JP2008208959A - Speed increasing gear and wind power generating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a speed increasing gear for producing a great speed increasing ratio with one stage, and to provide a compact wind power generating device using the same. <P>SOLUTION: The speed increasing gear 2 is provided for increasing the speed of rotation of a wind turbine main shaft 1a of the wind power generating device and transmitting it to a rotor 3a of an induction generator 3. Herein, the rotation of the spindle 1a as an input shaft is transmitted to external gears 6a, 6b rotatably supported on eccentric shaft portions 7a, 7b of an output shaft 2a, the external gears 6a, 6b are engaged at their external teeth with outer pins 9 on the inner periphery of a casing 8 and revolved by one rotation in the opposite direction to the rotating direction during the rotation by a difference between the number of the external teeth and the number of the outer pins 9, and the revolving motion is transmitted to the output shaft 2a to produce a great speed increasing ratio with one stage. Thus, the wind power generating device does not require the speed increasing gear in conventional multiple stages, where a nacelle 4 is shorter in proportion as an installation space for the speed increasing gear is shorter in the axial direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a speed increaser that speeds up rotation input to an input shaft and outputs it from an output shaft, and a wind turbine generator using the speed increaser.

A wind turbine generator generates power by driving a generator by the rotation of a windmill. When an induction generator is used as the generator, the rotation of the windmill is between the main spindle of the windmill and the rotor of the generator. It is necessary to provide a speed increaser that increases the speed at a speed higher than the synchronous speed of the generator. An example of a gearbox incorporated in such a wind turbine generator is shown in FIG. 2 (see Patent Document 1). In this example, two planetary roller type friction transmission speed increasers 51 and 52 are directly connected in the axial direction, the rotation of the input shaft 53 of the first stage speed increaser 51 is transmitted to the ring roller 54, and the ring roller 54 To the sun axis 56 via the planetary roller 55. Then, the rotation of the first-stage sun shaft 56 is connected to the flange portion of the sun shaft 56 and is guided to the second-stage ring roller 57 through the second-stage planetary roller 58. An output shaft 59 that is a shaft is rotated.
JP-A-7-54763

  Here, in the example shown in FIG. 2, the two speed increasers are incorporated by being directly connected in the axial direction for the following reason. That is, in such a planetary roller type gearbox, the speed increase ratio is determined by the ratio of the inner diameter of the ring roller and the outer diameter of the sun shaft, so the speed increase ratio is set to several times due to design restrictions. It is common to do. On the other hand, in a wind turbine generator using an induction generator, it is necessary to increase the rotational speed of a wind turbine of about several tens of rpm to a speed higher than the generator synchronous speed (usually 1500 to 1800 rpm). Therefore, the required large speed increase ratio is obtained by directly connecting and installing the two speed increasers.

  However, in the wind turbine generator in which the gearboxes are incorporated in multiple stages as described above, the nacelle that houses these gearboxes and the generators becomes longer in the axial direction, which increases the size of the entire device. This contributes to raising costs and lowering workability during installation.

  In addition, in a wind power generator using an induction generator, a planetary gear type or a helical gear type may be adopted as a speed increaser. In this case, the planetary roller type speed increaser is also used. Similarly to the case, since it is difficult to obtain a required speed increase ratio with a one-stage speed increaser, the speed increaser is incorporated in multiple stages, and the nacelle becomes longer.

  An object of the present invention is to provide a speed increaser capable of obtaining a large speed increase ratio in a single stage and a compact wind power generator using the speed increaser.

  In order to solve the above-described problems, a speed increaser of the present invention includes an input shaft, an eccentric shaft portion at one end portion, an output shaft disposed coaxially with the input shaft, and rotating to the eccentric shaft portion. It is freely supported and meshes with the internal teeth provided on the inner periphery of the casing, and is provided between the external gear having a smaller number of teeth than the internal teeth, and between the input shaft and the external gear, thereby rotating the input shaft. Because it is composed of torque transmission means that transmits to the external gear, the external gear revolves while rotating by the torque transmitted from the input shaft, and the revolving motion is transmitted to the output shaft. is there.

  That is, in this speed increaser, when the input shaft rotates, the rotation is transmitted to the external gear supported by the eccentric shaft portion of the output shaft via the torque transmission means, and the external gear rotates around the eccentric shaft portion. At this time, since the external gear meshes with the internal teeth provided on the inner periphery of the casing, and the number of external teeth is smaller than the number of internal teeth, the external gear rotates by the difference in the number of teeth between the external teeth and the internal teeth. In the meantime, it revolves by one rotation around the output shaft in the direction opposite to the rotation direction, and the revolving motion is transmitted to the output shaft. Accordingly, the rotation of the input shaft is accelerated and transmitted to the output shaft, and a large speed increase ratio can be obtained even with only one stage by simply setting the number of external teeth and internal teeth.

  In the above-described configuration, the external gear of the external gear has a trochoidal curve tooth profile and the internal tooth is an external pin, so that the meshing rate can be increased, and the speed increase with excellent durability with less tooth breakage. You can get a chance.

  Further, there are two eccentric shaft portions formed on the output shaft, the phases of the two eccentric shaft portions are shifted by 180 °, the external gear is provided on the outer periphery of each eccentric shaft portion, and each external gear and the input shaft are By providing the torque transmission means between each other, the power of the input shaft can be transmitted from the two paths to the output shaft, so the load of the rotational power transmitted from one path is reduced and more stable rotation is achieved. Power can be transmitted, and vibrations generated by the eccentric rotation of the eccentric shaft portion can be canceled each other, and a speed up gear with less vibration can be obtained.

  Further, as the torque transmission means, a plurality of inner pins are provided on one of the opposed surfaces of the input shaft and the external gear at equal intervals on a concentric circle, and the inner pins are formed on the other of the opposed surfaces. It is possible to adopt a structure in which the hole is inserted into a circular hole having a larger diameter and is in contact with a part of the inner wall of the circular hole.

  Here, if a roller is rotatably fitted to each inner pin and the roller is brought into contact with a part of the inner wall of the circular hole, the contact between the inner pin and the circular hole becomes a rolling contact, so that the contact resistance is reduced. Torque loss can be reduced.

  The wind turbine generator according to the present invention includes a wind turbine that rotates about the main shaft by wind power, a speed increasing device configured as described above that uses the main shaft of the wind turbine as an input shaft, and accelerates and outputs the rotation. And an induction generator having a rotor connected to the output shaft of the machine.

  That is, it is necessary to make the speed increaser have a multistage configuration as in the prior art by incorporating a speed increaser capable of obtaining a large speed increase ratio in one stage as described above between the wind turbine and the rotor of the induction generator. As a result, the length of the nacelle can be shortened by the amount that the space for installing the gearbox is shorter in the axial direction than before.

  As described above, when the input shaft rotates, the speed increaser of the present invention rotates the output shaft while the external gear supported by the eccentric shaft portion of the output shaft rotates by the difference in the number of teeth between the external teeth and the internal teeth. As a result, the revolution movement is transmitted to the output shaft in the direction opposite to the rotation direction, and the rotation of the input shaft can be transmitted to the output shaft with a large speed increase ratio.

  In addition, the wind power generator of the present invention incorporates the above speed increaser between the wind turbine and the rotor of the induction generator so that the required speed increase ratio can be obtained with a single speed increaser. Compared with the prior art, the length of the nacelle can be shortened and the entire apparatus can be made compact.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG. This wind power generator has a plurality of blades 1b at one end of a main shaft 1a, and a wind turbine 1 that rotates around the main shaft 1a by wind power, and a speed increaser that increases the speed of rotation of the main shaft 1a of the wind turbine 1 and outputs it. 2 and an induction generator 3 having a rotor 3a connected to the output shaft 2a of the speed increaser 2, and a tower 5 standing on the ground with a nacelle 4 housing the speed increaser 2 and the generator 3 It is attached to the upper end of.

  The speed increaser 2 has its output shaft 2a coaxially arranged with the wind turbine main shaft 1a as an input shaft, and two external gears 6a and 6b whose outer teeth are trochoidal curved teeth are respectively connected to one end of the output shaft 2a. The two eccentric shaft portions 7a and 7b provided in the portion are rotatably supported and meshed with a plurality of external pins (internal teeth) 9 provided on the inner periphery of the casing 8, and the external gear 6a of the main shaft 1a A plurality of inner pins 10 concentrically mounted on the opposite surface of the outer gear 6 are formed into circular holes having a diameter larger than the inner pin diameter concentrically formed on the opposite surfaces of the external gears 6a and 6b to the main shaft 1a. By inserting and contacting a part of the inner wall of the circular hole, torque transmission means for transmitting the rotation of the main shaft 1a to the external gears 6a and 6b is formed between the main shaft 1a and the external gears 6a and 6b. .

  The two eccentric shaft portions 7a and 7b of the output shaft 2a are provided with a 180 ° phase shift in the circumferential direction so as to cancel vibrations generated by the eccentric rotation. Further, each outer pin 9 and each inner pin 10 are in rolling contact with the external teeth and circular holes of the external gears 6a and 6b via rollers rotatably fitted on the outer circumferences. Torque loss is suppressed.

  When the main shaft 1a rotates, the inner pin 10 pushes the inner walls of the circular holes of the outer gears 6a and 6b, and rotates the outer gears 6a and 6b around the eccentric shaft portions 7a and 7b of the output shaft 2a (spinning motion). ) At this time, each external gear 6a, 6b is guided by the outer pin 9 meshing with its external teeth while rotating, and is eccentrically rotated around the axis of the output shaft 2a (revolving motion) in the direction opposite to the rotation direction. This revolution motion is transmitted to the output shaft 2a as a rotational motion.

Here, the external gears 6a and 6b have fewer external teeth than the number of external pins 9, and the external gears 6a and 6b rotate the output shaft 2a while rotating by the difference between the external teeth and the external pins 9. Revolves one revolution in the opposite direction to the center of rotation. Accordingly, the rotation of the main shaft 1a is accelerated and transmitted to the output shaft 2a. The speed increasing ratio is such that the number of external pins 9 is Z ₁ and the number of external teeth of the external gears 6a and 6b is Z _2. Then, it is calculated by Z ₂ / (Z ₁ −Z ₂ ). That is, in this speed increaser 2, there are few design restrictions in setting the speed increase ratio, and a large speed increase ratio required for the wind turbine generator even at one stage can be obtained by setting Z ₁ and Z ₂ appropriately. Is obtained.

  In the induction generator 3, the rotor 3a is connected to the output shaft 2a of the speed increaser 2, and the stator 3b attached to the inner surface of the box-shaped mounting member 11 is disposed outside the rotor 3a. When the rotation of the windmill 1 is increased by the speed increaser 2 to a speed equal to or higher than the synchronous speed and transmitted to the rotor 3a, electric power is generated.

  This wind power generator is configured as described above, and the speed increaser 2 capable of obtaining a large speed increase ratio in one stage is incorporated between the wind turbine 1 and the rotor 3a of the induction generator 3 to increase the speed as in the conventional case. Since the speed gear need not have a multi-stage configuration, the nacelle 4 is shortened by the amount that the speed increasing gear installation space is shortened in the axial direction as compared with the prior art, and the entire apparatus is compact.

Longitudinal front view of a wind turbine generator incorporating the gearbox of the embodiment Longitudinal front view of an example of a gearbox incorporated in a conventional wind turbine generator

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Windmill 1a Main shaft 1b Blade 2 Speed increaser 2a Output shaft 3 Induction generator 3a Rotor 3b Stator 4 Nacelle 5 Tower 6a, 6b External gear 7a, 7b Eccentric shaft part 8 Casing 9 Outer pin 10 Inner pin

Claims (6)

  An input shaft, having an eccentric shaft portion at one end, meshed with an output shaft disposed coaxially with the input shaft, and internal teeth provided on the inner periphery of the casing and rotatably supported by the eccentric shaft portion And an external gear having a smaller number of teeth than the internal teeth, and a torque transmission means provided between the input shaft and the external gear for transmitting the rotation of the input shaft to the external gear. A speed increaser that revolves while rotating by the torque transmitted from the input shaft, and that the revolving motion is transmitted to the output shaft.   The speed increaser according to claim 1, wherein the external teeth of the external gear are trochoidal curved teeth and the internal teeth are external pins.   There are two eccentric shaft portions formed on the output shaft, the phases of the two eccentric shaft portions are shifted by 180 °, the external gear is provided on the outer periphery of each eccentric shaft portion, and each external gear and the input shaft are The speed increaser according to claim 1, wherein the torque transmission means is provided on the speed increasing device.   The torque transmitting means is provided with a plurality of inner pins at equal intervals on one of the opposed surfaces of the input shaft and the external gear at equal intervals, and the inner pins are larger in diameter than the inner pin diameter formed on the other of the opposed surfaces. The speed increasing device according to any one of claims 1 to 3, wherein the step-up gear is configured to be inserted into the circular hole and to be in contact with a part of the inner wall of the circular hole.   The speed increaser according to claim 4, wherein a roller is rotatably fitted to each inner pin, and the roller is brought into contact with a part of the inner wall of the circular hole.   A wind turbine that rotates around a main shaft by wind power, a main shaft of the wind turbine as an input shaft, and the rotation speed is increased and output. A wind turbine generator including an induction generator having a rotor connected to an output shaft.

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