Rackable plastic pallet

• US 5,255,613 A
• Filed: 03/12/1992
• Issued: 10/26/1993
• Est. Priority Date: 02/26/1990
• Status: Expired due to Term

• Current Assignee: Lyle H. Shuert
• Original Assignee: Lyle H. Shuert
• Inventors: Shuert, Lyle H.
• Primary Examiner(s): Dorner, Kenneth J.
• Assistant Examiner(s): Anderson, Gerald A.
• Application Number:
  US07/851,231
• Time in Patent Office: 593 Days
• Field of Search: 108/51.1, 108/52.1, 108/57.1, 108/901
• US Class Current: 108/52.1
• CPC Class Codes: B65D 19/0022 forming a continuous plane contact surface
• CPC Class Codes: B65D 19/0026 and each contact surface having a stringer-like shape
• CPC Class Codes: B65D 2519/00034 Plastic
• CPC Class Codes: B65D 2519/00069 Plastic
• CPC Class Codes: B65D 2519/00273 made of more than one piece
• CPC Class Codes: B65D 2519/00293 made of more than one piece
• CPC Class Codes: B65D 2519/00323 made of more than one piece
• CPC Class Codes: B65D 2519/00333 contact surface having a stringer-like shape
• CPC Class Codes: B65D 2519/00432 Non-integral, e.g. inserts B65D2519/00462 takes precedence
• CPC Class Codes: B65D 2519/00442 on the base surface
• CPC Class Codes: B65D 2519/00557 without separate auxiliary elements
• CPC Class Codes: B65D 2519/00562 chemical connection, e.g. glued, welded, sealed
• CPC Class Codes: B65D 2519/00572 with separate auxiliary element, e.g. screws, nails, bayonets
• CPC Class Codes: Y10S 108/901 Synthetic plastic industrial platform, e.g. pallet

Abstract

A plastic pallet in which a base structure is positioned beneath the plastic main body of the pallet to discourage warpage and failure of the pallet especially in racked, loaded storage situations. The plastic structure of the pallet includes a planar platform section defining an upwardly facing load receiving surface and a plurality of legs extending downwardly from the platform section to define tunnels therebetween for receipt of the forks of a forklift truck. The base structure includes a lower plastic sheet, an upper plastic sheet, and a plurality of tubular metallic beams positioned in hollows defined between the upper and lower plastic sheets. The hollows in which the beams are received between the sheets are defined within ribs formed on the upper face of a lower planar portion of the base structure and the ribs are respectively secured to respective rows of legs of the main body structure by locally heating the upper faces of the ribs and locally heating the bottoms of the legs of the main body structure to a fusible condition and thereafter pressing the main body structure and the base structure together to fuse the structures together at the interface between the ribs of the base structure and the bottoms of the legs of the main body structure.

Claims

1. A pallet comprising:

a plastic upper structure including an upwardly facing load receiving surface, defined by a first upper plastic sheet including a plurality of downwardly extending hollow portions opening in said load receiving surface, and downwardly facing attachment surface means defined by a second lower plastic sheet including a plurality of downwardly extending upwardly opening hollow portions nestingly receiving said downwardly extending hollow portions of said first sheet with the lower portions of the hollow portions of said first sheet fused to the lower portions of the hollow portions of said second sheet; and

a base structure positioned beneath said upper structure and including a base plastic structure having a configuration generally corresponding to the configuration of said upper structure and a plurality of beam members incorporated in said base plastic structure and extending parallel to said load receiving surface, said base plastic structure including a third upper plastic sheet having an upper surface defining an upwardly facing detachment surface means fused to said attachment surface means of said upper structure and a fourth lower plastic sheet having a lower surface defining a flat lower surface to support the pallet on a support surface, selectively fused to the third upper sheet, and selectively spaced from the third upper sheet to accommodate said beam members.

2. A pallet structure according to claim 1 wherein:

said main body plastic structure includes a plurality of legs extending downwardly from said platform section; and

said attachment surface means are defined at the bottom of said legs.

3. A pallet according to claim 2 wherein:

said base structure includes a plurality of raised portions extending from a location proximate one side edge of said base structure to a location proximate another side edge of said base structure; and

a beam member is coextensive with each raised portion.

4. A pallet according to claim 3 wherein:

said raised portions are hollow and are formed of plastic; and

said beams are metallic and one beam member is received in the hollow of each raised portion.

5. A pallet according to claim 1 wherein:

each beam member comprises a metallic tubular beam.

6. A pallet according to claim 1 wherein:

said base structure includes a generally planar lower portion and said beam members are positioned on said planar lower portion.

7. A pallet according to claim 6 wherein:

said base structure further includes a plurality of hollow rib portions upstanding from said lower planar portion and defining hollows; and

said beam members are respectively positioned in the hollows of said rib portions.

8. A pallet comprising:

a main body plastic structure defining a planar platform section defining an upwardly facing load receiving surface defined by a first upper plastic sheet and downwardly facing attachment surface means defined by a second lower plastic sheet; and

a base structure positioned beneath said platform section, secured to said attachment surface means, and including a plurality of metallic tubular beam members extending parallel to said load receiving surface and a base plastic structure having a configuration generally corresponding to the configuration of said main body plastic structure and including a plastic housing encapsulating each beam member;

each plastic housing being constituted by a first plastic sheet overlying the beam member fused to a second plastic sheet underlying the beam member.

9. A pallet comprising:

a main body plastic structure defining a planar platform section defining an upwardly facing load receiving surface defined by a first upper plastic sheet and a downwardly facing attachment surface defined by a second lower plastic sheet; and

a twin sheet base structure positioned beneath said platform section, secured to said attachment surface, and including a plurality of metallic tubular beam members extending parallel to said load receiving surface and a base plastic structure having a configuration generally corresponding to the configuration of said main body plastic structure and including upper and lower sheets selectively fused together to define a plastic housing encapsulating each beam member.

10. A pallet according to claim 9 wherein:

said base structure is secured to said plastic structure by fusing upper surfaces of said plastic housings to lower surfaces of said main body plastic structure.

11. A pallet according to claim 10 wherein said plastic structure includes a plurality of legs extending downwardly from said platform section, said attachment surface is defined by the lower faces of said legs, and said base structure is fused to the lower faces of said legs.

12. A pallet comprising:

a plastic upper structure including an upwardly facing load receiving surface, defined by a first upper plastic sheet including a plurality of downwardly extending hollow portions opening in said load receiving surface, and downwardly facing attachment surface means spaced below said load receiving surface and defined by a second lower plastic sheet including a plurality of downwardly extending upwardly opening hollow portions positioned in nesting relation with respect to said downwardly extending hollow portions of said first sheet with the lower portions of the hollow portions of said first sheet fused to the lower portions of the hollow portions of said second sheet; and

a plastic base structure including a third upper plastic sheet having an upper surface defining upwardly facing attachment surface means fused to the downwardly facing attachment surface means of said upper structure, and a fourth lower sheet positioned beneath said third sheet, having a lower surface defining a flat lower surface to support the pallet on a support surface, selectively fused to said third sheet, and selectively spaced from said third sheet to define spaces therebetween

said fused upper and base structures coacting to define tunnels therebetween for the entry of material handling equipment;

said base structure including aperture means extending therethrough to allow elements of material handling equipment positioned in said tunnels to access the support surface to facilitate the lifting of the pallet.

13. A pallet according to claim 12 wherein:

said downwardly facing attachment surface means are defined by the bottoms of said legs of said second sheet.

14. A pallet comprising:

a twin sheet plastic upper structure defining an upwardly facing load receiving surface, defined by a first upper plastic sheet including a plurality of downwardly extending hollow portions opening in said load receiving surface, and downwardly facing attachment surface means spaced below said load receiving surface defined by a second lower plastic sheet including a plurality of downwardly extending upwardly opening hollow portions nestingly receiving said downwardly extending hollow portion of said first sheet with the lower portions of the hollow portions of said first sheet fused to the lower portions of the hollow portions of said second sheet; and

a plastic base structure including a third upper plastic sheet having an upper surface defining upwardly facing attachment surface means fused to the downwardly facing attachment surface means of said upper structure, and a forth lower sheet positioned beneath said third sheet, having a lower surface defining a flat lower surface to support the pallet on a support surface, selectively fused to said third sheet, and selectively spaced from said third sheet to define spaces therebetween;

said fused upper and base plastic structures coacting to define tunnels therebetween for the entry of material handling equipment.

15. A pallet comprising:

a plastic structure including a planar platform section defining an upwardly facing load receiving surface and a plurality of legs extending downwardly from said platform section to define tunnels therebetween for receipt of the forks of a forklift truck; and

a base structure extending beneath and secured to said plastic upper structure and including a plurality of beam structures;

said beam structures being arranged in a parallel fashion beneath said plastic upper structure;

said legs being arranged in parallel rows beneath said platform section;

each beam structure being arranged beneath a row of legs;

said base structure including a planar lower portion and a plurality of parallel hollow rib portions upstanding from said lower portion and defining hollows;

each beam structure comprising a beam member received in the hollow of a respective rib portion.

16. A pallet according to claim 15 wherein:

each beam member comprises a metallic tubular beam.

17. A pallet according to claim 16 wherein:

said base structure includes a first upper plastic sheet and a second lower plastic sheet;

said upper and lower sheets are fused together to form said planar lower portion;

said rib portions are formed as raised portions of said upper sheet; and

each beam is received in the hollow of a respective rib portion with a section of said upper sheet overlying the beam and a section of the lower sheet underlying the beam.

18. A pallet comprising:

a plastic upper structure defining a planar platform section defining an upwardly facing load receiving surface and a plurality of legs arrayed in rows extending downwardly from said platform section with the bottoms of said rows defining downwardly facing attachment surface means;

a plastic base structure positioned beneath said upper structure and including upwardly facing attachment surface means confronting said downwardly facing attachment surface means and a flat lower surface spaced below said upwardly facing attachment surface means and adapted to support the pallet on a support surface, said base structure defining hollows and being fused to said plastic upper structure at the confronting interface of said attachment surface means to form a unitary plastic pallet with the fused structures coacting to define tunnels therebetween for the entry of material handling equipment;

beam members positioned in said hollows in parallel relation with each beam member positioned generally beneath a respective row of legs; and

aperture means comprising openings extending through said base structure between adjacent beam members to allow elements of material handling equipment positioned in said tunnels to access the support surface to facilitate the lifting of the pallet.