Method and device for removing material from a power line wire
A travelling wave motion is formed in a power line wire, which wave motion loosens material, like snow or ice, on the surface of the wire. A first support point and a second support point are arranged on the wire course, the distance of which support points being substantially smaller than the distance between the adjacent support posts of the power line, and the course of the wire is changed on the part between the support points. Then the wire is suddenly returned into its original course, which evokes a longitudinal and/or transverse wave motion in the wire. The course of the wire can be changed by applying a force on the wire between the first and second support points, in a direction transverse to the longitudinal direction of the wire. Thus the wire is returned into its original course by suddenly removing the force applied into the wire. In implementing of the method can a device hung on a wire be used, which device comprises a flame, a first support roll, a second support roll and a transfer roll movable in relation to the support rolls.
1. A method for removing material from a surface of a power line wire, in which method a wave motion travelling along the power line wire is created in the power line wire by applying an impulse thereto, comprising:
arranging a first support point and a second support point on an original course of the power line wire supported between adjacent support posts projecting from a support surface, a distance between the first support point and the second support point being substantially smaller than a distance between the adjacent support posts supporting the power line;
changing the original course of the power line wire on a part thereof between the first support point and the second support point when snow or ice is accumulated on the power line wire; and
returning the power line wire into the original course resulting in the wave motion travelling in opposite directions along the power line wire to make the power line wire vibrate causing the removal of material therefrom.
2. The method according to claim 1 , wherein the original course of the power line wire is changed by applying a force on the power line wire between the first support point and the second support point in a direction transverse to a longitudinal direction of the power line wire and by returning the power line wire into the original course by removing the force applied to the power line wire.
3. The method according to claim 1 , wherein the first support point and the second support point are arranged close to a midpoint of two adjacent support posts supporting the power line wire.
4. The method according to claim 1 , wherein the first support point and the second support point are arranged at a distance of less than 2.0 meters from each other.
5. The method according to claim 1 , wherein the original course of the power line wire on the part between the first support point and the second support point is changed less than 20 mm.
6. The method according to claim 1 , wherein the method is used for loosening snow and/or ice attached on the power line wire from the surface thereof.
7. The method according to claim 1 , wherein the first support point and the second support point are fixed in use on opposite ends of the part of the power wire line.
8. The method according to claim 1 , wherein the original course of the power line wire is changed by selectively controlling a force isolated on the part of the power line wire between the first support point and the second support point.
9. The method according to claim 8 , wherein the power line wire is returned automatically to the original course by stopping the force isolated on the part of the power line wire.
10. A device for loosening snow and/or ice from a surface of a power line wire, the device comprising: a frame, a first support roll, a second support roll, wherein the first support roll and the second support roll are attached with a bearing into the frame at a distance from each other, and an arrangement configured to direct an impulse into the wire, wherein the device further comprises a transfer roll movable from an original position in relation to the first support roll and the second support roll, and a motor for moving the transfer roll when snow or ice is accumulated on the power line wire, wherein the transfer roll is movable in a transverse direction of the power line wire between the first support roll and the second support roll for changing an original course of the power line wire over a distance between the first support roll and the second support roll, wherein the transfer roll is returned into the original position to return the power line wire into the original course, the device being configured to provide a wave motion travelling in opposite directions along the power line wire to make the power line wire vibrate causing the loosening of snow and/or ice therefrom.
11. The device according to claim 10 , wherein the device is hung on the power line wire such that the first support roll and the second support roll are placed on a first side of the power line wire and the transfer roll is placed on a second side of the power line wire.
12. The device according to claim 10 , wherein the distance between the first support roll and the second support roll is less than 2.0 meters.
13. The device according to claim 10 , wherein the motor for moving the transfer roll is an electric motor and the device comprises a power source for arranging driving power to the motor.
14. The device according to claim 10 , wherein the device comprises a battery for storing electrical energy.
15. The device according to claim 14 , wherein the device comprises a charger for producing charging current of the battery from a magnetic field created by the power line wire.
16. The device according to claim 10 , wherein the device comprises wireless control to control the operation of the device.
17. The device according to claim 10 , wherein the device comprises a weatherproof, substantially closed casing.
18. The device according to claim 10 , wherein the transfer roll is drivingly connected to the motor to move the transfer roll in the transverse direction of the power line wire.
19. The device according to claim 10 , wherein the transfer roll is connected to a bar which is movably mounted on the frame and configured to be drivingly connected to the motor.
20. The device according to claim 10 , wherein the transfer roll is movable outside the frame.