In this picture, Len and Rin represent Fuujin and Raijin respectively, as indicated by their costumes and the background text. Fuujin and Raijin are the gods of wind and thunder in Japanese mythology.

What is that coiled rope called? And that symbol with the three yangs?

I'm not sure what the coiled rope would be called in this context, in sumo it would be simply tsuna (rope). Both have their origins in the Shinto shimenawa that encloses holy sites.

The individual comma-like symbols are called tomoe; three tomoe in this specific organization is called mitsudomoe (three-tomoe). This mitsudomoe shape is commonly seen on drums and logos.