Abelman, Frayne & Schwab
Racetrack structure
 A racetrack structure includes several track sections, the track sections are engaged with each other by hinges, therefore the racetrack can be folded for storage. Each of the track sections of the racetrack structure has PC boards provided at two ends thereof, thereby forming an electrical loop by utilizing the PC boards electrically connected to each other by the hinges. By such arrangement, oxidization of the contact points is low. 
A
A63H
inventional
Yu-Bing
Chen