Rotor for a hover-capable aircraft

Patent metadata

Field	Value
Publication number	US-12012204-B2
Application number	US-202017789871-A
Country	US
Kind code	B2
Filing date	Dec 28, 2020
Priority date	Dec 30, 2019
Publication date	Jun 18, 2024
Grant date	Jun 18, 2024

Abstract

A rotor for an aircraft is described having: a support angularly fixed with respect to an axis and housing a power source; a unit rotatable about axis and housing an electrical load of the resistive type; and a power supply system for the electrical load ( 21, 24 ) and comprising: a first transformer electrically interposed between the power source and the load; the first transformer comprises: a first winding arranged on the support and a second winding arranged on the unit, a stator carried by the support, rotationally fixed with respect to axis and to which the first winding is fixed; and a rotor operatively connected to the unit and to which the second winding is fixed; the power supply system comprises a capacitive circuit electrically connected to the first transformer, so as to reduce the reactive power absorbed by the rotary transformer.

First claim

The invention claimed is:

1. A rotor ( 3 , 4 ) for a hover-capable aircraft ( 1 ), comprising:
a support ( 9 ) angularly fixed with respect to an axis (B, C) and housing an electrical power source ( 20 );
a unit ( 11 , 12 ) rotatable with respect to said support ( 9 ) about said axis (B, C) and housing an electrical load ( 21 , 24 ) of the resistive type; and
a power supply system ( 19 , 19 ′, 19 ″, 19 ″′, 19 ″″, 19 ″″′, 19 ″″″, 19 ″″″′) adapted to electrically power said electrical load ( 21 , 24 ); said power supply system ( 19 , 19 ′, 19 ″, 19 ″′, 19 ″″, 19 ″″′, 19 ″″″, 19 ″″″′), in turn, comprising:
at least a first rotary transformer ( 22 ) electrically interposed between said power source ( 20 ) and said electrical load ( 21 , 24 ); said first rotary transformer ( 22 ), in turn, comprising:
a first winding ( 26 ) arranged on said support ( 9 ), electrically connected to said power source ( 20 ) and which can be electrically supplied with an alternating voltage at a frequency value;
a second winding ( 28 ) arranged on said unit ( 11 , 12 , 13 ), electromagnetically coupled to said first winding ( 26 ) and electrically connected to said electrical load ( 21 , 24 );
a stator ( 100 ) carried by said support ( 9 ), rotationally fixed with respect to said axis (B, C) and to which said first winding ( 26 ) is fixed; and
a rotor ( 101 ) operatively connected to said unit ( 11 , 12 ) and to which said second winding ( 28 ) is fixed;
said power supply system ( 19 , 19 ′, 19 ″, 19 ″′, 19 ″″, 19 ″″′, 19 ″″″, 19 ″″″′) comprising a capacitive circuit ( 50 ) electrically connected to said first rotary transformer ( 22 ), so as to reduce the reactive power absorbed by said first rotary transformer ( 22 ); characterized in that said stator ( 100 ) defines a seat ( 171 ) engaged by an appendage ( 140 ) of said rotor ( 101 ); said seat ( 171 ) being engaged with axial play by said appendage ( 140 ) when said rotor ( 101 ) is correctly positioned with respect to said stator ( 100 ); said seat ( 171 ) making axial contact with said appendage ( 140 ) when said stator ( 100 ) is positioned incorrectly in the axial direction.

2. The rotor according to claim 1 , characterized in that said capacitive circuit ( 50 ) is configured to reduce the overall reactance of said first rotary transformer ( 22 ) and the capacitive circuit ( 50 ) seen from said power source ( 20 ) at said frequency value.

3. The rotor according to claim 1 , characterized in that said capacitive circuit ( 50 ) comprises:
a first branch ( 51 ) electrically interposed between said power source ( 20 ) and said first winding ( 26 ) and electrically suppliable with an alternating voltage, and carried by said stator ( 100 ); and/or
at least a second branch ( 52 ) electrically interposed between said second winding ( 28 ) and said electrical load ( 21 , 24 ), and carried by said rotor ( 101 ).

4. The rotor according to claim 1 , characterized in that said seat ( 171 ) comprises an electrically insulating element ( 172 ) and an electrically conductive element ( 173 ) housed inside said electrically insulating element ( 172 ) and electrically connected to a second electrical circuit ( 174 );
said second electrical circuit ( 174 ) being, in use, electrically open when said appendage ( 140 ) is axially set apart from said seat ( 171 );
said second electrical circuit ( 174 ) being, in use, electrically closed when said appendage ( 140 ) is in contact with said seat ( 171 ).

5. The rotor ( 3 , 4 ) according to claim 1 , characterized in that said stator ( 100 ) comprises a first magnetic half-core ( 25 ) and at least a first slot ( 102 ) engaged by the first winding ( 26 );
said rotor ( 101 ) comprising a second magnetic half-core ( 27 ) and at least a second slot ( 103 ) engaged by said second winding ( 28 );
said first and second magnetic half-cores ( 25 , 27 ) being annularly shaped;
said first magnetic half-core ( 25 ) being housed inside said second magnetic half-core ( 27 );
at least one of said first and second magnetic half-cores ( 25 , 27 ) having a double-C section in a plane parallel to said axis (B, C).

6. The rotor ( 3 , 4 ) according to claim 1 , characterized in that said stator ( 100 ) comprises a first main body ( 119 ) housing said first winding ( 26 );
said rotor ( 101 ) comprising a second main body ( 130 ) housing said second winding ( 28 );
said first and second main bodies ( 119 , 130 ) being hollow and respectively closed on a first and a second side, opposite to each other;
said second main body ( 130 ) being partially housed inside said first main body ( 119 ).

7. The rotor according to claim 1 , characterized in that said first winding ( 26 ) is arranged radially internal with respect to said second winding ( 28 );
and/or characterized in that said power supply system ( 19 , 19 ′, 19 ″, 19 ″′, 19 ″″, 19 ″″′, 19 ″″″, 19 ″″″′) comprises support means ( 105 ) interposed between said stator ( 100 ) and said rotor ( 101 ).

8. The rotor according to claim 7 , characterized in that said support means ( 105 ) comprise a rolling-contact bearing ( 105 ) carried by the stator ( 100 );
said rolling-contact bearing ( 105 ) comprising:
a first ring ( 108 ) carried by said stator ( 100 );
a second ring ( 109 ) arranged with a radial clearance with respect to said rotor ( 101 ) when the rotor ( 101 ) is, in use, correctly positioned with respect to said stator ( 100 ); and
a plurality of rolling bodies ( 110 ) interposed between said first and second rings ( 108 , 109 );
said second ring ( 109 ) being stationary with respect to said axis (B, C) when said rotor ( 101 ) is correctly positioned and radially set apart from said second ring ( 109 );
said second ring ( 109 ) cooperating with said rotor ( 101 ) when the latter is incorrectly positioned with respect to said stator ( 100 );
said first ring ( 108 ) being electrically insulated from said stator ( 100 ) and being electrically connected to a first electrical circuit ( 113 );
said first electrical circuit ( 113 ) being, in use, electrically open when said stator ( 100 ) and said rotor ( 101 ) are radially set apart;
said first electrical circuit being, in use, electrically closed when said stator ( 100 ) and said rotor ( 101 ) are in contact.

9. The rotor according to claim 1 , characterized in that said capacitive circuit ( 50 ) comprises:
a first node ( 45 ) and a second node ( 44 ) that can be electrically supplied with an alternating voltage;
a first capacitor ( 47 b ) electrically connected between said first node ( 45 ) and a third node ( 46 ); and
a second capacitor ( 47 a ) electrically connected between said first node ( 45 ) and said second node ( 44 );
said first winding ( 26 ) being connected in series between said third node ( 46 ) and said second node ( 44 ); and/or
characterized in that said circuit ( 50 ) comprises a third capacitor ( 54 ) electrically interposed in series between said second winding ( 26 ) and said electrical load ( 21 , 24 ).

10. The rotor ( 3 , 4 ) according to claim 9 , characterized in that it comprises a plurality of blades ( 13 ) housing respective said electrical loads ( 21 , 24 );
said power supply system ( 19 ″) comprising, for at least said blade ( 13 ):
a first inverter ( 40 ) electrically connected to said power source ( 20 ) and to said first winding ( 26 ) of said first rotary transformer ( 22 ); said first inverter ( 40 ) comprising:
two fourth input nodes ( 41 , 42 ) that can be supplied with a first value of direct voltage (VIN) and two fifth output nodes ( 43 , 44 ) at which a second value of alternating voltage is made available; and
a first current sensor ( 201

Assignees

• Leonardo Spa
• Milano Politecnico

Inventors

• Bellussi Enrico
• Brunetti Massimo
• Facchini Giovanni
• Ostuni Nicola
• Castelli Dezza Francesco
• Mauri Marco
• Chatterton Steven
• Toscani Nicola

Classifications

• H01F21/04

  by relative movement of turns or parts of windings · CPC title

• F16C2326/43

  Aeroplanes; Helicopters · CPC title

• F16C19/06

  with a single row or balls · CPC title

• B64D45/00

  Aircraft indicators or protectors not otherwise provided for · CPC title

• B64D15/12 Primary

  by electric heating (heating arrangements specially adapted for transparent or reflecting areas H05B3/84) · CPC title