How a Park-O-Meter Works - Historical Wonders!

Before the age of microchips, engineers developed ways to accomplish tasks such as setting a timer using physical mechanisms. One of my favorite clock mechanisms is found in the 1940/1950 Park-O-Meter, parking meters. This clever device uses both sides of a single spring to power a winding mechanism AND power the timer. It also has an ingenious physical mechanism for determining a penny from a nickel based on the size of the coin. In short, it is a wonderful example of one of the earliest devices that have now come to plague our downtown visits :)