US2987857A - Method of producing infusion bags - Google Patents

Description

June '13, 1961 J. P. WHELAN METHOD OF PRODUCING INFUSION BAGS 4 Sheets-Sheet 1 Filed Oct. 22, 1958 a4 *Jltii Fig.3

3O Fig 5 Fig. 4

INVENTOR.

James R Whe/an fmwecbwe ATTORNEY June 13, 1961 wHELAN 2,987,857

METHOD OF PRODUCING INFUSION BAGS Filed Oct. 22, 1958 4 Sheets-Sheet 2 "Ilium I l 8 IIlllIIIIIIllllllllllllIllllIlll= IlllllIlllllllllllllllllllll IIIIIIIIIIIIIIIllllllllllll f INVENTOR.

James R Whe/an WWW ATTORNEY June 13, 1961 J. P. WHELAN 7,857

METHOD OF PRODUCING INFUSION BAGS Filed 001'.- 22, 1958 4 Sheets-Sheet 5 I2 4 INVENTOR.

James F. W/ze/an Hg /4 9 BY 92 wtw2fl ATTORNEY June 13, 1961 J. P. WHELAN 2,987,857

METHOD OF PRODUCING INFUSION BAGS Filed Oct. 22, 1958 4 Sheets-Sheet 4 INVENTOR. James R Whe/an Unite States Patent 2,987,857 METHOD OF PRODUCING INFUSION BAGS James P. Whelan, Quincy, Mass., assignor to Pneumatic Scale Corporation, Limited, Quincy, Mass, n corporation of Massachusetts Filed Oct. 22, 1958, Ser. No. 768,916 16 Claims. (CI. 53-14) This invention relates to a method of producing bags and particularly infusion bags, each having a handle comprising a tag and a string attached thereto.

The invention has for an object to provide a novel and improved method of producing bags of the character specified whereby the bags may be rapidly produced in a simple and practical manner.

With this general object in view and such others as may hereinafter appear, the invention consists in the method of producing bags hereinafter described and particularly defined in the claims at the end of this specification.

In the drawings illustrating the preferred embodiment of the invention:

FIG. 1 is a developed plan view of a sheet of bag forming material showing a handle comprising a tag and a string attached thereto;

FIG. 2 is an end view of the assembly shown in FIG. 1 after folding the sheet of bag forming material upon itself;

FIG. 3 is a front view of the completely sealed infusion bag and attached handle;

FIG. 4 is a cross sectional view taken on the line 4-4 of FIG. 3;

FIG. 5 is a similar view of a modified form of infusion FIG. 6 is a perspective view diagrammatically illustrating the successive steps in the preferred method of producing successive filled and sealed bags having handles attached thereto;

FIGS. 7 through 15 are cross sectional views illustrating the successive steps followed in producing the filled and sealed bags provided with handles;

FIG. 16 is an end view showing the filled and scaled bag with its handle extended for use;

FIG. 17 is a perspective view illustrating a modified step in the preferred method of producing the bags wherein the continuous strip may be separated into lengths of a plurality of sections and the mouths of the sections in each length sealed as a unit; and

FIG. 18 illustrates the step of cutting the multiple unit length to provide individual bags.

in general the present invention contemplates a method of making an infusion bag of the type produced by folding a rectangular blank of heat scalable filter paper upon itself and joining the side edges thereof, preferably by a heat sealing operation whereupon a quantity of the infusion material, such as tea, is deposited into the bag and the mouth of the bag is heat sealed. The bag forming material preferably comprises a thin porous filter paper embodying a thermoplastic material which becomes adhesive upon being subjected to heat and pressure to cause adherence of the confronting inner faces of the paper. In practice, one face of the bag forming paper which comprises the inner face of the bag preferably contains more thermoplastic material than the other or outer face of the bag forming paper. In accordance with the present invention a handle comprising an elongated flexible member or string having a tag attached thereto is secured to the bag in a manner such as to afiix one end of the string between the scaled mouth portions of the bag, the other end of the string having the tag attached thereto being wound aboutthe bag and detachably secured in close proximity to the bag whereby to prevent entanglemcnt of the handle with similar bags and handles when packed in a container.

In practice, successive bags provided with handles are preferably produced in accordance with the present method by continuously advancing an elongated web of bag forming material and dctachably securing the handles transversely of the web and in longitudinally spaced relation on the continuously moving web. The web with the attached handles may then be inverted and the web folded along its longitudinal center line to form a folded strip open at the top and with the handles wrapped about the outer faces of the strip. Thereafter the strip is heat sealed transversely at spaced intervals, intermediate the space between successive handles, to provide a strip of connected bag sections which may then be filled and top scaled to produce an elongated strip of filled and sealed bag sections. The strip may then be severed through the transversely sealed areas to produce individual filled bags each having a handle wrapped thereabout. During the application of the handle to the web one end of the handle may be folded under a marginal edge of the web so that upon sealing the mouth portion of the bag sections the folded-under edge of the handle will occur between the walls of the mouth portion and will be scaled thercbetween to connect the string to the bag. In practice, the tag and intermediate portions of the string may be detachably or lightly heat sealed to the bag so that the tag and the string may be subsequently broken away from the bag to extend the handle for use. In a modified method the continuous strip of filled and connected bag sections open at the top may be separated into predetermined lengths each containing a plurality of bag sections which may be heat sealed as a unit to close all of the mouths of the predetermined length of bag sections simultaneously, and the length of bag sections may then be severed as a unit simultaneously through the transversely scaled areas to produce the individual bags.

Referring now to the drawings, and particularly to FIGS. 1-5, the infusion bag produced in accordance with the present invention is herein illustrated as comprising a flat bag 10 formed from a rectangular sheet 12 of heat scalable bag forming material, preferably comprising a thin porous paper sheet or web having thermoplastic material incorporated therein. In the production of the bag the rectangular sheet 12 is folded along a medial line 14 to form two half sections and to present the thermoplastic faces together whereupon the marginal side edges are heat sealed by the application of heat and pressure. A quantity of tea or other infusion material 15 is then introduced into the bag whereupon the mouth of the bag may be heat sealed.

As herein shown, the present infusion bag is provided with. a flexible handle comprising a paper tag 18 and a thin and relatively narrow ribbonlike length of string 16 which may comprise paper, cellophane or the like embodying a thermoplastic material so as to be capable of being heat sealed. One end of the string 16 may be heat sealed, as indicated at 17, to a marginal edge of the paper tag 18 which may comprise heat scalable material or may comprise a non-heat scalable material. The other end of the string 16 may be inserted between the walls of the mouth portion of the bag and secured thereto by heat sealing.

As illustrated in FIGS. 2 and 3, in order to secure the handle in close proximity to the bag, the handle may be wrapped around the bag, as shown, and the opposed marginal edge of the tag 18 may be lightly heat sealed to the bag at a relatively small scaling area as indicated at 20. In practice the upper marginal edge of the tag is preferably disposed in alignment with the upper edge of the bag, and the small sealing area 20 occurs at the twoply sealed mouth portion of the bag, the heat seal being of the tag for a short distance.

string may extend a short distance beyond the opposed 30 effected by virtue of the thermoplastic material in the bag below the lower marginal edge of the tag, and another sealing area indicated at 24 being disposed adjacent the -lower or folded edge of the bag. It will be seen that the --bag and handle thus produced is arranged to maintain the string and the tag in close proximity to the bag so as to avoid entanglement of the handle with similar bags and handles when packed in a container. It will be under- "stood that the lightly sealed areas 20, 22 and 24 comprise frangible sealing areas which may be readily broken by the consumer without damage to the'bag or the handle 1 to extend the handle for use.

Referring now to FIG. 1, in accordance with the preferred method of making an individual infusion bag and handle, the paper tag 18 may be placed on the unfolded rectangular sheet of bag making material 12 with a marginal edge of the tag aligned with a transverse marginal edge of the sheet and disposed substantially medially of the longitudinal edges of the sheet, the tag being subsequently lightly heat sealed to the sheet. A length of heat sealable string 16 may then be placed longitudinally of the sheet in a medial po'sition with one end of the string overlying the opposed or inner marginal edge The other end of the transverse marginal edge of the sheet, the extended portion being indicated at 26. With the tag lightly heat sealed to the sheet, and the string thus positioned relative to the rectangular sheet of bag forming material, the heat sealing operation may be performed: to heat seal one end of the string to the tag as indicated at 17; to lightly heat seal the other end of the string to the transverse marginal edge of the sheet as indicated at 28; and to lightly heat seal the string to the body of the sheet at selected areas as indicated at 22, 24. Thereafter the assembled sheet and handle may be folded along the medial line 14, and the side edges 30, 32 may be heat sealed. The infusion material may then be deposited into .the bag, and after the extended end 26 of the string is folded inwardly over the adjacent edge of the sheet, the mouth portion 34 may be heat sealed to seal the extended end 26 between the walls of the mouth portion and to complete formation of the bag and handle. It will be obvious that the step of folding the sheet and handle in their preassembled form eifects wrapping of the handle about the bag as illustrated. In practice the extended portion 26 of the string may be turned under and heat .sealed to the underside of the sheet prior to folding the assembled sheet and handle as described. It will also be observed that the outer portion of the string indicated at 28 occurs at the mouth portion to become tightly heat sealed thereto during the mouth sealing operation. Thus, when the handle is extended, as shown in FIG. 16, by detaching the handle at the lightly sealed areas, the bag end of the string will extend from the outer face of the mouth po'rtion as shown. The upper edge of the tag, which is also included in the mouth sealing area, may

be easily broken away since in practice the fibers on the outer face of the bag forming material contain less thermoplastic material than the inner face thereof.

In the embodiment of the invention illustrated in FIGS.

It will be apparent that the effective infusion area of the material thus deposited corresponds to the area of the bag material in contact with the infusion material. In a modified form of the invention, as illustrated in FIG. 5, the fiat bag may be provided with an addi- -tional sealed portion 36 extended medially thereof and joining opposed side walls of the bag to form two separate' compartments 38, 40. When the predetermined quantity of infusion material is deposited equally in both compartments 38, 40, the material will assume a higher level in the bag compartments as indicated by the dot and dash lines 42, 44, thus providing a relatively greater infusion area of material in contact with the bag for more eflicient infusion.

Referring now to FIG. 6, diagrammatically illustrating the various steps followed in accordance with a preferred method of continuously-producing successive filled and sealed bags of the character described from a continuously moving web of bag forming material, and wherein each bag is provided with a handle, a web 112 of bag forming material may be continuously advanced over a suitable supporting plate indicated at 101. In practice the web 112 may be withdrawn from a roll 103 thereof, and in order to facilitate subsequent folding of the web along a central longitudinal line a scoring or indenting roller indicated at 105 may be pressed against the supply roll of the bag forming material to provide a lightly scored central line 114 as also indicated in FIG. 7. As the elongated web 112 is continuously advanced, a series of tags 118 are loosely placed upon the web in spaced relation,

corresponding to the center lines of the subsequently formed bag sections. The tags are preferably placed on the web with one edge thereof aligned with a marginal edge of the web as indicated in FIG. 8, and the loosely placed tags may be held in operative relation to the web by suction means indicated generally at 107 cooperating with openings 109 formed in the supporting plate and arranged to apply suction to the underside of the web and through the porous filter paper to retain the tags in their applied position. While thus held, successive tags may be lightly heat sealed to the thermoplastic paper web to provide a relatively small sealed area 120, as also shown in FIG. 9, such as to permit subsequent detachment of the tag.

The next step in the method of producing successive fbags provided with handles is the placing of successive short distance, and the other end of each string is arranged to extend a short distance beyond the opposing marginal edge of the web 112 as indicated at 126 and as also shown in FIG. 10. During placement of successive strings 116 on the web each string is lightly heat sealed to the web at selected points indicated at 122, 124,

128, see FIG. 10, the lightly heat sealed portions being such as to permit subsequent detachment when the handle is extended for use. The portion of the string overlying the tag is then permanently heat sealed to the tag as indicated at 117 in FIGS. 6 and 11, and the extended portion 126 is then folded over and under the opposite marginal edge of the Web and heat sealed thereto as indicated at 119 in FIGS. 6 and 12. As will hereinafter appear, the turned-under portion 126 will occur between the sealed mouth portions of the subsequently formed bags to connect the handle to the bag.

. The continuously advanced Web with its attached handles may then be inverted. As illustrated in FIG. 6, the handles are attached to the upper face of the web during its travel from right to left through an upper run, and

. the web is conveniently inverted by merely leading the web through a semicircular path into a lower run wherein the web is advanced in the opposite direction, or from left to right as indicated in FIG. 6, with the handles disposed 7 0. on the underside of the web as also shown in FIG. 13.

The web may then be folded longitudinally upon itself along the slightly indented center line 114 to provide a folded strip open at the top as shown in cross section in FIG. 14. The continuously moving strip may then be heat sealed at spaced transverse zones 130, intermediate the space between successive attached handles, to provide a series of connected bag sections open at the top each having a handle attached thereto. During the continuous travel of the strip along the lower run the bag sections are each provided with a charge of the commodity being packaged, such as tea, by continuously moving funnels indicated generally at 131, and upon removal of the funnels the mouths of the bag sections may be sealed, as by heat sealing rollers indicated at 133, 135 to produce the top closing seals 134. Thereafter, successive bag sections may be severed through the transversely sealed zones 130 in any suitable manner, as by a traveling knife blade 137, to produce the individual bags each provided with a handle comprising a tag and a string as shown in FIG. 15.

It will be observed that folding of the web upon itself in the manner described effects wrapping of the handles about the bags and that the turned-under ends 126 of the strings 116 are sealed between the walls of the mouth portions during the top sealing operation. Thus, the individual bags produced in accordance with the present invention are each provided with a handle comprising a tag and a string wrapped about the bag with one end of the string secured to the tag and With the other end of the string secured to the bag. The tag and the portions of the string which are lightly heat sealed to the bag may be easily broken away at the points 20, 22, 24 to extend the handle for use as illustrated in FIG. 16. It will be observed that during the top sealing operation the lightly heat sealed portion 128 occurs at the sealed mouth portion and becomes permanently heat sealed to the outside of the bag against the two-ply mouth portion during the top sealing operation. Thus, when the handle is extended, the string Will be secured to the bag at point 128. However, in the event that this portion 128 is inadvertently broken away from the bag material, the end 126 of the string is still held between the sealed mouth portions as described. It will also be observed that the upper marginal edge of the tag also occurs in the top sealed edge but may be easily broken away during subsequent use to extend the handle because the outer face of the bag material contains less thermoplastic material than the inner face thereof.

, Referring now to FIGS. 17 and 18, instead of heat sealing the mouths of the bag sections and severing the individual bag sections in the manner illustrated in FIG. 6, the continuous strip of connected bag sections open at their months may be separated into predetermined lengths containing a predetermined number of bag sections, the number of bag sections in each length preferably corresponding to the number, herein shown as eight bag sections, which will subsequently be contained in an individual package sold to the consumer. In practice the strip of connected bag sections may be separated into lengths of eight bag sections by first perforating or partially cutting through every eighth transversely sealed zone 130. This partial cutting operation may preferably be accomplished during the transverse heat sealing operation by a cutter carried by every eighth one of the continuously traveling transverse heat sealing elements. The continuous strip may then be advanced longitudinally, and by causing the leading portion of the strip to travel slightly faster than the normal travel during the sealing operation, successive leading lengths of eight sections each may be separated from the continuous strip along the partially cut lines. In FIG. 17 the continuous length of connected bag sections is indicated in general by the numeral 139, and a length of eight sections separated therefrom is indicated in general by the numeral 141. Each length of eight sections may then be heat sealed as a unit in any usual or preferred manner, such as by the opposed elongated heat sealing elements 143, 145, whereupon the length of eight sections may be supported and moved as a unit into engagement with stationary knife blades 146 to produce the individual bags. Successive lengths thus severed as a unit provide successive groups 6 of eight individual bags which may thereafter be deposited in individual packages for sale to the consumer.

While the present method of producing filled and tagged bags has been herein illustrated and described as adapted for producing infusion bags, it will be understood that the present method and the novel individual steps thereof may be employed in producing filled and tagged bags containing other commodities.

This application is a continuation-in-part of my copending application for Infusion Bag and Method of Making the Same, Serial No. 660,011, filed May 17, 1957.

Having thus described the invention, What is claimed is:

l. A method of producing a filled and sealed bag having a handle comprising a tag and a string, the steps comprising providing a sheet of bag forming material, applying and attaching the handle to one face of the bag material with an extended end of the handle folded over a marginal edge of the sheet, folding the sheet of bag material upon itself with the handle attached to the outer surface thereof to eifect wrapping of the handle about the outer surface of the folded sheet, sealing the side edges to provide a bag open at the mouth, filling the bag, and then sealing the mouth thereof with said extended end of the handle sealed between the walls of the mouth portion.

2. A method of producing a filled and sealed bag having a handle comprising a tag and a string, the steps comprising providing a sheet of bag forming material, applying the extended handle lengthwise of the sheet and detachably securing selected portions of the handle thereto, folding the sheet upon itself to effect wrapping of the handle about the outer surface of the folded sheet, sealing the side edges of the sheet to provide a bag open at the mouth, filling the bag, and then sealing the mouth of the bag with one end of the handle inserted between the walls of the mouth portion.

3. The method according to claim 2 wherein the bag forming material and the string comprise heat scalable materials, and wherein the step of detachably securing the handle to the sheet comprises a heat sealing operation, and the steps of sealing the side edges and the mouth of the bag comprise heat sealing operations.

4. A method of making an infusion bag having a handle comprising a string and a tag attached thereto and wrapped around the bag which consists in placing the handle longitudinally on a sheet of bag forming material with the tag disposed adjacent one end of the sheet and the string overlying a portion of the tag at one end and extending a short distance beyond the sheet at the other end, sealing the string to the tag and lightly sealing the tag and the string to the sheet at selected relatively small sealing areas capable of being subsequently broken to extend the handle, folding the sheet and handle assembly in half and sealing the side edges to provide a bag, depositing infusion material into the bag, folding the extended end of the handle inwardly between the walls of the mouth of the bag, and sealing the mouth. I

5. A method of making an infusion bag having a handle comprising a string and a tag attached thereto and wrapped around the bag which consists in providing a rectangular sheet of heat scalable bag forming material, placing a tag on the sheet with one edge of the tag aligned with one edge of the sheet and disposed substantially medially of the longitudinal marginal edges of the sheet, placing a length of heat scalable string material longitudinally and centrally of the sheet with one end overlying the opposite edge of the tag and the other end extending a short distance beyond the opposite edge of the sheet, heat sealing the sheet and handle assembly to secure said overlying end of the string to the tag and to secure the other end of the string to said opposite edge of the sheet, and lightly heat sealing the tag and the string to secure said one edge of the tag to the sheet and to secure the string to the sheet at selected relatively small sealing areas capable of being subsequently broken to extend the handle for use, folding the extended end of the string over 7 the adjacent edge of the sheet, then folding the sheet and handle assembly in half and heat sealing the side edges of the sheet to provide a bag, depositing a quantity of infusion material into the bag, and then beat sealing the mouth of the bag with the folded end of the string heat sealed between the walls of the mouth of the bag.

1 6.-A method of producingsuccessive filled and sealed bags of the type provided with one folded edge, each'having a handle comprising a tag and a string, which includes the steps of advancing an elongated web of bag forming .material, applying and attaching successive handles in spaced relation to one surface of the web with an extended end of each handle folded over a marginal edge of the web, and then folding, filling and sealing the remaining edges of the bags with said extended ends of the handles sealed between the walls of one of said sealed edges.

7. A method of producing successive filled and sealed bags, each having a handle comprising a tag and a string, which includes the steps of continuously advancing an elongated web of bag forming material, applying and attaching successive handles in spaced relation to one surfaceof the web, folding the web longitudinally upon itself to provide a strip open at the top and with the attached handles wrapped about the outer surface of the strip, and sealing the web along spaced transverse zones intermediate successive handles to provide a series of connected .bag sections.

, 8. A method of producing successive filled and sealed bags, each having a handle comprising a tag and a string, which includes the steps of continuously advancing an elongated web of bag forming material, applying and attaching successive handles in spaced relation to one surface of the web, folding the web longitudinally upon itself to provideya strip open at the top and with the attached handles wrapped about the outer surface of the strip,

sealing the web along spaced transverse zones intermediate the handles to provide a series of connected bag sections open at their mouths, depositing successive charges of a commodity into successive bag sections, sealing the mouth portions with an end of each string inserted and sealed between the walls of the sealed mouth portions, and then severing the bag sections through said transverse zones to produce individual bags.

9. The method defined in claim 8 wherein the bag forming material and the string comprise heat sealable materials, and wherein the tag and portions of the string are lightly heat sealed to the bag material and capable of being broken away from the bag to extend the handle for use.

10. A method of producing filled and sealed bags, each having a handle comprising a tag and a string, the steps comprising continuously advancing an elongated web of bag forming material, applying and attaching successive handles in spaced relation to one surface of the web, folding the web longitudinally upon itself to provide a strip open at the top and with the attached handles wrapped about the outer surface of the strip, sealing the web along spaced transverse zones intermediate the handles to provide a series of connected bag sections, depositing successive charges of a commodity into successive bag sections to provide a continuous strip of filled and connected bag sections, separating the continuous strip of filled and connected bag sections into predetermined lengths, each containing a plurality of bag sections, sealing the mouths of the predetermined--lengths as a unit with one end of each string sealed in its mouth portion,

and then severing the bag sections of each length as a vidual bag sections.

a 11. The method according to claim 10 wherein-the step of attaching the handles to the web comprises lightly heat sealing the tag and portions of the string to the bag material and capable of being broken away from the completed bag to extend the handle for use:

12. The method according to claim 10 wherein a por tion of each string attached to the web is folded under the marginal edge of the web to present the folded-under portion between the walls of the mouth portion of the subsequently sealed bag.

7 13. A method of producing filled and sealed bags, each having a handle comprising a tag and a string, the steps comprising advancing a web of bag forming material, placing and lightly sealing successive tags in prede-= termined spaced relation along one marginal edge of the web, applying successive lengths of string transversely of the web in alignment with successive tags and lightly heat sealing selected portions of the string to the web, sealing one end of the string to the tag, folding under and sealing extended portions of the string to the underside of the opposite marginal edge of the web whereby to provide a continuous web provided with spaced handles attached to one surface of the web prior to forming, filling and sealing the bags.

14. A method of producing filled and sealed bags, each having a handle comprising a tag and a string, the steps comprising advancing a web of bag forming material, placing and lightly sealing successive tags in predetermined spaced relation along one marginal edge of the web, applying successive lengths of string transversely of the web in alignment with successive tags and lightly heat sealing selected portions of the string to the web, sealing one end of the string to the tag, folding under and sealing extended portions of the string to the underside of the opposite marginal edge of the web whereby to provide a continuous web provided with spaced handles attached to one surface of the Web, inverting the web to dispose the attached handles on the underside of the web, folding the web longitudinally upon itself to provide a strip open at the'top and with the attached handles wrapped about the outer surface of the strip, sealing the strip along spaced transverse zones intermediate the. space between successive handles to provide a series of con nected bag sections, depositing successive charges of a commodity into successive bag sections, sealing the mouth portions with the folded-under portion of each string sealed between the walls of its mouth portion, and then severing the bag sections through said transverse zones to produce individual bags.

15. The method defined in claim 14 which includes the step of lightly scoring the web along its longitudinal center line as it is advanced whereby to facilitate subsequent folding of the web upon itself.

16. The method defined in claim 14 wherein the web comprises a thermoplastic bag forming material, and

wherein the sealing operations comprise heat sealing operations.

References Cited in the file of this patent UNITED STATES PATENTS

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