US3268145A

US3268145A - Container closing means

Info

Publication number: US3268145A
Application number: US416669A
Authority: US
Inventors: Gerald C Bauer
Original assignee: Mead Corp
Current assignee: Mead Corp
Priority date: 1963-02-25
Filing date: 1964-11-09
Publication date: 1966-08-23
Anticipated expiration: 1983-08-23

Description

Aug. 23, 1966 G. c. BAUER CONTAINER CLOSING MEANS Original Filed Feb. 25, 1963 5 Sheets-Sheet 1 INVENTOR. 60mm C. Efil/ER Y 1/, %M@/%W ATTORNEY! G. C. BAUER CONTAINER CLOSING MEANS Aug. 23, 1966 5 Sheets-Sheet 5 Original Filed Feb. 25, 1963 I BYGERHLD 22 b? /g- 7 %%7WV% M H TIORNEYS' Aug. 23, 1966 G. c. BAUER CONTAINER CLOSING MEANS Original Filed Feb. 25, 1963 5 Sheets-Sheet 4 m M vw G. C. BAUER CONTAINER CLOSING MEANS Aug. 23, 1966 Original Filed Feb. 25, 1963 5 Sheets-Sheet 5 INVENTOR.

A TTORIYEYJ' United States Patent 3,268,145 CONTAINER CLOSING MEANS Gerald C. Bauer, Portage Township, Kalamazoo County, Mich., assignor, by mesne assignments, to The Mead Corporation, Dayton, Ohio, a corporation of Ohio Original application Feb. 25, 1963, Ser. No. 261,941, now Patent No. 3,195,426, dated July 25, 1965. Divided and this application Nov. 9, 1964, Ser. No. 416,669 3 Claims. (Cl. 2295.6)

This application is a division of my copending application Serial No. 261,941, filed February 25, 1963, now Patent No. 3,195,426.

This invention relates to container structures and methods of making same and it relates more particularly to the interlocking of one end of a fibrous, as paper, cylindrical container with a metallic container end.

The broad concept of making the sides of a container from a fibrous material, such as paper, and the end of the container from metal is very old and a multitude of method-s have been suggested for assembling such sides and ends together. Some of these have involved spinning procedures and others have involved the use of dies which move in a direction parallel with the axis of the container. However, the procedures thus far developed have not, insofar as I am aware, provided a simple mechanism capable of use under field conditions and capable of use where the container sides are made of relatively light gauge material.

In the present instance, the invention has been devel oped for the specific purpose of providing containers for the handling and transporting of frozen foods, grease compositions and, in appropriate cases, asphalt. Such containers are of relatively large size and must have a high degree of strength. Further, the conditions under which material is prepared and introduced into the con-' tainers are such that the containers are preferably delivered to the point of assembly and filling in a flat condition. The containers are erected, assembled and filled at such point, necessarily under field conditions. Thus, the mechanism by which such assembly is carried out must be relatively simple, capable of easy transportation and operable without precise control of the mechanical operations involved. This rules out many assembly methods, such as spinning methods, which are well adapted only for use under closely controlled conditions, such as in a factory.

A further problem with certain structures of the prior art is that the metallic parts used for the ends of the containers have upstanding rims of one sort or another. These rims are often flared outwardly slightly either to enable them to nest better with each other or to enable a rolling or spinning operation to be started more easily than would be the case if they extended substantially perpendicularly to the plane of the end wall of the container. However, while this type of structure is convenient as far as minimizing the space required for transporting such ends is concerned, the ends often adhere together with such force that it is extremely difficult to separate them for use, particularly where such separation is done by hand under field assembly conditions. In some cases it has been impossible to separate the ends from each other without inflicting such damage to one or more of them as to render them unfit for use. Such separation, at the least, is inconvenient and time consuming and, in many cases, result-s in a substantial loss due to damaged parts.

Further, after the containers are filled they often are moved by rolling same on their lower edges. Accordingly, it is desirable that the assembly method, and resulting product, be such that a metallic rim is provided along the lower edge of the container so that such rolling can be carried out with a minimum of effort on the ice part of the workman and at the same time with a minimum likelihood of damage to the container. It is further desirable that such assembly method, and resulting product, although designed primarily for the assembly of the side of the container to the bottom thereof, also be readily adaptable by only simple modifications to the application of a metallic top to the container.

While the packaging of frozen foods, etc. under field conditions has been set forth above as illustrating the specific need out of which the present invention arose, it will be recognized that such specific example is for illustrative purposes only and that the container structure and assembly procedure of the present invention can be used advantageously for a wide variety of purposes.

Accordingly, the major objects of the invention include the following:

(1)To provide a container, in which a cylinder of fibrous material which constitutes the sides of the container is assembled with a metallic end.

(2) To provide a container, as aforesaid, in which the said sides and end of the container are rolled together into an intimate and leak-proof relationship with each other.

(3) To provide a container, as aforesaid, whereby the container can be. assembled from parts which are shipped in flat condition.

(4) To provide a container, as aforesaid, in which the blank from which the end of the container is formed can be made without a flared rim so that it will not nest appreciably when stacked with similar ends and will accordingly, not adhere to other ends when it is being separated for use.

(5) To provide a container, as aforesaid, which can be effectively preformed under field conditions by readily portable equipment.

(6) To provide a container, as aforesaid, which provides a metal rim along an end edge of the container whereby the container may be rolled on same with a minimum likelihood that damage to the container will result therefrom.

(7) To provide a container, as aforesaid, which can by only slight modifications also be made applicable to applying covers to the container.

Other objects and purposes of the invention will be apparent to persons acquainted with devices of this general sort upon reading the following specification and inspecting the accompanying drawings.

In the drawings:

FIGURE 1 is an elevational view, partially broken away, of the bottom portion of a container construction in accordance with the invention, said container being shown in an inverted position.

FIGURE 2 is an enlarged, fragmentary, sectional view of the parts which are to be assembled to form a container, together with the important working parts of the assembly apparatus, the same being in a position immediately prior to the actual assembly procedure.

FIGURE 2a is a fragmentary, sectional view through the edge portion of the closure member as manufactured and before being assembled to the container side wall.

FIGURE 3 is a view similar to FIGURE 2 showing the parts immediately after the commencement of the assembly procedure.

FIGURE 4 is a view similar to FIGURE 2 showing the parts at a later time in the assembly procedure.

FIGURE 5 is a view similar to FIGURE 2 showing the parts substantially at the end of the assembly procedure.

FIGURE 6 is a view similar to a fragment of FIG- URE 5 and showing a further step of the assembly procedure.

FIGURE 7 is a fragmentary, sectional view of an 3 assembled container showing one kind of top which can be used therewith.

FIGURE 8 is a view similar to FIGURE 7 showing another kind of top.

FIGURE 9 is a view similar to FIGURE 7 showing yet another kind of top.

FIGURE is a view similar to FIGURE 3 showing a modified mandrel and plunger structure.

FIGURE 11 is an enlarged, fragmentary sectional view similar to FIGURE 2 but illustrating an alternate container construction and alternate working parts of the assembly apparatus.

FIGURE 12 is a view similar to FIGURE 11 showing the parts immediately after the commencement of the assembly procedure.

FIGURE 13 is a view similar to FIGURE 11 showing the parts at a later time in the assembly procedure.

FIGURE 14 is a view similar to FIGURE 11 showing the parts substantially at the end of the assembly procedure.

FIGURE is an enlarged, fragmentary sectional view, generally similar to FIGURE 10, of an alternate rim construction for the top of a container together with some of the important parts of an alternate assembly apparatus construction, the same being in a position immediately prior to the actual assembly procedure.

FIGURE 16 is a view similar to FIGURE 15 showing the parts substantially at the end of the assembly procedure.

In carrying out the objects and purposes above set forth, I have provided a container comprised of a cylinder 1 of fibrous material, such as paper, and a metallic closure member 2 which closes one end of said cylinder and which is connected to said cylinder by an interlock structure 3. The container is shown in an inverted position which is the normal position for assembly.

The cylinder 1 may be made of any convenient fibrous material, of any desired type or thickness, so long as the end portion thereof is capable of being tightly curled upon itself as described in detail hereinbelow. For example, in one typical embodiment of the invention the cylinder 1 is made of kraft paper approximately .031 inch thick.

The closure member 2 is made of any convenient metal, such as aluminum or steel, and the initial shape of the closure member is shown in FIGURES 2 and 2a. The closure member 2 is comprised of a base wall 17 and an upstanding rim generally indicated at 6. The upstanding rim 6 has a substantially cylindrical base portion 7 which extends substantially perpendicularly from the plane of the base wall 17. The rim 6 also has a prerolled edge portion 8. The edge portion 8 includes an arcuate intermediate section 9 which extends outwardly from the upper end of base portion 7 and which is curved through an arc of close to 180 so that its outer end is opposed to and spaced laterally from said upper end of base portion 7. The edge portion 8 also includes an arcuate tip section 11 which extends from the outer end of section 9 back toward the base portion 7. The tip section 11 is curved on a smaller radius than the portion 9 and is curved through an arc of slightly greater than 90". Thus, a line 12 which is tangent to the outer surface of tip portion 11 at the inner end thereof defines with the outer surface 13 of the base portion 7 an included angle which is close to but which is less than 90. The inner end of tip section 11 is spaced from the surface 13 a distance d (FIG- URE 2a) which is approximately twice the wall thickness of the cylinder 1. In the embodiment here chosen for illustration, the distance d is equal to 0.068 inch, the radius of curvature of the external surface of intermediate section 9 is about .093 inch and the radius of curvature of the external surface of the tip section 11 is .062 inch.

The outside diameter of the base portion 7 of the closure member 2 is substantially equal to the inside diameter of the cylinder 1 so that upon initial assembly said closure member may be telescoped into the cylinder as shown in FIGURE 2. It may be pushed down as far as possible so that, as indicated at 14 in FIGURE 2, the upper end of the cylinder 1 is turned slightly outwardly thereby. However, it is not essential that the closure member 2 be moved so far downwardly within the cylinder 1 that the turnedout portion 14 be formed. In some cases, it may be preferable to telescope the closure member 2 inside the cylinder 1 only so far that the upper edge of said cylinder is directly opposite the end of tip section 11.

A base mandrel 16 is provided in a known manner to engage the base wall 17 of the closure 2 and a clamp 18 is also provided in a known manner to engage the upper surface of said base wall whereby said base wall is firmly gripped between said mandrel and said clamp. The outside diameter of said clamp 18 is only a small clearance distance less than the inside diameter of the base portion 7 so that said clamp may slip easily but snugly into clamping position on said base wall 17.

An annular rolling die 19 encircles clamp 18. The clamp 18 is movable axially with respect to the mandrel 16 in any convenient manner by any suitable means, not shown, and the annular rolling die 19 is likewise reciprocable with respect to the mandrel 16 and the clamp 18 by any convenient means, also not shown, as indicated by the arrows 21. Suitable means for reciprocating clamp 18 and die 19 are well known and understood by those skilled in the art and hence are not shown here.

Turning now to a more detailed examination of the annular rolling die 19, said die has an axial end face which is shaped so as to have a radially inner surface 22, a radially outer surface 28 and a semicircular intermediate surface 23. The inner surface 22 is made as narrow as possible consistent with the strength of the material involved, the width thereof in the particular embodiment here used to illustrate the invention, being of the order of 0.015 inch. What would otherwise be a sharp corner at the intersection of surface 22 and surface 23 is rounded slightly at 24. The surface 23 is semicircular, the center thereof being indicated at 26 on the construction line 27 extending between the surface 22 and the surface 28. The diameter of the semicircular surface 23 is greater than the distance X (FIGURE 2) in order to enable the portion 9 to move along the surface 23 in a rolling manner when the edge 22, as hereinafter further described, moves axially between the upstanding base portion 7 and the clamp 18. In the present embodiment, the diameter of surface 23 is approximately .187 inch. The surface 28 is not critical and may be chosen as convenient to provide sufficient over-all strength for the annular die 19.

Operation The importance of the above-described dimensional relationships further appears upon a tracing of the actions which take place during assembly of the cylinder 1 with the closure member 2.

FIGURE 2 has already been above described and it shows the initial positioning of the cylinder 1, the closure member 2, the mandrel 16, the clamp 18 and the die 19. The die 19 is moved toward the closure member 2, normally downwardly as the parts are usually arranged and as shown in the drawings, and it presently occupies the position shown in FIGURE 3. Here the surface 22 has entered between the base portion 7 and the outer surface of the clamp 18 and this tilts the upper end of cylinder 1 and the base portion 7 radially outwardly. This outward tilting is further assisted by the rounded edge 24 on the die 19. At this point the upper edge 14 of the cylinder 1 and the rim 6 of the closure member 2 have not changed their shape appreciably.

As the die 19 is continued to be moved downwardly, it reaches a position as shown in FIGURE 4 wherein its edge 22 has moved a substantial distance between the upstanding base portion 7 and the outer surface of the clamp 18. The upper part of portion 7 and the radially inner part of intermediate section 9 engage the surface 23 and are bent to conform to the radius of curvature of said surface 23.

As the die 19 moves from the FIGURE 3 to the FIG- URE 4 position the upper end of the cylinder is caused to coil upon itself by the action of the intermediate section 9 and the upper part of portion 7 thereon as they are bent by engagement with surface 23. The resistance of the cylinder 1 to such coiling urges the upper part of portion 7 and the radially inner part of said intermediate section 9 into engagement with the surface 23. Thus, as the parts are moved from their FIGURE 3 to their FIGURE 4 positions, the upper part of portion 7 and the radially inner part of intermediate section 9 will slide along the surface 23 and will be deformed thereby by a die-shaping type of action. At the same time the radially outer part of section 9 is turned back toward the cylinder 1 and the tip portion 11 is moved upwardly through an arc and is disposed, as shown in FIGURE 4, between opposing surfaces of the cylinder 1.

The die 19 continues downwardly until it reaches the position shown in FIGURE 5 wherein the assembly operation is shown as being substantially completed. In this position, the surface 22 is moved to or slightly beyond the bottom of the clamp 18. In so moving, the surface 23 bends the lowermost part of the base portion 7 outwardy and downwardly to form the bulge shown at 29 in FIGURE 5. The remainder of the base portion 7 engages and conforms to the shape of surface 23. During this final motion of the die 19, the intermediate section 9, the tip portion 11 and the upper portion of the cylinder 1 are further rolled and coiled together to form the rigid interlock 3.

If desired, a final and further tightening of the relationship between the upstanding base portion 7 and the adjacent portion of the cylinder 1 may be provided as shown in FIGURE 6 by effecting a slight but still further downward movement of the die 19 by which the surface 22 provides a substantial downward bulge indicated at 29a. This effects a compression of the wall of the cylinder 1 and increases the effectiveness of the interlock.

Thus, in the finished container structure the closure member 2 is rigidly interlocked with the end of the cylinder 1. The rim portion 6 and the end portion of the cylinder 1 therewithin are coiled upon themselves so as to have a substantially spiral configuration and, as will be apparent from FIGURE 5, such spiral has at least one full turn. Indeed the rim 6 has approximately one and one-half turns. The portion 7 in the finished product defines a first, substantially semicircular portion, the section 9 defines a second, substantially semicircular portion which is curved back toward the cylinder 1 and which is curved on a radius of curvature less than the radius of curvature of portion 7 and the tip section 11 is curved through an arc of more than 90 away from the cylinder 1 and on a radius of curvature less than the curvature of intermediate section 9. The end portion of the cylinder 1 is similarly curved and substantially completely fills the rim portion 6.

Modification The foregoing described parts contemplate the assembly of a single, one-piece, closure member with the cylinder 1 and said closure member normally is the bottom of a container. The same technique may be used in various ways, three of which are illustrated in FIG-

URES

7, 8 and 9, for assembling the top of the container.

In FIGURES 7 the

parts

7a, 9a and 11a of a cover mounting ring 31 are identical with the corresponding

parts

7, 9 and 11 above described. The only difference is that instead of there being a solid base wall 17 filling the zone within said ring 31, the part 17a is reversely curved and has a downwardly extending flange 30 which firmly seats against the cylinder 1. The part 17a provides a flange for the support of the cover member 32.

Said cover member 32 has a central portion 33, an upstanding rim 34 and a rolled upper edge 36. Said upstanding rim 34 and the rolled upper rim 36 may be made in any convenient manner including, if desired, the technique above described in connection with rolling the upper edge of the closure member 2.

In FIGURE 8, the parts 712, 9b and 11b of the rim 37 again are identical with the corresponding

parts

7, 9 and 11 above described. Here, however, the inner portion of the part 7b is rolled as indicated at 38 to provide a rim upon which to receive the cover. The cover may be of the form shown at 32 in FIGURE 7 or of the form shown at 39 in FIGURE 8. Referring to cover 39, the upstanding flange 41, corresponding to the flange 34 in FIGURE 7, is rolled inwardly at 42 as shown in order to cooperate with the lower end of a container made as shown in FIGURE 1 for stacking purposes. A reinforcing rib 43 may be provided in the cover 39 if desired.

In FIGURE 9 the parts 7c, and of the rim 46 are identical with the corresponding

parts

7, 9 and 11 above described. The rim 46 has an intermediate flat wall portion 47 and a rolled, inner edge portion 48. The cover 51 includes a rolled edge portion 52 whose uppermost point is offset upwardly a small distance, e.g., .125 inch, from the uppermost point on the rim 46. The cover 51 has a planar wall portion 53 which is of substantially the same width as the diameter of the edge portion 48 and which rests thereon. The cover also has a second wall portion 54 which extends at an angle of slightly greater than 90 to the wall portion 53 so that it tapers slightly toward the opposite end thereof. The wall portion 54 is received within the rolled edge 52 and snugly engages same. As a result of such engagement, an intermediate part of the wall portion 54 is bulged inwardly as indicated at 56 so that the cover 51 is securely but releasably engaged by the rim 46. The cover 51 has a central wall portion 57 which closes off one end of the cylinder 1. The rolled edge portion 52 of the cover 51 is positioned so that another container can be stacked thereon, the other container being indicated at E in FIG- URE 9.

In FIGURE 10 is shown a modification of the assembly apparatus wherein the mandrel 16 and the clamp 18 have axially aligned,

annular grooves

61 and 62 on the opposite faces thereof adjacent the peripheries thereof, which grooves are substantially semicircular in cross section. When the mandrel 16 and the plunger 18 are adjacent each other, the

grooves

61 and 62 mate and almost completely encircle the rolled edge portion 48 of the rim 46 while the die 19 is being moved to effect interlocking of the cylinder 1 and the remainder of said rim. This insures that the inside diameter of the rim 46 is uniform so that the cover 51 can snugly engage same and effectively close off the end of the cylinder.

Alternate structure for container bottom Referring to FIGURE 11, a fragment of an alternate container bottom closure member 102 is shown partially inserted into the open bottom end of but not yet attached to an inverted container cylinder 101 which for purposes of illustration may be considered essentially similar to the cylinder 1 of FIGURES l and 2. The closure member 102 may be of the same material as the closure member 2 of FIGURE 1. The closure member 102 has a base wall 117 and a rim portion 106 having a cylindrical base portion 107 extending essentially perpendicularly upwardly from a bend 138 in the base wall 117 to a prerolled edge portion 108. The prerolled edge portion 108 extends outwardly through an angle of approximately 90 and at an exterior radius corresponding to that of the concave surface of an annular rolling die 119, said annular rolling die being in the embodiment illustrated identical to the die 9 of FIGURE 2. Because of the identical construction of said dies, the same reference numerals with the suffix a added will be used to describe parts of the die 119 as were used to designate corresponding parts of the die 9.

The base wall 117 of the closure member 102 is supported upon a base mandrel 116 which is snugly received within the cylinder 101. The base mandrel 116 has a hemicircular, annular groove 131 in its upper surface adjacent the circumferential wall thereof. The axial extent of the radially outer wall of the groove 131 is reduced as shown at 132 by any convenient means such as grinding whereby the minimum thickness of the wall between the annular groove 131 and the radially outer surface of the base mandrel 116 is increased sufiiciently that breakdown of said wall during normal usage will not occur. In the embodiment here chosen for illustration, said minimum width of the wall is approximately .010 inch whereby the distance between the upper surface of said wall and the upper surface of the mandrel 116 is approximately .028 inch. A clamp mandrel 118 is received through the rim 6 and rests upon the base wall 117 of the closure member 102. The lower radial surface of the clamp mandrel 118 has an annular hemicircular groove 136 cut therein adjacent the peripheral Wall thereof. The radially outer wall of the groove 136 is reduced in axial extent as shown at 137 by any convenient means such as grinding so that the minimum thickness of the material between the groove 136 and the outer surface of the peripheral wall of the clamp mandrel 118 is increased to minimize breakdown thereof. Said minimum thickness may be approximately .010 inch and the distance between the radially outer termination of groove 136 and the upper face of the base wall 117 is approximately .028 inch. The clamp mandrel 118 is of lesser radius than is the base mandrel 116 by at least the thickness of the cylindrical base portion 107. The radius of curvature of the annular groove 136 is less than that of the annular groove 131 whereby the radially inner edge of the groove 136 lies radially outwardly of the radially inner edge of the groove 131. Using for example only and not intending limitation, a closure member 102 having a wall thickness of approximately .015 inch and a cylinder 101 having a wall thickness of approximately .045 inch, a rolling die having a rolling sur face radius of approximately .094 inch may be used. Satisfactory radii for the

grooves

136 and 131 have been found to be approximately .078 inch and .090 inch respectively.

Operation of alternate structure Assuming the closure member 2 to be inserted in the cylinder 101 and the m-andrels 1'18 and 116 to be in place essentially as shown in FIGURE 11, the annular rolling die 119 is moved downwardly to engage the prerolled edge portion 8 of the closure member 102 whereby the prerolled edge portion 108 comes into essentially continuous contact with the concave rolling surfaces 23a of said annular die (FIGURE 12). Continued downward movement of the rolling die 119 causes the prerolled edge portion 108 and cylindrical base portion 107 of the closure member .102 to move downwardly therewith whereby the bend 138 joining the base wall 117 with the base portion 107 moves downwardly to contact the surface of the annular groove 131 near the radially outer extremity thereof. Such downward movement also causes the material of the base wall 117 to be bent downwardly as shown at 139 at the radially inner edge of the groove 131. The cylinder 101 is restrained from downward movement by any convenient, preferably resilient, means not shown and therefore does not move downwardly with the base portion 107. In their positions shown in FIGURE 12, the vertical distance between the bend 138 and the top of the prerolled edge portion 108 is preferably W inch and t he yertical distance bet-ween the edge 1 14 of the cylinder 101 and the top of the edge portion 8 is preferably /s inch. These dimensions will be understood to be illustrative only and not limiting.

As the annular rolling die 1'19 continues moving downwardly from its position of FIGURE 12, it exerts an essentially continuous down-ward force on the edge portion 108 and the base portion 107 whereby the material of the base wall 117 radially outward of the bend 139 is moved essentially downwardly into conformity with the surface of the groove 131 (FIGURE 13) whereby an annular groove 141 is formed in the base wall 117. During this process, some relative movement takes place between the stationary cylinder 101 .and the downwardly moving base portion 107, which relative motion ceases when the material of the base wall 117 radially out-ward of the bend 139 conforms to the surface of the groove 131. Simultaneously with or shortly after the reshaping of the base wall 117 as hereinabove described, continued downward movement of the rolling die 119 causes relative movement between the rolling surface 23a of said die and the surface of the rim 106 whereby said rim is rolled into its position of FIGURE 13.

Shortly after rolling of said rim commences, the rolling die 1 19 will move downwardly past the level of the end 114 of the cylinder 101 whereby the wall of said cylinder will be rolled with the rim 106 into its position of FIG- URE 13. When the end 112 of the rim 106 reaches its position of FIGURE 13 said end 112 tends to dig into the outside surface of the wall of the cylinder 10d and to become interlocked therewith. Thus, continued downward move-ment of the rolling die 1 19 from its position of FIG- U R'E 13 will tend to make the end 112 become even more securely interlocked in the material of the wall of the cylinder 101. As the rolling die 119 reaches its lowermost position (FIGURE 14), the upper part of the base portion 107 and the edge portion 108 are tightly wound around the upper portion of the wall of the cylinder 10'1 producing compressive forces of considerable magnitude between the contacting faces of said wall and said portions and thereby an effective seal therebetween. The incursion of the end 1 12 into the wall of the cylinder 10 1 adds to the effectiveness of said seal whereby leakage from the interior of the container is effectively prevented.

It has been noted in testing this embodiment, that the rolling of a rim having an edge portion that is parallel through only a relatively small angle, such as achieves the desired finished rim consthuction even when the wall thickness of the container cylinders varies relatively widely from cylinder to cylinder. Thus, it has been found that a rim construction method employing a small angular preroll is more tolerant of container wall variation than is a similar method employing a relatively large angular preroll. Though the cause of this effect is not yet precisely known it has been hypothesized that the angularly earlier overcoming of external and internal starting frictional forces between and within the involved elements produces a more smoothly continuous rolling of the rim where a smaller angular preroll is employed whereby the tolerance to disruptive effects is increased.

It should be noted that the rolling of the rim 106 and the formation of the groove 141 although described together hereinabove for convenience in description, may if desired be performed separately whereby a rim 106 is so formed on a container not including a base wall having therein a groove 1 11 or whereby a groove 14-1 is formed in the base wall of a container during the formation of a rim thereon of a type different from the rim 106.

The presence of the groove 141 near the radially outer edge of the base wall 117 prov-ides a receptacle for receiving thereint-o the rim of a cover for a second container whereby a first container may rest securely upon the top of said second container in an essentially interlocked fashion wherein relative sliding movement between the adjacent radialfaces of thelstackedrcontainers.isprevented. A cover capable of nesting in a groove 14 1 may 9 be made with a rolling die similar to the die 11-9 but having a circumference corresponding to that of the groove 141 whereby the rim of said cover may be inserted into said groove.

Alternate structure for container top FIGURES 15 and 16 disclose means for completing the rolling of the pre'rolled bead 1 48 lying against and inside of a wall on a cylinder 101a near the top edge thereof, said head being integral with a rolled rim not shown which may be similar to the rim 106 of FIGURES 11 through 14. The bead 148 may be employed as a rest against which the rim of a suitable rimmed container cover such as discussed hereinabove might rest. The preformed bead 148 preferably has an outside diameter equal to that of the groove 131a of the die 1 16a which is preferably identical with the die 116 (FIGURES 11 through 14). A clamp mandrel 1 18a, preferably similar to the clamp mandrel 118 (FIGURES 1 1 through 14) is in the closing step preceding the descent of the rolling die 119, driven downwardly on the bead 148 whereby to move the end portion 149 thereof downwardly essentially to its position of FIGURE 16. Thereafter, a rim such as the rim 106 may be formed on the end of the base portion 107a in the manner hereina-bove discussed in connection with FIGURES 11 through 14.

Thus, it is apparent that the same base mandrel 116, clam-p mandrel 118 and rolling die 119 may be utilized to form a closure panel on the lower end of a container as is used to form an integral rim and cover stop bead for the upper end of said container. This forming of both top and bottom units of the container on a single machine will obviously facilitate the assembling of containers under any circumstances but will be especially useful where such assemblies are short runs of a given size or are done in the field. Further, the forming of the nesting parts of the top and bottom units in a single set of (lies will facilitate the accurate nesting, and thereby stacking, of successively made containers.

While specific embodiments have been here utilized to illustrate the invention, it will be recognized that the invention will be applicable to a wide variety of containers and the hereinafter appended claims shall be so interpreted excepting as their terms may expressly require otherwise.

What is claimed is:

1. A container construction, comprising:

a cylindrical member defining the side wall of a container, said cylindrical member being formed of fibrous material;

a one-piece rim having the general appearance of a figure eight in cross-section and disposed transversely across one end of said cylindrical member, said rim having an intermediate wall portion of substantially the same external diameter as the internal diameter of said cylindrical member and which is snugly telescoped within said one end of said cylindrical memher, said rim having an outer wall portion which merges smoothly with and extends radially outwardly from said intermediate wall portion and then downwardly and back toward said member, said outer wall portion being curved through an arc of at least about 360 and being rigidly interlocked with an end portion of said cylindrical member and forming an outer ring projecting radially outwardly from the outer surface of said cylindrical member, said rim having an inner wall portion extending radially inwardly and then upwardly and back toward said cylindrical member, said inner wall portion being curved through an arc of at least about 360 and forming an inner ring which projects radially inwardly from the inner surface of said cylindrical member, said inner and outer rings being disposed in at least partially overlapping relation in an axial direction along said cylindrical member so that they provide reinforcement for each other in a radial direction, said rim also having an upwardly opening groove between said rings.

2. A container construction according to claim 1, in which the uppermost point on said inner ring is ofiset vertically downwardly from the uppermost point on said outer ring.

3. A container construction according to claim 1, in which said inner and outer rings are concentric with each other and with said cylindrical member.

References Cited by the Examiner UNITED STATES PATENTS 931,233 8/1909 Stieble 2295.6 1,590,748 6/1926 Hulber't 2295.6 1,753,929 4/1930 Hul'bert 229--5.7 2,082,701 6/1937 Kuelfner 2295.6 X 2,874,888 2/1959 Horning 229-5 .6

FOREIGN PATENTS 7,571 1903 Great Britain.

GEORGE O. RALSTON, Primary Examiner.

Claims

1. A CONTAINER CONSTRUCTION, COMPRISING: A CYLINDRICAL MEMBER DEFINING THE SIDE WALL OF A CONTAINER, SAID CYLINDRICAL MEMBER BEING FORMED OF FIBROUS MATERIAL; A ONE-PIECE RIM HAVING THE GENERAL APPEARANCE OF A FIGURE EIGHT IN CROSS-SECTION AND DISPOSED TRANSVERSELY ACROSS ONE END OF SAID CYLINDRICAL MEMBER, SAID RIM HAVING AN INTERMEDIATE WALL PORTION OF SUBSTANTIALLY THE SAME EXTERNAL DIAMETER AS THE INTERNAL DIAMETER OF SAID CYLINDRICAL MEMBER AND WHICH IS SNUGLY TELESCOPED WITHIN SAID ONE END OF SAID CYLINDRICAL MEMBER, SAID RIM HAVING AN OUTER WALL PORTION WHICH MERGES SMOOTHLY WITH AND EXTENDS RADIALLY OUTWARDLY FROM SAID INTERMEDIATE WALL PORTION AND THEN DOWNWARDLY AND BACK TOWARD SAID MEMBER, SAID OUTER WALL PORTION BEING CURVED THROUGH AN ARC OF AT LEAST ABOUT 360* AND BEING RIGIDLY INTERLOCKED WITH AN END PORTION OF SAID CYLINDRICAL MEMBER AND FORMING AN OUTER RING PROJECTING RADIALLY OUTWARDLY FROM THE OUTER SURFACE OF SAID CYLINDRICAL MEMBER, SAID RIM HAVING AN INNER WALL PORTION EXTENDING RADIALLY INWARDLY AND THEN UPWARDLY AND BACK TOWARD SAID CYLINDRICAL MEMBER, SAID INNER WALL PORTION BEING CURVED THROUGH AN ARC OF AT LEAST ABOUT 360* AND FORMING AN INNER RING WHICH PROJECTS RADIALLY INWARDLY FROM THE INNER SURFACE OF SAID CYLINDRICAL MEMBER, SAID INNER AND OUTER RINGS BEING DISPOSED IN AT LEAST PARTIALLY OVERLAPPING RELATION IN AN AXIAL DIRECTION ALONG SAID CYLINDRICAL MEMBER SO THAT THEY PROVIDE REINFORCEMENT FOR EACH OTHER IN A RADIAL DIRECTION, SAID RIM ALSO HAVING AN UPWARDLY OPENING GROOVE BETWEEN SAID RINGS.