US3150472A - Method and apparatus for vacuum packaging - Google Patents

Description

Sept. 29, 1964 MOORE METHOD AND APPARATUS FOR VACUUM PACKAGING Filed Feb. 26, 1962 INVENTOR ATTORNEY United States Patent 3,150,472 METHOD AND APPARATUS FOR VACUUM PACKAGING George Arlington Moore, New York, N.Y. (910 Lake Shore Drive, Chicago, Ill.) Filed Feb. 26, 1962, Ser. No. 175,462 9 Claims. (Cl. 53-22) This invention relates to a novel and improved air evacuator device for the packaging of food-stuffs and other commodities under vacuum, and more particularly it pertains to the novel means and method employed in the process of air evacuating product filled bag-like containers made of flexible sheet material such as thermoplastic film or combinations thereof, and whereby upon open registry of the container with the device and actuating its air-suction arrangements a high vacuum is Instantly developed within the body of the container which causes the pressure of the atmosphere to highly compress the product filled container into closed registry upon the device in vacuum sealed relationship to complete the container evacuation. Then by apparatus actuating means the container is permanently heat-sealed in hermetic seam forming relationship.

In my prior Patents No. 2,863,266 for Air Extractor Device, and No. 2,863,267 for Air Extractor and Sealing Device, both having issued on December 9, 1958, there is disclosed novel means and methods for air evacuating packaged products in containers. In the operations of these devices good results were obtained when air evacuating containers that were fabricated of semi-rigid sheet laminated materials such as combinations of sheet aluminum, paper and plastic film. However, when experimenting with pouch type containers formed of flexibly soft plastic film sheet material the end results obtained when evacuating them was not entirely satisfactory. The fault was discovered to be in the non-resistance characteristics of the limp soft plastic film of the pouch having a tendency to foul the air suction mouth of the device during the stage of evacuating the product filled pouch. 'It is therefore a prime object of the present invention to provide an improved air evacuator device having unique means for evacuating the above described pouch containers under a high vacuum and avoid any fouling of the air suction mouth of the device by the limp soft plastic film'material of the product filled pouch container.

Another object of the invention is to provide the air evacuator device with air suction openings arranged in transverse relationship coupled with conjunctive means for keeping the mouth of the product filled container in open registry with the device at the moment of drawing the high vacuum in the container, whereby the co-acting pressure of the atmosphere compresses the walls of the container to a point where the mouth closes upon air suction openings of the device in vacuum sealed relationships to complete the air evacuation of the container, their by actuating means heat sealing the evacuated product filled container in hermetic seam forming relationship.

A further obiect of the invention is to provide the air evacuator device with apparatus means to be added when desired, for clamping the mouth of the air evacuated container to maintain its sealed registry upon the device at the moment of actuating a charge of inert gas through the device and into the evacuated container, then heat sealing the gassed container in hermetic seam forming relationship.

th'er objects and features of the invention will appear more fully hereinafter from the following detailed description when considered in connection with the accompanying drawings. t is expressly understood, however, that the drawings are intended only for the purposes of illustration, and are not to be taken as a definition of the ice limits of the invention, reference being had for this purpose to the appended claims.

In the drawings, wherein similar reference characters refer to similar parts throughout the several views;

FIG. 1 is a view in side elevation of the air evacuator device shown in registry with a container pouch partly broken away, and including fragmentary portions of the pouch tracking bars;

FIG. 2 is an end view of the device taken in cross section vertically along the line 2-2 in FIG. 1, and showing the open mouth registry of the container, partly in cross section, in relation to the device, and further showing the relative position thereto of heat sealing bars indicated by fragment parts thereof shown in cross section;

FIG. 3 is a bottom plan view of the device and tracking bars of FIG. 1 without the container and showing the air suction mouth of the device in conjunctive relationship with open pressure resisting member parts;

FIG. 4 is another similar View of the device taken longitudinally along the line 4-4 in FIG. 2 eliminating the container, and showing other air suction holes in the device in relation to the pressure resisting members;

FIG. 5 is a fragmentary end View of the pouch container showing its mouth end trough-like marginal lips for mouth registry with the device;

FIG. 6 is a fragmentary View in side elevation of the pouch container and showing the manner in which the marginal lips are formed at the mouth thereof;

FIG. 7 is a fragmentary View in end elevation showing the open mouth registry of the pouch container over the air suction mouth of the device and wherein is shown the relationship of the V-shaped crotch of the pouch with respect to the end edge of the device;

FIG. 8 is another similar view partly in cross section showing the mouth registry as it appears after the pouch container has been air evacuated;

FIG. 9 is a view comparable to FIG. 1 and showing the evacuated pouch container in relation to the heat sealing bars that are shown in dot and dash lines extending across the neck portion thereof, and further showing a fragmentary'part of another container in mouth registry with the tracking bar ready for registry with the device;

FIG. 10 is an end view partly in cross section showing the device in vacuum sealed registery with the air evacuated product filled pouch container in the stage of being heat sealed to complete the vacuum packaging of the product, and

FIG. 11 is a fragmentary end View of the device-and evacuated container showing its mouth clamped relationship upon the device when it is desired to charge the air evacuated container with inert gas prior to heat sealing the container as shown in FIG. 10.

The present invention is particularly directed to a unique means and method for drawing substantially an instant vacuum in product packed containers especially those formed of soft flexible plastic film materials, and the vacuum being initially drawn at a moment during the registry of the open mouth of the container with the air evacuating device, and of regulating the closing moment thereof upon the device in vacuum sealed registry for completing the evacuation of the container. Then heat sealing the container in hermetic seam forming relationship. The extent of the vacuum drawn in the container may be of a measurement in any range desired up to 29.0 inches of mercury Hg depending upon the size of the vacuum pump air displacement capacity that may be selected for the particular duty requirements. At 29.0 inches of mercury vacuum the compression uponthe walls of the container caused by the effects of the coacting pressure of the atmosphere thereupon is 14.5 lbs.

- per square inch which may. be correlated to actuate the regulated registry closing moment of the container mouth 3 the device in temporary vacuum sealed relationship which substantially completes the evacuation.

To this end, pouch or bag-like containers made of suitable impermeable thermoplastic sheet material are to be formed having marginally opposed flaring lips at the open mouth thereof to be utilized for making connection with'the air evacuator device. After filling the container with its intended product to be vacuum packed, the main body is conveyed by suitable supporting means while the lips thereof are guided over a central bar aligned with the device and to bring the mouth of the container into a regulated open mouth registry with the air suction mouth of the air evacuator and the lips in openly spaced relation with respect to the other air suction holes through opposed sides of the evacuator. Upon actuating a normally closed valvular control vacuum source system connected with the evacuator device, the air suction through the device instantly draws a high vacuum in the container causing the atmospheric pressure to co-act and simultaneously compress the walls of the container to a pressure that is correlated to actuate the regulated registry and close the mouth of the container into vacuum sealed. registry upon the evacuating device. Then by its apparatus means provided, actuating the heat sealing of the evacuated container in hermetic seam forming relationship. In a particular form taken of the apparatus, the evacuator and sealing bars embodied therein may be extended in length to handle product filled containers two or more at a time.

Referring more particularly to FIGS. 1, 2 and 3 of the drawings, the present invention is illustrated therein as including a main body part of the air evacuator 4 that is somewhat similar in construction to the one disclosed in my prior patents hereinbefore mentioned, and which consists of an elongated rectangular shape body having a longitudinal V-shape bottom end portion with an elongated air-suction open slot 5 passing upwardly and through the center of a major part of the common end edge 6 of the V-shape side wall portions 7. A series of additional airsuction holes 8 of combined intake area that is considerably less than the intake area of the airsuction slot 5 are provided transversely through each inwardly sloped side wall 7 in openly spaced relationship and upwardly of the end edge 6. The air- suction openings 5 and 8 communicate with an enclosed cavity space ll provided within the body of the device, the cavity having an outlet 18 for hook-up connection with a valvular controlled conduit line leading to a suitable vacuum pump. In addition to the air-suction openings described, the air evacuator body is provided with a pair of elongated like opposed spring active prongs 11 of bow shaped contour each with a straight end extension 12 that is securely fastened into the receptive aligning recesses 13 longitudinally extended in each sloping side wall 7 and between its'common end edge 6 and the series of airsuction holes 8 as illustrated in FIG. 1. The bow leg of each prong is spaced outwardly of a majority of the air-suction holes in the related side wall 7, and the unattached end 14 of the bow leg rests in normal position under spring pressure in the aligning recess 13 as illustrated in FIG. 3. These prongs may be made of any suitable material or metallic alloy having spring leaf characteristics, each prong being calibrated in thickness of material and open contour that will normally resist pressure when imposed thereupon for a purpose hereinafter to be described.

In the apparatus arrangements of the device 4 there is provided a central elongated bar 15 secured in alignment with the V-shape side wall surfaces 7 of the air evacuator body as illustrated in FIGS. 1 and 3, and to be used for guiding the open mouth of each container into registry with the device. Also included are a pair of opopsed heat sealing bars 16 indicated by fragmentary parts thereof in open position relative to the air evacuator body as illustrated in FIG. 2. These bars may be of the impulse heating type which may be provided in any bar length required up to 96 inches and with heat sealing actuating arrangements. In this respect, the air evacuator body of the device may also be provided in any length required to coincide with the particular linear length of the sealing bars and be arranged to have segregated air suction stations spaced in line for registry with each product filled container of a multiple in line group that may be brought into registry and be air evacuated and heat sealed in one cycle of operation. The apparatus can also be arranged to handle a large size bag containing for example, a relatively large size bulk unit of butchered meat product to be vacuum packed for wholesale distribution including export. The container 17 in pouch form used for illustration in FIGS. 5 and 6 is provided with a pair of opposed open lips 18 at the mouth end thereof. These marginal free flaring lips extending across the pouch are formed by stopping off the side seams 19 of the pouch body to also form the crotch end 29 spaced inwardly of the top end edges of the lips thereby providing the open mouth of the pouch with means for registry engagement with the air evacuator device as illustrated in FIGS. 1, 2 and 7. After filling the pouch with its intended product the lips thereof are directed into engagement with the central bar 15 of the device over which these lips are spread to guide them during the movement of the pouch into registry position with the air evacuator body, whereby the mouth of the pouch is spread open by contact with the inner disposed open contoured prongs 11 between the crotch ends 20 of the pouch which are in register with the longitudinal end edge 6 of the air evacuator body as shown in FIGS. 1, 2 and 7. It is to be noted that the air suction passages in their transverse relationship disposed through the longitudinal V-shape end of the air evacuator body are projected well into the open mouth of the registered pouch between the opposite end closing crotches 20 thereof as illustrated in FIGS. 1 and 2. The extent of the mouth opening is governed by the contoured prongs A in spacing a portion of the opposite side walls of the pouch away from a major portion of the lesser air suction passages 8, this correlation is illustrated in FIG. 4 in view of FIG. 2.

The operating cycle of exhausting the gaseous fluids from the product filled container is initiated by opening a control valve, suitably actuated, that is provided in the air suction pipe line of the system to the device 4, whereby the air suction draft through the larger open slot 5 and series of lesser open holes 8 in the device instantly develops a high vacuum in the body of the container augmented by the co-acting pressure of atmosphere that simultaneously compresses the walls of the container thereby accelerating the exhaust of the gaseous fiuids from the container. In so doing, the mounting pressure exerted upon the side walls and marginal lips 18 at the mouth thereof overpowers the calibrated pressure resisting prongs 11 therein causing their resistance to yield under the pressure that presses the opposing lips each upon each side walls '7 thereby closing the air suction holes 8 which tightly seals the mouth of the container upon the device under vacuum in the relationship shown in FIG. 8. In more descriptive detail by way of example, the initial vacuum developed in the container body may range up to approximately 28 inches of mercury Hg whereby the coacting pressure of atmosphere simultaneously compresses the walls of the container up to a pressure of 14 lbs. per square inch. The mouth supporting prongs 11 (FIGS. 2 and 4) being calibrated to resist imposing pressure up to slightly less than 14 lbs. per square inch will then yield by this pressure that is imposed upon the marginal lips 13 at the mouth of the container and pressing them upon the side walls 7 and in the same instant compressing each prong flatly into its receptive recess 13 in these side walls. At this instance the lips 18 and crotch ends 29 at the mouth of the container are temporarily vacuum sealed to the device. At this stage of the operation the heat sealing bars 16 of the apparatus are actuated by suitable means that heat seals the closed neck 21 of the evacuated container in hermetic seam forming relationship in the manner illustrated in FIGS. 9 and 10. The sealing bars are then retracted as the control valve in the air suction line is actuated to close shutting off the air suction to the device that releases the container for removal therefrom and for the next container registry.

The invention contemplates a further adaptation having means provided for replacing the air that is extracted from the product filled containers with an inert gas such as carbon dioxide or nitrogen for gas packaging certain particular grades of food-stuffs. The adapted means may include a similar valvular control system that is disclosed in my prior Patent No. 2,863,267 hereinbefore mentioned. In addition thereto the air evacuator of the present invention may be equipped with a pair of opposing elongated blades 22 to be actuated for mechanically clamping the vacuum sealed lips 18 upon the air evacuator prior to the admission of gas into the evacuated container. The bite of the clamp by the thin blades may be augmented by providing an offset groove 23 that will extend longitudinally across each of the sloping side walls 7 of the air evacuator as illustrated in the end view FIG. 11. The blades 22 may be mounted on rocker arms pivoted on the side walls of the device 4 and timed for in and out movement actuated by the cycle timed motion given to the sealing bars 16 or by other means that may be arranged in the working phases of the apparatus. In this respect the clamp of the lips 18 of the evacuated container takes place at a moment when the heat sealing bars 16 have moved into a progressive position short of making contact with the neck margin 21 of the evacuated container as illustrated in FIG. 11. At this instant the by-pass valvular control system is actuated to shut off the air suction line to the air evacuator and in short cycle timing actuation open and close the by-pass valve that releases a predetermined limited amount of gas from its pressure controlled tank supply to pass through the air evacuator and into the evacuated container which is then instantly heat sealed in the manner illustrated in FIG. 10. In carrying out the above described method of gas packaging of commodities the inert gas consumption per unit packaged affords marked economy as compared with the conventional types of apparatus that utilize a vacuum chamber in which the encased evacuated container is gassed and sealed, the residual gas left in the chamber is then exhausted.

While the present invention has been illustrated and described in essential detail, it is to be understood, however, by those skilled in the art, that various changes may be made therein without departing from the scope and spirit of the invention, reference being had for this purpose to the appended claims for a definition of the limits of the invention.

What is claimed is: V

1. A device for air evacuating product filled containers having its openmouth adapted with means for registry with the device, which includes an elongated body mem-,

her having an inner cavity space connected with a source of vacuum and further communicating with a major size intake air suction passage provided through a central part of the longitudinal corner end of the opposite side Walls of said body and including a series of other minor size intake air suction passages disposed transversely through each of said side walls, each of two opposed spring active contoured prongs being provided and secured at one end thereof upon each of said sidewalls and disposed longitudinally between said first and second mentioned air suction passages, the contoured part of the prong being spaced outwardly from the surface plane of said side wall in the area of a limited number of said series of minor air suction passages therein, whereby upon registering the open mouth of the container over said prongs and opposite side walls of the body member, upon opening its source of vacuum the air suction through all of its passages instantly developes a high vacuum in the container causing the pressure of the atmosphere to coact and simultaneously highly compress the Walls of the container at a point of pressure that causes said prongs to yield inwardly thereby closing the mouth of the container upon the device in temporary vacuum sealed relationship effected by said second mentioned air suction passages, and by heat sealing means provided, sealing the evacuated container in hermetic seam forming relationship.

2. A device according to claim 1 wherein each surface of said side Walls having the second mentioned series of minor air suction passages being provided with an elongated receptive recess to receive each prong of said pair when being compressed by the effects of said pressure imposed upon the walls at said mouth of the container and closing said mouth upon the compressed prongs and side walls of the device in temporary vacuum sealed relationship until the evacuated container is heat sealed permanently.

3. The apparatus of claim 1 including a pair of opposed actuating container mouth clamping means dis posed outwardly from and parallel to each line of said series of minor air suction passages,

said clamping means being adapted to mechanically clamp said mouth of the evacuated container against said elongated body thereby sealing said mouth to said elongated body independently of the vacuum seal and permitting a recharge of said container by a gas through said air passages prior to heat sealing said container.

4. The method of air evacuating product-filled containers characterized as having a pair of opposed side wall flaring lips at the mouth thereof adapted for registering with an air evacuator device which has co-acting air passages connectable with a source of vacuum, comprising the steps of;

(a) spreading said flaring lips apart,

(b) directing said spread-apart lips over a pair of opposed openly-spaced pressure resisting flexible mouth support members with the base of said lips in register with said air evacuator device,

(c) opening said vacuum source to said device, the air suction effect thereof instantly developing a high vacuum in said container causing the atmospheric pressure to compress said container walls and to compress said lips causing said mouth support members to yield and flatly register said lips in temporary vacuum sealed relationship upon selective air passages of coinciding wall portions of said device,

(d) completing the evacuation 'of said container.

(e) sealing said mouth of saidrevacuated container in hermetic seam forming relationship,

5. The method of air evacuating product-filled containers characterized as having a pair of opposed side wall flaring lips at the mouth thereof adapted for registery with the air evacuated device which has coacting air passages connectable with a source of vacuum and a source of inert gas under pressure, comprising the steps of;

(a) spreading said flaring lips apart,

(b) directing said spread-apart lips over a pair of opposed openly-spaced pressure resisting flexible mouth support members with the base of said lips in register with said air evacuator device,

(c) opening said vacuum source to said device, the air suction effect thereof instantly developing a high vacuum in said container causing the atmospheric pressure to compress said container walls and to compress said lips causing said mouth support members to yield and flatly register said lips v in temporaryvacuum sealed relationship upon selective air passages of coinciding wall portions of said device,

(d) completing the evacuation of said container.

() clamping said lips mechanically against said coinciding wall portions of said device sealing said lips independently of said vacuum sealing,

(1) closing off said vacuum source from said device at the same time as opening said source of inert gas to said device to charge said sealed container with said gas,

(g) sealing said mouth of said container in hermetic seam forming relationship.

6. In apparatus, an air suction device having a connection with a source of vacuum for evacuating the air contents in product filled containers characterized as being of the thermoplastic pouch or bag type, the open mouth of the container being elongated and adapted for initial registry with the opposite sides of the device and in openly spaced relationship thereto, the device comprising an elongated body having air suction means defining a series of co-acting air intake passages arranged through said body in transverse relationship, and including container mouth supporting pressure resistant means for maintaining said openly spaced relationship of said container mouth with said sides of the device, by said air suction means a high vacuum being developed in evacuating the container that causes the walls thereof to be compressed inwardly by the co-acting pressure effects of atmospheric pressure thereupon, whereby said compression reaches a point of pressure almost instantly that overcomes said pressure resistant means and closes the mouth of the container upon said opposite sides of the device, minor air suction coacting passages that are provided through said sides being the medium that temporarily seals said mouth to the device thereby completing the air evacuation of the product filled container etfected by the major air suction passage in the device, and by apparatus means the evacuated container being heat sealed in hermetic seam forming relationship.

7. The method of packaging food-stuffs under vacuum in containers formed of heat-scalable sheet material and having mouth registry means adapted for engaging with an air evacuating device connected with a source of vacuum comprising bringing the wall portions at the mouth of the container into open registry alignment over mouth spreading and supporting pressure resistant means correlated with coracting air intake suction means arranged in said air evacuating device, opening said source of vacuum to the device whereby its main air suction effects evacuated the container causing the pressure effects of the atmosphere to simultaneously co-act in compressing the walls thereof to an extent of pressure that causes said correlated resistant means to yield thereby closing the mouth of the container upon the coincident wall surfaces of the device, and by the co-acting effects of the minor air suction means provided sealing said mouth upon the device in temporary vacuum sealed relationship thereby completing the air evacuation of the container, and while vacuum sealed heat sealing the mouth of the evacuated container by actuated apparatus meansprovided and co-ordinated with the actuation of said device.

8. In apparatus, a unit device for air evacuating product filled containers characterized as having a pair of flaring lips at the open mouth thereof adapted for initial open registry with the device that is under a controlled source of vacuum, and having a main air suction passage of major space area disposed centrally through the longitudinal corner end of two opposed tapered side walls thereof, each of said side walls having a series of longitudinally aligned air suction passages totally of minor space area and being spaced upwardly from said corner end, the device including a pair of opposed elongated spring active members that are calibrated in contour, each being secured at one end thereof upon each of said side walls, the contoured leg of the member being extended longitudinally inbetween said corner end and said series of air suction passages and being spaced outwardly from a majority of said passages, whereby upon registering said lips of the product filled container over said calibrated members the mouth of the container is initially confined in open registry with the device and upon opening its source of vacuum thereto the air suction effects through said major passage creates a high vacuum in the container thereby causing the pressure of atmosphere to simultaneously compress the walls thereof, and in sequence causing said lips of the container to compress and flatten said mouth confining members and close said mouth of the container upon said series of minor air suction passages in vacuum sealed condition upon the device thereby substantially completing the air evacuation of the container during after which the closed mouth thereof being hermetically sealed by the apparatus means provided.

9. In apparatus for packaging products under vacuum comprising an air evacuator unit device having a main air suction channel opening and transversely thereto a series of adjacent secondary air suction holes disposed through each of two opposite side walls of said unit, and including a pair of opposed and elongated pressure opposing prongs each having one end thereof secured upon each of said side walls, the leg of the prong being offset in spaced relation to the surface of said wall and extended longitudinally inbetween said main air suction channel and secondary air suction holes, whereby upon registering the open mouth of the product filled package over said prongs of the air evacuator device and opening its source of vacuum thereto the air suction through said main channel generates a high vacuum in the package thereby causing the pressure of the atmosphere to simultaneously highly compress the Walls thereof during which the pressure of the atmosphere flattens said leg of the prongs closing the mouth of the package upon the side walls and over said series of air suction holes, thereby sealing said mouth to the air evacuator device in temporary vacuum sealed relationship thereby completing the air evacuation of the package, the mouth of the vacuated package while under said temporary vacuum sealed condition being permanent-sealed in hermetic seam forming relationship.

References Cited in the file of this patent UNITED STATES PATENTS 2,559,368 Pancratz July 3, 1951 2,863,266 Moore Dec. 9, 1958 2,875,070 Rockland et al. Feb. 24, 1959 UNITED STATES PATENT :OFFICE CERTIFICATE OF CORRECTION September 29, 1964 Patent No, $150,472

George Arlington Moore e above numbered patrror appears in th should read as tifiedv that e the said Letters Patent It is hereby car and that ent requiring correction corrected below.

line 72, after "m0uth insert to column Column 2. d d

- oppose 3, line 73, for "opopsed rea Signed and sealed this 16th day of March 1965.

(TASEAL) Attest:

EDWARD J. BRENNER ERNEST W. SWIDER Attesting Officer Commissioner of Patents

Claims (1)

1. 4. THE METHOD OF AIR EVACUATING PRODUCT-FILLED CONTAINERS CHARACTERIZED AS HAVING A PAIR OF OPPOSED SIDE WALL FLARING LIPS AT THE MOUTH THEREOF ADAPTED FOR REGISTERING WITH AN AIR EVACUATOR DEVICE WHICH HAS CO-ACTING AIR PASSAGES CONNECTABLE WITH A SOURCE OF VACUUM, COMPRISING THE STEPS OF; (A) SPREADING SAID FLARING LIPS APART, (B) DIRECTING SAID SPREAD-APART LIPS OVER A PAIR OF OPPOSED OPENLY-SPACED PRESSURE RESISTING FLEXIBLE MOUTH SUPPORT MEMBERS WITH THE BASE OF SAID LIPS IN REGISTER WITH SAID AIR EVACUATOR DEVICE, (C) OPENING SAID VACUUM SOURCE TO SAID DEVICE, THE AIR SUCTION EFFECT THEREOF INSTANTLY DEVELOPING A HIGH VACUUM IN SAID CONTAINER CAUSING THE ATMOSPHERIC PRESSURE TO COMPRESS SAID CONTAINER WALLS AND TO COMPRESS SAID LIPS CAUSING SAID MOUTH SUPPORT MEMBERS TO YIELD AND FLATLY REGISTER SAID LIPS IN TEMPORARY VACUUM SEALED RELATIONSHIP UPON SELECTIVE AIR PASSAGES OF COINCIDING WALL PORTIONS OF SAID DEVICE, (D) COMPLETING THE EVACUATION OF SAID CONTAINER. (E) SEALING SAID MOUTH OF SAID EVACUATED CONTAINER IN HERMETIC SEAM FORMING RELATIONSHIP.

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