US2037631A

US2037631A - Method of wrapping an article

Info

Publication number: US2037631A
Application number: US616082A
Authority: US
Inventors: Oscar H Hultin
Original assignee: Pneumatic Scale Corp
Current assignee: Pneumatic Scale Corp
Priority date: 1932-06-08
Filing date: 1932-06-08
Publication date: 1936-04-14
Anticipated expiration: 1953-04-14

Description

April 1936- o. H. HULTIN 2,037,631

METHOD OF WRAPPING AN ARTICLE Filed June 8, 1932 2 Sheets-Sheet l INVENTOR U iv. Mm.

(0M 3mm ATTORNEY April 14, O H HULTlN 2,037,631

METHOD OF WRAPPING AN ARTICLE Filed June 8, 1932 2 Sheets-Sheet 2 o @MM ATTORNEY Patented Apr. 14, 1936 UNITED STATES PATENT OFFICE 2,037,631 METHOD OF WRAPPING AN ARTICLE Application June 8, 1932, Serial No. 616,082

8 Claims.

This invention relates to a method of wrapping an article.

In general the invention has for an object to provide a novel method of producing a novel and superior wrapped article characterized by having the wrapper shrunk drum-tight thereon.

The invention has for a further object to provide a. novel method of producing a novel and superior wrapped package having a wrapper comprising transparent regenerated cellulose and in which the wrapper is wrapped upon the package in drum-tight relation to provide the package with a transparent wrinkleless appearance by which printing or lithographing upon the surface of the package is accentuated and caused to stand out in relief by reason of the gloss of the drum-tight wrapper to thereby impart a stronger, more pleasing, and more commercially valuable wrapped package.

In the drawings illustrating the preferred apparatus for practicing the present invention, Fig. l is a side elevation of a sufiicient portion of a wrapping machine to enable the invention to be understood; Fig. 2 is a side elevation of the same; Fig. 3 is a perspective illustrating the improved wrapped article; Fig. 4 is a detail in elevation viewed in the direction of the arrow 4 of Fig. 2; and Figs. 5 and 6 are views in side and end elevation of a sufilcient portion of a modified form of wrapping machine to enable the invention to be understood.

In the art of wrapping various commercial articles experience has shown that with the various forms of wrapping machines now in use, definite limits exist in the degree of tightness with which a wrapper can be wrapped about an article. I have found that a superior wrapped article may be produced by utilizing as a wrapper a material capable of being shrunk, and then wrapping the article and subjecting the wrapper to treatment to shrink the same drum-tight onto the article. As typical of such material, I may mention regenerated cellulose which may be shrunk by the application of heat to an extent of 4 or 5% of its area. Accordingly, the present invention aims to provide a novel method and also novel apparatus for producing the improved wrapped article.

In the packaging industry many attempts have,

for a number of years, been made to produce a satisfactorily wrapped waterproof package. A number of years ago attempts were made to produce as highly a waterproof package as possible by means of a wrapper and the development centered around the use of wax paper for wrapping the packages and the sealing of the end flaps by heat. The purpose of the heat was to melt the wax and thus effect the sealing of the folded end flaps. While this procedure was fairly suc- "cessful as far as solving the problem of producing a waterproof package was concerned, nevertheless inherent properties of the wax wrapper presented difficulties which have detracted to a substantial extent from the value of the waxed wrapped package. During warm weather when the wax became warm, the wax became tacky and collected a maximum amount of dirt, thus detracting from the appearance'of the package, and obscuring the underlying printing and lithographing. Even when freshly wrapped, the deing upon the body of the package to impart sales appeal to the package comprised a major portion of the cost of the completely wrapped package, and when the high-priced lithographed package was wrapped with wax paper most of the effectiveness of the lithographing was destroyed.

Attempts have also been made to coat a package with liquid coating material such as varnish, lacquer, and the like, by dipping and spraying processes for the purpose of providing a highly glossy transparent film over the lithographing or labelling upon the package, but such methods have not been practical for the reason that the varnish and solvents have entered through the corners of the package and between the folded flaps, contaminating the contents of the package by entrance of either the coating material it'- self or by contamination of the contents by the odors from solvents contained therein. Another difficulty which has detracted from the practicability of any dipping processes has resided in the tendency of the corner portions of the coating to break, so that as a result in practice the coating of packages with liquid coating materials has not been put into commercial use.

I am aware that it has been heretofore proposed to wrap articles such as packages of cigarettes in transparent wrappers of regenerated cellulose, but as far as I am aware all of such wrapped packages have been of the type which is known in the packaging industry as loose wrapped" packages. These loose wrapped packages are produced by merely wrapping the wrapperaroundthe package and then folding and sealing the end flaps, and as a result the wrapper does not closely adhere and conform to the surface of the package, and as a matter of fact many portions of the wrapper are spaced an appreciable distance from the underlying surface of the wrapper. The result has been that in these loosewrapped packages in which transparent regenerated cellulose has been used, the wrapper has presented a more or less wrinkled appearance and the wrapper does not snugly adhere to the surface of the package. In addition to the unsightly appearance of the loose wrapped" package as compared to the present wrapped package, the presence of the wrinkles and irregularities in the transparent wrapper produces a series of light-reflecting facets which destroy the visibility of the underlying printing and lithographing upon the surface of the package when the package is viewed from certain angles such that the light reflecting facets are presented in the line of vision. The fact that many portions of the wrapper are spaced substantial distances from the printing and lithographing upon the surface of the package prevents the highly glossy wrapper from accentuating the underlying printing and lithographing, and as a result the commercial appearance of the package is diminished. In the wrapped package produced by the present method, the highly glossy film occupying a position closely adjacent to the printed or lithographed surface of the package produces the effect of a highly glossy varnish film over the surface, causing the printing and lithographing to stand out and be accentuated, and increasing the advertising value of the package.

In accordance with the present method of wrapping, the article, such for example as a package, is first wrapped with a wrapper of a material capable of being shrunk, and preferably with a transparent wrapper of regenerated cellulose. The article may be wrapped by hand or it may and preferably will be wrapped in a machine in which the article such as 'a package is operatively supported by package moving means during the operations of wrapping the wrapper about the package, sealing the side seam, and folding and sealing the end flaps. In the case of a package, after it has been thus wrapped, a wrapped package is produced of the loose wrapped type, and provision is then preferably made in accordance with the present method for effecting the shrinking of the regenerated cellulose wrapper into drum-tight relation onto the package. This is preferably accomplished by means of heat, and to this end the package is subjected to heat preferably accompanied by pressure and a slight rubbing or ironing action by which the regenerated cellulose is caused to contract into drum-tight relation onto the package. It has been found experimentally that the amount of shrinkage at any given temperature varies with different forms of the commercially attainable regenerated cellulose and that in some instances slightly more shrinkage takes place across the grain than with the grain of the regenerated cellulose. By the term grain applicant intends to define the direction in which the regenerated cellulose is most easily torn. However, in all instances sufficient shrinkage may be obtained by the application of a moderate amount of heat such as to cause the wrapper to assume drumtight relation on the package. The effect of the accompanying ironing of the wrapper serves to facilitate the production of a completely smooth, wrinkleless wrapper and to completely expel any air pockets between the wrapper and the underlying package.

Referring now to the drawings, the improved wrapped article ID, such as a package, is illustrated in Fig. 3 in which 20 represents the wrapper of regenerated cellulose shrunk drum-tight onto the article. In Figs. 1 to 4 I have illustrated a suflicient portion of one form of wrapping apparatus embodying the present invention to enable the same to be understood. The

particular type of apparatus illustrated in Figs. 1 to 4 is adapted foroperation with the type of regenerated cellulose which is not self-sealing by heat, and as therein illustrated the regenerated cellulose in sheet form is withdrawn from a supply roll 30 and passed between a pair of glue rolls 32 supplied by a feed roll 33 from a glue pct 34 which is capable of being lifted to replenish the supply of glue upon the roll 33 by the operation of the lever 35. The glue rolls merely apply a narrow strip of glue for the side seam 22 of the package, and after the application of the glue a requisite length of the wrapper is cut off by the shears 36. At this stage in the operation of the machine, the wrapping sheet positioned upon a plurality of feed belts 40 is disposed above an elevator 42 upon which a package is moved by a package pusher 43 from an incoming package supply conveyor 44. The elevator 40 then operates to raise the package and force it with the wrapper into an aligned pocket 48 on an arm 49 of a rotatable spider indicated generally at 50.

The movement of the package upwardly and into the pocket 48 operates to wrap the wrapper about three sides of the package. After the package has been introduced into the pocket 48, a folding member 52 is then operated to fold the narrower side flap against the fourth side of the package, and as the spider 59 is then intermittently rotated to the next station, the remaining side flap is brushed down by the brush 54. At the second station provision is made for applying adhesive to the inner surfaces of the last folded pair of both top and bottom end flaps as the latter project above and below the package preparatory to being folded down, and as illustrated in Fig. 4 this operation is performed by adhesive applying rolls 60 mounted upon members 62 arranged to slide vertically in guides 64 and to pass within the upstanding end flaps to apply adhesive to the inner surfaces of the opposite pair ofend flaps projecting at both the top and bottom of the carton which are folded down last during subsequent folding operations to be referred to.

At each reciprocation of the members 62 an additional supply of adhesive is applied to the roll 60, but from supply rolls 66 fed from any convenient source. In order to support the upstanding end flaps, supporting members 68 are arranged to be moved into a position to support and engage the outside of the end flaps during the passage of the rolls 50 within the end flaps. After the adhesive has thus been applied to the inner surfaces of the end flaps, the spider then moves to the third position where the narrower flaps of both the top and bottom are folded in by folding instrumentalities indicated generally at 16. The spider then moves to the fourth station where the last sets of end flaps are succe'ssively folded thus effecting through the adhesive which has been applied thereto at the second station, as above described, the complete sealing of the end flaps at each end of the package. As thus far described, the machine may and preferably will comprise any usual or preferred form of wrapping machine for performing the described operations now upon the market, the details of construction and mode of operation of which are well-known, and for this reason it is thought that the more or less diagrammatic illustration of the same, together with the above description will sufiice for an understanding of the invention.

The wrapped package produced as above described and after the operation of the folding instrumentalities at the fourth station is what is regarded in the art as a loose wrapped package, and in which as above stated the wrapper is wrapped more or less loosely about the package. Provision is made for subjecting the wrapper of the package to heat and preferably to heat and a rubbing action in order to effect shrinkage of the wrapper of regenerated cellulose into drum-tight relation to the package. As illustrated in Fig. 2, the top and bottom of the package is arranged to pass between a pair of spaced heating plates, one of which is shown at 80, arranged to slidingly engage the top and bottom of the wrapped package as the latter is moved by the spider from the fourth station to the ejecting or sixth station, as shown in Fig. 2. The action of the heat and also the rubbing action produces smooth and contracted ends of the, wrapper which causes the same to shrink in drum-tight relation to the ends of the package. During the ejection of the package from the spider 50 at the sixth station by the usual form of ejecting mechanism indicated generally at 82, successive composite sides of the package are caused to slidingly engage spaced heating plates 84 as the package is slid between the plates. Provision is then made for effecting passage of the package between a second set of heating plates 86 positioned with relation to the plates 84 so that the remaining two composite sides of the package are engaged by the plates. Thereafter the completed package is delivered from the machine on the'outgoing conveyor 90. In order to heat the

plates

80, 84 and 86, any form of heating apparatus may be employed, that herein shown comprising electric heating elements 92. a

From the description thus far it will be apparent that the present apparatus operates to wrap the regenerated cellulose wrapper about the package, seal the end flaps, and thereafter subject all portions of the Wrapper to the action of heating plates to effect shrinkage of the wrapper into drum-tight relation tothe package.

In Figs. 5 and 6 I have illustrated a modified form of apparatus of the general character illustrated in Figs. 1 and 2, with the exception that the apparatus is particularly designed for operation in connection with the wrapping of packages with the commercial forms of regenerated cellulose which are self-sealing by heat, and at the second station I have provided a reciprocatory heating element designed to contact along the side sealing lap and to heat the overlapping portions of the side seam of the wrapper to effect the sealing thereof. In addition at station 4 I have provided a pair of pivoted electric heating elements, as best shown in Fig. 5, which are operated to. engage the end flaps of the wrapped package after the end flaps have been folded down to heat the same and effect the sealing thereof, and at the same time to effect shrinkage of the end portion of the wrapper into drumtight engagement with the ends of the package. The machine illustrated in Figs. 5 and 6 is provided with the mechanism illustrated in Fig. 2

by which the body portion of the wrapper is heated to shrink the same into drum-tight engagement with the package.

As above stated, in both the machines illustrated in Figs. 1. 2, 5 and 6, the instrumentalities for rotating the spider and performing the folding operations, as well as the package moving mechanism, may and preferably will comprise the usual forms now employed in standard wrapping machines now upon the market, and further description thereof is deemed unnecessary.

While the preferred method and preferred form of apparatus has been herein illustrated and described, it will be understood that the invention may be embodied in other forms within the scope of the following claims.

Having thus described the invention, what is claimed is:-

1. The method of wrapping an article, which consists in wrapping the article under the normal atmospheric conditions existing at the time of wrapping, with a wrapper of a material capable of being shrunk below its normal size by heat, and then heating the wrapped article under substantially the same atmospheric conditions to effect the dry shrinking of the wrapper into drum-tight relation onto the article.

2. The method of wrapping an article, which consists in first wrapping an article with a wrapper of water-proof regenerated cellulose, and then dry shrinking the wrapper drum-tight onto the article by the application of heat thereto.

3. The method of wrapping an article, which consists in first wrapping an article under the normal atmospheric conditions existing at the time of wrapping, with a wrapper of transparent regenerated cellulose, and then dry shrinking the wrapper drum-tight onto the article by the application of heat and pressure.

4. The method of wrapping an article, which consists in first Wrapping the article under the normal atmospheric conditions existing at the time of wrapping, with a wrapper of regenerated cellulose, and then dry shrinking and smoothing the wrapper drum-tight onto the article with the application of heat and movable pressure.

5. The method of wrapping a package, which consists in wrapping the package in a wrapper of regenerated cellulose, then passing the package between heating elements for engaging and heating the ends of the wrapped package, and then passing the package between heating elements for engaging successive opposite sides of the body of the package whereby to dry shrink the wrapper drum-tight onto the article by the application of heat.

6. The method of wrapping a package, which consists in first wrapping the package with a wrapper of regenerated cellulose of the character capable of sealing by heat, applying heat to the folded fiaps of the package to effect heat sealing of the same, and to dry shrink the wrapper drumtight onto the ends of the package, then applying heat to the body of the package to shrink the body of the wrapper drum-tight thereon.

7. The method of wrapping a package, which consists in first wrapping the package with a wrapper of regenerated cellulose, and then passing the package between successive sets of heating elements whereby to apply heat to the ends and body of the package to effect the dry shrink ing of the wrapper drum-tight thereon.

8. The method of wrapping a package, which consists in wrapping the package in a wrapper of regenerated cellulose of a character capable of sealing by heat, and then exposing the package to heat to effect the sealing of the folded portions of the wrapper and to dry shrink the entire wrapper drum-tight onto the package.

f OSCAR H. HUL'I'IN.