WO2019212001A1

WO2019212001A1 - Reducer

Info

Publication number: WO2019212001A1
Application number: PCT/JP2019/017112
Authority: WO
Inventors: 靖梶原
Original assignee: 株式会社エンプラス
Priority date: 2018-05-02
Filing date: 2019-04-23
Publication date: 2019-11-07
Also published as: JP2019194486A

Abstract

[Problem] To provide a reducer which is capable of exerting the same function as that of a ball reducer, and has a simple structure, and in which the number of components is small and the number of assembly steps can be reduced. [Solution] A reducer 1 is provided with: an eccentric cam 3 that rotates integratedly with a drive shaft 2; oscillating bodies 4 that are oscillated by the eccentric cam 3; a fixation member 5 which is disposed so as to face one lateral surface side of each of the oscillating bodies 4; and an output-side rotating body 6 which is disposed so as to face the other lateral surface side of each of the oscillating bodies 4 and which rotates relatively with respect to the fixation member 5. In the oscillating bodies 4, oscillating parts 17 are formed integrally with leading ends of arm parts 16 which are elastically deformable. A first truncated cone-shaped portion 17a of each of the oscillating parts 17 is radially guided through a radial groove 20 in the output-side rotating body 6, and a second truncated cone-shaped portion 17b of each of the oscillating parts 17 is guided, in a wave shape along the circumferential direction, through an annular wave-shaped groove 21 in the fixation member 5. Each of the oscillating bodies 4 and the output-side rotating body 6 are coupled by means of a rotary coupling means K so as to rotate together.

Description

Decelerator

This invention relates to a speed reducer used to decelerate and transmit rotation.

Conventionally used gear reducers are configured by combining a plurality of gears, so it is difficult to eliminate backlash, and it is also difficult to obtain a small reduction ratio and a large reduction ratio. . Therefore, a ball reducer has been developed to eliminate the drawbacks of the gear reducer.

FIG. 12 is a view showing such a conventional ball speed reducer 100. 12A is a longitudinal sectional view of a conventional ball speed reducer 100, and FIG. 12B is a view showing the ball speed reducer 100 cut along line A9-A9 in FIG. 12A. FIG.

As shown in FIG. 12, in the ball reducer 100, an eccentric rotating plate 104 is attached to the outer peripheral side of the eccentric cam 102 formed on the input shaft 101 via a bearing 103, and the eccentric rotating plate 104 is the eccentric cam 102. Is driven eccentrically. Further, in this ball speed reducer 100, output side rotating bodies 105 connected to an output shaft (not shown) are arranged on both sides on the radially inner side of the eccentric rotating plate 104, and the input shaft 101 is an output side rotating body. It is supported on the inner peripheral side of 105 through a bearing 106 so as to be relatively rotatable. Further, in this ball speed reducer 100, fixing members 107 fixed to a part of an industrial robot or the like are arranged on both sides on the radially outer side of the eccentric rotating plate 104 via balls 108, respectively. A rotating body 105 is rotatably supported on the inner peripheral side of the fixed member 107 via a bearing 110. The ball 108 sandwiched between the eccentric rotating plate 104 and the fixing member 107 is formed by a first corrugated groove (first cycloid groove formed by an outer cycloid curve) 111 formed on the side surface of the eccentric rotating plate 104 and the fixing member 107. The eccentric rotating plate 104 is engaged with a second corrugated groove (second cycloid groove formed by an inner cycloid curve) 112 formed on the inner side surface (side surface facing the eccentric rotating plate 104) so as to roll. And the fixing member 107 are connected. The wave number of the second corrugated groove 112 is formed so as to be two more than the wave number of the first corrugated groove 111.

Further, the output-side rotator 105 is connected to the eccentric rotating plate 104 via the eccentric absorbing mechanism 113. The eccentric absorbing mechanism 113 allows the eccentric rotating plate 104 to move eccentrically with respect to the output side rotating body 105 (absorbs the eccentricity of the eccentric rotating plate 104). The rotation is transmitted to the output side rotating body 105. The eccentric absorbing mechanism 113 includes a plurality of balls 114 interposed between the eccentric rotating plate 104 and the output-side rotating body 105, and a driving annular groove 115 of the eccentric rotating plate 104 that accommodates the balls 114 in a rollable manner. And a driven annular groove 116 of the output side rotator 105. The shape and size of the driving annular groove 115 and the driven annular groove 116 are determined in consideration of the amount of eccentricity of the eccentric cam 102, and the ball 114 when the eccentric rotating plate 104 rotates eccentrically with respect to the rotation center of the input shaft 101. The output-side rotator 105 can rotate integrally with the eccentric rotating plate 104 via a ball 114 (see Patent Document 1).

In such a conventional ball speed reducer 100, for example, when the wave number of the first wave groove 111 of the eccentric rotating plate 104 is N-2 and the wave number of the second wave groove 112 of the fixed member 107 is N, the input shaft When 101 is rotationally driven by an electric motor (not shown) or the like, the eccentric rotating plate 104 is eccentrically driven by the eccentric cam 102 of the input shaft 101, and the output side rotating body 105 is integrated with the eccentric rotating plate 104 via the eccentric absorbing mechanism 113. The output-side rotator 105 rotates -2 / (N-2) with respect to one rotation of the input shaft 101 (2 / (N- in the direction opposite to the rotation direction of the input shaft 101). 2) Rotate). That is, in the conventional ball speed reducer 100, when the wave number of the first corrugated groove 111 of the eccentric rotating plate 104 is N-2 and the wave number of the second corrugated groove 112 of the fixed member 107 is N, the reduction ratio is 2 / (N-2).

JP-A-5-10400

However, since the conventional ball speed reducer 100 shown in FIG. 12 rotates the eccentric rotating plate 104 and the output side rotating body 105 integrally, the output side rotating body 105 is eccentrically rotated via the eccentric absorbing mechanism 113. The structure is complicated, the number of parts is large, and the number of assembly steps is increased.

Therefore, an object of the present invention is to provide a speed reducer that can exhibit the same function as a ball speed reducer, has a simple structure, has a small number of parts, and can reduce the number of assembly steps.

The present invention relates to the speed reducer 1 that decelerates and transmits the rotation of the input side rotating body 2 to the output side rotating body 6. The speed reducer 1 according to the present invention is fitted to an

eccentric cam

3, 43 that rotates together with the input side rotator 2, and is fitted to the

eccentric cam

3, 43 so as to be relatively rotatable, and swings by the

eccentric cam

3, 43. The oscillating body 4 to be moved, the oscillating body 4 is disposed so as to face one side surface side of the oscillating body 4, and is fixed to the fixed member 5, and the other oscillating body 4 is opposed to the other side surface side. An output-side rotating body 6 that is disposed and rotates relative to the fixing member 5. The oscillating body 4 includes a plurality of

cam engaging portions

15 and 50 which are fitted to the

eccentric cams

3 and 43 so as to be relatively rotatable, and a plurality of radially extending parts around the rotation axis 11 of the input side rotating body 2. The arm portion 16 and the sliding portion 17 integrally formed at the tip of the arm portion 16 are integrally provided. Further, at least a part of the arm portion 16 can be elastically deformed. The sliding portion 17 protrudes from the arm portion 16 toward the output-side rotator 6 side, and protrudes from the arm portion 16 toward the fixing member 5 side. A second frustoconical portion 17b. Then, in a virtual plane orthogonal to the rotation axis 11 of the input side rotating body 2, a direction extending radially from the rotation axis 11 is a radial direction, along a virtual circle centered on the rotation axis 11. When the direction is the circumferential direction, a radial groove 20 for guiding the first truncated cone portion 17a of the rocking body 4 along the radial direction is formed on a side surface of the output side rotating body 6 facing the rocking body 4. At least as many as the arm portions 16 are formed, and on the side surface of the fixing member 5 facing the rocking body 4, the second truncated cone-shaped portion 17 b of the rocking body 4 is guided in a wave shape along the circumferential direction. The corrugated groove 21 is formed. The output-side rotator 6 is connected to the oscillating body 4 by means of a rotation linking means K, and the second truncated cone portion 17b is guided and moved by the corrugated groove 21 to move the oscillating body. When the moving body 4 rotates, it is rotated together with the rocking body 4.

The speed reducer according to the present invention is composed of few components such as an eccentric cam, a pair of oscillating bodies, a fixed member, and a pair of output side rotating bodies as well as being able to exhibit the same function as a conventional ball speed reducer. Since the structure is simpler than the conventional ball reducer, the number of assembly steps can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the reduction gear concerning 1st Embodiment of this invention, FIG.1 (a) is a front view of a reduction gear, FIG.1 (b) is a side view of a reduction gear, FIG.1 (c) is a reduction gear. It is a rear view. FIG. 2 is a cross-sectional view of the speed reducer according to the first embodiment of the present invention, and is a cross-sectional view of the speed reducer cut along the line A1-A1 of FIG. 3A and 3B are views showing an eccentric cam of the speed reducer according to the first embodiment of the present invention, in which FIG. 3A is a front view of the eccentric cam, and FIG. 3B is along the line A2-A2 in FIG. FIG. 3C is a rear view of the eccentric cam. It is a figure which shows the rocking | swiveling body of the reduction gear which concerns on 1st Embodiment of this invention, Fig.4 (a) is a front view of a rocking body, FIG.4 (b) follows the A3-A3 line | wire of FIG.4 (c). FIG. 4C is a rear view of the oscillating body. It is a figure which shows the fixing member of the reduction gear which concerns on 1st Embodiment of this invention, Fig.5 (a) is a front view of a fixing member, FIG.5 (b) is a side view of a fixing member, FIG.5 (c) is FIG. FIG. 5D is a sectional view of the fixing member cut along the line A4-A4 of FIG. 5A. It is a figure which shows the output side rotary body of the reduction gear which concerns on 1st Embodiment of this invention, FIG.6 (a) is a front view of an output side rotary body, FIG.6 (b) is a side view of an output side rotary body, 6C is a cross-sectional view of the output side rotating body cut along the line A5-A5 in FIG. 6A, and FIG. 6D is along the line A6-A6 in FIG. 6A. Sectional drawing of the output side rotary body cut | disconnected and shown in FIG.6 (e) are the rear views of an output side rotary body. FIG. 7A is a front view showing the reduction gear according to the first embodiment of the present invention with the second output-side rotating body, the second rocking body, and the fixing member removed, and FIG. FIG. 4 is a partial cross-sectional view of the speed reducer shown cut along line A7-A7 in FIG. FIG. 8A is a partial cross-sectional view of the speed reducer cut along line A8-A8 in FIG. 8B, and FIG. 8B is a speed reducer according to the first embodiment of the present invention. It is a rear view which removes and shows the 1st output side rotary body, the 2nd rocking body, and the 2nd output side rotary body. It is a longitudinal cross-sectional view of the reduction gear which concerns on 2nd Embodiment of this invention. It is a figure which shows the reduction gear which concerns on 3rd Embodiment of this invention. 11 (a-1) and 11 (a-2) are diagrams showing the relationship between the sliding portion and the radial groove and the sliding portion and the corrugated groove in the speed reducer according to the present invention. -1) and FIG. 11 (b-2) are views showing the relationship between the balls and radial grooves and the balls and corrugated grooves of a reduction gear according to a comparative example. FIG. 12A is a view showing a conventional ball reducer, FIG. 12A is a longitudinal sectional view of the ball reducer, and FIG. 12B is a sectional view taken along line A9-A9 in FIG. It is.

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

[First embodiment]
FIG.1 and FIG.2 is a figure which shows the reduction gear 1 which concerns on 1st Embodiment of this invention. FIG. 1A is a front view of the speed reducer 1. FIG. 1B is a side view of the speed reducer 1. FIG. 1C is a rear view of the speed reducer 1. 2 is a cross-sectional view of the speed reducer 1 cut along the line A1-A1 of FIG.

(Schematic configuration of reduction gear)
As shown in FIGS. 1 and 2, the speed reducer 1 according to this embodiment includes an eccentric cam 3 that rotates integrally with a drive shaft (input-side rotator) 2 and a pair that is swung by the eccentric cam 3. , The pair of

oscillating bodies

4, 4, the pair of

oscillating bodies

4, 4, and the pair of

oscillating bodies

4, 4. 6. In this reduction gear 1, an eccentric cam 3, a pair of rocking

bodies

4, 4, a fixing member 5, and a pair of output

side rotating bodies

6, 6 are formed of a resin material (for example, polyacetal (POM) polyamide (PA)). The rotation of the drive shaft 2 is decelerated from the pair of output

side rotating bodies

6 and 6 and transmitted to a driven member (not shown).

(Eccentric cam)
As shown in FIGS. 1 to 3, the eccentric cam 3 includes a cylindrical drive shaft fitting portion 8 having a shaft hole 7 fitted to the drive shaft 2, and an outer peripheral side of the drive shaft fitting portion 8. And an eccentric cam portion 10 formed integrally. The shaft hole 7 of the drive shaft fitting portion 8 has a D-shaped cross-section perpendicular to the rotation axis 11 (center of the shaft hole 7), and a drive having a D-shaped cross-section orthogonal to the rotation axis 11. The shaft 2 is fitted in a state of being prevented from rotating, and rotates together with the drive shaft 2. The eccentric cam portion 10 has a first eccentric cam portion 10A and a second eccentric cam portion 10B. The first eccentric cam portion 10 </ b> A and the second eccentric cam portion 10 </ b> B have a cylindrical shape, and the center 12 is offset with respect to the rotation axis 11 so that the phase is shifted by 180 ° in a virtual plane orthogonal to the rotation axis 11. I have a heart. That is, the center 12 of the first eccentric cam portion 10A is located on a center line 13 that passes through the rotation axis 11 and is parallel to the Y axis in a virtual plane orthogonal to the rotation axis 11. The position is shifted by a predetermined dimension (eccentricity e) in the Y direction. Further, the center 12 of the second eccentric cam portion 10B is located on a center line 13 that passes through the rotation axis 11 and is parallel to the Y axis in a virtual plane orthogonal to the rotation axis 11, and + Y from the rotation axis 11 It is displaced in the direction by a predetermined dimension (eccentricity e). And the 1st rocking body 4 is fitted by the outer peripheral surface 14 of 10 A of 1st eccentric cam parts so that relative rotation is possible. Moreover, the 2nd rocking body 4 is fitted by the outer peripheral surface 14 of the 2nd eccentric cam part 10B so that relative rotation is possible.

(Oscillator)
As shown in FIGS. 2 and 4, one of the pair of

oscillating bodies

4, 4 is the first oscillating body 4 that is oscillated by the first eccentric cam portion 10 </ b> A. The other of the pair of

oscillating bodies

4, 4 is the second oscillating body 4 that is oscillated by the second eccentric cam portion 10B. The second oscillating body 4 is used in a state where the same shape as the first oscillating body 4 is reversed. Such an oscillating body 4 includes a cylindrical boss portion 15 (cam engaging portion) fitted to the eccentric cam portion 10 so as to be relatively rotatable, and radially outward from an outer peripheral surface 15a of the boss portion 15. A plurality of arm portions 16 extending in a radial direction (radially extending around the rotation axis 11) and a sliding portion 17 integrally formed at the tip of the arm portion 16 are integrally provided. The arm portion 16 has a narrower width dimension at the distal end side than the root side, and a base end portion 18 (connection portion to the boss portion 15) having a smaller wall thickness than the other portions. It is easy to elastically deform. As described above, since the base end portion 18 is easily elastically deformed, the arm portion 16 changes its posture according to the eccentric state of the eccentric cam 3 when the oscillating body 4 oscillates. Allows smooth rocking motion.

The sliding portion 17 includes a first frustoconical portion 17a projecting from the arm portion 16 toward the output-side rotator 6, and a second frustoconical portion 17b projecting from the arm portion 16 toward the fixing member 5. And have. The first frustoconical portion 17a is engaged so as to be slidable in a radial groove 20 of the output side rotating body 6 described later (see FIG. 7). Further, the second frustoconical portion 17b is engaged so as to be slidable in a wave groove 21 of the fixing member 5 described later (see FIG. 8). A plurality of anti-rotation protrusions 22 formed at equal intervals on the end face of the boss portion 15 are engaged with an anti-rotation hole 23 of the output-side rotator 6 to be described later, so that the oscillating body 4 is opposed to the output-side rotator 6. The oscillating body 4 and the output side rotator 6 are connected so that they can oscillate and the oscillating body 4 can rotate the output side rotator 6 (see FIGS. 2, 6, and 7). In addition, although the base end portion 18 is more easily elastically deformed than the other portions, the arm portion 16 may be formed with a portion that is easily elastically deformed at a position radially outward from the base end portion 18. .

2, 4, and 7, the oscillating body 4 includes three caulking fixing protrusions 24 extending from one of the pair of output-

side rotators

6 and 6, and the pair of output-side rotators. In order not to contact the three caulking fixing protrusions 24 extending from the other of 6 and 6, the arm portion 16 is not formed at a position corresponding to the caulking fixing protrusions 24. As a result, in the oscillating body 4, the number of the radial grooves 20 of the output-side rotator 6 is 30, whereas the number of installation portions of the arm portion 16 is 24.

(Fixing member)
As shown in FIGS. 1, 2, and 5, the fixing member 5 is disposed between a pair of oscillating bodies 4, 4 (first oscillating body 4 and second oscillating body 4). It is located so as to oppose the side surface side. The fixing member 5 is a plate-like body having a rectangular shape in plan view, and is fixed to a fixed member such as a frame by bolts inserted into bolt holes 25 at four corners. The fixing member 5 is formed such that a hole 26 that accommodates the drive shaft 2, the eccentric cam 3, and the like radially inward penetrates in the plate thickness direction. The hole 26 of the fixing member 5 is formed so that the center 27 is concentric with the rotational axis 11 of the drive shaft 2. Then, on one of both side surfaces of the fixing member 5, the second frustoconical portion 17 b of the first oscillator 4 is rotated in the circumferential direction (in a virtual plane orthogonal to the rotational axis 11 of the drive shaft 2). An annular first corrugated groove 21 that is guided in a wave shape along a virtual circle centered on the axis 11 is formed. The first corrugated groove 21 has a crest side (radially outward) side wall 28 a and a trough side (radially inward side) side wall 28 b in sliding contact with the second frustoconical portion 17 b of the oscillator 4. It has become. In addition, an annular second corrugated groove 21 is formed on the other of both side surfaces of the fixing member 5 to guide the second frustoconical portion 17b of the second oscillator 4 in a wave shape along the circumferential direction. Yes. The second corrugated groove 21 has a shape obtained by rotating the first corrugated groove 21 about the center 27 by 180 ° in a virtual plane orthogonal to the center 27 (rotation axis 11) (a shape whose phase is shifted by 180 °). It has become. As shown in FIG. 11 (a-1), the corrugated groove 21 has a trapezoidal cross-sectional shape at right angles to the groove. It is formed at the same angle as the taper angle, and both

side walls

28a, 28b are in sliding contact with the generatrix of the outer peripheral surface of the second truncated cone portion 17b. In the present embodiment, the corrugated groove 21 has a wave number of 29 compared to 30 in the radial groove 20 of the output side rotating body 6 described later, but it is easy to understand the contents of the invention. However, the present invention is not limited to such an example, and the optimum wave number is determined according to the size of the speed reducer 1 and the like.

(Output side rotating body)
As shown in FIGS. 1, 2, and 6, a pair of output side rotating bodies 6 are arranged so as to sandwich a fixing member 5 and a pair of

oscillating bodies

4, 4 arranged on both sides of the fixing member 5. The shaft hole 30 formed in the center portion is fitted to the outer peripheral surface of the drive shaft fitting portion 8 of the eccentric cam 3 so as to be relatively rotatable. One of the pair of output-

side rotators

6 and 6 is disposed to face the other side surface of the first oscillating body 4, and will be described separately from the other of the pair of output-

side rotators

6 and 6. When it is necessary, for convenience of explanation, the first output-side rotator 6 is referred to. Further, the other of the pair of

output side rotators

6 and 6 is disposed so as to face the other side surface of the second oscillating body 4, and is distinguished from one of the pair of

output side rotators

6 and 6. When it is necessary to do this, for convenience of explanation, it is referred to as a second output side rotating body 6. The second output-side rotator 6 rotates the first output-side rotator 6 by 180 ° around the rotation axis 31 concentric with the rotation axis 11 of the drive shaft 2 and faces the first output-side rotator 6. It is used in the state letting it. On the side surface (second side surface) of the output side rotator 6 that faces the oscillating body 4, the first frustoconical portion 17 a of the oscillating body 4 is arranged in a radial direction (in a virtual plane orthogonal to the rotational axis 11 of the drive shaft 2). , A plurality of radial grooves 20 that are guided along the direction extending radially from the rotation axis 11 of the drive shaft 2 are formed at equal intervals. As shown in FIG. 11 (a-1), the radial groove 20 has a trapezoidal cross-sectional shape perpendicular to the radial direction (groove perpendicular cross-sectional shape), and the side walls 32 and 32 (inclined surfaces) on both sides. The inclination angle is the same as the taper angle of the outer peripheral surface of the first frustoconical portion 17a, and is in sliding contact with the generatrix of the outer peripheral surface of the first frustoconical portion 17a.

Further, the output-side rotator 6 is formed with an oscillating body accommodation recess 33 that accommodates a part of the base side of the arm portion 16 of the oscillating body 4 on the radially inner side of the radial groove 20. The oscillating body accommodating recess 33 accommodates a portion of the oscillating body 4 on the base side of the arm portion 16 and protruding in the width direction from the distal end side of the arm portion 16. Further, in the oscillator housing recess 33, the caulking fixing protrusions 24 and the caulking holes 34 are alternately formed at equal intervals at three positions. The caulking fixing projection 24 is formed on the side surface (side surface on which the radial groove 20 is formed) facing the oscillating body 4, and has a large-diameter portion 24a on the root side and a small-diameter portion 24b on the tip side. ing. The caulking hole 34 includes a small-diameter hole portion 34 a that opens into the swinging-body receiving recess 33, and a large-diameter hole portion 34 b that has a larger diameter than the small-diameter hole portion 34 a and opens toward the outer surface of the output-side rotating body 6. ,have. The small diameter hole portion 34 a of the caulking hole 34 is formed to have a slightly larger diameter than the small diameter portion 24 b of the caulking fixing projection 24 and smaller diameter than the large diameter portion 24 a of the caulking fixing projection 24. The caulking fixing projection 24 of one of the pair of output-

side rotators

6 and 6 has a small-diameter portion 24b inserted into the other caulking hole 34 of the pair of output-

side rotators

6 and 6, and a pair of large-diameter portions 24a. The small diameter portion 24b that protrudes toward the large diameter hole portion 34b of the caulking hole 34 in a state of being abutted against the side surfaces of the output

side rotating bodies

6 and 6 is a head 35 having a larger diameter than the small diameter hole portion 34a by heat caulking. By being deformed, the one and the other of the pair of output

side rotating bodies

6 and 6 can be fixed. In FIG. 6, the caulking fixing protrusion 24 indicates the shape after heat caulking with a solid line, and the shape of the small diameter portion 24 b before heat caulking is indicated with a dotted line.

Further, the output-side rotating body 6 has a rotation-preventing hole 23 for accommodating the rotation-preventing protrusion 22 of the rocking body 4 in the rocking-body housing recess 33. The anti-rotation holes 23 are formed in the same number as the anti-rotation protrusions 22 of the oscillating body 4, and 2e (the eccentric amount e of the first eccentric cam portion 10A and the second eccentric cam portion 10B is between the anti-rotation protrusions 22). It is a round hole with a bottom having a diameter in which a gap of 2 times) is generated. When the rocking body 4 is swung by the eccentric cam 3, the rotation preventing hole 23 has such an inner peripheral surface that is in sliding contact with the rotation preventing projection 22 of the rocking body 4, and the sliding portion 17 of the rocking body 4 is in a wavy groove. When the oscillating body 4 is moved along the circumferential direction 21 and rotates, the output-side rotator 6 functions together with the oscillating body 4. As described above, the rotation-preventing hole 23 of the output-side rotator 6 and the rotation-preventing protrusion 22 of the oscillating body 4 constitute a rotation linking means K that rotates the output-side rotator 6 and the oscillating body 4 together. In the rotation connecting means K, the rotation preventing projection 22 may be formed on the output side rotating body 6 and the rotation preventing hole 23 may be formed on the rocking body 4.

(Decelerator operation)
In the speed reducer 1 according to the present embodiment, when the drive shaft 2 and the eccentric cam 3 rotate together, the first oscillator 4 and the eccentric cam 3 fitted to the first eccentric cam portion 10A of the eccentric cam 3 are connected. The second oscillating body 4 fitted to the second eccentric cam portion 10B is oscillated while causing a phase shift of 180 °. At this time, the sliding portion 17 of the first oscillating body 4 and the second oscillating body 4 slides in the radial groove 20 of the output-side rotator 6 and moves in the circumferential direction in the corrugated groove 21 of the fixing member 5. The slide is moved. As a result, the first rocking body 4 and the second rocking body 4 are rotated around the center 27 of the fixing member 5 (the rotation axis 11 of the drive shaft 2). Then, the first output-side rotator 6 and the second output-side rotator 6 are moved together by the rotation connecting means K (the anti-rotation hole 23 and the anti-rotation protrusion 22 engaged with the anti-rotation hole 23). It is rotated together with the moving body 4 and the second oscillating body 4. In the speed reducer 1 according to this embodiment, the number of grooves in the radial groove 20 of the output-side rotating body 6 is 30, whereas the number of waves in the corrugated groove 21 of the fixing member 5 is 29. When the shaft 2 and the eccentric cam 3 are rotated 30 times, the rocking body 4 and the output side rotating body 6 are rotated once. That is, the reduction gear 1 according to the present embodiment has a reduction ratio of 1/30.

(Effect of this embodiment)
The speed reducer 1 according to the present embodiment having the above-described structure has the same function as the conventional ball speed reducer 100 (compared to a gear speed reducer, can eliminate backlash, and can transmit rotation with a large reduction ratio. The conventional ball speed reducer 100 is composed of a small number of components such as the eccentric cam 3, the pair of swinging

bodies

4, 4, the fixing member 5, and the pair of output

side rotating bodies

6, 6. Since the structure is simpler than that, the number of assembly steps can be reduced.

In addition, the speed reducer 1 according to the present embodiment is entirely formed of a resin material (the eccentric cam 3, the pair of swinging

bodies

4, 4, the fixing member 5, and the pair of output side rotating bodies 6, 6). Compared to the conventional ball reducer 100, the number of parts is small and the structure is simple. Therefore, the size and weight can be reduced as compared with the conventional ball reducer 100.

Moreover, since the reduction gear 1 which concerns on this embodiment can form all the components by injection molding, it can reduce a process man-hour compared with the case where a component is formed by machining (cutting, polishing, etc.). Product cost can be reduced.

Further, in the speed reducer 1 according to the present embodiment, both side walls 32 and 32 (inclined surfaces) of the radial groove 20 of the output-side rotator 6 can be in line contact with the generatrix of the first truncated cone portion 17a of the oscillator 4. Since both

side walls

28a, 28b (inclined surfaces) of the corrugated groove 21 of the fixing member 5 can come into line contact with the generatrix of the second truncated cone portion 17b of the oscillator 4 (FIG. 11 (a-1)). Reference), even if the fixing member 5 and the output-side rotator 6 are displaced away from each other, the contact state between the

side walls

32, 32 of the radial groove 20 and the bus bar of the first truncated cone portion 17a and the corrugated groove 21 can be maintained without changing the contact state between the both

side walls

28a, 28b of 21 and the bus bar of the second frustoconical portion 17b (see FIG. 11 (a-2)), and ratcheting is unlikely to occur. As shown in FIG. 11 (b-1), the ball reducer in which the cross-sectional shape perpendicular to the radial grooves 37 and the corrugated grooves 38 that engage with the balls 36 is an arc is the fixed member 5 and the output side rotation. When the body 6 is displaced in the direction away from the body 6, the angle θ formed by the line segment 40 connecting the contact positions of the ball 36 and the radial groove 37 and the ball 36 and the corrugated groove 38 and the rotation direction of the output side rotating body 6 is changed. It greatly changes (see FIG. 11B-2), and ratcheting is more likely to occur than the speed reducer 1 according to the present embodiment.

Further, since the speed reducer 1 according to the present embodiment is swung in a state where the first rocking body 4 and the second rocking body 4 are 180 degrees out of phase, the rotation transmission torque is balanced in the circumferential direction. Rotation can be transmitted smoothly, and vibration and noise are not easily generated during rotation transmission.

[Second Embodiment]
FIG. 9 is a longitudinal sectional view showing the reduction gear 1 according to the second embodiment of the present invention, and is a view showing a first modification of the reduction gear 1 according to the first embodiment. In addition, description of the reduction gear 1 which concerns on this embodiment abbreviate | omits description of the part which is common in the reduction gear 1 which concerns on 1st Embodiment suitably.

The speed reducer 1 according to this embodiment shown in FIG. 9 omits the first rocking body 4 and the first output side rotating body 6 of the speed reducer 1 according to the first embodiment, and the speed reducer according to the first embodiment. The pressing plate 41 and the caulking hole 34 of the output-side rotating body 6 of the machine 1 are omitted, and the holding plate 41 is fixed to the radially outer end of the fixing member 5 so that the output-side rotating body 6 is separated from the fixing member 5. It has a structure to suppress by. In the speed reducer 1 according to the present embodiment, the same number of arm portions 16 of the oscillating body 4 as the radial grooves 20 may be formed.

The speed reducer 1 according to Modification 1 having such a configuration can be used when the rotation transmission torque is relatively small (in the case of a rotation transmission torque smaller than the rotation transmission torque of the reduction gear 1 according to the first embodiment). The same effect as that of the speed reducer 1 according to the first embodiment can be obtained, and the size and weight can be reduced as compared with the speed reducer 1 according to the first embodiment.

[Third Embodiment]
FIG. 10 is a diagram illustrating the speed reducer 1 according to the third embodiment of the present invention, and is a diagram illustrating a second modification of the speed reducer 1 according to the first embodiment. In addition, Fig.10 (a) is a longitudinal cross-sectional view of the reduction gear 1 which concerns on this embodiment. FIG. 10B is a diagram of the gear reduction mechanism 42 when the output-side rotator 6 of the speed reducer 1 is removed and the speed reducer 1 is viewed along the direction of the arrow B1 in FIG. . Moreover, description of the reduction gear 1 which concerns on this embodiment abbreviate | omits description of the part which is common in the reduction gear 1 which concerns on 1st Embodiment suitably.

As shown in FIG. 10, the speed reducer 1 according to the present embodiment is configured such that the rotation of the drive shaft 2 is transmitted to the eccentric cam 43 via the gear speed reduction mechanism 42. The gear reduction mechanism 42 includes a drive gear 44 (small gear with the number of teeth Z1) formed on the front end side of the drive shaft 2, and a driven gear 45 (large gear with the number of teeth Z2 (Z2>) rotated by the drive gear 44. Z1)), and the rotation of the drive shaft 2 is transmitted to the eccentric cam 43 at a reduction ratio of Z1 / Z2. Three driven gears 45 are arranged around the drive gear 44 at equal intervals. Therefore, the drive gear 44 and the three driven gears 45 constitute three sets of gear reduction mechanisms 42. The driven gear 45 has support shafts 46 projecting from both sides of the central portion, and the support shafts 46 are engaged with the bearing holes 47 of the output-side rotator 6 so as to be relatively rotatable. In addition, eccentric cams 43 are formed on both side surfaces of the driven gear 45 so as to be eccentric with respect to the center 48 (rotation center) of the support shaft 46. The first oscillating body 4 and the second oscillating body are formed with three cam engaging holes 50 (cam engaging portions) that are fitted to the three eccentric cams 43 so as to be relatively rotatable. The eccentric cam 43 engaged with the cam engagement hole 50 formed in the first rocking body 4 so as to be relatively rotatable is relatively rotatable with respect to the cam engagement hole 50 formed in the second rocking body 4. Is formed so as to cause a phase shift of 180 ° with respect to the eccentric cam 43 engaged with the cam. The speed reducer 1 according to the present embodiment omits the caulking fixing protrusions 24 and the caulking holes 34 according to the first embodiment, and includes holding

plates

51 and 51 that are fixed to the radially outer end side of the fixing member 5. The pair of output-

side rotators

6 and 6 are sandwiched from both sides to prevent the pair of output-

side rotators

6 and 6 from being separated from the fixing member 5. Further, in the speed reducer 1 according to the present embodiment, the eccentric cam 43 and the support shaft 46 integral with the driven gear 45 constitute the rotation linking means K, and the oscillating body 4 and the output side are constituted by the rotation linking means K. When the rotator 6 is connected and the pair of

oscillating bodies

4, 4 rotate around the rotation axis 11 of the drive shaft 2, the pair of output-

side rotators

6, 6 rotate together with the pair of

oscillating bodies

4, 4. To do.

In the speed reducer 1 according to the present embodiment having such a configuration, the rotation of the drive shaft 2 is transmitted to the eccentric cam 43 while being decelerated via the gear reduction mechanism 42, and the eccentric cam 43 swings the rocking body 4. Let Therefore, the speed reducer 1 according to the present embodiment can obtain the same effect as that of the speed reducer 1 according to the first embodiment, as well as the speed reduction ratio of the gear speed reduction mechanism 42 in the first embodiment. It becomes possible to obtain a reduction ratio larger than that of the speed reducer 1.

[Modifications of First, Second, and Third Embodiments]
The speed reducer 1 according to the first and second embodiments is not limited to the case of being entirely formed of a resin material, and the eccentric cam 3 is formed of metal, and the heat of the oscillator 4 is transferred via the metal eccentric cam 3. Then, it may be allowed to escape to the drive shaft 2 side.

Further, the speed reducer 1 according to the third embodiment is not limited to the case where the entirety is made of a resin material, and the driven gear 45 and the pair of

eccentric cams

43 and 43 are made of metal, and the heat of the oscillator 4 is made of metal. You may make it escape to the drive shaft 2 side via the eccentric cam 43 and the reduction gear mechanism 42 (the driven gear 45 and the drive gear 44).

DESCRIPTION OF SYMBOLS 1 ... Reducer, 2 ... Drive shaft (input side rotary body), 3, 43 ... Eccentric cam, 4 ... Oscillating body, 5 ... Fixed member, 6 ... Output side rotary body, 15 ... Boss Part (cam engaging part), 16 ... arm part, 17 ... sliding part, 17a ... first frustoconical part, 17b ... second frustoconical part, 20 ... radial groove, 21 ... ... Wave groove, 50 ... Cam engagement hole (cam engagement part), K ... Rotation linking means

Claims

In the reducer that decelerates and transmits the rotation of the input side rotator to the output side rotator,
An eccentric cam that rotates together with the input side rotating body;
An oscillating body fitted to the eccentric cam so as to be relatively rotatable, and oscillated by the eccentric cam;
A fixing member disposed to face one side surface of the rocking body and fixed to a fixed member;
An output-side rotating body that is disposed so as to face the other side surface of the rocking body and that rotates relative to the fixing member;
The oscillating body includes a cam engagement portion that is fitted to the eccentric cam so as to be relatively rotatable, a plurality of arm portions that extend radially around a rotation axis of the input-side rotator, and a tip of the arm portion And a sliding portion formed integrally with the
At least a part of the arm part can be elastically deformed,
The sliding portion includes a first truncated cone-shaped portion projecting from the arm portion toward the output-side rotating body side, and a second truncated cone-shaped portion projecting from the arm portion toward the fixing member side. Have
In a virtual plane orthogonal to the rotation axis of the input side rotating body, a direction extending radially from the rotation axis is a radial direction, and a direction along a virtual circle centered on the rotation axis is a circumferential direction. A radial groove for guiding the first frustoconical portion of the oscillating body along the radial direction is formed on the side surface of the output side rotator facing the oscillating body, at least as many as the arm portion, and the fixed An annular corrugated groove is formed on a side surface of the member facing the rocking body to guide the second frustoconical portion of the rocking body in a wave shape along the circumferential direction,
The output-side rotator is connected to the oscillating body by a rotating linking means, and when the oscillating body rotates by the second frustoconical portion being guided and moved by the wave groove, It can be rotated together with the rocking body,
A reduction gear characterized by that.
The fixing member is provided with the swinging body on both side surfaces,
A pair of the output side rotating bodies are arranged so as to sandwich the fixing member and the pair of swinging bodies,
The pair of output-side rotators are connected so as to rotate integrally.
The speed reducer according to claim 1.
When the rocking body located on one side of the both sides of the fixing member is a first rocking body and the rocking body located on the other side of the both sides of the fixing member is a second rocking body, The radial groove for guiding the first frustoconical portion of the first oscillator along the radial direction and the second frustoconical portion of the first oscillator in a wave shape along the circumferential direction. The annular corrugated groove is configured to guide the first frustoconical portion of the second oscillating body along the radial direction and the second frustoconical portion of the second oscillating body to the second frustoconical portion. With respect to the annular corrugated groove guided in a wave shape along the circumferential direction, the phase is formed so as to be shifted by 180 °,
The speed reducer according to claim 2.
In the eccentric cam, the rotation of the output-side rotator is reduced and transmitted through a reduction gear mechanism.
The speed reducer according to any one of claims 1 to 3, characterized in that: