Temperature Characteristic Research And System Test Of Electromagnetic Needle Separator

With the rapid development of knitting technology,people’s demand for knitted clothes is increasing.As a key part in the jacquard system of circular weft machine,the electronic needle selector determines the quality of knitted clothes to a large extent.In the actual production,it is found that the electromagnetic needle separator in a long time after continuous work,the large amount of heat generated by it can not be fully distributed in time,will have a certain adverse impact on the needle selection performance of the needle selector,so this paper aimed at the electromagnetic needle separator heat on the performance of the problem launched a study.Firstly,the types of electronic needle separator,the physical structure and working principle of the electromagnetic needle separator are introduced,and the basic theory of the electromagnetic force and heat transfer in the electromagnetic needle separator is expounded.Secondly,the electromagnetic needle separator is analyzed by the COMSO L simulation software.The key structural parameters of the electromagnetic needle separator,the size and location of the heat sink,material properties and external cooling conditions were adjusted respectively.The temperature of the whole electromagnetic needle separator was analyzed,and the temperature comparison diagram under different parameters was obtained.It was concluded that the temperature could drop about 4.51 ℃under the conditions of 18 mm electromagnet gap parameters.Then,the experimental data were compared to verify the reliability of the simulation model and prove the feasibility of optimizing the heat dissipation performance of the electromagnetic needle separator.Thirdly,Based on COMSOL simulation software,the electromagnetic thermal coupling analysis of electromagnetic needle separator was carried out.Because the electromagnetic force usually occurs on the time scale of a few milliseconds or even a few nanoseconds,while the temperature change of the ther mo physical field usually takes a few minutes or longer,based on the problem that the electromagnetic force and the thermo physical field have a large difference in time base,an innovative method of separating two-way coupling is proposed to solve the problem of inconsistent time step of electromagnetic field and thermo physical field simulation.The key parameters of the electromagnet were changed respectively,such as pulse voltage and pulse width,coil turns and air gap size,and the method of two-way coupling was used to separate the electromagnet temperature analysis and electromagnetic force analysis.By comparing the temperature curve and the electromagnetic force curve under different parameter conditions,it is concluded that when Al2O3(alumina ceramic material)is used as the electromagnet plastic skeleton,the temperature can drop about 1.88 ℃,and the electromagnetic force is also increased.Finally,a temperature test system of electromagnetic needle separator based on STM32F103C8T6 chip is designed to test and verify the temperature of electromagnetic needle separator under different parameter conditions.The simulation part of this paper has carried out the whole experiment verification.In this paper,COMSOL simulation software was used to conduct multi-physical field simulation of the electromagnetic needle separator,and the data of thermodynamics and electromagnetic force were analyzed and compared.Better heat dissipation conditions were obtained.The heat dissipation performance was impr oved while the electromagnetic force was also increased,which optimized the overall performance of the electromagnetic needle separator to a certain extent.