US3881754A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Resilient internal support for plastic pipe
Assignee: Individual
•
Filing: 1973-09-26
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Granted: 1975-05-06
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Expires: 1993-09-26
Abstract
Abstract An internal resilient support for reinforcing plastic pipe to prevent failure of the pipe externally adjacent its connection to a rigid pressure coupling or other pressure fitting comprising a helical member having contiguous convolutions and intimately surrounded by a separate semi-elastic sheath which limits flexure and/or deformation of the member whereby extensive bending of the support with the pipe is permitted without damage to either.
Inventors
- 👤 Joe William Christie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:23
CPC Classifications
F; F16; F16L; F16L35/00; F16L47/00; F16L47/04
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
221 words
In combination, a pressure coupling, a plastic pipe one end of which is clampingly confined in said pressure coupling, and an internal support within the confined end of the pipe, the support including a helical resilient member having contiguous convolutions and an external diameter slightly less than the internal diameter of said pipe, a sheath of semi-elastic thin material encasing the helical member and having its interior snugly engaging the exterior of the convolutions of said member so as to reduce the resiliency of the member only to the extent sufficient to prevent undue deformation thereof and of said pipe adjacent the coupling as well as excessive separation of said convolutions which might cause damaging of the sheath, said sheath being film-like and having a radial thickness much less than the wall thickness of said member, the sheath being free from attachment to said member and both said sheath and member being free from attachment to said pipe whereby said sheath and member may undergo restricted movement relative to each other and to said pipe, as may the convolutions of said member with respect to one another, and thereby amplify the area of deformation longitudinally of said support and pipe so as to prevent the creation of stress and flexures of small amplitude in said support and pipe adjacent said coupling.
Claim 2
Dependent Claim
221 words
In combination, a pressure coupling, a plastic pipe one end of which is clampingly confined in said pressure coupling, and an internal support within the confined end of the pipe, the support including a helical resilient member having contiguous convolutions and an external diameter slightly less than the internal diameter of said pipe, a sheath of semi-elastic thin material encasing the helical member and having its interior snugly engaging the exterior of the convolutions of said member so as to reduce the resiliency of the member only to the extent sufficient to prevent undue deformation thereof and of said pipe adjacent the coupling as well as excessive separation of said convolutions which might cause damaging of the sheath, said sheath being film-like and having a radial thickness much less than the wall thickness of said member, the sheath being free from attachment to said member and both said sheath and member being free from attachment to said pipe whereby said sheath and member may undergo restricted movement relative to each other and to said pipe, as may the convolutions of said member with respect to one another, and thereby amplify the area of deformation longitudinally of said support and pipe so as to prevent the creation of stress and flexures of small amplitude in said support and pipe adjacent said coupling.
Claim 3
Independent Claim
218 words
The method of reinforcing plastic pipe at its connection to a rigid pressure coupling or other pressure fitting comprising inserting into the interior of said plastic pipe at the end thereof connected into said pressure coupling an internal support comprising a helical resilient member having contiguous convolutions and an external diameter slightly less than the internal diameter of the pipe, and a sheath of semi-elastic thin material encasing the helical member and having its interior snugly engaging the exterior of the convolutions of said member so as to reduce the resiliency of the member only to the extent sufficient to prevent undue deformation thereof and of said pipe adjacent the coupling as well as excessive separation of said convolutions which might damage the sheath, said sheath being film-like and having a radial thickness much less than the wall thickness of the member, the sheath and member being free from attachment to each other and to said pipe whereby said sheath and member may undergo limited movement relative to each other and to said pipe, as may the convolutions of said member with respect to one another, and thereby amplify the area of deformation longitudinally of said support and pipe so as to prevent the creation of stress and acute flexures in said support and pipe adjacent said coupling.
Claim 4
Independent Claim
218 words
The method of reinforcing plastic pipe at its connection to a rigid pressure coupling or other pressure fitting comprising inserting into the interior of said plastic pipe at the end thereof connected into said pressure coupling an internal support comprising a helical resilient member having contiguous convolutions and an external diameter slightly less than the internal diameter of the pipe, and a sheath of semi-elastic thin material encasing the helical member and having its interior snugly engaging the exterior of the convolutions of said member so as to reduce the resiliency of the member only to the extent sufficient to prevent undue deformation thereof and of said pipe adjacent the coupling as well as excessive separation of said convolutions which might damage the sheath, said sheath being film-like and having a radial thickness much less than the wall thickness of the member, the sheath and member being free from attachment to each other and to said pipe whereby said sheath and member may undergo limited movement relative to each other and to said pipe, as may the convolutions of said member with respect to one another, and thereby amplify the area of deformation longitudinally of said support and pipe so as to prevent the creation of stress and acute flexures in said support and pipe adjacent said coupling.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |