A one way braking device has a first sealed chamber filled with a viscous fluid, a braking rotor being rotably supported within the chamber, a housing or the braking rotor, respectively, coacting with a pinion which in turn cooperates with a tooth rod or a gear or the like. The first housing is floatingly supported in a second chamber of a second housing. The circumference of the first housing and a locking portion of the wall of the second chamber are formed such that a positive interengagement between the first and second housings takes place if by a linear first force component the first housing and the locking portion are moved against each other. A free running between the first and second housings is effected when a second force component opposite to the first component effects between the first and second housings.