GB2462618A

GB2462618A - Wind-motor with vertically-hinged flaps

Info

Publication number: GB2462618A
Application number: GB0814766A
Authority: GB
Inventors: Samuel Goddard
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-08-12
Filing date: 2008-08-12
Publication date: 2010-02-17
Also published as: GB0814766D0

Abstract

A vertical-axis wind motor comprises blades / sails 4A, 4B of vertically-hinged flaps within frames 3, i.e, the flaps swing horizontally. Each frame may have more than one flap pivoted in a vertical orientation, the flaps being parallel to each other. Ideally, the flaps are freely pivoted and are moved only by the force of the wind 1A, 1B or flowing fluid. A limiter-stop may be used to restrict the angle to which the flaps open. This concept is also envisaged being utilized in a water flow.

Description

Vertical-hinged Flap Windmill This invention solves the problem of opposite arms of a vertical-axis windmill creating opposing forces and hence not harnessing the maximum amount of energy available. In the past vertical-axis windmills have either specially shaped arms so as they collect more of the force of the fluid when hit from one side as they do from the other, or they have separate structures to channel the fluid that would have hit one side of the windmill towards the other, but both of these solutions have their drawbacks.

To create a system where the force generated by fluid hitting one side of the windmill is not opposed by an equal amount of force hitting the opposite arm this invention consists of a system whereby a vertically-hinged flap or flaps will open on one side of the windmill allowing fluid to pass without resistance.

This allows any energy collected on one half of the windmill to be collected without opposition from the opposite arm. It is also preferable to having horizontally hinged flaps as a flap hinged at the top will still require a certain amount of force to overcome the force of gravity acting on the flap, and all of the energy used to do this will be subtracted from that which can be harnessed from the system as a whole.

Preferably, the windmill will have four arms. This is the conventional number for a vertical-axis windmill and it means there is always an arm perpendicular, or nearly perpendicular to the direction of the wind.

Preferably, the flaps are hinged on the outside, so that the flow of fluid cannot get between the flap and the structure of the arm. The hinges are always vertical.

This idea could be applied to any moving body of fluid, be it wind, water or another.

An example of the invention will now be described by referring to the accompanying drawings: * Figures 1 and 2 are a plan and front view respectively of a conventional vertical axis windmill without any channelling system and with four solid arms (3) attached to a central column (2). They illustrate the moving fluid (1) hitting opposite arms and hence creating no turning moment about the central column.

* Figure 3 shows an isometric view of the invention in place on the same vertical axis windmill, this time with the flaps (4) either being forced into to the arms structure (3, 4A) or allowed to swing into the lee of the moving fluid (4B). The figure also illustrates how this allows the moving fluid to hit the arm on one side (1A) and pass through the arm on the opposite side (1B). This will create a more effective turning moment about the central column (2) and is the essence of the invention.

* Figures 4 and 5 are the same views as in figure 1 and 2 but with the proposed invention.

They show, as figure 3, the flaps (4) being either forced into the arms structure (3, 4A) or allowed to swing into the lee of the moving fluid (4B).

* Figure 6 shows a single arm separate from the rest of the windmill, with the flap (4) in a hinged position, away from the arms structure (3). It also illustrates the vertical hinges by which the flap is attached (5).

The flaps are always seated and attached on the same face of the arms structure, either the left-hand side looking from the central column, to create clockwise rotation looking from above; or the right-hand side of the arms structure looking from the central column to create an anticlockwise moment about the central column.

The turning moment created by the invention can then be used to drive a mechanical or electricity generating system. An axle can be put through the central column (2) and attached to the mechanism to be driven at the bottom, top, or both, but the windmill must be operated with the central column vertical. In this way stability of the windmill can be guaranteed during operation. A variation of this invention could include having two or more vertically hinged-flaps overlapping and between them covering the space inside the arms structure (3). If this were the case supporting struts would be needed between the outer downward section of the arms structure (3A) and the central column (2).

The windmill may be constructed from any material or combination of materials. The one showing in figures 1-6 is made of wood with the pieces shaped to fit together and thin wooden flaps. A metal version could be welded together or otherwise permanently or non-permanently fixed. If the structure of the windmill was held together primarily by nuts and bolts it would be possible to de-assemble the product for transport.

The movement of the flaps is not in any way mechanically operated by the rotation of the windmill itself, and it caused by the wind only. An alternative embodiment would include attaching a limiter onto the arms structure which will only allow certain degrees of movement, be it 1800 or another pre-set angle.

Claims

Claims 1. A vertical-axis windmill on which the sails consist of vertically-hinged flaps mounted on a solid frame, which are either pushed into the frame of the sail by the moving fluid, or allowed to swing into the lee of the moving fluid, the second allowing minimum resistance to the rotation of the windmill.
2. A vertical-axis windmill according to claim 1, on which there is one or more vertically hinged flaps attached to the frame of each of the sails.
3. A vertical-axis windmill according to claim 2, on which multiple flaps overlap along the length of the sail, all being hinged vertically and parallel to one another.
4. A vertical-axis windmill according to claim 1, on which there are any number of sails, or arms, all of which comprise of any number of vertically-hinged flaps, according to claim 3.
5. A vertical-axis windmill according to claim 1 and claim 2, on which the flaps are moved in position only by the force of the moving fluid and not any mechanical system that opens or closes the flaps depending upon their position.