Fixing Device Roller Restriction Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In existing fixing devices, when handling paper jams, the movement of transport rollers to open the paper transport path can lead to foreign objects entering the heating member, potentially affecting image quality, and the device becomes larger due to the need for restriction members.
Innovation Solution
A fixing device with a torsion spring that biases the first transport roller towards the second, and a restriction portion that contacts the spring to prevent excessive movement, reducing the gap between rollers and minimizing the device's size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If one transport roller moves in the paper thickness direction to open the paper transport path for jam handling, then the paper transport path can be opened to remove jammed paper, but foreign objects will enter the paper transport path and become attached to the heating member, causing image quality decline
Solution Approach 1:
The restriction member is positioned to prevent excessive movement of the transport roller before foreign objects can enter the heating member. This preliminary restraint action stops the roller at a controlled position, preventing the harmful effect of foreign matter contamination while still allowing sufficient movement for jam handling operations
2Object-affected harmful factors
If the movement amount of one transport roller is restricted so that the gap between the pair of transport rollers does not increase too much, then foreign matter entry is suppressed, but the restriction member must be provided on the opposite side of the other transport roller with one transport roller interposed therebetween, making the device larger
Solution Approach 1:
The restriction member acts as an intermediary element that contacts the transport roller to limit its movement. By positioning this intermediary restraint component, the system achieves foreign matter entry suppression without requiring the transport roller to move excessively, thereby controlling device dimensions
3Productivity
If the gap between the pair of transport rollers is increased to facilitate paper transport, then paper transport is improved, but foreign objects can more easily enter the paper transport path during jam handling
Solution Approach 1:
The system allows dynamic adjustment of the gap between transport rollers during operation. During normal paper transport, the rollers maintain an optimal gap for efficient transport. During jam handling, the restriction member enables controlled movement to open the path, then returns to the original position to maintain the protective gap configuration, balancing both productivity and contamination prevention
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 configuration effectively prevents foreign matter from entering the heating member during jam handling while maintaining a compact device size by restricting the movement of the transport rollers, thus enhancing image quality and reducing the device's dimensions.
Implementation Method 1
a spring which includes a holding portion holding the rotation shaft of the first transport roller at one end side of the spring, a support portion supported by the frame at the other side of the spring and an arm part between the holding portion and the support portion, and is configured to bias the transport roller to the second transport roller
Data Source
AI summary
A fixing device includes: a frame forming a transport path; a heating member disposed on the transport path; first and second transport rollers which are disposed so as to face the heating member in the transport direction and hold the recording sheet between the first and second transport rollers to transport the recording sheet, the first transport roller including a rotation shaft; and a spring which includes a holding portion holding the rotation shaft of the first transport roller, a support portion supported by the frame and an arm part between the holding portion and the support portion, and is configured to bias the transport roller to the second transport roller; and a restriction portion which contacts a part of the spring between the holding portion and the support portion and restricts the first transport roller from being moved in a direction separated from the second transport roller.