| 摘要 |
1,172,766. Marine variable pitch propeller propulsion. SOC. FINANCIERE ET INDUSTRIELLE DES ATELIERS ET CHANTIERS DE BRETAGNE. 20 April, 1967 [7 June, 1966], No. 18269/67. Heading B7V. Overloading of an engine driving a ships variable (reversible) pitch propeller is prevented by a cam A connected to a controller or the engine fuel pump actuating a contactor 1 which de-energizes a solenoid operated valve E1, thereby stopping flow to and from the hydraulic ram V of the pitch changing mechanism, thus arresting change of pitch, further movement of the cam A resulting in further overload actuating a second contactor 2 which causes energization of the valve E1 resulting in supply to the hydraulic ram V in a direction to bring about a change of pitch in the reverse direction, i.e. if blade pitch is being increased actuation of contactor 1 arrests the increase and subsequent actuation of contactor 2 will then reduce the pitch. Hydraulic supply is through a valve E2 which is closed on operation of the contactor 1 so that the supply is through a restricted by-pass RD, the ram V thus operating slowly in the overload range. Reversers I1-I4, normally open when the ram V is in the zero pitch position, are closed one way or the other by a cam B whose movement corresponds to the movement of the ram V when the latter is in a position corresponding to ahead or astern pitch. |
