Printer Tension Bar Guide Groove for Independent Roll Diameter Control

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Solution Overview

Problem

Inkjet printers face usability issues due to restrictions in setting the maximum outer diameter of a medium before and after printing, as the outer diameter of one roll shape is limited by the other, affecting user convenience and tension application precision.

Innovation Solution

The printer design includes a tension applying mechanism with a guide groove for the tension bar, allowing it to move vertically and maintain consistent tension, and separate roll attaching portions for before and after printing, enabling independent setting of roll diameters without interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the media feeding means is disposed immediately on the back side of the supporting leg and the media winding means is disposed immediately on the front side, then the printer structure is compact, but the maximum outer diameter of the medium roll is restricted by interference between rolls

Engineering Contradiction:
Improveprinter structure compactnessVSAvoidmaximum outer diameter of medium roll
Core Design Contradiction:
Volume of moving objectVSAdaptability or versatility

Solution Approach 1:

The patent introduces a guide groove structure that guides the tension bar in the vertical direction, adding a vertical dimension to the tension application mechanism. This dimensional change allows the tension bar to move independently vertically while the rolls are arranged horizontally, resolving the spatial interference issue and enabling larger roll diameters without increasing horizontal footprint.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Device complexity

If the tension bar is rotatably attached to the distal end of the media arm which rotates about the basal end, then the tension applying mechanism is simple, but the tension consistency deteriorates when the media arm rotates

Engineering Contradiction:
Improvetension applying mechanism simplicityVSAvoidtension consistency
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent extracts the rotational movement function from the tension bar itself and separates it into two independent components: the media arm rotation and the guide groove constrained vertical movement. The guide groove structure constrains the tension bar to move only vertically, eliminating the rotational component that caused tension inconsistency while maintaining the simplicity of the mechanical linkage.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The guide groove acts as an intermediary constraint between the tension bar and the media arm. It mediates the motion by allowing vertical movement while preventing rotational movement, ensuring that the tension bar maintains consistent orientation and applies uniform tension to the medium throughout the printing process.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 design ensures appropriate tension can be applied to both pre- and post-printed rolls, enhancing user convenience and design flexibility by allowing larger roll diameters without compromising tension consistency.

Implementation Method 1

a frame, in which a guide groove having a slit shape for guiding the tension bar in the vertical direction is formed

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3552832B1printer
Publication Date: 2021.08.11 MIMAKI ENGINEERING CO LTD
  • EP3552832B1 patent drawingFigure 1
  • EP3552832B1 patent drawingFigure 2
  • EP3552832B1 patent drawingFigure 3

AI summary

A printer 1 includes a printer main body 3 that performs printing on a medium 2, a supporting frame 18 that supports the printer main body 3 from a lower side, a tension applying mechanism 5 including a tension bar 23 that comes into contact with the medium 2 before printing and applies a tension to the medium 2, and a roll attaching portion 8 and a roll attaching portion 9 to which the medium 2 before printing wound into a roll shape is attachable The roll attaching portion 8, the tension bar 23, and the roll attaching portion 9 are disposed on a back side of the supporting frame 18 and are disposed in such order from the supporting frame 18 side; and the medium after printing is wound into a roll shape on a front side of the supporting frame 18. The tension applying mechanism 5 includes a frame 24 having a guide groove 24a for guiding the tension bar 23 in a vertical direction.