Title: Rotating machine for interaction with a gas or liquid

This invention relates to a rotating machine, both of driven and driving type, that can be applied as, e.g., a pump, compressor, generator, driving motor, wind or water turbine, etc. This machine is preferably not of the positive displacement type. A rotating machine of positive displacement type is e.g. a plunger pump. The machine is designed for interaction with a flowing fluid, such as a gas or liquid. Said fluid flows through and/or around the machine.

Presently a by the wind or water or another liquid or gas like fluid driven machine, e.g. to generate galvanic or different energy, is assumed as important application of the invention. It will however be appreciated that the invention is applicable to any possible field, e.g. as propulsion for an air or water vehicle.

This machine has many advantages, among which bird friendly and a high energetic efficiency.

The machine has a rotor with which energy is gained (such as e.g. with a wind mill) or delivered (such as e.g. with a compressor or pump) to the flowing medium. For that the rotor has one or more with the fluid interacting, e.g. by the fluid contacted, blades (or is provided by it) and can rotate around a fixed centre through which the preferably straight shaft (indeed or not physical) extends.

The rotor is preferably drivingly coupled with an energy receiving device, such as a generator, or an energy supplying device, such as a driving motor.

The one or more blades comprises a blade extending along the rotor axis according to a helix and of which the unfolded condition in the flat plane provides an around a centre spiralling and substantially continuously tapering strip. If in the unfolded condition, preferably one or more of the following aspects apply for the strip: one or more side edges of the strip follow an around the centre curving line; the strip keeps with a side edge a substantially fixed distance (e.g. radius) to the centre; the strip is free of overlaps; the strip follows no more then or exactly a single turn around the centre; the strip keeps with a side edge a continuous decreasing

distance (e.g. radius) to the centre; the strip keeps wit a side edge a distance substantially zero to the centre; the surface of the strip is such that the surface of three identical strips equals half the surface of a sphere with a radius equal to the maximum distance of a side edge of the strip to the centre; the start or end of the strip is removed.

This blade can be made by moving of the flat lying strip both ends away from each other along the rotor shaft, i.e. the shaft perpendicular to the plane in which the flat lying strip is situated. Preferably the strip is meanwhile twisted, i.e. turned around the rotor shaft or a shaft parallel to it. Preferably the location or area of an end closest to the centre is kept at fixed distance to the centre or straight line (e.g. rotor shaft) through it. The blade preferably has a substantially constant pitch along its length, i.e. per rotation unit around the rotor shaft the blade bridges a fixed distance along the rotor shaft. The pith is preferably related to the imaginary line extending between the ends of the strip and keeping an equal distance to the side edges of the strip. The blade preferably extends across a length along the rotor shaft, provided by: more than its maximum strip width, preferably more then two or more then 2.5 times its maximum strip width; and/or more than its single or double maximum diameter; and/or more than the single maximum diameter of the circle covered by its strip.

The blade preferably follows more than a single, more preferably more than two or more than 2.5 turns around the rotor shaft. The edge of an end of the blade keeps preferably along a part of its length a distance to the rotor shaft. Moving along the rotor shaft the external diameter of the blade preferably continuously increases to a maximum. Viewed from the side the blade preferably has a substantially funnel, conical or tapering end. The end with conical shape and/or larger diameter is preferably located at the downstream side of the flowing fluid.

The blade preferably has a substantially smooth shape and/or a shape without discontinuities.

When applied as wind turbine the blade brings the substantially parallel to the rotor shaft arriving wind substantially completely and allows it to escape sideways at its downstream, funnel shaped end, e.g. along the end remote from the rotor shaft.

Preferably the rotor has two, three or more of these blades which are preferably mutually nested end preferably have mutually a substantially equal angular spacing around the rotor shaft. The rotor preferably carries exclusively these blades. These blades are preferably relatively thin relative to their length and width. They are e.g. membrane, sheet or foil like. They can be made of any convenient material, e.g. metal or plastic or composite. Presently preferred is a layered material of alternating metal sheet and layers of fibre reinforced resin, e.g. of the type known as GLARE (many thin aluminium sheets, interlaced by glass fibre reinforced resin of engineering quality, e.g. epoxy) .

A presently preferred, non-limiting embodiment of a blade for the machine as wind turbine can be obtained by providing a strip of sheet like material with the shape as shown in the drawing. Of the strip extending in the plane of the drawing, the one side edge 1 follows a circle with centre 2. The opposite side edge 3 starts in the centre 2 and follows a spiral shape with continuously increasing radius from centre 2. Both side edges 1, 3 make a single turn of 360 degrees around centre 2 and smoothly approach each other to join at end 4.

The blade can be obtained by fixing side edge 3 at centre 2 at the rotor shaft (not shown) extending perpendicular to the plane of the drawing and fixing end 4 to the rotor shaft at sufficient distance to centre 2, wherein the strip swivels around the rotor shaft. The strip is also moved at the relative to end 4 opposite end 5 of side edge 1 in the same direction as end 4 and parallel to the rotor shaft out of the plane of the drawing to allow the strip at its end near centre 2 end in a smooth, in upstream direction widening funnel. Possibly the end 4 is turned according to the pitch around the rotor shaft.

According to the three dimensional shape of the blade the distance between locations 2 and 4 measures approximately 1.5 times the diameter of the circle made by the side edge 1, while location 5 is located at a radial line from the rotor shaft through location 6, wherein locations 5 and 6 keep a spacing such that the funnel shaped end makes an along the end edge 7 (remained substantially straight) extending, substantially tangential outflow gap.

According to a variant one or both ends of the strip can be eliminated.