Water wheel impeller blade type electric power generating apparatus

A water wheel impeller blade type electric power generating apparatus including a rotating shaft for transmitting motive power to a power generator, a rotor fixed to the rotating shaft, an impeller blade provided on the outer periphery of the rotor to receive a flow of fluid for rotating the rotor, and a fluid guide plate inclined from above to below the rotor so as to guide the fluid to the impeller blades located on a lower portion of the rotor. The impeller blade is rotatably disposed on the rotor, a fluid receiving part and a stopper part shorter than the fluid receiving part are formed, the fluid receiving part is disposed in the upstream direction of the fluid in a fluid passage, and a bearing which rotatably supports the rotating shaft is provided on the outer periphery of the rotor.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a water wheel impeller blade type electric power generating apparatus using a water stream, a sea water current or the like in, for example, a river or the sea to generate hydroelectric power.

2. Field of the Related Art

As the water wheel impeller blade type electric power generating apparatus, Patent Document 1 can be cited. This structure includes a rotating shaft for transmitting motive power to the power generator, a rotor fixed to this rotating shaft, and impeller blades which are provided on the outer periphery of this rotor for rotating the rotor by receiving a flow of fluid, and the rotating shaft is rotatably supported by a side plate of an apparatus frame body through a bearing. The impeller blades have a fluid receiving part disposed rotatably on the rotor and a stopper part shorter than this fluid receiving part, being formed in the shape of a letter L and disposed such that the fluid receiving part is on the side receiving a fluid pressure of the fluid passage and the stopper part maintains erection of the fluid receiving part.

Since the rotating shaft is rotatably supported by the side plate of the apparatus frame body through the bearing, weights of the rotor and the large number of impeller blades and the like provided on the rotor are applied to the bearing. Moreover, since the apparatus is installed in the water or seawater, the apparatus is made of a stainless material. That causes no problem if the rotor is small-sized, but if a rotating drum of the rotor has a diameter of approximately I in and a width of approximately 1.8 m and a length of the fluid receiving part of the impeller blade is approximately 0.4 m, for example, the weights of the rotor and the impeller blades are approximately 450 Kg, and this weight is applied to the bearing through the rotating shaft. Since a heavy load is applied to the bearing as above, there has been a problem that the life of the bearing is short.

An object of the present invention is to provide a water wheel impeller blade type electric power generating apparatus which can alleviate a burden on the bearing which supports the rotor, the impeller blades and the like and prolong the life of the bearing.

SUMMARY OF THE INVENTION

In order to solve the above problems, according to the invention as stated in claim1, there can be provided a water wheel impeller blade type electric power generating apparatus comprising: a rotating shaft for transmitting motive power to a power generator; a rotor fixed to this rotating shaft, and an impeller blade provided on the outer periphery of this rotor to receive a flow of fluid for rotating the rotor, characterized in that a fluid guide plate inclined from above to below the rotor so as to guide the fluid to the impeller blades located on a lower portion of the rotor is provided, the impeller blade is rotatably disposed on the rotor, a fluid receiving part and a stopper part shorter than this fluid receiving part are farmed in the shape of a letter L, the fluid receiving part is disposed in the upstream direction of the fluid in the fluid passage, an impeller blade passage frame body is provided to surround the rotor without impeding rotation of the impeller blades on the outer periphery of the rotor, and a scaled hollow frame body in which a sealed gas chamber by sealing a gas inside is formed is fixed to the rotating shaft in the rotor.

Advantageous Effects of the Invention

By forming the sealed gas chamber in which the gas is sealed inside the rotor, a buoyancy force is generated by this sealed gas chamber, and the load caused by the weights of the rotor and the impeller blades and the like provided on the rotor applied to a bearing can be alleviated. The volume of the sealed gas chamber is preferably set to the volume that can obtain the buoyancy force matching the weight of the rotor and the weights of the impeller blades and the like provided on the rotor, but that is not limiting.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

This embodiment was obtained by improving Japanese Patent Application No. 2010-170678 by the applicant of the present invention. Thus, the configuration of the application will be described first, and then, a configuration characterizing the invention of this application will be described.

As illustrated inFIGS. 3 and 4, a rotor1includes a drum body2which has an outer periphery formed in the shape of a dodecahedron and a side plate3which is fixed to each of both sides of this drum body2, the outside diameter of the side plate3being larger than that of the drum body2, The side plate3is fixed to a rotating shaft4by means of a fixing member5. In the portion, which is projected upward from the drum body2of the side plate3, a bearing6is fixed in twelve places corresponding to the respective sides of the dodecahedron.

To the rotor1, an impeller blade10as shown inFIG. 5is mounted. The impeller blade10is comprised of a stopper part11with a short length and a fluid receiving part12, which arises from this stopper part11, and the fluid receiving part12is disposed on the fluid upstream side. A support shaft13of the impeller blade10is fixed by a fixing member14, and the both end parts of the support shaft13are rotatably supported by means of the bearings6which are disposed oppositely to each other. The fluid receiving surface side of the fluid receiving part12is concaved in the shape of a circular arc such that it can receive a large volume of fluid when the fluid receiving part12is erected with the stopper part11being butted against the drum body2of the rotor1. As illustrated inFIG. 1, the fluid receiving part12is provided with a length large enough to cover the stopper part11and the lower portion of the fluid receiving part12of the impeller blade10given on the thrust down side when the impeller blade10is thrust down.

As illustrated inFIGS. 1 and 2, the rotating shaft4of the rotor1to which the impeller blades10are mounted is rotatably supported by means of a side plate21which is fixed on both sides of a bottom plate20through a bearing22. On both side plates21, a top plate23is fixed. In other words, the bottom plate20, side plates21and top plate23constitute a frame body of the apparatus. To the front-end part of the top plate23, a fluid guide plate24is fixed with inward inclination. Herein, the fluid guide plate24is provided with a length and inclination angle large enough to guide the fluid flowing in a direction A to the impeller blades10positioned under the rotating shaft4.

Above the top plate23, a power generator30is fixed such that an input shaft31of the power generator30is in parallel with the rotating shaft4. To one end part of the rotating shaft4and the input shaft31, gears32,33are fixed, respectively, and a chain34is extended between the gears32,33.

Next, the function of the apparatus will be described. Once the apparatus is fixed at a predetermined position underwater or undersea such that the fluid guide plate24faces the flowing direction A of the fluid flow, the fluid guided by the fluid guide plate24and the fluid flowing under the fluid guide plate24are butted against the fluid receiving part12of the impeller blades10(101to105) positioned under, the rotating shaft4, resulting in the rotor1and the rotating shaft4being rotated in the direction of arrow B. The rotation of the rotating shaft4is transmitted to the input shaft31through the gears32,33and the chain34, thereby the power generator30generates electric power.

The fluid receiving part12is longer and heavier than the stopper part11, and thus, the impeller blades10(107to112) positioned above the rotating shaft4are naturally thrust down by their own weight. In other words, when the impeller blade10is thrust down, the fluid receiving area for receiving the fluid of the impeller blade10is substantially reduced, whereby, on the backward motion side, the resistance of the impeller blade10to the fluid is reduced. In addition, when the impeller blade10is thrust down, the fluid receiving part12covers the stopper part11and the lower portion of the fluid receiving part12of the subsequent impeller blade10, being butted against the stopper part11thereof. This also reduces the resistance of the impeller blade10to the fluid on the backward motion side.

In addition to the above-mentioned advantageous effects, the present apparatus exerts the following ones. The fluid guide plate24will cause the fluid to flow under the rotor1, whereby the mud, sand, dirt and the like in the river will not be collected into the water wheel (including the rotor1and the impeller blades10). In addition, the rotor1is constituted by components having simple geometries, and further, the stopper part11and the fluid receiving part12can be manufactured as an integral part, and thus, the apparatus allows a substantial reduction in a manufacturing cost.

Next, the configuration of the invention of this application will be described. In this embodiment, a sealed hollow frame body41having a cylindrical shape and made of a stainless material so as to form a sealed gas chamber40is fixed to the rotating shaft4inside the rotor1constituted by the drum body2and the both side plates3and3. Air is sealed inside the sealed gas chamber40or a gas with large buoyancy force such as nitrogen gas, carbon oxide gas or the like is sealed therein.

By forming the sealed gas chamber40in which the gas is sealed inside the rotor1as described above, a buoyancy force is generated by this sealed gas chamber40, and the load caused by the weights of the rotor1and the impeller blades10and the like provided on the rotor1applied to a bearing22can be alleviated. The volume of the sealed gas chamber40is preferably set to the volume that can obtain the buoyancy force matching the weight of the rotor1and the weights of the impeller blades10and the like provided on the rotor1. If the weight of the rotor1and the impeller blades10and the like provided on the rotor1is 450 Kg, for example, the volume is set to approximately 0.45 m3(the cube of 0.45 in). However, in this embodiment, it is not necessary to match the load applied to the bearing22with the buoyancy force of the sealed gas chamber40. That is, it is only necessary to reduce the load applied to the bearing22.

In each of above-mentioned embodiments, the drum body2is formed in the shape of a dodecahedron and12impeller blades10are provided, but the number of the impeller blades10is not limited. Moreover, the drum body2does not have to have a square shape but may have a circular shape.