Comb-Shaped Damper Unit for Inkjet Printer Paper Jam Prevention

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing recording apparatuses, such as ink jet printers, face the challenge of preventing paper jams due to the inertia of printing sheets climbing over separating bevels during rapid cassette insertion, which requires additional space for rotating and sliding mechanisms to align sheets properly, leading to printer upsizing and variations in damper force.

Innovation Solution

A damper unit with a comb-shaped first and second sliding surface, utilizing a viscous member and compression springs to stabilize the gap thickness and prevent rotational forces, allowing for stable and consistent damper force generation without increasing the printer's size.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a shutter member with rotating and sliding mechanisms is used to restrict printing sheet movement, then paper jams are prevented, but the printer size increases due to additional space requirements for these mechanisms

Engineering Contradiction:

Improvepaper jam preventionVSAvoidprinter size

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

The patent extracts the essential function of the shutter member (restricting printing sheet movement) and implements it through a simpler restricting member with restricting surface that rotates about a shaft portion, eliminating the need for complex sliding mechanisms while maintaining paper jam prevention capability

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of using a sliding mechanism to move the shutter member, the patent inverts the approach by using a rotating mechanism about a shaft portion, which achieves the same restriction function with simpler mechanics and reduced space requirements

Inventive Principle:

Principle #13The other way round (Inversion)

2Reliability

If a viscous member is used to generate damper force, then printing sheet movement is restricted, but variations in damper force occur due to changes in gap thickness during sliding

Engineering Contradiction:

Improvedamper force stabilityVSAvoidgap thickness consistency

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent replaces the sliding mechanical system with a rotating system about a shaft portion, which eliminates the gap thickness variation problem that occurs during sliding motion, thereby stabilizing the damper force generated by the viscous member

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent inverts the motion type from sliding to rotating, which fundamentally changes the mechanics of interaction between the viscous member and the restricting member, eliminating the harmful gap variations while maintaining the damper function

Inventive Principle:

Principle #13The other way round (Inversion)

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

The solution effectively restricts the movement of printing sheets, preventing paper jams while maintaining a compact printer design and stable damper force, ensuring reliable sheet alignment and transportation without the need for additional space for rotating mechanisms.

Implementation Method 1

a damper unit configured to rotate the restricting member from a restricting position for restricting the movement with respect to the object to a releasing position for releasing the restriction of the movement with respect to the object with a time lag

Methodology Applied

Scientific EffectViscous damping: Viscous Damping

Implementation Method 2

a first urging means configured to apply an urging force which causes the second member to slide from the first position to the second position

Methodology Applied

Scientific EffectElastic potential energy: Spring

Data Source

PatentUS8720883B2Recording apparatus

Publication Date: 2014.05.13 SEIKO EPSON CORP

AI summary

There is provided a recording apparatus including: a first member having a first sliding surface formed into a comb shape along the direction of movement of an object; a second member having a second sliding surface formed into a comb shape opposing the first sliding surface of the first member with the intermediary of a viscous member, the second member sliding between a first position which causes a restricting member to be positioned at a restricting position and a second position which causes the restricting member to be positioned at the releasing position in a state of engaging the restricting member; and a urging device configured to apply an urging force which causes the second member to slide from the first position to the second position, the urging device being arranged at least partly between tips and roots of teeth of the comb shape of the second sliding surface.