US2423341A

US2423341A - Blowhole plug for sand boxes or containers

Info

Publication number: US2423341A
Application number: US620060A
Authority: US
Inventors: Axel H Peterson
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-10-03
Filing date: 1945-10-03
Publication date: 1947-07-01
Anticipated expiration: 1964-07-01

Description

July 1, 1947.

A. H. PETERSON BLOWHOLE PLUG FOR SAND BOXES OR CONTAINERS Filed Oct. 3, 1945 IEEE.

INVENTOR. flH. Pelemozz V ATTORNEY Patented July 1, 1947 umrso BLOWHOLE PLUG FOR SAND BOXES on CONTAINERS Axel H. Peterson, Rock Island, 111. Application October 3, 1945 Serial No. 620,060

My present invention relates to molding apparatus and more particularly to improvements in sand boxes or containers for molding sand. Specifically, my invention relates to means for preventing the escape of sand and air between the sand box and, for example, a core box, when sand is being blown from the sand box to the core box. It is a common experience in molding to find that the, metal parts do notfit together closely enough to prevent air from blowing through between the bottom of the sand box and the top of the core box, said air carrying with it fine sand which scores the adjacent metal parts, thus causing an increase in leakage of air. I have found that, by enlarging the blow hole in the bottom or base plate of the sand box, tapping the same, and putting through this hole a screw-threaded plug formed from a substance such as neoprene or a combination of neoprene andmetal, with the synthetic extending slightly below the bottom of the bottom plate, a sufliciently tight engagement can be made around the blow hole to prevent air from escaping between the plug and the core box, thus eliminating this blow-by.

In the drawings annexed hereto and forming a part hereof, f

Fig. 1 represents, fragmentarily, a vertical, longitudinal section of a core-forming machine embodying my present invention;

Figs. 2 and 3 represent, respectively, a plan view and a longitudinal section of one type of plug which I have produced for the purpose stated;

Figs. 4 and 5 represent, respectively, a plan view and a longitudinal section of another form of this plug; and

Figs. 6 and '7 represent, respectively, a plan view and a longitudinal section of still another form of this plug.

Reference will now be made in greater detail to the annexed drawings for a more complete description of this invention. The sand box is shown at I and it will be understood that this is merely typical of many forms of sand boxes now well known in the art. At 2 is shown the bottom plate which is secured to the sand box by bolts 3, in a manner comparable to that disclosed in the Demmler Patent No. 1,480,747. By enlarging the blow hole in the plate 2 and tapping this, as shown at 4, it is possible to screw into this opening a screw-threaded

plug

5a, 5b, 50 or a similar plug of some other form. I have chosen to illustrate a core box 6 as comprising upper and lower parts 6a and 6b which are detachably connected by the dowel pins I. This core box is shown as resting on a platform 8 which may be raised to press 1 Claim. (Cl. 22-16) the upper surface 9 against the lower edge of the plug, with the holes I'll and H in registry. It is not necessary to have the plug extending much below the plate 2 as it is only necessary to have a tight fit between the surface 9 and the lower end of the plug so as to prevent air blowing out between them. i r

I have shown the plug in Figs. 3, 5, and '7' in three diiferent forms, the first two being composite plugs while the last is constructed entirely of a suitable synthetic composition, preferably neoprene. Each of these plugs is shown as having the upper end of the hole I I enlarged and-formed as a hexagon, in cross-section. This is in'order that a tool of proper form may be inserted in the opening and turned for the purpose of screwing the plug into or out of the hole 4.

The plug of. Figs. Z'and 3 is shown as having an upper metallic section M with a lower reduced portion '13 to which is bonded a section Idofv neoprene which continues the general form of section I2, the threads of the two sections being identical in shape and continuous so that it is possible to screw this plug into the base plate 2, as shown in Fig. 1. This plug should extend somewhat beyond the lower face of the plate 2 and, preferably, should not extend above the top thereof. Therefore, when the core box 6 is pressed upwardly against the plug, the neoprene yields sufiiciently to form a tight seal entirely around the apertures I0, II. This will keep air from blowing out between the core box and the plug and will reduce to a minimum the amount of scoring of the face 9 and any abutting parts. As shown clearly at I5, the upper end of the hole I I is somewhat enlarged and is hexagonal in form,

thus making it possible to insert a suitable wrench for the turning of the plug.

The plug of Figs. 4 and 5 differs somewhat from that of Figs. 2 and 3 in that the body of the plug is substantially entirely of neoprene with just a liner extending substantially from end to end of the plug. The upper end of the enlargement of the hole II is, preferably, flared somewhat in order to mak it easier to insert the wrench, as well as to reduce the friction between the plug and the sand entering the hole II.

The plug of Figs. 6 and '7 is made entirely of a yielding, non-metallic, synthetic material, for example, neoprene, and is shown as having the same external configuration as the other two. This, as well as the other two plugs shown, will yield when the core box is pressed against it, thus causing a tight fit and preventing any blowby of the air.

While I have shown three forms of embodiment of the present invention, I have embodied this idea in several other forms and the present disclosure is therefore to be regarded merely as illustrative, rather than showing the entire scope of this invention; however, I prefer the type of plugs shown in the present drawings.

While I prefer plugs of generally cylindrical configuration with screw-threaded exterior surfaces fitting in holes of the same general form in the plate 2 and provided with cooperating screw threads, it will be understood that various other embodiments of this idea are possible. For example, plugs of generally spool-shaped configuration provided at their ends with outwardly extending flanges may replace those shown in Figs. 2 to 7, inclusive. The hole in the plate 2 would have its ends countersunk for the reception of the flanges of the plug in order that the plug would be held in plac against longitudinal pressure, either up or down. Of course the lower end of this plug would need to project slightly beyond the bottom of the plate 2. Another form of plug would be one having its middle portion of greater diameter than its two ends, the hole in the plate being under-cut to accommodate the shape of the plug. Another form would be the reverse of that just described, in which the middle part is small in diameter while the two ends are enlarged. In such a case, the plate 2 would need to have the hole 4 reamed out upon opposite sides so that the conical surfaces of the plug would fit the faces of the metal.

The base plates can be formed with holes of different shapes therein and can have the plugs molded in these holes and vulcanized in place, with the lower end projecting slightly beyond the face of the base plate. This would avoid the necessity of enlarging and tapping the hole 4 for the insertion of threaded plugs, if one wishes to be: spared the necessity of this extra work. However, I prefer the use of screw-threaded plugs as set forth herein.

A simple way of accomplishing the desired end is to provide a base plate with a hole therethrough, as described above, and then counterbore the underside of this plateso that the hole through the plate has an enlargement at its lower end. A suitable washer, slightly larger in diameter than the counterbore and made of a suitable yielding synthetic material, may then be inserted in the counterbore, with its lower portion projecting slightly beyond the face of the plate. Then, when the core box i pressed against this, the space between the sand box and the core box will be adequately sealed'against blow-by.

It will of course be understood that the specific description of structure set forth above may be departed from without departing from the spirit of my invention as set forth in this specification and the appended claim.

Havin now described my invention, I claim:

In a maclr'ne of the character stated, a sandfeeding box provided with a bottom plate having a screw-threaded sand delivery opening, and a liner, yieldable at its lower end and externally screw-threaded throughout its length, screwed into said opening and projecting slightly beyond the bottom surface of the plate, said liner having in its upper end a non-circular opening for the reception of a wrench whereby the liner may be screwed into and removed from the opening in the plate, and said non-circular opening having an extension reaching to the lower face of the liner and serving to deliver sand to a core box or other place of use.

AXEL H. PETERSON.

REFERENCES CITED The following references are of record in the file "of this patent:

UNITED STATES PATENTS Germany Mar. 30, 1937