Generator having a disconnect mechanism
A generator for comprising a rotor, an inner shaft, an outer shaft, and an actuation means. The inner shaft is at least partially disposed inside the outer shaft. The inner shaft is coupled to the outer shaft by means of a translatable drive connection. The actuation means is configured to actuate the second shaft towards a retracted position. The translatable drive connection is configured to allow a transfer of torque between the first and second shafts, and enables movement of the second shaft, relative to the first shaft, along its axis of rotation from an extended position to a retracted position, such that an input portion of the second shaft can be at least partially retracted in a retraction direction towards the rotor upon activation of the actuation mechanism. A disconnect mechanism disposed on the second shaft can therefore be disconnected upon retraction of the second shaft.
1. A generator arranged to be mounted to an aircraft engine, comprising:
a rotor;
a first shaft to which the rotor is mounted so as to transfer a torque to or from the rotor;
a second shaft, at least partially disposed inside the first shaft, and coupled to the first shaft by means of a translatable drive connection, wherein the translatable drive connection is configured to allow a transfer of torque between the first and second shafts, and to enable movement of the second shaft along its axis of rotation, relative to the first shaft, from an extended position to a retracted position;
a first part of a disconnect mechanism for connection to a drive source, the first part of the disconnect mechanism comprising a tapered protrusion, configured to be received in a recess of a corresponding second part of the disconnect mechanism provided on a drive source for driving the generator; and
an actuation means, configured to actuate the second shaft towards the retracted position;
such that an input portion of the second shaft can be at least partially retracted towards the rotor upon activation of the actuation means.
2. A generator according to claim 1 , the first part of the disconnect mechanism being provided at the input portion of the second shaft.
3. A generator according to claim 2 , wherein the generator comprises a housing and the first part of the disconnect mechanism is arranged outside of the housing.
4. A generator according to claim 1 , comprising a biasing means configured to bias the second shaft towards the extended position.
5. A generator according to claim 4 , wherein the biasing means is arranged between the first shaft and the second shaft, to bias the second shaft towards the extended position.
6. A generator according to claim 1 , wherein the second shaft has an input end at the input portion, and a distal end, and the actuation means is arranged toward the distal end of the second shaft.
7. A generator according to claim 1 , wherein the translatable drive connection comprises one or more splines on each of the first and second shafts.
8. A generator according to claim 7 , wherein the one or more splines of the second shaft and the one or more splines of the first shaft each extend towards a distal end of the second shaft, the one or more splines of the second shaft extending towards the distal end of the second shaft further than the one or more splines of the first shaft.
9. A generator according to claim 1 , wherein the actuation means comprises one or more of: a rotatable link, a pivoted lever, a cam mechanism, a hydraulic mechanism, a pneumatic mechanism, a worm gear, a spring and release mechanism.
10. A generator according to claim 1 , wherein the second shaft comprises a lateral extension, the lateral extension being configured such that exertion of a force in the retraction direction on the lateral extension by the actuation means can axially displace the second shaft towards the retracted position.
11. A generator according to claim 10 , wherein the lateral extension comprises a material having a lower coefficient of friction than a material of the second shaft.
12. An aircraft engine assembly comprising:
a generator according to claim 1 ;
the input portion of the second shaft comprising a first part of a disconnect mechanism;
an output shaft of an engine or gearbox configured to drive the generator, the output shaft comprising a second part of the disconnect mechanism,
wherein when the actuation means is actuated, the first part and the second part of the disconnect mechanism are disconnected from each other, such that no torque from the output shaft can be transferred to the second shaft and vice versa.
13. An aircraft engine assembly according to claim 12 , wherein when the disconnect mechanism is in a disconnected configuration, no drive torque is transferred from the output shaft to any component of the generator.