WO2008114851A1

WO2008114851A1 - Precession type gear speed reducer

Info

Publication number: WO2008114851A1
Application number: PCT/JP2008/055190
Authority: WO
Inventors: Atushi Ota
Original assignee: Atushi Ota
Priority date: 2007-03-15
Filing date: 2008-03-14
Publication date: 2008-09-25
Also published as: JP2008256199A

Abstract

Provided is an inexpensive speed reducer, which has low vibrations, a high efficiency and a simple constitution. External gears are arranged on the outer circumferences of the two bottom faces of an inner part (3), and internal gears are arranged on the inner circumferences of an outer part at positions where they mesh in a radial direction at two confronting faces when the inner part (3) deviates circumferentially of the axis of a precession. The external gears and the internal gears are made given different tooth numbers, so that they slightly rotate backward by the difference to the input of one precession rotation. When an input (1) is considered to act as the speed reducer and an outer part is made in a fixed state, this speed reducer has a rocking motion generating device for rocking (5) the axial end (4) for causing the precession of the inner part (3). When the output is considered to act as the speed reducer, an output (7) is followed, when it is a slight reverse rotation of the inner part, by a high-speed precession. In order to extract the rotations exclusively, therefore, the output shaft is equipped with the internal gear by boring the inside of the inner part and equipped with the external gear for meshing with the inner gear.

Description

Ming Thin Precession Gear Reducer

Technical field

The present invention relates to a speed reduction mechanism for a reduction gear. Background art

Conventionally, there is a reduction gear that precesses one of two bevel gears with different number of teeth.

However, it seems that the vibration is large due to the movement close to the swing and the weight balance. In addition, it is thought that the force escapes because a thrust load is applied. In addition, the contact angle is shallow and there are many contact surfaces, so tooth interference is large. In addition, structurally, it is necessary to prevent the rotation of the oscillating body, but it was difficult (Patent Publication 7-2 4 8 4 7).

Even in a general trochoic speed reducer, it seems that the weight balance is bad because the gear swings.

In the wave gear reducer, there is no oscillation and little vibration, but because the ellipse is rotated, it seems that the resistance is high and the efficiency is low even when there is no load. In addition, high accuracy is required and the cost is high.

Therefore, a reduction gear that can rotate in a well-balanced manner, is efficient, and can be supplied at low cost is required. Disclosure of the invention

It is said that the rotation transmission by the gear meshing is efficient. In addition, the rotational torque transmission capacity is higher in the radial direction than in the thrust direction. Next, when you flip the coin with your finger on the desk, the precession movement continues for a while at the end and stops. It is a stable and well-balanced exercise other than ¾, which is shaken in a complex manner. Therefore, we will find a solution to teeth that combine the above three elements, that is, precession and have teeth in the radial direction. A basic speed reduction mechanism of the speed reducer of the present invention will be described. 5th ^^ 只丄 4 and f, or “Me”, consists of two parts: inner part and outer part. The inner part includes at least one external gear at any location on the outer periphery of the substantially circular cylinder. The substantially cylindrical and external gear are firmly fixed. The outer part is provided with at least one internal gear at any location inside the hollow substantially cylinder. The hollow substantially cylinder and the internal gear are firmly fixed. This is a positional relationship in which part or all of the inner part is built in the outer part. Either the inner part or the outer part precesses. At that time, the inner part and the outer part are in radial contact with each other at least at one point. The external gear of the inner part and the internal gear of the outer part are provided at the contact position. The external gear and the internal gear have a difference in the number of teeth. Depending on the difference in the number of teeth, or the difference in diameter, or both the difference in the number of teeth and the difference in diameter, the rotation of the precession rotation is slightly rotated or reversed by the difference element. The above is the minimum component of the speed reduction mechanism of the present invention.

Considering the input (1) to act as a speed reducer, if the outer part (2) is fixed, it is necessary to precess the inner part (3) (Fig. 4). Therefore, the shaft end (4) of the inner part must be swung (5). In other words, a separate swing generator is required. There are various conceivable structures for the rocking generator, but there is a method of converting rotation to rocking with an eccentric bearing (6).

Also, when considering the output to act as a speed reducer, if a slight forward or reverse rotation of the inner part becomes output (7), the output will be accompanied by a high-speed precession. In order to extract only the rotation, it is conceivable to pass the pin through the inner part like a general oscillating speed reducer. Or, the inside of the inner part is cut out. (8) An internal gear (9) is provided, and an output shaft (1 1) having an external gear (10) meshing with the internal gear is installed. It is also possible to do.

Now, assuming that the feature of claim 1 is provided, in other words, as a speed reduction mechanism having a structure satisfying the condition of claim 1, there are roughly two positions where the external gears are installed. That is, first, the inner part is provided with a single external gear at any location on the outer periphery of the substantially circular cylinder. Either the inner part or the outer part precesses. At that time, if there is only one internal gear arranged on the outer part, the external gear on the inner part and the internal gear on the outer part mesh in the radial direction at only one location. However, the way to meet is When the inner part performs precession, the axis of the precession moves to ^ 鬥 u PI ^ DO ^ m iHj, and when it shakes, the inner gear meshes with the outer gear. When the inner part shakes in the axial direction when viewed from the axis of motion, it may mesh with the internal gear of the outer part (1 2).

In the speed reduction mechanism according to claim 2, the two speed reduction mechanisms according to claim 1 are used for the purpose of stagnation at two or more locations. As described above, there are two types of conflicting methods, which are described below. When the external gear (1 3) is firmly fixed to the outer periphery of both bottom surfaces of the inner part (3) and the inner part is shaken in the circumferential direction when viewed from the axis of the precession, the two parts (1 4 The internal gear is placed inside the outer part at the position where it squeezes in the radial direction. At this time, the force acts so that the two external gears of the inner part push the inner side of the outer part (1 5), so the allowable torque increases. The following is another approach. When the inner part is shaken in the axial direction as seen from the axis of the precession, the internal gear is placed inside the outer part at a position where the two parts face each other in the radial direction (Fig. 1). Four )

The speed reduction mechanism according to claim 3 will be described below. The external gear is firmly fixed to the outer circumferences of both bottom surfaces of the inner part according to claim 2, and the inner teeth on the inner side of the outer part are in positions where the two parts face each other as seen from the axis of the precession. Although it is an element included in the speed reduction mechanism with gears, it has a special description that has features to further increase performance. One or both of the heel-side part and the outside part are characterized by the gears facing in the axial direction when viewed from the axis of the precession, and the number of teeth is the same and the position of the mountain is shifted. . Two general examples are given below. The first is described below. In the inner part of the speed reducer according to claim 2, the teeth facing in the axial direction when viewed from the axis of the precession are the same in number of teeth, and the position of the mountain (16) is shifted by a half pitch (17) It is what. The two external gears arranged on the outer periphery of the bottom surface of the inner part of the reducer mesh with the two internal gears of the corresponding outer part, but the shape and length of the inner part or the outer part Depending on the diameter and other conditions, there may be a case where only one internal gear of the outer part is required (18). In that case, if the two external gears of the inner part are bilaterally symmetric, the reduction gear has two teeth. However, if the two external gears of the inner part have the same number of teeth and are shifted by a half pitch, a reduction gear with one tooth difference is established. The second specific below An example is given. In both the inner part and the outer part, the teeth facing the precession OSS ^ 卿卿ソソ兄 sword, the number of teeth is the same, and the peak position is shifted by a quarter pitch It is what. Specifically, regarding the speed reducer according to claim 2, when a pair of external gears meshing with one external gear of the inner part is used as a pair, the relationship with the other external gear. However, it can be said that it is out of phase by about a quarter pitch. If the position of the mountain is not misaligned, look at the two opposing claws as seen from the precession axis, and when one of the claws is deepest, the other Even in the meeting section, they rub deeply. The rotation is a little more advanced, and when it is the shallowest part of the mating part, it is the shallowest part of the other part. In other words, the axis angle of the precession increases or decreases. It becomes a factor of vibration and backlash. By securing a phase difference of about a quarter of a pitch, when one side squeezes deepest, the other squeezed part can squeeze the shallowest, reducing vibration and backlash. . The reason why the pitch is set to about a quarter pitch is that there is a slight deviation due to the shape of the teeth.

The speed reduction mechanism according to claim 4 will be described below. A plurality of inner parts and outer parts of the speed reduction mechanism according to claim 1 are used and connected on the shaft center to improve the performance. An inner part with an external gear group in which a plurality of external gears are rotatably connected by a bearing or the like, and an outer part with an internal gear group in which a plurality of internal gears are firmly fixed on an axis Consists of. Alternatively, an inner part having an external gear group in which a plurality of external gears are firmly fixed on the shaft center and a plurality of internal gears on the shaft core are connected by a bearing (19) or the like so as to be rotatable. It is comprised by the outer part provided with the internal gear group. In each group, there are gears with misaligned tooth peaks or gears with different Z and tooth pitches. In each group, there are gears with misaligned tooth crests or gears with different Z and tooth pitches (Fig. 9, Fig. 10, Fig. 11, Fig. 12). As a result, one (2 0) of the connected outer parts can be output. Moreover, a large reduction ratio can be obtained by these.

The speed reduction mechanism or the rotation transmission mechanism according to claim 5 will be described below. Hollow substantially cylinder-Consists of an outer part with internal teeth inside and an inner part with external teeth on the outer circumference of a roughly circular cylinder In the state where the axis of the outer part and the inner part is tilted, it is the positional relationship (Fig. 13). It is characterized in that the teeth crawl at two points facing each other as seen from the intersection. It does not perform precession but rotates in a tilted state.

The speed reducer, speed increaser or rotation transmission mechanism according to claim 6 will be described below. In the reduction gear, the speed increaser or the rotation transmission mechanism according to claims 1 to 5, the inner part is provided with an external gear, and the outer part is provided with an internal gear. However, the present invention is not limited only to the meshing of gears. For example, instead of the tooth of the gear, a structure with a roller bearing at the tip of the tooth, or a structure in which a bearing is arranged at the valley of the tooth and the ball moves along the valley, or without the tooth A structure that transmits force by friction can be considered.

The speed reduction mechanism according to claim 7 will be described below. In the speed reducer or the speed increaser according to claim 2, the external gear is firmly fixed to the outer periphery of both bottom surfaces of the inner part, and is located at a position where the two parts face each other as seen from the axis of the precession motion. The internal gear is arranged inside the outer part. The speed reduction mechanism, that is, the wave generator according to claim 7 has a structure in which a fleta spline is inserted between the outer part and the inner part in the speed reduction mechanism according to claim 2. In addition, the above-mentioned inner part gear teeth can be eliminated, that is, a substantially cylindrical structure is also conceivable. In either case, an oscillation generator is required separately. Brief Description of Drawings

Figure 1 is a side view of an inner part with external gears on both bottom surfaces of the cylinder.

Fig. 2 is a cross-sectional view of an outer part with an external gear inside the cylinder.

Fig. 3 is a cross-sectional view showing how the inner part is built into the outer part, and the teeth are facing each other as seen from the shaft core.

Fig. 4 is a simplified cross-sectional view showing that the inner part is built into the outer part, the teeth are facing each other as seen from the shaft center, and the inner part is precessing.

Fig. 5 is a simplified diagram showing that the position of the crests of the gears facing in the axial direction when viewed from the axis of the precession is shifted by a half pitch in the inner part. FIG. 6 is a simplified perspective view showing that the position of the axis ijw _¾ is shifted by a half pitch as viewed from the axis of the precession in the inner part.

Fig. 7 is a cross-sectional view showing an embodiment of a precession speed reducer in which an inner part is cut out and an output shaft is installed.

FIG. 8 is a cross-sectional view showing an embodiment of a precession speed reducer in which an output shaft is installed by hollowing out the inside part.

Fig. 9 shows an example of a precession speed reducer characterized in that, in the pair of external gears facing the axial direction of the inner part, the pitches of the teeth facing in the axial direction are different as seen from the axis of the precession movement. FIG.

Fig. 10 shows an example of a precession speed reducer characterized in that in the pair of external gears facing the axial direction of the inner part, the pitches of the teeth facing in the axial direction are different as seen from the axis of the precession movement. FIG.

FIG. 11 is a simplified diagram showing an embodiment of a precession speed reducer in which a pair of external gears opposed to each other in the axial direction of the inner part straddles an outer part connected via a bearing. Fig. 1 2 shows the external gear of the inner part, with the pitch of teeth facing each other in the axial direction differing from the axis of the precession movement, and straddling the outer part connected via the bearing. Sectional drawing which shows the Example of the precession motion reducer.

Fig. 13 is a cross-sectional view showing a rotation transmission mechanism having an angle conversion function.

Fig. 14 is a cross-sectional view showing an external part with internal parts built in and the teeth facing each other as seen from the shaft core. BEST MODE FOR CARRYING OUT THE INVENTION

According to claim 1, it consists of at least two parts, an inner part and an outer part. The inner part is provided with at least one external gear at any location on the outer periphery of the substantially circular cylinder. The substantially cylinder and the external gear are firmly fixed. The outer part is provided with at least one internal gear at some location inside a hollow, substantially cylindrical shape. The hollow approximately cylinder and the internal gear are firmly fixed. Either the inner part or the outer part precesses. At that time, the inner part and the outer part are in contact with each other only in the radial direction. The external gear of the inner part and the internal gear of the outer part are provided at the contact position. External gear and internal tooth Cars have a difference in the number of teeth. The difference between the number of teeth or the difference between the diameter, people f I _¾ Chicks; by "/ source E this responsibility" Bruno Bruno both elements, minute only slightly forward of the elements of the difference with respect to the input of the precession one rotation If the number of teeth of the internal gear is larger than that of the external gear, the rotation is reversed with respect to the input, and if the number of teeth of the internal gear is smaller than that of the external gear, the rotation is normal with respect to the input. For example, even if the number of teeth of the external gear is extremely small, if the pitch and diameter are large, several teeth of the internal gear are skipped and the next tooth is mixed. Because it fits.

Also, when considering the output to act as a speed reducer, if a slight forward or reverse rotation of the inner part becomes output (7), the output will be accompanied by high-speed precession. In order to extract only the rotation, it is conceivable to pass the pin through the inner part like a general reduction gear. In addition, the inside of the inner part is cut out (8) The internal gear (9) is installed, and the output shaft (1 1) is installed with the external gear (10) meshing with the gear It is also possible to do this.

Now, as a speed reduction mechanism having a structure that satisfies the condition described in claim 1, there are two installation positions of the internal gear of the outer part. First, the inner part is provided with one external gear on either one of the bottom surfaces of the substantially cylindrical shape. And the inner part precesses. At that time, if there is only one internal gear arranged on the outer part, the external gear on the inner part and the internal gear on the outer part mesh in the radial direction at only one location. However, there is another way to squeeze, when the inner part sways in the circumferential direction as seen from the axis of the precession movement, and when it squeezes in the radial direction with the internal gear of the outer part. When the inner part shakes in the axial direction as seen from the axis of motion, it may mesh with the toothed gear of the outer part in the radial direction (1 2).

In the speed reduction mechanism according to claim 2, the two speed reduction mechanisms according to claim 1 are used for the purpose of stagnation at two or more locations. As above, there are roughly two The first one is the bottom of the inner part (3). IMJ _{7N 7 ¾} Difficult

3) When firmly fixed, and when the inner part shakes in the circumferential direction when viewed from the axis of the precession, the inner part of the outer part is in a position where the two parts (14) face each other in the radial direction. A toothed wheel is arranged. At this time, the force acts so that the two external gears of the inner part push the inner side of the outer part (15), so that the allowable torque increases. Secondly, when the inner part is shaken in the axial direction as seen from the axis of the precession, the outer part is in a position where the two parts face each other (Fig. 14). The internal gears are arranged inside.

In the speed reduction mechanism according to claim 3, the external gear is firmly fixed to the outer periphery of both bottom surfaces of the inner part, and the outer portion is located at a position where the two parts face each other when viewed from the axis of the precession motion. Although the reduction gear mechanism has internal gears on the inside of the product, the gears facing in the axial direction when viewed from the axis of the precession motion are the same in one or both of the inner and outer parts. The feature is that the position of the mountain is shifted. Two general examples are given below. The first is described below. In the speed reduction mechanism where external gears are firmly fixed to the outer periphery of both bottom surfaces of the inner part, and the internal gears are arranged on the inner side of the outer part at a position where the two parts face each other as seen from the axis of precession. The teeth facing in the axial direction as seen from the axis of the precession of the inner part have the same number of teeth and the peak position (16) is shifted by a half pitch (17). The two external gears arranged on the outer periphery of the bottom surface of the inner part of the speed reducer mesh with the two internal gears of the corresponding outer part, but the shape and length of the inner part or the outer side Depending on the conditions such as the diameter of the part, there may be a case where only one internal gear (18) is required for the two external gears of the outer part. In that case, if the two external gears of the inner part are bilaterally symmetric, the reduction gear has two teeth. However, if the two external gears of the inner part have the same number of teeth and a half-pitch shift, a speed reducer with one tooth difference is established. This is because even if there is a difference in the number of teeth, it can be seen from the other side. Next, the second is described below. In both the inner part and the outer part, the teeth facing in the axial direction as seen from the axis of the precession movement are characterized by the same number of teeth and the position of the crest shifted by a quarter pitch. Is. Specifically, regarding the speed reducer according to claim 2, when the internal gear of the outer part that meshes with one external gear of the inner part is a pair of meshes, the other gear It can be said that the relationship is out of phase by about a quarter pitch. If the mountain is not misaligned, Looking at the two opposing claws as seen from the precession axis, it is the deepest in the other mating part when it is mated deepest in the sword ¾ | part. They are meeting each other. A little more than 0 turns, and when it is the shallowest part of the mating part, it is the shallowest part of the other part. In other words, the axis angle of precession is increasing or decreasing. It becomes a factor of vibration and backlash. By securing a phase difference of about a quarter of a pitch, when one side is deepest, it is possible to squeeze the shallowest at the other side, reducing vibration and backlash. The reason why the pitch is set to about a quarter pitch is that there is a slight deviation due to the shape of the teeth.

The speed reduction mechanism according to claim 4 has a structure in which a plurality of inner parts and outer parts of the speed reduction mechanism according to claim 1 are used and connected on the shaft center to improve performance. It is an inner part with an external gear group in which multiple external gears are rotatably connected by means of bearings, etc., and an outer part with an internal gear group in which multiple internal gears are firmly fixed on the axis. Configured. Alternatively, an inner part with an external gear group firmly fixed to a plurality of external gears on the shaft center and a plurality of internal gears on the shaft core can be rotatably connected by a bearing (19). It consists of outer parts with internal gear groups. In each group, there are gears with misaligned tooth peaks or Z and gears with different tooth pitches (Fig. 9, Fig. 10, Fig. 11, and Fig. 12). One of the connected outer parts can be used as an output (Fig. 9, Fig. 10, Fig. 11, Fig. 12). A simple structure can be considered by straddling the external gear of the inner part over the connecting part (Figs. 11 and 12). In addition, a large reduction ratio can be obtained as follows. In other words, when the internal gear of the inner part has two stages, the number of teeth of the internal gear (2 2) of the outer part (2 1) on the input side is set to 30 and the inner side of the inner part that fits the outer gear (2 1) The number of teeth of the toothed gear (2 3) and the other external gear (2 4) is 29, and the number of teeth of the internal gear (2 5) of the output side outer part (2 0) is 28. Assuming that the number of teeth of the external gear (2 6) and the other external gear (2 7) of the inner part that fits each other is 29, the inner part that has already been decelerated and reversely rotated with respect to the input Is further decelerated because it rotates slightly forward (Fig. 12).

The speed reducer, speed increaser or rotation transmission mechanism according to claim 5 will be described below. Hollow The outer part with inner teeth inside the cylinder and the outer circumference of the cylinder ¾ τ;

(Fig. 1 3) shows the positional relationship (20) where the inner part slightly enters the outer part. At this time, it is characterized in that the teeth squeeze in two places facing each other when viewed from the intersection of the axes. Is. That is, in the speed reducer or speed increaser according to claim 2, the precession is performed with either the inner part or the outer part tilted, but in this speed reducer or speed increaser or rotation transmission mechanism, The place where the speed reducer or speed increaser according to claim 2 is engaged is the same, but it does not perform precession and rotates in an inclined state. Therefore, it can be determined by the presence or absence of a rocking generator, but it cannot be distinguished when viewed from the stand-alone mechanism and in a stationary state. It does not matter which is the input side and which is the output side. If there is a difference in the number of teeth between the internal gear and the external gear, the rotation transmission mechanism can be slightly reduced or increased. If the number of teeth is the same, the rotation transmission mechanism has an angle conversion function. Note that the conversion angle depends on the difference in diameter between the inner part and the outer part at the mating part.

The speed reducer, speed increaser or rotation transmission mechanism according to claim 6 will be described below. In the reduction gear, the speed increaser or the rotation transmission mechanism according to claims 1 to 5, the inner part is provided with an external gear, and the outer part is provided with an internal gear. However, the present invention is not limited only to the meshing of gears. For example, instead of the gear teeth, a structure having a roller bearing at the tip of the teeth is conceivable. Alternatively, a structure in which bearings are arranged in the valleys of the teeth and the balls move along the valleys can be considered. Or, it may have a structure that eliminates teeth and transmits force by friction. For friction, the reduction ratio depends on the difference in diameter between the inner and outer parts. In addition, if both the inner part and the outer part are made into a truncated cone, a continuously variable transmission mechanism is obtained.

The speed reduction mechanism according to claim 7 will be described below. In the speed reduction mechanism, that is, the wave generator according to claim 7, only the inner part of the speed reduction mechanism according to claim 2 is used, so that only the inner part has the structure (3), that is, both bottom surfaces of the substantially cylindrical shape. It is the structure provided with the external gear on the outer periphery of. Another part to function as a wave gear reducer is an outer part (2), in other words, a circular spline for a wave gear reducer. This is the positional relationship in which the inner parts that perform the precession are placed inside the Sakiyura Spline. Its inner parts precess, flex Sakiyura's spline that fits with the spline, j ifln, // e e is connected, Sakiyura 'the spline and the teeth mate, the two external gears of the inner part are the fleta spline A force acts to push and spread the inside of the circular spline (15). In other places, the diameter becomes shorter and the teeth are separated, making it useful as a wave generator. Therefore, the fret spline of the conventional wave gear reducer has wavy teeth only on the outer side, but the furer spline of the present invention also has teeth that mesh with the gear that performs precession. .

Or, in a speed reduction mechanism with a precession of a substantially cylindrical inner part that does not have an external gear, there are no teeth inside the freta spline.

In the case of this speed reduction mechanism, a swing generator is also required separately.

The following are general points to keep in mind when implementing the present invention. Since the meshing portion of the external gear and the internal gear according to the present invention has a positional relationship in which the external gear obliquely contacts the internal gear, both have the same shape in order to ensure the meshing. It is desirable that the result tooth has a substantially triangular frustum shape. As a result, in terms of inner parts, a shape with the corners of the bottom of the cylinder almost dropped is desirable. In addition, if both teeth are formed in a helical helical gear shape, it is thought that the stagnation rate will increase.

In the inner part, the outer part, or the outer part that is connected via a bearing and divided, in other words, where the fixed side can be changed according to the purpose, the input side can also be changed and increased. It can also be a speed machine. Various combinations are possible for differences in the number of teeth. Industrial applicability

There is little vibration. Since a radial load can be applied, a large torque is applied. Efficiency is good. The structure is simple and has little influence on machining accuracy, and is inexpensive.

Claims

Range of requests

1. Consists of an inner part with an external gear at some location on the outer circumference of a cylinder and an outer part with an internal gear at some location on the inner circumference of a hollow cylinder. In this case, a part of the positional relationship is built in the outer part, and the inner part and the outer part perform precession relative to each other in a state where the external gear of the inner part and the internal gear of the outer part are in mesh. A speed reducer or speed increaser characterized by that.

2. A position relationship consisting of an inner part with external gears on the outer circumference of both bottom surfaces of a substantially circular cylinder and an outer part with internal gears on the inner circumference of a hollow cylinder. The inner part is built into the outer part. The inner part and the outer part perform precession relative to each other, and the external gear of the inner part and the internal gear of the outer part are in two positions facing each other when viewed from the axis of the precession. A speed reducer or speed increaser characterized by

3. In one or both of the inner part and the outer part of the reduction gear or the speed increaser according to claim 2, the gears facing in the axial direction when viewed from the axis of the precession have the same number of teeth. The mountain is misaligned.

4. An inner part having an external gear group in which a plurality of external gears are rotatably connected on the shaft center by means of bearings, and an internal gear group in which a plurality of internal gears are connected and fixed on the shaft center. Consists of outer parts with

Alternatively, an inner part having an external gear group in which a plurality of external gears are connected and fixed on the shaft core, and an internal gear group in which a plurality of internal gears are rotatably connected to the shaft center by means of a bearing or the like. Consisting of outer parts with

Gears with misaligned teeth and / or gears with different tooth pitch are mixed in each group of inner and outer parts in the above two ways, and the inner parts are built into the outer parts. The inner part and the outer part perform precession relative to each other, and the external gear group of the inner part and the inner part of the outer part in two directions facing each other as seen from the axis of the precession. A reduction gear or a speed increase gear characterized in that a group of toothed gears mesh.

5. Consists of an outer part with internal teeth inside a hollow, generally cylindrical cylinder, and an inner part with outer teeth on the outer periphery of a substantially circular cylinder, with the outer part and the inner part tilting the axis. This is the positional relationship in which the inner part slightly enters the part. Reducer or i ¾bT », characterized in that the teeth meet at two points on the surface.

6. In the speed reducer or step-up gear or rotation transmission mechanism according to claims 1 to 5, a roller bearing is provided at the tip of the tooth instead of the tooth of the external gear or / and the internal gear. It has a structure, or a structure in which a balling moves in the valley of the tooth and the ball moves along the valley, or a structure that transmits the force by friction without the teeth.

7. A structure with external gears on the outer periphery of both bottom surfaces of a substantially circular cylinder, where the above-mentioned substantially circular cylinder performs precession, making it useful as a wave generator for a wave gear reducer, It is used as a wave generator for wave gear reducers by performing differential motion.