Cup lid manufacturing process

Abstract

A substantially crimpless and monolithic paperboard container lid and method of making same is provided. The lid comprises a single contiguous molded paperboard body configured to conformingly couple to a top periphery of a container for covering the container's opening. The body includes a sealing ring located adjacent the body's periphery. The sealing ring includes a sealing channel composed of a radiused cross-section that extends to a tangent ring terminating with a tab ring. The radiused cross-section and tangent ring assist providing a snug fit between the lid and the container. Despite being made from paperboard, the lid does not include one or more substantial crimps in the sealing ring. Having no substantial crimps, the lid fits onto the container and prevents fluid from leaking between the container's periphery and the lid.

Claims

1. A substantially crimpless and monolithic paperboard container lid comprising: a single contiguous molded paperboard body of a single paperboard blank conformingly attachable to a top periphery of a container for covering the container's opening; wherein the paperboard body comprises a sealing ring located adjacent the body's periphery; wherein the sealing ring includes a sealing channel composed of a radiused cross-section; wherein the radiused cross-section extends to a tangent ring terminating with a tab ring; wherein the radiused cross-section and tangent ring are configured to at least partially wrap around the top periphery of the container; wherein the radiused cross-section has a radius greater than 180 degrees to assist providing a snug friction fit between the paperboard container lid and the container; wherein the paperboard body does not include one or more substantial crimps in the sealing ring; wherein having no substantial crimps on an inside surface of the sealing ring, the paperboard container lid selectively fits onto the container and prevents fluid from leaking between the container's periphery and the paperboard lid; and wherein the tab ring flares outward from the tangent ring providing a lip for grasping the paperboard container lid.

2. The substantially crimpless and monolithic paperboard container lid of claim 1, wherein the lid's size, along with the sealing channel accommodates the circumference of the bottom of the container to assist in allowing the lid to serve as a stackable surface for additional containers.

3. The substantially crimpless and monolithic paperboard container lid of claim 1, further comprising an emboss formed on a surface of the lid assists in adding strength to the lid.

4. The substantially crimpless and monolithic paperboard container lid of claim 1, wherein the shape of the paperboard container lid simulates the shape of a conventional plastic lid.

5. The substantially crimpless and monolithic paperboard container lid of claim 1, wherein a poly coating is applied to one surface of the paperboard container lid.

6. The substantially crimpless and monolithic paperboard container lid of claim 5, wherein a clay coating is applied to a surface of the paperboard lid opposite the surface with the poly coating to accommodate printing of indicia on the lid.

7. The substantially crimpless and monolithic paperboard container lid of claim 1, wherein the paperboard thickness is from about 0.012 inch to about 0.030 inch.

8. The substantially crimpless and monolithic paperboard container lid of claim 1, wherein the shape of the paperboard can be modified to accommodate the shape of the sealing ring of the container.

9. The substantially crimpless and monolithic paperboard container lid of claim 1, wherein the radiused cross-section of the sealing ring can be either round, square, rectangular, oval, or oblong and configured to conformingly fit the periphery of the container.

10. A substantially crimpless and monolithic paperboard container lid comprising: a single contiguous molded paperboard body of paperboard blank conformingly attachable to a top periphery of a container for covering the container's opening; wherein the paperboard body comprises a sealing ring located adjacent the body's periphery; wherein the sealing ring includes a sealing channel composed of a radiused cross-section; wherein the radiused cross-section extends to a tangent ring terminating with a tab ring; wherein the radiused cross-section and tangent ring are configured to at least partially wrap around the top periphery of the container; wherein the radiused cross-section has a radius greater than 180 degrees to assist providing a snug friction fit between the paperboard container lid and the container; wherein the paperboard body does not include one or more substantial crimps in the sealing ring; wherein having no substantial crimps, the paperboard container lid selectively fits onto the container and prevents fluid from leaking between the container's periphery and the paperboard lid; and wherein the tab ring flares outward from the tangent ring providing a lip for grasping the paperboard container lid.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) The present disclosure will be described hereafter with reference to the attached drawings which are given as non-limiting examples only, in which:

(2) FIG. 1 is a perspective view of a fluid container with a paperboard lid coupled thereto;

(3) FIG. 2 is a perspective cut-away view of the fluid container in paperboard lid of FIG. 1;

(4) FIGS. 3a-c are perspective, top, and side cross-sectional views of a formed paperboard lid;

(5) FIG. 4 is a top view of a circular blank prior to being formed into a container lid;

(6) FIG. 5 is a perspective view of a paperboard lid press;

(7) FIG. 6 is a cross-sectional view of the press of FIG. 5 in an open position;

(8) FIG. 7 is another cross-sectional view of the press of FIG. 5 with a male body and draw ring lowering against a support;

(9) FIG. 8 is a cross-sectional perspective view of the lower half portion of the press of FIG. 5;

(10) FIG. 9 shows both the male body lowered against the support, but also slides laterally drawn in against the support and the male body to form the container lid from the blank;

(11) FIG. 10 is a perspective cross-sectional view of the press in the position discussed with respect to FIG. 9;

(12) FIGS. 11a and b are a side cross-sectional and detail views of the press demonstrating how the container lid is stripped off;

(13) FIG. 12 shows a detail perspective cut-away view of pressure ring and slides; and

(14) FIG. 13 is a perspective detail wire view of the pressure ring, slides, and a blank.

(15) Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates embodiments of the container lid and method, and such exemplification is not to be construed as limiting the scope of the container lid and method in any manner.

DETAILED DESCRIPTION OF THE DRAWINGS

(16) Perspective and cut-away views of fluid container 2, such as a coffee or soup cup and a paperboard lid 4 coupled thereto, are shown in FIGS. 1 and 2, respectively. In this illustrative embodiment, paperboard lid 4 conformingly attaches to container 2. As particularly shown in FIG. 2, an embodiment of container 2 includes a sealing ring 6 that extends around the periphery of opening 8. Illustratively, sealing ring 6 has a cylindrical cross-section. It is appreciated, however, that the periphery of opening 8 can have a ring of any variety of cross-sections and that lid 4 comprises a sealing channel 10 configured to conformingly fit onto ring 6 in a manner like that shown in FIG. 2. It will also be appreciated that the size of lid 4 along with sealing channel 10 can be configured to accommodate the circumference of bottom 12 of container 2. This assists in allowing lid 4 to serve as a stackable surface for additional containers 2, the concept of which is known by those skilled in the art. Also in this illustrative embodiment of lid 4, emboss 14 formed on surface 24 assists in adding strength and rigidity to the lid 4.

(17) Perspective, top, and side cross-sectional views of a formed paperboard lid 4 are shown in FIGS. 3a-c. The configuration of lid 4 may simulate that of conventional plastic lids. Paperboard lid 4 illustratively includes a poly coating on one side and may or may not have a clay coating on the other side. The poly coating makes the paper liquid resistant while the clay coating allows printing of customer information or other indicia on lid 4. Paper thickness for lid 4 may vary from about 0.012 to about 0.030 thick, for example.

(18) As can be appreciated from these views, the illustrative embodiment includes sealing channel 10 composed of a radius top 18 illustratively extending to a tangent 20 that terminates with a tab 22. Radius top 18 and tangent 20 wrap around sealing ring 6 located at the peripheral rim of cup 2. Radius top 18 in this embodiment illustratively includes a radius greater than 180 degrees. Tangent 20 assists extending radius top 18 over ring 6. Tab 22 flares outward from tangent 20 providing a contact surface or lip for removing lid 4 from cup 2. It is further appreciated that channel 10 is sized to fit over ring 6 providing a snug friction fit between lid 4 and cup 2, similar in character to conventional mating between paper cups and plastic lids. It will also be appreciated that the radius or cross-section of cup 18 can be modified to accommodate the shape of sealing ring 6 on cup 2. For example, in alternate embodiments, the cross-section of sealing ring 6 may be square, rectangular, oval, or oblong. Top 18 can similarly be conformingly modified to fit over those cross-sections.

(19) A top view of an illustrative embodiment of lid 4 as a circular blank is shown in FIG. 4. In an embodiment, the blank forming lid 4 can be a circular sheet of paper or paperboard having a diameter of about 4.142 inches. It is appreciated, however, that the thickness and diameter can vary depending on the material and requisite size and shape requirements of the mating cup.

(20) In an illustrative embodiment, lid 4 in blank form is pre-scored. A scoring tool can be used to form grooves 26 into lid 4 that are approximately 3/16 to inches long and about 0.002 to about 0.005 inches deep. There may be anywhere from about 24 to about 60 scores positioned radially and extending the circumference of blank 4, such as grooves 26 shown in FIG. 4. In another illustrative embodiment, the blank form of lid 4 may include a perforated pattern 28 formed in its surface. The perforated material can be removed to create a spout when the lid 4 is in final shape, similar to plastic cup lids. The perforated area may also include a tab to help pull off the spout. It is appreciated that other embodiments of lid 4 may include grooves having different thicknesses, depths, and quantities.

(21) The views in FIGS. 5-13 show machinery and processes for making the paper blank into lid 4. A perspective view of press 30 is shown in FIG. 5 capable of making paperboard lid 4. Press 30 illustratively comprises a male flange 32 located over draw ring 34 and knock down ear 36. A blank stop 38 extends from pressure ring 40 and pressure ring 40 receives draw ring 34. Cylinder ears 42 and 44 flank pressure ring 40 and are configured to receive fluid cylinders 46 and 48. Shoulder bolts 50 and 52 connect female flange 54 to pressure ring 40 with base 56 sandwiched in between.

(22) FIGS. 6-10 are a series of progression views showing how press 30 operates to form lid 4. As shown, particularly in FIG. 6, press 30 is in the open position with draw ring 34, male body or die 58, knock down ears 36, and male flange 32 all suspended above the paper blank form of lid 4 seated on female pressure ring 40. Stop 38 is located on pressure ring 40 to hold the blank onto press 30.

(23) Also shown in this view is female flange 54 supporting cavity support 64 via springs 66 and base 56. In an illustrative embodiment, fasteners 68 are disposed through base 56 and extend into channels 90 of support 64. Slide 70, or a plurality of slides 70, is (are) illustratively positioned around the periphery of support 64 with springs 72 biasing thereagainst, as illustratively shown. It is appreciated that slides 70 may be composed of any number of slides members. (See FIGS. 12 and 13.) It is further appreciated that base 56 engages slide 70 on an angled plane 74 relative to the axis of movement 76 of male body 58. In the illustrative embodiment, the angle is about 30 degrees. It is appreciated however, that other lid designs may employ a different angle.

(24) In this embodiment, support 64 includes a surface 80 that illustratively includes a channel surface 82 that receives lid 4 to form emboss 14. (See FIGS. 1 and 2.) A surface 84 of slides 70 may also include a contact surface that forms at least a portion of sealing channel 10. It is appreciated that the precise shapes of these mold surfaces can be changed to form the desired shape of the lid 4. Air cylinders 46 and 48 raise pressure ring 40 to exert pressure on lid 4 and draw ring 34. This embodiment also includes plunger component 85 with surface 87 to form emboss 14 on lid 4 as shown in FIGS. 1-3.

(25) The view shown in FIG. 7 depicts male draw ring 34 and male body 58 lowering against support 64 and pressure ring 40 sandwiching lid 4 therebetween. It is appreciated, as shown in this illustrative embodiment, that surface 86 of male body 58, and surface 87 of plunger component 85 correspond to surfaces 80, 82, and 84. As shown in this view, lid 4 is sandwiched between the female support 64 and male body 58. Illustratively, slides 70 are not yet being drawn towards lid 4 to fully compress it into shape.

(26) A cross-sectional perspective view of press 30, shown in FIG. 8, removes male body 58, ring 34, knock down ear 36, and male flange 32 to better depict the positioning of lid 4 within cavity 83 collectively made from ring 40, slides 70, and support 64. This view also shows stop 38 that holds blank 4 in position until it is trapped between draw ring 34 and pressure ring 40.

(27) The cross-sectional view shown in FIG. 9 depicts not only the male and female mold components compressed to form lid 4, but now a lateral compressive force is applied to lid 4 via slides 70.

(28) As shown therein, flange 32 extends downward in direction 88 compressing springs 66 (not shown, see FIG. 6). This forces male body 58 and plunger 85 to also move in direction 88 to engage support 64. As shown in this view, lid 4 sandwiched therebetween is not only subjected to a compressive force from support 64 and body 58, but is also subjected to lateral forces from slides 70 helping form lid 4's three-dimensional shape. Support 64 is pushed downward in direction 88, which by virtue of its downward movement forces slide 70 down on angle surface 74. Channels 90 within support 64 are sized to allow fastener 68 to restrict the travel of support 64. (Compare the relative positions of fasteners 68 in channel 90 between FIG. 6 and FIG. 9.) This movement of support 64 causes a compressive force by slides 70 against the bias of springs 72. Under non-compressive conditions, springs 72 keep slides 70 away from support 64 allowing loading and unloading of lid 4. Movement of support 64 overcomes that bias force and the surfaces 84 of slides 70 conform to surface 86 of male body 58 to fully form lid 4's final shape.

(29) A cross-sectional perspective view of press 30 is shown in FIG. 10. The components of press 30 in this view are in the same position as that shown in FIG. 9. This view, however, depicts how slides 70 are being compressed against support 64. Lid 4 is sandwiched between slides 70, male body 58, and support 64 forming the final lid shape.

(30) The perspective elevation view shown in FIG. 11a depicts how lid 4 is stripped off of male body 58 once fully formed. Male body 58 retracts inside draw ring 34. Because a portion of lid 4 extends between draw ring 34 and pressure ring 40, it is held in place. Lid 4 is pried from male body 58 and is left sitting in cavity 83. In addition, slides 70 expand as female support 64 moves upward because of bias from springs 66. This in turn causes the slides 70 to move up and back thereby lowering base 56 and allowing bias of springs 72 to push slides 70 away from support 64.

(31) The detail view shown in FIG. 11b further depicts male body 58 being removed from lid 4 with draw ring 34 and pressure ring 40 continuing to hold lid 4 in place. This view also shows slide 70 spaced apart from lid 4 after formation.

(32) FIGS. 12 and 13 are detail perspective views showing pressure ring 40, paper blank 4, and slides 70. In this view, blank 4 is shown in transparent view to show slides 70 positioned underneath. When male body 58 depresses blank 4 into cavity 83, draw ring 34 will hold blank 4 against pressure ring 40. As slides 70 close, blank 4 will be molded into the lid. There is a risk that a portion of blank 4 will be caught in a seam 92 located between adjacent slides 70, as shown. If a substantial enough amount of paper from blank 4 gets caught in seam 92, a crimp in the lid will be formed which not only detracts from the physical appearance of the lid, but also serves as a break in any seal created between the lid and the cup. Losing the seal between the cup and the lid can be detrimental if fluid, particularly hot fluid such as coffee, contacts the seal between the lid and the cup and is allowed to seep out. It is contemplated in an embodiment, however, that a minor amount of crimp may still occur even if using the pressure and draw rings, but that crimp is nominally sized and does not affect the sealing of the lid onto the cup.

(33) The view shown in FIG. 13 is similar to that shown in FIG. 12 except that pressure ring 40 and blank 4 are shown in transparent view to better illustrate how the four slides 70 are positioned with respect to each other and the seam or gap 92 exist prior to slides 70 being drawn towards each other during the molding process.

(34) Although the present disclosure has been described with reference to particular means, materials, and embodiments, from the foregoing description, one skilled in the art can easily ascertain the essential characteristics of the present disclosure and various changes and modifications may be made to adapt the various uses and characteristics without departing from the spirit and scope of the present invention as set forth in the following claims.