US3861113A

US3861113A - Packaging apparatus and method

Info

Publication number: US3861113A
Application number: US374902A
Authority: US
Inventors: H Hampton Loughry
Original assignee: Automated Packaging Systems Inc
Current assignee: Automated Packaging Systems Inc
Priority date: 1973-06-29
Filing date: 1973-06-29
Publication date: 1975-01-21
Anticipated expiration: 1992-01-21

Abstract

A packaging system utilizing a novel pressure pad structure to compress a flexible wall of an open loaded container to conform the wall to the general shape of container contents. A plurality of resilient, independently collapsible elements are carried by base structure and establish a highly resilient pressure pad. In the preferred embodment, the elements are tubular and have an annular lip formed near one end region. The elements are supported by clamping the lips between a pair of plates. The supporting ends of the elements are open to admit and discharge air. The distal ends are closed by integrally formed curved end walls. The pressure pad is preferably carried by one of two relatively movable closure members of a packaging machine and operates to deflate loaded packages before they are fully closed by the closure members.

Description

United States Patent 191 Loughry Jan. 21, 1975 PACKAGING APPARATUS AND METHOD [75] Inventor: H. Hampton Loughry, Aurora, Ohio [73] Assignee: Automated Packaging Systems, Inc.,

Twinsburg, Ohio [22] Filed: June 29, 1973 [21] Appl. No.: 374,902

[52] US. Cl 53/22 B, 53/112 B [51] Int. Cl B6Sb 31/00 [58] Field of Search 53/22 B, 112 B, 24, 124 A [56] References Cited UNITED STATES PATENTS 2,496,609 2/1950 Antwerpen 53/124 A X 3,325,845 6/1967 Sawkiw 300/21 X 3,471,990 10/1969 Bonuchi et al. 53/22 B Primary ExaminerTravis S. McGehee Attorney, Agent, or Firm-Watts, Hoffman, Fisher & Heinke Co.

[57] ABSTRACT A packaging system utilizing a novel pressure pad structure to compress a flexible wall of an open loaded container to conform the wall to the general shape of container contents. A plurality of resilient, independently collapsible elements are carried by base structure and establish a highly resilient pressure pad. In the preferred embodment, the elements are tubular and have an annular lip formed near one end region. The elements are supported by clamping the lips between a pair of plates. The supporting ends of the elements are open to admit and discharge air. The distal ends are closed by integrally formed curved end walls. The pressure pad is preferably carried by one of two relatively movable closure members of a packaging machine and operates to deflate loaded packages before they are fully closed by the closure members.

17 Claims, 3 Drawing Figures PACKAGING APPARATUS AND METHOD CROSS REFERENCE TO RELATED PATENTS PACKAGING METHOD AND APPARATUS, Ser. No. 336,560 filed Feb. 28, 1973 as a continuation-inpart of application Ser. No. 139,453, filed May 3, 1971, entitled PACKAGING METHOD AND APPARATUS, hereinafter the Machine Patents.

FLEXIBLE CONTAINER STRIPS, US. Pat. No. 3,254,828 issued June 7, 1966 to Hershey Lerner. This patent will be referred to as the Article Patent.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to packaging and more particularly to a packaging apparatus including an improved resilient pressure pad assembly for deflatingloaded bag-like containers.

2. Prior Art The Article Patent describes a chain of interconnected containers in the form of bags. The containers are each open on one face. The other face of each container is connected to a contiguous bag along a preformed line of weakness.

The Machine Patents disclose packaging apparatuses which feed such a web of bag like containers to a loading station. Each container is then sequentially opened, loaded, closed, sealed and severed from the web. Container closure is effected by a pair of relatively movable closure members which engage the open end region of the container bringing opposite faces of the container together. The closure is then secured, typically by heat sealing the faces together.

In some packaging applications, it is desirable to confine a quantity of air in the sealed containers to prevent the contents from being crushed or damaged during shipment. In other packaging applications, it is desirable to deflate the containers before they are sealed to minimize the volume of sealed containers. While the apparatuses of the Machine Patent are well adapted to confine a quantity of air in containers as they are closed and sealed, these apparatuses do not address the problem of deflating containers prior to closure.

Pressure pads such as sponge rubber rolls are known and have been used in some applications to deflate loaded containers. In many applications such pads are insufficiently resilient to deflate a container fully. Ideally, the container can be deflated by conforming loaded container regions to the general shape of the container contents, and by collapsing unloaded container regions.

Known pressure pads are not well adapted to effect such a deflating action unless they have pressure surfaces specially configured to the deflated shape of the loaded container. Specially configured pressure pads are usually relatively expensive and have little versatility for use with different size containers or different shaped products in the containers. Preshaped pressure pads'provide no solution where (I) the product varies in shape form one bag to another as where the product comprises a plurality of parts which are dropped at random into the bag; and (2) where the product assumes different positions from bag to bag as where it is dropped into the bag without regard to its orientation.

SUMMARY OF THE INVENTION The present invention overcomes the foregoing and other drawbacks of the prior art by providing a packaging system utilizing a highly resilient pressure pad for deflating loaded flexible wall containers.

The pressure plate includes a pluraltiy of individual elongated resilient elements each of which is collapsible independently of the other elements. The elements preferably have a test-tube shape including a thin cylindrical side wall closed at one end by a rounded end wall and open at the other end. An annular lip is formed integrally with the side wall around the open end.

A pair of base plates clamp the annular lips of the elements and securely position the elements so they extend side by side in a common direction away from the base plates. The rounded ends of the elements form a highly resilient pressure pad. The individually collapsible characteristic of the elements enables the pressure pad to conform to the shape of contents within a loaded container, and to expel air from the container without damagine the contents.

One of the base plates is apertured to receive the cylindrical side walls of the elements and to engage one side of the annular lips. The second base plate engages the opposite side of the lips. Threaded fasteners urge the two plates toward each other, securely clamping the annular lips therebetween. Apertures formed in the second base plate align with the open ends of the elements to permit the discharge of air from the elements as they collapse when brought into engagement with a loaded container. I

In the preferred embodiment, the pressure plate is mounted on one of a pair of relatively movable closure members in a packaging machine such as is described in the referenced Machine Patents. As the closure members are moved toward each other to close an open loaded container positioned therebetween, the resilient pressure pad elements gently engage the container. As the closure members continue to move toward each other, the resilient elements deform independently of each other to conform loaded container regions to the general shape of the container contents, and to collapse unloaded container regions thereby deflating the container.

Whereas, prior art pressure pads have typically been formed from one-piece structures, the individually independently acting resilient elements utilized in accordance with the present invention permit a much greater local differential deformation, wherein products of substantially any shape can be accommodated without the need for a pressure pad of specialized configuration.

It is a general object to provide a novel and improved packaging system utilizing resilient pressure pad for deflating loaded flexible wall containers without damaging their contents.

Other objects and a fuller understanding of the invention may be had by referring to the following description and claims taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional side elevational view of a portion of a packaging apparatus constructed in accordance with the present invention;

FIG. 2 is an exploded view on the same scale as FIG. 1 showing the details of construction of the container deflator assembly show in FIG. 1; and

FIG. 3 is an enlarged cross-sectional view of one of the resilient elements used in the deflator assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 a fragmentary portion of a packaging machine is shown generally at 10. With the exception of a pressure pad assembly shown generally at 100, the machine is constructed and functions as described in the referenced Machine Patents. A packaging web 12 of interconnected containers or bags is fed from a storage region, not shown, along a horizontal feed path to an idler roller 14. From the idler roller 14, the web 12 is directed forwardly and upwardly by a guide bar 15 toward a pair of feed rollers 16, 17. The web passes through the nip of the rolls 16, 17 and is fed downwardly along a substantially vertical path to a loading station, indicated generally by the numeral 50.

As a container 53 formed on the web 12 reaches the loading station 50, it is opened by a blast of air as described in the Machine Patents. The container 53 is then loaded with parts 52 discharged from a loading chute 51.

A pair of relatively movable closure members are provided to close the open loaded container. One of the closure members takes the form of a guard bracket 60. The other is a closure bar which is supported on rods 66 for movement toward and away from the guard bracket 60. As described in detail in the Machine Patents, the closure bar 64 carries a resilient pad assembly 67 for engaging the open end region of the container 53 and effecting its closure by moving it toward the guard bracket 60. e 1

A slot 61 is provided in the guard bracket 60. A gripper assembly 63 and a heater bar 62 are positioned inwardly of the slot 61. During the final inward movement of the closure bar 64, the closed upper end region of the container 53 is pressed through the slot 61 and into engagement with the gripper assembly 63 and the heater bar 62 to secure the closure by forming a heat seal.

In accordance with the present invention, the pressure pad assembly 100 is mounted on the closure bar 64 for movement with it. The pressure pad assembly 100 includes first and

second base plates

101, 102 which support a plurality of thin-walled resilient tubular elements 103. The elements 103 extend toward the container 53 and form a highlyresilient pressure pad which is effective, during inward movement of the closure bar 64, to gently expell excess air from the container 53 before the upper open end is closed.

Referring to FIGS. 2 and 3, the elements 103 are of test tube shape including a generally cylindrical relatively thin side wall 103a closed at one end by a rounded end wall 103b and open at the other end 1030. An enlarged annular lip 103d is formed around the end opening 1030. The walls 103a, l03b and the lip 103d are integrally formed from a resilient material such as silicone rubber.

In the preferred embodiment, the elements 103 are about2 inches in length and about three fourths inches in outside diameter. Elements of this size are available commercially from Davol, Inc., 69 Point Street, Providence, R1. 02901 under the designation Finger Cot No. 9798.

Referring to FIG. 2, the assembly includes a mounting bracket 105. Apertures 106 formed through the bracket receive threaded fasteners 107 to mount the bracket 105 on the closure bar 64. A pair of guide pins 108 are cantilevered by the bracket 105.

A clamping bracket 110 is provided with apertures 111 to receive the guide pins 108. End regions of the clamping bracket 110 are slotted at 112. Knurled thumb screws 113 extend through apertures 114 in the bracket 110 and provide a means of clamping the bracket 110 in place on the guide pins 108.

The first base plate 101 is secured to the clamping bracket 110 by threaded fasteners 118. The fasteners 1 18 extend through mounting apertures 119 in the base plate 101 and into threaded apertures 120 in the clamping bracket 120. A pair of guide pin apertures 121 are provided in the first base plate 101 to receive the guide pins 108. Auxiliary mounting and guide pin apertures 119a, 121a, are formed in one side region of the first base plate 101 to permit a 90 reorientation of the base plates relative to the clamping bracket 110 if desired.

An array of apertures 125 is formed in the first base plate 101. The elements 103 are positioned in the apertures 125 with the lips 103d in engagement with the base plate 101.

Threaded fasteners fasten the second base plate 102 to the first base plate 101. The fasteners 130 extend through apertures 131 in the second base plate 102 and are threaded into mounting apertures 132 in the first base plate 101. The fasteners 130 are tightened sufficiently to firmly clamp the lips 103d of the elements 103 between the

base plates

101, 102.

A plurality of holes 135 are formed in the second base plate 102 in alignment with the open ends 103C of the elements 103. The holes 135 freely permit the admission and discharge of air to and from the elements 103.

The resilient elements 103 are preferably arranged in a regular closely spaced side-by-side array. The 20 element array shown in FIGS. 1 and 2 can, of course, be expanded to include larger numbers of elements, or diminished to include a lesser number of elements as desired for a particular packaging operation. Guard bracket extensions 60a of various sizes are used as required to accommodate the various arrays of pressure elements 103.

In operation, as the closure bar 64 travels inwardly toward the guard bracket 60, the rounded ends 103b of the elements 103 engage the loaded container 53 and press it into engagement with the guard bracket 60 and guard bracket extension 60a. As the closure bar 64 continues its inward travel, the resilient elements 103 deform independently of each other, conforming loaded regions of the container 53 to the general shape of the container contents, and collapsing unloaded container regions to expell excess air. The elements also serve to maintain the container 53 in its deflated condition until the closure bar 64 fully closes the container and a heat seal is effected.

During the return stroke of the closure bar 64, the elements 103 return to their relaxed configuration and disengage the container 53.

As will be apparent, the resilient elements which form the pressure pad can be formed from a wide range of resilient materials supported on any of a variety of structures for use with many different types of collapsible containers. The independent individual action of the elements permits them to accommodate products of almost any shape and yet effectively expel excess air from their containers.

Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.

What is claimed is:

l. A packaging apparatus comprising:

a. positioning structure for supporting an open loaded container in a closure station;

b. a pair of closure members movable relatively toward each other to engage opposite sides of an open loaded container positioned in the closure station to close the container, and movable relatively away from each other to release the container; and,

c. container deflation means carried by one of said closure members and including resilient means positioned to engage the container prior to its being fully closed by said closure members;

d. said resilient means comprising a plurality of individual fluid filled collapsible elements, some of which are operative to conform loaded regions of the container to the general shape of the contents therein with others of said elements operative to collapse unloaded regions of the container as said members move relatively toward each other.

2. The apparatus of claim 1 wherein said deflation means further includes a base structure, said elements being supported by said base structure.

3. In a packaging apparatus:

a. feeding means for advancing a web of interconnected containers along a path of travel;

b. a loading station defined along said path of travel at which successive containers of said web are loaded;

c. structure defining a closure station along said path of travel at which successive loaded containers are closed, said closure station structure comprising first and second closure members disposed on opposite sides of said path of travel and closure member supporting structure supporting one of said first and second members for movement relative to the other member to close a loaded container therebetween; and,

d. container deflation means disposed adjacent said closure station for engaging a loaded container prior to closure thereof by said closure members to expel excess air from the loaded container, said deflation means comprising:

i. structure defining a support surface on one side of a path of travel and extending transversely of said path of travel;

ii. a plurality of resiliently deformable elements disposed on the side of said path of travel opposite to said support surface, said elements disposed in side-by-side relationship transversely of said path of travel with each element being individually resiliently deformable independently of adjacent elements; and,

iii. element supporting means effective to support said elements at a location in which each element is capable of resiliently engaging and collapsing an unloaded container portion against said support surface;

iv. said support surface, elements and element supporting means cooperating so that at least one of said elements resiliently engages a loaded portion. of a container to conform the container to the general shape of the contents and expels air from the container and elements which resiliently engage unloaded portions of the container collapse and expel air from such engaged container portions.

4. The apparatus of claim 3 wherein said elements are each resilient elongated elements extending toward the loaded container from said location.

5. The apparatus of claim 4 wherein:

a. said element supporting means includes a base structure; and,

b. said elements are supported by said base structure near one end region thereof and are positioned in aligned relationship withopposite end regions thereof projecting toward a loaded container positioned at said closure station.

6. The apparatusof claim 5 wherein:

a. said elements each comprise a thin wall tubular structure;

b. said one end region of each element being open to admit and discharge air;

c. said opposite end region of each element being closed;

d. said elements being supported by said base structure in such fashion as permits air to be admitted to and discharged from said elements through said one end region.

7. In a packaging apparatus of the type including structure for supporting an open loaded container at a closure station and a closure mechanism operative to close the container, the improvement of a container deflation means for deflating an open loaded container positioned at the closure station, comprising:

a. a pair of members movable relatively toward and away from each other to releasably engage a loaded container positioned therebetween at the closure station;

b. one of said members including a base structure and resilient means supported by said base structure;

c. said resilient means having a plurality of individual resilient portions projecting toward and engageable with a container positioned at the closure station and being operative upon relative movement of said members toward each other to expel air from the container by conforming loaded regions of the container to the general shape of the contents therein and collapsing unloaded regions of the container.

8. The apparatus of claim 7 wherein said resilient portions comprise separate elongated resilient elements supported near one end region by said base structure and extending in generally aligned relationship from said base structure toward a container positioned at said closure station.

9. In a packaging apparatus of the type including structure for supporting an open loaded container in a closure station and a closure mechanism operative to close the container, the improvement of a container deflation means for deflating an open loaded container positioned in the closure station, comprising:

a. a pair of members movable relatively toward and away from each other to releasably engage a loaded container positioned therebetween in the closure station; i

c. said resilient means having a plurality of individual resilient portions projecting toward and engageable with a loaded container positioned in the closure station andbeing operative upon relative movement of said members toward each other to conform loaded regions of the container to the general shape of the contents therein and to collapse unloaded regions of the container;

d. said resilient portions comprising separate elongated resilient elements supported near oneend region by said base structure and extending in generally aligned relationship from said base structure toward a container positioned in said closure station, said elements each comprising a thin walled tubular structure with said one end region being open to admit and discharge air and an opposite end region being closedby a thin curved end wall.

10. The apparatus of claim 9 wherein said elements each have an annular lip formed on said one end region and said base structure includes clamping means in engagement with said lips.

' plate is apertured to permit the admission and discharge of air to and from each of said elements through said open end regions.

13. A pressure pad for expelling excess air from loaded flexible wall containers comprising a supporting structure and a pluralityof thin walledresilient tubular elements supported by said structure and extending outwardly therefrom to define a plurality of resilient pad portions which are resiliently deformable substantially independently of each other when brought into engagement with a loaded flexible wall container to conform loaded container regions to the general shape of the contents therein and to collapse unloadedcontainer regions.

14. The pressure pad of claim 13 wherein said elements are supported in cantilever fashion from said structure and project outwardly from said structure in substantially parallel directions.

15. A packaging method comprising the steps'of:

a..positioning an open loaded container in aloadin station; I y b. loading the container;-

c. providing a pair of members at least one of which carries a plurality of resilient portions which-are deformable independently of each other;

d. expelling air from the container by disposing the container between the members and resiliently deforming said portions against thecontainer independently of each other to conform loaded portions of the container to the general shape of the contents therein and to collapse unloaded container'portions against the other member; and

e. securing the container closed.

16. The packaging method of claim 15 wherein the step of expelling air from the container includes supporting a'plurality of said resilient portions inside-byside relationship to extend in substantially parallel directions, and moving said portions into engagement with a loadedconta'iner to cause said resilient portions to deform independently .of eachother asrequired to expel excess air from the container.

17. A method of expelling excess air from a loaded flexible wall container comprising the steps of:

a. providing a pair of members which are-movabletoward and away from each other with at least one of the members carrying a plurality ofresilient portions projecting toward the other member, each of which portions is deformable independently of the otherportions;

b. positioning a loaded flexible wall container between said members; v

c. moving said members relatively toward each other to compress the container between said portions and the other said member;

d. conforming at least one loaded portion of the container to the contents while displacing air from said one loaded portion by engaging and resiliently deforming at least one of said resilient portions against said container portion while relatively moving said members; and,

e. collapsing an unloaded container portion to displace air therefrom by engaging and resiliently deforming at least another of said resilient portions against said unloaded container portion while moving said members.

Claims

1. A packaging apparatus comprising: a. positioning structure for supporting an open loaded container in a closure station; b. a pair of closure members movable relatively toward each other to engage opposite sides of an open loaded container positioned in the closure station to close the container, and movable relatively away from each other to release the container; and, c. container deflation means carried by one of said closure members and including resilient means positioned to engage the container prior to its being fully closed by said closure members; d. said resilient means comprising a plurality of individual fluid filled collapsible elements, some of which are operative to conform loaded regions of the container to the general shape of the contents therein with others of said elements operative to collapse unloaded regions of the container as said members move relatively toward each other.

3. In a packaging apparatus: a. feeding means for advancing a web of interconnected containers along a path of travel; b. a loading station defined along said path of travel at which successive containers of said web are loaded; c. structure defining a closure station along said path of travel at which successive loaded containers are closed, said closure station structure comprising first and second closure members disposed on opposite sides of said path of travel and closure member supporting structure supporting one of said first and second members for movement relative to the other member to close a loaded container therebetween; and, d. container deflation means disposed adjacent said closure station for engaging a loaded container prior to closure thereof by said closure members to expel excess air from the loaded container, said deflation means comprising: i. structure defining a support surface on one side of a path of travel and extending transversely of said path of travel; ii. a plurality of resiliently deformable elements disposed on the side of said path of travel opposite to said support surface, said elements disposed in side-by-side relationship transversely of said path of travel with each element being individually resiliently deformable independently of adjacent elements; and, iii. element supporting means effective to support said elements at a location in which each element is capable of resiliently engaging and collapsing an unloaded container portion against said support surface; iv. said support surface, elements and element supporting means cooperating so that at least one of said elements resiliently engages a loaded portion of a container to conform the container to the general shape of the contents and expels air from the container and elements which resiliently engage unloaded portions of the container collapse and expel air from such engaged container portions.

5. The apparatus of claim 4 wherein: a. said element supporting means includes a base structure; and, b. said elements are supported by said base structure near one end region thereof and are positioned in aligned relationship with opposite end regions thereof projecting toward a loaded container positioned at said closure station.

6. The apparatus of claim 5 wherein: a. said elements each comprise a thin wall tubular structure; b. said one end region of each element being open to admit and discharge air; c. said opposite end region of each element being closed; d. said elements being supported by said base structure in such fashion as permits air to be admitted to and discharged from said elements through said one end region.

7. In a packaging apparatus of the type including structure for supporting an open loaded container at a closure station and a closure mechanism operative to close the container, the improvement of a container deflation means for deflating an open loaded container positioned at the closure station, comprising: a. a pair of members movable relatively toward and away from each other to releasably engage a loaded container positioned therebetween at the closure station; b. one of said members including a base structure and resilient means supported by said base structure; c. said resilient means having a plurality of individual resilient portions projecting toward and engageable with a container positioned at the closure station and being operative upon relative movement of said members toward each other to expel air from the container by conforming loaded regions of the container to the general shape of the contents therein and collapsing unloaded regions of the container.

9. In a packaging apparatus of the type including structure for supporting an open loaded container in a closure station and a closure mechanism operative to close the container, the improvement of a container deflation means for deflating an open loaded container positioned in the closure station, comprising: a. a pair of members movable relatively toward and away from each other to releasably engage a loaded container positioned therebetween in the closure station; b. one of said members including a base structure and resilient means supported by said base structure; c. said resilient means having a plurality of individual resilient portions projecting toward and engageable with a loaded container positioned in the closure station and being operative upon relative movement of said members toward each other to conform loaded regions of the container to the general shape of the contents therein and to collapse unloaded regions of the container; d. said resilient portions comprising separate elongated resilient elements supported near one end region by said base structure and extending in generally aligned relationship from said base structure toward a container positioned in said closure station, said elements each comprising a thin walled tubular structure with said one end region being open to admit and discharge air and an opposite end region being closed by a thin curved end wall.

11. The apparatus of claim 10 wherein said clamping means includes: a. a pair of plates; b. one of said plates being apertuted to receive said thin wall tubular structure and to engage one side of said lips; c. the other of said plates being positioned in engagement with the opposite side of said lips; and d. fastening means urging said plates together with said lips clamped therebetween.

12. The apparatus of claim 11 wherein said other plate is apertured to permit the admission and discharge of air to and from each of said elements through said open end regions.

13. A pressure pad for expelling excess air from loaded flexible wall containers comprising a supporting structure and a plurality of thin walled resilient tubular elements supported by said structure and extending outwardly therefrom to define a plurality of resilient pad portions which are resiliently deformable substantially independently of each other when brought into engagement with a loaded flexible wall container to conform loaded container regions to the general shape of the contents therein and to collapse unloaded container regions.

15. A packaging method comprising the steps of: a. positioning an open loaded container in a loading station; b. loading the container; c. providing a pair of members at least one of which carries a plurality of resilient portions which are deformable independently of each other; d. expelling air from the container by disposing the container between the members and resiliently deforming said portions against the container independently of each other to conform loaded portions of the container to the general shape of the contents therein and to collapse unloaded container portions against the other member; and e. securing the container closed.

16. The packaging method of claim 15 wherEin the step of expelling air from the container includes supporting a plurality of said resilient portions in side-by-side relationship to extend in substantially parallel directions, and moving said portions into engagement with a loaded container to cause said resilient portions to deform independently of each other as required to expel excess air from the container.

17. A method of expelling excess air from a loaded flexible wall container comprising the steps of: a. providing a pair of members which are movable toward and away from each other with at least one of the members carrying a plurality of resilient portions projecting toward the other member, each of which portions is deformable independently of the other portions; b. positioning a loaded flexible wall container between said members; c. moving said members relatively toward each other to compress the container between said portions and the other said member; d. conforming at least one loaded portion of the container to the contents while displacing air from said one loaded portion by engaging and resiliently deforming at least one of said resilient portions against said container portion while relatively moving said members; and, e. collapsing an unloaded container portion to displace air therefrom by engaging and resiliently deforming at least another of said resilient portions against said unloaded container portion while moving said members.