JP2002266955A - Pivoting inscribing engagement planetary gear mechanism and angle transmission error reduction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce an angle transmission error at the time of power transmission without receiving a restriction such as a difference of the number of teeth, etc. SOLUTION: In the pivoting inscribing engagement planetary gear mechanism, external gear groups 105a, 105b are constituted by making a plurality of external gears A1, A2, A3 processed using the same processing machine eccentric to the same direction. The external gears A1, A2, A3 in the external gear groups 105a, 105b are incorporated to an internal gear 110 in the state that rotation direction phases are deviated to each other making the processing state as a reference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oscillating internal meshing planetary gear mechanism incorporating an external gear.
In particular, the present invention relates to a technique for reducing an angle transmission error (fluctuation in angular velocity) when transmitting rotational power.

[0002]

2. Description of the Related Art Conventionally, a first shaft, an external gear mounted eccentrically with respect to the first shaft through an eccentric body provided on the first shaft, and an external gear are provided. 2. Description of the Related Art A swinging internally meshing planetary gear mechanism including an internally geared internal gear and a second shaft connected to the external gear via means for transmitting only the rotation component of the external gear is widely known. Have been.

FIGS. 5 and 6 show a conventional example employing two external gears. In this conventional example, the first shaft 1 is an input shaft,
The above-described mechanism is applied to a “reduction gear” by fixing the internal gear 10 while using the second shaft 2 as an output shaft.

The input shaft 1 has a predetermined phase difference (18 in this example).
0 °), the eccentric bodies 3a, 3b are fitted. The eccentric bodies 3a and 3b are integrated. External gears 5a, 5b are attached to the respective eccentric bodies 3a, 3b via bearings 4a, 4b. These external gears 5a, 5
b, a plurality of inner roller holes 6a and 6b are provided, and an inner pin 7 and an inner roller 8 are fitted into the inner roller holes 6a and 6b.

[0005] On the outer periphery of the external gears 5a and 5b, external teeth 9 such as a trochoid tooth shape are provided. The external teeth 9 are internally meshed with an internal gear 10 fixed to a casing 12. More specifically, the internal gear of the internal gear 10 has a structure in which the external pin 11 is loosely fitted into the pin groove 13 and is easily rotated.

The inner pin 7 penetrating the external gears 5a, 5b is fixed or fitted to the output shaft 2.

When the input shaft 1 makes one rotation, the eccentric bodies 3a, 3b
Makes one revolution. By one rotation of the eccentric bodies 3a and 3b,
The external gears 5a and 5b also try to perform oscillating rotation around the input shaft 1. However, since the rotation of the external gears 5a and 5b is restricted by the internal gear 10, the external gears 5a and 5b Mostly only swinging while touching.

Now, for example, if the number of teeth of the external gears 5a and 5b is N and the number of teeth of the internal gear 10 is N + 1, the difference in the number of teeth is 1. Therefore, each time the input shaft 1 rotates, the external gears 5 a and 5 b are connected to the internal gear 1 fixed to the casing 12.
It is shifted (rotated) by one tooth with respect to 0.
This means that one rotation of the input shaft 1 has been reduced to -1 / N rotation of the external gear.

The rotation of the external gears 5a, 5b is absorbed by the gap between the inner roller holes 6a, 6b and the inner roller 8 so that the swinging component is absorbed.
To the output shaft 2.

Here, the inner roller holes 6a and 6b and the inner pin 7 (inner roller 8) form a "constant speed internal gear mechanism".

As a result, a speed reduction of -1 / N is achieved. In general, this reduction ratio is expressed as: reduction ratio I =-(number of internal teeth-number of external teeth) / (number of external teeth).

In this conventional example, the internal gear 10 of the swinging internally meshing planetary gear mechanism is fixed, the first shaft 1 is used as an input shaft,
Although the second shaft 2 is used as the output shaft, the speed reducer can also be configured by fixing the second shaft 2 and using the first shaft 1 as the input shaft and the internal gear 10 as the output shaft. Further, by inverting these inputs and outputs, it is also possible to configure a gearbox.

Incidentally, Japanese Patent Application Laid-Open No. 60-260737,
Alternatively, U.S. Pat. No. 3,129,611 or the like proposes an oscillating internally meshing planetary gear mechanism of the type in which the external gear is oscillated through a plurality of eccentric shafts after the first stage of deceleration is performed by a parallel shaft gear. However, except that the rotation of the input shaft is equally decelerated and distributed to the plurality of eccentric shafts, the structure is almost the same as that of the oscillating internally meshing planetary gear mechanism already described with reference to FIGS. Has become.

[0014]

Generally, in the involute tooth profile, even if there is an error in the center-to-center distance of the meshing gears (as long as the center-to-center distance is fixed), the input / output rotational speed ratio is set from the set value. Although there is no deviation, it is one of the major features of the trochoid tooth profile or cycloid tooth profile that the speed ratio periodically deviates from the set value if there is an error in the center-to-center distance (for example, daily publication). Kogyo Shimbun, Masanori Senba, "Gears", Vol. 1, p. 17).

In the oscillating internally meshing planetary gear mechanism, as described above, the external gears 5a and 5b are formed in a trochoid tooth shape. Therefore, if there is an error with respect to the design value in the distance between the centers of the pitch circles of the internal gear 10 and the external gears 5a and 5b, this error fluctuates for each rotation due to the operation, resulting in an angle transmission error (input rotation angle). And a deviation of the output rotation angle from the theoretical value) appears periodically, and this has a problem that this contributes to the excitation force in the rotation direction.

The above is what occurs when one external gear meshes with the internal gear. In particular, as in the conventional example, two gears are used under the condition of "difference in the number of teeth = 1". External gears 5a, 5
b, as shown in FIG. 7, the external gear 5a
And the angle transmission error B of the external gear 5b are superimposed and appear as a large angle transmission error C (= A + B).

Japanese Patent Application Laid-Open No.
There is a technique proposed in Japanese Patent No. 241283.
This reverses the conventional general idea that the difference in the number of teeth is “1” and sets “the difference in the number of teeth is an integral multiple of the number of external gears”. Since the present technology presupposes that there are a plurality of external gears, the difference in the number of teeth is always 2 or more in this proposal.

For example, as shown in FIG. 8, when two external gears 305a and 305b are considered, the internal gear 310
The difference between the number of teeth of the external gears 305a and 305b is set to an integral multiple of “2”, that is, an even number, and the number of teeth of the internal teeth 311 is even. The number is also set to an even number.

Under these conditions, the two external gears 305a, 305a
In a state where the outer gears 5b are superimposed, holes (for example, inner roller holes) penetrating the respective external teeth 309 and the respective external gears are machined, and the respective external gears 305a and 305b are set in the respective eccentric directions (180 ° opposite directions). Simply stagger it.

In this way, the two external gears 305
Since the meshing timing of the externally processed external teeth at a and 305b shifts by 180 degrees, the angular transmission errors of the external gears 305a and 305b act so as to cancel each other out, and as a whole, one rotation of the eccentric shaft One angle transmission error can be reduced.

However, Japanese Patent Application Laid-Open No. Hei 6-24128 discloses
As pointed out in Japanese Patent Publication No. 3, this technique was obtained as a result of reversing the conventional idea of "difference in the number of teeth = 1".

Therefore, since the reduction ratio I of the oscillating internal meshing planetary gear structure is I =-(difference in number of teeth) / (number of external teeth), the number of external teeth of the external gears 5a and 5b is reduced. When the number of teeth is considered to be constant, there is a problem in that when the number of teeth is set to “2”, the obtained reduction ratio is halved (as a numerical value is doubled) as compared with the case where the number of teeth is set to “1”.

Further, in response to the recent demand for higher precision of various types of mechanical equipment, further reduction of the angle transmission error has been demanded, and there are situations in which the above-mentioned solution cannot always cope sufficiently. There was a problem.

In these conventional examples, two or more external gears are prepared in order to secure a high transmission torque, and in order to maintain the overall dynamic balance, each external gear is placed in a different phase direction (here, 180). (A phase difference of degrees) and incorporated in the internal gear in a state of being eccentric. Therefore, when a high transmission torque is not required, one external gear may be sufficient.
In order to reduce the angle transmission error, it is necessary to adopt the above-mentioned oscillating internal meshing planetary gear structure in which two external gears and the difference in the number of teeth from the internal gear are two. , Leading to an increase in equipment costs.

The present invention has been made in view of the above problems, and achieves both a high acceleration / deceleration ratio and a reduction in angle transmission error, has excellent transmission characteristics, and can further reduce manufacturing costs. It is an object of the present invention to obtain a swinging internal meshing planetary gear mechanism.

[0026]

SUMMARY OF THE INVENTION The present invention provides a first shaft, an external gear that oscillates and rotates eccentrically with respect to the first shaft through an eccentric body, and an internal gear that meshes with the external gear. Oscillating internal meshing comprising: a tooth gear; and a second shaft having an inner pin loosely fitted in an inner pin hole formed in each of the external gears and capable of synchronizing with a rotation component of the external gear. In the planetary gear mechanism, a plurality of external gears processed using the same processing machine are eccentric in the same direction to form an external gear group, and the external gears in the external gear group are processed. The above object is achieved by incorporating the internal gear into the internal gear in a state where the rotation directions are shifted from each other based on the state.

The inventor of the present invention overturned the conventional idea of canceling each angle transmission error by incorporating a plurality of external gears in different eccentric directions, and referred to a plurality of external gears having substantially the same tooth profile error as the same. "We focused on configuring the external gear group by incorporating it in the eccentric direction. Then, the phases of the rotation directions of the plurality of external gears are shifted from each other, thereby canceling each other's angle transmission error in the same group.

That is, if a plurality of external gears are considered collectively, one external gear functions as a group of external gears in terms of power transmission. It has the function of reducing the angle transmission error.

As a result, a high-precision rotation can be achieved without being basically limited by the difference in the number of teeth between the internal gear and the external gear, and without considering the eccentric direction of each external gear. Speed control, rotation phase control, and the like can be achieved in a self-contained manner by the external gear group.

In order to reduce the angle transmission error, it is necessary to efficiently cancel the angle transmission error among a plurality of external gears in the external gear group. Therefore, in the above invention, when at least N external gears in the external gear group are prepared, the number of teeth of the external gear group is set to a multiple of N, and the at least N external gears are set. It is preferable that the gear is incorporated into the internal gear in a state where the phases in the rotation direction are shifted from each other by 360 / N (degree). By doing so, the phase difference between them is distributed at equal intervals,
The angle transmission errors of the external gears are evenly distributed and effectively cancel each other out.

Incidentally, the angle transmission error is not determined only by the shape error of the external gear, but also includes the shape error of the internal gear meshing with the external gear and the shape error of the eccentric body inserted at the center of the external gear. It is considered including. Nevertheless, for example, an external pin-type internal gear that forms internal teeth by installing an external pin on the inner peripheral surface of the internal tooth frame, or a generally cylindrical (shaft) shape is used. The eccentric body or the like has a small shape error even if each is formed independently. Therefore, it can be considered that the angle transmission error depends to a large extent on the shape of the external gear.

However, in order to further reduce the angle transmission error, it is preferable to exclude the influence of the shape error of the internal gear and the eccentric body, and all the external gears in the external gear group are It is preferable to be incorporated with respect to the common eccentric body and internally mesh with the common internal gear. In this case, the angle transmission error between the plurality of external gears depends on the shape error of the external gear "almost completely". Therefore, if the above-mentioned invention is applied, the angle transmission error between the external gears can be extremely effectively achieved. Will be canceled.

Particularly preferably, at least three external gears in the external gear group are prepared, and further, the thickness of the external gear in the helical direction is W, and the pitch diameter of the external gear is D. In this case, the external gear is set to satisfy W / D ≦ 0.07.

In the above invention, since a plurality of external gears are incorporated in a state of being eccentric in the same direction, and the external gear group is made to function exactly the same as one conventional external gear in terms of power transmission, it is apparent that It may be understood as a useless (redundant) configuration, but it is not. That is, as in the above invention, the thickness of each of the plurality of external gears is made smaller than that of the conventional external gear, and the external gear group in which the external gears are integrated can exhibit the performance of about one conventional external gear. It is also possible to prevent the whole mechanism from being enlarged in the axial direction,
Further, each external gear can be easily manufactured by punching or the like using a relatively thin material. That is,
Regarding the power transmission capacity, the necessary amount is secured by the number of external gears, while the angle transmission error is greatly reduced,
Further, this is a very rational structure in which the manufacturing cost can be reduced.

It is preferable that a side surface of the external gear in the external gear group is in contact with a side surface of the adjacent external gear. In this case, since the axial deviation and vibration of the external gears are regulated by the mutual contact, the internal structure can be simplified.

In the above invention, the processing machine for the external gear is not particularly limited, but preferably, either a pressing machine or a cutting machine is used. The above-mentioned press working is most desirable for realizing high precision and low cost. In the case of press working, a plurality of gear materials may be punched together, but since the tooth profile of the external gear is always constant depending on the shape of the punch, each material is punched separately. The plurality of external gears may be manufactured. on the other hand,
In the case of a cutting machine, it is preferable to simultaneously process a plurality of gear materials in a state where a slight shift occurs due to each cutting process.

When machining the plurality of external gears, the inner pin hole into which the inner pin is inserted (this is also referred to as the inner roller hole when the inner pin is covered with the inner roller). Eccentric body hole into which the eccentric body is inserted.

The oscillating internal meshing planetary gear mechanism of the invention described above is not limited to the case having one external gear group. For example, a state in which a first external gear group and a second external gear group are prepared by forming at least two external gear groups, and the first and second external gear groups are eccentric in directions away from each other. May be incorporated into the internal gear. Further, it is not necessary that the entirety be constituted by an external gear group, and the present invention also includes a case where a conventional single external gear is partially incorporated alone.

[0039]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a reduction gear 100 employing a swinging internal meshing planetary gear mechanism according to a first embodiment of the present invention. Here, the first shaft is used as the input shaft, the second shaft is used as the output shaft, and the internal gear is fixed, so that the oscillating internally meshing planetary gear mechanism is applied as the "reduction mechanism".

The reduction gear transmission 100 has an input shaft 1 as a first shaft.
01 and an eccentric body 103a, 1
A first external gear group (group) 105a and a second external gear group (group) 105b that eccentrically oscillate and rotate with a phase difference of 360/2 (degrees) from each other via the first and second external gears 03b. An internal gear 110 internally meshing with each of the tooth gear groups 105a and 105b;
And an output shaft 102 that is a second shaft that can be synchronized with the rotation components of 5a and 105b. Although details will be described later, each of the external gear groups 105a and 105b includes a plurality of external gears A.
1, A2 and A3 are laminated.

The eccentric bodies 103a and 103b are connected to the input shaft 10
1 are provided integrally with a predetermined phase difference (180 ° in this example). Each eccentric body 103a, 103
b is a common eccentric body hole 11 of the first and second external gear groups 105a, 105b via bearings 104a, 104b.
3a, 113b, so that the first and second external gear groups 105a, 105b have the eccentric bodies 103a,
It is rotatable with respect to 103b.

The first and second external gear groups 105a,
Each of 105b has a common inner roller hole (inner pin hole) 106
a and 106b are formed, and an inner pin 107 and an inner roller 10 provided on the output shaft 102 are provided for both of them.
8 are loosely fitted together in a contact state. This pin 10
The rotation of the output shaft 102 and the rotation of the output shaft 102 are synchronized by the interposition of the inner gear 7 and the inner roller 108. One end of the inner pin 107 is fixed or fitted to the output shaft 102, and the other end is held by a ring-shaped flange member 116.

The output shaft 102 and the flange member 116 are
In addition to the inner pins 107, they are connected by carrier pins 132. The carrier pin 132 loosely fits the common carrier pin holes 134a, 134b formed in the first and second external gear groups 105a, 105b in a non-contact state. Therefore, the carrier pin 132 does not serve to synchronize the rotation of each of the external gear groups 105a and 105b and the output shaft 102, but the flange member 116 and the output shaft 1
02 is firmly connected.

The first and second external gear groups 105a,
External teeth 109 having a trochoidal tooth shape or the like are formed on the outer periphery of 105b, and the external teeth 109 are internally meshed with the internal gear 110.

More specifically, the internal gear 110 has a cylindrical common internal tooth frame 120, a pin groove 122 formed on the inner peripheral surface of the common internal tooth frame 120, and a free fit in the pin groove 122. And an outer pin 111 to be installed, and the outer pin 111 is easily rotatably held. Also, common internal tooth frame 1
Numeral 20 is fixed to an external member (not shown).

When the input shaft 101 makes one rotation, the eccentric body 103
a and 103b make one rotation. This eccentric body 103a, 10
3b, the external gear group 105a, 10g
5b is trying to perform oscillating rotation around the input shaft 101, but its rotation is restricted by the internal gear 110, so that the external gear groups 105a and 105b are in contact with the internal gear and have a minute rotation. Rocking that includes By transmitting the minute rotation to the output shaft 102 via the inner pin 107, a desired deceleration can be obtained.

Next, the external gear groups 105a, 105
b will be described in detail. Since the first external gear group 105a and the second external gear group 105a have the same structure, the first external gear group 105a is used here.
Will be described only.

The first external gear group 105a is composed of three external gears A1, A2 and A3. The three external gears A1, A2, and A3 are manufactured by processing a gear material using the same processing machine, and specifically, are manufactured by punching using a press machine (not shown). The reason for the punching process is that the external gear A
1, the relationship between the thickness W in the tooth streak direction and the pitch circle diameter D of A2 and A3 is set to a relationship of W / D ≦ 0.07.

The three external gears A1, A2, and A3 are combined with their phases in the rotation direction shifted from each other to form a first external gear group 105a.
The phase here is based on the state at the time of press working, and since the same punch is used for the three external gears A1, A2, and A3, if the phases match, each external gear is used. The shapes of A1, A2, and A3 substantially match. That is, the first external gear group 105a is deliberately shifted from each other.

More specifically, the external gears A1, A2, A
The number of teeth of No. 3 is set to a multiple of three (here, 78), and these external gears A1, A2 and A3 are set to 120 degrees (360/3).
(Degrees). That is, the external gear A2 is laminated with a phase difference of 120 degrees with respect to the external gear A1, and the external gear A3 is further laminated with a phase difference of 120 degrees with respect to the external gear A2. If the number of teeth is set to a multiple of the number of external gears (here, all three of A1, A2, and A3) to be combined with a phase shift in the external gear group 105a, the external teeth will Match each other.

Further, the external gears A1, A2 and A3 are formed with an inner roller hole R, a carrier pin hole K and an eccentric body hole H. These are also formed simultaneously at the time of the press working, and the eccentric body hole H is formed at the center of the external gears A1, A2, A3, and the common eccentric body hole 113a is formed in a state where these are overlapped. (See FIG. 1).

The number of the formed inner roller holes R is equal to the number of the external gears (here, three) combined in each external gear A1, A2, A3 with the phase shifted in the external gear group 105a. An amount corresponding to a multiple is formed. Here, a total of nine pieces are formed. When these nine inner roller holes R are considered as three groups R1, R2, R3, they are formed at equal intervals in the circumferential direction with a phase difference of 120 (= 360/3) degrees. In this way, when the three external gears A1, A2, and A3 are stacked with the above-described phase difference (120 degrees), the inner roller holes R completely match each other, and the common state is maintained in the matched state. An inner roller hole 106a is formed (see FIG. 1).

Similarly, the carrier pin hole K is also provided for each external gear A
In A1, A2, and A3, the number of external gears (here, 3
(A sheet) is formed. Here, three carrier pin holes K are formed at equal intervals in the circumferential direction with a phase difference of 120 (= 360/3) degrees. In this way, when the three external gears A1, A2, A3 are laminated with the above-mentioned phase difference (120 degrees), each inner carrier pin hole K
Coincide with each other, and in this state, the common carrier pin hole 134
a is configured (see FIG. 1). Note that, in the present embodiment, the case where the carrier pin hole K is larger than the inner roller hole R is shown. For example, as shown in FIG. 3, the carrier pin hole K and the inner roller hole R are made the same size, These may be provided on the same pitch circle.

In this embodiment, the inner pin 107 is held at both ends by using the flange member 116. However, the present invention is not limited to this, and the inner pin 107 may be held at the output shaft 102 in a cantilever manner. . In that case, flange member 1
16. The carrier pin hole K and the carrier pin 132 become unnecessary.

As described above, the first external gear group 1
The second external gear group 105b is configured in exactly the same manner as described above. In this regard, a total of six external gears may be manufactured in advance by punching.

Further, here, the external gears A1, A2, A3
Is set to be a multiple of 3 and a multiple of 2. This is, as already shown in the conventional example,
This is because it is assumed that the first external gear group 150a and the second external gear group 150b are slid in the opposite direction (separation direction) by 180 degrees and incorporated into the internal gear 110. That is, it is assumed that the effect of “reduction of angle transmission error by incorporating a slide” shown in the conventional example can be obtained together. As a result, each external gear A1, A2, A
Since the difference between the number of teeth of the internal gear 110 and that of the internal gear 110 is required to be “2”, the number of teeth of the internal gear 110 is 80 (= 78 +
2), and the reduction ratio I is I = 2/78 = 1/39
Becomes

When focusing on the first external gear group 105a, three external gears A1, A2, and A3 are:
It will be incorporated in the common eccentric body 103a and the common internal gear 110. Further, each of the three external gears A1, A2, A3 is connected to the adjacent external gear A.
1, A2, and A3 are assembled in a state where their side faces are in contact with the side faces.

However, here, each of the external gears A1, A2,
A3 is not fixed to each other. This is because, if they are fixed to each other, a combination error due to the fixation occurs, which causes a new angle transmission error. That is,
As a whole, the external gear group 105a exhibits one power transmission function, which is achieved by each external gear A1, A
2, A3 can be said to be the result of functioning independently.

Returning to FIG. 1, the first and second external gear groups 105a and 105b are installed in the speed reducer 100, and are disposed between the end face 102a of the output shaft 102 and the end face 116a of the flange member 116. The axial movement is regulated by the inserted ring member 130. As a result, the eccentric bodies 103a, 1a of the external gears A1, A2, A3
03b is prevented from coming off.

Next, the operation of the first and second external gear groups 105a and 105b in the reduction gear transmission 100 will be described.

As shown in FIG. 4, the external gears A1, A
For each of A2 and A3, angle transmission errors a1, a2, and a3 occur during power transmission. This is because, as described above, the speed ratio of cyclic type tooth profiles such as the trochoid tooth profile used in this kind of oscillating internally meshing planetary gear mechanism is periodically shifted if there is an error in the center-to-center distance. .

Therefore, the first and second external gear groups 1
05a and 105b, three external gears A1,
A2 and A3 are combined in the same eccentric direction, and then combined with the phases in the rotation directions shifted from each other. As a result, the angle transmission errors a1, a2, and a3 occur at equal phase differences, and the same groups 105a, 105
The angle transmission errors a1, a2, and a3 of each other can be canceled in b. Moreover, each external gear group 105
Since a and 105b function as a single external gear as a whole, a sufficient power transmission function can be exhibited.

Further, each external gear group 105a, 10
Since the angle transmission error described above can be reduced in a state in which the gear is self-contained in FIG. 5b, the difference in the number of teeth between the internal gear 110 and the external gears A1, A2, A3 is not generally restricted.

Considering, for example, the first external gear group 105a, a plurality of external gears are incorporated in the common (1) internal gear 110 and the common (1) eccentric body 103a. The angle transmission error between A1, A2, and A3 completely depends on the shape error of each of the external gears A1, A2, and A3, and is extremely effective if combined at equal phase differences (120 degrees) as described above. Angle transmission error a
1, a2 and a3 cancel each other.

The external gear group 105a, 105b
In the above, the thickness of each of the external gears A1, A2, A3 is made smaller than that of the conventional external gear, so that they can be integrated to exhibit the performance of about one conventional external gear. Therefore, the transmission mechanism can be flexibly changed by appropriately changing the number and thickness of the mechanism while preventing the entire mechanism from being enlarged in the axial direction. In addition, since a relatively thin material is used, manufacturing costs can be greatly reduced by easily manufacturing each of the external gears A1, A2, and A3 by punching or the like.

In this embodiment, two external gear groups are provided, separated from each other and incorporated into the internal gear, and three external gears of each external gear group are provided. The case where the difference in the number of teeth between the gears and the external gears A1, A2, A3 is "2" is shown for convenience.

To summarize this situation, the number of teeth of the external gear,
The number of the inner roller holes R is as follows.

(1) Conditions under which phases can be shifted by 360/3 degrees to combine the external gears The number of teeth of the external gear: a multiple of 3 The number of internal roller holes R: a multiple of 3 (if necessary) Number of carrier pin holes K: multiple of 3

(2) Conditions for separating two external gear groups and incorporating them into the internal gear: Number of teeth of external gear: multiple of 2

Accordingly, as a result of the combination of the conditions (1) and (2), the following is obtained.

Number of teeth of external gear: multiple of 6 Number of inner roller holes R: multiple of 3 (if necessary) Number of carrier pin holes K: multiple of 3

If the number of external gears to be stacked with a phase shift within each group is N, the following general conditions are obtained.

Number of teeth of external gear: multiple of 2 * N Number of internal roller holes R: multiple of N (if necessary) Number of carrier pin holes K: multiple of N

Although the present embodiment has been described only for the case of a difference in the number of two teeth, the present invention is characterized in that the angle transmission error can be completely reduced in each internal gear group. The swinging internally meshing planetary gear mechanism has two external gears which have been considered difficult (here, two external gear groups), and the difference in the number of teeth between the internal gear and the external gear is "1". Applicable. In that case, the number of teeth of the external gear is set to an odd number, and one external gear group is eccentrically mounted in the separating direction while being rotated by 180 degrees with respect to the other external gear group. It is preferable to satisfy the following conditions.

(1) Assuming that the number of external gears to be incorporated with the phase shifted in each group is N, the phase is 360 /
Conditions that can be stacked by shifting N degrees Number of teeth of external gear: multiple of N Number of inner roller holes R: multiple of N (if necessary) Number of carrier pin holes K: multiple of N

(2) Even if one external gear group is rotated by 180 degrees with respect to the other external gear group, the common internal roller holes coincide with each other, and are eccentric in the separating direction and incorporated into the internal gear. Conditions that can be performed Number of teeth of external gear: odd number = (2n + 1), n (natural number) Number of inner roller holes R: even number (if necessary) Number of carrier pin holes K: even number

Therefore, the combined condition of the conditions (1) and (2) is as follows.

Number of teeth of external gear: N * (2n + 1), n
(Natural number) Number of inner roller holes R: multiple of 2 * N (if necessary) Number of carrier pin holes K: multiple of 2 * N

When the difference in the number of teeth is "1" as described above, the reduction ratio is doubled compared to the case of the difference in the number of teeth 2 shown in the present embodiment under the condition that the number of teeth of the external gear is the same. Becomes possible. Conversely, if an attempt is made to obtain the same reduction ratio as in the case of a difference in the number of two teeth, the number of teeth of the external gear can be set to one half, and the reduction gear can be made more compact.

The present invention is not limited to the case where the oscillating internal meshing planetary gear mechanism has two external gear groups, and may be one or three or more. Further, the external gear group of the present invention may be used in combination with a conventional (single) external gear.

In this embodiment, in each external gear group, only the case where all the external gears are stacked with the phases shifted is shown, but the present invention is not limited to this, and a part of many external gears is included. (Plural) external gears may be shifted in phase.

Further, in the present embodiment, a case where a plurality of external gears in each external gear group are in contact with each other has been described. However, the present invention is not limited to this. Are provided, and they also include the case where they function as an external gear group as a whole. Furthermore,
For example, the case also includes the case where the external gears of the first external gear group and the external gears of the second external gear group are alternately arranged.

In this embodiment, the internal gear is fixed, the first shaft is used as the input shaft, and the second shaft is used as the output shaft. However, the second shaft is fixed, the first shaft is used as the input shaft, and the internal gear is used. May be used as an output shaft to form a reduction gear. Further, it is also possible to configure a speed increasing device by reversing these inputs and outputs.

As described above, the first and second embodiments have been described. However, as long as they do not depart from the gist of the present invention, there are also embodiments in which these parts are appropriately combined. There are various embodiments other than the above embodiments. In addition, the description (function / shape) of the member that appears in the full text of the specification
Is merely an example, and the present invention is not limited to these descriptions.

[0086]

According to the present invention, the vibration (angle transmission error) in the rotating direction can be reduced while maintaining the high reduction ratio characteristic of the oscillating internal meshing planetary gear mechanism. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a reduction gear to which a swinging internally meshing planetary gear mechanism according to an embodiment of the present invention is applied.

FIG. 2 is a sectional view taken along the line II-II of FIG.

FIG. 3 is a sectional view showing another example of the reduction gear transmission.

FIG. 4 is a diagram schematically showing an angle transmission error of the speed reducer.

FIG. 5 is a cross-sectional view showing a reduction gear adopting a conventional swinging internally meshing planetary gear mechanism.

6 is a sectional view taken along the line VI-VI in FIG. 5;

FIG. 7 is a diagram showing an angle transmission error of the oscillating internal meshing planetary gear mechanism.

FIG. 8 is a schematic diagram showing a meshing state of a swinging internally meshing planetary gear mechanism having a difference in the number of teeth of “2”;

[Explanation of symbols]

 100, 200: Reduction gear 101: First shaft 102: Second shaft 105a: First external gear group 105b: Second external gear group 106: Common internal roller hole 107: Internal pin 108: Internal roller 110: Internal tooth Gear 111 ... Outer pin 120 ... Common inner tooth frame 122 ... Pin groove

Claims (6)

[Claims] A first shaft, an external gear that oscillates and rotates with respect to the first shaft via an eccentric body, an internal gear that meshes internally with the external gear, and the external gear And a second shaft having an inner pin loosely fitted in an inner pin hole formed in each of the first and second gears and capable of synchronizing the rotation component of the external gear. An external gear group is formed by eccentrically arranging a plurality of the external gears processed in the same direction, and the rotation direction phase of the external gears in the external gear group is set based on a processing state. A swinging internally meshing planetary gear mechanism, wherein said planetary gear mechanism is incorporated in said internal gear in a state shifted from each other. 2. The external gear group according to claim 1, wherein when at least N external gears in the external gear group are prepared, the number of teeth of the external gear group is set to a multiple of N, and A rocking internally meshing planetary gear mechanism, wherein N external gears are incorporated in the internal gear in a state where the phases in the rotation direction are shifted from each other by 360 / N (degrees). 3. The external gear group according to claim 1, wherein all of the external gear groups in the external gear group are incorporated into a common eccentric body and internally meshed with a common internal gear. A swinging internally meshing planetary gear mechanism characterized by the following. 4. The external gear according to claim 1, 2 or 3, wherein at least three external gears in the external gear group are provided, and further, the external gear has a thickness in the direction of the tooth rim W, Wherein the external gear is set to satisfy W / D ≦ 0.07, where D is the pitch circle diameter of the oscillating internal meshing planetary gear mechanism. 5. The first external gear group and the second external gear group according to claim 1, wherein the first external gear group and the second external gear group are prepared by configuring at least two external gear groups. A swinging internally meshing planetary gear mechanism, wherein the second external gear group is incorporated in the internal gear in a state where the second external gear group is eccentric in a direction away from the gear group. 6. A first shaft, an external gear that oscillates and rotates eccentrically with respect to the first shaft via an eccentric body, an internal gear that meshes internally with the external gear, and the external gear. And a second shaft having an inner pin loosely fitted in an inner pin hole formed in each of the first and second gears, the second shaft being capable of synchronizing with the rotation component of the external gear. In the reduction method, a plurality of the external gears are processed by using the same processing machine, and the plurality of external gears are eccentric in the same direction to form an external gear group. Wherein said external gear is incorporated into said internal gear in such a manner that the rotation direction phases thereof are shifted from each other with respect to a machining state.