GB2097481A

GB2097481A - Wind or water-powered rotor blade

Info

Publication number: GB2097481A
Application number: GB8211209A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-04-25
Filing date: 1982-04-19
Publication date: 1982-11-03
Also published as: GB2097481B

Abstract

The blade comprises a plane square or rectangular vane, symmetrically rotatable about a central vertical axis coincident with the plane of the vane, each side edge incorporating a single flange 11, bent back at an acute angle to the vane surface in such a way that each flange projects on opposing faces of the vane. <IMAGE>

Description

SPECIFICATION Wind or water-powered rotor blade This invention relates to a vertical axis rotor blade, which rotates when acted upon by wind or moving water.

In accordance with the invention a water or wind-powered rotor blade comprises a plane square or rectangular vane, symmetrically rotatable about a central vertical axis coincident with the plane of the vane and from each side edge the vane incorporates a single flange, which is bent back at an acute angle to the vane surface in such a way that each flange projects on opposing faces of the vane.

The aforementioned configuration of the rotor blade when seen as a cross-section perpendicular to the axis of rotation approximates to the shape of the letter 'Z' or alternatively to the mirror image of the letter 'Z'.

Preferably the vane is made to a sufficient thickness to house an internal shaft, which is rigidly located within the vane. Depending on the relative dimensions of the rotor blade; differing methods may be used for mounting the blade.

When the width of the rotor blade is greater than the height, the shaft may project from the lower end of the blade only and be mounted in bearings.

When the height of the rotor blade is greater than the width, the internally located shaft may project from both upper and lower ends of the blade and be mounted in bearings at each end.

In all cases it is preferable to enclose both upper and lower end sections by means of specially shaped gussets which add strength by joining the flange to the face of the vane. When the 'Z' section is made of a single skin the enclosed end section of the blade provides a location for a coaxially mounted flange socket used as an alternative method of securing the rotor blade to a shaft.

An additional embodiment of the invention is included, namely a rotor blade of solid construction incorporating either an integrally made shaft or alternatively a shaft attachment.

Four separate embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which Figure 1 is a side view of the first embodiment; Figure 2 is a cross-sectional view as seen from the plane indicated by the line 2-2 in Figure 1; Figure 3 is a side view of internal shaft assembly (reference second and third embodiments); Figure 4 is a cross-sectional view as seen from the plane indicated by the line 44 in Figure 3; Figure 5 is a side view of the second embodiment; Figure 6 is a cross-sectional view as seen from the line 6-6 in Figure 5; Figure 7 is a side view of the third embodiment; Figure 8 is a cross-sectional view as seen from the plane indicated by the line 8-8 in Figure 7;; Figure 9 is a cross-sectional side view of the fourth embodiment seen from the plane indicated by the line 9-9 in Figure 10; Figure 10 is a cross-sectional view as seen from the plane indicated by the line 10-10 in Figure 9.

The first embodiment of the rotor blade shown in Figures 1 s 2 comprises a vane with flanges 11 made as one piece. Two flanged triangular gussets 12 enclose the upper end section while two flanged triangular gussets 1 3 enclose the lower end section as shown in Figure 2. Gussets 13 provide a base for the coaxial mounting of flanged socket 14, which provides a means of securing the rotor blade assembly to a shaft.

Flanged socket 14 incorporates a grub screw and keyway.

The aforementioned components and those mentioned hereinafter are joined together by rivetting, welding or other suitable means.

Figures 3 8 4 show details of the construction of an internally mounted shaft assembly relating to the second and third embodiments of the invention. Component 17 is a circular section shaft with flats milled on opposing sides of the shaft so as to form a close fit within box member 15, which has a rectangular cross-section as shown in Figure 4. The reduced dimension of the shaft exactly spans the narrowest internal dimension of the box section and the shaft is pinned centrally within the box member by means of counter-sunk rivets. A close fitting rectangular collar 16 is rigidly attached at the extremity of the box member, where the shaft connects.

The second embodiment of the rotor blade is made from twin skins as illustrated in Figures 5 s 6. In the region of the central vane the twin skins 18 are separated by four channel section spacers 19 as shown in Figure 6. The spacers are placed symmetrically with respect to the central axis and the inner spacers in conjunction with the twin skins 18 provide a lodging place for the shaft assembly. In the vertical plane and shaft assembly is rigidly secured between collar 1 6 and capping plate 20, which is fastened by a bolt threaded axially into the end of shaft 17. The end sections of the rotor blade are enclosed by gussets 28, which join the flanges to the vane surface.

Provision may also be made for covering in the hollow end space of the central vane.

The third embodiment of the rotor blade is also made from twin skins as illustrated in Figures 7 8 8. In the region of the central vane the twin skins 21 are separated by two solid spacers 22. Shaft 24 incorporates collar 23 and the extension of the shaft which enters the rotor blade has a rectangular cross-section, which fills the cavity formed by the two skins 21 and spacers 22.

Separate identical shafts are inserted independently from opposite ends of the rotor blade and are secured by countersunk screws, which penetrate skin 21 and are threaded into the rectangular sectional spigot of shafts 24. Gussets 29 enclose the end sections of the rotor blade and if required additional gussets may also be positioned between flange and vane at intervals along the length of the blade. Provision may also be made for covering in the hollow end space of the central vane.

The fourth embodiment of the rotor blade is illustrated in Figures 9 s 10. The central vane and flanges 25 are made to the required shape and thickness as illustrated in Figure 10 by manufacturing the rotor blade in solid form. The shaft may be made integrally as one piece with the solid formed rotor blade or alternatively the shaft may be attached to the rotor blade as a separate component as illustrated by way of example in Figures 9 8 10. It can be seen that the shaft 26 carries a rectangular cross-piece having a width equal to the thickness of the vane. At each end of the cross-piece is a hole for setscrew 27.

Mounted on the cross-piece perpendicular and centrally between the holes is a rectangular fin, which fits exactly into a corresponding recess formed in the rotor blade. The shaft unit 26 is secured in position by setscrews 27, which are threaded into the body of the rotor blade.

The four embodiments of the invention described in this specification are only presented by way of example and numerous changes in the details of'construction and the combination and arrangement of parts may be resorted to without departing from the scope of the invention as hereinafter claimed.

Claims

1. A water or wind-powered rotor blade comprising a plane square or rectangular vane symmetrically rotatable about a central vertical axis coiricident with the plane of the vane and from each side edge the vane incorporates a single flange, which is bent back at an acute angle to the vane surface in such a way that each flange projects on opposing faces of the vane.

2. A water or wind-powered rotor blade according to claim 1 wherein the central vane is of sandwich construction with interior space sufficient to rigidly locate an internal shaft coaxial with the axis of rotation.

3. A water or wind-powered rotor blade according to claims 1 to 2 wherein the axial shaft projects from either the upper or lower end of the rotor blade only so that the extended shaft may be mounted in bearings.

4. A water or wind-powered rotor blade according to claims 1 or 2 wherein the axial shaft projects from both upper and lower ends of the rotor blade so that the respective extensions of the shaft may be mounted in bearings.

5. A water or wind-powered rotor blade according to any of claims 1-3 wherein each end section of the rotor blade is enclosed by means of gussets, which connect the flanges to the vane surface.

6. A water or wind-powered rotor blade according to any of claims 1,2 or 4 wherein the end section of the rotor blade is enclosed by means of gussets, which connect the flanges to the vane surface and wherein additional gussets may be incorporated at intervals along the length of the flange.

7. A water or wind-powered rotor blade according to claim 1 wherein the central vane and flanges are constructed of a single thickness with upper and lower end sections enclosed by means of triangular gussets or end plates, which provide a location for a coaxially mounted flanged socket which is secured to either the upper or lower end section singly or to both end sections jointly; thus providing an alternative method of joining the rotor blade to a shaft or shafts.

8. A water or wind-powered rotor blade according to claim 1 wherein the central vane and flanges are formed to the required shape and thickness by manufacturing the rotor blade in solid form with provision for an axial shaft connection at either end of the rotor blade or alternatively at both ends of the rotor blade.

9. Water or wind-powered rotor blades constructed and arranged substantially as hereinbefore described and shown by way of example in the accompanying drawings.