FIELD OF THE INVENTION
This invention relates to the field of winding cores, in particular, winding cores for use with paper, paper board, or other sheet material.
BACKGROUND OF THE INVENTION
Sheet material, such paper, fabric, plastic sheeting and the like is typically wound onto paper cores. For example, in the direct mail industry, paper mills wind their stock forms onto paper board cores for shipment to a direct mail printing facility. The forms come in various sizes; generally 25,000 forms or pages per roll. The press department then punches pin feeds into the paper. The press department then prints anything that may be consistent on the form such as letter head or form numbers for any given customer. During this process the form is unwound from the shipped roll and then wound onto another paperboard core. The core that came with the paper is customarily discarded when there is still some paper left on it . . . any where from 1″ to 3″ thickness of paper and then the core and paper is customarily discarded.
After the press punches pin feeds, prints letter head and rewinds the sheet forms, the roll is transferred to the laser printing department where the roll is unwound and rewound onto yet another core during the personalization process. (Names, addresses, phone numbers, letter information, etc.)
A direct mail facility that produces between 30 or 40 million names/addresses per month goes through between approximately 2,500 to 3,500 cores that are thrown into bins for recycling. Furthermore, there are more than 2,000 rolls with cores on the production floor waiting to go through the process at any given time.
Currently, winding cores are made of paper board and paper products. Their reuse is limited to several times, recycling and/or refurbishing the core so that it can be again used for winding material thereon. Double-sided tape is wrapped around the core in a “candy cane style” to adhere the sheet material to the core. Once the paper is completely wound onto the core, wooden plugs are pounded into the ends of the core to prevent it from collapsing from the weight of the load that was would upon it if the rolled material stays on the core for a considerable amount of time.
There is not found in the prior art a reusable core that will eliminate the need to throw away these rolls.
SUMMARY OF THE INVENTION
It is an aspect of the invention to provide a reusable core that is suitable for having paper or other sheet material wound thereon. A multi-sectioned core is provided that is easily assembled. Interlocking sections that provide a pivot are held together by a sliding rod inserted therein. By removing one rod between adjacent interlocking sections one of which is the key section, the core collapses thereby permitting easy removal. The sheet material is held onto the core by means of a strip of double sided tape until the core is wound several times to keep the sheet material firmly in place.
This aspect of the invention are not meant to be exclusive and other features, aspects, and advantages of the present invention will be readily apparent to those of ordinary skill in the art when read in conjunction with the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an end view of the preferred embodiment of the reusable collapsible core in accordance with the invention.
FIG. 2 is an isometric view of the core with one ton removed showing how the core is able to be collapsed; this view shows an alternative embodiment with four sections forming the core.
FIG. 3 is isometric bottom view of one section of the core.
FIG. 4 is an end view of one section of the core.
FIG. 5 is a top view of the core.
FIG. 6 is a cross-sectional view of one section of the core along line BB as shown in FIG. 5.
FIG. 7 is a cross-sectional view of one section of the core along line AA as shown in FIG. 5.
FIG. 8 is a detailed view of the snap ring rod interlocking assembly.
FIG. 9 is a detailed view of the quick release rod interlocking assembly.
FIG. 10 is an isometric view of the reusable collapsible core showing the assembled four sections.
DETAILED DESCRIPTION OF THE INVENTION
The invention is a reusable collapsible core that is useful for winding paper forms or other sheet material thereon. The core is preferably made of plastic but metal or hard rubber could also be used. The life span will be measured in years with little or no maintenance required.
As shown in FIG. 1, invention 10 is assembled from three sections. First arcuate section 12 is substantially the same as second arcuate section 14. Note that arc length 53 of first arcuate section 12 is substantially the same length as the arc length 55 of second arcuate section 14. Also, note that arc length 51 of third section 18 is substantially less than the arc lengths 53, 55 of sections 12, 14 respectively. Each section can be manufactured from the same material or different materials. As noted above, plastic is the preferred material which is either injection molded or extruded. The assembled core is designed to allow for expansion and contraction of the cylinder outside diameter for the purpose of both allowing for the maximum cylinder circumference while winding rolled sheet materials and to allow for collapsing the invention for removal so that it can be used again. Three rod assemblies, a quick release rod assembly and two snap ring rod assemblies (described in detail below) are positioned through openings 17 to lock each section to its adjacent section as shown. Once the quick release rod assembly is removed, third section 18 is easily collapsed, thus collapsing the core and invention 10 can be removed from waste sheet material that is wound thereon as shown in FIG. 2.
FIG. 2 shows an alternative embodiment of the invention using four arcuate sections, each being substantially the same including arc lengths.
The interior of each section of invention 10 is provided with a plurality of detents 43 as shown in FIGS. 2 and 3 which permit increase the structural integrity of the core without adding additional mass or cost of material. As shown, each arcuate section is provided with interlocking joint assembly 16 which meshes with an interlocking joint assembly 16 of an immediately adjacent section. Openings 17 in each interlocking joint assembly 16 are aligned to permit a rod to pass therethrough. When joined together, the sections form a cylindrical tube as shown in FIG. 1.
As shown in FIG. 4, each section provides a portion of the circumference which corresponds to a mandrel (not shown) which invention 10 is placed thereon. Each arcuate section provides an arc of a circle having an outer radius R1 and an inner radius R2. Radius R2 is selected to fit onto the printing mandrel that is being used. The difference between R1 and R2 is selected based on the strength that the core must provide in to prevent it from collapsing until quick release rod assembly 44 (shown in FIG. 9) is removed from opening 17 so that invention 10 may be easily withdrawn from the remaining sheet material wrapped around the core. Then, the sheet material, usually paper, is discarded and invention 10 may be used again.
Referring to FIG. 5, a top of invention 10 is shown using first arcuate section 12 as a representative example. Second arcuate section 14 is substantially the same and third arcuate section 18 is likewise except that its arc length is substantially shorter. Together, arcuate sections 12, 14, and 18 provide the core when attached together with two snap ring rod assemblies 23 (shown in detail in FIG. 8) and one quick release rod assembly 44 (shown in FIG. 9).
As shown in FIG. 6, the cross-sectional view of the alternative embodiment taken along line BB noted in FIG. 5, shows the plurality of detents 43 which to make each arcuate section egg-crate shaped in appearance as viewed from the inside. Each snap ring rod assembly 23 and one quick release rod assembly 44 is inserted through openings 17 in the respective sections to hold each section in place while sheet material (not shown) is wound onto surface 19. FIG. 7 shows a similar cross-sectional view taken along a different section line AA in FIG. 5.
Referring to FIG. 8, a detail view of pin assembly 16 is provided. Snap ring rod assembly 23 is fed into openings 17 of interlocking sections and then held firmly in place via a snap ring 25 which fits into circumferential channel 29. Snap ring 25 is easily removed using snap ring pliers (not shown) which are well known in the art. While this is the preferred method of holding snap ring rod assembly 23 in position so that the held sections can pivot with respect to one another, other mechanisms well known in the art could be used as well.
Referring to FIG. 9, a detailed view of the quick release rod assembly 44 is shown. Assembly 44 is a rod that has a cross-section corresponding to opening 17 dimensions which preferable about 3/16 inches in diameter. A bend of about inch long at one end serves as a handle so that the assembly 44 can easily be inserted into openings 17 of the key arcuate section 18 and first arcuate section 12 to attached the two together and then quickly removed by pulling on the handle end of assembly 44 to remove assembly 44 so that the core can be collapsed.
FIG. 10 shows an isometric view of the alternative embodiment. An isometric view of the preferred embodiment (not shown) would essentially the same, except three sections would be used to provide the core. As shown in this embodiment, each arcuate section has substantially the same arc radius, length and arc length.
The illustrated embodiments of the invention are intended to be illustrative only, recognizing that persons having ordinary skill in the art may construct different forms of the invention that fully fall within the scope of the subject matter disclosed herein. Other features and advantages of the invention will be apparent from the descriptions hereof.