DEVICE AT A WIND PROPELLER

Abstract: Wind propeller the blades (1) of which are permanently connected to a rotatably mounted hub (2). The invention is characterized in that the blades (1) of the propeller have a radially displaceable disc which, under the influence of a springing means (4) working between the disc (3) and the blade (1) or the hub (2) is kept in a first position relative to the hub (2) as long as the wind propeller remains motionless or rotates slowly. At an increasing rotary speed the disc (3) is successively displaced radially outwards from the hub (2) to a second position relative to the hub (2) by the centrifugal force counteracted by the springing means (4). The blade (1) as well as the disc (3) belonging to it has one or more through openings (5, 6) equally dispersed over the blade (1) and the disc (3) so that when the disc (3) is in the first said position it covers the opening or the openings (5, 6) in the blade (1) and vice versa, that is to say that the blade (1) and the disc (3) create a complete area of action for the wind. When the disc (3) moves towards the second position caused by an increased wind velocity said opening or openings (5, 6) in the blade (1) and the disc (3) increasingly coincide causing the area of action of the blade (1) to successively decrease at an increasing wind velocity.

Description: Device at a wind propeller This invention relates to a device at a wind propeller the blades of which are permanently connected to a rotatably mounted hub. One of the biggest disadvantages with wind propellers of above said type is that the wind propeller's rotary speed is dependent upon the wind velocity. As most types of equipment which can be conceivably driven by a wind propeller demands considerably constant rotary speed, there have been trials to vary the area of action of the wind depending on the wind velocity by varying the banking angle of the blades. It is obvious that such solutions are technically complicated and expensive and are there¬ fore not applicable to wind propellers intended for simple adaptions, for example to supply a recreative cottage with electricity for lighting and perhaps a certain amount of heating. The object of the present invention is to achieve a wind propeller of introductory said type where the area of action successively decreases at an increasing wind velocity and this is made possible in that the blades of the propeller have a radially displaceable disc which under the influence of a springing ..means working between the disc and the blade or the hub is kept in a first position relative to the hub as long as the wind propeller remains motionless or rotates slowly but at an increasing rotary speed is successively displaced radially outwards from the hub to a second position relative to the hub by the centrifugal force counteracted by the springing means and that the blade as well as the disc belonging to it has one or more through-openings equally dispersed over the blade and the disc so that when the disc is in the first said position it covers the opening or the openings in the blade and vice versa, that is to say the blade and the disc create a complete area of action for the wind and so that when the disc moves towards the second position caused by an increased wind velocity, said opening or openings in the blade and the disc increasingly coincides. In the following the invention wiLl be explained further relating to the enclosed drawing where fig 1 schematically shows an embodiment of a wind propeller according to the invention at a low wind velocity. Fig 2 shows the propeller according to fig 1 at a high wind velocity. In the drawing numeral 1 relates to a blade of a wind propeller. The blade is permanently connected to a rotatably mounted hub 2 together with the other blades of the propeller. At the front or the back of the blade a radially displaceable disc 3 is arranged. The disc is connected to the hub 2 or the area of the blade 1 nearest to the hub via a springing means 4, in the simplest adaption a spiral spring. The task of the springing means 4 is to keep the disc in a first position fig 1, as long as the wind propeller remains motionless or rotates slowly. When the rotary speed of the wind propeller increases caused by an increasing wind velocity, the disc 3 is successively displaced outwardly from the hub 2, working against the springing means 4, until the disc has reached a second position, fig 2. The blade 1 as well as the disc 3 has one or more through openings 5 and 6 respectively, in the drawing eight openings. These are equally dispersed both on the blade 1 and the disc 3- When the disc 3 is in its first position the openings are displaced relative to each other so that the openings 6 in the disc 3 are covered by the blade 1 and the openings " 5 In this are covered by "' the disc 3- Thus the blade 1 and the disc 3 form a complete area of action for .the wind. When the disc is successively displaced towards the second position by above said reason, the openings 5, 6 will be covered by the disc 3 to a gradually less extent to finally coincide when the disc 3 is situated in the second position. This means that the effective area of action of the blade 1 successively decreases with an increasing wind velocity. By means of the invention the rotary speed of the wind propeller Is kept constant in a simple way when the wind velocity varies within certain limits.

Claims: Claim Device at a wind propeller the blades 1 ) of which are permanently connected to a rotatably mounted hub (2), c h a r a c t e r i z e d in that the blades (1) of the propeller have a radially displaceable disc (3), which under the influence of a springing means (4) working between the disc (3) and the blade (1 ) or the hub (2) is kept in a first position relative to the hub (2) as long as the wind propeller remains motionless or rotates slowly but at an increasing rotary speed is successively displaced radially outwards from the hub (2) by the centrifugal force % counteracted by the springing means (4) and that the blade (1) as well as the disc (3) belonging to it has one or more through-openings (5, 6) equaLly dispersed over the blade (1) and the disc (3) so that when the disc (3) is in the first said position it covers the opening or the openings (5) in the blade (1) and vice versa, that is to say the blade (1) and the disc (3) create a complete area of action for the wind so that when the disc (3) moves towards the second position caused by an increased wind velocity, said opening or openings (5, 6) in the blade (1) and the disc (3) increasingly coincides. OMPI

Inventors: JILKEN LEIF, JILKEN, LEIF
Applicants: STAONGAOKONSULT I KALMAR HB
Application year: 1983
Main classification: F03D7
IPC codes: F03D7