Patent · US Expired

Digital indication type speedometer

US4368427A · kind A · utility

8Cited by
3References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 22, 1980
Grant dateJan 11, 1983
Priority date
Expiry dateDec 22, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01P3/489
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A digital indication type speedometer comprising a speed counter for counting speed pulses emitted in proportion to a vehicle speed for a given gate time, an indication register for latching a value to be indicated commensurate to an output from said speed counter and an indicator for indicating the value latched in said indication register is of such an arrangement that a hysteresis processing circuit is provided, which rewrites the value latched in said indication register in accordance with an output of said speed counter only when a difference between the output of said speed counter and the value latched in said indication register is not within tolerance limit upon comparison therebetween, so that response of the indication is excellent during acceleration or deceleration, and no flickering is observed during running at a constant speed.

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