JPS5842382B2 - Trochoid Kei Hagata Hagurumao Yuusei Hagurumatoshita Gensokuki - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speed reducer in which a trochoidal tooth gear with a plurality of teeth differences between an external gear and an internal gear is used as a planetary gear.

As shown in FIG. 1, a conventional speed reducer that uses a trochoidal tooth gear as a planetary gear runs through a fixed internal gear 1 consisting of an arcuate tooth profile with rolling elements 10 arranged at equal pitches on the inner periphery via roller bearings 11. When the external gear 3, which is held by the eccentric wheel 2 and whose tooth profile curve is an evitrochoid curve in which the radius ratio of the rolling circle and the base circle is an integer, is eccentrically rotated, and the rotational angular velocity of the eccentric wheel 2 is ω1, the external gear 3 rotates in the opposite direction at ω2.

That is, the external gear 3 revolves at a high speed ω1 and simultaneously rotates at a low speed ω2.

In a reducer using this trochoid tooth gear as a planetary gear, the number of teeth of the internal gear is 1 compared to the external gear to avoid tooth profile interference.
More copies are given.

Therefore, the gear ratio (the negative sign is because the direction of rotation is opposite), where P: number of teeth of external gear, S2 number of teeth of internal gear, and
The rotation ω2 of the external gear 3 is extracted by the rotation extraction means to perform deceleration.

In the reduction gear using the conventionally known trochoid tooth gear as a planetary gear, the following conditions must be satisfied.

1. The number of teeth on the external gear is always one less than the number of teeth on the internal gear.

2. Radius d of the circle that creates the Evitrochoid curve of the external gear
and the teeth of the internal gear (usually configured as an outer pin with a pin or an outer roller with a roller on the pin)
have the same radius.

3. The pitch circle radius of the external pin row must be equal to the sum of the radii of the Ebitrochoid creation base circle and rolling circle of the external gear.

Assuming that such conditions are satisfied, once the combination of the external pin, which is the tooth of the internal gear, and the eccentric wheel is determined, the shape of the external gear that meshes with this is uniquely determined.

However, in the low reduction range, the number of effective meshes between the external gear and the internal gear is small, and therefore the demand for a reduction gear with a low reduction ratio, small size, and large transmission capacity cannot be met.

The present invention improves the above-mentioned drawbacks and provides a completely new tooth profile curve for an external gear.

An example of this will be explained with reference to FIG.
1/2 pitch relative to the pitch of the teeth) and overlap.

Then, the curved part 6 inside the overlapping curved parts
(The shaded part in the figure) is the tooth profile curve of the external gear.

FIG. 3 shows another embodiment of the present invention, in which ebittrochoidal curves 7 and 8 having an odd number of peaks are similarly changed in phase to 1.
They are overlapped with a shift of 80' (V2 pitch with respect to the tooth pitch), and the curved portion 9 is the tooth profile curve of the external gear.

FIG. 6 shows an example of a reduction gear in which the curved portion 9 of FIG. 3 is used as the tooth profile curve of the external gear.

Fig. 6 shows Fig. 4 and Fig. 5 (Fig. 4 and Fig. 5 are reducers whose external gear tooth profiles are the evitrochoid curves 7 and 8, respectively, whose phases are shifted by 1800 degrees) for each external gear and internal gear. For overlapping external gears, the curved portion 9 on the inside of the overlapping curved portions is the tooth-shaped curve, that is, the overlapping outside curved portion is excluded.

To explain the reducer shown in Fig. 6 below, each of the two ebitrochoid curves 7 and 8 is closed because the radius ratio of the inversion circle and the base circle is an integer, and therefore, in Fig. 6, there are 24 circular arcs. If we pay attention to one of the tooth profiles, one of the ebittrochoid curves 7
The arcuate tooth profile that meshes with the other Ebitrochoid curve 8 does not mesh with the other Ebitrochoid curve 8.

That is, every other 24 arcuate tooth profiles in FIG. 6 mesh with the same ebitrochoid curve (7 or 8), and adjacent arcuate tooth profiles do not mesh with the same evitrochoid curve.

Here, if we look at FIG. 3 to see that the ebitrochoid curves are overlapped and the overlapping outer parts are removed, the outer part of one ebitrochoid curve 8 that overlaps with the other ebitrochoid curve 7 is the ebitrochoid curve 7. Since it interferes with the circular tooth profile that meshes and moves along this, this interfering part must be removed.

In this way, the only problem is where one of the ebitrochoid curves 7 and the circular tooth profile that meshes with it interferes with the other ebitrochoid curve 8. It has nothing to do with the relative movement of the circular arc teeth that mesh with the tooth.

As described above, the gears in Figure 6 mesh normally as gears, and the reduction ratio is 1/11, the same as the conventional gears in Figures 4 and 5, but the number of effective teeth is It has an extremely excellent effect of increasing the amount of water compared to the conventional one.

In the above, the case where the phase shift of the two evitrochoid curves is 1/2 pitch has been explained, but it is also possible to have a phase shift of 1/3 pitch, similar to the above-mentioned 1/2 pitch. By stacking the external and internal gears with a 1/3 pitch shift from each other, normal gear meshing can be achieved as explained above in the case of 1/2 pitch, and the reduction ratio is the same as before. A reduction gear with an increased number of effective teeth can be obtained.

Figure 8 shows an evitrochoid curve 12 with an odd number of peaks.
．． 13 by 1/3 pitch relative to the pitch of the teeth.
The inner curved portion 14 is shown as a tooth profile curve of an external gear, and FIG. 9 shows an example of a reducer in which the tooth profile curve 14 is used as the tooth profile of an external gear.

In the embodiments shown in FIGS. 2 to 6 and 8 to 9 of the present invention, two ebitrochoid curves are superimposed, but in general, trochoid curves with n teeth are separated by an equal phase angle. They can be stacked at different angles (equally spaced with respect to the pitch of the teeth), and may also be shifted so that they have unequal phase angles (distantly spaced with respect to the pitch of the teeth). It is something.

In this case, the peaks (number of teeth) of the superimposed curves are in (
i is the number of overlapping), and the number of internal teeth is roughly i(n+1
) pieces.

Therefore, the difference in the number of teeth is i(n+1)-in=i.

becomes.

That is, the difference in the number of i teeth can be arbitrarily selected.

In terms of design, it is practical to set the number of outer pins or outer rollers to an even number, and in this case, if the outer pin row is divided by diameter, the outer pin row will be highly symmetrical.

Therefore, the rotational force is transmitted in a well-balanced manner.

Note that the outer roller has better wear resistance than the outer pin, increasing the durability of the device.

As described above, the present invention superimposes a plurality of ebitrochoid curves in which the radius ratio of the inversion circle and the base circle is an integer with a phase shift, and removes the innermost curve portion of the overlapping individual curves. By making the tooth profile curve of the gear, the fourth to sixth
Figure (Figure 6 is formed by overlapping Figures 4 and 5.

), compared to the conventional model with a difference in the number of teeth of 1, the number of meshing teeth effective for power transmission increases under the same diameter and the same reduction ratio, and even though the tooth width is the same, It is the same as if the width were increased by i times, and the tooth surface strength is improved and the transmission capacity is improved.

Therefore, it has the excellent effect of providing a reduction gear with a low reduction ratio, a small size, and a sufficiently large transmission capacity.

Furthermore, it is possible to obtain a reduction gear in which a trochoid tooth gear with a different speed ratio is used as a planetary gear simply by replacing the external gear without changing the internal gear side.
(See Figures 6-7).

It should be noted that it is preferable in terms of design that the deviations when the evitrochoidal curves are superimposed according to the present invention be at equal phase angles (equal intervals with respect to the pitch of the teeth), and also due to the balance of the transmitted torque and the arrangement of the outer pin or outer roller. It is practical from this point of view.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram for explaining a reduction gear that uses a conventional trochoidal tooth gear as a planetary gear, and Fig. 2 is a superimposed line of tooth profile curves of external teeth having an even number of peaks shifted by 180°. Figure 3 is a diagram in which the tooth profile curves of external teeth having an odd number of peaks are superimposed with a 180° shift, and Figures 4, 5, and 7 respectively show conventional reducers. FIG. 6 is an explanatory diagram of the main parts showing the reduction gear of the present invention. FIG. 8 is a diagram showing tooth profile curves of external teeth having an odd number of peaks shifted by 1200 and superimposed. FIG. 9 The figure is an explanatory diagram of main parts showing the reduction gear of the present invention. Explanation of symbols: 1: Internal gear, 2: Eccentric wheel, 3: External gear.

Claims (1)

[Claims] 1 In an internally meshing planetary gear reducer in which the fixed internal gear has a circular arc tooth profile and the planetary external gear has a trochoidal tooth profile, the planetary external gear has a radius ratio of a rotation circle to a base circle. An inner M metal type planetary gear reducer in which a plurality of evitrochoidal curves, in which is an integer, are superimposed with a phase shift, and the innermost curved portion of the superimposed individual curves is a tooth profile curve.