Device for monitoring paper in typewriters and similar machines
Abstract
Abstract A device for monitoring paper feed movement in typewriters, printers or other paper-feeding apparatus, e.g. photocopiers wherein paper sheets inserted between a rotatable platen and pressure rollers are driven incident to rotation of the platen. A signal generator has a driving roll of the same size as the pressure rollers and axially aligned therewith which is prevented from being driven by the platen by the interposition of a narrow stationary belt positioned between the platen and drive roller adjacent one end of the platen. When paper is inserted a side edge passes between the belt and the drive roll and movement of the paper incident to platen rotation drives the drive roll of the pulse generator which monitors paper movement. If there is no paper movement due to paper jams or the end of a paper sheet is reached this condition is detected by the absence of pulses at the output of the pulse generator. The absence of pulse sequences serve to shut down the machine.
Inventors
- 👤 Richard Horman
- 👤 Wilfried Rettke
Bibliographic Details
Claims Analysis
Total Claims: 6References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-22 | 1989-01-21 | 1989-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-22 | 1993-01-21 | 1993-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-22 | 1997-01-21 | 1997-07-23 | $7700.00 | Window Closed / Lapsed |