Hydraulically regulated electromagnetic actuator, and landing gear fitted with such an actuator for controlling same

1. An electromechanical actuator comprising:

an electric motor ( 11 ) for driving an output shaft ( 4 ) in rotation via a reduction gear ( 20 ),

passive regulation means ( 30 ) allowing for control of the speed of rotation of the output shaft, and

a braking member, arranged between an output of the reduction gear and the output shaft to be driven, said braking member being arranged to ensure two different braking levels depending on the direction of rotation of the shaft,

wherein the braking member is of hydraulic type and comprises means ( 33 ) for transferring fluid between a first chamber ( 34 ) and a second chamber ( 35 ), under the effect of the rotation of the output shaft through:

a first selective drawing member ( 41 ) which, depending on the direction of rotation of the actuator, opposes two distinct resistances to the transfer of the fluid from one chamber to the other chamber, and through;

a second selective drawing member which, depending on the direction of rotation of the actuator, opposes two distinct resistances to the transfer of the fluid from one chamber to the other chamber,

said first and second selective drawing members being disposed in series and each one of said first and second selective drawing members comprising a restrictor ( 42 ) in parallel with a non-return valve ( 43 ) forcing the fluid to pass through the restrictor ( 42 ) when the fluid is transferred from the first chamber ( 34 ) to the second chamber ( 35 ), but shunting the restrictor ( 42 ) when the fluid is transferred from the second chamber ( 35 ) to the first chamber ( 34 ).

2. The actuator according to claim 1 , in which the braking member comprises a cylindrical casing ( 31 ) in which a fixed segment ( 38 ) and a rotating paddle ( 33 ) extend to define the two chambers ( 34 , 35 ) and provoke the transfer of fluid from one chamber to the other chamber during rotation of said rotating paddle ( 33 ).

3. The actuator according to claim 1 , in which the fluid is transferred from one chamber to the other chamber by passing through an accumulator ( 36 ).

4. The actuator according to claim 1 , in which the fluid is transferred from one chamber to the other chamber by passing through an accumulator ( 36 ), and in which the first chamber communicates with the accumulator ( 36 ) via a fluidic branch comprising said first and second selective drawing members;

said restrictor ( 42 ) and said non-return valve ( 43 ) of the first drawing member being disposed so as to force the fluid to pass through the restrictor of the first drawing member when the fluid passes from the first chamber ( 34 ) to the accumulator ( 36 ), and so as to shunt the restrictor ( 42 ) when the fluid passes from the accumulator ( 36 ) to the first chamber ( 34 ); and

said restrictor and said non-return valve ( 43 ) of the second drawing member being disposed so as to force the fluid to pass through the restrictor of the second drawing member when the fluid passes from the first chamber ( 34 ) to the accumulator ( 36 ), and so as to shunt the restrictor ( 42 ) of the second drawing member when the fluid passes from the accumulator ( 36 ) to the first chamber ( 34 ).

5. Aircraft landing gear comprising:

a caisson ( 51 ) articulated on a structure of aircraft, the aircraft landing gear being movable between a retracted position and a deployed position by pivoting the caisson ( 51 ) relative to the structure of the aircraft;

an actuator for maneuvering between the retracted position and the deployed position, the actuator comprising an electric motor ( 11 ) for driving an output shaft ( 4 ) in rotation via a reduction gear ( 20 ) and passive regulation means ( 30 ) allowing for control of the speed of rotation of the output shaft, and comprising a braking member, arranged between an output of the reduction gear and the output shaft to be driven, said braking member being arranged to ensure two different braking levels depending on the direction of rotation of the shaft, wherein the braking member is of hydraulic type and comprises means ( 33 ) for transferring fluid between a first chamber ( 34 ) and a second chamber ( 35 ), under the effect of the rotation of the output shaft through a first selective drawing member ( 41 ) which, depending on the direction of rotation of the actuator, opposes two distinct resistances to the transfer of the fluid from one chamber to the other chamber, said first selective drawing member ( 41 ) comprising a restrictor ( 42 ) in parallel with a non-return valve ( 43 ) forcing the fluid to pass through the restrictor ( 42 ) when the fluid is transferred from the first chamber ( 34 ) to the second chamber ( 35 ), but shunting the restrictor ( 42 ) when the fluid is transferred from the second chamber ( 35 ) to the first chamber ( 34 ),

wherein the actuator is arranged so that, when its output shaft is driven by the lowering of the landing gear to the deployed position, the braking member exerts the greatest braking level.

6. The landing gear according to claim 5 , in which the output shaft of the actuator is coupled to a bracing element ( 52 ; 53 ) of the landing gear, said bracing element being articulated on the one hand on the structure of the aircraft and on the other hand on the caisson.

7. Aircraft landing gear comprising:

a caisson ( 51 ) articulated on a structure of aircraft, the aircraft landing gear being movable between a retracted position and a deployed position by pivoting the caisson ( 51 ) relative to the structure of the aircraft;

an actuator for maneuvering between the retracted position and the deployed position, the actuator comprising an electric motor ( 11 ) for driving an output shaft ( 4 ) in rotation via a reduction gear ( 20 ) and passive regulation means ( 30 ) allowing for control of the speed of rotation of the output shaft, and comprising a braking member, arranged between an output of the reduction gear and the output shaft to be driven, said braking member being arranged to ensure two different braking levels depending on the direction of rotation of the shaft, wherein the braking member is of hydraulic type and comprises means ( 33 ) for transferring fluid between a first chamber ( 34 ) and a second chamber ( 35 ), under the effect of the rotation of the output shaft through a first selective drawing member ( 41 ) and a second selective drawing member, said drawing members which, depending on the direction of rotation of the actuator, opposes two distinct resistances to the transfer of the fluid from one chamber to the other chamber;

said first selective drawing member ( 41 ) comprising a restrictor ( 42 ) of the first selective drawing member in parallel with a non-return valve ( 43 ) of the first selective drawing member forcing the fluid to pass through the restrictor ( 42 ) of the first selective drawing member when the fluid is transferred from the first chamber ( 34 ) to the second chamber ( 35 ), but shunting the restrictor ( 42 ) of the first selective drawing member when the fluid is transferred from the second chamber ( 35 ) to the first chamber ( 34 ); and

said second selective drawing member comprising a restrictor of the second selective drawing member in parallel with a non-return valve ( 43 ) of the second selective drawing member forcing the fluid to pass through the restrictor ( 42 ) of the second selective drawing member when the fluid is transferred from the first chamber ( 34 ) to the second chamber ( 35 ), but shunting the restrictor ( 42 ) of the second selective drawing member when the fluid is transferred from the second chamber ( 35 ) to the first chamber ( 34 ); and

wherein the actuator is arranged so that, when its output shaft is driven by the lowering of the landing gear to the deployed position, the braking member exerts the greatest braking level.