by sccaflagger74
I posted this on the SEPTA forum because of their use of both trolleys and trolley buses (err, sometimes).
I thought of this question (again) while riding the 102 home from work on Monday. I noticed at Drexel Hill Jct a box at operator height with buttons marked Media and Sharon Hill. Presumably the operator presses this button to indicate which route he is taking thus changing the signal/switch or some such combination. This made me think back (via a roundabout thought process!) to trolley poles and how they negotiate diverging routes.
Obviously pantographs contact the bottom of the wire and thus don't have to really negotiate divergances. But how do trolley poles such as on the city trolleys and the trolley buses know which route to take? Does the turning of the vehicle "pull" the pole onto the correct wire?
Simple question, perhaps, but I've always wondered how it worked.
Thanks,
Bob
I thought of this question (again) while riding the 102 home from work on Monday. I noticed at Drexel Hill Jct a box at operator height with buttons marked Media and Sharon Hill. Presumably the operator presses this button to indicate which route he is taking thus changing the signal/switch or some such combination. This made me think back (via a roundabout thought process!) to trolley poles and how they negotiate diverging routes.
Obviously pantographs contact the bottom of the wire and thus don't have to really negotiate divergances. But how do trolley poles such as on the city trolleys and the trolley buses know which route to take? Does the turning of the vehicle "pull" the pole onto the correct wire?
Simple question, perhaps, but I've always wondered how it worked.
Thanks,
Bob