JP2000240738A - Gear transmission having variable number of tooth - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a continuously variable transmission having gear characteristic by equally dividing a conical surface or a wall surface on a disk, and providing each sector with a gear having the same pitch. SOLUTION: A matching function in the case where torque and the number of revolution of a load such as a motor for automobile do not match with these of an engine is provided. In a conical pattern gear 2, a loose-out of tooth is generated at a position, in which the number of tooth is changed. Since there is a tooth, of which tooth arrangement and traveling direction are displaced from a right angle, in each sector, it is necessary to provide the tooth with a play. Trouble of loose-out of tooth can be avoided by using a gear having a relatively large radius so that two or more teeth are always engaged with each other, or using a geared belt. Position of a receiver tooth is continuously changed by a position changing mechanism 9 for irregularity. With this structure, an approximately continuous transmission capable of restricting the energy loss at the minimum can be thereby realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanism for continuously changing the rotational speed of power.

[0002]

2. Description of the Related Art Various types of continuously variable transmissions utilizing a combination of a conical pulley and a normal pulley, changing the intersection position thereof, and changing the effective pulley size have already been put to practical use. However, all of them are inferior in torque and energy efficiency as compared with the gear type. (Fig. 1)

[0003]

If the number of gears can be changed, a continuously variable transmission having the characteristics of gears should be made. Because the number of teeth is an integer, it cannot be changed completely continuously, but we devised a gear mechanism that works close to that,
An approximately stepless transmission is realized.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to configure a transmission by changing the number of teeth of a gear on a shaft and meshing with each other. First, considering a friction type transmission, the transmission can be easily configured by combining a conical pulley and a position-movable pulley as shown in FIG. The same thing can be realized by a gear system if there is a gear with a variable number of teeth. However, the number of teeth cannot be continuous because it is an integer (digital), but it can be approximately continuous. This is the gist of the present invention. FIG. 2 shows the principle. The conical surface or the wall surface on the disk is divided into several equal parts, and a gear of equal pitch is cut into each sector. Hereafter this is SURI
It is called a BACHI pattern. This pattern is similar to the slash pattern, except where the peak-to-peak spacing is less than one tooth, with the teeth removed.

FIG. 3 shows the gear when viewed on the same circumference. The line segment in the figure indicates the peak of the gear. One missing tooth occurs at the position where the number of teeth changes. Or within each sector,
Since some teeth are displaced from the right angle at the tooth alignment and traveling direction, a speed change occurs, and the teeth of the gears are not parallel, so that it is necessary to provide play to the teeth. The problem of tooth loss can be avoided by using a gear having a relatively large radius so that two or more teeth always mesh with each other, or by using a toothed belt. As an example, FIG. 4 shows the speed change when the whole is divided into 15 ° sectors. In this case, if an appropriate torque filter is provided, it can be put to practical use. This variation can be avoided by making the gear pitch narrower within one sector as the angle increases. On the other hand, play is necessary to change the relative angle of the teeth, but to make the pitch narrower with the larger angle, make the tooth angle match with the larger angle, and slightly shift the smaller angle from parallel deep.
(See FIG. 3C)

The angular position of the gear in the sector is given by θ₁, Θ₂,
θ₃, Tooth pitch L₀, L₁, L ₂・ ・Original
The pitch is constant at l0, the gear passes through with li inclined by θ.
Thus, the effective pitch is as follows: effective pitch = Li / cos θi. Therefore, Li is narrowed by the following equation. L₀= L₀, L₁= L₀・ Cos θ₁, L₂= L₀・ C
osθ₂.... For example, θ₁= 1 ゜. θ₂= 2 ゜ L₀/ L₀= 1, L₁/ L₀= 1 · cos1 ゜, L₂/
l₁= 1 · cos2 ゜ ··· Effective pitch = 1₀ Becomes Originally, the number of teeth was 15
It increases to N months. Last tooth and beginning of next section
Is l₀In the following cases, one tooth is missing. Tooth pitch
Requires a maximum cos 15 $ (0.966) change
You. FIG. 3C shows this relationship. However, the angle relationship
Exaggerated. The above was considered with a disk, but the basic
The same idea applies to cones. This way,
A gear with a variable number of teeth with no speed fluctuation is produced. The only flaw
Is sometimes in this example once every 15 ° (24 per revolution)
Times), the teeth are skipped. Total number of teeth
If it is set to about 300 or more, it is in a practically troublesome range. Ma
If you use a toothed belt with multiple teeth,
Although a little play remains, there is no practical problem.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A matching function is provided when the torque and the number of revolutions required by a load, such as a motor of an automobile, do not always match those of an engine, and an automatic transmission can be easily constructed.

[0008]

FIG. 5 shows an embodiment. An embodiment in which the speed is changed by continuously changing the position of the receiving tooth will be described. FIG.
1 shows an example of a forward / reverse continuously variable transmission. FIG. 7 shows an example of a configuration using an introduction unit by friction at the time of initial connection.

[0009]

According to the present invention, a transmission that is approximately continuous and has very little energy loss can be easily realized.

[Brief description of the drawings]

FIG. 1 is a diagram of a friction type continuously variable transmission.

FIG. 2 is a plan view of a transmission using a continuous-tooth gear.

FIG. 3 is a cutaway view of the same circumference as the SURIBACHI pattern.

FIG. 4 is a diagram showing a change in angular velocity when the pitch between teeth is equal.

FIG. 5 is an embodiment of a transmission.

FIG. 6 is an example of a transmission in which forward / reverse and stop are continuously varied.

FIG. 7 shows an example of a configuration using an introduction unit based on friction at the time of low-speed connection.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drive shaft 2 SURIBACHI pattern gear 3 Load shaft 4 Spur gear 5 Sector 6 Tooth missing 7 Load shaft gear 8 Sector boundary 9 Position variable mechanism 10 Reverse drive 11 Static teeth 12 Toothless part 13 Friction pulley 14 Friction pulley 15 Friction pulley stopper

Claims (2)

[Claims] 1. SURIB on a conical or disk-shaped wall
The gears of the ACHI pattern are cut to make a gear whose number of teeth changes approximately continuously. 2. A gear or a toothed belt meshing with said gear is provided so that a position meshing with said gear can be changed. The transmission configured as described above.