JPS61116125A - Outer race for repro joint - Google Patents

Abstract

PURPOSE:To make finishing time reducible, by letting a cage and an outer race come into contact with each other with a convex strip force in a surface between ball grooves on an inner circumferential surface, while reducing a finishing range of the outer race. CONSTITUTION:A convex strip 3 extending in an axial direction is formed on a surface between ball grooves 2 and 2 on an inner circumferential surface, and a top surface of the convex strip 3 is set down to a contact surface with a cage. That is to say, the cage merely comes into contact with this contact surface, not contact with other parts of the surface between these ball grooves 2. Therefore, if it is within the range of thickness in the convex strip 3, no hindrance acts on operation of a repro joint, supposing that there are somewhat jogs an and around the convex strip, whereby finishing cut for these parts is omissible, thus finishing time is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an actor lace of a reprosion joint.

(Prior Art) A repro joint, which is a constant velocity joint used in the automobile industry, consists of a plurality of balls, usually six, a cage for holding the balls, an outer race, an inner race, and the outer race and the inner race. The ball grooves are arranged in the inner race in a V-shape, that is, they are inclined symmetrically to each other by equal angles with respect to the rotation axis.

Since a portion of the cage comes into contact with the surface between the ball grooves on the inner circumferential surface of the outer race, cutting and finishing have conventionally been performed on the entire inner circumferential surface between the ball grooves.

(Problem to be Solved by the Invention) However, when cutting and polishing the entire inner circumferential surface, the range of cutting and finishing is wide, so it is difficult to obtain sufficient accuracy over the entire surface, resulting in poor durability. There is a problem in terms of noise, and the processing and finishing time is long, resulting in high costs.

Furthermore, even in the case of manufacturing by plastic working, the process is complicated because finishing work is similarly required, which has been a problem.

The present invention is intended to solve the above-mentioned problems in the prior art, and its purpose is to be able to obtain a highly accurate inner circumferential surface more easily and at a lower cost than before, and also to have excellent durability and noise. The goal is to provide an outer lace with less reproding joints.

(Means for Solving the Problems) That is, the outer race of the reflow joint of the present invention has a convex line extending in the axial direction on the surface between the ball grooves on the inner circumferential surface, and It is characterized by having the upper surface as a contact surface with the entire cage.

The radial cross-sectional shape of the protrusions is preferably approximately trapezoidal, rectangular, etc., for example. Although its thickness varies depending on the properties of the joint, it is preferably about Q, 03 to α5. Also, it is easier to manufacture if the width is constant, but it can also be made to vary! stomach. When one groove is formed on the surface between all the ball grooves of a certain width, it is appropriate that the width is about 1/2 to 1/6 of the ball diameter.

In the case of a band-like convex strip, as long as it is continuous in the axial direction, its shape may be straight parallel to or inclined to the axis, or may be bent.

Furthermore, a plurality of thin strip-shaped protrusions may be formed. In this case, the groove between each protrusion can be used as a lubricating oil reservoir, for example. Furthermore, cage-shaped protrusions can be used in combination.

The upper surface of the protrusion is polished or otherwise processed to form a contact surface with the cage. The ball cage only touches the abutment surface formed on the protrusion, and does not touch other parts of the surface between the ball grooves.If the thickness of the protrusion is within the range, there may be some unevenness around the protrusion. Even if such a part exists, it does not interfere with the operation of the repro joint, so finishing work on such a part can be omitted.

(Example) The present invention will be explained in further detail in the following example. Note that the present invention is not limited to the following examples.

FIG. 1 shows an embodiment of the present invention. The figure shows the outer race 1 viewed from the axial direction. Further, FIG. 2 is an enlarged view of a portion A surrounded by a dashed line in FIG. 1, and FIG. 5 is a cross-sectional view taken along line mm. The view seen from direction B in FIG. 3 corresponds to FIG. 1. In this embodiment, one convex strip having a substantially rectangular cross section with a thickness of m=12 iaa and a width of t=7 KK (115 mm of the ball diameter) was formed in the center of each surface between the ball grooves 2.

FIG. 4 shows another embodiment of the portion corresponding to the portion C surrounded by the dashed line in FIG. 3, and shows two protruding strips 3'.

In this case, the groove between the two protrusions 5' can also be used as a grease or lubricating oil reservoir, resulting in even better lubrication conditions.

Comparative example: FIG. 5 is an example of a conventional outer lace.

Moreover, FIG. 6 shows a sectional view taken along the line ■-■ in FIG. 5 of a repro joint in which the outer lace of FIG. 5 is attached to a shaft. In both figures, 4 is the mounting hole, 5 is the eyelid and the connection, 6 is the pole 7 is the shaft, and 8 is the bolt.

As is clear from both figures, since the conventional outer race does not have a protrusion on the surface between the ball grooves, it was necessary to finish this entire surface.

Durability comparison test: Reflow joints using the outer lace of the present invention and conventional ones were attached to a testing machine iC and their durability (durability time) was compared under the same conditions. The durability was improved by about 1 to 30% compared to the previous model, and the noise during the test was also significantly reduced.

(Effects of the Invention) As described above, the outer race of the reflow joint of the present invention is made so that the cage and the outer race come into contact with each other by the ridges formed on the surface between the ball grooves on the inner circumferential surface.
When manufacturing the outer lace, cutting requires only a small finishing range, which shortens finishing time and improves productivity, while also reducing wear on cutting tools and lowering manufacturing costs. Particularly in the case of manufacturing by plastic working, by fully forming the convex stripes, it is possible to prevent the occurrence of cracks at the part where the mold is divided between the ball groove molding die and the mandon, so there is no need for finishing work by polishing the inner peripheral surface of the outer race. It can be done.

In addition, because there are fewer surfaces to finish, it is easier to obtain a contact surface with the cage that is more precise than before, and it is also easier for lubricants such as grease to enter the contact surface from the recesses around the protrusions. The lubrication conditions have been improved and wear loss between the outer race and the cage has been reduced, so the life of the reflow joint has been extended and noise has also been reduced.

Furthermore, the formation of the protrusions can be applied not only to repro joints but also to joints with different properties, such as double offset joints with straight grooves and bar-filled joints with arcuate grooves, and has various effects.

[Brief explanation of drawings]

Fig. 1 is a front view of an embodiment of the reflow) N Indian actor race of the present invention as seen from the axial direction, Fig. 2 is an enlarged view of the part A surrounded by the dashed line in Fig. 1, and Fig. 3 The figure is a cross-sectional view taken along the line ■-■ in FIG. A front view of an example of the outer race viewed from the axial direction, and FIG. 6 is a sectional view of a conventional reflow joint. In the figure, 1.1'...Outer race 2...Ball groove 3.
3'... Convex line 4... Hole for installation 5... Gauge 6... Ball 7... Shaft 8... Bolt Patent applicant Toyota Motor Corporation Figure 1 r'hIIr; i 3 r1t+ Figure 4 Figure 5 "4 = e r:1 b

Claims (1)

[Claims] 1. An outer race for a reprosion joint, characterized in that a protrusion extending in the axial direction is formed on a surface between ball grooves on an inner circumferential surface, and the upper surface of the protrusion is used as a contact surface with a cage.