Patent · US Expired

Transition monitor for a unit transition counter

US3932738A · kind A · utility

4Cited by
1References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 9, 1975
Grant dateJan 13, 1976
Priority date
Expiry dateJan 9, 1995

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B2219/34466
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

Input data from an XY encoder stage is continuously monitored and compared to an internally generated count as the stage is adjusted in position. The internal count is generated a single count at a time by transitions in the X-Y input data on the basis that each transition is a one-step change in encoder position. A series of one-step transitions causes both the input data and the internal count to change together, or track. If a single transition is greater than a single encoder step, the input data advances ahead of the internal count and tracking is lost, causing a comparison error. The error halts the monitoring process, activates an alarm, and holds the current input data and internal count for visual comparison in a numerical display. The operator can then remonitor the faulty portion of the stage encoder to determine the nature of the error. The transition monitor is provided with internal testing circuit for counting up and down, changing counting directions, and detecting a prewired multistep test error.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.