US2124529A - Pressure casting die - Google Patents

Description

July 26, 1938. N. LESTER ET AL' I PRESSURE CASTING DIE 5 Sheets-Sheet 1 Filed Feb. 1, 195e N. LESTER ET AL PRESSURE CASTING DIE July 26, 1938.

5 sheets-sheet4 2 Filed Feb. v 1, 1936 INVENTORS 'Qa ocescr/am l BY Ztl weiss;

rz'arz 6.

ATTORNEYS,

July 26, 193s.

N. LESTER ET Al.

PRESSURE CASTING DIE' 5 Sheets-,Sheet 3 Filed Feb. 1, 1936 INVENTOR July 26, 1938.

N. LESTER T AL PRESSURE CASTING' DIE Filed Feb. 1, 1936 By adria/16; @55 Y vATTORNEYS UWENTOR-Sl i July 26,1938. N. LESTER ETAL 2,124,529

PRESSURE CASTING DIE v Filed Feb. 1, 1936 5 Sheets-Sheet 5 if' if v\ J ,UQ

INVENTOR ATTORNEY Patented July 26,1938` APA'IEN'I' 4OFFICE PRESSURE CASTING DIE Nathan Lester, Cleveland Heights, and Adrian E.

Weiss, University City, Ohio, assignorsfby mesne assignments, of gineering Company,

one-half to Lester En- Cleveland, Ohio, a corporation of Ohio, and one-half to The Superior Die Casting Company, Cleveland, Ohio, a corpora tion of Ohio Application February 1,

9 Claims.

The present invention relates to an improved form of permanent mold or die construction adapted to be used in a pressure casting machine A wherein molten metal is forced under pressure into the die cavity. More particularly the invention pertains to aA novelconstruction for the core assembly of a pressure casting die in winch hollow articles such as an internal combustion engine piston, are cast. Y

The general object and nature of the invention is to provide a core assembly for such a casting die which is capable of automatic and high production operation. A further object of the invention is to co-relate .the movement of the core pieces making up the core assembly-with the opening and closing movement of the pressure casting dies. JStill another object is to provide a novel iorm of slidable interlock between the individual pieces of the core assembly. AdditionalJ objects and advantages shall become. apparent as the following description proceeds.

To the accomplishment or the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out inthe claims. l

The annexed drawings and the following description set forth in detail certain mechanism embodying the invention, such-disclosed -means constituting, however, but one of various mechanical forms in which the' principle of the invention may be used. y

In said annexed drawings:

Fig. 1 is a view taken uponb the face of one of the die blocks showing the core assembly embodying the principle of our invention in position thereon; Fig, 2 is a view taken upon a plane normal to that of Fig. 1, being sectioned substanf tially along line 2 2 of said ligure' andshowing the two die blocks in closed position; Fig. 3 is a sectional view taken along line 3 3 of Fig. 1; and Fig. 4 is a sectional View taken along line 4 4 of Fig. 1; Fig. 5 is a view taken upon the face of one of the die blocks showing an alternative form of core assembly wherein the parting faces of the core pieces areA parallel tothe parting face of the die blocks, as distinguished from. the assembly shown in Figs. 1 to 4 inclusive where the parting faces of the core pieces are-at right@ angles to the die block parting faces; Fig. 6 is a view taken normal to that of Fig. 5 and being sectioned substantially along line 6 6 of said iigure and showing the die blocks and cor'e assembly in closed position; Fig. 1 is a view similar to Fig. 6 but showing the die blocks and core assembly in open position; Fig. 8 is a sectional view 1936, Serial No. 61,844

taken substantially along line 8 8 of Fig. 5;.Fig. 9 is a sectional view taken substantiallyalong line 9 9 of Fig. 5; Flg.`10 is an enlarged detailed view of the assembled core pieces of the form of construction shown in Figs. 5 to 7; Fig. 11 is a sectional view taken upon a plane normal to that of Fig. Fig. 12 is a sectional view taken substantially along line I2 I2 of Fig. 10.

Now referring more particularly to the drawings, there are shown therein a die block I and a die block 2 whose opposed faces meet along (not shown) of a pressure casting machine such as is disclosed in our joint lcopending application Ser. No. 29,638, filed July 8, 1935. A pressure casting chamber or cylinder 4 and a measuring plunger cylinder 5 are located in the die blocks I and 2 respectively. A sprue opening 6 leads from the cylinders 4 and 5, along the parting line 3, to the die cavity 1. 'I'he outer walls of the die cavity 1 are formedcby the die halves 8 and 9 which are removably secured to the respective die blocks I and 2 by suitable fasteners Ill,E whereby such outer wall die halves 8 and .9 may be replaced,or,changed for the purpose of accommodating different sizes or patterns of castings.

In the present instance, the die cavity 1 is ,shown as being in the form for producing an internal combustion engine piston which conventionally consists of a head portion, askirt por-f tion, and l.internally extending wrist pin bosses II and I2. As best shown in Figs. 1 and 4, the core pins I3 and Ill extend through the walls of the die cavity 1 and as far as the ends of the bosses II and I2 respectively. The core pins I3 and I4 are respectively mounted upon slidable` guide blocks I5 and I6 which are in turn carri^d by the die block 2 and slidably locked thereto byg T-slots I1 and I8 respectively. Angularly inclined horns or pins 20 and 2l are mounted in the die block I and extend through complementary holes 20 and 2| in the guide blocks I5 and IB. Thus,lwhenthe die blocks I and 2 are moved into open position, the guide blocks l5 and I6 being carried by the die block 2, will travel outwardly with respect thereto and thereby draw the core pins I3 and I4 in the same direction and out of their position in the interior of the die cavity 1. It will be noted that the openings in the die block 2 in which the pins 20 and 2Ivare received, are enlarged as at I9 (Fig. 4) so that there is clearance for the outer ends of the pins 20 and 2| as the die blocks are opened and closed.

The inner walls of the die cavity 1 are formed the parting line 3. The die blocks I'and 2 are .adapted of course to be mounted upon die plates Aofy the die cavity 1 (th`e otter wall of the core pieces 22, 23 and 24) to the dove tail joint 25 is in aradial direction with respect to the axial center of the casting. In this manner the parting line of the core pieces 22, 23 and .24 adjacent the die cavity 1 is normal thereto and the pressure between.

exerted upo the core assembly of the casting die will tend to force the core pieces tightly together along the parting line so that the casting metal will not have anopportunity to be forced there- Those portions ofthe core pieces 22, 23 and 24 which do not form the core assembly proper extend outwardly beyond the die cavity 1 as indicated at 22', 23 and 24' respectively. 'I'he portion 22 of the central core piece 22 is connected to a draw bar 28 by means ofthe dowel pins 21. An inclined shoulder 28 is formed on the dra'w bar 28 and adapted to bear against a hardened metal insert 23 in the faceof the die block I. When the surface oi' the insert 23 bears against thevinclined shoulder 28 as the die blocks I and 2 are moved into closed position, the draw bar 28 together with the central core piece 22 is thus forced and held in a securely locked position. 'Ihe outer end of the draw bar 28 is slidably car-v ried in a guide block 38. A gear-rack 3I on one face of the draw bar 28 `is engaged by the gear teeth 32 on the shaft 33 journalled inrtlie guide block 30. Gears 34 on each end ofthe shaft 33 engage with idler gears 34 mounted upon the stub shafts 38. The idler gears 35l in turn engage -withi the gear racks 31 on, the bars 38 carried by the die block I. The guide block 38 is carried bythe die` block 2 and secured thereto. in suitable fashion such as by the plate 48 with fasteners 4I Y and 42 and the angular arm 43 with fasteners 44 and 45. 'I'hus it will. be seen that the gear rack bar 38 moves with the die block I and the guide block 38 moves with the die block 2. As the die blocks I and 2 are moved with respect to each other, the gear racks 31 will rotate the idler gears 35, gears 34, shaft 33, gear 32 and gear rack 3I with the result that the d'aw bar 28 will be moved inwardly and outward as the case may be with respect to the die cavity 1.

'Ihe outer portion '23' of the core piece 23 is mounted upon a movable base plate 58 by means of suitable fasteners in the drilled holes 45 and 48. The outer portion 24' of thecore piece 24 is carried by a guide block 41 and secured thereto (by suitable fasteners located in the drilled holes 4 8 and 48. The guide block 4 1 is slidably mounted in the movable base plate 58 and locked thereto by means of af slot as indicated at 5I and 52.v 'An angularly inclined horn or pin 54 is .mounted in i the die block 2 and received in a complementary' 1 movablebase plate 58 is carried by guide pins 55 hole 55 in the guide block 41.l As is shown in Fig. 3, the hole 55 also extends into the die block I for possible clearance of the end of the pin 54. 'I'he which are mounted in the die block .2. Ejector pins 58 connect the movable base plate 58 to the ejector (mechanism,` part of which is indicated atk 83. Thus, when the die blocks I and 2 are moved into open position andthe ejector pins 58 are actuated to move in` an upward direction with y' respecta F1g. 2, themovable base plate sa win in contact with and supported by only the core `casting machine. engage, with the gear toothed shaft 11, whichin be moved away from the face of the die block 2 and the pin 54 will cooperate with the hole 58 in the block 41 to move the latter, together with thecore piece 24 in an upward direction with respect l to Fig.y 3 and towardn the center of the casting.

The movable base plate 58 has a portion removed as indicated at 88, adjacent the pin 54 in order to provide the necessary' clearance. The structure oi' the apparatus embodying our invention having been described and the oper- -ation of its component parts partially set forth,

.. through the casting cylinder 4, thence throughthe sprue opening 8 to the diecavity 1. After such casting operation, the die blocks I and 2 g are moved'away from each other and the central core piece 22 is thereby drawn in a right hand direction with respect to Figs. 1 and 2, and out from between the core pieces 23 and 24leaving a vacant space.l SimultaneouslybI upon ,moving g apart oi' the die blocks I and 2, the wrist pin and core pieces I3 and I4 are also withdrawn from within the die cavity 1 as 'previously described. After the core pieces I3, I4 and 22 have' been withdrawn. the ejector pins 58 are `actuated to move the movable base plate 58.away from the die block 2 and .simultaneously the core piece 24 is moved intothe space vacated by the' central core piece 22 The resultant casting thereby-is piece 23 from which it may be conveniently lifted by the operator. 'I'he above described cycle .of operations is then reversed and the parts returned to their initial position ready for anotherpressure casting charge. In the modified form of construction illustrated inx Figs. 5 to l2 inclusive, the core pieces have been rotated through an angle of ,90 with respect to the position which they occupyin the form of construction just described in connection with Figs. l to 4. '-I'hat is to say, the parting ,faces ofl the core pieces are disposed in planes parallel to the parting faces of the die blocks.

The die blocks-.If and 2' and the die cavity 1', as shown in Figs. 5 and 6 are similar to those pre viously described, with the pressure casting cylin`' der 4'Jand the sprue opening 8' leading into the die cavity. A core pin 85 is mounted in the die block I and has a gear rackA engaging with the pinion 88. A manually operated crank for power operating means such as a hydraulic cylinder may be connected tothe pinionI 88 in the customary manner and by this means the core pin can be moved inwardly and outwardly of the die cavity 1'. yA second corepin 81 extends through the die block 2" and is permanently mounted uponthe ejector box 58.. v g

'I'he central core piece 58 together with the two outer core pieces 18 and 1I constitute the corel assembly for the piston casting.' The central core piece 18 is connected to al slide or guide member 12 which is carried'in the guide housing 13. The guide housing 13 is in turn supported by'the ilx'ed brackets 14 and 15, the latter being attached to 70 the base or frame (not shown) ofthe Apressure A ban-0f gear ranks 1s, 1s

turnv also engages with the gear rack 18. on the guide member-12. The gear` rack bars 18, 18 are The guide member 12 carries-an upwardly projecting block 18 which is adapted to move back 'and forth in 'the recess 88 in a second slide or guide member 8|. The guide'member 8| ,is connected to the outer core piece 16 by means of the lap joint as indicated at 88 and the dowel pins 84. The guide member 8| is also carried by the guide housing 12. Theblock 18 is adapted to abut against a shoulder 82 at the end of the recess 88 in the guide member 8|.

The outer core piece 1| is connected to and carried by the block 85 which in turn is mounted upon the ends of the pins 86. The pins 86, 86 have the enlarged collar portions 81, "which bear against the face of the block or base plate 88. T he ends of the pins 86, 86 extend into the ejector box as indicated at 86'.

The base plate 88 is engaged by the roller carrying pins 89 on the end of the levers 88. The

rollers on the end of the pins 89 are adapted to work in elongated slots 9| in the side oi' the block 88. The levers 88 are mounted upon a iixed shaft 92 carried by the guide housing 18. The outer ends or the right hand ends (with respect to Figs. 5 and 6) of the levers 98 have laterally extending pins 98 carrying the rollers 94 which in turn are adapted to operate in the cam track 85 in the side of the guide member 12.

A draw bar 86 carrying the gear rack 91 is slidably mounted in the block 88. A cover plate 98 extends over the top of the bar 86 and carries the sleeve 99 surrounding the core pin 61. The right hand end of the bar 86 carries a transversely extending pin |88 'with the rollers |88' adapted to travel in the slots |8| in the brackets |82 mounted upon the plate |88. The plate |88 is in turn carried by the ejector pins |84 and slidably engages with the guide pins |85.

The gear rack'91 on the bar` 86 engages with a gear toothed shaft |86 mounted in the base plate 88. The shaft |86 also engages with gear racks |81 on the, pins 86. The left hand end of the bar 86 is bifurcated or cut away asindicated at |88 in order toprovide clearance for the core pin 61. Y

A coil compression spring |88 is mounted betweenthe base plate 88 and the ejector block 68 and tends to force the block 88 towards the die block 2'.

A lock pin ||8 is carried by the die block I' and lits through apertures in the core pieces 68,.

18 and 1| for the purpose of securely locking the core assembly together during the metal casting operation.

The operation of the last described apparatus is as follows: After the metal charge has been introduced to the die lcavity 1' and through the sprue opening 6', the core pin 65'is withdrawn by operation of the pinion 66. 'Il'he die blocks I' and 2 are then moved to open position as shown in Fig. 7. Next, the rack bars 16 are operated to draw the central core piece 68 and guide member 12 outwardly. The rollers' 88 travelling in the cam track move in a downward direction with respect to Figs. 6 and '1, andoperate to rotate the levers '88 about their xed pivot 82 and to raise the left hand end of the levers 98 together with the base plate 88. As the base pla-te 88 thus goes in an upward direction inw the position indicated in Fig. 7, the core pin 61 is stripped by means of the sleeve 88 and the pins 88 carry the outer' core piece upwardly and into the space vacated by the central core piece shown in Fig. '1. At this position, the casting is siight drawing together or inward movement of 69.- The spring |89 holds the base plate 88 and its attached parts in this position. The guide member 12 continues to travel in a right hand' outward direction until the block 19 abuts against the shoulder 82 and also draws the slide or guidel 5 member 8|, together with the outer core piece 18 into the withdrawn position as shown in Fig. '7'.

The ejector pins |84 are then operated to carry the plate |88 away from or in an upward direction with respect to the ejector box 68. During such movement of the lplate |88, the vrollers |88 in the end of the draw bar 96 travel in a right hand direction in the slots |8| and thereby draw the bar 96 to the position shown in Fig. 7. During such right hand'movement of the draw bar 96. the gear rack 81 rotates the toothed shaft |86 which in turn moves lthe pins 86 in an upward direction until the\ outer core piece [1|, which now carries the casting, is in the position l lifted of! the core piece'1l, the cycle ofopera- Y tions reversed and the parts assume their original position ready to Irepeat the casting operation.

The form of construction of the interlock between the core pieces69, 18 and 1| is illustrated in detail in Figs. 10, 1l and 12. The purpose of the construction illustrated therein is to eiect a the outer core pieces 18 and 1| upon the with- Y drawal of the central core piece 69.- The central core piece 69 is longitudinally tapered from its free end to its xed end, as illustrated in Fig. 11, with the result that the meeting faces of the core pieces are slightly inclined. 'A dove tailed joint, as indicated at ||2 slidably locks the outer core pieces 18 and 1| to the central core piecel 68, and as the central core piece 69 is withdrawn from its position between the two outer core pieces, kthe latter are. moved inwardly or drawn together a distance equal to the extent ofA the longitudinal taper of the central core.piece 68. In actual practice this distance is preferably about one ten lthousandth of an inch. Thus the core pieces are forcibly moved away from the Ainner walls of the casting a slight distance sufficient to prevent any sticking, as the central core piece is withdrawn.

Although the above described embodimentsof our invention disclose but one die cavity, orl a 50 "single impression die, as it is known in practice, it should be obvious to those persons skilled in the art that more than one die cavity, such as a "double impression die,.could be used without transcending the scope of the invention. 65 Such a change would merely require'the addition of duplicate elements in the die block and corel assembly.

- Other modes o! applying the principle of our n inventionI may be employed instead of the one explained, change being made as regards` the mechanism herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

We therefore particularly point out and distinctly claim has our invention:` f l 1. In a casting die, the combination of sepa-l able die btocks, an ejector mechanism movable with respect to said die blocks, a core member for said die comprising acentral core piece Land. a pair oiouter corepiecs adapted to make an interlocking fit with said central piece; a guide meniber carrying saidcentral core piece, supporting means for .said guide member connected vms gto one orma die blocks, mecnapism connected .75

4 Y aiaasaa to said guide member and adapted to move saidcore pieces being connected to said base/plate,-

means for moving said last-named core piece with respect to said-base plate. and means for moving said base plate with respect to said last-v named die block.

2. In a casting die, the combination of separable die blocks, an ejector mechanism movable with respect to said die blocks, a core member comprising a central core piece and a pair of.

outer core pieces adapted to make an interlockinge-.nt with said central piece, 'a guide member carrying said central core piece, supporting means lfor said guide member connected to one otsaid die blocks, mechanism connecting said guide memberto said die blocks and adapted to v move said guide member outwardly with respect to said die up'n separation of said die blocks, a

guide plate carrying onev of said outer core pieces, a base plate connected tosaid ejector I, mechanism and movable with respect to one of 'ablymo said die blocks and having said guide plate slidted thereon, means for movingl said guide pla with respect to said lbase plate. and means for moving said base plate away from one ot said die blocks. 3. In a casting die, the combination of separable die blocks, an ejector-mechanism movablel with respect to said die blocks, a coremember ior'said die comprising-a central core piece and a pair of outer core pieces adapted to make an interlocking lit with said central piece, a guide member carrying said central core piece, supporting means for said guide member connected to one of said die blocks mechanism connecting said guide member to said die blocks and adapted to move said guide member outwardly from said die ,upon separation of said die blocks, a base plate connected to said ejector mechanism and moving said Abase plate away from said lastmovable with respect to one of lsaid die` blocks, a guide plate movably mounted on said base plate, one of said outer core pieces being carried by said guide plate, an angularly inclined' member extending outwardly from onev of said die blocks, said guide plate having an inclined jsurfac'e engaging with said inclined member, and

means for moving said base plate away from said last-named die block whereby said inclined member cooperating -with said inclined surface is adapted to move said guide plate with respect to said base plate.

4.. In a casting die, the combination of s'epafable die blocks, an elector mechanism movable with lipect to said die blocks, a core member for said die comprising a central core piece and a pair of outer core pieces adapted to make an interlocking nt with said central piece, a guide member carrying said central core piece, supporting means for said guide member connected to one of said die blocks, mechanism connecting said guide member to said Adie blocks and adapted to 'move said guide member outwardly from said die upon separation of said die blocks. a base plate connected to said ejector mechanism and onerot, said outer core pieces being carried by said guide plate, anvangularly inclined pin extending outwardly from oney of said1 die blocks, said guide plate having an inclined hole adapted to receive said'inclined pin,v and means for 'rable die blocks, an ejector mechanism movable 5 with respect to said die blocks, a. core member for said die comprising a central core piece and a pair of. outer core pieces adapted to makean interlocking iit\with said central piece, a guide member carrying said central core piece, sup- 1|)v porting means for said guide member connected to one of said die blocks, lmechanism connected to said guide member and adapted to move said guide member outwardly from said die upon separation of saiddie blocks, a base plate connected to said ejector mechanism and movable with respect to one oi said die blocks, one of said outer core pieces being connected to said base plate, 'and means connected to said guide member for moving said base plate.

6. In a casting die, the combination oi' separable die blocks, an ejector mechanism movable with respect to said die blocks. a'core member for said die' comprising a central core piece and a pair of `outer core pieces adapted to' make an 25 s I plate, means connected .to said guide member for moving said base plate, and means for moving said last-named core piece with respect to said base plate.

7. In 'a casting die, the combination of sep- 40 arable die blocks,- an ejector mechanism movable with respect to said die blocks. a core memv ber for said die comprising a central core piece and a pair 'oi outer core pieces adapted to make v an interlocking nt with said central piece, a guide member carrying said central core piece. alliiporting means i'o'r said guide member connected to one oi' said die blocks, mechanism connected to said guide member and adapted to move said` guide member outwardly from said die upon separation of said die blocks, a base plate connected to said ejector mechanism and movable with respect to one of saiddie blocks, one of said outer core pieces being connected tosaid base plate, means connectedto said guide member for moving said base plate. whereby said last-named core piece together with the casting is moved away from one of said die blocks, and means for moving said other outer core piece outwardly from said die. 60

8. In'a casting die,.the combination of'sefarable die blocks, an ejector mechanism m vable with respect to said die blocks, a corel member for said die comprising acentral core piece and a pair of outer core pieces-,adapted to make an interlocking -t with said central piece, a guide member carrying said central core piece, supporting means for said'guide member connected to one of said die blocks, mechanism connected to said guide member and adapted to move said y guide member outwardly from said die upon separation of said die blocks, a'base plate connected te said ejector mechanism and movable with respect -to one of said die blocks, one o! said outer core pieces being connected to )said base plate,

amasar means connected to said guide member ior moving said base plate.'whereby said last-named core piece together with the casting is moved away from lone of said die blocks, and a second guide member located parallel to and engaging with said mst-named guide member ior moving Asaid other outer core piece outwardly from said die.

9. In a 'casting die; the comhinationotseparable die blocks, an' ejector mechanism movable 'with respectl to said die blocks, acore member for said die comprising a central core piece and apair of outercore pieces adaptedto make an interlocking nt with said central pice, a guide member carrying said central cre piece, sup- 15 porting means for said guide member connected to one of said die blocks. mechanism connected to said guide member and adapted to move said guide member outwardly from said die upon separation o! said die blocks, a base plate connected to said ejector mechanism and movable with respect to one of said die blocks. oneo! said outer core pieces being connected to said base plate. means-connected to said guide member for moving said base plate, whereby said last-named core piece together `with the casting is moved away from one of said die blocks, means for moving said other outer core piece outwardly from said die, and means 'for moving the ilrst outer core` piece and casting with respect tp said base plate.

. NATHAN LES'IIR. ADRIAN E. WEISS.

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