JP2002156011A - Speed increasing and reducing gear of inner gearing planetary gear structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a relative slip velocity of a mesh point according to a rational idea. SOLUTION: This speed increasing and reducing gear 120 of a rocking inner gearing planetary gear structure is provided with an external tooth gear 105 having a tooth form containing a trochoid curve, and an internal tooth gear 110 internally meshing with the external tooth gear 105. The shapes of the external tooth gear 105 and the internal tooth gear 110 are set to satisfy the relationship r1<(I+1)*e<r2 where I is the speed reducing ratio in the case of using the rocking inner gearing planetary gear structure as a speed reducing mechanism, e is the amount of eccentricity of eccentric rocking movement, r1 is the tip radius of the internal tooth gear, and the dedendum circle radius thereof is taken as r2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an external gear having a tooth profile including a trochoidal curve, and an acceleration / deceleration of a oscillating internal meshing planetary gear having an internal gear internally meshed with the external gear. More particularly, the present invention relates to a technique such as a tooth profile structure of internal teeth and external teeth.

[0002]

2. Description of the Related Art Conventionally, such a type of speed increasing / decreasing gear having an oscillating internal meshing planetary gear has a function capable of realizing from a low increase / reduction ratio to a high increase / reduction ratio with a small number of reduction stages. Widely known. In this oscillating internal gear planetary gear structure, the external gear and the internal gear relatively eccentrically oscillate, thereby causing relative rotation between the two gears from the restraint of the internal meshing state, and the eccentricity. Power is transmitted at an increasing / decreasing ratio depending on the rotational speed difference between the oscillating motion and the relative rotation.

FIG. 7 shows a conventional speed reducer 20 in which the oscillating internally meshing planetary gear structure is incorporated so as to have a speed reducing function.
Is shown. The reduction gear 20 includes a first shaft (in this case, an input shaft) 1 and an eccentric body 3 that rotates by rotation of the first shaft 1.
a, 3b and bearings 4a,
4b, which is mounted via an eccentric rotation.
The external gears 5a, 5b, the internal gear 10 internally meshing with the external gears 5a, 5b, and the external gears 5a, 5b
(In this case, an output shaft) 2. In this conventional example, two external gears 5a, 5b
Is a double-row type, but of course, it may be a single-row type comprising one external gear.

[0004] The eccentric bodies 3a and 3b are fitted to the input shaft 1 with a predetermined phase difference (180 ° in this example). As shown in FIG. 8, the eccentric bodies 3a and 3b
Each is eccentric with respect to the input shaft 1 (center O1) by the amount of eccentricity e (center O2).

The external gears 5a and 5b have inner roller holes 6 formed therein.
a, 6b, a plurality of inner roller holes 6a,
The inner pin 7 and the inner roller 8 are fitted (with play) into 6b. The inner pin 7 and the inner roller 8 are
This corresponds to the “member for extracting only the rotation component of the external gear”. The inner pin 7 is fixed or fitted to the flange of the output shaft 2.

[0006] On the outer periphery of the external gears 5a and 5b, there are provided external teeth 9 having a trochoid tooth profile (specifically, an epitrochoid parallel curve tooth profile is employed in this conventional example).
The external gear 9 is internally meshed with the internal gear 10 fixed to the casing 12.

The internal gear 10 includes a cylindrical internal tooth frame 32 and a plurality of external pins 34 installed on the inner peripheral side of the internal tooth frame 32.
And. Specifically, an axial pin groove 33 is formed on the inner periphery of the internal tooth frame 32, and the outer pin 4 is provided in the pin groove 33. The tooth surface of the internal teeth 11 is formed by the outer peripheral surface (portion exposed inside) of the outer pin 32.

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,
Although the external gears 5a and 5b try to rotate around the input shaft 1, their free rotation is restricted by the meshing state with the internal gear 10, so that the external gears 5a and 5b
An eccentric oscillating motion based on 1 and a slight rotational motion (due to a difference in the number of teeth between the internal teeth 11 and the external teeth 9) are performed.

Now, for example, the number of teeth of the external gears 5a and 5b is set to n.
(In the illustrated example, n = 35), the internal gear 10
Is n + 1, the difference N between the teeth is 1.
For this reason, the external gears 5 a and 5 b are one-to-one with respect to the internal gear
It will shift (rotate) by the amount of the teeth. This means that one rotation of the input shaft 1 has been reduced to 1 / n rotation of the external gears 5a and 5b. The external gears 5a, 5b
Is opposite to the rotation on the input side.

[0010] The rotation of the external gears 5a, 5b
The oscillating component is absorbed by the gap between the a and 6b and the inner pin 7 (the inner roller 8), and only the rotation component is transmitted to the output shaft 2 via the inner pin 7, so that the reduction of the reduction ratio I is achieved. Is done. In general terms, when the number of external teeth is z1 and the number of internal teeth is z2, in this input / output relationship, the reduction ratio I = (z1) / (z2-z1).

In the above structure, the output is taken out through the inner pin 7 and the internal gear is fixed. However, the output is taken out from the internal gear and is used as the output shaft in the above example. By fixing the member
It is possible to construct a speed reducer. Furthermore, in these structures, by reversing the input / output relationship,
A "speed increaser" can also be configured. In short, external gear 5
A predetermined acceleration / deceleration function is to be obtained by utilizing the relative rotation between the internal gear 10 and the internal gear 10. Further, in this conventional example, the case where the tooth number difference N is 1 is shown, but it is possible to set the tooth number difference to one or more. Regarding the difference of one or more teeth, Japanese Patent Application Laid-Open No.
Since it is detailed in Japanese Patent Publication No. 050394, etc., the description here is omitted.

[0012]

The trochoid parallel curve used in the tooth profile of the external gears 5a and 5b has a feature of reducing the interference between the external teeth 9 and the internal teeth 11, but on the other hand, has the feature of reducing the interference. Since acceleration and deceleration are performed using relative rotation with the tooth gear 10, the relative sliding speed of the mesh point on the tooth surface tends to increase. This "high-speed sliding of the mesh point" causes wear of the tooth surface and shortens the service life, and further reduces power transmission efficiency and increases noise.

In order to solve this problem, an outer pin 34 which is installed in a rotatable state is employed as the inner teeth 11, and the outer pin 34 rotates to absorb the slip speed of the meshing point. (Reduce). However, the effect of reducing the sliding speed by the outer pin 34 has a certain limit, and the rotation of the outer pin 34 causes problems such as vibration and noise, and the problem is not solved fundamentally.

Various other efforts have been made in the past to reduce the sliding speed. However, in the first place, the trochoid curve is applied to the external teeth 9, and the external teeth 9 and the internal teeth 1 are applied.
Since the correlation with the slip speed of No. 1 has not been clarified, it is considered that the various parameters such as the tooth profile were set empirically after many experiments. Therefore, their specifications are poor on theoretical grounds (even if the sliding speed can be reduced to some extent), and to the knowledge of the present inventors, the existence of the present invention A swinging internal meshing planetary gear structure that is set at a truly optimal specification value as assumed is not real.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and, based on obvious theoretical grounds, has shown a drastic reduction in the relative sliding speed of the meshing surfaces of an internal gear and an external gear. ,
It is intended to increase transmission efficiency, reduce noise and extend the life of gears, and further improve transmission torque.

[0016]

According to the present invention, there is provided an external gear having a tooth profile including a trochoid curve, and an internal gear which is internally meshed with the external gear, wherein the external gear and the internal gear are provided. A relative rotation corresponding to the difference in the number of teeth is generated between the two gears by relatively eccentric oscillating motion, and power is increased at a speed increase / reduction ratio depending on a rotational speed difference between the eccentric oscillating motion and the relative rotation. In a speed increasing / reducing device having an oscillating internal meshing planetary gear structure for transmitting, the reduction ratio when the oscillating internal meshing planetary gear structure is used as a reduction mechanism is I, and the eccentric amount of the eccentric oscillating motion is e. If the radius of the addendum circle of the internal gear is r1 and the radius of the root circle is r2, then r1 <(I + 1) * e <r2
The above-mentioned object is achieved by setting the shapes of the external gear and the internal gear so as to satisfy the following relationship.

In this oscillating internally meshing planetary gear, a trochoid curve is employed for the external teeth of the external gear in order to reduce interference with the internal gear as much as possible. In general, when the trochoid curve is applied to the external teeth, the sliding speed of the tooth surface at the mesh point increases, in other words, by sliding the mesh point at a high speed with the external teeth of the trochoid curve, a smooth and interference-free It is believed that a transmission structure is obtained.

However, the present inventor has further studied the shapes of the external gear and the internal gear. As a result, if the conditions as in the present invention are satisfied, the merit of the tooth shape including the trochoid curve is lost. It has been found that the slip speed at the meshing point can be kept extremely low within a reasonable range. The specific operation will be described in detail in “Embodiments of the Invention”.

According to the speed increasing / decelerating device according to the present invention, it is possible to have a meshing point at which the slip speed becomes zero (or almost zero) on the tooth surface of the external gear. The sliding speed can be extremely low.

In particular, the maximum efficiency meshing point at which the reaction force received from the internal gear can be effectively converted into torque on the tooth surface of the external tooth (specifically, the common point at the meshing point of the internal tooth surface and the external tooth surface) The meshing point when the normal is most distant from the center of the internal gear) is referred to as the “region where the slip speed is extremely low”.
Since it is possible to include the inside of the motor, the slip speed of the meshing point, which plays an important role in power transmission, is reduced, and power can be transmitted with higher efficiency and lower noise than before.

As described above, since the slip speed at the meshing point can be set low, the wear amount of both the external teeth and the internal teeth is reduced, so that the service life is extended. For example, when the internal teeth of the internal gear are constituted by a plurality of external pins, the wear and fatigue of the external pins are reduced, and the life is dramatically extended. The main purpose of this external pin type internal gear is to absorb high-speed slippage of the tooth surface by rotating (rotating) each of the external pins. Since the internal teeth are reduced, it is possible to integrally form the internal teeth, thereby reducing manufacturing and assembly costs.

When the above invention is applied to the external pin type internal gear, specifically, the internal gear is
The internal gear includes a cylindrical internal tooth frame and a plurality of external pins installed on the inner peripheral side of the internal tooth frame and forming a tooth surface of the internal tooth with its own outer surface. Radius r1
Is the radius of a circle formed by connecting the radially inner ends of the internal gear frame in the plurality of outer pins, and the root radius r2 of the internal gear is equal to the radius of the plurality of outer pins. ,
The radius may be the radius of a circle formed by connecting the radially outer ends of the internal tooth frame. This is because each internal tooth is constituted by the entire outer pin.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a gear analyzing process performed by the present inventors will be specifically described.

FIG. 1 shows an analytical model of a general swinging internally meshing planetary gear structure.

In this analysis model, an external gear A (center S) having a tooth shape including a trochoid curve is in mesh with an internal gear B (center O). The external gear A and the internal gear B are eccentric by an eccentric amount e, and the center O of the internal gear B is located inside the periphery of the external gear A. This is a feature of the oscillating internal meshing planetary gear structure, that is, the international patent classification F1.
This is a feature belonging to 6H1 / 32.

If the internal gear B is fixed and rotational power is input to the external gear A, the external gear A meshes with the internal gear B and eccentrically oscillates (see arrow L). ).
The radius of rotation of this eccentric oscillating motion is the amount of eccentricity e. As a result, a rotation delay (relative rotation: see arrow U) occurs in the external gear A due to the difference in the number of teeth from the internal gear B. That is,
When viewed from the internal gear B side, the external gear A rotates (reverse) by an amount corresponding to the “relative rotation”. If this relative rotation is taken out by a carrier (not shown), it is possible to obtain an output rotation that is reduced with respect to the input rotation.

Therefore, if the eccentric oscillating movement L on the input side is compared with the relative rotation U on the output side, it can be said that power is transmitted at the reduction ratio I corresponding to the ratio of the rotational speeds. In addition,
By reversing the input / output relationship, it functions as a gearbox, and the gear ratio is 1 / I.

The reduction ratio I can be expressed as I = (z1) / (z2-z1) from the number z1 of teeth of the external gear A and the number z2 of teeth of the internal gear B. Therefore, assuming that the rotational angular velocity of the input rotational power represented by the arrow L is ωi, the rotational angular velocity ωu of the output rotational power represented by the arrow U is ωu = −ωi / I. In addition, minus signifies reverse rotation.

Now, the center X of the internal gear B becomes X-
Considering the Y coordinate, the coordinates of the center S of the external gear A are (xs, y
Set to s). When the time t has elapsed, the point S moves eccentrically about the origin O and moves to a point S1 (xs1, ys1). The relationship between these two points S and S1 can be expressed as follows.

[0030]

(Equation 1)

That is, A (ωi · t) is a rotation matrix, which means that the rotation has been made by the phase (ωi · t) around the origin.

Here, similarly, in the XY coordinate system,
Considering the arbitrary meshing point C (x, y) with the internal gear B on the tooth surface of the external gear A, if the eccentric oscillating motion of the external gear A is neglected, the center S is used as a reference. Point C
Is rotating, the point C moves to the virtual point Ca (xa, ya) after the time t has elapsed. Therefore, considering the external gear A as a reference, the relationship between these two points C and Ca can be expressed as follows.

[0033]

(Equation 2)

However, in reality, the external gear A is eccentrically oscillating. Thus, point C is actually point Cb (xb,
yb), but the above equation (1),
By combining (2), the relationship between the meshing point C and the point Cb "based on the origin O" is expressed.

[0035]

(Equation 3)

Here, in order to consider the instantaneous "movement" of the point C with respect to the origin O, that is, with respect to the internal gear B, the equation (3) is differentiated with respect to time t. Substituting = 0 gives:

[0037]

(Equation 4)

This means the instantaneous moving speed of the mesh point C. As is clear from the equation (4), the meshing point C is set at the instantaneous center P ((I + 1) xs, (I + 1) ys
), It turns out that it is rotating at the rotational angular velocity ωi / I. At this time, if it is considered that the internal gear B is fixed, this speed is the sliding speed of the external gear A with respect to the internal gear B at the mesh point C. The instant center P exists on the extension of the line segment OS, and the absolute distance from the point O is (I + 1) * e.

The present inventor has further applied the above analysis to specifically analyze the motion state of the meshing point C in the conventional (general) oscillating internally meshing planetary gear structure of a speed increasing and reducing device. . FIG. 9 shows the result. In addition, the symbol (A,
C, S, P) are used in the same sense as in the above points.

This gearbox has a structure in which a plurality of external teeth of the external gear A mesh simultaneously with the internal gear. Each meshing point Cn (n = 1, 2, 3,...) Of each external tooth is all rotating at the rotational angular velocity ωi / I about the instantaneous center P. Accordingly, the longer the length of each virtual arm En connecting each meshing point Cn and the instant center P, the greater the sliding speed.

As is clear from FIG. 9, in the conventional speed reducer, all the meshing points Cn are provided with virtual arms En having a certain length.
It can be seen that the mesh point Cn has a certain amount of sliding speed "always". As a result, the tooth surface is constantly worn at each meshing point Cn, and further noise is generated.

Next, a consideration will be given to the transmission torque when this accelerating / decelerating device is used as a speed reduction mechanism, particularly when the external gear A is an output element.

Each external tooth of the external gear A receives a reaction force Fn from the internal teeth at each meshing point Cn. The direction of the reaction force Fn is a common normal direction to the tooth surface, that is, the same direction as the virtual arm En. Because of the resultant force of the respective reaction forces Fn, the reaction torque from the output-side counterpart machine or the like is resisted.
A virtual torque arm Tn corresponding to the distance between each virtual arm En and a reaction force Fn corresponding to the virtual torque arm Tn
With the product (Tn · Fn). Therefore, the transmission torque K of the speed reducer can be expressed as K = Σ (Tn · Fn),
In order to increase the transmission torque, it is important to set the length of the virtual torque arm Tn as long as possible.

The meshing point Cn on the tooth surface of the external teeth where the meshing reaction force Fn with the internal gear B can be effectively converted into torque is when the length of the virtual torque arm Tn is the longest. That is, the mesh point Cn when the virtual torque arm Tn is at a right angle to the straight line OP. This point plays the most important role in power transmission, and is called the maximum efficiency mesh point M (here, mesh point C3).
I will call it. Even at the maximum efficiency mesh point M,
Heretofore, the embodiment of the present invention will be described in detail, which is considered to be a factor that lowers the transmission efficiency due to frictional resistance or the like because it has a high sliding speed in the past.

FIG. 2 shows the external gear 105 of the speed increasing / reducing device 120 having the oscillating internal meshing planetary gear structure according to this embodiment.
2 shows the tooth profile structure of the internal gear 110. The structure of the oscillating internal meshing planetary gear is substantially the same as that of the conventional speed reducer 20 shown in FIGS. 7 and 8, and the same or similar members and parts are attached to the speed reducer 20. The same reference numerals and lower two digits are used, and the detailed illustration of the whole drawing and the structure / action will be omitted.

External gear 105 in the speed increasing and reducing device 120
Has external teeth 130 having a tooth shape including a trochoid curve (specifically, an epitrochoid parallel curve). An internal gear 110 is internally meshed with the external gear 105, and the external gear 105 and the internal gear 110 relatively eccentrically oscillate (angular velocity ωi), so that there is a gap between the two gears. Relative rotation (angular velocity ωu) is generated. Therefore, power can be transmitted at the increase / decrease ratio I corresponding to the ratio of the number of rotations of the eccentric oscillating motion and the relative rotation.

The tooth profile of the internal teeth 111 of the internal gear 110 is, as shown in an enlarged view in FIG. 3, arcuate tooth-shaped portions R, R at both ends which are engaged with the external teeth 130, and an intermediate tooth-shaped portion Q. (This portion serves as a relief for preventing interference with the external teeth 130).

Therefore, the arcuate tooth profile P which is the basis of the tooth profile
The power is transmitted by the meshing point C in.

When this oscillating internal meshing planetary gear structure is used as a reduction mechanism, the reduction ratio I is z2, the number of the internal teeth 111 of the internal gear 110, the external teeth 130 of the external gear 105.
Assuming that the number of teeth is z1, it can be expressed as follows.

I = z1 / (z2-z1)

Here, in the oscillating internal meshing planetary gear structure of this embodiment, the eccentric amount of the eccentric oscillating motion, which is the distance between the center S of the external gear 105 and the center O of the internal gear 110, is e. R1 <(I + 1) * e, where r1 is the radius of the addendum circle H and r2 is the radius of the root circle W of the internal gear 110.
The tooth profile of each internal gear 110 and external gear 105 is set in a state where the relationship of <r2 is satisfied.

More specifically, as has already been analyzed in detail, in the oscillating internal meshing planetary gear structure, (I +
1) * e is the instantaneous center P of the sliding movement of each meshing point Cn. As shown in an enlarged manner in FIG.
Is set in the range from the tip circle H to the root circle W of the internal gear 110.

Considering the mesh point Cn between the internal teeth 111 and the external teeth 130, it is natural that all the mesh points Cn on the external teeth 130 are within the range from the tip circle H to the root circle W. It has become. At this moment, each of these meshing points Cn is rotating around the instantaneous center P at each speed ωi / I. Therefore, the longer the virtual arm En connecting all the mesh points Cn and the instantaneous center P is, the higher the sliding speed of the mesh point Cn is.

As is apparent from FIG. 4, in the speed increasing / decreasing device 120, there are a plurality of meshing points Cn in which the length of the virtual arm En is extremely short in a range close to the instantaneous center P.
That is, the sliding speed of these mesh points Cn becomes extremely low.

When the external gear 105 rotates, the external gear 1
05 also moves (relative to the center O of the internal gear 110), so that the instantaneous center P located on the extension of the points O and S
Will also move. Therefore, the set position of the point P is r1
If it is adjusted appropriately within the range of ~ r2, the instant center P is
1 and the instantaneous center P and the mesh point C
It is also possible to match n (this does not necessarily have to be set as such). Since the length of the virtual arm En is "zero" at the mesh point Cn (this is defined as the zero mesh point P1) which coincides with the instant center P at this moment, the slip speed is also "zero". That is, the area near the zero mesh point P1 in each external tooth 130 is:
Very low sliding speeds including "zero" can be achieved.

By the way, referring to FIG.
And the entire meshing point Cn of the internal gear 110,
As in the related art, there is also an engagement point Cn where the virtual arm En has a predetermined length and has a predetermined sliding speed. However, the maximum efficiency mesh point M which greatly contributes to the transmission of power (specifically, the mesh point Cn when the line segment OP is orthogonal to the virtual arm En, here C2: see FIG. 4) Naturally approaches the instant center P side, and thus the length of the virtual arm En becomes extremely short. As a result, the slip speed at the maximum efficiency mesh point M is significantly reduced, so that the transmission efficiency is improved and the transmission noise can be reduced. In other words, it is possible to extremely effectively (rationally) suppress abrasion or the like in a region that plays an important role in transmitting power on the tooth surface.

The transmission torque K is determined by the reaction force Fn that each external tooth 130 receives from the internal tooth 111 at each meshing point Cn and the center O
To the sum of the product (Tn · Fn) with the virtual torque arm Tn corresponding to the distance of each virtual arm En (K = Σ (Tn · F
n)), but since the instantaneous center P is set at a position distant from the point O, the length of the virtual torque arm Tn can also be set significantly longer. Most noticeable. As a result, the transmission torque can be increased even if the tooth surface strength is equivalent to the conventional one.

FIG. 5 shows the result of comparison between the sliding speed of the external teeth 130 of the speed reducer 120 of this embodiment (solid line A) and the sliding speed of the external teeth of the conventional speed reducer 20 (dotted line B). Show.
In the past, a predetermined sliding speed was always present in all regions of the external teeth. However, in the present speed increasing / decelerating device 120, the sliding speed on the valley side is drastically reduced, and the sliding speed is temporarily reduced at the zero mesh point P1. Becomes "zero", and then the sliding speed rapidly increases. However, the maximum efficiency mesh point M (or its vicinity) which plays a significant role in power transmission is located in the extremely low speed region 90 immediately before the slip speed increases. Therefore,
It can be seen that the slip speed is much lower than the maximum efficiency mesh point M in the conventional speed reducer 20.

From the above results, in the speed reducer 120 according to the present embodiment, the slip speed of the meshing point Cn on the “tooth tip” side of the external teeth 130, which is not so important for power transmission, is ignored. It can be seen that the rational configuration is such that the slip speed at the important meshing point is drastically reduced.

In this embodiment, the internal gear 1
The case where ten internal teeth 111 are formed integrally is shown. This is because the relative slip speed on the tooth surface that plays an important role in power transmission is reduced, and as a result, the necessity of absorbing the slip speed on the inner teeth 111 side is reduced. Therefore, manufacturing and assembly costs of the internal gear 110 are also reduced.

However, an internal gear having an outer pin structure may be employed. In this case, as shown in a partially enlarged view in FIG. 6, the internal gear 110 is
32 and a plurality of outer pins 134 installed on the inner peripheral side of the inner tooth frame 132 and forming the tooth surface of the inner tooth by its outer surface.
May be provided. In this case, the addendum radius r1 of the internal gear 110 is the radius of a circle 136 formed by connecting the radially inner ends 134A of the internal gear frame 132 in the plurality of outer pins 134. The root radius r2 is
This is the radius of a circle 138 formed by connecting the radially outer ends 134B of the inner tooth frame 132 in the plurality of outer pins 134. Therefore, the instant center P may be set from these values r1 and r2.

According to the present embodiment, the relative slip speed on the tooth surface which does not contribute much to the power transmission cannot be reduced. However, by adopting the internal teeth by the outer pins 134, the slip at this portion can be absorbed.

[0063]

According to the present invention, it is possible to drastically reduce the slip speed at an important meshing point based on a rational idea, so that it is possible to improve power transmission efficiency and reduce noise. . Further, the life of the gear can be extended.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an analytical model of an oscillating internal meshing planetary gear structure in the process of devising the present invention.

FIG. 2 is a cross-sectional view showing a speed increasing and reducing device having an oscillating internal meshing planetary gear structure according to an embodiment of the present invention.

FIG. 3 is a partially enlarged view showing the tooth profile of the external teeth and the internal teeth of the speed increasing and reducing device.

FIG. 4 is a partially enlarged view showing a meshing state of external teeth and internal teeth of the speed increasing / reducing device.

FIG. 5 is a diagram showing an analysis result of a slip speed on the tooth surface of the external teeth of the same speed reducer.

FIG. 6 is a partially enlarged cross-sectional view of the same speed increasing / reduction device, in which an internal gear with an outer pin is applied.

FIG. 7 is an overall cross-sectional view showing a conventional speed increasing / reducing device having a swinging internally meshing planetary gear structure.

8 is a sectional view taken along line VIII-VIII of FIG. 7;

FIG. 9 is a diagram showing the meshing state of the external teeth and the internal teeth in the same speed reducer.

[Explanation of symbols]

 105: external gear 110: internal gear 111: internal gear 120: speed increasing / decelerating gear 130: external gear 132: internal gear frame 134: external pin

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Atsushi Takahashi 6-1, Asahimachi, Obu City, Aichi Prefecture Sumitomo Heavy Industries Machinery Co., Ltd. Nagoya Works F-term (reference) 3J027 FA12 FA37 FC07 FC12 GC02 GC24 GD04 GD08 GD12 GE11 GE21 3J030 AA00 BA01 BB06 BB11

Claims (2)

[Claims] 1. An external gear having a tooth profile including a trochoid curve, and an internal gear internally meshed with the external gear, wherein the external gear and the internal gear relatively eccentrically swing. As a result, a relative rotation corresponding to the difference in the number of teeth is generated between the two gears, and an oscillating internally meshing planet that transmits power at an increasing / decreasing ratio depending on the rotational speed difference between the eccentric oscillating motion and the relative rotation In the speed increaser / reducer having a gear structure, when the oscillating internally meshing planetary gear structure is used as a reduction mechanism, the reduction ratio is I, the eccentric amount of the eccentric oscillating motion is e, and the addendum circle of the internal gear is When the radius is r1 and the root radius is r2, the shapes of the external gear and the internal gear are set so as to satisfy a relationship of r1 <(I + 1) * e <r2. A speed increasing and reducing gear with a meshing planetary gear structure. 2. A plurality of internal gears according to claim 1, wherein said internal gear is provided on a cylindrical internal tooth frame and an inner peripheral side of said internal tooth frame, and forms a tooth surface of the internal teeth by its outer surface. The internal gear has a tip circle radius r1 which is a radius of a circle formed by connecting the radially inner ends of the internal tooth frames of the plurality of external pins. In both cases, the root radius r2 of the internal gear is
The speed increaser / reducer of the internally meshing planetary gear structure, wherein each of the plurality of outer pins has a radius of a circle formed by connecting radially outer ends of the inner tooth frame.