JPH0330741B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is utilized in the technical field of gear devices, and particularly relates to a planetary differential gear device using non-circular gears.

(Prior art) In factory equipment, office equipment, etc., for example, the rotation of the output shaft of a general-purpose 4-pole motor is decelerated by a deceleration means, and this decelerated constant speed rotation is then converted into oscillation, oscillating rotation, intermittent rotation, etc. It is often necessary to achieve non-uniform speed rotation, and it has been widely practiced in the past to use non-uniform speed means such as a cam mechanism or a Geneva mechanism. However, this requires both a deceleration means and an inconstant speed means, which not only increases the installation area but also makes the device expensive. Furthermore, conventional cam mechanisms and Geneva mechanisms have the drawbacks of being limited in the inconstant speed rotation that can be achieved, having a high slip rate, and having poor mechanical efficiency.

On the other hand, planetary differential gears have been widely used as compact devices that can provide high reduction ratios. On the other hand, circular gears (gears with a circular pitch line shape) have traditionally been most commonly used, and although non-circular gears have never been considered, conventional gears such as elliptical gears have It was limited to what could be processed. Therefore, even if a planetary differential gear device is manufactured by combining elliptical gears, the change in angular velocity of the unequal angular velocity output relative to the constant angular velocity input can only be achieved within a limited range.

In addition, with the recent development of computers, it has become practical to design and process non-circular gears other than elliptical gears (Proceedings of the 1981 Kansai Regional Academic Conference of Japan Society of Precision Machinery 109) (See pages 38 onwards, and the collection of papers from the 2nd Design Automation Engineering Conference, page 38 onwards). However, using only one set of such non-circular gears does not provide the intermittent rotation, oscillation, and oscillating rotation required for automation of various devices, so it is difficult to incorporate them into the planetary differential gear system described above. As a result, the above-mentioned non-uniform rotational motion useful for automation was obtained, and an attempt was also made to integrate the deceleration means and the non-uniform velocity means (Proceedings of the Japan Society of Mechanical Engineers (Part 3)) 39 (See Vol. 317, p. 393 et seq.) In other words, the conventional planetary differential gear system based on this attempt, as schematically shown in FIG. A planetary gear d is rotatably supported on the planetary shaft c, and the planetary gear d is integrally formed with a driving side gear e and a driven side gear f, and the driving side gear e is connected to a fixed gear g and a driven side gear. The side gear f meshes with the output gear h, and the output gear h is integrally provided with an output shaft j that is pivotally supported by the case.
These gears are non-circular gears. The planetary differential gear device constructed in this way can be evaluated as one that integrates a reduction means and an inconstant speed means, but on the other hand, while the input shaft a rotates at a constant speed, the output shaft rotates at a constant speed. Since j rotates at an inconstant speed, acceleration acts on each component on the output side, and the transmission force or load acting between the components on the input side and the output side pulsates. For this reason, it is necessary to increase the strength of each part compared to a conventional planetary differential gear device using circular gears. In particular, the planetary shaft c or the planetary gear d
Since only one is provided eccentrically with respect to the input shaft a, the center of gravity of the part that rotates with the input shaft a is also eccentric, making it impossible to maintain gravity balance, and the force acting on the tooth surface of the planetary gear d is also eccentric to the carrier. b acts eccentrically on the input shaft a, so a large bending moment acts on the input shaft a, and this input shaft a
The dimension from to planetary shaft c becomes larger, and the bearing that supports input shaft a also becomes larger, and for the same reason, a bending moment also acts on output shaft j,
However, the gear system as a whole had the disadvantage of being large and heavy, and it was necessary to eliminate these disadvantages in order to put it into practical use.

(Problems to be Solved by the Invention) In the present invention, in a planetary differential gear device using non-circular gears as described above, a large stress is applied especially to the input shaft, and the whole becomes large and heavy. This is an attempt to solve the problem of becoming.

(Means for Solving the Problems) Means for solving the above problems will be explained with reference mainly to FIG. 1, which shows the basic main parts of the present invention.

The planetary differential gear device 1 of the present invention has one end 5a connected to the input shaft 2 by a carrier 4 fixed to the input shaft 2 (for example, rotatably supported by a casing 3). A planetary shaft 5 is provided eccentrically (separated in parallel, for example) with respect to the planetary shaft 5, and a planetary gear 6 is rotatably supported on this planetary shaft 5. The planetary gear 6 includes a driving side gear 7 and a driven side gear 8
are integrally formed. And the driving side gear 7
The fixed gear 9 (for example, fixed integrally with the casing 3) and the driven gear 8 are arranged to mesh with the output gear 10, respectively. The output gear 10 is integrally provided with an output shaft 11 (for example, rotatably supported by the casing 3).

The driving gear 7 and the fixed gear 9 and/or the driven gear 8 and the output gear 10 are formed into non-circular shapes whose pitch lines are rotationally symmetrical. The planetary shafts 5 are provided at symmetrical positions with respect to the input shaft 2 by the number of symmetrical numbers (for example, 2 when the pitch line of the fixed gear 9 is 9c as shown in FIG. 2), and therefore the planetary gears 6 are also arranged symmetrically. This is provided on each planetary shaft 5.

(Function) Next, the function of the above means will be explained. An input shaft 2 connected to an output shaft of a power means such as a motor rotates at a constant speed in the direction shown by the arrow in the figure. Accordingly, the planetary shaft 5 integral with the input shaft 2 also revolves around the input shaft 2 at the same speed, and each planetary gear 6 also revolves at a constant speed. At the same time, due to this revolution, each driving side gear 7 engages with the fixed gear 9 and rotates in the direction shown by the arrow in the figure. At this time, if each driving side gear 7 and fixed gear 9 are a pair of non-circular gears as shown in FIG. has an inconstant velocity. On the other hand, if the driven gear 8 and the output gear 10 are circular gears, the above-mentioned non-uniform rotation of each driven gear 8 is decelerated relative to the constant rotation of the input shaft 2, and the output gear 10 is The signal is transmitted to the output shaft 11 via the signal.

In this case, the rotation angle Θ of input shaft 2 and output shaft 1
As shown in FIG. 3, one cycle of change in the rotation angle Φ ends when the rotation angle Θ reaches Θ ₂ . And now if we set i=2π/Θ ₂ ,
When i≧2 and i is a natural number, the rotation angle Φ changes in i cycles between zero and 2π, and in this case, i planetary gears 6 can be provided symmetrically.

(Embodiment) A first embodiment of the present invention will be described below with reference mainly to FIG. 4.

The casing 3 includes a yoke 3a and a front lid 3b fitted in front and behind the yoke 3a to prevent oil leakage.
and a rear lid 3c.

The input shaft 2 passes through the front cover 3b and is supported by a ball bearing 13, and is further supported by an oil seal 1.
4 is fitted to prevent oil leakage at the penetration point.

In this embodiment, the carrier 4 is formed as a disk integrated with the input shaft 2, and an output shaft 11 concentric with the input shaft 2 extends between the center portion and the rear cover 3c.
is rotatably supported by roller bearings 15 and ball bearings 13. Further, an oil seal 14 is also fitted at a portion where the output shaft 11 passes through the rear cover 3c.

A fixed gear 9 is fixedly installed inside the case 3 of the rear lid 3c so as to be coaxial with the output shaft 11, and a hole 9a through which the output shaft 11 passes is bored in the center of the fixed gear 9.

A cylindrical portion 9b is formed on a part of the outer periphery of the fixed gear 9, and a disc-shaped rotating body 12 is rotatably supported by a ball bearing 13 on this cylindrical portion 9b.

One end side 5a and the other end side 5b of the two planetary shafts 5 are connected and fixed by nuts 5d between the carrier 4 and the rotating body 12, so that the planetary shafts 5 are supported symmetrically.

A planetary gear 6 is rotatably supported on these planetary shafts 5 by a roller bearing 15, and a driving side gear 7 and a fixed gear 9 of the planetary gear 6 are arranged along a pitch line as shown in FIG. 2, for example. 7a and 9c
The gears are formed as non-circular gears and are meshed with each other.

On the other hand, an output gear 10 is fixed to the output shaft 11, and is formed as a circular gear and meshes with the driven gear 8 of each planetary gear 6.

Drive side gear 7 and fixed gear 9 in this embodiment
The rotationally symmetrical pitch line of a non-circular gear with
As mentioned above, the pitch line 7a of the driving side gear 7 and the pitch line 9c of the stationary gear 9 are shown in FIG. 2 as an example. Input shaft 2 when using main drive side gear 7 and fixed gear 9 that have pitch lines of this shape
The rotation angle Φ of the output shaft 11 corresponding to the rotation angle Θ of
As shown in Fig. 3, the rotation angle Φ reaches Φ ₁ at the rotation angle Θ ₁ , and then the rotation angle Θ ₂
The rotation angle Φ maintains Φ ₁ until . That is, in this case, the output shaft 11 rotates intermittently and can be used for indexing in automatic machines and the like.

In addition, as the main drive side gear 7 and the fixed gear 9 are non-circular gears, within the range of the above-mentioned conditions that i≧2 and i is a natural number, the form of one cycle of change in the rotation angle Φ may be oscillation or It is also possible to use a non-circular gear having a pitch line shape that performs oscillating rotation.

Also, the pitch line 7 between the driving side gear 7 and the fixed gear 9
If the shapes of b and 9d are made as shown in FIG. 5, i=3 in this case, and three planetary shafts 5, that is, three planetary gears 6 can be provided symmetrically with respect to the input shaft 2.

In the above embodiment, the driving side gear 7 and the fixed gear 9
A non-circular gear is used in combination with the driven gear 8.
Although the combination of the output gear 10 and the output gear 10 is a circular gear, the combination of the gears 7 and 9 may be a circular gear, and the combination of the gears 8 and 10 may be a non-circular gear. Furthermore, both combinations may be non-circular gears.

Next, a second embodiment of the present invention will be described with reference to FIG. However, the same means as those explained in the first embodiment are given the same reference numerals, and differences from the first embodiment will be mainly described.

In this embodiment, the input shaft 2 has a cylindrical shape with a hollow hole 2a bored in its center, and the output shaft 11 passes through this and is supported by a roller bearing 15. Both shafts 2 and 11 protrude from the 3b side. In this embodiment, with the above configuration, the load on the output side is changed from driven gear 8 to output gear 10 to output shaft 1.
1, the shaft length of the part where the torque acts due to the configuration that supports the output shaft 11 can be shortened.
This is advantageous in terms of strength and is convenient when both the input and output sides are required to be on the same side.

In this embodiment, the output shaft 11 passes through the input shaft 2, but this may be reversed so that the input shaft 2 passes through the hollow hole 11a of the output shaft 11 ( (See FIG. 7, which shows a modification of the second embodiment).

In addition to the various embodiments described above, this invention also includes the following modifications.

(b) If the planetary shaft 5 is supported at both ends by the carrier 4 and the rotating body 12 as described above, the stress acting on the planetary shaft 5 can be reduced, but if it is cantilever-supported only by the carrier 4, the stress acting on the planetary shaft 5 can be reduced. Good too.

(b) If the sun gear (fixed gear 9 and output gear 10 in the above description) is an external gear as described above, the external dimensions can be made small, but it may also be an internal gear (the (See Figure 7).

(c) The planetary shaft 5 may be eccentric to the input shaft 2 so that it intersects with the input shaft 2 instead of being parallel to the input shaft 2. In this case, the gears are not spur gears but bevel gears.

(iv) Although the carrier 4 and the rotating body 12 are formed into a disk shape so as to have good rotational balance, they may also be formed into an arm shape.

(Effects of the Invention) This invention provides a planetary differential gear device incorporating non-circular gears, in which a plurality of planetary shafts, that is, planetary gears, are provided symmetrically with respect to the input shaft, and therefore it has many of the following effects. be.

(A) In particular, since multiple planetary shafts and planetary gears on which fluctuating loads act are arranged symmetrically, these fluctuating loads can be divided into multiple parts, making it possible to reduce the shape of each planetary shaft and planetary gear. In addition, not only can the weight be balanced around the input shaft, but each planetary shaft receives the same reaction force from each planetary gear, so not only the input shaft but also the output shaft and fixed gear receive torsional moments.
It is possible to provide a highly practical device that is not subjected to bending moments, allows the dimensions of each part including the bearing to be reduced, and is highly practical. Furthermore, along with this, distortion in each part is reduced, and transmission efficiency and rotation accuracy are also improved.

(B) By incorporating non-circular gears into the planetary differential gear system, various variations in the rotation angle of the output shaft that cannot be obtained with only one set of non-circular gears can be obtained.
It can be used for automation of various devices. Furthermore, by designing a non-circular gear, it is possible to increase the number of repetitions (number of indexing) during one rotation of the output shaft. It is also possible to improve the acceleration characteristics of the output shaft.

(C) Since the planetary differential gear device itself can perform the deceleration action, there is no need for a separate deceleration means, and it also has a self-flocking function. Furthermore, the input and output shafts can be supported in a straight line, making it convenient to use.

(D) Since only gears are used as the transmission means, the slip ratio is small, and the transmission efficiency does not decrease as in the case of using a camshaft and Geneva means, and the rotation accuracy improves.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing the basic structure of the main parts of this invention, Fig. 2 is a pitch diagram of an example of a non-circular gear in this invention, and Fig. 3 is a diagram showing a case where this non-circular gear is used. FIG. 2 is an input/output angle diagram. Fourth
5 is a pitch diagram of another non-circular gear according to the present invention, and FIG. 6 is a detailed structure of the second embodiment of the present invention. The longitudinal side view shown in FIG. 7 is a schematic diagram showing the modification. FIG. 8 is a schematic diagram showing an outline of a conventional gear device. 1... Planetary differential gear device, 2... Input shaft, 3...
...Casing, 4...Carrier, 5...Planetary shaft,
5a... One end side, 6... Planetary gear, 7... Drive side gear, 8... Driven side gear, 9... Fixed gear, 7
a, 7b, 9c, 9d... pitch wire, 10... output gear, 11... output shaft.

Claims (1)

[Scope of Claims] 1. A planetary gear is rotatably supported on a planetary shaft which is connected at one end side by a carrier fixed to the input shaft and is provided eccentrically with respect to the input shaft. The planetary gear is a planetary differential gear in which a driving side gear and a driven side gear are integrally formed, and the driving side gear meshes with a fixed gear, and the driven side gear meshes with an output gear provided integrally with an output shaft. In the dynamic gear device, the driving side gear and the stationary side gear and/or the driven side gear and the output gear are formed into non-circular gears whose pitch lines are rotationally symmetrical, and the planetary shaft is formed into a rotationally symmetrical shape. A planetary differential gear device using non-circular gears, characterized in that the gears are arranged symmetrically with respect to the input shaft. 2. The input shaft and the output shaft are coaxial with each other, and one of the shafts is shaped like a cylinder with a hollow hole, and the other shaft is passed through the hollow hole. A planetary differential gear device using the non-circular gear according to item 1.