Blower Duct Airflow for Condensation Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Image forming apparatuses face issues with water vapor condensation leading to wet recording media and defective images in two-sided mode, and the perception of malfunction due to visible steam from the discharge opening.
Innovation Solution
An image forming apparatus with a blower that directs air from the downstream to the upstream side after reversing the recording material, using ducts with openings at the width direction of the recording material to guide airflow and prevent condensation on conveyance rollers and in the internal space.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the image forming apparatus operates at high speed and high productivity, then the recording medium remains high in temperature after passing through the fixing apparatus and releases more water vapor, but water droplets adhere to the reverse conveyance sheet passage and sheet passage, causing wet recording medium and defective images
Solution Approach 1:
The patent extracts and removes water vapor from the sheet passage by introducing a blower that actively draws water vapor away from the reverse conveyance sheet passage and sheet passage, preventing condensation on the recording medium during high-speed operation
Solution Approach 2:
The patent introduces air as an intermediary substance that flows through the sheet passage to carry away water vapor, acting as a mediator between the hot recording medium and the surrounding environment to prevent direct condensation
2Productivity
If the fixing apparatus generates a large amount of water vapor, then the water vapor remains in the internal space on the downstream side and exceeds the dew point, but minute water droplets (steam) become visible and exit through the sheet discharge opening, causing user misunderstanding of malfunction
Solution Approach 1:
The blower actively extracts and removes water vapor from the internal space on the downstream side of the fixing apparatus, preventing it from accumulating and exceeding the dew point, thereby eliminating visible steam formation
Solution Approach 2:
The blower operates continuously to maintain a steady flow of air through the sheet passage, continuously carrying away water vapor and preventing intermittent accumulation that would lead to visible steam
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
Prevents wetting of the recording medium, reduces defective images due to condensation, and eliminates visible steam from the discharge opening, thereby avoiding user misconceptions about apparatus malfunction.
Implementation Method 1
a blower means for blowing air; and a duct for guiding the air blown from the blower means to the reversing means, wherein the duct is provided with an opening at an end in a width direction of the recording material, and the blower blows the air from a downstream side to an upstream side in the feeding direction of the recording material after being reversed by the reversing portion
Implementation Method 2
While the recording medium and the unfixed image thereon are heated and pressed by the fixing apparatus, the moisture in the recording medium evaporates, and then, is released as water vapor, into or out of the fixing apparatus
Implementation Method 3
As the water vapor is released from the recording medium, it condenses on the guiding members of the image forming apparatus, which guide the recording medium as the recording medium is conveyed through the image forming apparatus. Further, it condenses on recording medium conveyance rollers
Data Source
AI summary
An image forming apparatus includes an image forming portion for forming a toner image on a sheet, a fixing portion for fixing the toner image formed by the image forming portion on the sheet, a reversing portion for reversing the sheet carrying the toner image fixed by the fixing portion, a blower for blowing air, and a duct for guiding the air blown from the blower to the reversing portion. The duct is provided with an opening at an end in a width direction of the sheet, and the blower blows the air from a downstream side to an upstream side with respect to the feeding direction of the sheet after being reversed by the reversing portion.