shades vs winkers

shades

noun
  • Sunglasses. 

winkers

noun
  • blocked leather eye shields attached to a (usually) harness bridle for horses, to prevent them from seeing backwards, and partially sideways; blinders in (USA). 

  • a fleece cover wrapped around the cheek strap of a racing bridle to limit the rear vision of racehorses. 

How often have the words shades and winkers occurred in a corpus of books? (source: Google Ngram Viewer )