US2104535A

US2104535A - Method of and process for forming paper cups

Info

Publication number: US2104535A
Application number: US78812A
Authority: US
Inventors: Barbieri Cesare
Original assignee: DIXIE VORTEX CO
Current assignee: DIXIE VORTEX CO; DIXIE-VORTEX Co
Priority date: 1936-05-09
Filing date: 1936-05-09
Publication date: 1938-01-04
Anticipated expiration: 1955-01-04

Description

1938. c. IBARBIERI 5 METHOD OF AND PROCESS FOR FORMING PAPER CUPS Filed May 9, 1936 Jan.

f Eg

ME 713 M dye/Ea.

Patented Jail. 4, 1938 UNITED s'rArl-zs METHOD or AND rnocass FOB some 3 runs curs Cesare-Bottled, New York, N. Y., asslznor to Dixie-Vortex Company, Chicago, IlL, a corporation of Delaware Application liday e, was. Serial No. 78,812

7 Claims.

invention relates to improvements in a method of and process tor forming paper cups of the type coonly used as paper drinking cups, ice cream cups,'ancl for similar purposes, 7

@ although the invention will have other uses and purposes as will be apparent to one skilled in the art.

in the manufacture of paper couteiners, it is desirable to produce the containers as economiw cally as possible, without detracting from their strength and emcie ocy. It is also desirable to give a resultant container an attractive appeeronce and render the some extremely cosy and natural to henolle.

15 With the foregoing in mind, it is en object of the present invention to provide o. method of and process for forming a paper container which may he in. the form or o. poper drinking or frozen confection cup mode of a thermoplastic treeted paper, the finished cohteiuer having e formed mouth portion stifiened eud'held in shape by moons of the thermoplastic with which the pa.- per has -oeeh treated.

The invention else provides a novel method of making a paper container and forming the some into e desired shape in an economical manner.

Another object of the invention is the provision of a method or process oi forming o container made of o thermoplastic treated paper, including the application and removal of heat sufioieut to melt or soiteu the thermoplastic of the paper, the forming operation occurring during the up piicotion oi heat.

Still another object or the invention is the provision of a process of forming a container made or s, thermoplastic treoted paper, including the steps of melting or softening the thermoplastic, shaping the paper of the container, and freezing or permitting the thermoplastic to set with the paper in its she term. i i

A further object of the invention is the provision of a method or process for blunting the apex oi as paper container having substantially a'truly conical shape.

A further feature of the invention, is the provision of a. method or process for blunting the apex of a conical paper container in which the 'paper used is treated with a thermoplastic, the

method including the steps of softening the thermoplastic, shaping the apex, and either freezing or permitting the thermoplastic to harden with the apex in its shaped form. This invention also contemplates contemporaneously shaping dlflerent parts or. a container made of thermoplastic treated paper by soften-- ing the thermoplastic, and relying upon the subsequent setting the thermoplastic to hold the paper in its desired shape.

The invention in general consists in initiolly forming a container into general shape from one or more pieces of a paper treated with a thermoplastlc, A heated shaping tool is next applied to the port ofthe container to be shaped, the epplicction of the tool resulting both in c melting or softening of the thermoplastic carried hr the paper and a shaping of the particular part of the container to which the tool is applied. Upon removal of the tool, the surrounding air is of suliicient coolness to almost immediately set or rigidify the thermoplastic which will then greatly old in strengthening and maintaining the shoped part of the paper, although, if desired, the poper may be chilled sufllclently to quickly freeze or set the thermoplastic. This chilling operation could be accomplished, by way of examplerhv' blowing a blast of cold air over the formed poser.

Difierent parts of the container may he she.

in this manner, either simultaneously, contend porsneously or successively, as may be deemed most desirable.

As stated above, the invention contemplates the shaping of difierent ports of the container, such as the flaring of the rim or mergih crowd the mouth of the container, the he or the margin around the container, the bluntiop oi the apex in a. conical container, and slmiisr operations. The invention is, of course, applicable to containers of both the couicol and fiat-hottom type, insofar as the shape of the contoiuer permits application of the invention.

While some 01 the more salient features, chor acteristics, and advantages of the present inveution have been above pointed out, others will hecome apparent from the folowing disclosures, l0 taken in conjunction with the eccompenyiug drawing, in which: 1

Figure l is a fragmentary part scctio, part elevational view, illustrating an initial step in the forming of the container, and somewhat diagrammatically showing apparatus used.

Figure 2 1s a view oi. the samenature as Figure 1 but showing a more advanced step in the making of the container.

Figure 3 is a plan view of the flnished'contamer. V

Figure 4 is a side elevationalvlew or the finished container.

Figure 5 is a fragmentary sectional view, illuag5 t'rating the forming of a different shape to a part 'of the container.

As shown on the drawing:

By way of example and for the purpose of clarity, I have illustrated a container generally conical in shape, and certain steps in the process of making such a container. The container is preferably made from a single blank of paper or equivalent material. The material used is initially treated with a thermoplastic, such as a suitable wax, resin or gum.

Of course, there are several ways of treating the paper or similar material with a thermoplastic. One of these ways resides in dipping the material in a melted or softened thermoplastic, either before or after forming the material into container shape, and thus coating the material with the thermoplastic. 1

Another satisfactory way, and the preferable way, is to impregnate the material with a thermoplastic to produce what is commonly termed a dry-wax paper, one in which the thermoplastic is not clearly evident from an examination of the outer surface of the material, and in which little or no thermoplastic will be presented as a result of scraping the material with a sharp in-- strument.

For the purpose of clarity, I have illustrated the present invention and will hereinafter describe the same in connection with the forming of a container of the impregnated or dry-wax paper.

A blank of paper is first out and then formed into general container shape by means of any suitable cup-making machinery, that illustrated being a satisfactory example. 'In this instance, the forming of the blank provides a, container 6 of substantially true conical shape, the container illustrated having overlapped marginal portions, as indicated at 1, held together by any suitable adhesive.

In the illustrated embodiment, the container 6 is shown as having been formed on a suitable mandrel 6 carried by a shaft 9 and provided with a blunted or recessed apex l0. As seen clearly in Figure 1, the container initially extends beyond the blunted end of the mandrel i and terminates in a relatively sharp apex II.

The mechanism, as seen in Figures 1 and 2, also includes a tool l2 movable longitudinally relatively to the shaft 9 and having an annular groove l3 in the front face thereof of such a shape as to outwardly flare the adjacent margin of the container when the tool is pressed thereagainst. The tool I2 is also internally provided with a heating element, preferably an electrical heating element, indicated in general by numeral l4, energized by a pair of wires [5 which may be connected to any suitable source of, electrical energy. This heating element i4 is sufflcient to raise the temperature of the tool l2 to such a degree that contact of the tool with the container. 6 will meltthe thermoplastic carried by the container paper.

The mechanism further includes a forming element for blunting the apex of the container, this element being generally indicated by numeral IS. The blunting apparatus may include a cup-shaped member I! carried by a shaft Hi, the shaft being centrally drilled to accommodate a pin is keyed to the shaft. A hollow plunger 20 is slidable within the member I! and the hollow therein is of a proper size to receive the pin IS. The plunger is shouldered as at 2| to keep a coil spring 22 within the socket of the member H, which coil spring constantly urges the plunger outwardly. The pin I9 is prov vided with an elongated slot 23 through which a pin 24 anchored in the shank of the plunger extends to limit the in and out movement of the plunger. The plunger is provided at its forward end with an opening 25 substantially of the shape of a truncated cone to receive the apex of the cup 6, and the forward end of the pin is is provided with an arcuate recess 26 which, when applied, will cause a swaging and rounding of the apex ll. Of course, any desirable shaping of the apex may be provided by properly shaping theopening 25 and the forward end of the pin 59.

The cup-shaped member W is also provided with a heating element, preferably an electrical heating element, 27, from which a pair of conductors 28 may extend to any suitable source of electrical energy. This heating element is sufiicient to raise the temperature both of the plunger 2% and the forward end of the pin [9 to a degree that will cause a softening or melting of the thermoplastic carried by the paper.

In carrying out the method of this invention, as stated above, a blank of paper is first formed into the substantially truly conical shape seen in Figure 1. It is next desired to outwardly flare the margin of the container around the mouth thereof, and to round or blunt the apex thereof. These operations may be performed simultaneously, contemporaneously or successively, as may be most desirable. The tool I2 is moved relatively to the shaft 9 until the inner portion of the groove is contacts the margin of the container. Further movement of the tool l2 results in a shaping of the container margin into an outward flare 29, as seen best in Figure 4. Of course, such contact of a cold shaping tool would result in a deformation of the margin of the container in the nature of a flare, but the flare so provided, especially in relation to a relatively light-weight stock, would not be permanent or rigid to the desired extent. In other words, a flare so provided might be distorted in removing a cup from a dispenser or in other ways.

However, in the present instance, the application of a heated tool results in a softening or melting of the thermoplastic carried by the paper will be held in a substantially permanent and rigid condition, insofar as the particular paper or material permits, by the set thermoplastic.

Preferably, the application and removal of the tool isa very rapid action, and the thermoplastic will set almost instantaneously upon removal of the tool. In such application, the tool 12 may be spinning relatively to the container 6, the container spinning relatively to the tool, or both stationary or spinning, as may be deemed most desirable.

In similar manner, the apex blunting mecha nism is brought into play against the apex of the cup with suflicient pressure to move the plunger rearwardly to the position seen in Figure 2, causing the apex to be blunted,.in this instance rounded, bythe end of the pin IS. The heat of this mechanism also causes a melting or softening of the thermoplastic which almost instantaneously sets or hardens upon removal of the tool. As

may be provided upon the removal of the tool, it such is deemed necessary. These operations produce a novel form of container, such as is seen in Figures 3 and 4, namely, a substantially conical container with a flared mouth 29 and a rounded apex 30.

It will be noted that the same flaring process may be used upon a container which does not have an apex, and the invention further is not limited to performing these specific operations, but certain parts of the container may be shaped as desired by the practice of this invention, the illustrated operation being sumcient for the purpose of setting forth the invention in an adequate manner.

In Figure 5, I have shown how the mouth margin of a container 60. may be provided with a bead ii. In this instance, the container is carried on the same mandrel 8, but a tool He is used having a substantially semi-circular groove thereinoi a proper shape to provide a bead II. This tool I 20. is heated in the same manner as the previously described tool i2 and functions in substantially the same way.

From the foregoing, it is apparent that I have provided a novel method and process for forming a container out of paper or similar material, the method and process being highly emcient and rapid in operation, and very economical to practice.

I am aware that many changes may be made and numerous details of construction may be varied through a wide range without departing from the principles of this invention, and I, therefore, do not purpose limiting the patent granted hereon otherwise than is necessitated by the prior art.

I claim as my invention: 4

1. The method of forming a container of thermoplastic treated paper, including forming a blank of said paper into a container having substantially the shape of a true cone, contemporaneously applying heat to the mouth edge of the container and also to the apex thereof, shaping these parts, and removing the'heat permittingthe thermoplastic to set and maintain the new shapes of the mouth edge and apex.

2. The method of blunting the apex of a conical container made of thermoplastic-treated material, including applying a heated shaping tool to the apex of the container and relatively quickly removing it therefrom.

3. The method of blunting the apex of a conical container made of thermoplastic-treated material, including heating the apex to soften the thermoplastic, shaping the apex, and permitting the thermoplastic to set.

4. The method of making a container, including forming a container of substantially true conical shape from a blank of material carrying a thermoplastic, and then reshaping the very point of the conical container to eliminate sharp ness by simultaneously applying both heat and pressure to said point, the heat being sufl'icient to melt the thermoplastic carried by the material.

5. The method of making a container, including forming a container of substantially true conical shape from a blank of material carrying a thermoplastic, and then reshaping the very point of the conical container to eliminate sharpness by simultaneously applying both heat and pressure to said point. the heat being sufilcient to melt the thermoplastic carried by the material, removing the heat and pressure, and applying a cooling medium to the reshaped point to chill the thermoplastic.

6. The method of making a container, including forming a container of substantially true conical shape from a blank of paper carrying a thermoplastic, reshaping the very apex of the container to eliminate sharpness, temporarily melting the thermoplastic during the reshaping of the apex. and permitting the thermoplastic to reset with the apex in its new shape.

7. The method of making a paper cup ofconical formation which consists in iii-st forming the cup with a relatively sharp tip at its apex and thereafter subjecting said tip to endwise pressure to render the same blunt. as well as ironing the blunt tip to give it a smooth set.

CEBARE BARBIERI.