Exterior cleaning machine in wind turbine-towers

1. A system which comprises an exterior cleaning machine for cleaning a metallic wind turbine tower, wherein said machine comprises the following components:

(a) at least one flexible roller ( 2 a , 2 b ) configured to come in contact with part of the surface of the mast ( 1 ) of a wind turbine;

(b) a plurality of magnets ( 3 ) facing part of the outer surface of the mast ( 1 ) and configured to attract said machine with regard to the mast ( 1 );

(c) at least one tank ( 4 a , 4 b ) configured to hold a cleaning product;

(d) a plurality of rolling means ( 5 ) located between a structure and the mast ( 1 );

(e) remote control means ( 6 ) of the lifting motion of said machine which are associated with said lifting means ( 7 );

(f) a sponge ( 8 ) located in the vicinity of said at least one flexible roller ( 2 a , 2 b ), and configured to absorb some of the cleaning product retained in said at least one flexible roller ( 2 a , 2 b );

(g) a receptacle ( 10 ) inferiorly located with regard to said at least one flexible roller ( 2 a , 2 b ), and configured to collect waste products after cleaning of the mast by gravitational action; and

(h) a frame ( 13 ) that encompasses the components (a)-(g) and on which the components (a)-(g) are positioned, said frame being coupled to lifting means ( 7 ) for lifting the frame in a direction parallel to the mast ( 1 ) of the wind turbine.

2. System which comprises an exterior cleaning machine according to claim 1 , wherein said lifting means ( 7 ) comprise a motor-operated hoist anchored, on the one hand, to the top portion of the mast ( 1 ) and, on the other, to the base of the mast ( 1 ), and coupled, in turn, to the cleaning machine itself.

3. System which comprises an exterior cleaning machine according to claim 1 , wherein said at least one tank ( 4 a , 4 b ) is associated with a pumping element of the cleaning product to be housed inside said tank ( 4 a , 4 b ), said pumping being controlled via said remote control means ( 6 ).

4. System which comprises an exterior cleaning machine according to claim 1 , wherein said at least one flexible roller ( 2 a , 2 b ) is coupled to a motor ( 7 a , 7 b ) configured to rotate said flexible roller ( 2 a , 2 b ) via its axis of rotation, said rotation being controlled via said remote control means ( 6 ).

5. System which comprises an exterior cleaning machine according to claim 1 , wherein said sponge ( 8 ) is coupled to a motor configured to alternately move said sponge ( 8 ) with regard to the static position of the axis of rotation of the flexible roller ( 2 a , 2 b ), and said alternate motion being controlled via said remote control means ( 6 ).

6. System which comprises an exterior cleaning machine according to claim 1 , and further comprising a retractable lip ( 9 ) located in the vicinity of said at least one flexible roller ( 2 a , 2 b ), which has two operating positions:

a first cleaning position, wherein the retractable lip ( 9 ) is in contact with the surface of the mast ( 1 ); and

a standby position, wherein the retractable lip ( 9 ) is separated a distance with regard to the surface of the mast ( 1 ).

7. System which comprises an exterior cleaning machine according to claim 1 , wherein said at least one flexible roller ( 2 a , 2 b ) comprises an anti-projection screen ( 11 ), said screen ( 11 ) being configured to direct the used cleaning product towards the lower receptacle.

8. System which comprises an exterior cleaning machine according to claim 1 , further comprising a safety system against failures of said lifting means ( 7 ), wherein said safety system has at least one tie wire anchored, on the one hand, to the machine and, on the other, to the top portion of the mast ( 1 ).

9. System which comprises an exterior cleaning machine according to claim 1 , wherein the cleaning product is a detergent.

10. System which comprises an exterior cleaning machine according to claim 1 , wherein the cleaning product is a defoamer.

11. An exterior cleaning process on wind turbine towers of the system defined in claim 1 , wherein said process comprises the following steps:

a) coupling the machine to the corresponding lifting means ( 7 ) with regard to the mast ( 1 ) of the wind turbine;

b) positioning the machine in the vicinity of the outer surface of the mast ( 1 ), facing the plurality of magnets ( 3 ) with respect to said surface, attracting the machine to the surface of the mast ( 1 ) through the existing magnetic forces, and contacting the rolling means ( 5 ) with said surface of the mast ( 1 );

c) injecting the cleaning product onto said at least one flexible roller ( 2 a , 2 b );

d) rotating said at least one flexible roller ( 2 a , 2 b ) in contact with part of the surface of the mast ( 1 ); and

e) actuating, via said remote control means ( 6 ), the lifting of said machine.

12. The system of claim 1 , wherein the at least one flexible roller comprises means for retaining the cleaning product and for applying the cleaning product to the surface of the mast of the wind turbine to clean the surface.

13. The system of claim 12 , wherein the plurality of magnets are configured to attract the machine to the tower to insure that the at least one flexible roller stays in fixed contact with the surface of the tower.

14. The system of claim 13 , wherein said at least one tank is associated with a pumping element for pumping the cleaning product from the at least one tank to the at least one flexible roller.

15. The system of claim 14 , wherein the at least one flexible roller is coupled to a motor configured to rotate said flexible roller around an axis of rotation of the at least one flexible roller.