Here’s what Wikipedia has to say about Chester:

He was born Dec. 4, 1858 and died on July 5, 1937. His patent was for improved ear protectors and he manufactured them in Farmington, providing jobs for people in the  area for nearly 60 years.

Greenwood also patented a tea kettle, a variation of the steel-toothed rake, an advertising matchbox, and a machine used to produce wooden spools for wire and thread. He invented, but did not patent, an umbrella holder for mail carriers. 

In addition to being an inventor, Greenwood introduced one of the first telephone systems in Farmington. He was an accomplished machinist, an active member of the community, a business developer, a member of the Unitarian Church and a family man.