This name change occurred with a Buddhist monk.

Konoe Gyōki (1844-1872)

He was the son of Konoe Tadahiro, who would become a Buddhist monk in Senju-ji.

Tokiwai Gyōki (1872-1919)

Tokiwai (常磐井): (Japanese) time rock well

This may have been the name of a well that may have been nearby Senju-ji.

Gyoki would adopt his nephew Gyōyū, who would pass down the Tokiwai name.

Sources