US222922A - Improvement in casting car-wheels - Google Patents

Description

2 Sheets--Sheet 1.

G. G. LOBDELL. Casting Car-Wheels.

No. 222,922. Patented Dec. 23, 1879,.

2 SheetfSheet 2. G. Gr. L'OBDBLL. Casting Cai-Wheels.

No. 222,922. Patented Dec. 23,1879.

NITED STATESPATENT OFFICE.

GEORGE G. LOBDELL, OF WILMINGTON, DELAWARE.

IMPROVEMENT IN CASTING CAR-WH-EELS.

Specification forming part of Letters Patent No. 222,922, dated December 23, 1879; application filed November 3, 1879.

`mold through outlets concentric with, but at a short distance from, the chill, so that the metal shall not be brought into violent contact with the same; and, second, that, while the gyration of the metal in the mold tendsto produce a good chilled surface, this tendency is enhanced by causing the metal to move in contact with a heated chill.

In order that my invention may be thoroughly understood and distinguished from prior inventions connected with the art to which my improvements relate, it ,will be well in the outset to refer to the patent of J. Harley, March 3, 1835, for casting hollow chilled rolls, and to the views, Figures l and 2, in`

Sheet 1 of the accompanying drawings, which are reproductions of views in the drawings attached to the said patent.

In this invention the molten metal is first introduced from above into a central reservoir below the mold, and is directed from the latter through inclined gates or passages upward into the mold. -It will be seen that the metal,

as it issues from these gates into the mold, must necessarily strike against the chill. If, instead of causing the molten metal to enter the mold abruptly from the inclined gates, the latter had terminated in upwardly-inclined passages arranged concentrically with the chill, as shown in Fig. 3, there would have been the desired gyration of the metal inthe mold, Without that Violent contact with the chill which tends to produce an imperfect chilled surface.

The view Fig. 3 serves partly to illustrate one of the main features of my invention.

Fig. 4, Sheet 1, shows a vertical section of a mold prepared for casting car-wheels according to my invention; Fig. 5, a plan view, showing the gates and, their relation to the rim of the wheel, the latter being shown in dotted lines; Fig. 6, a vertical section on the line l 2, Fig. 4; Fig. 7, Sheet 2, a perspective view of a sand-core used in the mold; and Figs. 8 and 9, sectional views, illustrating the mode of preparing the lower portion of the mold.

In Fig. 4, A is the central pouring-gate ot' the mold, this gate being in the core B, which forms the opening in the hub of the wheel. The central gate communicates with a series of gates, E-six in the presentinstance-which are preferably arranged radially, as shown in Fig. 5. The direction of' each gate E is changed abruptly at fr, immediately below and at a short distance from the rim portion G of the mold, the portion y of the gate between the point x and its outlet at the said rim tak ing the upwardly-inclined course shown in Fig. 6, and, as shown in Fig. 5, a course concentric with the rim of the wheel, the outlet being narrower than the rim, as will be seen by comparing the said outlet in Fig. 5 with the dotted lines which represent the thickness of the said rim.'

H is the chill which defines the tread ofthe wheel, and which will be referred to hereinafter.

The molten metal poured into the central gate, A, will flow simultaneously through the six radial gates, and will in each gate take an abrupt turn at x, thence an up wardly-inclined course, and will iinally issue into the rim portion ofthe mold in a stream, the direction ot' which will, like the outlet, be concentric with but at a short distance from the chill. The desired gyration of the molten metal in the rim portion of the mold will thus be brought about without any impact or splashing of the stream against the face of the chill.

Heretofore it has been the practice in casting chilled objects, with the View of insuring the rotation ofthe molten metal in the mold1 to direct the streams of metal :in an upwardtive in Fig. t.

inclined course through gates, as in the aforesaid patent ot' J. Harley, March 8, 1835, and the same plan has been more recently pursued in casting chilled car-wheels; but the direction of the streams ot' metal issuing into the molds has always been such as to strike against the chill, and to this may be attributed the scabby imperfections which arevbeneath the skin ot' the treads of chilled wheels, and which are exposed when, by repeated use, the skin concealing these imperfections is broken.

My main objecthas been to cause the molten metal to issue into the mold in streams concentric with but at a distance from the chill, so that the metal, as it rises in the mold in the direction ot the dotted lines, Fig. 4, will be free from agitation where it is in contact with the chill, and will at the same time have the desired rotation in the mold.

rlhe lower portion of the mold is prepared in the following manner, reference being had to Figs. 7, 8, and 9, Sheet 2, of the drawings.

rlhe wheel-pattern YV (shown in Fig. 8) has on the rim as many prints I as there are radial gates, and through the hub of the pattern passes a detachable cylindrical print, K, the lower portion, K', of which is removable from the upper portion. From that part of this print which is below the hub of the pattern radiate a number of rods, L, 011e extending to each print I, the inner end of each rod iitting in to a shallow recess on the central print above the movable portion K' ot' the same. rlhe rods L are similar to those which have long been in common use for the formation of curved passages or gates in the sand of molds, each rod being made inthe arc of a circle and with a slight taper, so that it can be easily withdrawn.

In Fig. 8 the sand in the lower boX ofthe mold has been properly embedded against the pattern and its prints, and around the rods L.

After withdrawing the pattern and the central print from the sand, the lower portion ot' the-mold will present the appearance shown in Fig. 9, nothing` remaining in the sand eX- cepting the rods and the lower portion, K', of the said central print, K. rllhe rods L can now be easily withdrawn in the direction shown by dotted lines, after which the lower portion, K', of the central printcan beremoved, and all that remains to complete the mold is to insert the hollow core B, Fig. 4, into its place7 and to introduce into the spaces left by the prints I sand-cores J, shown in perspec- P Each of these sand-cores contains the upwardly-inclined passage previously referred to, the said passage terminatingV below at m, where it coincides with the end of one of the passages formed by a curved rod, L, and above in the curved outlet n, which is concentric with the chill.

If desired, the prints I of the pattern may be dispensed with, and the sand-cores adjusted to their places before the sand is packed in the lower portion of the mold.

The manner of forming the upper portion of the mold will be too well understood by those skilled in the art to need explanation.

It will be observed that the chill H is hollow, and that there are pipes p and q, by which steam maybe admitted to and permitted to escape from the interior of the chill, Which is thus maintained at such a temperature that there can be no accumulation of moisture on the surface ofthe chill.

This heating of the chill would not of itself` prevent the formation of imperfections on the chilled tread of the wheel, but when the metal is caused to rotate in contact with the heated chill the full beneficia-l effect of the heat iinparted to the chill will be developed, and the soundness of the chilled surface of the casting will be assured.

I claim as my inventionl. The improved mode herein described of casting chilled wheels or chilled rims, the said mode consisting in causing the molten metal introduced into the mold to move in contact with the face otl a heated chill substantially as and for the purpose herein set forth.

2. In the process of casting chilled wheels or chilled rims, the mode of introducing` the molten metal into that portion of the mold which is bounded by the chill in upwardlyissuing streams concentric with the chill, but at a short distance therefrom, as set forth.

3. The combination, in a car-wheel mold, ot' a central pouring-gate, A, with gates E, each of which has an abrupt turn at a', and has a terminal portion, y, below the rim portion of the mold, and concentric with the chill, all as specified.

4. The combination of a car-wheel pattern, with the detachable print made in two sections, K K', and having recesses for the reception of the ends of the rods L L, as set forth. y

In testimony whereof l. have signed my name to this specilication in the presence of two subscribing witnesses.

GEORGE Gr. LOBDELL.

X/Vitnesses:

ALEXANDER PATTERSON, HARRY SMITH.

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