JPH0439092Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an elastic shaft joint for a steering shaft that connects an upper shaft and a lower shaft of the steering shaft.

BACKGROUND ART Generally, an elastic shaft joint is provided in the steering shaft of an automobile, as shown in Fig. 1 of Utility Model Application No. 57-179572. It is designed to absorb road vibrations and shimmy. As such an elastic shaft coupling, there is one shown in FIG. 4 in the past. That is, this elastic shaft joint 1
is a disc-shaped elastic body 2 made of rubber, a holding plate 3 disposed opposite to this elastic body 2, and this holding plate 3.
and a pin 4 that connects the elastic body 2 at the peripheral edge thereof, the elastic body 2 is attached to an upper shaft 5 to which a steering wheel (not shown) is attached, and the retaining plate 3 is Lower shaft 6 connected to steering linkage (not shown)
It is now being installed on A first stopper plate 7 and a second stopper plate 8 are provided at both ends of the elastic body 2 in the shaft axis direction (in the left-right direction in the figure) to prevent bending deformation of the elastic body 2.
are now in contact with each other. By the way, the outer diameter end portions of the first stopper plate 7 and the second stopper plate 8 are bent in the direction away from the elastic body 2 to form a relief portion 9, and the outer diameter end portions and the elastic body 2 are bent. A gap δ is provided between the two. Therefore, the relief portion 9 allows the elastic body 2 to be flexibly deformed, and bending between the upper shaft 5 and the lower shaft 6 is permitted.

Problems to be solved by the invention However, the conventional elastic shaft coupling 1 has the following problems:
The relief portion 9 formed in the first and second stopper plates 7, 8 is sharply bent from the contact portion 8a to the elastic body 2 with a step portion 9a, as shown in the figure. There is a gap δ from 9a toward the outer diameter end.
The elastic body 2 extends substantially parallel to the end surface of the elastic body 2. Therefore, due to the bending moment acting on the elastic shaft joint 1, the outer diameter portion of the elastic body 2 is easily bent and deformed by the distance δ from the stepped portion 9a, but the bending rigidity due to the elastic body at this time is is determined by the diameter γ of the stepped portion 9a. However, the diameter γ of the stepped portion 9a cannot be made very large because the area of the abutting portion 8a becomes large. That is, when the area of the corresponding contact portion 8a becomes larger,
The soundproofing effect of measures against abnormal noise peculiar to power steering will be reduced. For this reason, the bending rigidity of the elastic shaft joint 1 becomes low, making it difficult to use the elastic shaft joint 1 in a two-joint type steering column such as an F/F (front engine front drive) vehicle. It ends up. Therefore, it is conceivable to increase the thickness of the elastic body 2 in order to improve its flexural rigidity, but in this case, the rigidity of the elastic body 2 in the rotational direction will also inevitably increase, causing problems such as shimmy. There was a problem in that vibrations in the rotational direction were significantly aggravated.

Therefore, the present invention has been developed to improve the elasticity of the steering shaft by changing the shape of the stepped part of the stopper plate so that the contact area between the stopper plate and the elastic body is normally reduced, and the bending rigidity is increased when the elastic body is deformed. The purpose is to provide shaft couplings.

Means for Solving the Problems In order to achieve the above object, the present invention includes an upper shaft to which a steering wheel is mounted;
An elastic body is attached to either one of the lower shafts connected to the steering linkage, and the first stopper plate and the second stopper plate are abutted on both ends of the shaft in the axial direction, and the elastic body is attached to the other of the upper and lower shafts. a retaining plate;
a pin connecting the holding plate and the elastic body; In an elastic shaft joint for a steering shaft, the entire area of the relief portion is provided with a center of curvature at a position opposite to the elastic body, and a gap with the end surface of the elastic body extends in the outer radial direction. It is constructed by forming it into an arc shape that gradually becomes larger as it goes.

Effect With the above structure, in the elastic shaft joint for a steering shaft of the present invention, the relief part of the stopper plate is formed in an arc shape, and the gap between the stopper plate and the elastic body is formed in the relief part. It gradually becomes larger as it goes in the outer radial direction from the formation starting end. Therefore, under normal conditions when the elastic body does not undergo flexural deformation, the contact area between the stopper plate and the elastic body is determined by the area inside the relief portion forming starting end of the stopper plate. By setting the forming starting end diameter small,
The contact area can be reduced. on the other hand,
When the elastic body undergoes bending deformation, the elastic body is deformed along the arcuate relief portion, and the contact area between the stopper plate and the elastic body changes in the outer radial direction according to the amount of deformation of the elastic body. Increased gradually. Therefore, as the contact area increases, the bending rigidity of the elastic body gradually increases.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings. Incidentally, in explaining this embodiment, the same parts as those in the conventional structure will be described with the same reference numerals.

That is, FIGS. 1 and 2 show an elastic shaft joint 1a of a steering shaft according to an embodiment of the present invention, 5 is an upper shaft, 6 is a lower shaft, and these upper and lower shafts 5 and 6 are connected to the elastic shaft. They are connected to each other via a joint 1a.
The elastic body 2 of the elastic shaft joint 1a is formed into a disc shape from an elastic member such as rubber, and the circumference of the elastic body 2 has mounting holes 11 for the pin 4 and mounting holes 11a for the pin 4a at approximately equal intervals. is formed. On the other hand, a retaining plate 3 attached to the lower shaft 6 is arranged to face the elastic body 2, and the peripheral edge of the retaining plate 3 has an insertion hole for a pin 4 corresponding to the mounting hole 11 of the elastic body 2. 12 are formed. By the way, the elastic body 2
At both ends, a first stopper plate 7 is arranged on the upper shaft 5 side, and a second stopper plate 8 is arranged on the lower shaft 6 side. The first of these,
As shown in FIGS. 3A and 3B, the second stopper plates 7 and 8 have cutout openings 7a in which a pair of opposing parts are narrowed, and
8a, and a pair of mounting holes 7b, 8b are formed in a direction perpendicular to the direction in which the cutout openings 7a, 8a face each other. The first and second stopper plates 7 and 8 are arranged on both sides of the elastic body 2 with a phase of 90°, and when installing the first stopper plate 7, the pin 4
is passed through the mounting hole 7b of the first stopper plate 7, and the pin 4 is inserted into the mounting hole 11 of the elastic body 2, the notch opening 8a of the second stopper plate 8, and the insertion hole 12 of the retaining plate 3. The tips of the pins 4 are fixed to the holding plate 3 by caulking. On the other hand, when attaching the second stopper plate 8, the pin 4a is passed through the attachment hole 8b of the second stopper plate 8 to the attachment hole 11a of the elastic body 2 and the notch opening of the first stopper plate 7. 7
The pins 4a are inserted through the flange portions 5a of the upper shaft 5, and the tips of the pins 4a are caulked and fixed to the flange portions 5a. Furthermore, on the outer periphery of the pins 4, 4a, there are a first stopper plate 7, a retaining plate 3, a second stopper plate 8, and a flange portion 5a.
Bushes 13, 13a are fitted between the retaining plate 3 and the elastic body 2, and the flange portion 5a is fitted on the outer periphery of the bushes 13, 13a.
and the elastic body 2.
4 and 14a are fitted.

In this embodiment, as shown in FIG. The relief part 20 is formed by having a center of curvature at a side position and curving in an arc shape with a large curvature in a direction in which the gap with the end surface of the elastic body 2 gradually increases as it goes in the outer radial direction. There is. Further, the central portion protrudes in a direction away from the elastic body 2 to short-circuit between the respective notch openings 7a and 8a.

In addition, as a means of fixing the stopper plate and elastic body to the upper part and lower shaft, a pin is inserted through the pin and crimped to the retaining plate. Good too. Also, instead of the pin, a bolt or nut may be used as the fixing means.

With the above configuration, the elastic shaft joint 1a of this embodiment
In this case, as in the conventional case, vibrations from the road surface, shimmy, etc. and abnormal power steering noise transmitted from the lower shaft 6 to the upper shaft 5 are absorbed by the elastic body 2 of the elastic shaft joint 1a, and the steering wheel vibration is reduced. Reduced. By the way, the elastic shaft joint 1a is attached to the upper and lower shafts 5 and 6.
The bending in between is allowed by the bending deformation of the elastic body 2, and this bending deformation of the elastic body 2 is performed by the relief portion 20 of the second stopper plate 8.
Since this relief portion 20 is formed in an arc shape with a large curvature, the formation starting end 2 of the relief portion 20
From 0a to the outer end of the second stopper plate 8, the gap between the second stopper plate 8 and the end surface of the elastic body 2 is set to gradually increase. Therefore, when the elastic body 2 bends and deforms, the elastic body 2 moves toward the relief portion 20 according to the amount of the bending deformation.
The area in contact with is gradually increased. In other words,
In this way, the elastic body 2 and the second stopper plate 8
By gradually increasing the contact area between
The bending rigidity of the elastic body 2, ie, the bending rigidity of the elastic shaft joint 1a, is gradually increased. On the other hand, under normal conditions when no bending moment acts on the elastic shaft joint 1a, the elastic body 2 does not come into contact with the relief portion 20,
The contact area between the elastic body 2 and the second stopper plate 8 is equal to the relief portion 2 of the second stopper plate 8.
By setting the forming starting end 20a to a small diameter, the contact area in the normal state can be reduced, and power steering noise, shimmy, etc. can be reduced. The prevention effect can be improved. In addition, in this embodiment, as described above, the improvement in the bending rigidity of the elastic body 2 is achieved through the relief portion 2.
0, the thickness of the elastic body 2 can be made thinner, and the rigidity of the elastic body 2 in the rotational direction can be made smaller. Therefore, this also makes it possible to further reduce vibrations in the rotational direction such as shimmy.

Effects of the Invention As explained above, in the elastic shaft joint for a steering shaft of the present invention, the relief part of the stopper plate that comes into contact with the end face of the elastic body is defined by the gap between the stopper plate and the end face of the elastic body. is formed in an arc shape that gradually increases as it goes in the outer diameter direction, so when the elastic body is deflected, the contact area between the elastic body and the relief portion changes according to the amount of deflection deformation. is gradually increased, and the flexural stiffness is gradually increased. On the other hand, under normal conditions when the elastic body is not flexibly deformed, the contact area between the stopper plate and the elastic body is determined by the diameter of the starting end of the relief portion, and the diameter of the starting end of the relief portion is reduced to a certain extent. By installing the same, it is possible to improve the vibration-proofing effect against power steering noise, shimmy, etc. Therefore, in the present invention, when the elastic body is flexibly deformed, the contact area between the elastic body and the relief portion is gradually increased, so that the flexural rigidity gradually increases, and the elastic body is not flexibly deformed. Under normal conditions, the diameter of the starting end of the relief portion can be reduced to further improve the vibration damping effect, which is an excellent effect.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional side view of essential parts of an elastic shaft joint for a steering shaft showing an embodiment of the invention, Fig. 2 is an exploded perspective view of the invention, and Fig. 3 shows a stopper plate used in the invention. , Figure A is a plan view, Figure B is a sectional view taken from the line - in Figure A, and the fourth
The figure is a side view of a conventional elastic shaft joint for a steering shaft. 1a...Elastic shaft joint, 2...Elastic body, 3...Holding plate, 4...Pin, 5...Upper shaft, 6
...lower shaft, 7,8...stopper plate, 20...relief part.

Claims (1)

[Scope of utility model registration request] It is attached to either the upper shaft to which the steering wheel is attached or the lower shaft connected to the steering linkage, and a first stopper plate and a second stopper plate are attached to both ends of the shaft in the axial direction.
The first stopper plate and the second stopper plate include an elastic body to which the stopper plate is abutted, a retaining plate attached to the other of the upper and lower shafts, and a pin connecting the retaining plate and the elastic body. In an elastic shaft joint for a steering shaft in which an outer diameter end of a stopper plate is bent to provide a relief portion that forms a gap between the stopper plate and the elastic body, the entire area of the relief portion is An elastic shaft joint for a steering shaft, characterized in that the center of curvature is at a position opposite to the elastic body, and the gap with the end face of the elastic body is formed in an arc shape that gradually increases in the outer radial direction. .