JP6878036B2 - Eccentric swing type gear device - Google Patents

Description

The present invention relates to an eccentric swing type gear device.

Patent Document 1 discloses an eccentric swing type gear device in which a swinging external gear meshes inscribedly with an internal gear.

This gear device includes a crankshaft that swings the external gear, a first carrier arranged on one side of the external gear in the axial direction, and a second carrier arranged on the other side of the external gear in the axial direction. have. A first bearing is arranged between the first carrier and the crankshaft. A second bearing is arranged between the second carrier and the crankshaft. At the end of the crankshaft on the first carrier side, an input gear for inputting power to the crankshaft is provided.

In this gear device, the axial movement of the crankshaft with respect to the first carrier and the second carrier is carried out by a retaining ring fitted in a groove formed in the crankshaft and a groove formed in the first carrier and the second carrier. It is regulated by a fitted retaining ring.

Japanese Unexamined Patent Publication No. 2014-555654 (Fig. 1)

In this type of gear system, maintaining proper crankshaft strength is one of the important design items. An object of the present invention is to maintain a higher strength of the crankshaft without increasing the outer diameter of the crankshaft.

In the present invention, the oscillating gear, the crank shaft that oscillates the oscillating gear, the first carrier arranged on one side in the axial direction of the oscillating gear, and the other side in the axial direction of the oscillating gear. The second carrier, the first bearing arranged between the first carrier and the crank shaft, the second bearing arranged between the second carrier and the crank shaft, and the crank shaft. In an eccentric swing type gear device including an input gear provided at an end on the first carrier side, the crank shaft includes a second bearing portion of the crank shaft on which the second bearing is arranged. It has an eccentric body that swings the swing gear and a second eccentric body step portion provided between the crank shaft second bearing portion and the eccentric body, and is provided on both sides in the axial direction of the crank shaft. The movement regulating means has a movement regulating means for restricting the movement of the crank shaft, and the movement regulating means is fitted into the second groove of the crank shaft provided at the end of the crank shaft on the second carrier side and the second groove of the crank shaft. The second eccentric body step portion has a second stop ring for the crank shaft, a second carrier groove provided on the second carrier, and a second carrier ring fitted in the second carrier groove. And the crank shaft second stop ring sandwiches the second bearing to restrict the movement of the crank shaft to both sides in the axial direction, and the crank shaft is a crank shaft first bearing portion on which the first bearing is arranged. The crank shaft has a smaller outer diameter than the crank shaft first bearing portion that functions as a component of the movement restricting means between the crank shaft first bearing portion and the input gear. The above problem is solved by adopting a structure having no part.

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

The present invention pays attention to this point. The crankshaft according to the present invention does not have a small diameter portion between the first bearing and the input gear having an outer diameter smaller than the arrangement portion of the first bearing in order to regulate the axial movement. Therefore, 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.

Overall sectional view showing an example of an eccentric swing type gear device according to an embodiment of the present invention. Enlarged sectional view of the main part of FIG. FIG. 2 is a cross-sectional view corresponding to FIG. 2 showing an example of an eccentric swing type gear device according to another embodiment of the present invention. FIG. 2 is a cross-sectional view corresponding to FIG. 2 showing an example of an eccentric swing type gear device according to still another embodiment of the present invention.

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

FIG. 1 is an overall sectional view showing an example of an eccentric swing type gear device G1 according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of a main part of FIG.

The gear device G1 has a first external gear 12A and a second external gear 12B arranged adjacent to the first external gear 12A in the axial direction as swing gears. The first external gear 12A and the second external gear 12B are inscribed in mesh with the internal gear 16. Further, the gear device G1 is arranged 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. It also has a first carrier 30A and a second carrier 30B arranged 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 take out the relative rotations 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. ..

Hereinafter, a more specific description will be given.

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

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

Each crankshaft 20 is provided with an input gear 50 at an end on the first carrier 30A side. The input gear 50 meshes with the drive source side pinion (not shown) arranged at the position of the axial center C16 of the internal gear 16 at the same time. An inner spline 51 for transmitting power from the drive source side to the crankshaft 20 is formed on the inner circumference of the input gear 50.

An outer spline 21 and grooves 78 and 79 that engage the inner spline 51 of the input gear 50 are formed at the end of the crankshaft 20 on the carrier side. The movement of the input gear 50 along the axial direction of the crankshaft 20 is restricted by the 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 composed of 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 axial centers C52A and C52B eccentric with respect to the axial 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 (they are eccentric in the directions away from each other).

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

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

In the gear device G1, the internal gear 16 is rotatably incorporated into the internal gear main body 17 integrated with the casing 62 and the pin groove 18 formed in the internal gear main body 17, and the internal gear 16 is rotatably incorporated into the internal gear 16 It has a columnar pin member 19 that constitutes the internal teeth of the above. The number of teeth of the internal gear 16 (the number of pin members 19) is slightly larger (only 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 arranged between the casing 62 of the gear device G1 and the first carrier 30A. A second main bearing 74B is arranged between the casing 62 and the second carrier 30B. In this gear device G1, the first main bearing 74A and the second main bearing 74B are composed of angular contact ball bearings incorporated in a back-to-back arrangement. 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 composed of a carrier first main rolling surface 37A formed on the first carrier 30A. The inner ring of the second main bearing 74B is composed of a carrier second main rolling surface 37B formed on the second carrier 30B.

From the second carrier 30B, the carrier pin 31 projects 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 30A and the second carrier 30B are connected and integrated by a bolt 76 via a carrier pin 31.

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

Mainly, referring 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 arranged 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 arranged between the first carrier 30A and the crankshaft 20. A second bearing 66B is arranged 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 has a first roller 66A1 as a rolling element and a first retainer 66A2 for holding the first roller 66A1. The first bearing 66A does not have a dedicated inner and outer ring. The crankshaft 20 (crankshaft first bearing portion 25A) also serves as the inner ring of the first bearing 66A, and the first carrier 30A (carrier first bearing portion 35A) also serves as the outer ring of the first bearing 66A.

The second bearing 66B has 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 and outer ring. The crankshaft 20 (crankshaft second bearing portion 25B) also serves as the inner ring of the second bearing 66B, and the second carrier 30B (carrier second bearing portion 35B) also serves as the outer ring of the second bearing 66B.

The first eccentric bearing 56A arranged 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. It has a first eccentric bearing retainer 56A2. The first eccentric bearing 56A also does not have a dedicated inner and outer ring. The first eccentric body 52A also serves as the inner ring of the first eccentric bearing 56A, and the first external gear 12A (crankshaft through hole 12A1) also serves as the outer ring of the first eccentric bearing 56A.

The second eccentric bearing 56B arranged between the second eccentric body 52B and the second external gear 12B also holds the second eccentric bearing roller 56B1 as a rolling element and the second eccentric bearing roller 56B1. It has an eccentric bearing retainer 56B2. The second eccentric bearing 56B also does not have a dedicated inner and outer ring. The second eccentric body 52B also serves as the inner ring of the second eccentric bearing 56B, and the second external gear 12B (crankshaft through hole 12B1) also serves as the outer ring of the second eccentric bearing 56B. In this 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 sliding ring 70A is in contact with the first eccentric body step portion 27A 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 configuration relating to the axial movement regulation of the crankshaft 20 will be described in detail.

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

The first carrier 30A is located on one side in the axial direction (input gear 50 side) of the first external gear 12A, and the carrier first bearing portion 35A on which the first bearing 66A is arranged is the shaft of the first carrier 30A. It is provided on the 12A side of the first external gear in the direction. The second carrier 30B is located on the other side (anti-input gear side) in the axial direction of the second external gear 12B, and the carrier second bearing portion 35B on which the second bearing 66B is arranged is the shaft of the second carrier 30B. It is provided on the 12B side of the second external gear in the direction.

Here, the carrier first bearing portion indicates a portion where the outer ring of the first bearing faces the first carrier. When the first bearing 66A is such as the main gear device G1 having no outer ring, the carrier first bearing portion 35A is the first roller 66A1 which is a rolling element of the first bearing 66A when viewed from the radial direction. Refers to the part projected on the carrier 30A side. 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 a main gear device G1 having no outer ring, the carrier second bearing portion 35B has a second roller 66B1 which is a rolling element of the second bearing 66B when viewed from the radial direction. Refers to the part projected on the carrier 30B side.

On the other hand, the crankshaft 20 has a crankshaft first bearing portion 25A in which the first bearing 66A is arranged 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 arranged 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 a main gear device G1 having no inner ring, the crankshaft first bearing portion 25A cranks the first roller 66A1 which is a rolling element of the first bearing 66A when viewed from the radial direction. Refers to the part projected on the axis 20 side. 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 a main gear device G1 having no inner ring, the crankshaft second bearing portion 25B cranks the second roller 66B1 which is a rolling element of the second bearing 66B when viewed from the radial direction. Refers to the part projected on the axis 20 side.

The movement regulating means for the crankshaft 20 of the gear device G1 is 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. Further, the movement regulating means are a carrier second groove 33B provided in the second carrier 30B (the 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 has the carrier second bearing portion 35B in which the second bearing 66B is arranged, and the carrier second large diameter portion 38B in which the carrier second retaining ring 34B is arranged. The carrier second groove 33B is formed in the carrier second large diameter portion 38B.

The inner diameter (radius: the same applies hereinafter) 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 stage portion 36B having a 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 has a crankshaft second bearing portion 25B in which the second bearing 66B is arranged, and a crankshaft second small diameter portion 28B in which the crankshaft second retaining ring 24B is arranged. The crankshaft second groove 23B is formed in the crankshaft second small diameter portion 28B.

The outer diameter (radius: the same applies hereinafter) 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 stage 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.

Then, the second ring member 73B straddles between the crankshaft second retaining ring 24B and the crankshaft second stage portion 26B, and between the carrier second retaining ring 34B and the carrier second stage portion 36B. Have been placed.

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

On the other hand, on the first carrier 30A side of the crankshaft 20, as described above, only 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. The movement regulation of the crankshaft 20 in the axial direction is completed on the second carrier 30B side of the crankshaft 20 in both directions on both sides in the axial direction. At the position on the input gear 50 side of the crankshaft first bearing 25A (between the crankshaft first bearing 25A and the input gear 50), any component that functions as a component of the movement restricting means is provided. Absent.

In other words, the purpose of restricting the axial movement of the crankshaft 20 at the position on the input gear 50 side of the crankshaft first bearing 25A (between the crankshaft first bearing 25A and the input gear 50). Therefore, there is no small diameter portion formed having an outer diameter smaller than that of the crankshaft first bearing portion 25A.

The first carrier 30A is provided on the carrier first bearing portion 35A in which the first bearing 66A is arranged and on the axial input gear 50 side of the carrier first bearing portion 35A, and is provided on the inner diameter of the carrier first bearing portion 35A. It has a carrier first large diameter portion 38A having an inner diameter R38A larger than that of R35A by a diameter difference δ (35A-38A). A carrier first stage portion 36A having a diameter difference δ (35A-38A) is formed between the carrier first bearing portion 35A and the carrier first large diameter portion 38A. 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 facing the first bearing 66A is arranged between the carrier first retaining ring 34A and the carrier first stage portion 36A. The first ring member 73A faces the first bearing 66A (the first retainer 66A2) and regulates the axial movement of the first bearing 66A.

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

When the 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 meshing at the same time as the drive source side pinion rotate at the same rotation 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 in the same direction at the same rotation speed.

As a result, the first external gear 12A swings and rotates via the first eccentric body 52A whose phases are aligned on each crankshaft 20. Further, the second external gear 12B swings and rotates via 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 inscribed in 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 one more than the number of teeth of the second external gear 12B. Therefore, the first external gear 12A and the second external gear 12B are used once for each rotation of the crankshaft 20 (for each rotation of the first eccentric body 52A and the second eccentric body 52B). It swings and is out of phase with respect to the internal gear 16 by the difference in the number of teeth (one tooth in this gear device G1).

As a result, the crankshaft 20 penetrating the first external gear 12A and the second external gear 12B revolves around the axis C16 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 on the crankshaft second stop ring 24B and the second carrier 30B, which are fitted in the crankshaft second groove 23B provided at the end of the crankshaft 20 on the second carrier 30B side. The second stage portion 36B of the carrier regulates the movement of the crankshaft 20 toward the first carrier 30A in the axial direction via the second ring member 73B.

Further, the crankshaft 20 is provided with a second carrier in the axial direction via a second ring member 73B by a second stage portion 26B of the crankshaft of the crankshaft 20 and a 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 restricting of the crankshaft 20 to both sides in the axial direction only by the movement regulating means provided on the axially opposite first carrier side of the second bearing 66B. ..

Various loads are constantly applied to the crankshaft 20 of this type of gear device G1 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. In particular, the position on the input gear 50 side of 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 for rotating the crankshaft 20. A 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 side. Further, since the input gear 50 is provided at a portion protruding from the first bearing 66A in a cantilevered state, bending stress and shear stress due to torque transmission and eccentric swing are also compared with other positions of the crankshaft 20. It tends to occur larger. Therefore, the position on the input gear 50 side of the crankshaft first bearing portion 25A is in a more severe state in terms of strength than the other positions of the crankshaft 20.

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

Further, in the main gear device G1, from the viewpoint of "regulating the axial movement of the first bearing 66A", the position of the crankshaft 20 on the input gear 50 side of the crankshaft first bearing portion 25A (crankshaft first). No small diameter portion having an outer diameter smaller than that of the first crankshaft bearing portion 25A is formed between the bearing portion 25A and the input gear 50). That is, in the main gear device G1, the strength does not decrease at the position on the input gear 50 side of the crankshaft first bearing portion 25A from the viewpoint of positioning the first bearing 66A in the axial direction.

Regarding the configuration of "regulating the axial movement of the first bearing 66A", for example, a modified example as shown in FIG. 3 may be adopted. In the gear device G2 shown in FIG. 3, the input gear 150 has a protruding portion 151 protruding toward the first bearing 66A. The protrusion 151 faces the first retainer 66A2 of the first bearing 66A via the washer 154, and regulates the axial movement of the first bearing 66A. The input gear 150 is fixed to the end of the crankshaft 120 by a bolt 153. The other configurations are the same as those of the gear device G1 (in FIG. 3, the parts corresponding to those in FIG. 2 are designated by the same reference numerals).

Even with such a configuration, the crankshaft of the crankshaft 120 is located 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 regulated without forming any small diameter portion having an outer diameter 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 the position on the input gear side of the crankshaft first bearing portion (between the crankshaft first bearing portion 25A and the input gear 150). The configuration that realizes that "there is no small diameter portion having a small outer diameter" is not limited to the configurations of the gear devices G1 and G2.

For example, in the gear device G1 of FIGS. 1 and 2, the carrier first stage 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 the carrier first groove 33A provided in the carrier first large diameter portion 38A. The first ring member 73A faces the first retainer 66A2 of the first bearing 66A and is arranged between the carrier first retaining ring 34A and the carrier first stage portion 36A. Further, the first sliding 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 carrier first stage portion 36A, a carrier first 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 to the first carrier 30A side (input gear 50 side) in the axial direction is also restricted by.

Therefore, in the gear device G1 of FIGS. 1 and 2, for example, the carrier second stage portion 36B may not be provided. That is, the carrier second groove 33B and the carrier second retaining ring 34B are provided on the surface having the same inner diameter as the carrier second bearing portion 35B, and the second ring member 73B is the second retainer 66B2 and the crankshaft of the second bearing 66B. It may be configured to face the second stage portion 26B.

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

Further, in order to realize the movement restriction of the crankshaft 20 on both sides in the axial direction, the configuration of the gear device G3 as shown in FIG. 4 can be adopted.

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

The first bearing 266A having the dedicated first outer ring 266A3 and the first inner ring 266A4 is restricted from moving in the axial direction of the first outer ring 266A3 and the first inner ring 266A4 by itself. The second bearing 266B having the dedicated second outer ring 266B3 and the second inner ring 266B4 is also restricted from moving in the axial direction of the second outer ring 266B3 and the second inner ring 266B4 by itself.

The movement regulating means for restricting the movement of the crankshaft 220 to both sides in the axial direction is premised on having such a first bearing 266A and a second bearing 266B, and the crankshaft first fitted in the crankshaft second groove 223B. In addition to the 2 retaining ring 224B and the carrier 2nd retaining ring 234B fitted in the carrier 2nd groove 233B, the carrier 1st groove 233A provided in the 1st carrier 230A and the carrier 1st groove 233A were fitted. It has a carrier first retaining ring 234A.

Then, the crankshaft second retaining ring 224B faces the second inner ring 266B4 of the second bearing 266B, the carrier second retaining ring 234B faces the second outer ring 266B3 of the second bearing 266B, and the carrier first retaining ring The 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 faces the first eccentric bearing retainer 256A2 of the first eccentric bearing 256A. The first inner ring 266A4 of the first bearing 266A faces the 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 faces the second eccentric body step portion 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 sandwich the central ring member 272 in the center in the axial direction, and the first eccentric bearing retainer 256A2 and the second eccentric of the first eccentric bearing 256A. The second eccentric bearing retainer 256B2 of the bearing 256B is sandwiched.

On the other hand, in this 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 a surface having the same inner diameter as the carrier second bearing portion 235B.

Also in this gear device G3, the axial movement of the crankshaft 220 is restricted at the position on the input gear 250 side of 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 formed with an outer diameter smaller than that of the crankshaft first bearing portion 225A.

Further, in this gear device G3, since neither the first carrier 230A nor the second carrier 230B is provided with the carrier first stage portion or the carrier second stage portion, 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 (or the second main) of the first main bearing 274A. The hardness is maintained high so that it can function as the carrier second main rolling surface 237B) of the bearing 274B. Therefore, for example, in the case of the configuration as shown in the gear device G1 of 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. It is necessary to form the carrier first bearing portion 35A or the carrier second bearing portion 35B (which functions as a rolling surface), and it takes time, effort, and cost to process the first carrier 30A and the second carrier 30B.

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

Further, in this gear device G3, the first outer ring 266A3 of the first bearing 266A faces 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 eccentricity. The first eccentric bearing retainer 256B2 of the bearing 256B faces the first inner ring 266A4 of the first bearing 266A and the second inner ring 266B4 of the second bearing 266B faces the first eccentric bearing retainer 256A2 and the second eccentric bearing retainer 256B2. It may be configured to do so).

As a result, the movement of the crankshaft 220 to both sides in the axial direction can be more reliably regulated. Since the other configurations and operations are the same as those of the gear device G1 described above, only the last two digits have the same reference numerals to the main parts corresponding to those in FIG. 2 in FIG. 4, and duplicate description will be omitted.

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

Further, in the above embodiment, the external tooth swing type eccentric swing type gear device in which the first external tooth gear and the second external tooth gear swing with respect to the internal tooth gear (in a fixed state). Was shown. However, among the eccentric swing type gear devices, there is also known an internal tooth swing type eccentric swing type gear device in which the internal gear swings with respect to the external gear by the crankshaft.

The present invention is any type of eccentric swing type gear device provided with an input gear that transmits power to the crankshaft at the end of the crankshaft that swings the swing gear on the first carrier side. It can also be applied to the eccentric swing type gear device, and the same effect can be obtained.

G1 ... Gear device 12A ... First external gear (oscillating gear)
12B ... 2nd external gear (swing gear)
20 ... Crankshaft 30A ... 1st carrier 30B ... 2nd carrier 66A ... 1st bearing 66B ... 2nd bearing 50 ... Input gear 23B ... Crankshaft 2nd groove 24B ... Crankshaft 2nd retaining ring 33B ... Carrier 2nd groove 34B ... Carrier 2nd retaining ring 25A ... Crankshaft 1st bearing 25B ... Crankshaft 2nd bearing

Claims (6)

The oscillating gear, the crankshaft that oscillates the oscillating gear, the first carrier arranged on one side of the oscillating gear in the axial direction, and the second carrier arranged on the other side of the oscillating gear in the axial direction. A carrier, a first bearing arranged between the first carrier and the crankshaft, a second bearing arranged between the second carrier and the crankshaft, and the first bearing of the crankshaft. In an eccentric swing type gear device provided with an input gear provided at an end on the carrier side,
The crankshaft is provided between a crankshaft second bearing portion in which the second bearing is arranged, an eccentric body that swings the swing gear, and the crankshaft second bearing portion and the eccentric body. It has a second eccentric body step and
It has a movement regulating means for restricting the movement of the crankshaft to both sides in the axial direction.
The movement restricting means includes a crankshaft second groove provided at the end of the crankshaft on the second carrier side, a crankshaft second retaining ring fitted in the crankshaft second groove, and the second. It has a carrier second groove provided on the carrier and a carrier second retaining ring fitted in the carrier second groove, and the second eccentric body step portion and the crankshaft second retaining ring are the second retaining ring. By sandwiching the bearing, the movement of the crankshaft to both sides in the axial direction is restricted.
The crankshaft has a crankshaft first bearing portion on which the first bearing is arranged, and the crankshaft is a movement regulating means between the crankshaft first bearing portion and the input gear. An eccentric swing type gear device characterized in that it does not have a small diameter portion having an outer diameter smaller than that of the first bearing portion of the crankshaft that functions as a component. The oscillating gear, the crankshaft that oscillates the oscillating gear, the first carrier arranged on one side of the oscillating gear in the axial direction, and the second carrier arranged on the other side of the oscillating gear in the axial direction. A carrier, a first bearing arranged between the first carrier and the crankshaft, a second bearing arranged between the second carrier and the crankshaft, and the first bearing of the crankshaft. In an eccentric swing type gear device provided with an input gear provided at an end on the carrier side,
It has a movement regulating means for restricting the movement of the crankshaft to both sides in the axial direction.
The movement restricting means includes a crankshaft second groove provided at the end of the crankshaft on the second carrier side, a crankshaft second retaining ring fitted in the crankshaft second groove, and the second. It has a carrier second groove provided on 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 arranged, and the crankshaft has a crankshaft first bearing portion.
The crankshaft has a small diameter portion between the crankshaft first bearing portion and the input gear, which has an outer diameter smaller than that of the crankshaft first bearing portion that functions as a component of the movement restricting means. No,
The second carrier includes a carrier second bearing portion in which the second bearing is arranged, a carrier second large diameter portion in which the inner diameter is larger than that of the carrier second bearing portion, and the carrier second retaining ring is arranged. It has a carrier second stage portion provided between the carrier second bearing portion and the carrier second large diameter portion.
The crankshaft has a crankshaft second bearing portion on which the second bearing is arranged and a crankshaft second small diameter on which the crankshaft second stop ring is arranged, which is smaller in outer diameter than the crankshaft second bearing portion. It has a portion and a crankshaft second stage portion provided between the crankshaft second bearing portion and the crankshaft second small diameter portion.
The movement restricting means is arranged so as to straddle between the crankshaft second retaining ring and the crankshaft second stage portion, and between the carrier second retaining ring and the carrier second stage portion. An eccentric swing type gear device characterized by having a second ring member. In the eccentric swing type gear device according to claim 1,
The first bearing has a dedicated first outer ring and a first inner ring.
The second bearing has a dedicated second outer ring and a second inner ring.
The movement regulating 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,
An eccentric swing type gear device, wherein the carrier second retaining ring faces the second outer ring. The oscillating gear, the crankshaft that oscillates the oscillating gear, the first carrier arranged on one side of the oscillating gear in the axial direction, and the second carrier arranged on the other side of the oscillating gear in the axial direction. A carrier, a first bearing arranged between the first carrier and the crankshaft, a second bearing arranged between the second carrier and the crankshaft, and the first bearing of the crankshaft. In an eccentric swing type gear device provided with an input gear provided at an end on the carrier side,
It has a movement regulating means for restricting the movement of the crankshaft to both sides in the axial direction.
The movement restricting means includes a crankshaft second groove provided at the end of the crankshaft on the second carrier side, a crankshaft second retaining ring fitted in the crankshaft second groove, and the second. It has a carrier second groove provided on 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 arranged, and the crankshaft has a crankshaft first bearing portion.
The crankshaft has a small diameter portion between the crankshaft first bearing portion and the input gear, which has an outer diameter smaller than that of the crankshaft first bearing portion that functions as a component of the movement restricting means. No,
The first carrier includes a carrier first bearing portion in which the first bearing is arranged, a carrier first large diameter portion having an inner diameter larger than that of the carrier first bearing portion, the carrier first bearing portion, and the carrier first bearing portion. A carrier first stage portion provided between the large diameter portion, a carrier first groove provided in the carrier first large diameter portion, and a carrier first retaining ring fitted in the carrier first groove. Have,
An eccentric swing type gear device, characterized in that a first ring member facing the first bearing is arranged between the carrier first retaining ring and the carrier first step portion. In the eccentric swing type gear device according to any one of claims 1 to 3.
The input gear has a protrusion that protrudes toward the first bearing side.
An eccentric swing type gear device, characterized in that the axial movement of the first bearing is restricted by the protrusion. In the eccentric swing type gear device according to claim 3,
The crankshaft includes an eccentric body that swings the swing gear.
An eccentric bearing is arranged between the eccentric body and the oscillating gear.
An eccentric swing type, characterized in that 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 faces the retainer of the eccentric bearing. Gear device.

Images