Common Handloom product
Chapter 4: Design and Development of Semi-Automatic Handloom
4.4 Total System design
151 two numbers of spiked rollers are used on each side (left and right), and as the cloth is taken up after weaving, the rollers roll to release the woven cloth maintaining uniform width. The selvedge obtained is also unbroken.
These temples can be adjusted for different widths of fabrics and are fitted to the loom with the help of a leaf spring set to provide spring-back action. In case the sley hits the temples, because of the spring back action, the temples will not damage the sley.
152 Colour: The color of the loom is selected for a neutral effect on the weaver's eye to provide a feeling of lightness on the loom. White and light grey are such colors used for fixed parts.
Yellow is used for moving parts, whereas bright orange is used for unsafe moving parts.
4.4.2 Operational aspects
In the loom designed, the shedding mechanism works independently. Handloom engages both the feet and facilitates mending the broken ends. Treadles are provided with two foot pedals (similar to the bicycle's).
The Burmese type of picking mechanism works in conjunction with the beat-up mechanism.
When the sley is taken to the extreme rear position, the shuttle is automatically propelled through the shed over the race board from one shuttle box to the other.
The synchronization required for this is that the weaver needs to form the shed by depressing the treadle as per the weaving pattern.
Similarly, the take-up works in conjunction with the sley's reciprocating motion. When the sley comes forward, the pawl of the take-up mechanism comes forward, sliding over the take- up guard, and in the reversing motion pulls forward the ratchet wheel as per the setting of the pick spacing. Also, the take-up mechanism is modified to house all the five gear wheels on only two shafts. The ratchet wheel, compounded change wheel, and take-up guard are freely mounted to the emery roller shaft. The change wheel drives the stud wheel, which is compounded with stud pinion and mounted freely on the stud pin. The stud pinion drives the emery roller wheel fixed onto the emery roller shaft. Adjustment of pick spacing is possible through the lever mounted on the stud pin and secured to it with nuts and bolts. It holds the take-up guard in a fixed position.
Let off mechanism works in conjunction with the take-up mechanism. The positive take-up of the woven materials generates tension on the warp sheet, and when this tension exceeds the resistance provided by the spring-loaded let-off mechanism, it let-off the required amount of warp.
The temple mechanism also works when the cloth is taken up. The rollers inside the temple mechanism allow the cloth to come forward for rolling onto the cloth roller.
Since loaded with spring, the oscillating backrest keeps the warp sheet in uniform tension. It only allows yielding the let-off mechanism after it has reached its limit and immediately takes up any slackness resulting from shed closing.
TH-3028_166105007
153 4.4.3 Manufacturability
The alpha model of the loom is designed to be manufactured out of 25mm X 25 mm square and 25mm X 50mm rectangular MS tubular structural elements with 2 mm thickness. It is done because laser cutting and sheet metal forming parts need to order in lots of 50 minimum to the vendor. Therefore, the alpha model manufactured with rectangular MS tubular structure checks all functional aspects. The beta model of the loom is designed to be manufactured from sheet metal simple formed parts which can be achieved by a CNC bending machine after cutting the blank in a laser cutting machine after a successful trial of the alpha model.
Parts are cut, welded, and drilled holes for fasteners. It needs only simple tool room machines like a power saw, arc welding machine, grinding machine, and drilling machine. For other parts, gears are to be procured ready-made from vendors, and other items can be produced using a lathe machine. A spray painting machine is used for painting the loom. For the sley made from wood, ordinary carpenter's tools are used.
Based on all these, it is evident that the loom can be easily manufactured in a moderately equipped workshop.
4.4.4 Serviceability
The loom virtually needs no regular servicing except lubrication of its very few moving parts like sley support, footstep bracket, crankshaft, take-up mechanism, let-off mechanism, and foot pedals for shedding. In case of wear and tear, all parts can be readily manufactured or repaired in any small workshop.
4.4.5 Cost
The handloom design uses minimum material; these materials are readily available and can be manufactured in the nearby available fabricator/workshop. The cost of the loom will be within the targeted range and hence can be marketed to the target group. Also, the cost can still be reduced if a larger batch is produced. A larger batch is indicated to be 50 looms per batch. This loom is designed to be easily manufactured and maintained at an affordable cost.
The cost of a traditional wooden handloom (38” width) shown in table 4.1 is 37500₹ as of FY 2020, out of which 25000₹ is for wood material and 12500₹ for purchasing essential accessories.
TH-3028_166105007
154 Table 4.1: Wood required for traditional handloom
SA Size Qty
Frame 4" x 3" x 6 ft 4 Frame 2" x 2" x 7 ft 2 Frame 2" x 3" x 6 ft 3 Frame 2" x 3" x 5 ft 2 Frame 2" x 3" x 3 ft 2 Frame 4" x 3" x 3 ft 2 Sley 2" x 3" x 7 ft 1 Sley 2" x 2" x 7 ft 1 Sley 2" x 2" x 5 ft 1 Sley 3" x 1" x 6 ft 1 Sley 4" x 1" x 6 ft 1 Naraj 5" x 1" x 4 ft 1 Warp beam 4" x 4" x 7 ft 1 Cloth beam 3" x 3" x 6 ft 1 Jacquard
guide 2" x 3" x 6 ft 2 Seat 2" x 1" x 8 ft 1 Seat 2" x 1" x 4 ft 2 Seat 2" x 1" x 4 ft 1 Stool 7" x 1" x 7 ft 1
The cost of a new Semi-automatic handloom (52” width) is 90000₹ as of FY 2020. This cost is high as it also includes warping drum and creel along with it.
The allowable cost of the machine and related equipment by the Government of India as per the technology up-gradation scheme has shown in Table 4.2.
TH-3028_166105007
155 Table 4.2: Allowable cost of the machine and related equipment by the Government of India