JP2007056885A - Revolution support structure of carrier in planetary gear reducer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide revolution support structure of a carrier, which can reduce the radial size, and improve the durability of a revolution support of the carrier for a casing in a planetary gear reducer. <P>SOLUTION: The carrier 7 is provided with an opening 7b to store a planetary gear 5, and a through hole 7k in which a connection pin 8 is inserted into one peripheral wall 7f along the axial direction of the carrier 7 in the axial direction of the opening 7b. The carrier 7 is also provided with a cylindrical body 25 in which a peripheral wall 7k is reduced in the outside diameter inwardly from the position of the through hole 7k, and a recess groove 7h containing at least a cross sectional surface of the through hole 7k is formed in the outer periphery of the diameter reducing portion 7s axially outside of the connection pin 8 to cover the diameter reducing portion 7s, and a bearing 21 engaged with the outer periphery of the cylindrical body 25 covering the diameter reducing portion 7s and supporting the carrier 7 via the cylindrical body 25. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rotation support structure for a carrier that rotatably supports a carrier with respect to a casing in a planetary gear speed reducer.

  Conventionally, in a planetary gear reducer, an input shaft that rotates in response to a driving force of a drive source, a sun gear that rotates together with the input shaft, and a sun gear that are coaxially arranged in the casing via a gap. An installed internal gear, a plurality of planetary gears disposed in the gap and meshing with the sun gear and the internal gear, and a carrier that rotatably supports the planetary gear and rotates coaxially with the sun gear. There is known a carrier rotation support structure in which a bearing (so-called bearing) is disposed between the outer periphery of the carrier and the inner periphery of the casing, and the carrier is rotatably supported via the bearing. Yes.

Further, in the planetary gear speed reducer, the carrier is provided with an opening for storing the planetary gear, and through holes through which connecting pins for supporting the planetary gear are inserted may be provided on both axial walls of the opening. In some cases, bearings are mounted between the outer periphery of the carrier and the inner periphery of the casing on both sides in the axial direction via the connecting pin (see, for example, Patent Documents 1 and 2).
JP 2003-172411 A Japanese Patent Laid-Open No. 2005-009614

  According to the rotation support structure of the carrier in the planetary gear speed reducer described in the conventional example, if the outer diameter of the carrier with which the bearing engages is made to overlap with the through hole through which the connecting pin of the planetary gear is inserted, this carrier A notch in which a through hole extends on the outer periphery of the bearing is generated, and as a result, the carrier cannot be supported by the entire inner periphery of the bearing, and the durability of the bearing and the outer periphery of the carrier with which the bearing engages may be impaired. Therefore, the carrier rotation support structure in the planetary gear speed reducer described in the conventional example is configured such that the bearing supports the carrier on the outer diameter side from the through hole, and it has been difficult to reduce the size.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a carrier rotation support structure for a planetary gear speed reducer that can reduce the size in the radial direction and improve the durability of the carrier rotation support portion.

  The invention according to claim 1, which has been made to achieve this object, is a carrier disposed in a casing and rotatably supporting a planetary gear via a connecting pin, and the carrier is rotatably supported. In the rotating support structure of the carrier in the planetary gear speed reducer provided with a casing to be provided, the carrier is provided with an opening portion for housing the planetary gear, and at least one peripheral wall in the axial direction of the opening portion, A through-hole through which the connecting pin is inserted along the axial direction of the carrier is provided, and the outer diameter of the peripheral wall is on the inner side of the position of the through-hole on the outer side in the axial direction than the connecting pin. The diameter is reduced, and a concave groove including at least the through hole is formed on the outer periphery of the reduced diameter portion. The cylindrical body covering the reduced diameter portion is engaged with the outer periphery of the cylindrical body. A shaft that supports the carrier via Characterized in that it comprises and.

  According to the rotating support structure of the carrier in the planetary gear speed reducer according to claim 1, the carrier has a through-hole through which the connecting pin is inserted in at least one peripheral wall in the axial direction of the opening that stores the planetary gear. And in the radial direction, the outer periphery of one peripheral wall is reduced inward from the position of the through hole, and a cylindrical body that covers the reduced diameter portion is engaged with the outer periphery of the cylindrical body. Since the bearing for supporting the carrier is provided, the size in the radial direction can be reduced, and the durability of the rotation support portion of the carrier with respect to the casing can be improved.

  That is, according to the rotation support structure of the carrier in the planetary gear speed reducer according to claim 1, the cylindrical shape is formed even if the inner diameter of the bearing is positioned to overlap the through hole through which the support pin supporting the planetary gear is inserted. The carrier can be supported on the entire inner circumference of the bearing through the body, and the durability of the bearing and the outer circumference of the carrier with which the bearing engages can be improved. As a result, the diameter of the bearing in the radial direction can be improved. However, there is no restriction on the position of the through-hole, and the size can be easily reduced.

  Further, according to the rotating support structure of the carrier in the planetary gear speed reducer according to claim 1, since the bearing is engaged with the carrier via the cylindrical body, the cylindrical body can be replaced if necessary. It is possible to easily change the material of the cylindrical body. Further, in the planetary gear speed reducer according to claim 1, the rotation support structure of the carrier 7 includes a concave groove formed between the cylindrical body and the reduced diameter portion, so that the carrier is interposed via the cylindrical body. Can be supported flexibly, and the meshing of each gear can be made smooth.

  Further, in the planetary gear speed reducer according to claim 1, the carrier rotation support structure has a shaft on the inner periphery of the cylindrical body or the outer periphery of the reduced diameter portion, as in the invention of claim 2. A plurality of convex portions extending in the direction are formed along the circumferential direction, and the cylindrical member can be easily press-fitted into the carrier via the convex portions.

  Further, in the planetary gear reducer according to claim 1 or 2, the carrier rotation support structure according to the invention described in claim 3 is such that the bearing rotates between the inner ring and the outer ring via a rolling element. A plurality of convex portions extending in the axial direction are formed along the circumferential direction on the outer periphery of the cylindrical body, and the bearing is formed into the cylindrical body via the convex portions. Can be easily press-fitted.

  Further, in the planetary gear speed reducer according to any one of claims 1 to 3, the carrier support structure of the planetary gear reducer according to the invention according to claim 4, wherein the hardness of the cylindrical body is at least the carrier or By being lower than any one of the bearings, the carrier can be flexibly supported via the cylindrical body, and the meshing of the gears can be smoothly performed.

  Further, in the planetary gear speed reducer according to any one of claims 1 to 4, the carrier support structure for the planetary gear speed reducer is such that the cylindrical body is opposite to the connecting pin as in the invention according to claim 5. One end side located on the side protrudes from the end portion in the axial direction of the reduced diameter portion, and the other end side located on the connecting pin side is fixed to the reduced diameter portion. The carrier is supported like a cantilever and the carrier is flexibly supported by the casing via the cylindrical body, so that smooth meshing of each gear can be obtained.

  According to the rotation support structure of the carrier in the planetary gear speed reducer of the present invention, the carrier has a through hole through which the connecting pin is inserted in at least one peripheral wall in the axial direction of the opening that stores the planetary gear, and has a diameter. In the direction, the outer periphery of one peripheral wall is reduced inward from the position of the through hole, the cylindrical body covering the reduced diameter portion, the outer periphery of the cylindrical body is engaged, and the carrier is interposed via the cylindrical body. Since the size of the radial direction can be reduced, the durability of the rotation support portion of the carrier with respect to the casing can be improved.

  That is, according to the rotation support structure of the carrier in the planetary gear speed reducer of the present invention, the inner diameter of the bearing is set to a position overlapping the through hole through which the support pin supporting the planetary gear is inserted, and the carrier is interposed via the cylindrical body. The carrier can be supported by the entire inner circumference of the bearing, and the durability of the bearing and the outer circumference of the carrier with which the bearing engages can be improved. In the radial direction, the diameter of the bearing is constrained by the position of the through hole. Can be easily reduced in size. In addition, according to the rotating support structure of the carrier in the planetary gear speed reducer of the present invention, the bearing is engaged with the carrier via the cylindrical body, so that the cylindrical body can be replaced or the cylindrical body as necessary. The material of the shape can be easily changed.

  In the planetary gear speed reducer according to the present invention, the carrier support structure includes a plurality of convex portions extending in the axial direction on the inner periphery of the cylindrical body or the outer periphery of the reduced diameter portion along the circumferential direction. Therefore, the cylindrical body can be easily press-fitted into the reduced diameter portion of the carrier.

  In the planetary gear speed reducer according to the present invention, the carrier rotation support structure flexibly supports the carrier via the cylindrical body because the hardness of the cylindrical body is lower than at least one of the carrier and the bearing. It is possible to smoothly mesh the gears. Furthermore, in the planetary gear speed reducer according to the present invention, the carrier rotation support structure is such that the cylindrical body projects from the end in the axial direction of the reduced diameter portion on the side opposite to the connection pin, and is positioned on the connection pin side. By fixing the other end side to the reduced diameter portion, the cylindrical body is supported in a cantilever shape by the reduced diameter portion via the other end side, and the carrier can be flexibly supported via this cylindrical body. The meshing of each gear can be made smooth.

  Next, the rotation support structure of the carrier in the planetary gear speed reducer according to one embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view showing the structure of a planetary gear speed reducer to which the present invention is applied. 2A is a cross-sectional view of the carrier, FIG. 2B is an external view seen from the direction of arrow A in FIG. 2A, and FIG. 2C is an engagement of the planetary gear and the cylindrical body with the carrier. FIG. 6 is a cross-sectional view taken along line (d) of FIG. FIG. 3 is an external view showing the structure of the cylindrical body in the carrier rotation support structure of the embodiment, and (b) is a view as seen from the direction of arrow A in (a).

As shown in FIG. 1, the planetary gear speed reducer 1 is connected to an input shaft 2 that rotates by receiving a driving force of a drive motor (not shown) (so-called drive source) and the input shaft 2 connected to the input shaft 2. A sun gear 3 that rotates together with the sun gear 3, an internal gear 6 that is coaxially disposed in the sun gear 3 via a gap, a planetary gear 5 that is disposed in the gap and meshes with the sun gear 3 and the internal gear 6, and a connecting pin 8 The planetary gear 5 is rotatably supported through the carrier 7, and the carrier 7, the casings 9, 10, 11 and the oil seals 12, 13 are supported so as to be rotatable coaxially with the sun gear 3.

  In the planetary gear speed reducer 1, the casings 9, 10, 11 and the internal gear 6 are integrally fixed by bolts 14, 15, 16. Further, the casing 9 is provided with an engagement hole 9b and a screw hole 9c for fixing to a bracket of a drive motor (not shown). The opening 7b of the carrier 7 and the internal gear 6 are filled with a lubricant that lubricates the meshing of each gear. ,

  The input shaft 2 is inserted inside the casings 9 and 10 and is rotatably supported by the casing 9 and the casing 10 via a pair of bearings 17 and 18 arranged side by side in the axial direction. A biasing member 19 that biases the bearings 17 and 18 in the axial direction is mounted between the bearing 17 and the casing 9. The bearings 17 and 18 are provided with an outer ring and an inner ring coaxially via a spherical rolling element, and the outer periphery of the outer ring is fixed by being press-fitted into the inner wall of the casing 10, and the input shaft 2 is inserted through the inner ring.

  Further, the input shaft 2 is provided with a mounting hole 2c and a screw hole 2d for inserting and rotating a rotating shaft (not shown) of a drive motor, and the casing 9 is provided with a bolt tightening tool. A through hole 9a for insertion is provided.

  The sun gear 3 is fixed by press-fitting the shaft portion 3a and the gear outer diameter portion 3c on the base end side into the input shaft 2. Further, the sun gear 3 is provided with a shaft portion 3 b protruding from the tip side opposite to the base end side, and this shaft portion 3 b is rotatably engaged with an engagement hole 7 a formed in the carrier 7. Match.

  The planetary gear 5 is rotatably supported by the carrier 7 via the connection pin 8 and the bearing 20, with the connection pin 8 being rotatably engaged via the bearing 20. Further, both ends of the connecting pin 9 are supported by the peripheral walls 7 f and 7 g of the carrier 7.

  Next, the carrier 7 is provided with an opening 7b for housing the sun gear 3 and the planetary gear 5, and the shaft 7b of the sun gear 3 is rotatably engaged with the bottom wall of the opening hole 7b. A hole 7a is formed.

  Further, the carrier 7 includes through holes 7h and 7j through which the connecting pins 8 are inserted along the axial direction in the peripheral walls 7f and 7g on both sides in the axial direction of the opening 7b. Then, both ends of the connecting pin 8 are inserted into the through holes 7 h and 7 j, and the planetary gear 5 is supported via the connecting pin 8.

  Further, the carrier 7 is rotatably supported by the casing 10 and the casing 11 through a pair of bearings 21 and 22 that are separated from each other in the axial direction and face each other. The bearings 21 and 22 are constituted by spherical rolling elements 21a and 22a, inner rings 21b and 22b on which the rolling elements 21a and 21a roll, outer rings 21c and 22c, and the like (in this embodiment, as the bearings 21 and 22). Angular ball bearings are used.)

  Next, as shown in FIGS. 2A and 2B, the carrier 7 has an outer diameter that is smaller than the connecting pin 8 in the axial direction and the outer diameter of the peripheral wall 7 f is smaller than the position of the through hole 7 k. The reduced diameter portion 7s is provided. A concave groove 7h including a through hole 7k is formed on the outer periphery of the reduced diameter portion 7s so that the connecting pin 8 can be inserted into the through holes 7k and 7m along the arrow A direction. The concave grooves 7h are formed by the number of the planetary gears 5 and the circumferential positions thereof coincide with the positions of the planetary gears 5 and the connecting pins 8.

  2C and 2D, the cylindrical body 25 is press-fitted into the reduced diameter portion 7s of the carrier 7, and the inner ring 21b of the bearing 21 is press-fitted into the outer periphery of the cylindrical body 25. Has been. In addition, one end side of the cylindrical body 25 located on the side opposite to the connecting pin 8 protrudes from the axial end of the reduced diameter portion 7s, and the other end side positioned on the connecting pin 8 side is press-fitted into the reduced diameter portion 7s. Is fixed. That is, the cylindrical body 25 is supported in a cantilever shape by the reduced diameter portion 7s via the other end side.

  Further, as shown in FIG. 3, the cylindrical body 25 has a plurality of convex portions 25b extending in the axial direction on the inner periphery thereof along the circumferential direction, and the reduced diameter portion 7s via the convex portions 25b. It is press-fitted into. The cylindrical body 25 has a plurality of convex portions 25a extending in the axial direction on the outer periphery thereof, and the inner ring 21b of the bearing 21 is press-fitted through the convex portions 25a. Further, the cylindrical body 25 is made of molybdenum steel having excellent wear resistance, and is tempered so that its hardness is lower than the hardness of the carrier 7, and the plurality of through holes 25c are provided in the circumferential direction. The carriers 7 are arranged side by side so that the carrier 7 can be flexibly supported.

  In the planetary gear speed reducer 1 configured as described above, when the rotational driving force of the drive motor is transmitted via the input shaft 2, the sun gear 3 rotates together with the input shaft 2, and the planetary gears. 5 meshes with the sun gear 3 and the internal gear 6, revolves around the sun gear 3 and rotates around the connecting pin 8, and the carrier 7 rotates as the planetary gear 5 revolves. .

  Below, the effect of the rotation support structure of the carrier 7 in the planetary gear speed reducer 1 of the said Example is described.

  According to the rotating support structure of the carrier 7 in the planetary gear speed reducer 1 described in the present embodiment, the carrier 7 is connected to the one peripheral wall 7f in the axial direction of the opening 7b that houses the planetary gear 5 and the connecting pin 8 is provided. A cylindrical body 25 that includes a through-hole 7k to be inserted and whose outer circumference of one peripheral wall 7f is reduced inward from the position of the through-hole 7k in the radial direction and covers the reduced diameter portion 7s, and this cylindrical body 25 And the bearing 21 that supports the carrier via the cylindrical body, the radial size can be reduced, and the durability of the rotation support portion of the carrier 7 with respect to the casing 10 can be reduced. It can be improved.

  That is, according to the rotation support structure of the carrier 7 in the planetary gear speed reducer 1 of the present embodiment, the inner diameter of the bearing 21 is set to a position that overlaps the through hole 7k through which the connecting pin 8 that supports the planetary gear 5 is inserted. In addition, the carrier 7 can be supported by the entire inner periphery of the bearing 21 through the cylindrical body 25, and the durability of the bearing 21 and the reduced diameter portion 7s of the carrier 7 with which the bearing 21 engages can be improved. In the radial direction, the diameter of the bearing 21 is not restricted by the position of the through hole 7k, and the size can be easily reduced. Moreover, according to the rotation support structure of the carrier 7 in the planetary gear speed reducer 1 of the present invention, since the bearing 21 is engaged with the carrier via the cylindrical body 25, the bearing 21 is directly engaged with the carrier 7. Rather than doing this, the material of the engaging portion (the so-called material of the cylindrical body 25) can be easily changed as necessary.

  Further, in the planetary gear reducer 1 of the present embodiment, the rotation support structure of the carrier 7 is formed with a plurality of convex portions 25 a extending in the axial direction on the inner periphery of the cylindrical member 25 along the circumferential direction. The cylindrical body 25 can be easily press-fitted into the reduced diameter portion 7s of the carrier 7 through the convex portion 25a.

  Further, the rotation support structure of the carrier 7 in the planetary gear speed reducer 1 of the present embodiment is such that the hardness of the cylindrical body 25 is lower than the hardness of the carrier 7, so that the carrier 7 is flexible via the cylindrical body 25. Can support

  Further, one end of the cylindrical body 25 located on the side opposite to the connecting pin 8 protrudes from the axial end of the reduced diameter portion 7s, and the other end located on the connecting pin 8 side is press-fitted into the reduced diameter portion 7s. As a result, the cylindrical body 25 is supported in a cantilever shape by the reduced diameter portion 7s, and the carrier 7 can be flexibly supported via the cylindrical body 25 and the bearing 21, so that the gears can be smoothly engaged. . At this time, by arranging the bearing 21 from one end side of the cylindrical portion 25, an effect of flexibly supporting the carrier 7 can be exhibited.

  Furthermore, in the planetary gear speed reducer 1 according to the present embodiment, the rotation support structure of the carrier 7 includes a plurality of concave grooves 7h between the cylindrical body 25 and the reduced diameter portion 7S. The carrier 7 can be flexibly supported via 25 and the meshing of each gear can be made smooth.

  As mentioned above, although one Example of this invention was described, this invention is not limited to the said Example, It can take a various aspect.

  For example, in the rotation support structure of the carrier 7 of the planetary gear speed reducer 1 in the present embodiment, the convex portion 25a is formed on the cylindrical body in order to facilitate the press-fitting between the reduced diameter portion 7s of the carrier 7 and the cylindrical body 25. However, instead of forming the convex portions 25a on the cylindrical body 25, irregularities may be formed on the outer periphery of the reduced diameter portion 7s. Further, in the rotation support structure of the carrier 7 of the planetary gear speed reducer 1 according to the present embodiment, the cylindrical body 25 is provided with the through hole 25c in the shape of a long hole along the circumferential direction. A plurality may be arranged in parallel along the direction.

  Further, in the rotation support structure of the carrier 7 of the planetary gear speed reducer 1 in this embodiment, a ball bearing is used as the bearing 21, but a roller bearing is used instead of the ball bearing, and further, a taper roller bearing, a cross roller is used. It can also be applied by using a bearing or the like.

It is sectional drawing showing the structure of the planetary gear speed reducer of one Example to which this invention was applied. In the same example, (a) is a cross-sectional view of the carrier, (b) is an external view seen from the direction of arrow A of (a), (c) is a cross-sectional view in which the planetary gear and the cylindrical body are engaged with the carrier, (D) is the external view seen from the arrow A direction of (c). It is an external view showing the structure of the cylindrical body in the rotation support structure of the carrier of the Example, Comprising: (b) is the figure seen from the arrow A direction of (a).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Planetary gear reducer, 2 ... Input shaft, 2c ... Mounting hole, 2d ... Screw hole, 3 ... Sun gear, 3a, 3b ... Shaft part, 3c ... Gear outer diameter part, 5 ... Planetary gear, 6 ... Internal gear , 7 ... carrier, 7b ... opening, 7f, 7g ... peripheral wall, 7s ... reduced diameter part, 7k, 7m ... through hole, 7h ... concave groove, 8 ... connecting pin, 9, 10, 11 ... casing, 9a ... through Hole, 9b ... engagement hole, 9c ... screw hole, 12, 13 ... oil seal, 14, 15, 16 ... bolt, 17, 18 ... bearing, 19 ... biasing member, 20 ... bearing, 21, 22 ... bearing, 21a, 22a ... rolling elements, 21b, 22b ... inner ring, 21c, 22c ... outer ring, 25 ... cylindrical body, 25a, 25b ... convex part, 25c ... through hole.

Claims (5)

In a planetary gear reducer that is provided in a casing and includes a carrier that rotatably supports a planetary gear via a connecting pin, and a casing that rotatably supports the carrier.
The carrier includes
An opening for accommodating the planetary gear is provided, and at least one peripheral wall in the axial direction of the opening is provided with a through-hole through which the connecting pin is inserted along the axial direction of the carrier;
In addition, the outer diameter of the peripheral wall is reduced to the inner side of the position of the through hole on the outer side in the axial direction than the connecting pin, and the concave groove includes at least the through hole on the outer periphery of the reduced diameter portion. Formed,
A cylindrical body covering the reduced diameter portion;
A bearing that engages an outer periphery of the cylindrical body and supports the carrier via the cylindrical body;
With
A rotating support structure for a carrier in a planetary gear speed reducer. On the inner periphery of the cylindrical body or the outer periphery of the reduced diameter portion, a plurality of convex portions extending in the axial direction are formed along the circumferential direction,
The cylindrical body and the reduced diameter portion are press-fitted together via the convex portion,
The rotation support structure of the carrier in the planetary gear speed reducer according to claim 1. The bearing is supported so that the inner ring and the outer ring are rotatable via rolling elements,
On the outer periphery of the cylindrical body, a plurality of convex portions extending in the axial direction are formed along the circumferential direction,
The cylindrical body and the inner ring are press-fitted together through the convex portion,
The rotation support structure of the carrier in the planetary gear speed reducer according to claim 1 or 2.   4. The rotation support structure for a carrier in a planetary gear reducer according to claim 1, wherein the cylindrical body has a hardness lower than at least one of the carrier and the bearing. In the cylindrical body, one end side located on the side opposite to the connecting pin protrudes from the end portion in the axial direction of the reduced diameter portion, and the other end side positioned on the connecting pin side is fixed to the reduced diameter portion.
The carrier rotation support structure in the planetary gear reducer according to any one of claims 1 to 4, wherein the rotation support structure is a carrier.

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