US2464051A

US2464051A - Method of forming and ejecting die castings

Info

Publication number: US2464051A
Application number: US537472A
Authority: US
Inventors: Louis H Morin
Original assignee: Individual
Current assignee: Individual
Priority date: 1944-05-26
Filing date: 1944-05-26
Publication date: 1949-03-08
Anticipated expiration: 1966-03-08

Description

Patented Mar. 8, 1949 OFFICE METHOD OF FORMING AND EJECTING DIE CASTINGS Louis H. Morin, Bronx, N. Y.

Application May 26, 1944, Serial No. 537,472

8 Claims. 1

This invention relates to the formation of die castings, such for example, as scoops on a mounting tape in forming separable fastener stringers. More particularly, the invention relates to a novel method of arranging cavities or impressions in the dies movable toward and from each other in a common plane so that after a casting has been formed in the cavities or impressions, separation of said dies will operate to automatically eject the castings from the cavities or impressions, moving the castings at right angles to the line of movement of the dies in this operation. Still more particularly, the invention deals with the formation of castings having angularly disposed wall portions extending divergingly from the longitudinal center of the castings or from the parting line of the dies when the latter are in closed position, and in utilizing these surfaces in cooperation with the walls of the cavities of the dies forming such surfaces in ejecting the castings and moving them relatively to the dies. The novel features of the invention will be best understood from the following descriptions when taken together with the accompanying drawing, in which certain embodiments of the invention are disclosed, and in which the separate parts are designated by suitable reference characters in each of the views; and in which:

Fig. 1 is a sectional view through the coupling end portion of a few scoops of a stringer, showing a pair of dies used in castingone of the scoops on the stringer tape.

Figs. 2, 3 and 4 are views similar to ig. 1, showing different positions of the dies in separation thereof and in ejectingthe casting from the cavities or impressions of the die, and also illustrating the movement of the casting angularly to the dies or the direction of movement thereof.

Fig. 5 is a longitudinal detailed sectional view showing one scoop as applied to a stringer tape with the die omitted; and

Fig. 6 is a view similar to Fig. 2, showing the invention applied to a two cavity die.

In the formation of die castings, it has been customary to provide die cavities limited to such configurations as permit the dies to be drawn off the casting, while the latter is stationary, by movement of the dies away from each other in opposite directions in the same line (for consulting castings, or in other words, castings having recessed surfaces, with the greatest depth of the recess centrally of the casting and at the parting line of the dies, for example, in forming a casting of substantially V-cross sectional form, as hereinafter more fully described.

With castings of this type and kind, I have conceived a method forming the subject matter of a separate application of moving the, dies toward and from each other at an angle common to the angle of inclination of the diverging walls forming the recess or undercut portion of the resulting casting. The application in question constitutes application Serial Number 546,180, filed July 22, 1944, now Patent No. 2,426,408, for a patent on Method of forming undercut die castings.

With the present invention, however, I have conceived the possibility of forming undercut portions in castings of the kind under consideration and by movement of the dies toward and from each other in a common plane in accordance with the conventional and well known methods, I can utilize that portion of the die cavities forming the undercut in the resulting casting as the means to eject the casting from the die cavities, and also to feed the casting at right angles to the line of movement of the dies toward and from each other. By reason of this novel method, undercut castings can be formed, and the castings simply and easily ejected from the die cavities actually in a manner which is simpler and more positive than with the use of ejector pins, as commonly practised in the die casting art for ejecting conventional non-undercut castings from the die cavities.

The present invention also deals with the method of producing scoops for separable fastener stringers of what I term the coreless type, in other words, dispensing with the use of conventional core pins for forming sockets or female coupling portions in parts of the scoops. From this standpoint, the invention deals with scoops such as of the type and kind more fully and completely disclosed in my prior application Serial Number 531,618, filed April 18, 1944.

While the invention generally speaking deals with the formation of die castings, and particularly castings formed on mounting members, in order to illustrate one adaptation of the invention, Ihaveshown it appliedto the formation of die cast scoops, such for example, as the scoops H) on the edge of the stringer tapes II. The scoops in question are of the typ and kind which I term coreless scoops, where no core pins or the like are necessary to form the desired contour in the coupling end portions of the scoops. The scoops are of substantially V- cross sectional contour, or as seen in the drawing inverted V-cross sectional contour having the diverging coupling side portions I2 and I3, which side portions have lower diverging walls or surfaces l4 and corresponding upper surfaces I5, the latter being slightly contracted or tending to converge with the angularity of the walls [4. This cross sectional contour forms an undercut longitudinal channel or recess l6 on the lower surfaces of the scoops, and a corresponding longitudinal ridge I! at the upper surface thereof.

Considering Fig. of the drawing, it will also appear that the coupling end portion of the scoop has on upper and lower surfaces transverse recesses l8 and i9, outwardly of which are corresponding projecting members 20 and 2|, these latter recesses and projections forming between coupled scoops of opposed stringers the means for preventing lateral separation of the stringers, whereas the V or inverted V-cross sectional contour of the scoops will retain coupled scoops against transverse separation, as more specifically dealt with in the application hereinbefore identified.

In Fig. 5 of the drawing 22 represents the gate portion of the casting which is removed in' the completion of the formation of the stringers. This gate is, as in other constructions of this kind, arranged on the parting line 23 of two relatively

movable dies

24 and 25, the

dies

24 and 25 have on adjacent surfaces thereof an opening, and registering at the parting line 23, cavities or

impressions

26 and 21. The lower surfaces 28 of these cavities form the surfaces I4 of the resulting cast scoops, whereas the surfaces 29 form the upper surfaces l5 of the cast scoops, as will clearly appear from a consideration of Fig. l of the drawing.

The illustrations in Figs. 2, 3 and 4 of the

dies

24 and 25 are diagrammatic from the standpoint that the complete contour of the die cavities is not shown, as it would appear in the background, for the formation of the irregular contour defined by the recesses l8 and i9 and projections 20 and 2|. This is done to simplify the showing, as these views become much clearer in illustrating the more important phase of this conception which deals with the election of the castings from the

cavities

26 and 21. It is sufficient for present purposes to note, as clearly illustrated and described in the above identified copending application, that while the thickness of each scoop varies throughout its length, each crosssection, no matter where taken in the length of the scoop, is of V-shape. Hence the die cavity sections in planes other than but parallel to those illustrated in the accompanying drawings, differ therefrom only in the thickness of the side portions of the V. Accordingly, the below described operation in relation to the sections illustrated serves equally well for any other selected section.

After a casting has been formed, as illustrated for example in Fig. 1, the

dies

24 and 25 are then separated in the direction of the arrows 3B, which appear in Figs. 2, 3 and 4 of the drawing. These three figures show three stages of movement of the dies away from each other in a direction normal to the parting line of the dies to show how in these stages of operation the resulting casting is moved upwardly in the direction of the arrows 3| in said figures, or at right angles to the path of movement of the dies from each other.

In this operation, the surfaces 28 act as cams moving along the surfaces l4 of the casting, and thus force the casting upwardly until, as seen in Fig. 4, the casting is entirely out of the die cavities, at which time the casting may then be offset downwardly together with the tape il in the direction of the arrow 32, Fig. 4, to bring the next section of the tape II in position to receive the next successive casting, and then the above operation is repeated.

In the above ejection operation, it will appear that the upper surfaces l5 of the casting immediately become free of the surfaces 29. In other words, these surfaces do not interfere with or hinder the upward movement of the casting. This is facilitated by the fact that the surfaces 28 and 29 are diverging with respect to each other in the direction of the outer or abutting surfaces of the dies. In this connection, it will be understood that as long as the upper wall structure of the die cavity does not interfere with the upward movement imparted to the casting, or

in other words, as long as these upper surfaces are free of the casting, the described operation of ejection will take place.

In the method of automatically forming successive die castings on a mounting member, in addition to feeding the mounting member stepby-step in one direction with respect to the dies to bring the successive sections of the member in position to receive the dies, with my new method, the mounting member also has an intermittent feed, namely the feed which takes place for ejecting the casting. In the particular ap: plication illustrated it is preferred that this inter mittent ejecting feed be in a reverse direction to the said step-by-step feed, and the extent of this reverse feed will be equal to the depth of the undercut employed, thus the deeper the undercut the greater the feed. In an automatic die casting machine of the kind under consideration, means will be provided for feeding the tape into position for receiving the next successive casting, and this feed may also operate to feed the tape in the reverse direction consistent with the reverse feed of the casting in ejecting the casting from the dies.

In Fig. 6 of the drawing is shown a slight modification wherein two castings l0, identical with the castings Ill shown in Figs. 1 to 5 inclusive are simultaneously formed between relatively movable dies 33 and 34 which are generally similar to the

dies

24 and 25, excepting that each die 33 and 34 will have a pair of

cavities

35 and 36, thus forming the two castings l0 simultaneously on the tape ll, otherwise the method of procedure is identical with that shown in Figs. 2 to 4 inclusive, the showing in Fig. 6 being similar to that of Fig. 2. The only other difference in the two methods would be that with the construction shown in Fig. 6, the tape feed mecha nism would operate to feed the tape a greater distance in the direction of the arrow 32 in order to bring two new sections of the tape in position to receive the next successive pair of castings. From this standpoint, it will be understood that any desired number of castings may be simul taneously formed on the tape or mounting member, or in other words, formed in a single casting operation, and regardless of the number of castings formed, the back feed in the ejection of the castings from the die cavities will be no greater thanin ejecting a single casting, but the normal tape feed for spacing the tape or mounting memberwill be followed to suit the number of castings being formed.

In the more general uses of the invention, it will be apparent that any undercut casting may be formed between dies operated in the manner herein described and automatically discharged or ejected in the separation of the dies as long as the castings are of such contour as to otherwise free themselves from the die cavities and have no wall structures on surfaces thereof opposed to the undercut surfaces which would have the tendency to lock the castings in the dies, or in other words, lock the dies against separation.

From this standpoint, it is well to state that to the skilled mechanic consideration of the structure as shown in Fig. 1 of the drawing would appear toshow or illustrate a casting locked within the dies so that the dies could not possibly be separated. However, the illustrations in Figs. 2, 3 and 4 of the drawing clearly show that by allowing the castings to move or be fed relatively to the die movement, these castings will be automatically ejected from the die cavities. It will also be understood that it is immaterial in which direction the casting is fed in ejecting the same from the die. Here the illustration in the accompanying drawing is simply to be consistent with conventional practises in the formation of separable fastener stringers. It will be more definite to state that the castings are moved, in the ejection thereof, in the direction of the surface opposed to the undercut surface of the casting.

It is to be understood that the invention is not limited to an undercut in the casting where the greatest depth of the undercut is centrally of the casting or at the parting line of the dies. In some instances and by reason of other cross sectional contours of the undercut portion, the dies may be required to move a greater distance in separation, in order to clear the casting, than would be required by the length of the undercut portions at the sides of the castings, but in all instances, the castings are moved in the direction indicated to the degree corresponding to the depth of the undercut, or at least the deepest undercut in the casting. Here it will also be kept in mind that one side portion of the casting may have an undercut deeper than that of the other side portion thereof.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is:

l. The method of forming die cast scoops of separable fastener stringers having undercuts on one surface thereof, which comprises moving a pair of movable dies toward each other and a tape in a common plane, forming a cast scoop in undercut cavities on adjacent surfaces of said dies and on said tape with the dies in closed position, forming by said undercut cavities an undercut recess longitudinally of one surface of the scoop, and then separating said dies and coincidently ejecting the casting from the die cavities at right angles to the path of movement of the dies by moving that part of the wall structure of said cavities forming the undercut recess in said casting at an angle to the walls of said recess.

2. The method of forming die cast scoops of separable fastener stringers having undercuts on one surface thereof, which comprises moving a pair of movable dies toward each other and a tape in a common plane, forming a cast scoop in undercut cavities on adjacent surfaces of said dies and on said tape with the dies in closedposition, forming by said undercut cavities an undercut recess longitudinally and throughout the entire length ofone surface of the scoop, then separating said dies and coincidently ejecting the casting from the die cavities at right angles to the path of movement of the dies by moving that part of the wall structure of said cavities forming the undercut recess in said casting at an angle to the walls of said recess, and then feeding the tape to bring the next section thereof in position to receive the next successive cast scoop.

3. The method of forming successive die castings, which comprises forming a casting between diesmovable toward and from each other in a common plane, the dies having cavities shaped to form undercut camming surfaces therein and to produce undercut camming surfaces on the resulting casting, and ejecting the casting from the die cavities during the separation of the dies by moving the cam surfaces of the die cavities at an angle to the cam surfaces of the casting, thus camming the casting out of the dies in a different direction from the path of movement of the dies.

4. The method of forming successive die castings, which comprises forming a casting on a mounting member between dies movable toward and from each other in a common plane, the dies having cavities shaped to form undercut camming surfaces on the dies and to produce (:0- acting undercut camming surfaces on the resulting casting, ejecting the casting from the die cavities during the separation of the dies by moving the cam surfaces of the die cavities at an angle to the coacting cam surfaces of the castings and thus moving the casting relative to the dies by virtue of a cam action, and feeding said mounting member in a reverse direction to said movement of the casting to space successive castings on said member.

5. The method of forming successive groups of die castings, which comprises forming a group of die castings on a mounting member between dies movable toward and from each other in a common plane, the dies having groups of cavities, each casting in the group having undercut cam surfaces formed by corresponding surfaces in the die cavities, ejecting the group of castings from the die cavities during the separation of the dies by moving each die at an angle to the undercut cam surfaces of the group of castings so as to force the latter cam surfaces to coincidently use and ride over the cam surfaces of the die cavities and thus move the castings in the direction of the surfaces opposed to the undercut surfaces of the castings, and then feeding said member relatively to the dies to space successive groups of castings on said member.

6. The method of forming a casting by means of a pair of dies movable toward and from each other in a direction substantially normal to their mating surfaces, the mating surfaces of the dies having registering cavities partially defined by having a central longitudinal ridge therein, which comprises injecting casting material into the die cavities with the dies in closed position to form a casting having a longitudinal valley defined by said ridge, then separating the dies and moving the ridge portions of the dies over the valley surfaces of the casting to move the casting 7 ing for movement relatively to said dies when in separated position.

'7. In the formation of die cast scoops of separable fasteners by means of separable dies having mating cavities including surfaces extending at such angles with respect to the parting line of the dies as together to form an undercut recess on one face of the scoop cast in such cavities and a complementary ridge on the opposite face of the scoop, said undercut recess being defined by walls angularly disposed relative to the parting line of the dies, the method of forming a succession of spaced scoops on a stringer tape, which includes the steps of closing such dies on the tape, filling the cavities with casting material, withdrawing the dies from their parting line in a direction normal to such line and simultaneously therewith moving the cast scoop and the tape in a difierent direction by virtue of a camming action exerted by the angularly extending surfaces of the die cavities against the angularly disposed walls of the undercut recess of said scoop.

8. In the formation of die cast scoops of separable fasteners by means of separable dies having mating cavities including surfaces extending at such angles with respect to the parting line of the dies as together to form in such cavities a scoop having an undercut recess bounded by angular walls on one face of the scoop and a com plementary ridge on the opposite face of the of said scoop.

LOUIS H. MORIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 488,570 Miller Dec. 27, 1892 548,895 Staples Oct. 29, 1895 1,370,192 Crate Mar. 1, 1921 1,609,460 Buttles Dec. 7, 1926 2,218,091 Marinsky et al Oct. 15, 1940 2,263,037 Gits Nov. 18, 1941 5 2,322,908 Poux June 29, 1943 2,355,846 Brundage Aug. 15, 1944 2,365,764 Kastner Dec. 26, 1944 FOREIGN PATENTS 30 Number Country Date 625,209 Germany Feb. 6, 1936