| Computer flat knitting machine which involves many technical fields such as computer, machinery, electronics and so on, is a complex mechatronics product, it is very significant for knitting industry to improve its automation level and production efficiency. However, there is still a certain gap between domestic computer flat knitting machine. Therefore, the control system and automation of domestic device must be improved, so that the imported equipment would be replaced by home equipment. Such key technologies of computer flat knitting machines are studied in this thesis, and some achievements have made in the carriage rapid return, length detection and adaptive control of the yarn and dynamic functions. The main contents are as follows:1.Carriage rapid return. The information of carriage control is sent to servo driver one course advance before to make the carriage rapid smooth return, and the control system communicates through the CAN bus. And the Performing machines are optimized to reduce the carriage return distance.2.The yarn length control. Coding mask is used to indirectly detect the length of yarn, and the amount of the next line of yarn will be adjusted automatically by compare with the standard length. The deviation between the actual and standard amount of yarn will be controlled within 8%, so that the length of yam automatically control is achieved.3.Dynamic stitch function. The carriage is located in a precise position relative to the needle bed by three square waves which have a 120°phase difference among them. And the stepper motor drive frequency curve and the density drive of zero-clearance transmission structure are designed to achieve the dynamic function. When carriage speed is at 0.3m/s～ 1.0m/s and the maximum density is 0.6mm, the dynamic area of influence is less than one inch. |
