JP2005036880A - Planetary gear device and its rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a planetary gear device to be used in a wind power generator speed increasing gear for smoothing the rotating operation of planetary gears at restarting operation under irregular operating conditions and actualizing maintenance-free operation over a long period. <P>SOLUTION: The planetary gear device 3 comprises the planetary gears 8 rotatably supported via a rolling bearing 9 at a plurality of peripheral places on a turnable carrier 7. The rolling bearing 9 for supporting the planetary gears 8 gets in and out of an oil bath 16 in a casing 6 with the turn of the carrier 7. The used rolling bearing 9 has rolling bodies formed of hollow rollers 27. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a machine or device, for example, a wind power generator, in which the lubrication system of the bearing supporting the planetary gear is an oil bath system, the bearing enters and exits the oil bath by the rotation of the carrier, and the carrier rotation is irregular. TECHNICAL FIELD The present invention relates to a planetary gear device used for a speed increaser and the like and a rolling bearing thereof.

  The speed increaser for wind power generators incorporates a planetary gear device as speed increasing means (for example, Non-Patent Document 1). Oil bath lubrication is often used to lubricate the rolling bearings of the planetary gears. In this case, there are three or four planetary shafts. When the planetary shaft is revolved and positioned at the bottom, the planetary shaft bearing is immersed in an oil bath, and lubricating oil is supplied.

In addition to oil bath lubrication, there are various types of lubrication for general rolling bearings, such as grease lubrication. For example, the roller is hollow or a lubricating oil reservoir is provided to fill the inside with a lubricant. What was made is also proposed (for example, patent document 1).
Mechanical Design Vol. 46, No. 13 (September 2002), pages 90-96 JP 2000-35046 A

  In the planetary gear unit of a wind turbine speed increaser, the planetary shaft is immersed in an oil bath and supplied with lubricating oil only when it is revolved and positioned at the bottom. For this reason, of course, some bearings are not soaked in lubricating oil at some point. In the case of wind power generation, depending on the wind conditions, the wind power generation may stop for a long time without rotating. Then, in the planetary shaft bearing, the lubricating oil of the bearing not immersed in the oil bath flows down, and there is almost no lubricating oil. Such a planetary shaft that has been stopped for a long time and has almost no lubricating oil rotates suddenly due to a change in wind conditions. As a result, poor lubrication occurs, and it may not be possible to perform an annular rotation. This leads to a decrease in wind power generation efficiency and hinders the extension of the bearing life.

  It should be noted that if a grease lubrication or a type of bearing in which a lubricating oil reservoir is provided and the lubricating oil is retained is used, smooth rotation is possible even after sudden resumption of rotation after a long stop. A wind turbine speed increaser is required to operate without maintenance for a long period of about 20 years, and such a long lubrication life cannot be obtained in a grease lubrication or lubricating oil filling type.

  In addition to the speed increaser for wind power generators, the planetary gear device used for irregular rotation as described above has a problem of bearing lubrication similar to that for wind power generation.

  The object of the present invention is to enable smooth rotation of the planetary gear at the time of restarting operation and maintenance for many years even when used under irregular operating conditions where the stop time is long and sudden rotation restarts. It is to provide a planetary gear device that can be operated free of charge.

  Another object of the present invention is to provide a wind turbine speed increaser that can perform a smooth rotating operation when resuming operation and that can be operated maintenance-free for many years.

  Still another object of the present invention is to provide a rolling bearing capable of effectively realizing such a planetary gear device.

  In the planetary gear device of the present invention, planetary gears are rotatably supported via a rolling bearing at a plurality of locations in the circumferential direction of a rotatable carrier, and the rolling bearings supporting the planetary gears are casings by the rotation of the carrier. In the planetary gear device that enters and exits the internal oil bath, a rolling bearing having rolling elements made of hollow rollers is used as the rolling bearing.

  According to this configuration, the rolling bearing that supports the planetary gear is revolved by the rotation of the carrier and immersed in the oil bath when it is positioned at the bottom, and lubricating oil is supplied. At this time, the lubricating oil in the oil bath is held in the hollow portion of the hollow roller of the rolling bearing. Therefore, even if the lubricating oil gradually flows out due to a long-time stop, the lubricating oil in the rolling bearing is not insufficient, and can rotate smoothly even when sudden operation restarts. Moreover, since it is an oil bath circulation, it can be operated maintenance-free for many years.

  The planetary gear device of the present invention includes, for example, an internal ring gear that is provided on the casing and meshes with the plurality of planetary gears, and a sun gear that is rotatably provided at a position concentrically with the ring gear and meshes with the plurality of planetary gears. And a planetary gear device for speed-up in which the carrier serves as an input unit and the sun gear serves as an output unit.

  In the planetary gear device for speed increase, the driving force on the input side is stronger than that for speed reduction. Therefore, the bearing supporting the planetary gear is forcibly rotated. Therefore, even if the lubrication state is somewhat poor, the bearing is forced to rotate, and damage is accumulated in the bearing. However, since a long life is required, higher reliability is required for the bearing. Therefore, the effect of maintaining lubricity due to the use of the hollow roller is more effectively exhibited.

  The step-up gear for wind power generator according to the present invention includes the planetary gear device having the above-described configuration according to the present invention.

  The speed increaser for wind power generators often stops for a long time depending on wind conditions, and then suddenly resumes rotation, and is required to be maintenance-free for many years. The effect of being able to perform smooth rotating operation constantly under irregular driving conditions and maintenance-free operation for many years is exhibited very effectively.

  A rolling bearing according to the present invention is a rolling bearing that rotatably supports a planetary gear of a planetary gear device on a carrier, and moves into and out of an oil bath by the rotation of the carrier, wherein the rolling element is formed of a hollow roller. .

  In this way, in the bearing used for oil bath lubrication, the hollow roller is used as the rolling element, so that it can be used under irregular operating conditions and can always rotate smoothly and can be maintenance-free for a long time. .

  The planetary gear device of the present invention uses a hollow roller as a rolling element for a rolling bearing of an oil bath lubricated planetary gear, so that it is used under irregular operating conditions where the stop time is long and sudden rotation restarts. However, when the operation is resumed, the planetary gear can be smoothly rotated, and the maintenance-free operation can be performed for many years.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a step-up gear for wind power generator equipped with a planetary gear device. This speed increaser includes a planetary gear device 3 that accelerates the rotation of the input shaft 1 and transmits it to the low speed shaft 2, and a secondary speed increase device that further accelerates the rotation of the low speed shaft 2 and transmits it to the output shaft 4. 5. The planetary gear device 3 and the secondary speed increasing device 5 are provided in a common casing 6. The input shaft 1 is connected to a main shaft (not shown) of a windmill (not shown) and the output shaft 4 is connected to a generator (not shown).

  In the planetary gear device 3, planetary shafts 10 are provided at a plurality of locations in the circumferential direction of the rotatable carrier 7, and planetary gears 8 are rotatably supported on the planetary shafts 10 via rolling bearings 9. In the illustrated example, two rolling bearings 9 for each planetary gear 8 are used side by side, but may be one. The carrier 7 is a member serving as an input unit in the planetary gear device 3, and is provided as an integral member with the input shaft 1 or integrally coupled. The carrier 7 is rotatably supported by the casing 6 at the portion of the input shaft 1 via bearings 11 and 11A. Each planetary gear 8 supported by the carrier 7 meshes with an internal ring gear 12 provided in the casing 6, and meshes with a sun gear 13 rotatably provided at a concentric position with the ring gear 12. The ring gear 12 may be formed directly on the casing 6 or may be fixed to the casing 6. The sun gear 13 is a component serving as an output unit in the planetary gear device 3 and is provided on the low speed shaft 2. The low speed shaft 2 is rotatably supported by the casing 6 via bearings 14 and 15.

  The secondary speed increasing device 5 is constituted by a gear train. In the illustrated example, in the secondary speed increasing device 5, the gear 17 fixed to the low speed shaft 2 meshes with the small diameter side gear 18 of the intermediate shaft 21, and the large diameter side gear 19 provided on the intermediate shaft 21 is the output shaft 4. The gear train meshes with the gear 20. The intermediate shaft 21 and the output shaft 4 are rotatably supported on the casing 6 by bearings 22 and 23, respectively.

  The lower portion of the casing 6 is a portion that forms an oil bath 16 of the lubricating oil, and the oil level L of the oil bath 16 is set to a height at which the rolling bearing 9 that supports the planetary gear 8 enters and exits by the rotation of the carrier 7. ing.

  In the rolling bearing 9 that supports each planetary gear 8, as shown in an enlarged view in the upper part of FIG. The hollow roller 27 is a roller having a hollow portion 27a opened at the roller end face. Although the hollow part 27a penetrated the both end surfaces of the hollow roller 27 is used, it does not necessarily have to penetrate.

  FIG. 3 shows a specific example of the rolling bearing 9. The rolling bearing 9 may be any type using hollow rollers 27, and various types can be adopted. In this embodiment, a cylinder in which a plurality of hollow rollers 27 are interposed between the inner ring 25 and the outer ring 26. It is a roller bearing. The rolling bearing 9 is a full-roller type bearing that does not use a cage. The outer ring 26 has both hooks and the inner ring 25 has no hooks. On the contrary, the outer ring 26 may have no wrinkles and the inner ring 25 may have both wrinkles.

  The operation of the above configuration will be described. When the input shaft 1 rotates, the carrier 7 integrated with the input shaft 1 turns, and the planetary gears 8 supported at a plurality of locations of the carrier 7 revolve. At this time, each planetary gear 8 revolves while revolving while meshing with the fixed ring gear 12 to cause rotation. The sun gear 13 is meshed with the planetary gear 8 that rotates while revolving, so that the sun gear 13 is rotated at an increased speed with respect to the input shaft 1. The sun gear 13 serving as an output part of the planetary gear device 3 is provided on the low speed shaft 2 of the secondary speed increasing device 5, and the rotation of the sun gear 13 is increased by the secondary speed increasing device 5 and output. It is transmitted to the axis 4. Thus, the rotation of the wind turbine main shaft (not shown) input to the input shaft 1 is greatly amplified by the planetary gear device 3 and the secondary speed increasing device 5 and transmitted to the output shaft 4, and the output shaft 4 Provides high-speed rotation that can generate electricity.

  Lubrication of the rolling bearing 9 that supports each planetary gear 8 is performed as follows. When the planetary gear 8 and its rolling bearing 9 are revolved by the turning of the carrier 7 and positioned at the bottom, the planetary gear 8 and its rolling bearing 9 are immersed in the oil bath 16 and supplied with lubricating oil. At this time, the lubricating oil in the oil bath 16 is held in the hollow portion 27 a of the hollow roller 27 of the rolling bearing 9. Therefore, even if the long-time stop continues due to the windless state and the lubricating oil in the rolling bearing 9 outside the oil bath 16 gradually flows out, the lubricating oil in the rolling bearing 9 does not run out. Therefore, the rolling bearing 9 can be smoothly rotated even when the operation is suddenly resumed due to a sudden blow of wind. For this reason, the fear of causing problems such as smearing and scuffing due to insufficient lubrication is eliminated. Moreover, since it is an oil bath circulation, it can be operated maintenance-free for many years.

  In the above embodiment, the rolling bearings 9 that support the planetary gears 8 are single-row bearings. However, as shown in FIG. Further, in the hollow portion 27a of the hollow roller 27, as shown in each example described later, a lubricating oil intake means and a holding means may be provided. As the taking-in means, for example, the shape of the hollow portion 27a is made to have a shape in which the action of taking the lubricating oil into the inside by the rotation of the hollow roller 27 occurs. In addition, the holding means, for example, has a shape of the hollow portion 27a in which a lubricating oil holding action is generated.

  FIG. 4B is an example of the shape that causes the capturing action and the holding action, and the hollow portion 27a is tapered. Moreover, the rolling bearing 9 of the figure is a double-row cylindrical roller bearing, and the taper shape of the hollow portion 27a of the hollow roller 27 is a taper angle at which the inner side becomes wider. As described above, by arranging the taper angle to be wide on the inside, the lubricating oil in the hollow portion 27a flows toward the inside of the bearing during the stop, so that it is difficult to leak outside the bearing. Therefore, good lubrication is maintained for longer stops. Further, during rotation, the lubricating oil is actively taken into the bearing by centrifugal force due to the tapered shape of the hollow portion 27a.

  FIG. 4C shows another example of the shape that causes the lubricating oil uptake action and the holding action. In this embodiment, the hollow portion 27a has a cylindrical surface shape, and a spiral groove 29 is formed on the inner diameter surface thereof. Usually, since the rotation direction of the hollow roller 27 is fixed, the spiral groove 29 is provided so that the spiral advances inward by the normal rotation. Thereby, during the stop, the area of the inner surface of the hollow portion 27a of the hollow roller 27 is increased by the spiral groove 29 and the contact area with the lubricating oil is increased, so that the lubricating oil is easily held by the surface tension. Further, during the rotation, the lubricating oil is positively taken into the hollow portion 27 a by the screwing effect of the spiral groove 29. The spiral groove 29 may be as fine as a turning line.

  5 (A) and 5 (B) show other examples in which the shape of the hollow portion 27a of the hollow roller 27 is changed to a shape in which the retention action of the lubricating oil is generated by increasing the surface area. In the example of FIG. 5 (A), the inner surface of the hollow portion 27a has a surface roughness that is rougher than other portions. For example, the inner surface of the hollow portion 27a is a roughened surface by shot blasting or the like. FIG. 5B is an example in which a circumferential groove 30 is provided on the inner surface of the hollow portion 27a.

  FIGS. 6A and 6B show still other examples in which a lubricating oil retaining means is provided in the hollow portion 27 a of the hollow roller 27. In the example of FIG. 6A, the sintered metal 31 is press-fitted into the inner surface of the hollow portion 27a of the hollow roller 27 as a lubricating oil retaining means. The sintered metal 31 is cylindrical. Thus, by providing the sintered metal 31 having a large porosity in the hollow roller 27, the sintered metal 31 sucks and holds the lubricating oil.

  The example of FIG. 6B shows an example in which a lubricating oil retaining film 32 is provided on the inner surface of the hollow portion 27 a of the hollow roller 27. The lubricating oil retaining film 32 is, for example, a phosphate film. The phosphate coating is highly oleophilic and improves the lubricating oil retention function. In addition, the phosphate coating also has a rust prevention effect by sucking oil.

  In each of the above embodiments, the full-roller type rolling bearing 9 is used. However, the rolling bearing 9 that supports the planetary gear 8 may be one that uses the hollow roller 27 and has a cage. There may be. As an example of the rolling bearing 9 with a cage, as shown in FIG. 7, a pin type cage having a pin 34 that is inserted into the hollow portion 27a of the hollow roller 27 and supports the hollow roller 27 freely during rotation. Those using 33 can be used. The rolling bearing 9 using this pin type retainer 33 may be a double row or a single row.

  Further, the rolling bearing 9 that supports the planetary gear 8 may be a self-aligning roller bearing as shown in FIG. 8, for example. This figure shows an example of a self-aligning roller bearing having an allowable alignment angle α.

  In addition, although the planetary gear apparatus 3 of the said embodiment was used for speed-up, it may be used for reduction. In that case, the sun gear 13 becomes an input part, and the carrier 7 becomes an output part.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the fracture | rupture side view which shows the gearbox for wind power generators provided with the planetary gear apparatus concerning 1st Embodiment of this invention, and the one part enlarged view. It is a fracture front view of the planetary gear device in the speed increasing device. (A), (B) is the partially broken side view and partially broken front view of the rolling bearing used for the planetary gear apparatus, respectively. (A)-(C) is a partially broken side view of each example of the rolling bearing used for the planetary gear apparatus, respectively. It is sectional drawing of each modification of the hollow roller of the rolling bearing. It is sectional drawing of each other modification of the hollow roller of the rolling bearing. It is sectional drawing of the other modification of a rolling bearing, and the partial front view which shows the holder | retainer. It is sectional drawing of the further another modification of a rolling bearing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Input shaft 2 ... Low speed shaft 3 ... Planetary gear apparatus 4 ... Output shaft 5 ... Secondary speed increasing device 6 ... Casing 7 ... Carrier 8 ... Planetary gear 9 ... Rolling bearing 16 ... Oil bath 27 ... Hollow roller 27a ... Hollow part

Claims (4)

Planetary gears are rotatably supported via a rolling bearing at a plurality of locations in the circumferential direction of the rotatable carrier, and the rolling bearings supporting the planetary gears enter and exit the oil bath in the casing by the rotation of the carrier. In the gear device, a planetary gear device characterized in that a rolling bearing whose rolling elements are hollow rollers is used as the rolling bearing. The inner ring gear provided in the casing and meshed with the plurality of planetary gears, and the sun gear meshed with the ring gear and rotatably arranged in a concentric position. A speed increasing planetary gear device in which a carrier serves as an input section and the sun gear serves as an output section. A step-up gear for wind power generator comprising the planetary gear device according to claim 1. A rolling bearing that supports a planetary gear of a planetary gear device rotatably on a carrier and enters and exits an oil bath by the rotation of the carrier, wherein the rolling element is a hollow roller.

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