JPS626536Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotation take-out device for a traveling speedometer of a motorcycle or the like, in which a gear housing is molded of synthetic resin.

As shown in FIG. 1, this type of device consists of a gear housing 1 fixedly attached to a wheel shaft 11, and a gear device 2 provided within the gear housing 1. The gear housing 1 has an oil seal engaging cylinder. The cylindrical portion is fitted with an oil seal 5 provided on the wheel hub 4, and the gear housing 1
Gear device 2 parts and wheel hub bearing 6
This prevents dust, muddy water, etc. from entering the area. The gear device 2 also includes a gear 2a that is connected to and rotates with the wheel hub 4, and a pinion gear 2 that meshes with the gear 2a to rotate at a desired reduction ratio and transmits the rotation to the outside.
It consists of b.

By the way, when the gear housing 1 of this type of device is molded from synthetic resin, as shown in FIG. Shrinkage of the built-in part during molding affects the oil seal engaging cylindrical part 3, and the roundness of the oil seal engaging cylindrical part 3 is significantly reduced, making it impossible to rotate and slide smoothly with the oil seal 5. ,
This has caused problems such as dust, muddy water, etc. entering the gear device 2 and the wheel hub bearing 6. If the gear housing 1 is made thicker in order to improve its strength, this phenomenon becomes more noticeable. This problem was considered to be unavoidable in the gear housing 1 made of synthetic resin.

The present invention was developed in consideration of these points, and is a travel speedometer with a synthetic resin gear housing that improves the sealing performance between the oil seal and the oil seal engaging cylindrical part and reliably prevents the intrusion of dust, muddy water, etc. The purpose is to provide a rotary take-out device for
The present invention will be explained below based on the accompanying drawings.

Figures 3 and 4 show examples of the present invention.
In the drawing, a large number of holes 8 are provided in a flange end surface 7 extending radially from the oil seal engaging cylindrical portion 3 of the gear housing 1 . For this reason, when the gear housing 1 is molded from synthetic resin, the large number of holes 8 alleviates the shrinkage and warpage of the synthetic resin, so the oil seal engaging cylindrical portion 3 is not affected by the shrinkage of the bump portion 10 during molding. It is possible to obtain extremely high roundness without being exposed to dust, improve the sealing performance between the oil seal and the oil seal engaging cylindrical part 3, and reliably prevent the intrusion of dust, muddy water, etc. . Furthermore, by providing the holes 8 all around the end face 7 of the flange, warping of the flange can be alleviated. Further, since the hole 8 is simply provided in the flange end face 7, the strength of the gear housing 1 can be made comparable to that of conventional products.

As described above, the present invention provides a rotation take-out device for a speedometer in which the gear housing is made of synthetic resin, the end face of the flange extending radially from the oil seal engaging cylindrical part of the gear housing, or the end face of the flange at least near the knob part. The oil seal engaging cylindrical part is provided with a large number of holes, so when the gear housing is molded from synthetic resin, the large number of holes alleviates the shrinkage and warping of the synthetic resin. Extremely high roundness can be obtained without being affected by shrinkage during molding, and the sealing performance between the oil seal and the oil seal engaging cylindrical part is improved to reliably prevent the intrusion of dust, muddy water, etc. You can. or,
By providing holes all around the end face of the flange, warping of the flange can be alleviated. Further, since the hole is simply provided in the end face of the flange, the strength of the gear housing can be made comparable to that of conventional products.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of a rotation take-out device for a traveling speedometer showing a conventional example, Fig. 2 is a side view of a gear housing, Fig. 3 is a longitudinal cross-sectional view of a gear housing showing an embodiment of the present invention, and Fig. 4 FIG. 3 is a side view of the gear housing of FIG. Explanation of symbols 1... Gear housing, 2... Gear device, 3... Oil seal engaging cylindrical part, 4... Wheel hub, 5... Oil seal, 7... End face of flange, 8... Hole, 9 ...Cylindrical part, 10...Nump part.

Claims (1)

[Scope of utility model registration request] A gear housing 1 made of synthetic resin has an oil seal engaging cylindrical portion 3 that is fixedly attached to a wheel shaft 11 and that engages with an oil seal 5 provided on a wheel hub 4; and a gear device 2 for transmitting the rotation of the hub 4, and the gear housing 1 is connected to the gear 2.
In the rotation take-out device for a traveling speedometer, which has a substantially cylindrical portion 9 containing a cylindrical portion 9 and a knob portion 10 containing a pinion gear 2b, a cylindrical portion 9 extending radially from the oil seal engaging cylindrical portion 3 of the gear housing 1 is provided. A rotation take-out device for a traveling speedometer, characterized in that a large number of holes 8 are provided in the flange end surface 7, at least in the vicinity of the bump portion 10.