JPH0557461B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides an internal gear having a circular arc tooth profile made of a pin or a combination of a pin and a roller, and an external gear tooth profile having a trochoid shape made of an epitrochoid parallel curve. The external gear has a circular tooth profile or an arc tooth profile, and an inner pin or an inner pin and an inner roller are loosely fitted to the external gear, and the external gear is oscillated by the rotation of an eccentric body fitted to the external gear. This invention relates to an improvement of a planetary gear speed reducer that dynamically rotates and internally meshes both the inner and outer gears to decelerate or speed up the input rotation and output the output. This invention relates to an improvement in an averaging inner pin support ring.

(Prior Art) Various reduction gears using internally meshing planetary gear mechanisms have been proposed. Among these reducers, the internal gear has a circular arc tooth profile made of a pin or a combination of a pin and a roller, and the external gear has a trochoid tooth profile made of an epitrochoid parallel curve. The pin and inner roller are loosely fitted, and the rotation of the eccentric body fitted to the external gear causes the external gear to oscillate and rotate, causing both the internal and external gears to engage internally to decelerate the input rotation and output. The planetary gear reducer is famous as the "cyclo reducer" (registered trademark). And this "cyclo reducer"
Because it is capable of transmitting large torque and has a large reduction ratio, it is used as a variety of reduction mechanisms.

An example of a known "cyclo reducer" will be explained below with reference to FIGS. 3 and 4.

FIG. 3 is a sectional view showing an example of a known planetary gear reducer, and FIG. 4 is a sectional view taken along line BB in FIG. 3.

An eccentric body 3 is provided on the input rotating shaft 1.
A key groove 4 is formed in the hollow portion of the eccentric body 3, and a key 4A is fitted into the groove 4. The external gear 5 is fitted onto the eccentric body 3 via rollers 6. This external gear 5 has external teeth 7 having a trochoidal tooth profile on its outer periphery. Further, the internal gear 8 also serves as an outer casing, and is fixed in this example. The internal gear 8 has an arcuate tooth profile consisting of an external pin 9 that internally meshes with the external gear 5. The outer pin 9 may have a structure in which an outer roller is loosely fitted therein. The external gear 5 has an internal pin hole 10.
is formed, and an inner pin 11 is formed in the inner pin hole 10.
is loosely fitted. An inner roller 12 is loosely fitted around the outer periphery of the inner pin 11, and one end of the inner pin 11 is tightly fitted into an inner pin holding flange 13. Note that the inner roller 12 can be omitted.
The inner pin holding flange 13 is integrally formed with the output shaft 2.

The internal gear 8 is held between covers 14 and 15 from both sides, and is fixed with bolts 16. The output side shaft 2 and one cover 14
Two bearings 17 are provided at intervals between them.

In addition, in the above-mentioned known example, the internal gear 8 is fixed and the output is taken out from the output side shaft 2, but on the contrary, the output side shaft 2 is fixed and the rotation of the internal gear 8 is taken out as the output. It can also be a structure.

(Problems to be Solved by the Invention) However, the above planetary gear speed reducer has the following problems.

In other words, since the structure is such that the load fluctuations occurring in the deceleration mechanism are cantilever-supported by the two bearings 17, in order to increase the stability of the support, it is necessary to make the Y section long and the X section as short as possible. It becomes necessary. However, since it is difficult to shorten the X interval, the Y interval must be lengthened.
As a result, the axial length becomes longer.

Furthermore, in the planetary gear reducer, if the load acting on the inner pins 11 is not constant, there is a risk that the load will be biased toward some inner pins. That is, it is desirable that the load acting on the inner pins 11 be distributed equally to all inner pins 11, but in reality, it may be biased to some inner pins 11 due to load fluctuations, manufacturing errors, backlash, etc. Therefore, the transmission torque cannot be increased and the entire device becomes large.

Therefore, in order to eliminate the unbalanced load applied to the inner pin 11, a planetary gear speed reducer is also known which has a structure in which an annular inner pin support ring is provided and each inner pin is inserted and held in the inner pin support ring.

However, even if this inner pin support ring is provided, the inner pin 11 is still supported in a cantilever manner, and the problem remains that the length in the axial direction becomes longer.

Furthermore, since the above-mentioned known inner pin support ring has as many insertion holes as the number of inner pins formed in the annular disc, precision is required for its manufacture, and it is difficult in terms of cost and assembly. It had become a beast.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a planetary gear reducer with an inner pin support ring for equally distributing the load acting on the inner pin, in which the inner pin is supported on both sides by the inner pin support ring. To provide a planetary gear speed reducer that reduces the axial length of the entire speed reduction mechanism, improves load stability, simplifies the manufacture of the inner pin support ring, and reduces costs. be.

(Means for Solving the Problems) The present invention is characterized by: one or more eccentric bodies provided on the input rotation shaft; an external gear fitted to the eccentric bodies; an internal gear that internally meshes with the gear; an internal pin hole formed in the external gear;
It consists of an inner pin loosely fitted into the inner pin hole, an inner pin holding flange that holds the inner pin, and an inner pin support ring made of an annular disc, and the inner pin support ring is inserted into the internal gear. In a planetary gear speed reducer in which either the internal gear or the internal pin holding flange is fixed and decelerated rotation or accelerated rotation is taken out from the other, the inner periphery of the internal pin support ring The slit portion is formed by a combination of a semicircular arc portion supporting the inner pin and a straight or curved portion.

(Example) This will be explained in detail below using figures.

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a sectional view taken along line AA in FIG.

In the following description, parts that are the same as the conventionally known configuration shown in FIGS. 3 and 4 are designated by the same reference numerals.

Since the present invention functions as both a speed increaser and a speed reducer by converting input and output, both of them are collectively referred to as a speed increase/speed reducer.

In addition, in the following description, it is demonstrated as a reduction gear.

An eccentric body 3 is provided for the input rotation 1. An external gear 5 is fitted to this eccentric body 3 via a bearing 6. This external gear 5 has external teeth 7 having a trochoidal tooth profile on its outer periphery. The internal gear 8 is an extension of the casing of the motor M and is formed integrally with the casing. Further, the internal gear 8 has an arcuate tooth profile formed of an external pin 9 provided on its inner circumferential surface and internally meshes with the external gear 5.
This outer pin 9 may have a structure in which an outer roller (not shown) is loosely fitted therein. The external gear 5 has an internal pin hole 1.
0 is formed, and an inner pin 11 is loosely fitted into the inner pin hole 10. An inner roller 12 is loosely fitted on the outer periphery of the inner pin 11.
has one end tightly fitted into the inner pin holding flange 13. Here, the inner roller 12 can be omitted. The inner pin holding flange 13 is integrally attached to the output shaft 2.

A cover 18 is fixed to the internal gear 8 on the opposite side of the casing of the motor M by bolts 19. Further, a stepped portion 20A is formed on the inner pin holding flange 13, and a bearing 21 is provided between the stepped portion 20A and a stepped portion 20B formed on the cover 18. In this way, the bearing 21
By providing the bearing 21 at the stepped portion, the bearing 21 can support both thrust load and radial load.

On the other hand, at the end of the inner pin 11 on the motor M side,
An inner pin support ring 22 made of an annular disk inscribed in the internal gear 8 is provided. A slit portion 23 for supporting the inner pin is provided in the inner circumferential surface of the center hole of the inner pin support ring 22 in the form of a groove. (or it may be a curved line). The inner pin 11 is inserted through the slit portion 23.

The retaining ring 24 is used to prevent the bearing 21 from slipping off and to receive a thrust load. Also,
The foot portion 25 provided at the bottom of the internal gear 8 is for attaching a motor and a reduction gear, but these structures are not necessarily necessary.

Furthermore, in the above explanation, the internal gear 8 is connected to the motor M.
Although the explanation has been made assuming that the inner pin holding flange 13 is rotated, it is assumed that the inner pin holding flange 13 is fixed and the internal gear 8 is rotatable separately from the casing of the motor M. , it is clear from the gist that the present invention also includes a device in which the output is taken from the internal gear 8.

Since the present invention is configured as described above, it operates as explained below.

The rotation of the motor M is applied to the eccentric body 3 through the input rotating shaft 1, and the rotation of the eccentric body 3 causes the external gear 5 to swing and rotate. Therefore, one rotation of the eccentric body 3 causes the external gear 5 to swing once, and the external gear 5 rotates by the difference in the number of teeth between the inner and outer gears.
The rotation of the inner pin 11 and the inner pin holding flange 13
is transmitted to the output side shaft 2 as a decelerated rotation.

In the above description, the case where the external gear is one is explained, but the present invention is not limited to this embodiment, and the external gear may be one or more. This is clear from the spirit of the present invention.

(Effects of the Invention) The effects of the present invention configured as described above are as follows.

Since the individual inner pins 11 are supported by the inner pin support ring 22, the transmitted torque is equally distributed to the inner pins 11 via the inner pin support ring 22, and uneven loads are prevented. Transmitted torque can be increased.

Also, since the inner pin support ring 22 is in contact with the internal gear 8, the inner pin 11 is in contact with the inner pin support ring 22.
It is supported on both sides by the bearing 21 and the bearing 21. Therefore, the rigidity of the reduction gear mechanism is improved, so that the length in the axial direction can be reduced, the structure of the output side end can be simplified, and the reduction gear can be made smaller and lighter.

In addition, the slit portion 23 of the inner pin support ring 22
Since it is in the shape of a groove that opens toward the center hole, it can be easily machined by broaching, for example, and has high precision, and at the same time can be manufactured in large quantities at low cost.

Further, since the slit portion 23 is not a circular hole but a groove formed by a combination of a semicircular arc and a straight line or curved line, it has the advantage of being easy to assemble.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, and FIG.
The drawings are a cross-sectional view taken along the line AA in FIG. 1, FIG. 3 is a cross-sectional view showing a conventionally known planetary gear reducer, and FIG. 4 is a cross-sectional view taken along the line B-B in FIG. 3. 1: Input rotating shaft 2: Output side shaft 3: Eccentric body
5: External gear 6: Roller, bearing 7: External tooth 8:
Internal gear 9: Outer pin 10: Inner pin hole 11:
Inner pin 12: Inner roller 13: Inner pin holding flange 14, 15: Cover 16: Bolt 1
7: Bearing 18: Cover 19: Bolt 20
A, 20B: Stepped portion 21: Bearing 22: Inner pin support ring 23: Slit portion 23A: Semicircular arc portion 23B: Straight portion.

Claims (1)

[Scope of Claims] 1. One or more eccentric bodies provided on the input rotating shaft, an external gear fitted to the eccentric body, an internal gear internally meshed with the external gear, Consisting of an inner pin hole formed in the external gear, an inner pin loosely fitted into the inner pin hole, an inner pin holding flange that holds the inner pin, and an inner pin support ring made of an annular disc, A planetary gear increase/decrease in which the inner pin support ring is inscribed in the internal gear, one of the internal gear or the inner pin holding flange is fixed, and decelerated rotation or accelerated rotation is taken out from the other. A planetary gear speed reducer, characterized in that a slit portion formed by a combination of a semicircular arc portion supporting the inner pin and a straight line or a curved portion is provided on the inner peripheral portion of the inner pin support ring.