially closed mosaic over the mold cavity, except of course, for the pouring gates. These, beingconventional are not shown, their arrangement ‘being substantially as ' in United States Fatent. 1,585,893. Cores l3 are 5 Nuxéibers 79,309, 79,310 and,.79,311, ?ied May 12, also manipulated as in the patent referred to. 193 . c -- ~ , . -5 - The casting of pistons in permanent molds is complicated by the necessity of lifting out the cores bodily. In the ordinary piston, the pin Each core, except I3 is provided with an individ ual handle |6 for manual withdrawal. , Referring to Figure-4, the central core assem 10 bosses are the only obstacle to lifting out such ' bly. comprises a core I‘! of nearly rectangular l0, cores, but in, the pistons here considered,- the cross section. This is the largest core and the one which is last ‘inserted and ?rst withdrawn after casting. Flanking the core ll there are two irregularly shaped side cores l8. Abutting all three of the just mentioned cores there is a. 15 ject ‘matter of the invention. One of its ob-\ “butter?y core" |9,"so called because its cross jects-is to provide such an arrangement of cores( section looks from above like a butter?y minus the body. Another core 2|, known as-the bridge that a piston of my special kind' can. be pro duced expeditiously from a mold or the general core, because its function is to help form the 20 type described in the United States patent to bridge 24, shown in Figure 3, is contained within Schnobrich, No. 1,525,893 of February 10, 1925. the butter?y core. Its upper portion 20 as seen Another object is to provide means for keeping in Figure 2, is completely encircled by the core - bridge forms an additional obstacle; The means‘ provided for casting this bridge and for providing for the removal of‘thé cores entire 15 from about and within the bridge iorni the sub the thickness ofithe bridge metal in properr'e ‘I! so that it is ?rmly positioned, but its lower , - end 2| hangs free so \that the metal can ?ow 25 In ‘the accompanying drawing, Figure 1 is a around it. Accurate control of the shape and vertical cross section orv the mold with all or the, thickness oi the‘ bridge is thus'rendered possible cores in‘ place except the bridge core, which is because the core is aligned not only by the top shown above its proper place. VThe cores are’ ?ange l5 but also by a long-bearing surface 20 shown ‘in section along the line' |-.,-_| oi‘ Fig. 4._ cooperating with the core It. The former con 30 trols the depth and the latter the alignment. 3° Figure 2 shows all of the cores except the pis ton pin cores, assembled, partly in section on The core‘surfaces are all‘accuratelymachined the line 2-2 of Fig. '4. > in cast iron, so that close ?tting is, achieved. In operation the cores l8 are inserted ?rst in Figure 3 is a perspective‘ cross-sectional view of a piston to be cast in my mold. The rela- -. the empty mold; the piston pin hole cores l3 35 tion between Figures 2 and 3 is as-ii the cores which form‘the piston. pin holes 22 and the 35 ofFigure, 2 had'?rst been pulled out or the bosses 23 around them are then brought into po piston of Figure 3, and reassembled. immediately sition. Core i9 isthen inserted and the bridge core 2| slipped into it. Core i1 is now positioned a 4 ve. - - - “ Figure 4 is a cross section of the entire central ~ and the casting performed. I Ai'ter setting of ‘the metal, core 2| is usually . vIn Figure 1, I0 is the body of the niold, II is - ?rst pulled, then cores l1 and I9, although‘co're the ?oor and I2 is the mold cavity. This cavity. I‘! may be pulled ?rst; cores, l8 can then be is established in the form of an inverted internal .‘withdrawn by pulling them ?rst'to. the ‘middle combustion engine piston by a- seven‘ piece core ‘ of. the mold cavity until they clear the bosses, 45 _ ~ . ' 45 which may be considered ‘to be composed of two then lifting upward; kinds of pieces. These are the piston pin hole ‘ By having the bridge core suspended ‘in the cores l3 which extend into the mold cavity from butter?y core on a long, accurate bearing, _;even opposite sides, and the 'core pieces II, I8, I! and if the butter?y core should become somewhat 2|, shown assembled in ‘Figure 2, which extend misaligned'in relation to cores H or’ IS, the vertically from above- into the mold cavity. bridge casting would still be strong and accurate .40 core assembly taken‘ on the line 4-4 of Figure 2. These are preferably -?ve in number-but may ‘because no substantial displacement of core 2| in core I! is possibles be more or less insome cases. The- depending cores are each provided with I claimas my invention: 1 _ an upper ?ange l5 each of’ which-is so shaped as to tit and cooperate with the other ?anges l5 l. _A permanent-mold structure for making a internal combustion engine piston which com- 56 "alga-gees ‘ prises a moldbody two piston hole‘ ex tending into said mold body from opposite sides thereof, a ilvev piece core extending vertically down into said mold body, one or said core pieces being in plan, or butter?y shape and containing a second piece or the core, saidlatter piece being of‘ rounded triangular shape,.and held for a sub stantial portion or its length at'a small distance casting ‘structure composed of at least two core pieces, one core piece being contained within the other and spaced theretrom'over a portion of its - length and being extractable-theretrom-so that said containing'core‘may be withdrawn from the 5 mold. - - - I 4. A mold core for a permanent mold metal casting structure composed of at least‘ two core from its containing core. > pieces, one eel-e piece being contained within the 2. A permanent mold metal casting structure 7 other and spaced therefrom over a portion of its 10 10 comprising a mold body and av multiple piece length and being extractable therefrom so. that core ?tting into said body, one of saiducore said containing core may be withdrawn from the piecesxcontaining another, said contained piece‘ mold‘,_a portion of said containing piece being being held over a portion of its length at a dis tance from its containing core,_ and being ex- 7 cut out around said- contained piece to permit ‘ 15 molding material to -?o,w‘ therebetween. tractable therefrom so that said containing core may be withdrawn from the mold. ' - 3.~A mold. core for a permanent mold metal . mom A. nncmamz.