Reduction gear for turbomachine equipped with an electric generator

A mechanical reduction gear for a turbomachine, in particular

• for an aircraft, comprising:
• a sun gear equipped with external teeth, having a central axis forming a main axis of the mechanical reduction gear,
• a ring gear equipped with internal teeth, coaxial with the sun gear, planet gears, simultaneously meshed with the sun gear and the ring gear,
• a planet carrier, carrying spindles around which the planet gears are mounted in rotation, and
• at least one electric generator,
• wherein the electric generator comprises a first set of electromagnetic elements, disposed on a forward frontal face of a first planet gear, and a second set of electromagnetic elements disposed on a frontal surface of the front plate of the planet carrier, said frontal surface of the front plate of the planet carrier extending facing the forward frontal face of the sun gear so that the first set of electromagnetic elements and the second set of electromagnetic elements are disposed facing one another,
• wherein one among the first and second set of electromagnetic elements is a first set of coils, each coil of this first set of coils being wound around a direction parallel to the main axis,
• wherein the other among the first and second set of electromagnetic elements is a first set of magnets each of the poles of which is oriented in a direction parallel to the main axis so as to induce a current in the first set of coils when it is driven with a relative movement with respect to the first set of coils,
• wherein the electric generator comprises a third set of electromagnetic elements, disposed on a rear frontal face of the first planet gear, and a fourth set of electromagnetic elements disposed on a frontal surface of the rear plate of the planet carrier, said frontal surface of the rear plate extending facing the rear frontal face of the first planet gear,
• wherein one among the third and fourth set of electromagnetic elements is a second set of coils, each coil of this second set of coils being wound around a direction parallel to the main axis,
• wherein the other among the third and fourth set of electromagnetic elements is a second set of magnets each oriented in a direction parallel to the main axis so as to induce a current in the second set of coils when it is driven with a relative movement with respect to the second set of coils,
• wherein at least one set of magnets comprises a ring of several magnets, regularly spaced along the same circle centered on the axis of rotation of the planet gear, all oriented axially while alternating the direction of their North poles,
• wherein at least one set of coils comprises a ring of several coils, regularly spaced along the same circle centered on the axis of rotation of the planet gear, all wound around an axial direction, and
• wherein at least one set of coils comprises three coil assemblies, the coils of one given assembly being connected electrically to one another within the same circuit.

A mechanical reduction gear for a turbomachine, in particular for an aircraft, comprising:

• a sun gear equipped with external teeth, having a central axis forming a main axis of the mechanical reduction gear,
• a ring gear equipped with internal teeth, coaxial with the sun gear, planet gears, simultaneously meshed with the sun gear and the ring gear,
• a planet carrier, carrying spindles around which the planet gears are mounted in rotation, and
• at least one electric generator,
• wherein the electric generator comprises a first set of electromagnetic elements, disposed on a forward frontal face of a first planet gear, and a second set of electromagnetic elements disposed on a frontal surface of the front plate of the planet carrier, said frontal surface of the front plate of the planet carrier extending facing the forward frontal face of the sun gear so that the first set of electromagnetic elements and the second set of electromagnetic elements are disposed facing one another,
• wherein one among the first and second set of electromagnetic elements is a first set of coils, each coil of this first set of coils being wound around a direction parallel to the main axis,
• wherein the other among the first and second set of electromagnetic elements is a first set of magnets each of the poles of which is oriented in a direction parallel to the main axis so as to induce a current in the first set of coils when it is driven with a relative movement with respect to the first set of coils,
• wherein the electric generator comprises a third set of electromagnetic elements, disposed on a rear frontal face of the first planet gear, and a fourth set of electromagnetic elements disposed on a frontal surface of the rear plate of the planet carrier, said frontal surface of the rear plate extending facing the rear frontal face of the first planet gear,
• wherein one among the third and fourth set of electromagnetic elements is a second set of coils, each coil of this second set of coils being wound around a direction parallel to the main axis,
• wherein the other among the third and fourth set of electromagnetic elements is a second set of magnets each oriented in a direction parallel to the main axis so as to induce a current in the second set of coils when it is driven with a relative movement with respect to the second set of coils, and
• wherein the distance between the plane of at least one set of magnets and the plane of the facing set of coils is between 1 and 3 mm.