Optical Scanner Airflow Deflection for Thermal Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In optical scanning apparatuses, high-temperature air generated by a rotating polygonal mirror causes temperature rises in the side walls and supporting portions of the scanning optical system, leading to warpage and irradiation position fluctuations, especially in multi-color image forming apparatuses, resulting in color misregistration.
Innovation Solution
The optical scanning apparatus includes a light source positioned on the side wall, a supporting portion on the bottom, a cover member, a first air current deflecting portion to direct air from the rotating polygonal mirror towards the bottom, and a second air current deflecting portion on the cover member to redirect the air across the longitudinal direction, effectively distributing heat away from the side walls and supporting portions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the scanning optical system is disposed in the neighborhood of the deflector for compact installation, then the device complexity is reduced, but the temperature of the side wall of the optical box and the supporting portions increases, causing irradiation position fluctuations
Solution Approach 1:
The patent extracts the harmful hot air flow from the vicinity of the scanning optical system by introducing a deflector that redirects the air current generated by the rotating polygonal mirror toward the light source. This separates the thermal management function from the optical scanning function, allowing compact installation while preventing temperature-induced position deviations.
Solution Approach 2:
The patent introduces a deflector as an intermediary component between the polygonal mirror and the scanning optical system. This deflector acts as a mediator that redirects the hot air flow path without interfering with the optical path, enabling both compact installation and precise irradiation positioning.
2Productivity
If the rotatable polygonal mirror rotates at high speed for continuous scanning, then the productivity is improved, but the deflector becomes high in temperature, generating high-temperature air that causes warpage and position fluctuations
Solution Approach 1:
The patent converts the harmful effect of high-temperature air generation into a beneficial flow direction control. By using the deflector to redirect the hot air flow toward the light source, the patent utilizes the existing thermal energy and air movement to cool the deflector area while preventing the air from heating the scanning optical system, thereby maintaining both high scanning speed and temperature control.
3Device complexity
If the scanning optical system is positioned close to the deflector, then the device complexity is reduced, but the air current from the deflector blows against the side wall and spreads throughout the optical box, causing temperature rise in supporting portions
Solution Approach 1:
The patent extracts the hot air current from the general optical box environment by redirecting it specifically toward the light source area. This prevents the hot air from spreading throughout the optical box and heating the supporting portions of the scanning optical system, while maintaining the compact arrangement of components.
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 temperature fluctuations and irradiation position deviations, minimizing color misregistration by uniformly distributing the warmed air and preventing temperature rises in critical areas.
Implementation Method 1
a deflector including a rotatable polygonal mirror for deflecting the light beam emitted from the light source
Implementation Method 2
a first air current deflecting portion configured to deflect, to a direction from the bottom toward the cover member, an air current generated by rotation of the rotatable polygonal mirror
Implementation Method 3
a second air current deflecting portion provided on the cover member and configured to deflect, to a direction crossing the longitudinal direction, the air current deflected by the first air current deflecting portion
Data Source
AI summary
An optical scanning apparatus includes a light source, a deflector, an optical member, a supporting portion, a casing, a cover member, a first air current deflecting portion configured to deflect, to a direction from the bottom toward the cover member, an air current generated by rotation of the rotatable polygonal mirror and flowing along a longitudinal direction of the optical member; and a second air current deflecting portion provided on the cover member and configured to deflect, to a direction crossing the longitudinal direction, the air current deflected by the first air current deflecting portion and flowing in the longitudinal direction.