Structural Design and Performance Testing of Flexible Fabric Keyboard Switch
Flexible fabric keyboard is a field of smart textile. It can overcome traditional horniness keyboard can’t be foldable and washing. Because conventional keyboard’s switch is matrix circuit, two conductive layers are not touchable due to action of a middle insulating layer in relaxing. When the key is pressed, two conductive layers contact and form electric current. In this laboratory study there are two kinds of methods adopted, for example, Three-layer Fabric Weaved Separately (TFWS) and Three-layer Fabric Shaped Once(TFSO). They were significantly different in weaving methods, fabric structure and weaving efficiency. Three species were designed for every method. Although Connection Ratio (CR) of 6×6 and 8×8 in TFWS was 100%, TFWS took many repeating and complex processes. Much time and labor were seriously spent so that weaving efficiency was consumedly reduced. However, if making use of Three-layer Fabric Shaped Once(TFSO) which adopted three dimensional weaving method, only one procedure was required for fabric keyboard matrix circuit. The three dimensional weaving fabric consisted of support part and orifice part. When pressed in the key position, the top and down layer of the orifice part can contact with each other. Then the circuit can connect. When the applied force was released, the top and down layer can return to primary position due to the action of the support part. TFSO didn’t require many repetitive and complex courses. Therefore the weaving efficiency can be greatly increased. To be more importantly, CR of 16 wefts in TFSO was comparatively not bad among in three species of TFSO. When considering all six species for two methods together, 16 wefts in TFSO appears to provide the most suitable fabric for flexible fabric keyboard matrix circuit as a result of shaping once, high weaving efficiency and 100% CR. These findings may assist in recommendations regarding the further development of flexible fabric keyboard.
Yansheng Yin and Xin Wang
M. L. Zhang and R. Wang, "Structural Design and Performance Testing of Flexible Fabric Keyboard Switch", Advanced Materials Research, Vols. 79-82, pp. 1133-1136, 2009