Sheet Guide Structure Thermal Management for Image Quality
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing image forming apparatuses suffer from the formation of contact marks or 'roller marks' on the images due to the high temperature of the recording medium when it comes into contact with the transport roller unit after being fixed by the fixing unit, as the guide members used to guide the sheet member from the fixing unit to the transport roller unit are made of similar thermal conductivity materials.
Innovation Solution
A sheet-member guide structure is introduced, comprising a first guide member made of a resin material with lower thermal conductivity and a second guide member made of a metal material with higher thermal conductivity, positioned downstream of the first guide member, to reduce heat transfer and dissipate heat effectively, thereby minimizing the temperature of the sheet member before it reaches the transport roller unit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If guide members are made of materials with similar thermal conductivities, then the structure is simple and easy to manufacture, but contact marks are formed on images due to high temperature transfer from the fixing unit to the transport roller unit
Solution Approach 1:
The guide members are designed with different thermal conductivity properties at different positions. The first guide member (near the fixing unit) has lower thermal conductivity to prevent heat transfer, while the second guide member (near the transport roller unit) has higher thermal conductivity to dissipate heat. This local differentiation of material properties resolves the contradiction between manufacturing simplicity and preventing contact marks.
Solution Approach 2:
The invention changes the thermal conductivity parameter of the guide members along the sheet transport path. By gradually increasing the thermal conductivity from the first guide member to the second guide member, the system controls temperature distribution to prevent contact marks while maintaining manufacturing feasibility through parameter optimization.
2Productivity
If the sheet member is transported directly from the fixing unit to the transport roller unit, then the transport path is short and efficient, but the sheet member remains at high temperature causing image distortion
Solution Approach 1:
The guide members act as intermediary elements between the fixing unit and the transport roller unit. They provide a controlled thermal interface that allows the sheet member to transition from high temperature to ambient temperature gradually, preventing direct high-temperature contact with the transport roller unit while maintaining an efficient transport path.
Solution Approach 2:
The guide structure is segmented into multiple guide members with different thermal conductivity characteristics. This segmentation allows different portions of the transport path to have different thermal management functions, enabling both efficient transport and adequate cooling of the sheet member.
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 reduces the occurrence of contact marks on the images by lowering the temperature of the sheet member before it contacts the transport roller unit, thereby enhancing the quality of the output images by minimizing thermal-induced image distortions.
Implementation Method 1
a first guide member (62) made of a resin material and disposed adjacent to the fixing unit (34)
Implementation Method 2
a second guide member (72) made of a metal material and disposed adjacent to the transport roller unit (48)
Data Source
AI summary
A sheet-member guide structure includes a first guide member that guides a sheet member from a fixing unit to a transport roller unit, the fixing unit fixing an image formed on the sheet member to the sheet member by heating the sheet member that is transported, the transport roller unit transporting the sheet member; and a second guide member that comes into contact with the sheet member to which the image has been fixed by the fixing unit and guides the sheet member to the transport roller unit, the second guide member being disposed downstream of the first guide member in a transporting direction in which the sheet member is transported and being made of a material having a thermal conductivity higher than a thermal conductivity of a material of the first guide member.