US 6,006,052 A · Fixing method and fixing device

Abstract

A fixing method for fixing an unfixed toner image formed on a recording material by transporting the recording material to a contact portion between a fixing roller and a pressurizing mechanism for pressurizing the surface of the fixing roller is arranged such that the fixing roller surface temperature and the pressurizing mechanism surface temperature at the contact portion while the recording material is being transported therethrough are controlled to fall within a non-offset region in which a sufficient fixing strength for fixing toner onto the recording material can be ensured without generating a high temperature offset, said non-offset region being defined by a critical border line obtained from a function of a fixing roller surface temperature and a pressurizing mechanism surface temperature. According to the described fixing method, an occurrence of an offset can be prevented without an application of an oil, and a toner fixing inferior can be prevented.

Claims24

Dependent claims

A fixing method for fixing an unfixed toner image formed on a recording material by transporting a recording material having formed thereon an unfixed toner image to a contact portion between fixing means and pressurizing means for pressurizing a surface of said fixing means, comprising the steps of:

(i) obtaining beforehand a non-offset region defined by a critical border line obtained from a function of a fixing means surface temperature and a pressurizing means surface temperature in which a sufficient fixing strength for fixing toner onto the recording material can be ensured without generating a high temperature offset;
and
(ii) controlling the fixing means surface temperature and the pressurizing means surface temperature at the contact portion while the recording material is being transported therethrough to fall within the non-offset region.

A fixing device comprising:

fixing means;
pressurizing means for pressurizing a surface of said fixing means;
heating means for heating said fixing means;
first temperature detection means for detecting a surface temperature of said fixing means in a vicinity of the contact portion, said first temperature detection means being provided in a vicinity of the contact portion of said fixing means;
second temperature detection means for detecting a surface temperature of said pressurizing means in a vicinity of the contact portion, said second detection means being provided in a vicinity of the contact portion of said pressurizing means;
and
heat application control means for controlling said heating means based on results of detection by said first temperature detection means and said second temperature detection means,
wherein said heat application control means controls the fixing means surface temperature and the pressurizing means surface temperature at the contact portion while the recording material is being transported therethrough within a non-offset region in which a sufficient fixing strength for fixing toner onto the recording material can be ensured without generating a high temperature offset, said non-offset region being defined by a critical border line obtained from a function of a fixing means surface temperature and a pressurizing means surface temperature.

5 more elements

Dependencies are inferred from the claim text.

Fixing method and fixing device

Life of this patent

Fixing method and fixing device

Life of this patent

Abstract

Claims24