The invention relates to a mechanism for transmitting an elec¬ tric current, a fluid current or the like by means of a tubing from a stationary position to a position which is movable to and fro in relation to said stationary position, whereby said tubing is preformed into a helical configuration having a cer¬ tain elasticity. The helical tubing is placed within a rotate- able hollow drum and has the possibility to change its radial size by that the two ends of the helical tubing are twisted in relation to each other. Said one end of the helical tubing is connected to a supporting means of the drum and said second end is connected to the drum, about which an extension of the helical tubing is wound. The number of turns of the tubing on the outside of the drum is changed in correspondence with the twisting of said two ends.

A known mechanism of this kind, see US Patent 3 144 218, in¬ cludes a drum which is rotatably supported by its gables in two supporting means. An engine placed outside the drum is rotate- ing the drum via an axis, which is connected to one of said gables. The helical tubing within the drum surrounds- a statio- nary rod. This known mechanism has the disadvantage that only one single helical tubing can be placed within the drum and that it has no sensing means which determines the possible twisting in both directions of the helical tubing. The object of the invention is to avoid these disadvantages and to per- form a compact mechanism having a perfected driving engine.

According to the invention the rotating axis encompasses a reversible driving engine, the axis of which is connected to the rotating axis and the stator of which is connected to the supporting means of the drum or vice a versa, whereby the two

ends of the rotating axis are rotatably supported by beari in the supporting means.

One embodiment of the invention is shown in enclosed figs and 2 and is described below.

The tubing 1 is adapted to encompass electric lines 2 to t mit electric energy from a stationary point 3 to the drum which is rotatable in relation to said point 3. The drum 4 hollow and rotates with the axis 5, which encompasses a dr ing engine, the stator 10 of which is fixed to a supportin means 6 and the axis 11 of which is connected to the drum axis 5 by means of connecting means 12. At the left end th axis 5 is supported by bearing 16 and at the right end by pin 14 and the bearing 15. The point 3 is stationary in re tion to the supporting means 6. At the left end the drum 4 supported by the axis 5 and at the right end the drum is s ported by the supporting means 6 by means of a bearing 17.

Within the hollow drum the tubing 1 is preformed into ^' a he cal configuration, one end 7 of which is fixed to the poin while the second end 8 is connected to the inner side of t drum 4 at the left end of fig. 1. When rotating the drum 4 its axis 5 in one direction the helical tubing 1 will cont to the size shown in fig. 2 after a certain number of turn If the rotating thereafter is made in the opposite directi the helical tubing 1 will expand and will resume the size shown in fig. 1. The original form and size of the helical tubing is preferably the one according to fig. 1 and the e ticity of the tubing is so that the tubing has this form w being free in an uninfluenced condition.

The mechanism is preferably used for supplying electric en to electric means on the drum 4. An example of such means a cable 9 which is wound about the drum and this cable wi

be unwound when the drum is rotated in the one of the two directions whereby electric energy can be transmitted to an electric device which leaves the drum. This means that there is no need for a ring and guiding means between the point 3 • and-the drum, which is the usual way to transmit electric ener¬ gy between two points one of which is rotating.

It should be noted that alternative mediums can be passed through the tubing e.g. air or liquid.