This invention relates to a vertical shaft windmill with a governor. BACKGROUND OF THE INVENTION

Vertical windmills are well known and examples are shown in US Application No: 2008/01311281 (Kariya) published June 5 ^th , 2008 and in US Patent

No: 7,094,017 (Kurita) issued August 22, 2006 and in many other prior patents some of which are referenced in the above documents. All these documents are incorporated herein by reference for further details of such a vertical windmill which may be used herein. Such windmills are typically known under the name Savonius type windmills.

SUMMARY OF THE INVENTION

It is one object of the invention to provide a governor for a vertical windmill.

According to one aspect of the invention there is provided a vertical axis windmill apparatus comprising: a rotor assembly that rotates about an upstanding axis including a plurality of rotor blades wherein each of said rotor blades has a concave and a convex side; a wind control governor comprising a plurality of wind channelling devices positioned at least partly around the circumference of the rotor so as to face an incoming wind; wherein said plurality of wind channelling devices are adjustable in angle each about a respective vertical axis so as to control and direct winds toward said concave side of said rotor blades to cause said rotor blades to rotate the shaft at a controlled rate regardless of wind direction or wind speed.

Preferably the plurality of said wind channelling devices are interconnected using parallel linkage for common adjustment. However some or all may be adjusted in groups or independently for more accurate control depending on the wind direction.

Preferably the plurality of said wind channelling devices pivot on a superstructure which also supports the rotor. However they may be mounted independently of the support for the rotor.

Preferably the plurality of said wind channelling devices are arranged in a closed position such that side edges thereof intersect each other sealing said rotor from wind rendering it inert.

Preferably the plurality of said wind channelling devices are arranged to increase or decrease air flow through said rotor governing the speed of said rotor.

Preferably the plurality of said wind channelling devices are arranged direct air to and increase pressure on said concave side of said rotor and decrease pressure on said convex side of said rotor thus increasing power.

Preferably each wind channelling device comprises a panel defining an outer surface for engaging the incoming air.

Preferably the panel defines a front surface and a rear surface so that the front surface faces the incoming wind. Such a construction is preferably shaped in horizontal cross section so that the surfaces are spaced by a maximum distance at a vertical center line and are tapered toward one another so that the panel is narrower or even sharpened at the side edges. The front and rear surfaces may be symmetrical. However the front and rear surfaces of the panel may be flat Preferably the devices are arranged around the full periphery of the rotor. However there may be only such devices as group on one side mounted in a manner which allows the group to be rotated to face the wind.

Preferably there is a superstructure defined by a series of towers with each device mounted on a respective one of the towers. Preferably each device is pivotal about an axis part way across its width and preferably at a center line. However it may be pivoted about one edge.

Preferably each device pivots from a closed position extending generally at right angles to a radius of the rotor to an inclined angle directing air onto the concave side of the rotors. The following additional alternative arrangements are also included herein:

This design can have any number of the wind channelling devices or doors.

The wind channelling devices do not have to pivot in the center. They can for example pivot on the inside edge or outside edge.

The wind channelling devices do not necessarily have to be flat. They could be thicker in the middle and tapering towards the ends, or they could be curved.

The rotor does not necessarily have to be hung from the top of the super structure, it could for example be supported completely at the base.

The wind channelling devices do not necessarily have to be pivoted on the super structure.

Parallel linkage could be attached in many places on the wind channelling devices including the inward and outward edge of the wind channelling devices.

The wind channelling devices or doors do not necessarily have to be interconnected.

The wind channelling devices do not necessarily have to adjust equally.

The rotor can be made to turn clockwise or counterclockwise. BRIEF DESCRIPTION OF THE DRAWINGS One embodiment of the invention will now be described in conjunction with the accompanying drawings in which:

Figure 1 is an isometric view of a vertical shaft windmill with governor according to the present invention.

Figure 2 is an isometric view of the rotor of the windmill of Figure 1 showing the rotor with its concave and convex sides.

Figure 3 is an isometric view of the superstructure, the wind channelling devices, and parallel linkage interconnecting the wind channelling devices of the windmill of Figure 1.

Figure 4 is a schematic plan view of the wind channelling devices in the open and closed positions and the arc path that they travel.

Figure 5 is a schematic plan view of the wind channelling devices in the open positions and including a connecting operating linkage.

Figure 6 to 9 are schematic plan views of the wind channelling devices at various stages of adjustment.

Figure 10 is a schematic plan view of an embodiment of the apparatus which includes 16 of the wind channelling devices shown in the open position. Figure 11 is a schematic plan view of an embodiment of the apparatus which includes 8 of the wind channelling devices shown pivotal about one edge.

Figure 12 is a schematic plan view of an embodiment of the apparatus which includes 8 of the wind channelling devices shown pivotal about the opposite edge. In the drawings like characters of reference indicate corresponding parts in the different figures. DETAILED DESCRIPTION

The windmill best shown in Figure 5 comprises a typical rotor of the type generally known as a Savonius windmill which includes a vertical rotor 10 mounted for rotation about a vertical axis 11 with a plurality of angularly spaced vertically extending blades 12 around the axis. Each blade 12 has a concave side

13 and a convex side 14 so that it tends to rotate around the axis in a counterclockwise direction as shown with the concave side leading.

The rotor drives a suitable power output (not shown) through an output gear box (not shown).

The rotor is mounted in suitable bearings which may or may not include a superstructure supporting the upper end.

The arrangement of the present invention comprises a governor 20 in the form of a plurality of wind channelling devices 21 arranged at spaced positions around the axis. The wind channelling devices each comprise a panel which stands vertically along the full height of the rotor so as to engage and direct the air approaching the rotor. Each panel has an outer or front surface for engaging the wind on the inlet side and a rear surface for engaging the wind on the outlet side of the rotor.

In Figure 6 the panels are in the closed position. No wind is affecting the windmill rotor. The rotor is inert. In Figure 7 the panels are slightly open. This setting would be used for high wind speeds. The rotor turns counter clockwise.

In Figure 8 the panels are open more than in Figure 7. This setting would be used for lower wind speeds than Figure 7. The rotor turns counter clockwise. In Figure 9 the panels are in the fully open position. This setting would be used for marginal wind speeds.

The wind channelling devices are channelling wind to increase pressure on the concave side of the rotor and channelling wind away from and decreasing pressure on the convex side of the rotor thus maximising power. The rotor turns counter clockwise.

Since various modifications can be made in my invention as herein above described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without department from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense.