Design and Experimentation of Automatic Tidying and Sorting Mechanism for Blood Collection Needles in Stacking State

摘要

Disposable blood collection needles become severely intertwined and hooked during stacking, and thus individually feeding disposable blood collection needles during mechanical packaging is di cult. Based on the physical characteristics of the blood collection needles during the stacking state, this study designed an automatic tidying and sorting mechanism by combining compound vibration, sorting, and conveying. During the feeding process, the compound vibration-type material-tidying mechanism tidies 20-30 blood collection needles first; then, the material sorting and conveying mechanism transports the tidied blood collection needles individually. The orthogonal testing of the automatic material tidying process shows that various experimental factors are ranked by the significance level of the e ect on the tidying process and the significance ranking is as follows: vertical vibration frequency ＞ horizontal amplitude ＞ vertical amplitude ＞ horizontal vibration frequency. Experiments were performed after analyzing the optimal combination. The results demonstrate that when the horizontal vibration frequency is 1.7 Hz, the horizontal amplitude is 150 mm, vertical vibration frequency is 1.3 Hz, vertical amplitude is 30 mm, and material length after tidying is 265 mm. The automatic sorting and conveying experiment shows the e ect of various experimental factors on the feed rate of the material, where the significance level of the e ect is ranked as follows: vibration frequency ＞ material quantity ＞ channel dip angle. The experimental results show that when the number of materials is 25, the channel dip angle is 12°, and vibration frequency is 52.5 Hz. The material delivery e ciency reaches 0.51 s/root, meeting the requirement of five channels for 80000 root/day feeding e ciency. The study can provide reference for the realization of automatic feeding of large aspect ratio flexible materials in similar stacking state.