JPS6182046A - Planetary gear reduction apparatus - Google Patents

Abstract

PURPOSE:To reduce the meshing gear noise between a planetary gear and an internal gear by forming a convex part onto the internal gear through high- polymeric resin mold method and fitting said convex part to a concaved part formed integrally with a case body. CONSTITUTION:An internal gear 8 onto which a projection part 9 is integrally arranged is obtained through high-polymeric resin mold method. Further, a case body 10 having a concaved groove 11 is prepared by the casting work in aluminum-alloy die casting. Therefore, the turning force of the internal gear is certainly transmitted onto the case body 10 through the engagement between the projection part 9 and the concaved groove, and since the internal gear is made of resin, the meshing gear noise with the planetary gear can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of an internal gear fixing device for a planetary gear reduction gear.

Conventionally, there has been a device for this dish as shown in the MR diagram.

In the figure, (1} is a planetary gear supported on a support pin (3) via a sleeve bearing (2), and performs planetary motion as described later. (4) is a sun gear, and (5) is an internal gear. It is a gear (ring gear) and has a fixing pin (not shown) fixed to the housing (not shown) in a concave groove (6) provided on the outer peripheral surface.
The knock pin (7) is engaged, and circumferential rotational force is received.

Next, the operation of the above configuration will be explained. Sun gear (4
A rotational force is applied to the sun gear, and the planetary gear {1} which is urged to mesh with the sun gear revolves around the inner circumferential surface of the internal gear (5) through simultaneous meshing with the internal gear (5). Further support pin (3)
Rotates around the center. Then, the rotational force of the sun gear (4} is transmitted to the support pin (3), and the support pin (3)
It is rotated at a reduction ratio of [where zl is the number of teeth of the sun gear (4) and 2 is the number of teeth of the internal gear (5)], and exhibits the function of a planetary gear reduction device. Note that the fixing pin (7) has a function of receiving the rotational force reaction force generated in the internal gear wheel (5) at this time.

The conventional device is as described above, and the internal gear (5) is fixed by a fixing pin having a reaction force receiving function.
Such a configuration has disadvantages such as an increase in the number of parts of the device and an increase in the number of assembly steps.

This invention eliminates the above-mentioned drawbacks by providing a convex portion in advance on the internal gear using a polymer resin molding method, and attaching the convex portion to a recess formed integrally on the housing using an aluminum alloy die-casting method. This is what I did.

An embodiment of the present invention will be described below with reference to the drawings. Second
In the figure, (8) is an internal gear wheel having a protrusion (9) integrally disposed by a polymer resin molding method, and it is possible to easily obtain the shape shown in the figure. αQ is a housing provided with grooves αη, and can be manufactured extremely easily by aluminum alloy die casting. The rest of the configuration is the same as that of the conventional device shown in FIG. 1, so the same symbols will be used and the explanation thereof will be omitted.

According to the above configuration, 1. Due to the simple 1A configuration, the rotational force of the internal gear is engaged with the protrusion (9) and the recess, reducing the sound of the housing gear. The poor heat transfer of the wheels can be compensated for by making the housing from aluminum, which has good heat conductivity, and a planetary gear reduction gear with good heat resistance and low noise can be obtained.

In addition, if a plurality of the above-mentioned fastening points are provided, a high strength product can be easily obtained.

Further, in the above description, the engaging portion is formed on the outer circumferential surface of the internal gear wheel, but the same effect may be obtained by providing one or more engaging portions on the end surface of the internal gear wheel using the above-mentioned manufacturing method.

As described above, according to the present invention, the protrusions are integrally disposed on the inner teeth by polymer resin molding, the grooves are integrally formed in the housing by aluminum alloy die-casting, and these protrusions are It has the effect that the arrangement of the groove and the groove can be achieved at low cost with an extremely simple structure.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a conventional planetary gear reduction device. FIG. 2 is a sectional view showing an embodiment of the present invention. In the figure, (1) is a planetary gear, (8) is an internal gear, (9) is a protrusion, αQ is a housing, and (2) is a groove. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (3)

[Claims] (1) In a device in which an internal gear constituting a planetary gear reduction gear is fitted and held in a housing, a protrusion is integrally provided on the internal gear by a polymer resin molding method, and the protrusion 1. A planetary gear reduction device characterized in that a concave groove is integrally provided in a housing by an aluminum alloy die-casting method in accordance with the above, and the protrusion and the concave groove are configured to engage with each other. (2) The planetary gear reduction device according to claim (1), wherein the engaging portion is formed on the outer circumferential surface of the internal gear. (3) The planetary gear reduction device according to claim (1), wherein the engaging portion is formed on the end face of the internal gear.