JP2016151295A - Seal structure and gear device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit a coolant or the like from immersing into a device at low cost.SOLUTION: The seal structure includes: a casing 17; a carrier Ca rotating relatively with the casing; and an oil seal 50 disposed between the casing and the carrier. The seal structure also includes: an umbrella member 60 for covering a space P1 outside the oil seal; and an O-ring 70 disposed in an outer periphery of the carrier on an outer side relative to the oil seal.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a seal structure and a gear device.

  Patent Document 1 discloses a rotating device that includes a casing and a carrier that rotates relative to the casing. A first oil seal is disposed between the casing and the carrier.

  In this rotating device, a mating member (a member of another device) is further extended outward in the radial direction of the casing. A second oil seal is disposed between the mating member and the casing. The second oil seal blocks the coolant from entering the rotating device from the outside of the rotating device and reduces damage to the first oil seal.

JP 2001-254787 A (FIG. 4)

  Since the structure disclosed in Patent Document 1 requires two oil seals, there is a problem of high cost.

  The present invention has been made to solve the above-described conventional problems, and it is an object of the present invention to provide a seal structure and a gear device that can suppress the entry of coolant or the like into the device at low cost. It is said.

  The present invention provides a sealing structure comprising a casing, a carrier that rotates relative to the casing, and an oil seal disposed between the casing and the carrier, and an umbrella member that covers a space outside the oil seal. And the O-ring disposed on the outer periphery of the carrier outside the oil seal, the problem is solved.

Further, the present invention provides a seal structure comprising a casing, a carrier that rotates relative to the casing, and an oil seal disposed between the casing and the carrier.
What solved the said subject by making it the structure provided with the umbrella member which covers the space outside the said oil seal, and the ring-shaped groove | channel formed in the outer periphery of the said carrier outside the said oil seal It is.

  The present invention also provides an external gear, an internal gear meshing with the external gear, a casing provided with the internal gear, a carrier that rotates relative to the casing, and between the casing and the carrier. And an oil seal disposed on the outer periphery of the carrier on the side opposite to the external gear than the oil seal, and an umbrella member that covers the space on the side opposite to the external gear of the oil seal. The above-described problems are solved by providing a configuration including the O-ring.

  The present invention also provides an external gear, an internal gear that meshes with the external gear, a casing provided with the internal gear, a carrier that rotates relative to the casing, and the casing and the carrier. A bevel member that covers the space on the side opposite to the external gear of the oil seal, and is formed on the outer periphery of the carrier on the side opposite to the external gear than the oil seal. The above-described problems are solved by providing a ring-shaped groove.

  In the present invention, most of the coolant that falls on the oil seal is first removed by the umbrella member. Then, coolant or the like dripped from the umbrella member (or coolant that has passed through the umbrella member) is guided to the lower side of the carrier by an O-ring or a groove disposed on the outer periphery of the carrier. Thereby, it can suppress that coolant etc. penetrate | invade in an apparatus.

  According to the seal structure and the gear device according to the present invention, it is possible to suppress the coolant or the like from entering the device at low cost.

1 is an overall cross-sectional view showing the configuration of an eccentric oscillation type reduction gear to which a seal structure according to an example of an embodiment of the present invention is applied. 1 is an enlarged view of the main part of FIG. The principal part enlarged view equivalent to FIG. 2 which shows an example of other embodiment of this invention The principal part enlarged view equivalent to FIG. 2 which shows an example of other embodiment of this invention The principal part enlarged view equivalent to FIG. 2 which shows an example of other embodiment of this invention The principal part enlarged view equivalent to FIG. 2 which shows an example of other embodiment of this invention

  Hereinafter, a seal structure according to an example of an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an overall cross-sectional view showing a configuration of an eccentric oscillating speed reduction device to which a seal structure according to an example of an embodiment of the present invention is applied, and FIG. 2 is an enlarged view of a main part of FIG.

  First, the outline of the reduction gear will be described.

  The speed reducer 10 is an eccentric oscillating speed reducer called a sort type. The reduction gear 10 is used by being incorporated in a machine tool that is cooled by coolant. In this embodiment, the speed reducer 10 is assembled to a machine tool with the axial direction oriented in the horizontal direction.

  The reduction gear device 10 includes an external gear 12 and a crankshaft 14 that swings the external gear 12. The external gear 12 is in mesh with the internal gear 16 while swinging. The reduction gear 10 takes out the relative rotation of the external gear 12 and the internal gear 16 as an output.

  The reduction gear device 10 includes a plurality of crankshaft gears 18 for driving the crankshaft 14 (three in this example: only one is shown in FIG. 1). Each crankshaft gear 18 meshes simultaneously with the input gear 13 provided on the input shaft 11. Each crankshaft gear 18 includes an inner spline 18A for connecting to the crankshaft 14 on the inner periphery.

  The crankshaft 14 includes an outer spline 14B connected to the inner spline 18A of the crankshaft gear 18 on the outer periphery of the end of the shaft body 14A. A plurality of crankshafts 14 are arranged at positions offset from the axis C16 of the internal gear 16. In this example, three crankshafts 14 (only one is shown in FIG. 1) are provided, and are arranged on the same circumference at intervals of 120 ° in the circumferential direction.

  Each crankshaft 14 includes two eccentric bodies 14 </ b> C for swinging and rotating the external gear 12. Each eccentric body 14 </ b> C is formed of a cylinder having an axis C <b> 14 </ b> C that is eccentric with respect to the axis C <b> 14 of the crankshaft 14 by an eccentric amount e. The eccentric phase difference between the two eccentric bodies 14C is 180 ° in this example (eccentric in a direction away from each other). The three crankshafts 14 have the same configuration, and the eccentric phases of the eccentric bodies 14C at the same position in the axial direction of each crankshaft 14 are the same.

  An eccentric body bearing 20 is disposed between the external gear 12 and the eccentric body 14C. The external gear 12 is in mesh with the internal gear 16. The internal gear 16 has an internal gear main body 16A and an internal tooth pin 16C. The internal gear main body 16A is integrated with the casing 17 of the speed reducer 10 and has a plurality of pin grooves 16B in the circumferential direction. The internal tooth pin 16C is configured by a cylindrical member. The internal tooth pin 16 </ b> C is rotatably incorporated in the pin groove 16 </ b> B of the internal gear main body 16 </ b> A and constitutes an internal tooth of the internal gear 16. The number of teeth of the internal gear 16 (the number of the internal tooth pins 16C) is slightly larger (only 1 in this example) than the number of teeth of the external gear 12.

  A first carrier body 31 and a second carrier body 32 are disposed on both sides of the external gear 12 in the axial direction. A carrier pin 33 protrudes integrally from the first carrier body 31. The first carrier body 31 and the second carrier body 32 are connected by a connecting bolt 34 via a carrier pin 33. The integrated first carrier body 31, carrier pin 33, and second carrier body 32 constitute a carrier Ca.

  The external gear 12 has a carrier pin hole 12A at a position offset from the axis C12 of the external gear 12. The carrier pin 33 passes through the carrier pin hole 12A in a non-contact manner (with a gap). The external gear 12 has a through hole 12C in the radial center.

  The crankshaft 14 is supported by the first carrier body 31 and the second carrier body 32 via a tapered roller bearing 36. The carrier Ca (first and second carrier bodies 31 and 32 thereof) is supported by the casing 17 via a pair of angular roller bearings 35.

  In the present embodiment, the casing 17 is connected with a first member (not shown) 38 of the machine tool via a casing bolt 19. A second member (not shown) 42 of the machine tool is connected to the first carrier body 31 via a connecting bolt 40.

  In the reduction gear 10, when the input gear 13 of the input shaft 11 rotates, the three crankshaft gears 18 meshed simultaneously with the input gear 13 rotate in the same direction at the same rotational speed. When the crankshaft gears 18 are rotated, the three crankshafts 14 that are splined to the respective crankshaft gears 18 are rotated in the same direction at the same rotational speed.

  Thereby, the external gear 12 rotates eccentrically via the eccentric body 14C formed in each crankshaft 14 and the eccentric body bearing 20 incorporated in the outer periphery of the eccentric body 14C. Each time the crankshaft 14 rotates once, the external gear 12 and the internal gear 16 rotate relative to each other by an amount corresponding to the difference in the number of teeth (1 in this example) (when viewed from one gear, the other Of the gear rotates). This rotation is transmitted to the first and second carrier bodies 31 and 32 of the carrier Ca as revolutions around the axis C16 of the internal gear 16 of each crankshaft 14. Therefore, the second member 42 of the machine tool connected to the first carrier body 31 can be rotated relative to the first member 38 of the machine tool connected to the casing 17.

  Here, the seal structure of the reduction gear 10 will be described in detail.

  Referring also to FIG. 2, an oil seal 50 is disposed between the casing 17 and the first carrier body 31 of the carrier Ca.

  An oil seal (not shown) is also arranged on the first member 38 side, and a sealed space sealed by a member including the casing 17 and the carrier Ca is formed in the speed reduction device 10.

  The oil seal 50 is entirely formed of an elastic member, and a cross section passing through the axis C16 of the internal gear 16 is formed in a ring shape having a U-shape. The oil seal 50 includes a fitting portion 51, a lip portion 52, and a seal wall portion 53 that connects the fitting portion 51 and the lip portion 52.

  The fitting portion 51 of the oil seal 50 extends from the outer end portion of the seal wall portion 53 in parallel with the shaft, and is fixed to the fitting surface 17E on the inner periphery of the casing 17 by an interference fit. The lip portion 52 of the oil seal 50 includes a main lip portion 52A and a sub lip portion 52B. The main lip portion 52A extends from the inner end portion of the seal wall portion 53 to the inside of the reduction gear. The main lip portion 52A is pressed against the seal surface 31A1 formed on the outer periphery 31A of the first carrier body 31 of the carrier Ca by the urging force of the spring 54. The sub lip portion 52B is formed to protrude from the end portion of the main lip portion 52A on the seal wall portion 53 side to the first carrier body 31 side. The sub lip portion 52B is pressed against the seal surface 31A1 by elasticity.

  The oil seal 50 is incorporated in such a manner that the U-shaped open side is directed to the inner side of the speed reduction device 10 and the seal wall portion 53 is positioned on the outer side of the speed reduction device 10. That is, the main lip portion 52 </ b> A of the oil seal 50 mainly functions so that the lubricant inside the speed reduction device 10 does not leak out of the speed reduction device 10. The auxiliary lip portion 52B of the oil seal 50 mainly functions so that coolant, dust, and the like do not enter the seal surface 31A1 from the outside of the reduction gear 10.

  In other words, the oil seal 50 does not necessarily have a sufficient sealing function with respect to the penetration of the coolant into the reduction gear. Further, the durability of the oil seal 50 tends to decrease when the coolant collides violently with the oil seal 50. Therefore, in this embodiment, the following seal structure is adopted.

  This seal structure includes an umbrella member 60 that covers a space P1 outside the oil seal 50, and an O-ring 70 that is disposed on the outer periphery 31A of the carrier Ca outside the oil seal 50.

  Here, the space P1 outside the oil seal 50 is a sealed space (the external gear 12 and the internal gear) that is sealed by a member including the casing 17 and the carrier Ca among the two spaces separated by the oil seal 50. 16 is a space in which a speed reduction mechanism including 16 is not accommodated (a space in which a lubricant is enclosed). In other words, the space P1 outside the oil seal 50 refers to the space on the side opposite to the external gear of the oil seal 50. The space P1 outside the oil seal 50 corresponds to a space outside the space where the oil seal 50 is mainly sealed by the main lip portion 52A. If the space P1 outside the oil seal 50 focuses on the U-shaped seal wall 53 side (closed side) and the open side of the oil seal 50, and is further described, the space P1 is located on the seal wall 53 side (closed side). Corresponds to the facing space.

  The umbrella member 60 covers (a part of) the space P <b> 1 outside the oil seal 50, and prevents or reduces the direct contact of coolant with the oil seal 50. In this embodiment, the umbrella member 60 is provided integrally with the second member 42 of the machine tool connected to the first carrier body 31 of the carrier Ca. More specifically, the second member 42 has a flange portion 42F that faces an axial end surface (hereinafter simply referred to as a casing end surface) 17A of the casing 17. The flange portion 42F extends from the outer periphery 17C (of the end portion) of the casing 17 to the radially outer side by r (42-17C). The umbrella member 60 extends in the axial direction from the outer end portion of the flange portion 42F toward the casing 17 side.

  The umbrella member 60 extends to the outside of the casing 17 in the radial direction. The axial length of the umbrella member 60 is L60. The umbrella member 60 overlaps the casing 17 by L (60-17) when viewed from the radial direction. In this configuration example, the axial length L60 of the umbrella member 60 is longer than the axial length L50 of the oil seal 50. Specifically, the axial length L60 of the umbrella member 60 is approximately twice the axial length L50 of the oil seal 50 (L60≈2 · L50).

  The umbrella member 60 has a facing surface 60A that faces the carrier Ca (the first carrier body 31) (with the casing 17 therebetween). The facing surface 60A is inclined by α degrees with respect to the axis, and the inner diameter increases toward the axial end portion 60B. In this configuration example, the inner diameter of the facing surface 60A of the umbrella member 60 increases from D60A1 to D60A2 toward the axial end 60B (D60A1 <D60A2).

  The umbrella member 60 (the facing surface 60 </ b> A) faces the outer periphery 17 </ b> C (at the end) of the casing 17 with a gap. The outer periphery 17C (at the end) of the casing 17 is parallel to the axis, and the inner diameter of the facing surface 60A of the umbrella member 60 increases from D60A1 to D60A2 toward the axial end 60B. Therefore, the gap between the facing surface 60A of the umbrella member 60 and the outer periphery 17C of the casing 17 also increases from δ1 (60A-17C) to δ2 (60A-17C) toward the axial end 60B.

  On the other hand, an O-ring 70 is disposed on the outer periphery 31A of the carrier Ca (the first carrier body 31) outside the oil seal 50. The O-ring 70 is made of an elastic member. Therefore, for example, as in the configuration example of FIG. 5 to be described later, the O-ring 70 can remain on the outer periphery 31A of the first carrier body 31 only by its own elastic reaction force. However, in this configuration example, a ring-shaped O-ring groove 72 is formed at a position outside the oil seal 50 on the outer periphery 31 A of the first carrier body 31, and the O-ring 70 is disposed in the O-ring groove 72. ing.

  The axial width W72 of the O-ring groove 72 is smaller than the diameter d70 of the O-ring 70. That is, the O-ring 70 is partially fitted in the O-ring groove 72 and closes the O-ring groove 72. Therefore, the O-ring groove 72 according to this configuration example does not substantially function as a “ring-shaped groove (for coolant guidance) formed on the outer periphery 31A of the carrier Ca” described later. The O-ring 70 has a radial height of H70 from the outer periphery 31A of the carrier Ca (the first carrier body 31).

  The casing 17 and the O-ring 70 overlap each other when viewed from the radial direction. In this configuration example, the O-ring 70 entirely overlaps the casing 17 when viewed from the radial direction. In other words, the entire O-ring 70 is located closer to the axial oil seal 50 than the casing end surface 17A. Specifically, the end portion 70E on the axially opposite oil seal side of the O-ring 70 is positioned on the axial oil seal 50 side by L (17A-70E) from the casing end surface 17A. The center 70C in the axial direction of the O-ring 70 is positioned on the oil seal 50 side by L (17A-70C) from the casing end surface 17A. That is, the casing end surface 17A protrudes by L (17A-70C) outward in the axial direction from the axial center 70C of the O-ring 70.

  In the present configuration example, the facing surface 60A of the casing 17 and the (first) umbrella member 60 overlaps by L (60-17) when viewed from the radial direction, and the casing end surface 17A further includes a seal wall portion. It protrudes by L (17A-53A) in the axial direction from the wall end face 53A of 53. As a result, a labyrinth is formed in the path through which the coolant reaches the oil seal 50.

  A casing chamfered portion 17D is formed on the inner peripheral side of the casing end surface 17A of the casing 17.

  Next, the operation of this seal structure will be described.

  In this seal structure, an umbrella member 60 that covers the space P1 outside the oil seal 50 is provided. Therefore, the presence of the umbrella member 60 reduces the direct impact of the coolant on the oil seal 50.

  In addition, this seal structure includes an O-ring 70 disposed on the outer periphery 31A of the carrier Ca (first carrier body 31) outside the oil seal 50. The O-ring 70 is disposed on the outer periphery 31A of the first carrier body 31 of the carrier Ca with a radial height H70. Therefore, the coolant dripped from the umbrella member 60 (or the coolant that has passed through the umbrella member 60) can be guided to the lower side of the first carrier body 31 by the O-ring 70 without flowing to the oil seal 50 side. it can.

  As a result, it is possible to significantly prevent the coolant from entering the reduction gear 10 with one oil seal 50 and to prevent the oil seal 50 from being damaged by the coolant.

  In particular, in this configuration example, the umbrella member 60 has a facing surface 60A facing the carrier Ca (the first carrier body 31), and the facing surface 60A has an inner diameter of D60A1 toward the axial end portion 60B. From D60A2 to D60A2 (D60A1 <D60A2). As described above, in this embodiment, the speed reducer 10 is assembled to the machine tool with the axial direction oriented in the horizontal direction. Therefore, the facing surface 60A descends away from the oil seal 50 at an angle of α degrees with respect to the axis above the umbrella member 60. Thereby, the coolant that has fallen on the umbrella member 60 can be guided to the lower side of the outer periphery 31 </ b> A of the carrier Ca so as to be away from the oil seal 50. Further, below the umbrella member 60, the umbrella member 60 is lowered and opened to the outside at an angle of α degrees with respect to the axis. As a result, the coolant guided to the lower side of the outer periphery 31A of the carrier Ca can be discharged to the outside of the casing 17 by the inclination of the facing surface 60A. As a result, the coolant is difficult to reach the oil seal 50.

  In this configuration example, the umbrella member 60 is opposed to the outer periphery 17C (at the end) of the casing 17 with a gap δ (60A-17C). Moreover, the gap δ (60A-17C) increases from δ1 (60A-17C) to δ2 (60A-17C) toward the axial end 60B. Therefore, this configuration also makes it difficult for the coolant to reach the oil seal 50. Further, the member having the umbrella member 60 (the second member 42 in this example) can be easily assembled without interfering with the casing 17 on the speed reduction device 10 side. This configuration is particularly advantageous when a structure in which the umbrella member 60 and the casing 17 overlap each other when viewed from the radial direction is employed as in the present embodiment.

  In this configuration example, the casing 17 and the O-ring 70 are overlapped when viewed from the radial direction. As a result, most of the coolant dripping from the axial end portion 60 </ b> B of the casing 17 can be dropped to the outside in the axial direction (on the side opposite to the oil seal 50) than the O-ring 70. Contact can be suppressed. Particularly in this configuration example, the entire O-ring 70 overlaps the casing 17 when viewed from the radial direction. That is, the center 70C in the axial direction of the O-ring 70 is positioned on the inner side in the axial direction (on the oil seal 50 side) by L (17A-70C) from the casing end surface 17A. Therefore, most of the coolant dripping from the casing end surface 17 </ b> A can be dropped to the anti-oil seal side of the O-ring 70.

  In the present invention, various modifications can be considered in addition to the above configuration example.

  The modification shown in FIG. 3 differs from the configuration example shown in FIGS. 1 and 2 in that the O-ring 70 is not disposed in the O-ring groove 72. Since the O-ring 70 is not disposed, the O-ring groove 72 in the configuration example of FIGS. 1 and 2 can function as a ring-shaped groove 80 (for coolant guidance).

  That is, this modification includes a sealing member provided with an umbrella member 60 that covers the space P1 outside the oil seal 50, and a ring-shaped groove 80 formed on the outer periphery 31A of the carrier Ca outside the oil seal 50. Can be caught.

  Also with this sealing structure, the coolant that has dripped from the umbrella member 60 or the coolant that has passed through the umbrella member 60 is provided in the carrier Ca by the ring-shaped groove 80 disposed on the outer periphery 31A of the carrier Ca (the first carrier body 31). The effect of being guided to the lower side and discharged to the outside is obtained.

  Since this configuration does not include the O-ring 70, the cost can be further reduced. Thus, the “ring-shaped groove” may be provided together with the O-ring, or may be provided instead of the O-ring.

  The other configuration is the same as the configuration example of FIGS. Accordingly, the same or similar members are designated by the same reference numerals as those of the previous embodiment, and redundant description is omitted. The following embodiments are also the same.

  In the modified example shown in FIG. 4, the seal structure of the present invention is configured by performing an additional machining design change on a general reduction gear. In this configuration example, the casing 81 and the O-ring 70 do not overlap each other when viewed from the radial direction as compared to the configuration examples of FIGS. Specifically, the casing end surface 81A is flush with the wall end surface 53A of the seal wall portion 53 of the oil seal 50, and does not protrude from the wall end surface 53A.

  Further, the umbrella member is not integrally formed on the flange portion 43 </ b> F of the second member 43. That is, the umbrella member 76, which is a member different from the second member 43, is coupled to the flange portion 43 </ b> F where the umbrella member is not formed by the bolt 78. The umbrella member 76 is formed of a simple ring-shaped member, and is opposed to the outer periphery 81C of the casing 81 with a certain gap δ (76-81C).

  The umbrella member 76 has an extending portion (an opposing surface 76A in this example) extending in the axial direction, and the axial length L76A of the extending portion is larger than the axial length L50 of the oil seal 50 (L76A). > L50). The umbrella member 76 has a facing surface 76A that faces the carrier Ca, but the facing surface 76A is configured by a surface parallel to the axis. That is, the opposing surface 76A does not employ an inclined configuration in which the inner diameter increases toward the axial end 76B.

  With these configurations, in the modification shown in FIG. 4, the seal structure according to the present invention can be configured by additional processing on a general reduction gear and the second member, and the manufacturing cost can be reduced.

  Other configurations are the same as those of the configuration example of FIGS. That is, an O-ring 70 (with an O-ring groove 72) is arranged on the outer periphery 31A of the first carrier body 31 of the carrier Ca outside the oil seal 50.

  In the modification shown in FIG. 5, the casing protrusion 82 </ b> P, which is a part where the casing 82 protrudes, is secured larger than the oil seal 50 in the configuration example of FIGS. 1 and 2. Specifically, the end surface 82A of the casing 82 protrudes greatly from the wall end surface 53A of the oil seal 50 by L (82A-53A) outward in the axial direction. The axial length L (82A-53A) in which the casing protruding portion 82P extends in the axial direction is ½ or more of the axial length L50 of the oil seal 50, and provides a labyrinth effect with the umbrella member 60. It can be further enhanced.

  An O-ring 70 is disposed on the radially inner side of the large casing protrusion 82P (the outer periphery 31A of the first carrier body 31 of the carrier Ca outside the oil seal 50). The O-ring 70 is arranged without an O-ring groove. The O-ring 70 is positioned by coming into contact with the wall end surface 53 </ b> A of the seal wall 53 of the oil seal 50.

  Since the O-ring 70 is not fitted in the O-ring groove 72, the radial height H70h of the O-ring 70 from the outer periphery 31A of the carrier Ca is set in the O-ring groove 72 in FIGS. It can be secured higher than the O-ring height H70 (H70h> H70). In other words, even if the O-ring 70 having the same size as the O-ring 70 used in FIGS. 1 and 2 is used, the damming effect can be further enhanced.

  Similarly to the configuration example of FIG. 3, in the configuration example of FIG. 5, the O-ring groove 72 is deliberately placed in the O-ring groove 72 even though the O-ring groove 72 is disposed on the anti-oil seal 50 side of the O-ring 70. The ring 70 is not arranged. As a result, the O-ring groove 72 can function as a ring-shaped groove 80 for guiding the coolant. In this configuration example, the O-ring 70 and the ring-shaped groove 80 (O-ring groove 72) for guiding the coolant overlap the casing 82 when viewed from the radial direction. Further, the ring-shaped groove 80 is disposed outside the O-ring 70.

  The other configuration is the same as the configuration example described in FIGS.

  In the modification shown in FIG. 6, the umbrella member 90 is provided not in the second member 43 on the machine tool side but in the casing 92 of the speed reduction device 10 with respect to the configuration examples in FIGS. 1 and 2. The casing 92 includes, on the inner periphery 90A, a protrusion 90A1 that extends from the oil seal 50 and is flush with the fitting surface 92E of the oil seal 50 in parallel with the shaft, and an opposing surface 90A2 of the umbrella member 90. . The facing surface 90A2 has an inner diameter that increases toward the axial end portion 92B of the casing 92.

  The protrusion 90A1 and the facing surface 90A2 are connected by a connecting portion 90A3 and a chamfered portion 90A4 that are formed at right angles to the axis. The facing surface 90A2 faces the outer periphery 31A of the first carrier body 31 of the carrier Ca in the vicinity of the connecting portion 90A3. Note that the facing surface 90A2 also faces the outer periphery 43B of the second member 43 with a gap δ (90A2-43B) that increases as it approaches the axial end portion 92B.

  In the modification shown in FIG. 6, the coolant that has traveled along the facing surface 90 </ b> A <b> 2 of the umbrella member 90 collides with the connecting portion 90 </ b> A <b> 3, and the direction of the radially inner flow is changed to a right angle with the axis. The ring 70 can be guided to the anti-oil seal 50 side.

  Further, the facing surface 90A2 of the umbrella member 90 has an inner diameter that is increased toward the axial end portion 92B of the casing 92 (because the gap δ (90A2-43B) is increased). By the inclination, the coolant guided to the lower side of the speed reduction device 10 can be smoothly guided and discharged to the outside. Further, due to the inclination of the facing surface 90A2, even when the casing 92 of the speed reduction device 10 and the second member 43 of the machine tool overlap when viewed from the radial direction, the casing 92 and the second member 43 of the speed reduction device 10 do not overlap each other. Connection can be easily performed.

  Further, in this configuration example, it is not necessary to basically process the second member 43 in order to construct the seal structure, so that there is an advantage that the degree of freedom in construction is high.

  The other configuration is the same as the configuration example described in FIGS.

  In addition to the above-described modifications, various modifications can be considered in the present invention.

  For example, the shape and size of the umbrella member that covers the outside of the oil seal are not particularly limited to the above configuration example. All of the umbrella members described so far have a facing surface that faces the outer periphery of the carrier. However, depending on the direction in which the coolant flows, for example, the facing that faces only the casing and the mating member, not the carrier. An umbrella member having a surface may be used.

  A plurality of O-rings or ring-shaped grooves may be arranged or formed on the outer periphery of the carrier. Only a plurality of O-rings may be provided, or only a plurality of ring-shaped grooves may be provided, or a plurality of O-rings may be provided in a mixed state.

  The shape and size of the ring-shaped groove are not particularly limited. For example, in the configuration example described above, a ring-shaped groove having a V-shaped cross section passing through the shaft center is formed. For example, the cross-sectional shape passing through the shaft center is rectangular, arcuate, or U-shaped. Alternatively, a ring-shaped groove having a shape or a combination of these may be formed.

  Further, in the above configuration example, an eccentric oscillating speed reduction device is shown as an example of the device. However, the seal structure according to the present invention provides oil between the casing and the carrier that rotates relative to the casing. As long as the seal is provided, the applied device is not limited to the eccentric oscillating speed reduction device. For example, a simple planetary reduction device may be used. Furthermore, it is not necessary to be a reduction gear, and for example, a rotation device with constant input / output may be used.

DESCRIPTION OF SYMBOLS 17 ... Casing 17A ... Casing end surface 31A ... Outer periphery 50 ... Oil seal 60 ... Umbrella member 60A ... Opposite surface 70 ... O-ring 80 ... Ring-shaped groove | channel Ca ... Carrier P1 ... Space

Claims (9)

In a seal structure comprising a casing, a carrier that rotates relative to the casing, and an oil seal disposed between the casing and the carrier,
An umbrella member covering a space outside the oil seal;
An O-ring disposed on the outer periphery of the carrier outside the oil seal. In a seal structure comprising a casing, a carrier that rotates relative to the casing, and an oil seal disposed between the casing and the carrier,
An umbrella member covering a space outside the oil seal;
A seal structure comprising: a ring-shaped groove formed on an outer periphery of the carrier outside the oil seal. In claim 1 or 2,
The umbrella member has a facing surface facing the carrier,
The opposed structure has an inner diameter that increases toward an end in the axial direction. In any one of Claims 1-3,
The said umbrella member has a clearance gap between the said casing and the outer periphery of this casing, and has opposed. The sealing structure characterized by the above-mentioned. In any one of Claims 1, 3, and 4,
The casing and the O-ring are overlapped when viewed from the radial direction. In any one of Claims 2-4,
The seal structure, wherein the casing and the ring-shaped groove overlap each other when viewed from the radial direction. In any one of Claims 1 and 3-5,
A seal structure in which a ring-shaped groove is formed on the outer periphery of the carrier outside the O-ring. An external gear, an internal gear meshing with the external gear, a casing provided with the internal gear, a carrier rotating relative to the casing, and an oil seal disposed between the casing and the carrier And a gear device comprising:
An umbrella member covering the space on the anti-external gear side of the oil seal;
A gear device comprising: an O-ring disposed on an outer periphery of the carrier on a side opposite to the external gear than the oil seal. An external gear, an internal gear meshing with the external gear, a casing provided with the internal gear, a carrier rotating relative to the casing, and an oil seal disposed between the casing and the carrier And a gear device comprising:
An umbrella member covering the space on the anti-external gear side of the oil seal;
A gear device comprising: a ring-shaped groove formed on an outer periphery of the carrier on a side opposite to the external gear than the oil seal.

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