Document Detection Sensor for Access Cover State Judgment

Solution Overview

Problem

Existing image forming devices require a dedicated access detection scheme to detect the access state of the upper cover, which increases costs and occupies space.

Innovation Solution

The image forming device incorporates a document placement detector with a document detection lever and a light blocking body, which interlock with a document detection sensor to determine the access cover state, allowing the controller to judge the access cover state without a dedicated access detection scheme.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a dedicated access detection scheme is provided to detect the access state of the upper cover, then the access state can be accurately detected, but the cost and space requirements increase

Engineering Contradiction:

Improveaccess state detection accuracyVSAvoiddetection scheme complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The document detection sensor is designed to serve dual purposes: it detects both the presence of documents on the document tray and the access state of the upper cover. By making the detection system universal, the patent eliminates the need for a separate dedicated access detection scheme, thereby reducing device complexity and cost while maintaining reliable detection accuracy

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges the access detection function with the document detection function into a single integrated system. The document detection sensor and document detection lever are combined to perform both document presence detection and cover access state detection, consolidating multiple detection functions into one unified mechanism

Inventive Principle:

Principle #5Merging (Combining)

2Reliability

If a dedicated access detection scheme is provided to detect the access state of the upper cover, then the access state can be accurately detected, but the space required increases

Engineering Contradiction:

Improveaccess state detection accuracyVSAvoiddetection scheme space

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The document detection sensor is designed to serve dual purposes: it detects both the presence of documents on the document tray and the access state of the upper cover. By making the detection system universal, the patent eliminates the need for a separate dedicated access detection scheme, thereby reducing device complexity and cost while maintaining reliable detection accuracy

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges the access detection function with the document detection function into a single integrated system. The document detection sensor and document detection lever are combined to perform both document presence detection and cover access state detection, consolidating multiple detection functions into one unified mechanism

Inventive Principle:

Principle #5Merging (Combining)

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 enables the image forming device to omit the dedicated access detection scheme, resulting in cost and space savings while effectively judging the access cover state.

Implementation Method 1

a light blocking body to be displaced to a light blocking position where light emitted from the light emitter toward the light receiver of the document detection sensor is blocked

Methodology Applied

Scientific EffectLight blocking: Absorption (EM radiation)

Data Source

PatentUS20250126217A1Image forming device

Publication Date: 2025.04.17 SHARP KK

AI summary

When a light blocking body is located at a light blocking position where light emitted from a light emitter toward a light receiver of a document detection sensor is blocked, the document detection sensor is set to be in a light blocking state in which the emitted light is blocked. When the light blocking body is located at a light receiving position to make it possible for the light emitted from the light emitter toward the light receiver of the document detection sensor to be received, the document detection sensor is set to be in a light receiving state in which the emitted light is received. A controller judges that, when the document detection sensor is in the light receiving state, an access cover is opened or the access cover is closed and a document is not placed on a document tray, and judges that, when the document detection sensor is in the light blocking state, the access cover is closed and the document is placed on the document tray.