JPH0378490B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a yoke for a universal joint, and in particular to a method for pressing a plate material having a base portion of the yoke and yoke portions protruding from both sides of the base portion. In particular, the present invention relates to an improvement in a yoke for a universal joint that includes a base portion and yoke portions rising from both sides of the base portion.

[Conventional technology]

This type of universal joint yoke is used as a part of an automobile steering device, for example, as shown in FIGS. 9 and 10. In this example, a case is shown in which the steering shaft 1 and the steering gear device 2 are connected by a lower joint 3, and the yokes 5 and 6 are attached to the upper and lower ends of the lower shaft 4, respectively, and the corresponding steering shaft 1 and gear shaft 7
Yokes 8 and 9 are respectively attached to the ends of the yokes 8 and 9, and are swingably connected by trunnions 10a and 10b. Furthermore, the lower joint 3 is equipped with a vibration-proofing structure to prevent road vibrations from the tires and vibrations from the engine, suspension, etc. from being transmitted into the vehicle interior through the steering shaft 1. As shown in FIG. 10, the vibration isolating structure has a disc-shaped vibration isolating rubber 11 fixed to the tip of the lower shaft 4 with bolts 12 and nuts 13, and a yoke 5 is connected to the vibration isolating rubber 11.
Therefore, when road vibrations from the tires are transmitted to the lower joint 3, most of the vibrations are absorbed by the anti-vibration rubber 11, and vibrations and abnormal noises are transmitted through the steering shaft 1 into the vehicle interior. is prevented from being transmitted.

By the way, in this type of lower joint 3, as the yoke 5 fixed to the vibration isolating rubber 11, those shown in FIGS. 10 to 12 are conventionally known. This is a metal plate consisting of a diamond shape,
It is bent at both sides in the longitudinal direction to form a substantially U-shaped cross section, with holes 14a for attaching vibration-proof rubber,
It consists of a base part 15 which is opened at the opposite end position of the trunnion 14b, and yoke parts 17a and 17b which are provided with bearing mounting holes 16a and 16b for supporting the trunnion 10a.
(Refer to Publication No. 172930).

As shown in FIG.
In this case, the anti-vibration rubber 11 is attached to the mounting flanges 18a and 18b that protrude in the left and right direction at the tip of the lower shaft 4 through the bolts 1.
2. Fixed by nut 13 and yoke 5
is placed on the anti-vibration rubber 11 between the left and right anti-vibration rubber fixing bolts 12, 12 protruding from the upper surface of the anti-vibration rubber 11, and is located on a line substantially perpendicular to the straight line connecting the bolts 12, 12. Bolt 1 to anti-vibration rubber 11
It was fixed at 9. Further, the yoke 8 on the steering shaft 1 side is connected to the yoke 5 fixed to the tip of the lower shaft 4 through the trunnion 10a supported in the bearing mounting holes 16a, 16b of the yoke parts 17a, 17b. They were connected so that they could swing freely.

[Problem that the invention seeks to solve]

By the way, in the case of the lower joint 3 having the above-mentioned vibration-proof structure, the diameter dimension of the vibration-proof rubber 11 is determined by the size of the yoke 5, but the conventional yoke 5 has a rhombic shape. The base portion 15 and the yoke portion 17 are formed by simply bending a shaped metal plate.
a, 17b, the bolts 12 when fastening the vibration isolating rubber 11 to the lower shaft 4 must be located outside the yoke parts 17a, 17b, and the vibration isolating rubber 11 As the shape of the lower joint 3 becomes larger, there are problems in that the lower joint 3 itself becomes larger and heavier, and the effective space in the vicinity is narrowed.

[Means for solving problems]

The present invention aims to solve the above-mentioned conventional problems by providing a yoke for a universal joint that can reduce the size of the yoke attachment part. In a yoke for a universal joint that is attached through a material, the yoke is a plate material having a base portion and yoke portions protruding from both sides of the base portion, and a folding line in which each of the yoke portions is set as the base portion. By drawing it up as a reference, it is formed by a base part with both sides cut out and a yoke part rising from this base part, and a part of the base part including the center part of the folded line and a part of the yoke part is formed by the base part. The vibration material mounting surface and the yoke part are embossed inward from the outer surface of the trunnion mounting area to form a recess that accommodates a part of the fastener for attaching the vibration damping material to the shaft. .

[Embodiments of the invention]

Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings.

Yoke 21 of this embodiment shown in FIGS. 1 to 4
As in the past, a metal plate material having a predetermined shape is pressed to have a substantially U-shaped cross section, but the metal plate material 22 according to this embodiment has a shape as shown in FIG. , a circular base portion 23;
A yoke portion 24a having a substantially equal width dimension W and projecting from both sides of the base portion 23 with rounded corners;
24b. A yoke portion 24 inside the base portion 23 of this plate material 22
Folding lines 26a and 26b intersecting the long axis 25 of the plate material 22 are set near a and 24b, and for example, a lower die 27a and an upper die 27b as shown in FIG.
It is molded by press working using a yoke molding device 27 consisting of. In this press working, the yoke portions 24a and 24b on both sides are raised with reference to the folding lines 26a and 26b, and a circular base portion 28 with both sides cut out and a radius 29 are formed from this base portion 28 and stand up. Yoke portions 30a and 30b having approximately equal widths are formed. Note that the attached radius 29 includes a convex radius 29a attached to the rising portion of the base portion 28 and a concave radius 29b following this convex radius 29a, as shown in FIGS. 1 and 4 due to molding. This concave radius 29b smoothly connects to the upper portions of the yoke portions 30a and 30b.

In addition, in this embodiment, the yoke forming device 2
Projections 31a, 31b and recesses 32a, 32b are provided at the corners of the lower mold 27a and the corresponding tip sides of the upper mold 27b, respectively.
The surrounding parts of the folding lines 26a and 26b set to 2,
That is, embossing is performed on the cutout side of the base portion 28 including the central portions of the folding lines 26a and 26b and on the lower side of the yoke portions 30a and 30b. Therefore, by this embossing, inward reinforcing ribs 33a, 33b are formed in the yoke 21, spanning the base portion 28 and the yoke portions 30a, 30b.
The reinforcing ribs 33a, 33b reliably prevent spring back of the yoke parts 30a, 30b, and increase the trunnion support strength of the yoke parts 30a, 30b. Furthermore, by the embossing, recesses 34a and 34b having sizes corresponding to the reinforcing ribs 33a and 33b are formed on the back sides of the reinforcing ribs 33a and 33b. As shown in FIGS. 1 and 7, the recesses 34a and 34b are formed by a vibration-proof material mounting surface 28a, which is the lower surface of the base portion 28, and outer surfaces 52a and 52b of the trunnion mounting portions of the yoke portions 30a and 30b. Since the recesses 34a and 34b are formed to protrude more inward than the recesses 34a and 34b,
This will allow you to store the yoke mounting bolts, which will be described later.

Incidentally, bolt insertion holes 36a for attaching a vibration isolating rubber 35, which will be described later, are provided on the flat surfaces at both ends of the base portion 28.
36b is provided, and the left and right yoke portions 3
Bearing mounting holes 37a and 37b for supporting trunnions are provided in the upper portions of 0a and 30b, respectively.

Next, the case where the yoke 21 having the above shape is used as a universal joint between the steering shaft 1 and the lower joint 3 as in the conventional example will be explained based on FIGS. 5 to 7. Disc-shaped vibration-proofing rubber 35 as a vibration-proofing material
The anti-vibration rubber 35 in this embodiment is in the shape of a disk having a diameter that is approximately the same as the maximum diameter at both ends of the base portion 23 of the yoke 21, and the inside is reinforced with fibers. Four bolt insertion holes 38a, 38b, 38c, and 38d are formed on the same radius on an orthogonal line passing through the center of the circle. Among these, a pair of bolt insertion holes 38a and 38c located at opposing positions are provided with bolts 40a and 40 as fasteners for fixing the lower shaft 39.
Bushes 41a and 41c that protrude from the bottom side are installed inside the bushings 41a and 41c. Also, a pair of bolt insertion holes 3 perpendicular to this
Numerals 8b and 38d are for inserting bolts 40b and 40d as fasteners for fixing the yoke 21, and bushes 41b and 41d projecting upward are mounted inside the bolts 40b and 40d. Further, each of the above-mentioned bushes 41a, 41c, 41b, 41d has plastic collars 42a, 42c,
42b, 42d are fitted on the outside, and the plastic collars 42a, 42c, 42b, 42d are fitted on the bottom and top sides of the vibration isolating rubber 35, respectively.
The stopper plate 43a,
43b are interposed respectively. The stopper plates 43a, 43b are made of metal disk members that are shared with each other, and have bolt holes 44a, 44b on both sides corresponding to the bolt insertion holes 38a (38b), 38c (38d) of the vibration isolating rubber 35. In addition to this, cutout recesses 45a and 45b into which plastic collars 42a (42b) and 42c (42d) are fitted are formed at positions 90 degrees apart.
These stopper plates 43a, 43b prevent the vibration isolating rubber 35 from twisting when the joint portion rotates, and function as stoppers by touching the notched edges of the notched recesses 45a, 45b to the plastic collar. . The notch edge is formed so as to be curved against the surface of the vibration isolating rubber 35, thereby preventing it from digging into the vibration isolating rubber 35. Further, a mounting flange 46 projecting to the left and right is integrally provided at the tip of the lower shaft 39, and a serration 47 for attaching a yoke on the gear shaft side is provided at the rear end.

Therefore, when assembling the yoke 21 to the lower joint 3 provided with the above-mentioned anti-vibration structure, the anti-vibration rubber fixing bolts 40a, 40c are inserted into the bolt holes 48a, 48b formed at the left and right ends of the mounting flange 46 of the lower shaft 39. Insert this bolt 40a,
Bolt insertion holes 38a, 38c of the anti-vibration rubber 35 are inserted through the plastic collars 42a, 42c to 40c.
Then, bolt holes 44a and 44c of a stopper plate 43b arranged on the upper surface of the vibration isolating rubber 35 are passed through, and nuts 49a and 49a are inserted into the tips of the bolts 40a and 40c that protrude above the stopper plate 43b.
By screwing 49c together, the lower shaft 3
Attach the anti-vibration rubber 35 to the mounting flange 46 of 9.

Next, when attaching the yoke 21 to the upper surface of the anti-vibration rubber 35, use the bolts 40 for fastening the anti-vibration rubber.
The recess 3 of the yoke 21 is located at the tip protruding portion of a and 40c.
Place the yoke 21 so that the yoke 4a and 34b are positioned, and insert the bolt insertion hole 3 from the upper surface of the base portion 28.
Bolts 40b, 4 for fastening the yoke to 6a, 36b
Insert 0d. And this bolt 40b, 4
0d through the bolt insertion holes 38b, 38d of the vibration isolating rubber 35 and the bolt holes 44a, 44b of the stopper plate 43a arranged on the lower surface of the vibration isolating rubber 35 through the plastic collars 42b, 42d, and from the stopper plate 43a. The yoke 21 is attached to the vibration isolating rubber 35 by screwing nuts 49b and 49d onto the protruding tips. In addition, as shown in FIG. 8, a pin 50 is used instead of the bolt fastening means.
The yoke 21 and the vibration isolating rubber 35 can also be attached to the lower shaft 39 by the fixing means provided by a, 50b, 50c, and 50d.

In this way, in the case of the lower joint 3 to which the yoke 21 is attached, since the base portion 23 of the yoke 21 has the same basic circular shape as the vibration isolating rubber 35, the base portion is inside the vibration isolating rubber 35. 28 can be accommodated in its entirety, and the yoke 21 can be rotated within the rotation radius of the vibration isolating rubber 35.

Further, in this embodiment, reinforcing ribs 33a and 33 that span the base portion 28 and the yoke portions 30a and 30b are
Since the rigidity of the yoke portions 30a, 30b is increased by forming the yoke portions 30a, 30b, the yoke portions 30a, 30b are different from the conventional yoke formed by bending a diamond-shaped metal plate.
30b can be raised from the base part 28 with approximately the same width, and as shown in FIG. The degree of freedom increases when laying out a steering device for an automobile.

In addition, in this embodiment, the tip protrusions of the bolts 40a and 40c for fastening the vibration isolating rubber 35 are connected to the yoke 21.
In order to accommodate the bolts 40a, 40c in the recesses 34a, 34b, the bolts 40a, 40c are located on the same circumference as the yoke fastening bolts 40b, 40d.
That is, it can be provided within the circular base portion 23 that forms the base portion 28 of the yoke 21, and the shape of the vibration isolating rubber 35 itself can be reduced.

Furthermore, the reinforcing ribs 33a, 33b and recesses 34a, 3 formed in the yoke 21 in the above embodiment
4b is embossed at the same time as the yoke is molded, so the molding operation is extremely simple.

〔Effect of the invention〕

As explained above, according to the yoke for a universal joint according to the present invention, the lower side of the yoke part is embossed inward from the outer surface of the trunnion attachment part,
Since reinforcing ribs were formed on the inside of the yoke and recesses for storing fasteners were formed on the outside, the yoke itself could be formed into a compact shape. Also, when configuring a universal joint, a part of the fastener for attaching the vibration isolator can be stored in the recess of the yoke.
The shape of the vibration isolator itself, especially the diameter, can be made smaller. As a result, the weight of the entire universal joint can be reduced, and the maximum diameter when the universal joint rotates can be reduced, and the space around the universal joint can be effectively utilized.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a yoke for a universal joint according to the present invention, Fig. 2 is a plan view of the yoke, Fig. 3 is a sectional view showing an embodiment of a yoke forming device, and Fig. 4 is a side view of the yoke. Fig. 5 is an exploded perspective view of the members constituting the lower joint, Fig. 6 is an assembled view of the lower joint, Fig. 7 is a partial cross-sectional view taken along the line - - in Fig. 6, and Fig. 8 shows the parts of the lower joint with different fastening means. 9 is a perspective view schematically showing the steering device, FIG. 10 is an assembly view showing an example of a conventional lower joint, FIG. 11 is a plan view showing an example of a conventional yoke, and FIG. The figure is in Figure 11-
FIG. 3 is a partial cross-sectional view of the line. 21...Yoke, 22...Metal plate material, 23...
...base part, 24a, 24b...yoke part,
26a, 26b... bending line, 28... base part,
30a, 30b...Yoke part, 33a, 33b...
...Reinforcement ribs, 34a, 34b... recesses.

Claims (1)

[Claims] 1. A yoke for a universal joint that is attached to the tip of a shaft via a vibration isolating material, the yoke being made of a plate material having a base portion and yoke portions protruding from both sides of the base portion. ,
By raising each of the yoke parts based on the folding line set in the base part, a base part with both sides removed and a yoke part rising from this base part are formed, and the yoke part includes the center part of the folding line. Parts of the base and yoke are embossed inward from the vibration isolator attachment surface of the base and the outer surface of the trunnion attachment portion of the yoke, and a fastener for attaching the vibration isolator to the shaft is formed. A yoke for a universal joint characterized by forming a recess for storing a portion of the yoke. 2. The plate material includes a circular base portion and yoke portions having approximately equal width and projecting from both sides of the base portion with rounded corners.
Yoke for universal joints as described in section.