Dispatching Cars on One-Track Lines 



A new signaling system by which one 

 man controls any number of cars 



ANEW signaling system for control- 

 ling interurban cars on one-track 

 trolley lines consists of an indicating 

 instrument at the dispatcher's office which 

 constantly records the progressive positions 

 of every car in service. This record is 

 made electrically by 

 a number of third 

 rails which are 

 strung along the 

 tracks and at the 

 sidings. 



When the cars 

 pass over one of the 

 third rails, a shoe 

 makes contact with 

 the rail, and two 

 electric circuits are 

 controlled. One cir- 

 cuit is in the car 

 itself and another 

 leads from the rail to 

 the dispatcher's in- 

 strument. The 

 closing of the latter 

 circuit operates an 



When the cars pass over the third rails two 

 electrical circuits are closed by a shoe, one 

 to the car and one to the dispatch office 



The indicating instrument in the dispatcher's 

 office records on a revolving sheet of paper 

 the progressive positions of each car in service 



At left : The signal lights in the motorman's 

 box of the car. A red light means to side- 

 track and a green light means "Proceed" 



electric pen and records the arrival of the 

 car on the paper of the instrument. The 

 dispatcher immediately moves a lever 

 which controls a return circuit to the third 

 rail. It is this which operates the signal- 

 circuit in the car. If the lever is moved one 

 way, a relay in the 

 car circuit connects 

 in a green light 

 placed above the 

 motorman's head, 

 and the motorman 

 proceeds on his way. 

 If the lever is moved 

 the opposite way, 

 a red light is shown, 

 which light warns 

 the motorman to 

 turn from his course 

 into the next siding. 

 Arriving at the third 

 rail at this siding, the 

 motorman waits for 

 the "all clear" signal 

 before going ahead 

 once more. 



Q1« 



