Patent US4028037A successfully refreshed from Google Patents.
US4028037A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tube treating and apparatus therefor
Assignee: Dow Chemical Co
•
Filing: 1976-05-26
•
Granted: 1977-06-07
•
Expires: 1996-05-26
Abstract
Abstract Synthetic resinous thermoplastic tubing is reduced radially in diameter with minimal increase in length by passing the tube through a plurality of successively smaller dies wherein a minor portion of the die moves relative to a major portion of the die during the reduction step. Plastic tube is obtained which has a tendency to expand radially with a minimal alteration in its length. Such tubing is particularly suitable for lining of pipe.
Inventors
- 👤 David H. Dawson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 08:25
CPC Classifications
B; B29; B29C; B29C55/00; B29C55/30; B29L; B29L2023/00; B29L2023/22
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
171 words
A tube diameter reducing apparatus, the tube diameter reducing apparatus comprising in cooperative combination a frame, the frame having a longitudinal axis, a plurality of die plates supported within the frame and selectively portionable therein, the die plates each defining a tube receiving opening, the tube receiving opening of the die plates being of generally successively decreasing diameter, the openings of the die plates being disposed in planes generally normal to the longitudinal axis, the openings of the die plates being generally coaxially disposed, means to: (a) selectively position the die plates along the axis of the frame, (b) provide sequential movement of a minor portion of the die plates relative to a major portion thereof, and (c) subsequently move each of the die plates relative to a major portion of the die plates whereby a tube on having a diameter approximately the diameter of the larger tube receiving opening the tube on being passed through the openings of decreasing diameter by the movement of die plates is reduced in diameter.
Claim 2
Dependent Claim
171 words
A tube diameter reducing apparatus, the tube diameter reducing apparatus comprising in cooperative combination a frame, the frame having a longitudinal axis, a plurality of die plates supported within the frame and selectively portionable therein, the die plates each defining a tube receiving opening, the tube receiving opening of the die plates being of generally successively decreasing diameter, the openings of the die plates being disposed in planes generally normal to the longitudinal axis, the openings of the die plates being generally coaxially disposed, means to: (a) selectively position the die plates along the axis of the frame, (b) provide sequential movement of a minor portion of the die plates relative to a major portion thereof, and (c) subsequently move each of the die plates relative to a major portion of the die plates whereby a tube on having a diameter approximately the diameter of the larger tube receiving opening the tube on being passed through the openings of decreasing diameter by the movement of die plates is reduced in diameter.
Claim 3
Dependent Claim
31 words
The apparatus of claim 1 wherein the means to selectively position to die plates along the axis of the frame, comprises a plurality of die actuating rods which engage a cam.
Claim 4
Dependent Claim
27 words
The apparatus of claim 2 wherein the die plates have a generally triangular peripheral configuration and each die plate is positioned by three die plate actuating rods.
References Cited (Backward Citations)
US3482007A
Cited
US3707086A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-06-06 | 1980-12-06 | 1981-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-06 | 1984-12-06 | 1985-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-06 | 1988-12-06 | 1989-06-07 | $7700.00 | Window Closed / Lapsed |