Optical Scanning Light Blockers for Vibration Reduction

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing optical scanning devices experience noise and vibration issues due to airflow generated by rotating polygon mirrors, which affects the effectiveness of light blocking walls in preventing flare light from reaching photoconductors, leading to abnormal images and increased noise levels.

Innovation Solution

The optical scanning device employs a configuration of multiple light blocking walls disposed at specific angles and spacings relative to the rotation axis of the polygon mirrors, dispersing airflow and reducing wind pressure on each wall, thereby inhibiting elastic deformation and vibration, and effectively blocking flare light.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If multiple light blocking walls are disposed at specific angles and spacings, then noise and vibration are reduced, but device complexity increases

Engineering Contradiction:

Improvenoise and vibrationVSAvoidconfiguration complexity

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The patent divides a single light blocking wall into multiple segmented walls (at least two) disposed at different angular positions around the rotation axis. Each segment blocks flare light from a different angular range, and the segmentation allows airflow to pass through gaps between segments, reducing wind pressure and vibration on each individual segment while maintaining effective flare light blocking.

Inventive Principle:

Principle #1Segmentation

2Object-affected harmful factors

If light blocking walls are made larger to block more flare light, then flare light blocking effectiveness improves, but wind pressure and vibration on the walls increase

Engineering Contradiction:

Improveflare light blocking effectivenessVSAvoidwind pressure

Core Design Contradiction:

Object-affected harmful factorsVSForce

Solution Approach 1:

The light blocking structure is segmented into multiple walls distributed angularly around the rotation axis. This segmentation divides the total blocking area into smaller individual segments, each experiencing reduced wind pressure from the rotating polygon mirror, while the cumulative effect of all segments maintains effective flare light blocking.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent transitions from a single planar light blocking wall to a three-dimensional arrangement of multiple walls at different angular positions around the rotation axis. This spatial distribution in the angular dimension allows the system to block flare light from all angular directions while reducing the wind pressure on each individual wall segment.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Device complexity

If a single light blocking wall is used, then device complexity is minimized, but elastic deformation and vibration occur due to concentrated wind pressure

Engineering Contradiction:

Improvestructure simplicityVSAvoidstructural stability

Core Design Contradiction:

Device complexityVSStability of the object's composition

Solution Approach 1:

The single light blocking wall is segmented into multiple smaller walls disposed at different angular positions. This segmentation distributes the wind pressure load that would otherwise concentrate on a single wall, reducing elastic deformation and vibration while maintaining the overall light blocking function.

Inventive Principle:

Principle #1Segmentation

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 noise and vibration of the light blocking walls, preventing abnormal image formation and enhancing the scanning process by dispersing airflow and minimizing wind load on each blocker, resulting in improved image quality and reduced noise levels.

Implementation Method 1

airflow generated due to rotation of the polygon mirrors

Methodology Applied

Scientific EffectAirflow generation:

Implementation Method 2

block flare light from the optical element facing the deflector

Methodology Applied

Scientific EffectLight blocking: Absorption (EM radiation)

Data Source

PatentUS11747610B2Optical scanning device and image forming apparatus

Publication Date: 2023.09.05 RICOH CO LTD

AI summary

An optical scanning device includes light sources, a deflector, an optical element, and light blockers. The light blockers are spaced apart in a rotation direction of the deflector. An inequality θ1<θ2 is satisfied, where when viewed from the rotation axis direction, θ1 is an angle formed by a line segment connecting the end portion of a light blocker disposed most downstream in the rotation direction to a rotation axis center of the deflector and a line segment connecting the end portion of a light blocker disposed most upstream in the rotation direction to the rotation axis center, and θ2 is an angle formed by a line segment connecting an upstream end portion of one mirror surface in the rotation direction to the rotation axis center and a line segment connecting a downstream end portion of the one mirror surface in the rotation direction to the rotation axis center.