US1562509A

US1562509A - Permanent-mold construction

Info

Publication number: US1562509A
Application number: US10830A
Authority: US
Inventors: Harry S Lee; Amos E Chaffee; Millard Fred
Original assignee: Individual
Current assignee: Individual
Priority date: 1925-02-21
Filing date: 1925-02-21
Publication date: 1925-11-24
Anticipated expiration: 1942-11-24

Description

Wm 24, H. 8. LEE ET AL.

PERMANENT MOLD CONSTRUCTI ON Filed Feb. 2l, 1925 2 Sheets-Shwkl v klVV NTORS dry 66 y 1 #4020555? Wee BY 7 66? M'Zza rd A TTORNE Y.

Patented Nov. 24, 1%25.

\ UNITED HARRY S. LEE, All [0S E. CHAFFEE, AND FRED MILLARD, OF IPL'YEOUTH, MICHIGAN; ASSIGNORS OF THEIR ENTIRE BIG-HT TO THE 1 SAID GHAFFEE AND SAID MILLAED 8AM) LEE.

ATENT? OFFICE.

PERMANENT-MOLD CONSTRUCTION.

To all whom it ma concern:

Be it known that we, HARRY S. LEE, Amos E. CHAFFEE, and Fnnn MILLARD, citizens of the United States, residing at Plymouth, in the county of. Wayne and State of Michigan, have invented certain new and useful Improvements in Permanent-M0ld Construction, of which the following is a specification.

This invention relates to mold construction, and more particularly pertains to molds provided with means whereby the meeting faces of the molds are automatically adjusted so that the same will remain perfectly parallel, and therefore always meet.

With all molds, and especially so with molds that have a greater relative length than width, it is the tendency of them to how when heated. These molds are subjected to very high temperatures, as the metal which is poured therein has a temperature of approximately 1700 to 2000 degrees Fahrenheit. This causes the face of the mold to become extremely hot while the rear of the mold has a less temperature. This causes the mold .to expand and when the mold is rigidly secured to the carrier or support this expansion will cause the mold to bow out. To overcome this tendency it is customary to only secure the mold to the support at one point thus allowing for expansion, in all directions parallel to the face.

of the mold. However, it is found that the face of the mold expands at a greater rate than the rear of the mold which is more remote from the casting, due to the tact of the difierence in temperature. This difi'erence in expansion tends to bow out the mold or warp the same and it is found that the faces of the molds are not parallel, and prevents the mold from forming a perfect joint.

Our invention pertains to means for controlling this warping or bowing action in such a manner as to counteract the tendency of the mold to bow due to the difl'erence in the rate of expansion between the face of the mold and the rear portion of the mold.

In the drawin s:

Fig. l is an e evational view ofthe face of a mold which has a considerable length as compared with the width.

Fig. 2 is a vertical section on the lin 2-2 of Fig. l.

Fig. 3 is an enlarged detail of one end of the mold showing the die expanded.

.Fig. 4 is an enlarged modified detail of one end of the mold showing separate regulatable means for controlling this expansion.

Fig. 5 is a view similar to Fig. 4, but showing the die expanded. I

This mold consists of two partsa subhead a and a die 6. This die is provided with a molding cavity 0 and the hot metal is poured therein. Tn the drawings T have shown only one half of the completed mold as the other half is an exact duplicate and will be abutted up against this half and properly located by the dowel pins d. These dies are so machined and finished that they will abut each other and tightly fit against each, other to prevent any leakage of the molten metal from between the abutting faces of the dies. @bviously the molds can be of any shape, large or small and we do not limit ourselves to the specific form of mold shown in the drawings.

To counteract the tendency of the die to how when heated during the time when the casting is poured, we provide the inclined bearing faces 6 on the subhead and the hearing laces f on the die which are complementar'y to the bearing faces on the subhead. The die is secured to the subhead at an intermediate point by the screws or bolts 9, and the ends of the die are secured to the subhead by the screws h but the die is pro- ,vided with anelongated slot 2' which permits the ends of the die to freely slide with respect to the subhead. As the die expands in a direction parallel-to the face of the die due to the change in temperature the inclined bearing face of thedie will ride up the inclined bearing face carried by the subhead, as shown in Fig. 3, and this will force the free ends of the die toward each other to counteract the tendency of the die to bow outwardly. This will maintain the face of the die in substantially parallel relation with the face or the mating die and prevent leakage of the molten metal, @bviously this control means could be located to correct warping or bowing from side to side as well as lengthwise Tu Figs. 4- and 5, we show a modified form of construction in which the expansion plug is" is inserted in the subhead and, rejects through the inclined bearing face, a screw m is backed up against'the rear of the expansion plug and by screwing the same in or out the expansion plug may be adjusted. This expansion plug may be formed of any metal that has a greater ratio of expansion than the metal of the mold, such as aluminum, brass, bronze or steel plugs. This plug when heated expands at a greater rate than the subhead, and as shown in Fig: 5, this bears against this inclined bearing face carried by the die, and exerts a pressure transs versely of the die at the free ends to counteract the tendency of the die to bow. With such an expansion plug abetter control of the mold may be had, asthis expansion plug may be adjusted mechanically and by using plugs of different material the same may expand at a greater or less rate. This gives us an automatic thermostatic control of the mold in addition to the mechanical control so that the machined faces of the molds remain perfectly parallel. The location and numberv of these expansion plugs depend upon the size and shape of the mold.

Such a control is especially desirable when using molds which have a. much greater dimension in one direction, but such a control can be used with molds of any size or shape, and in fact we are using such a construction in all of our molds as there is always a slight tendency of the molds to bow, no matter what their size and shape is.

This application is directed to the automatic control of mold section distortion in permanent molds, regardless of the direction of bowing or distortion. It is more particularly directed to the accomplishment of this-purpose by means of interposing a mechanical element for furnishing a countervailing effort tending to neutralize these distortions. There are claims involved in this case which refer to the use of a thermally responsive element in connection with the special mechanical design for affording the countervailin efi'ort. However, the particular princip e of counteracting the distortion of the mold section by a thermally responsive element is not broadly claimed in this application except so far as it may be covered b the broad claims for the automatic contro of the distortion. The utilization broadly of thermally responsive elements to eifect this control is considered a separate invention and is claimed in application Serial No. 39,053, filed June 23, 1925.

What we claim is:

1. A mold, having in combination a support, a die secured thereto and permitted to expand and tending to bow when heated, and automatic means for applying pressure transversely of the die when the same expands to counteract the tendency of the die to bow as the result of such expansion.

2. A mold, having in combination, a support, adie secured thereto and permitted to bearin expands to counteract the tendency of the die to bow as the result of such expansion.

3. A mold, having in combination, a support, a die secured thereto at an intermediate point and permitted toexpand and tending to bow when heated, and automatic means for applying pressure at the ends of the die and transversely of the die when the same expands to counteract the tendency of the die to bow under such expansion.

4. A mold, having in combination, a support, provided with one or more inclined bearing faces near the outside edge, and a die secured near the center to said support and provided with inclined bearing faces near the ends complementary to and engaging the inclined faces on the support, said die permitted to expand and tending to bow when heated, thereby causing the inclined faces on the die to ride up the inclined faces of the support, whereby pressure is applied at the ends of the die and transversely thereof to counteract the tendency expanded.

5. A mold, having in combination a support provided with one or more inclined bearing faces near the outside edge, adjustable means for correctly positioning said bearing face, and a die secured near the center to said support and provided with inclined bearing faces near the ends complementary to and engaging the adjustable inclined faces on the support, said die ermitted to expand and tending to bow w en heated, whereby the inclined faces on the die are caused to ride up the inclined faces on the support, to apply a force near the end of the die transversely thereof to counteract the tendenc of the die to bow when heated and expan ed.

6. A mold, having in combination, a sup port provided with one or more inclined faces near the outside edges, thermostatically controlled means for positioning the said bearing faces, and a die secured near the center to said support and provided with inclined bearing faces near the ends complementary to and on aging the inclined faces on the support, said die permitted to expand and tendin to bow when heated, whereby the incline faces on the die are caused to ride up'to the thermostatically controlled inclined faces on the support to counteract the tendency of the die to bow when heated and expanded.

7. In a mold, the combination of a die which expands and tends to how when heated, and automatic means for controlling the tendency of said die to bow.

8. 'In a mold, the combination of a die which expands and tends to bow when heatof the die to bow when heated and ed, and means for automatically applying which when heated-expands in a direction pressure transversely of said die to counterparallel to the plane of thedie and tends to act the tendency of said die to bow. bow, and means for automatically applying 9. In a mold, the combination of a die a pressure transversely of the plane of said '15 5 which is caused to be heated to a higher die to counteract the tendency of said die temperature on one side than on the other to and thereby expanded unequally thus tend- I 1 t st m ny whereof We have afiiXed our ing to how the die,.and automatic means g for correcting the tendency of said die to HARRY S. LEE. 10 how. r AMOS E. CHAFFEE.

10. In a mold, the combinationof a die FRED MILLARD.