Design and development of a foot pedal operated ‘Center Close Shed- Horizontal Lever Electronic Dobby’ for weaving all-over and brick motif fabrics

Abstract

The present research has addressed the limitations faced by woven fabric designers in developing a wide range of all-over and
intricate brick motif fabric samples by manipulating the drafting in healds and heald lifting plans. Multi-treadles with tumbler levers and mechanical vertical hook dobby are the only two shedding devices available to weave all-over and intricate brick motif fabrics. These traditional shedding devices have proven impractical due to the cumbersome operation of multi-treadles in proper sequence. In vertical hook dobby shedding, a larger number of pegged lattices is required to lift the healds. Hence, this research focuses on designing and developing a new ‘Center Close Shed – Horizontal Lever (CCS-HL) Electronic Dobby’ shedding device with ‘Horizontal Levers’ that can be used in place of treadles in the existing multi-treadle handloom to form a ‘Center Close Shed’ with tumbler lever reversing motion. The dobby is designed with two horizontal levers to lift or lower each heald. The selection of levers in the required sequence is done by the ‘Solenoid Electronic System’ instead of treadle operation in different sequences or huge pegged lattice selection. The electronic system is operated by inputting the digital lifting plan prepared from any open-source Paint software. This dobby can be used in the existing multi-heald handloom with a tumbler lever reversing motion by replacing the treadles. A diamond brick motif fabric sample is developed using the new dobby to operate eight healds. The possibilities of weaving different brick motif samples by keeping the same draft but changing the heald lifting plans are explored. A foot pedal is used to operate the dobby. Hence, the time required for sample development decreases from 25 % to 33 % compared to the multi treadle operation. Using this dobby, the designers could develop different all-over and brick motif fabrics by changing the lifting plan and setting the loom with a definite drafting order. Handloom, Textile, and Fashion Technology Institutes can use this dobby in Weaving and Fabric Analysis Laboratories to weave and learn the different woven fabric structures effectively. It is also handy for textile research centers and weaving mills to develop innovative, diversified fabric samples for R&D activities and get the sample approvals fast before going for bulk production.