Abstract: A structural arrangement for detecting improper positioning between a hub. The structural arrangements utilize a bore which axially penetrates a stepped-down end portion of the shaft to receive a fastening means by which the hub may be secured to the shaft. A blocking bore extends radially through the stepped-down end portion of the shaft to communicate between the bore and the exterior of the shaft. A blocking member is received within the blocking bore and is movable radially therealong. A cam flange extends radially inwardly from the hub member and presents a blocking surface and a releasing surface on the radially inner extent thereof. The blocking surface is disposed in radial opposition to the blocking bore when the hub member is improperly positioned with respect to the shaft and the releasing surface is disposed in radial opposition to the blocking bore when the hub member is properly disposed with respect to the shaft.

Abstract: A hydrodynamic retarder has a centrally disposed chamber which is filled with hydraulic fluid and subjected to centrifugal forces. A valve mechanism, responsive to the operator, is opened by a control valve system when vehicle retarding action is requested to permit rapid filling of the retarder vane space from the centrally disposed chamber. The valve mechanism is also closed by the control valve system after a predetermined time. This accommodates fast filling of the retarder but does not permit air ingestion by the retarder. A passage, in the stationary housing portion of the retarder, is opened to the transmission pump circuit during retarding action to maintain the retarder pressure and fluid circulation for cooling. The central chamber has an air control valve to admit air to the chamber as the chamber empties of hydraulic fluid and to permit air exhaust therefrom when the chamber is refilled.