Planetary gear unit and planetary gear device

Abstract

The shaft member (22) has a sliding region (30), an opening portion (41), a connection channel portion (42), and a groove portion (43). The sliding region (30) forms, in the circumferential direction, a main load section (32) that bears a large load from the planetary gear member (21) and a sub-load section (31) that bears a smaller load than the main load section (32) on the outer circumferential surface (27) during sliding. The opening section (41) opens in the sub-load section (31). The groove (43) is provided so as to be recessed radially inward from the outer peripheral surface (27), extends from the opening (43) toward at least one end of the sliding region (30) in the axial direction, and has a groove end (48) on the side opposite the opening (43), the groove end (48) being located further outward in the axial direction than the inner peripheral surface (24) facing the groove end (48).

Description

Technical Field

[0001] The present embodiment relates to 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, has the following characteristics: The regions where high loads are applied during operation are limited between the planetary gear members of the planetary gear unit and the shaft member supporting them. Specifically, the regions where high loads are applied and the regions where low loads are applied are always located within specific ranges, regardless of any positional changes caused by rotation between the inner circumferential surfaces of the planetary gear members and the outer circumferential surface 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 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 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 seizure, abnormal wear, etc. and extending the service life.

[0012] Solutions for solving problems

[0013] In order to solve the above problems, the planetary gear unit of this embodiment includes: a planetary gear component; a sliding component having a cylindrical inner circumferential surface, arranged on the inner circumferential side of the planetary gear component, and formed of a bearing alloy; and a shaft component having an outer circumferential surface, the entire axial length of the outer circumferential surface being longer than that of the inner circumferential surface, and a portion of the axial direction of the outer circumferential surface facing the inner circumferential surface.

[0014] The shaft member has a sliding region, an opening portion, a connecting passage portion, and a groove portion.

[0015] The sliding area is formed on the outer peripheral surface. When sliding with the planetary gear member provided with the sliding member, a main load portion and a secondary load portion are formed on the outer peripheral surface along the circumferential direction. The main load portion receives a larger load from the planetary gear member, and the secondary load portion receives a smaller load than the main load portion. The opening portion is opened in the secondary load portion. The connecting channel portion is provided inside the shaft member, connecting at least one axial end portion to the opening portion. The groove portion is provided in a manner recessed radially inward from the outer peripheral surface, extending from the opening portion to at least one axial end portion side of the shaft member, and having a groove end portion on the opposite side of the opening portion, and the groove end portion is located outside compared to the opposing inner peripheral surface.

[0016] Thus, in this embodiment, lubricating oil is supplied to the opening via the connecting channel, and from the opening through the groove to the sliding portion between the inner and outer peripheral surfaces. Lubricating oil flowing out of the opening is discharged from the groove end via the groove. Thus, even if foreign matter intrudes into the sliding portion between the inner and outer peripheral surfaces, it is facilitated to be discharged from the groove end along with the lubricating oil. Furthermore, in this embodiment, when the opening and the planetary gear member together form a planetary gear unit, the opening is located in the secondary load portion, where the load applied during sliding is relatively small. This ensures a stable oil film in the required portion between the inner and outer peripheral surfaces that form the sliding portion.

[0017] Therefore, the discharge of foreign matter can be promoted, and a stable oil film can be formed on the sliding part, which can extend the service life by reducing heat seizure, abnormal wear, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic perspective view showing an example of the structure of a planetary gear device.

[0019] Figure 2 Schematic diagram showing a cross section along an axis of a planetary gear unit according to one embodiment.

[0020] Figure 3 It is from Figure 2 Schematic diagram of observation in the direction of arrow III.

[0021] Figure 4 It is from Figure 2 Schematic diagram of the shaft member of the first embodiment viewed in the direction of arrow IV.

[0022] 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.

[0023] 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.

[0024] Figure 7This is a schematic diagram showing a shaft member according to the first embodiment.

[0025] Figure 8 It is a schematic diagram showing a modified example of the shaft member of the first embodiment.

[0026] Figure 9 It is a schematic diagram showing a modified example of the shaft member of the first embodiment.

[0027] Figure 10 It is a schematic diagram showing a modified example of the shaft member of the first embodiment.

[0028] Figure 11 It is a schematic diagram showing a shaft member according to a second embodiment.

[0029] Figure 12 It is a schematic diagram showing a modified example of the shaft member of the second embodiment.

[0030] Figure 13 It is a schematic diagram showing a modified example of the shaft member of the second embodiment.

[0031] Figure 14 It is a schematic diagram showing a shaft member according to a third embodiment.

[0032] Figure 15 It is a schematic diagram showing a modified example of the shaft member of the third embodiment.

[0033] Figure 16 It is a schematic diagram showing a modified example of the shaft member of the third embodiment.

[0034] Figure 17 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.

[0035] Figure 18 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.

[0036] Figure 19 It is a schematic diagram showing a shaft member according to a fourth embodiment.

[0037] Figure 20 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0038] Figure 21 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0039] Figure 22 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0040] Figure 23It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0041] Figure 24 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0042] Figure 25 It is a schematic diagram showing a modified example of the shaft member according to the fourth embodiment.

[0043] Figure 26 It is a schematic diagram showing an example of a shaft member according to another embodiment. DETAILED DESCRIPTION

[0044] 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'.

[0045] (Planetary Gear Unit)

[0046] 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.

[0047] 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.

[0048] 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 members 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 members 21 rotate 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 members 21 rotate 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 members 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. Furthermore, in the above example, acceleration is achieved using the second shaft member 12 as the input side, the first shaft member 11 as the output side, and the internal gear 14 fixed. 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 configured such that any one of the three elements, namely, the first shaft member 11, the second shaft member 12, and the internal gear 14, serves as the input side, any other element serves as the output side, and the remaining element is fixed.

[0049] (First embodiment)

[0050] The planetary gear unit 16 used in the planetary gear device 10 will be described.

[0051] The planetary gear unit 16 of the first embodiment has the planetary gear member 21 and the shaft member 22 as described above. In addition, the planetary gear unit 16 of the first embodiment has the sliding member 23 on the inner peripheral side of the planetary gear member 21. Figure 2 and Figure 3As shown, the planetary gear member 21 is an externally toothed gear with a tooth portion 211 provided on the outer circumference, and is formed in a cylindrical shape. The sliding member 23 is formed of, for example, a sliding alloy or resin, and is integrally provided on the inner circumference of the planetary gear member 21. In the first embodiment, an example in which the sliding member 23 is formed of a sliding alloy is described. The sliding alloy used in the sliding member 23 can be any alloy, such as a Cu-based, Al-based, or Sn-based alloy. The sliding member 23 is formed in an annular shape and is provided on the inner circumference of the planetary gear member 21 by any method, such as press-fitting, overlay welding, or plating. When using a resin, the sliding member 23 can be made of, for example, a fluorine-containing resin, POM (polyoxymethylene), PEEK (polyetheretherketone), or polyamide resin. In this case, the sliding member 23 is formed on the inner circumference of the planetary gear member 21 by any method, such as spraying, printing, welding, or impregnation. Impregnation refers to, for example, impregnating a porous sintered material with resin. The annular sliding member 23 has an inner circumferential surface 24 on the radially inner side. The sliding member 23 may be provided with another layer such as a coating layer formed of resin on the surface of the sliding alloy, that is, the inner peripheral surface 24 .

[0052] The shaft member 22 is provided on the inner circumference side of the cylindrical sliding member 23. The shaft member 22 is formed into a solid or hollow shaft shape. The shaft member 22 is formed of an Fe-based material such as Fe or Fe alloy. In the case of the first embodiment, as shown in FIG. Figure 2 As shown, the shaft member 22 includes a main body 25 and a large diameter portion 26. The shaft member 22 has an outer peripheral surface 27 on the outer peripheral side of the large diameter portion 26. The planetary gear member 21 and the shaft member 22 rotate relative to each other. Therefore, the outer peripheral surface 27 of the outermost layer of the shaft member 22 slides against the inner peripheral surface 24 of the sliding member 23. The outer diameter of the large diameter portion 26 is larger than the outer diameter of the main body 25. As a result, the shaft member 22 has an annular outer wall 28 and an outer wall 29 at the ends on both sides of the large diameter portion 26 along the axial direction.

[0053] In the case of the first embodiment in which the sliding member 23 is provided on the inner circumference of the planetary gear member 21, the entire axial length of the large diameter portion 26 of the shaft member 22 is greater than the entire axial length of the sliding member 23. In other words, the entire axial length of the outer circumference 27 of the shaft member 22 is greater than the entire axial length of the inner circumference 24 of the sliding member 23. Therefore, as Figure 2 As shown, outer peripheral surface 27 formed by large diameter portion 26 protrudes axially outward from inner peripheral surface 24 formed by sliding member 23. Thus, outer walls 28 and 29 of sliding member 22 are located outward from the axial ends of sliding member 23.

[0054] The outer peripheral surface 27 of the shaft member 22 protrudes further outward in the axial direction than the inner peripheral surface 24 formed by the sliding member 23. Therefore, the outer peripheral surface 27 of the shaft member 22 faces the inner peripheral surface 24 of the sliding member 23 in a portion of the axial direction. A sliding area 30 that slides in the direction of the inner peripheral surface 24 is formed in the portion of the outer peripheral surface 27 of the shaft member 22 that faces the inner peripheral surface 24. Figure 4 As shown, the sliding region 30 is circumferentially divided into a secondary load portion 31 and a primary load portion 32. The secondary load portion 31 and the primary load portion 32 are adjacent to each other within a predetermined range along the circumference of the outer peripheral 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 relative to the sliding member 23 integral with the planetary gear member 21 during operation of the planetary gear device 10. Specifically, the sliding region 30 of the shaft member 22 is divided into the primary load portion 32, which receives a large load from the planetary gear member 21, and the secondary load portion 31, which receives a smaller load than the primary load portion 32, when sliding relative to the sliding member 23 integral with the planetary gear member 21. Specifically, the shaft member 22 of the planetary gear unit 16 always receives a large load at the main load portion 32 during operation of the planetary gear device 10 , and even if it rotates, the range of the load hardly changes.

[0055] More specifically, Figure 5 This is a development diagram of the outer peripheral surface 27 developed in the circumferential direction. Figure 4 In the figure, the relative rotation direction between the planetary gear member 21 and the shaft member 22 is set to R, and as a circumferential coordinate system, the upper end side is set to 0° and the lower end side is set to 180°. Figure 5 It is an expanded diagram at 90° along the circumferential direction. Figure 5 As shown, the auxiliary load portion 31 is mainly set in the range of 180° to 360° in the coordinate system, and the main load portion 32 is mainly set in the range of 0° to 180° in the coordinate system. More specifically, the main load portion 32 is set in the range of 0° to 180° in the coordinate system in such a way that the center angle D becomes within 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 main load portion 32 is preferably at least 30°. Here, the main load portion 32 is not necessarily as Figure 4As shown in the example, the main load portion 32 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 32, which is subjected to a large load, is generated at any position within the range of 0° to 180° in the coordinate system. Therefore, within the range of 0° to 180° in the coordinate system, the main load portion 32 is set in the region where the central angle D is 0° < D < 150°, based on the characteristics of the planetary gear device 10. Furthermore, the area of ​​the outer peripheral surface 27 other than the main load portion 32 serves as the secondary load portion 31.

[0056] In addition, the main load portion 32 is not limited to Figure 4 、 Figure 5 ,as well as Figure 6 (A) is an example of setting it parallel to the central axis of the shaft member 22. That is, as long as it is divided in the circumferential direction of the shaft member 22, the main load portion 32 can also be as follows Figure 6 As shown in FIG. (B), the main load portion 32 is set to be inclined relative to the central axis on the outer peripheral surface 27 of the shaft member 22. Furthermore, the main load portion 32 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. Figure 6 The one shown may be divided into two or more parts in the axial direction or the circumferential direction.

[0057] 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 is opened on the auxiliary load portion 31 in the outer peripheral side of the shaft member 22. That is, the opening portion 41 is opened in the auxiliary load portion 31 in the outer peripheral surface 27 as the outermost peripheral side of the shaft member 22. The connecting channel portion 42 is provided inside the shaft member 22 and connects 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 area 30 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 the figure, the lubricating oil is supplied to the sliding area 30 between the planetary gear member 21 and the shaft member 22. Figure 2 and Figure 3 As 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.

[0058] The groove portion 43 is recessed radially inward from the outer peripheral surface 27 of the large diameter portion 26 of the shaft member 22. That is, the groove portion 43 is provided in a concave shape in the large diameter portion 26. Figure 7 As shown, the groove portion 43 extends from the opening portion 41 toward at least one axial end of the sliding member 23. Thus, one end of the groove portion 43 is connected to the opening portion 41, and the end opposite the opening portion 41 includes a groove end portion 48. The groove end portion 48 is located axially outward relative to the inner circumferential surface 24 of the sliding member 23. Thus, the end of the groove end portion 48 opposite the opening portion 41 faces axially outward of the sliding member 23.

[0059] The opening 41 and the groove 43 provided on the shaft member 22 are as follows. Figure 4 and Figure 5 Specifically, in the case of the first embodiment, the opening 41 and the groove 43 are provided at the auxiliary load portion 31 of the shaft member 22. Figure 4 That is, the opening 41 and the groove 43 are provided in the auxiliary load portion 31 on the side substantially opposite to the main load portion 32 in the radial direction of the shaft member 22 .

[0060] 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 large-diameter 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 area 30 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.

[0061] 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.

[0062] Furthermore, the groove portion 43 may not only extend from the opening portion 41 toward one end portion in the axial direction of the shaft member 22, but may also extend from the opening portion 41 toward one end portion. Figure 9 As shown, the grooves 43 also extend toward the other end, that is, toward both sides. By providing the grooves 43 at each axial end, the lubricating oil flowing out of the opening 41 flows along the outer circumferential surface 27 of the shaft member 22 toward both axial ends. Consequently, the lubricating oil can be more evenly supplied to the sliding area 30 between the outer circumferential surface 27 of the shaft member 22 and the inner circumferential surface 24 of the planetary gear member 21.

[0063] Furthermore, the groove end portion 48, which is the end portion of the groove portion 43 on the opposite side to the opening portion 41, is not limited to Figures 7 to 9 The example of reaching the outer wall 29 is shown. That is, the groove end 48 can also be as shown. Figure 10 As shown, it does not reach the outer wall 29. Figure 2 As shown, the outer peripheral surface 27 provided on the large diameter portion 26 of the shaft member 22 extends to the outside of the axial end of the sliding member 23. Therefore, even if the groove end 48 Figure 10 As shown, it does not reach the outer wall 29 and is located outside the sliding area 30. Therefore, even if the groove end 48 does not reach the outer wall 29, the lubricating oil flowing into the groove end 48 can flow out of the groove portion 43 to the outside of the planetary gear unit 16.

[0064] A method for manufacturing the shaft member 22 of the first embodiment having the above-described structure will be described.

[0065] In the shaft member 22, the main body 25 and the large diameter portion 26 are formed of, for example, an Fe-based material. In the shaft member 22, when the main body 25 and the large diameter portion 26 are formed, 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. 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 axial end 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. Similar to the connecting channel portion 42, the groove portion 43 is also formed by laser machining or machining. The groove portion 43 is formed by cutting the large diameter portion 26 from the outer peripheral surface 27 in the radial direction.

[0066] After the groove 43 is finished, the surface of the large-diameter portion 26 is finished. This surface finishing is performed, for example, by polishing or cutting. The large-diameter portion 26 is formed slightly larger than its original outer diameter and polished to a predetermined size. The groove 43 is formed to account for the thickness of the large-diameter portion 26 removed by this polishing. The shaft member 22 is formed according to the above steps.

[0067] The operation of the planetary gear device 10 using the planetary gear unit 16 of the first embodiment having the above-described structure will be described.

[0068] When the planetary gear device 10 operates, the planetary gear member 21 rotates relative to the shaft member 21 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 sliding member 23 provided on 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 within 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 out of 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 through 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 foreign matter that has formed therebetween, is quickly discharged from the sliding area 30 to the outside of the planetary gear unit 16. As a result, the shaft member 22 is protected from damage and wear caused by foreign matter.

[0069] The planetary gear unit 16 of the first embodiment described above includes a groove portion 43 in the shaft member 22. Therefore, foreign matter that enters the planetary gear unit 16 from various components of the planetary gear device 10 during operation is discharged from the groove end portion 48 along with the lubricating oil flowing through the groove portion 43. In other words, even if foreign matter intrudes into the sliding area 30 between the inner circumferential surface 24 and the outer circumferential surface 27, it is facilitated to be discharged from the groove end portion 48 along with the lubricating oil via the groove portion 43. Consequently, damage and wear of the inner circumferential surface 24 and the outer circumferential surface 27 caused by foreign matter can be avoided, and a stable oil film can be formed.

[0070] Furthermore, in the first embodiment, the opening 41 and the groove 43 are provided in the auxiliary load portion 31. In the auxiliary load portion 31, 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 32. Therefore, even if the opening 41 and the groove 43 are formed in the auxiliary load portion 31, the formation of an oil film on the main load portion 32 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, an oil film is stably formed on the required portion between the inner peripheral surface 24 and the outer peripheral surface 27, that is, on the main load portion 32 where a large load is applied to the shaft member 22. Therefore, it is possible to form a stable oil film on the main load portion 32 where a large load is applied, thereby reducing heat seizure, abnormal wear, etc., and extending the life of the planetary gear member 21 and the shaft member 22.

[0071] Furthermore, in the first embodiment, the planetary gear member 21 and the shaft member 22 are supported for relative rotation by a sliding bearing in the sliding member 23 provided inside the planetary gear member 21. 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.

[0072] (Second embodiment)

[0073] Figures 11 to 13 A shaft member 22 of a second embodiment is shown.

[0074] 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 to the circumference of the shaft member 22. The axial groove portion 52 extends from the end portion of the circumferential groove portion 51 opposite to the opening portion 41 to the axial direction of the shaft member 22. 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 side opposite 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.

[0075] In addition, the axial groove portion 52 can not only Figure 11 As shown, there is a groove end 48 on one side in the axial direction, and it is also possible to use Figure 12 and Figure 13 As shown in FIG. 4 , the groove portion 43 may be formed as follows: Figure 13As shown, the circumferential groove portion 51 extends from the opening portion 41 to both sides in the circumferential direction, and the axial groove portion 52 is connected to the end side of the circumferential groove portion 51.

[0076] In the second embodiment, the groove 43 includes a circumferential groove 51 extending circumferentially within the secondary load-bearing portion 31. 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-bearing portion 31. Therefore, the groove 43 does not interfere with the formation of an oil film on the primary load-bearing portion 32.

[0077] (Third embodiment)

[0078] Figures 14 to 16 A shaft member 22 according to a third embodiment is shown.

[0079] 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 14 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.

[0080] The narrowed portion 55 is positioned so as to extend beyond the opening 41 by a range G from the location where it intersects the axial end of the sliding region 30 in the groove 43. The location where the groove 43 intersects the axial outer edge of the sliding region 30 is defined as the outer edge 57. The range G corresponds to a length from the outer edge 57 toward the opening 41 that is 3% of the outer diameter of the large diameter portion 26 of the shaft member 22, which forms the sliding region 30. In other words, the length of the range G formed from the outer edge 57 to the starting portion 56 corresponds to 3% of the outer diameter of the large diameter 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 narrowed portion 55 restricts the flow rate of lubricating oil, sufficient lubricating oil is 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, sufficient foreign matter removal is ensured by the lubricating oil flowing through the groove 43.

[0081] In the narrowing portion 55, as long as the starting portion 56 is closer to the opening portion 41 side than the range G, the portion with the smallest cross-sectional area may be at any position. Figure 17 As 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 17 (B) and Figure 17 As shown in (C), the narrowing portion 55 may also be a tapered portion with a gradually decreasing cross-sectional area. Figure 17 As shown in (B), part of it is tapered, or it can be as shown in Figure 17 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 17 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 17 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.

[0082] 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 in the radial direction of the shaft member 22 is not limited. In other words, as long as the narrowed portion 55 has a structure with a smaller cross-sectional area than the other portions of the groove portion 43, it can be formed as shown in FIG. Figure 18 (A)~ Figure 18 The depth and cross-sectional shape are arbitrarily set as shown in (F). Figure 10 When the groove portion 43 does not reach the outer wall 29 as shown in the example, the narrowed portion 55 can also be provided between the opening 41 and the groove end 48 .

[0083] In the third embodiment, the groove 43 includes a narrowed portion 55. This reduces lubricant oil consumption. As a result, 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 expelling foreign matter using the lubricant oil flowing through the groove 43.

[0084] (Fourth embodiment)

[0085] Figures 19 to 25 A shaft member according to a fourth embodiment is shown. Figures 19 to 25 Equivalent to Figure 5 The outer peripheral surface 27 is shown in a developed view.

[0086] 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 19 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 19 In the illustrated example, the sum of the angular area a and the angular area b in the circumferential direction is 300° or less, which is an extent to be accommodated in the auxiliary load portion 31 , that is, a+b≦300°.

[0087] exist Figure 20 In the case of the example shown, the two axial grooves 52 are inclined at different angles relative to the axis. Figure 20 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 development view. Figure 21 In the case of the example shown, two openings 41 are provided. Figure 21 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 22 and Figure 23 In the example shown, the axial groove portion 52 is curved and inclined in the axial direction. Figure 22 As shown in FIG. 4 , the groove 43 can be connected to the opening 41 via a circumferential groove 51. Figure 23 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.

[0088] Furthermore, the groove 43 may also be Figure 24 and Figure 25 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 24 As shown in FIG. 4 , all of the grooves 43 are connected to the opening 41. Figure 25 As shown, the structure is connected to two or more openings 41.

[0089] 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.

[0090] (Other Embodiments)

[0091] 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.

[0092] 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 26 As shown, the structure is connected to the outer wall of the shaft member 22 in the axial direction.

Claims

1. A planetary gear unit comprising: Planetary gear components; a sliding member provided on the inner peripheral side of the planetary gear member and having a cylindrical inner peripheral surface; and A shaft member having an outer peripheral surface, wherein the entire axial length of the outer peripheral surface is longer than that of the inner peripheral surface, and a portion of the axial direction of the outer peripheral surface faces the inner peripheral surface. The shaft member has: a sliding region formed on the outer peripheral surface, wherein when sliding with the sliding member provided on the planetary gear member, a main load portion and a secondary load portion are formed on the outer peripheral surface along the circumferential direction, the main load portion receiving a larger load from the planetary gear member, and the secondary load portion receiving a smaller load than the main load portion; an opening portion, which is opened in the auxiliary load 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, extends from the opening portion to at least one end side of the shaft member in the axial direction, has a groove end portion on the opposite side of the opening portion, and the groove end portion is located axially outward compared to the opposing inner peripheral surface.

2. The planetary gear unit according to claim 1, wherein: The groove portion extends from the opening portion toward both end portions of the shaft member in the axial direction.

3. The planetary gear unit according to claim 1, wherein: The groove portion is provided in the auxiliary load portion.

4. The planetary gear unit 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.

5. The planetary gear unit according to claim 1, wherein: The groove portion has: a circumferential groove portion extending from the opening portion in a circumferential direction of the shaft member; as well as An axial groove portion extends from the circumferential groove portion in the axial direction of the shaft member.

6. The planetary gear unit according to claim 5, wherein: At least either the circumferential groove portion or the axial groove portion is inclined with respect to the axial direction of the shaft member.

7. The planetary gear unit according to any one of claims 1 to 6, 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.

8. The planetary gear unit according to claim 7, wherein: The narrowed portion is provided from the groove end portion toward the opening portion so as to extend beyond a range G that is 3% of the outer diameter of the shaft member forming the sliding region.

9. The planetary gear unit according to claim 7, wherein: A cross-sectional area of ​​the narrowed portion varies in the axial direction of the shaft member.

10. A planetary gear device comprising: a first shaft member; a sun gear disposed on the first shaft member; One or more planetary gear units according to claim 1, which mesh with the sun gear on the inner circumference side and mesh 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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