JP2009197993A - Reduction gear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem, in a reduction gear of a gear mechanism by a conventional technology, that the reduction ratio thereof is determined by the tooth number ratio of mutually meshing gears, the value thereof is about 1/10 at most, and several stages of arranged gear mechanisms are required for obtaining a higher reduction ratio, thus resulting in upsizing, efficiency reduction and cost increase of the reduction gear. <P>SOLUTION: A first means of this reduction gear can provide the higher reduction ratio by transmitting only rotation torque generated in a planetary gear at its time to an output rotary shaft by a universal joint mechanism, by setting a tooth number difference in both to an extremely small value of about 1 to 3, by meshing the planetary gear with a fixed internal teeth gear. A second means also transmits only rotation torque generated in a first planetary gear mechanism to an eccentric rotary disk arranged in the middle of both via a first universal joint mechanism by arranging two planetary gear mechanisms, and further transmits only the generating rotation torque to the output rotary shaft via a second universal joint mechanism by meshing and rotating the inner periphery of the fixed internal teeth gear, by driving a second planetary gear mechanism by the eccentric rotary disk. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is arranged between a prime mover that rotates at high speed and various rotary devices that receive rotational power from the prime mover, and the rotational speed of the rotary prime mover is adjusted to a rotational speed adapted to the functions of the various rotary devices. The present invention relates to a reduction gear that performs a function of reducing and transmitting.

  Among the various rotating devices currently used in the market, rotating devices that require extremely low rotational speed, such as surveillance camera drive devices and robot devices, are widely used, and have a high deceleration rate. There is a growing demand for small reduction gears.

  As mentioned above, there is an increasing demand for compact and high speed reduction gears. However, the speed reduction mechanism of the conventional gear mechanism is at most a tenth, so that a high speed reduction rate can be obtained. Had to pile up several gear mechanisms, resulting in an increase in the size of the device, a decrease in efficiency, and an increase in price.

Means to solve the problem

In the present invention, the difference in the number of teeth between the internal gear and the planetary gear rotating inscribed therein is reduced as much as possible, and only the rotational rotational force generated by the rotation of the planetary gear is taken outside through the convolution joint mechanism. The simple mechanism makes it possible to obtain a high deceleration rate.
Furthermore, a higher deceleration rate can be obtained by connecting the speed reduction mechanism in two stages.

The invention's effect

In the reduction gear according to the present invention, the reduction rate is determined by the difference between the number of teeth of the fixed internal gear and the number of teeth of the planetary gear. By increasing the number of teeth of the gear and reducing the difference of the number of teeth, the reduction rate is extremely large. Further, by connecting the gear mechanism in two stages, the speed reduction rate becomes an astonishing value.
Moreover, the mechanism can be made much smaller and simpler than the speed reduction device of the prior art.

BEST MODE FOR CARRYING OUT THE INVENTION

Next, an embodiment of a reduction gear according to the present invention will be described with reference to the drawings.
FIG. 1 is a partially exploded perspective view showing an embodiment of a reduction gear device according to the first means of the present invention.
In the figure, reference numeral 1 denotes an input rotation axis.
An eccentric shaft indicated by reference numeral 2 and a bearing indicated by reference numeral 3 are attached to the tip of the input rotating shaft 1.
Reference numeral 4 denotes an internal gear fixed to an apparatus housing (not shown).
The center of the internal gear is the same as the center of the input rotary shaft 1.
Reference numeral 5 denotes a planetary gear.
A bearing fitting hole mounted on the eccentric shaft is provided at the center of the planetary gear 5, and the planetary gear 5 is rotatably mounted on the eccentric shaft 2.
The planetary gear 5 meshes with the fixed internal gear only at one place, and revolves only once when the eccentric shaft 2 makes one rotation.
Further, when the planetary gear 5 revolves once, the fixed gear 4 rotates by the difference in the number of teeth.
Reference numerals 6a, 6b, 6c and 6d indicate connecting pin insertion holes indicated by reference numerals 7a, 7b and 7c.
The inner diameters of the insertion holes 6a, 6b, 6c and 6d are made larger than the outer diameters of the connecting pins 7a, 7b and 7c by a dimension equal to the eccentric amount of the eccentric shaft 2.
The insertion holes 6 a, 6 b, 6 c and the connecting pins 7 a, 7 b, 7 c function as a universal joint mechanism that connects the planetary gear 5 and the output rotation shaft indicated by reference numeral 8.
Therefore, the output rotating shaft 8 rotates only by the rotation torque regardless of the revolution of the planetary gear 5.
As apparent from the above description, the reduction rate of the reduction gear is the difference in the number of teeth corresponding to the number of teeth of the planetary gear 5.
There are various types of universal joint mechanisms, but what type is adopted can be changed according to specifications required for the apparatus.
In this embodiment, the case where the number of connecting pins is four will be described, but the same operation is possible with three or five or more pins.
In this embodiment, the material of the fixed internal gear 4 and the planetary gear 5 is not particularly described. However, the metal integrated structure, the plastic integrated structure, or the metal or plastic circular ring can be used. A structure using a flexible material such as a toothed belt on the circumference or the outer circumference, or on either one of them can function in the same manner.
Furthermore, although this embodiment has been described with respect to the case where there is one planetary gear mechanism, two or three or more planetary gear mechanisms can function in the same manner.

FIG. 2 is a partially exploded perspective view showing an embodiment of a speed reduction device according to the second means of the present invention.
Reference numerals 1 to 8 are the same as those in FIG. 1, and those other than those necessary are omitted. However, since the bearing 3 is not employed in this figure, it is not drawn.
Reference numeral 9 denotes a newly added extension center axis, which has the same center as the input center axis 1 but has a smaller outer diameter. The planetary gear 4 is the same as in the case of FIG. 1, but the thickness is halved and the eccentric shaft hole is penetrated.
The connecting pin holes 6a,... And the connecting pins 7a,... Are the same as in FIG.
Reference numeral 10 denotes an eccentric disk.
The eccentric disk 10 is rotatably mounted on the central shaft 9, and is driven and rotated by a universal joint mechanism composed of the connection pin holes 6a and the connection pins 7a.
The eccentric amount of the eccentric disk 10 is the same as the eccentric amount of the eccentric shaft 2.
However, when the number of teeth of the planetary gear 5 is different from that of the second planetary gear denoted by reference numeral 11, it is necessary to set the amount of eccentricity corresponding to the number of teeth.
A shaft hole into which the eccentric disk 10 is inserted is provided at the center of the second planetary gear, and is driven by the eccentric disk 10 to rotate while meshing with the inner periphery of the fixed internal gear 4.
Reference numerals 12a, 12b, and 12c are universal joint mechanisms that transmit only the rotational rotational force generated in the second planetary gear 11 by inserting connecting pins 13a, 13b, and 13c provided on the output rotation flange indicated by reference numeral 14. Constitute.
The output rotation shaft indicated by reference numeral 8 is connected to the output rotation flange, and the rotation power is transmitted to the external rotation device as in the first embodiment.
In this reduction device, the final reduction rate is the product of the first stage configured with the planetary gear 5 as the center and the second stage reduction rate configured with the planetary gear 11 as the center.
The number of connecting pins and the material of the fixed internal gear and the planetary gear are the same as in the first embodiment.
Further, in this embodiment, the case where each of the two planetary gear mechanisms is constituted by one planetary gear has been described, but the same applies even when one or both of the two gear mechanisms are constituted by a plurality of planetary gears. It is possible to make it function.

The reduction gears of gear mechanisms currently in wide use are determined by the gear ratio of the gears meshing with each other, and the reduction rate per stage is at most a tenth, and a high reduction rate is required. Sometimes it was necessary to connect several stages, and he was hesitant to increase the size of the device, decrease the efficiency, and increase the price.
In the speed reducer according to the present invention, the speed reduction rate per stage can be increased by an order of magnitude compared with the speed reducer according to the prior art, which enables downsizing and cost reduction of the equipment and responds to the demands of the industry. Is expected to be widely used.

These are the partial exploded perspective views which show one Example of the deceleration device by the 1st means of this invention. These are the partial exploded perspective views which show one Example of the reduction gear device by the 2nd means of this invention.

Explanation of symbols

1, 2, 9, ... Input rotation axis 3, ... Eccentric shaft 4, ... ························· Fixed internal gears 5 and 11
12a, 12b, 12c,... Connecting pin insertion holes 7a, 7b, 7c.
13a, 13b, 13c, ··············································· Output shaft 10 Disc 14, ... Output rotation flange

Claims (2)

An internal gear fixed to the device, and meshing with the internal gear, rotating on the inner circumference thereof, and having a planetary gear whose number of teeth differs from the number of teeth of the internal gear by at least one or more,
It rotates at the center position of the fixed internal gear, and includes an input rotation shaft that drives the planetary gear by an eccentric shaft provided at the tip thereof.
Furthermore, a universal joint mechanism is provided on the side surface of the planetary gear,
A speed reducer, wherein only the rotational rotational force generated in the planetary gear is transmitted from the universal joint mechanism to an output rotary shaft connected to the other end. An internal gear fixed to the device and two planetary gears that mesh with the internal gear and rotate on the inner periphery thereof, and whose number of teeth differs from the number of teeth of the internal gear by at least one or more. Prepared,
An eccentric rotating disk that rotates at the center position of the fixed internal gear, drives the first planetary gear with an eccentric shaft provided at the tip thereof, and further drives the second planetary gear at the tip of the eccentric shaft. It has an input rotation axis with an extended central axis that supports
The eccentric rotating disk is connected to the first planetary gear by a first universal joint mechanism, and only its rotational rotational force is transmitted,
The eccentric rotating disk is rotatably fitted in a shaft hole provided in the center of the second planetary gear, drives it, and engages and rotates the inner periphery of the fixed internal gear,
In addition, the second universal joint mechanism that connects the second planetary gear and the output rotating shaft transmits only the rotational rotational force generated in the second planetary gear to the output rotating shaft. .

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