GB2129881A

GB2129881A - Wind motor

Info

Publication number: GB2129881A
Application number: GB08232371A
Authority: GB
Inventors: John Watson Taylor
Original assignee: University of Leeds
Current assignee: University of Leeds
Priority date: 1982-11-12
Filing date: 1982-11-12
Publication date: 1984-05-23
Also published as: GB2129881B

Abstract

The motor comprises an assembly which is rotatable as a whole about a first axis Q-Q', said assembly including at least one sail or other wind-pressure surface 10, 12 which is rotatable about an axis 14, 16 spaced from and parallel to said first axis Q-Q', said sail or other wind-pressure surface being mounted between spaced crosshead assemblies 6, 8 between which there is no connection on said first axis Q-Q', the orientation of said sail or other wind-pressure surface relative to the plane of said axes being controlled, via a chain or gear device 34, from an idler wheel 28 located on said first axis, by a wind vane which follows the instantaneous direction of the wind. <IMAGE>

Description

SPECIFICATION Wind motor This invention relates to wind motors.

There have been many proposals for wind motors, but many of such proposals have suffered various disadvantages, particularly in those motors usually classed as vertical axis motors and having orientable vanes or sails. Perhaps the most important of these disadvantages is that because the wind motors are provided with a central column to which the vanes or sails of the motor are connected, the size and particularly the width of the vanes or sails are limited by the distance between the axis of rotation of the vane or sail and the central column. Of necessity, the half width of the vanes or sails must be less than this distance in order to allow the vanes or sails to rotate freely about their axes of rotation and relative to the central column, and this limits the potential power output from the motor.

The present invention seeks to obviate this and other disadvantages of known wind motors by providing an improved form of wind motor.

According to the present invention, there is provided a wind motor comprising an assembly which is rotatable as a whole about a first axis, said assembly including at least one sail or other wind-pressure surface which is rotatable about an axis spaced from and parallel to said first axis, said sail or other wind-pressure surface being mounted between spaced crosshead assemblies between which there is no connection on said first axis, the orientation of said sail or other wind-pressure surface relative to the plane of said axes being controlled, via a chain or gear device from an idler wheel located on said first axis, by a wind vane which follows the instantaneous direction of the wind.

Preferably, said axes will be vertical.

The movement of the sail or other windpressure surface about its axis of rotation will be in an opposite direction to the direction of rotation of the assembly about said first axis, the speed of rotation of the sail or other wind-pressure surface being less than the speed of rotation of said assembly.

The sail or other wind-pressure surface will preferably be mounted in upper and lower crosshead assemblies, the lower crosshead assembly being rigidly connected to a shaft on said first axis of rotation. The crosshead assemblies will preferably consist of open framework to reduce wind resistance.

The sail will preferably carry a sprocket wheel which via an endless chain or notched belt is connected to the idler wheel to provide the rotational speed ratio between the assembly and the sail or wind-pressure surface. Alternatively this may be achieved by a train of gears.

The idler wheel will preferably be mounted on the first axis such that it may remain static upon rotation of the assembly about the first axis but such that it may rotate about said first axis upon movement of the wind vane about said first axis.

In a particularly preferred embodiment of the invention, the rotatable assembly will include two sails or other wind-pressure surfaces mounted for rotation between upper and lower crosshead assemblies which extend to either side of the first axis, said sails or surfaces being connected to an idler wheel through the intermediaries of chains or gear trains.

The sails or other wind-pressure surfaces, irrespective of their dispositions relative to said first axis, will preferably be located and remain in substantially normal dispositions relative to each other.

The wind vane will preferably consist of a lower part rigidly connected to an upper part in order that the vane may follow more effectively the mean direction of the wind which is incident on the assembly.

In order that the invention may be more readily understood, an embodiment thereof will now be described, by way of example, reference being made to the accompanying drawings, in which: Figure 1 is a diagrammatic illustration of a vertical wind motor according to the invention; Figure 2 is a sectional elevation on line P--P in Figure 1; Figure 3 is a sectional elevation on line O--Q in Figure 1; Figure 4 is a view on line R--R in Figure 3; Figures 5 to 8 are plan views showing successive positions of the sails during operation of the wind motor shown in Figures 1 to 4.

Referring to the drawings, and firstly to Figures 1 to 4, the wind motor comprises an assembly indicated generally by reference numeral 2 which is rotatable as a whole, about a first vertical axis 4.

The assembly comprises upper and lower crosshead assemblies 6 and 8 which mount between them two pressure surfaces -- sail assemblies 10 and 12 - which are normal, one to the other, which occupy (in plan view) varying dispositions relative to the first vertical axis 4 and upon which the wind acts to cause rotation of the assembly 2 about said first vertical axis 4.

Sail assemblies 10 and 12 are rotatable relative to the crosshead assemblies 6 and 8, about vertical axes 14 and 1 6 which are mutually parallel and also parallel to the first vertical axis 4, sail beams 1 0A and 1 2A mounting the sails 1 OB, and 1 2B being journalled in bearings (not shown) in or on the upper and lower crossheads 6 and 8.

A main shaft of the assembly is located on the first vertical axis 4 and comprises a first lower portion 20 and second upper portion 22, which are rigidly secured to the crossheads 8 and 6 respectively such that the crossheads and shaft portions are only rotatable together. The lower shaft portion 20 (from which power may be taken) is journalled for rotation in a main bearing (not shown), and the upper shaft portion 22 is journalled for rotation in a subsidiary bearing, not shown.

Because there is no central portion to the main shaft, i.e. there is no central column or connection between the crosshead assemblies on the first vertical axis, the width of the sails 1 OB and 128 can be the maximum possible dimension to allow relative rotation of the sails without fouling each other.

Connected to the upper and lower portions 22 and 20 of the main shaft is a wind vane assembly consisting of wind vanes 40 and 42 carried on a common rigid link 44, tie members 46 and 48 being provided which, in combination with outwardly extending members 50 and 52, serve to brace the wind vane assembly. The wind vane assembly is connected to the upper and lower portions of the main shaft by link arms 54 and 56 carried respectively by bearings 24 and an auxiliary bearing 58 to enable the wind vane assembly to rotate relative to the main shaft portions substantially within the swept volume of the assembly 2.

An idler wheel 28, having two spaced-apart rows 30 and 30A of teeth so as to constitute a two-sprocket composite idler wheel, is located on the lower portion 20 of the main shaft such that it may rotate relative to the main shaft. Endless chains 32 and 34 extending from the rows 30 and 30A of teeth on the idler wheel 28 connect the idler wheel to sprocket wheels 36 and 38 mounted on the lower ends of sail beams 1 OA and 1 2A respectively. The ratio of the sprocket wheels 36 and 38 to the rows of teeth 30 and 30A is preferably 2 :1, such that each sail assembly 10 and 12 rotates at one-half the rotational speed of the assembly as a whole, but in the opposite direction.

The idler wheel and chain drive controls the orientation of each sail assembly, and due to the connection to the idler wheel of the said vane assembly which is orientated to the instantaneous direction of the wind, the orientation of the sail assembly is also controlled by the instantaneous direction of the wind.

The directly-coupled assembly, i.e. the wind vane assembly and the sail assemblies, is set such that when the plane of the crosshead assemblies 6 and 8 lies perpendicular to the direction of the wind, one sail assembly lies approximately in this plane and the other sail assembly lies approximately parallel to the wind direction.

The ratio of the speeds of the rotation of the crosshead assemblies and shaft portions and the sail assemblies has the effect of maintaining each sail assembly 10 and 12 orientated so as to generate torque on the shaft portion 20 throughout much of each revolution of this shaft.

In addition, although the wind direction may change continuously, the optimum orientation of the sail assemblies 10 and 12 is maintained via the idler wheel.

It will be appreciated that the bearing in which the upper portion 22 of the main shaft is journalled will require bracing to prevent sideways movement, such bracing being provided by for example guy-ropes (not shown) or for example by means of a beam projecting from a building (not shown) where the assembly is situated in close proximity to the building.

The sequence of movement of the sail assemblies 10 and 12 relative to the first vertical axis 4 and the wind direction 60 is illustrated in Figures 5 to 8. In Figure 5, it will be seen that one of the assemblies 10 lies in the plane of the mutually parallel axes 4 and 14, the other assembly 12 being perpendicular to said plane. In Figure 6, both assemblies 10 and 12, while retaining their mutually normal dispositions have moved (in a clockwise direction) around the first vertical axis 4 such that both assemblies are inclined to said plane. Figures 7 and 8 illustrate further positions of the assemblies 10 and 12 during their rotation about the axis 4, it being seen that the assemblies remain at right angles to each other regardless of their dispositions relative to said first vertical axis 4.

With a wind motor according to the invention, the sails can be made of large area, yet narrow enough to fit between buildings if desired so as to make use of "windy" areas of buildings. In addition, a wind motor according to the invention is relatively simple and cheap to install.

In an alternative arrangement of the invention, the axes may be arranged to be horizontal or substantially horizontal, in which case the crosshead assemblies will then rotate in substantially vertical planes.

It will be appreciated that the sails as disclosed, i.e. substantially flat planar members, may be changed to other shapes and/or thicknesses.

Finally, a wind motor according to the invention may include provision for self-modification or manual modification for protection against storm damage.

Claims

1. A wind motor comprising an assembly which is rotatable as a whole about a first axis, said assembly including at least one sail or other wind pressure surface which is rotatable about an axis spaced from and parallel to said first axis, said sail or other wind-pressure surface being mounted between spaced crosshead assemblies between which there is no connection on said first axis, the orientation of said sail or other wind-pressure surface relative to the plane of said axes being controlled, via a chain or gear device from an idler wheel located on said first axis, by a wind vane which follows the instantaneous direction of the wind.

2. A wind motor according to Claim 1, wherein said axes are vertical.

3. A wind motor according to Claim 1 or Claim 2, wherein the movement of the sail or other wind-pressure surface about its axis of rotation is in direction opposite to the direction of rotation of the assembly about said first axis.

4. A wind motor according to any of Claims 1 to 3, wherein the speed of rotation of the said or other wind-pressure surface is less than the speed of rotation of said assembly.

5. A wind motor according to any of Claims 1 to 3, wherein the sail or other wind-pressure surface is mounted in upper and lower crosshead assemblies, the lower crosshead assembly being rigidly connected to a shaft on said first axis of rotation.

6. A wind motor according to Claim 5, wherein said crosshead assemblies consist of open framework.

7. A wind motor according to any of Claims 4 to 6, wherein the sail or other wind-pressure surface carries a sprocket wheel which is connected to an idler wheel via an endless chain or notched belt to provide the rotational speed ratio between the assembly and the sail or wind-pressure surface.

8. A wind motor according to any of Claims 4 to 6, wherein the sail or other wind-pressure surface carries a bevel gear which is connected to an idler wheel via a lay shaft to provide the rotational speed ratio between the assembly and the sail or wind-pressure surface.

9. A wind motor according to Claim 7 or Claim 8, wherein said idler wheel is mounted on said first axis such that said idler wheel may remain static upon rotation of the assembly about said first axis but such that said idler wheel may rotate about said first axis upon movement of the wind vane about said first axis.

10. A wind motor according to any of Claims 1 to 9, wherein the rotatable assembly includes two sails or other wind-pressure surfaces mounted for rotation between upper and lower crosshead assemblies which extend to either side of the first axis, said sails or wind pressure surfaces being connected to an idler wheel through the intermediaries of chains or gear trains.

11. A wind motor according to Claim 10, wherein the sails or other wind-pressure surfaces, irrespective of their dispositions relative to said first axis, are located and remain in substantially normal dispositions relative to each other.

12. A wind motor according to any of Claims 1 to 11, wherein the wind vane consists of a lower part rigidly or semi-rigidly connected to an upper part in order that the vane may follow more effectively the mean direction of the wind which is incident on the assembly.

13. A wind motor constructed and adapted to operate substantially as herein described with reference to and as illustrated in the accompanying drawings.