JP2017227176A - Hydroelectric generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydroelectric generator including a speed-increasing mechanism showing a superior generating efficiency while keeping a high waterproof characteristic.SOLUTION: This invention relates to a magnetic gear type hydroelectric generator constructed in such a way that a low-speed rotor 30, a high-speed rotor 50 and a water turbine 10 are rotatably attached to a central axle 21, a stator 40 having a stator pole 42 is immovably arranged between the low-speed rotor 30 and the high-speed rotor 50, a magneto coil 43 is wound around the stator pole 42 and the low-speed rotor 30 connected to the water turbine 10 is rotated to cause the high-speed rotor 50 to rotate in its increased speed to generate electricity. The stator 40 not rotated is attached to the central axle 21 through an O-ring 14 to form a watertight structure. The rotating low-speed rotor 30 and the water turbine 10 are rotatably attached to the central axle 21 through a slide bearing 22, so that it is possible to provide a hydroelectric generator showing a superior generating efficiency.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hydroelectric generator used by being put into water, and more particularly to a hydroelectric generator having a speed increasing mechanism using a magnetic gear used for small hydroelectric power generation and the like.

Among the hydroelectric generators, there is a small hydroelectric generator as a generator for small-scale applications.
There are various installation forms of small hydroelectric generators, but one simple installation method is to install a generator with a water turbine in an existing waterway, etc., and drive the generator by rotating the turbine to obtain power There is an installation method.

  In waterways where such small installations of small hydropower are installed, the amount of water is small and the flow speed is often slow. For this reason, the rotational speed of the water turbine tends to be low, and a rotation speed increasing mechanism is often required, and the power generation efficiency of the generator needs to be improved as much as possible.

As a hydroelectric power generation apparatus in which a decrease in power generation efficiency is suppressed, Patent Document 1 has a spiral blade 930 provided on the outer periphery as shown in FIG. The hollow shaft body 931 that rotates by the water flow, the frame member 950 that is provided so as to surround the spiral blade 930, and the center shaft of the hollow shaft body 931 extend so as to be unrotatable to the frame member 950. A fixed shaft 920 that is fixed and a rotating shaft 921 that extends so as to overlap the central axis and that is rotatably supported by the frame member 950 are provided. The hollow shaft body 931 rotates on the fixed shaft 920. A spiral water wheel is presented which is supported in a possible manner and is fixed to a rotating shaft 921.
According to Patent Document 1, when the spiral water wheel is configured in this manner, the hollow shaft body 931 is provided so as to be rotatable with respect to the frame member 950 with the fixed shaft 920 and the rotating shaft 921 as rotation centers. A connecting portion between the body 931 and the fixed shaft 920 can be provided at one place. Thereby, since the number of sliding members such as the bearing 964 and the oil seal 966 disposed between the inside and the outside of the hollow portion of the hollow shaft body 931 can be reduced, the hollow shaft via the oil seal 966 and the like can be reduced. Without increasing the frictional torque between the body 931 and the fixed shaft 920, the waterproofness of the hollow portion of the hollow shaft 931 can be enhanced. In other words, the spiral water wheel having the above-described configuration has high waterproofness and suppresses a decrease in rotational efficiency.
However, in the structure as in Patent Document 1, the number of sliding members can be reduced. However, at one place, the rotating portion needs to be waterproofed by a sliding member such as an oil seal.

In a waterproof structure with sliding members such as an oil seal, measures such as increasing the tension of the oil seal or double the oil seal are required to obtain reliable waterproof properties. Resistance increased and power generation efficiency decreased.
However, especially for generators used in waterways with low water volumes and slow flow rates, the problem is that while maintaining high waterproof properties, it is necessary to suppress the decrease in efficiency and improve the generator's power generation efficiency as much as possible. was there.

JP 2016-50554 A

  The present invention has been made in view of the above problems, and relates to a hydroelectric generator having a speed increasing mechanism used for small hydropower generation and the like, and to provide a hydroelectric generator having high power generation efficiency while maintaining high waterproof characteristics. For the purpose.

In order to achieve the above object, the invention according to claim 1 of the hydroelectric generator of the present invention comprises:
A central axis that does not rotate around the axis, a low-speed rotor, a stator, and a high-speed rotor that are coaxially mounted on the central axis;
The low-speed rotor having a large number of pole pairs and the high-speed rotor having a small number of pole pairs are rotatably attached to the central axis;
The stator having the number of pole pairs of the low-speed rotor and the number of pole pairs of the high-speed rotor, or the stator pole between the low-speed rotor and the high-speed rotor and the stator pole between the low-speed rotor magnet and the high-speed rotor. Non-rotatably attached to the central shaft so as to face the rotor magnet,
In a magnetic gear type hydroelectric generator in which a power generation coil is wound around the stator pole and the high speed rotor rotates at an increased speed by driving the low speed rotor,
The inside of the stator has a watertight structure and is attached to the central shaft via an O-ring, and the low-speed rotor is attached to the central shaft via a sliding bearing.
In the present invention, the stator attached to the central shaft via the O-ring and having a watertight structure on the inner side is non-rotatably attached to the central shaft, and even if the O-ring is tightened to increase water tightness, the low-speed rotor and the high-speed Since the rotation of the rotor is not hindered, a decrease in power generation efficiency can be suppressed. Further, in the present invention, since the low-speed rotor that rotates while being wetted is structured to be rotatably attached to the central shaft via the slide bearing, when the low-speed rotor is wetted, the water that has entered the gap between the slide bearing and the central shaft The lubrication action reduces the rotational resistance of the sliding bearing, further reducing the reduction in power generation efficiency, and can provide a hydroelectric generator with good power generation efficiency.

Further, the invention according to claim 2 of the present invention is characterized in that the low-speed rotor is fixed to a turbine, and the turbine is attached to the central shaft via a slide bearing. It is a generator.
In the present invention, the low-speed rotor and the water turbine are integrated, and the two low-speed rotors are attached to the central shaft so that the low-speed rotor is attached to the central shaft. The vibration during rotation can be reduced, and the operation of the generator can be more stable, and a more reliable hydroelectric generator can be provided.

The invention according to claim 3 of the present invention is the hydraulic power generator according to claim 2, characterized in that the water turbine is attached to the mandrel via the two sliding bearings.
In the present invention, since the water turbine is rotatably held by two bearings having a wide interval, it is possible to reduce the vibration of the water turbine, to further improve the operation of the generator, and to provide a more reliable hydroelectric generator. can do.

  In the hydroelectric generator of the present invention, the stator that is non-rotatably attached to the central shaft and has a watertight structure on the inside is attached to the central shaft via an O-ring, and a low-speed rotor that rotates while being submerged is centered via a sliding bearing. Since the structure is attached so as to be rotatable on the shaft, the rotation of the rotor is not hindered by the O-ring, so that it is possible to provide a hydroelectric generator with good power generation efficiency without reducing power generation efficiency.

It is a fragmentary sectional perspective view which shows the structure of the 1st Example of this invention. It is a double view which shows the external appearance of a present Example. It is sectional drawing which shows the structure of a present Example. It is a figure which shows the waterproof structure of the generator by the conventional spiral water wheel.

Hereinafter, with reference to FIGS. 1-3, the 1st Example of the hydroelectric generator which concerns on this invention is described in detail.
First, the external appearance and schematic structure of the hydroelectric generator of the present embodiment will be described with reference to FIGS. FIG. 2 is a two-side view of the present embodiment, and FIG. 3 is a central sectional view.

  As shown in FIG. 2, the hydroelectric generator 100 of the present embodiment includes a water turbine 10 having a plurality of water turbine blades 11 on the circumference, and a central shaft 21 protruding from the water turbine 10, as shown in FIG. 3. The water turbine 10 has a power generation mechanism 90 inside. The hydroelectric generator 100 according to the present embodiment is installed so that the central axis protruding side is on the downstream side of the water flow.

  The central shaft 21 is a hollow rod that holds the hydroelectric generator 100. As shown in FIG. 3, both ends are sealed with end caps 25, and two wiring holes 21a for passing the power generation output wire 72 are provided. .

  The hydroelectric generator 100 has a front cover 12 having a substantially conical end and an opening at the other end and a plurality of turbine blades 11 provided in the circumferential direction, and a substantially cylindrical tail having a substantially truncated cone shape and a bottom portion on one side. The outer shape is formed by the water wheel 10 including the cover 13, and the water wheel 10 is rotatably attached to the central shaft 21 via two sliding bearings 22.

  Inside the water turbine 10, a power generation mechanism 90 including a low-speed rotor 30, a stator 40, and a high-speed rotor 50 that are coaxially attached to the central shaft 21 is accommodated. The outermost low-speed rotor 30 is rotatably attached to the central shaft 21, is connected to the water turbine 10, and rotates together with the water turbine 10.

  The stator 40 is located inside the low-speed rotor 30 and is non-rotatably attached to the central shaft 21, and the high-speed rotor 50 is rotatably attached to the central shaft 21 on the innermost periphery.

  The power generation output electric wire 72 from the power generation mechanism 90 is inserted into the hollow portion of the central shaft 21 from one of the two wiring holes 21a of the central shaft 21, and is taken out of the central shaft 21 from the other wiring hole 21a. It is wired in the machine holding structure.

  Hereinafter, the structure of the hydroelectric generator 100 will be described with reference to FIG. FIG. 1 is a partial cross-sectional perspective view showing the configuration of this embodiment.

The front cover 12 is a shell-shaped part having a substantially conical tip, and has an intermediate wall 12a inside, and a bearing mounting hole is provided at the center of the intermediate wall 12a. Further, a plurality of turbine blades 11 are provided in the maximum diameter portion near the rear end opening, the opening has a connecting portion with the tail cover 13, and the rotor mounting wall for connecting the low speed rotor 30 in the vicinity of the connecting portion. 12b.
The tail cover 13 is a shell-shaped part having a substantially conical shape with a bottom, a bearing mounting hole is provided at the center of the bottom, and a connection portion with the front cover 12 is provided on the opening side.

  The front cover 12 and the tail cover 13 are connected to each other at the connecting portion to form an integrated water wheel 10, and the bearing mounting hole in the intermediate wall 12 a of the front cover 12 near the front end side of the axial length and the tail at the rear end of the axial length. A slide bearing 22 is incorporated in each of the bearing mounting holes in the center of the bottom portion of the cover 13, and the water turbine 10 is rotatably held on the central shaft 21 by the two slide bearings 22.

  In the hydroelectric generator of the present embodiment, the turbine blades 11 are disposed between the two sliding bearings 22 provided at a distance close to both ends in the axial direction of the turbine 10. The turbine 10 can stably operate even when a rotational force is applied to the turbine 11 by a water flow or the like and the water turbine receives a force in the axial direction or a direction perpendicular to the axial direction by the water flow or the like.

Further, in the hydroelectric generator of the present embodiment, the bearing that rotatably holds the water turbine 10 is a sliding bearing.
In the sliding bearing, the shaft rotates smoothly in the bearing due to a slight gap between the inner diameter and the shaft diameter of the bearing. Therefore, when sliding bearings are used in water, the water in the surrounding environment enters the gap between the inner diameter of the bearing and the water that has entered between the inner diameter of the bearing is lubricated in the same way as the oil in the oil-impregnated bearing. Shows the effect. Thereby, since the rotational resistance of a slide bearing falls, the fall of power generation efficiency is further suppressed and the hydroelectric generator with sufficient power generation efficiency can be provided.

Of the power generation mechanism 90 (see FIG. 3) housed in the water turbine 10, the outermost low-speed rotor 30 is a bottomed cylindrical rotor case 31 and a soft softened to the inside of the cylindrical portion of the rotor case 31. A substantially cylindrical back yoke 32 made of a magnetic material, and magnetized in the radial direction, are fixed at equal intervals on the inner peripheral side of the back yoke 32 so that the pole directions of adjacent magnets are opposite to each other. The magnet 33 has a plurality of magnetic pole pairs.
The rotor case 31 has a bearing mounting hole in which the slide bearing 22 is incorporated at the center of the bottom, and a flange portion 31a for fixing the rotor case 31 to the rotor mounting wall 12b of the front cover 12 at the opening end. The low speed rotor 30 is fixed to the water turbine 10 by fixing the flange portion 31a to the rotor mounting wall 12b of the front cover 12, and when the water turbine 10 is rotated by the water flow, the low speed rotor 30 is also rotated.

  The rotor case 31 is rotatably held on the central shaft 21 by the sliding bearing 22, and the degree of coaxiality between the rotor case 31 and the central shaft 21 is only shifted by a gap between the inner diameter of the bearing and the shaft diameter. However, since the outer diameter of the rotor case 31 is much larger than the length of the sliding bearing 22, the sliding of the rotor case 31 cannot be suppressed only by the sliding bearing 22 incorporated in the center of the bottom of the rotor case 31.

  In the hydroelectric generator of this embodiment, the rotor case 31 that is rotatably held on the central shaft 21 by the slide bearing 22 is fixed to the water turbine 10 that is also rotatably held on the central shaft 21 by the slide bearing 22. The fixed locations were the rotor mounting wall 12b of the front cover 12 and the flange portion 31a of the rotor case 31 near the maximum diameter portion of the water turbine 10. Thereby, since the rotor case 31 and the front cover 12 are closely connected in the vicinity of the maximum diameter portion of the water turbine 10, there is no possibility that both the rotor case 31 and the front cover 12 fall down, and there is no vibration with respect to the central shaft 21. A stable rotating operation can be realized, and a more reliable hydroelectric generator can be provided.

  The stator 40 includes a pole holder 41, a plurality of stator poles 42, a plurality of power generation coils 43, and a holder plate 44, and accommodates the wiring board 45 inside the stator 40 as necessary.

  The pole holder 41 is made of a non-magnetic material and has a bottomed cylindrical shape. A hole for receiving the central shaft 21 is provided in the center of the bottom, and a central cylindrical portion 41a having an inner diameter extending from the hole extends to the opening side. The inner cylinder portion 41a has a groove portion in which the O-ring 14 is incorporated.

  A holder plate 44 is attached to the opening of the pole holder 41. The holder plate 44 is substantially disk-shaped, and a hole into which the central shaft 21 enters is provided at the center. A cylindrical shape with the hole as an inner diameter extends, and a groove portion in which the O-ring 14 is incorporated is formed in the cylindrical inner diameter portion. Have.

  With the stator pole 42 being press-fitted into the pole holder 41 and the holder plate 44 being attached to the opening, the inner cylindrical portion 41a of the pole holder 41 and the cylindrical inner cylindrical portion of the holder plate 44 are filled with O. When each of the rings 14 is incorporated and the central shaft 21 is inserted, the bottom of the pole holder 41, the cylindrical portion of the pole holder 41 into which the stator pole 42 is press-fitted, and the holder plate 44 serve as a partition wall and are surrounded by the pole holder 41 and the holder plate 44. The area to be welded, that is, the inside of the stator 40 is in a watertight state.

Since the stator 40 is non-rotatably attached to the central shaft 21, in order to ensure the watertight state of the stator 40, for example, the tightening force of the O-ring 14 is increased or the O-ring 14 is doubled. However, there is no influence such as obstructing the movement of the low-speed rotor 30 that rotates with the water turbine 10.
Thereby, in the hydroelectric generator of the present embodiment, the hydroelectric generator 10 with good power generation efficiency can be provided without obstructing the rotation operation of the water turbine 10 even if the inner side of the stator 40 is in a reliable watertight state.

  A high-speed rotor 50 is further accommodated inside the stator 40. The high-speed rotor 50 includes a substantially cylindrical rotor wheel 51, a substantially cylindrical back yoke 52 made of a soft magnetic material attached to the outer periphery of the rotor wheel 51, and a magnet that is magnetized in the radial direction so that adjacent magnets There are a plurality of magnets 53 of magnetic pole pairs fixed at equal intervals on the outer peripheral side of the back yoke 52 so that the polar directions are opposite to each other. The rotor wheel 51 is rotatably attached to the pole holder 41 of the stator 40 via a bearing attached to the inner diameter portion. As a result, the high-speed rotor 50 can rotate with respect to the central shaft 21.

  As described above, the stator 40 is fixed to the central shaft 21, has a plurality of stator poles 42, the holder plate 44 is attached to the opening, and the inner side is watertight by the O-ring 14. A low-speed rotor 30 having a magnet 33 of a magnetic pole pair is rotatably attached to the central shaft 21, and a generator coil 43 attached to a stator pole 42 is provided inside a stator 40 having a watertight structure, and a wiring board as required. 45 is accommodated, and a high-speed rotor 50 having a plurality of magnets 53 of magnetic pole pairs is rotatably attached to the central shaft 21 to constitute hydraulic power generation having a speed increasing mechanism using a magnetic gear.

In the hydroelectric generator of the present embodiment having the above-described configuration, an electrical component that may be damaged due to flooding, that is, a power generation coil 43 and a wiring board 45 to be used as necessary, are sealed by an O-ring 14. Since it is accommodated inside 40, a hydroelectric generator that can be used without any problem even when thrown into water can be provided.
In addition, since the high-speed rotor 50 that rotates at a high speed by the speed increasing mechanism using the magnetic gear is accommodated inside the stator 40, the resistance that the high-speed rotor 50 receives during rotation can be kept low, and a hydroelectric generator with good power generation efficiency can be provided.

  INDUSTRIAL APPLICABILITY The present invention can be used for various types of hydroelectric generators that are used by throwing them into a water channel with a low flow rate where the generator may be submerged or flooded. It becomes.

  It should be noted that the present invention is not limited to the matters described in the above embodiments, and includes various modifications and corrections that can be conceived by those having ordinary knowledge in the field of the present invention. Needless to say, even if there is a design change within a range that does not deviate from the above, it is included in the present invention.

DESCRIPTION OF SYMBOLS 10 Water wheel 11 Water wheel 12 Front cover 12a Intermediate wall 12b Rotor mounting wall 13 Tail cover 14 O-ring 21 Center shaft 21a Wiring hole 22 Sliding bearing 25 End cap 30 Low speed rotor 31 Rotor case 31a Flange part 32 Back yoke 33 Magnet 40 Stator 41 Pole holder 41a Central cylindrical portion 42 Stator pole 43 Power generation coil 44 Holder plate 45 Wiring board 50 High speed rotor 51 Rotor wheel 52 Back yoke 53 Magnet 72 Power generation output wire 90 Power generation mechanism 100 Hydroelectric generator 920 Fixed shaft 921 Rotating shaft 930 Spiral blade 931 Hollow shaft body 950 Frame member 964 Bearing 966 Oil seal

Claims (3)

A central axis that does not rotate around the axis, a low-speed rotor, a stator, and a high-speed rotor that are coaxially mounted on the central axis;
The low-speed rotor having a large number of pole pairs and the high-speed rotor having a small number of pole pairs are rotatably attached to the central axis;
The stator having the number of pole pairs of the low-speed rotor and the number of pole pairs of the high-speed rotor, or the stator pole between the low-speed rotor and the high-speed rotor and the stator pole between the low-speed rotor magnet and the high-speed rotor. Non-rotatably attached to the central shaft so as to face the rotor magnet,
In a magnetic gear type hydroelectric generator in which a power generation coil is wound around the stator pole and the high speed rotor rotates at an increased speed by driving the low speed rotor,
A hydroelectric generator characterized in that the inside of the stator has a watertight structure and is attached to the central shaft via an O-ring, and the low-speed rotor is attached to the central shaft via a sliding bearing.   The hydroelectric generator according to claim 1, wherein the low-speed rotor is fixed to a water turbine, and the water turbine is attached to the central shaft via a sliding bearing.   The hydroelectric generator according to claim 2, wherein the water turbine is attached to the central shaft via the two sliding bearings.