Thermal Printer Foaming Layer for Tactile Graphics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing apparatuses for forming Braille and tactile graphics are large, expensive, and limited in expressing continuous straight lines or curved lines, making them unsuitable for personal use by visually impaired individuals who increasingly use personal computers.
Innovation Solution
A small-sized, low-noise, and inexpensive image formation apparatus using a thermal head that applies heat to a foaming layer on a printing medium from the lower surface, eliminating the need for a platen roller and allowing for the formation of arbitrary continuous straight lines or curved lines by using a convexly shaped conveyance guide and tension roller to maintain contact with the thermal head.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a platen roller with recessed grooves is used to push the printing medium against the thermal head, then the printing medium can be contacted with the thermal head, but the shape of the recess or line restricts the portion where a projection can be formed by expansion, making it impossible to draw continuous straight lines or curved lines
Solution Approach 1:
The invention extracts and removes the platen roller component from the thermal printing apparatus. By eliminating the platen roller with its restrictive grooves, the patent enables unrestricted expansion of the printing medium in any direction, allowing formation of arbitrary continuous straight lines, curved lines, and stereoscopic shapes without the geometric constraints imposed by fixed groove patterns.
Solution Approach 2:
Instead of using a platen roller to push the printing medium from above against the thermal head, the invention inverts the approach by using a tension roller to pull the printing medium from below, maintaining contact through tension rather than compression. This inversion removes the geometric constraints of traditional platen designs.
2Productivity
If heat is applied to the entire surface of the printing medium by a stereoscopic formation machine, then a stereoscopic image can be formed, but a foaming phenomenon occurs in portions other than intended foaming portions, making minute images difficult to form
Solution Approach 1:
The invention applies local quality by enabling selective heating only at specific locations on the printing medium through the thermal head. The tension roller maintains uniform contact across the entire printing medium surface, but the thermal head activates only the necessary heating elements corresponding to the intended stereoscopic image pattern, thereby preventing unwanted foaming in non-target areas while maintaining precision for minute images.
Solution Approach 2:
The thermal head is segmented into multiple independently controllable heating elements arranged in a matrix. This segmentation allows selective activation of only the specific heating elements corresponding to the intended stereoscopic image regions, preventing foaming in unintended portions while maintaining the ability to form precise minute images.
3Productivity
If the surfacemost layer of a foaming portion receives highest heat, then the stereoscopic image is formed, but the surfacemost portion of foaming easily becomes fragile and is easily scraped off
Solution Approach 1:
The invention employs periodic or pulsed heating action through the thermal head, applying heat in controlled intervals rather than continuous high-temperature exposure. This periodic heating allows the foaming material to expand and form the stereoscopic image while preventing excessive heat accumulation that would cause the surfacemost layer to become overly fragile and prone to scraping off.
4Adaptability or versatility
If a mechanical Braille printer is used to form stereoscopic images, then Braille and tactile graphics can be printed, but the apparatus size is large and the operation noise is large
Solution Approach 1:
The invention replaces the complex mechanical printing system with a thermal printing system. Instead of using mechanical dots and projections that require large components and generate noise, the patent uses a thermal head that applies heat to foamable material, creating stereoscopic images through controlled expansion. This substitution dramatically reduces apparatus size and operational noise while maintaining the capability to form Braille and tactile graphics.
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
Enables the formation of stereoscopic images with arbitrary shapes and sizes, reducing noise and cost while preventing foaming issues that affect minute image formation, making it suitable for personal use by visually impaired individuals.
Implementation Method 1
a thermal head which applies heat to a foaming layer on a printing medium from the lower surface of the medium
Implementation Method 2
a printing medium having an upper surface evenly coated with foaming capsules which foam when heated
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A thermal printer (100) according to this embodiment forms a stereoscopic image by applying heat to a printing medium (30) having a surface evenly coated with foaming capsules which foam when heated. More specifically, the thermal printer (100) includes a conveyance guide (40) which is formed into a convex shape whose apex is an image formation position where heat is applied to the printing medium (30), and regulates the position of the conveyed printing medium, and a thermal head assembly (11) which is installed such that a thermal head distal end portion (11c) contacts with the printing medium conveyed by the conveyance roller (22) from below the image formation position, and forms a stereoscopic image by applying heat to the printing medium (30).