US2486760A - Method of packaging - Google Patents

Description

Nov. 1, 1949 F. B. PFEIFFER METHOD OF PACKAGING ZSfieets-Sheet 1 Original Filed Feb. 28, 1938 INVENTOR [9:0 8. p/i/FFEZ WI ATTORNEY! F. B. PFEIFFER METHOD OF PACKAGING Nov. 1, 1949 Original Filed Feb. 28, 1938 4 $2 Pea-swee- INVENTOR Fae-a 5f Fi/FFEE.

ATTORNE'. 5

Patented Nov. 1, 1949 METlIOD or PACKAGING Fred B. Pfeifl'er, Akron, Ohio, assignor of one-half to Jesse B. Crossan Original application February 28, 1938, Serial No. 193,214. Divided and this application April 27, 1946, Serial No. 665,518

11 Claims. (cl. 1s -'5s) This invention relates to methods of covering or wrapping objects with sheet materials. In this specification and in the appended claims, the words cover, covering, wrapping" and the like are used in abroad sense to refer not only to packaging operations wherein a sheet material is wrapped completely around an object, but also to other arts and operations wherein a sheet material forms a part of or is associated with only part of a complete article.

In wrapping or packaging articles of commerce prior to this invention, it has been customary to employ substantially non-stretchable materials such as paper, fabric, foil, and cellulose film known commercially as cellophane. Such materials are cut or otherwise provided in blank size and shape of area greater than the surface area of the particular article to be wrapped or covered. Sufiicient excess material must always be used to enable the edge portions thereof to be relatively lapped.

As is well known,"when non-stretchable wrapping material is used to cover a curved surface, it becomes wrinkled as the necessary crowding of the wrapping material takes place. ample of such wrinkling may be seen in the commercial use of holland cloth or the cellulose film known commercially as cellophane to cover the cemented or tacky side of a blow-out patch used as an automobile tire accessory. Another example of the wrapper and also of the excess of wrapping material over the area to be wrapped One exor a rubber hydrochloride film) being manufactured by the Goodyear Tire 8; Rubber Company of Akron, Ohio, and sold commercially under the name ,Pliofilm. This material is characterized by its extreme flexibility and slight stretchability under normal conditions and by its resistance to moisture penetration. I have discovered that I can stretch this material very extensively when it is heated to within certain temperature ranges without injuring or otherwise detracting from either its appearance or its other properties. .I take advantage of this discovery in practicing my invention by causing the film or sheet, while heated, to conform to the shape and size of article being wrapped, and preferably I stretch or expand the film or sheet very considerably in some instances whereby to effect substantial savings in material as well as to enhence the appearance of the wrapping and to when non-stretchable material is used to wrap An important feature of the invention in its broad aspect is to provide a novel method for wrappingor covering in whole or in part various articles with a minimum of material and with freedom from wrinkles and the like.

'More specifically, the invention contemplates the use of a film or sheet of heat-stretchable and heat-scalable material, one type of which is disclosed, for example, in the Calvert Patent No. 1,989,632, such material (a rubberhydrohalide make possible the neat wrapping of any object regardless of its shape. The sheet may be heated over its entire area or over any desired portion of its area dependent upon the requirements of a particular wrapping operation. Y

By way of example, but without limitation, it is here pointed out that the invention may be employed in the wrapping or covering of fruits, vegerial may be applied to the face of a suitable cavitied mold and there held .by its edges. Then by the application of heat in any desired manner,

the material may be softened and caused to ,as--

diifers from the other embodiment hereindisclosed.

Another practice of the invention contemplates a. complete enclosure of the object by convert-' ing two substantially flat blanks by stretching into complementary cover sections approxiw has been opened;

mating the shape of the object and then placing the two cover sections over the object and sealing them together as one. Thus, the two blanks may be anchored in an'air-tight manner around the perimeters of two complementary unheated mold cavities approximating the shape of the object and then, after they have been heated to impart to them the requisite stretchable and scalable properties, stretched into the mold cavities by vacuum and shaped accordingly. The object may then be placed in the mold cavities and the latter, with the vacuum still maintained, brought together into mating relation to'seal the two stretch-shaped blanks together around the object as a complete unitary cover.

In the accompanying drawings:

Fig. 1 is an elevation of an umbrella embodying the invention;

Fig. 2 shows a sheet of rubber hydrochloride or other suitable material placed in hoops after the fashion of the ordinary practice in embroidery work;

Fig. 3 is'a forming mold shown in operative position-while heat is being applied to the rubber hydrochloride and before the vacuum line is open the dotted line'therein indicating the position of the rubber hydrochloride after the vacuum line Fig. 4 is a convex storage form for the umbrella covers invention;

Fig. 10 is a similar view illustrating a difierent step inthe method; and r Fig. 11 is an enlarged fragmentary sectional view on line I I-I I of Fig. 10.

Reference will first be made to Figs. 1 to 8, which illustrate the manner in which a cover for an umbrella, parasol or the like may be made and applied.

Asshown in Fig. 1, the invention contemplates a cover of rubber hydrochloride 209 secured upon an umbrella frame of any ordinary or preferred construction, the one illustrated comprising radial ribs 2I0- connected by adjustable links 2 to a central seam 2I2, and it may be provided with any desired form of handle 2I3 and with a protecting tip of any preferred construction.

In practicing this form of my invention a sheet of appropriate material such as rubber hydrochloride 209 approximately .0015" thick and of proper area, (after being heat treated and stretched) for the umbrella to be covered is,

fastened between an outerhoop 2 I5 and an inner hoop 2 l Binthe usual manner employed in putting goods in embroidery hoops. The outer hoop 2I5 is preferably of aluminum and the inner hoop 2 I 5 may be of wood, rubber or any material that facilitates the assembly of the hoops. The outer hoop 2I5 extends some distance above the inner hoop for reasons disclosed hereinafter.

After the sheet 209 has been placed in said hoops, the hoops are placed on the ledge 2" of the mold 2I8. The inside diameter of the hoop 2; is such that a substantially air-tight flt between the surfaces 2I9 of the mold and 220 of the hoop is effected. The top of the hoop 2I0 becomes in effect the upper rim of the mold 2I8, and it will be seen that the top' of hoop 2I5-extends above the top of the hoop 2 I 0.

The concave shape of the inside of mold 219 is designed with a curvature substantially of that of the umbrella surface to be covered and the mold 2! is provided with a platen 22I which is hingedly connected in any usual manner to the mold as at 222, the platen being provided with a counter-balance weight 229 to facilitate raising the platen to open positionso that the molded umbrella cover may be removed from the mold and another to-be molded may be placed. The platen 22! is provided with a steam chamber 224 being supplied with steam through inlet and outlet pipes not shown but installed by any standard method recognized by steam fitters. The function of the platen is to heat the sheet of rubber hydrochloride and it is to be understood that the heat may be applied from electrical units, hot air or. otherwise. However, it has been found that in this particular form of the invention the best results are obtained by heating the rubber hydrochloride by radiated heat from a platen as shown, the surface of the platen being spaced apart from the rubber hydrochloride 209 approximately when the mold is closed. It will be observed, as shown in Fig. 3, that the hoop 2I5 is designed to hold the plate 22! the desired distance from the blank or sheet 209. Rubber hydrochloride is extensible to a restricted degree in normal atmospheric temperatures but not sufficiently extensible at such temperature to mold to the degree necessary for my purpose. It has been found, however, that as the temperature of the rubber hydrochloride is raised it becomes more extensible until, at approximately 250 F., it will be extensible enough for my purpose. I permit the platen 22! to remain in position shown in Fig. 3 until the temperature of the rubber hydrochloride is raised to approximately 250 F. and then open a valve (not shown) in any ordinary vacuum line 224 which extends from the chamber 225, the chamber being formed by the inside surface of the mold and the sheet 209. The partial vacuum formed in this chamber causes the sheet 209 to be pressed down to the bottom of mold 2I0, the space between the .sheet 209 and the platen 22I purposely being open to the atmosphere by avoiding too snug a fit between the hoop 2I5 and the platen 22I or, if found desirable, by cutting grooves across the top surface of hoop 2I5.

To prevent the sheet 209 from being drawn into the vacuum line a screen 226 is placed over vacuum line opening. Around the edge of the screen 226 is a boss 22'! the purpose of which will be described hereinafter. After the sheet is' thus shaped, it is chilled or cooled, for which purpose the mold 2I8 is supported in a shell 228 in such manner as to provide the water chamber 229,

cool water entering the chamber through inlet 230 and discharging through outlet 23I.

After the sheet 209 has been shaped against the inside surface of the mold 2I8, the platen 22I is raised out of the way of the operator and the operator, by means of hand roller 232, presses the sheet 209 against the boss 22! which results in scoring the sheet sufficiently to locate the center for application of the cover to the umbrella frame. The molded cover 209 is then removed together with the hoops 2I5 and H6. Next the hoops are broken apart and the cover 209 freed shaman therefrom. I have provided a form 233 on which to store the molded covers .as shown in Fig. 4.

The form is convex and of a curvature to corre- 'spond with the concave shape of the mold 2l8.

One or more'covers may bestored thereon and separators may be used if desired. The use of this storage form permits the removal of the molded cover from its mold while the'cover is still warm thereby increasing the capacity for production of scribed except this latter method makes possible the turning inwardly of the edge of the cover 209 this being made possible by turning the edge of the cover away from the mold as shown in Fig. 7 rather than downwardly as is the case shown in Fig. 3. This latter method is practiced by placing the sheet 209 between outer hoop 2 and inner hoop 242 then placing the assembled hoops and cover in molding position on mold 243 and proceed as described in the case of the former method set out hereinabove. After the cover has been molded as shown in-Fig. 8, its edges may be conveniently turned inwardly in asembly with an umbrella frame.

The edges of the cover may be re-enforced in any manner'found desirable such as doubling the edges back on itself or adding reenforcement. Suitable tips of any practical type may be added to the outer ends of the radial ribs or other details of construction added after which the operator places the molded cover 209' in the working form 231 wherein it may be assembled with the umbrella frame.

Reference will now be made to Figs. 9 to 11, which illustrate the manner in which an orange or similar article may be completely enclosed in a unitary cover. As will be observed, two tubular cooperating members, 500 and m have secured in their open cooperating ends fine mesh screens, 502 and 503, in approximately the shape of the object to be covered. At the closed ends of said members 500 and 50! are ports 5 and 505, said ports communicating with pressure and vacuum tanks by means of three- way valves 506 and 501. Blanks of covering material, 5") and 5| l, of the type or nature previously mentioned, or any other suitable material, are applied over the faces of members 500 and 5! which are formed with depressions, 5H and 5H aligned with a vacuum tube, SIG, which is suspended between the open faces of members 500 and 5M, and extends only slightly beyond the edges of the said members. A heating element, Sit, is adapted to be 'moved in between the blanks, 5H! and BI i, to heat said blanks and then to be removed, and the members, Silliand 50 i, are'adapted to be moved toward each other until they contact. The vacuum line thru valves 501 and 509 is designed to create a vacuum within the members 500 and 50 l and the pressure line thru said valves is designed to build up presthis form of the invention is as follows: The

opened causing the blanks to be drawn back 1 against the'screens forming receiving cavities for the article to be covered. Next, the article to be covered is placed between the cavities and the members Ill and "I are moved toward each other, which movement catches the article within the cavities and the movement is continued until the edges of the members 500 and 501, with the cover material between them, contact, which results in sealing or fusing the two blanks together except over the vacuum tube Sit, and this tube extends into the space between the covered article and the cover. The vacuum line BIB is in operation as the cover blanks come together and thereby extract the air from between the cover and the covered object. Next, the small tube 518 is withdrawn and the small hole it leaves may be closedand sealed in any desired manner. Next, the pressure valve is opened and the memhers I and 50! are moved away from each other until the covered article is ejected, the pressure pressing the covering material firmly against the object being covered. To facilitate the removal of the article from the members 500 and 5M; the clamping rings 512 and H3 may be disengaged from the turned edge portions of the blanks Elli and 5 of covering material are placed in position over the open ends of members 500 and 5M, where they are held by the rings SH and 5I3 provided for that purpose. With the 'members 500 and 50! slightly spaced apart as blanks ill and SI I which are now sealed together around the object. In the illustrated embodiment just described, the object is spherical, as an orange, but the invention is not limited in this respect since other objects and other shapes may be operated upon with equal success.

.From the foregoing it will be evident that I have provided novel method steps and apparatus for covering various articles in whole or in part. In practicing the invention, the covering material is stretched, effecting economy and resulting in improved appearance, free from wrinkles. The invention is susceptible of numerous modifications other than those specifically described and illustrated, and the right is herein reserved to make such changes as fall within the scope of the appended claims without departing from the spirit of the invention. YThis application is a true division from application Serial No. 93,214, filed February 28, 1938.

Having thus described my invention, what I claim is: a

-l. A method of covering an object in a film composed of material which when unheated is substantially inelastic but which when heated becomes highly elastic, including the steps of heating the film to render it suiliciently elastic, stretching the film while still elastic toconform it to-the shape of the object to be covered independently of the object, and then while the film isstill elastic applying it in stretched condition to the object and securing it thereon in such elastic stretched condition.

A method of covering an object in a film composed of material which when unheated is substantially inelastic but which when heated becomes highly elastic, including the steps of heating the fllmto render it sufiiciently elastic, then after discontinuing the application of heat but while the film is still elastic stretching the film to conform it to the shape of the object independently of the object, and then while the film to the object and securing it thereon in such is still elastic applying it in stretched condition the steps of providing a blank of heat-stretchable sheet material, anchoring the blank around the perimeter of an individual water-cooled mold cavity approximating the shape of the object to be covered, heating the blank independently of the molds to render it suiilciently stretchable, stretching the heated blank into the water-cooled mold cavity independently of the object, and then, after allowing the blank to cool and become set in its stretch-shaped condition, removing it from the mold cavity and attac 1 to the object.

5. A method of wrapping an object in one continuous operation, including the steps of providing twoblanks of heat-stretchable and heatsealable sheet material, anchoring said blanks around the perimeters of the two unheated molds having complementary cavities approximating the shape. of the object to be wrapped, heating the blanks concurrently independently of the molds to impart to them the requisite stretchable and scalable properties, then while the blanks still retain their heat stretchable property stretching them concurrently into the unheated mold cavities independently of the object, and thereafter while the blanks still retain their heat scalable property'bringing. the unheated mold cavities into mating relation to seal the stretchshaped blanks together around the object as a unitary cover therefor.

6. A method of wrapping an object in one continuous Operation, including the steps of providing two blanks of heat-stretchable and heatsealable material,- anchoring said blanks in an air-tight manner around the perimeters of two unheated molds having complementary cavities approximating the shape of the object to be wrapped, heating the blanks concurrently independently of the molds to impart to them the requisite stretchable and scalable properties, then while the blanks still retain their heat stretchable property creating a vacuum concurrently within the two mold cavities to stretch the blanks into the same and shape them accordingly, next placing the object to be wrapped within the mold I cavities while maintaining the vacuum therein,

and thereafter while the blanks still retain their heat sealable property bringing the mold cavities together into mating relation to seal the stretchshaped blanks together around the object as a unitary cover therefor.

7. A method according to claim 6, including the additional steps of discontinuing the vacuum in the mold cavities after the stretch-shaped blanks have been sealed around the object as a unitary cover and introducing air under pressure into said cavities to press the cover into intimate contact with the enclosed object.

8. A method of wrapping an object in one continuous operation, including the steps of providing two substantially flat blanks of heat-stretchable and heat-scalable sheet material, heating said blanks concurrently to impart-Ito them the requisite stretchable and scalable properties, then after discontinuing the application ofheat to the blanks but while they still retain their heat stretchable property converting them concurrently by stretching into complementary cover sections approximating the shape of the object to be wrapped independently ofthe object, and

thereafter while the blanks still retain their heat scalable property sealing them together around the object as a unitary cover.

9. A method according to claim 8 including the additional step of evacuating air trapped between the object and the cover before completing the sealing of the two cover sections.

10. A method of wrapping an object in a temporary protective film composed of material which when unheated is substantially inelastic but which when heated becomes highly elastic, including the steps of providing two blanks of such material to make up a complete wrapper which will entirely enclose the object, heating said blanks to render them elastic, stretching the two heated blanks simultaneously to increase their area and conform them to the shape of the object, and while the blanks are still elastic securing them 'in stretch-shaped condition simultaneously about the object to form the complete wrapper.

11. A method of wrapping an object in a temporary protective film composed of raterial which when unheated is substantially inelastic but which when heated becomes highly elastic,

, heat-sealing contact.

, including the steps of providing two blanks of such material to make up a complete wrapper which will entirely enclose the object, heating said blanks to render them elastic, stretching the two heated blanks simultaneously to increase their area and conform them to the shape of the object, and while the blanks are still elastic securing them in stretch-shaped condition simultaneously about the object to form the complete wrapper by bringing portions of the blanks into F'REDB. PFEIFFER.

file of this patent:

UNITED STATES PATENTS Number Name Date 673,982 Hamet May 14, 1901 892,702 Wyman July 7, 1908 1,387,805 Roberts Aug. 16, 1921 1,404,320 Roberts et al. Jan. 24, 1922 1,481,866 Heist Jan. 29, 1924 1,524,449 Myers Jan. 27,1925 1,531,505 Roberts Mar. 31, 1925 1,583,381 Zimmerman May 4, 1926 1,685,392 Beadle Sept. 25, 1928 1,737,874 Busch Dec. 3, 1929 ,856,694 De Correvont May 3, 1932 1,925,509 Staud et a1 Sept. 5, 1933 2,071,300 Gammeter- Feb. 16, 1937 2,127,487 Voit Aug. 16, 1938 2,155,445 Pittenger et al. Apr. 25, 939 2,327,170

Calvert Aug. 17, 1943

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