US2144154A - Method and apparatus for closing bags - Google Patents

Description

Jan. 17, 1939. R. E. HoczKMAN` METHOD AND APPARATUS .FOR CLOSING BAGS Filed Aug. l2, 1937 '3 Sheets-Sheet l /M/EN TUF; @0555' Hm/WAM 'f7/5 ATTU/wfx Jan. 17,1939.

R. E. HOCKMAN 2,144,154

METHOD AND APPARATUS FOR CLOSING BAGS Filed Aug. l2, 1957 3 Sheets-Sheet 2 Jan. 17, 1939. R. E. HOCKMAN 2,144,154

METHOD AND APPARATUS FOR CLOSING BAGS Filed Aug. l2, 1937 5 Sheets-Sheet 5 /1/'5 A TTFP/VE Y Patented Jan. 17, 1939 PATENT oPPlcE l MErHon AND APPARATUS Fon CLOSING.-I

BAGS

`Roger E. Hockman, Middletown, Ohio, assignor to The Raymond Bag Company, Middletown, Ohio, a corporation of Ohio Application August 12, 1937, Serial No. 158,774

19 Claims.

This invention relates to a method andapparatus for closing bags and is designed primarily for use in the manufacture ofl bags, although it may be utilized when bags are closed after having 4been lled.

In the manufacture of bags, and more particula'rly in the manufacture of heavy duty paper bags, it is customary to sever from a continuous tube, or nest of tubes, bag length sections which are then sewed across the ends thereof to close the same and form the completed bag. Where both ends of the bag are sewed avalved opening is provided at one end of the bag through which the same may be filled. Usually a tape, such as a strip of paper, is folded about and pasted to j th adjacent ends of the side walls of the bag section and the section is sewed through both lthe tape and the side walls. It.is also common .i i practice to apply to one side of the tapea sealing member, usually of soft cord, and to sew through the sealing member, tape and sidewalls. Such a closure is satisfactory for many purposes but it willnot entirely prevent the escape from the bag of finely powdered material and it is not moisture proof, as the sealing member and sewing thread, or stitches, will absorb moisture from the atmosphere which will travel along the stitches into the closure and thus bcome in contact with the contents of the bag, which of course is objectionable. In some instances the -contents are of -such a character that the contact `of moisture therewith will produce a chemical reaction'which may weaken or destroy the closure.

One object of the present invention is to provide a bag closure of this type which will prevent the escape of very finely powdered material from the bag.

A further object of the invention is to provide such a closure which will be moisture proof andA in Fig. 1, partly broken away; Fig. 3 is a plan' View of a portion of the tape which is applied to the ends of the bag sections; Fig. 4 is a side elevation of the end portion of a bag closed in accordance with my invention; Fig. 5 is a secin the usual manner.

tional view taken transversely through the closure; Fig. 6 is a section taken lengthwise through a partially completed closure; Fig. 7 is a transverse section of the presser plate; Fig. 8 is a side elevation of the presser foot; and Fig. 9 is a detail View, partly in section, of the apparatus for impregnating the sealing member with wax.

In practicing the invention I apply to one side of the bag section, adjacent the end thereof, an elongate sealing member, such as a cord, which has been treated with wax and then stitch this wax treated sealing member to the bag section As the thread passes through the sealing member portions of the wax will adhere thereto andbe carried into the needle openings and if the wax is in a molten or semimolten state at the time the stitching takes place suiiicient wax may be carried into the needle openings to seal the same. However, I prefer to subject the sewed closure, and particularly the wax treated sealing member, to heat which will soften the wax and cause the same to flow along the thread or stitches into the needle openings, thus impregnating the thread and completely lling the openings with wax.

In carrying out the method in its preferred form the tape I0 which is to be folded about the end of the bag section II is first provided with a plurality of strips of paste, there being preferably three such strips I2 and I3, as shown in Figs. 3 and 5. 'I'he two lateral strips of paste I2 are arranged near the lateral edges of the tape so that when the latter is folded about the end of the bag section said paste strips will contact Y the respective side walls of the bag section along lines spaced some distance from the ends thereof. The intermediate strip of paste I3 is of a width substantially greater than the lateral strips and is so arranged that when the tape is folded about the bag section this intermediate strip of paste will engage the edges of and overlap theiend portions of the side walls of the bag, as shown in Fig. 5. The sealing member, which is shown as a soft cord I4, is treated with wax, preferably by passing the same through a bath of molten wax, such as paraffin, so as to impregnate the sealing member with the wax, and is guided from the bath onto one side of the folded tape III. When the tape and sealing member have been applied to the end of the bag section the latter is sewed through the sealing member, the'tape and the side walls. The bath of molten wax is so located with relation to the sewing mechanism that the wax will be in a soft or semi-molten con-v dition at the time the sewing takes place. After the closure has been stitched it is subjected to the action of heat which will soften the wax and cause the same to penetrate the stitches I5 and needle openings through which the stitches extend, as above described.` The sealing member and stitches are thus rendered impervious to moisture and the needle openings are completely filled with wax. As a result no moisture can enter the bag along the stitches or needle openings and no material can escape from the bag through the needle openings. By pasting the tape to the end edges of the side walls of the bag section, as shown in Fig. 5, the passage of material between these end edges is entirely prevented. The ends of the tape usually extend a short distance beyond each side of the bag, as shown in Fig. 4, and those parts of the pasted strip which extend beyond the sides of the bag section will each have its side portions pasted one to the other, thus effectively closing the ends of the folded tape.

Any suitable apparatus may be vprovided for carrying out the method as above described and in the present drawings I have utilized a. bag sewing machine of a well known type to which has been added such additional apparatus as was necessary to effect the desired operations. The sewing machine as a Whole is shown in the Sharkey Patent No. 1,915,765 of June 27, 1933, and it is not necessary to here illustrate or describe the same in detail. It will be noted that the sewing machine comprises a supporting structure or table I 6 over which moves a. conveyor, here shown as two endless chains I1 provided with lugs I8 toengage the edges of the bag sections I3v and move the same transversely to their length along the supporting structure to a sewing head which overhangs the path of the end portions of the bag sections and is adapted to perform the necessary sewing operations. The bag sections are held in engagement with the lugs on the conveyor by a series of longitudinal rods 45 supported at their ends by transverse bars 46 which in turn are supported by uprights Orstandards 41 extending upwardly from the supporting structure. Inasmuch as the sewing head 20 forms no part of the linvention it is unnecessary to illustrate or describe its construction or opera-tion. This particular sewing machine is a double machine, that is, it is adapted to simultaneously sew both ends of a bag section and is therefore provided on each side with a sewing head 20. In adapting this machine to the present purpose additional parts have been associated with both sewing heads but inasmuch as these parts are duplicates the description of one apparatus will apply to both.

The tape I0 is fed from a suitable source of supply, such as a roll of tape not here shown, through a paste applying device, which is shown in Figs. 1 and 2, and comprises a roller 2| over which `the tape is drawn and three disks 22 and 23 carried by a common shaft 24, rotating in a paste receptacle 25 and applying the paste to the tape as the latter passes over the roller 2|. The tape passes from the paste applying device over a guide roller 26 to a folding device 21, of conventional construction, which folds the same about the ends of the bag sections as the latter `move toward the sewing head.

The means for impregnating the sealing mem- Iber with wax may take various forms but preferably this is accomplished by passing the sealing `member through a bath of molten wax and, as here shown, this bath is contained in a receptacle 28 which is provided with an electric heater 29. Any suitable means may be provided for guiding the sealing member through the bath of wax and, in the present instance, where the sealing member is shown as a cord, the guiding means comprises a tube 30 carried by the receptacle 28 and having a downwardly curved portion 3l thereof immersed in the molten wax and provided with a plurality of openings, such as the elongate slots 32, to permit the molten wax to contact with the cord. One of the slots, the last one which the cord passes, has its upper end arranged above the level of the liquid in the receptacle and the diameter of the tube with relation to the thickness of the cord is such that the end wall 33 of this slot will act on the cord with a wiping action to remove therefrom surplus wax and return the same to the receptacle. The end of the tube on one side of the receptacle 28 is turned downwardly to receive the cord as it is drawn from a suitable source of supply, here shown as a ball of cord 34 supported on a shelf 35a. Ihat portion of the tube on the other side of the receptacle 28 extends from the receptacle to a point above the folded tape in advance of the sewing head so that as the sealing cord leaves the tube I4 it is applied to the tape, and the discharge end of the tube I4 is so arranged that this cord will be located on the tape between the pasted portions of the latter.

Associated with the sewing head is a plate 35 which exerts pressure on the tape to cause the pasted portions thereof to adhere firmly to the walls of the bag section, and which preferably constitutes the presser-foot of the sewing machine. This plate is provided in its lower side with a longitudinal groove or guideway 36 to receive and permit the passage of the sealing cord. That end of the plate 35 in advance of the needle 3l of the sewing head is turned upwardly, as shown at 38, and provided with anA opening 33 which merges into the groove 36 and the outer end of which is arranged to receive the sealing cord from the tube 30. With the walls of the bagsection, the two sides of the tape and the sealing member thus arranged in superposed relation tohe needle 31 of the sewing head operates through an opening 40 in the plate 35 to stitch these several parts one to the other.

Any suitable means may be employed for applying heat to the bag closure for the purpose of again softening the wax and this means may be located in any suitable relation to the sewing head. 'I'he tape and sealing cord are continuous -a light pressure which will expedite the fiow of melted wax therefrom along the stitches. When the bag section leaves the heating members 42 the closure has been'completed and the finished bag is discharged from the machine.

The tape I3 and sealing cord I4 are drawn from their sources of supply respectively through the tape supplying device land the waxbath by Preferably the memtheir connection with the bag sections which it is unnecessary to provide other means for feeding the same to the bag sections. For simplicity of illustration I have illustrated the invention as applied to a single ply bag, that is, a bag formed from a single tube but it will be understood that the invention is equally applicable to multi-wall bags, that is, bags formed from a plurality of nested tubes.

While I have shown and described the preferred method of practicing my invention and one form for carrying out that method I wish it to be understood that I do not wish to be limited to the details thereof as various modifications of the method and of the apparatus may occur to a person skilled in the art.

Having now fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. The method of closing the end of a bag which comprises treating a moving sealing men ber with Wax, applying said sealing member to the outer surface of one side wall of a moving bag, stitching said sealing member to both Walls of said bag, and heating said sealing member to soften the wax and cause the same to enter the openings formed in said bag walls by the stitching.

2. The method ofclosing the end of a bag which comprises folding a moving tape about the adjacent ends of the two side walls of a moving bag, treating a moving sealing member with wax, applying said sealing member to said tape on one side of said moving bag-stitching said sealing member and said tape to said side Walls, and subjecting said sealing member to heat to soften said wax and cause the same to flow `along the stitches and through the needle openings in said tape and said walls.

3. The method of closing the end of a bag which comprises impregnating a sealing member with molten wax, arranging said sealing member on one side of said bag and sewing the same to both walls of said bag before said yvax has solidified, and thereafter subjecting said sealing member and the sewed portion of said bag to heat to soften the wax and cause the same to spread throughout the openings formed in the bag walls by the sewing operation.

4. The method of closing the end of a bag which comprises folding a tape about the adjacent `ends of the two side walls of the bag and pasting the same to said side walls, impregnating a sealing member with molten wax, applying said sealing member to said tape and sewing said sealing member and said tape to said side walls before said wax has. solidified.

5. The method of closing the end of a bag which comprises folding a tape about the adjacent ends of the two side walls of the bag and past-ing the same to said side walls, impregnating a sealing member with molten wax, applying said sealing member to said tape, sewing said sealing member and said tape to said side walls, and thereafter applying heat to said sealing member to soften the wax and cause the same to permeate the stitches and fill the needle openings in said side walls.

6. The method of closingthe end of a bag which comprises imparting continuous movement to a bag section transversely to its length, folding a tape about the open end of the moving bag section, passing a, sealing cord through a bath of molten wax, applying said cord to said tape at one side of the moving bag section, and sewing said cord and said tape to the side walls of said moving bag section.

'7L The method of closing the end of a bag which comprises imparting continuous movement to abag section transversely to its length, folding a tape about the open end of the moving bag section, passing a sealing cord through a bath of molten wax, applying said cord to said tape at one side of the moving bag section, sewing said cord and said tape to the side walls of said moving bag section, and thereafter applying heat to the sewed end of said moving bag section.

8. The method of closing the end of a bag which comprises folding a tape about the adjacent ends of the side walls of said bag, pasting the intermediate longitudinal portion of said tape to the edges of said walls, pasting the lateral portions of said tape to the respective walls along lines spaced from the edges thereof, impregnating a sealing member with wax, applying said' sealing member to one side of said tape between the pasted portions of the latter, sewing said sealing member and said tape to said walls, and applying heat to said sealing member to soften said wax.

9. The method of closing the end of a bag `which comprises folding a tape about the adjacent ends of the side Walls of said bag, passing a sealing cord through a bath of molten wax, removing surplus wax froml said cord, applying said cord to said tape on one side of said bag, and

sewing said cord and said tape to said side walls.

v10. In a bag sewing machine, means for moving a bag section transversely to its length, means for impregnating a sealing member with wax, means for applying said impregnated sealing member to one side of said moving bag section in spaced relation to the end of the latter, a sewing head arranged to act on said bag' section to stitch said sealing member to the walls of said bag section, and means for applying heat to said sealing member.

l1. In a bag sewing machine, means for moving a bag section transversely to its length, means for impregnating a sealing member with wax, means for applying said impregnated sealing member to one side of said moving bag section in spaced relation to the end of the latter, a sewing head arranged to act on said bag section to stitch said sealing member to the walls of said b-ag section, and a heater arranged beyond said sewing head adjacent to the path of said sewed end of said bag section.

12. In a bag sewing machine, means for moving a` bag section transversely to its length, means for folding a tape about one end of said moving bag section, a receptacle for molten wax, means for guiding a sealing member through the molten wax in said receptacle and onto said folded tape, and a sewing head arranged to stitch said sealing member and said tape to the walls of said bag section.

13. In a bag sewing machine, means for moving a bag section transversely to its length, means for folding a tape about one end of said moving bag section, a receptacle for molten wax, means for guiding a sealing member through the molten wax in said receptacle and onto said folded tape, a sewing head arranged to stitch said sealing member and said tape to the walls of said bag section, and a heater arranged beyond said sewing head and `adjacent to the path of the stitched end of said bag section.

14. In a bag sewing machine, means for moving a bag section transversely to its length, means for folding a tape about one end of said said moving bag section, a receptacle for moltenv wax, means for guiding a sealing member through the wax in said receptacle and onto said folded tape, a plate arranged above the path of the end portion of said bag section to exert pressure on said tape and having a groove to receive said sealing member, and means adjacent to said plate for sewing said sealing member and said tape to the walls of said bag section.

16. In a bag sewing machine, means for moving a bag section transversely to its length, means for folding a tape about one end of said moving bag section, a receptacle for molten wax, means for guiding a sealing member` through the molten wax in said receptacle and onto said folded tape and for removing surplus wax from said sealing member, and means for sewing said sealing member and said tape to the walls of said bagsection.

17. In a bag sewing machine, means for moving a bag section transversely to its length, means for folding a tape about one end of said moving bag section, a receptacle for molten wax,

a tube extending through said receptacle, havingopenings therein and arranged to guide a sealing member through the molten wax in said receptacle, means to guide said sealing member onto said tape, and means for sewing said sealing member and said tape to the walls of said bag section.

18. In a bag sewing machine, means for -moving a. bag section transversely to its length, means for applying paste to a continuous tape, means for folding said tape about the end of said moving bag section, a receptacle for molten wax, a tube arranged to guide a sealing cord onto said tape and having a portion immersed in the molten wax in said receptacle and provided with openings, one of said openings having an end Wall arranged above the level of said wax to remove surplus wax from said cord, a plate to exert pressure on said tape, having a longitudinal guideway arranged to receive said cord from said tube and having a transverse opening, means including a needle operating through the opening in said plate to sew said cord and said tape to the walls of said bag section, and heating elements arranged beyond said sewing means to receive between them the sewed end of said bag section.

19. The method of closing the end of a bag which comprises saturating a sealing member of soft absorbent material with molten wax, arranging said sealing member on one side of said bag and sewing the same thereto by stitching through said sealing member, the Wax therein and both side Walls of said bag before the wax has solidified. l

ROGER E. HOCKMAN.

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