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.

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