US3322327A - Internal j-shaped valve for flexible bags - Google Patents

Description

May 30, 1967 G. M. PRAM. 3,322,327

INTERNAL J-SHAPED VALVE FOR FLEXIBLE BAGS Filed June 2, 1966 m @MW United States Patent Gli 3,322,327 INTERNAL J-SHAPED VALVE FOR FLEXIBLE BAGS George M. Prall, Barrington, lill., assignor to National Distillers and Chemical Corporation, New York, N.Y., a corporation of Virginia Filed June 2, 1966, Ser. No. 554,709 3 Claims. (Cl. 229-625) This invention relates to a novel patch valve for plastic bags, and more specifically relates to the use of a novel internal I-shaped insert for defining an internal valve for a plastic bag which provides improved valve integrity.

The use of valve openings in plastic bags is well known to the art, where such valves can accommodate a filling spout insert into a closed bag. An internal patch having a free internal open end is commonly placed over the interior of a slotted opening in the wall of the bag to prevent the escape of the bag contents after it is filled, hereinafter referred to as sifting of the bag contents.

In accordance with the present invention, the internal patch is formed of a light gauge plastic film which is heat sealed over the interior surface of the slot in the bag wall. The patch has a J-shaped fold with both the short and long leg of the J-shaped body having their common end sealed in front of the slot, with the body of each leg extending beyond the rear of the slot, thereby to provide improved valve integrity.

When using the novel J -shaped valve in the above noted manner, the valve offers two free edges internally of the bag to prevent sifting of the bag contents from the valve after filling. The interior-most portion of the l-shaped iiap acts in a manner similar to any type of internal patch and will crumple as the contents of the bag move toward the valve opening when the bag is removed from the lling spout and placed in some different position. This crumpling action on the main body or long leg of the J- shaped valve prevents most of the bag contents from sifting from the valve.

In accordance with the invention, however, the smaller J-portion of the flap defines a second edge just inside the bag opening and will further prevent the sifting of residual material left in the valve area by the withdrawal of the loading spout, as well as to preventing sifting of material entering the valve area before it has been fully sealed by the major portion of the inner flap.

Accordingly, a primary object of this invention is to provide a novel internal valve for plastic bags which has improved valve action.

Yet another object of this invention is to provide the effect of two serially connected valve fiaps adjacent the valve slot of a plastic bag whereby the last valve controls any sifting through the first and major valve portion.

These and other objects of this invention will become apparent from the following description when taken in connection with the drawings, in which:

FIGURE l is an exploded perspective view showing a bag body and the J-shaped internal flap which is to be connected thereto.

FIGURE 2 illustrates the l-shaped internal valve of FIGURE l when sealed into the open end of the bag and across the slotted opening in the bag.

FIGURE 3 is a front view of the bag of FIGURE 2 after the upper edge has been sealed to close the bag and complete the valve connection.

FIGURE 4 is a cross-sectional view of FIGURE 3 taken across the line 4--4 in FIGURE 3.

FIGURE 5 is a cross-sectional View of FIGURE 3 taken across the line 5-5 in FIGURE 3.

Referring fiirst to FIGURE 1, there is illustrated therein a typical bag of any suitable plastic material which has 3,322,327 Patented May 30, 1967 ice yfront and rear panels 11 and 12 joined in FIGURE l by the side gussets 13 and 14. It will become apparent that the present invention is applicable to any type of bag and that the gusseted bag of FIGURE 1 is used for illustrative purposes only.

The bottom of bag 10 then has a heat seal 15 extending thereacross to seal panels 11 and 12 at their bottom. The upper portion of panel 11 then has a slot 16 extending therethrough which will provide access for a filling spout to the interior of the bag when the bag is closed. An internal patch valve 17 of a thin exible thermoplastic material is then placed across the interior of slot 16 to prevent sifting of the contents of the bag 10 after the bag is filled through slot 16.

In accordance with the invention, the internal valve 17 has a J-shape, as illustrated in FIGURE 1, which has a relatively long body portion 13 and an inwardly turned relatively short body portion 19. The patch 17 is then applied to the open bag, as shown in FIGURE 2, wherein the bottom region of the J-shape is sealed in front of slot 16 as along a heat seal 2l), while the lower side of l-shaped valve insert 17 is sealed along a portion thereof by the heat seal 21. The relatively long fiap portion 18 extends beyond the left-hand end of seal 21 and appreciably beyond the slot 16, while the relatively short section 19 of patch valve 17 extends just beyond slot 16.

After the l-shaped insert 17 is sealed to the bag, as shown in FIGURE 2, the upper end of the bag is closed by a heat seal 22, shown in FIGURE 3, which extends completely along the upper e-nd of the bag and extends from the front panel 11 to the rear Apanel 12 of the bag. -Note that the patch valve sections 18 and 19 will be included in this seal Where they are interposed between panels 11 and 12.

The section 18 of the insert 17 will now operate in the manner of a standard internal flap in a valve bag whereby, as may be best understood from FIGURES 4 and 5, a filling spout can be inserted into the bag through slot 16 a-nd along the channel 23 (FIGURE 4) defined between panel 11 and the opposing surface section 13 of the valve. `Once the spout has filled the bag and is removed from channel 23, the ap 18 can crumple against the inner surface of panel 18 to prevent sifting of the bag contents out through slot 16.

In accordance with the invention, the use of the I- shaped flap provides a second valving ap comprised of section 19 which extends just beyond the slot 16, as shown in FIGURE 4, to serve as a second-ary valve to prevent the sifting of material from the bag which may have been trapped in channel 23 or otherwise enters channel 23. Therefore, the novel I -shaped valve provides an improved valve action to substantially eliminate all sifting of the bag contents.

Although this invention has been described with respect to its preferred embodiments, it should be understood that many variations and modifications will now be obvious to those skilled in the art, and it is preferred, therefore, that the scope of the invention be limited not by the specific disclosure herein, but only by the appended claims.

The embodiments of the invention in which an exlusive privilege or property is claimed are defined as follows:

1. A valve for a iiexible plastic bag; said plastic bag having a front panel having an interior surface; said front panel havin-g a slot therein; said valve comprising a relatively long fiexible plastic sheet and a relatively short flexible plastic sheet; first, second and third heat seals connecting said relatively short and relatively long plastic sheets to said interior surface of said front panel and across said valve; said first heat seal extending parallel to said slot and laterally displaced therefrom and extending through said fro-nt panel and one end region of each of said relatively short and relatively long sheets; said second and third heat seals extending perpendicular to said slot and passing across regions adjacent the ends of said slot; said second and third heat seals extending through said front panel and through opposite side edges of each of said relatively long and relatively short sheets; said relatively shor-t sheets interposed between said interior surface of said front panel and a portion of said relatively long sheet; said relatively short sheet having a free edge extending beyond said slot; said relatively long sheet having a free edge extending beyond said free edge of said relatively short sheet.

2. The valve as set forth in claim 1 wherein said relatively long sheet and relatively short sheet are comprised of an integral sheet of plastic material bent in the form of a I.

3. The valve as set forth in claim 1 wherein said slot extends in the direction of the length of said exible plastic bag land adjacent one side edge thereof; said second heat seal extending along the full top edge of said bag and sealing closed the top of said bag.

References Cited UNITED STATES PATENTS 3,180,558 4/1965 Quaadgrass et al. 229-625 3,197,119 7/1965 Hartig et al. 22962.5 3,268,152 8/1966 SWa-rtZ 229-62.5 FOREIGN PATENTS 954,273 4/ 1964 Great Britain.

JOSEPH R. LECLAIR, Primary Examiner. D. M. BOCKENE-K, Assistant Examiner.

Claims (1)

1. A VALVE FOR A FLEXIBLE PLASTIC BAG; SAID PLASTIC BAG HAVING A FRONT PANEL HAVING AN INTERIOR SURFACE; SAID FRONT PANEL HAVING A SLOT THEREIN; SAID VALVE COMPRISING A RELATIVELY LONG FLEXIBLE PLASTIC SHEET AND A RELATIVELY SHORT FLEXIBLE PLASTIC SHEET; FIRST, SECOND AND THIRD HEAT SEALS CONNECTING SAID RELATIVELY SHORT AND RELATIVELY LONG PLASTIC SHEETS TO SAID INTERIOR SURFACE OF SAID FRONT PANEL AND ACROSS SAID VALVE; SAID FIRST HEAT SEAL EXTENDING PARALLEL TO SAID SLOT AND LATERALLY DISPLACED THEREFROM AND EXTENDING THROUGH SAID FRONT PANEL AND ONE END REGION OF EACH OF SAID RELATIVELY SHORT AND RELATIVELY LONG SHEETS; SAID SECOND AND THIRD HEAT SEALS EXTENDING PERPENDICULAR TO SAID SLOT AND PASSING ACROSS REGIONS ADJACENT THE ENDS OF SAID SLOT; SAID SECOND AND THIRD HEAT SEALS EXTENDING THROUGH SAID FRONT PANEL AND THROUGH OPPOSITE SIDE EDGES OF EACH OF SAID RELATIVELY LONG AND RELATIVELY SHORT SHEETS; SAID RELATIVELY SHORT SHEETS INTERPOSED BETWEEN SAID INTERIOR SURFACE OF SAID FRONT PANEL AND A PORTION OF SAID RELATIVELY LONG SHEET; SAID RELATIVELY SHORT SHEET HAVING A FREE EDGE EXTENDING BEYOUND SAID SLOT; SAID RELATIVELY LONG SHEET HAVING A FREE EDGE EXTENDING BEYOND SAID FREE EDGE OF SAID RELATIVELY SHORT SHEET.

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