US2732599A

US2732599A - Molder s flask

Info

Publication number: US2732599A
Authority: US
Publication date: 1956-01-31
Anticipated expiration: 1973-01-31

Description

United States Patent slgnments, to Hines Flask Company, Cleveiand, Ohio, a corporation of Ohio Application April 9, 1951, Serial No. 219,953 1 Claim. (Cl. 22--11t!) This invention relates to molders flasks and particularly to an improved means for establishing and maintaining alignment between the two elements of the flask, commonly called the drag and cope. The invention is of that type where one member of the complete flask carries split pins adapted to slidably engage a recess on the other member to maintain a snug engagement and insure the cope being returned accurately to position after it has been removed for the removal of the pattern from the sand. Such split pins avoid the difliculty with a solid pin which is either too tight in the opening in the cope to allow it to be readily put in place or removed, or it becomes too loose, preventing accurate replacement of the cope, and such accurate replacement is especially necessary in precision casting, where it is desired to avoid subsequent machining of the article cast.

However, a difliculty has developed with such split pins that so infrequently the cope adheres so tightly to the pin carried by the drag that it requires jerking to loosen it, and such action is liable to disturb some of the sand. This invention provides means whereby the split pin may maintain its snug fit to hold the flask members in accurate registration and still may allow the smooth and easy separation without danger of dislocating the sand.

To the above end, I have provided a split pin carried by one member of the complete mold and extending through an opening in the other member and having a spreading tendency to cause a snug engagement therewith at all times, and I provide the pin with means limiting the spreading so that there is no danger of the pin so adhering to such other member that it is necessary to apply a jerk to separate the flask. The pin and its restraining means by which I accomplish the result is illustrated in the drawing hereof and hereinafter more fully explained and its features are definitely set out in the claims.

In the drawings, Fig. 1 is a plan of a flask employing my split pin construction, the corner clamps being omitted for simplicity; Fig. 2 is a vertical longitudinal section of the flask in an offset plane indicated by the line 22 on Fig. 1; Fig. 3 is a fragmentary elevation of my invention wherein the lower member of the flask is merely a plate adapted to carry the pattern; Fig. 4 is a perspective of a ring for limiting the spread of the split pin; Fig. 5 is a perspective of the upper portion of the split pin with the limiting ring mounted thereon.

As shown in Figs. 1 and 2, indicates the drag and 11. the cope of my flask. In Fig. 3 the drag is replaced by a flat plate 10a which may carry the pattern and the cope 11a is the full depth of the mold. In either case the i lower member of the flask carries my split pin 20, as by the drag arms 12 in Fig. 2 or a projecting portion of the pattern plate 10a in Fig. 3. The split pin 20 is adapted to extend through a bushing 30 carried by an arm 13 extending from the cope.

The split pin 20 is tapered at its upper end inwardly Patented Jan. 31, 1956 and upwardly, as shown at 21. In formed an annular groove which is occupied by a ring 25 which is split, as shown in Fig. 4. The slot in the split pin extends from the free end thereof nearly to the bottom and the arms of the pin are given a tendency to spread, the spreading being limited by the embracing ring 25. The external diameter of this ring is less than the diameter of the bodyportion of the split pin.

With the construction described, the pin maintains a snug engagement with the bushing 30. However, in removing the cope if there is any tendency to adhere to the this tapered portion is pm no erking action is necessary as the pin simply collapses slightly on an upward movement of the cope. Such collapsing action is not suflicient to release the ring 25 from the groove in the pin; it does, however, allow the cope to be readily moved off of the pin. As soon as the cope has been removed the spreading tendency of the split pin takes up the slack between the upper end of the pin and the ring and returns the pin to normal condition.

It will be seen that my split pin with the outward tendency of its arms restrained by the ring continuously provides means for accurately positioning the cope while allowing its ready placement and removal.

I claim:

In a molding apparatus, the combination of a mating pair of separable flask members adapted to be aligned in accurate registered relation with each other, one of said members having a receiving aperture along the axis of alignment, a pin carried at one end by the second member and extending in a direction parallel to the axis of alignment and through the receiving aperture for holding the members in accurate registered alignment with each other, said pin having a progressively increasing cross sectional area from said one end throughout the major portion of its length and tapering inwardly at the other end to a lesser cross section, said pin also having means for reducing the enlarged cross-sectional area by permitting the pin to the resiliently squeezed together for insertion into the receiving aperture, said means consisting of the axial portion of said pin having an open slit extending along its longitudinal axis from the inwardly tapered end throughout the major portion of its length and terminating short of said one end to form an integral base portion having a pair of outwardly diverging finger portions with inwardly tapered extremities, said finger portions being resiliently yieldable toward each other about a transverse axis through the split portion of a pin, the inwardly tapered surface of said other end of the pin being provided with a circumferential groove spaced from the pin extremity, and a ring occupying said groove to limit the spreading of the split end of the pin, the external diameter of said ring being less than the diameter of the integral base portion of said pin.

References Cited in the file of this patent UNITED STATES PATENTS 92,488 Strain July 13, 1869 113,313 Lipsey Apr. 4, 1871 124,071 Lipsey Feb. 27, 1872 956,621 Bogenschutz May 3, 1910 1,556,368 Sperry Oct. 6, 1925 1,611,161 Clerke Dec. 21, 1926 2,540,237 Bevin Feb. 6, 1951 2,641,033 Hines et al June 9, 1953 FOREIGN PATENTS 5,799 Great Britain of 1912 663,837 France Apr. 15, 1928 466.392 Germany Oct. 5. 1928 528,173 Germany June 26, 1931