US57644A - Improved machine for making cast-steel castings - Google Patents

Description

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JOHN BLAKE TARR, OF CHICAGO, ILLINOIS, ASSICNOR TO HIMSELF AND I. E. MERRIHFWI, OF SAME PLACE.

IMPROVED MACHINE FOR lVlAKlNG CAST=STEEL CASTINGS.

Specication forming part of Letters Patent No. 57,644, dated August 28, 1866.

To all whom it may concern:

Be it known that I, JOHN BLAKE TARE, ot Chicago, in the county of Cook and State of Illinois, have invented a new and useful Machine for Making Castings of Cast-Steel; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, making a part of this specilcatiou, in whiche- `Figure l is a plan view of the machine adapted for casting car-wheels. Fig. 2 is an elevation of the machine. Fig. 3 is a vertical section through the machine, showing the three parts of the mold in positions for allowing the cast wheel to be removed from the machine. Fig. 4 is a vertical section, showing the three parts of the machine in position for receiving the metal.

Similar letters of reference indicate corresponding parts in the several iigures.

The object of this invention is to produce articles otcast-steel by casting this metal in molds and subjecting it to considerable pressure while in a melted state, for the purpose of expelling the air and rendering the metal more dense than it would otherwise be, and i'ree from blisters or other imperfections, as will be hereinafter described.

The machine which I shall describe isconstructed and adapted for producing railroadcar wheels of caststeel, but it is not contemplated to coune the invention to the casting of wheels, or parts of wheels, as other articles or objects can be produced by changing the form of the molds and without altering the principle of the invention.

To enable others skilled in the art to understand my invention, I will describe its con struction and operation.

In the accompanying drawings, A represent-s the base-plate otl the machine, which forms the lower section ofthe mold within which the wheel A is cast.

B represents a ring, which produces the circumference or tread ot' the wheel and a portion ot' the tlange thereof'. This ring forms the Vertical section ot' the mold, and it is fitted within a recess which is formed in the upper face of the horizontal section or'bed-plate A, as shown in Figs. 3 and 4.

C represents the upper section of the mold,

which produces the contour of the outer sul1A face ot the wheel, and forms, in conjunction with the ring B and base-plate A, a chamber or mold within which the -wheel is cast. Y

The hole which is through the center et the wheel A is `produced by means ot' a conical core, D, which isdriven through the central holes, which are made through the two plates A- and C, the largest end of said core being down, as shown in, Figs. 2, 3, and 4.

The horizontal section C ot' the mold is cast with three or more elevations, a a a, projecting perpendicularly from its upper surface, which portions have t'emale screwthreads formed in them for receiving the vertical screw-rods b b,

vwhich rods have spur-wheels c c c keyed on their upper ends, as shown in the drawings.

Circular enlargements or shoulders b b b are formed on the rods b near their upper ends, so as to press against a horizontal cross-head, E, and resist any upward movement or" said screw-rods.

The stair-wheels c c c have hubs or collars c c c formed on them, which afford a bearing upon the cross-head E tor each screw-shaft.

There is a central shaft, F, which has its bearing in the cross-head E, and which the driving-shaft for turning` the screw-rods I). The spur-wheel D on this shaft F engages with thethree spur-wheels c c c, and thus the said screws are all rotated simultaneously when it is desired to move the mold-section C up or down.

I The cross-head or head-piece is supported and held down bymeans of three upright posts, Gr C G, which are lirmly secured to the bedplate A and said cross-head F, as shown in the drawings.

Two or more hooked screws, g g, which are tapped into the hase-plate A at suitable points, are used for holding down the ring-section B, and similar hooks, h h, are tapped into the riug'section B, for the purpose of allowing this ring B to be lifted up by means of the section C, as shown in Fig. 3. This section B is thus elevated t'or the purpose of allowing of the removal of the wheel A.

Three or more in gates, ce c, are made through the upper section, C, and at the upper and smallest ends of these ingates daring holes are y made through dovetail slides fff, which lating said block and keeping' its exposed surfaceA always flush with the surface of the mold-see tion A, as shown in Fig. Any other refractv or\ substance may be used insteadof the plumbago which will. answer as well to prevent the liquid steel from melting the surface of the section A and adhering to it at the points below the iu gates.

Before commencing the operation of casting it is desirable to cover the entire surfaces of the sections of the molds inside with soot. 't0 prevent thel metal from burning and adhering to the mold.

The sections ofthe mold are adjusted in their proper positions, as shown inFigs. 2 and 4, and the centra-l core, D, inserted from beneath the base-plate A, through this plate and the upper plate, G. The liquid steel is then poured into the mold through the three ingates, and when the mold is full the slidesfffare immediately moved over theingates, so as to cut off the upper ends of the sprues s s and to close the openings. The main shaft. F is now rotated so as to turn all the screw-rods b b I) and depress the plate C with a steady and powerful pressure upon the liquid metal in the mold. This pressing operation will expel the air andV gaseous carbon from the steel through suitable apertures, which are made in the mold-sections for the purpose, and at the same time compress the steel so as to render it more dense. After the pressure has been removed, which is done after the casting has set, the plate C is elevated a suiiicient distance to free it from the wheel. rlhis plate G is then depressed again and the hooks h h turned over it, the

hooks g g being now turned outward, so asV to release the rin g-section B. This done,the shaft F is again rotated, so as to elevate the plate C, and with it the ring B, as shown in Fie'. 3, thus allowing` `the core D to be driven down and the cast-steel car-wheel to be removed from the mold-section A.

Itwill be seen that the upper section, C, of the mold vin which the casting is madeforms the follower of a press for condensing the steel and expelling' gas and\air from it while it is in a liquid or Vsemi-liquid state. Wheels or other articles thus produced will possess great strength. 'lfhey will be tough, and. not so liable to'crack under heavy blows or concussions as cast-steel commonly used.

Having thus described my invention, what I claim as new,and desire to secure byLetters Patent, is-

l.v Subjecting the cast steel, while in a liquid state and within the mold which is to give it the desired form, to such a degree of pressure as will cause the expulsion of air and gas from it and render it more solid, by means substantially as described.

2. Constructing the bottom of the mold, at those points only which are directly under the iugates, of adjustable blocks of plumbago or other analogous refractory substance, substantia-ily in the manner and for the purpose described.

3. The manner, substantially as herein described, of constructing the ingates with cutters on them, when said ingates are applied and g L, 0r their equivalents, substantially as described.

JOHN BLAKE TARE.

Witnesses vR. T. CAMPBELL, EDW. SCHAFER.

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