JP2008249110A - Eccentric oscillating gear mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an eccentric oscillating gear mechanism which can surely form its central through-hole as large as possible with no deteriorating the strength of an oscillating body and a carrier. <P>SOLUTION: The eccentric oscillating gear mechanism EM1 of a speed reducing apparatus 112 comprises a driving eccentric body shaft 118 which is provided with an input gear 116, and integratedly rotates together with the input gear 116, the oscillating body 122 to be eccentrically oscillated by means of the driving eccentric body shaft 118, and carriers 126, 128 to be synchronized with the rotation component of the oscillating body 122. The center O3 of the through-hole 133 formed on the oscillating body 122 is shifted with respect to the center O1 of the oscillating body 122 by a shift amount δ1 in the radial direction (upward in the figure) opposite to the driving eccentric body shaft 118. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an eccentric oscillating gear mechanism.

  For example, Patent Document 1 discloses a reduction gear including an eccentric oscillating gear mechanism. FIGS. 7 to 9 show a speed reducer substantially the same as this speed reducer.

  The speed reduction device 12 includes an eccentric oscillating gear mechanism EMo as the speed reduction mechanism. The eccentric oscillating gear mechanism EMo includes an input gear 16 that receives power from the motor pinion 14, a drive eccentric body shaft 18 that rotates integrally with the input gear 16, and the drive eccentric body shaft 18 (via the eccentric body 20). A) an oscillating body (external gear) 22 that is eccentrically oscillated, and carriers 26 and 28 that are synchronized with the rotation components of the oscillating body 22. “The carriers 26, 28 are synchronized with the rotation component of the rocking body 22” means that when the carriers 26, 28 are assembled in a rotatable state, the carriers 26, 28 accompany the rotation of the rocking body 22. Rotates at the same speed as the rotation of the oscillating body 22 (via the carrier pin 30), while when the carriers 26, 28 are fixedly assembled, This means that the rotation of the oscillator 22 is constrained (via 30). In this example, the carriers 26 and 28 are fixed to the external member 39. Therefore, the rocking body 22 is maintained in a state where its rotation is restrained by the carriers 26 and 28.

  As shown in FIG. 9, the oscillating body 22 has an oscillating body through-hole 33 in the axial direction having an inner diameter D1 at its radial center O1. Trochoidal external teeth 32 are formed on the outer periphery of the rocking body 22 and are in mesh with the internal teeth (pins) 36 of the internal gear 34. The internal gear 34 is integrated with the casing 38. The carriers 26 and 28 also have axial carrier through holes 40 and 42 having an inner diameter D2 (see FIGS. 7 and 8) at the center O2 in the radial direction of the carriers 26 and 28, respectively. The oscillating body through-hole 33 and the carrier through-holes 40 and 42 are formed as large as possible within a range not interfering with the drive eccentric body shaft hole 70, the input gear 16, and the like, and the speed reducer 12 is, for example, a joint of an industrial robot (not shown). When used for driving purposes, it is used to pass the control wire harness and the like.

  8 and 9 is a driven eccentric body shaft for stably supporting the eccentric rocking of the rocking body 22 in synchronization with the drive eccentric body shaft 18.

  When the input gear 16 is rotated by the rotation of the motor pinion 14, the drive eccentric body shaft 18 is rotated through the input gear 16, and by this rotation, the oscillator is moved through the eccentric body 20 formed on the drive eccentric body shaft 18. 22 swings. The rotation of the oscillating body 22 is restricted via the carrier pin 30 and the carriers 26 and 28, and the external teeth 32 formed on the oscillating body 22 mesh with the internal teeth 36 of the internal gear 34. . Therefore, eventually, the internal gear 34 (and the casing 38 integrated therewith) is obtained by one rotation of the drive eccentric body shaft 18 (one eccentric motion of the eccentric body 20 around the drive eccentric body shaft 18). However, the wheel rotates by an amount corresponding to the “difference” between the number of teeth of the internal teeth 36 of the internal gear 34 and the number of teeth of the external teeth 32 of the oscillator 22 (so-called frame rotation reduction action).

JP 2001-323972 A

  There is a strong demand for the rocking body through hole and the carrier through hole in this type of speed reducer to have as large an inner diameter as possible.

  However, in this type of speed reducer, because of its configuration, an input gear is provided or a large number of shafts or pins pass through the rocking body or carrier, so that the rocking body through hole or carrier through hole that can be formed can be formed. There is a problem that it is difficult to ensure a large inner diameter of the.

  The present invention has been made to solve such a conventional problem, and it is possible to form a through-hole having as large an area as possible in the center of the apparatus while maintaining the strength of the rocking body and the carrier high. An object of the present invention is to provide an eccentric oscillating gear mechanism.

  The present invention includes an input gear, a drive eccentric body shaft provided with the input gear and rotating integrally with the input gear, an eccentric rocker by the drive eccentric body shaft, and an axial rocking body at the center in the radial direction of the input gear. An eccentric oscillating gear mechanism comprising: an oscillating body having a through hole; and a carrier that is synchronized with a rotation component of the oscillating body and has an axial carrier through hole in a central portion in the radial direction of the oscillating body. A first configuration in which the hole has a circular section perpendicular to the axis and a center thereof deviates from a radial center of the oscillator, and the carrier through-hole has a circular section perpendicular to the axis; In addition, at least one of the second configurations in which the center is shifted from the radial center of the carrier is established, thereby solving the above-described problem.

  Conventionally, a rocking body through-hole or carrier through-hole (hereinafter collectively referred to simply as a central through-hole) in the center of the reduction gear is formed so that the center thereof coincides with the center of the rocking body or the carrier. It was.

  In contrast, in the present invention, when the cross section perpendicular to the axis of the central through hole is circular, the center of the central through hole is formed at a position shifted from the radial center of the oscillator or carrier. Yes. Alternatively, the cross section perpendicular to the axis of the central through hole itself is formed in a non-circular shape. As a result, a through hole can be rationally formed in the central portion of a large number of shafts, pins, or input gears penetrating the oscillating body and the carrier, and the interval between the holes is secured. It becomes easy.

  According to the present invention, the central through-hole of the eccentric oscillating gear mechanism can be secured and formed as large as possible while maintaining the strength of the oscillating body and the carrier. A central through hole having a maximum area can be formed at the center in the radial direction of the mounted reduction gear.

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

  1 to 3 correspond to FIGS. 7 to 9 of the conventional example.

  The reduction gear 112 is provided with an input gear 116, a drive eccentric body shaft 118 provided with the input gear 116, and eccentrically oscillated by the drive eccentric body shaft 118, and at the center in the radial direction thereof. A oscillating body (external gear) 122 having an oscillating body through-hole 133 in the axial direction, and a carrier that synchronizes with the rotation component of the oscillating body 122 and has axial carrier through-holes 140 and 142 at the center in the radial direction of the oscillating body 122. , And an eccentric oscillating gear mechanism EM1 provided with 126 and 128.

  “The carriers 126 and 128 are synchronized with the rotation component of the oscillating body 122” means that when the carriers 126 and 128 are assembled in a rotatable state, the carriers 126 and 128 are rotated along with the rotation of the oscillating body 122. Rotates at the same speed as the rotation of the rocker 122 (via the carrier pin 130), while the carriers 126, 128 are fixedly assembled (by the carrier pins 128). This means that the rotation of the oscillator 122 is constrained (via 130). In this embodiment, the carriers 126 and 128 are fixed to the external member 139. Therefore, the rocking body 122 is maintained in a state where its rotation is restrained by the carriers 126 and 128.

  Explaining from the input stage side of the eccentric oscillating gear mechanism EM1, a pinion 114 is formed on the motor shaft 110 of a motor (not shown). The pinion 114 is meshed with the input gear 116. The input gear 116 is provided on the drive eccentric body shaft 118, and the drive eccentric body shaft 118 can rotate integrally with the input gear 116. An eccentric body 120 having an eccentric amount ΔE is formed on the drive eccentric body shaft 118, and an oscillating body 122 is incorporated on the outer periphery of the eccentric body 120 via a bearing 121. Trochoidal external teeth 132 are formed on the outer periphery of the oscillator 122. The external teeth 132 are in mesh with the internal teeth (roller-shaped pins) 134 of the internal gear 134. The internal gear 134 is integrated with the casing 138 and is rotatably supported by the carriers 126 and 128 via the bearings 161 and 163.

  In addition to the drive eccentric body shaft 118, two follower eccentric body shafts 144 and six carrier pins 130 pass through the rocking body 122. The oscillating body 122 is incorporated into an eccentric body shaft hole 171 formed therein via a cylindrical roller bearing 121. The drive eccentric body shaft 118 receives the rotation of the input gear 116, rotates integrally with the input gear 116, and swings the swing body 122 via the roller bearing 121 incorporated on the eccentric body 120. To work.

  The drive eccentric body shaft 118 is supported by shaft holes 170 of carriers 126 and 128 disposed on both sides in the axial direction of the rocking body 122 via a tapered roller bearing 172. In this embodiment, the carriers 126 and 128 are fixed to the external member 139 via bolts (only bolt holes are shown) 137.

  The two driven eccentric body shafts 144 have the same amount of eccentricity ΔE as the eccentric body 120 of the drive eccentric body shaft 118 at the same axial position as the axial position where the eccentric body 120 of the drive eccentric body shaft 118 is formed. The eccentric body 152 (only the cross section is shown in FIG. 3) 152 is formed, and the eccentric body 152 is incorporated into the driven eccentric body shaft hole 146 of the swinging body 122 via the roller bearing 154 at the portion where the eccentric body 152 is formed. . 2 indicates a driven eccentric body shaft hole formed in the carrier 126, and reference numeral 149 is disposed between the driven eccentric body shaft hole 147 and the driven eccentric body shaft 144 in the carrier 126. The shown bearing is shown.

  The carrier pin 130 connects the carriers 126 and 128 via bolts 162. The carrier pin 130 is loosely fitted in the carrier pin hole 164 of the rocking body 122.

  Here, an oscillating body through-hole 133 is formed at the center of the oscillating body 122 in the radial direction. In addition, carrier through holes 140 and 142 are formed in the carriers 126 and 128. 2 and 3, the two-dot chain lines correspond to the oscillator through hole 33 and the carrier through hole 40 (42) in the above-described conventional example (in FIGS. 7 to 9), respectively. .

  As apparent from FIG. 3, the rocking body through hole 133 in this embodiment has an inner diameter D3 larger than the inner diameter D1 of the rocking body through hole 33 in the conventional example, and its center O3 is the center of the rocking body 122. (= Center of the conventional rocking body through-hole 33) The drive eccentric body shaft 118 is shifted to the opposite side in the radial direction (upper side in the figure) by a shift amount δ1 with respect to O1. From a different viewpoint, it can be understood that the center O3 of the oscillating body through-hole 133 is shifted from the center O1 of the oscillating body 122 toward the driven eccentric body shaft 144 by the shift amount δ1.

  As apparent from FIG. 2, the carrier through hole 140 (142) has an inner diameter D4 larger than the inner diameter D2 of the carrier through hole 40 (42) in the conventional example, and its axis O4 has carriers 126, 128. (= Center of the conventional carrier through hole 40 (42)) O2 is shifted to the drive eccentric body shaft 118 in the radial direction opposite side (upper side in the drawing) by the shift amount δ2. From a different viewpoint, it is assumed that the center O4 of the carrier through hole 140 (142) is shifted from the center O3 of the carrier 126 (128) by the shift amount δ2 toward the driven eccentric body shaft 144. You can also. In FIG. 1, the center O1 and the center O2, the center O3 and the center O4, and the shift amount δ1 and the shift amount δ2 appear to overlap, but this does not necessarily mean the same (see FIGS. 2 and 3). ).

  Next, the operation of the reduction gear 112 will be described.

  When the input gear 116 is rotated by the rotation of the motor pinion 114, the drive eccentric body shaft 118 is rotated through the input gear 116, and by this rotation, the oscillator is moved through the eccentric body 120 formed on the drive eccentric body shaft 118. 122 swings. The rotation of the rocking body 122 is restricted through the carrier pin 130 and the carriers 126 and 128. Further, the external teeth 132 formed on the rocking body 122 mesh with the internal teeth 136 of the internal gear 134. Therefore, eventually, the internal gear 134 (and the casing 138 integrated therewith) is obtained by one rotation of the drive eccentric body shaft 118 (one eccentric motion of the eccentric body 120 around the drive eccentric body shaft 118). Is rotated relative to the rocking body 122 whose rotation is restricted by an amount corresponding to the “difference” between the number of teeth of the internal teeth 136 of the internal gear 134 and the number of teeth of the external teeth 132 of the rocking body 122. (So-called frame rotation deceleration action).

  Here, the inner diameter D3 of the oscillating body through hole 133 is ensured to be larger than the inner diameter D1 of the conventional oscillating body through hole 33 by approximately twice the shift amount δ1. In spite of this, the same dimension L1 as that in the conventional case is secured between the rocking body through hole 133 and the large-diameter drive eccentric body shaft hole 170, and high strength is maintained. Further, the oscillating body through-hole 133 itself has a shift amount δ1 relative to the center of the oscillating body 122 (= the center of the conventional oscillating body through-hole 33) O1 in the radial direction opposite to the drive eccentric body shaft 118 (driven eccentric body shaft 144). Although only a small-diameter driven eccentric body shaft hole 146 and a carrier pin hole 164 are formed on the shifted side, these holes 146 and 164 are shifted to the upper side in the figure. Also, sufficient dimensions L2 and L3 are secured between the oscillating body through-hole 133 and each other. For this reason, sufficient strength is maintained even in this portion.

  Similarly, the inner diameter D4 of the carrier through hole 140 (142) of the carrier 126 (128) is larger than that of the conventional inner diameter D2 and is sized with respect to the drive eccentric body shaft hole 170 and the driven eccentric body shaft hole 146, respectively. L4 and L5 are secured and excellent strength characteristics are obtained.

  The configuration according to this embodiment has an advantage that the through hole itself has a circular shape while ensuring large inner diameters D3 and D4 of the rocking body through hole 133 and the carrier through hole 140 (142), so that processing is easy. .

  Next, an example of another embodiment of the present invention will be described with reference to FIGS. The speed reduction device 212 in this embodiment is characterized in that the rocking body 222 is driven by one drive eccentric body shaft 218 and eight inner pins 280 (with an inner roller 280A). The inner pin 280 itself does not have an eccentric portion, but the gap between the inner pin 280 and the inner pin hole 282 exactly matches the amount of eccentricity of the eccentric body 220 of the drive eccentric body shaft 218. Therefore, the inner pin 280 can also serve as the function of the driven eccentric body shaft 144 and the carrier pin 130 of the previous embodiment (the connection of the carriers 226 and 228 and the support of the eccentric rocking of the rocking body 222).

  In the speed reduction device 212 according to this configuration, only the drive eccentric body shaft hole 270 has a large diameter, the inner pin hole 282 has a small diameter, and the distance from the center O1 of each rocking body 222 is equal. As shown in FIG. 6, the oscillating body through-hole 233 has a non-circular shape (a circular shape having a recess) so as to avoid interference with the drive eccentric body shaft hole 270 and the input gear 216. As a result, the rocking body through-hole 233 is mostly outside the circle 251, that is, radially outside the circle concentric with the center of the rocking body 222 and in contact with the innermost radial side of the tip circle of the input gear 216. And a very large opening area is secured.

  Similarly, most of the carrier through hole 240 is concentric with the center O2 of the carrier 226 (228) and is closer to the innermost radial side of the tip circle of the input gear 216 than the circle 253 which is in contact with the carrier 226 (228). ) In the radial direction, and a very large opening area substantially the same shape as the oscillating body through hole 233 is secured.

  Other configurations and operations are substantially the same as those of the previous embodiment, and therefore, the same or similar parts in the figure are denoted by the same reference numerals with the last two digits, and redundant description is omitted.

  4 to 6, only the drive eccentric body shaft hole 270 is larger than the inner pin hole 282 and the dimension of the input gear 216 is substantially the same as the drive eccentric body shaft hole 270. The moving body through-hole 233 and the carrier through-hole 240 have a “non-circular shape” having recesses 135 and 145 at “one place” so as not to interfere with the drive eccentric body shaft hole 270 or the input gear 216, respectively. However, the specific shapes of the rocking body through hole 233 and the carrier through hole 240 in the present invention are not limited to this. In short, interference with holes or members that may cause interference when forming the central through hole (ie, through holes, inner pins, eccentric shafts, input gears, etc. formed in the rocking body or carrier) In order to avoid this, it is only necessary to have a non-circular shape that can ensure a predetermined distance from these holes and members when viewed from the axial direction. For example, a non-circular portion having a size formed along a circumference that overlaps with these holes and members when viewed from the axial direction, and a concave portion that avoids these holes and members. What is necessary is just to be made into circular shape. Although not shown, when there are a plurality of drive eccentric body shafts (when there are two or more large-diameter holes), two or more recesses are provided to avoid each drive eccentric body shaft. You may make it form the center part through-hole designed in various shapes. Of course, it is good also as a center part through-hole which has many recessed parts so that interference with each axis | shaft may be avoided.

 The speed reducer according to the present invention is particularly useful for applications that require a thick wire harness or the like to pass through the speed reducer, such as a joint drive device for an industrial robot.

The longitudinal cross-sectional view which shows an example of the speed reducer which concerns on embodiment of this invention Sectional view along the line II-II in FIG. Sectional view along the arrow III-III line of FIG. The longitudinal cross-sectional view which shows an example of the speed reducer which concerns on the other Example of this invention. Sectional drawing which follows the arrow VV line of FIG. Sectional view along line VI-VI in FIG. A longitudinal sectional view showing an example of a conventional speed reducer Sectional drawing which follows the arrow VIII-VIII line of FIG. Sectional drawing which follows the arrow IX-IX line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 114 ... Motor pinion 116 ... Input gear 118 ... Drive eccentric body axis | shaft 120 ... Eccentric body 122 ... Oscillator 126, 128 ... Carrier 130 ... Carrier pin 134 ... Internal gear 138 ... Casing 133 ... Oscillator through-hole 140, 142 ... Carrier Through hole 144... Driven eccentric body shaft 146... Driven eccentric body shaft hole 164... Carrier pin hole 170.

Claims (12)

An input gear, a drive eccentric shaft provided with the input gear and rotating integrally with the input gear, an eccentric swing by the drive eccentric shaft, and an axial swing body through-hole in the center in the radial direction of the input gear In an eccentric oscillating gear mechanism comprising: an oscillating body; and a carrier that is synchronized with a rotation component of the oscillating body and has a carrier through hole in an axial direction at the center in the radial direction thereof.
The rocking body through-hole has a first configuration in which a cross section perpendicular to the axis is circular, and a center thereof is deviated from a radial center of the rocking body;
In the second configuration, the carrier through-hole has a circular cross section perpendicular to the axis, and the center thereof is deviated from the radial center of the carrier.
An eccentric oscillating gear mechanism characterized in that at least one of the configurations is established. In claim 1,
An eccentric oscillating gear mechanism characterized in that the center of the oscillating body through hole is shifted in the radial direction opposite to the drive eccentric body axis with respect to the center of the oscillating body. In claim 1 or 2,
An eccentric oscillating gear mechanism characterized in that the center of the carrier through hole is shifted radially opposite to the drive eccentric body axis with respect to the center of the carrier. In any one of Claims 1-3, Furthermore,
A driven eccentric body shaft that supports the eccentric rocking of the rocking body in synchronization with the drive eccentric body shaft;
An eccentric oscillating gear mechanism characterized in that the center of the oscillating body through hole is shifted in the radial direction opposite to the drive eccentric body axis with respect to the center of the oscillating body. In any one of Claims 1-4, Furthermore,
A plurality of inner pins integrated with the carrier and synchronized with the rotation component of the rocking body;
An eccentric oscillating gear mechanism characterized in that the center of the oscillating body through hole is shifted in the radial direction opposite to the drive eccentric body axis with respect to the center of the oscillating body. An input gear, a drive eccentric shaft provided with the input gear and rotating integrally with the input gear, an eccentric swing by the drive eccentric shaft, and an axial swing body through-hole in the center in the radial direction of the input gear In an eccentric oscillating gear mechanism comprising: an oscillating body; and a carrier that is synchronized with a rotation component of the oscillating body and has a carrier through hole in an axial direction at the center in the radial direction thereof.
A first configuration in which the oscillator through hole has a non-circular shape in a cross section perpendicular to the axis;
Of the second configuration, in which the carrier through hole has a non-circular shape in a cross section perpendicular to the axis,
An eccentric oscillating gear mechanism characterized in that at least one of the configurations is established. In claim 6,
A part of the oscillating body through hole is concentric with the center of the oscillating body and is present on the radially outer side of the oscillating body with respect to a circle in contact with the radially innermost side of the tooth tip circle of the input gear. An eccentric oscillating gear mechanism. In claim 7,
A circular portion formed along a circumference of a size that overlaps at least one of the drive eccentric body shaft and the input gear when the oscillating body through-hole is viewed from the axial direction, the drive eccentric body shaft, An eccentric oscillating gear mechanism having a non-circular shape having a recess that avoids interference with the input gear. In any one of Claims 6-8,
A part of the carrier through-hole exists concentrically with the center of the carrier and is present on the radially outer side of the carrier with respect to a circle in contact with the radially innermost side of the tip circle of the input gear. Eccentric rocking gear mechanism. In claim 9,
The carrier through-hole, when viewed from the axial direction, has a circular portion formed along a circumference that overlaps at least one of the drive eccentric shaft and the input gear, and the drive eccentric shaft and the input. An eccentric oscillating gear mechanism having a non-circular shape having a recess that avoids interference with a gear. In any one of Claims 6-10, Furthermore,
An inner pin for extracting the rotation component of the rocking body and transmitting it to the carrier;
An eccentric oscillating gear mechanism characterized in that a part of the oscillating body through hole is concentric with the center of the oscillating body and is radially outward from the innermost circumferential circle in contact with the inner pin. In claim 11,
The rocking body through-hole has a non-circular shape having a circular portion formed along a circumference that overlaps the inner pin when viewed from the axial direction, and a concave portion that avoids interference with the inner pin. An eccentric oscillating gear mechanism characterized by that.

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