Speed reducer and industrial machine

Abstract

To inhibit the enlargement of a lubrication region in a speed reducer including a sealing member.SOLUTION: A speed reducer 10 includes a case 20, a carrier 30, main bearings 15, and a sealing member 60. The carrier 30 is disposed at least partly inside the case 20. The main bearings 15 are disposed between the case 20 and the carrier 30. The sealing member 60 includes a first ring 61, a second ring 62, and a first elastic ring 63. The first ring 61 is annular and mounted to one of the case 20 and the carrier 30. The second ring 62 contacts the first ring 61 at an annular region. The first elastic ring 63 is compressed between the second ring 62 and the other of the case 20 and the carrier 30. The sealing member 60 is located at least partly in the same region as the main bearings 15 in a radial direction DR perpendicular to a rotation axis RA of the carrier 30 relative to the case 20.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a reducer and an industrial machine. [Background technology]

[0002] For example, as disclosed in Patent Document 1, an industrial machine including a reducer is known. The industrial machine is used outdoors. The reducer includes a case, a bearing disposed in the case, and a carrier disposed so as to be rotatable relative to the case via the bearing. The reducer has a lubrication region that stores oil for lubricating the bearing and the carrier. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6453880 Summary of the Invention [Problem to be solved by the invention]

[0004] The reducer disclosed in Patent Document 1 includes a seal member for sealing the lubrication area. The seal member includes a floating seal. By locating the seal member at a position away from the carrier and bearing, the lubrication area in the reducer is expanded and the amount of oil stored increases. The increased amount of oil stored increases the amount of oil used in the reducer and the weight of the reducer. The present invention aims to suppress the expansion of the lubrication area in a reducer that includes a seal member. [Means for solving the problem]

[0005] A reducer according to one embodiment of the present invention includes: Case and a carrier at least partially disposed within the case; a main bearing disposed between the cases; The seal member has an annular first ring attached to one of the case and the carrier, a second ring contacting the first ring in an annular area, and an elastic ring compressed between the other of the case and the carrier and the second ring, and is located at least partially in the same area as the main bearing in a radial direction perpendicular to the rotation axis of the case and the carrier.

[0006] An industrial machine according to one embodiment of the present invention includes: A drive unit including a reducer is provided, The reducer includes a case, a carrier at least partially disposed within the case, a main bearing disposed between the case and the carrier, and a seal member that seals between the case and the carrier, the seal member includes an annular first ring attached to one of the case and the carrier, a second ring contacting the first ring in an annular region, and an elastic ring compressed between the other of the case and the carrier and the second ring, The seal member is located in at least a partial area with the main bearing in a radial direction perpendicular to the rotational axis of the case and the carrier. [Effects of the Invention]

[0007] According to the present invention, it is possible to suppress the expansion of the lubrication area in a reducer including a seal member. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram for explaining an embodiment, and is a side view of an industrial machine. [Figure 2] FIG. 2 is a cross-sectional view of a reducer included in the industrial machine of FIG. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is an enlarged view of part A in FIG. 2, and is a cross-sectional view of the seal member. [Figure 5]FIG. 5 is a cross-sectional view showing a modified example of the sealing member. [Figure 6] FIG. 6 is a cross-sectional view showing another modified example of the sealing member. [Figure 7] FIG. 7 is a cross-sectional view showing yet another modified example of the sealing member. DETAILED DESCRIPTION OF THE INVENTION

[0009] An embodiment of the present invention relates to the following [1] to [9].

[0010] [1] Case and a carrier at least partially disposed within the case; a main bearing disposed between the case and the carrier; a first ring attached to one of the case and the carrier, a second ring in contact with an annular region of the first ring, and an elastic ring compressed between the other of the case and the carrier and the second ring, and a sealing member positioned at least partially in the same region as the main bearing in a radial direction perpendicular to the rotation axis of the case and the carrier.

[0011] [2] The reducer of [1], wherein the first ring has a thickness in the annular region that presses the second ring toward the elastic ring.

[0012] [3] The reducer of [1] or [2], wherein the contact surface between the second ring and the first ring is located inside the case.

[0013] [4] The first ring is disposed between the second ring and the main bearing in an axial direction parallel to the rotation axis, The reducer according to any one of [1] to [3], wherein the first ring includes a portion that is located in at least part of the same region as the main bearing in the axial direction.

[0014] [5] The first ring includes a first portion and a second portion connected to the first portion in the axial direction, the first portion is located in the same region as the main bearing in the axial direction, the second portion includes a portion located radially inward of the first portion, The reducer according to any one of [1] to [4], wherein the first ring contacts the second ring at the second portion.

[0015] [6] The reducer according to [5], wherein the length of the first portion in the radial direction is reduced at a connection portion with the second portion.

[0016] [7] The reducer of [5] or [6], wherein the first ring is disposed between the first part and the second part and includes an elastic part made of a material having a smaller Young's modulus than the material of the first part and the material of the second part.

[0017] [8] The carrier is at least partially disposed within the case with a gap between it and the case, on the radially outer side of a contact surface where the second ring and the first ring contact, The speed reducer according to any one of [1] to [7], wherein the gap includes a portion extending in the radial direction and a portion extending in an axial direction parallel to the rotation axis.

[0018] [9] A drive unit including a reducer is provided. The reducer includes a case, a carrier at least partially disposed within the case, a main bearing disposed between the case and the carrier, and a seal member that seals between the case and the carrier, the sealing member includes an annular first ring attached to one of the case and the carrier, a second ring in contact with an annular region of the first ring, and an elastic ring compressed between the other of the case and the carrier and the second ring, The seal member is positioned in at least a partial area with the main bearing in a radial direction perpendicular to the rotation axis of the case and the carrier.

[0019] An embodiment will be described below with reference to the drawings. In the drawings, the scale and dimensional ratios are appropriately exaggerated from those of the actual objects in order to facilitate illustration and understanding. Note that configurations shown in some drawings may be omitted in other drawings.

[0020] Terms such as "parallel," "orthogonal," and "identical" that specify shapes, geometric conditions, and their degrees are not limited to their strict meanings. These terms should be interpreted to include a range of degrees within which similar functions can be expected.

[0021] 1 to 5 are diagrams for explaining one embodiment. FIG. 1 is a side view of industrial machine 1. The illustrated industrial machine 1 is a construction machine. A construction machine is a machine used outdoors for construction work. The illustrated construction machine is a shovel. Unlike the illustrated example, the industrial machine 1 may also be a dump truck.

[0022] The industrial machine 1 shown in FIG. 1 includes a traveling device 2 and a rotating body 3 rotatably attached to the traveling device 2. The traveling device 2 is a device that allows the industrial machine 1 to travel. The traveling device 2 includes a drive device 4 that supplies driving force for the industrial machine 1 to travel. The illustrated drive device 4 supplies driving force by rotational motion about a rotation axis extending in a direction perpendicular to the plane of the page. The rotating body 3 includes a rotation device 5. The rotation device 5 supplies rotational force by rotational motion about a rotation axis extending in the vertical direction in the figure.

[0023] The driving device 4 shown in FIG. 1 includes a reducer 10. The reducer 10 reduces the speed of rotational motion from an input shaft and outputs the reduced speed. The driving device 4 may include a motor that rotates the input shaft. The reduced rotational motion is output from an output shaft of the reducer 10. In the industrial machine 1 shown in FIG. 1, the reducer 10 is applied to the driving device 4. The reducer 10 may also be applied to a slewing device 5. The reducer 10 applied to the driving device 4 will be described below with reference to FIGS. 2 to 4.

[0024] The reducer 10 shown in FIGS. 2 and 3 is an eccentric oscillating reducer, as described below. The reducer 10 is not limited to the illustrated example, and may be a planetary gear reducer. The illustrated reducer 10 includes a case 20, a carrier 30, a main bearing 15, and a seal member 60. The carrier 30 is at least partially disposed within the case 20. The carrier 30 is rotatable about a rotation axis RA relative to the case 20 via the main bearing 15. The illustrated main bearing 15 is disposed between the case 20 and the carrier 30 in a radial direction DR perpendicular to the rotation axis RA. The seal member 60 provides a seal between the case 20 and the carrier 30. The illustrated seal member 60 is at least partially disposed within the case 20.

[0025] The reducer 10 shown in FIGS. 2 and 3 includes a crankshaft 40 and an external gear 50. The crankshaft 40 is supported by the carrier 30 so as to be rotatable about a rotation axis RAC relative to the carrier 30. The external gear 50 is driven by the rotation of the crankshaft 40 relative to the carrier 30. The driven external gear 50 causes the carrier 30 to rotate about a rotation axis RA relative to the case 20. In the illustrated reducer 10, the rotation of the carrier 30 relative to the case 20 is output as rotational motion. Therefore, the illustrated carrier 30 serves as the output shaft of the reducer 10. It should be noted that the case 20 may serve as the output shaft of the reducer 10 instead of the carrier 30.

[0026] 2 and 3 includes a case body 21. A first hole 22 is formed in the case body 21, penetrating the case body 21 in the axial direction DA. The illustrated first hole 22 forms a space for at least partially accommodating the main bearing 15, the carrier 30, the crankshaft 40, the external gear 50, and the seal member 60.

[0027] 2 and 3, the case body 21 may be formed with a plurality of second holes 23 arranged in a circumferential direction DC. The circumferential direction DC is a circumferential direction centered on the rotation axis RA. Each second hole 23 penetrates the case body 21 in the axial direction DA. In the illustrated driving device 4, a bolt B1 for fixing the reducer 10 to another component of the driving device 4 can pass through the second hole 23 of the case 20. The other component of the driving device 4 may be a housing that accommodates a motor.

[0028] The case 20 shown in Figures 2 and 3 includes a plurality of internally toothed pins 24 held on the inner surface of the case body 21. Pin grooves arranged along the circumferential direction DC are formed on the inner surface of the case body 21. The pin grooves extend in an axial direction DA parallel to the rotation axis RA. The internally toothed pins 24 are housed in the pin grooves. The internally toothed pins 24 housed in the pin grooves are rotatable relative to the case body 21 around the rotation axis extending in the axial direction DA. The plurality of internally toothed pins 24 shown in Figure 3 form internal teeth 25 of the case 20.

[0029] 2 and 4 includes, on its inner circumferential surface, a contact surface 26 with which the main bearing 15 comes into contact. The illustrated contact surface 26 extends in the axial direction DA along the circumferential direction DC. The illustrated case 20 includes, as the contact surface 26, a first contact surface 261 with which the first main bearing 151 comes into contact, and a second contact surface 262 with which the second main bearing 152 comes into contact. The first main bearing 151 and the second main bearing 152 will be described later.

[0030] 2 and 3 is at least partially disposed within the first hole 22. The rotation axis RA of the carrier 30 is located within the first hole 22. The illustrated carrier 30 includes a portion having a diameter smaller than the diameter of the first hole 22, i.e., the inner diameter of the case body 21. The illustrated carrier 30 also includes a portion having a diameter larger than the diameter of the first hole 22.

[0031] 2 includes a carrier base portion 31 and a plate portion 32 adjacent to the carrier base portion 31 in the axial direction DA. The illustrated carrier base portion 31 and the plate portion 32 are restricted from moving relative to each other by a bolt B2. The illustrated rotation axis of the bolt B2 is parallel to the axial direction DA.

[0032] As shown in FIG. 4, the carrier 30 may be at least partially disposed within the case 20 with a gap G between the case 20 and the carrier 30. In FIG. 4, the gap G between the case 20 and the carrier 30 opens outward in the radial direction DR, i.e., in a direction away from the rotation axis RA in the radial direction DR. The gap G includes a first portion G1 and a second portion G2 connected to the first portion G1. The first portion G1 and the second portion G2 extend in directions non-parallel to each other. The illustrated first portion G1 extends in the radial direction DR. The illustrated second portion G2 extends in the axial direction DA. The gap G is located outward in the radial direction DR from a contact region 65 (described later) of the first ring 61.

[0033] The carrier base portion 31 shown in FIGS. 2 and 3 includes a disk-shaped base plate portion 311 and pillar portions 312 protruding from the base plate portion 311 in the axial direction DA. The illustrated base plate portion 311 and pillar portions 312 are integrally formed. As shown in FIG. 3, a plurality of pillar portions 312 protrude from the base plate portion 311. FIG. 3 shows three pillar portions 312 arranged at equal intervals in the circumferential direction DC. Each pillar portion 312 is formed with a screw hole SH2 that engages with a bolt B2. The screw hole SH2 shown in FIG. 2 opens in the axial direction DA toward the plate portion 32.

[0034] As shown in FIGS. 2 and 4, the carrier 30 may have a recess 30r for at least partially accommodating the seal member 60. The illustrated recess 30r is formed in a base plate portion 311 of the carrier base portion 31. The recess 30r opens in the axial direction DA toward the first hole 22 of the case 20. In the illustrated carrier base portion 31, the recess 30r is located outward in the radial direction DR from the pillar portions 312. The recess 30r extends in the circumferential direction DC. The illustrated base plate portion 311 is recessed in a portion where the recess 30r is formed, in a direction opposite to the direction in which the pillar portions 312 protrude in the axial direction DA. As shown in FIGS. 2 and 4, the recess 30r may include a portion that is at least partially disposed within the first hole 22 when the carrier 30 is at least partially disposed within the case 20.

[0035] The plate portion 32 shown in Fig. 2 has a through hole TH2 formed therein through which the bolt B2 can pass. The through hole TH2 overlaps with the screw hole SH2 in the axial direction DA. As shown in Fig. 2, the through hole TH2 may be enlarged in diameter to accommodate the head of the bolt B2.

[0036] 2 is formed with a central hole 34 that penetrates the carrier 30 in the axial direction DA. The illustrated central hole 34 penetrates the carrier base portion 31 and the plate portion 32. In the illustrated carrier 30, the rotation axis RA is located within the central hole 34.

[0037] 2 has a plurality of through holes 35 formed therein that penetrate the carrier 30 in the axial direction DA. The illustrated carrier 30 has three through holes 35 formed therein that are arranged at equal intervals in the circumferential direction DC. Each through hole 35 penetrates the carrier base portion 31 and the plate portion 32. The illustrated central hole 34 and through holes 35 are connected to each other at the end of the carrier 30 that is remote from the case 20 in the axial direction DA.

[0038] A first bearing 11 is disposed in the through hole 35 shown in Fig. 2. Two first bearings 11 spaced apart from each other in the axial direction DA are disposed in the illustrated through hole 35. By being held within the carrier 30 via the first bearings 11, the crankshaft 40 is rotatable about a rotation axis RAC relative to the carrier 30. The rotation axis RAC of the crankshaft 40 is parallel to the axial direction DA. As shown in Fig. 2, the first bearings 11 may be tapered roller bearings.

[0039] 2 and 4 includes a contact surface 36 in the recess 30r that comes into contact with a first elastic ring 63 (described later) of the seal member 60. The contact surface 36 extends in the axial direction DA along the circumferential direction DC. As shown in Fig. 4, the contact surface 36 may include a portion that is located more inward in the radial direction DR than the contact surface 26 between the case 20 and the main bearing 15. Unlike Fig. 4, the contact surface 36 may also include a portion that is located more outward in the radial direction DR than the contact surface 26.

[0040] The contact surface 36 may be inclined with respect to the axial direction DA, as shown in Fig. 4. In the contact surface 36 shown in Fig. 4, the distance of the inclined contact surface 36 from the rotation axis RA decreases as it moves away from the case 20 in the axial direction DA. In the illustrated contact surface 36, the portion farthest from the case 20 in the axial direction DA is located more inward in the radial direction DR than the contact surface 26 between the case 20 and the main bearing 15.

[0041] The carrier 30 shown in FIGS. 2 and 3 is rotatable about a rotation axis RA relative to the case 20 via main bearings 15. The illustrated reducer 10 includes two main bearings 15 spaced apart from each other in the axial direction DA. The illustrated reducer 10 includes a first main bearing 151 and a second main bearing 152 as the two main bearings 15. The first main bearing 151 and the second main bearing 152 are disposed in a first hole 22 of the case 20. The first main bearing 151 is disposed between the case 20 (case main body 21) and the carrier base portion 31 in the radial direction DR. The second main bearing 152 is disposed between the case 20 (case main body 21) and the plate portion 32 in the radial direction DR.

[0042] Each of the two main bearings 15 shown in FIG. 2 includes an outer ring 16, an inner ring 17, and a plurality of rolling elements 18 disposed between the outer ring 16 and the inner ring 17. The inner ring 17 is disposed inward of the outer ring 16 in the radial direction DR, i.e., closer to the rotation axis RA in the radial direction DR. The outer ring 16 and the inner ring 17 extend in the circumferential direction DC. The outer ring 16 is attached to a case 20. The inner ring 17 is attached to a carrier 30. The plurality of rolling elements 18 are disposed at intervals in the circumferential direction DC. The illustrated main bearing 15 is a rolling bearing. The illustrated rolling elements 18 are balls. Therefore, the illustrated main bearing 15 is a ball bearing. In the illustrated main bearing 15, the inner ring 17 and the rolling elements 18 are movable in the circumferential direction DC relative to the outer ring 16. The main bearing 15 may include a cage (not shown) for maintaining the intervals between adjacent rolling elements 18 in the circumferential direction DC.

[0043] In the first main bearing 151 and the second main bearing 152 shown in Fig. 2 and Fig. 4, the outer ring 16 is attached to the case 20. The outer ring 16 contacts the inner circumferential surface (contact surface 26) of the case main body 21 from the inside in the radial direction DR. The outer ring 16 attached to the case 20 is restricted from moving relative to the case 20. As shown in Fig. 4, the outer ring 16 includes a curved surface 16r facing inward in the radial direction DR. The illustrated outer ring 16 contacts the rolling elements 18 at the curved surface 16r.

[0044] 2 and 4, the inner ring 17 is attached to the carrier base portion 31 of the carrier 30. The inner ring 17 contacts the outer peripheral surface of the carrier base portion 31 from the outside in the radial direction DR. In the first main bearing 151, the inner ring 17 attached to the carrier base portion 31 is restricted from moving relative to the carrier base portion 31 of the carrier 30.

[0045] 2, the inner ring 17 is attached to the plate portion 32 of the carrier 30. The inner ring 17 contacts the outer peripheral surface of the plate portion 32 from the outside in the radial direction DR. In the second main bearing 152, the inner ring 17 attached to the plate portion 32 is restricted from moving relative to the plate portion 32 of the carrier 30.

[0046] 4, the inner ring 17 includes a curved surface 17r facing outward in the radial direction DR. The illustrated inner ring 17 is in contact with the rolling elements 18 at the curved surface 17r.

[0047] The crankshaft 40 shown in FIG. 2 includes two eccentric bodies 41 arranged side by side in the axial direction DA. Each eccentric body 41 has a cylindrical shape with an axial direction DAE parallel to the axial direction DA. FIG. 2 shows the two eccentric bodies 41 as a first eccentric body 411 and a second eccentric body 412. The central axis CA1 of the first eccentric body 411 and the central axis CA2 of the second eccentric body 412 are offset in a radial direction DRE perpendicular to the axial direction DAE from the rotational axis RAC of the crankshaft 40. The central axis CA1 of the first eccentric body 411 is offset in the radial direction DRE from the rotational axis RAC of the crankshaft 40 in a direction away from the rotational axis RA. The central axis CA2 of the second eccentric body 412 is offset in the radial direction DRE from the rotational axis RAC of the crankshaft 40 in a direction toward the rotational axis RA. The deviation of the central axis CA1 from the rotation axis RAC may be the same as the deviation of the central axis CA2 from the rotation axis RAC.

[0048] 2 includes an input gear 42 disposed at an end in the axial direction DA. The input gear 42 meshes with an input shaft (not shown) disposed in the central hole 34. The input shaft may rotate about a rotation axis parallel to the axial direction DA. By meshing the input shaft with the input gear 42, the rotation of the input shaft is transmitted to the crankshaft 40.

[0049] The two external gears 50 shown in FIGS. 2 and 3 are housed in the case 20. Each external gear 50 is located between the base plate portion 311 and the plate portion 32 in the axial direction DA. The external gears 50 are driven by the rotation of the crankshaft 40 relative to the carrier 30. The illustrated reducer 10 includes two external gears 50 arranged side by side in the axial direction DA. FIG. 2 shows a first external gear 501 and a second external gear 502 as the two external gears 50 arranged side by side in the axial direction DA. Of the two external gears 50, the first external gear 501 is located on the base plate portion 311 side in the axial direction DA. Of the two external gears 50, the second external gear 502 is located on the plate portion 32 side in the axial direction DA. FIG. 3 shows the first external gear 501 of the two external gears 50.

[0050] The external gear 50 shown in FIG. 2 has a central hole 51 located in the center. The external gear 50 has external teeth 55 arranged along the outer periphery centered on the central hole 51. The number of teeth of the external teeth 55 is smaller than the number of teeth of the internal teeth 25, i.e., the number of internal tooth pins 24. As an example, the number of teeth of the external teeth 55 is one less than the number of teeth of the internal teeth 25. The outer diameter of the illustrated external gear 50 is smaller than the inner diameter of the case 20 at the portion where the internal tooth pin 24 is arranged.

[0051] The external gear 50 shown in Figures 2 and 3 has a plurality of eccentric body insertion holes 52 formed therein and arranged at equal intervals in the circumferential direction around a central hole 51. Figure 3 shows three eccentric body insertion holes 52 arranged in the circumferential direction. A second bearing 12 is disposed in each of the eccentric body insertion holes 52. The crankshaft 40 is rotatably held relative to the external gear 50 via the second bearing 12. In particular, in the crankshaft 40 shown in Figures 2 and 3, the eccentric body 41 is rotatably held relative to the external gear 50 via the second bearing 12.

[0052] The external gear 50 shown in Figures 2 and 3 has a plurality of column insertion holes 53 formed therein and arranged at equal intervals in the circumferential direction around the central hole 51. Figure 3 shows three column insertion holes 53 arranged in the circumferential direction. In the external gear 50 shown in Figure 3, the eccentric body insertion holes 52 and the column insertion holes 53 are arranged alternately in the circumferential direction. In Figures 2 and 3, the column portions 312 of the carrier base portion 31 pass through each column insertion hole 53.

[0053] The external gear 50 shown in Figures 2 and 3 has external teeth 55 on its outer circumferential surface. The external gear 50 contacts the multiple internally toothed pins 24 of the case 20 from its outer circumferential surface, which includes the external teeth 55. The external gear 50, driven by the crankshaft 40, moves relative to the case 20 while contacting the internally toothed pins 24 at the external teeth 55. As will be described later, the central axis of the external gear 50 moving relative to the case 20 orbits the rotation axis RA. The movement of the external gear 50 relative to the case 20 is transmitted to the carrier 30, causing the carrier 30 to rotate about the rotation axis RA relative to the case 20.

[0054] The reducer 10 shown in FIGS. 2 to 4 includes oil for lubricating components that move relative to the case 20. In the illustrated reducer 10, the components that move relative to the case 20 include the carrier 30, the main bearing 15, the crankshaft 40, and the external gear 50. The reducer 10 is formed with a lubrication region 70 in which oil is stored. The illustrated lubrication region 70 includes the main bearing 15 and the external gear 50. The illustrated lubrication region 70 includes at least a portion of the carrier 30 and the crankshaft 40. The oil stored in the lubrication region 70 lubricates the carrier 30, the main bearing 15, the crankshaft 40, and the external gear 50. In other words, the oil suppresses wear and heat generation in these components due to their movement relative to the case 20. The lubrication region 70 shown in FIG. 4 includes a portion located within the first hole 22 of the case 20 and a portion located within the recess 30r of the carrier 30. Note that the oil is not shown in FIG. 2.

[0055] 2 and 4 seals the lubrication region 70. The illustrated seal member 60 seals between the case 20 and the carrier 30. The seal member 60 prevents oil from leaking out of the lubrication region 70. The seal member 60 prevents foreign matter such as dust, earth and sand, and sewage from entering the lubrication region 70 and contaminating the oil. The seal member 60 prevents poor lubrication in the reducer 10 due to contaminated oil.

[0056] The seal member 60 shown in FIGS. 2 and 4 includes a first ring 61, a second ring 62, and a first elastic ring 63. As shown in FIGS. 2 and 4, the seal member 60 may also include a second elastic ring 64. The first ring 61 contacts the second ring 62 at an annular contact area 65. The annular contact area 65 extends in the circumferential direction DC. In the illustrated seal member 60, the first ring 61 and the second elastic ring 64 are disposed in the first hole 22. In the illustrated seal member 60, the second ring 62 and the first elastic ring 63 are disposed in the recess 30r of the carrier 30.

[0057] 4, a floating seal 66 is formed by the second ring 62 and the first elastic ring 63. In the illustrated seal member 60, a mating ring 67 is formed by the first ring 61 and the second elastic ring 64.

[0058] The first ring 61 shown in FIGS. 2 and 4 is annular. The annular first ring 61 is attached to the case 20. The first ring 61 may be attached to the case 20 by a loose fit. The first ring 61 attached to the case 20 includes a portion that contacts the case 20. The illustrated first ring 61 contacts the inner circumferential surface of the case main body 21, i.e., the surface facing inward in the radial direction DR, from the inside in the radial direction DR. The first ring 61 has a certain thickness in the axial direction DA when attached to the case 20. The illustrated first ring 61 is located between the first main bearing 151 and the second ring 62 in the axial direction DA. The first ring 61 may be made of a metal such as chrome-molybdenum steel or high-chromium steel. In the illustrated first ring 61, both the first portion 611 and the second portion 612 are made of metal.

[0059] 2 and 4 includes a portion located in the same region as the main bearing 15 in the radial direction DR. Specifically, the first ring 61 includes a portion located in the same region as each of the first main bearing 151 and the second main bearing 152 in the radial direction DR. Note that the "portion located in the same region as the main bearing 15 in the radial direction DR" of a certain component of the seal member 60 refers to a portion located between the portion closest to the rotation axis RA of the main bearing 15 and the portion farthest from the rotation axis RA of the main bearing 15 in the radial direction DR.

[0060] 4 includes a first surface 61a and a second surface 61b spaced apart from each other in the axial direction DA. The first surface 61a faces the axial direction DA. The first ring 61 contacts the second ring 62 at the first surface 61a. The first ring 61 faces the first main bearing 151 in the axial direction DA at the second surface 61b.

[0061] The first ring 61 shown in FIG. 4 includes a first portion 611 and a second portion 612 connected to the first portion 611 from the second ring 62 side in the axial direction DA. In the illustrated first ring 61, the first portion 611 and the second portion 612 are connected seamlessly. In the illustrated first ring 61, the first surface 61a is formed by the second portion 612. The second surface 61b includes a portion formed by the first portion 611 and a portion formed by the second portion 612. The illustrated first portion 611 includes a portion located in the same region as the first main bearing 151 in the axial direction DA. Specifically, the first portion 611 is located in the same region as the inner ring 17 of the first main bearing 151 in the axial direction DA. In other words, the first portion 611 faces the inner ring 17 in the radial direction DR.

[0062] 4, the length of the second portion 612 of the first ring 61 in the radial direction DR is greater than the length of the first portion 611 of the first ring 61 in the radial direction DR. The illustrated second portion 612 includes a portion located more inward in the radial direction DR than the first portion 611, i.e., closer to the rotation axis RA in the radial direction DR. The illustrated first ring 61 is in contact with the second ring 62 at a portion of the second portion 612 located more inward in the radial direction DR than the first portion 611.

[0063] 4, the first ring 61 may be formed with a groove 61g for accommodating the second elastic ring 64. The illustrated groove 61g is formed on the outer circumferential surface of the first ring 61, i.e., the surface facing outward in the radial direction DR. The outer circumferential surface of the first ring 61 is recessed inward in the radial direction DR at the groove 61g. The recess amount of the outer circumferential surface at the groove 61g may be smaller than the wire diameter of the second elastic ring 64.

[0064] 4 is connected to the lubrication region 70 at the second surface 61b and the inner circumferential surface. In other words, the first ring 61 can come into contact with the oil stored in the lubrication region 70 at the second surface 61b and the inner circumferential surface. The inner circumferential surface of the first ring 61 is the surface facing inward in the radial direction DR of the first ring 61.

[0065] 2 and 4, an annular contact area 65 is formed by the first surface 61a. The contact area 65 may also be referred to as a contact surface. The illustrated contact area 65 is located in the same region in the radial direction DR as the first main bearing 151 and the second main bearing 152. The contact area 65 shown in FIG. 4 is located in the same region in the radial direction DR as the rolling elements 18 of the first main bearing 151.

[0066] 4 includes a first surface 62a and a second surface 62b spaced apart from each other in the axial direction DA. The first surface 62a and the second surface 62b face in the axial direction DA. The second ring 62 contacts the first ring 61 at the second surface 62b. The second ring 62 may be made of a metal such as chrome-molybdenum steel.

[0067] 4 has a third surface 62c connecting the first surface 62a and the second surface 62b. When the second ring 62 is disposed in the recess 30r, the third surface 62c extends in the axial direction DA along the circumferential direction DC. The illustrated third surface 62c is spaced apart in the radial direction DR from the wall of the recess 30r.

[0068] The second ring 62 shown in FIGS. 2 and 4 includes a sloped surface 62i that is inclined with respect to the axial direction DA. The sloped surface 62i is located on the outer circumferential surface of the second ring 62. The length of the second ring 62, including the sloped surface 62i, in the radial direction DR increases as it approaches the case 20 (first hole 22) in the axial direction DA. As shown in FIG. 4, ends 62ia and 62ib of the sloped surface 62i in the axial direction DA may protrude outward in the radial direction DR. Of the illustrated ends 62ia and 62ib, the first end 62ia is located closer to the first ring 61 in the axial direction DA than the second end 62ib.

[0069] 2 and 4 is located in the same region as the first main bearing 151 and the second main bearing 152 in the radial direction DR. The illustrated second ring 62 is located in the same region as the rolling elements 18 of the main bearing 15 in the radial direction DR. The illustrated second ring 62 does not include a portion located outside the main bearing 15 in the radial direction DR.

[0070] 4 is connected to the lubricating region 70 at the first surface 62a, the second surface 62b, the third surface 62c, and a portion of the inclined surface portion 62i. The inclined surface portion 62i is connected to the lubricating region 70 in a region including the second end portion 62ib.

[0071] The first elastic ring 63 shown in Figures 2 and 4 is annular. The annular first elastic ring 63 extends in the circumferential direction DC. The illustrated first elastic ring 63 is disposed in the recess 30r of the carrier 30. The first elastic ring 63 contacts the carrier base portion 31 (base plate portion 311) of the carrier 30 from the inside in the radial direction DR. The first elastic ring 63 contacts the second ring 62 from the outside in the radial direction DR.

[0072] When the seal member 60 seals between the case 20 and the carrier 30, the first elastic ring 63 is compressed between the carrier 30 and the second ring 62, as shown in Fig. 4. The compressed first elastic ring 63 presses the second ring 62 toward the first ring 61 in the axial direction DA by contacting the second ring 62 from the inclined surface portion 62i.

[0073] 4 is located between both end portions 62ia, 62ib of the inclined surface portion 62i in the axial direction DA. In the illustrated seal member 60, the first elastic ring 63 is disposed between the protruding both end portions 62ia, 62ib, thereby restricting movement of the first elastic ring 63 in the axial direction DA relative to the second ring 62.

[0074] The first elastic ring 63 may include an elastically deformable material. For example, the first elastic ring 63 may include rubber. The first elastic ring 63 may be simply referred to as an "elastic ring."

[0075] The second elastic ring 64 shown in FIGS. 2 and 4 is disposed in a groove 61g formed on the outer peripheral surface of the first ring 61. The second elastic ring 64 disposed in the groove 61g is restricted from moving in the axial direction DA and the radial direction DR relative to the first ring 61. The second elastic ring 64 is disposed between the first ring 61 and the case 20 (case main body 21) in the radial direction DR. The second elastic ring 64 may seal the gap between the case 20 and the first ring 61 in the radial direction DR. The second elastic ring 64 may prevent foreign matter such as dust from entering the first hole 22 from between the first ring 61 and the case 20. The second elastic ring 64 may include an elastically deformable material. For example, the second elastic ring 64 may include rubber.

[0076] The operation of the reducer 10 shown in FIGS. 2 and 3 will be described.

[0077] Torque from an input shaft (not shown) is transmitted to an input gear 42 of the crankshaft 40. The torque transmitted from the input gear 42 causes the crankshaft 40 to rotate about a rotation axis RAC relative to the case 20 and the carrier 30. In the crankshaft 40 rotating about the rotation axis RAC, the eccentric body 41 rotates eccentrically relative to the case 20 and the carrier 30. Of the two eccentric bodies 41 shown in FIG. 2 , the first eccentric body 411 rotates with its central axis CA1 offset in the radial direction DRE from the rotation axis RAC. The second eccentric body 412 rotates with its central axis CA2 offset in the radial direction DRE from the rotation axis RAC.

[0078] The external gear 50 is driven by the eccentric rotation of the eccentric body 41. The two external gears 50 shown in FIG. 2 move in the radial direction DR relative to the case 20 while contacting the internal pins 24 of the case 20 at their outer circumferential surfaces. Each internal pin 24 rotates relative to the case body 21 about a rotation axis parallel to the axial direction DA by contact with the external gear 50. As described above, the number of teeth of the illustrated external teeth 55 is one less than the number of internal pins 24. As a result, in the external gear 50 moving relative to the case 20, the central axis of the external gear 50 moves in the circumferential direction DC around the rotation axis RA while being shifted in the radial direction DR from the rotation axis RA. In other words, the external gear 50 moving relative to the case 20 revolves around the rotation axis RA. The revolution period of the external gear 50, that is, the time it takes for the central axis of the external gear 50 to complete one revolution along an orbit extending in the circumferential direction DC, is greater than the rotation period of the crankshaft 40 and the eccentric body 41.

[0079] The orbital motion of the external gear 50 is transmitted to the carrier 30 that supports the external gear 50. As a result, the carrier 30 rotates about the rotation axis RA relative to the case 20. Because the orbital period of the external gear 50 is greater than the rotation period of the crankshaft 40 and the eccentric body 41, the carrier 30 rotates relative to the case 20 at a rotation speed that is slower than the rotation speed of the input shaft. Therefore, in the illustrated reducer 10, the rotational motion of the carrier 30 relative to the case 20 is output as rotational motion that is slower than the rotational motion input from the input shaft.

[0080] The function of the seal member 60 in the above-described reducer 10 will be described.

[0081] In the seal member 60 shown in FIGS. 2 and 4 , the first elastic ring 63 is connected to the lubrication region 70. The first elastic ring 63 is disposed in a compressed state between the second ring 62 and the carrier 30 in the radial direction DR. Compression of the first elastic ring 63 between the second ring 62 and the carrier 30 suppresses the outflow of oil from between the first elastic ring 63 and the second ring 62 and between the first elastic ring 63 and the carrier 30. Similarly, compression of the first elastic ring 63 between the second ring 62 and the carrier 30 suppresses the inflow of foreign matter from between the first elastic ring 63 and the second ring 62 and between the first elastic ring 63 and the carrier 30.

[0082] 2 and 4, the second ring 62 is connected to the lubrication region 70. The second ring 62 is pressed in the axial direction DA toward the first ring 61 by the first elastic ring 63, which is compressed between the carrier 30 and the second ring 62. The second ring 62 contacts an annular contact region 65 of the first ring 61. The second ring 62 is pressed toward the first ring 61 in the axial direction DA and contacts the first ring 61, thereby suppressing the outflow of oil and the inflow of foreign matter from the contact region 65.

[0083] 2 and 4, the first ring 61 is connected to the lubrication region 70. The first ring 61 is attached to the case 20. The illustrated first ring 61 contacts the outer peripheral surface of the case 20 (case main body 21) from the inside in the radial direction DR. By attaching the first ring 61 to the case 20, the outflow of oil from between the first ring 61 and the case 20 and the inflow of foreign matter from between the first ring 61 and the case 20 are suppressed.

[0084] 2 and 4, a second elastic ring 64 is disposed in the groove 61g of the first ring 61. The second elastic ring 64 is disposed in a compressed state between the first ring 61 and the case 20 in the radial direction DR. Compressing the second elastic ring 64 between the first ring 61 and the case 20 more effectively prevents oil from leaking out from between the second elastic ring 64 and the first ring 61 and between the first ring 61 and the case 20. Similarly, compressing the second elastic ring 64 between the first ring 61 and the case 20 more effectively prevents foreign matter from leaking in from between the second elastic ring 64 and the first ring 61 and between the first ring 61 and the case 20.

[0085] When the carrier 30 rotates about the rotation axis RA relative to the case 20, the second ring 62 rotates together with the first elastic ring 63 and the carrier 30 relative to the case 20 while maintaining contact with the first ring 61. In other words, in the illustrated seal member 60, the floating seal 66 rotates together with the carrier 30 relative to the case 20 while contacting the mating ring 67 in an annular region. Therefore, the seal member 60 can suppress the outflow of oil from the annular contact region 65 of the first ring 61 and the inflow of foreign matter from the contact region 65, even when the carrier 30 is rotating relative to the case 20.

[0086] When the carrier 30 rotates about the rotation axis RA relative to the case 20, the first elastic ring 63 rotates together with the carrier 30 and the second ring 62 while remaining compressed between the second ring 62 and the carrier 30. The first elastic ring 63 prevents oil from leaking out from between the first elastic ring 63 and the second ring 62 and between the first elastic ring 63 and the carrier 30, even when the carrier 30 is rotating relative to the case 20. The first elastic ring 63 can prevent foreign matter from entering between the first elastic ring 63 and the second ring 62 and between the first elastic ring 63 and the carrier 30, even when the carrier 30 is rotating relative to the case 20.

[0087] When the carrier 30 rotates about the rotation axis RA relative to the case 20, the first ring 61 and the second elastic ring 64 are restricted from moving relative to the case 20. In other words, in the illustrated seal member 60, the mating ring 67 is restricted from moving relative to the case 20.

[0088] In reducers used outdoors, sealing members including floating seals are used to prevent foreign matter such as dust, soil, and sewage from entering the lubrication area. Sealing members including floating seals have high resistance to foreign matter, and can effectively prevent foreign matter from entering the lubrication area and oil from leaking from the lubrication area in reducers used outdoors. However, installing the sealing member away from components that move relative to the case, such as the carrier and bearings, increases the lubrication area, i.e., the area where oil is stored, in the reducer. This expansion of the lubrication area increases the amount of oil stored in the reducer. This increase in stored oil can increase the amount of oil used in the reducer and the weight of the reducer.

[0089] 2 and 4, the seal member 60 is located in at least a partial area of the main bearing 15 in a radial direction DR perpendicular to the rotation axis RA of the carrier 30 relative to the case 20. In particular, in the illustrated seal member 60, the first ring 61, the second ring 62, and the first elastic ring 63 are each located in at least a partial area of the main bearing 15 in the radial direction DR. Furthermore, the second ring 62 and the first elastic ring 63 shown in FIGS. 2 and 4 do not include portions located outward of the main bearing 15 in the radial direction DR.

[0090] 2 and 4, the seal member 60 is disposed close to the main bearing 15 in the radial direction DR. By disposing the seal member 60 and the main bearing 15 close to each other in the radial direction DR, the illustrated reducer 10 can suppress expansion of the lubrication area 70 in the radial direction DR between the case 20 and the carrier 30. By suppressing expansion of the lubrication area 70, the amount of oil stored in the reducer 10 can be reduced, and the weight of the reducer 10 can be reduced.

[0091] 4, the contact area 65 of the first ring 61 is located within the first hole 22 formed in the case 20. That is, the contact area 65 is located within the case 20. By disposing the contact area 65 within the case 20, it is possible to suppress the expansion of the lubrication area 70 outside the case 20 in the axial direction DA. Therefore, with the illustrated seal member 60, it is possible to suppress the expansion of the lubrication area 70 in the axial direction DA.

[0092] In the seal member 60 shown in FIGS. 2 and 4, the first ring 61 is disposed between the second ring 62 and the first main bearing 151 in the axial direction DA. The first ring 61 includes a first portion 611 and a second portion 612 connected to the first portion 611. The first portion 611 is located in the same region as the main bearing 15 in the axial direction DA. That is, the first ring 61 includes a portion located in the same region as the main bearing 15 in the axial direction DA. By disposing the first ring 61 in this manner, the protrusion length of the seal member 60 from the main bearing 15 in the axial direction DA can be reduced. As a result, in the illustrated reducer 10, it is possible to suppress expansion of the lubrication region 70 in the axial direction DA between the case 20 and the carrier 30.

[0093] The first ring 61 shown in FIG. 4 has a thickness that presses the second ring 62 toward the first elastic ring 63 in the axial direction DA at the contact area 65, which is the sum of the thicknesses of the first portion 611 and the second portion 612. In the illustrated seal member 60, a force that presses the first ring 61 toward the case 20 from the second ring 62 and a force that presses the second ring 62 toward the first elastic ring 63 act on the contact area 65. That is, forces that act in opposite directions in the axial direction DA act on the contact area 65. The illustrated seal member 60 can stably seal between the first ring 61 and the second ring 62 because the first ring 61 has a sufficient thickness. Therefore, the inflow of foreign matter and the outflow of oil at the contact area 65 can be suppressed.

[0094] 2 and 4, the second portion 612 of the first ring 61 of the seal member 60 includes a portion located more inward in the radial direction DR than the first portion 611. The first ring 61 contacts the second ring 62 at the second portion 612. According to the illustrated seal member 60, the second ring 62, which contacts the first ring 61, can be positioned more inward in the radial direction DR than the first ring 61. This allows the portion of the lubrication region 70 that connects to the second ring 62 to be positioned more inward in the radial direction DR, as shown in FIG. 4. Therefore, expansion of the lubrication region 70 in the radial direction DR can be suppressed at the portion that connects to the second ring 62.

[0095] The carrier 30 shown in Fig. 4 is at least partially disposed within the case 20 with a gap G between the carrier 30 and the case 20. The gap G is located outside the contact area 65 in the radial direction DR. The gap G includes a first portion G1 extending in the radial direction DR and a second portion G2 extending in the axial direction DA. As shown in Fig. 4, the gap G includes portions that extend in directions that are not parallel to each other, which makes it possible to prevent foreign matter from outside the reducer 10 from reaching the contact area 65 of the first ring 61.

[0096] In the embodiment described above, the reducer 10 includes a case 20, a carrier 30, a main bearing 15, and a seal member 60. The carrier 30 is at least partially disposed within the case 20. The main bearing 15 is disposed between the case 20 and the carrier 30. The seal member 60 includes a first ring 61, a second ring 62, and a first elastic ring 63. The first ring 61 is annular and attached to one of the case 20 and the carrier 30. The second ring 62 contacts an annular contact area 65 of the first ring 61. The first elastic ring 63 is compressed between the other of the case 20 and the carrier 30 and the second ring 62. The seal member 60 is located at least partially in the same region as the main bearing 15 in a radial direction DR perpendicular to a rotation axis RA of the carrier 30 relative to the case 20.

[0097] According to this embodiment, it is possible to prevent the lubrication region 70 of the reducer 10, which is located between the case 20 and the carrier 30, from expanding outward in the radial direction DR. By preventing the expansion of the lubrication region 70, it is possible to reduce the amount of oil stored in the lubrication region 70 in the reducer 10 that includes the seal member 60. As a result of reducing the amount of oil stored in the lubrication region 70, it is possible to reduce the cost of manufacturing the reducer 10 that includes the seal member 60 and the weight of such a reducer 10.

[0098] Although one embodiment has been described with reference to specific examples, the above-described specific examples do not limit the present invention. The above-described embodiment can be implemented with various other specific examples, and various omissions, substitutions, changes, additions, etc. can be made without departing from the spirit of the present invention.

[0099] In the above-described seal member 60, the first ring 61 is attached to the case 20. The first ring 61 is disposed between the main bearing 15 (first main bearing 151) and the second ring 62 in the axial direction DA. The first elastic ring 63 is compressed between the carrier 30 and the second ring 62. However, this is not limiting, and the first ring 61 may be attached to the carrier 30 as shown in FIG. 5. As shown in FIG. 5, the first elastic ring 63 may be compressed between the case 20 and the second ring 62. The illustrated first ring 61 is attached to the base plate portion 311 of the carrier base portion 31. The first ring 61 attached to the base plate portion 311 is restricted from moving relative to the carrier base portion 31. The seal member 60 may include a second elastic ring 64 compressed between the first ring 61 and the carrier 30 (carrier base portion 31) as shown in FIG. 5.

[0100] The first ring 61 shown in FIG. 4 includes a first portion 611 and a second portion 612 connected to the first portion 611 in the axial direction DA. The thickness of the first portion 611, i.e., its length in the axial direction DA, is smaller than the thickness of the second portion 612. However, this is not limiting, and the second portion 612 may have a thickness smaller than that of the first portion 611, as shown in FIG. 6. Furthermore, the length of the first ring 61 in the radial direction DR may be smaller at a connection portion 611c where the first portion 611 connects to the second portion 612 than at a portion other than the connection portion 611c of the first portion 611, as shown in FIG.

[0101] In the first ring 61 shown in Fig. 4, the first portion 611 and the second portion 612 are connected seamlessly. However, this is not limiting, and as shown in Fig. 7, the first ring 61 may include an intermediate portion 613 disposed between the first portion 611 and the second portion 612. The first portion 611 may be connected to the second portion 612 via the intermediate portion 613.

[0102] 6 and 7, the first ring 61 may have a shape that is deformable by a force applied to the first ring 61 from the second ring 62. In the illustrated first ring 61, the length of the first portion 611 in the radial direction DR is shorter at a connection portion 611c of the first portion 611 than at a portion other than the connection portion 611c of the first portion 611. The illustrated first ring 61 is in contact with the second ring 62 at the second portion 612.

[0103] When a force is applied to the first ring 61 shown in FIGS. 6 and 7 from the second ring 62 toward the main bearing 15 in the axial direction DA, the first ring 61 bends at the second portion 612, with the connection portion 611c as a fulcrum. The illustrated second portion 612 bends so that the end portion away from the portion that contacts the case 20 in the radial direction DR approaches the axial direction DA. When the first ring 61 bends at the second portion 612, the seal member 60 maintains a state in which the first surface 61a of the first ring 61 and the second surface 62b of the second ring 62 are in contact. With the illustrated seal member 60, when the first ring 61 contacts the second ring 62 at the contact region 65, the lubrication region 70 is sealed and the force applied to the first ring 61 from the second ring 62 is reduced. The reduced force applied to the first ring 61 improves the durability of the first ring 61.

[0104] In the first ring shown in FIG. 7, the intermediate portion 613 is made of a material having a smaller Young's modulus than the material of the first portion 611 and the material of the second portion 612. When the illustrated first ring 61 is pressed in the axial direction DA by the second ring 62 toward the main bearing 15, the intermediate portion 613 is compressed and deformed. By the deformation of the intermediate portion 613, in the first ring 61 shown in FIG. 7, the amount of deformation in the first portion 611 and the second portion 612 that form the second surface 61b can be suppressed. This can improve the durability of the first ring 61.

[0105] Among the embodiments disclosed in this specification, those that are comprised of multiple objects may be integrated, and conversely, those that are comprised of a single object may be separated into multiple objects. Regardless of whether they are integrated, it is sufficient that they are configured to achieve the object of the invention. [Explanation of symbols]

[0106] 1: industrial machine, 10: reducer, 15: main bearing, 20: case, 30: carrier, 60: sealing member, 61: first ring, 611: first part, 612: second part, 613: intermediate part, 62: second ring, 63: first elastic ring, 64: second elastic ring, 65: contact area, 66: floating seal, 67: mating ring, 70: lubrication area, DA: axial direction, DC: circumferential direction, DR: radial direction

Claims

1. Case and a carrier at least partially disposed within the case; a main bearing disposed between the case and the carrier; a first annular ring attached to one of the case and the carrier, a second ring in contact with an annular region of the first ring, and an elastic ring compressed between the other of the case and the carrier and the second ring, and a sealing member located at least partially in the same region as the main bearing in a radial direction perpendicular to a rotation axis of the carrier relative to the case.

2. The reducer according to claim 1 , wherein the first ring has a thickness in the annular region that presses the second ring toward the elastic ring.

3. The reducer according to claim 1 , wherein the annular region is located within the case.

4. the first ring is disposed between the second ring and the main bearing in an axial direction parallel to the rotation axis, The reducer according to claim 1 , wherein the first ring includes a portion that is located in at least a partial area in the axial direction with the main bearing.

5. the first ring includes a first portion and a second portion connected to the first portion in an axial direction parallel to the rotation axis, the first portion is located in the same region as the main bearing in the axial direction, the second portion includes a portion located radially inward of the first portion, The reducer according to claim 1 , wherein the first ring contacts the second ring at the second portion.

6. The reducer according to claim 5 , wherein the length of the first portion in the radial direction decreases at a connection portion with the second portion.

7. 7. The reducer according to claim 6, wherein the first ring includes an intermediate portion disposed between the first portion and the second portion and made of a material having a smaller Young's modulus than the material of the first portion and the material of the second portion.

8. the carrier is at least partially disposed within the case with a gap between the carrier and the case, on a radially outer side of the annular region; The reducer according to claim 1 , wherein the gap includes a portion extending in the radial direction and a portion extending in an axial direction parallel to the rotation axis.

9. A drive unit including a reducer is provided, The reducer includes a case, a carrier at least partially disposed within the case, a main bearing disposed between the case and the carrier, and a seal member that seals between the case and the carrier, the seal member includes an annular first ring attached to one of the case and the carrier, a second ring in contact with an annular region of the first ring, and an elastic ring compressed between the other of the case and the carrier and the second ring, The seal member is positioned in at least a partial area with the main bearing in a radial direction perpendicular to a rotation axis of the carrier relative to the case.

Images