JPS6095221A - Universal joint - Google Patents

Abstract

PURPOSE:To eliminate a bearing and reduce the number of parts, by a method wherein the trunnion bearing part of a spider is covered with synthetic resin having a low friction factor, the trunnion bearing part is engaged with the interior of a cap, and the cap is mated with a hole formed in a yoke. CONSTITUTION:A trunnion bearing part 6 is covered with synthetic resin 11 having low friction properties, and an O-ring 12 is located between a cap and a staged part 6a of a bearing part 6 in a condition in which the trunnion bearing part 6 is positioned in holes 7 in a yoke 2, 3. And, as the trunnion bearing part 6 is inserted in the inner surface of a cap 9, the trunnion bearing part is pressed in the hole 7 on the yoke 2, 3. Further, a claw 10 for caulking is caulked to bring the claw into contact with a staged part (b) of the staged projection part of the cap 9. This causes the cap 9 to be secured to the yoke 2, 3 to prevent pulling off of the cap, resulting in elimination of a bearing, reduction of the number of parts, and causes smooth slide contact of the trunnion bearing part 6 with an inner surface 9a of the cap to maintain given properties.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a universal joint, particularly a universal joint used in the steering section of an automobile, and more particularly to a bearing between a trunnion shaft and a yoke in a universal joint generally called a cardan type. Regarding parts.

Conventionally, needle bearings have been used as bearings for this type of universal joint.
Roughness and dimensions must be strictly controlled (combined with the high price of the needle bearing itself and the trouble of assembly, this causes an increase in costs).

Therefore, the present applicant proposed a universal shaft joint using a synthetic resin bearing (see Japanese Utility Model Application Publication No. 58-1.16824).
Because it is constructed by press-fitting a synthetic resin bearing, such as
In addition, due to the low friction characteristic of resin bearings, the bearings are easily removed from the caps, and during use, the bearings are subjected to vibrating sliding contact in the axial direction of the trunnion in addition to rotating sliding contact, and synthetic resin bearings are quickly removed. There was a risk that the bearing would wear out, causing large play, and even damage the bearing.

Further, a lever has also been devised in which the trunnion shaft portion has a tapered surface (see Japanese Utility Model Publication No. 56-22029 and Japanese Utility Model Application Publication No. 56-163820).

However, since the resin bearing has a tapered inner surface,
The molding is extremely troublesome, and there is a risk that the precision will be significantly lower than that of the cylindrical resin bearing mentioned above.Therefore, it is difficult to make sliding contact over the entire surface with the trunnion taper surface, and the This can cause undesirable writhing motion and vibration in the trunnion.

Furthermore, all of the above-mentioned swivel joints use synthetic resin bearings instead of needle bearings, and still require bearings, so the bearings and the assembly of the bearings are expensive and time consuming. Therefore, it was not possible to achieve significant cost reductions.

The present invention has been made in view of the above circumstances, and although it can be manufactured extremely easily and at low cost by eliminating bearings, it maintains a predetermined accuracy over a long period of time, thereby eliminating the above-mentioned drawbacks and improving reliability. The purpose is to provide a high-performance universal joint.

The feature of the present invention is that the trunnion shaft of the spider is coated with a synthetic resin having a low coefficient of friction.
Furthermore, there is a universal shaft joint constructed by fitting and fixing the trunnion shaft portion into a hole formed with a cap.

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the universal joint 1 includes a yoke 2 connected to a driving shaft, a yoke 3 connected to a driven shaft, and a cross-shaped spider 5. Further, the spider 5 has a trunnion shaft portion 6, and holes 7 are bored in the yoke 2 and 3, respectively.
The trunnion shaft portions 6 are respectively fitted through caps 9.

Furthermore, a third hole is provided in the hole 7 portion on the outer surface of the yokes 2 and 3.
As shown in the figure, there are 1 caulking claws in 3 places around it.
0... is formed, and as shown in detail in FIG. A stepped protrusion 9b is formed at the portion.

The trunnion shaft portion 6 has a truncated conical shape, that is, a tapered surface, as shown in FIGS. A synthetic resin 11 having properties is coated.

As shown in FIGS. 1 and 2, with the trunnion shaft portion 6 positioned within the hole 7 of the yokes 2 and 3, the length of the O-ring 1 is interposed between the step portion 6a of the shaft portion 6. Then, the cap 9 is press-fitted into the holes 7 of the yokes 2 and 3 while inserting the trunnion shaft portion 6 into the inner surface 9a thereof. Further, in this state, the caulking claw 10 is caulked and abuts against the stepped portion of the stepped protrusion 9b of the cap 9, thereby causing the cap 9 to tighten its inner surface 9.
The synthetic resin surface 11 of the trunnion shaft portion 6 is slidably fitted onto the yoke 2 and 3 and fixed to the yokes 2 and 3, thereby assembling the universal joint 1. Note that the inner surface 9 of the cap of the trunnion shaft portion 6
It is desirable to apply a lubricant such as grease, molybdenum disulfide or acetylene black to the inner surface of the cap in advance before inserting it into the yokes 2 and 3 of the cap 9.
It is desirable to press and bend the pawl 10 so that an appropriate preload is applied to the trunnion shaft portion 6 when applying the fixing pressure to the trunnion shaft portion 6 .

Since the present embodiment has the above-mentioned configuration, relative sliding movement occurs between the inner surface 9a of the cap 9 and the synthetic resin surface 11 of the trunnion shaft portion 9 due to the use of the universal joint 1. The synthetic resin 11 has low friction characteristics, and is coated on the shaft portion 6 easily and with high precision by powder spraying and, in some cases, polishing.
Because it is manufactured with high precision through milling or cutting, and in some cases, vanilla or grinding, even though the shaft portion 6 and the inner surface of the cap 9a are composed of tapered surfaces, almost the entire length of the shaft portion 6 and the cap inner surface 9a are There is uniform contact over the entire area, and there is smooth sliding contact without causing undesirable movements such as grinding motion and vibration.

Furthermore, since the shaft portion 6 and the cap inner surface 9a are made of tapered surfaces, when inserting the shaft portion 6 into the cap inner surface 9a,
Air is not compressed deep inside the cap, making it easy to insert and align accurately. Combined with appropriate preload, it maintains its performance over a long period of time without causing play. Can be maintained.

As shown in FIG. 7, a groove 6b extending all the way around the trunnion shaft portion 6 is formed, and a portion of the synthetic resin 11 is buried in the groove 6b during coating. may be further ensured.

Furthermore, as shown in FIG. 7, when inserting the cap 9 into the yoke hole 7, the cap 9 is inserted in a loose manner, and an elastic member such as a spring washer is inserted between the cap top 9c and the snap ring 13 fitted into the hole 7. Body 15 j: e contracted,
An appropriate preload between the shaft portion 6 and the cap inner surface 9a may be maintained for a long period of time.

As shown in FIG. 8, the trunnion shaft portion 6 may be formed into a cylindrical shape, and the cap inner surface 9a may also be formed into a cylindrical shape. In this case, the cap 9 can be easily and inexpensively formed by press working. can be manufactured.

As explained above, according to the present invention, since the trunnion shaft portion 6 is coated with the synthetic resin 11 having low friction characteristics,
The trunnion shaft portion 6 should be able to smoothly slide on the cap inner surface 9a and maintain a predetermined performance while not requiring a bearing and reducing the number of parts to achieve a significant cost reduction. Furthermore, since the synthetic resin 11 is coated on the trunnion shaft portion 6, loads such as impact are received by the shaft portion 6 and damage to the resin layer 11 is prevented, and the synthetic resin coating can be applied easily and with high precision. For example, the shaft part 6
Even if the inner surface 9a of the cap is formed with a tapered surface, accurate alignment can be achieved.Furthermore, the synthetic resin 11 is integrated with the shaft portion 6, and the shaft portion 6 is free from sagging due to partial toothing. Coupled with the fact that undesirable movements such as motion and vibration are prevented, a predetermined accuracy can be maintained over a long period of time. As a result of the above effects, it is possible to obtain a highly reliable universal joint 1 that can be easily and inexpensively assembled and manufactured.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the universal joint according to the present invention, Fig. 2 is a sectional view taken along the I[-I[ plane, Fig. 3 is a partial perspective view showing the yoke, and Fig. 4 is a perspective view showing the cap. 5 is a perspective view showing the trunnion shaft portion of the spider, and FIG. 6 is a view showing the trunnion shaft portion, (a) is a longitudinal sectional view, (bl
7 is a sectional view showing a partially modified embodiment, and FIG. 8 is a sectional view showing a further modified embodiment. 1. Universal joint, 2, 3. Yoke, 5. Spigoo, 6. Trunnion shaft, 7. Hole.
9. Cap, 9a... Inner surface, 11. Synthetic resin Applicant Kyowa Sangyo Co., Ltd. (Figure 1) Figure 2 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Procedural amendment (method) % formula % 1 Indication of the case Patent Application No. 203253 of 1983 2 Name of the invention Universal shaft joint 3 Person making the amendment Relationship to the case Patent applicant Address 890 Shimano-cho, Takasaki City, Gunma Prefecture Name (Name) Representative of Kyowa Sangyo Co., Ltd. Precious wood Shumen 4 Agent address 7-39-10 Nishi Kamata, Ota-ku, Tokyo 144
Issue (shipped on January 31, 1982)

Claims (1)

[Claims] [11] In a universal joint consisting of a drive-side and a wave-side yoke and a cross-shaped spider, the trunnion shaft of the spider is coated with a synthetic resin having low friction properties,
Furthermore, the trunnion shaft portion is fitted into the inner surface of the cap, and the cap is fitted and fixed into a hole formed in the yoke to form a universal shaft joint.