US2802A - Improvement in the manner of forming molds for casting spoons - Google Patents

Description

iQiNirnD STATES PATENT Oil-inicia,

LUTHER BOARDMAN, OF EAST HADDAM, CONECTIGUT.

IMPROVEMENT IN THE MANNER OF FORMING MOLDS FOR CASTING SPOONS, &c,.

Specilication forming part of Letters Patent No. 2,8() 2, dated October 7, 184i.

To @ZZ 1071/0171/ it may concern-f Beit known that I, LUTHER Bon-entran, of Fast Haddam, in the county of Middlesex and State of Connecticut, have invented a new and useful Manner of Forming Metallic Molds for the .Casting of Spoons and other Articles; and

the manner in which I form the gate or channel by which the metal is to enter the mold. In casting spoons I usually cast two in the same mold, as this is more economical than casting them singly, although the latter may be done upon the same principle as that which I adopt in forming them in pairs.

A B represent the cavities formed in the molds for the reception of the metal. C C is agate or channel through which the metal is to enter, and which is continued down to the point I), where it divides into two channels, one leading to each spoon in a descending oblique direction, as reprented at E and Fin the drawing. Toward the upper end of the main gate there are two other gates or sprues leading from the main gate C C, and connecting it with the upper portion ofthe cavity for the articles to be cast. These gates or sprues are made to incline upward, as shown at G H. From the upper end of each spoon or other article there is usually a small air-channel leading upward, as shown at I J. This completes the formation of the mold.

The improvement in this mold consists. in the particular manner in which the main gate C C and the lateral gates or sprues E F and G H are arranged and combined with each other and with the cavities in which the spoons or other articles are to be formed, said form and arrangement of the gates being especially' adapted to the casting of spoons and similar articles in metallic molds. In the ordinary manner of casting spoons in such molds the metal is poured in by a gate leading directly into the upper portion of the cavity, and the result is that the scoria, which is always forming in the metal, accumulates in the upper end or handle, and renders the article more or less porous in that parta defect which is rendered evident in the process of iinishing the article with a buit". By my arrangement the metal enters at a certain distance above the lower end of the article to be cast, as at E F, where it corresponds with the broadest part oi' the bowl of a spoon, audit continues to rise in the cavity or cavities until it arrives at a level with` the upper lateral gates, as at G H, when it iiows in through those channels. and when thus introduced the upper end of the article will be found to be perfectly free from all visible porosity.

I am fully aware that articles have frequently been cast in sand by causing the gate to de scend to the lower part of the cavity made in the flask by the pattern, and allowing the metal to low regularly upward, this having been done to prevent injury to the face of the mold in the casting of iine work bythe descent of the molten metal in a continued current along it; but in metal molds the object to be attained and the means of attaining it are dif-v ferent from those just described in casting in sand. Metallic molds, which are good conductors of heat, require to be kept at a given temperature to admit oi' the setting and removal of the cast article without waste of time, While it is important that this setting shall not be so sudden as to cause it to take place before the article is perfectly formed. Now, in an -article of the length of a spoon it will be found that if the metal is allowed to descend along a gate to its lower end and then to ascend to the upper end by the pressure of that contained in the gate the spoon cannot be cast without keeping the mold at a temperature which would defeat the object; but by means of the two lateral gates or sprues to each spoon, arranged in the manner or substantially in the manner herein described and represented, the desired end will be attained.

Having thus fully described the manner in which I construct my metallic molds for casting spoons and other articles of a similar char: acter, what I'claim therein as new, and desire to secure by Letters Patent, is-

The forming of such molds with a main descending gateleading down nearly to the lower spoken of a single lateral ascending gate or end of the spoon or other article to be east, sprue leading to each cavity, there may be Where it is to communicate with the proper two or more such'lateral ascending gates with cavity by means of a lateral descending gate out producing any injury, although I do not or sprue, in combination with the sprue above think them necessary or desiiable.

this and toward the upper end 'of the cavity for receiving the metal, having an ascending` LUlHER BOARDMAB' direction, the Whole being formed in the man NVitnesses:

ner and for the purpose herein fully set forth; THOs. I). JONES,

and I Will here remark that, although I have EDWIN L. BRUNDAGE.

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