Hydroelectric power generation equipment
The hydroelectric power generation device addresses gear fretting by using a decoupling shaft coupling to prevent vibration transmission, enhancing gear durability and reducing maintenance.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- NTN CORP
- Filing Date
- 2021-01-15
- Publication Date
- 2026-05-13
AI Technical Summary
Hydroelectric power generation devices experience fretting between gears in the reduction gear due to vibrations transmitted from the water turbine, which can lead to gear wear and reduced lifespan.
The device incorporates a shaft coupling with a first and second flange and a pin arrangement that allows the rotating beam and output shaft to decouple during certain states, preventing the transmission of vibrations to the output shaft and reducing gear contact.
The solution effectively suppresses fretting between gears, thereby extending the lifespan of the reduction gear and reducing maintenance needs.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to a hydraulic power generation device.
Background Art
[0002] The hydraulic power generation device described in Japanese Patent Application Laid-Open No. 2015-14219 (Patent Document 1) is installed in a water channel. The hydraulic power generation device described in Patent Document 1 has a hydraulic power generation module including a waterwheel. In the hydraulic power generation device described in Patent Document 1, for example, using a pulley and a weight, it is possible to switch between a state where the waterwheel is in the water flowing through the water channel and a state where the waterwheel is lifted from the water flowing through the water channel.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] As a method for switching between a state where the waterwheel is in the water flowing through the water channel and a state where the waterwheel is lifted from the water flowing through the water channel, in addition to the above, the hydraulic power generation module is attached to a rotating beam connected to the output shaft of a speed reducer, and the rotation of the input shaft of the speed reducer is transmitted to the output shaft of the speed reducer to rotate the rotating beam, thereby switching between a state where the waterwheel is in the water flowing through the water channel and a state where the waterwheel is lifted from the water flowing through the water channel.
[0005] In hydroelectric power generation modules, vibrations are caused by contact between the turbine and the water flowing through the channel, and these vibrations can be transmitted to the output shaft of the reduction gear via the rotating beam. If the amplitude of these vibrations exceeds the amount of backlash of the gears in the reduction gear, fretting occurs between the gears in the reduction gear. Here, the amount of backlash of the gears refers to the size of the gap between the teeth of gears that mesh with each other. Fretting refers to the phenomenon in which the surfaces of the teeth of gears that mesh with each other wear down due to minute vibrations.
[0006] This invention provides a hydroelectric power generation device capable of suppressing fretting between gears included in a reduction gear. [Means for solving the problem]
[0007] The hydroelectric power generation device of the present invention is arranged in a waterway. The hydroelectric power generation device comprises a rotating beam, a hydroelectric power generation module having a water turbine, a reduction gear having an input shaft and an output shaft, and a shaft coupling. The rotating beam is supported so as to be rotatable around its central axis. The hydroelectric power generation module is attached to the rotating beam. By rotating the rotating beam, the device switches between a first state in which the water turbine is submerged in water flowing through the waterway and a second state in which the water turbine is lifted out of the water flowing through the waterway. The reduction gear reduces the rotation of the input shaft and transmits it to the output shaft. The shaft coupling is configured to transmit the rotation of the output shaft to the rotating beam when switching from the first state to the second state and when switching from the second state to the first state, but not to transmit the rotation of the output shaft to the rotating beam in the first state.
[0008] In the hydroelectric power generation apparatus described above, the shaft coupling may have a first flange fixed to the end of the rotating beam and protruding from the outer surface of the rotating beam, a second flange fixed to the end of the output shaft and protruding from the outer surface of the output shaft, and a pin. The first flange may have a first through-hole formed therein that penetrates the first flange in the thickness direction. The second flange may have a second through-hole formed therein that penetrates the second flange in the thickness direction and to which the pin is fixed. The first flange and the second flange may face each other such that the first and second through-holes overlap. The pin may protrude from the second flange so as to be inserted into the first through-hole. The inner diameter of the first through-hole may be larger than the outer diameter of the pin.
[0009] In the hydroelectric power generation apparatus described above, the first flange and the second flange may be facing each other with a gap between them. In the hydroelectric power generation apparatus described above, the gap between the first flange and the second flange may be 1 mm or more.
[0010] In the hydroelectric power generation device described above, the difference between the inner diameter of the first through-hole and the outer diameter of the pin may be 2 mm or more.
[0011] The hydroelectric power generation apparatus described above may further include beams positioned to cross the waterway. The hydroelectric power generation modules may be fixed to the beams in the first state. [Effects of the Invention]
[0012] According to the hydroelectric power generation device of the present invention, fretting between gears included in the reduction gear can be suppressed. [Brief explanation of the drawing]
[0013] [Figure 1] This is a perspective view of the hydroelectric power generation device 100, seen from the front and above. [Figure 2] This is a front view of the hydroelectric power generation device 100. [Figure 3] This is an enlarged view of section III in Figure 2. [Figure 4]It is a cross-sectional view of the shaft coupling 70 in the hydraulic power generation device 100. [Figure 5] It is a perspective view of the hydraulic power generation device 100 seen from below the back. [Figure 6] It is an enlarged view at VI in FIG. 5. [Figure 7] It is a schematic diagram showing the positional relationship between the through-hole 71c and the pin 73 in the first state. [Figure 8] It is a schematic diagram showing the positional relationship between the through-hole 71c and the pin 73 while switching from the first state to the second state. [Figure 9] It is a schematic diagram showing the positional relationship between the through-hole 71c and the pin 73 while switching from the second state to the first state. [Figure 10] It is a cross-sectional view of the shaft coupling 70 in the hydraulic power generation device according to the comparative example.
Embodiments for Carrying out the Invention
[0014] Details of the embodiments of the present invention will be described while referring to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and duplicate explanations will not be repeated.
[0015] (Configuration of the Hydraulic Power Generation Device According to the Embodiment) Hereinafter, the configuration of the hydraulic power generation device (referred to as "hydraulic power generation device 100") according to the embodiment will be described.
[0016] FIG. 1 is a perspective view of the hydraulic power generation device 100 seen from above the front. FIG. 2 is a front view of the hydraulic power generation device 100. FIG. 3 is an enlarged view at III in FIG. 2. FIG. 4 is a cross-sectional view of the shaft coupling 70 in the hydraulic power generation device 100. FIG. 5 is a perspective view of the hydraulic power generation device 100 seen from below the back. FIG. 6 is an enlarged view at VI in FIG. 5.
[0017] <Installation State and Schematic Configuration of the Hydraulic Power Generation Device 100> As shown in Fig. 1, the hydroelectric power generation device 100 is installed in the water channel 200. The water channel 200 has side walls 201, side walls 202, and a bottom wall 203. The side walls 201 and the side walls 202 face each other at intervals in the first direction DR1. The bottom wall 203 is connected to the lower ends of the side wall 201 and the side wall 202. The side walls 201, the side walls 202, and the bottom wall 203 extend in the second direction DR2. The second direction DR2 is a direction that intersects (preferably perpendicular) the first direction DR1. Water flows through the space defined by the side walls 201, the side walls 202, and the bottom wall 203. That is, the water in the water channel 200 flows in the second direction DR2.
[0018] As shown in Figs. 1 to 6, the hydroelectric power generation device 100 has a beam 10, a bearing unit 20, a rotating beam 30, a pedestal 40, a hydroelectric power generation module 50, a speed reducer 60, a shaft coupling 70, and a fixing part 80.
[0019] <Beam 10> The beam 10 extends in the first direction DR1. Both ends of the beam 10 in the first direction DR1 are respectively arranged above the upper ends of the side wall 201 and the side wall 202. That is, the beam 10 is arranged so as to cross the water channel 200.
[0020] <Bearing unit 20> The bearing unit 20 is attached to the beam 10. The number of the bearing units 20 is plural. The plurality of bearing units 20 are arranged at intervals in the first direction DR1. The bearing unit 20 has a case 21 and a bearing 22. The bearing 22 is arranged inside the case 21. The bearing 22 is, for example, a rolling bearing.
[0021] <Rotating beam 30 and pedestal 40> The rotating beam 30 extends in a first direction DR1. The rotating beam 30 is supported by a bearing unit 20 (bearing 22) so as to be rotatable around its central axis. In the first direction DR1, the rotating beam 30 has a first end 30a and a second end 30b (not shown). The second end 30b is the end opposite to the first end 30a. The frame 40 is attached to the rotating beam 30. The frame 40 is attached to the rotating beam 30 by, for example, welding. In a cross-sectional view perpendicular to the first direction DR1, the rotating beam 30 is circular.
[0022] <Hydroelectric Power Module 50> The hydroelectric power generation module 50 includes a water turbine 51, a rotating shaft 52 (not shown), a gearbox 53, a support column 54, a housing 55, a generator 56 (not shown), and a rotating shaft 57 (not shown).
[0023] The water turbine 51 is positioned in the water flowing through the waterway 200. The water turbine 51 faces upstream of the waterway 200. The water turbine 51 is rotated by the water flowing through the waterway 200. The water turbine 51 is attached to a rotating shaft 52. The rotating shaft 52 rotates in conjunction with the rotation of the water turbine 51. The rotating shaft 52 is connected to a gearbox 53.
[0024] The support column 54 extends in a third direction DR3. The third direction DR3 intersects (preferably perpendicular to) the first direction DR1 and the second direction DR2. The support column 54 is connected to the gearbox 53 at one end in the third direction DR3 and to the housing 55 at the other end in the third direction DR3. The support column 54 is cylindrical with a hollow interior.
[0025] The housing 55 is supported and fixed by the frame 40. The hydroelectric power module 50 is then attached to the rotating beam 30. A generator 56 is located inside the housing 55. The rotating shaft 57 extends in a third direction DR3 within the support column 54. The rotating shaft 57 is connected to the gearbox 53 at one end in the third direction DR3 and to the generator 56 at the other end in the third direction DR3.
[0026] The gearbox 53 transmits the rotation of the rotating shaft 52 to the rotating shaft 57 after increasing its speed and changing its direction. The generator 56 generates electricity using the rotating shaft 57. In this way, the generator 56 generates electricity using the water flowing through the waterway 200.
[0027] <Reducer 60> The reduction gear 60 has an input shaft 61 and an output shaft 62. The reduction gear 60 reduces the rotation of the input shaft 61 and transmits it to the output shaft 62. This reduction is performed, for example, using gears (e.g., worm gears) located inside the reduction gear 60. The gears included in the reduction gear 60 are meshed to have a predetermined amount of backlash. Although not shown, the input shaft 61 is rotated by a motor 63. However, the input shaft 61 may be rotated manually.
[0028] The output shaft 62 extends in the first direction DR1 and rotates around its central axis as the input shaft 61 rotates. The output shaft 62 has a tip 62a in the first direction DR1. The tip 62a faces the first end 30a at a distance in the first direction DR1. In a cross-sectional view perpendicular to the first direction DR1, the output shaft 62 is circular.
[0029] <Shaft coupling 70> The shaft coupling 70 includes a first member 71, a second member 72, and a pin 73. The first member 71 has a cylindrical portion 71a and a flange 71b. The second member 72 has a cylindrical portion 72a and a flange 72b.
[0030] The cylindrical portion 71a is cylindrical and extends in the first direction DR1. The first member 71 is fixed to the rotating beam 30 by press-fitting the first end 30a of the rotating beam 30 into the cylindrical portion 71a. The flange 71b is located at the end of the cylindrical portion 71a on the first end 30a side. The flange 71b protrudes from the outer circumferential surface of the rotating beam 30 into a plane perpendicular to the first direction DR1.
[0031] A through-hole 71c is formed in the flange 71b. The through-hole 71c penetrates the flange 71b in the thickness direction (first direction DR1). The through-hole 71c is circular in a cross-sectional view perpendicular to the first direction DR1. There are multiple through-holes 71c. The multiple through-holes 71c are arranged at equal intervals in the circumferential direction. The inner diameter of the through-hole 71c is denoted as inner diameter D1.
[0032] The cylindrical portion 72a is cylindrical and extends in the first direction DR1. The second member 72 is fixed to the output shaft 62 by press-fitting the tip 62a side of the output shaft 62 into the cylindrical portion 72a. The flange 72b is located at the tip 62a side end of the cylindrical portion 72a. The flange 72b protrudes from the outer circumferential surface of the output shaft 62 into a plane perpendicular to the first direction DR1.
[0033] A through-hole 72c is formed in the flange 72b. The through-hole 72c penetrates the flange 72b in the thickness direction (first direction DR1). The through-hole 72c is circular in a cross-sectional view perpendicular to the first direction DR1. There are multiple through-holes 72c. The number of through-holes 72c is equal to the number of through-holes 71c. The multiple through-holes 72c are arranged at equal intervals in the circumferential direction. The through-holes 72c are located in positions that overlap with the through-holes 71c when viewed along the first direction DR1.
[0034] Flanges 71b and 72b face each other in a first direction DR1. Preferably, flanges 71b and 72b face each other with a gap between them in a first direction DR1. The distance between flanges 71b and 72b in a first direction DR1 is denoted as distance L. Distance L is, for example, 1 mm or more. That is, it is preferable that the clearance between flanges 71b and 72b is 1 mm or more.
[0035] There are multiple pins 73. The number of pins 73 is equal to the number of through holes 72c (through holes 71c). The pins 73 extend in a first direction DR1. In a cross-sectional view perpendicular to the first direction DR1, the pins 73 are, for example, circular. The pins 73 are fixed to the flange 72b by being press-fitted into the through holes 72c. The pins 73 protrude from the flange 72b toward the flange 71b. The pins 73 are inserted into the through holes 71c. The outer surface of the pins 73 is not in contact with the inner wall surface of the through holes 71c. Preferably, the pins 73 are located in the center of the through holes 71c.
[0036] Let the outer diameter of pin 73 be D2. Outer diameter D2 is smaller than inner diameter D1. From another perspective, pin 73 is movable relative to flange 71b in a plane perpendicular to the first direction DR1 within the through hole 71c. The difference between inner diameter D1 and outer diameter D2 is preferably 2 mm or more. That is, the clearance of pin 73 with respect to the through hole 71c is preferably 1 mm or more.
[0037] <Fixed part 80> The fixing part 80 includes, for example, a first member 81, a second member 82, a rod-shaped body 83, and a toggle clamp 84.
[0038] The first member 81 is attached to the frame 40. The first member 81 has a hole 81a (not shown). The second member 82 is attached to the beam 10. The second member 82 has a hole 82a. Holes 81a and 82a are arranged on a single imaginary straight line. The rod-shaped body 83 is inserted into both holes 81a and 82a. This prevents the rotation of the rotating beam 30 (rotation of the hydroelectric power generation module 50) and maintains the state in which the turbine 51 is submerged in the water flowing through the waterway 200. Hereinafter, the state in which the turbine 51 is submerged in the water flowing through the waterway 200 may be referred to as the first state, and the state in which the turbine 51 is lifted out of the water flowing through the waterway 200 may be referred to as the second state.
[0039] The toggle clamp 84 presses the first member 81 toward the beam 10. This further firmly prevents the rotation of the rotating beam 30 (rotation of the hydroelectric power module 50). By pulling the rod-shaped body 83 out of holes 81a and 82a and releasing the pressure from the toggle clamp 84, the rotating beam 30 (hydroelectric power module 50) becomes rotatable. The configuration of the fixing part 80 is not limited to the above. The fixing part 80 is not particularly limited as long as it can switch between a state in which the rotation of the rotating beam 30 (hydroelectric power module 50) is prevented and a state in which the rotating beam 30 (hydroelectric power module 50) is rotatable.
[0040] <Rotational movement of the rotating beam 30> A hydroelectric power generation module 50 is attached to the rotating beam 30. As a result, the hydroelectric power generation module 50 rotates as the rotating beam 30 rotates, and the water turbine 51 is lifted out of the state where it is flowing in the water channel 200. In other words, by rotating the rotating beam 30, the system switches from the first state to the second state.
[0041] Figure 7 is a schematic diagram showing the positional relationship between the through-hole 71c and the pin 73 in the first state. As shown in Figure 7, in the first state, the inner wall surface of the through-hole 71c and the outer circumferential surface of the pin 73 are not in contact. Figure 8 is a schematic diagram showing the positional relationship between the through-hole 71c and the pin 73 during the transition from the first state to the second state. As shown in Figure 8, by rotating the output shaft 62, the outer circumferential surface of the pin 73 comes into contact with the inner wall surface of the through-hole 71c. As a result, the rotation of the output shaft 62 is transmitted to the rotating beam 30 via the shaft coupling 70. When the rotation of the output shaft 62 is transmitted to the rotating beam 30, the rotating beam 30 rotates, and the transition from the first state to the second state occurs.
[0042] Figure 9 is a schematic diagram showing the positional relationship between the through-hole 71c and the pin 73 during the transition from the second state to the first state. As shown in Figure 9, even during the transition from the second state to the first state, the output shaft 62 rotates in the reverse direction, causing the outer surface of the pin 73 to contact the inner wall surface of the through-hole 71c. Therefore, the reverse rotation of the output shaft 62 is transmitted to the rotating beam 30 via the shaft coupling 70, causing the rotating beam 30 to rotate in the reverse direction and the transition from the second state to the first state to occur.
[0043] After switching from the second state to the first state, the rotation of the output shaft 62 is adjusted so that the outer surface of the pin 73 does not come into contact with the inner wall surface of the through hole 71c (preferably so that the pin 73 is centered in the through hole 71c).
[0044] (Effects of the hydroelectric power generation device according to the embodiment) The effects of hydroelectric power generation device 100 will be explained below in comparison with a comparative example.
[0045] The configuration of the comparative example hydroelectric power generation apparatus is the same as that of the hydroelectric power generation apparatus 100, except for the details of the shaft coupling 70. Figure 10 is a cross-sectional view of the shaft coupling 70 in the comparative example hydroelectric power generation apparatus. As shown in Figure 10, in the comparative example hydroelectric power generation apparatus, the pin 73 is fixed in the through hole 71c by press-fitting. That is, in the comparative example hydroelectric power generation apparatus, the rotating beam 30 and the output shaft 62 always rotate together.
[0046] The rotating beam 30 may experience vibrations due to fluctuations in the force applied to the water turbine 51 from the water flowing through the waterway 200. In the hydroelectric power generation apparatus according to the comparative example, the rotating beam 30 and the output shaft 62 always rotate together, so these vibrations are transmitted to the output shaft 62. If these vibrations cause the output shaft 62 to rotate in a manner that exceeds the backlash amount of the gears in the reduction gear 60, the gears in the reduction gear 60 will come into contact with each other, causing fretting. Fretting shortens the lifespan of the gears in the reduction gear 60.
[0047] In the hydroelectric power generation device 100, in the first state, the outer surface of the pin 73 and the inner wall surface of the through hole 71c are not in contact, so the rotating beam 30 and the output shaft 62 do not rotate together. Therefore, even if vibration is applied to the rotating beam 30, unless this vibration is excessively large, it will not be transmitted to the output shaft 62 and will not cause the output shaft 62 to rotate. Since the output shaft 62 does not rotate, fretting of the gears included in the reduction gear 60 is also suppressed in the hydroelectric power generation device 100. Furthermore, if the flanges 71b and 72b are spaced apart and facing each other in the first direction DR1, the co-rotation of the rotating beam 30 and the output shaft 62 becomes even less likely.
[0048] Although embodiments of the present invention have been described above, it is possible to modify these embodiments in various ways. Furthermore, the scope of the present invention is not limited to the embodiments described above. The scope of the present invention is indicated by the claims and is intended to include all modifications within the meaning and scope equivalent to the claims. [Industrial applicability]
[0049] The above embodiments are particularly advantageous to hydroelectric power generation equipment. [Explanation of Symbols]
[0050] 100 Hydroelectric power generation device, 10 Beam, 20 Bearing unit, 21 Case, 22 Bearing, 30 Rotating beam, 30a First end, 30b Second end, 40 Frame, 50 Hydroelectric power generation module, 51 Turbine, 52 Rotating shaft, 53 Gearbox, 54 Support column, 55 Housing, 56 Generator, 57 Rotating shaft, 60 Reducer, 61 Input shaft, 62 Output shaft, 62a End, 63 Motor, 70 Shaft coupling, 71 First member, 71a Cylindrical part, 71b Flange, 71c Through hole, 72 Second member, 72a Cylindrical part, 72b Flange, 72c Through hole, 73 Pin, 80 Fixing part, 81 First member, 81a Hole, 82 Second member, 82a Hole, 83 Rod-shaped body, 84 Toggle clamp, 200 Channel, 201,202 side wall, 203 bottom wall, D1 inner diameter, D2 outer diameter, DR1 1st direction, DR2 2nd direction, DR3 3rd direction, L distance.
Claims
1. A hydroelectric power generation device located in a waterway, Rotating beam and A hydroelectric power generation module with a water turbine, A gearbox having an input shaft and an output shaft, Equipped with a shaft coupling, The rotating beam is supported so as to be rotatable around its central axis, The hydroelectric power generation module is attached to the rotating beam, As the rotating beam rotates, the turbine is switched between a first state in which it is submerged in the water flowing through the channel and a second state in which it is lifted out of the water flowing through the channel. The reduction gear reduces the rotation of the input shaft and transmits it to the output shaft. The shaft coupling is configured to transmit the rotation of the output shaft to the rotating beam when switching from the first state to the second state and when switching from the second state to the first state. The system further comprises beams arranged to cross the aforementioned waterway, In the first state, the hydroelectric power generation module is fixed to the beam. The shaft coupling has a first flange fixed to the end of the rotating beam and extending from the outer surface of the rotating beam, a second flange fixed to the end of the output shaft and extending from the outer surface of the output shaft, and a pin. The first flange has a first through hole formed therein that penetrates the first flange in the thickness direction. The second flange has a second through-hole formed therein, which penetrates the second flange in the thickness direction and is into which the pin is fixed. The first flange and the second flange are positioned opposite each other such that the first through hole and the second through hole overlap. The pin protrudes from the second flange so as to be inserted into the first through hole. The inner diameter of the first through hole is larger than the outer diameter of the pin. The first flange and the second flange are facing each other with a gap between them. A hydroelectric power generation device in which the difference between the inner diameter of the first through hole and the outer diameter of the pin is 2 mm or more.
2. The hydroelectric power generation apparatus according to claim 1, wherein the distance between the first flange and the second flange is 1 mm or more.