Fixing Device Roller Hardness Adjustment Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing fixing devices for image forming apparatuses face challenges in maintaining a constant nip width and uniform printing results due to variations in the hardness of pressure rollers during replacement, requiring significant workload adjustments.
Innovation Solution
A fixing device with a biasing part, an adjusting part, and a guide indication part that adjusts the biasing force based on the hardness of the roller surface, using a screw and screw receiver mechanism to maintain consistent nip width, and includes a restricting member to limit adjustment range and a hardness identification system for precise adjustments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the hardness of a pressure roller is not controlled during replacement, then the pressing force remains the same, but the nip width changes leading to non-uniform printing results
Solution Approach 1:
The patent applies parameter changes by adjusting the biasing force of the biasing member according to the hardness of the pressure roller surface layer. When a new pressure roller is installed, the hardness is measured, and the biasing force is accordingly adjusted to maintain a constant nip width, ensuring uniform printing results across different roller replacements
2Manufacturing precision
If the biasing force is adjusted manually for each roller replacement, then the nip width can be maintained, but the workload increases significantly
Solution Approach 1:
The patent implements self-service by providing a hardness measurement guide that enables users to independently measure the hardness of the pressure roller surface layer and adjust the biasing force accordingly. This eliminates the need for complex automated adjustment systems while maintaining nip width consistency, thereby improving maintenance efficiency
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution reduces the workload required for maintaining a constant nip width during roller replacement and ensures consistent printing results by allowing for precise adjustments based on roller hardness, improving productivity and maintaining uniformity.
Implementation Method 1
The support shaft of the pressure roller of such a fixing device is rotatably supported by support arms, to which biasing members such as coil springs are attached. The biasing force of the biasing members allows the pressure roller to press the fixing roller at a given pressing force to maintain a constant nip width
Implementation Method 2
the adjusting part includes a screw and a screw receiver, to which the screw is fitted, and the biasing force of the biasing part is adjusted by rotation of the screw
Data Source
AI summary
A fixing device includes a pair of detachable rollers and applies heat and pressure to a sheet nipped between the rollers to fix a toner image formed on the sheet to the sheet. The fixing device includes a biasing part which gives a biasing force to bring one of the rollers into tight contact with the other, an adjusting part which adjusts the biasing force of the biasing part, and a guide indication part providing a guide for an amount of adjustment to be made by the adjusting part in accordance with the hardness of the surface layer of a roller of the rollers.