JPS59140937A - Speed decreasing gear - Google Patents

Abstract

PURPOSE:To prevent strain in a speed decreasing gear for slowing down a rotation by engaging an internal gear with an external gear having a slightly smaller number of teeth than the former and to facilitate the processing of parts, by making the external gear of an annular body comprising rollers and a retainer. CONSTITUTION:An internal gear 1 having cycloid teeth (a) on the inside is secured on a support F. An annular body 2, which comprises rollers 3 for constituting external teeth for the internal teeth (a) and a retainer 4 for the rollers, is provided between the internal gear 1 and a bearing 5 in such a manner that the rollers 3 are engaged with the cycloid teeth (a). An eccentric cam 6 is fitted in the inner race of the bearing 5 and secured on an input shaft 7. The annular body 2 is positioned with an eccentricity so that its rollers 3 are sequentially engaged with the internal gear 1 by the rotation of the cam 6. When the input shaft 7 is rotated, the eccentric cam 6 is turned to move the annular body 2 in the circumferential direction so that a rotation with its speed changed by the difference in the number of teeth between the internal gear 1 and the rollers 3 is transmitted to an output shaft 8.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speed reducer that reduces rotation by meshing a seven internal gear with an external gear having a slightly smaller number of teeth.

Conventional reduction gears of this type include planetary gear mechanisms and harmonic drive mechanisms, but planetary gear mechanisms have a complicated structure, and harmonic drive mechanisms transmit large forces while constantly generating flux in mechanical parts. There are problems such as the need for advanced processing technology as it is necessary to perform this process.

The present invention aims to provide a speed reducer that solves the above problems by using an external gear as an annular body composed of a roller and a retainer.

The present invention will be described below with reference to embodiments shown in the drawings.

FIG. 1 is a schematic diagram of a reduction gear according to the present invention, and FIG. 2 is a cross-sectional view thereof. In the figure, (1) is an internal gear fixed to the support member (FIG. 2F) and has cycloid teeth (a) on its inner periphery, and (2) is each roller (3) that constitutes the external tooth relative to the internal tooth. It is an annular body consisting of a retainer (4) and a retainer (4) that holds it. This annular body (2) is provided between the internal gear (1) and the bearing (5) so that the roller (3) and the cycloid teeth (a) mesh with each other.
The number of teeth is slightly smaller than the number of cycloid teeth (a).

(6) is fitted into the inner ring of the bearing (5) and is held integrally with the input shaft (7), and its rotation causes the roller (3) to sequentially mesh with the internal gear (1). 2) Eccentric cam (biasing mechanism) that biases in the radial direction
.

(8) is an output shaft integrally connected to the retainer (4).

The operation of the reduction gear configured as described above will now be described.

First, when the input shaft (7) is rotated by an external input (not shown), the eccentric cam (6) rotates, and its long shaft portion engages the inner roller (3) of the annular body (2). The cycloid teeth (a) of the gear (1) are brought into mesh with each other, and the annular body (2) is sequentially moved in the circumferential direction. Although this movement rotates in the opposite direction to the input shaft, this movement is transmitted to the output shaft.

Further, the movement of the annular body (2) in the circumferential direction is controlled by the number of teeth of the internal gear (1) and the roller (
3) A difference in rotation will occur due to the difference in the number of parts.

The output shaft (8) is transmitted with a rotational speed that is changed by the difference in the number of teeth between the two gears and rotates once.

As described above, the rotation of the input shaft (7) is decelerated and taken out to the output shaft (8).

Although the present invention has been described above, its configuration is not limited to the above and illustrated examples; for example, it is also possible to have a configuration in which the output shaft is connected to an internal gear and the retainer is fixed to a fixed part. It is. In addition to the cam mechanism, the biasing mechanism may be of a single-circular arm type, and is not limited to the illustrated example.

Since this invention is as explained above, since the gears have 9 rollers in contact with each other, there is no distortion in the transmission mechanism, and since a retainer and rollers are used, the structure is simple and the parts can be easily processed. This provides an excellent reduction gear.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a reduction gear according to the present invention, and FIG. 2 is a cross-sectional view thereof. (1)...Internal gear (2)...Annular body (3)・
...Roller (4) ...Retainer (6) ...Eccentric cam (7) ...Input shaft (8) ...Output shaft

Claims (1)

[Claims] an internal gear, an annular body disposed inside the internal gear, held in isolation by a retainer, and having a smaller number of rollers than the number of teeth of the internal gear; and a biasing mechanism for biasing the annular body in the radial direction so that the roller of the body is engaged with the internal gear in the 111st order, and the internal gear or the retainer is connected to the output shaft, and the biasing mechanism is connected to the input shaft. A speed reducer characterized in that the speed reducer is configured to be connected to each other so that rotation of an input shaft can be decelerated and output to an output shaft.