JP2010014241A - Eccentric reduction gear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve fluidity in lubricating oil between a carrier and an external teeth gear, while miniaturizing a regulating part and restraining the occurrence of damage in the regulating part, in an eccentric reduction gear provided with the regulating part for regulating the position of the external teeth gear to the carrier. <P>SOLUTION: The regulating parts 55 and 56 are formed as a plurality of projections 55a and 56a projecting toward the external teeth gear and abutting on the external teeth gear. The plurality of projections 55a and 56a are arranged so as to be dispersively arranged in the peripheral direction of the carriers 25 and 26. In the external teeth gear, parts 58a and 58b on which the plurality of projections 55a and 56a abut are formed as planes. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides an eccentric type in which an external gear meshing with a pin internal tooth rotates eccentrically with the rotation of the crankshaft and the position of the external gear with respect to a carrier that rotatably holds the crankshaft is regulated in the case. Related to reducer.

  In various industrial machines and the like, an eccentric type reduction gear is used as a reduction gear capable of realizing a large reduction ratio. As such an eccentric type speed reducer, in Patent Document 1, an external gear meshing with a pin internal tooth rotates eccentrically with rotation of the crankshaft in the case and is external to a carrier that rotatably holds the crankshaft. An eccentric speed reducer in which the position of the toothed gear is regulated is disclosed. In this eccentric type speed reducer, the carrier formed as the first flange body and the second flange body is provided with a restricting portion for restricting the axial position of the external gear with respect to the carrier over the entire circumference. ing. On the other hand, Patent Document 2 discloses an eccentric speed reducer in which the positions of the external gears are restricted, not the eccentric speed reducer in which the position of the external gear with respect to the carrier is restricted. In the eccentric type speed reducer of Patent Document 2, convex portions are provided on opposing surfaces of a plurality of external gears, and the positions of the external gears are restricted. And this convex part is provided with the notch part. Incidentally, in the eccentric type reduction gear of Patent Document 2, the outer surface of the external gear located on the outermost side in the axial direction is provided with an outer convex portion that is not provided with a notch. And the outer convex part formed over the perimeter of the external gear abuts on a bearing that holds the carrier formed as the first support flange and the second support flange rotatably with respect to the case, thereby The position of the external gear with respect to the bearing is regulated.

JP 2007-100903 (5th page, FIG. 1) JP 2006-64128 A (page 3-5, FIG. 1-8)

  In the eccentric type reduction gear disclosed in Patent Document 1, a restricting portion that restricts the position of the external gear is formed over the entire circumference of the carrier. For this reason, the flow of the lubricating oil in the case is prevented between the carrier and the external gear. On the other hand, in the eccentric type speed reducer disclosed in Patent Document 2, the lubricating oil flows between the external gears, but the lubricating oil is prevented from flowing between the external gear and the bearing with which the outer convex portion abuts. For this reason, the flow of the lubricating oil between the carrier and the external gear is hindered. Further, in the eccentric type reduction gear of Patent Document 2, since the convex portions that regulate the positions of the external gears are provided on the external gears that oscillate with each other, it is sufficient to abut even if they oscillate. A large-sized convex part with a large size is required. In the case of a small convex portion as disclosed in FIG. 7 of Patent Document 2, when the convex portions slide with each other as the external gear swings, the other side convex portion is moved at the corner portion of the convex portion. There is a risk of causing damage such as shaving.

  In view of the above circumstances, the present invention suppresses the occurrence of damage to the restricting portion and reduces the size of the restricting portion in the eccentric reduction gear provided with the restricting portion that restricts the position of the external gear with respect to the carrier. An object of the present invention is to provide an eccentric type speed reducer that can improve the fluidity of the lubricating oil between the carrier and the external gear.

  In order to achieve the above object, an eccentric speed reducer according to a first aspect of the present invention includes a case, a plurality of pin internal teeth formed as pin-shaped members disposed on the inner periphery of the case, and housed in the case. In addition, the external gear that has external teeth meshing with the pin internal teeth and the crank hole formed in the external gear pass through and rotate to eccentrically rotate the external gear. A crankshaft to be formed, an eccentric portion formed in the crankshaft, disposed in the crank hole and provided eccentric to a rotation center line of the crankshaft, and the eccentric portion in the crank hole An external gear bearing rotatably held with respect to the external gear, a carrier that rotatably holds one end side and the other end side of the crankshaft via a crankshaft bearing, and a pinio fixed to the carrier Includes an output shaft is mounted, it is formed on the carrier, and a regulating portion for regulating the position in the axial direction with respect to the carrier of the external gear abuts with the external gear. In the eccentric type reduction gear according to the first aspect of the invention, the restriction portion is formed as a plurality of protrusions that protrude toward the external gear and abut against the external gear, and the plurality of protrusions are It is provided so that it may disperse | distribute and arrange | position along the circumferential direction of the said carrier, The part which these protrusions contact | abut in the said external gear is formed in the plane, It is characterized by the above-mentioned.

  According to the present invention, the restriction portions that are formed on the carrier and restrict the position of the external gear in the axial direction (the axial direction of the external gear) with respect to the carrier are distributed and arranged along the circumferential direction of the carrier. It is formed as a plurality of protrusions that come into contact. For this reason, the lubricating oil in the case flows between the protrusions, and the fluidity of the lubricating oil between the carrier and the external gear can be improved. By improving the fluidity, the lubricating oil in the case is efficiently circulated and supplied to the crankshaft bearing and the external tooth bearing, and the lubricity of the crankshaft bearing and the external tooth bearing can also be improved. In addition, since a plurality of protrusions are formed on the carrier, the relative swinging range between the carrier-side protrusion and the external gear becomes smaller and the protrusion can be made smaller than when a restricting portion is provided between the external gears. It can be formed to reduce the size of the restricting portion. In addition, since the portion where the protrusion abuts on the external gear is formed into a flat surface, the protrusions do not slide with each other as the external gear swings. It is also possible to prevent damage such as scraping. For this reason, a protrusion can be further made small and the fluidity | liquidity of the lubricating oil between a carrier and an external gear can be improved.

  Therefore, according to the present invention, in the eccentric type reduction gear provided with the restriction portion for restricting the position of the external gear with respect to the carrier, it is possible to suppress the restriction portion from being damaged and to reduce the size of the restriction portion. The fluidity of the lubricating oil between the carrier and the external gear can be improved.

  An eccentric speed reducer according to a second aspect of the invention is the eccentric speed reducer according to the first aspect, wherein the carrier is a base carrier that rotatably holds one end side of the crankshaft via the crankshaft bearing, and the crank. An end carrier that rotatably supports the other end side of the shaft via the crankshaft bearing, and the base carrier and the end carrier are between the base carrier and the end carrier. A first external gear and a second external gear are provided as the external gears, and the first external teeth are formed on the base carrier as the plurality of protrusions. A plurality of base-side protrusions that contact the gear, and a plurality of end-side protrusions that are formed on the end carrier and contact the second external gear. The base side protrusion is A portion for the plurality of end-side protrusion in the second external gear abutting portion, characterized in that it is formed in a plane.

  According to the present invention, the base carrier is formed with a plurality of base side protrusions that contact the first external gear, and the end carrier is formed with a plurality of end side protrusions that contact the second external gear. . For this reason, it is possible to suppress the occurrence of damage to the plurality of base-side protrusions and the plurality of end-side protrusions, and to reduce the size of these protrusions. The lubricating oil between the base carrier and the first external gear And the fluidity of the lubricating oil between the end carrier and the second external gear can be improved.

  An eccentric speed reducer according to a third aspect of the invention is the eccentric speed reducer according to the second aspect of the invention, wherein the plurality of base side projections and the plurality of end side projections are arranged on the outer side of the carrier in the radial direction than the support column. It is characterized by being.

  According to the present invention, since the plurality of base side protrusions and the plurality of end side protrusions are arranged outside the support in the radial direction of the carrier, the protrusions can be easily processed using a lathe. In addition, when the protrusion is formed on the inner side in the radial direction from the support column, an expensive facility such as an end mill is required, resulting in an increase in manufacturing facility cost. In addition, since the plurality of base side protrusions and the plurality of end side protrusions are provided on the outer peripheral side portion of the carrier, the protrusions come into contact with the outer peripheral side portion of the external gear. As a result, the external gear can be supported more stably with respect to the carrier, and a support structure that can easily maintain the posture of the external gear by reducing the inclination of the external gear in the axial gap is realized. be able to.

  In the third aspect of the invention, the plurality of base side protrusions and the plurality of end side protrusions are further disposed between the support pillars in the circumferential direction of the carrier, and are arranged outside the support in the radial direction of the carrier. It is desirable that A corner R portion (a portion formed on a curved surface as a built-up portion of the corner portion) is required at the corner portion at the base portion connected to the carrier of the support column in order to reduce stress concentration. However, the plurality of base-side protrusions and the plurality of end-side protrusions are arranged on the outer periphery between the columns, so that interference with the corner R portion can be prevented and the plurality of protrusions can be arranged in a space efficient manner.

  An eccentric speed reducer according to a fourth aspect of the present invention is the eccentric speed reducer according to any one of the first to third aspects, wherein the plurality of protrusions are formed on the carrier and rotatably hold the crankshaft. It arrange | positions around the holding | maintenance part, It is characterized by the above-mentioned.

  According to the present invention, since the plurality of protrusions are arranged around the crank holding portion, the external gear is supported by the plurality of protrusions at a position in the vicinity of the crankshaft near the position where the external force acts from the crankshaft in the external gear. The inclination of the external gear in the axial gap can be reduced, and the occurrence of uneven contact of the roller member in the crankshaft bearing can be suppressed.

  According to the present invention, in the eccentric type reduction gear provided with the restriction portion for restricting the position of the external gear with respect to the carrier, the restriction portion can be prevented from being damaged and the restriction portion can be reduced in size. The fluidity of the lubricating oil between the gear and the external gear can be improved.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The eccentric speed reducer according to the embodiment of the present invention can be widely applied to various industrial machines such as industrial robots and various machine tools, construction machines, and the like. For example, in a windmill, since the diameter of a blade (blade) tends to increase in recent years, yaw driving that is a driving device for swinging to turn the nacelle of the windmill in accordance with the wind direction. As a device, a reduction gear with a high output specification (large load capacity) is required while suppressing an increase in size. For this reason, the eccentric type reduction gear according to the present embodiment is preferably used as a yaw drive device for a windmill. In addition to this example, the external gear meshing with the pin internal teeth rotates eccentrically with the rotation of the crankshaft in the case, and the position of the external gear relative to the carrier that rotatably holds the crankshaft is restricted. As for the eccentric type reduction gear to be used, it can be widely applied.

  FIG. 1 is a cross-sectional view showing an eccentric speed reducer 1 according to an embodiment of the present invention. The eccentric speed reducer 1 is used, for example, as a windmill yaw drive device for turning a nacelle of a windmill, and decelerates, transmits, and outputs the rotation input from the motor 100 disposed on the upper side. The eccentric speed reducer 1 includes a case 11, a pin internal tooth 22, a front speed reduction part 12, a rear speed reduction part 13, an output shaft 14, and the like.

  As shown in FIG. 1, the eccentric speed reducer 1 has a pinion 101 attached to an output shaft 14 positioned so as to protrude from the case 11 on one end side disposed on the lower side, and the other end side disposed on the upper side. The motor 100 is attached to the case 11. In the eccentric speed reducer 1, the rotational force input from the motor 100 disposed on the upper side is decelerated and transmitted via the front speed reducer 12 and the rear speed reducer 13 disposed in the case 11 and output. Output to the pinion 101 attached to the shaft 14. When the eccentric speed reducer 1 is used as a windmill yaw drive device, the eccentric speed reducer 1 is arranged so that the pinion 101 meshes with a gear fixed to the top of the tower of the windmill. And the eccentric type reduction gear 1 act | operates with the drive force from the motor 100, and the pinion 101 rotates, and the nacelle of a windmill turns. In FIG. 1 and FIG. 2 to be described later, the rotation center line P of the eccentric speed reducer 1 is indicated by a one-dot chain line, and a cross section shown on the left side and a cross section shown on the right side with respect to the rotation center line P. Cross sections at different angles in the circumferential direction (circumferential direction around the rotation center line P) are shown. In the following description, in the eccentric reduction gear 1, the lower output side where the output shaft 14 is disposed is one end side, and the upper input side where the motor 100 is disposed is the other end side. explain.

  As shown in FIG. 1, the case 11 of the eccentric speed reducer 1 includes a cylindrical first case portion 11a and a second case portion 11b arranged on the other end side of the first case portion 11a. The edges are connected with bolts. The case 11 accommodates a front-stage reduction unit 12, a rear-stage reduction unit 13, and the like. The front-stage reduction unit 12, the rear-stage reduction unit 13, and the output shaft 14 have a rotation center line P (see FIG. 1). In FIG. 1, they are arranged in series along an axial direction which is a direction indicated by a one-dot chain line. The case 11 has an opening at one end (the end of the first case 11a), and the motor 100 is fixed to the other end (the end of the second case 11b) as described above. In addition, an oil supply port for supplying lubricating oil into the case 11 and an oil discharge port for discharging the lubricating oil sealed in the case 11 are provided at predetermined locations in the case 11. Lubricating oil can be supplied or replaced inside.

  FIG. 2 is an enlarged cross-sectional view showing the rear-stage deceleration unit 13 and its vicinity in FIG. As shown in FIG. 1 and FIG. 2, a plurality of pin inner teeth 22 are provided, and are fitted into a pin groove 52 formed on the inner periphery of the first case portion 11 a to be attached to the inside of the case 11. It is arranged around the circumference. Pin internal teeth 22 (in FIG. 1 and FIG. 2, the external shape is shown in cross section) are formed as pin-shaped members (round bar-shaped members), and are arranged so that their longitudinal directions are parallel to the rotation center line P. In addition, they are arranged at equal intervals along the circumferential direction on the inner periphery of the case 11 and are configured to mesh with external teeth 31 of an external gear 28 described later.

  As shown in FIG. 1, the front speed reduction unit 12 includes a one-stage planetary gear mechanism to which the rotational driving force from the motor 100 is transmitted and an input gear 15, and the planetary gear mechanism is a planetary carrier 16. The planetary gear 17 and the ring gear 18 are provided. A plurality of planetary gears 17 are arranged around the rotation shaft 100a of the motor 100 disposed so as to protrude toward the inside of the case 11, and mesh with a gear formed on one end side of the rotation shaft 100a. In contrast, the eccentric speed reducer 1 is positioned in the radial direction (perpendicular to the rotation center line P). The planet carrier 16 is formed as a planetary frame that rotatably holds the plurality of planetary gears 17 at positions of equal angles along the circumferential direction around the rotation shaft 100a and performs a revolving operation. The ring gear 18 is provided as a ring-shaped gear having teeth formed on the inner periphery and meshing with the planetary gear 17, and is fixed to a portion formed so as to project inward from a plurality of locations in the second case portion 11b. ing.

  As shown in FIGS. 1 and 2, the input gear 15 is provided as a shaft-shaped gear member and is disposed on the rotation center line P. The input gear 15 is formed with a gear portion 15 a that meshes with a spur gear 49 described later on one end side, and a spline that is connected to the inner peripheral portion of the planet carrier 16 on the other end side. As a result, the input gear 15 is configured to input to the spur gear 49 the rotational driving force from the rotating shaft 100a that is decelerated and transmitted via the planetary gear 17, the ring gear 18, and the planet carrier 16.

  As shown in FIG. 1 and FIG. 2, the rear speed reduction unit 13 includes a spur gear 49, a crankshaft 23, a base carrier 25, an end carrier 26, a support 27, an external gear 28, a crankshaft bearing (34, 35), an outer A tooth bearing (53, 54), a restricting portion (55, 56) and the like are provided.

  A plurality of spur gears 49 shown in FIGS. 1 and 2 (four in this embodiment) are arranged around the input gear 15 so as to mesh with the gear portion 15 a of the input gear 15, and are eccentric with respect to the input gear 15. It is located in the radial direction of the mold speed reducer 1. The spur gear 49 is formed with a through hole in the central portion, and is fixed to the other end side of the crankshaft 23 by spline coupling in the through hole.

  A plurality of crankshafts 23 shown in FIGS. 1 and 2 (four in the present embodiment) are arranged at equal angular positions along the circumferential direction around the rotation center line P. The direction of the line Q) is arranged to be parallel to the rotation center line P. Each crankshaft 23 (in FIG. 1 and FIG. 2, the outer shape is shown not in cross section) is disposed so as to penetrate through each of the crank holes 30 formed in the external gear 28, and rotates to external teeth. It is provided as a shaft member that rotates the gear 28 eccentrically. And the crankshaft 23 will perform a revolution operation | movement with rotation of the external gear accompanying self rotation (autorotation).

  Further, the crankshaft 23 is formed with a first eccentric portion 23a, a second eccentric portion 23b, a first shaft portion 23c, and a second shaft portion 23d, and the first shaft portion 23c and the first eccentric portion are formed from one end side. 23a, the second eccentric portion 23b, and the second shaft portion 23d are provided in series in this order. The 1st eccentric part 23a and the 2nd eccentric part 23b comprise the eccentric part of this embodiment. The first eccentric portion 23a and the second eccentric portion 23b are formed such that a cross section perpendicular to the axial direction is a circular cross section, and each center position is provided to be eccentric with respect to the rotation center line Q of the crankshaft 23. It has been. The first eccentric portion 23 a and the second eccentric portion 23 b are disposed in the crank hole 30 of the external gear 28.

  A first shaft portion 23c provided on one end side of the crankshaft 23 is rotatably held with respect to the base carrier 25 via a first crankshaft bearing 34 configured as a roller bearing. A second shaft portion 23d provided on the other end side of the crankshaft 23 is rotatably held with respect to the end carrier 26 via a second crankshaft bearing 35 configured as a roller bearing. In addition, the 1st crankshaft bearing 34 and the 2nd crankshaft bearing 35 comprise the crankshaft bearing of this embodiment. Further, as described above, the spur gear 49 is fixed to the second shaft portion 23d at the end portion thereof so as to protrude from the second crankshaft bearing 35 to the other end side.

  As shown in FIGS. 1 and 2, the external gear 28 is accommodated in the case 11, and the external gear 28 includes a first external gear 28 a arranged in parallel in the case 11 and a first gear. Two external gears 28b are provided. The first external gear 28a and the second external gear 28b are respectively formed with a crank hole 30 through which the crankshaft 23 passes and a column through hole 48 through which the column 27 passes. The first external gear 28a and the second external gear 28b are arranged so that the positions of the crank hole 30 and the column through hole 48 correspond to each other in the direction parallel to the rotation center line P. The crank holes 30 of the first external gear 28a and the second external gear 28b are formed as circular holes, and correspond to the crankshaft 23 in the circumferential direction of the first external gear 28a and the second external gear 28b. A plurality of (four in the present embodiment) are arranged at equal angular positions. The first eccentric portion 23a is disposed in the crank hole 30 of the first external gear 28a, and the second eccentric portion 23b is disposed in the crank hole 30 of the second external gear 28b. The column through holes 48 are formed as holes corresponding to the cross-sectional shape of the column 27, and a plurality (four in this embodiment) are arranged at equal angle positions along the circumferential direction of the external gear 28 corresponding to the columns 27. Has been. Moreover, the support | pillar through-hole 48 is alternately formed with the hole 30 for cranks in the circumferential direction of the 1st external gear 28a and the 2nd external gear 28b. In addition, the support | pillar 27 has penetrated the support | pillar through-hole 48 in the loose-fit state.

  In addition, external teeth 31 that mesh with the pin internal teeth 22 are provided on the outer circumferences of the first external gear 28a and the second external gear 28b. In the present embodiment, the number of teeth of the external teeth 31 of the first external gear 28 a and the second external gear 28 b is provided to be one less than the number of teeth of the pin internal teeth 22. For this reason, each time the crankshaft 23 rotates, the meshing between the meshing external teeth 31 and the pin internal teeth 22 is shifted, and the external gears 28 (28a, 28b) are eccentrically rotated. The difference in the number of teeth between the external teeth 31 and the pin internal teeth 22 may be plural.

  As shown in FIG. 2, the first external gear bearing 53 rotates the first eccentric portion 23a of the crankshaft 23 with respect to the first external gear 28a in the crank hole 30 of the first external gear 28a. It is provided as a bearing that can be freely held. The first external tooth bearing 53 includes a plurality of roller members 53a configured as needle roller members or cylindrical roller members. The second external tooth bearing 54 is a bearing that rotatably holds the second eccentric portion 23b of the crankshaft 23 with respect to the second external gear 28b in the crank hole 30 of the second external gear 28b. Is provided. Similar to the first external tooth bearing 53, the second external tooth bearing 54 includes a plurality of roller members 54 a configured as needle roller members or cylindrical roller members. The first external tooth bearing 53 and the second external tooth bearing 54 constitute the external tooth bearing of this embodiment.

  As shown in FIGS. 1 and 2, one end side and the other end side of the crankshaft 23 are rotatably held via crankshaft bearings (34, 35), and the base carrier is used as a carrier to which the output shaft 14 is fixed. 25 and end carrier 26 are provided. The base carrier 25 has the output shaft 14 integrally formed at one end side thereof and is disposed in the case 11 (the output shaft 14 is integrally formed and fixed to the base carrier 25). The base carrier 25 is formed with a crank holding hole 50 on the other end side, and the crank holding hole 50 allows one end side of each crankshaft 23 to freely rotate at the first shaft portion 23c via the first crankshaft bearing 34. Hold on. The crank holding hole 50 is formed at a position of an equal angle along the circumferential direction around the rotation center line P. Further, the base carrier 25 is rotatably held on the outer peripheral side with respect to the inner peripheral side of the first case portion 11a via the roller bearing 36. A positioning member 44 provided as a ring-shaped member disposed along the outer periphery of the base carrier 25 is fixed. The roller bearing 36 is positioned with one end side engaged with the positioning member 44 and the other end side engaged with one end side of the first case portion 11a. A plurality of seals 59 are arranged between the outer periphery of the base carrier 25 and the inner periphery of the case 11 and are sealed so that the lubricating oil in the case 11 does not leak to the outside.

  As shown in FIGS. 1 and 2, the end carrier 26 is connected to the base carrier 25 via a support column 27 and is provided as a disk-shaped member. The end carrier 26 is rotatably held with respect to the inner peripheral side of the case 11 via a ball bearing 37 on the outer peripheral side thereof. The ball bearing 37 has one end engaged with the other end of the first case 11 a of the case 11, and the other end engaged with the edge 26 a protruding in a flange shape on the other end of the end carrier 26. It is arranged in the state. Further, the end carrier 26 has a crank through hole as a through hole in which the second shaft portion 23d on the other end side of the crank shaft 23 is disposed at a position at an equal angle along the circumferential direction centering on the rotation center line P. 43 is formed. In the crank through-hole 43, the other end side of the crankshaft 23 is rotatably held by the second shaft portion 23d via the second crankshaft bearing 35.

  As shown in FIGS. 1 and 2, the column 27 is disposed between the base carrier 25 and the end carrier 26 and is provided as a columnar portion that connects the base carrier 25 and the end carrier 26. A plurality (four in the present embodiment) of the support columns 27 are arranged at equal angular positions along the circumferential direction around the rotation center line P, and are arranged so that the axial directions thereof are parallel to the rotation center line P. ing. In addition, the support | pillar 27 and the crankshaft 23 are alternately arrange | positioned along the circumferential direction centering on the rotation centerline P. As shown in FIG. Each support column 27 is formed integrally with the base carrier 25 and is provided so as to protrude on the other end side of the base carrier 25. Each strut 27 is formed with a plurality of strut pin holes 51 that open to the other end of the end carrier 26 and extend to the strut 27 and into which a round rod-like (columnar) strut pin 40 is press-fitted. . As the support pins 40 are press-fitted into the support pin holes 51, the circumferential positions of the base carrier 25 and the end carrier 26 are matched.

  Each column 27 has one column bolt hole 47 that opens to the other end side of the end carrier 26 and extends to the base carrier 25 and into which a column bolt 29 indicated by a broken line in FIGS. 1 and 2 is inserted. Is formed. An internal thread portion is formed on the back side of the support bolt hole 47. The column bolt 29 has a screw portion formed as a male screw portion on one end side and a head portion on which the hexagonal hole for tightening is provided on the other end side. The column bolt 29 is configured to couple the end carrier 26 and the base carrier 25 via the column 27 by screwing the screw portion with the female screw portion of the column bolt hole 47. When the base carrier 25 and the end carrier 26 are connected by the coupling with the support bolts 29, the positioning member 44 fixed to the base carrier 25 and the end carrier 26 are brought into contact with the roller bearing 36 by the tightening force generated at that time. And the case 11 is clamped via the ball bearing 37 (held so as to be clamped). By this clamping, the base carrier 25 and the end carrier 26 are held rotatably with respect to the case 11.

  FIG. 3 is a plan view of the base carrier 25 as viewed from the upper side which is the other end side. 4 is an enlarged view (FIG. 4 (a)) showing a part of the base carrier 25 as seen from the direction of arrow A in FIG. 3, and a cross section taken along line B in FIG. The expanded sectional view (Drawing 4 (b)) shown in a part notch state is shown. As shown in FIGS. 1 to 4, the restricting portions (55, 56) are formed on the carrier (25, 26), protrude toward the external gear 28 and abut against the external gear 28. It is formed as a plurality of protrusions (55a, 56a). The restriction portions (55, 56) are configured to restrict the position of the external gear 28 in the axial direction (axial direction of the external gear 28) with respect to the carrier (25, 26) by contacting the external gear 28. Has been. In addition, as the plurality of protrusions (55a, 56a), a plurality of base side protrusions 55a and a plurality of end portion side protrusions 56a are provided. The plurality of base side protrusions 55a are formed on the base carrier 25 and provided so as to abut one end side of the first external gear 28a. The plurality of end-side protrusions 56a are formed on the end carrier 26 so as to be in contact with the other end side of the second external gear 28b. A curved surface portion 57 is formed on the side surface portion of the plurality of base side protrusions 55a that is continuous with the base carrier 25, and the side surface portion of the plurality of end portion side protrusions 56a that is continuous with the end carrier 26 is also curved. A curved surface portion having the same configuration as that of the portion 57 is formed.

  Also, the plurality of protrusions (55a, 56a) shown in FIGS. 1 to 4 are distributed and arranged along the circumferential direction of the carrier (25, 26). In FIG. 3, the plurality of base side protrusions 55a distributed in the base carrier 25 are illustrated, but the plurality of base side protrusions 55a and the plurality of end side protrusions 56a are arranged in the circumferential direction of the carrier (25, 26). It arrange | positions at the position of an equal angle, respectively, and is each arrange | positioned rather than the support | pillar 27 in the radial direction outer side in a carrier (25, 26). Further, the plurality of base-side protrusions 55a and the plurality of end-side protrusions 56a are disposed between the support pillars 27 in the circumferential direction of the carrier (25, 26), and are more radial in the carrier (25, 26) than the support pillar 27. Arranged outside. Further, the plurality of base side protrusions 55 a are arranged around a crank holding hole 50 that is a crank holding portion that is formed on the base carrier 25 and holds one end side of the crankshaft 23. The plurality of end-side protrusions 56 a are arranged around the crank through hole 43 that is a crank holding portion that is formed on the end carrier 26 and holds the other end side of the crankshaft 23.

  Further, as well shown in FIG. 2, a portion of the external gear 28 with which the plurality of protrusions (55a, 56a) abuts is formed in a plane. That is, the contact surface 58a, which is a portion on one end side where the plurality of base side protrusions 55a abut on the first external gear 28a, is formed into a flat surface, and the plurality of end side protrusions 56a in the second external gear 28b. The abutting surface 58b which is the other end side portion on which the abuts is also formed in a flat surface. Note that the first external gear 28a and the second external gear 28b facing each other are also in contact with each other and their positions relative to each other are regulated.

  Next, the operation of the above-described eccentric speed reducer 1 will be described. The eccentric speed reducer 1 operates when the motor 100 is operated. When the operation of the motor 100 is started, the planetary gear 17 connected to the rotating shaft 100a rotates and revolves while meshing with the ring gear 18, whereby the planetary carrier 16 rotates and is connected to the planetary carrier 16. The input gear 15 rotates. When the input gear 15 rotates, each spur gear 49 that meshes with the input gear 15 rotates, and the first eccentric portion 23a and the second eccentric portion 23b rotate together with each crankshaft 23 to which each spur gear 49 is fixed. Along with this rotation, a load acts on the external gear 28 (28a, 28b) from the first and second eccentric portions (23a, 23b), and the external gear 28 (28a, 82b) is pin internal teeth 22. And rotate eccentrically so as to swing while shifting the mesh. As the external gear 28 (28a, 28b) rotates eccentrically, the first external gear bearing 53 uses the second external gear bearing 54 as the second external gear 28b. On the other hand, each of the crankshafts 23 which are held in rotation performs a revolution operation around the rotation center line P. By the revolving operation of the crankshaft 23, the output shaft 14 rotates together with the base carrier 25 and the end carrier 26 that are connected by the support column 27 and rotatably hold the crankshaft 23, and a large torque is output from the pinion 101. It will be.

  Further, during the operation described above, the lubricating oil flows in the case 11 with the operations of the crankshaft 23, the base carrier 25, the end carrier 26, the external gear 28, and the like. Then, between the base carrier 25 and the first external gear 28a, the lubricating oil flows between the plurality of base side protrusions 55a and flows. On the other hand, also between the end carrier 26 and the second external gear 28b, the lubricating oil flows between the plurality of end side projections 56a and flows. Accordingly, sufficient lubricating oil is circulated and supplied to the first crankshaft bearing 34, the second crankshaft bearing 35, the first external tooth bearing 53, and the second external tooth bearing 54.

  When the eccentric speed reducer 1 is used as a yaw drive device, a load acting in the vertical direction is efficiently supported by a plurality of protrusions (55a, 56b) extending in the vertical direction and contacting the external gear 28. Will be. Further, since the restriction portions (55, 56) for restricting the axial position of the external gear 28 are formed in the carrier (25, 26), the rotational operation of the external gear 28 is stabilized, and the external gear is stabilized. The durability of 28 is also improved.

  According to the eccentric type reduction gear 1 described above, the restriction portions (55, 56) formed on the carrier (25, 26) and restricting the axial position of the external gear 28 with respect to the carrier (25, 26) are the carrier. A plurality of protrusions (55a, 56a) that are distributed along the circumferential direction of (25, 26) and abut against the external gear 28 are formed. For this reason, the lubricating oil in the case 11 flows between the protrusions 55a and the protrusions 56a, and the fluidity of the lubricating oil between the carriers (25, 26) and the external gear 28 can be improved. . And, by improving the fluidity, the lubricating oil in the case 11 is efficiently circulated and supplied to the crankshaft bearings (34, 35) and the external tooth bearings (53, 54), and the crankshaft bearings (34, 35). Also, the lubricity of the external tooth bearings (53, 54) can be improved. In addition, since the plurality of protrusions (55a, 56a) are formed on the carrier (25, 26), the carrier-side protrusions (55a, 56a) are compared to the case where the restriction portions are provided between the external gears (28a, 28b). ) And the external gear 28 can be reduced, and the protrusions (55a, 56a) can be formed small to reduce the size of the restricting portion (55, 56). In addition, since the contact surfaces (58a, 58b), which are portions where the protrusions (55a, 56a) abut on the external gear 28, are formed in a flat surface, the protrusions (55a, 56a) do not slide with each other in the first place, and it is also possible to prevent the occurrence of damage such as scraping the mating projections (55a, 56a) at the corners of the projections (55a, 56a). Therefore, the protrusions (55a, 56a) can be further reduced, and the fluidity of the lubricating oil between the carrier (25, 26) and the external gear 28 can be enhanced.

  Therefore, according to the present embodiment, in the eccentric speed reducer 1 provided with the restriction portion (55, 56) for restricting the position of the external gear 28 with respect to the carrier (25, 26), the restriction portion (55, 56) It is possible to suppress the occurrence of damage and to reduce the size of the restricting portions (55, 56), and to improve the fluidity of the lubricating oil between the carrier (25, 26) and the external gear 28. .

  Further, according to the eccentric speed reducer 1, the base carrier 25 has a plurality of base-side protrusions 55a that abut on the first external gear 28a, and the end carrier 26 has a plurality of ends that abut on the second external gear 28b. Part-side protrusions 56b are respectively formed. For this reason, it is possible to suppress the occurrence of damage to the plurality of base-side protrusions 55a and the plurality of end-side protrusions 56a, and to reduce the size of these protrusions (55a, 56a). Both the fluidity of the lubricating oil between the toothed gear 28a and the fluidity of the lubricating oil between the end carrier 26 and the second external geared 28b can be improved.

  Further, according to the eccentric speed reducer 1, the plurality of base-side projections 55 a and the plurality of end-side projections 56 a are arranged on the outer side in the radial direction of the carrier (25, 26) rather than the support column 27. For this reason, it is easy to use a lathe without requiring an expensive equipment such as an end mill as in the case where a protrusion is formed on the inner side in the radial direction from the support column 27 and causing an increase in manufacturing equipment cost. The protrusions (55a, 56a) can be processed. Further, since the plurality of base side protrusions 55a and the plurality of end side protrusions 56a are provided on the outer peripheral side portion of the carrier (25, 26), the protrusions (55a, 56a) will come into contact. As a result, the external gear 28 can be more stably supported with respect to the carrier (25, 26), and the inclination of the external gear 28 in the axial gap can be reduced to further improve the posture of the external gear 28. A support structure that is easy to hold can be realized. Note that the above-mentioned corner R portion is necessary at the corner portion of the base portion of the support column 27 connected to the carrier (25, 26) in order to alleviate stress concentration. However, according to the eccentric speed reducer 1, the plurality of base-side protrusions 55a and the plurality of end-side protrusions 56a are arranged on the outer periphery between the columns 27, thereby preventing interference with the corner R portion and space efficiency. A plurality of protrusions (55a, 56a) can be arranged well.

  Further, according to the eccentric type reduction gear 1, the plurality of protrusions (55 a, 56 a) are disposed around the crank holding hole 50 and the crank through hole 43 that are the crank holding portions, respectively. The external gear 28 can be supported by a plurality of protrusions (55a, 56a) at a position in the vicinity of the crankshaft 23 that is close to the position where the external force is applied from 23. Thereby, the inclination in the clearance in the axial direction of the external gear 28 can be reduced, and occurrence of uneven contact of the roller member in the crankshaft bearing (34, 35) can be suppressed.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. For example, the present invention may be applied to a center crank type eccentric speed reducer in which a crankshaft is disposed on a rotation center line. Further, the output shaft may not be integrated with the carrier but may be provided as a separate member from the carrier. Moreover, the support | pillar which connects a base carrier and an edge part carrier does not need to be integrally formed in a base carrier, and may be formed as a member different from a carrier. Also, the number of crankshafts and struts may be three or less or five or more. Further, the number of eccentric parts of the crankshaft and the number of external gears need not be two. Further, both the base-side protrusion and the end-side protrusion may not be provided as the plurality of protrusions, and only one of them may be provided. The plurality of protrusions are not limited to those illustrated in the present embodiment, and the shape, number, and position can be variously changed.

  The present invention provides an eccentric type in which an external gear meshing with a pin internal tooth rotates eccentrically with the rotation of the crankshaft and the position of the external gear with respect to a carrier that rotatably holds the crankshaft is regulated in the case. As a reduction gear, it can be widely applied.

It is sectional drawing of the eccentric type reduction gear in one embodiment of this invention. It is sectional drawing which expands and shows the back | latter stage deceleration part and its vicinity of the eccentric type reduction gear shown in FIG. It is a top view of the base carrier of the eccentric type reduction gear shown in FIG. FIG. 4 is an enlarged view showing a part of the base carrier as viewed from the direction of arrow A in FIG. 3 in a notched state, and an enlarged sectional view showing the section along the line B in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Eccentric reducer 11 Case 14 Output shaft 22 Pin internal tooth 23 Crankshaft 25 Base carrier 26 End carrier 28, 28a, 28b External gear 30 Crank hole 31 External tooth 34, 35 Crankshaft bearing 53, 54 External tooth Bearings 55, 56 Restricting portions 55a, 56a Plural protrusions 101 Pinion

Claims (2)

Case and
A plurality of pin internal teeth disposed on the inner periphery of the case and formed as a pin-shaped member;
An external gear that is housed in the case and has external teeth that engage with the pin internal teeth on the outer periphery;
A crankshaft that passes through a hole for a crank formed in the external gear and rotates the external gear eccentrically by rotating;
An eccentric portion formed on the crankshaft, disposed in the hole for the crank and provided eccentric to the rotation center line of the crankshaft;
An external tooth bearing that rotatably holds the eccentric portion with respect to the external gear in the crank hole;
A carrier that rotatably holds one end side and the other end side of the crankshaft via a crankshaft bearing;
An output shaft fixed to the carrier and to which a pinion is attached;
A restricting portion that is formed on the carrier and abuts on the external gear to restrict the position of the external gear relative to the carrier in the axial direction;
An eccentric speed reducer with
The restricting portion is formed as a plurality of protrusions that protrude toward the external gear and abut against the external gear,
The plurality of protrusions are provided so as to be distributed along the circumferential direction of the carrier,
In the external gear, the portion where the plurality of protrusions abut is formed in a flat surface. The eccentric speed reducer according to claim 1,
As the carrier, a base carrier that rotatably holds one end side of the crankshaft via the crankshaft bearing, and an end carrier that rotatably holds the other end side of the crankshaft via the crankshaft bearing. And the base carrier and the end carrier are connected via a post disposed between the base carrier and the end carrier,
As the external gear, a first external gear and a second external gear are provided,
As the plurality of protrusions, a plurality of base-side protrusions formed on the base carrier and abutting on the first external gear, and a plurality of ends formed on the end carrier and abutting on the second external gear Side protrusions, and
A portion where the plurality of base side protrusions abut on the first external gear and a portion where the plurality of end side protrusions abut on the second external gear are formed in a plane. Eccentric reducer.

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