JP5537471B2 - Power transmission device - Google Patents

Description

The present invention is particularly so in the power transmission device of a wind power plant, relates to a suitable power transmission equipment for application to apparatus which may excessive load is input to the time.

  Patent Document 1 discloses a speed reducer used for yaw control of a nacelle (power generation chamber) of a wind power generation facility or pitch control of a wind turbine blade.

  Since wind power generation equipment is installed in a natural environment, it sometimes receives turbulent winds and gusts.

  In Patent Document 1, when an excessive torque exceeding a set value is input from the wind turbine blade side, the slip coupling is operated to interrupt the power transmission of the drive system and prevent the drive system from being overloaded. The technology is disclosed. This slip coupling is not supposed to be used as it is after it slips, and it is equipped with a sensor that detects slipping, indicating that the maintenance work of the slip coupling should be performed at the next maintenance stop. It is devised to be.

US2007-0098549A1 (Claim 1, paragraph [0015])

  However, the maintenance of wind power generation systems is not so frequent, and therefore systems that require maintenance work once slipped are extremely inconvenient, resulting in the threshold for slip initiation being a huge typhoon or the like. It must be set to a very high level that will activate for the first time. In other words, the basic drive system must be durable enough to continue operation without breaking until such an overload is applied. It was forced to enlarge.

  The present invention has been made to solve such a conventional problem, and particularly in a power transmission device that is suitably applied in a situation where a large load may be temporarily applied, the size of the device is naturally reduced. The object is to reduce the load of maintenance work and effectively protect the entire apparatus without increasing the size.

According to the present invention, in the power transmission device that transmits power between the first member and the second member, the first member has a hollow portion, and an outer diameter of the second member is the hollow of the first member. by setting the slightly larger size than the inner diameter of the section, and the first member and the second member is fitted with an interference fit, and the inner periphery and the said hollow portion of said first member first When the excessive torque exceeding a predetermined value is applied to at least one surface of the outer periphery of the two members, the slip is stopped when the excessive torque disappears, and the slip is stopped again between the first member and the second member. The power transmission device is subjected to a surface treatment for transmitting an original torque to be performed , the first member and the second member are accommodated in the casing, and the first member and the second member are accommodated in the casing. A window to confirm that the slid With the structure that has been formed is obtained by solving the above problems.

  In the case of a safety device that slides when an excessive torque exceeding a predetermined value is applied to the power transmission system, as in the case of the slip coupling described above, “slip” is an emergency evacuation operation to protect the device. If it slips once, it was thought that the original torque transmission could no longer be achieved. Actually, even in the above-mentioned Patent Document 1, it is not assumed that the slip coupling is repeatedly used as it is without maintenance work even after slipping.

  However, according to the inventor's many test results, when a specific surface treatment is performed on at least one of the inner periphery of the hollow portion of the first member and the outer periphery of the second member, an interference fit is performed. a) Slip occurs when an excessive torque exceeding a predetermined value is applied; b) When the excessive torque disappears, the slip stops and the power transmission device is again between the first member and the second member. It was possible to obtain the knowledge that the two effects of repeatedly transmitting the original torque that should be performed in the above are obtained. This is because the actual transmission torque capacity can be secured again even when a test that intentionally adds excessive torque and intentionally generates forced slip is repeated multiple times. This is based on the fact that the surface treatment was confirmed to exist (detailed later).

  According to the present invention, the excessive torque is directly applied to each element in the apparatus by allowing a part of the temporarily input energy to escape without being transmitted without increasing the size of the entire apparatus. Can be prevented and can be automatically restored.

  According to the present invention, it is possible to effectively protect the entire apparatus while reducing the load of maintenance work without increasing the size of the apparatus.

FIG. 1 is an overall cross-sectional view of a speed reducer for wind power generation equipment that employs a power transmission device according to an example of an embodiment of the present invention. Front view of wind power generation equipment to which the speed reducer is applied The perspective view which shows a mode that the said reduction gear is integrated in the nacelle of the said wind power generation equipment. Cross-sectional view of the main part showing the structure of the yaw drive device of the wind power generation facility Sectional drawing of the principal part of the power transmission device which concerns on an example of embodiment of this invention applied to the reduction gear of FIG. Whole sectional drawing of the joint unit which concerns on an example of embodiment of this invention The whole sectional view of the reduction gear of wind power generation equipment to which the power transmission device concerning an example of other embodiments of the present invention is applied. The whole sectional view of the reduction gear of wind power generation equipment to which the power transmission device concerning an example of other embodiments of the present invention is applied. The whole sectional view of the reduction gear of wind power generation equipment to which the power transmission device concerning an example of other embodiments of the present invention is applied.

  Hereinafter, a power transmission device according to an example of an embodiment of the present invention will be described in detail.

  First, an outline of a wind power generation facility to which the power transmission device is applied will be described.

  With reference to FIGS. 2 and 3, the wind power generation facility 10 includes a nacelle (power generation chamber) 12 at the uppermost portion of the cylindrical support 11. The nacelle 12 includes a yaw driving device 14 and a pitch driving device 16. The yaw driving device 14 is for controlling the turning angle of the entire nacelle 12 with respect to the cylindrical column 11, and the pitch driving device 16 is for controlling the pitch angle of the three windmill blades 20 attached to the nose cone 18. belongs to.

  In this embodiment, since the present invention is applied to the yaw driving device 14, the yaw driving device 14 will be described here.

  The yaw drive device 14 includes four reduction gears G1 to G4 with a motor 22 and an output pinion 24, and one turning internal gear 28 that meshes with each output pinion 24. Each reduction gear G1-G4 is being fixed to the predetermined position by the side of the main body of nacelle 12, respectively. Referring also to FIG. 4, the turning internal gear 28 with which the output pinions 24 of the reduction gears G <b> 1 to G <b> 4 are meshed is fixed to the cylindrical column 11 side, and the inner ring of the yaw bearing 30 is Is configured. The outer ring 30 </ b> A of the yaw bearing 30 is fixed to the main body 12 </ b> A side of the nacelle 12. In addition, the code | symbol 25 of FIG.

  With this configuration, when the output pinions 24 are simultaneously rotated by the motors 22 of the reduction gears G1 to G4, the output pinions 24 mesh with the internal gears 28 while being centered on the internal gear 28 (see FIG. 3). Revolve against. As a result, the entire nacelle 12 can be swung around the center 36 of the internal gear 28 fixed to the cylindrical column 11. Thereby, the nose cone 18 can be directed in a desired direction (for example, the windward direction), and the wind pressure can be efficiently received.

  Since the speed reducers G1 to G4 have the same configuration, the speed reducer G1 will be described here.

  Referring to FIG. 1, a reduction gear G1 includes a motor 22, an orthogonal gear mechanism 40, a parallel shaft reduction mechanism 42, and a final stage reduction mechanism 44 arranged in this order in a casing Ca on a power transmission path. The casing Ca can be separated into a high speed side casing body 46 and a low speed side casing body 48.

  Hereinafter, description will be made in the order on the power transmission path. The motor shaft 50 of the motor 22 also serves as the input shaft of the orthogonal gear mechanism 40. The orthogonal gear mechanism 40 includes a hypoid pinion 52 formed by cutting directly at the tip of the motor shaft 50, and a hypoid gear 54 that meshes with the hypoid pinion 52, and changes the rotation direction of the motor shaft 50 to a right angle direction. The hypoid gear 54 is fixed to the intermediate shaft 56. A spar pinion 58 of the parallel axis reduction mechanism 42 is directly formed on the intermediate shaft 56. The parallel shaft speed reduction mechanism 42 includes the spar pinion 58 and a spar gear 60 that meshes with the spar pinion 58. The spur gear 60 is fixed to the hollow shaft 62 via a key 61. The hollow shaft 62 is connected to a joint shaft 66 via a key 64.

  The joint shaft 66 is press-fitted to the bush 68. In this embodiment, the power transmission device T1 according to the present invention is applied to a joint portion between the joint shaft 66 and the bush 68. The configuration of the joint shaft 66 and the bush 68 will be described in detail later.

  The final stage reduction mechanism 44 rotates integrally with the bush 68 (of the final stage reduction mechanism 44), two eccentric bodies 74 provided on the input shaft 72, and is eccentric via the eccentric body 74. Two oscillating external gears 76 and an internal gear 78 in which the external gears 76 are internally meshed are provided. The two external gears 76 have an eccentric phase shifted by exactly 180 degrees, and rotate and rotate while maintaining an eccentric state in directions away from each other. The internal gear 78 is integrated with the low-speed casing body 48. The internal teeth of the internal gear 78 are each constituted by a cylindrical outer pin 78A. The number of internal teeth of the internal gear 78 (the number of external pins 78A) is one more than the number of external teeth of the external gear 76. An inner pin 80 is loosely fitted to the external gear 76. The inner pin 80 is integrated with the output flange 82, and the output flange 82 is integrated with the output shaft 84 of the reduction gear G1. In this embodiment, since the internal gear 78 is integrated with the low-speed casing body 48, when the input shaft 72 of the final stage reduction mechanism 44 rotates, the external gear 76 swings via the eccentric body 74, Relative rotation (rotation) of the external gear 76 with respect to the internal gear is extracted from the output shaft 84 via the inner pin 80 and the output flange 82. The output pinion 24 is fixedly coupled to the output shaft 84 via a spline 86, and the output pinion 24 is meshed with the turning internal gear 28 (FIGS. 3 and 4) already described. It is said that.

  Here, the configuration of the power transmission device T1 including the joint shaft 66 and the bush 68 will be described in detail with reference to FIG.

  The bush 68 includes a hollow portion 68A and corresponds to the first member in the present invention. The joint shaft 66 has a tip portion 66B fitted in the hollow portion 68A and corresponds to the second member of the present invention. The outer diameter d1 of the distal end portion 66B of the joint shaft 66 is slightly larger than the inner diameter D1 of the hollow portion 68A of the bush 68 (specifically, the portion of the hollow portion 68A into which the distal end portion 66B of the joint shaft 66 is fitted). The size is set. That is, the joint shaft 66 and the bush 68 have a dimensional relationship that is an interference fit. In this embodiment, the joint shaft 66 and the bush 68 are fitted by press-fitting.

  A plurality of ring-shaped grooves 66A (four in this embodiment) are formed in the tip portion 66B of the joint shaft 66. An adhesive is applied to the outer periphery of the tip portion 66B of the joint shaft 66 including the inside of the groove 66A. More specifically, the adhesive is uniformly applied to the outer periphery of the tip end portion 66B of the joint shaft 66, and the adhesive slid down when the bushing 68 is press-fitted has a gap in the groove 66A. Filled with no. In this embodiment, as the adhesive, a commercially available adhesive (for example, trade name: Loctite 242, 243 manufactured by Henkel Japan Co., Ltd.) used for preventing loosening of screws of the vibrating device is used.

  With this configuration, when the joint shaft 66 and the bush 68 are fitted by press-fitting (an interference fit), slipping occurs when excessive torque exceeding a predetermined value is applied, and when the excessive torque disappears In addition, it is possible to realize a configuration in which the torque up to the predetermined value can be transmitted between the joint shaft 66 and the bush 68 again. In the present invention, “slipping stops when the excessive torque disappears” does not necessarily mean that “slipping stops immediately” when the input torque becomes a predetermined value or less. And includes the concept that “slipping stops when the input torque becomes lower than a predetermined value to some extent”.

  In the inventor's test, with the above configuration, it is actually possible to return to a state where a torque equivalent to the initial transmittable torque can be transmitted every time the excessive torque disappears even after slipping 100 times or more. Has been confirmed. Also, the degree of interference fit, the number of grooves 66A, the axial width W1, the axial distance L1 and depth (not shown), the surface roughness of parts other than the grooves, the adhesive strength of the adhesive, and the hardness (or elastic modulus) It has also been confirmed that the predetermined value, which is a threshold value to start sliding, and the degree of return after sliding once change by changing the above. At least the surface treatment that can return to a state where torque up to a predetermined value can be transmitted is possible by these adjustments.

  According to further tests by the inventor, when an appropriate surface treatment is applied, when the slip occurs due to excessive torque exceeding the predetermined value, while the slip continues, the predetermined It has also been confirmed that the torque transmission corresponding to the value is maintained and that the return after the slippage can be completely performed. This characteristic means that, for example, when applied to a power transmission device of a wind power generation facility, it can brake the movement of the nacelle to some extent while releasing excessive torque caused by the wind, and it can automatically return when slipping stops. This is a preferable characteristic.

  The mechanism of this occurrence of slip → maintenance of torque transmission corresponding to a predetermined value and stoppage of slip → return to a state where normal torque transmission (below the predetermined value) can be performed is achieved by an appropriate “surface treatment”. It is considered that the pressure can be applied to the three members 68, the joint shaft 66, and the adhesive so as to generate a limit of the stress that can be transmitted within the range in which the elastic deformation is possible. In short, i) “transmission” of the torque is possible while the “stress” sufficient to catch the input torque is generated at the three joints, and ii) the input torque is If it exceeds the stress that can occur in the joint, it will not be possible to transmit any more torque and `` slip '' will occur, but the stress of elastic deformation can maintain torque transmission even if slipping, Further, iii) if the deformation actually occurring at the joint portion between the first member and the second member is within the range of elastic deformation at the joint portion (if the level is not yet plastically deformed) ), A mechanism can be inferred that when the excessive torque disappears, the initial torque transmission state can be restored. In any case, a surface treatment is performed so that slippage occurs when excessive torque is applied, torque transmission corresponding to a predetermined value is maintained, and when the excessive torque disappears, the slippage stops and the initial torque transmission state can be restored. It is true that it is feasible.

  In this sense, the “surface treatment applied to at least one surface of the inner periphery of the hollow portion of the first member and the outer periphery of the second member” in the present invention is a machine such as a groove in the first member and the second member itself. In addition to a narrowly-defined surface treatment that forms an uneven surface, the concept includes a broadly-defined surface treatment that affects the connected state or elastically deformed state of the first member and the second member, such as a process of applying an adhesive.

  In other words, the surface treatment of the present invention can be regarded as “a surface treatment in which both the first member and the second member are fitted with an interference fit within the range of elastic deformation”. That is, the conventional interference fit such as press-fitting does not have the idea of “sliding repeatedly”. Therefore, in order to realize strong integration by an easy work as much as possible (usually the first having a hollow portion). The member) is made softer than the other and is fitted with “plastic deformation”. Therefore, once it starts to slide, the transmission torque decreases rapidly (torque transmission corresponding to the torque value at the time of sliding cannot be maintained). Also, once slipping, excessive torque is removed and even if slipping stops, the original strong integrated state cannot be restored.

  Whether or not the engagement is an interference fit within the range of elastic deformation is, for example, whether each of the first member and the second member returns to the original state when “fitting” and “detaching” are repeated. Can be judged by no. When “fit within the range of elastic deformation” is performed, both the inner periphery of the first member and the outer periphery of the second member are both separated when the engagement is repeated. Return to the inner and outer diameters before mating each time.

  As shown in FIG. 6, the joint shaft 66 according to this embodiment has a connecting portion 66 </ b> D with the hollow shaft 62. The connecting portion 66D is formed with a key groove 66C in which the key 64 described above for connecting the joint shaft 66 and the hollow shaft 62 is received. Further, the bush 68 has a connecting portion 68 </ b> C into which the input shaft 72 of the final stage reduction mechanism 44 is fitted on the side opposite to the hollow shaft. A spline 68B for connecting the bush 68 and the input shaft 72 (spline 70 thereof) is formed in the connecting portion 68C. That is, the joint shaft 66 and the bush 68 constitute a pair (one set) of “joint units 67”. The effects obtained by configuring the joint unit 67 will be described later.

  Returning to FIG. 1, in this embodiment, the joint shaft 66 and the bush 68 are accommodated in an independent joint casing 46A. A window 46A1 is formed in the joint casing 46A, and the joint shaft 66 and the bush 68 can be observed from the outside of the joint casing 46A. The joint shaft 66 and the bush 68 are marked with a “mark” so as to straddle both the joints 66 and 68. By observing whether the position of the mark is shifted from the window 46A1, the joint shaft 66 and the bush 68 can be confirmed just in case.

  Next, the operation of the reduction gear G1 including the power transmission device T1 according to this embodiment will be described.

  The rotation of the motor shaft 50 of the motor 22 is decelerated at the first stage by meshing of the hypoid pinion 52 and the hypoid gear 54 of the orthogonal gear mechanism 40, and simultaneously the direction of the rotation shaft is changed by 90 degrees and transmitted to the intermediate shaft 56 of the parallel shaft reduction mechanism 42. Is done.

  The rotation of the intermediate shaft 56 is decelerated by the meshing of the spar pinion 58 and the spar gear 60 and is transmitted to the hollow shaft 62 by the key 61. The rotation of the hollow shaft 62 is transmitted to the joint shaft 66 through the key 64 fitted in the key groove 66C of the joint shaft 66. The rotation of the joint shaft 66 is transmitted to the bush 68 by fitting with the adhesive filled in the groove 66A by press fitting, and the final stage through the spline 68B on the inner peripheral side of the bush 68 and the spline 70 on the outer periphery of the input shaft. This is transmitted to the input shaft 72 of the speed reduction mechanism 44.

  When the input shaft 72 of the final stage reduction mechanism 44 rotates, the external gear 76 swings and rotates via the eccentric body 74 (while inscribed in the internal gear 78), so that the meshing position with the internal gear 78 is sequentially changed. A phenomenon of shifting occurs. As a result, every time the input shaft 72 of the final stage reduction mechanism 44 rotates once, one external gear swings and the phase is shifted by one tooth with respect to the internal gear 78 (in a fixed state). (Rotating components are generated). By taking out this rotation component to the output shaft 84 side through the inner pin 80 and the output flange 82, deceleration by the final stage reduction mechanism 44 is realized. The rotation of the output shaft 84 is transmitted to the output pinion 24 through the spline 86. Since the output pinion 24 meshes with the internal gear 28 for turning, and the internal gear 28 is fixed to the cylindrical column 11 side, the nacelle 12 is eventually opposed to the cylindrical column 11 by reaction. Rotates itself horizontally.

  Here, it is assumed that a huge torque for turning the nacelle 12 by a gust or the like acting on the windmill blade 20 is input from the output pinion 24 side of the reduction device G1 for yaw driving. This huge “external load” drives the final stage reduction mechanism 44 of the reduction gear G1 from the reverse side, and rotates the bush 68 via the splines 70 and 68B. If the rotational torque is within the expected range (below a predetermined value), no slip occurs between the bush 68 and the joint shaft 66, and the torque is further transferred to the parallel shaft gear mechanism 42 side of the reduction gear G1. It is transmitted and finally received by a brake device (not shown) attached to the motor 22. As a result, the movement of the nacelle 12 due to the wind is reliably braked. In this case, no abnormality occurs in each part of the reduction gear G1.

  However, if a torque exceeding a predetermined value is input from the output pinion 24 side (bush 68 side) (there is a possibility that an abnormality may occur in each part of the reduction gear G1), the bush 68 and the joint shaft Slip occurs with 66. Therefore, a part of the excessive torque from the output pinion 24 side can be released here. Therefore, although the nacelle 12 rotates horizontally according to the wind, it is possible to prevent damage to the motor and the gear mechanism (at this time, by braking the torque corresponding to the predetermined value transmitted to the motor 22 side, the corresponding braking force Can be applied to the nacelle 12). Further, when the storm stops, the bush 68 and the joint shaft 66 automatically return to the original torque transmission state, so that the wind power generation can be continued as it is.

  According to the power transmission device T1 according to the present embodiment, since a sensor and an electrical control system are not required for overtorque countermeasures, reliability is ensured even in bad weather conditions where the control system is easily damaged by lightning strikes or flooding. High operation is possible.

  The window 46A1 formed in the joint casing 46A can confirm whether or not the joint shaft 66 and the bush 68 have slipped between the previous maintenance and the current maintenance. Can be done.

  Here, in this embodiment, the power transmission device T1 according to the present invention is embodied in the form of a “joint unit 67”. For this reason, it is possible to confirm and adjust the torque transmission characteristics and torque recovery characteristics as set at the manufacturing stage in the factory, and even if a defect occurs, it will not be possible on site (in a narrow nacelle). There is an advantage that it is only necessary to replace it as “one part”.

  It is also possible to “select” a joint unit 67 that actually has the most appropriate torque characteristics for the reduction gear G1 from a plurality of joint units based on the torque characteristics obtained in the actual slip test in the factory. It is.

  Furthermore, when mass-selling the joint unit (67) alone (not limited to wind power generation applications), the actual torque is classified by classifying the individual joint units (67) based on the actually measured torque characteristics. It is also possible to differentiate products based on characteristics.

  In any case, since such adjustment and selection can be executed in the factory, it is possible to obtain the “joint unit 67” that is easy to handle and has extremely high reproducibility and reliability of torque characteristics.

  However, the power transmission device T1 according to the present invention is not necessarily required to have such a “joint unit” type. For example, the power transmission device T1 can be directly incorporated into a shaft such as an input shaft, an intermediate shaft, or an output shaft of a reduction gear, thereby further saving. Space can also be achieved. An example is shown in FIG.

  In the power transmission device T2 according to this embodiment, the hollow shaft 102 of the parallel shaft gear mechanism 100 of the reduction gear G10 functions as the first member (having the hollow portion 102A) of the power transmission device T2 according to the present invention. The input shaft 106 of the step reduction mechanism 104 is caused to function directly as the second member. As shown in an enlarged view in a circle B in FIG. 7, the input shaft 106 has a plurality of (seven in this example) grooves 106A similar to the joint shaft 66 in the previous embodiment. Is filled with an adhesive. The basic configuration regarding the groove 106A, the adhesive, and the press-fitting is the same as in the previous embodiment.

  In this embodiment, as shown in an enlarged view in a circle A, a roller 110 having the same diameter as the outer pin 108A constituting the inner teeth of the internal gear 108 extends coaxially with the outer pin 108A. The roller 110 functions as a bearing for the output flange 112. Since other configurations are the same as those of the previous embodiment, only the same or similar parts in FIG. 7 are denoted by the same reference numerals, and redundant description is omitted.

  According to the structure according to this embodiment, there is no space occupied as the “joint unit” in the previous embodiment, the size of the entire apparatus can be made more compact, and the number of parts can be reduced.

  In addition, the apparatus in which the power transmission device according to the present invention is incorporated is not limited to the reduction gear as described above. FIG. 8 shows an example of still another embodiment of the present invention.

  In this embodiment, the power transmission devices T3 and T4 according to the present invention are incorporated in a reduction gear G20 constituted by a two-stage swinging inscribed planetary gear mechanism. The basic structure of the planetary gear mechanisms 120 and 124 at the front stage and the rear stage is the same as that of the final stage speed reduction mechanism 44 in the previous embodiment.

  In this embodiment, the output flange 122 of the planetary gear mechanism 120 at the front stage functions as the first member (having the hollow portion 122A) of the power transmission device T3 according to the present invention, and the input shaft of the planetary gear mechanism 124 at the rear stage. 126 is made to function as the second member. As shown in an enlarged view in a circle A in FIG. 8, a plurality of grooves 126A are formed in the input shaft 126 of the planetary gear mechanism 124 at the rear stage, and an adhesive is formed on the outer periphery of the input shaft 126 including the inside of the grooves 126A. Is applied to the input shaft 126 and the output flange 122 by press-fitting.

  In this embodiment, the output pinion 128 of the rear planetary gear mechanism 124 functions as the first member (having the hollow portion 128A) of the power transmission device T4 according to the present invention and the output of the rear planetary gear mechanism 124. The shaft 130 functions as the second member. A plurality of grooves 130A are also formed in the output shaft 130 of the planetary gear mechanism 124 at the subsequent stage, and an adhesive is applied to the outer periphery of the output shaft 130 including the inside of the groove 130A, and then the output shaft 130 and the output pinion 128 are applied. Is press-fitted with an interference fit.

  Even in such a reduction gear, it is possible to perform the surface treatment capable of torque return after slip intended in the present invention by such a configuration, and the effects inherent in the present invention can be obtained accordingly.

  Also in this embodiment, compared to the first embodiment, the entire apparatus can be made more compact and the number of parts can be reduced because there is no space occupied as a “joint unit”.

  FIG. 9 shows an example of still another embodiment of the present invention.

  In this embodiment, the power transmission devices T5 and T6 according to the present invention are incorporated into a reduction gear G30 constituted by four stages of simple planetary gear mechanisms 141 to 144.

  That is, in this embodiment, the output carrier 150 of the first stage simple planetary gear mechanism 141 functions as the first member (having the hollow portion 150A) of the power transmission device T5 according to the present invention, and the second stage simple planetary gear. The input shaft 152 of the mechanism 142 is caused to function as the second member. A plurality of grooves (not shown) are formed in the input shaft 152 of the second stage simple planetary gear mechanism 142, and an adhesive is applied to the outer periphery of the input shaft 152 including the inside of the grooves, and then the input shaft 152 152 and the output carrier 150 are press-fitted and fitted with an interference fit.

  In this embodiment, the output carrier 156 of the second stage simple planetary gear mechanism 142 functions as the first member (having the hollow portion 156A) of the power transmission device T6 according to the present invention, and the third stage simple The input shaft 158 of the planetary gear mechanism 143 is made to function as the second member. A plurality of grooves (not shown) are formed on the input shaft 158 of the third stage simple planetary gear mechanism 143, and an adhesive is applied to the outer periphery of the input shaft 158 including the inside of the grooves, and then the input shaft 158 and the output carrier 156 are press-fitted with an interference fit.

  The present invention can also be applied to the reduction gear G30 having such a configuration, and corresponding effects can be obtained. In this embodiment as well, the output pinion 160 of the last stage planetary gear mechanism 144 is the same as the power transmission device T4 according to the previous embodiment, instead of the application position or in addition to the application position. While functioning as the first member according to the invention (having the hollow portion 160A), the output shaft 162 of the last stage planetary gear mechanism 144 may function as the second member.

  Also in this embodiment, an effect peculiar to the present invention can be obtained, and since it is directly incorporated in the power transmission path, it is possible to prevent an increase in the number of parts and to keep the entire apparatus compact. it can.

  Thus, in the present invention, there is no particular limitation as to what part of which drive system the present invention is applied to. However, as in the previous embodiments, it is more preferable that the part does not rotate at the same rotational speed as the motor (is rotated at a high speed). This is because it is not preferable that high-speed sliding occurs when slipping occurs.

  Regarding the method of surface treatment, the important point is that when excessive torque exceeding a predetermined value is applied to at least one of the inner periphery of the hollow portion of the first member and the outer periphery of the second member, the excessive torque If the surface treatment for transmitting the original torque up to the predetermined value is again applied between the first member and the second member when the power is lost, the specific processing is particularly the example in the above embodiment. It is not limited. The surface treatment that forms the grooves exemplified in the above embodiment is easy to manufacture, has little mechanical damage when slipped, and can form a holding space when using an adhesive or the like together. Although it is preferable, examples of the process other than the process of forming the groove include shot peening and knurling. In addition, barrel polishing using a large polishing stone is also effective. These “treatments for forming mechanical irregularities on the surface of the member” are particularly suitable as an example of treating the surface other than the grooves in combination with the formation of the grooves. Of course, only these methods may be employed instead of the grooves. Further, such mechanical unevenness (including a groove) may be formed on the inner periphery of the hollow portion of the second member (not on the outer periphery of the first member). In particular, the power transmission device T4 in FIG. 8 should be formed on the inner periphery where the torque to be handled is large. Of course, you may form in both a 1st member and a 2nd member. Such “treatment for forming mechanical irregularities on the surface of the member” is effective from the viewpoint of securing a high predetermined value while maintaining the difficulty of the “fitting operation” at a lower level.

  On the other hand, a surface treatment that affects the connection state and elastic deformation state of the first member and the second member, such as application of an adhesive, may function very effectively for the present invention. In addition to the application of adhesives, this includes the application of highly viscous fillers and the inclusion of hard films and sheets. For example, the use of an oil that can be expected to have a particularly high shear stress among so-called traction drive oils may be effective in applications where the sliding time is relatively long, for example. The surface treatment according to the present invention is preferably combined with mechanical irregularities such as grooves, but may be only application of an adhesive or the like.

  Further, the present invention can be realized by selecting a material and devising a manufacturing method without using any adhesive. The inventor actually conducted various tests in a power transmission device that can be used as a reduction device for yaw drive of a wind power generation facility according to the above-described configuration. For example, bearing steel (for example, JIS G) is used as the first member. 4805 SUJ2), which has been ground after quenching and tempering, and carburized steel (for example, SCM420 of JIS G 4053) as the second member, after carburizing, quenching and tempering By adopting a barrel-polished one and press-fitting within the range of elastic deformation, a high reproduction result was obtained at least several tens of times. In this test example, specifically, the inner diameter of the first member and the outer diameter of the second member can be press-fitted within the range of elastic deformation of both the first and second members, and the wind power generation equipment As a speed reducer for the yaw drive device, a torque (predetermined value) to be slid was set. Note that the “predetermined value” is 400 Nm to 600 Nm in the case of the yaw drive device of the above embodiment, considering the reduction ratio of the final stage reduction mechanism 44 and the like, but is set to 500 Nm in this test.

  In this repeated test, A) Even when an excessive torque of various magnitudes is applied, while the slip is occurring, a torque transmission of approximately 500 Nm can be maintained and secured as the “torque corresponding to the predetermined value”; B) When the application of excessive torque is stopped and a normal level torque of less than 500 Nm is applied, it is possible to return to a state where power can be transmitted without slipping. It has been confirmed.

  In the above embodiment, a simple and low-cost “press-fit” fitting is employed to achieve an interference fit. However, when a stronger fitting (stronger torque transmission) is required, Fitting by shrink fitting or cold fitting is effective.

  If necessary, the conditions for effectively realizing the function of the present invention are as follows: (1) The first member and the second member can be fitted by an interference fit within the range of elastic deformation; (2) During normal driving It is possible to set the torque that starts to slip within a range that is larger than the maximum torque to be transmitted and smaller than the torque that may damage the device as a “predetermined value”; It means that it only has to be selected. From this point of view, if the material itself already has an appropriate surface state that can satisfy both of the above conditions (1) and (2), even if the surface treatment in the broad sense already described is not performed separately, In some cases, the function of the present invention can be realized only by selecting a material. For example, although expensive, materials containing tungsten, tungsten (such as cemented carbide or high-speed steel), materials containing titanium, etc., can be produced by simply manufacturing the required shape using a normal manufacturing method. 1) In some cases, it is possible to obtain characteristics that can satisfy the conditions (2). Of course, measures such as a seizure prevention treatment that does not cause seizure for as long as possible even if it slides repeatedly may be made in parallel.

  In the above embodiment, an example in which the present invention is applied to a reduction device for yaw drive is shown. However, the present invention is also applicable to a reduction device for a pitch drive device, for example. Can be similarly applied in applications other than wind power generation, particularly in applications that are likely to be temporarily overloaded. In other words, if it is estimated from the aspect of the effect of the invention, for example, an application where excessive torque is likely to be generated when a foreign object is bitten, such as a conveyor for mines and a conveyor for chips of processing machines. Can be applied. Further, the present invention can also be applied to applications such as turning a deck crane, driving a shield excavator drill, and turning a construction excavator. That is, even in these applications, the work is suddenly large from the work object side due to the influence of wind, the influence of the inertial force of heavy objects, or the collision with obstacles or underground rocks. This is because a situation in which a strong torque is temporarily received from the load side by receiving a reaction force can be formed. In the present invention, it can be applied to such applications, and the same effects can be obtained.

  In addition, for the purpose of the present invention, according to the present invention, “slip when excessive torque exceeding a predetermined value is applied, and when the excessive torque disappears, the slip stops and the first member and the second member again. The term “performs the original torque transmission that should be performed in the power transmission device” should be interpreted as follows.

  That is, “slip when excessive torque exceeding a predetermined value is applied” is not necessarily required to transmit a torque corresponding to the predetermined value during the occurrence of the slip, and is equivalent to the predetermined value. Only the torque smaller than the torque transmitted in the normal time may be transmitted.

  In addition, as already described, “slipping stops when the excessive torque disappears” means that “slipping immediately stops” when the input torque is not more than the predetermined value. Instead, it includes the concept that “slipping stops when the input torque is lowered to some extent below a predetermined value”.

  Furthermore, “perform the original torque transmission that should be performed in the power transmission device between the first member and the second member again” does not necessarily require that 100% torque return be ensured, This means that it is only necessary to return to a state where the torque necessary for driving the driving object of the power transmission device can be transmitted. More specifically, for example, the “predetermined value (sliding torque)” may change by repetition. That is, in the present invention, the “predetermined value” may be set in a range that is larger than the maximum transmission torque assumed during normal driving and smaller than the transmission torque that may damage the device. As long as it is possible to return to the “predetermined value” that falls within this range (after the slide stops), the “predetermined value” itself may be changed by repeating the slip. For example, in the yaw drive device of a wind power generation facility as exemplified in the embodiment, the set value that causes slipping is sufficiently large with respect to the torque transmitted by the output of a normal motor. However, the nacelle can be driven and turned by the torque from the motor side without any problem even if the torque is slightly lower than the initial torque. If the nacelle can be driven / turned without any problem in the yaw drive device, it may be considered that the state has been returned to the state of “performing the original torque transmission to be performed again in the power transmission device”.

  In addition, in relation to the word “again”, the number of times of return is greatly influenced by the application. In applications where the frequency of occurrence of slip itself is not so high, such as a yaw drive device of a wind power generation facility as exemplified in the embodiment, the first member is reattached even if it slips several times. If it can be restored to the extent that it can transmit the original torque that can drive the turning of the nacelle with the second member, it can function as a yaw drive device with virtually no trouble, and the operation of the wind power generation facility can be performed. Can continue. However, in applications where excessive torque is generated relatively frequently, such as the generation of excessive torque when a foreign object is caught in a conveyor, it is considered that recovery is required, for example, several hundred times or in some cases several thousand times. It is done. In short, in relation to the use of the power transmission device (frequency of occurrence of slipping), if the normal operation of the power transmission device can be continued for a number of times that can be continued without any major trouble, the “first member and the first again” It may be considered that the original torque transmission that should be performed in the power transmission device is performed between the two members.

10 ... wind power generation equipment 11 ... cylindrical support 12 ... nacelle (power generation room)
DESCRIPTION OF SYMBOLS 14 ... Yaw drive device 16 ... Pitch drive device 18 ... Nose cone 20 ... Windmill blade 22 ... Motor 24 ... Output pinion 66 ... Joint shaft (2nd member)
66A ... groove 68 ... bush (first member)

Claims (11)

In the power transmission device that transmits power between the first member and the second member,
The first member has a hollow portion;
By setting the outer diameter of the second member to be slightly larger than the inner diameter of the hollow portion of the first member, the first member and the second member are fitted with an interference fit, and ,
When the excessive torque exceeding a predetermined value is applied to at least one surface of the inner periphery of the hollow portion of the first member and the outer periphery of the second member, the slip occurs when the excessive torque disappears. Stop and apply a surface treatment to perform the original torque transmission to be performed in the power transmission device between the first member and the second member again ,
The first member and the second member are housed in a casing; and
A window for confirming that the first member and the second member have slipped is formed in the casing. In claim 1,
The surface that maintains torque transmission corresponding to the predetermined value between the first member and the second member when the surface treatment is applied with an excessive torque exceeding the predetermined value and the slip is generated. A power transmission device characterized by being a process. In claim 2,
The power transmission device according to claim 1, wherein the surface treatment is a surface treatment in which both the first member and the second member are fitted with the interference fit within a range of elastic deformation. In any one of Claims 1-3,
The power transmission device, wherein the surface treatment includes a process of forming mechanical irregularities on at least one surface of an inner circumference of the hollow portion of the first member and an outer circumference of the second member. In claim 4,
The process of forming the mechanical unevenness includes a process of forming a ring-shaped groove on at least one surface of the inner periphery of the hollow portion of the first member and the outer periphery of the second member. Power transmission device. In any one of Claims 1-5,
The power transmission device, wherein the surface treatment includes a process of applying an adhesive to at least one surface of an inner periphery of the hollow portion of the first member and an outer periphery of the second member. In any one of Claims 1-3,
Surface in which the surface treatment is used in combination with a process of applying an adhesive to a process of forming the mechanical irregularities on at least one surface of the inner periphery of the hollow portion of the first member and the outer periphery of the second member. A power transmission device characterized by being a process. In any one of Claims 1-7,
The interference transmission is realized by press-fitting. A power transmission device for wind power generation equipment having the power transmission device according to any one of claims 1 to 8 as a part of its own driving force transmission system. In the power transmission device that transmits power between the first member and the second member,
The first member has a hollow portion;
By setting the outer diameter of the second member to be slightly larger than the inner diameter of the hollow portion of the first member, both the first member and the second member are within the range of elastic deformation. And it is fitted with an interference fit that slides when excessive torque exceeding the specified value is applied ,
The first member and the second member are housed in a casing; and
A window for confirming that the first member and the second member have slipped is formed in the casing. In claim 10 ,
At least one surface of the inner periphery of the hollow part of the first member and the outer periphery of the second member is subjected to a surface treatment for fitting with an interference fit of the strength. Power transmission device.

Images