Circular manual device adapted to calculating the average speed obtained as a function of the time taken to cover a certain distance

摘要

Circular manual device adapted to calculating the average speed obtained as a function of the time taken to cover a certain distance. It consists of two concentric discs 1, 2, of different diameters, each supporting a circular logarithmic scale 5, 6 which scales face each other; one is in distance units and the other is in time units. Setting the two values to coincide using a tag 8 of the index 3 allows the corresponding speed to be read from the distance scale 5, facing the tag 7 situated on the time scale 6. The discs and the index are joined using an eyelet 4. Being simple and quick to use, the device according to the invention is in particular intended for calculating speeds for all timed movements. IMAGE