Corrugated drainage pipe with plateaus defining recesses

Claim 2

A resilient plastic drainage pipe having spaced apart successively arranged ribs with interconnecting valley portions therebetween defining annular corrugations along the periphery of the pipe, the majority of said ribs being uninterrupted and arranged in spaced groups with an interrupted rib between adjacent groups, and each interrupted rib having at least one elongate recessed wall portion defining an interruption therein positioned at a level intermediate that of the peripheries of said ribs and said valley portions.

Claim 3

A resilient plastic drainage pipe according to claim 1, wherein a drainage hole is provided in each recessed wall portion of each interrupted rib with the diameter of the hole being greater than the width of the ribs.

Claim 4

A resilient plastic drainage pipe according to claim 1, wherein said recessed wall portion has a width at least as wide as the medial portion of the interrupted rib.

Claim 5

A resilient plastic drainage pipe according to claim 1, wherein side walls extend radially inwardly from opposite sides of said recessed wall portion and inter-connect the same with said valley portions.

Claim 6

A resilient plastic drainage pipe according to claim 1, wherein said recessed wall portion in each interrupted rib extends outwardly into and interrupts the valley portions adjacent thereto.

Claim 7

A resilient plastic drainage pipe having spaced apart successively arranged ribs with interconnecting valley portions therebetween defining annular corrugations along the periphery of the pipe, the majority of said ribs being uninterrupted and arranged in spaced groups with an interrupted rib between adjacent groups, each interrupted rib comprising a set of three circularly arranged spaced apart arcuate rib segments correspondingly arranged throughout the pipe, one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, and recessed wall portions extending between and interconnecting adjacent arcuate rib segments, said recessed wall portions being of a width at least as wide as the medial portion of said arcuate rib segments and positioned at a level intermediate that of the peripheries of said ribs and said valley portions.

Claim 8

A resilient plastic drainage pipe having spaced apart successively arranged ribs with interconnecting valley portions therebetween defining annular corrugations along the periphery of the pipe, the majority of said ribs being uninterrupted and arranged in spaced groups with an interrupted rib between adjacent groups, each interrupted rib comprising a set of three circularly arranged spaced apart arcuate rib segments correspondingly arranged throughout the pipe, one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, and recessed wall portions extending between and interconnecting adjacent arcuate rib segments, said recessed wall portions being of a width at least as wide as the medial portion of said arcuate rib segments and positioned at a level intermediate that of the peripheries of said ribs and said valley portions.

Claim 9

A resilient plastic drainage pipe according to claim 6, wherein a drainage hole is provided in each of said recessed wall portions of each interrupted rib with the diameter of the hole being greater than the width of the rib.

Claim 10

A resilient plastic drainage pipe according to claim 6, wherein said recessed wall portions are arcuate and of a radius generated about the axis of the pipe.

Claim 11

A resilient plastic drainage pipe according to claim 6, wherein said recessed wall portions are arcuate and of a radius greater than the radius of the pipe so that central areas of the recessed wall portions are positioned closer to the axis of the pipe than other areas thereof.

Claim 12

A resilient plastic drainage pipe according to claim 6, wherein side walls extend radially inwardly from opposite sides of said recessed wall portions and interconnect the same with said valley portions.

Claim 13

A resilient plastic drainage pipe according to claim 6, wherein said recessed wall portions in each interrupted rib extend outwardly into and interrupt the valley portions adjacent thereto.

Claim 14

A resilient plastic drainage pipe having spaced apart successively arranged ribs with interconnecting valley portions therebetween defining annular corrugations along the periphery of the pipe, the majority of said ribs being uninterrupted and arranged in spaced groups with an interrupted rib between adjacent groups, each interrupted rib comprising a set of three circularly arranged space apart arcuate rib segments correspondingly arranged throughout the pipe, one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, elongate recessed wall portions extending between and interconnecting adjacent arcuate rib segments, said recessed wall portions being Positioned at a level intermediate that of the peripheries of said ribs and said valley portions, a drainage hole provided in each of said recessed wall portions, and end wall portions extending radially outwardly from opposite ends of each recessed wall portion to the periphery of the interrupted rib to define the arcuate extent of the interruptions.

Claim 15

A resilient plastic drainage pipe having spaced apart successively arranged ribs with interconnecting valley portions therebetween defining annular corrugations along the periphery of the pipe, the majority of said ribs being uninterrupted and arranged in spaced groups with an interrupted rib between adjacent groups, each interrupted rib comprising a set of three circularly arranged space apart arcuate rib segments correspondingly arranged throughout the pipe, one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, elongate recessed wall portions extending between and interconnecting adjacent arcuate rib segments, said recessed wall portions being Positioned at a level intermediate that of the peripheries of said ribs and said valley portions, a drainage hole provided in each of said recessed wall portions, and end wall portions extending radially outwardly from opposite ends of each recessed wall portion to the periphery of the interrupted rib to define the arcuate extent of the interruptions.

Claim 16

A resilient plastic drainage pipe having spaced apart successively arranged ribs with interconnecting valley portions therebetween defining annular corrugations along the periphery of the pipe, the majority of said ribs being uninterrupted and arranged in spaced groups with an interrupted rib between adjacent groups, each interrupted rib having at least one elongate recessed wall portion defining an interruption therein and positioned at a level intermediate that of the peripheries of said ribs and said valley portions, side walls extending radially inwardly from opposite sides of said recessed wall portion and interconnecting the same with said valley portions, and a drainage hole provided in each recessed wall portion.

Claim 17

A resilient plastic drainage pipe having spaced apart successively arranged ribs with interconnecting valley portions therebetween defining annular corrugations along the periphery of the pipe, the majority of said ribs being uninterrupted and arranged in spaced groups with an interrupted rib between adjacent groups, each interrupted rib having at least one elongate recessed wall portion defining an interruption therein and positioned at a level intermediate that of the peripheries of said ribs and said valley portions, side walls extending radially inwardly from opposite sides of said recessed wall portion and interconnecting the same with said valley portions, and a drainage hole provided in each recessed wall portion.

Claim 18

A resilient plastic drainage pipe according to claim 13, wherein end walls extend radially outwardly from opposite ends of said recessed wall portion to the periphery of the interrupted rib and define the arcuate extent of the interruption.