JPS6127328Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a sealing structure for a center arm bracket that rotatably supports the shaft of a center arm used in a steering link casing of an automobile.

The center arm bracket described above is formed into a cylindrical shape with a conical inner peripheral surface that rotatably supports the center arm shaft. Consideration must be given to the infiltration of
The area that requires a seal to prevent the infiltration of muddy water, etc. is between the above-mentioned bracket and the shaft nut screwed into the upper opening of this bracket, but this shaft nut not only functions as a cap for the bracket, but also functions as a cap for the bracket. It also has the function of applying preload to the center arm shaft. For this reason, even if an O-ring sealing material is interposed between the thrust surface of the bracket and the shaft nut, the sealing material may be damaged due to changes in the screwing amount of the shaft nut for the above-mentioned preload adjustment, machining errors between each member, etc. The axial dimensions of the intervening locations change, making it extremely difficult to obtain a consistent sealing function.

The object of this invention is to provide a sealing structure for a center arm bracket that can absorb changes in the sealing gap due to the causes mentioned above and always exhibit an appropriate sealing function.

Next, the configuration of this invention will be explained in detail according to an embodiment shown in the drawings.

First, in FIG. 1, a center arm bracket 1 has a conical inner peripheral surface 2, on which a center arm shaft 6 is rotatably supported with a bush 5 interposed therebetween. The lower end of the shaft 6 projects outward from the lower surface of the bracket 1, and a center arm 15 is integrally attached to this projecting portion. On the other hand, a shaft nut 10 is screwed into the upper opening 3 of the bracket 1, and the lower surface of this nut 10 and the shaft 6
A compression spring 9 and a lock plate 7 are interposed between the upper end and the upper end. In addition, the lock plate 7 and the bush 5 mentioned above
The rotation of the bracket 1 is prevented by locking claws 7' and 5' formed on each part into the recess 4 of the bracket 1.

By adjusting the screwing amount of the nut 10, a preload is applied to the center arm shaft 6, and by this preload, play in the axial direction of the shaft 6 with respect to the bracket 1 is reduced. After that, the bolt 11 is tightened from the upper surface side of the nut 10 to the boss portion 8 of the lock plate 7 to integrate the shaft nut 10 and the lock plate 7,
It also prevents the shaft nut 10 from loosening. The hexagonal nut-shaped portion 10' fixed at the center of the upper surface of the shaft nut 10 is
It is used when screwing this shaft nut 10 into the bracket 1.

Now, on the outer periphery of the shaft nut 10, there is a flange portion 1 facing the upper end surface 1' of the bracket 1.
2 are integrally formed. This flange portion 12
As is clear from FIG. 2, an annular tapered groove 13 is formed in the lower surface of the bracket 1, that is, the surface facing the upper end surface 1' of the bracket 1, and the groove width gradually decreases upward. And, between the flange portion 12 and the upper end surface 1' of the bracket 1,
An annular sealing material 14 using a ring or the like is provided to prevent muddy water or the like from entering the inside of the bracket 1.

In the above configuration, the screwing amount of the shaft nut 10 into the bracket 1 is not constant due to the preload adjustment for the center arm shaft 6 mentioned above, and there is a machining error between each member. The dimension D between the end surface 1' and the lower surface of the flange portion 12 of the shaft nut 10 changes. In this embodiment, when the above-mentioned dimension D is a design value, the sealing material 14 is set so as to be slightly elastically deformed and fit into the tapered groove 13 (see Fig. 2). .
Therefore, even if the above-mentioned dimension D is larger than the design value, the sealing performance is maintained by the elastic force of the sealing material 14 (see Fig. 3), and conversely, if the dimension D is small, the sealing material 14 will further expand into the tapered groove. The sealing property is maintained by fitting into the hole 13 (see FIG. 4).

Note that the sealing material 14 may be of the S-ring type shown in FIG. 5 instead of the above-mentioned O-ring. Also, the taper groove 13 is connected to the bracket 1.
It is also conceivable to form it on the upper end surface 1' of the.

As described above, the present invention forms a tapered groove on either the upper end surface of the center arm bracket or the flange portion of the shaft nut to receive the sealing material interposed therebetween, and The sealing material fits into the tapered groove according to the change, so regardless of changes in the screwing amount of the shaft nut or errors in the machining dimensions between each component, it absorbs the dimensional changes caused by these and always maintains the proper level. Demonstrates sealing function,
This also prevents muddy water from entering the center arm bracket.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention; FIG. 1 is a sectional view of the center arm bracket, and FIG. 2 is a cross-sectional view of the center arm bracket.
Figures 3 and 4 are cross-sectional views showing enlarged main parts of the figure, and Figures 3 and 4 show the state in which the dimensions of the sealing area have changed.
FIG. 5 is a cross-sectional view of a different embodiment, also shown in correspondence with FIG. 2. 1... Center arm bracket, 1'... Upper end surface,
2... Conical inner peripheral surface, 3... Top opening, 10... Shaft nut, 12... Flange portion, 13... Tapered groove, 14... Sealing material.

Claims (1)

[Scope of utility model registration request] An arm bracket rotatably supports a center arm shaft of a steering wheel by a conical inner circumferential surface, and a shaft nut screwed into an upper opening of the bracket to apply preload to the center arm shaft, An annular sealing material is interposed between the upper end surface of the bracket and a flange portion formed on the shaft nut side opposite thereto, and on either the upper end surface or the flange portion of the bracket where this sealing material is arranged, A seal structure for a center arm bracket, characterized in that a tapered groove is formed along the axis of the center arm shaft so that the groove width becomes smaller.