Method and apparatus for controlling dynamic instability in axially moving form
US4663097A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 22, 1985 |
| Grant date | May 5, 1987 |
| Priority date | — |
| Expiry date | Aug 22, 2005 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2948/92923
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for controlling induced dynamic instability in an axially moving form supported between two axially spaced supports wherein the form is relatively soft and therefore exposed to development of transverse tensional forces tending to pivot the form about one or both supports. Control is effected by establishing a datum axis, repeatedly sensing the lateral position of the form in at least two mutually inclined transverse directions, deriving signals proportional to the sensed lateral displacement of the form from the datum axis, converting the signals to thrust forces, and applying the thrust forces to restore the form to the desired lateral position. The technique is of particular value in the production of oriented polymeric tubular films.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.