US576246A - Method of and apparatus for forming sand molds - Google Patents

Description

Patented Feb. 2, 1897.'

l s. J. ADAMS. MBTHDD 0F `AND APPARATUS FOR FORMING SAND MOLDS. No. 576,246.A

(No Model.)

NTTED STATES PATENT OFFICE..

STEPHEN JARVISADAMS, OF PITTSBURG, PENNSYLVANIA.

METHOD OF AND APPARATUS FOR FORMING SAND MOLDS.

SPECIFICATION forming part of Letters Patent No. 576,246, dated February 2, 1897. Application filed February l5, 1893. Serial No. 462,365. (No model.)

To @ZZ whom t may con/cern.'

Be it known that I, STEPHEN JARvIs ADAMS, a resident of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in the Method of and Apparatus for Forming Sand Molds; and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to the making of molds of two or more parts, that is, the making of the ordinary cope-anddrag mold, though it may be employed with advantage with molds having more than two parts. It is a wellknown fact that in the making of such molds difiiculty is experienced in bringing together the different parts of themolds so that they will coincide exactly, this difficulty arising particularly from the fact of the wearing of the guide-pins and seats on the flasks and loosening of these fittings thereon, as the iiasks are handled roughly, being piled up on the foundry-floor and very lia-ble to topple over, while the pins extend out beyond the body of the liask and are liable to strike against the adjoining iiasks or on the foundry-Hoor, thus leading to the breaking or loosening of the pins which aifect the proper guiding of the two parts of the mold together, as even if the two parts are properly separated there is liability that the parts will not be brought together properly in closing the the mold. In addition to this the `wood of which these iiasks are generally made is liable to shrink and swell, as the sand is moist, and for this reason the flasks often get out of shape. All these difficulties lead to the imperfect matching of the two or more parts of the mold, so that the mold-cavities are not brought into proper line with each other and imperfections and irregularities in the shape of the casting are caused thereby, which often lead to the loss of a large amount of the castings formed. This work is necessarily done rapidly, and the workmen are somewhat careless about the work, and even when careful the loosening of the fittings and like causes lead to the formation of many irregular and imperfect castings.

The object of the present invention is to provide for the guiding of the two parts of 'the mold together by guides formed at the time that the molds are made and which are entirely independent of the usual guiding means found upon the `liasks themselves.

To these ends my invention consists, generally stated, in forming the guiding means within the bodies of the molds when molding the same and guiding the one part onto the other part by pins projecting from one part and entering guide-holes in the other part and then withdrawing the guide-pins from the completed mold, such as by forcing the guide-pins through the bottom of the completed mold. Such guide-holes being formed in the sand of the mold are, of course, formed each vtime that arnold is made, and it is evident that the two parts of the mold, when guided in this way to place, necessarily coincide perfectly,"so that a perfect matching of the mold is obtained and the difficulties leading to imperfect matchings, as above set forth, are overcome.

It also consists in certain improvements in the apparatus employed, as will be hereinafter more particularly described and claimed.

To enable others skilled in the art to practice my invention', I will describe the same more fully, referring to the accompanying drawings, in which- Figurel is a vertical section illustrating one method of forming the two parts of the mold. Fig. 2 shows the mold separated, with the guide-pins in the lower part or drag of the mold, showing also the cope of the mold above the drag in position for the entering of the guide-pins within the guide-holes of the cope. Fig. 3 shows the two molds together and also illustrates the preferred method of withdrawing the guide-pins, such as by forcing them through the bottom of the mold. Fig. 4 is a top view illust-rating the method of bringing the mold parts into proper position, so as to bring the parts of the mold into approximate line for the entrance of the guidepins within the guide-holes in the mold-body. Fig. 5 is a view illustrating the invention as applied to cores, and Figs. 6 and 7 are detail views.

Like letters of reference indicate like parts in each.

I have illustrated the invention in connection with the two-part or cope-and-drag mold which is a simple form with which it may be employed and sufficientlyillustrates it to enable its application to more complicated molds to be understood.

In Fig. l the drag-tiask a and cope-flask b are illustrated surrounding a mold in which the compacting of the sand has been completed, the mold being formed of the drag a and cope ZJ, the pattern c being attached to a pattern-plate d, which pattern-plate carries the guide-patterns e. e for forming the guideholes ff within the sand of the two parts of the mold, it being preferred that the patterns e e' be rigidly secured to the plate. The mold rests upon the bottom board g. The drawings also show stripping-plates d', which are preferably employed with the pattern in order to provide for the stripping of the pattern from the mold, though suoli strippingplates need not be employed. The guidepins c e are simply cylindrical bars, which are formed as shown in Fig. Il, being bars preferably of the same diameter, one having a threaded pin entering a threaded socket in the other, and the pin extending through a hole in the pattern-plate, so that the socket maybe screwed upon the same, the two parts of the guide-patterns being thusbrought into exact line with each other, and the construction being such that they can be formed to exactly coincide with each other and to occupy positions on each side of the patternplate exactly coinciding with each other. In making such a mold the pattern-plate and stripping-plate for the drag are properly supported, the drag-flask being placed over the same and that part of the mold compacted and the bottom board placed upon the same and the mold turned over, and then the other stripping-plate is placed upon the patternplate and the cope-flask placed thereon and the sand compacted within the cope, it being preferred that the guide patterns or pins extend, at least in the cope, to the upper end thereof, though that is not absolutely necessary. It is not necessary that the cope and drag fiasks shall occupy any special position with relation to each other on the patternplate, though of course they are naturally made to fit approximately with each other and in approximate position with relation to the pattern itself. The cope is then lifted from the pattern, being lifted by means of the stripping-plate, if such is employed, and being guided in its movement by means of the guide-patterns e e'. The pattern is then.

withdrawn from the drag, being guided in its movement by the guide-'patterns e c', the stripping-plates of the cope and drag being removed after they are separated from the patterns, as above described. rPhe operator then places the guide-pins t within the guideholes f of the drag, as shown in Fig. 2, such guide-pins extending above the drag, and the cope is then lifted and brought over the drag, so that the guide-pins enter the guide-holes f formed in the cope, and the cope is gradually lowered to place, being guided in its movement by such guide-pins, and in this way the two parts of the mold are brought to exact line with each other.

The above description gives a general idea of one manner of practicing the invention, though some changes may be made therein, such as Where both parts, cope and drag, are molded on the same patterns, or they are molded on different patterns having guidehole patterns coinciding with each other, which mold is illustrated to the right of Fig. l, or the guide-hole patterns, though carried by the pattern-plate, are not rigid therewith, but it in seats therein and p roject on both sides thereof, as shown to the left of Fig?. 1, and after the cope is removed the pattern is removed, leaving the patterns or pins projecting above the drag, as shown in Fig. 2, and so form the guide-pins to enter the guideholes in the cope.

In order to bring the cope and drag approximate-ly into line, I employ the guideframe r for the outer bodies of the mold parts, which may be of any suitable form, that illustrat-ed being one vertical portion r', with a vertical portion r2 extending out for a short distance at one end thereof, the drag-flask being placed against the guide with its back against the portion 0" and its end fitting against the portion r2, and the cope raised andplaced in the same position, so bringing the guide-holes f above the pins il with suflicient accuracy to insure the pins entering the holes, so that the accurate guiding within the mold-body may be effected.

For the purpose of withdrawing the guidepins after the completed mold is thus closed I prefer to form in the bottom board k the openings 7a in line with the guide-holes, and after the completion of the mold to simply force the guide-pins from the completed mold by pressure on the upper ends thereof by any suitable tool, the guide-pins being thus used again and again. For all ordinary purposes the sand itself will be sufficiently rigid to form a guiding means, but if desired suitable sleeves may be employed, which are embedded within the sand during the molding operation and which themselves form the interior of the guide-holes formed in the moldbodies. This is shown in the figures at one side of the mold, the sleeves being placed over the guide patterns or pins before the IOO IIO

sand has been compacted within the mold, the sand being compacted around such guiding-sleeves l, and when the patterns are withdrawn these sleeves ZZ' are left within the rcspective mold parts and the guide-pins enter within such sleeves, and such sleeves receive the pins as the one part of the mold is closed upon the other. These sleeves maybe formed with vertical wings Z2 thereon, as shown in Fig. 7 and in dotted lines in Fig. 4, which will assist in holding them more rigid and in perfect line within the mold-bodies and yet will not interfere with their withdrawal from the same, and if desired they may be provided with tapering outer surfaces, at least as to the lower sleeves, so as to enable them to be separated from the sand easily by pressure in the direction of their length.

In order to preventthe sand from entering the sleeves and filling the same during the molding operation,the lower sleeves may have closed ends, as shown at Z3, and the upper sleeves may have like'closed ends or with removable caps Z4, which may be placed in position during the molding operation, and removed, if necessary, as when the guide-pins are desired to pass through the sleeves, as when making a mold of more than two parts, that is, the building up of a series or a number of separate parts on the drag part, or for the forcing out of the guide-pins.

After the molding operation is completed the guide-pins, with their sleeves, may be forced out of the mold-bodies by direct pressure thereon by an instrument, such as employed with the guide-pins themselves. These guiding-sleeves may be only employed with the upper mold part or with the lower mold part, as found desirable.

Like means may be employed in placing together the class of cores which are desirably or may be necessarily formed in halves, and which have been heretofore secured together by pasting, or like means, the guide-pins being placed within like guiding-holes in the edges of the half-core or body of drag part of mold beyond the mold-cavities, the core or half-core slipped on same to their seats in drag part of mold, and the other half-core lowered and guided to place by such guide-pins, this being shown in Fig. 5, in which the corehalves m m have the guide-holes n formed therein, and the guide-pins p are employed within such guide-holes to bring them into proper line. As these cores are formed in the core-boxes, the guide-patterns may be formed with the coreboxes, and perfect guiding means be thus obtained for the handling of the cores. Such construction is included within this invention, as of course the terni mold parts. includes such cores as well. By such simple means I am thus enabled to bring the two parts of the mold into exact coincidence, the guides for the same being formed at each formation of the molds themselves and by means of the Vparts rigid with the patterns or their plates and which are not liable to displacement, while as such guideholes are formed with each part of the mold and receive the guide-pins,as above described, the actual guiding of the parts to place is thus insured, and all liability of imperfect matching on account of the wearing or loosening of the flask-guides or warping of the flasks themselves is overcome. At the same time, as the means are simple they require little or no time for their employment and give to the operator guiding means for the entire length of the mold part, which overcomes the necessity of such careful handling of the mold in closing the same.

What I claim as my invention, and desire to secure by Letters Patent, is-

l. The herein-described method of forming the two-part molds and guiding the parts to place, consisting in forming the guiding means within the bodies of the mold parts when molding the same, and guiding the one mold part onto the other mold part by pins projecting from the one mold part and entering holes in the other mold part, and then forcing the guide-pins through the bottom of the. completed mold, substantially as set forth.

2. In sand molding apparatus, the combination of a two-part iiask, and a pattern-plate carrying the pattern of the article to be molded and guide-patterns on each side thereof in line with each other and entering within the flask parts, substantially as set forth.

3. In sand molds, the combination of one mold part having guide-holes formed therein provided with sleeve-linin gs and another mold part having guide-pins fitting in such lined guide-holes of the one mold part, such sleevelinings having closed ends whereby they may be forced out of the nished mold7 substantially as set forth.

4. In sand molds, the combination of one mold part having guide-holes formed therein provided with sleeve -linings, and another mold part having guide-pins adapted to enter such lined guide-holes of the one mold part and to act as guides for bringing the other mold part to place, such sleeve-liningsbeing provided with lon gitudinally-extending wings to sustain the same within the body of the mold, substantially as set forth.

5. In sand molds, the combination of thev two mold parts each having guiding-holes formed in the sand thereof in line with each other, guiding-pins fitting in such guide-holes and a botto m board supporting the lower mold part and having openings therein to permit the withdrawal of such guiding-pins, substantially as set forth.

(i. In sand molds, the combination of the two mold parts each having guiding-holes formed therein in line with each other, guiding-pins tting in such guide-holes, a bottom board supporting the lower mold part and IOO IIO

ed to bring the guide-holes approximately in line With the guide-pins, substantially as set forth.

In testimony whereof I, the said STEPHEN JARVIS ADAMS, have hereunto set my hand. 15

STEPHEN JARVIS ADAMS.

Titnessesz v JAMES I. RAY, J. N. COOKE.'

Images