JPS5842397B2 - Dust prevention device for floating internal gear set - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dust prevention device for a power transmission mechanism having an automatic tension adjustment function for a power transmission band such as a belt including a set of internal gears. The internal gear of the transmission mechanism is such that the internal gear meshes with the external small gear in a floating state without providing a This invention relates to a dust prevention device for the meshing part of a gear set.

In such a mechanism, there is a gap between the internal gear and external pinion gear that mesh in a floating state, so if dust or foreign matter or rainwater enters this gap from the outside, the teeth may be damaged. There were problems such as poor lubrication and accelerated tooth wear.

The present invention has been made to solve these problems, and by blocking the gap in the meshing part of the gear set from the outside with a closing plate, it prevents foreign matter and rainwater from entering the meshing part, and improves the meshing. The purpose is to protect the lubricant such as grease applied to the gears for a long period of time to minimize wear on the tooth surfaces, and also to prevent damage to the teeth due to biting of foreign objects and stabilize gear meshing. It is.

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

In the figure, 1 is a driving vehicle, 2 is a driven vehicle, and 2a is this driven vehicle 2
3 is an externally toothed small gear that meshes with the internal teeth 2a, 4 is a toothed belt (cheno belt) which is a transmission band extending around the outer periphery of the driving wheel 1 and the driven wheel 2. ).

3 to 5 show a first embodiment of the present invention, which has hollow disc-shaped closing plates on both sides of an externally toothed pinion 3, which are in sliding contact with both sides of an internally toothed gear 2. 5.

In the figure, 3a is the shaft of the external small gear 3, and 6 is the collar 7 fitted to the shaft 3a, which is a retaining ring.

6 to 9 show a second embodiment of the present invention, in which a hollow disc 8 having a hole 8a into which the shaft 3a of the external pinion gear 3 is loosely fitted is bolted onto both sides of the internal gear 2. 9 and a nut 10, and a hollow disc-shaped closing plate 11 that overlaps and slides on the hollow disc 8 is attached to the shaft 3a on both sides of the external pinion gear 3 through a collar 6 and a retaining ring 7. This is what I installed.

In the above embodiment, a case has been described in which the shaft 3a of the external pinion gear 3 protrudes from both sides. However, if the shaft 3a of the external pinion gear 3 is supported in a cantilever manner, the shaft 3a
The open end side without a should be closed only with a circular plate without holes.

Next, the effects of the apparatus of the present invention constructed as described above will be explained.

A driven wheel driven by a driving wheel 1 and a toothed belt 4 (
Since the internal gear (internal gear) 2 does not have a shaft itself, the internal gear 2, which is a driven wheel, is internally meshed with the external pinion gear 3 in a floating state, so the center of rotation of the driven wheel 2 is is external pinion gear 3
The rotation center of the driven wheel 2 is eccentric with respect to the rotation center of the externally toothed small gear 3.

Therefore, the closing plate 5 slides on the side surface of the internal gear 2, and the closing plate 11 slides on the hollow disc 8 fixed to the internal gear 2.
In either case, the gap between the internal gear 2 and the external small gear 3 can be isolated from the outside, so the present invention prevents foreign matter and rainwater from entering the meshing part of the internal gear set. By preventing this, excellent effects can be obtained in that damage to the teeth can be prevented, wear can be reduced, and the durability of the internal gear set can be improved.

In the embodiment of the present invention, the external pinion gear 3 is used as the final drive side, but the same effects can be obtained even when the external pinion gear 3 is used as the driving side.

[Brief explanation of drawings]

Figure 1 is a front view of the transmission mechanism with automatic tension adjustment function;
Fig. 2 is a sectional view taken along the line A-A, Fig. 3 is a front view of the driven side of a transmission mechanism with an automatic tension adjustment function incorporating the dustproof device of the present invention, and Fig. 4 is a sectional view taken along the line B-B. FIG. 5 is a front view of the closing plate, FIG. 6 is a front view of essential parts showing another embodiment of the present invention, FIG. 7 is a cross-sectional view taken along line C-C, and FIG. 8 is a front view of the hollow disk. , FIG. 9 is a front view of the closing plate. 1... Drive wheel, 2... Driven wheel (internal gear), 3...
・・External pinion gear, 3a・shaft, 4・toothed belt (
transmission band), 5... closing plate, 6... collar 7...
Retaining ring, 8...Hollow disc, 9...Bolt, 10...
・Natsuto, 11...occlusion plate.

Claims (1)

[Scope of Claims] 1. A transmission band is passed between a driving wheel and a driven wheel, and either the driving wheel or the driven wheel is an internally toothed gear, and this internally toothed gear is floating on an externally toothed pinion. In a transmission mechanism that automatically adjusts the tension of a transmission band by meshing with each other, a closing plate is attached to the side surface of the gear set of the internal gear and the external pinion to isolate the gap between the two gears from the outside. A dustproof device with a floating internal gear set. 2. The dust-proofing device for a floating internal gear assembly according to claim 1, wherein a closing plate is provided on both sides of the external pinion gear, each slidingly contacting both side surfaces of the internal gear.