Inventor: Bobby Fischer
Invention: Fischer Clock
Inventor’s Location: Born in USA (now in Iceland)

Bobby Fischer (Robert James “Bobby” Fischer), the inventor of Fischer clock, died today. He was 65.
Not many people know that he invented the Fischer clock. He is more famous as the only American player to become the official world chess champion. He won the championship in 1972 by defeating Boris Spassky. He was well-known for his controversial remarks and actions during the last two decades.

Game clocks are used while playing chess tournaments to keep track of the total time taken by the players for their moves. In 1988, Fischer filed for U.S. Patent 4,884,255 for a new type of digital chess clock. Fischer’s digital clock gave each player a fixed period of time at the start of the game and then added a small amount after each move. For example, if the delay is five seconds and the player has ten minutes remaining on his clock, when his clock is activated, he now has ten minutes and five seconds remaining. Time can be accumulated, so if the player moves within the delay period, his remaining time actually increases. This made sure that the players would never be desperately short of time. Also, games could be completed more quickly, thus eliminating the need for adjourning matches.

Fischer’s invention had a a synthesized voice announcing how much time the players have, but this is not used in the Fischer clocks used for tournaments.

The patent application filed for the invention provides this summary:
“A game timing apparatus and method for simultaneously timing events for two players is disclosed. The method involves presetting a pair of clocks for respective initial time periods, starting one of the clocks to time a first player’s move, simultaneously stopping one clock and starting the other, and incrementing or decrementing each of the clocks by a time interval once for each move or a group of moves. The apparatus includes a pair of clock means, a pair of start switches for starting and stopping the clock means, and a compensation means for incrementing or decrementing each clock means by a time interval.”
You can see the application filed for the invention here: Fischer Clock Patent Application.
The patent for the invention expired in November 2001. But Fischer clock is still being used in many top chess tournaments.