Dynamic Motor Current Limiting for Continuous Sheet Feeding

Solution Overview

Problem

Ink-jet recording apparatuses face challenges in reducing power consumption and using lower-capacity power sources while maintaining throughput during continuous recording processing, as existing solutions require high-capacity power sources and motors to handle peak loads, leading to increased costs and potential throughput deterioration.

Innovation Solution

A serial-type recording apparatus with a controller that manages three motors to perform intermittent conveyance and image recording alternately, using different current limit values for each motor to optimize power usage, allowing for continuous recording before completing image processing on the first sheet, and refeeding the second sheet using a larger current limit value only when necessary.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If a large-capacity power source and motor driver are incorporated to meet the total current limit values of all motors during continuous recording processing, then the power consumption capacity is sufficient, but the apparatus cost increases

Engineering Contradiction:

Improvepower consumption capacityVSAvoidapparatus cost

Core Design Contradiction:

PowerVSEase of manufacture

Solution Approach 1:

The patent applies dynamics by making the current limit value of the first motor changeable based on operational conditions. The controller dynamically switches between a first current limit value (when the second sheet is fed before first sheet recording completes) and a second current limit value (when the second sheet is fed after first sheet recording completes). This allows the power source capacity to be sized for the less demanding scenario while still handling peak loads when necessary, reducing overall apparatus cost while maintaining sufficient power capacity for continuous recording operations.

Inventive Principle:

Principle #15Dynamics

2Productivity

If the second sheet is fed from the sheet feeding part before completion of image recording on the first sheet, then the throughput is improved, but the total current consumption exceeds the power source capacity

Engineering Contradiction:

ImprovethroughputVSAvoidtotal current consumption

Core Design Contradiction:

ProductivityVSUse of energy by moving object

Solution Approach 1:

The patent resolves this contradiction by dynamically adjusting the current limit value of the first motor based on the timing of sheet feeding operations. When the second sheet is fed before the first sheet recording completes (continuous recording mode), the controller sets the first motor's current limit to a lower first current limit value, ensuring total current consumption remains within power source capacity. When the second sheet is fed after first sheet recording completes, the controller increases the current limit to a higher second current limit value, allowing the motor to handle greater loads. This dynamic adjustment enables continuous recording processing without exceeding power source capacity.

Inventive Principle:

Principle #15Dynamics

3Power

If the current limit value of the first motor is reduced to lower power consumption, then the power source capacity can be smaller, but the feed reliability of the second sheet deteriorates

Engineering Contradiction:

Improvepower consumptionVSAvoidfeed reliability

Core Design Contradiction:

PowerVSReliability

Solution Approach 1:

The patent applies dynamics by making the current limit value of the first motor changeable based on operational conditions. The controller dynamically switches between a first current limit value (when the second sheet is fed before first sheet recording completes) and a second current limit value (when the second sheet is fed after first sheet recording completes). This allows the power source capacity to be sized for the less demanding scenario while still handling peak loads when necessary, reducing overall apparatus cost while maintaining sufficient power capacity for continuous recording operations.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The controller determines in advance whether continuous recording processing will be performed and pre-sets the appropriate current limit value for the first motor. When continuous recording is detected (second sheet fed before first sheet recording completes), the controller sets the first current limit value before the feeding operation begins, ensuring reliable feeding while staying within power source capacity. This preliminary action prevents feed reliability issues that would occur with a permanently reduced current limit.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS10166793B2Serial-type recording apparatus

Publication Date: 2019.01.01 BROTHER KOGYO KK

AI summary

A serial-type recording apparatus includes a controller configured to execute continuous recording processing in which, before completion of image recording on a first sheet fed before a second sheet, the second sheet is fed from a feed tray, wherein the controller is configured to: set a first current limit value in a first motor and drive the first motor having the first current limit value to feed the second sheet from the feed tray; and set a second current limit value in the first motor and drive the first motor having the second current limit value to refeed the second sheet from the feed tray, on condition that driving of a second motor has completed a last intermittent conveyance of the first sheet and feed failure of the second sheet has been determined based on a detection signal from a sheet sensor.