Large diameter corrugated plastic pipe

Claim 2

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe (a) a pipe having a generally cylindrical corrugated wall structure with spaced apart successive annular ribs with annular valley defining portions therebetween; (b) said wall structure being formed of either high density polyethylene, PVC or polypropylene and being sufficiently thick so as to be relatively inflexible, rigid but elastic throughout and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising (1) a generally cylindrical relatively inflexible, rigid but elastic through-out sleeve element integrally formed with said wall structure and of the same material and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar having a smaller and a larger end and supporting said sleeve element upon the end of said wall structure of the remainder of the pipe and extending therebetween and being integrally formed therewith and having the smaller end thereof connected to said wall structure in supported relation and the larger end thereof connected to said sleeve element in supporting relation; (3) a plurality of circumferentially spaced latching members located intermediate the ends of said sleeve element and integrally formed therewith of the same material and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a lever member supported at one of its ends at its fulcrum by said sleeve element and formed integrally therewith of the same material and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its other end and along each of its sides to permit same to pivot at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the free end of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (7) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to a point adjacent its said latching surface; and (8) each of said latching elements extending radially inwardly from its supporting lever member a distance at least equal to 25% of the depth of the valley-defining portions of said pipe.

Claim 3

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley defining portions therebetween; (b) said wall structure being rigid but elastic throughout and formed of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a generally cylindrical, inflexible, rigid but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar supporting said sleeve element upon the end of said wall structure of the remainder of the pipe and extending therebetween and being integrally formed therewith and having a smaller end thereof connected to said wall structure in supported relation and a larger end thereof connected to said sleeve element in supporting relation; and (3) a plurality of spaced latching members located intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (7) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; and (8) said corrugated wall structure having a thickness of at least 0.050 inch.

Claim 4

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley defining portions therebetween; (b) said wall structure being rigid but elastic throughout and formed of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a generally cylindrical, inflexible, rigid but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar supporting said sleeve element upon the end of said wall structure of the remainder of the pipe and extending therebetween and being integrally formed therewith and having a smaller end thereof connected to said wall structure in supported relation and a larger end thereof connected to said sleeve element in supporting relation; and (3) a plurality of spaced latching members located intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (7) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; and (8) said corrugated wall structure having a thickness of at least 0.050 inch.

Claim 5

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being rigid and elastic throughout and integrally formed preferably of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a generally cylindrical, inflexible, rigid but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar supporting said sleeve element upon the end of said wall structure of the remainder of the pipe and extending therebetween and being integrally formed therewith and having a smaller end thereof connected to said wall structure in supported relation and a larger end thereof connected to said sleeve element in supporting relation; (3) a plurality of spaced latching members located intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (7) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; and (8) said annular ribs each having a crown with an axial dimension of at least 11/16 inches.

Claim 6

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being rigid and elastic throughout and integrally formed preferably of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a generally cylindrical, inflexible, rigid but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar supporting said sleeve element upon the end of said wall structure of the remainder of the pipe and extending therebetween and being integrally formed therewith and having a smaller end thereof connected to said wall structure in supported relation and a larger end thereof connected to said sleeve element in supporting relation; (3) a plurality of spaced latching members located intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (7) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; and (8) said annular ribs each having a crown with an axial dimension of at least 11/16 inches.

Claim 7

The structure defined in claim 1 wherein said corrugated wall structure has a thickness of at least 0.050 inch.

Claim 8

The structure defined in claim 1 wherein said corrugated wall structure has a thickness of at least 0.050 inch and the high density polyethylene from which it is made has a specific gravity of approximately 0.955.

Claim 9

The structure defined in claim 1 wherein said annular ribs have an axial dimension of at least 11/16 inch.

Claim 10

The structure defined in claim 1 wherein said corrugated wall structure has a thickness of at least 0.050 inch and said annular ribs have an axial dimension of at least 11/16 inch.

Claim 11

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being rigid but elastic and integrally formed of high density polyethylene extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a generally cylindrical rigid but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a substantially frusto-conically shaped support collar supporting said sleeve element upon the end of said wall structure of the remainder of the pipe and extending therebetween and being integrally formed therewith and having the smaller end thereof connected to said wall structure in supported relation and the larger end thereof connected to said sleeve element in supporting relation; (3) a plurality of spaced latching members located intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever elements carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) each of said latching members having a latching surface and being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; and (7) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface.

Claim 12

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being rigid but elastic and integrally formed of high density polyethylene extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a generally cylindrical rigid but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a substantially frusto-conically shaped support collar supporting said sleeve element upon the end of said wall structure of the remainder of the pipe and extending therebetween and being integrally formed therewith and having the smaller end thereof connected to said wall structure in supported relation and the larger end thereof connected to said sleeve element in supporting relation; (3) a plurality of spaced latching members located intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever elements carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) each of said latching members having a latching surface and being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; and (7) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface.

Claim 13

The structure defined in claim 8, wherein said wall structure at the opposite end portion of the pipe terminates at the bottom of one of its said valley portions.

Claim 14

The structure defined in claim 8 wherein said latching members are located on said sleeve element so that the said latching surface of each is disposed so as to extend into, engage and latch a valley-defining wall portion of an opposite end portion of a similarly formed drainage pipe when the latter is inserted into said sleeve element and into abutting relation with said collar.

Claim 15

The structure defined in claim 8 wherein said latching members are located on said sleeve element so that the said latching surface of each is disposed outwardly of the bottom of the adjacent valley portion of said remainder of said pipe a distance substantially equal to 1.50 times the axial distance between two adjacent valley portions of said wall structure.

Claim 16

The structure defined in claim 8 wherein said latching members are located on said sleeve element so that the said latching surfaces of each is disposed outwardly of the bottom of the adjacent valley portion of said remainder of said pipe a distance at least equal to 1.50 times the axial distance between two adjacent valley portions of said wall structure.

Claim 17

The structure defined in claim 8 wherein said wall structure of the opposite end portion of the pipe terminates at the bottom of one of the said valley portions of said wall structure; and (d) a second and similarly formed pipe having its said opposite end portion inserted into said sleeve element with the end thereof abutting said collar.

Claim 18

The structure defined in claim 8 wherein the base of said latching members are located on said sleeve elements so that the latching surface of each is located a distance from the pitch line of the valley adjacent said latching members substantially equal to 1.50 times the axial distance between the pitch lines of a pair of such valley portions adjacent to each other.

Claim 19

The structure defined in claim 8 wherein said collar is integrally formed with and supported by said wall structure of a valley-defining portion of the remainder of the pipe.

Claim 20

The structure defined in claim 8 wherein said collar is supported by the terminal portion of said wall structure of a valley-defining portion of the remainder of the pipe.

Claim 21

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being inflexible and being rigid but elastic throughout and formed of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a cylindrical rigid, inflexible, but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar connected to the end of said wall structure of the remainder of the pipe in supported relation and supporting said sleeve element thereupon in coaxial relation and extending therebetween and being integrally formed therewith; and (3) a plurality of spaced latching members intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a rigid but elastic lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; (7) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element.

Claim 22

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being inflexible and being rigid but elastic throughout and formed of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a cylindrical rigid, inflexible, but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar connected to the end of said wall structure of the remainder of the pipe in supported relation and supporting said sleeve element thereupon in coaxial relation and extending therebetween and being integrally formed therewith; and (3) a plurality of spaced latching members intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a rigid but elastic lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; (7) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element.

Claim 23

The structure defined in claim 17 wherein said collar extends in its entirety radially outwardly of its point of connection with its said supporting wall structure.

Claim 24

The structure defined in claim 17 wherein said latch members are located on said sleeve elements so that the latching surface of each is located a distance from the pitch line of the valley adjacent said latching members substantially 1.50 times the axial distance between the pitch lines of a pair of such valley portions adjacent to each other.

Claim 25

A pipe coupling for large-diameter corrugated plastic pipe having inherently non-releasable coupling means readily accessible from the exterior when coupled to end sections of such pipe, comprising: (a) a pipe having wall structure formed of a member of a group made up of high density polyethylene, PVC, and polypropylene and being sufficiently thick so as to be inflexible, rigid but elastic throughout; (b) said pipe having opposite end portions and an intermediate portion; (c) the wall structure of said end portions having an internal diameter only slightly larger than the external diameter of the corrugated pipe to be coupled thereby; (d) said intermediate portion of said pipe being comprised of a single inwardly extending corrugation having an internal diameter substantially less than the external diameter of the corrugated pipe to be coupled thereby; (e) a pair of frusto-conically shaped collars carried by said intermediate portion at the outer ends of said single corrugation and one each of which supports one of said end portions of said pipe; (f) the smaller end of each of said collars being directly connected to and supported by said single corrugation of said intermediate portion; (g) the larger end of each of said collars being connected directly and in supporting relation to one of said end portions; (h) a plurality of circumferentially spaced latching members located on each of said end portions outwardly of said single corrugation and integrally formed therewith and each extending inwardly from its supporting end portion around its interior in the same transverse plane relative thereto, the diametrical distance between the radially inner ends of said latching members being substantially less than the outer diameter of the corrugated pipe to be coupled thereby; (i) each of said latching members being comprised of a lever member supported at one of its ends at its fulcrum by said end portion and formed integrally therewith of the same material and extending in the plane thereof from the fulcrum toward said intermediate portion and being free at its other end and along each of its sides to permit same to pivot at its fulcrum along a circumferential line of said end portion; (j) each of said lever members carrying a latch element which depends inwardly therefrom and has a latching surface adjacent the free end of its associated lever member extending radially of said end portion and facing toward said intermediate portion; (k) said latching members being constructed, arranged and located on said end portions so that the latching surfaces thereof will extend into and engage in latching relation valley-defining portions of the corrugated pipe to be coupled thereto when the latter is thrust into one end portion of said pipe; and (1) each of said lever members also having a camming surface located outwardly of its associated latching surface and extending radially inwardly relative to said intermediate portion from a point adjacent the fulcrum of said lever member to a point adjacent its said latching surface, each of said latching members extending radially inwardly from its supporting lever member a distance in excess of 25% of the depth of the corrugation defining portions of said intermediate portion.

Claim 26

A pipe coupling for large-diameter corrugated plastic pipe having inherently non-releasable coupling means readily accessible from the exterior when coupled to end sections of such pipe, comprising: (a) a pipe having wall structure formed of a member of a group made up of high density polyethylene, PVC, and polypropylene and being sufficiently thick so as to be inflexible, rigid but elastic throughout; (b) said pipe having opposite end portions and an intermediate portion; (c) the wall structure of said end portions having an internal diameter only slightly larger than the external diameter of the corrugated pipe to be coupled thereby; (d) said intermediate portion of said pipe being comprised of a single inwardly extending corrugation having an internal diameter substantially less than the external diameter of the corrugated pipe to be coupled thereby; (e) a pair of frusto-conically shaped collars carried by said intermediate portion at the outer ends of said single corrugation and one each of which supports one of said end portions of said pipe; (f) the smaller end of each of said collars being directly connected to and supported by said single corrugation of said intermediate portion; (g) the larger end of each of said collars being connected directly and in supporting relation to one of said end portions; (h) a plurality of circumferentially spaced latching members located on each of said end portions outwardly of said single corrugation and integrally formed therewith and each extending inwardly from its supporting end portion around its interior in the same transverse plane relative thereto, the diametrical distance between the radially inner ends of said latching members being substantially less than the outer diameter of the corrugated pipe to be coupled thereby; (i) each of said latching members being comprised of a lever member supported at one of its ends at its fulcrum by said end portion and formed integrally therewith of the same material and extending in the plane thereof from the fulcrum toward said intermediate portion and being free at its other end and along each of its sides to permit same to pivot at its fulcrum along a circumferential line of said end portion; (j) each of said lever members carrying a latch element which depends inwardly therefrom and has a latching surface adjacent the free end of its associated lever member extending radially of said end portion and facing toward said intermediate portion; (k) said latching members being constructed, arranged and located on said end portions so that the latching surfaces thereof will extend into and engage in latching relation valley-defining portions of the corrugated pipe to be coupled thereto when the latter is thrust into one end portion of said pipe; and (1) each of said lever members also having a camming surface located outwardly of its associated latching surface and extending radially inwardly relative to said intermediate portion from a point adjacent the fulcrum of said lever member to a point adjacent its said latching surface, each of said latching members extending radially inwardly from its supporting lever member a distance in excess of 25% of the depth of the corrugation defining portions of said intermediate portion.

Claim 27

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being inflexible and being rigid but elastic throughout and formed of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a cylindrical rigid, inflexible, but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar connected to the end of said wall structure of the remainder of the pipe in supported relation and supporting said sleeve element thereupon in coaxial relation and extending therebetween and being integrally formed therewith; and (3) a plurality of spaced latching members intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a rigid but elastic lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom to a crest and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; (7) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (8) each said lever member having a readily accessible lip portion disposed radially outward from said crest of said latch element and extending axially therefrom toward the remainder of the pipe a distance equal to at least one-half the axial width of one of said ribs.

Claim 28

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being inflexible and being rigid but elastic throughout and formed of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a cylindrical rigid, inflexible, but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar connected to the end of said wall structure of the remainder of the pipe in supported relation and supporting said sleeve element thereupon in coaxial relation and extending therebetween and being integrally formed therewith; and (3) a plurality of spaced latching members intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a rigid but elastic lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom to a crest and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; (7) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (8) each said lever member having a readily accessible lip portion disposed radially outward from said crest of said latch element and extending axially therefrom toward the remainder of the pipe a distance equal to at least one-half the axial width of one of said ribs.

Claim 29

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being inflexible and being rigid but elastic throughout and formed of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a cylindrical rigid, inflexible, but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar connected to the end of said wall structure of the remainder of the pipe in supported relation and supporting said sleeve element thereupon in coaxial relation and extending therebetween and being integrally formed therewith; and (3) a plurality of spaced latching members intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a rigid but elastic lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; (7) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (8) each said lever member having a readily accessible axially extending lip portion disposed between said latching surface and the tip of said lever member, said lip portion extending at least to the center of one of said ribs of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element.

Claim 30

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being inflexible and being rigid but elastic throughout and formed of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a cylindrical rigid, inflexible, but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar connected to the end of said wall structure of the remainder of the pipe in supported relation and supporting said sleeve element thereupon in coaxial relation and extending therebetween and being integrally formed therewith; and (3) a plurality of spaced latching members intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a rigid but elastic lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; (7) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (8) each said lever member having a readily accessible axially extending lip portion disposed between said latching surface and the tip of said lever member, said lip portion extending at least to the center of one of said ribs of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element.

Claim 31

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being inflexible and being rigid but elastic throughout and formed of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a cylindrical rigid, inflexible, but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar connected to the end of said wall structure of the remainder of the pipe in supported relation and supporting said sleeve element thereupon in coaxial relation and extending therebetween and being integrally formed therewith; and (3) a plurality of spaced latching members intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a rigid but elastic lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; (7) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (8) each said sleeve element having a plurality of axially spaced successive annular ribs disposed on its external surface adjacent said latching members.

Claim 32

Large-diameter corrugated plastic pipe having inherent non-releasable coupling means readily accessible from the exterior when coupled to other pipe, said pipe comprising: (a) a pipe having a generally cylindrical corrugated, relatively inflexible, rigid but elastic wall structure with spaced apart successive annular ribs with annular valley portions therebetween; (b) said wall structure being inflexible and being rigid but elastic throughout and formed of high density polyethylene and extending from adjacent one end portion of the pipe and throughout the remainder of the pipe; (c) said end portion comprising: (1) a cylindrical rigid, inflexible, but elastic sleeve element integrally formed with said wall structure and having an inner diameter exceeding only slightly the outer diameter of said ribs; (2) a support collar connected to the end of said wall structure of the remainder of the pipe in supported relation and supporting said sleeve element thereupon in coaxial relation and extending therebetween and being integrally formed therewith; and (3) a plurality of spaced latching members intermediate the ends of said sleeve element and integrally formed therewith and each extending inwardly therefrom around its interior in the same transverse plane relative thereto, the radial distance from the inner end of said latching members to the axis of said sleeve element being less than the radius of said ribs; (4) each of said latching members being comprised of a rigid but elastic lever member supported at its fulcrum by said sleeve element and formed integrally therewith and extending in the plane thereof from its fulcrum toward the remainder of the pipe and being free at its tip and along each of its sides to permit same to flex at its fulcrum along a circumferential line of said sleeve element; (5) each of said lever members carrying a latch element which extends inwardly therefrom and has a latching surface adjacent the tip of its associated lever member extending radially of said sleeve element and facing toward the remainder of the pipe; (6) each of said lever members also having a camming surface located outwardly of said latching surface and extending radially inwardly relative to said sleeve element from a point adjacent the fulcrum of said lever member to its said latching surface; (7) said latching elements being constructed, arranged and located on said sleeve element so that the latching surfaces thereof extend into and engage in latching relation valley-defining portions of a similarly constructed pipe when the end of the remainder portion of such a pipe is thrust into the outer end of said sleeve element; (8) each said sleeve element having a plurality of axially spaced successive annular ribs disposed on its external surface adjacent said latching members.