AIR PROPELLER ARRANGEMENT AND AIRCRAFT
An air propeller arrangement for propulsion of a fixed-wing aircraft includes a first air propeller that includes a first hub member and at least a first and a second propeller blade, the first and second blades being configured to contribute significantly to the propulsion and having a substantially equal length. Each of the blades has an inner, root end arranged at the first hub member and an outer, tip end positioned at a distance from the first hub member such that each blade extends in a radial direction from the first hub member. The first and second blades are interconnected at their outer ends. An aircraft provided with such an air propeller arrangement is also provided.
1 . Air propeller arrangement ( 10 , 30 , 50 ) for propulsion of a fixed-wing aircraft ( 8 ),
said arrangement comprising a first air propeller ( 11 , 31 , 51 ) that comprises a first hub member ( 15 , 35 , 55 ) and at least a first and a second propeller blade ( 13 , 14 , 33 , 34 , 53 , 54 ),
said first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) being configured to contribute significantly to said propulsion and having a substantially equal length,
wherein each of said blades ( 13 , 14 , 33 , 34 , 53 , 54 ) has an inner, root end ( 17 , 18 , 37 , 38 , 57 , 58 ) arranged at the first hub member ( 15 , 35 ; 55 ) and an outer, tip end ( 19 , 20 , 39 , 40 , 59 , 60 ) positioned at a distance from the first hub member ( 15 , 35 , 55 ) such that each blade ( 13 , 14 , 33 , 34 , 53 , 54 ) extends in a radial direction from the first hub member ( 15 , 35 , 55 ),
characterized in
that the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) are interconnected at their outer ends ( 19 , 20 , 39 , 40 , 59 , 60 ).
2 . Arrangement ( 10 , 30 , 50 ) according to claim 1 ,
characterized in
that the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) are interconnected via an interconnecting member ( 27 , 47 , 67 ) extending between said outer ends ( 19 , 20 , 39 , 40 , 59 , 60 ) of the blades ( 13 , 14 , 33 , 34 , 53 , 54 ).
3 . Arrangement ( 10 , 30 , 50 ) according to claim 2 ,
characterized in
that the interconnecting member ( 27 , 47 , 67 ) forms an integral part of the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ).
4 . Arrangement ( 10 , 30 , 50 ) according to claim 2 or 3 ,
characterized in
that the interconnecting member ( 27 , 47 , 67 ) has the shape of a continuous curvature.
5 . Arrangement ( 10 , 30 , 50 ) according to anyone of the above claims,
characterized in
that the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) are spaced in a circumferential direction of the first hub member ( 15 , 35 , 55 ).
6 . Arrangement ( 10 , 30 , 50 ) according to anyone of the above claims,
characterized in
that the root ends ( 17 , 18 , 37 , 38 , 57 , 58 ) of the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) are separated from each other.
7 . Arrangement ( 10 , 30 , 50 ) according to anyone of the above claims,
characterized in
that the root ends ( 17 , 18 , 37 , 38 , 57 , 58 ) of the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) are spaced in a circumferential direction of the first hub member ( 15 , 35 , 55 ).
8 . Arrangement ( 10 , 30 , 50 ) according to anyone of the above claims,
characterized in
that the root ends ( 17 , 18 , 37 , 38 , 57 , 58 ) of the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) are spaced in an axial direction of the first hub member ( 15 , 35 , 55 ).
9 . Arrangement ( 10 , 30 , 50 ) according to anyone of the above claims,
characterized in
that at least one of the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) is swept.
10 . Arrangement ( 10 , 30 , 50 ) according to claim 9 ,
characterized in
that at least one of the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) is configured in such a way that its tip end ( 19 , 20 , 39 , 40 , 59 , 60 ) is displaced in relation to its root end ( 17 , 18 , 37 , 38 , 57 , 58 ) in relation to an axial direction of the first hub member ( 15 , 35 , 55 ).
11 . Arrangement ( 10 , 30 , 50 ) according to anyone of the above claims,
characterized in
that both the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) are swept.
12 . Arrangement ( 10 , 30 , 50 ) according to claim 11 ,
characterized in
that each of the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) is configured in such a way that its tip end ( 19 , 20 , 39 , 40 , 59 , 60 ) is displaced in relation to its root end ( ) in an axial direction of the first hub member ( ).
13 . Arrangement ( 10 , 30 , 50 ) according to claim 12 ,
characterized in
that the first and second blades ( 13 , 14 , 33 , 34 , 53 , 54 ) are swept in the same direction.
14 . Arrangement ( 10 , 30 , 50 ) according to claim 13 ,
characterized in
that the direction in which the tip end ( 19 , 39 , 59 ) of the first blade ( 13 , 33 , 53 ) is displaced in relation to its corresponding root end ( 17 , 37 , 57 ) is the same as the direction in which the tip end ( 20 , 40 , 60 ) of the second blade ( 14 , 34 , 54 ) is displaced in relation to its corresponding root end ( 18 , 38 , 58 ).
15 . Arrangement ( 10 , 30 , 50 ) according to anyone of claims 9 - 14 ,
characterized in
that the first and/or the second blade ( 13 , 14 , 33 , 34 , 53 , 54 ) is curved in the axial direction of the first hub member ( 15 , 35 , 55 ) and/or that the first and/or the second blade ( 13 , 14 , 33 , 34 , 53 , 54 ) is inclined in relation to the axial direction of the first hub member ( 15 , 35 , 55 ).
16 . Arrangement ( 10 , 30 , 50 ) according to anyone of the above claims,
characterized in
that the first air propeller ( 11 , 31 , 51 ) comprises a plurality of pairs of propeller blades, wherein each of said blade pairs comprises a first and a second blade ( 13 , 14 , 33 , 34 , 53 , 54 ) according to anyone of the above claims.
17 . Arrangement ( 10 , 30 , 50 ) according to claim 16 ,
characterized in
that the blade pairs are circumferentially distributed around the first hub member ( 15 , 35 , 55 ).
18 . Arrangement ( 10 , 30 , 50 ) according to anyone of the above claims,
characterized in
that it comprises a second air propeller ( 12 , 32 , 52 ) arranged in association with the first air propeller ( 11 , 31 , 51 ), wherein the second air propeller comprises a second hub member ( 16 , 36 , 56 ) and at least a third and a fourth propeller blade ( 23 , 24 , 43 , 44 , 63 , 64 ) that extend radially from the second hub member ( 16 , 36 , 56 ).
19 . Arrangement ( 10 , 30 , 50 ) according to claim 18 ,
characterized in
that the third and fourth blades ( 23 , 24 , 43 , 44 , 63 , 64 ) are configured to contribute significantly to said propulsion.
20 . Arrangement ( 10 , 30 , 50 ) according to claim 18 or 19 ,
characterized in
that the third and fourth blade ( 23 , 24 , 43 , 44 , 63 , 64 ) have a substantially equal length.
21 . Arrangement ( 10 , 30 , 50 ) according to anyone of claims 18 - 20 ,
characterized in
that each of the third and fourth blades ( 23 , 24 , 43 , 44 , 63 , 64 ) has an inner, root end arranged at the second hub member ( 16 , 36 , 56 ) and an outer, tip end ( 25 , 26 , 45 , 46 , 65 , 66 ) positioned at a distance from the second hub member ( 16 , 36 , 56 ).
22 . Arrangement ( 10 , 30 , 50 ) according to claim 21 ,
characterized in
that the third and fourth blades ( 23 , 24 , 43 , 44 , 63 , 64 ) are interconnected at their tip ends ( 25 , 26 , 45 , 46 , 65 , 66 ).
23 . Arrangement ( 10 , 30 , 50 ) according to anyone of claims 18 - 22 ,
characterized in
that the first and second hub members ( 15 , 16 , 35 , 36 , 55 , 56 ) are concentrically arranged.
24 . Arrangement ( 10 , 30 , 50 ) according to anyone of claims 18 - 23 ,
characterized in
that the second air propeller ( 12 , 32 , 52 ) is arranged to rotate in an opposite direction in relation to the first air propeller ( 11 , 31 , 51 ).
25 . Arrangement ( 10 , 30 , 50 ) according to anyone of claims 18 - 23 ,
characterized in
that the second air propeller ( 12 , 32 , 52 ) is arranged according to anyone of claims 2 - 17 , wherein the first blade ( 13 , 33 , 53 ) corresponds to the third blade ( 23 , 43 , 63 ), wherein the second blade ( 14 , 34 , 54 ) corresponds to the fourth blade ( 24 , 44 , 64 ), and wherein the first hub member ( 15 , 35 , 55 ) corresponds to the second hub member ( 16 , 36 , 56 ).
26 . Arrangement ( 10 , 30 , 50 ) according to claim 13 and anyone of claims 18 - 23 ,
characterized in
that both the third and fourth blades ( 23 , 24 , 43 , 44 , 63 , 64 ) are swept and that they are swept in the same direction.
27 . Arrangement ( 10 , 30 , 50 ) according to claim 26 ,
characterized in
that the first, second, third and fourth blades ( 13 , 14 , 23 , 24 , 33 , 34 , 43 , 44 , 53 , 54 , 63 ; 64 ) are all swept in a forward direction, wherein forward direction is related to an intended general direction of propulsion.
28 . Arrangement ( 10 , 30 , 50 ) according to anyone of the above claims,
characterized in
that an axial direction of the first hub member ( 15 , 35 , 55 ) substantially coincides with an intended general direction of propulsion.
29 . Aircraft ( 8 ),
characterized in
that it comprises an air propeller arrangement ( 10 , 30 , 50 ) according to anyone of the above claims.
30 . Aircraft ( 8 ) according to claim 29 ,
characterized in
that the propeller arrangement ( 10 , 30 , 50 ) is arranged to the aircraft ( 8 ) in such a way that an axial direction of the first hub member ( 15 , 35 , 55 ) substantially coincides with the intended general direction of travel of the aircraft ( 8 ).