High strength, lightweight blow-molded plastic structures

• US 20030217676A1
• Filed: 04/08/2003
• Published: 11/27/2003
• Est. Priority Date: 04/09/2002
• Status: Active Grant

• Current Assignee: Lifetime Products (Lifetime)
• Original Assignee: Lifetime Products (Lifetime)
• Inventors: Strong, L. Curtis, Mower, Barry D.
• Granted Patent: US 7,069,865 B2
• Time in Patent Office: Days
• US Class Current: 108/127
• CPC Class Codes: A47B 13/003 Connecting table tops to underframes connecting furniture tubing to non-tubular parts F16B12/42
• CPC Class Codes: A47B 13/08 Table tops; Rims therefor not restricted to table tops A47B95/04
• CPC Class Codes: A47B 3/087 with struts supporting the legs
• CPC Class Codes: A47B 3/091 with struts supporting the legs in combination with foldable top leaves A47B3/087
• CPC Class Codes: A47B 3/0912 the strut being of two parts foldable relative to one another
• CPC Class Codes: A63B 63/083 for basketball
• CPC Class Codes: B29C 49/0031 Making articles having hollow walls
• CPC Class Codes: B29C 49/04 Extrusion blow-moulding
• CPC Class Codes: B29C 49/4802 with means for locally compressing part(s) of the parison in the main blowing cavity
• CPC Class Codes: B29K 2995/0077 Yield strength; Tensile strength
• CPC Class Codes: B29K 2995/0082 Flexural strength; Flexion stiffness
• CPC Class Codes: B29K 2995/0089 Impact strength or toughness
• CPC Class Codes: B29L 2031/448 Tables
• CPC Class Codes: B29L 2031/52 Sports equipment ; Games; Articles for amusement; Toys B29L2031/54 takes precedence
• CPC Class Codes: F16B 12/24 using separate pins, dowels, or the like
• CPC Class Codes: Y10T 428/1397 Single layer [continuous layer]
• CPC Class Codes: Y10T 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]

Abstract

Blow molded plastic structures are provided for use in various structures such as, but not limited to, tables, chairs, walls, backboards, storage bins, sports equipment and the like. The blow molded plastic structure has a first surface and a second surface extending between a first end and a second end and forming a chamber there between. A plurality of depressions is formed on the second surface and extends into the chamber. The depressions are usually unitary structures formed by a depression wall. Generally, the steeper the depression wall, the more strength is provided to the structure. In addition, where the plurality of depressions has a low profile and a greater density, increased strength is provided to the structure. The depressions may or may not be joined to the first surface.

Claims

1. A structure constructed from blow-molded plastic, the structure comprising:

a first surface;

a second surface that is disposed generally parallel to and spaced apart from the first surface, the first surface being separated from the second surface by a distance, the first and second surfaces enclosing at least a portion of a generally hollow interior of the blow-molded structure;

a plurality of depressions formed in the second surface and extending towards the first surface, each of the plurality of depressions including a sidewall and an end, each of the plurality of depressions having a height measured from the second surface to the end of the depression, the plurality of depressions being arranged into a pattern in which a distance separating adjacent depressions is approximately equal to or less than three times the distance separating the first surface and the second surface.

2. The blow-molded plastic structure as in claim 1, wherein the end of each of the plurality of depressions engages the first surface.

3. The blow-molded plastic structure as in claim 1, wherein the sidewall of each of the plurality of depressions is at an angle between about 60°

and about 85°

relative to the second surface.

4. The blow-molded plastic structure as in claim 1, wherein the plurality of depressions cover substantially the entire second surface.

5. The blow-molded plastic structure as in claim 1, wherein the plurality of depressions allow a thickness of the first surface and the second surface to be decreased.

6. The blow-molded plastic structure as in claim 1, wherein the plurality of depressions have a generally uniform and consistent spacing across substantially all the second surface of the blow-molded structure.

7. The blow-molded plastic structure as in claim 1, wherein the plurality of depressions have a generally uniform and consistent spacing across substantially all the second surface of the blow-molded structure so that the blow-molded structure has generally uniform strength and structural integrity.

8. The blow-molded structure as in claim 1, wherein the plurality of depressions are arranged into a pattern in which a distance separating adjacent depressions is generally equal to or less than two times the distance separating the first surface and the second surface.

9. The blow-molded structure as in claim 1, wherein the plurality of depressions are arranged into a pattern in which a distance separating adjacent depressions is generally equal to or less than the distance separating the first surface and the second surface.

10. The blow-molded plastic structure as in claim 1, wherein the end of each of the plurality of depressions is spaced apart from the first surface.

11. The blow-molded plastic structure as in claim 1, wherein the plurality of depressions are integrally formed in the blow-molded plastic structure as part of a unitary, one-piece structure.

12. A table comprising:

a table top constructed from blow-molded plastic and including a generally hollow interior, the table top including an upper surface, a lower surface and a thickness measured from the upper surface to the lower surface;

a plurality of depressions integrally formed in the lower surface of the table top as part of a unitary, one-piece structure, the plurality of depressions being sized and configured to increase the strength of the table top, each adjacent depression of the plurality of depressions being separated by a distance that is generally equal to or less than three times the thickness of the table top; and

a support structure that is connected to the table top to support the table top above a surface.

13. The table as in claim 12, wherein the end of each of the plurality of depressions engages the upper surface of the table top.

14. The table as in claim 12, wherein the end of each of the plurality of depressions is spaced apart from the upper surface of the table top.

15. The table as in claim 12, wherein each of the plurality of depressions has a sidewall that is at an angle of at least about 75°

with respect to the lower surface.

16. The table as in claim 12, wherein the plurality of depressions cover substantially the entire lower surface of the table top.

17. The table as in claim 12, wherein the plurality of depressions have a generally uniform and consistent spacing across substantially all the lower surface of the table top.

18. The table as in claim 12, wherein the distance separating each adjacent depression of the plurality of depressions being generally equal to or less than two times the thickness of the table top.

19. The table as in claim 12, wherein the distance separating each adjacent depression of the plurality of depressions is generally equal to or less than the thickness of the table top.

20. A basketball backboard constructed from blow-molded plastic, the basketball backboard comprising:

a first surface;

a second surface spaced apart from the first surface, at least a portion of the first surface and the second surface enclosing a generally hollow interior portion of the basketball backboard; and

a plurality of depressions integrally formed in the second surface as part of a unitary, one-piece structure, the depressions including a height and being located in a pattern that covers substantially all of the second surface, each of the adjacent depressions in the pattern of depressions being separated by a distance that is generally less than or equal to three times a distance separating the first surface from the second surface.

21. The basketball backboard as in claim 20, wherein an end of each of the plurality of depressions engages the first surface of the basketball backboard.

22. The basketball backboard as in claim 20, wherein an end of each of the plurality of depressions is spaced apart from the first surface of the basketball backboard.

23. The basketball backboard as in claim 20, wherein each of the plurality of depressions has a sidewall that is at an angle of at least about 75°

with respect to the second surface.

24. The basketball backboard as in claim 20, wherein the plurality of depressions have a generally uniform and consistent spacing across substantially all the second surface of the basketball backboard.

25. The basketball backboard as in claim 20, wherein the distance separating each adjacent depression of the plurality of depressions is generally equal to or less than two times the distance separating the first surface and the second surface.

26. The basketball backboard as in claim 20, wherein the distance separating each adjacent depression of the plurality of depressions is generally equal to or less than the distance separating the first surface and the second surface.

27. A table comprising:

a table top constructed from blow-molded plastic and including a generally hollow interior, the table top including an upper surface, a lower surface and a thickness measured from the upper surface to the lower surface;

a plurality of depressions integrally formed in the lower surface of the table top as part of a unitary, one-piece structure, each of the plurality of depressions having a height generally measured from the lower surface to an end of the depression, each adjacent depression of the plurality of depressions being separated by a distance that is generally equal to or less than three times the height of the depression; and

a support structure that is connected to the table top to support the table top above a surface.