Power Supply Segmentation for Overcurrent Data Preservation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing image processing apparatuses lose data due to immediate power shutdown when an overcurrent occurs, as they lack a mechanism to execute finish processing before stopping power supply to the master CPU.

Innovation Solution

An image forming apparatus with a detection unit that identifies overcurrents in the second power supply unit, allowing the power source control unit, supplied by the first power supply, to shut off power to the second device and execute finish processing for the first device, ensuring data preservation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a protective circuit shuts off power supply immediately when an overcurrent flows, then the harmful effect of overcurrent is eliminated, but data loss occurs because finish processing cannot be executed

Engineering Contradiction:

Improveprotection against overcurrentVSAvoiddata loss

Core Design Contradiction:

ReliabilityVSLoss of information

Solution Approach 1:

The power supply system is divided into two independent power supply units: a first power supply unit that supplies power to the control unit and a second power supply unit that supplies power to other devices. This segmentation allows the protective circuit to shut off only the second power supply unit when an overcurrent is detected, while the first power supply unit continues to supply power to the control unit, enabling finish processing to be executed without data loss.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The first power supply unit acts as an intermediary that provides backup power to the control unit during overcurrent events. When the second power supply unit detects an overcurrent and shuts off, the first power supply unit maintains power supply to the control unit, allowing it to continue executing finish processing and save data before the entire system shuts down.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Object-affected harmful factors

If power supply is stopped immediately to protect against overcurrent, then device safety is improved, but the control unit cannot complete data saving processing

Engineering Contradiction:

Improveovercurrent damageVSAvoidunsaved data

Core Design Contradiction:

Object-affected harmful factorsVSLoss of information

Solution Approach 1:

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The control unit is designed to execute finish processing and save data as a preliminary action before the complete system shutdown occurs. When an overcurrent is detected, the second power supply unit is shut off first, but the control unit continues to operate on power from the first power supply unit to complete data saving processing before the entire system shuts down.

Inventive Principle:

Principle #10Preliminary action

3Power

If the second power supply unit maintains output voltage during a short circuit, then power delivery is maintained, but excessive current causes damage

Engineering Contradiction:

Improvepower deliveryVSAvoidexcessive current

Core Design Contradiction:

PowerVSObject-affected harmful factors

Solution Approach 1:

A protective circuit is provided that detects overcurrent conditions in the second power supply unit and provides feedback to shut off the second power supply unit when an overcurrent is detected. This feedback mechanism allows the system to maintain normal power delivery during operation while automatically shutting off the second power supply unit when a short circuit or other overcurrent condition occurs, preventing excessive current damage.

Inventive Principle:

Principle #23Feedback

4Device complexity

If a single power supply unit is used, then device complexity is reduced, but selective power shutdown during overcurrent is not possible

Engineering Contradiction:

Improvepower supply structureVSAvoidselective power shutdown capability

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The power supply system is divided into two independent power supply units: a first power supply unit that supplies power to the control unit and a second power supply unit that supplies power to other devices. This segmentation enables selective power shutdown capability, allowing the protective circuit to shut off only the second power supply unit when an overcurrent is detected, while the first power supply unit continues to supply power to the control unit for safe data saving and shutdown processing.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS9417593B2Image forming apparatus configured to switch between supplying and shutting-off of power to a portion of the image forming apparatus

Publication Date: 2016.08.16 CANON KK

AI summary

An image forming apparatus includes a first power supply unit to output first output power, a first device to which the first output power is supplied, a second power supply unit to output second output power, a second device to which the second output power is supplied, a detection unit to detect an overcurrent of the second power supply unit, a power source control unit to which the first output power is supplied and to switch between supplying and shutting-off of the second output power to the second device, and a control unit to which the first output power is supplied and to control an operation of the power source control unit. When the detection unit detects an overcurrent of the second output power, the power source control unit shuts off the second output power to the second device, and the control unit executes finish processing for the first device.