GB2304826A

GB2304826A - A wind-or water-powered machine

Info

Publication number: GB2304826A
Application number: GB9517274A
Authority: GB
Inventors: Louis William Sanderson
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-08-26
Filing date: 1995-08-26
Publication date: 1997-03-26
Anticipated expiration: 2015-08-26
Also published as: GB9517274D0; GB2304826B

Abstract

A wind- or water-powered machine comprises a pair of sails or paddles (1, 2) secured to opposite ends of a cross-shaft (5) rotatable about its axis in a power take-off shaft (12) driven by the sails or paddles. The sails or paddles (1, 2) are angularly offset from each other by substantially 90{ on the cross-shaft (5) and are constructed and arranged so that one sail or paddle is feathered during the time that the other is subjected to the full force of the motive wind or water-power in order to ensure minimum resistance to rotation of the power take-off shaft (12). Baffles (3, 4) on the sails or paddles are acted upon by the wind or water when the respective sails are feathered.

Description

WIND- OR WATER-POWERED MACHINE This invention relates to machines for converting wind or water power into useful energy and its principal object is to provide a low-speed but high-powered machine which is equally efficient regardless of the direction in which the wind is blowing or the water flowing.

To this end, according to the invention, there is provided a wind- or water-powered machine comprising a pair of sails or paddles secured to opposite ends of a cross-shaft rotatable about its axis in a power take-off shaft driven by the sails or paddles, the sails being angularly offset from each other by substantially 900 on the cross-shaft and being so constructed and arranged that one sail or paddle is feathered during the time that the other is subjected to the full force of the motive power in order to ensure minimum resistance to rotation of the power take-off shaft.

The present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is an elevational view of a wind-powered machine according to a first embodiment of the invention; Figure 2 is a plan view of the machine of Figure 1, and Figures 3 and 4 are an elevational view and a plan view, respectively, of a wind-powered machine according to a second embodiment of the invention.

With reference to Figures 1 and 2 of the drawings, two sails 1, 2, each of which is provided with a baffle 3, 4 on one of its faces, are secured to the ends of a crossshaft 5 in such a manner that the parts 6 of the sails below the shaft 5 are of greater area than the parts 8 above the shaft. Indeed, the parts 8 may in some embodiments be omitted. The cross-shaft 5 is rotatably mounted in bearings 10 in the cross-head 11 of a tubular power take-off shaft 12 which rotates with the aid of bearings 13 on a fixed shaft 14 and is connected at its lower end to machinery to be driven. The cross-shaft 5 is prevented from rotating about its axis through more than 900 in either direction by stops 15, 16 extending from the cross-head 11 into the path of arms 17, 18 on the sails 1, 2.

In operation, with the wind blowing in the direction of the arrows, the power take-off shaft 12 is rotated in a clockwise direction, as seen in Figure 2, by the wind initially acting on the front side of the sail 1, the cross-shaft 5 being prevented from rotating about its axis by engagement of the arm 17 with the stop 15. The sail 2 is thus maintained in an end-on or feathered position in which it offers minimum resistance to the wind. As the power take-off shaft 12 turns, its rotation is taken up by the wind acting first on the baffle 3 of the sail 1 and then on the baffle 4 of the sail 2 until the shaft 12 has turned through 1800, whereupon the wind striking the rear side of the lower part 6 of the sail 1 causes the cross-shaft 5 to rotate about its axis until the sail 2 is acted upon by the wind and the sail 1 is feathered.

In the embodiment of Figures 3 and 4, the sails 1, 2 are provided with baffles 3, 30, 4, 40 on both of their faces. The two baffles 3, 30 and 4, 40 of each pair are connected together by a respective shaft 31, 41 which is mounted in a bearing (not shown) in the respective sail 1, 2 for rotation about an axis perpendicular to the axis of the cross-shaft 5. The downwind or leeward baffle 30, 40 of each pair is weighted at its upper edge to counteract the symmetry of baffle so that the rotation of the pair of baffles is effected by wind action and by gravity. The embodiment of Figures 3 and 4 operates in the same manner as that of Figures 1 and 2 but the provision of a pivoted pair of baffles on each sail reduces the resistance of the baffles when the sail is feathered.

The machine, which can also be used in a stream of water, operates at a low speed to produce great power depending on the area of the sails and baffles and their distance from the axis of the power take-off shaft 12. In one example, each sail may have an area of 200m2 and be at a distance of 50m from the axis of the shaft 12. The arrangement of the baffles ensures that the wind is fully utilised throughout the whole 360O of rotation and the arrangement of the sails on the cross-shaft is such that the shaft is always balanced and its rotation effected solely by the power of the wind.

In order to ensure that the machine will always start rotating from a dead-still condition, whatever the wind direction, two or more pairs of sails 1, 2 may be mounted on a common shaft 12. In such a case, for example, two pairs of sails 1, 2 would be mounted on respective crossshafts 5 at 900 to each other while three pairs of sails would be carried on respective cross-shafts at 600 to each other. Such arrangements would provide greater power more smoothly than two-sailed models, for relatively little additional expense.

Claims

1. A wind- or water-powered machine comprising a pair of sails or paddles secured to opposite ends of a crossshaft rotatable about its axis in a power take-off shaft driven by the sails or paddles, the sails or paddles being angularly offset from each other by substantially 900 on the cross-shaft and being so constructed and arranged that one sail or paddle is feathered during the time that the other is subjected to the full force of the motive wind or water power in order to ensure the minimum resistance to rotation of the power take-off shaft.

2. A machine according to Claim 1, in which the sails are secured to the cross-shaft in such a manner that the parts of the sails below the shaft are of greater area than the parts above the shaft.

3. A machine according to Claim 1 or Claim 2 in which the cross-shaft is rotatably mounted in a cross-head of the power take-off shaft.

4. A machine according to Claim 3, in which stops extend from the cross-head into the path of respective arms on the sails to prevent the cross-shaft from rotating about its axis through more than 900 in either direction.

5. A machine according to any one of Claims 1 to 4, in which each sail is provided with a baffle on one of its faces.

6. A machine according to any one of Claims 1 to 4, in which the sails are provided with baffles on both of their faces, the two baffles of each sail being connected together by a respective shaft mounted in the respective sail for rotation about an axis perpendicular to the axis of the cross-shaft.

7. A machine according to Claim 6, in which the downwind baffle of each sail is weighted at its upper edge to counteract the symmetry of the baffle.

8. A machine according to Claim 3, in which the power take-off shaft is tubular and rotates on a fixed shaft, the power take-off shaft being connected at its lower end to machinery to be driven.

9. A wind- or water-powered machine substantially as herein described with reference to and as illustrated in Figures 1 and 2 or Figures 3 and 4 of the accompanying drawings.