JP2013185650A - Eccentric swing gear device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an eccentric swing gear device capable of reducing lead time required for production.SOLUTION: An eccentric swing gear device 10 includes a crank shaft 46, swing gears 48a, 48b, a case 12, and a carrier 14. The carrier 14 supports the crank shaft 46 rotatably. The case 12 has internal teeth 24 meshed with tooth parts of the swing gears 48a, 48b. The case 12 and the carrier 14 concentrically rotate relative to each other when the swing gears 48a, 48b swing along with rotation of the crank shaft 46. The case 12 is configured to separately form a mounted part 21 having portions for fixing bolts to be mounted on a first arm, and an adjacent part 22 which is adjacent to the mounted part 39 and including the internal teeth 24. The mounted part 21 is assembled to the adjacent part 22.

Description

  The present invention relates to an eccentric oscillating gear device.

  Conventionally, as disclosed in Patent Document 1 below, an eccentric oscillating gear device that can be used in a joint portion of an industrial robot or the like is known. The eccentric oscillating gear device disclosed in Patent Document 1 includes a case having internal teeth, a carrier inserted into the case and rotatable with respect to the case, an eccentric portion, and rotatable on the carrier. And a swing gear that is fitted to the eccentric portion and swings while meshing with the internal teeth of the case. When the crankshaft is driven by the motor and rotates about the axis, the swing gear swings, and accordingly, the carrier rotates relative to the case. And since the case is fixed to the proximal arm of the industrial robot by bolts and the carrier is fixed to the distal arm by bolts, when the motor is driven, the rotation speed is reduced at a predetermined ratio. The distal arm can be rotated relative to the proximal arm.

JP 2006-31957 A

  The eccentric oscillating gear device disclosed in Patent Document 1 has a problem that the lead time during manufacture is long. That is, the case is formed in a cylindrical shape as a whole, but a large number of internal teeth grooves are formed on the inner surface so as to dispose a large number of inner teeth, while the outer surface is a tip that is a mating member to which the case is attached. A flange having a bolt hole for fastening to the side arm is provided, and the structure is complicated. The case is a cast product or a forged product, and a bolt hole is formed by machining. The position and size of the bolt hole to be attached to the member on the other side, or the shape of the flange portion varies depending on the specifications at the customer to whom the eccentric oscillating gear device is delivered, and varies greatly. For this reason, it is practically difficult to make a case in advance in anticipation of an order. Moreover, the configuration of the case is complicated. Therefore, there is a problem that the lead time from when the order is confirmed until delivery can be extended.

  Accordingly, the present invention has been made in view of the above prior art, and an object of the present invention is to provide an eccentric oscillating gear device that can reduce the lead time required for production.

  In order to achieve the above object, the present invention provides a gear device for generating a relative rotation at a rotational speed reduced with respect to an input rotational speed between a first member and a second member. The crankshaft having the eccentric portion, the swinging gear having the through hole into which the eccentric portion is inserted and having the tooth portion, and being attachable to one of the first member and the second member. And a carrier configured to be attachable to the other of the first member and the second member, the carrier rotatably supporting the crankshaft, and the case The case and the carrier are concentrically rotatable relative to each other by the swing of the swing gear accompanying the rotation of the crankshaft. And the case has the first A mounted portion having a portion for fixing a fastener attached to the one of the material and the second member, and a portion adjacent to the mounted portion, where the internal teeth are disposed The eccentric oscillating gear device having a configuration in which the adjacent portion is formed separately and the mounted portion is assembled to the adjacent portion.

  In the present invention, the case is divided into a mounted portion which is a portion attached to the one of the first member and the second member, and an adjacent portion which is a portion adjacent to the mounted portion. Formed in the body. For this reason, the adjacent part, which is the part where the internal teeth are arranged, is configured as a common structure that is not affected by the customer's specifications, and only the structure of the mounted part is changed according to the customer's specifications. can do. For this reason, the adjacent portion in the case does not depend on the customer's specifications, and therefore it is possible to perform prospective production before the order is confirmed. Then, the attached portion is manufactured at the time when the order is confirmed, and the case is manufactured by assembling with other parts. Therefore, since it is sufficient to produce only the attached portion after the order is confirmed, the lead time required for production can be shortened as compared with the conventional configuration.

  In the eccentric oscillating gear device, the attached portion may be positioned by fitting into the adjacent portion. In this aspect, it can position with respect to an adjacent part only by fitting a to-be-attached part to an adjacent part.

  The attached portion may be formed with an insertion hole through which a fastener can be inserted, and the adjacent portion may be formed with a fastening hole to which the fastener is fastened. The part and the adjacent part are preferably fastened to each other by the fastener. In this aspect, since the attached portion is assembled to the adjacent portion by the fastener, the attached portion can be more firmly assembled to the adjacent portion.

  The fastening hole may communicate with an internal tooth groove in which the internal teeth are disposed. In this aspect, the insertion hole and the fastening hole can be used as a supply / discharge oil hole for supplying or discharging oil to / from the internal tooth groove.

  As described above, according to the present invention, an eccentric oscillating gear device that can reduce the lead time required for production can be provided.

It is sectional drawing which shows the structure of the eccentric rocking | fluctuation type gear apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention. It is sectional drawing which shows the structure of the case used for the eccentric rocking | fluctuation type gear apparatus which concerns on other embodiment of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, the eccentric oscillating gear device 10 according to the present embodiment is input with a case 12 and a carrier 14 that can rotate relative to the case 12 inside the case 12. And a speed reduction mechanism 18 for decelerating the rotational speed at a predetermined rotational speed ratio. In the gear device 10, a first arm (not shown), which is a first member (mating member), is fastened to the case 12, and a second member (mating member), which is not shown, is connected to the carrier 14. Two arms are fastened. That is, the first arm and the second arm constitute a robot arm, and the eccentric oscillating gear device 10 is constituted as a speed reducer used for a joint of the robot arm.

  The case 12 has a case main body 12a formed in a cylindrical shape, and a flange portion 12b provided outside the case main body 12a. The flange portion 12b is shorter in the axial direction than the case main body 12a, and has a shape projecting outward from the axial central portion of the case main body 12a. The flange portion 12b may have a shape protruding outward from the axial end portion of the case main body 12a.

  A large number of pin grooves (internal tooth grooves) 12d are formed at equal intervals in the circumferential direction on the inner peripheral surface of the case body 12a, and pin-shaped inner teeth 24 are fitted into the pin grooves 12d, respectively. .

  In the present embodiment, the case main body 12a and the flange portion 12b are formed separately and then coupled to each other. That is, the flange part 12b is comprised as the to-be-attached part 21 which has a site | part for fixing the volt | bolt (illustration omitted) as a fastener attached to a 1st arm. On the other hand, the case main body 12a is configured as an adjacent portion 22 which is a portion adjacent to the attached portion 21 and where the internal teeth 24 are disposed. And the to-be-attached part 21 and the adjacent part 22 are formed in the different body. For example, the attached portion 21 and the adjacent portion 22 are surfaced by being cast or forged and then machined.

  The adjacent portion 22 is formed in a cylindrical shape, and the attached portion 21 is externally fitted to the adjacent portion 22. In other words, the inner diameter of the attached portion 21 has a size corresponding to the outer diameter of the adjacent portion 22, so that the attached portion 21 can be fitted onto the adjacent portion 22. The fitting of the attached portion 21 to the adjacent portion 22 may be a fitting by press fitting, shrink fitting, plastic bonding, or the like. Moreover, it is good also considering the coupling | bonding of the adjacent part 22 and the to-be-attached part 21 as a spline coupling | bonding.

  A plurality of pin grooves 12d are formed at equal intervals in the circumferential direction on the inner peripheral surface of the case body 12a constituting the adjacent portion 22, and pin-shaped inner teeth 24 are fitted into the pin grooves 12d, respectively. Yes. That is, a large number of internal teeth 24 are disposed in the adjacent portion 22.

  Bolt insertion holes 12c are provided in the flange portion 12b constituting the attached portion 21 at equal intervals in the circumferential direction. The case 12 and the first arm are fastened to each other by screwing a bolt (not shown) inserted through the bolt insertion hole 12c into the screw hole of the first arm (not shown). A motor (not shown) that is a drive source is fixed to the first arm.

  A bolt insertion hole 21a that penetrates in the radial direction is formed in the attached portion 21, and a fastening hole 22a is formed in the adjacent portion 22 at a position corresponding to the bolt insertion hole 21a. A plurality of these bolt insertion holes 21 a and fastening holes 22 a are provided in the circumferential direction of the case 12. And the to-be-attached part 21 is in the state fixed to the adjacent part 22 by screwing the volt | bolt 23 inserted in the bolt insertion hole 21a of the to-be-attached part 21 to the fastening hole 22a of the adjacent part 22. FIG.

  The fastening hole 22a passes through the adjacent portion 22 (case body 12a) and communicates with the pin groove 12d. For this reason, it is possible to supply or drain oil into the pin groove 12d through the bolt insertion hole 21a and the fastening hole 22a.

  The bolt insertion hole 21a is formed at a position shifted from the axial center position in the attached portion 21 (flange portion 12b). Therefore, as shown in FIGS. 2 and 3, the position of the flange portion 12b relative to the case main body 12a can be changed by changing the orientation of the attached portion 21. For this reason, it is possible to easily cope with the case where the position of the flange portion 12b needs to be changed by the counterpart member to which the eccentric oscillating gear device 10 according to the present embodiment is attached.

  Note that the length of the attached portion 21 can be appropriately changed depending on the counterpart member and customer specifications. For example, as shown in FIG. 4, the attached portion 21 may be formed so that the axial length thereof is the same as the axial length of the adjacent portion 22 (case body 12 a). In this case, as shown in FIG. 4, the position of the bolt insertion hole 21a in the axial direction may be shifted from the central position in the axial direction, or may be the central position in the axial direction. Further, a plurality of bolt insertion holes 21a may be provided in the axial direction.

  Moreover, in this embodiment, the to-be-attached part 21 is fixed to the adjacent part 22 by screwing the volt | bolt 23 inserted in the bolt insertion hole 21a of the to-be-attached part 21 to the fastening hole 22a of the adjacent part 22. However, it is not limited to this. For example, a pin hole is formed in the attached portion 21 instead of the bolt insertion hole 21a, and a pin is driven into the hole of the adjacent portion 22 formed at a position corresponding to the pin hole, thereby adjoining the attached portion 21. It is good also as a structure fixed to the part 22. FIG.

  The carrier 14 is supported on the case 12 by a pair of main bearings 26 arranged at intervals in the axial direction, and can rotate concentrically with the case 12. That is, the carrier 14 rotates relative to the case 12 around the axis of the case 12. The main bearings 26 are each constituted by an angular ball bearing.

  The carrier 14 includes a disc-shaped end plate portion 30 and a base portion 31 fastened to the end plate portion 30. The base portion 31 includes a substrate portion 32 and a shaft portion 33 projecting from one surface of the substrate portion 32.

  A plurality of shaft portions 33 are provided, and these shaft portions 33 are arranged at equal intervals in the circumferential direction. The shaft portion 33 and the end plate portion 30 are fastened to each other by a bolt 34 in a state where the tip surface of the shaft portion 33 is in contact with the end plate portion 30. In this state, a space having a predetermined width in the axial direction is formed between the base portion 31 and the end plate portion 30.

  A bolt fastening hole 33 a is provided in the shaft portion 33, and the bolt 34 inserted into the bolt insertion hole 30 a of the end plate portion 30 from the opposite side to the shaft portion 33 is screwed into the bolt fastening hole 33 a of the shaft portion 33. Has been. A pin 36 for positioning the end plate portion 30 with respect to the base portion 31 is disposed so as to straddle the shaft portion 33 and the end plate portion 30. That is, the pin 36 is inserted into the insertion hole 30 b formed in the end plate portion 30 and is inserted into the pin hole 33 b formed in the distal end surface of the shaft portion 33.

  A second arm that is a counterpart member is attached to the base 31. That is, a bolt insertion hole is formed in the second arm, and a fastening hole 31 a is formed on the outer surface of the base portion 31 at a position corresponding to the bolt insertion hole. And the 2nd arm and the base 31 are mutually fastened by screwing the unillustrated mounting bolt inserted in the bolt insertion hole of the 2nd arm to the fastening hole 31a of the base 31.

  The substrate portion 32 is formed with a central through hole 32a penetrating the central portion in the radial direction of the base portion in the thickness direction. The substrate portion 32 is provided with a hole portion 32b so that one end portion of a crankshaft 46 described later is inserted and the second crank bearing 52 is attached. A plurality of the holes 32b are provided around the central through hole 32a.

  The end plate portion 30 is formed with a through hole 30c penetrating the center in the axial direction. The through hole 30 c of the end plate portion 30 has substantially the same inner diameter as the central through hole 32 a of the substrate portion 32.

  The speed reduction mechanism 18 includes a transmission gear 44, a crankshaft 46, and a swing gear (a first swing gear 48a and a second swing gear 48b). The first oscillating gear 48 a and the second oscillating gear 48 b each have external teeth that are teeth that mesh with the internal teeth 24 of the case 12. The transmission gear 44 is splined to the end of the crankshaft 46 on the end plate portion 30 side. The transmission gear 44 meshes with a driving gear (not shown) provided on an input shaft (not shown) for inputting a driving force for rotating the carrier 14 (a driving force using a motor (not shown) as a driving source). Accordingly, the driving force is transmitted to the crankshaft 46 via the transmission gear 44, whereby the crankshaft 46 is interlocked with the rotation of the input shaft. Note that the input shaft may be arranged such that the distal end portion is inserted into the through hole 30 c of the end plate portion 30.

  The crankshaft 46 is disposed in parallel with the input shaft, is rotatably supported by the end plate portion 30 via the first crank bearing 51, and is freely rotatable on the substrate portion 32 via the second crank bearing 52. It is supported by. In other words, the first crank bearing 51 is disposed between the end plate portion 30 and the crank shaft 46, and the second crank bearing 52 is disposed between the substrate portion 32 and the crank shaft 46. Both the first crank bearing 51 and the second crank bearing 52 are constituted by tapered roller bearings.

  A plurality of through holes 30d are formed in the end plate portion 30 around the central through hole 30c. These through holes 30d are arranged at equal intervals in the circumferential direction around the central through hole 30c. A plurality of crankshafts 46 are also provided and arranged at equal intervals in the circumferential direction. Each crankshaft 46 passes through the through hole 30 d of the end plate portion 30 and is inserted into the hole portion 32 b of the substrate portion 32.

  The crankshaft 46 includes a shaft main body 46c and eccentric portions (first eccentric portion 46a and second eccentric portion 46b) formed integrally with the shaft main body 46c. The shaft body 46c has a circular cross section, and the eccentric portions 46a and 46b are eccentric with respect to the crankshaft center that is the shaft center of the shaft body 46c. The first and second eccentric parts 46a and 46b are out of phase with each other. That is, the eccentric direction of the first eccentric portion 46a with respect to the crank shaft center and the eccentric direction of the second eccentric portion 46b with respect to the crank shaft center are different from each other, and the phase angle is shifted by 180 degrees. Further, the plurality of crankshafts 46 are assembled so that the eccentric directions of the respective first eccentric portions 46a coincide.

  The first and second eccentric portions 46 a and 46 b are disposed adjacent to each other in the axial direction between the first crank bearing 51 and the second crank bearing 52. The first eccentric portion 46 a is adjacent to the first crank bearing 51, and the second eccentric portion 46 b is adjacent to the second crank bearing 52.

  Both the first oscillating gear 48 a and the second oscillating gear 48 b are disposed in the space between the substrate portion 32 and the end plate portion 30 of the carrier 14. The first oscillating gear 48 a and the second oscillating gear 48 b are respectively provided with a first through hole 48 c formed at the center, a second through hole 48 d through which the shaft portion 33 can pass, and the eccentricity of the crankshaft 46. A third through hole 48e through which the portions 46a and 46b can penetrate is formed.

  Roller bearings 55 are attached to the first and second eccentric portions 46a and 46b. In this state, the first eccentric portion 46a is inserted into the third through hole 48e of the first swing gear 48a, and the second eccentric portion. 46b is inserted through the third through hole 48e of the second swing gear 48b. The first and second swing gears 48 a and 48 b rotate while meshing with the internal teeth 24 of the case 12 as the first and second eccentric portions 46 b swing due to the rotation of the crankshaft 46. In the present embodiment, two swing gears 48a and 48b are provided. However, the present invention is not limited to this configuration, and one or three or more swing gears 48a and 48b may be provided. Good.

  In the eccentric oscillating gear device 10 according to the present embodiment, the input shaft is driven by the driving force of the motor, and when the input shaft rotates, the transmission gear 44 rotates. As a result, the crankshaft 46 also rotates integrally, and when the crankshaft 46 rotates, the first oscillating gear 48a rotates while meshing with the internal teeth 24 as the first eccentric portion 46a oscillates. As the portion 46 b swings, the second swing gear 48 b rotates while meshing with the internal teeth 24. As a result, the carrier 14 having the shaft portion 33 penetrating the second through hole 48d of both the oscillating gears 48a and 48b rotates relative to the case 12. As a result, the second arm rotates relative to the first arm. The rotational speed of the second arm (carrier 14) is a rotational speed that is decelerated at a predetermined ratio with respect to the rotational speed of the input shaft. That is, the speed reduction mechanism 18 rotates the carrier 14 relative to the case 12 at a rotational speed that is reduced at a predetermined ratio with respect to the rotational speed of the input shaft.

  The attached portion 21 is selectively used according to the shape of the mating member to which the gear device 10 is attached. In FIG. 1, the attached portion 21 is fixed to the second arm of the robot arm. However, the attached portion 21 may be attached to a member having a different configuration. And only the attached portion 21 can be selectively used according to the mating member among the components constituting the case 12, while the other components are the same components regardless of the mating member. Can be used.

  In addition, you may perform the operation | work which attaches the to-be-attached part 21 to the adjacent part 22 before assembling this gear apparatus 10 (In this case, it will assemble | attach to the carrier 14 as the case 12 to which the to-be-attached part 21 was attached). Alternatively, the above operation may be performed while the gear device 10 is being assembled, or after the gear device 10 is assembled with parts other than the attached portion 21 and the installation specifications at the customer are determined, That is, the operation may be performed at a timing before shipping. The operation may be performed at any timing.

  As described above, in the present embodiment, the case 12 includes the attached portion 21 (flange portion 12b) that is a portion on the side attached to the first arm and the adjacent portion 22 that is a portion adjacent to the attached portion 21. (Case body 12a) and a separate body. For this reason, about the adjacent part 22, it can be set as the common structure which is not influenced by a customer's specification, and it can be set as the structure which changes only the to-be-attached part 21 according to a customer's specification. For this reason, the adjacent portion 22 in the case 12 does not depend on the customer's specifications, and therefore it is possible to perform prospective production before the order is confirmed. Then, the attached portion 21 may be manufactured at the time when the order is confirmed, and the case 12 may be manufactured by assembling with other parts. Therefore, since it is sufficient to produce only the attached portion 21 after the order is confirmed, the lead time required for production can be shortened as compared with the conventional configuration.

  Moreover, in this embodiment, since the to-be-attached part 21 and the adjacent part 22 are mutually fastened by the volt | bolt 23, the to-be-attached part 21 can be assembled | attached to the adjacent part 22 more firmly.

  In addition, in the present embodiment, the fastening holes 22a of the adjacent portions 22 communicate with the pin grooves 12d in which the inner teeth 24 are disposed, so that the bolt insertion holes 21a and the fastening holes 22a are supplied to or drained from the pin grooves 12d. Therefore, it can be used as a supply / discharge oil hole.

  Note that the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made without departing from the spirit of the present invention. For example, in the embodiment, the case main body 12a (adjacent portion 22) and the flange portion 12b (attached portion 21) are fixed by the bolt 23. However, as shown in FIGS. Fixing by may be omitted. In this configuration, since the attached portion 21 is positioned by fitting into the adjacent portion 22, the attached portion 21 can be positioned with respect to the adjacent portion 22 simply by fitting the attached portion 21 into the adjacent portion 22. . In this case, the flange portion 12b may be fixed to the case main body 12a by shrink fitting, or the case main body 12a may be press-fitted into the flange portion 12b. In the case 12 shown in FIGS. 5 and 6, the axial length of the flange portion 12b is common in that the axial length of the case main body 12a is shorter than the case main body 12a. Arrangement position is different. On the other hand, in the case 12 shown in FIG. 7, the axial length of the flange portion 12b is the same as the axial length of the case body 12a. These are appropriately selected depending on the configuration of the counterpart member.

  Moreover, as shown in FIG. 8, it is good also as a structure which couple | bonds the flange part 12b, after giving the knurling process to the outer peripheral surface of the case main body 12a. Further, the flange portion 12b may be plastically coupled to the case main body 12a. Moreover, it is good also as a structure by which the flange part 12b is couple | bonded with the case main body 12a with a spline.

  Of course, the case main body 12a (adjacent portion 22) and the flange portion 12b (attached portion 21) may be fixed with bolts as shown in FIGS. Needless to say, a stronger fixation can be obtained.

  In the embodiment, the case 12 is separated into the case main body 12a and the flange portion 12b. However, the present invention is not limited to this. For example, as shown in FIGS. 9 to 11, the case 12 may be divided in the case main body 12 a. Specifically, in the case 12 shown in FIGS. 9 to 11, the attached portion 21 having a portion for fixing a bolt (not shown) as a fastening portion attached to the first arm has a flange portion 12b, The flange portion 12 has a protruding portion 21b that protrudes radially inward from the inner peripheral portion. The projecting portion 21b is formed in a cylindrical shape that is thinner than the case body 12a. In the case 12 shown in FIGS. 9 and 10, the projecting portion 21b is longer in the axial direction than the flange portion 12b. Yes. And the overhang | projection part 21b comprises a part of outer peripheral part of the case main body 12a. On the other hand, the adjacent portion 22, which is a portion where the internal teeth 24 are disposed, is formed in a shape in which a portion corresponding to the protruding portion 21b is cut out of the outer peripheral portion of the case body 12a. That is, the outer peripheral portion of the adjacent portion 22 has a shape in which the outer peripheral surface is recessed so that one end portion in the axial direction is left. This recessed portion has a shape with a constant outer diameter in the axial direction. And the to-be-attached part 21 is externally fitted by the adjacent part 22 from the other end part side of the axial direction of the case main body 12a. And the outer peripheral surface in the one end part of the axial direction in the adjacent part 22 and the outer peripheral surface in the overhang | projection part 21b of the to-be-attached part 21 are a flush state.

  On the other hand, in the case 12 shown in FIG. 11, the axial length of the overhanging portion 21b is different from the axial length of the overhanging portion 21b of the attached portion 21 shown in FIGS. That is, in the case 12 of FIG. 11, the axial length of the overhanging portion 21b is formed shorter than the axial length of the flange portion 12b. And the inner peripheral surface of the flange part 12b is overlaid on the outer peripheral surface of the one end part of the adjacent part 22 in the axial direction.

  As shown in FIGS. 12-14, the overhang | projection part 21b may be formed in the shape covering the whole outer peripheral part of the case main body 12a. That is, in the configuration shown in FIGS. 9 to 11, one end portion of the adjacent portion 22 in the axial direction also forms the outer peripheral surface of the case main body 12 a, but unlike this, FIGS. In the configuration shown in FIG. 2, the adjacent portion 22 is not exposed to the outside. In this configuration, one end portion in the axial direction of the overhanging portion 21b may protrude from the one end portion in the axial direction of the adjacent portion 22 in the axial direction. Since the tip portion 21c of the protruding portion 21b protruding in the axial direction from the adjacent portion 22 is used as a portion into which the oil seal is fitted, by changing the axial length of the tip portion 21c according to the customer's request, Can be easily changed to a double oil seal type. In addition, the axial direction edge part (part located in the axial direction outer side with respect to the pin groove 12d) of the adjacent part 22 is a part where the main bearing 26 is mounted.

  In the mounted portion 21, the rear end portion 21 d, which is the end portion on the opposite side of the front end portion 21 c, protrudes inward in the radial direction and engages with an engagement groove formed at the axial end portion of the adjacent portion 22. ing. The attached portion 21 is positioned with respect to the adjacent portion 22 by the rear end portion 21 d being locked in the engaging groove of the adjacent portion 22.

10 Eccentric oscillating gear device 12 Case 12d Pin groove (internal tooth groove)
14 Carrier 18 Reduction mechanism 21 Mounted portion 21a Bolt insertion hole (insertion hole)
21b Overhang portion 21c Tip portion 22 Adjacent portion 22a Fastening hole (fastening hole)
24 Internal teeth 30 End plate portion 31 Base portion 32 Substrate portion 33 Shaft portion 44 Transmission gear 46 Crankshaft 46a First eccentric portion 46b Second eccentric portion 48a First swing gear 48b Second swing gear

Claims (4)

A gear device for generating a relative rotation at a rotational speed reduced with respect to an input rotational speed between a first member and a second member,
A crankshaft having an eccentric portion;
A rocking gear having a through-hole into which the eccentric part is inserted and having a tooth part;
A case configured to be attachable to one of the first member and the second member;
A carrier configured to be attachable to the other of the first member and the second member,
The carrier rotatably supports the crankshaft, and the case has internal teeth that mesh with teeth of the swing gear;
The case and the carrier are concentrically rotatable relative to each other by the swing of the swing gear accompanying the rotation of the crankshaft,
The case is a part to be attached having a part for fixing a fastener attached to the one of the first member and the second member, and a part adjacent to the part to be attached, An eccentric oscillating gear device having a configuration in which an adjacent portion, which is a portion where an internal tooth is disposed, is formed separately, and the attached portion is assembled to the adjacent portion.   The eccentric oscillating gear device according to claim 1, wherein the attached portion is positioned by fitting into the adjacent portion. An insertion hole through which a fastener can be inserted is formed in the attached portion, and a fastening hole in which the fastener is fastened is formed in the adjacent portion,
The eccentric oscillating gear device according to claim 1, wherein the attached portion and the adjacent portion are fastened to each other by the fastener.   The eccentric oscillating gear device according to claim 3, wherein the fastening hole communicates with an internal gear groove in which the internal teeth are disposed.

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