Usually it requires to separate the warp yarn according the design if we want to weave a certain complicated pattern, it is too complicated to achieve by a normal weaving machine but can be easily done on a jacquard machine because of the jacquard shedding mechanism it equipped with. Jacquard shedding is a mechanism of jacquard machine that provides shedding method for enabling each warp yarn to rise and fall independently and being used to weave complex and large patterned fabrics such as portraits and landscapes designs.
Various types of jacquard shedding mechanisms are composed of 3 mechanisms: transmission mechanism, heald lifting mechanism, pattern control mechanism.
The production of jacquard fabrics has gone through a long process from manual to mechanical jacquard machine to today's electronic jacquard machine.
Electronic Jacquard Machine
1. Development of Electronic Machine
The research on electronic jacquard shedding mechanism internationally started at the end of World War II and made significant progress in the later 70 years with the help of application and development of large-scale integrated circuits and electronic computers. In 1983, the first electronic jacquard machine was exhibited as a sample machine at the Milan Textile Machinery Exhibition, many jacquard machine manufacturers have added it in their manufacturing plans since then. It shows that the development tendency of textile machinery have became brighter and brighter from 1980s.
2. Main Components
Compared with other mechanical jacquard machines, electronic jacquard machine has creative changes in pattern control. Although different electronic jacquard machines have different structures, most of them are all consist of 2 parts: electronic program control device, which can send out heald lifting information correctly and commonly with the functions of typing, displaying and printing and conversion device of electrical signal and mechanical quantity, which generally made of electromagnets, that is to convert the heald lifting information that sent by the electronic program control device into mechanical displacement for realizing mechanical control.
3. Control Principle
Electronic jacquard shedding integrates modern microelectronic technology and electromagnetic and photoelectric technology. With the cooperation of textile CAD system and new mechanical mechanism, it achieved the high-speed non-pattern jacquard, which greatly improved the production efficiency and product quality. The electronic jacquard control part takes a general-purpose microcomputer or industrial control computer as the main control body, uses data sources in the form of disk files and network files to adapt to the requirements of different weaving environments, develops corresponding interface circuits to read jacquard information and generate timing signals, and sends the jacquard information to the jacquard tap to implement jacquard control after drove it.
Jacquard fabrics can be divided into jacquard and mini jacquard according to the jacquard machine used. They are different in the production process and different in the pattern on fabric surface. Jacquard commonly includes flower, dragons and phoenixes, animals, landscapes, people, etc. 1-4 flower in same pattern across the entire width of the jacquard. The number of warp loops varies from a few hundred to over a thousand used during producing process. The patterns are usually large and delicate with distinct color layers and a strong sense of three-dimensionality while some small patterns are mostly dot or small geometric patterns, which are woven on 16-24 page dobby looms. These are all relatively simple patterns due to the limitation of the number of heald frame pages used.
The mini jacquard fabric are basically woven by dobby looms. It achieves to form various patterns on the surface of the fabric through the variation of two or more fabric tissues. For example, various small patterns in the same or different colors as the ground texture are arranged on a plain or twill ground. The mini jacquard is an organization with relatively concentrated points or warp and weft floating loops. Which usually includes the linear patterns, striped patterns, scattered patterns, etc.