US2128129A - Stereotype metal furnace - Google Patents

Description

Aug 23, 1938.

M'. FARLEY STEREOTYPE METALv FURNACE Filed Sept. 25. 1955 2 Sheets-Sheet 1 M. M. FARLEY STEREOTYPE METAL FURNACE Filed Sept. 25, 1935 Aug. 23, 1938.

2 Sheets-Sheet 2 Patented Aug. 23, 1938 PATENT. ,o-F w-E STEREOTYPE METAL FURNACE Marcus M. Farley, Battle Creek, Mich., assignor to Duplex Printing Press Company, Battle Creek, Mich., a corporation of Michigan Application September 25, 1935, Serial No. 42,124

1 Claim.

This invention is an improvement in stereotype metal casting apparatus, and its object is to conserve and utilize the waste heat of metal melting furnaces (especially those used for melting stereotype metal in making printing plates), to keep the metal discharge spout as near as possible to the temperature of the metal in the melting pot as the metal passes through the spout to the casting box. The melting temperature of stereotype metal is low and in its passage from the pump through the discharge spout it ordinarily loses .considerable heat, and consequently the temperature of the metal at the discharge point may sometimes be too low to produce plates of good printing qualities; or the temperature of the metal in the pot must be kept higher than necessary, to allow for the drop in temperature of the molten metal while passing through the spout; but at such high temperatures some components of stereotype metal will volatilize and reduce the quality of the metal necessary for making perfect plates. If the metal is kept at the proper casting temperature in the melting pot, there is a possibility of some of the metal freezing or adhering to the spout, which affects the accuracy of the casting.

Heretofore attempts have been made to overcome the above mentioned objections by heating the exposed part of the spout by auxiliary gas burners, or electric heating elements, which are expensive and troublesome. My invention eliminates the need of any extra heating apparatus and insures maintenance of the proper temperature of the metal delivered to the casting box.

The accompanying drawings illustrate two embodiments of the invention as applied to two types of metal melting pots and pumps. I will explain the'invention as disclosed in said drawings, and summarize in the claims the essentials of the invention and novel features of construction and combinations of parts for which protection is desired.

In said drawings:--

Fig. 1 is a plan view of a metal melting pot and pump equipped with an embodiment of my invention.

Fig. 2 is a side elevation partly in section of Fig. 1.

Fig. 3 is a plan View of another form of melting pot and pump equipped with an embodiment of my invention.

Fig. 4 is a side elevation of Fig. 3.

Figs. 1 and 2 illustrate an ordinary melting pot and furnace for melting stereotype metal. The furnace I may be of any suitable construction,

and has within it an ordinary melting pot 2. Access can be had through a door lb to the combustion chamber in the furnace below the melting pot.

Within the pot 2 is arranged a melting pump 4 of any suitable construction having a discharge spout 4a through which the metal can be conducted to a casting box In of any suitable type. The pump 4 may be operated in the usual manner by a hand lever 40 as indicated in the drawings. The spout is fastened to the outlet of the pump and extends upwardly and outwardly to a point exterior to the pot so that the metal, when the pump is operated, can flow through the spout and be discharged therefrom by gravity into a stereotype plate casting box 10 standing beside the pot; the metal filling the box by gravity or hydrostatic pressure.

The molten metal is pumped through spout 4a to the casting box l0, and to prevent injurious drop in temperature of the metal passing through the spout from the pump to the mold I utilize hot waste gases to heat the spout. The pot has a hood 6 to catch the hot products of combustion and direct them to the outlet. The spout 4a extends through an opening in the hood as shown.

In the type of furnace shown in Figs. 1 and 2, the melting pot shown in Fig. 1 is heated from below by the use of coal, coke, oil, or gas, and the products of combustion escape through an outlet I a in the hood into a pipe which conducts the gases to any desired point of discharge.

In utilizing my invention, the furnace outlet la is connected by a pipe 3 with a pipe or jacket 5 surrounding the spout 4a for the greater portion of its length. The inner end of said jacket is connected with the opening in the hood through which the spout projects, and the outer end of the jacket has an opening connected with a discharge pipe 5a. The heated products of combustion pass from the furnace into the jacket 5 and heat the spout 4a. After passing into and through jacket 5 the products of combustion may pass through pipe 5a. to any suitable point of discharge.

It is common practice to install a hood over the melting pot, connected directly with a flue, to protect the operator and carry off the fumes and heat from the melted metal. To utilize the heat of the molten metal the upper end of the furnace and open end of pot 2 may be covered by a metal hood 6 and the inner end of the jacket 5 connected to said hood so that not only the products of combustion but also the heated gases and maintains the spout at the desired high tem-' perature.

I claim Apparatus of the character specified comprising a metal melting furnace having an outlet for waste gases of combustion; a metal pot on said furnace, a hood over the pot, a metal pump in the pot, a spout connected with the pump and extending from the pump to a point outside the hood, a jacket connected with the hood and surrounding the exposed portion of the spout, a pipe for directing hot waste gases from the outlet of the furnace into said jacket, and a discharge 0 for the hot gases at the outer end of said jacket.

MARCUS M. FARLEY.

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