The Refinement of the Jacquard Machine
In fine silk weaving on Jacquard hand looms the limitations were that each harness thread from the mechanism on the top of the loom required a lead weight (lingoes) to keep the tension on the lift. This meant that the physical leg strength needed to press treadles open the weave shed was to ever increase with more and more complex harness layouts being desired. The dimensions of the machine itself began to fill the top of the loom frame with multiple sets of pattern cards for each cylinder used. With increased widths of cloths and complex designs a loom could have four machines to control the pattern and weaves.
Missed the first installment? then read ‘Jacquard’s Weaving Revolution’ or up next ‘From shuttle to rapier’
What was needed was the ability of original concept but a smaller machine in size. This led to “fine pitch” jacquards where 1200 hooks and needles took the space of 400 on earlier models. This was the refined Vincenzi system that furthered quest for improvement. At the same time the power-loom was taking the place of hand production. This machine worked on finer needles compacted together inside the mechanism. With this development came the need for speed.
Image: Example of the Vincenzi Card System
Single cylinder Jacquards relied on the turning of a square cylinder a quickly as possible, but in doing so would often tear the program cards with the violent movement. By creating double cylinder machines and feeding the pattern cards in alternately, loom speeds increased. To this add six sided cylinders to slow the turning of the programme cards and machines were now capable of over 100 weft insertions per minute.
Great machinists such as Devoge & Draycup strived to improve the machines ability but Verdol managed to dispense with the laced cards for programming and feed a continuous punched paper roll around a circular cylinder. This dramatic change speeded up the weaving process enormously and with electronic paper cutting the designs could easily be changed.
Image: Verdol Paper Roll Mechanism
Where would the development of Jacquard’s weaving machine lead to next? Check back soon for the next installment.