Rotor movement sensing system
US5389863A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 8, 1993 |
| Grant date | Feb 14, 1995 |
| Priority date | — |
| Expiry date | Feb 8, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07B2017/00548
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A rotor movement sensing system in a postage meter permits detection of the printing of postage even if power is lost during the printing cycle. A sensor senses a magnet on a disk when the rotor is substantially past its home position. A second sensor has a magnetic memory element. When the magnet on the disk passes near the memory element, that element is magnetized. A Hall-effect sensor at the memory element provides an interrupt to a processor to indicate magnetization of the memory element. A winding is provided around the memory element. The processor has an output which, when asserted, causes current flow through the winding, demagnetizing the memory element. Alternatively a reed switch senses rotor rotation, a flip-flop provides a bistable latch and its output provides a datum for the processor. An interrupt routine provides that during a routine franking cycle the processor responds to the interrupt, makes record in nonvolatile memory of the occurrence of the printing cycle, and energizes the winding or flip-flop reset. This interrupt routine is executed for each franking cycle when power is continuously available.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.