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Anti-twister mechanism

The anti-twister mechanism is a method of connecting a flexible link between two objects, one of which is rotating with respect to the other, in a way that prevents the link from becoming permanently twisted. The link could be an electrical cable or a flexible pipe.

This mechanism is intended as an alternative to the usual method of supplying electric power to a rotating device, which is to use slip rings. The slip rings are attached to one part of the machine, and a set of fine metal brushes are attached to the other part. The brushes are kept in sliding contact with the slip rings, providing an electrical path between the two parts whilst allowing the parts to rotate about each other.

However, this presents problems with smaller devices. Whereas with large devices minor fluctations in the power provided through the brush mechanism are inconsequential, in the case of tiny electronic components, the brushing introduces unacceptable levels of noise in the stream of power supplied. Therefore, a smoother means of power delivery is needed.

A device designed and patented in 1971 by an American, D. A. Adams , and reported in The Amateur Scientist in December 1975, solves this problem with a rotating disk floating above a platform from which a wire extends up, over and onto the top of the disk. When the disk rotates through one complete revolution about a vertical axis, the wire unavoidably acquires a full twist. If the disk continues to rotate in the same direction through another complete turn, the wire can be passed through the space between the disk and the platform, cancelling out the previous twist and leaving the wire untwisted. This process can be repeated indefinitely, allowing the platform to rotate continuously with no more than a 360° twist in the wire.

It is unlikely that a machine in its ideal form as described above, with a floating disk, will be used in practice. Instead, various ways can be and have been devised to support the disk whilst creating a temporary gap for the wire to pass through.

01-04-2007 01:18:14
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