Abstract: A combined motor and transmission assembly in which a singular, tubular housing contains the motor and a planetary transmission. This tubular housing has the ring gear for the planetary transmission gear set formed integrally within its internal walls and also directly supports on its external wall a member driven by the planetary transmission.

Abstract: A roller skate arrangement, which comprises a rigid sole portion (12) to which there is secured on the top side of a shoe upper portion (11) and on the under side a forward and rear wheel pair or wheel bogies (23a, 26a). The wheels (23a, 26a) of each wheel pair can be adjusted to different distances from the sole portion (12) in order to permit oblique positioning of the sole portion (12) sideways relative to the road surface. The wheels (23a, 26a) of the rear wheel pair are pivotable about a first pivotal axis (17a) at right angles to the main plane of the sole portion (12), while the wheels of the forward wheel pair are pivotable about a second pivotal axis at right angles to the main plane of the sole portion.