Shaft member, planetary gear unit, and planetary gear device

Abstract

The outer peripheral surface (27) of the shaft member (22) slides with the inner peripheral surface (24) of the planetary gear member (21). The shaft member (22) has a sliding portion (26), an opening portion (41), a connection channel portion (42), and a groove portion (43). The sliding section (22) is provided on the outer peripheral side of the main body section (25) and has an outer peripheral surface (27) that slides on the inner peripheral surface (24), and the outer peripheral surface (27) is divided in the circumferential direction into a first region (31) and a second region (32) that are preset. The opening (41) opens in a first region (31) on the outer peripheral side of the sliding part (26). The groove section (43) is provided so as to be recessed radially inward from the outer peripheral surface (27), connects the opening section (41) and at least one end of the sliding section (26) in the axial direction, and a groove end section (48), which is an end on the opposite side from the opening section (41), opens on an outer wall (29) of the end of the sliding section (26) in the axial direction.

Description

Technical Field

[0001] The present embodiment relates to a shaft member, a planetary gear unit, and a planetary gear device. Background Art

[0002] A planetary gear system is installed between the input and output sides of a power source, decelerating or accelerating the input drive force and transmitting it to the output. This system includes a planetary gear unit between a so-called sun gear and an internal gear, which revolves circumferentially while meshing with these gears. The planetary gear unit comprises a planetary gear member with external teeth and a shaft member that rotates relative to the internal gear member.

[0003] In recent years, while the devices generating driving force have become increasingly large, planetary gear systems are being required to be even lighter. Consequently, research is underway to replace conventional rolling bearings with plain bearings for supporting the planetary gear members and shaft members in planetary gear systems. While the use of plain bearings can achieve a smaller planetary gear system, it also presents the problem of increased torque density and greater load on the sliding parts.

[0004] This planetary gear device, due to its unique structure, is characterized by limiting the areas where high loads are applied during operation between the planetary gear members of the planetary gear unit and the shaft member supporting them. Specifically, regardless of how their positions change with rotation, high-load areas and low-load areas are always located within specific ranges on the inner circumference of the planetary gear member and the outer circumference of the shaft member, which slide against each other.

[0005] Therefore, lubrication between the planetary gear members and the shaft members is a crucial factor in planetary gear units. Patent Document 1 provides recessed and raised portions in the sliding areas between the planetary gear members and the shaft members. This facilitates the retention of lubricating oil in the recessed portions, and even when using sliding bearings, facilitates the formation of an oil film in areas where high loads are locally applied depending on operating conditions.

[0006] However, in the case of Patent Document 1, foreign matter that intrudes between the planetary gear member and the shaft member tends to remain in the recess, thereby hindering the formation of an oil film on the sliding portion. In particular, when using sliding bearings, in order to maintain the oil film formed by the lubricating oil between the inner circumferential surface of the planetary gear member and the outer circumferential surface of the shaft member, which form the sliding portion, it is necessary to prevent the intrusion of foreign matter. When foreign matter intrudes, it damages the sliding portion, which hinders the formation of an oil film on the sliding portion. As a result, there are problems such as heat adhesion and abnormal wear of the sliding portion between the planetary gear member and the shaft member. In addition, in the case of Patent Document 1, the grooves for supplying lubricating oil to the sliding portion are provided along the entire circumference, including the area where the applied load increases. Therefore, in Patent Document 1, the overall sliding area is reduced, resulting in an increase in the pressure of the oil film. There is also the risk of insufficient supply of lubricating oil at the axial end, the intrusion of foreign matter into the area where the applied load increases, and other factors that hinder the formation of the oil film.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent document 1: International Publication No. WO2021 / 058262. Summary of the Invention

[0010] Problems to be solved by the invention

[0011] Therefore, the purpose of this embodiment is to provide a shaft component, a planetary gear unit, and a planetary gear device that promote the discharge of foreign matter and form a stable oil film on the sliding part, thereby reducing heat sticking, abnormal wear, etc. and extending the service life.

[0012] Solutions for solving problems

[0013] The shaft component of the present embodiment for solving the above-mentioned problem slides with the inner peripheral surface of the planetary gear component, and the shaft component has a sliding portion, an opening portion, a connecting channel portion and a groove portion. The sliding portion is arranged on the outer peripheral side of the main body portion, and has an outer peripheral surface that slides with the inner peripheral surface, and the outer peripheral surface is divided into a predetermined first area and a second area outside the first area in the circumferential direction. The opening portion is opened in the first area on the outer peripheral side of the sliding portion. The connecting channel portion is inside the shaft component, connecting at least one end in the axial direction with the opening portion. The groove portion is arranged in a manner that is recessed radially inward from the outer peripheral surface, connecting the opening portion and at least one end in the axial direction of the sliding portion, and the groove end portion of the groove portion is open on the outer wall of the end portion in the axial direction of the sliding portion, and the groove end portion is the end portion of the groove portion on the opposite side of the opening portion.

[0014] Thus, in this embodiment, the lubricating oil is supplied to the opening portion via the connecting channel portion, and is supplied from the opening portion through the groove portion to the sliding portion between the inner peripheral surface and the outer peripheral surface. The lubricating oil flowing out of the opening portion is discharged from the groove end portion via the groove portion. Thus, even if foreign matter intrudes into the sliding portion between the inner peripheral surface and the outer peripheral surface, the foreign matter is facilitated to be discharged from the groove end portion together with the lubricating oil via the groove portion. In addition, in this embodiment, the opening portion is opened in the first area which is a pre-set area. Therefore, when constituting a planetary gear unit together with a planetary gear member, by making the first area correspond to the area where the load applied during sliding is smaller, an oil film is stably formed in the required portion between the inner peripheral surface and the outer peripheral surface.

[0015] Therefore, the discharge of foreign matter can be promoted, and a stable oil film can be formed on the sliding part, thereby reducing seizure, abnormal wear, etc., thereby extending the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic perspective view showing an example of the structure of a planetary gear device.

[0017] Figure 2 Schematic diagram showing a cross section along an axis of a planetary gear unit according to one embodiment.

[0018] Figure 3 It is from Figure 2 Schematic diagram of observation in the direction of arrow III.

[0019] Figure 4 It is from Figure 2 Schematic diagram of the shaft member of the first embodiment viewed in the direction of arrow IV.

[0020] Figure 5 It is a schematic diagram showing the outer peripheral surface of the shaft member according to the first embodiment developed in the circumferential direction.

[0021] Figure 6 This is a schematic perspective view showing a second region defined on the outer peripheral surface of the shaft member according to the first embodiment.

[0022] Figure 7 This is a schematic diagram showing a shaft member according to the first embodiment.

[0023] Figure 8 It is a schematic diagram showing a modified example of the shaft member of the first embodiment.

[0024] Figure 9 It is a schematic diagram showing a modified example of the shaft member of the first embodiment.

[0025] Figure 10 It is a schematic diagram showing a shaft member according to a second embodiment.

[0026] Figure 11 It is a schematic diagram showing a modified example of the shaft member of the second embodiment.

[0027] Figure 12 It is a schematic diagram showing a modified example of the shaft member of the second embodiment.

[0028] Figure 13 It is a schematic diagram showing a shaft member according to a third embodiment.

[0029] Figure 14 It is a schematic diagram showing a modified example of the shaft member of the third embodiment.

[0030] Figure 15 It is a schematic diagram showing a modified example of the shaft member of the third embodiment.

[0031] Figure 16 This is a schematic diagram showing an enlarged view of the vicinity of the narrowed portion in order to illustrate the shape of the narrowed portion in the shaft member according to the third embodiment.

[0032] Figure 17 This is a schematic diagram showing the relationship between the groove portion and the narrowed portion in the shaft member according to the third embodiment.

[0033] Figure 18 It is a schematic diagram showing a shaft member according to a fourth embodiment.

[0034] Figure 19 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0035] Figure 20 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0036] Figure 21 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0037] Figure 22 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0038] Figure 23 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0039] Figure 24 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0040] Figure 25 It is a schematic diagram showing an example of a shaft member according to another embodiment. DETAILED DESCRIPTION

[0041] Hereinafter, the embodiment will be described based on the accompanying drawings. In addition, in a plurality of embodiments, substantially the same components are marked with the same reference numerals and the description thereof is omitted. In this specification, the axial direction refers to the direction of the axis. Figure 1 The radial direction refers to the direction perpendicular to the axial direction. The circumferential direction refers to the direction parallel to the axis of rotation as shown in AA'. Figure 1 The circumferential direction with the axis as the center is shown as R-R'.

[0042] (Planetary Gear Unit)

[0043] Figure 1 FIG. 1 shows an example of a general planetary gear device 10. The planetary gear device 10 includes a first shaft member 11, a second shaft member 12, a sun gear 13, an internal gear 14, a planetary carrier 15, and a planetary gear unit 16. Figure 1 The gear components in the first and second figures are not shown with teeth for simplicity. The sun gear 13 is mounted on the first shaft member 11 and rotates integrally with the first shaft member 11. The sun gear 13 is a so-called external gear and has an external tooth portion 17 on the outer circumference. The internal gear 14 is a so-called internal gear and is formed in a circular ring shape with an internal tooth portion 18 on the inner circumference. The planetary carrier 15 is mounted on the second shaft member 12 and rotates integrally with the second shaft member 12.

[0044] The planetary gear unit 16 includes a planetary gear member 21 and a shaft member 22. The planetary gear member 21 is an externally toothed gear supported by the shaft member 22 for relative rotation. The planetary gear unit 16 is disposed between the sun gear 13 and the internal gear 14, meshing with both the sun gear 13 and the internal gear 14. At least one planetary gear unit 16 is provided circumferentially around the sun gear 13. The shaft member 22 of each planetary gear unit 16 is supported by the planetary carrier 15.

[0045] Thus, when the planetary carrier 15 rotates along with the second shaft member 12, which serves as the input shaft, this rotation is transmitted to the planetary gear unit 16. For example, by fixing the internal gear 14 so that it cannot rotate, the planetary gear unit 16 orbits about the sun gear 13. At this time, the planetary gear member 21 of the planetary gear unit 16 and the shaft member 22 supported by the planetary carrier 15 rotate relative to each other. Specifically, the planetary gear member 21 rotates in the direction opposite to the orbital direction of the planetary carrier 15 due to the orbital rotation of the planetary carrier 15. For example, if the planetary carrier 15 orbits clockwise, the planetary gear member 21 rotates counterclockwise. Therefore, the shaft member 22, which is fixed to the planetary carrier 15, rotates along with the planetary carrier 15, causing the planetary gear member 21 and shaft member 22 to rotate relative to each other. This causes the inner circumference of the planetary gear member 21 to slide against the outer circumference of the shaft member 22. As the planetary gear unit 16 orbits, the rotation is transmitted to the first shaft member 11, which serves as the output shaft, via the sun gear 13. Thus, the rotation input from the second shaft member 12 is accelerated and transmitted to the first shaft member 11 via the planetary gear device 10. In the above example, the second shaft member 12 is used as the input side, the first shaft member 11 is used as the output side, and the internal gear 14 is fixed to achieve acceleration. However, in the planetary gear device 10, any combination of the three elements, namely, the first shaft member 11, the second shaft member 12, and the internal gear 14, can be used, with any one of the three elements, namely, the first shaft member 11, the second shaft member 12, and the internal gear 14, used as the input side, any other element used as the output side, and the remaining element fixed.

[0046] (Planetary Gear Unit)

[0047] The planetary gear unit 16 used in the planetary gear device 10 will be described.

[0048] The planetary gear unit 16 of this embodiment includes the planetary gear member 21 and the shaft member 22 as described above. Figure 2 and Figure 3 As shown, the planetary gear member 21 is an externally toothed gear having an external tooth portion 23 on its outer circumference. It is formed in a cylindrical shape. The planetary gear member 21 has a cylindrical inner circumferential surface 24. The shaft member 22 is disposed within the inner circumference of the cylindrical planetary gear member 21. The planetary gear member 21 and the shaft member 22 rotate relative to each other. Therefore, the outermost surface of the shaft member 22 slides against the inner circumferential surface 24 of the planetary gear member 21.

[0049] (First embodiment of the shaft member)

[0050] like Figure 2As shown, the shaft member 22 of the first embodiment includes a main body 25 and a sliding portion 26. The main body 25 is formed into a solid or hollow shaft shape. The main body 25 is formed of an Fe-based material such as Fe or an Fe alloy. The sliding portion 26 is formed of a sliding alloy, resin, or the like, and is disposed on the outer periphery of the main body 25. In the first embodiment, an example in which the sliding portion 26 is formed of a sliding alloy is described. The sliding alloy used in the sliding portion 26 can be any alloy, such as a Cu-based, Al-based, or Sn-based alloy. The sliding portion 26 is formed on the outer periphery of the main body 25 by any method, such as press-fitting, build-up welding, or electroplating. When a resin is used, the sliding portion 26 can be made of various resins, such as fluorine-containing resin, POM (polyoxymethylene), PEEK (polyetheretherketone), or polyamide resin. In this case, the sliding portion 26 is formed on the outer periphery of the main body 25 by any method, such as spraying, printing, welding, or impregnation. Impregnation refers to a method in which a porous sintered material is impregnated with a resin. The sliding portion 26 has an outer peripheral surface 27 on its outer circumference. The outer peripheral surface 27 of the sliding portion 26 is slidable against the inner peripheral surface 24 of the planetary gear member 21. Specifically, the outer peripheral surface 27 of the shaft member 22, located on the outermost side of the sliding portion 26, is slidable against the inner peripheral surface 24 of the planetary gear member 21. The sliding portion 26 has an annular outer wall 28 and an outer wall 29 at its axial end portions. The sliding portion 26 may also have another layer, such as a resin coating, provided on its outer peripheral surface 27.

[0051] In the case of the first embodiment in which the shaft member 22 has the sliding portion 26, the entire axial length of the planetary gear member 21 is greater than the entire axial length of the sliding portion 26. Figure 2 As shown, the sliding portion 26 of the shaft member 22 is axially housed inside the planetary gear member 21. Thus, the outer walls 28 and 29 of the sliding portion 26 are located inside the axial ends of the planetary gear member 21.

[0052] like Figure 4 and Figure 5As shown, the outer circumferential surface 27 of the sliding portion 26 is circumferentially divided into a predetermined first region 31 and a predetermined second region 32. The first and second regions 31, 32 are adjacent to each other within a predetermined range along the circumference of the outer circumferential surface 27. When assembled in the planetary gear device 10, the planetary gear unit 16 orbits around the sun gear 13 while rotating in a direction opposite to the orbital direction, as described above. Due to the unique structure of the planetary gear device 10, the shaft member 22 always receives a large load from the planetary gear member 21 within a certain range when sliding against the planetary gear member 21 during operation of the planetary gear device 10. Specifically, when sliding against the planetary gear member 21, the shaft member 22 is divided into a main load portion 33, which receives a large load from the planetary gear member 21, and a secondary load portion 34, which receives a smaller load than the main load portion 33. Specifically, during operation of the planetary gear device 10, the shaft member 22 of the planetary gear unit 16 always receives a large load on the main load portion 33, and the range of this load remains largely unchanged even during rotation. In the first embodiment, the first region 31 defined on the outer peripheral surface 27 of the sliding portion 26 serves as the auxiliary load portion 34 , and the second region 32 serves as the main load portion 33 .

[0053] More specifically, Figure 5 This is a development diagram of the outer peripheral surface 27 developed in the circumferential direction. Figure 4 In FIG, the relative rotation direction between the planetary gear member 21 and the shaft member 22 is set to R, and the upper end side is set to 0° and the lower end side is set to 180° as a circumferential coordinate system. Figure 5 It is an expanded diagram at 90° in the circumferential direction. Figure 5 As shown, the first region 31 is mainly set in the range of 180° to 360° in the coordinate system, and the second region 32 is mainly set in the range of 0° to 180° in the coordinate system. More specifically, the second region 32, which serves as the main load portion 33, is set in the range of 0° to 180° in the coordinate system in such a manner that the center angle D is in the range of 0°<D<150° according to the characteristics of the planetary gear device 10. In this case, the center angle D of the second region 32, which serves as the main load portion 33, is preferably at least 30° or more. However, the second region 32, which serves as the main load portion 33, is not necessarily as Figure 4As shown in the example, the outer peripheral surface 27 is located near 90° in the coordinate system. That is, when the planetary gear member 21 and the shaft member 22 slide, due to the characteristics of the planetary gear device 10, the main load portion 33, which is subjected to a large load, is generated at any position within the range of 0° to 180° in the coordinate system. Therefore, the second region 32, which serves as the main load portion 33, is set within the range of 0° to 180° in the coordinate system, in an area where the central angle D is 0° < D < 150°, due to the characteristics of the planetary gear device 10. Furthermore, the area of ​​the outer peripheral surface 27 excluding the second region 32, which serves as the main load portion 33, forms the first region 31, which serves as the secondary load portion 34.

[0054] In addition, the second region 32 serving as the main load portion 33 is not limited to the Figure 4 、 Figure 5 ,as well as Figure 6 (A) is an example in which the second region 32 serving as the main load portion 33 is set parallel to the central axis of the shaft member 22. That is, as long as the second region 32 serving as the main load portion 33 is divided in the circumferential direction of the shaft member 22, the second region 32 may be divided into the second region 32 and the second region 32. Figure 6 As shown in FIG. (B), the second region 32 serving as the main load portion 33 is set to be inclined relative to the central axis on the outer peripheral surface 27 of the shaft member 22. Furthermore, the second region 32 serving as the main load portion 33 is not limited to being set over the entire axial length of the shaft member 22. Figure 6 (C) is set in the middle of the axial direction. Furthermore, the second region 32 which becomes the main load portion 33 is not limited to Figure 6 The one shown may be divided into two or more parts in the axial direction or the circumferential direction.

[0055] In addition to the above, Figures 2 to 5 as well as Figure 7 As shown, the shaft member 22 further includes an opening portion 41, a connecting channel portion 42, and a groove portion 43. The opening portion 41 opens in the first region 31 on the outer peripheral side of the sliding portion 26. That is, the opening portion 41 opens in the first region 31 on the outer peripheral surface 27 on the outermost peripheral side of the sliding portion 26. The connecting channel portion 42 is provided inside the shaft member 22 to connect at least one end portion of the shaft member 22 to the opening portion 41. The connecting channel portion 42 can not only be Figure 2 One end of the shaft member 22 is connected to the opening 41 as shown in the figure, and a structure in which both ends of the shaft member 22 are connected to the opening 41 can also be adopted. Lubricating oil supplied from a pump not shown flows through the connecting channel portion 42. When the planetary gear unit 16 is constructed, the lubricating oil is supplied to the sliding portion between the planetary gear member 21 and the shaft member 22. The lubricating oil is supplied to the opening 41 via the connecting channel portion 42. In the case of the first embodiment, as shown in FIG. Figure 2 and Figure 3As shown, the connecting channel portion 42 has a channel portion 45 extending in the axial direction and a channel portion 46 extending in the radial direction. Figure 2 and Figure 3 In the example shown, the connecting channel portion 42 may also be inclined relative to the axial direction or radial direction. In addition, the connecting channel portion 42 is not limited to the example in which the channel portion 45 and the channel portion 46 are connected from at least one end of the shaft member 22 to the opening portion 41. In other words, the connecting channel portion 42 may be connected to the opening portion 41 from the end of the shaft member 22 without being bent, or may have two or more bent portions.

[0056] The groove portion 43 is recessed radially inward from the outer peripheral surface 27 of the sliding portion 26. That is, the groove portion 43 is provided in a concave shape in the sliding portion 26. Figure 7 As shown, the groove portion 43 connects the opening portion 41 to at least one end portion of the sliding portion 26 in the axial direction. Thus, one end of the groove portion 43 is connected to the opening portion 41, and the other end has a groove end portion 48 located on the outer wall 29, which is an end portion of the sliding portion 26. Thus, the end portion of the groove end portion 48 opposite the opening portion 41 is open to the outer wall 29 of the sliding portion 26.

[0057] like Figure 4 and Figure 5 As shown, the opening 41 and the groove 43 provided in the shaft member 22 are provided in the secondary load portion 34 as the first region 31 of the sliding portion 26. Specifically, in the case of the first embodiment, the opening 41 and the groove 43 are provided Figure 4 That is, the opening 41 and the groove 43 are provided in the auxiliary load portion 34 on the side substantially opposite to the main load portion 33 in the radial direction of the shaft member.

[0058] The connecting passage 42 is connected to the discharge passage of an external pump (not shown). The pump (not shown) that pressurizes the lubricating oil supplies the lubricating oil via the connecting passage 42. The lubricating oil discharged from the pump (not shown) is supplied to the connecting passage 42 via the discharge passage (not shown). With this structure, the lubricating oil supplied to the opening 41 via the connecting passage 42 flows out from the opening 41 along the outer circumferential surface 27 of the sliding portion 26. Simultaneously, a portion of the lubricating oil flowing out of the opening 41 flows axially through the groove 43 and is discharged from the groove end 48 to the outside of the planetary gear unit 16. In other words, foreign matter that has intruded into the sliding portion between the inner circumferential surface 24 and the outer circumferential surface 27 is discharged from the groove end 48 along with the lubricating oil flowing out of the opening 41.

[0059] The cross-sectional area of ​​the groove portion 43 may be substantially the same as the cross-sectional area of ​​the connecting channel portion 42, or may be different from the cross-sectional area of ​​the connecting channel portion 42. In this case, the cross-sectional area of ​​the groove portion 43 is preferably as follows: Figure 8As shown, the cross-sectional area of ​​the groove portion 43 is smaller than that of the connecting passage portion 42. By making the cross-sectional area of ​​the groove portion 43 smaller than that of the connecting passage portion 42, the flow rate of the lubricating oil supplied from the connecting passage portion 42 to the groove portion 43 is reduced. By reducing the flow rate of the lubricating oil, the capacity of the pump (not shown) can be reduced, thereby achieving miniaturization of the pump.

[0060] Furthermore, the groove portion 43 may not only extend from the opening portion 41 toward the outer wall 29 as one end portion in the axial direction of the shaft member 22, but may also extend from the opening portion 41 toward the outer wall 29 as one end portion. Figure 9 As shown, the grooves 43 also extend toward the outer wall 28, which is the other end, that is, toward both sides. By providing the grooves 43 from the opening 41 toward each axial end, the lubricating oil flowing out of the opening 41 flows axially toward both sides along the outer circumferential surface 27 of the shaft member 22. Consequently, the lubricating oil can be more evenly supplied between the inner circumferential surface 24 of the planetary gear member 21 and the outer circumferential surface 27 of the shaft member 22.

[0061] A method for manufacturing the shaft member 22 of the first embodiment having the above-described structure will be described.

[0062] In the shaft member 22, the main body 25 is formed of, for example, an Fe-based material. When the main body 25 is formed, a sliding portion 26 is provided on the outer peripheral side of the main body 25. The sliding portion 26 is provided on the main body 25 using, for example, an alloy of the Cu-based, Al-based, Sn-based, etc. The sliding portion 26 can be provided by forming it into, for example, a circular ring shape and pressing the main body 25 toward the inner peripheral side or heat-pressing it. In addition, the sliding portion 26 can also be provided by surfacing an alloy on the outer peripheral side of the main body 25. By providing the sliding portion 26 by surfacing, relative movement between the main body 25 and the sliding portion 26 will not occur compared to pressing in. In addition, by providing the sliding portion 26 by surfacing, dimensional accuracy is also improved compared to pressing in. Furthermore, the sliding portion 26 can also be formed of resin.

[0063] In the shaft member 22, when the sliding portion 26 is provided on the main body 25, a connecting channel portion 42 is formed. The connecting channel portion 42 is formed by machining such as laser machining or cutting. One end of the connecting channel portion 42 becomes an opening portion 41 that opens on the outer peripheral surface 27 of the sliding portion 26. In the case of the first embodiment, the end of the connecting channel portion 42 on the opposite side of the opening portion 41 is opened at the end in the axial direction of the main body 25. When the opening portion 41 and the connecting channel portion 42 are formed, a groove portion 43 connected to the opening portion 41 is formed. The groove portion 43 is formed by laser machining or machining in the same manner as the connecting channel portion 42. The groove portion 43 is formed by cutting the sliding portion 26 from the outer peripheral surface 27 in the radial direction. In this case, the groove portion 43 can also reach the main body 25 in the depth direction.

[0064] When the processing of the groove portion 43 is completed, the surface of the sliding portion 26 is subjected to finish processing. The finish processing of the surface is carried out by, for example, polishing, cutting, etc. The sliding portion 26 is formed to be slightly larger than the original outer diameter and is polished to a predetermined specified size. The groove portion 43 is formed in consideration of the thickness of the sliding portion 26 removed by the polishing. The shaft member 22 is formed through the above process. In addition, after polishing, the sliding portion 26 may also be subjected to post-processing such as heat treatment in order to stabilize its performance. In addition, the sliding portion 26 may also be provided with one or more arbitrary layers, such as a covering layer, on the outer peripheral surface 27 other than the groove portion 43.

[0065] The operation of the planetary gear unit 16 and the planetary gear device 10 using the shaft member 22 of the first embodiment having the above-described structure will be described.

[0066] During operation of the planetary gear device 10, the planetary gear member 21 rotates relative to the shaft member 22 while being supported by the shaft member 22. Specifically, the outer circumferential surface 27 of the shaft member 22 of the planetary gear unit 16 slides against the inner circumferential surface 24 of the planetary gear member 21. A pump (not shown) pressurizes lubricating oil and supplies it to the opening 41 via a connecting passage 42 provided inside the shaft member 22. The lubricating oil flows out of the opening 41 and is thereby supplied to the sliding portion between the planetary gear member 21 and the shaft member 22. Furthermore, a portion of the supplied lubricating oil flows axially from the opening 41 through the groove 43. The lubricating oil flowing axially in the groove 43 flows outward from the groove end 48 toward the outside of the planetary gear unit 16. At this time, any foreign matter that has entered the space between the planetary gear member 21 and the shaft member 22 is moved toward the groove 43 along with the lubricating oil due to the relative rotation of the planetary gear member 21 and the shaft member 22, and is subsequently contained therein. Because the lubricating oil flows axially in the groove 43, foreign matter contained in the groove 43 is discharged along with the lubricating oil from the groove end 48 to the outside of the planetary gear unit 16. Consequently, foreign matter that has intruded between the planetary gear member 21 and the shaft member 22, or that has formed therebetween, is quickly discharged from the sliding portion to the outside of the planetary gear unit 16. As a result, the sliding portion 26 of the shaft member 22 is protected from damage and wear caused by foreign matter.

[0067] The shaft member 22 of the first embodiment described above includes a groove 43 in the sliding portion 26. Therefore, foreign matter that intrudes from various components of the planetary gear device 10 into the planetary gear unit 16 during operation is expelled from the groove end 48 along with the lubricating oil flowing through the groove 43. In other words, even if foreign matter intrudes into the sliding portion between the inner circumferential surface 24 and the outer circumferential surface 27, it is facilitated to be expelled from the groove end 48 along with the lubricating oil via the groove 43. Consequently, damage and wear of the sliding portion 26 caused by foreign matter can be avoided, and a stable oil film can be formed.

[0068] Furthermore, in the first embodiment, the opening 41 and the groove 43 are provided in the first region 31, which becomes the secondary load portion 34. In the secondary load portion 34, the load applied to the shaft member 22 during operation of the planetary gear device 10 is smaller than that of the main load portion 33. Therefore, even if the opening 41 and the groove 43 are formed in the secondary load portion 34, the oil film formation on the main load portion 33, where a stable oil film is required, is not hindered. Therefore, when constructing the planetary gear unit 16, while ensuring the supply of lubricating oil, a stable oil film is formed on the required portion between the inner circumferential surface 24 and the outer circumferential surface 27, that is, on the main load portion 33 where a large load is applied to the sliding portion 26. Therefore, a stable oil film can be formed on the main load portion 33, where a large load is applied, thereby reducing seizure, abnormal wear, and the like, and extending the life of the planetary gear member 21 and the shaft member 22.

[0069] Furthermore, in the first embodiment, the planetary gear member 21 and the shaft member 22 are supported for relative rotation by sliding bearings in the sliding portion 26 provided on the shaft member 22. This simplifies the structure and maintenance, and reduces weight, compared to, for example, rolling bearings. Consequently, when the planetary gear device 10 is applied to a wind turbine (not shown), for example, it can achieve weight reduction and improved durability while coping with the increased size and load associated with increased output.

[0070] (Second embodiment of the shaft member)

[0071] Figures 10 to 12 A shaft member 22 of a second embodiment is shown.

[0072] The groove portion 43 of the shaft member 22 of the second embodiment has a circumferential groove portion 51 and an axial groove portion 52. The circumferential groove portion 51 extends from the opening portion 41 along the circumference of the sliding portion 26. The axial groove portion 52 extends from the end side of the circumferential groove portion 51 opposite to the opening portion 41 along the axial direction of the sliding portion 26. In this way, the groove portion 43 can combine the circumferential groove portion 51 extending in the circumferential direction and the axial groove portion 52 extending in the axial direction. The axial groove portion 52 has a groove end portion 48 at the end portion on the opposite side to the circumferential groove portion 51. The position where the axial groove portion 52 is connected to the circumferential groove portion 51 is not limited to the end portion of the circumferential groove portion 51. That is, the axial groove portion 52 can be connected to the circumferential groove portion 51 at any position as long as it is between the opening portion 41 and the end portion of the circumferential groove portion 51.

[0073] In addition, the axial groove portion 52 can not only Figure 10 As shown, there is a groove end 48 on one side in the axial direction, and it is also possible to use Figure 11 and Figure 12 As shown in FIG. 4 , the groove portion 43 may have a structure with groove end portions 48 on both sides in the axial direction. Figure 12As shown, a structure is adopted in which a circumferential groove portion 51 is provided extending from the opening portion 41 to both sides in the circumferential direction, and an axial groove portion 52 is connected to the end side of the circumferential groove portion 51 .

[0074] In the second embodiment, the groove 43 includes a circumferential groove 51 extending circumferentially within the secondary load portion 34. This allows the lubricating oil flowing out of the opening 41 to be supplied to a wider area circumferentially of the shaft member 22. Furthermore, in the second embodiment, the total area of ​​the groove 43 is increased, enabling more reliable containment of foreign matter. In the second embodiment, the groove 43 is also provided within the secondary load portion 34. Therefore, the groove 43 does not interfere with the formation of an oil film on the primary load portion 33.

[0075] (Third embodiment of shaft member)

[0076] Figures 13 to 15 A shaft member 22 according to a third embodiment is shown.

[0077] The shaft member 22 of the third embodiment has a narrowing portion 55 between the opening portion 41 and the groove end portion 48. The cross-sectional area of ​​the narrowing portion 55 is smaller than the cross-sectional area of ​​the other parts of the groove portion 43. Therefore, the narrowing portion 55 narrows the flow of the lubricating oil flowing through the groove portion 43, reducing the flow rate of the lubricating oil flowing through the groove portion 43. By making the cross-sectional area of ​​the narrowing portion 55 smaller than the cross-sectional area of ​​the other parts of the groove portion 43, the flow rate of the lubricating oil flowing through the groove portion 43 depends on the cross-sectional area of ​​the narrowing portion 55. That is, by providing the narrowing portion 55, the flow rate of the lubricating oil is reduced regardless of the cross-sectional area of ​​the other parts of the groove portion 43. As a result, the capacity of the unillustrated pump that supplies the lubricating oil can be reduced. The end of the narrowing portion 55 on the opposite side of the groove end portion 48, that is, the end on the opening portion 41 side is as shown. Figure 13 As shown, in the groove portion 43 , there is a starting portion 56 where the cross-sectional area starts to change in a direction of decreasing.

[0078] The narrowed portion 55 extends beyond a range G from the groove end 48 toward the opening 41, which is 3% of the outer diameter of the sliding portion 26. Specifically, the range G extends from the groove end 48 toward the opening 41, which is 3% of the outer diameter of the sliding portion 26. Furthermore, the starting portion 56 of the narrowed portion 55 extends beyond this range G, toward the opening 41. By setting the narrowed portion 55 in this manner, even if the flow rate of lubricating oil is restricted by the narrowed portion 55, lubricating oil is adequately supplied between the inner circumferential surface 24 and the outer circumferential surface 27. Furthermore, by setting the range G of the narrowed portion 55 in this manner, foreign matter can be adequately expelled using the lubricating oil flowing through the groove 43.

[0079] In the narrowing portion 55, the portion where the cross-sectional area becomes extremely small may be any position as long as the starting portion 56 is closer to the opening portion 41 side than the range G. Specifically, Figure 16As shown in (A), the narrowed portion 55 is composed of a portion whose cross-sectional area becomes smaller at the top end of the groove portion 43. Figure 16 (B) and Figure 16 As shown in (C), the narrowing portion 55 may also be a tapered portion with a gradually decreasing cross-sectional area. Figure 16 As shown in (B), part of it is tapered, or it can be as shown in Figure 16 As shown in (C), the entire portion is tapered. Furthermore, the narrowing portion 55 only needs to reduce the cross-sectional area in a portion. Therefore, the narrowing portion 55 can be as shown in FIG. Figure 16 As shown in (D), the cross-sectional area of ​​the groove end portion 48 side becomes larger than the portion with the smallest cross-sectional area. Figure 16 When the groove portion 43 is inclined with respect to the axis of the shaft member 22 as shown in FIG. 5(E), the starting portion 56 of the narrowed portion 55 only needs to be located closer to the opening 41 than the range G.

[0080] The narrowed portion 55 only needs to include a portion having a smaller cross-sectional area than the other portions of the groove portion 43 as described above. Therefore, the depth of the narrowed portion 55, that is, the total length of the shaft member 22 in the radial direction is not limited. In other words, as long as the narrowed portion 55 has a smaller cross-sectional area than the other portions of the groove portion 43, it can be formed as shown in FIG. Figure 17 (A)~ Figure 17 The depth and cross-sectional shape are arbitrarily set as shown in (F).

[0081] In the third embodiment, the groove 43 includes a narrowed portion 55. This reduces lubricant oil consumption. Consequently, the performance required of the pump (not shown) supplying the lubricant oil can be reduced while maintaining the ability to remove foreign matter. Furthermore, in the third embodiment, by positioning the narrowed portion 55, the lubricant oil flow rate can be limited while still allowing sufficient lubrication of the sliding parts and the removal of foreign matter using the lubricant oil flowing through the groove 43.

[0082] (Fourth Embodiment of Shaft Member)

[0083] Figures 18 to 24 A shaft member according to a fourth embodiment is shown. Figures 18 to 24 Equivalent to Figure 5 The outer peripheral surface 27 is shown in a developed view.

[0084] At least a portion of the groove portion 43 of the shaft member 22 of the fourth embodiment is inclined relative to the axis of the shaft member 22. Figure 18 In the case of the example shown, the two axial grooves 52 are inclined relative to the axis of the shaft member 22. The two axial grooves 52 are substantially parallel. It is preferred that the inclination angles H1 and H2 of the axial grooves 52 are approximately 0° to 55°. Figure 18In the illustrated example, the sum of the circumferential angular area a and the angular area b is 300° or less, which is enough to be accommodated in the first area 31 serving as the auxiliary load portion 34 , that is, a+b≦300°.

[0085] exist Figure 19 In the case of the example shown, the two axial grooves 52 are inclined relative to the axis at different angles. Figure 19 In the example shown, the two axial grooves 52 are inclined approximately symmetrically with the axis passing through the opening 41 as the symmetry axis in the developed view. Figure 20 In the case of the example shown, two openings 41 are provided. Figure 20 In the example shown, the circumferential groove portion 51 is connected to the two opening portions 41, and its end portions are connected to the two axial groove portions 52. Figure 21 and Figure 22 In the example shown, the axial groove portion 52 is curved and inclined in the axial direction. The groove portion 43 can be formed as follows Figure 21 As shown in FIG. 4 , the groove 43 can be connected to the opening 41 via a circumferential groove 51. Figure 22 As shown, the circumferential groove portion 51 is not provided, but the inclined groove portion 43 is extended to both ends in the axial direction.

[0086] Furthermore, the groove 43 may also be Figure 23 and Figure 24 In this case, the shaft member 22 has four grooves 43 inclined relative to the axial direction. The four grooves 43 can be formed as follows. Figure 23 As shown in FIG, all of the grooves 43 are connected to the opening 41. Figure 24 As shown, the structure is connected to two or more openings 41.

[0087] In the fourth embodiment, at least a portion of the groove portion 43 is inclined relative to the axis of the shaft member 22. Specifically, at least one of the circumferential groove portion 51 and the axial groove portion 52 of the groove portion 43 is inclined relative to the axis of the shaft member 22. Alternatively, both the circumferential groove portion 51 and the axial groove portion 52 may be inclined relative to the axis of the shaft member 22. Thus, the groove portion 43 is provided in a large area of ​​the portion where the inner circumferential surface 24 and the outer circumferential surface 27 slide. Therefore, lubrication of the sliding portion with lubricating oil is fully achieved. Consequently, formation of a stable oil film and expulsion of foreign matter can be further achieved.

[0088] (Other Embodiments)

[0089] The present invention described above is not limited to the above-described embodiment, and various embodiments can be employed without departing from the spirit and scope of the present invention.

[0090] In the above-mentioned embodiments, the example in which the end portion of the connecting passage portion 42 opposite to the opening portion 41 is connected to the axial end portion of the shaft member 22 is described. However, the end portion of the connecting passage portion 42 opposite to the opening portion 41 is not limited to being connected to the axial end portion of the shaft member 22. For example, Figure 25 As shown, the structure is connected to the outer wall of the shaft member 22 in the axial direction.

Claims

1. A shaft member that slides with the inner peripheral surface of a planetary gear member, the shaft member comprising: Main body; a sliding portion, which is provided on the outer peripheral side of the main body and has an outer peripheral surface that slides with the inner peripheral surface, wherein the outer peripheral surface is divided into a predetermined first area and a second area outside the first area in the circumferential direction; an opening portion that opens in the first region on the outer peripheral side of the sliding portion; a connecting passage portion, which is provided inside the shaft member and has one end portion connected to the opening portion; as well as The groove portion is arranged in a manner recessed radially inward from the outer peripheral surface, connecting the opening portion with at least one end portion of the sliding portion in the axial direction, and the groove end portion of the groove portion is open on the outer wall of the end portion in the axial direction of the sliding portion, and the groove end portion is the end portion of the groove portion on the opposite side of the opening portion.

2. The shaft member according to claim 1, wherein The groove portion connects the opening portion and both axial end portions of the sliding portion.

3. The shaft member according to claim 1, wherein The groove portion is provided in the first region.

4. The shaft member according to claim 1, wherein When the sliding portion slides with the planetary gear member, the sliding portion is divided into a main load portion receiving a large load from the planetary gear member and a secondary load portion receiving a smaller load than the main load portion. The first region is the auxiliary load portion.

5. The shaft member according to claim 1, wherein The cross-sectional area of ​​the groove portion is different from the cross-sectional area of ​​the connecting channel portion.

6. The shaft member according to claim 1, wherein The groove portion includes a circumferential groove portion extending from the opening portion in a circumferential direction of the sliding portion, and an axial groove portion extending from an end portion of the circumferential groove portion opposite to the opening portion in an axial direction of the sliding portion.

7. The shaft member according to claim 6, wherein At least one of the circumferential groove portion and the axial groove portion is inclined with respect to the axial direction of the sliding portion.

8. The shaft member according to any one of claims 1 to 7, wherein The groove portion has a narrowed portion between the opening portion and the groove end portion, the narrowed portion having a smaller cross-sectional area than other portions.

9. The shaft member according to claim 8, wherein The narrowed portion is provided with the groove end portion as a starting point so as to extend beyond a range G, and the range G is 3% of the outer diameter of the sliding portion from the groove end portion toward the opening portion.

10. The shaft member according to claim 8, wherein The cross-sectional area of ​​the narrowed portion varies in the axial direction of the sliding portion.

11. A planetary gear unit comprising: The shaft member according to claim 1; and The planetary gear member is provided on the outer peripheral side of the shaft member.

12. A planetary gear device comprising: a first shaft member; a sun gear disposed on the first shaft member; The planetary gear unit according to claim 11, wherein the planetary gear unit meshes with the sun gear on the inner circumference side and meshes with the internal gear on the outer circumference side; as well as The planet carrier is connected to the second shaft member and is fixed with the shaft member of the planetary gear unit.

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