US5207083A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of controlling the length of corrugated fins
Assignee: Delphi Technologies Inc
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Filing: 1991-12-06
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Granted: 1993-05-04
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Expires: 2011-12-06
Abstract
Abstract A center machine for producing corrugated fins for heat exchangers has servomotor driven pullout rolls for stretching a compressed corrugated strip to desired fin density and normally driven in phase with corrugation forming rolls. A cutoff knife severs parts from the strip and a sensor measures the length of each part. A control determines part length error, calculates servomotor speed adjustment needed to nearly correct the error and causes such a speed adjustment for a short period to alter the phase of the pullout rolls relative to the forming rolls.
Inventors
- 👤 Michael F. Bongiovanni
- 👤 Samuel Cicatello
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:04
CPC Classifications
B; B21; B21D; B21D13/00; B21D13/04
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
232 words
A method of using a machine for forming corrugated ribbon parts from sheet stock, said machine having forming rolls for corrugating the sheet stock, stuffing rolls for compressing the corrugated ribbon to a pitch smaller than the desired product pitch, metering rolls for feeding the compressed ribbon followed by pullout rolls driven by a servomotor for stretching the ribbon out to a desired nominal pitch, and cutter means following the pullout rolls for severing the ribbon into discrete parts; the method of accurately controlling the part length to a target length comprising the steps of: operating the servomotor to drive the pullout rolls in phase with the metering rolls to maintain the desired nominal pitch; measuring with high resolution the length of the most recently cut part; comparing the measured part length to the target part length to determine the amount of any error; determining from the error amount of the servomotor adjustment required to attain the target part length by multiplying the amount of error by a proportional gain constant to create a servomotor adjustment that is at least in part proportional to the error amount and which can correct said error without overshoot to create an opposite error; and correcting the error for subsequent parts by momentarily changing the servomotor speed according to the said motor adjustment to effect a phase change between the pullout rolls and the metering rolls.
Claim 2
Independent Claim
232 words
A method of using a machine for forming corrugated ribbon parts from sheet stock, said machine having forming rolls for corrugating the sheet stock, stuffing rolls for compressing the corrugated ribbon to a pitch smaller than the desired product pitch, metering rolls for feeding the compressed ribbon followed by pullout rolls driven by a servomotor for stretching the ribbon out to a desired nominal pitch, and cutter means following the pullout rolls for severing the ribbon into discrete parts; the method of accurately controlling the part length to a target length comprising the steps of: operating the servomotor to drive the pullout rolls in phase with the metering rolls to maintain the desired nominal pitch; measuring with high resolution the length of the most recently cut part; comparing the measured part length to the target part length to determine the amount of any error; determining from the error amount of the servomotor adjustment required to attain the target part length by multiplying the amount of error by a proportional gain constant to create a servomotor adjustment that is at least in part proportional to the error amount and which can correct said error without overshoot to create an opposite error; and correcting the error for subsequent parts by momentarily changing the servomotor speed according to the said motor adjustment to effect a phase change between the pullout rolls and the metering rolls.
Claim 3
Dependent Claim
75 words
The invention as defined in claim 1 wherein the step of determining the servomotor adjustment includes: multiplying the error amount by a proportional gain constant to obtain a first term; adding the error amount to a running sum of previous part lengths to update the running sum, and multiplying the updated running sum by an integral gain constant to obtain a second term; and summing the first and second terms to obtain the servomotor adjustment.
Claim 4
Dependent Claim
46 words
The invention as defined in claim 1 wherein the step of correcting the error comprises changing the servomotor speed for an empirically determined time period wherein the amount and sense of speed change is a function of the error amount and the sense of the error.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-05-03 | 1996-11-02 | 1997-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-05-03 | 2000-11-02 | 2001-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-05-03 | 2004-11-02 | 2005-05-04 | $7700.00 | Window Closed / Lapsed |