Beijing, Dec. 3 -- Dongguan Gold Dragon Jewelry has filed a patent application for Cleaning Equipment for Jewelry. This invention was developed by Shao Jinxing, Liu Yuchen, Cao Xiaoyong, Wang Xinlei, Bai Zhihui, Li Wanfu, Chen Xuliang, Yin Zihua, He Wenbin, Fang Jilie, Wang Jiahui, Feng Kaihui and Huang Jiaqi. The patent appl..