Jack system with automatic locking of the piston in high position, especially for aircraft

1. A jack system including a jack provided with a cylinder wherein slides a piston having an external end, said cylinder being provided with a first stop means, the jack system comprising: a body arranged around said jack and hinged about said external end of the piston, according to a pivot axis, said body includes second stop means and being able to occupy, relatively in relation to the jack and according to the pivot axis, a first angular position authorizing an extraction/retraction of the piston in relation to the cylinder, as well as a second angular position uniquely allowed when the piston occupies in relation to the cylinder an extracted position such that said second stop means is located beyond said first stop means in an extraction position of the piston in relation to the cylinder, the body occupying said second position providing the facing, according to the extraction position, of the first and second stop means; and

an electromagnetic attraction/repulsion device including a first element fixedly mounted on said cylinder as well as a second element fixedly mounted on said body, said device being designed to provide the displacement of the body from said first position to said second position, and inversely, by attraction/repulsion of said first and second elements.

2. The jack system set forth in claim 1 , wherein said first and second elements of said electromagnetic attraction/repulsion device are respectively a permanent magnet and a magnetic body capable of being powered electrically by a power supply belong to said device, or inversely.

3. The jack system set forth in claim 2 , wherein said device is designed to automatically provide the displacement of the body from said first position to said second position, by magnetic attraction of the first element and of the second element that is not powered electrically by said power supply.

4. The jack system set forth in claim 2 or claim 3 , wherein said device is designed to provide the displacement of the body from said second position to said first position by electromagnetic repulsion of the first element and of the second element, the second element being powered electrically by said power supply in order to generate a magnetic field providing said repulsion.

5. The jack system as set forth in claim 2 , further comprising a control module connected to said power supply of said electromagnetic attraction/repulsion device.

6. The jack system set forth in claim 5 , wherein said control module includes at least one push-button switch.

7. The jack system as set forth in claim 1 , wherein said first and second elements each take the form of an angular portion of a hollow cylinder.

8. The jack system as set forth in claim 1 , wherein said second stop means is arranged at the free end of an interior hollow rod integral with said body.

9. The jack system set forth in claim 8 , wherein when said body occupies said first angular position, said hollow rod is substantially parallel to said piston.

10. The jack system set forth in claim 8 or claim 9 , wherein said hollow rod has another end connected fixedly on one portion of the end of the body hinged on said external end of the piston.

11. The jack system as set forth in claim 1 , wherein said body forms a casing around said jack.

12. The jack system as set forth in claim 1 , further comprising a connecting brace of the system, hinged around said external end of the piston, according to said pivot axis.

13. The jack system as set forth in claim 1 , wherein said first and second elements of said electromagnetic attraction/repulsion device are respectively fixed exteriorly on an open end of the cylinder, and interiorly on an open end of the body.

14. The jack system as set forth in claim 1 , wherein said first and/or second stop means are provided with a lining forming a friction surface.

15. The jack system as set forth in claim 1 , further comprising mechanical means of backup control, making it possible to provide the displacement of the body from said second position to said first position, or inversely.

16. The jack system as set forth in claim 1 , wherein said jack is pneumatic or hydraulic.

17. The jack system as set forth in claim 1 , further comprising a pressurizing system of a fluid located in said cylinder of the jack.

18. A flap provided with an opening/closing system of the flap, wherein said opening/closing system is realized using a jack system as set forth in claim 1 .

19. An aircraft comprising at least one flap as set forth in claim 18 .

20. An aircraft comprising at least one jack system as set forth in claim 1 .