JPS6242738B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to the structure of a press-fitting spline,
Specifically, the present invention relates to a structure of a press-fitting spline that facilitates phase alignment during press-fitting, and thus facilitates press-fitting of the spline.

(Prior art) When press-fitting an external spline formed on a shaft etc. into an internal spline formed in a hole in a boss section,
When press-fitting the tooth surface of the external spline and the large diameter at the same time, conventionally the tooth profile of the external spline was larger than the tooth profile of the internal spline, so the press-fitted parts of the internal spline and external spline overlapped, making phase alignment very difficult. It was hot. Also, since it is difficult to align the two, if you try to press fit the outer spline out of phase with the inner spline,
Since the pressure resistance was large, the press-fitting load was large, and press-fitting was often difficult.

Next, a conventional method for phasing internal and external splines will be explained using a transmission gear and a spline piece used in an automobile transmission. In FIG. 4, the transmission gear 31 has an outer diameter slightly larger than the outer diameter of the spline piece 37, and external teeth 34 and 39 are cut on its outer periphery, respectively. This transmission gear 31 has a spline piece 37
When formed integrally with the external teeth 34 and 39 of both
Since the two parts are close to each other and it is difficult to cut the gears, the two parts are manufactured separately and then joined together as one piece. For this reason, an outer spline 35 having an involute tooth profile is formed on the outer periphery of the small diameter portion 33 of the transmission gear 31, and the shaft hole 40 of the spline piece 37 into which the outer spline 35 is press-fitted is similarly formed. The internal spline 41 of the involute tooth profile is cut. The tooth profiles of the inner and outer splines 41 and 35 are approximately the same, and as shown in FIGS. 5 and 6, the tooth profile of the outer spline 35 is slightly larger than the tooth profile of the tooth groove 42 of the inner spline 41. Cage, tooth 3
6 is provided with a press-fitting allowance B (area surrounded by a dotted line and a solid line in FIG. 6) for the tooth groove 42. For this purpose, an inner
Chamfers 35a and 41a are provided to facilitate press-fitting of the outer spline, but the angles of the chamfers are the same for both.

Therefore, when the outer spline 35 of the transmission gear 31 is press-fitted into the inner spline 41 of the spline piece 37, it is difficult to align the two in phase, as described above.

(Problems to be Solved by the Invention) Therefore, the technical problem to be solved by the present invention is to facilitate phase alignment during press-fitting of splines, and thus facilitate press-fitting of splines.

(Means for Solving the Problem) A technical means for solving the above problem is a press-fitting spline consisting of a spline shaft and a boss having a spline tooth groove, the spline tooth groove having a trapezoidal cross section. In addition to forming the teeth of the spline shaft into a straight tooth profile, the teeth of the spline shaft have an involute-shaped cross section in which the tooth tips have a press-fit allowance to the bottom of the spline tooth grooves and the root parts have play between them and the spline tooth grooves. The press-fit side end of the spline tooth groove of the boss is chamfered at a predetermined angle, and the press-fit side end of the teeth of the spline shaft is chamfered at an angle more acute than the chamfer of the spline tooth groove. By chamfering the spline shaft, when the spline shaft is fitted into the boss, the roots of the teeth of the spline shaft are introduced into the spline tooth grooves before the tips of the teeth.

(Function) The spline tooth groove of the boss and the teeth of the spline shaft have concave and convex chamfers on the press-fit side ends, respectively, so by aligning these chamfers, the boss and spline shaft can be aligned. (axis alignment)
is easily carried out.

When performing phasing of aligned splines, the chamfer on the spline shaft side is sloped at a more acute angle than the chamfer on the boss side. The base portion can be introduced into the spline tooth groove in a meshing state without any pressing force to achieve phase alignment.

Next, when the spline shaft is press-fitted into the spline tooth groove, the press-fit area of the teeth of the spline shaft into the spline tooth groove follows the inclination of the chamfer, from the root part with play to the tip part with press-fit allowance. Since the spline gradually expands, the press-fitting portion can be smoothly press-fitted into the spline tooth groove with less pressing force.

Next, the present invention will be explained based on embodiments shown in the drawings.

1 to 3, a transmission gear 1 of an automobile transmission has a large diameter portion 2.
and a small diameter portion 3 having a smaller diameter than this, the large diameter portion 2 is provided with external teeth 4, and the small diameter portion 3 is provided with an external spline 5, as in the conventional case. The cross-sectional shape of the teeth 6 of the outer spline 5 of the small diameter portion 3 is an involute tooth shape as in the conventional case. Spline piece 7 has large diameter portion 8
External teeth 9 are cut on the outside of the , and the boss hole 1
0 is provided with an inner spline 11 into which the outer spline 5 of the transmission gear 1 is press-fitted. The groove surface 12a of the tooth groove 12 of this internal spline 11 is in a straight line shape unlike the conventional one.

When the outer spline 5 and the inner spline 11 are aligned in phase (see FIG. 3), there is a gap between the tooth tips 6a of the teeth 6 of the outer spline 5 and the groove bottoms 12b of the tooth grooves 12 of the inner spline 11. The press-fitting allowance is approximately the same as the conventional one. However, the inner spline 11
The groove surface 12a of the tooth groove 12 is linear, and when the shape of this groove surface 12a is overlapped with the cross-sectional shape of the tooth 6 of the outer spline 5, it intersects at point P and reaches the groove top 12c. ing. The total press-fitting allowance C is the area surrounded by the tooth 6 and the tooth groove 12 above point P in Fig. 3 (the area surrounded by the dotted line and the solid line), which is smaller than the conventional press-fitting allowance B. It's summery. Further, below the point P, there is a relief part D where the teeth 6 of the outer spline 5 and the tooth grooves 12 of the inner spline 11 do not overlap.

Teeth 1 of inner spline 11 of spline piece 7
3, the end surface of the outer spline of the transmission gear 1 on the side where the teeth 6 are press-fitted is chamfered as in the conventional case (see FIG. 2). The tooth height of each tooth 6 of the outer spline 5 of the transmission gear 1 on the side to be press-fitted into the end surface 7a of the spline piece 7 is inclined and gradually lowered toward the end surface 1a, forming a press-fitting surface 6b. ing. Then, the chamfer angle θ1, which is the angle between the end surface 7a of the spline pea 7 and the chamfered portion 13a of the tooth 13 of the internal spline 11, and the press-fit surface 6b of the transmission gear 1.
The press-in angle θ2 is larger than the press-fit angle θ2, and θ1>θ2. Therefore, when the teeth 6 of the outer spline 5 of the transmission gear 1 are aligned with the tooth grooves 12 of the inner spline 11 of the spline piece 7, the root portions of the teeth 6 of the outer spline 5 align with the teeth of the inner spline 11. It enters inside the groove 12 (the part 14 into which it enters is indicated by diagonal lines in FIG. 2).

In the above configuration, the transmission gear 1 is connected to the inner spline 11 of the spline piece 7.
When the outer spline 5 is aligned, the tip of each tooth 6 of the outer spline 5 will be exposed to the tooth groove 12 of the inner spline 11 of the spline piece 7, so that each tooth 6 of the outer spline 5 and the tooth groove of the inner spline 11 will be aligned. 1
Phase alignment with 2 occurs immediately.

Next, inner spline 1 of spline piece 7
1 is the outer spline 5 of transmission gear 1.
When the outer spline 5 is press-fitted into the inner spline 11 with the phases of Therefore, compared to the conventional method of press-fitting the press-fitting portion into the tooth groove all at once, the press-fitting can be performed with a smaller press-fitting load.

(Effects of the Invention) The present invention has the effect of facilitating phase alignment of press-fitting splines and facilitating spline press-fitting operations.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the phase alignment of the inner and outer splines when the transmission gear and spline piece are press-fitted using the present invention, FIG. Fig. 3 is a view taken along the - line in Fig. 2, Fig. 4 is a cross-sectional view showing the state of phase alignment between the conventional transmission gear and spline piece, and Fig. 5 is an enlarged view of the dashed-dotted line in Fig. 4. , FIG. 6 is a view taken along the - line arrow in FIG. 1...Transmission gear, 5...Outer spline, 6...Teeth, 6a...Tooth tip, 7...Spline piece, 11...Inner spline, 12...
Tooth groove, 12a... Groove surface, θ1... Chamfer angle, θ2
...Press-fit surface angle.

Claims (1)

[Scope of Claims] 1. A press-fitting spline consisting of a spline shaft and a boss having a spline tooth groove, wherein the spline tooth groove is formed into a linear tooth shape with a trapezoidal cross section, and the teeth of the spline shaft are The boss is formed in an involute-shaped cross section with a tip having a press-fit allowance with respect to the bottom of the spline tooth groove and a dedendum thereof with play between the spline tooth groove and the press-fit side end of the spline tooth groove of the boss is chamfered at a predetermined angle, and the press-fit side end of the teeth of the spline shaft is chamfered at an angle more acute than the chamfer of the spline tooth groove, thereby fitting the spline shaft to the boss. A structure of a spline for press-fitting, characterized in that the root part of the tooth of the spline shaft is introduced into the spline tooth groove before the tooth tip part.