The sword is a niuweidao (牛尾刀, "Ox Tail Saber"), a single-edged broadsword used in Chinese martial arts, although the sword's blade has a greater resemblance to the Chinese Guan Dao, Korean Hyeopdo, or Russian Sovnya.
When Tao was overpowered by Goku, he brought out a capsule. He then tossed the capsule and the sword appeared. It was used for a limited time though as Goku dodged a few attacks from Tao's blade, with Upa throwing the Power Pole to Goku, which he used to break Tao's sword. After that, they went back to regular combat.