US 1912931 A
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Description (OCR text may contain errors)
June 6, 1933.
N. s. CLAY 1,912,931
MOLDED ARTICLE 1 Filed May 17, 1928 '4 Sheets-Sheet 1 INVENTOR' 1 ATTORNEY June 6,1933. v N 5 cu I V 1,912,931
MOLDED ART I CLE Fil ed May 17, 1928 4 Sheets-Sheet, '2
INVENTOR 9 A'i'TORNEY June 6, 1933. I N. 5 CLAY 1,912,931
MOLDED ARTICLE File'dj"May '17, 1928 j%/%fi jz /4il /4 x W T .NVENTO BY a d; ,%44 I 5. ATTORNEY 1 4 Sheets-Sheet 3 June 6, 1933. N. sfcLAY MOLDED ARTICLE Filed May 17, 1928 4 Sheets-Sheet 4 INVENTOR A/ AfTORNEY Patented June 6, 1933 UNITED STATES PATENT 'Q F E.
NOBLE s. CLAY, or wrnxmsnune,
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L uommn ARTICLE Application filed Kay 17, 1928. serial a... 278,513.
My invention relates to. composite products and it has particular reference to trays.
of composite material that are particularly adapted to cafeteria service. the prior art have been made of certain metallic materials, such as aluminum andthe like. Trays made ofthis material have the disadvantage that they arev noisy, oxidize readily and that Itis, therefore, an object of my invention to provide a tray in which theabove disadvantages are entirely obviated.
Another object of my invention isto provide a tray which is pleasing to the ermits of ornamentation. Still another object of my-mvention'is to provide a tray which is'sturdy in construction and low in cost of manufacture. After considerable experimentation, I have succeeded in producing a tray made of laminated material consolidated with a heat-hardened binder and find that the tray so produced has especially desirable characteristics. The invention may be better understood by reference to the accompanying drawings, m
Figure 1 is a view, in perspective,of a finished tray madeaccording to my method of manufacture,
ploded view of the sheets,
Fig. 2 is an ex of treated material as they are assembled preparatory to molding according. to one of my methods of manufacture,
Fig.2 is a view,- partly in elevation and partly in'section, of the dies Ofdl press, with the necessary material assembled. therein,
preparatory to the mold'ng of a tray, I
Fig. 4 is a view, partially inelevation and 1 partially in section, of the dies of a press and the tray during the process of molding,
Fig. 5 is aview, in section, of a part of the tray, showing the upturned flange portion, and manufactured according to, one of my methods of manufacture, V
Fig. 6, Fig. 7 and Fig. 8 show portions of the dies of a press, together with the necessary material, for maklng trays according to a modified method of manufacture,
Fig. 9 is a view, partly in top elevation and partly 'in .section, taken along the line Most trays of dirt clings to theirsurfaces.
eye and p the corners of the finished trav.
IX-IX of Fig. 10, and showing a tray made according to a modified method of manufacture,
Fig. 10 is a view, a tray made according to a modified method of manufacture, Figs. 11 and; 12 are views, in elevation, illustrating'examples of methods of cutting the corners of the sheets in order to avoid ex 7 cess material at the cornersof finished-trays,
molding, in order to avoidexces's material .at
Referring more particularly Fig. 13 is a view, in perspective,showing a. method of forming the-sheets preparatory to I to 1 and in section, of a portion of 2, .I have found it desirable to make the tray 1 Iof a plurality of layers of suitable treated cloth and 'm I, shredded or chopped condition, may also'be.
fibrous material, subh as paper, the like. .Treated' Efibrous material, in a used. The preferred treating material or impregnating binder is a phenolic condensation product, although other being hardened under the action of heat may be utilized.
Sheets of different lized, as,
for the bottom .cover, four body or filler sheets binders capable or v dimensions may be utifor instance, a prefe'rredstructure would embody four sheets 2 of treated paper i 3 of the same size as the bottom of the finished tray, four body or filler sheets 4 of a size intermediate that of. sheets 2 and sheets 3 and four full-size upper-cover sheets 5. The cover sheets 2 and 5. are preferably treated with a higher content of binder than are the sheets in the interior of the tray. f t
If desired, inserts, such as terial 6, or pieces of wires orflth like may be utilized to provide a thicker edge portion or lip for the-tray. These strips are arranged in the form of ho'I-a 10w rectangles, and be reinforcedby special reinforcing suchas the triangular corner pieces 7. Furthermore, various shaped pieces of material, such as triangular pieces, may be removed from the corners of certain of the sheets as shown in Fig. 11, or the corners may be slotted (Fig. 12) to provide strips of material, which strips of matreated or untreated rope,
the corners thereof may A sheets,
may be overlapped asshown in 13, to pertion 22, shown in Fig 35 mit better fitting of the sheets the mold and reduce the amountof material at the corners of the finished tray.
If desired, small insignia sheets 8, (Figs. 1 and 2) on' which various designs are printed, may be placed either just inside the bottom surface layers or under the top surface layers. As an alternative, full-size surface-sheets upon which the utilized. After the hardening "treatment, this insignia will be found to be plainly'visible through the superposed material of the tray. In this manner, I may provide variously decorated or colored cover sheets in order to give the tray a decorative appear ance, such as that obtained .with highly' polished wood finishes and the'like. The trays are molded, underheat and pressure, in the usual manner and any excess material at the corners trimmed away.
The sheets are assembled in the order shown in Fig. 2 and stacked on the-lower die 13 of the mold shown in Fig. 3, the sheets bendingdownward at the center by reason of their own weight. Themold is closed, as in Fig. 4, and heat and pressure applied, in the usual manner, to harden the binder and consolidate the laminations. The closing of the mold causes the edges of'the various sheets to be crumpled together or conglomerated to fill the edge portions of the mold, thus providing the folded, thickened or conglomerated edge por- 5. -A -modified method of manufacture is shown in Figs. 6, 7 and 8. In this process, the
sheets of treated material 11 are all of thesame size, the dimensions being such that the sheets are slightly larger than the total. lower surface area of the finished sixteen sheets are utilized but, of course, any
' other number of sheets may be employed, ac-
1 ledge; 18 of cording to the character of the material and the desired thickness of the finished article. Special dies, such as the dies 12 and 13 shown in Fig. 6, are. employed. The upper die 12 is rece'sed at its outer rtion 14, so that a hollow rectangular mem r. 15 may be placed on the lower die between the flanges 16 and 1']. The rectangular member 15 is provided, at its upper inner edge, with a ledgelS large enough and deep enough to receive the sheets of treated material, provided with an innersurface portion 19 sfloping downwardly and inwardly thererom. V v In making a tray according to the second method, the treated sheets are placed on the the rectangular member 15 of the dies. The mold is then closed. This action pushes the sheets into the recess 20 of the lower mold, bending them upwardly at the edges (Fig. Since the-weight of the sheets causes them to bend downwardly at the middle, (Figs. 6 and 7) the slightly overinsignia is printed may be tray. Preferably,
-1nclusion is and'it'is further b I claim as my invention:
rial rests upon the bottom of the size sheets are entirely ing between the dies. As the mold is closed, the convex portion 21 of the sheets is flattened out, and the excess sheet material forced into the side wall opening of the mold, where it is scraped down the wall 19 of the rectangular member 15 and crumped and folded to pro- .vide the thick beaded edge portion 22 of the tray.
The corner wall 0 enings (not shown) between the dies of the mold are of greater thickness so that the excess material at the corners of the sheets may be crumpled and folded, in the same manner as the bead, to provide a thicker wall secti n 23 (Fig. 9) of folded or conglomerated material at the corners of the tray tobetter withstand shock, and in order to permit the utilization of ordinary sheets without cutting out certain as has been hitherto described.
olding under heat and pressure is then carried on, in the usual manner, to complete the process. The corner made according to this process is shown in Figs. 9 and 10.
I have found, in manufacturing the trays, that great care must be used in the treatment' of the sheet material and that, if.the treating operation and molding operation are not carefully practiced, blisters are likely to form after the molding operation. I have found that this difficulty may be obviated by close attention to the operation of treating the sheet materia It has been found that blistering is ordinarily caused by the volatile matter included in the binder and that, if thesheets, prior to molding, are carefully dried at a temperature of from 90 to 120 for from 10 to 30 minutes, this difliculty is obviated. The cover sheets, the binder content of which is relatively high, must be closely watched, as regards the volatile matter inclusion. .If the kept under 4%, blistering is not likely to occur.
. A tray made according to my method of manufacture will be found to be easy to clean,
noiseless, pleasing to the eye and low in cost of manufacture.
Although I have described certain preferred processes and structures, ent that .further' modifications may be made y those skilled in the art without departing from the spirit and scope of my invention as defined in the appended claims.
1. The process of forming tra s -'which comprises placing fibrous materiafi impregnated with a binder capable of beinghardened under the influence of heat and 1n the matrix ofa mold in such a manner contained in the openportion of a tray it is appar-' pressure,
that a major proportion of the fibrous matethe remainder extends upwardly at an angle thereto, f'ormmg an edge portion havinga mold and substantially flat up er itaneously applying stantially perpendicular to the plane of the surface, and simuleat and pressure subangular extending material and substantial-. ly vertical pressure to the material resting on the bottom of a he mold and to the edge of the, upwardly extending edge portion, sufli-.
cient pressure being applied to forma composite article having upwardly extending sidewalls and an outwardly extending peripheral flange.
. and contour sheets will be foldedupwardly at an angle 2. The process of forming trays which comprises assembling a plurality of lower surface sheets, a plurality of top surface sheets and a plurality of filler sheets having a smaller area than the surface sheets, forcing the assembly into a mold of such a shape.
that the margin of the surface to the filler sheets and then consolidating the mass under t e influence of heat and pressure into acomposite article.
;3. The process of forming comprises assembling a plurality of surface sheets and a plurality of filler sheets having lessarea than the surface-sheets, bending the margin of the surface sheets upwardly at an angle to the filler sheets and simultaneously exerting pressure on the filler sheets and main portion of the surface sheets and upon the upwardly extending margin of the surface sheets to consolidate the material into a composite article. e
4. The process of forming molded articles which comprises assembling-a plurality of filler sheets upon one or more surface sheets,
folding the margin of the surface sheets upwardly at an angle to the filler sheet and applying pressure against the assembled structure to consolidate it into a compositearticle. v a
5. The process of forming trays which comprises placing a plurality of filler sheets upon surface sheets havinga greater surface 1 area than thefiller sheets, foldin the margins of the surface sheets upward y to form a bottom, an angular disposed portion and a substantially fiat upper edge and then applyin suflicient ressure upon the various parts binding agent and one or more inserts, folding the margin of the surfacesheets at an angle to the filler sheets, and consolidating influence of heat and pressure the assembled and formed sheets under the trays which 7. The process of forming trays which comprises assembling a plurality of uppersurface sheets, a plurality of lower surface sheets, and interposing a pluralit of filler sheets having less area than the sur ace sheets between the lower and upper surface sheets, all of said sheets being impregnated with a binder capable of being hardened under heat and pressure, folding the margin of the sur- I face sheets upwardly, thereby forming angularly disposed walls and a substantially flat edge, and then simultaneously applying heat and sufficient pressure to the bottom, the angularly disposed walls and the upper. edge to force the material at the edge outwardly to form a peripheral flange and to consolidate the material into a composite article. I
8. The process of forming trays which comprises impregnatinga plurality of upper surface sheets and a plurality of lower surface sheets with a "comparatively large amount of a binding agent capable of being hardened under the influence of heat and pressure and a'plurality of filler sheets impregnated with a less quantity of the binding agent than the surface sheets, bending the margins of the surface sheets at an angle to the filler sheets and then applying pressure against the'bottom and angularlyextending side walls to form a rigid, composite article.
- 9. The process of forming trays whichcomprises impregnatingl a plurality of sheets of fibrous material wit a'binder capable of being hardened under the influence of heat and pressure, rounding the edges of the sheets, cutting out notches, thereby forming strips at the corners, folding the marginof the sheets upward at an angle to the main body portion, thereby causing the strips to abut against each other, assembling a plurality of such sheets, and then simultaneously applying pressure against the bottom portion and the angularly disposed margin to form a composite article;
10. The process of' forming trays which comprises impregnating a plurality of sheets of fibrous m'aterlal with a binder capable of being hardened under the influence of heat and pressure, rounding the corners of the sheets, cutting notches out of the corners to forms'tr'ips, assembling a plurality of such sheets and bending the margin upwardly,
thereby causing the strips to abut against each other and form a substantially leveled e, and simultaneously applying heat and 'su cient pressure tothe main portion of the sheets, the angularly extending portion and the edge portion to form a compositearticle having a bottom, upwardly inclined side walls and an outwardly projecting peripheral flange.
11. The process of forming trays which" I comprises impregnating a plurality of sheets of fibrous material with a binder capable of being hardened under the influence of heat and pressure, rounding the corner portions, cutting slits in the corners to form strips, bending the margin of the sheets at'an angl to the main body portion and overlappin the strips formed at the corner, assembling a plurality of such sheets and applying heat and pressure to the bottom and the angularly bent portion to form a composite articles 10 12. The process of forming trays'which comprisesimpregnating a plurality of sheets of fibrous material with a binder capable of being hardened under the influence ofheat and pressure, rounding the cornersof the sheets, cutting slots therein to form a plurality of strips, assembling a plurality of such sheets, bending the margin upwardly at an angle to the body and overlapping the strips at the corners to form a substantially level edge, then applying suflicient ressure to the bottom portion, the angularly d portion and the upper edge to force the material in the edge outwardly'and to form a composite article having a bottom, an angularly disposed wall and an outwardly ex-' tending peripheral flange. r
In testimony whereof, I have hereunto subscribed my name this 14th day of May, 1928.
so NOBLE s. CLAY.-