Undulating molded plastic vibratory screen

1. An undulating molded plastic vibratory screen comprising:

a base,

a plurality of spaced substantially parallel elongated undulations on said base, and

screen configurations on said undulations said base includes a plurality of first ribs extending longitudinally internally of at least certain of said undulations, and a plurality of second ribs extending crosswise to said plurality of first ribs and molded integrally therewith wherein said plurality of first ribs are located in first undulations which are spaced from each other by at least one second undulation which does not have a first rib therein.

2. An undulating molded plastic vibratory screen comprising:

a base,

a plurality of spaced substantially parallel elongated undulations on said base, and

screen configurations on said undulations said base includes a plurality of first ribs extending longitudinally internally of at least certain of said undulations, and a plurality of second ribs extending crosswise to said plurality of first ribs and molded integrally therewith wherein said screen configurations comprise sides of said undulations and are molded integrally with said second ribs wherein said undulations have inner surfaces and outer surfaces, third ribs molded integrally with said second ribs and extending longitudinally of said undulations, and said third ribs having first edges molded integrally with said inner surfaces and second edges which are free of said inner surfaces.

3. The undulating molded plastic vibratory screen as set forth in claim 2 wherein said third ribs are also molded to said second ribs at the junctions of said inner surfaces with said second ribs.

4. An undulating molded plastic vibratory screen comprising:

a base,

a plurality of spaced substantially parallel elongated undulations on said base, and

screen configurations on said undulations said base includes a plurality of first ribs extending longitudinally internally of at least certain of said undulations, and a plurality of second ribs extending crosswise to said plurality of first ribs and molded integrally therewith wherein said screen configurations comprise sides of said undulations and are molded integrally with said second ribs including a plurality of third ribs in said first undulations, and a plurality of fourth ribs in said second undulations.

5. The undulating molded plastic vibratory screen as set forth in claim 4 wherein said third ribs are molded integrally with said second ribs and extend longitudinally of said first undulations, and wherein said first undulations have inner and outer surfaces, and said third ribs have first edges molded integrally with said inner surfaces of said first undulations and second edges which are free of said inner surfaces of said first undulations.

6. The undulating molded plastic vibratory screen as set forth in claim 5 wherein said third ribs are also molded to said second ribs at the junctions of said inner surfaces with said second ribs.

7. The undulating molded plastic vibratory screen as set forth in claim 5 wherein said first undulations have lower edges and higher edges, and wherein said first undulations have opposite sides, and wherein said third ribs are molded to said inner surfaces of each of said opposite sides intermediate said higher and lower edges of said first undulations.

8. The undulating molded plastic vibratory screen as set forth in claim 4 wherein said fourth ribs are molded integrally with said second ribs and extend longitudinally of said second undulations, and wherein said second undulations have inner and outer surfaces, and said fourth ribs have first edges molded integrally with said inner surfaces of said second undulations and second edges which are free of said inner surfaces of said second undulations.

9. The undulating molded plastic vibratory screen as set forth in claim 8 wherein said first edges of said fourth ribs are also molded to said second ribs at the junctions of said inner surfaces of said second undulations with said second ribs.

10. The undulating molded plastic vibratory screen as set forth in claim 9 wherein said second undulations have lower edges and higher edges, and wherein said second undulations have opposite sides, and wherein said fourth ribs are molded to each of said inner surfaces of said opposite sides of said second undulations proximate said higher edges, and fifth ribs are molded to each of said inner surfaces of said opposite sides of said second undulations intermediate said lower and higher edges.

11. The undulating molded plastic vibratory screen as set forth in claim 10 wherein said third ribs are molded integrally with said second ribs and extend longitudinally of said first undulations, and wherein said first undulations have inner and outer surfaces, and wherein said third ribs have first edges molded integrally with said inner surfaces of said first undulations and second edges which are free of said inner surfaces of said first undulations.

12. The undulating molded plastic vibratory screen as set forth in claim 11 wherein said third ribs are also molded to said second ribs at the junctions of said inner surfaces with said second ribs.

13. The undulating molded plastic vibratory screen as set forth in claim 12 wherein said first undulations have lower edges and higher edges, and wherein said first undulations have opposite sides, and wherein said third ribs are molded to said inner surfaces of each of said opposite sides intermediate said higher and lower edges of said first undulations.

14. An undulating molded plastic vibratory screen comprising:

a base,

a plurality of spaced substantially parallel elongated undulations on said base, and

screen configurations on said undulations said base includes a plurality of first ribs extending longitudinally internally of at least certain of said undulations, and a plurality of second ribs extending crosswise to said plurality of first ribs and molded integrally therewith wherein said first ribs have first higher edges and first lower edges, and wherein said second ribs have second higher edges and second lower edges, and wherein said first and second lower edges lie in substantially the same plane.

15. The undulating molded plastic vibratory screen as set forth in claim 14 wherein said first and second undulations have first and second peaks, respectively, and wherein said first higher edges of said first ribs terminate at said first peaks, and said second higher edges of said second ribs terminate at both said first and second peaks.

16. The undulating molded plastic vibratory screen as set forth in claim 15 wherein said first and second undulations are trapezoidal in cross section.

17. An undulating molded plastic vibratory screen comprising:

a base,

a plurality of spaced substantially parallel elongated undulations on said base, and

screen configurations on said undulations said base includes a plurality of first ribs extending longitudinally internally of at least certain of said undulations, and a plurality of second ribs extending crosswise to said plurality of first ribs and molded integrally therewith wherein said first undulations have first opposite ends, and wherein said second undulations have second opposite ends, first end caps molded integrally with said first opposite ends, second end caps molded integrally with said second opposite ends, and wherein said first ribs have third opposite ends which are molded integrally with said first end caps.

18. An undulating molded plastic vibratory screen comprising:

a base,

a plurality of spaced substantially parallel elongated undulations on said base, and

screen configurations on said undulations said base includes a plurality of first ribs extending longitudinally internally of at least certain of said undulations, and a plurality of second ribs extending crosswise to said plurality of first ribs and molded integrally therewith wherein said screen configurations comprise sides of said undulations and are molded integrally with said second ribs, and wherein said screen configurations also comprise the tops of said second undulations.

19. An undulating molded plastic vibratory screen comprising a base, a plurality of spaced substantially parallel elongated undulations on said base, and screen configurations on said undulations said base includes a plurality of first ribs extending longitudinally internally of at least certain of said undulations, and a plurality of second ribs extending crosswise to said plurality of first ribs and molded integrally therewith wherein said second undulations include inner and outer sides, and wherein said second undulations have lower edges and higher edges, third ribs secured to said inner sides intermediate said lower and higher edges, and fourth ribs secured relative to said inner sides proximate said higher edges, and said third and fourth ribs extending longitudinally of said second undulations.

20. The undulating molded plastic vibratory screen as set forth in claim 19 wherein said third and fourth ribs extend between and are molded integrally with said second ribs.

21. The undulating molded plastic vibratory screen as set forth in claim 19 wherein said first undulations include second inner and outer sides, and wherein said first undulations have second lower and higher edges, and fifth ribs secured to said second inner sides intermediate said second lower and higher edges.

22. The undulating molded plastic vibratory screen as set forth in claim 21 wherein said fifth ribs extend between and are molded integrally with said second ribs.

23. The undulating molded plastic vibratory screen as set forth in claim 22 wherein said third and fourth ribs extend between and are molded integrally with said second ribs.

24. The undulating molded plastic vibratory screen as set forth in claim 23 wherein said screen configurations also comprise the tops of said second undulations.