Water resistant shipping containers are desirable for shipping many types of products, such as fresh produce and frozen goods. Currently available containers are typically manufactured from container blanks that are encapsulated within a water resistant film. Such blanks are assembled by applying a film to at least one side and, in some circumstances, both sides of the blank and trimming to size. The covered blank is then heated above the softening point of the film. The film becomes bonded to the surfaces of the blanks, and sags around the edges and into any openings so that the film on the two sides of the blank come into contact and are sealed together.
Thereafter, the edges and any slits and cutouts are trimmed, such as by a die cutter, while preserving the seals along the edges. One such method of manufacturing an encapsulated blank is disclosed in U.S. Pat. No. 6,338,234, entitled Method of Encapsulating Shipping Container Blanks in Plastic Film, assigned to Weyerhaeuser Company of Federal Way, Wash., the disclosure of which is hereby expressly incorporated by reference.
While current manufacturing methods are effective at encapsulating blanks, they are not without their problems. As a nonlimiting example, during the trimming process, the cutter may not trim away all unwanted material from cutting areas, such as handholds, tabs, etc. Also, if the encapsulation assembly is operating at a rate faster than its design speed, the cutter may not singulate all blanks. Thus, there exists a need for a trim device for a lamination apparatus.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
A trim device for a lamination apparatus is provided. The lamination apparatus provides a cellulous based panel with at least one polymeric layer. The trim device includes a housing and a material removal apparatus at least partially disposed within the housing. The trim device also includes a pressure source in communication with the material removal apparatus. The pressure source is adapted to provide a pressure differential to the cellulous based panel having a waste section. The pressure differential positions the waste section into communication with the material removal apparatus so that the waste section is removed from the cellulous based panel during operation of the trim device.
A method of removing a waste section from a cellulous based panel is also provided. The method includes providing a cellulous based panel having at least one layer of lamination and a waste section, and displacing the waste section into a cutting position. The method further includes removing the waste section by impacting the waste section with a trim device after the waste section has been disposed into the cutting position.
The foregoing aspects and many of the attendant advantages of this invention will become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
A trim device 20 constructed in accordance with one embodiment of the present disclosure maybe best understood by referring to
The encapsulation apparatus 26 and cutting apparatus 28 are also well-known to provide at least one layer of lamination to the cellulose base blank. Such methods of laminating are disclosed in U.S. Pat. No. 6,338,234, entitled Method of Encapsulating Shipping Container Blanks in Plastic Film. The lamination apparatus 20 applies at least one water resistant layer to a container blank 30, suitably formed from well-known cellulose materials, such as wood pulp, straw, cotton, bagasse and the like. The water resistant layer is formed from well-known materials, such as a polymeric material, wax, and the like.
The cutting apparatus 28 is adapted to cut predetermined shapes, such as hand-holds, ventilation ports, and other defined apertures. Although cutting apparatuses 28 are effective at cutting such predetermined shapes from blanks 30, they sometimes fail to completely remove the material defining the aperture, thereby defining a waste section 32. Typically, the waste section 32 is attached to the blank 30 by a small portion of the waste section 32 still being attached to a portion of the blanks 30. To remove the waste section 32 from the blank 30, the blank 30 is fed to the trim device 20 on a well-known conveyor 34.
As may be best understood by referring to
The trim device 20 may also include a slide gate damper assembly 80 connected to the housing 40 adjacent the cutting port 48, as shown best in
As may be best seen by referring to
The cutting blades 52 and spacers 54 are rotatably disposed on the axle 50 and seated thereon by a well-known bearing 56. A drive motor (not shown) is suitably attached to one end of the axle 50 for driving the plurality of cutting blades 52. The material removal apparatus 42 is sealed within the housing 40 by an end cap 58. Although it is preferred that the material removal apparatus 42 be rotatably disposed within the housing 40, other configurations are within the scope of the present disclosure. As a non-limiting example, the cutting blades 52 may be disposed within the housing 40 and configured for translational movement laterally along the axle 50 in a side-to-side type of motion. Accordingly, such configurations are also within the scope of the appended claims.
Operation of the trim device 20 may be best understood by referring to
In the cutting position, at least one cutting tip 60 of the cutting blade 52 engages the waste section 32, causing it to be separated from the blank 30. After the waste section 32 is separated from the blank 30, the pressure differential sucks the waste section 32 out of the housing 40 through the pressure source port 46 and into a waste collector 60. To assist in retaining the blank 30 on the conveyer 34 as it passes the trim device 20, a hold down roller 62 may be provided.
Although a pressure differential is preferred for displacing the waste section 32 into the cutting position, other methods are within the scope of the present disclosure. As an example, the material used to construct either the blank 30 or the lamination may be charged such that the waste section 32 may be displace it into the cutting position. As yet another example, the trim device 20 may include a scoop to lift the waste section 32 into the cutting position as the blank 30 passes the trim device 20.
In operation, the axle 50 may be rotated at a rate such that the cutting tip 60 has a tip speed of approximately 100 feet per second. The housing 40 is suitably under a negative pressure differential between 5 and 20 inches of water to induce an air flow into the housing 40. As noted above, this pressure differential causes the waste section 32 to lift upward from the surface of the blank 30 were it impacts with the cutting tip 60 and the waste section 32 raps around the cutting tip 60. This impact results in a momentum that causes the waste section 32 to be separated from the blank 30.
A trim device 110 constructed in accordance with an alternate embodiment of the present invention may be best understood by referring to
While illustrative embodiments have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention. As an example, the conveyor 34 may include an embedded vacuum source to assist in retaining the blank 30 as it is transported to the trim device 20. As a result, such embodiments are also contemplated with the scope of the appended claims.