US3732046A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dimensional control apparatus
Assignee: Advanced Drainage Systems Inc
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Filing: 1971-03-22
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Granted: 1973-05-08
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Expires: 1991-03-22
Abstract
Abstract Apparatus and method control dimensions of corrugated tubing by stretching tubing predetermined amount as it travels between molding unit and downstream pulling assembly running at about same rate tubing is discharged from molding unit. First counter mechanism adjacent discharge end of molding unit counts predetermined number of corrugations in tubing and immediately thereafter generates signal indicating that predetermined number has been counted. Generation of signal from first counter triggers signal from second counter mechanism indicative of number of corrugations passing pulling assembly. Signal from second counter indicates more than predetermined number of corrugations has been counted, less than predetermined number has been counted, or count substantially equal to predetermined number. When more than predetermined number of corrugations is counted speed of pulling assembly is incrementally decreased to lessen stretch of tubing, and conversely, when less than predetermined number is counted speed of pulling assembly is incrementally increased to increase stretch of tubing. Second counter mechanism is initially adjusted so that no signal is generated by second counter when tubing between molding unit and pulling assembly is stretched predetermined amount.
Inventors
- 👤 R Martin
- 👤 M Sixt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:44
CPC Classifications
B; B29; B29C; B29C49/00; B29C49/0015; B29C49/0021; H; H02; H02P; H02P5/00; H02P5/46; H02P5/50; H02P5/51; B29C2793/00; B29C2793/0045; B29C2793/009
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
297 words
An apparatus for continuously producing corrugated tubing comprising a molding unit, an assembly downstream of the molding unit for pulling the tubing from the molding unit at substantially the same rate it is discharged from the molding unit, and a system for controlling the dimensions of the tubing by stretching the tubing a predetermined amount as it travels between the molding unit and the pulling assembly, and wherein the dimensional control system includes first counter means upstream of the pulling assembly adjacent the discharge end of the molding unit arranged to count a predetermined number of corrugations in the tubing and immediately thereafter generate a signal indicating that the predetermined number has been counted, second counter means associated with the pulling assembly arranged to count the number of corrugations in the tubing passing the pulling assembly and generate an advance signal, a retard signal or a null signal when the signal from the first counter means is generated, an advance signal indicating that substantially less than the predetermined number of corrugations has been counted by the second counter means, a retard signal indicating that substantially more than the predetermined number of corrugations has been counted by the second counter means, and a null signal indicating that substantIally the predetermined number of corrugations has been counted by the second counter means, speed changer means connected to the pulling assembly for incrementally altering the speed of that assembly in response to advance and retard signals, an advance signal causing an incremental increase and a retard signal causing an incremental decrease in the speed of the pulling assembly, and means for initially adjusting the second counter means so that the null signal is generated when the tubing between the molding unit and the pulling assembly is stretched the predetermined amount.
Claim 2
Independent Claim
297 words
An apparatus for continuously producing corrugated tubing comprising a molding unit, an assembly downstream of the molding unit for pulling the tubing from the molding unit at substantially the same rate it is discharged from the molding unit, and a system for controlling the dimensions of the tubing by stretching the tubing a predetermined amount as it travels between the molding unit and the pulling assembly, and wherein the dimensional control system includes first counter means upstream of the pulling assembly adjacent the discharge end of the molding unit arranged to count a predetermined number of corrugations in the tubing and immediately thereafter generate a signal indicating that the predetermined number has been counted, second counter means associated with the pulling assembly arranged to count the number of corrugations in the tubing passing the pulling assembly and generate an advance signal, a retard signal or a null signal when the signal from the first counter means is generated, an advance signal indicating that substantially less than the predetermined number of corrugations has been counted by the second counter means, a retard signal indicating that substantially more than the predetermined number of corrugations has been counted by the second counter means, and a null signal indicating that substantIally the predetermined number of corrugations has been counted by the second counter means, speed changer means connected to the pulling assembly for incrementally altering the speed of that assembly in response to advance and retard signals, an advance signal causing an incremental increase and a retard signal causing an incremental decrease in the speed of the pulling assembly, and means for initially adjusting the second counter means so that the null signal is generated when the tubing between the molding unit and the pulling assembly is stretched the predetermined amount.
Claim 3
Dependent Claim
61 words
An apparatus as in claim 1 wherein the first counter means includes a rotatable scanning wheel with peripherally arranged teeth in driving arrangement with the corrugations in the tubing, and means associated with the rotatable scanning wheel that causes the first signal to be generated after a predetermined number of teeth on the wheel have been driven by the corrugated tubing.
Claim 4
Dependent Claim
109 words
An apparatus as in claim 2 wherein the means associated with the rotatable scanning wheel for causing generation of the first signal comprises a photoelectric cell on one side of the scanning wheel, a light source on the other side of the wheel in alignment with the photoelectric cell, and a plurality of openings in the scanning wheel equally spaced from each other and the periphery of the wheel, the openings rotating in a path of travel which causes the light source to strike the photoelectric cell and thereby generate a first signal after the predetermined number of teeth on the wheel have been driven by the corrugated tubing.
Claim 5
Dependent Claim
36 words
An apparatus as in claim 3 wherein the plurality of openings in the scanning wheel comprise four in number whereby four signals from the first counter means are generated for each revolution of the scanning wheel.
Claim 6
Dependent Claim
30 words
An apparatus as in claim 1 wherein the predetermined amount of stretch equals the shrinkage of the tubing upon cooling per unit length plus an additional amount per unit length.
Claim 7
Independent Claim
109 words
An apparatus for continuously producing corrugated tubing comprising a molding unit, an assembly downstream of the molding unit for pulling the tubing from the molding unit at substantially the same rate it is discharged from the molding unit, and a system for controlling the dimensions of the tubing by stretching the tubing a predetermined amount as it travels between the molding unit and the pulling assembly, and wherein the dimensional control system is arranged to stretch the tubing in a linear direction a predetermined amount equal to the amount of shrinkage of the tubing upon cooling plus a slight additional amount for maintaining the tubing under tension during processing.
Claim 8
Independent Claim
109 words
An apparatus for continuously producing corrugated tubing comprising a molding unit, an assembly downstream of the molding unit for pulling the tubing from the molding unit at substantially the same rate it is discharged from the molding unit, and a system for controlling the dimensions of the tubing by stretching the tubing a predetermined amount as it travels between the molding unit and the pulling assembly, and wherein the dimensional control system is arranged to stretch the tubing in a linear direction a predetermined amount equal to the amount of shrinkage of the tubing upon cooling plus a slight additional amount for maintaining the tubing under tension during processing.
References Cited (Backward Citations)
US3212127A
Cited
US3400426A
Cited
US3280430A
Cited
US3531827A
Cited
US3438089A
Cited
US3530536A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-07 | 1976-11-06 | 1977-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-07 | 1980-11-06 | 1981-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-07 | 1984-11-06 | 1985-05-08 | $7700.00 | Window Closed / Lapsed |