US3027695A

US3027695A - Method and apparatus for packaging

Info

Publication number: US3027695A
Application number: US85545A
Authority: US
Inventors: William C Leasure
Original assignee: Mira Pak Inc
Current assignee: MIRA-PAK MACHINERY Co Inc; Mira Pak Inc
Priority date: 1961-01-30
Filing date: 1961-01-30
Publication date: 1962-04-03
Anticipated expiration: 1979-04-03
Also published as: GB943574A

Description

April 3, 1962 w. c. LEASURE 3,027,695

METHOD AND APPARATUS FOR PACKAGING Filed Jan. 30, 1961 3 Sheets-Sheet l INVENTOR ATTORNEKS April 3, 1962 w. c. LEASURE 3,0 7,

METHOD AND APPARATUS FOR PACKAGING Filed Jan. 50, 1961 3 Sheets-Sheet 2 \l'zgfi- 6 [A \Y/ 9 i L7 J 14 16 1: ,75 L J =L J0 J6 17 9 m1 g g V INVENTOR W/AA/JM (LLMSI/RA'E,

BY (Z2691 ATTORNEY 5 April 3, 1962 w. c. LEASURE 3,027,695

METHOD AND APPARATUS FOR PACKAGING Filed Jan. 30, 1961 5 Sheets-Sheet 3 J4 16 :15 1 J. E T K T J 19 gr? INVENTOR BY rd ATTORNEYS ilnited States Patent 3,027,695 METHGD AND APPARATUS FOR PACKAGING William C. Leasure, Houston, Tex., assignor to Mira-Yak, Inc., l-liouston, Tex., a corporation ofTexas Filed rm. 39, 1961, Ser. No. 85,545 9 Claims. (Cl. 53-48) This invention relates to a method and apparatus for packaging and more particularly to a method and apparatus for forming packages from a flexible packaging material wherein the packaging material is preshaped in the sealing area to. insure a more secure uniform end seal, the packages being filled more uniformly and having a predetermined configuration. The present application is a continuation in part of copending application Serial Number 5916, filed February 1, 1960, for Method and Apparatus for Packaging, now Patent No. 2,969,627.

According to the above mentioned prior application a method and apparatus for packaging is provided wherein an external former which shapes strip material into tubular form is adapted to reciprocate with respect to the supporting frame. A pair of jaws which serve as sealing and severing means are provided and these jaws are constructed in a manner generally similar to that described in the prior art. The pair of jaws are mounted so that they reciprocate into and out of engagement with the packaging material to form the end seals and separate the individual packages. The cycle of operation of such an apparatus is as follows:

Commencing with the former in its lowermost position and the jaws in engagement to complete the end seals, the product is dispensed into the package, the former moves upwardly, the jaws are released when the bag length has been made and the former continues its upward movement with the package, top unsealed, the former then reverses and then moves downwardly passing the filled package through the opening between the jaws and the jaws are re-engaged to form the top seal of the package and the bottom seal of the succeeding package and to sever the completed package from the strip material.

It has been found desirable to provide means for positioning the product within the bag and to shape the bag uniformly and in addition to provide for sealing the packaging material when the material is in a preshaped flattened condition to produce a uniform seal. The present invention achieves these objectives by providing a combination or" stripper plates and styling plates which are mounted on reciprocating jaw carriersin such a manner that these elements perform the functions set forth above. The stripper plates are mounted on the reciprocating jaw carriers for the sealing jaws and are adapted to be brought together in closely spaced relation during movement of the packaging material. The stripper plates may be moved to their operative position as the former moves downwardly or as the former moves upwardly but in either case there is a gradual transition in the packaging material from the tubular to a flattened condition as the stripper plates are brought together. As the former moves upwardly and the point in the packaging material which is to form an end seal p'asses between the sealing jaws, thesealing jaws are brought together to seal the packaging material and sever the individual packages. Because of the prior action of the stripper plates the area in which the seal is to be effected is in a flattened condition to permit the formation of a smooth even air tight seal. The stripper plates also perform the function of forcing the product into the package to provide a cleared area for seal formation, if product happen to, be disposed in the sealing area.

Thus, according to the present'invention the jaw carriers are moved to a position in which the stripper plates are operative and subsequently the jaws are moved to a position in which the sealing jaws are operative. This, in effect, comprises a two stage sealing operation, the first stage serving to prepare the packaging material for sealing by smoothing and flattening the surface of the packaging material and the second stage comprising the actual sealing operation.

In addition to the foregoing there is provided a pair of spring biased package engaging plates termed styling plates which may be mounted on the stripper plates and are moved to operative position at the same time as the stripper plates. The styling plates engage the package being formed, force the air therefrom the shape the contour of the package to any desired configuration.

An object of the present invention is to provide a method and apparatus for maintaining uniform end seals in known packaging equipments by preshaping the packaging material in the sealing area prior toscaling.

Another object of the present invention is to provide a method and apparatus for insuring that all of the product fed to an individual package is within that particular package and clear Of the sealing area.

Still another object of the present invention is to provide means for forcing the air out of a formed package and to shape the package into the particular desired configuration.

Other objects and many of the attendant advantages of the present invention will become more readily ap parent upon consideration of the following detailed specification in connection with the "accompanying drawings wherein: FIGS. 1 to 6, inclusive, are diagrammatic drawings showing the sequence of operation of the present invention in connection with the packaging of a product such as, for example, potato chips.

Referring now more specifically to the drawings wherein like numerals indicate like parts throughout the several views there is shown at 1 in FIG. 1 a roll of packaging material which is of a type which may be sealed and which is drawn off the roll and is passed over a series of rollers 2, 3, 4, and 5 which are rotatable in a stationary frame. There is provided a roller 6 which is weighted or spring biased and is slidable in the frame so as to create the desired amount of tension in the strip material. The strip of packaging material passes under a roller 7 which is movable with the former ii as will become more apparent hereinafter.

The former 3 is adapted to shape the strip material into tubular form and this former may be constructed as described in my prior Patent Number 2,899,875, issued August 18, 1959. This former is disposed entirely externall of the strip material so that the product may be fed into the open upper end of the former.

As shown in FIG. 1 there are provided a pair of hydraulic cylinders 9 ard 16 within which are mounted

rod assemblies

11 and 12, respectively. Rod if has mounted on the outer end thereof a jaw carrier mounting a sealing jaw 13 and rod 12 has a jaw carrier comprising a secondary hydraulic cylinder 14 mounted on its outer end. Within cylinder 14 is a rod assembly 15 having sealing jaw 16 mounted thereon. Sealing jaws l3 and 16 have heating elements disposed therein which are adapted to seal packaging material and in addition the jaws provided with severing means adjacent the midpoint thereof. The operation and construction of such jaws is well known in the art and is shown, for example, in Patent Number 1,986,422. It is to be understood, however, that there are numerous types of sealing jaws which would be suitable for this particular purpose and the specific construction of these jaws form no part of the present invention.

Mounted on the jaw carrier mounting jaw 13 is a stripper plate 17 and mounted upon the jaw carrier comprising secondary hydraulic cylinder 14 is a stripper plate 18. The stripper plates are so mounted that the outer ends thereof are spaced apart from .025 to .035" when the jaw carriers are in the FIG. 1 position and when a relatively thin packaging film is used. Thicker packaging materials will require wider spacing. The stripper plates are of a width substantially the same as the width of the sealing jaws so that they extend across the entire outer face of the packaging material.

A pair of

arms

19 and 2 are pivotally mounted on stripper plates 17 and 18, respectively. These arms are spring biased to the position shown in FIG. 2 and are adapted, when the stripper plates are brought together, to engage a formed package and press against the outer faces of the package in the manner shown in FIG. 1. The

arms

19 and 20 are shown as having curled outer ends but it is readily apparent that these arms may be shaped in any desired configuration so as to achieve any particular desired package shape.

The operation of the presently disclosed invention is as follows. With the parts in the position shown in FIG. 1 the

sealing jaws

13 and 16 are in engagement with the packaging material so as to form the top seal of package 21 and the bottom seal of package 22. The severing means within the jaws cuts the package 21 free from the strip of packaging material so that when the

jaws

13 and 16 are moved outwardly the package 21 is freed. The former 8 commences its downward movement after the jaws have separated as shown in FIG. 2 until the former 8 has reached the lowermost position thereof as shown in FIG. 3. It can be seen that as the former moves downwardly packaging material will be pulled from the roll 1 and transferred to a position between the rollers 5 and 7. It is also to be noted that as the former moves downwardly, tensioning roller 6 moves upwardly. The former moves downwardly approximately two bag lengths although the specific distance moved by the former 8 may be varied to suit any particular operational requirement.

In FIG. 4 it can be seen that the rod assemblies 11 and 12 Within

cylinders

9 and 10 have been moved towards each other to their limit of movement provided by stops (not shown). This movement may commence prior to the time the former has reached the lowermost position of movement or alternatively as the former is moving upwardly. In either case the packaging material is moving past the stripper plates 17 and 18 as the rod assemblies 11 and 12 are moved to bring the

stripper plates

17 and 13 into operative position. As the stripper plates move inwardly there is a gradual transition of the packaging material from the substantially tubular shape to a flattened shape. In this position the sealing jaw 13 is disposed immediately adjacent the packaging film where as the sealing jaw 16 is spaced from the film by reason of the fact that the piston within secondary cylinder 14 is in a retracted position. The stripper plates 17 and 18 are now in their operative position and are spaced apart -a comparatively small distance such as .025 so that the packaging film between the stripper plates will be flattened and smoothed prior to forming the top package seal. It can also be seen that the arms 1% and 20 have been brought into engagement with the packaging film.

The former 8 now commences its upward movement as shown in FIG. 5 and a portion of the packaging film which was brought from the roll 1 to produce additional length of film between rollers 5 and 7 is taken up by the lowering of tensioning roller 6 between rollers 3 and 4. The stripper plates 17 and 18 engagethe packaging material and serve to flatten the film and to force any of the product down into the package 22 to provide a cleared sealing area. The

plates

19 and 20 engage the upper portion or the envelope which is to form the package 22 and tend to force the air from the package and to shape the upper end of the package into a configuration conforming to the shape of the plates.

When the former has moved upwardly a distance equal to the distance moved downwardly in excess of one package length so that the point in the packaging film which is to comprise the upper end of the package 22 is adjacent the sealing jaws, the sealing jaw 16 is urged to extended position by actuation of the piston within cylinder 14. It can be appreciated that since the stripping plates 17 and 18 are mounted on the jaw carrier mounting sealing jaw 13 and the jaw carrier comprising cylinder 14, respec tively, the position of stripper plates is not changed. In FIG. 6 the sealing

jaws

13 and 16 are shown in engaged position so as to form the top seal of the package 22 and the bottom seal of the next adjacent package. The former continues its upward movement and the product is fed into the open upper end of the former 8 during the additional travel upward of the former. It can also be seen that since the former is moving upwardly and the sealing

jaws

13 and 16 are firmly gripping the packaging film, film will be transferred from the position between rollers 5 and 7 to a position on the former 8 and into a tubular shape beneath the former. The parts are then returned to the position shown in FIG. 1 with the former at the upper end of the movement and the sealing jaws and jaw carriers ready to move to the disengaged position.

It can be seen that the stripper plates 17 and 18 flatten the packaging material to prevent the formation of tucks or overlap portions in the seal. Thus, the stripper plates serve the function of presenting a flat packaging surface for sealing by the sealing jaws. In addition, it can readily be seen that the stripper plates perform the additional function of forcing the product into the package. Simultaneously the pivoted

arms

19 and 20 force the air from the package because of their spring biasing. In addition these arms perform the function of shaping the upper end of the package. In this manner uniform packaging is assured. Due to the fact that the former is moving downwardly as the stripper plates are brought together, the stripper plates contact the pack-aging film while it is in a tubular form and there is a gradual transition from the tubular shape to a flat shape as the stripper plates move together.

While the stripper plates and package engaging styling plates have been shown as used on a packaging apparatus having a movable former, it is apparent that these devices find utility in connection with the more conventional type of packagingapparatus wherein a stationary former is employed and the sealing and severing jaws reciprocate vertically as well as transversely. The modification of such apparatus to include the structures disclosed herein will be readily apparent to those skilled in the art.

Obviously many modifications and variations of the present invention are possible in light of the above teachings.

What is claimed as new and desired to be secured by Letters Patent is:

l. A method of packaging comprising the steps of passing strip packaging material over a former to form the material into a substantially tubular shape, forming the bottom seal of one package and the top seal of an adjacent package with a pair of sealing jaws, filling said one package with product, passing the packaging material between the sealing jaws in one direction for one package length and an additional predetermined length, engaging the packaging material with stripper and styling plates to flatten the packaging material prior to scaling, and force product into the package, force air from the package and shape the package while moving the packaging material in the opposite direction for the additional predetermined length and subsequently forming the top seal of the package.

2. Packaging appartaus comprising, a former for shaping packaging material into substantially tubular form, means for reciprocating said former, a pair of jaws for sealing and severing said packaging material into individual packages, stripper plates for flattening the packaging material in the area to be sealed, means for bringing said stripper plates into and out of closely spaced relationship with respect to the packaging material and means for bringing said jaws into and out of engagement with the packaging material, said stripper plates being disposed in closely spaced relationship during at least a portion of the reciprocating cycle of the former.

3. Packaging apparatus according to claim 2 wherein said stripper and jaw operating means comprises hydraulic mechanism, one of said jaws and one of said stripper plates being mounted on a first hydraulically actuated red, the other of said stripper plates and a secondary hydraulic mechanism being mounted on a second hydraulically actuated rod, the other of said jaws being mounted on a rod actuated by said secondary hydraulic mechanism.

4. A method of packaging comprising the steps of forming strip packaging material into tubular shape, sealing the bottom of a package by means of a pair of sealing jaws, filling the package with product and releasing the sealing jaws, relatively moving the sealing jaws and packaging material with respect to each other along the longitudinal axis of the tubular formed packaging material in a first direction for a distance greater than one package length, engaging the packaging material with stripper plates to flatten the tubular formed packaging material, relatively moving the sealing jaws and packaging material along the longitudinal axis of the tubular formed packaging material in a direction opposite to the first direction for a distance equivalent to the distance greater than one package length moved in the first direction towards the package to be formed to force product into the package and engaging the sealing jaws to form the top seal of the package in the area of the packaging material initially flattened by the stripper plates.

5. A method according to claim 4 including the step of simultaneously engaging the packaging material with stripper plates and pivoted spring biased styling plates, the styling plates engaging the sides of the package being formed.

6. A method of packaging including a two stage stripping process comprising the steps of forming strip packaging material into tubular shape, sealing the bottom of a package with a pair of sealing jaws, relatively moving the sealing jaws and packaging material with respect to each other along the longitudinal axis of the tubular formed packaging material in a first direction for a distance greater than one package length, moving a pair of stripper plates in a plane perpendicular to the longitudinal axis of the tubular formed packaging material to a closely spaced relationship to engage and flatten the packaging material as the first stripping stage, relatively moving the packaging material and stripper plates in a direction parallel to the longitudinal axis of the packaging material while maintaining the stripper plates in said closely spaced relationship in engagement with the packaging material as the second stripping stage, the second stripping stage moving the packaging material and sealing jaws relative to each other in a direction towards the package to be formed for the distance moved in the first direction greater than one package length and engaging the sealing jaws to form the top seal of the package in the area of the packaging material initially flattened by the stripper plates.

7. A method of packaging including a two stage stripping process comprising the steps of forming strip packaging material into tubular shape, sealing the bottom of a package with a pair of sealing jaws and filling the package with product, relatively moving the sealing jaws and packaging material with respect to each other along the longitudinal axis of the tubular formed packaging material in a first direction for a distance greater than one package length, linearly moving a pair of stripper plates in a plane perpendicular to the longitudinal axis of the tubular formed packaging material from an inoperative position to a single operative position where the strippers are in a closely spaced relationship to engage and flatten the packaging material as the first stripping stage, relatively moving the packaging material and stripper plates in a direction parallel to the longitudinal axis of the packaging material while maintaining the stripper plates in said operative position in engagement with the packaging material as the second stripping stage, the second stripping stage moving the packaging material and sealing jaws relative to each other in a direction towards the package to be formed for the distance moved in the first direction greater than one package length and engaging the sealing jaws to form the top seal of the package in the area of the packaging material initially flattened by the stripper plates.

8. A method of packaging including a two stage stripping process comprising the steps of forming strip packaging material into tubular shape, sealing the bottom of a package with a pair of sealing jaws and filling the package with product, relatively moving the sealing jaws having stripper plates connected thereto and packaging material with respect to each other along the longitudinal axis of the tubular formed packaging material in a first direction for a distance greater than one package length, linearly moving the stripper plates in a plane perpendicular to the longitudinal axis of the tubular formed packaging material from an inoperative position to a single operative position where the strippers are in a closely spaced relationship to engage and flatten the packaging material as the first stripping stage, relatively moving the packaging material and sealing jaws with the stripper plates connected thereto along the longitudinal axis of the packaging material while maintaining the stripper plates said operative position in engagement with the packaging material as the second stripping stage, the second stripping stage moving the packaging material and sealing jaws relative to each other in a direction towards the package to be formed for the distance moved in the first direction greater than one package length and engaging the sealing jaws to form the top seal of the package in the area of the packaging material initially flattened by the stripper plates.

9. A method of packaging comprising the steps of forming strips packaging material into tubular shape, sealing the bottom of a package with a pair of sealing jaws and simultaneously filling the package with product, relatively moving the sealing jaws and packaging material with respect to each other along the longitudinal axis of the tubular formed packaging material in a first direction for a distance greater than one package length, moving a pair of pivoted styling plates to a position to engage the packaging material to shape the package and remove air from the package, relatively moving the packaging material and styling plates in a direction parallel to the longitudinal axis of the packaging material while maintaining the styling plates in engagement with the packaging material, said last named movement moving the packaging material and sealing jaws relative to each other in a direction towards the package to be formed for the distance moved in a first direction greater than one package length and engaging the sealing jaws to form the top seal of the package.

References Cited in the file of this patent UNITED STATES PATENTS 2,113,636 Vogt Apr. 12, 1938 2,915,866 Bartlo Dec. 8, 1959 2,960,808 Pike Nov. 22, 1960 2,969,627 Leasure Jan. 31, 1961