Abstract:In order to solve the problem that it is difficult to separate the shell and tea seed due to the irregular shell breaking after mechanical shell breaking of Camellia oleifera fruit, a shell breaking method of Camellia oleifera fruit based on conical needle is proposed. The conical needle acts on the top area of Camellia oleifera fruit shell. With the conical needle inserted into the top area of Camellia oleifera fruit, the Camellia oleifera fruit shell splits along the biological valve on the top of Camellia oleifera fruit, forming a crack, and the crack gradually increases (if the crack size reaches more than 5 mm, it is considered to be completely broken), and then the conical needle moves back to the original position to complete the shell breaking of Camellia oleifera fruit. Through the comparative analysis of pre-test, the conical angle of conical needle (30°, 45°, 60°), the depth of conical needle inserted into the shell (5,8,11 mm) and the storage days after picking (2,5,8 d) are selected as influencing factors to conduct single factor test. The results showed that the cracking force and cracking size of camellia fruit increased with the increase of cone angle and insertion depth. With the increase of storage time, the cracking force decreases and the crack size increases. The orthogonal test with three factors and three levels were carried out. The results showed that when the cone needle angle was 60°, the cone needle insertion depth was 11 mm and the storage time was 8 d, the average crack size was 5.4 mm and the average breaking force was 83.8 N.