US3468451A

US3468451A - Container with disposable liner

Info

Publication number: US3468451A
Application number: US717525A
Authority: US
Inventors: Clarence B Coleman
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-04-01
Filing date: 1968-04-01
Publication date: 1969-09-23
Anticipated expiration: 1986-09-23
Also published as: BE726905A; DE1806148A1; NL6815868A; ES359109A1; GB1267596A; DE6804717U; FR1600078A

Description

P 3, 1969 c. COLEMAN CONTAINER WITH DISPOSABLE LINER Filed April 1, 1968 FIG. 1

INVENTOR. CLARENCE B. COLEMAN BY Z0 m away/aim 6 3 .a 8 7 A 5 w (x 4 8 M 3 m 0 m 4 FIG. 4

ATTORNEYS United States Patent US. Cl. 220-63 Claims ABSTRACT OF THE DISCLOSURE A container with axially spaced end walls and a flexible tubular liner disposed therein for storing and transporting fluid material. At least one end of the liner is gathered and projects through one of the openings. The liner is sealed relative to the container to prevent seepage of the fluid material into the space between the liner and the walls of the container. The projecting end of the liner extends radially outward from the opening through which it projects to the exterior of the container. Means including a resilient sealant material and a closure for closing the one opening are biased toward the adjacent end wall and the radially extending portion of the liner to establish a seal between the sealant material and the liner and prevent fluid from escaping from the container or entering the space between the liner and walls of the container.

BACKGROUND OF THE INVENTION Field of the invention this invention relates to such a container wherein the access openings have transverse dimensions substantially smaller than those of the container and wherein the liner, which may be of a relatively uniform tubular construction, can be conveniently sealed adjacent at least one of the openings that projects to the exterior of the container.

State of the prior art The use of a flexible envelope or liner disposed within a rigid shell to receive and hold a material therein is known in the art. Such composite containers are useful when it is desired to isolate the confined material from the ambient atmosphere as well as from the shell itself. The use of such liners may also obviate the need to clean the inside of the container, while the liner or flexible envelope can be disposed of after its use.

Prior art envelopes or liners with which I am familiar generally have a configuration complementary to that of the surrounding shell or container. Since the containers generally have axially spaced, opposing end walls, including an opening having a transverse dimension substantially smaller than the transverse dimension of the container, the shape of the liner is intricate. To manufacture such liners preformed to shape is relatively diflicult and expensive.

Some prior art liners are of sack-like construction and include a neck section adjacent the open end thereof. The throat opening through the neck is usually of considerably smaller cross section than the main body of the liner. Since the liner may then be scaled to the container by engagement of the neck section at the container opening, such reduced neck dimension facilitates sealing, particularly where the closure for the entire container bears against a portion of the neck section.

Accordingly, such a liner may, in accordance with prior art techniques, require preforming and be constructed to relatively close tolerances so that the formation of wrin- Patented Sept. 23, 1969 kles when it is sealed to the container is avoided, since such wrinkles can cause undesirable leaks. This in turn requires the stocking of often several liners for containers of like capacity it such containers have access opening in their end walls of different sizes. The cost of lining the container is thereby further increased.

SUMMARY OF THE INVENTION The present invention provides a container having a pair of axially spaced opposing end Walls with openings therein which have maximum transverse dimensions subtainer. As used herein, the term end walls is intended to include cone-shaped end sections as well as relatively fiat or dish-shaped end walls. Briefly, the container includes a flexible, tubular liner disposed therein whose circumference is at least as great as the internal circumference of the main portion of the container with at least one of its ends projecting past one of the openings. The other end of the liner is sealed to the container at the other opening to prevent seepage of materials stored therein into a space between the liner and the container wall. Means are further provided adjacent at least one of the openings to seal the interior of the liner and the container from the exterior and leakage from within the container whereby material may seep between the liner and the container wall.

More particularly, projecting end of the liner is arranged to extend radially away from at least one of the openings, the one requiring more critical sealing. A closure assembly is provided including a closure plate and a resilient sealant material such as a gasket, disposed between the closure plate and the radially extending portion or skirt of the liner. When the closure plate is biased toward the adjacent end wall, the plate impresses the liner skirt against the gasket so as to seal the interior of the container and the main portion of the liner within the container from the exterior.

In the presently preferred form of this invention, the radially extending portion or liner skirt is folded over so that the end of the liner is disposed adjacent the center portion of the closure. An annular ring constructed of the material having a hardness greater than that of the resilient sealant material is disposed between the folded over portion of the liner and the oppositely disposed sealant material or gasket. Such ring provides for increased pressure over a small annular hand between the gasket and the adjacent liner, so that a positive seal is obtained even though the liner material includes wrinkles which heretofore have caused leaks. The annular gasket preferably is made of a relatively soft, rubber-like material; and, in the preferred form of this invention, one such gasket is disposed on each side of the annular ring between the folded over portions of the liner. Since most such containers are in an upright condition, that is the axis of the container is substantially vertical in use, the opening adjacent which the liner is folded over is at the lower end wall of the container. The high quality of the seal thus obtained permits the withstanding of the hydrostatic head to which the lower closure assembly is subjected when the container is filled with a liquid, without leaks or seepage.

Cylindrically tubular liners are readily available, relatively inexpensive, and permit substantial cost reductions in providing a liquid carrying container with a disposable liner. The shape and more particularly the diameter of the tubular liner is not critical as long as it is suflicient to contact the rigid container walls when filled with liquid so that possible ruptures of the liner from the weight and the pressure exerted by the fluid are prevented. A particular feature of the present invention is that while the liner may have a greater diameter than the maximum inside transverse dimension of the container, the dimension of the access opening becomes relatively unimportant as far as the configuration of the liner is concerned, since a positive seal is established even though the liner is wrinkled at the sealing point.

Moreover, in accordance with the present invention, the liner is easily and quickly installed in the container which makes it more feasible to dispose of the liner after each use. In the prior art, the expense of disposing of the rela tively expensive liners frequently demanded that it be reused as often as possible. If the stored fluid contans abrasives, damage to the liner could result and in turn eventual loss of protection of the container walls, which may in all likelihood cause loss and contamination of the stored materials.

Although the upper ends of the liner and container can be sealed in the same manner at the lower ends, in many applications where the fluid stored in the container need not be protected from the atmosphere and in instances where the container is in an upright position during operation, less effective, conventional seals can be provided there. Thus, the upper end of the container may, for example, be gathered and clamped to a cylindrical protrusion projecting into the container from a barrel cover of the container. Other conventional sealing methods can, of course, be employed. In the absence of hydrostatic pressure differentials, such seals are sufiicient to prevent fluid stored in the container from escaping into the space between the liner and the container walls or to the exterior of the container.

In the specification which follows, the example shown is that of a substantially cylindrical container; but it is understood that my invention may be embodied in containers having other transverse cross sections as well, e.g. elliptical, polygonal such as rectangular, etc.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is an elevational view, partially in section, of an upright, cylindrical container provided with a tubular liner and a sealed lower access opening constructed in accordance with the present invention;

FIGURE 2 is a fragmentary enlarged cross sectional view of the lower access opening and shows the sealing arrangement between the container, the lower closure and the liner in greater detail;

FIGURE 3 is a fragmentary sectional view similar to FIGURE 2 of another embodiment of the invention; and

FIGURE 4 is a fragmentary, sectional view similar to FIGURE 2 of another embdiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGURE 1, a generally cylindrical container is defined by a preferably circularly cylindrical side wall 12 and a pair of axially spaced confronting upper and

lower end walls

14 and 16, respectively. A platform 18 supports the container in an upright position. Each end wall includes a preferably circular opening 20 to provide access to the interior of the container. An elongate tubular liner 22 is disposed within the container and has a length greater than the axial length of the container. Typically, such liner may be constructed of a relatively thin, flexible material, such as polyethylene, Mylar, or polyvinylchloride (PVC). The liner is circularly cylindrical and has a diameter which is at least as great as the inside diameter of side walls 12.

The upper end wall 16 includes an upwardly projecting neck 24 which has a bulb-shaped cross section. The upper end of the liner projects through the opening in the upper end wall and is stretched over the bulb-shaped neck. A circular barrel cover 26, having a flared and arcuately shaped periphery with a curvature complementary to that of the bulb-shaped neck, is placed over the end of the liner disposed on the neck. More particularly, a conventional marmon clamp secures the liner to the neck, thereby establishing a seal between the interior and exterior of the liner; and the barrel cover is secured to the opening to complete the closure. The portion of the liner stretched over the bulb-shaped neck includes wrinkles since its end has been gathered to a diameter substantially less than that of the remainder of the liner, the latter having a diameter at least equalling that of the side wall 12; nonetheless, a sufficient seal is established to prevent the accidental escape of fluid stored in the container since the seal is not subjected to a hydrostatic head. The barrel cover may also include suitable plumbing (not shown) to permit the introduction of fluid material into the interior of'the container without having to remove the cover.

Alternative constructions for sealing the upper end of the liner and container may, of course, be employed. For example, the barrel cover may be provided with an inwardly extending annular projection (not shown) to which the upper end of the liner is secured with a suitable clamp. In such case, the annular projection is of suflicient length to permit the application of a clamp and, preferably, at its inward or lowermost end it includes a radially outwardly extending bead along the periphery of the protrusion to prevent the upper end of the liner and the clamp from slipping off the projection.

Referring to FIGURES 1 and 2, lower end wall 16 includes an outwardly projecting flange 30 which defines opening 20 in the lower end wall and through which a length of liner 22 projects and closure assembly 21 is provided at the lower opening. An annular gasket 32 constructed of a resilient material such as. a rubber compound, for example, has a substantially rectangular cross section and is disposed adjacent a face 34 of the end flange. Such gasket may be bonded to the end flange to maintain it in position at all times.

A closure or cover plate 36 has a like periphery as the periphery of the end flange so that it can be lined up therewith and is provided with a gasket 38 which may be identical to gasket 32. Gasket 38 also may be bonded to the closure plate to maintain position and obviate the necessity of having to align it each time the closure plate is closed. The closure plate is preferably hingedly attached to end wall 16 so that it can be pivoted between a closed position, in which it is substantially parallel to face 34 of end flange 30, and an open position, in which it depends from the end flange. In the open position free access to the interior of the container through opening 20 in the lower end wall is provided. A plurality of eye bolts 40 are hingedly secured to a cylindrical portion 42 of the end flange and to the end flange by means of gussets 43. When the closure is in its closed position the eye bolts are disposed in notches 44 of the closure which extend radially inward from the periphery thereof. Wing nuts 46 are tightened against the closure plate to provide bias toward the lower end wall and

gaskets

32 and 38 toward each other. By loosening the wing nuts and pivoting the eye bolts out of the notches the closure is free to pivot into its open position.

A drainage tube 48 is centrally attached to the closure and includes suitable means 50 for capping shut its free end. The drainage tube permits drainage of the contents of the container without opening closure plate 36. The free end of the drainage tube may, therefore, be provided with suitable pipe threads to attach pipes or hoses to facilitate drainage of the liquid from the container and to connect pumping equipment (not shown) thereto if the contents of the container must be pressurized to deliver them to the desired location.

To seal the lower end or skirt of liner 22 projecting through opening 20 in the lower end wall, the skirt is gathered and arranged to project past seal gasket 32 and radially outwardly beyond the opening. An annular ring 52 is constructed of a material having a greater hardness than that of the seal gaskets, preferably of steel or stainless steel to prevent corrosion when it contacts fluid stored in the container. The ring is placed in operative position, as seen for example in FIGURE 2 so that the radially outward extending length of the liner may be folded back over the ring by about 180, thereby causing end 54 of the liner to be disposed adjacent the center of closure plate 36 when the plate is thereafter placed in its closed position. When wing nuts 46 are tightened, the closure plate biases the seal gaskets toward annular ring 52 and thereby causes a relatively narrow band of high pressure to occur at the contacting portions of annular ring 52, the adjacent folded portions of the liner, and the seal gaskets. This high pressure area effectively seals the interior of the liner and the container from the exterior and prevents seepage or leaks of fluid past the space between the seal gaskets and the annular ring even if the closure assembly is subjected to a hydrostatic head from the fluid stored in the container, and even though the liner in the vicinity of the annular ring and the seal gaskets is wrinkled because it has been gathered to substantially reduce its diameter to that of annular ring 52. Such closure assemblies, where the liner is wrinkled, could heretofore not be sealed satisfactorily, particularly when subjected to a hydrostatic head. To facilitate the sealing and to nest the annular ring and the folded portion of the liner in the seal gaskets, the latter preferably are fabricated of firm yet yieldable material which, when pressed against by ring 52 as shown, form annular grooves 56 with an arcuate cross sectional profile. This concentrates the pressure area between the seal gaskets, the liner, and the annular ring over a portion of the cross sectional periphery of the annular ring and enhances the sealing action.

The construction of the sealing arrangement described in the preceding paragraphs not only prevents seepage or leakage of fluid stored in the container to the exterior, but also completely seals and prevents migration of the fluid past the seal to the space intermediate the liner and side walls 12. Particularly if the fluid is a corrosive one, such seepage can seriously damage the container and, in due time, make it unusable.

It has been discovered that within limits a decrease in the cross sectional diameter of annular ring 52 increases the sealing effectiveness of the closure assembly and its ability to withstand increased hydrostatic heads. Best results have been obtained with a ring having a cross sectional diameter of about subjected to a hydrostatic head of several pounds per square inch and a low viscosity fluid such as water. Larger diameter cross section annular rings have a tendency to cause seepage of the fluid past the sealing surfaces at lesser hydrostatic heads, making it appear that the sealing qualities of the joint are a direct function of the unit pressure between the

annular gaskets

32 and 38 and the liner material. At the same time, however, annular rings having larger cross sectional diameter are stronger and less susceptible to damage when subjected to rough handling, which might cause them to be deformed out of round and ultimately become unusable.

The arrangement shown in FIGURE 2 is the presently preferred one; however, if the hydrostatic head acting on the closure assembly is not excessive, the joint can be simplified within the scope of this invention as shown in FIGURE 4. There the seal may be established without the use of pressure of annular ring 52 as shown in FIG- URES 2 and 3 by arranging the length of liner projecting past opening in the lower end wall so that liner skirt 22 extends radially outward from the opening without a re-entrant fold. Seal gasket 38 is provided to bias the liner against face 34 of the end flange. The end flange may, however, be provided with an annular protrusion such as shown by ridge 57 projecting toward closure plate 36. Empressment of ridge 57 upon the skirt increases the sealing pressure over the relatively narrow annular band defined thereby thus enhancing the fluid-tightness of the seal assembly further. Of course, even with such a relatively simplified embodiment of the invention, the radially outward extending portion of the liner could be folded back so as to terminate the liner skirt within the region of the closure plate; and the liner skir'teither in single layer or in folded back conditioncould, as described hereinabove, be sealably clamped between one or two annular seal rings. However, maximum installation efiiciency and sealing effectiveness of the liner skirt and closure plate assembly when subjected to a hydrostatic head is obtained when an annular ring, such as ring 52 shown in FIGURES 2 and 3, is disposed between the seal gaskets and the liner skirt folded around such ring.

Referring again to FIGURE 3, another alternative embodiment of the invention is shown wherein one of the seal gaskets, for example seal gasket 32 adjacent closure 36, is provided with projections to add secondary annularly shaped sealing bands. More particularly, with reference for a moment to the embodiment of FIGURE 2, seal gasket 38 shown therein is replaced, as disclosed in FIG- URE 3, by seal gasket 58. Moreover, gasket 58 is shaped to define a pair of upwardly extending

annular projections

60 and 62, the latter being radially spaced apart so as to establish therebetween recess 59 for receiving annular ring 52 when operably installed. Projection 60 is of a suflicient height to engage seal gasket 32 when the closure plate is secured in its closed position; and, similarly, projection 62 is of a suflicient height to bias the folded over portions of the liner adjacent the annular ring toward the upper annular seal gasket 32, thereby establishing secondary sealing surfaces to provide the closure assembly an effective seal under yet higher hydrostatic pressures.

Turning now to the operation of the container. barrel cover 26 is removed from the container; and closure plate 36 is opened to permit insertion of liner 22. The tubular liner is gathered and inserted into the container, preferably from above; and the lower end or skirt portion of the liner is pulled past opening 20 in lower end wall 16. The upper end of the liner is then placed over the bulbshaped neck 24; barrel cover 26 is next placed thereon; and the upper end is closed and sealed by applying marmon clamp 28 thereto. Thereafter, annular ring 52 is inserted up into the liner skirt interior until the ring is adjacent seal gasket 32 on the lower end flange. This automatically extends the projecting lower end of the liner radially outward from opening 20 in the lower end wall. The remaining portion of the liner is now folded inward and under the annular ring so that end 54 is positioned within the opening in the lower end wall adjacent the center of closure plate 36, when the latter is closed. The liner skirt end is pulled tightly against the annular ring; the closure plate is hingedly rotated into its closed position and tightened with wing nuts 46 so as to bias the seal gaskets toward each other and annular ring 52. At the same time, the gaskets are pressed against face 34 of the end flange and the closure plate so that a complete seal between the interior of the container, and more particularly of the liner and the exterior, as well as between the interior of the liner and the space between the liner and side walls 12 is obtained. Before closure is completed, internally the liner is spread out so that it is generally in its final position in contact with the ends and wall of the container. Fluid material may now be introduced into the container through appropriate piping and plumbing (not shown) in the barrel cover or, if preferred, from below through drainage tube 48. The filling of the container with the fluid acts to press the liner into contact with the walls and is supported by the walls of the container. Since the tubular liner has a diameter at least as large as that of the inside of the container, it is not subjected to stresses from the weight or pressure of the material and thus avoids rupturing. If the liner has a greater diameter than the container, folds may form on the interior which are, however, of no effect since such folds are firmly supported by the walls.

Spring clamps 64 may be provided as best seen in FIG- URE 2 to support annular ring 52 during installation, thereby to facilitate use of the ring and eliminate the necessity of somehow manually holding the ring in place until closure plate 36 is secured. In the embodiment shown, each such spring clamp comprises shank 66 having formed at one end thereof toe 67 and at the other end clamping ferrule 68. Each spring clamp is secured to annular ring 52 at spaced intervals thereabout by suitable attachment of the free end of toe 67 to the ring. As the annular ring is inserted into operative position, the shank and ferrule portions of the spring clamp attached thereto are forced through the restricted opening defined by cylindrical Wall 42. Thus, the clamp ferrule and shank are urged inwardly to assume the restrained position shown by the phantom-line partial view at 65. Shank 66 is shaped to such length that when ring 52 comes to rest adjacent gasket 32, clamping ferrule 68 emerges from the restriction of wall 42 to engage inner surface 68 of lower end wall 16; and, when so located, the ferrule and shank are free to expand radially outwardly to an unrestrained or gripping position as shown in the drawing, thereby to hold annular ring 52 in operative position during installation and permit securement of closure plate 36.

Since the container liner embraced by this invention permits the construction of the container of relatively inexpensive, non-corrosion resistant material, such as ordinary carbon steel; only closure plate 36, ring 52, and clips 64 are exposed to contact with the fluid in the container, so only the latter parts need be constructed of a corrosion resistant material such as stainless steel, for example.

The fluid in the container may be expelled through drainage pipe 48 as described hereinabove. Afterward, the liner may be disposed of by removing the barrel cover at the top of the container and opening the closure at the bottom. Thereafter, it is pulled through the container; and, at the same time, the container is ready for insertion of a new liner by following the above outlined steps.

I claim:

1. In a container having opposing end walls and an access opening in at least one of the end walls, the opening having a maximum transverse dimension substantially less than the transverse dimension of the container, the improvement comprising:

a tubular liner constructed of a flexible material and having a length greater than an axial length of the container, one end of the liner projecting past said opening in the one end wall and another end being sealed relative to the other end Wall and means including a closure cooperating with said one end wall for sealing the lining relative to said one end wall,

and wherein said liner circumference is at least as great as the maximum transverse internal circumference of said container.

2. Apparatus according to claim 1, including a folded portion in the projecting length of the liner, and disposed radially outward of the axial projection of the opening in said one end wall intermediate said one end wall and the closure.

3. Apparatus according to claim 2, including means adjacent the fold for spacing portions of the projecting length of liner defining said folded portion apart from each other and a gasket adjacent the folded portion exteriorly of the liner.

4. Apparatus according to claim 3, wherein the spacing means includes an annular ring constructed of a material having a hardness greater than that of the gasket.

5. Apparatus according to claim 4, wherein the gasket includes an annular gasket ring disposed on each side of the annular ring intermediate said folded portion of the lines and the closure and said one end wall.

6. Apparatus according to claim 5, wherein the seal gasket adjacent the closure includes annular projections facing toward the container and having a configuration to apply pressure against the other seal gasket when the closure is biased toward the container.

7. Apparatus according to claim 3, including means adjacent and radially inward of said folded portion for increasing pressure between the gasket and the liner adjacent the folded portion over a narrow annular area.

8. Apparatus according to claim 7, wherein said means for increasing pressure includes an annular ring and means for securing the annular ring to the container and for positioning said annular ring relative to said opening.

9. Apparatus according to claim 1, wherein the projecting portion of the liner is extended radially outwardly and folded so that the end of the liner is disposed adjacent a center portion of the closure.

10. Apparatus according to claim 8, wherein a gasket is disposed intermediate the radially outwardly extending portion of the liner, the adjacent end Wall and the closure, respectively, the gaskets being positioned opposite said annular ring.

References Cited UNITED STATES PATENTS 2,503,339 4/1950 Iandus 220-63 3,377,766 4/ 1968 Nelson 22063 GEORGE T. HALL, Primary Examiner