JPS6215547Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a spline joint used, for example, in an automobile transmission.

Conventionally, as a transmission using this type of spline joint, one shown in FIG. 4 has been implemented. 1 is a hub attached to the output shaft 2 via a spline 3; 4a and 4b are attached to the hub 1 in the axial direction 5;
First gears are mounted on both sides via needle bearings 6, and these first gears 4a, 4b are always meshed with second gears 8a, 8b mounted on the input shaft 7. Moreover, spline pieces 10, 10 having dog teeth 9, 9 are attached to the first gears 4a, 4b inwardly in the axial direction 5, and the spline pieces 10, 1
a ring gear 12 with synchronizing surfaces 11, 11 at 0;
12 is loosely fitted. 13 is arranged to mesh with a gear on the outer periphery of the hub 1, and the change lever 1
The sleeve is shifted by 8.

By the way, when attaching the spline pieces 10 to the first gears 4a, 4b, in order to prevent movement in the axial direction 5 and rattling in the radial direction 14, the inner surfaces of the spline pieces 10, 10 and 1st
Splines were formed on the outer surfaces of the fitting portions 15, 15 of the gears 4a, 4b, respectively, and the splines were fitted in a crimped state by shrink fitting. That is, as shown in FIG. 5, a spline piece 10 heated to 170° C. is manually splined to the fitting portion 15 of the first gears 4a, 4b, and then press-fitted and fitted using a press. Ta. At this time, in order to facilitate spline alignment between the spline piece 10 and the fitting portion 15, a conical chamfer (see FIG. 6) with an angle α is formed on the end of the spline 16 of the spline piece 10, and the fitting portion 15 is Spline alignment is performed by placing the spline piece 10 on the part 15 and rotating it in the circumferential direction by hand.
At this time, if there is misalignment (radial misalignment) between the spline piece 10 and the fitting part 15, an inclination will occur between the two due to the chamfering, making spline alignment extremely difficult and time consuming. At the same time, if the alignment is insufficient, the press fit will be poor and the product will be defective.

This invention was made to eliminate the above-mentioned drawbacks, and by forming a circular arc surface of a predetermined shape on the spline end of the outer cylinder such as a spline piece, the spline fitting between the outer cylinder and the inner cylinder is improved. It is an object of the present invention to provide a spline joint that can be easily performed and hardly produces any defective products.

An embodiment of this invention will be described below with reference to the drawings. Note that the same parts as in FIGS. 4 to 6 are designated by the same reference numerals, and the explanation thereof will be omitted. In FIG. 1, 10 and 10 are spline pieces as an outer cylinder, 15 and 15 are fitting parts formed on first gears 4a and 4b as inner cylinders that are fitted into this outer cylinder, and the spline pieces are Splines are formed on the inner surfaces of the pieces 10, 10 and the outer surfaces of the fitting portions 15, 15, respectively. Further, as shown in FIG. 3, the spline 1 of the spline piece 10 is
An arcuate surface 17 having a radius of curvature that is approximately the same as the tooth height of the spline 16 is formed at the sixth end.
This arc surface 17 has an arc shape in a cross section including the central axis of the spline piece 10 (the cross section shown in FIG. 3), and has a curvature at approximately the same 20 positions in the radial direction as the tips 16a of the splines 16 of the spline piece 10. The tooth tip 1 has a center 21 and a radius of curvature R that is almost the same as the tooth height H of the spline 16.
The fitting direction 2 of the spline piece 10 into the fitting part 15 goes from 6a to the root 16b.
It protrudes smoothly to 2.

In connecting the spline pieces 10, 10 and the fitting portions 15, 15 of the first gear 4a in a crimped state via the spline 16, as shown in FIG. 2, as in the conventional case, This is done by placing the heated spline piece 10 on the fitting part 15 of the first gear 4a, manually rotating the spline piece 10 in the circumferential direction to align the splines, and then press-fitting with a press. .

By the way, since an arcuate surface 17 is formed at the end of the spline 16 of the spline piece 10, as clearly shown in FIG. is done smoothly. In other words, the end of the spline 16 is cut off at a right angle without a chamfer.
In this case, instead of eliminating the guide part for spline fitting, the spline piece 10
Even if the fitting portion 15 and the fitting portion 15 are shifted in the radial direction 20, there is no inclination between the two 10 and 15, whereas the conventional chamfering, that is, the spline 1
When the conical surface 25 is provided concentrically with the spline piece 10 and the fitting part 15, the spline piece 10 and the fitting part 15 are arranged in the radial direction 20
If the conical surface 25 is misaligned, when the conical surface 25 hits the tip of the fitting portion 15, an inclination as shown by the two-dot chain line will occur between the two 10 and 15. On the other hand, the arcuate surface 17 of this invention has an intermediate shape between the perpendicular cut-off surface 24 and the conical surface 25, so it can smoothly guide the two when spline fitting is performed.
Even if there is a deviation of 20 in the radial direction between 0 and 15,
This inclination can also be suppressed. As a result, spline fitting for spline fitting requires almost no time, and simply by placing the spline piece 10 on the fitting portion 15, the spline piece 10 can be easily press-fitted with a press.
can be connected, and there are almost no defective products.

As explained above, according to this invention, by forming a circular arc surface of a predetermined shape at the spline end of the outer cylinder, spline fitting between the outer cylinder and the inner cylinder is easy, and there are almost no defective products. Spline fittings can be provided. The present invention can also be applied to ordinary spline fittings that do not require shrink fitting.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of this invention.
Fig. 2 is an explanatory diagram showing spline fitting in the same embodiment, Fig. 3 is an enlarged sectional view showing the main parts of the same embodiment, Fig. 4 is a longitudinal sectional view showing the conventional example, and Fig. 5 is the conventional example. Explanatory diagram showing spline fitting in, No. 6
The figure is an enlarged sectional view showing the main parts of a conventional example. 10... Spline piece (outer cylinder), 15...
Fitting part (inner cylinder), 16... Spline, 17...
Arc surface, 20...radial direction, 21...center of curvature, 2
2...Fitting direction, H...tooth height, R...curvature radius.

Claims (1)

[Scope of utility model registration request] In a spline joint, in which splines are formed on the inner surface of an outer cylinder and the outer surface of an inner cylinder fitted to the outer cylinder, and the outer cylinder and the inner cylinder are connected by spline fitting, the spline end of the outer cylinder A circular arc surface having an arc shape is formed in a cross section including the central axis of the outer cylinder, and this circular arc surface has a center of curvature at a radial position approximately at the same position as the tooth tips of the splines of the outer cylinder,
A spline joint characterized in that it has a radius of curvature that is almost the same as the tooth height of the spline, and that it smoothly protrudes in a direction in which the outer cylinder is fitted into the inner cylinder from the tooth tip to the tooth base.