3648617 is referenced by 21 patents and cites 9 patents.

Apparatus for use with a vehicle which runs along a track to increase the traction of the drive wheels so they do not slip when starting or climbing hills. One traction increasing apparatus includes an extra track member for increasing the distance between upper and lower track surfaces that support the drive wheels and lower wheels, respectively, of the vehicle.

Title
Resilient gripping railway traction system
Application Number
04/848,884
Publication Number
3648617
Application Date
August 11, 1969
Publication Date
March 14, 1972
Inventor
Varney Justin A
Dashew Stanley A
Metzner Robert
Assignee
Security Pacific National Bank
IPC
B61b 13/04
B61b 13/02
B61b 03/02
B61C 15/02
B61C 15/00
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