US2349498A - Casting shot - Google Patents

Description

y 1944, .J. E. HATFIELD 2,349,498

CASTING SHOT Filed Sept. 22, 1942 3 Sheets-Sheet 1 INVENTOR.

2? F76. 2 BY firmer/Era May 23, 1944. J. 1:. HATFIELD 2,349,498

CASTING SHOT Filed Sept. 22, 1942 3 Sheets-Sheet 2 v FIG. 3 JkMEsE flaw-751.0

34 INVENTOR.

M Flam (M 56 4 Tree/vs rs May 23, 1944. J. E. HATFIELD 2,349,498

CASTING SHOT Filed Sept. 22, 1942 3 Sheets-Sheet 3 INVENTOR.

fines E. Horns/.0

Patented May 23, 1944 CASTING SHOT James E. Hatfield,

ShakenHeights, Ohio, assignor to Grant Storage. Battery Company. Minneapolis, Mi'nn., a corporation of Minnesota Application SeptembenZZ, 1942, Serial No. 459,240

1 Claim. This invention relates to the making of shot,

and has for its principal object to provide a method and apparatus by which lead shot may be cast very economically, rapidly, and accurately.

An important feature of the present invention is the manner in which the shot are cast. According to the present invention, a quantity ofshot is cast in a mold in a sheet or multiple sheet with the shot cavities extending horizontally and vertically. Perfect shot are formed by reason of the manner in which the mold cavities are Vented. The cavities are arranged in horizontal rows which are filled from the bottom to the top, it being a feature of the invention that the cavities are connected not only horizontally but also vertically by small passages or channels so that each shot cavity is well vented with the result that the lead shot which is cast therein is perfectly formed, and when the casting is completed each shot is connected to the adjacent shot by narrow connecting portions.

Not only is each mold cavity vented vertically as well as horizontally, which facilitates the casting of the shot in a sheet or group, but in view of the facility with which the metal flows into and upwardly from each cavity, the temperature of the molten metal can be less than would otherwise be the case. After the casting has been made, water is sprayed on the casting to more quickly congeal the by means of a gang punch, each shot is severed from the adjoining shot, leaving four burrs Where the connecting portions were located.

Next the shot are subjected to infra-red rays or other means for rapid drying to prevent the formation of an oxide on the metal and are thenplaced in a tumbling barrel-where the burrs are pressed into the shot in the tumbling operation.

The invention may be further summarized as consisting. in certain novel details of construction and in certain details of the method described in the specification and set forth in-"the appended: claim.

Referring now to the drawings,

Fig. 1 is. a perspective view of a two-part mold in which the casting is made;

Fig. 2 is a face View of one of the mold memberson a larger scale than shown in Fig. 1, looking-the direction of the line 22 of Fig; 1;

Fig. 3 shows a view of the casting which" is produced in the mold;

Fig. 4. is a. sectional-view through a gang punch metal, and then,

by which the shot are severed from the castin Fig. 5 is a view taken along the line 5-5 of Fig. 4, showing a-face view of the male gang punch;

Fig. 6 is a view taken along the line 66 of Fig. 4, showing the female gang punch;

Fig. 7 is an enlarged sectional view showing the action of the male and female punching members; i

Fig. 8 is a view of one of the shot with the burrs thereon following the punching operation; and

Fig. 9 is a view of one of the shot after the tumbling operation.

Referring now to the drawings, Fig. 1 represents the two complemental members l0 and II of the mold in which the shot casting is made. Inasmuch as the illustrated casting is to be made in the form of a twin sheet, the mold is provided with three pouring gates l2, l3 and I4. One of the mold members has a series of ejecting pins l5 projecting from the rear side thereof. At the top of the mold, between the gates l2 and I3, and between the gates I3 and [4 there are provided, respectively, narrow vent passageways I6 and I1.

By reference to Fig. 2 it will be noted that extending from each gate l2, I3 and I4 are, respectively, vertical passageways l8, l9 and 20, the middle passageway l9- being preferably somewhat wider than the two end passageways l8 and 20. Additionally, the mold is provided with a lower horizontal passageway 2| and an upper horizontal passageway 22 joining the three vertical passageways."

Extending from the passageway l8 to the passageway l9 and from the passageway l9 to the passageway 20 are series of superposed equally spaced horizontal rows of shot cavities 23, the cavities of each horizontal row being connected= by horizontal channels 24. Similarly, the cavities of each horizontal row are connected by vertical channels 25 to the cavities above and below. The cavities of the lowermost row are connected to the lower passageway 2| by vertical channels 26 while the cavities of the uppermost horizontal row are connected by channels 2.! to the upper passageway 22. In a similar fashion the vertical rows of cavities next to the vertical passageways I8, l9, and 20 are connected to these passageways by: channels 28. It will be understood, of course, that the above described cavities, passageways, and channels are formed" in the adjacent faces of both mold members and H so that when the, mold members are closed the cavities, passageways, and channels of one mold member are in registering complemental relation with those of the other mold member to form the completed mold.

It will be seen that with a mold formed as described, when the molten lead is poured into the pouring gates l2, l3, and it, it will flow down the vertical passageways l8, l9, and 20, and it will fill successively the horizontal rows of cavities from the bottommost to the topmost. This progressive filling of the cavities from the bota1 into the cavities, particularly the middle cavtom to the top of the mold facilitates the escape of air from the cavities and enables the cavities to be filled completely and rapidly withmetal. It might be here stated that to facilitate the locating of the casting produced by -the mold in the gang punch press, one of the mold members is provided with a pair of pins 29 which extend across the uppermost channel 22 so as to form openings in the casting.

In Fig. 3 I have shown. a casting which is produced in' accordance with the present invention. It will be noted that this casting includes three sprues 30, a framework consisting of three vertical lead bars 3|, 32, and33, a lower lead bar 34 joiningvthe vertical bars and an upper horizontal bar 35 which likewise joins the three vertical bars 31, 32, and 33, two flashes 36 and 31 where the vent passages i6 and Il occur between the gates and two groups of framed lead shot 38, one located in the frame formed by the lead bars 3|, 32, 34, and 35 andthe other located in the frame formed by the bars 32, 33, 34 and 35.

It will be seen that the shot are spaced equal distances from one another, throughout each framed mass and that they are connected both horizontally and vertically by connecting portions 39. The mold cavities are completely filled and the shot are of practically uniform size throughout due to the venting feature by which each shot cavity of each horizontal row is vented vertically to the shot cavity above and also connected to the shot cavity below. This would not be possible if the horizontal rows were independent of each other and the shot cavities thereof were not all connected to the cavities above and below, but some of the cavities, particularly those at or adjacent the center of the horizontal rows would be imperfectly filled.

It will be noted by reference to Figs. 2 and3 that the molten lead passes down the vertical passageways and gradually rises'in these passageways as the molten lead flows horizontally into the shot cavities which are fed not only from the vertical passageways but by way of thevertical channels 25 into the shot cavities of the horizontal row above. Thus the moldis filled from the bottom up, eventually forming the upper bar 35 of the framework and theflashes 36and 31. When the operator sees the metal rise in the openings l3 and H, he knows that he has poured enough molten lead into the gates.

It'might be stated in passing that the vertical bars l8, I9 and add strength to the casting so asto facilitate the handling of the casting after it has been ejected from the mold.

As was previously stated, the facility with which the shot are cast permits a lower tem-.

perature of the molten metal than would be the case if a longer time was required for ing operation. Thus there isa saving in the gas l8, l9 and 2K to the bottom thereof the castities of each horizontal row, and even then, due to the lack of provision for venting the cavities independently of the inlets and outlets at opposite ends of the horizontal rows, the middle cavities might not be completely filled.

When the mold is opened and the casting is removed therefrom, the casting will be found to contain two openings 40 Where the pins 29 occur.

, As soon as the casting is removed from the mold, water is sprayed on it so as to quickly congeal the metal and then the casting is placed in a gang punchhaving a series of punches 4i spaced in accordance with the spacing of the shot 38 in each double framework or grille, which punches are carried by a holder 42 which is actuated in any suitable manner and which is slidable in a frame 53. Cooperating with the gang punches M and equal in number and spacing thereto are a series of openings M located in a stationary die'plate supported by a member 43 of the gang punch. The lead casting is accu-' rately located in the gang punch by the holes 49 which are cast therein, which holes receive a pair of pins' ltla, Fig. 6, of the lower plate 45 of the gang punch.

With this arrangement by one downward stroke of the holder 42 all the lead shot are punched out of the double framework in the manner best shown in Fig. 7. As shown in Fig. 4, they drop down into a cavity having a sloping bottom 41 with an outlet opening 38. The framework, including the sprues 3B and flashes 3B and 31, is returned to the melting pot. This procedure frees the shot 38 from the double framework,

except that there are four small burrs 49 on each shot where the shot was severed from the connecting portions 39. In practice, the sloping bottom 41 is a wire screen through which the lead connections fall but which will not pass the shot. After the gang punch has operated and the male member has returned to its highest position, an .air blast is used to remove the lead connections from the top of the female die member. Some of these, during the action of the air blast, may fall through the female openings in the die and then pass through the screen into a suitable receptacle.

Inasmuch as the shot are formed from pure lead which very-readily oxidizes, it is desirable that oxidation be prevented, particularly for certain uses of the shot.- Accordingly, a quick drying of the shot is desirable, and immediately after pletely driven into the shot, thus leaving a perfectly smooth exterior surface thereon as shown at 50 in Fig. 9. While the shot are of practically uniform diameter, they can, if necessary be screened or sorted by first passing them over a screen through which the undersized shot will pass, and then over a screen through which the shot of the required diameter will pass.

Thus it will be seen that there are numerous advantages which flow from the use of shot cavities vented horizontally and vertically.

While I have shown the preferred construction and have described the preferred steps of the method, I do not desire to be confined to the precise details shown, but aim in my claim to cover all modifications which do not involve a departure from the spirit and scope of my invention.

Having thus described my invention, I claim:

A mold for making shot having pouring gates at the top and a series of upright feeding channels leading to the bottom of the mold with air venting means between the pouring gates, and a series of shot cavities arranged in horizontal rows between the upright feeding channels, each row of cavities being directly connected with the upright feeding channels and each cavity being directly connected to the cavities above and below it, whereby the molten metal, on being poured into the gates, gradually fills the upright feeding channels and successively flows into the horizontal rows of cavities, each cavity being vented upwardly.

JAMES E. HATFIELD.

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