JP2018128128A - Eccentric oscillation type gear device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a strength of a crankshaft further high without enlarging an outer diameter of the crankshaft more than needed.SOLUTION: An eccentric oscillation type gear device G1 comprises: oscillation gears 12A and 12B; a crankshaft 20; a first carrier 30A and a second carrier 30B; first and second bearings 66A and 66B which are disposed between the first and second carriers and the crankshaft; and an input gear 50 which is provided in an end of the crankshaft closer to the first carrier. The eccentric oscillation gear device also comprises movement regulation means which regulates movements of the crankshaft to both sides in an axial direction. The movement regulation means includes: a crankshaft first stopper ring 24B fitted to a crankshaft second groove 23B which is provided in an end of the crankshaft closer to the second carrier; and a carrier second stopper ring 34B fitted into a carrier second groove 33B which is provided in the second carrier. The crankshaft does not include a small diameter part of which the outer diameter is smaller than a crankshaft first bearing part 25A in which the first bearing is disposed and which is functioned as a constituent of the movement regulation means between the crankshaft first bearing part and the input gear.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an eccentric oscillating gear device.

  Patent Document 1 discloses an eccentric oscillating gear device in which an oscillating external gear internally meshes with an internal gear.

  The gear device includes a crankshaft for swinging the external gear, a first carrier disposed on one axial side of the external gear, a second carrier disposed on the other axial side of the external gear, have. A first bearing is disposed between the first carrier and the crankshaft. A second bearing is disposed between the second carrier and the crankshaft. An input gear for inputting power to the crankshaft is provided at the end of the crankshaft on the first carrier side.

  In this gear device, the movement of the crankshaft in the axial direction relative to the first carrier and the second carrier is transferred to the retaining ring fitted in the groove formed in the crankshaft and the groove formed in the first carrier and the second carrier. It is regulated by the fitted retaining ring.

JP 2014-55654 A (FIG. 1)

  In this type of gear device, maintaining the strength of the crankshaft properly is one of important design matters. An object of the present invention is to maintain the strength of the crankshaft higher without increasing the outer diameter of the crankshaft.

  The present invention includes an oscillating gear, a crankshaft for oscillating the oscillating gear, a first carrier arranged on one axial side of the oscillating gear, and an axially other side of the oscillating gear. A second carrier, a first bearing disposed between the first carrier and the crankshaft, a second bearing disposed between the second carrier and the crankshaft, and the crankshaft An eccentric oscillating gear device comprising an input gear provided at an end of the first carrier side of the first carrier side, and having a movement restricting means for restricting movement of the crankshaft in both axial directions, The movement restricting means includes a crankshaft second groove provided at an end of the crankshaft on the second carrier side, a crankshaft second retaining ring fitted in the crankshaft second groove, and the second carrier. The carrier second groove provided on the carrier and fitted in the carrier second groove A second retaining ring, the crankshaft has a crankshaft first bearing portion on which the first bearing is disposed, and the crankshaft is connected to the crankshaft first bearing portion and the input. The above-described problem is solved by adopting a configuration in which a small-diameter portion having an outer diameter smaller than that of the first crankshaft bearing portion functioning as a component of the movement restricting unit is not provided with the gear.

  In the axial direction of the crankshaft, if there is a small diameter portion formed to restrict the movement of the crankshaft in the axial direction between the first bearing and the input gear, the strength of the crankshaft is greatly affected.

  The present invention focuses on this point. The crankshaft according to the present invention does not have a small-diameter portion between the first bearing and the input gear that has a smaller outer diameter than the arrangement portion of the first bearing in order to restrict axial movement. For this reason, the strength of the crankshaft can be maintained higher.

  According to the present invention, the strength of the crankshaft can be maintained higher without increasing the outer diameter of the crankshaft.

1 is an overall cross-sectional view showing an example of an eccentric oscillating gear device according to an embodiment of the present invention. 1 is an enlarged cross-sectional view of the main part of FIG. Sectional drawing equivalent to FIG. 2 which shows the example of the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. Sectional drawing equivalent to FIG. 2 which shows the example of the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention.

  Hereinafter, an example of an embodiment of the present invention will be described in detail based on the drawings.

  FIG. 1 is an overall cross-sectional view showing an example of an eccentric oscillating gear device G1 according to an embodiment of the present invention, and FIG.

  The gear device G1 includes a first external gear 12A and a second external gear 12B disposed adjacent to the first external gear 12A in the axial direction as swing gears. The first external gear 12 </ b> A and the second external gear 12 </ b> B are in mesh with the internal gear 16. Further, the gear device G1 is disposed on one side in the axial direction of the crankshaft 20 that swings the first external gear 12A and the second external gear 12B, and the first external gear 12A and the second external gear 12B. The first carrier 30A and the second carrier 30B disposed on the other side in the axial direction of the first external gear 12A and the second external gear 12B.

  The gear device G1 is configured to extract the relative rotation of the first external gear 12A and the second external gear 12B with respect to the internal gear 16 from the first carrier 30A and the second carrier 30B via the crankshaft 20. .

  More specific description will be given below.

  First, the outline of the gear device G1 will be described.

  The gear device G1 includes a plurality of crankshafts 20 (three in this example: only one is shown in FIG. 1) for swinging the first external gear 12A and the second external gear 12B. The crankshaft 20 is arranged at an interval of 120 degrees in the circumferential direction at a position offset by δ20 from the axis C16 of the internal gear 16.

  Each crankshaft 20 includes an input gear 50 at the end on the first carrier 30A side. The input gear 50 meshes with the drive source side pinion (not shown) disposed at the position of the axis C16 of the internal gear 16. An inner spline 51 for transmitting power from the drive source side to the crankshaft 20 is formed on the inner periphery of the input gear 50.

  An outer spline 21 that engages with the inner spline 51 of the input gear 50 and grooves 78 and 79 are formed at the end of the crankshaft 20 on the carrier side. The input gear 50 is restricted from moving along the axial direction of the crankshaft 20 by retaining rings 81 and 82 fitted in the grooves 78 and 79.

  Each crankshaft 20 is integrally formed with a first eccentric body 52A that swings the first external gear 12A and a second eccentric body 52B that swings the second external gear 12B (separate body). The first eccentric body and the second eccentric body configured in the above may be connected to the crankshaft via a key or the like).

  The first eccentric body 52A and the second eccentric body 52B have shaft centers C52A and C52B that are eccentric with respect to the shaft center C20 of the crankshaft 20, respectively. The eccentric phase difference between the first eccentric body 52A and the second eccentric body 52B is 180 degrees in this example (eccentric in a direction away from each other).

  The three crankshafts 20 have the same configuration, and the first eccentric bodies 52A formed at the same position in the axial direction of each crankshaft 20 have the same eccentric phase. The second eccentric bodies 52B formed at the same position in the axial direction of each crankshaft 20 are also aligned in eccentric phase.

  A first eccentric bearing 56A is disposed between the first eccentric body 52A and the first external gear 12A. A second eccentric bearing 56B is disposed between the second eccentric body 52B and the second external gear 12B.

  In the gear device G 1, the internal gear 16 is rotatably incorporated in an internal gear main body 17 integrated with the casing 62 and a pin groove 18 formed in the internal gear main body 17. And a cylindrical pin member 19 constituting the inner teeth. The number of teeth of the internal gear 16 (the number of pin members 19) is slightly larger (by 1 in this example) than the number of teeth of the first external gear 12A and the second external gear 12B.

  A first main bearing 74A is disposed between the casing 62 of the gear device G1 and the first carrier 30A. A second main bearing 74B is disposed between the casing 62 and the second carrier 30B. In the gear device G1, the first main bearing 74A and the second main bearing 74B are formed of angular ball bearings that are assembled back to back. The first main bearing 74A and the second main bearing 74B have a dedicated first main bearing outer ring 74A1 and a second main bearing outer ring 74B1, but do not have a dedicated inner ring. The inner ring of the first main bearing 74A is constituted by a carrier first main rolling surface 37A formed on the first carrier 30A. The inner ring of the second main bearing 74B is constituted by a carrier second main rolling surface 37B formed on the second carrier 30B.

  A carrier pin 31 protrudes from the second carrier 30B toward the first carrier 30A. The carrier pin 31 penetrates the first external gear 12A and the second external gear 12B in a non-contact manner. The first carrier 30 </ b> A and the second carrier 30 </ b> B are connected and integrated by a bolt 76 via the carrier pin 31.

  In the gear device G1, for example, a first arm (not shown) of a robot is connected to the casing 62 via a bolt (only the bolt hole 75 is shown). For example, a second arm (not shown) of the robot is connected to the second carrier 30B via a bolt (only the tap hole 32 is shown).

  Referring mainly to FIG. 2, the first carrier 30A is arranged on one side in the axial direction of the first external gear 12A and the second external gear 12B. A second carrier 30B is disposed on the other side in the axial direction of the first external gear 12A and the second external gear 12B. A first bearing 66A is disposed between the first carrier 30A and the crankshaft 20. A second bearing 66B is disposed between the second carrier 30B and the crankshaft 20. That is, the crankshaft 20 is supported by the first carrier 30A and the second carrier 30B via the first bearing 66A and the second bearing 66B.

  The first bearing 66A includes a first roller 66A1 as a rolling element and a first retainer 66A2 that holds the first roller 66A1. The first bearing 66A does not have a dedicated inner and outer ring. The crankshaft 20 (the crankshaft first bearing portion 25A) also serves as the inner ring of the first bearing 66A, and the first carrier 30A (the carrier first bearing portion 35A) also serves as the outer ring of the first bearing 66A.

  The second bearing 66B includes a second roller 66B1 as a rolling element and a second retainer 66B2 that holds the second roller 66B1. The second bearing 66B does not have a dedicated inner / outer ring. The crankshaft 20 (the crankshaft second bearing portion 25B) also serves as the inner ring of the second bearing 66B, and the second carrier 30B (the carrier second bearing portion 35B) also serves as the outer ring of the second bearing 66B.

  The first eccentric bearing 56A disposed between the first eccentric body 52A and the first external gear 12A holds the first eccentric bearing roller 56A1 as a rolling element and the first eccentric bearing roller 56A1. The first eccentric bearing retainer 56A2 is provided. The first eccentric bearing 56A also has no dedicated inner and outer rings. The first eccentric body 52A also serves as the inner ring of the first eccentric bearing 56A, and the first external gear 12A (the crankshaft through hole 12A1 thereof) also serves as the outer ring of the first eccentric bearing 56A.

  The second eccentric bearing 56B disposed between the second eccentric body 52B and the second external gear 12B also has a second eccentric bearing roller 56B1 as a rolling element and a second eccentric bearing roller 56B1 that holds the second eccentric bearing roller 56B1. An eccentric bearing retainer 56B2 is provided. The second eccentric bearing 56B also has no dedicated inner and outer rings. The second eccentric body 52B also serves as the inner ring of the second eccentric bearing 56B, and the second external gear 12B (the crankshaft through hole 12B1 thereof) also serves as the outer ring of the second eccentric bearing 56B. In the present specification, the concept of “roller” includes the concept of “needle”.

  The first retainer 66A2 of the first bearing 66A and the first eccentric bearing retainer 56A2 of the first eccentric bearing 56A are in contact with each other via the first sliding ring 70A. The first slip ring 70 </ b> A is in contact with the first eccentric body step portion 27 </ b> A of the crankshaft 20. The first eccentric bearing retainer 56A2 of the first eccentric bearing 56A and the second eccentric bearing retainer 56B2 of the second eccentric bearing 56B are in contact with each other via the central sliding ring 72. The second eccentric bearing retainer 56B2 of the second eccentric bearing 56B and the second retainer 66B2 of the second bearing 66B are in contact with each other via the second sliding ring 70B. The second sliding ring 70B is in contact with the second eccentric body step portion 27B of the crankshaft 20.

  Here, the structure regarding the movement restriction | limiting of the axial direction of the crankshaft 20 is demonstrated in detail.

  As described above, the crankshaft 20 is supported by the first carrier 30A via the first bearing 66A and supported by the second carrier 30B via the second bearing 66B.

  The first carrier 30A is positioned on one axial direction side (input gear 50 side) of the first external gear 12A, and the carrier first bearing portion 35A in which the first bearing 66A is disposed is connected to the shaft of the first carrier 30A. The direction first external gear 12A is provided. The second carrier 30B is located on the other axial side (counter input gear side) of the second external gear 12B, and the carrier second bearing portion 35B in which the second bearing 66B is disposed is connected to the shaft of the second carrier 30B. It has in the direction 2nd external gear 12B side.

  Here, the carrier first bearing portion refers to a portion where the outer ring of the first bearing faces the first carrier. When the first bearing 66A is like the present gear device G1 having no outer ring, the carrier first bearing portion 35A is the first roller 66A1 that is a rolling element of the first bearing 66A when viewed from the radial direction. The part projected on the carrier 30A side is indicated. Similarly, the carrier second bearing portion refers to a portion where the outer ring of the second bearing faces the second carrier. When the second bearing 66B is the gear device G1 having no outer ring, the carrier second bearing portion 35B is a second roller 66B1 that is a rolling element of the second bearing 66B when viewed from the radial direction. The part projected on the carrier 30B side is indicated.

  On the other hand, the crankshaft 20 has a crankshaft first bearing portion 25A in which the first bearing 66A is disposed at a position facing the carrier first bearing portion 35A. Further, the crankshaft 20 has a crankshaft second bearing portion 25B in which the second bearing 66B is disposed at a position facing the carrier second bearing portion 35B.

  Here, the crankshaft first bearing portion refers to a portion where the inner ring of the first bearing faces the crankshaft. When the first bearing 66A is like the present gear device G1 having no inner ring, the crankshaft first bearing portion 25A cranks the first roller 66A1 that is a rolling element of the first bearing 66A when viewed from the radial direction. The part projected on the axis 20 side is indicated. Similarly, the crankshaft second bearing portion refers to a portion where the inner ring of the second bearing faces the crankshaft. When the second bearing 66B is like the present gear device G1 having no inner ring, the crankshaft second bearing portion 25B cranks the second roller 66B1 that is a rolling element of the second bearing 66B when viewed from the radial direction. The part projected on the axis 20 side is indicated.

  The movement restriction means of the crankshaft 20 of the gear device G1 includes a crankshaft second groove 23B provided at the end of the crankshaft 20 on the second carrier 30B side, and a crank fitted in the crankshaft second groove 23B. A shaft second retaining ring 24B is provided. The movement restricting means includes a carrier second groove 33B provided in the second carrier 30B (a carrier second large diameter portion 38B described later) and a carrier second retaining ring 34B fitted in the carrier second groove 33B. It has.

  The second carrier 30B includes the carrier second bearing portion 35B in which the second bearing 66B is disposed, and a carrier second large diameter portion 38B in which the carrier second retaining ring 34B is disposed. The carrier second groove 33B is formed in the carrier second large diameter portion 38B.

  The inner diameter (radius: same below) R38B of the carrier second large diameter portion 38B is larger than the inner diameter R35B of the carrier second bearing portion 35B by a diameter difference δ (35B-38B). Therefore, a carrier second step portion 36B having the diameter difference δ (35B-38B) is formed between the carrier second bearing portion 35B and the carrier second large diameter portion 38B.

  The crankshaft 20 includes a crankshaft second bearing portion 25B in which the second bearing 66B is disposed, and a crankshaft second small diameter portion 28B in which the crankshaft second retaining ring 24B is disposed. The crankshaft second groove 23B is formed in the crankshaft second small diameter portion 28B.

  The outer diameter (radius: same below) r28B of the crankshaft second small diameter portion 28B is smaller than the outer diameter r25B of the crankshaft second bearing portion 25B by a diameter difference δ (25B-28B). Therefore, a crankshaft second step portion 26B having a diameter difference δ (25B−28B) is formed between the crankshaft second bearing portion 25B and the crankshaft second small diameter portion 28B.

  The second ring member 73B spans between the crankshaft second retaining ring 24B and the crankshaft second step portion 26B, and between the carrier second retaining ring 34B and the carrier second step portion 36B. Has been placed.

  As described above, in the gear device G1, the carrier second groove 33B, the carrier second retaining ring 34B, the carrier second step portion 36B, the crankshaft second groove 23B, the crankshaft are used as components of the movement restricting means of the crankshaft 20. A second retaining ring 24B, a crankshaft second step portion 26B, and a second ring member 73B are provided.

  On the other hand, on the first carrier 30A side of the crankshaft 20, as described above, the outer spline 21 for connecting the input gear 50 and the grooves 78 and 79 into which the retaining rings 81 and 82 are fitted are formed. Thus, the movement restrictions in the axial direction of the crankshaft 20 are all completed on the second carrier 30B side of the crankshaft 20 in both directions on both sides in the axial direction. At the position closer to the input gear 50 than the crankshaft first bearing portion 25A (between the crankshaft first bearing portion 25A and the input gear 50), there are no components that function as components of the movement restricting means. Absent.

  In other words, the axial movement of the crankshaft 20 is restricted to a position closer to the input gear 50 than the crankshaft first bearing portion 25A (between the crankshaft first bearing portion 25A and the input gear 50). For this reason, there is no small-diameter portion having an outer diameter smaller than that of the first crankshaft bearing portion 25A.

  The first carrier 30A includes a carrier first bearing portion 35A in which the first bearing 66A is disposed and an inner diameter of the carrier first bearing portion 35A provided on the axial input gear 50 side of the carrier first bearing portion 35A. A carrier first large diameter portion 38A having an inner diameter R38A larger than the diameter R35A by a diameter difference δ (35A-38A). Between the carrier first bearing portion 35A and the carrier first large diameter portion 38A, a carrier first step portion 36A having the diameter difference δ (35A-38A) is formed. A carrier first groove 33A is formed in the carrier first large diameter portion 38A. A carrier first retaining ring 34A is fitted in the carrier first groove 33A. A first ring member 73A that faces the first bearing 66A is disposed between the carrier first retaining ring 34A and the first carrier step 36A. The first ring member 73A faces the first bearing 66A (the first retainer 66A2) and restricts the axial movement of the first bearing 66A.

  Next, the operation of the gear device G1 will be described. First, the operation relating to the power transmission of the gear device G1 will be briefly described.

  When a drive source side pinion (not shown) arranged at the position of the axis C16 of the internal gear 16 rotates, the three input gears 50 meshed simultaneously with the drive source side pinion have the same rotational speed in the same direction. Rotate with. As a result, each input gear 50 and the three crankshafts 20 connected via the inner spline 51 and the outer spline 21 rotate at the same rotational speed in the same direction.

  As a result, the first external gear 12A swings and rotates through the first eccentric body 52A having the same phase in each crankshaft 20. Further, the second external gear 12B swings and rotates through the second eccentric body 52B whose phase is aligned with the first eccentric body 52A by a phase difference of 180 degrees.

  The first external gear 12A and the second external gear 12B are in mesh with the internal gear 16, and the number of teeth of the internal gear 16 (the number of pin members 19) is the first external gear 12A. And 1 more than the number of teeth of the second external gear 12B. Accordingly, the first external gear 12A and the second external gear 12B are rotated once each time the crankshaft 20 rotates once (every time the first eccentric body 52A and second eccentric body 52B rotate eccentrically once). It swings, and the phase is shifted from the internal gear 16 by a difference in the number of teeth (one gear in this gear device G1).

  As a result, the crankshaft 20 passing through the first external gear 12 </ b> A and the second external gear 12 </ b> B revolves around the axis C <b> 16 of the internal gear 16. This revolution is transmitted to the first carrier 30A and the second carrier 30B that support the crankshaft 20 via the first bearing 66A and the second bearing 66B. When the first carrier 30A and the second carrier 30B rotate, the second arm of the robot connected to the second carrier 30B rotates relative to the first arm of the robot connected to the casing 62.

  Here, the crankshaft 20 is provided to the crankshaft second retaining ring 24B fitted to the crankshaft second groove 23B provided at the end of the crankshaft 20 on the second carrier 30B side, and the second carrier 30B. The movement of the crankshaft 20 toward the first carrier 30A in the axial direction through the second ring member 73B is restricted by the carrier second step portion 36B.

  Further, the crankshaft 20 is connected to the second axial carrier through the second ring member 73B by the second crankshaft step portion 26B of the crankshaft 20 and the carrier second retaining ring 34B provided on the second carrier 30B. Movement to the 30B side is restricted.

  That is, the movement restricting means of the gear device G1 realizes the movement restriction of the crankshaft 20 to both sides in the axial direction only by the movement restricting means provided on the side opposite to the first carrier in the axial direction of the second bearing 66B. .

  Various loads from the input gear 50, the first bearing 66A, the second bearing 66B, the first eccentric bearing 56A, the second eccentric bearing 56B, and the like are constantly applied to the crankshaft 20 of this type of gear device G1. In particular, the position on the input gear 50 side relative to the crankshaft first bearing portion 25A (between the crankshaft first bearing portion 25A and the input gear 50) is from the input gear 50 side where the crankshaft 20 is to be rotated. Strong torsional stress is generated by the driving torque and the reaction torque from the first eccentric bearing 56A and the second eccentric bearing 56B. Further, since the input gear 50 is provided at a portion protruding from the first bearing 66A in a cantilever state, the bending stress and the shear stress with respect to torque transmission and eccentric oscillation are also compared with other positions of the crankshaft 20. Tend to occur more frequently. For this reason, the position closer to the input gear 50 than the crankshaft first bearing portion 25 </ b> A is more severe in strength than the other positions of the crankshaft 20.

  However, in this gear device G1, a small-diameter portion having an outer diameter smaller than that of the crankshaft first bearing portion 25A is present at this portion for the purpose of restricting at least the axial movement of the crankshaft 20. Absent. Therefore, it is possible to obtain the gear device G1 having a higher strength of the crankshaft 20 correspondingly.

  Further, in the present gear device G1, from the viewpoint of “restricting the axial movement of the first bearing 66A”, the position of the crankshaft 20 on the input gear 50 side relative to the crankshaft first bearing portion 25A (the crankshaft first Between the bearing portion 25A and the input gear 50), no small diameter portion having an outer diameter smaller than that of the crankshaft first bearing portion 25A is formed. That is, in the gear device G1, the strength does not decrease at a position closer to the input gear 50 than the crankshaft first bearing portion 25A also in terms of axial positioning of the first bearing 66A.

  For the configuration of “restricting the axial movement of the first bearing 66A”, for example, a modification as shown in FIG. 3 may be adopted. In the gear device G2 illustrated in FIG. 3, the input gear 150 includes a protruding portion 151 that protrudes toward the first bearing 66A. The protrusion 151 faces the first retainer 66A2 of the first bearing 66A via the washer 154, and restricts the axial movement of the first bearing 66A. The input gear 150 is fixed to the end of the crankshaft 120 by bolts 153. The other configuration is the same as that of the gear device G1 (in FIG. 3, parts corresponding to those in FIG. 2 are given the same reference numerals).

  Also with such a configuration, the crankshaft of the crankshaft 120 is positioned at a position closer to the input gear 150 than the crankshaft first bearing portion 25A of the crankshaft 120 (between the crankshaft first bearing portion 25A and the input gear 150). The axial movement of the first bearing 66A can be restricted without forming any small-diameter portion whose outer diameter is smaller than that of the first bearing portion 25A.

  It should be noted that “from the crankshaft first bearing portion that functions as a component of the movement restricting means at a position closer to the input gear than the crankshaft first bearing portion (between the crankshaft first bearing portion 25A and the input gear 150). The configuration that realizes that “the outer diameter does not have a small diameter portion” is not limited to the configuration of the gear devices G1 and G2.

  For example, in the gear device G1 shown in FIGS. 1 and 2, the carrier first step portion 36A is provided between the carrier first bearing portion 35A and the carrier first large diameter portion 38A. The carrier first retaining ring 34A is fitted in a carrier first groove 33A provided in the carrier first large diameter portion 38A. The first ring member 73A opposes the first retainer 66A2 of the first bearing 66A and is disposed between the carrier first retaining ring 34A and the carrier first step portion 36A. Further, the first slip ring 70A faces the first retainer 66A2 of the first bearing 66A and faces the first eccentric body step portion 27A of the crankshaft 20.

  Therefore, the crankshaft 20 includes a first carrier step 36A, a first carrier retaining ring 34A, a first ring member 73A, and a first sliding ring 70A (via the first retainer 66A2 of the first bearing 66A). , The movement toward the first carrier 30A side (the input gear 50 side) in the axial direction is also restricted.

  Accordingly, in the gear device G1 of FIGS. 1 and 2, for example, the carrier second step portion 36B may not be provided. That is, the carrier second groove 33B and the carrier second retaining ring 34B are provided on a surface having the same inner diameter as the carrier second bearing portion 35B, and the second ring member 73B is provided with the second retainer 66B2 and the crankshaft of the second bearing 66B. It is good also as a structure which opposes the 2nd step part 26B.

  In this case as well, the movement of the crankshaft 20 in both axial directions can be restricted, and the position closer to the input gear 50 than the crankshaft first bearing portion 25A (the crankshaft first bearing portion 25A and the input gear 50 In the meantime, for the purpose of restricting the movement of the crankshaft 20 in the axial direction, there is no portion having an outer diameter smaller than that of the crankshaft first bearing portion 25A. Therefore, it is possible to obtain the gear device G1 having a higher strength of the crankshaft 20 correspondingly.

  Furthermore, in order to implement | achieve the movement control to the axial direction both sides of the crankshaft 20, the structure of the gear apparatus G3 as shown in FIG. 4 is also employable.

  In the gear device G3, the first bearing 266A has a dedicated first outer ring 266A3 and first inner ring 266A4. The second bearing 266B also has a dedicated second outer ring 266B3 and second inner ring 266B4.

  The first bearing 266A having the dedicated first outer ring 266A3 and first inner ring 266A4 is restricted in the relative movement in the axial direction between the first outer ring 266A3 and the first inner ring 266A4. The second bearing 266B having the dedicated second outer ring 266B3 and second inner ring 266B4 is also restricted in the relative movement in the axial direction between the second outer ring 266B3 and the second inner ring 266B4.

  The movement restricting means for restricting the movement of the crankshaft 220 to both sides in the axial direction is based on the assumption that such a first bearing 266A and a second bearing 266B are provided, and the crankshaft first fitted in the crankshaft second groove 223B. In addition to the second retaining ring 224B and the carrier second retaining ring 234B fitted in the carrier second groove 233B, the carrier first groove 233A provided in the first carrier 230A and the carrier first groove 233A are fitted. It has a carrier first retaining ring 234A.

  The crankshaft second retaining ring 224B faces the second inner ring 266B4 of the second bearing 266B, and the carrier second retaining ring 234B faces the second outer ring 266B3 of the second bearing 266B, and the carrier first retaining ring. 234A faces the first outer ring 266A3 of the first bearing 266A.

  In this gear device G3, the first outer ring 266A3 of the first bearing 266A is opposed to the first eccentric bearing retainer 256A2 of the first eccentric bearing 256A. The first inner ring 266A4 of the first bearing 266A is opposed to a first eccentric body step portion 227A provided between the crankshaft first bearing portion 225A and the first eccentric body 252A.

  The second outer ring 266B3 of the second bearing 266B faces the second eccentric bearing retainer 256B2 of the second eccentric bearing 256B. The second inner ring 266B4 of the second bearing 266B is opposed to a second eccentric step 227B provided between the crankshaft second bearing portion 225B and the second eccentric body 252B.

  Further, the first outer ring 266A3 of the first bearing 266A and the second outer ring 266B3 of the second bearing 266B have the first eccentric bearing retainer 256A2 and the second eccentricity of the first eccentric bearing 256A with the central ring member 272 sandwiched in the center in the axial direction. The second eccentric bearing retainer 256B2 of the bearing 256B is sandwiched.

  On the other hand, in the gear device G3, the carrier first groove 233A and the carrier first retaining ring 234A are provided on a surface having the same inner diameter as the carrier first bearing portion 235A. The carrier second groove 233B and the carrier second retaining ring 234B are also provided on the surface having the same inner diameter as the carrier second bearing portion 235B.

  Also in the gear device G3, the axial movement of the crankshaft 220 is restricted at a position closer to the input gear 250 than the crankshaft first bearing portion 225A (between the crankshaft first bearing portion 225A and the input gear 250). For this purpose, there is no small diameter portion having an outer diameter smaller than that of the crankshaft first bearing portion 225A.

  Further, in this gear device G3, neither the first carrier 230A nor the second carrier 230B is provided with the first carrier step or the second carrier step, so that the first carrier 230A and the second carrier 230B are manufactured. Is easy.

  In particular, the vicinity of the first main bearing 274A of the first carrier 230A (or the vicinity of the second main bearing 274B of the second carrier 230B) is the carrier first main rolling surface 237A of the first main bearing 274A (or the second main bearing 274A). The hardness is maintained so as to function as the carrier second main rolling surface 237B) of the bearing 274B. For this reason, for example, in the case of the configuration of the gear device G1 in FIGS. 1 and 2, high machining accuracy is required in the vicinity of the first main bearing 74A or the second main bearing 74B in which high hardness is maintained. The carrier first bearing portion 35A or the carrier second bearing portion 35B (which functions as a rolling surface) needs to be formed, and labor, time, and cost are required for processing the first carrier 30A and the second carrier 30B.

  However, in this gear device G3, the carrier first bearing portion 235A and the carrier second bearing portion 235B do not constitute the rolling surfaces of the first roller 266A1 and the second roller 266B1, and therefore the first carrier 230A. In addition, the labor, time, and cost of processing the second carrier 230B can be reduced.

  In the gear device G3, the first outer ring 266A3 of the first bearing 266A is opposed to the first eccentric bearing retainer 256A2 of the first eccentric bearing 256A, and the second outer ring 266B3 of the second bearing 266B is the second eccentric. Opposing to the second eccentric bearing retainer 256B2 of the bearing 256B (the first inner ring 266A4 of the first bearing 266A and the second inner ring 266B4 of the second bearing 266B are opposed to the first eccentric bearing retainer 256A2 and the second eccentric bearing retainer 256B2. May be configured).

  Thereby, the movement of the crankshaft 220 to both axial sides can be more reliably regulated. Since other configurations and operations are the same as those of the gear device G1, the lower two digits in FIG. 4 corresponding to those in FIG. 2 are given the same reference numerals, and redundant description is omitted.

  In the above-described embodiment, there is a distribution type eccentric oscillating gear device having a plurality of crankshafts that oscillate the first external gear and the second external gear at positions offset from the axis of the internal gear. It was adopted. However, in addition to this, the eccentric oscillating gear device includes only one crankshaft on the axis of the internal gear, and the external gear and the internal gear via a columnar portion protruding from the carrier side. A gear device of a type called a center crank type that takes out the relative rotation of the shaft is also known.

  In the above embodiment, the externally oscillating eccentric oscillating gear device in which the first external gear and the second external gear oscillate with respect to the internal gear (in a fixed state). Was shown. However, among the eccentric oscillating gear devices, an internal oscillating type eccentric oscillating gear device in which an internal gear oscillates with respect to an external gear by a crankshaft is also known.

  The present invention can be applied to any type of an eccentric oscillating gear device in which an input gear for transmitting power to the crankshaft is provided at the end of the crankshaft for oscillating the oscillating gear on the first carrier side. The present invention can also be applied to the eccentric oscillating gear device, and the same effect can be obtained.

G1 ... Gear device 12A ... First external gear (oscillating gear)
12B ... Second external gear (oscillating gear)
DESCRIPTION OF SYMBOLS 20 ... Crankshaft 30A ... 1st carrier 30B ... 2nd carrier 66A ... 1st bearing 66B ... 2nd bearing 50 ... Input gear 23B ... Crankshaft 2nd groove | channel 24B ... Crankshaft 2nd retaining ring 33B ... Carrier 2nd groove | channel 34B ... Carrier second retaining ring 25A ... Crankshaft first bearing portion 25B ... Crankshaft second bearing portion

Claims (6)

An oscillating gear, a crankshaft for oscillating the oscillating gear, a first carrier arranged on one axial side of the oscillating gear, and a second carrier arranged on the other axial side of the oscillating gear A carrier, a first bearing disposed between the first carrier and the crankshaft, a second bearing disposed between the second carrier and the crankshaft, and the first of the crankshaft. An eccentric oscillating gear device comprising an input gear provided at an end on the carrier side,
A movement restricting means for restricting movement of the crankshaft to both sides in the axial direction;
The movement restricting means includes a crankshaft second groove provided at an end of the crankshaft on the second carrier side, a crankshaft second retaining ring fitted in the crankshaft second groove, and the second A carrier second groove provided in the carrier, and a carrier second retaining ring fitted in the carrier second groove;
The crankshaft has a crankshaft first bearing portion on which the first bearing is disposed, and the crankshaft is disposed between the crankshaft first bearing portion and the input gear and the movement restricting means. An eccentric oscillating gear device characterized by not having a small-diameter portion having an outer diameter smaller than that of the first crankshaft bearing portion functioning as a component. The eccentric oscillating gear device according to claim 1,
The second carrier includes a carrier second bearing portion in which the second bearing is disposed, a carrier second large diameter portion in which an inner diameter is larger than the carrier second bearing portion and the carrier second retaining ring is disposed; A carrier second step portion provided between the carrier second bearing portion and the carrier second large diameter portion,
The crankshaft includes a crankshaft second bearing portion in which the second bearing is disposed, and a crankshaft second small diameter in which the outer diameter is smaller than the crankshaft second bearing portion and the crankshaft second retaining ring is disposed. A crankshaft second step portion provided between the crankshaft second bearing portion and the crankshaft second small diameter portion,
The movement restricting means is disposed across the crankshaft second retaining ring and the crankshaft second step portion and between the carrier second retaining ring and the carrier second step portion. An eccentric oscillating gear device comprising a second ring member. The eccentric oscillating gear device according to claim 1,
The first bearing has a dedicated first outer ring and first inner ring,
The second bearing has a dedicated second outer ring and second inner ring,
The movement restricting means further includes a carrier first groove provided in the first carrier, and a carrier first retaining ring fitted in the carrier first groove,
The crankshaft second retaining ring faces the second inner ring,
The carrier first retaining ring faces the first outer ring;
The eccentric rocking gear device, wherein the second carrier retaining ring faces the second outer ring. In the eccentric rocking | fluctuation type gear apparatus in any one of Claims 1-3,
The first carrier includes a carrier first bearing portion in which the first bearing is disposed, a carrier first large-diameter portion having an inner diameter larger than the carrier first bearing portion, the carrier first bearing portion, and the carrier first A carrier first step portion provided between the first large diameter portion, a carrier first groove provided in the first carrier large diameter portion, and a carrier first retaining ring fitted in the first carrier groove. Have
An eccentric oscillating gear device, wherein a first ring member facing the first bearing is disposed between the carrier first retaining ring and the first carrier step. In the eccentric rocking | fluctuation type gear apparatus in any one of Claims 1-3,
The input gear has a protruding portion protruding toward the first bearing;
The eccentric oscillating gear device is characterized in that the axial movement of the first bearing is restricted by the protrusion. The eccentric oscillating gear device according to claim 3,
The crankshaft includes an eccentric body that swings the swing gear,
An eccentric bearing is disposed between the eccentric body and the swing gear,
At least one of the first inner ring or the first outer ring of the first bearing and the second inner ring or the second outer ring of the second bearing is opposed to the retainer of the eccentric bearing. Gear device.

Images