Patent US3650868A successfully refreshed from Google Patents.
US3650868A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods and apparatus for manufacturing pipe-shaped articles from foamed thermoplastic resin
Assignee: Furukawa Electric Co Ltd
•
Filing: 1969-03-20
•
Granted: 1972-03-21
•
Expires: 1989-03-20
Abstract
Abstract Methods and apparatus for manufacturing pipe-shaped articles from foamed thermoplastic resin which comprise turning the foamed thermoplastic resin sheet such as foamed polyethylene, foamed polypropylene, or foamed polyvinyl chloride, heating the abutting or contacting surfaces of the sheet and joining the sheet.
Inventors
- 👤 George Murota
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:05
CPC Classifications
B; B29; B29C; B29C67/00; B29C67/0014; B29C44/00; B29C44/34; B29C44/56; B29C44/5627; B29C44/5636; B29C53/00; B29C53/36; B29C53/38; B29C53/48; B29C65/00; B29C65/02; B29C66/00; B29C66/01; B29C66/05; B29C66/10; B29C66/11; B29C66/112; B29C66/1122; B29C66/114; B29C66/1142; B29C66/40; B29C66/41; B29C66/43; B29C66/432; B29C66/4322; B29C66/4329; B29C66/49; B29C66/70; B29C66/72; B29C66/727; B29C66/73; B29C66/739; B29C66/7392; B29C66/73921; B29C65/10; B29C65/103; B29C65/106; B29C65/14; B29C65/1403; B29C65/1412; B29C65/18; B29C65/40; B29C66/71; B29K; B29K2105/00; B29K2105/04; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1007; Y10T156/1008; Y10T156/1013; Y10T156/1036; Y10T156/1038
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
101 words
A method for continuously manufacturing a pipe-shaped article from foamed thermoplastic resin sheet which comprises continuously turning foamed thermoplastic resin sheet so as to bring its longitudinal side faces close to each other or into contact with each other, said turned sheet exhibiting internal forces tending to return said sheet back to its un-turned form, heating said side faces, applying pressure so as to contact said side faces fully with each other, and maintaining the state of said sheet with said side faces maintained in contact until said side faces are firmly joined by cooling, thereby to produce a pipe-shaped article.
Claim 2
Independent Claim
84 words
A method for continuously manufacturing a pipe-shaped article from foamed thermoplastic resin sheet which comprises continuously turning foamed thermoplastic resin sheet so as to bring its longitudinal side faces into face-to-face contact with each other, said turned sheet exhibiting internal forces tending to return said sheet back to its un-turned form, continuously heating said side faces, applying pressure to compress said turned sheet flat and, after fusion, maintaining said flatly compressed state until said side faces are cooled sufficiently to be firmly joined together.
Claim 3
Dependent Claim
17 words
The method according to claim 2 wherein the foamed thermoplastic resin sheet is turned over a core.
Claim 4
Dependent Claim
26 words
The method according to claim 2 wherein the foamed thermoplastic resin sheet is turned over a core to form a composite pipe-shaped article containing the core.
Claim 5
Dependent Claim
12 words
The method according to claim 5 wherein the core is a rod.
Claim 6
Dependent Claim
15 words
The method according to claim 5 wherein the core is covered with heat resistant material.
Claim 7
Independent Claim
71 words
A method for manufacturing a multilayer pipe-shaped article from a foamed thermoplastic resin sheet which comprises: winding the sheet about the outer circumference of a core, said wound sheet exhibiting internal forces tending to return said sheet back to its un-wound form, and heating at least one of two contact surfaces of adjacent layers of the sheet immediately prior to joining of said contact surfaces, to form a multilayer pipe-shaped article.
Claim 8
Independent Claim
108 words
A method for continuously manufacturing a multilayer pipe-shaped article from foamed thermoplastic resin sheets which comprises: continuously helically winding a first sheet on the outer circumference of a core in a first direction, said wound sheet exhibiting internal forces tending to return said sheet back to its un-wound form; winding a second sheet on said wound first sheet in an opposite direction, said wound sheet exhibiting internal forces tending to return said sheet back to its un-wound form; and continuously heating at least one of two contact surfaces of the first and second sheets immediately prior to joining of said contact surfaces, to form a multilayer pipe-shaped article.
Claim 9
Dependent Claim
43 words
The method according to claim 1 wherein the foamed material of thermoplastic resin is a foam of a thermoplastic resin selected from the group consisting of polyolefin, olefin copolymers, cross-linked polyolefin, vinyl polymers, and natural rubbers and synthetic rubbers mixed with said polymers.
Claim 10
Dependent Claim
25 words
The method according to claim 1 wherein the inner surface of the pipe-shaped article of foamed thermoplastic resin is further lined with heat resistant material.
Claim 11
Dependent Claim
35 words
The method according to claim 2 wherein the molded pipe-shaped articles are heated to more than the softening temperature of the foamed resin and cooled to room temperature so as to eliminate the internal stress.
Claim 12
Independent Claim
100 words
An apparatus for continuously manufacturing a pipe-shaped article from a foamed thermoplastic resin sheet which comprises: a die for turning the foamed thermoplastic resin sheet so as to bring its longitudinal side faces into contact with each other, said turned sheet exhibiting internal forces tending to return said sheet back to its un-turned form; heating means for heating said side faces; a plurality of endless belts for maintaining said turned sheet in a condition having a flatly compressed cross section with its side faces pressed together until said side faces have sufficiently cooled to complete joining of said side faces.
Claim 13
Dependent Claim
38 words
The apparatus according to claim 13 comprising a guide roll located between said die and said endless belts for applying a stress to the foamed thermoplastic resin sheet to press the longitudinal side faces thereof against each other.
Claim 14
Independent Claim
135 words
An apparatus for continuously manufacturing a pipe-shaped article from a formed thermoplastic resin sheet which comprises: a die for turning the foamed thermoplastic resin sheet so as to bring its longitudinal side faces into contact with each other, said turned sheet exhibiting internal forces tending to return said sheet back to its un-turned form; heating means for heating said side faces of the sheet forwarded from the die; and a roll provided with a groove on the periphery thereof and an endless belt travelling through said groove receiving said heated and turned sheet and for applying a force thereto so as to maintain said turned sheet in a condition having a flatly compressed cross section with its side faces pressed together until said side faces have sufficiently cooled to complete joining of said side faces.
Claim 15
Dependent Claim
12 words
The method according to claim 5 wherein the core is a pipe.
Claim 16
Dependent Claim
12 words
The method according to claim 5 wherein the core is a wire.
Claim 17
Dependent Claim
29 words
The apparatus according to claim 13 comprising four endless belts respectively abutting the upper, lower and side surfaces of said turned sheet to maintain said flatly compressed cross section.
References Cited (Backward Citations)
CA671644A
Cited
US1944970A
Cited
US2936792A
Cited
US3279503A
Cited
US3497413A
Cited
US3366719A
Cited
US3400029A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-21 | 1975-09-20 | 1976-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-21 | 1979-09-20 | 1980-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-21 | 1983-09-20 | 1984-03-21 | $7700.00 | Window Closed / Lapsed |