Patent · US Expired

Automatic adjusting device for adjusting platen gap

US5772339A · kind A · utility

9Cited by
9References
25Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 6, 1997
Grant dateJun 30, 1998
Priority date
Expiry dateJun 6, 2017

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB41J25/308
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

An automatic adjusting device for accurately adjusting a platen gap including an encoder 14 for outputting pulse signals in accordance with a moving distance of a carriage, a pulse width detector for detecting a pulse width of the pulse signal when the carriage is moved from a reference position in a direction of the platen, a difference calculator for calculating a difference between a pulse width of the pulse signal sent from the pulse width detector and a pulse width of a stored pulse signal, a contact detector for judging a contact position of the recording head with the platen surface by comparing the difference with the reference value, and a controller for controlling a platen gap in accordance with the thickness of a recording medium charged on the platen detected by a pulse signal sent from the encoder and a signal sent from the contact detector. A change in the pulse width caused by resistance on the carriage is subtracted by the difference detector to obtain correction data so that the contact point can be accurately detected.

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