US1161101A - Apparatus for preventing blow-holes in castings. - Google Patents

Description

P. WINEMAN.

APPARATUS FOR PREVENTING BLOW HOLES IN CASTINGS.

APPLICATION FILED FEB. 24, 1914.

1,161,101. Patented Nov. 23, 1915.

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imprint, and from the sides UNITED STATES PATENT UT TTCE.

PARKER WINEMAN, OF CHICAGO, ILLINOIS.

APPARATUS FOR PREVENTING- IBLOW-HOLES IN CASTINGS.

Specification of Letters Patent.

Patented Nov. 23, 1915.

Application filed February 24, 1914. V Serial No. 820,723.

To all whom it may concern Be it known that I,'PARKER WINEMAN, a citizen of the United States, and residing at Chicago, Cook county, Illinois, have invented certain new and useful Apparatus for Preventing BloW-Holes in Castings, of which the following, taken in connection with the drawing, is a description.

My invention has forits object the production of apparatus to be used in connection with a flask of usual construction, into which sand is rammed upon a contained pattern to form a mold, in which and during the operation of pouring the hot metal, the air and gases are drawn therefrom, so that the finished product is free from honeycombs or blow-holes, which is a very common defect as castings are made at the present time, and a cause of much annoyance and expense in their production.

Heret'ofore it has been customary to puncture the sand with a steel wire of suflicient size extending from the top to the mold or to the imprint, to vent for the escape of air or gas accumulated therein, also other openings or risers are made extending through the sand to the imprint through which a portion of the hot air and gases escape to atmosphere as the mold is filled with hot metal. This method, however, has not been suflicient to prevent the honey-combing of the metal in the castings, especially in steel castings, and very frequently in gray-iron castings, as Well as other metals.

The principal cause of the defects referred to arises from the gas generated while the molten metal is being poured into the imprint, as it'reaches the damp sand. The method above referred to and heretofore employed for venting, is inadequate for the escape of gas and hot air, and in the process the metal is retarded in its inflow into all parts of the imprint in consequence of which the gas, hot air, and atmospheric pressure,

amounting to approximately 14 pounds per quarter inch, all of which retards the inflow of the metal to all parts of the imprint, and thus the gas, hot air and atmospheric pres sure acting against the flow of the metal prevents a free and sufficient escape of the gas and tends to force it into remote pockets, angles, corners, etc., where it is trapped and more or less of it retained in the metal while it is cooling, thus forming the blow-holes and honey-combs which are decided defects in all poured into the mold in which case the air I and gas remain with no vent through which i to escape.

By the use of my construction, in combination with a well known process of creating a vacuum, the gas and hot air together with the pressure of the atmosphere being removed, the time spent in probing to vent will be saved. the inflow of the metal will be increased and the defects will be reduced to a minimum, and by removing the cause of the defects the result is a perfect product. To accomplish this result I provide a mold wherein I create a vacuum (or as near a vacuum as is possible) and withdraw all the gas and hot air relieving the mold or imprint of air pressure by eliminating the gaseous products as fast as they are generated while the molten metal is being poured into the imprint, this is done with the exhaust fan and my construction. 7

In the accompanying drawings I have illustrated what .I now consider the preferred form of a construction adapted to carry out my invention and accomplish the results above set forth, and in these draw- 1ngs- Figure 1 is a top plan View of a flask or mold, with one-half the cover broken away; and Fig. 2 is a longitudinal sectional View taken on line 2, 2 of Fig. 1.

In reducing my invention to practice I employ a mold or a flask of two parts A, A of the kind now in ordinary use having mold boards in the bottom thereof. In this flask is placed the sand to form the desired mold.

In the drawing I have illustrated a wheel through which the air or gas is drawn from the mold and out through the exhaust as hereinafter described. These ports reach in depth approximately to the bottom line of the pattern B and open into the groove a at the top of the sand as shown.

WVhen the top of the flaskis in position ports 61 ,0 extend to the grooves 01' recesses a, These ports a may be made by a pattern or by probing. C,'C, are exhaust cups inverted on top of the sand in the flask and pressed downwardly into the sand a sufficient distance to form an airtight chamber into which the ports a exhaust, or into which the gas or air is drawn.

Extending from said cups to the pattern B are the ports D, D.

Extending from the cups C, C, to the vent pipe D are pipes c, 0, which are preferably flexible. The vent pipe D is a short pipe,

. ment of the employees.

and connected through and with the pipe D which may be made in sections and adaptedto be fitted to the pipe I) in any desired manner. The pipe D has connection with a suction fan D located at any convenient placeabout the building. This suction fan is of any well known type of construction and details thereof will not be here given. This fan is used to create a vacuum- (or partial vacuum) and is driven by a belt or motor in the ordinary manner. In the use of a device of this kind I prefer to have a main overhead pipe provlded with an exhaust fan at one end thereof which will be sufiiciently powerful to serve a large number of molders, each flask being provided with a vent pipe extending to the main over-head pipe D From the overhead pipe D any number of flexible pipes may be connected and extended to the flask. l/Vith the use of this construction, when the molten metal is poured into the mold, the hot air andgas arising therefrom are drawn through the different ports a, a, and D, to the exhaust cups C, C, thereby at once relieving atmospheric pressure.

One of the advantages in the use of this invention, in addition to the advantages already pointed out, is that all air and gas arising from the molten metal passes through the pipes and is vented to atmosphere outside the building, so that none can escape in the shop or foundry to the detri- In thedrawings I have illustrated only the principal objects of my invention, which as will be obvious, may be carried out in different ways, and I wish tobe understood as contemplating different arrangements of the ports to exhaust from different parts of the mold, also that-more exhaust cups and diiferent shapes suitable for the casting may be used if found desirable, also that the pipe connections may be changed.

In the use of this construction the cups U, G, are simply pressed into the sand which forms an air-tight chamber, the cups being held in position by atmospheric pressure.

I claim:

1. In an apparatus of the class described,

a molding flask containing prepared sand having ports provided therein at predetermined intervals, and means for drawing through said ports while the same is being filled, all the gases generated by the hot molten metal arising on the inner surface of the mold.

2. In an apparatus of the class described, a molding flask containing prepared sand having ports provided therein at predetermined intervals, inverted receptacles of any form communicating with said ports, and a means for withdrawing through said ports gases arising from the hot moltenmetal on the surface of the mold. while the same is being filled with molten metal.

3. In an apparatus of the class described, a molding flask containing prepared sand having ports leading to the mold provided therein at predeterminedintervals, inverted receptacles registering with said ports, vent pipes connecting with said receptacles, and means operating through saidpipes to withdraw the gas generating from the damp prepared sand comprising the mold as the hot molten metal is rising in the mold.

4. In an apparatus of the class described,

the combination of a plurality of flasks con- PARKER WINEMAN.

Witnesses 2 WILLIS Kine, CHARLES I. COBB.

' taining prepared sand and having'ports ex-

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