Patent · US Expired

Variable temperature recording stylus

US4139854A · kind A · utility

6Cited by
3References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 21, 1977
Grant dateFeb 13, 1979
Priority date
Expiry dateNov 21, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D15/10
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The resistive stylus in a thermographic strip chart recorder is connected by way of an adjustable selector switch to taps of an auxiliary secondary winding added to the D.C. inverter customarily used to power the recorder's pen motor. The amount of current to the stylus and thus the stylus temperature may be varied in accordance with recorder chart speed by adjusting the selector switch to connect the desired number of secondary winding turns to the stylus.

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