(2) Patent number of China utility model: ZL201020521271.9.
(3) Patent number of China utility model: ZL20 102052 1365.6.
(4) Patent number of China utility model: ZL20 102052 1379.8.
(5) China design patent number: ZL200930204373.0.
(6) China invention patent application number: 200910011303.2 (published).