JP2017155772A - Gear device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gear device capable of sufficiently assuring a transmission torque while restricting increasing in cost and at the same time reducing possibility that a trouble occurs against rotation of a crank shaft.SOLUTION: A gear device X1 comprises a carrier 3 having a central hole 32c arranged along a rotating axis C1 into which an output shaft part 100 is press-fitted and a crank shaft hole 32e; and a crank shaft 5 supported at an inner peripheral surface 32f of the crank shaft hole 32e. An inner peripheral surface 32d of the central hole 32c has convexoconcave parts 300 engaged with convexoconcave parts 101 of the output shaft part 100. The convexoconcave parts 300 include several side surfaces 303 connecting the outermost surface 301 with the innermost surface 302 and inclined in respect to a radial direction of the rotating axis C1. Each of the side surfaces 303 is formed at a second location R2 adjacent a first location R1 included in an area where the central hole 32c and the crank shaft hole 32e are oppositely faced to each other.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a gear device.

  In recent years, various gear devices have been developed in various technical fields such as industrial robots and machine tools. As an example of such a gear device, Patent Document 1 discloses an outer cylinder having internal teeth, a crankshaft that can rotate around an axis, and a gear that meshes with the internal teeth of the outer cylinder in accordance with the rotation of the crankshaft. A gear device is described that includes an external gear that rotates and rotates, and a carrier that rotatably supports the crankshaft and that rotates relative to the outer cylinder in response to the swinging rotation of the external gear. . The carrier of this gear device is provided with a crankshaft hole in which the crankshaft is disposed, and a through hole into which an input gear for inputting torque to the crankshaft is inserted. The crankshaft hole and the through hole are provided in the carrier. Through the axis of rotation.

  In the gear device of Patent Document 1, an input gear inserted into the through hole from one side in the direction of the rotation shaft inputs torque to the crankshaft, whereby the crankshaft rotates. Then, according to the rotation of the crankshaft, the external gear rotates and rotates, whereby the carrier rotates about the rotation axis.

JP 2009-185986 A

  In the gear device of Patent Document 1, in order to transmit the rotation of the carrier to the counterpart member, the counterpart member is directly attached to the axial end surface of the carrier using a screw hole formed in the axial end surface of the carrier. .

  On the other hand, instead of directly attaching the counterpart member to the end surface in the axial direction of the carrier, the rotation of the carrier may be transmitted to the counterpart member via the output shaft portion that can rotate around the rotation axis. In this case, the output shaft portion may be formed integrally with the carrier so as to extend to the opposite side of the input portion gear along the center of the rotation axis of the carrier, or formed separately from the carrier and opposite to the input gear. It may be press-fitted into the through-hole of the carrier from the side.

  However, when the output shaft portion is formed integrally with the carrier, a process for forming the output shaft portion is required in the carrier manufacturing process, and the manufacturing cost increases. On the other hand, when the output shaft portion is press-fitted into the through hole of the carrier, the output shaft portion and the carrier are not in contact with each other in the circumferential direction, so that the transmission torque from the carrier to the output shaft portion is reduced.

  Therefore, in order to ensure sufficient transmission torque from the carrier to the output shaft portion, for example, the outer peripheral surface of the output shaft portion and the inner peripheral surface of the carrier surrounding the through hole are formed in an uneven shape over the entire circumferential direction. It is possible to do. As a result, the outer peripheral surface of the output shaft portion meshes with the inner peripheral surface of the carrier, and the outer peripheral surface of the output shaft portion and the inner peripheral surface of the carrier are in contact with each other in the circumferential direction. Can be secured. However, in this case, a strong force is applied to the outer side in the radial direction on the relatively thin portion of the carrier located between the through hole and the crankshaft hole by press-fitting the output portion into the through hole. In this case, a strong force is also applied to the crankshaft supported by the inner peripheral surface of the crankshaft hole, which may hinder the rotation of the crankshaft.

  The present invention has been made from the above viewpoint, and an object of the present invention is to provide a gear device that can sufficiently secure transmission torque while suppressing an increase in cost and can reduce the possibility of hindrance to rotation of the crankshaft. It is to provide.

  The gear device according to the present invention includes a center hole provided along the rotation shaft while being press-fitted with an output shaft portion having irregularities formed on the outer peripheral surface, and the center hole in the radial direction around the rotation shaft. A carrier having a crankshaft hole provided so as to be lined up; and a crankshaft that is supported on an inner peripheral surface of the crankshaft hole and that rotates the carrier relative to an outer cylinder about the rotating shaft; The inner peripheral surface of the central hole has a concavo-convex portion that meshes with the concavo-convex portion of the output shaft portion, and the concavo-convex portion is a plurality of outermost portions in the radial direction. The outermost part, a plurality of innermost parts located on the innermost side in the radial direction, and a plurality of side surfaces that connect the outermost part and the innermost part and are inclined with respect to the radial direction, Inner circumference of the central hole Has a first part included in a region where the central hole and the crankshaft hole are opposed to each other in the radial direction, and a second part adjacent to the first part in the circumferential direction, Each said side is formed in the said 2nd site | part.

  In the above gear device, since the output shaft portion is fixed to the carrier by press-fitting the output shaft portion into the center hole of the carrier, the cost is lower than when the carrier and the output shaft portion are integrally formed. The increase can be suppressed.

  Further, in the above gear device, the inner peripheral surface of the central hole has an uneven portion that meshes with the uneven portion of the output shaft portion, and a plurality of side surfaces included in the uneven portion are on the outer peripheral surface of the output shaft portion in the circumferential direction. Therefore, the transmission torque from the carrier to the output shaft portion can be sufficiently ensured.

  By the way, when the output shaft portion is press-fitted into the central hole, the outer peripheral surface of the output shaft portion is pressed against a plurality of side surfaces included in the uneven portion. Here, the plurality of side surfaces are inclined with respect to the radial direction around the rotation axis. For this reason, when the output shaft portion is press-fitted into the central hole, the force applied to the outer side in the radial direction from the output shaft portion to the inner peripheral surface of the central hole becomes larger in the region where the plurality of side surfaces are formed.

  Therefore, in the above gear device, in order to prevent a strong force from being applied to a relatively thin portion located between the center hole and the crankshaft hole in the carrier, of the inner peripheral surface of the center hole, A plurality of side surfaces are not formed in the first portion included in the region where the central hole and the crankshaft hole face each other in the radial direction, and a plurality of side surfaces are formed only in the second portion adjacent to the first portion in the circumferential direction. doing. Thereby, it can suppress that strong force is added to the crankshaft supported by the internal peripheral surface of a crankshaft hole, and can reduce possibility that the rotation of the said crankshaft will be obstructed.

  As described above, in the above gear device, it is possible to sufficiently secure a transmission torque from the carrier to the output shaft portion while suppressing an increase in the manufacturing cost of the carrier, and to reduce the possibility of hindering the rotation of the crankshaft. .

  In said gear apparatus, it is preferable that the said 1st site | part is a curved surface extended along the said circumferential direction, and is connected with the said radial outer end in the side surface nearest to the said 1st site | part among each said side surface. .

  In this case, it is preferable that the length from the rotating shaft to the first portion is equal to or longer than the length from the rotating shaft to the outermost portion.

  According to said structure, even if the unevenness | corrugation formed in the outer peripheral surface of an output shaft part has comprised the uniform shape over the whole region of the circumferential direction, the said output shaft part is press-fit in a center hole. It is possible. For this reason, it is not necessary to form unevenness only on a part of the outer peripheral surface of the output shaft portion in accordance with the uneven portion formed on the inner peripheral surface of the central hole, and the conventional output shaft portion can be used as it is. .

  In the above gear device, it is preferable that the first part is a curved surface extending along the circumferential direction, and is connected to the radially inner end of the side surface closest to the first part among the side surfaces. .

  According to the above configuration, the first portion extends along the circumferential direction and is connected to the radially inner end of the side surface, and in the radial direction compared to the case where the first portion is connected to the radially outer end of the side surface. It is separated from the crankshaft hole. That is, in the above gear device, the thickness of the portion of the carrier between the center hole and the crankshaft hole can be increased as compared with the case where the first portion is connected to the outer end of the side surface. For this reason, it is possible to further reduce the possibility of hindrance to the rotation of the crankshaft by press-fitting the output shaft portion into the central hole.

  In the gear device according to the present invention, it is possible to sufficiently ensure the transmission torque while suppressing an increase in cost, and it is possible to reduce the possibility of hindering the rotation of the crankshaft.

It is a schematic sectional drawing of the gear apparatus of a 1st embodiment. It is the time of the schematic cross section of the gear apparatus which follows the AA line shown in FIG. It is the schematic front view which looked at the gear apparatus of 1st Embodiment from the 2nd axial direction end surface side of the carrier. It is the figure which expanded the center hole of the carrier in FIG. It is a schematic sectional drawing of the output shaft part press-fitted in the center hole of FIG. In the gear apparatus of 2nd Embodiment, it is the figure which showed the part similarly to FIG. It is a schematic sectional drawing of the output shaft part press-fitted in the center hole of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, each drawing referred to below shows only the main components in a simplified manner among the components of the gear device X1 according to the present embodiment for convenience of explanation. Therefore, the gear device X1 according to the present embodiment can include arbitrary components not shown in the drawings referred to in this specification.

<First Embodiment>
As shown in FIGS. 1 and 2, the gear device X <b> 1 is an eccentric oscillating gear device, and includes an outer cylinder 2, a carrier 3, a oscillating gear 4, a crankshaft 5, and a transmission gear 7. It is equipped with. In the gear device X1, the input torque is transmitted to the crankshaft 5 via the transmission gear 7, so that the crankshaft 5 rotates, and the swinging gear 4 swings and rotates in accordance with this, so that the outer cylinder 2 and the carrier 3 rotate relatively.

  The outer cylinder 2 has a substantially cylindrical shape with the rotation axis C1 as the central axis. A large number of pin grooves are formed on the inner peripheral surface 2 a of the outer cylinder 2. Each pin groove is disposed so as to extend in the direction of the rotation axis C1, and has a semicircular cross-sectional shape in a cross section orthogonal to the direction of the rotation axis C1. The pin grooves are arranged at equal intervals in the circumferential direction of the outer cylinder 2.

  The gear device X <b> 1 further includes a plurality of internal teeth pins 8 attached to the inner peripheral surface 2 a of the outer cylinder 2. Each internal tooth pin 8 has a cylindrical shape extending in the direction of the rotation axis C1. Each internal tooth pin 8 is attached to each pin groove formed on the inner peripheral surface 2 a of the outer cylinder 2.

  The outer cylinder 2 is formed with a plurality of mounting holes 2b that penetrate the outer cylinder 2 in the direction of the rotation axis C1. The mounting holes 2b are arranged at equal intervals in the circumferential direction of the outer cylinder 2. Each attachment hole 2b is utilized, for example, when attaching a counterpart member (not shown) to the outer cylinder 2. When the counterpart member attached to the outer cylinder 2 is a non-rotating base member, the outer cylinder 2 is a fixed-side member in the gear device X1.

  The carrier 3 is configured to be rotatable relative to the outer cylinder 2 around the rotation axis C1. The carrier 3 is configured to sandwich the oscillating gear 4 in the direction of the rotation axis C <b> 1, and is arranged concentrically with the outer cylinder 2. The carrier 3 includes a first member 31 and a second member 32 that face each other in the direction of the rotation axis C1. The first member 31 and the second member 32 are fastened to each other via the fastening member B.

  The first member 31 has a substantially disk shape. A part of the first member 31 is located inside the outer cylinder 2, and the remaining part is located outside the outer cylinder 2 in the direction of the rotation axis C <b> 1. The first member 31 includes a facing surface facing the second member 32 in the direction of the rotation axis C1 and a first axial end surface 31A located on the opposite side of the surface.

  The first member 31 has a central hole 31a, a crankshaft hole 31b, and an insertion hole 31d.

  The central hole 31a is formed in the central portion of the first member 31 so as to penetrate the first member 31 along the rotation axis C1 from the first axial end surface 31A to the opposing surface. The center of the central hole 31a is the rotation axis C1.

  The crankshaft hole 31b is a hole in which a part of the crankshaft 5 is accommodated. The crankshaft hole 31 b is aligned with the central hole 31 a in the radial direction of the carrier 3. In the present embodiment, the three crankshaft holes 31b are arranged in the circumferential direction of the carrier 3 outside the central hole 31a. Each crankshaft hole 31b is a through hole that penetrates the first portion 31 from the first axial end surface 31A to the opposing surface in the direction of the rotation axis C1. The number of crankshaft holes 31b is arbitrary and can be changed as appropriate according to the number of crankshafts 5 described later.

  The insertion hole 31d is a hole into which the fastening member B is inserted. A plurality of insertion holes 31 d are formed outside the central hole 31 a in the radial direction of the carrier 3. The insertion hole 31d is formed so as to penetrate the carrier 3 in the direction of the rotation axis C1 from the first axial end surface 31A to the opposing surface, and accommodates the fastening member B and the head.

  The second member 32 includes a substantially disk-shaped substrate portion 32a and a shaft portion 32b extending from the substrate portion 32a toward the first member 31 side.

  A part of the substrate part 32a is located inside the outer cylinder 2, and the remaining part is located outside the outer cylinder 2 in the direction of the rotation axis C1. The substrate portion 32a includes a shaft surface connected to the shaft portion 32b in the direction of the rotation axis C1, and a second axial end surface 32A located on the opposite side of the shaft surface.

  The shaft portion 32b extends in the direction of the rotation axis C1 from the shaft surface of the substrate portion 32a toward the first member 31. A plurality of shaft portions 32 b are provided side by side in the circumferential direction of the carrier 3. In the present embodiment, the second member 32 has three shaft portions 32b.

  The second member 32 is formed with a center hole 32c, a crankshaft hole 32e, and a female screw hole 32g.

  The central hole 32c is formed in the central portion of the substrate portion 32a so as to penetrate the substrate portion 32a of the second member 32 from the second axial end surface 32A to the shaft surface along the rotation axis C1. The center of the central hole 32c is the rotation axis C1.

  The crankshaft hole 32e is a hole in which a part of the crankshaft 5 is accommodated. The crankshaft hole 32 e is aligned with the central hole 32 c in the radial direction of the carrier 3. In the present embodiment, the three crankshaft holes 32e are arranged in the circumferential direction of the carrier 3 outside the central hole 32c. Each crankshaft hole 32e is a through hole that penetrates the substrate portion 32a of the second member 32 from the second axial end surface 32A to the shaft surface in the direction of the rotation axis C1. Note that the number of the crankshaft holes 32e is arbitrary, and is appropriately changed according to the number of crankshafts 5 described later.

  The female screw hole 32g is a hole into which the male screw portion of the fastening member B is screwed. The female screw hole 32g is formed so that a part of the end surface of the shaft portion 32b that contacts the facing surface of the first member 31 is recessed. The female screw hole 32g is continuous with the insertion hole 31d of the first member 31 in the direction of the rotation axis C1. The fastening member B is inserted into the carrier 3 through the insertion hole 31d, and the male screw portion of the fastening member B is screwed into the female screw hole 32g of the shaft portion 32b, thereby connecting the first member 31 and the second member 32 together. Conclude.

  The crankshaft 5 is accommodated in the crankshaft holes 31b and 32d. A part of the crankshaft 5 is rotatably supported by an inner peripheral surface 31c of the crankshaft hole 31b and an inner peripheral surface 32f of the crankshaft hole 32e. Specifically, the gear device X1 further includes crank bearings 6A and 6B that allow rotation of the crankshaft 5 with respect to the carrier 3, and the crankshaft 5 is connected to the inner peripheral surfaces 31c and 32f via the crank bearings 6A and 6B. It is supported by. In the present embodiment, three crankshafts 5 are provided side by side in the circumferential direction of the carrier 3. The number of crankshafts 5 is arbitrary, and can be changed as appropriate according to the usage mode of the gear device X1.

  The crankshaft 5 includes a shaft main body 51 extending in the direction of the rotation axis C <b> 1 and eccentric portions 52 and 53 that are eccentric with respect to the shaft main body 51.

  The shaft body 51 has a smaller diameter than the crankshaft holes 31b and 32e. The shaft body 51 extends from the crankshaft hole 32e to the outside of the first axial end surface 31A in the direction of the rotation axis C1. The shaft body 51 is rotatably supported on the inner peripheral surface 31c via the crank bearing 6A in the crankshaft hole 31b, and is rotatably supported on the inner peripheral surface 32f via the crank bearing 6B in the crankshaft hole 32e. Has been.

  The eccentric parts 52 and 53 are attached to an intermediate portion of the shaft main body 51 so as to be eccentric with respect to the rotation center axis of the shaft main body 51. Oscillating gears 4 to be described later are attached to the eccentric portions 52 and 53 via roller bearings. Thereby, the eccentric parts 52 and 53 and the oscillating gear 4 are relatively rotatable.

  The oscillating gear 4 is located in the outer cylinder 2 and is sandwiched between the first member 31 and the substrate portion 32a of the second member 32 in the direction of the rotation axis C1. The oscillating gear 4 includes a first oscillating gear 41 attached to the first eccentric portion 52 and a second oscillating gear 42 attached to the second eccentric portion 53.

  The oscillating gears 41 and 42 have an outer diameter slightly smaller than the inner diameter of the outer cylinder 2, and a plurality of external teeth are formed on the outer peripheral surface thereof. The number of external teeth formed on the outer peripheral surfaces of the oscillating gears 41 and 42 is slightly smaller than the number of internal tooth pins 8. Thus, the first oscillating gear 41 and the second oscillating gear 42 can oscillate and rotate at different phases so that each external tooth meshes with each internal tooth pin 8 inside the outer cylinder 2. .

  The first rocking gear 41 has a center hole 41a corresponding to the positions of the center holes 31a and 32c, an insertion hole 41b into which the shaft portion 32b is inserted, and a crankshaft hole 41c into which the first eccentric portion 52 is inserted. , Is formed. The central hole 41a, the insertion hole 41b, and the crankshaft hole 41c penetrate the first swing gear 41 in the direction of the rotation axis C1.

  The second rocking gear 42 has a center hole 42a corresponding to the positions of the center holes 31a and 32c, an insertion hole 42b into which the shaft portion 32b is inserted, and a crankshaft hole 42c into which the second eccentric portion 53 is inserted. , Is formed. The center hole 42a, the insertion hole 42b, and the crankshaft hole 42c penetrate the first swing gear 41 in the direction of the rotation axis C1.

  In the present embodiment, the oscillating gear 4 has two oscillating gears, ie, a first oscillating gear 41 and a second oscillating gear 42. However, the present invention is not limited to this, and one oscillating gear. May be included, or three or more oscillating gears may be included.

  The transmission gear 7 transmits input torque to the crankshaft 5 to rotate the crankshaft 5. In the present embodiment, three transmission gears 7 are provided corresponding to the positions of the three crankshafts 5. The transmission gear 7 is located on the opposite side of the second member 32 across the first member 31 in the direction of the rotation axis C1. The transmission gear 7 is attached to the shaft main body 51 of the crankshaft 5 that protrudes outside the first axial end surface 31A in the direction of the rotation axis C1. The movement of the transmission gear 7 in the direction of the rotation axis C1 is restricted by a retaining ring attached to the small diameter portion 51a of the shaft body 51 so as to sandwich the transmission gear 7 from both sides in the direction of the rotation axis C1.

  In the present embodiment, the transmission gear 7 is located on the opposite side of the second member 32 across the first member 31 in the direction of the rotation axis C1, but is not limited thereto. The transmission gear 7 may be located between the first eccentric part 52 and the second eccentric part 53, for example. That is, the arrangement of the transmission gear 7 is arbitrary, and can be appropriately changed according to the mode of the gear device X1.

  The transmission gear 7 has a plurality of external teeth on the outer peripheral surface thereof, and an input shaft of a motor (not shown) is engaged with the plurality of external teeth to transmit the input torque of the motor to the crankshaft 5. . Then, as the eccentric parts 52 and 53 of the crankshaft 5 rotate, the oscillating gear 4 oscillates and rotates in the outer cylinder 2 according to the rotation. As a result, the outer cylinder 2 and the carrier 3 rotate relative to each other.

  Here, as shown in FIG. 1, on the second axial end surface 32A side of the carrier 3 in the direction of the rotation axis C1, there is provided an output shaft portion 100 for transmitting the rotation of the carrier 3 to a mating member (not shown). It has been.

  A part of the output shaft portion 100 is press-fitted into the central hole 32 c of the second member 32 in the carrier 3, whereby the output shaft portion 100 is fixed to the carrier 3. The remaining portion of the output shaft portion 100 protrudes outside the second axial end surface 32A in the direction of the rotation axis C1. As a result, the output shaft portion 100 rotates about the rotation axis C1 in accordance with the rotation of the carrier 3, and this rotation is transmitted to an unillustrated counterpart member disposed on the second axial end face 32A side. It will be.

  Here, the shape of the inner peripheral surface 32d of the central hole 32c in the carrier 3 and the shape of the output shaft portion 100 press-fitted into the central hole 32c will be described in detail with reference to FIGS.

  FIG. 3 shows a first region E1 in which the central hole 32c and the crankshaft hole 32e face each other in the radial direction centered on the rotation axis C1, and the central hole 32c and the crankshaft hole 32e in the radial direction. The 2nd area | region E2 which is an area | region which does not oppose is shown. Specifically, when a tangent is drawn to each crankshaft hole 42c with the rotation axis C1 as the center, a region between the tangents including the crankshaft hole 42c is the first region E1, and excludes the first region E1. The region between the tangent lines is the second region.

  In the present embodiment, three crankshaft holes 32e are formed in the second member 32 of the carrier 3 side by side in the circumferential direction with the rotation axis C1 as the center, so that the three first regions E1 and the three first Two regions E2 are arranged in the circumferential direction.

  As shown in FIG. 3, the inner peripheral surface 32 d of the central hole 32 c has an uneven portion 300 and a curved surface 400 that extends smoothly along the circumferential direction and continues to the uneven portion 300. In the present embodiment, the inner peripheral surface 32d of the central hole 32c has three uneven portions 300 and three curved surfaces 400, and the uneven portions 300 and the curved surface 400 are alternately continued in the circumferential direction. It is almost circular.

  Here, FIG. 4 is an enlarged view of the central hole 32c shown in FIG. As shown in FIG. 4, the central hole 32c has a first part R1 included in the first region E1 and a second part R2 that is continuous in the circumferential direction with respect to the first part R1. In the central hole 32c, the first portion R1 and the second portion R2 are alternately continued in the circumferential direction, and thereby have a substantially circular shape.

  The uneven portion 300 is formed in the second region R2. Specifically, in the present embodiment, each of the three uneven portions 300 is formed only in each of the three second regions R2. For this reason, the uneven | corrugated | grooved part 300 is not formed in 1st site | part R1, but the said 1st site | part R1 becomes the curved surface 400 extended smoothly along the circumferential direction.

  Since the curved surface 400 is connected to the uneven portion 300, when the uneven portion 300 is formed only in a part of the second part R2, a part of the curved surface 400 extends to the second part R2. Also good.

  The uneven part 300 has an outermost surface 301, an innermost surface 302, and a side surface 303, and the curved surface 400 is connected to the side surface 303 in the second region E2.

  The outermost surface 301 is a surface farthest from the rotation axis C <b> 1 in the radial direction in the concavo-convex portion 300. The outermost surface 301 in the present embodiment corresponds to the outermost part in the present invention. The uneven portion 300 includes a plurality of outermost surfaces 301. In the present embodiment, each outermost surface 301 extends smoothly along the circumferential direction.

  The innermost surface 302 is a surface of the concavo-convex portion 300 that is closest to the rotation axis C1 in the radial direction. The innermost surface 302 in the present embodiment corresponds to the innermost portion in the present invention. The uneven portion 300 includes a plurality of innermost surfaces 302. Each innermost surface 302 is located in a region between the outermost surfaces 301 adjacent to each other in the circumferential direction. In the present embodiment, each innermost surface 302 extends smoothly along the circumferential direction.

  The side surface 303 is a surface that intersects the circumferential direction, and connects the outermost surface 301 and the innermost surface 302 that are adjacent to each other in the circumferential direction. The uneven portion 300 includes a plurality of side surfaces 303. In this embodiment, since the whole uneven | corrugated | grooved part 300 is formed in 2nd site | part R2, the some side surface 303 is also formed in 2nd site | part R2.

  Each side surface 303 is inclined with respect to the radial direction. Specifically, two curved surfaces connected to both end portions of the outermost surface 301 are inclined in directions opposite to each other with respect to the radial direction. For this reason, the site | part which the outermost surface 301 and the two curved surfaces connected to the both ends of the said outermost surface 301 among the uneven | corrugated | grooved parts 300 have comprised the taper shape dented toward the outer side of radial direction.

  Each side surface 303 includes an inner end 303a located on the innermost side and an outer end 303b located on the outermost side in the radial direction. The inner end 303a is connected to the end of the outermost surface 302 in the circumferential direction, and the outer end 303b is connected to the end of the outermost surface 301 in the circumferential direction.

  Out of each side surface 303, the outer end 303 b of the side surface 303 closest to the first region R <b> 1 in the circumferential direction is connected to the curved surface 400.

  In the present embodiment, the length L2 between the side surfaces 303 adjacent to each other in the circumferential direction in the second region E2 is shorter than the length L1 of the curved surface 400 extending in the circumferential direction in the first region E1.

  In the present embodiment, the radius r1 of the central hole 32c located in the first region E1 is set to the same length as the maximum radius r2 of the central hole 32c located in the second region E2. The radius r1 is the length from the rotation axis C1 to the curved surface 400, and the maximum radius r2 is the length from the rotation axis C1 to the outermost surface 301. Note that the radius r1 does not have to be the same length as the maximum radius r2, but may be any length as long as the maximum radius r2.

  Next, FIG. 5 shows a cross section of a portion of the output shaft portion 100 that is press-fitted into the central hole 32c shown in FIG. The diameter of the output shaft portion 100 is set to a diameter that allows the center hole 32c to be press-fitted. The outer peripheral surface 100A of the output shaft portion 100 includes irregularities 101 that meander along the circumferential direction around the rotation axis C1. In this embodiment, the unevenness | corrugation 101 is formed uniformly over the whole outer peripheral surface 100A in the circumferential direction.

  In addition, the unevenness | corrugation 101 does not need to be formed over 100 A of outer peripheral surfaces in the circumferential direction, for example, may be formed only in the position corresponding to the uneven | corrugated | grooved part 300 in the internal peripheral surface 32d of the center hole 32c.

  The unevenness 101 on the outer peripheral surface 100 </ b> A in the output shaft portion 100 is formed in a shape corresponding to the unevenness portion 300 on the inner peripheral surface 32 d in the central hole 32 c of the carrier 3. A part of the unevenness 101 is engaged with the unevenness portion 300 in a state where the output shaft portion 100 is press-fitted in the central hole 32c. For this reason, each side surface 303 on the inner peripheral surface 32f of the central hole 32c is in contact with the outer peripheral surface 100A of the output shaft portion 100 into which the central hole 32c is press-fitted in the circumferential direction.

  As described above, in the gear device X1, since the output shaft portion 100 is fixed to the carrier 3 by press-fitting the output shaft portion 100 into the center hole 32c in the second member 32 of the carrier 3, the output from the carrier 3 An increase in cost can be suppressed as compared with the case where the shaft portion 100 is integrally formed.

  Further, in the gear device X1, the inner peripheral surface 32d of the central hole 32c has an uneven portion 300 that meshes with the uneven portion 101 on the outer peripheral surface 100A of the output shaft portion 100. Therefore, the plurality of side surfaces 303 included in the uneven portion 300 of the inner peripheral surface 32d are in contact with the outer peripheral surface 100A of the output shaft portion 100 in the circumferential direction around the rotation axis C1. Thereby, the transmission torque from the carrier 3 to the output shaft portion 100 can be sufficiently ensured.

  By the way, when the output shaft portion 100 is press-fitted into the central hole 32c so as to be engaged with the uneven portion 300 of the inner peripheral surface 32d, the outer peripheral surface 100A of the output shaft portion 100 is provided on the plurality of side surfaces 303 included in the uneven portion 300. Will be pressed. Here, the plurality of side surfaces 303 are inclined with respect to the radial direction around the rotation axis C1. For this reason, when the output shaft portion 100 is press-fitted into the central hole 32c, the force applied from the output shaft portion 100 to the inner peripheral surface 32d of the central hole 32c on the outer side in the radial direction forms a plurality of side surfaces 303. The larger the area.

  Therefore, in the gear device X1, in order to suppress a strong force from being applied to a relatively thin portion located between the center hole 32c and the crankshaft hole 32e in the substrate portion 32a of the carrier 3, the inner peripheral surface In 32d, the plurality of side surfaces 303 are not formed in the first region R1 included in the first region E1 in which the central hole 32c and the crankshaft hole 32e face each other in the radial direction. A plurality of side surfaces 303 are formed in the second region R2 included in the second region E2 where the central hole 32c and the crankshaft hole 32e do not face each other in the radial direction. Thereby, it can suppress that strong force is added with respect to the crankshaft 5 supported by the internal peripheral surface 32f of the crankshaft hole 32e, and can reduce possibility that the rotation of the said crankshaft 5 will be obstructed.

  Further, in the gear device X1, the curved surface 400 (first portion R1) extending along the circumferential direction around the rotation axis C1 is connected to the outer end 303b of the side surface 303 located on the side closest to the curved surface 400. . Thereby, the radius r1 of the central hole 32c in the first region E1 is set to be equal to or larger than the maximum radius r2 of the central hole 32c in the second region E2. For this reason, even if the unevenness | corrugation 101 in 100 A of outer peripheral surfaces of the output shaft part 100 is a uniform shape over the whole region of the circumferential direction, it is possible to press-fit the said output shaft part 100 in the center hole 32c. Therefore, it is not necessary to form the unevenness 101 of the output shaft portion 100 according to the unevenness portion 300 of the central hole 32c, and the conventional output shaft portion 100 can be used as it is.

Second Embodiment
Next, the gear device X1 according to the second embodiment will be described with reference to FIGS. In the present embodiment, only parts different from the first embodiment will be described, and descriptions of the same structure, operation, and effect as those of the first embodiment will be omitted.

  As shown in FIG. 6, the gear device X1 of the second embodiment is different from the gear device X1 of the first embodiment in the shape of the inner peripheral surface 32d of the center hole 32c.

  Specifically, in the second embodiment, the curved surface 400 that smoothly extends in the circumferential direction in the first region E1 is connected to the inner end 303a of the side surface 303 that is closest to the curved surface 400 in the circumferential direction. For this reason, in the second embodiment, the radius of the central hole 32c in the first region E1 is smaller than the maximum radius of the central hole 32c in the second region E2.

  Here, FIG. 7 shows a cross section of a portion of the output shaft portion 100 that is press-fitted into the central hole 32c of FIG. As shown in FIG. 7, the outer peripheral surface 100 </ b> A of the output shaft portion 100 includes unevenness 101 that meanders along the circumferential direction, and a curved surface 102 that extends smoothly along the circumferential direction.

  In the present embodiment, on the outer circumferential surface 100A, three irregularities 101 are formed corresponding to the three irregularities 300 on the inner circumferential surface 32d of the central hole 32c, and three curved surfaces corresponding to the three curved surfaces 400 are formed. 102 is formed. That is, in this embodiment, the three unevenness | corrugations 101 and the three curved surfaces 102 are alternately continued in the circumferential direction. As a result, the output shaft portion 100 is press-fitted into the central hole 32 c so that the unevenness 101 is engaged with the unevenness portion 300.

  In the gear device X1 according to the second embodiment, the curved surface 400 (first portion R1) extends along the circumferential direction around the rotation axis C1 and is connected to the inner end 303a of the side surface 303. For this reason, compared with the case where the curved surface 400 is connected to the outer end 303b of the side surface 303, the thickness of the portion of the carrier 3 between the central hole 32c and the crankshaft hole 32e can be increased. For this reason, the possibility that the rotation of the crankshaft 5 is hindered by the press-fitting of the output shaft portion 100 into the central hole 32c can be further reduced.

  The present embodiment described above should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims for patent, and further includes meanings equivalent to the scope of claims for patent and all modifications within the scope.

  For example, in the above-described embodiment, each side surface 303 of the concavo-convex portion 300 is inclined with respect to the radial direction around the rotation axis C1, but this is not limitative. For example, each side surface 303 may extend along the radial direction.

  In the above-described embodiment, the concavo-convex portion 300 is formed over substantially the entire area of the second region E2 in the circumferential direction around the rotation axis C1, but the present invention is not limited to this. For example, the uneven | corrugated | grooved part 300 may be formed only in the center area | region except the area | region of the both ends close | similar to 1st area | region E1 among 2nd area | region E2.

  In the above embodiment, the uneven portion 300 is formed in a bent shape having the outermost surface 301, the innermost surface 302, and the side surface 303, but is not limited thereto. For example, the uneven portion 300 may have a smooth curved shape that meanders along the circumferential direction. In this case, the point farthest from the rotation axis C1 of the concavo-convex part 300 is the outermost part, and the point closest to the rotation axis C1 of the concavo-convex part 300 is the innermost part, connecting the outermost part and the innermost part. A smooth curved portion becomes the side surface 303.

C1 Rotating shaft R1 First part R2 Second part X1 Gear device 3 Carrier 5 Crankshaft 32c Central hole 32d Inner peripheral surface of central hole 32e Crankshaft hole 32f Crankshaft hole 100 Output shaft part 100A Outer peripheral surface of output shaft part 101 Concavity and convexity 300 Concavity and convexity 301 Outermost surface (outermost)
302 innermost surface (innermost)
303 Side surface 303a Inner end 303b Outer end 400 Curved surface

Claims (4)

A center hole provided along the rotation axis while an output shaft portion having irregularities formed on the outer peripheral surface is press-fitted, and a crankshaft provided so as to be aligned with the center hole in a radial direction around the rotation axis A carrier having pores;
A crankshaft supported by an inner peripheral surface of the crankshaft hole, and a crankshaft that rotates the carrier relative to an outer cylinder around the rotating shaft,
The inner peripheral surface of the central hole has an uneven portion that meshes with the uneven portion of the output shaft portion,
The concavo-convex portion connects the plurality of outermost portions located on the outermost side in the radial direction, the plurality of innermost portions located on the innermost side in the radial direction, the outermost portion and the innermost portion, and the radial direction. A plurality of side surfaces inclined with respect to
The inner peripheral surface of the central hole includes a first part included in a region where the central hole and the crankshaft hole face each other in the radial direction, and a second part adjacent to the first part in the circumferential direction. , And
Each said side is a gear apparatus currently formed in the said 2nd site | part.   2. The gear device according to claim 1, wherein the first portion is a curved surface extending along the circumferential direction, and is connected to an outer end in the radial direction on a side surface closest to the first portion among the side surfaces. .   The gear device according to claim 2, wherein a length from the rotation shaft to the first portion is equal to or longer than a length from the rotation shaft to the outermost portion.   2. The gear device according to claim 1, wherein the first portion is a curved surface extending along the circumferential direction, and is connected to an inner end in the radial direction on a side surface closest to the first portion among the side surfaces. .

Images