US2810942A - Pressure die casting machines - Google Patents

Description

Oct. 29, 1957 L. SAIVES PRESSURE DIE CASTING MACHINES Filed Nov. 22, 1955 2 Sheets-Sheet 1 Oct. 29, 1957 L. sAivEs PRESSURE DIE CASTING MACHINES 2 Sheets-Sheet 2 Filed Nov. 22, 1955 United States Pate PRESSURE DIE CASTING MACHINES Leon Saives, Billancourt, France, assignor to Regie Nationale des Usines Renault & Societe des Hauts- Fourneaux et Forges dAllevard, Bill-ancourt, France Application November 22, 1955, Serial No. 548,516 Claims priority, application France August 28, 1952 Claims. (Cl. 22-93) This application is a continuation-in-part of my pending application Serial No. 370,845, now Patent No. 2,791,- 014, granted May 7, 1957.

The present invention relates to pressure die casting machines and more particularly to machines for casting ferrous metals and is concerned with certain improvements in these machines for extracting the core, the casting and the chill mold.

It is an object of the invention to provide improved means for extracting the cores which may serve as cooling devices, then to eject the casting or castings and to eject the dies, all in a properly timed sequence.

Other and more detailed objects of the invention will become apparent from the following detailed description and the drawing, in which:

Fig. 1 is a sectional view of the injection cylinder and one of the mold assemblies;

Fig. 2 is a schematic top view of the machine showing one of the molds in section;

Fig. 3 is a sectional view of the jack.

The pressure casting machine represented in the attached drawing is a multiple machine which permits the simultaneous casting of four pieces from a single injection cylinder 4 arranged in the center of a group of four molds and their attached members, which are designated with a, b, c, d, in Fig. 2.

On a subfoundation e rests a base 2 and on it the upper mobile plate 1 of the press, the joining plane being assumed here to be at the level of the joining plane of the mold. This plate comprises four bushes 25 of which only one is visible in Fig. 1, and covers, when the plate is lowered, four stud guides 26 fixed on the base 2. This base supports a cylinder 6 which is closed by a piston 7, provided with a sheet metal tightening cup 8, whose piston rod 9 guided in a sleeve 10 is controlled by a hydraulic cylinder 11 which is partly represented.

The upper plate 1 holds the upper dies 12 and the cores 14 (only one die and one core being visible in Fig. 1). A gudgeon 27 connects elements 12 and 1.

The base 2 holds the lower dies 13 whose joining plane with the dies 12 is assumed horizontal and which are likewise immobilized by a gudgeon 27a. A core 15 is fixed by a bayonet coupling 15a to the end of rod 19 guided in a bore 19a of the base 2. This rod 19 supports a piston 36 sliding in a corresponding bore 36a of the base 2. The bore which is closed at its lower end by a tight cover 21 is traversed in a tight manner by a lower extension 19b of the rod 19 below the piston 36. The cover 21 supports a bushing 24 which can turn around its axis on a stop ring 35. The rod 1% holds in its lower part, a pin 23 sliding in opposite longitudinal grooves 24a of the bushing 24 which connects the rod 1% in rotation with said bushing.

The bushing 24 has a lateral extension 31 which can be actuated by a jack 22 by compressed air, for example. The rod 19 at its end is integral with a flange 18 in the form of a cross. A ring sliding freely in a bore 32 of the base 2 coaxial with the rod 19 holds four ejec- 2,810,942 Patented Oct. 29, 1957 tors 17 maintained in their seats 17a. This ring 20 comprises two groups of inner lugs 33, 34 each cutting at its level a female cross corresponding to the flange 18. A similar device is provided at the upper end in the mobile plate lot the press, to extract the core 14, but it is neither illustrated nor described since it is exactly the same as the device described above.

The extracting device operates as follows: At the end of the casting operadon the upper plate 1 of the press and the base 2 are still applied against each other, the injection pistons 5 and the obturator 4 are in the position shown, the pieces 16 are cast, and the flange with its projections are oriented with regard to the notched ring as shown in Fig. 2. In order to extract the core, the upper plate 1 is raised (by a hydraulic system which is not shown) to uncover the casting 16. There is then introduced Water under pressure through the conduit 37 above the piston 36 which ensures the descent of the latter and the extraction of the core 15 from the piece 16 and from the die 13. Then, in order to eject the casting 16 from the lower jack 22, the flange 18 is adjusted so that it can pass under the action of the piston 19 through the openings separating the lugs 34 (Fig. 2) to come between the two tiers 33, 34 of the cross. Then, by means of the jack, operating the handle 31 of the bushing 24 which entrains through the pin 23 the rods 1% and 19, flange 18 is turned so that it coincides with the lugs 33, and water is injected under pressure through the conduit 38 under the piston 36 which raises the ring 20 entrained by the flange 18, thus ensuring the rising of the ejectors 17 which push the casting 16 out of the lower die 13.

If it is desired to eject the die 13, gudgeon 27a is retracted keeping the ring 20 in its high position. Water under pressure is then introduced on the upper face of the piston 36 after having regulated, by means of the jack 22, the orientation of the flange 18 so that it can pass under the lugs 34 of said ring. By turning the cross 18 so that the studs of the flange pass under the lugs 34, and by introducing water under the piston 36, we make the flange push the ring 20, which in turn pushes the die 13, ejecting it out of its seat in the base 2.

What I claim and desire to secure by Letters Patent is:

l. A core-extracting device for a pressure-casting machine, more particularly for ferrous metals, said machine comprising at least one mold consisting of two dies applied against each other, a vertically movable upper plate supporting one of said dies, a fixed base in engagement with the other of said dies, said base having a bore therein, an injection cylinder having a piston in said base, at least one core beng provided in the interior of the mold and adapted to cooperate with said dies, said core-extracting device comprising a hydraulically controlled cylinder having a piston therein, said piston having a rod connected thereto and said rod being connected to the core, a studded flange carried'by said rod, a notched ring coaxial with said rod and slidable in said bore in the base of the machine, said ring having notches selectively permitting and preventing the passage of the studs of said flange upon reciprocation of said piston and its rod, depending on the orientation of the flange about its axis, ejection plungers for the casting engaged by said notched ring, and means for controlling the orientation of the flange about its axis in such manner that, in one orientation, the studs of the flange pass through the notches of the notched ring without entraining the latter to permit the piston to be displaced in a direction away from the mold, thereby causing extraction of the core from the mold.

2. A core-extracting device according to claim 1, wherein said means for orienting the flange is efiective to move the flange so that its studs engage the notched ring and whereby when the piston is moved in the di-' rection of the mold following extraction of the core, the notched ring is engaged and the ejection plungers attached thereto are moved in said direction of the mold to eject the casting.

"3. A pressure-casting machine according to claim' 2,

wherein said piston is movable toward the mold 'a distance suficient to cause the notchedring to' engage the die supported by the, fixed base and eject it from the fixed base of the machine.

4. A pressure-casting machine having an injection cylinder and a plurality of molds: conneeted thereto each of s'aid molds having a core-extracting device as defined in claim 1;

V 5. A pressure die-casting machine for stripping a castr' ing from a chill mold containing a core, comprisinga notched collar, the notches in said collar being arranged so that'they selectively permit and prevent the passage of said projecting studs depending on the angular position of the piston, a jack for turning the piston in such a manner that, with a suitable orientation, the studs pass freely through the notches of the notched collar for one rotational displacement of the piston while, 'foranother rotational displacement of the piston, the studs contact the notched collar and drive it in an axial direction together with theiejection plungers'for ejecting the cast- 7 ing. n References Citedin the file of this patent UNITEDSTATES PATENTS J 1,941,811 Morin Jan. 2, 1934 1,961,941 Pack June 5, 1934 2,485,283 Guelph Oct. 18, 1949 2,558,027 Wilson June 26, 1951 2,583,093 Emmert et al. Jan. 22,1952" 2,657,440 Myers Nov. 3, 1953

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